Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 478df7e..fd188b9 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -44,8 +44,10 @@
#include <linux/errno.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
+#include <net/compat.h>
#include <linux/refcount.h>
#include <linux/uio.h>
+#include <linux/bits.h>
#include <linux/sched/signal.h>
#include <linux/fs.h>
@@ -53,10 +55,8 @@
#include <linux/fdtable.h>
#include <linux/mm.h>
#include <linux/mman.h>
-#include <linux/mmu_context.h>
#include <linux/percpu.h>
#include <linux/slab.h>
-#include <linux/workqueue.h>
#include <linux/kthread.h>
#include <linux/blkdev.h>
#include <linux/bvec.h>
@@ -71,14 +71,38 @@
#include <linux/sizes.h>
#include <linux/hugetlb.h>
#include <linux/highmem.h>
+#include <linux/namei.h>
+#include <linux/fsnotify.h>
+#include <linux/fadvise.h>
+#include <linux/eventpoll.h>
#include <linux/fs_struct.h>
+#include <linux/splice.h>
+#include <linux/task_work.h>
+#include <linux/pagemap.h>
+#include <linux/io_uring.h>
+#include <linux/blk-cgroup.h>
+#include <linux/audit.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/io_uring.h>
#include <uapi/linux/io_uring.h>
#include "internal.h"
+#include "io-wq.h"
#define IORING_MAX_ENTRIES 32768
-#define IORING_MAX_FIXED_FILES 1024
+#define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
+
+/*
+ * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
+ */
+#define IORING_FILE_TABLE_SHIFT 9
+#define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
+#define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
+#define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
+#define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
+ IORING_REGISTER_LAST + IORING_OP_LAST)
struct io_uring {
u32 head ____cacheline_aligned_in_smp;
@@ -123,7 +147,7 @@
*/
u32 sq_dropped;
/*
- * Runtime flags
+ * Runtime SQ flags
*
* Written by the kernel, shouldn't be modified by the
* application.
@@ -133,9 +157,16 @@
*/
u32 sq_flags;
/*
+ * Runtime CQ flags
+ *
+ * Written by the application, shouldn't be modified by the
+ * kernel.
+ */
+ u32 cq_flags;
+ /*
* Number of completion events lost because the queue was full;
* this should be avoided by the application by making sure
- * there are not more requests pending thatn there is space in
+ * there are not more requests pending than there is space in
* the completion queue.
*
* Written by the kernel, shouldn't be modified by the
@@ -161,16 +192,59 @@
size_t len;
struct bio_vec *bvec;
unsigned int nr_bvecs;
+ unsigned long acct_pages;
};
-struct async_list {
- spinlock_t lock;
- atomic_t cnt;
- struct list_head list;
+struct fixed_file_table {
+ struct file **files;
+};
- struct file *file;
- off_t io_start;
- size_t io_len;
+struct fixed_file_ref_node {
+ struct percpu_ref refs;
+ struct list_head node;
+ struct list_head file_list;
+ struct fixed_file_data *file_data;
+ struct llist_node llist;
+ bool done;
+};
+
+struct fixed_file_data {
+ struct fixed_file_table *table;
+ struct io_ring_ctx *ctx;
+
+ struct fixed_file_ref_node *node;
+ struct percpu_ref refs;
+ struct completion done;
+ struct list_head ref_list;
+ spinlock_t lock;
+};
+
+struct io_buffer {
+ struct list_head list;
+ __u64 addr;
+ __u32 len;
+ __u16 bid;
+};
+
+struct io_restriction {
+ DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
+ DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
+ u8 sqe_flags_allowed;
+ u8 sqe_flags_required;
+ bool registered;
+};
+
+struct io_sq_data {
+ refcount_t refs;
+ struct mutex lock;
+
+ /* ctx's that are using this sqd */
+ struct list_head ctx_list;
+ struct list_head ctx_new_list;
+ struct mutex ctx_lock;
+
+ struct task_struct *thread;
+ struct wait_queue_head wait;
};
struct io_ring_ctx {
@@ -180,8 +254,13 @@
struct {
unsigned int flags;
- bool compat;
- bool account_mem;
+ unsigned int compat: 1;
+ unsigned int limit_mem: 1;
+ unsigned int cq_overflow_flushed: 1;
+ unsigned int drain_next: 1;
+ unsigned int eventfd_async: 1;
+ unsigned int restricted: 1;
+ unsigned int sqo_dead: 1;
/*
* Ring buffer of indices into array of io_uring_sqe, which is
@@ -200,38 +279,46 @@
unsigned sq_mask;
unsigned sq_thread_idle;
unsigned cached_sq_dropped;
- struct io_uring_sqe *sq_sqes;
+ unsigned cached_cq_overflow;
+ unsigned long sq_check_overflow;
struct list_head defer_list;
struct list_head timeout_list;
- } ____cacheline_aligned_in_smp;
+ struct list_head cq_overflow_list;
- /* IO offload */
- struct workqueue_struct *sqo_wq[2];
- struct task_struct *sqo_thread; /* if using sq thread polling */
- struct mm_struct *sqo_mm;
- wait_queue_head_t sqo_wait;
- struct completion sqo_thread_started;
-
- struct {
- unsigned cached_cq_tail;
- atomic_t cached_cq_overflow;
- unsigned cq_entries;
- unsigned cq_mask;
- struct wait_queue_head cq_wait;
- struct fasync_struct *cq_fasync;
- struct eventfd_ctx *cq_ev_fd;
- atomic_t cq_timeouts;
+ struct io_uring_sqe *sq_sqes;
} ____cacheline_aligned_in_smp;
struct io_rings *rings;
+ /* IO offload */
+ struct io_wq *io_wq;
+
+ /*
+ * For SQPOLL usage - we hold a reference to the parent task, so we
+ * have access to the ->files
+ */
+ struct task_struct *sqo_task;
+
+ /* Only used for accounting purposes */
+ struct mm_struct *mm_account;
+
+#ifdef CONFIG_BLK_CGROUP
+ struct cgroup_subsys_state *sqo_blkcg_css;
+#endif
+
+ struct io_sq_data *sq_data; /* if using sq thread polling */
+
+ struct wait_queue_head sqo_sq_wait;
+ struct wait_queue_entry sqo_wait_entry;
+ struct list_head sqd_list;
+
/*
* If used, fixed file set. Writers must ensure that ->refs is dead,
* readers must ensure that ->refs is alive as long as the file* is
* used. Only updated through io_uring_register(2).
*/
- struct file **user_files;
+ struct fixed_file_data *file_data;
unsigned nr_user_files;
/* if used, fixed mapped user buffers */
@@ -242,7 +329,37 @@
const struct cred *creds;
- struct completion ctx_done;
+#ifdef CONFIG_AUDIT
+ kuid_t loginuid;
+ unsigned int sessionid;
+#endif
+
+ struct completion ref_comp;
+ struct completion sq_thread_comp;
+
+ /* if all else fails... */
+ struct io_kiocb *fallback_req;
+
+#if defined(CONFIG_UNIX)
+ struct socket *ring_sock;
+#endif
+
+ struct xarray io_buffers;
+
+ struct xarray personalities;
+ u32 pers_next;
+
+ struct {
+ unsigned cached_cq_tail;
+ unsigned cq_entries;
+ unsigned cq_mask;
+ atomic_t cq_timeouts;
+ unsigned cq_last_tm_flush;
+ unsigned long cq_check_overflow;
+ struct wait_queue_head cq_wait;
+ struct fasync_struct *cq_fasync;
+ struct eventfd_ctx *cq_ev_fd;
+ } ____cacheline_aligned_in_smp;
struct {
struct mutex uring_lock;
@@ -251,35 +368,27 @@
struct {
spinlock_t completion_lock;
- bool poll_multi_file;
+
/*
- * ->poll_list is protected by the ctx->uring_lock for
+ * ->iopoll_list is protected by the ctx->uring_lock for
* io_uring instances that don't use IORING_SETUP_SQPOLL.
* For SQPOLL, only the single threaded io_sq_thread() will
* manipulate the list, hence no extra locking is needed there.
*/
- struct list_head poll_list;
- struct list_head cancel_list;
+ struct list_head iopoll_list;
+ struct hlist_head *cancel_hash;
+ unsigned cancel_hash_bits;
+ bool poll_multi_file;
+
+ spinlock_t inflight_lock;
+ struct list_head inflight_list;
} ____cacheline_aligned_in_smp;
- struct async_list pending_async[2];
+ struct delayed_work file_put_work;
+ struct llist_head file_put_llist;
-#if defined(CONFIG_UNIX)
- struct socket *ring_sock;
-#endif
-
- struct list_head task_list;
- spinlock_t task_lock;
-};
-
-struct sqe_submit {
- const struct io_uring_sqe *sqe;
- unsigned short index;
- u32 sequence;
- bool has_user;
- bool needs_lock;
- bool needs_fixed_file;
- u8 opcode;
+ struct work_struct exit_work;
+ struct io_restriction restrictions;
};
/*
@@ -288,16 +397,249 @@
*/
struct io_poll_iocb {
struct file *file;
- struct wait_queue_head *head;
+ union {
+ struct wait_queue_head *head;
+ u64 addr;
+ };
__poll_t events;
bool done;
bool canceled;
struct wait_queue_entry wait;
};
+struct io_close {
+ struct file *file;
+ struct file *put_file;
+ int fd;
+};
+
+struct io_timeout_data {
+ struct io_kiocb *req;
+ struct hrtimer timer;
+ struct timespec64 ts;
+ enum hrtimer_mode mode;
+};
+
+struct io_accept {
+ struct file *file;
+ struct sockaddr __user *addr;
+ int __user *addr_len;
+ int flags;
+ unsigned long nofile;
+};
+
+struct io_sync {
+ struct file *file;
+ loff_t len;
+ loff_t off;
+ int flags;
+ int mode;
+};
+
+struct io_cancel {
+ struct file *file;
+ u64 addr;
+};
+
struct io_timeout {
struct file *file;
- struct hrtimer timer;
+ u32 off;
+ u32 target_seq;
+ struct list_head list;
+};
+
+struct io_timeout_rem {
+ struct file *file;
+ u64 addr;
+};
+
+struct io_rw {
+ /* NOTE: kiocb has the file as the first member, so don't do it here */
+ struct kiocb kiocb;
+ u64 addr;
+ u64 len;
+};
+
+struct io_connect {
+ struct file *file;
+ struct sockaddr __user *addr;
+ int addr_len;
+};
+
+struct io_sr_msg {
+ struct file *file;
+ union {
+ struct user_msghdr __user *umsg;
+ void __user *buf;
+ };
+ int msg_flags;
+ int bgid;
+ size_t len;
+ struct io_buffer *kbuf;
+};
+
+struct io_open {
+ struct file *file;
+ int dfd;
+ bool ignore_nonblock;
+ struct filename *filename;
+ struct open_how how;
+ unsigned long nofile;
+};
+
+struct io_files_update {
+ struct file *file;
+ u64 arg;
+ u32 nr_args;
+ u32 offset;
+};
+
+struct io_fadvise {
+ struct file *file;
+ u64 offset;
+ u32 len;
+ u32 advice;
+};
+
+struct io_madvise {
+ struct file *file;
+ u64 addr;
+ u32 len;
+ u32 advice;
+};
+
+struct io_epoll {
+ struct file *file;
+ int epfd;
+ int op;
+ int fd;
+ struct epoll_event event;
+};
+
+struct io_splice {
+ struct file *file_out;
+ struct file *file_in;
+ loff_t off_out;
+ loff_t off_in;
+ u64 len;
+ unsigned int flags;
+};
+
+struct io_provide_buf {
+ struct file *file;
+ __u64 addr;
+ __u32 len;
+ __u32 bgid;
+ __u16 nbufs;
+ __u16 bid;
+};
+
+struct io_statx {
+ struct file *file;
+ int dfd;
+ unsigned int mask;
+ unsigned int flags;
+ const char __user *filename;
+ struct statx __user *buffer;
+};
+
+struct io_completion {
+ struct file *file;
+ struct list_head list;
+ u32 cflags;
+};
+
+struct io_async_connect {
+ struct sockaddr_storage address;
+};
+
+struct io_async_msghdr {
+ struct iovec fast_iov[UIO_FASTIOV];
+ struct iovec *iov;
+ struct sockaddr __user *uaddr;
+ struct msghdr msg;
+ struct sockaddr_storage addr;
+};
+
+struct io_async_rw {
+ struct iovec fast_iov[UIO_FASTIOV];
+ const struct iovec *free_iovec;
+ struct iov_iter iter;
+ size_t bytes_done;
+ struct wait_page_queue wpq;
+};
+
+enum {
+ REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
+ REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
+ REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
+ REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
+ REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
+ REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
+
+ REQ_F_LINK_HEAD_BIT,
+ REQ_F_FAIL_LINK_BIT,
+ REQ_F_INFLIGHT_BIT,
+ REQ_F_CUR_POS_BIT,
+ REQ_F_NOWAIT_BIT,
+ REQ_F_LINK_TIMEOUT_BIT,
+ REQ_F_ISREG_BIT,
+ REQ_F_NEED_CLEANUP_BIT,
+ REQ_F_POLLED_BIT,
+ REQ_F_BUFFER_SELECTED_BIT,
+ REQ_F_NO_FILE_TABLE_BIT,
+ REQ_F_WORK_INITIALIZED_BIT,
+ REQ_F_LTIMEOUT_ACTIVE_BIT,
+
+ /* not a real bit, just to check we're not overflowing the space */
+ __REQ_F_LAST_BIT,
+};
+
+enum {
+ /* ctx owns file */
+ REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
+ /* drain existing IO first */
+ REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
+ /* linked sqes */
+ REQ_F_LINK = BIT(REQ_F_LINK_BIT),
+ /* doesn't sever on completion < 0 */
+ REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
+ /* IOSQE_ASYNC */
+ REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
+ /* IOSQE_BUFFER_SELECT */
+ REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
+
+ /* head of a link */
+ REQ_F_LINK_HEAD = BIT(REQ_F_LINK_HEAD_BIT),
+ /* fail rest of links */
+ REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT),
+ /* on inflight list */
+ REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
+ /* read/write uses file position */
+ REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
+ /* must not punt to workers */
+ REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
+ /* has or had linked timeout */
+ REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
+ /* regular file */
+ REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
+ /* needs cleanup */
+ REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
+ /* already went through poll handler */
+ REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
+ /* buffer already selected */
+ REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
+ /* doesn't need file table for this request */
+ REQ_F_NO_FILE_TABLE = BIT(REQ_F_NO_FILE_TABLE_BIT),
+ /* io_wq_work is initialized */
+ REQ_F_WORK_INITIALIZED = BIT(REQ_F_WORK_INITIALIZED_BIT),
+ /* linked timeout is active, i.e. prepared by link's head */
+ REQ_F_LTIMEOUT_ACTIVE = BIT(REQ_F_LTIMEOUT_ACTIVE_BIT),
+};
+
+struct async_poll {
+ struct io_poll_iocb poll;
+ struct io_poll_iocb *double_poll;
};
/*
@@ -309,49 +651,73 @@
struct io_kiocb {
union {
struct file *file;
- struct kiocb rw;
+ struct io_rw rw;
struct io_poll_iocb poll;
+ struct io_accept accept;
+ struct io_sync sync;
+ struct io_cancel cancel;
struct io_timeout timeout;
+ struct io_timeout_rem timeout_rem;
+ struct io_connect connect;
+ struct io_sr_msg sr_msg;
+ struct io_open open;
+ struct io_close close;
+ struct io_files_update files_update;
+ struct io_fadvise fadvise;
+ struct io_madvise madvise;
+ struct io_epoll epoll;
+ struct io_splice splice;
+ struct io_provide_buf pbuf;
+ struct io_statx statx;
+ /* use only after cleaning per-op data, see io_clean_op() */
+ struct io_completion compl;
};
- struct sqe_submit submit;
+ /* opcode allocated if it needs to store data for async defer */
+ void *async_data;
+ u8 opcode;
+ /* polled IO has completed */
+ u8 iopoll_completed;
- struct io_ring_ctx *ctx;
- struct list_head list;
- struct list_head link_list;
- unsigned int flags;
- refcount_t refs;
-#define REQ_F_NOWAIT 1 /* must not punt to workers */
-#define REQ_F_IOPOLL_COMPLETED 2 /* polled IO has completed */
-#define REQ_F_FIXED_FILE 4 /* ctx owns file */
-#define REQ_F_SEQ_PREV 8 /* sequential with previous */
-#define REQ_F_IO_DRAIN 16 /* drain existing IO first */
-#define REQ_F_IO_DRAINED 32 /* drain done */
-#define REQ_F_LINK 64 /* linked sqes */
-#define REQ_F_LINK_DONE 128 /* linked sqes done */
-#define REQ_F_FAIL_LINK 256 /* fail rest of links */
-#define REQ_F_SHADOW_DRAIN 512 /* link-drain shadow req */
-#define REQ_F_TIMEOUT 1024 /* timeout request */
-#define REQ_F_ISREG 2048 /* regular file */
-#define REQ_F_MUST_PUNT 4096 /* must be punted even for NONBLOCK */
-#define REQ_F_TIMEOUT_NOSEQ 8192 /* no timeout sequence */
-#define REQ_F_CANCEL 16384 /* cancel request */
- unsigned long fsize;
- u64 user_data;
- u32 result;
- u32 sequence;
- struct files_struct *files;
+ u16 buf_index;
+ u32 result;
- struct fs_struct *fs;
+ struct io_ring_ctx *ctx;
+ unsigned int flags;
+ refcount_t refs;
+ struct task_struct *task;
+ u64 user_data;
- struct work_struct work;
- struct task_struct *work_task;
- struct list_head task_list;
+ struct list_head link_list;
+
+ /*
+ * 1. used with ctx->iopoll_list with reads/writes
+ * 2. to track reqs with ->files (see io_op_def::file_table)
+ */
+ struct list_head inflight_entry;
+
+ struct percpu_ref *fixed_file_refs;
+ struct callback_head task_work;
+ /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
+ struct hlist_node hash_node;
+ struct async_poll *apoll;
+ struct io_wq_work work;
};
-#define IO_PLUG_THRESHOLD 2
+struct io_defer_entry {
+ struct list_head list;
+ struct io_kiocb *req;
+ u32 seq;
+};
+
#define IO_IOPOLL_BATCH 8
+struct io_comp_state {
+ unsigned int nr;
+ struct list_head list;
+ struct io_ring_ctx *ctx;
+};
+
struct io_submit_state {
struct blk_plug plug;
@@ -359,8 +725,12 @@
* io_kiocb alloc cache
*/
void *reqs[IO_IOPOLL_BATCH];
- unsigned int free_reqs;
- unsigned int cur_req;
+ unsigned int free_reqs;
+
+ /*
+ * Batch completion logic
+ */
+ struct io_comp_state comp;
/*
* File reference cache
@@ -368,14 +738,242 @@
struct file *file;
unsigned int fd;
unsigned int has_refs;
- unsigned int used_refs;
unsigned int ios_left;
};
-static void io_sq_wq_submit_work(struct work_struct *work);
-static void io_cqring_fill_event(struct io_ring_ctx *ctx, u64 ki_user_data,
- long res);
-static void __io_free_req(struct io_kiocb *req);
+struct io_op_def {
+ /* needs req->file assigned */
+ unsigned needs_file : 1;
+ /* don't fail if file grab fails */
+ unsigned needs_file_no_error : 1;
+ /* hash wq insertion if file is a regular file */
+ unsigned hash_reg_file : 1;
+ /* unbound wq insertion if file is a non-regular file */
+ unsigned unbound_nonreg_file : 1;
+ /* opcode is not supported by this kernel */
+ unsigned not_supported : 1;
+ /* set if opcode supports polled "wait" */
+ unsigned pollin : 1;
+ unsigned pollout : 1;
+ /* op supports buffer selection */
+ unsigned buffer_select : 1;
+ /* must always have async data allocated */
+ unsigned needs_async_data : 1;
+ /* size of async data needed, if any */
+ unsigned short async_size;
+ unsigned work_flags;
+};
+
+static const struct io_op_def io_op_defs[] = {
+ [IORING_OP_NOP] = {},
+ [IORING_OP_READV] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollin = 1,
+ .buffer_select = 1,
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_async_rw),
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_WRITEV] = {
+ .needs_file = 1,
+ .hash_reg_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollout = 1,
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_async_rw),
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
+ IO_WQ_WORK_FSIZE,
+ },
+ [IORING_OP_FSYNC] = {
+ .needs_file = 1,
+ .work_flags = IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_READ_FIXED] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollin = 1,
+ .async_size = sizeof(struct io_async_rw),
+ .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_MM,
+ },
+ [IORING_OP_WRITE_FIXED] = {
+ .needs_file = 1,
+ .hash_reg_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollout = 1,
+ .async_size = sizeof(struct io_async_rw),
+ .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FSIZE |
+ IO_WQ_WORK_MM,
+ },
+ [IORING_OP_POLL_ADD] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ },
+ [IORING_OP_POLL_REMOVE] = {},
+ [IORING_OP_SYNC_FILE_RANGE] = {
+ .needs_file = 1,
+ .work_flags = IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_SENDMSG] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollout = 1,
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_async_msghdr),
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
+ IO_WQ_WORK_FS,
+ },
+ [IORING_OP_RECVMSG] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollin = 1,
+ .buffer_select = 1,
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_async_msghdr),
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
+ IO_WQ_WORK_FS,
+ },
+ [IORING_OP_TIMEOUT] = {
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_timeout_data),
+ .work_flags = IO_WQ_WORK_MM,
+ },
+ [IORING_OP_TIMEOUT_REMOVE] = {},
+ [IORING_OP_ACCEPT] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollin = 1,
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_FILES,
+ },
+ [IORING_OP_ASYNC_CANCEL] = {},
+ [IORING_OP_LINK_TIMEOUT] = {
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_timeout_data),
+ .work_flags = IO_WQ_WORK_MM,
+ },
+ [IORING_OP_CONNECT] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollout = 1,
+ .needs_async_data = 1,
+ .async_size = sizeof(struct io_async_connect),
+ .work_flags = IO_WQ_WORK_MM,
+ },
+ [IORING_OP_FALLOCATE] = {
+ .needs_file = 1,
+ .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FSIZE,
+ },
+ [IORING_OP_OPENAT] = {
+ .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_BLKCG |
+ IO_WQ_WORK_FS,
+ },
+ [IORING_OP_CLOSE] = {
+ .needs_file = 1,
+ .needs_file_no_error = 1,
+ .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_FILES_UPDATE] = {
+ .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_MM,
+ },
+ [IORING_OP_STATX] = {
+ .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_MM |
+ IO_WQ_WORK_FS | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_READ] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollin = 1,
+ .buffer_select = 1,
+ .async_size = sizeof(struct io_async_rw),
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_WRITE] = {
+ .needs_file = 1,
+ .hash_reg_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollout = 1,
+ .async_size = sizeof(struct io_async_rw),
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
+ IO_WQ_WORK_FSIZE,
+ },
+ [IORING_OP_FADVISE] = {
+ .needs_file = 1,
+ .work_flags = IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_MADVISE] = {
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_SEND] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollout = 1,
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_RECV] = {
+ .needs_file = 1,
+ .unbound_nonreg_file = 1,
+ .pollin = 1,
+ .buffer_select = 1,
+ .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_OPENAT2] = {
+ .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_FS |
+ IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_EPOLL_CTL] = {
+ .unbound_nonreg_file = 1,
+ .work_flags = IO_WQ_WORK_FILES,
+ },
+ [IORING_OP_SPLICE] = {
+ .needs_file = 1,
+ .hash_reg_file = 1,
+ .unbound_nonreg_file = 1,
+ .work_flags = IO_WQ_WORK_BLKCG,
+ },
+ [IORING_OP_PROVIDE_BUFFERS] = {},
+ [IORING_OP_REMOVE_BUFFERS] = {},
+ [IORING_OP_TEE] = {
+ .needs_file = 1,
+ .hash_reg_file = 1,
+ .unbound_nonreg_file = 1,
+ },
+};
+
+enum io_mem_account {
+ ACCT_LOCKED,
+ ACCT_PINNED,
+};
+
+static void destroy_fixed_file_ref_node(struct fixed_file_ref_node *ref_node);
+static struct fixed_file_ref_node *alloc_fixed_file_ref_node(
+ struct io_ring_ctx *ctx);
+
+static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
+ struct io_comp_state *cs);
+static void io_cqring_fill_event(struct io_kiocb *req, long res);
+static void io_put_req(struct io_kiocb *req);
+static void io_put_req_deferred(struct io_kiocb *req, int nr);
+static void io_double_put_req(struct io_kiocb *req);
+static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req);
+static void __io_queue_linked_timeout(struct io_kiocb *req);
+static void io_queue_linked_timeout(struct io_kiocb *req);
+static int __io_sqe_files_update(struct io_ring_ctx *ctx,
+ struct io_uring_files_update *ip,
+ unsigned nr_args);
+static void __io_clean_op(struct io_kiocb *req);
+static struct file *io_file_get(struct io_submit_state *state,
+ struct io_kiocb *req, int fd, bool fixed);
+static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs);
+static void io_file_put_work(struct work_struct *work);
+
+static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
+ struct iovec **iovec, struct iov_iter *iter,
+ bool needs_lock);
+static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
+ const struct iovec *fast_iov,
+ struct iov_iter *iter, bool force);
+static void io_req_drop_files(struct io_kiocb *req);
+static void io_req_task_queue(struct io_kiocb *req);
static struct kmem_cache *req_cachep;
@@ -394,179 +992,618 @@
}
EXPORT_SYMBOL(io_uring_get_socket);
+static inline void io_clean_op(struct io_kiocb *req)
+{
+ if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED))
+ __io_clean_op(req);
+}
+
+static inline bool __io_match_files(struct io_kiocb *req,
+ struct files_struct *files)
+{
+ if (req->file && req->file->f_op == &io_uring_fops)
+ return true;
+
+ return ((req->flags & REQ_F_WORK_INITIALIZED) &&
+ (req->work.flags & IO_WQ_WORK_FILES)) &&
+ req->work.identity->files == files;
+}
+
+static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
+{
+ bool got = percpu_ref_tryget(ref);
+
+ /* already at zero, wait for ->release() */
+ if (!got)
+ wait_for_completion(compl);
+ percpu_ref_resurrect(ref);
+ if (got)
+ percpu_ref_put(ref);
+}
+
+static bool io_match_task(struct io_kiocb *head,
+ struct task_struct *task,
+ struct files_struct *files)
+{
+ struct io_kiocb *link;
+
+ if (task && head->task != task) {
+ /* in terms of cancelation, always match if req task is dead */
+ if (head->task->flags & PF_EXITING)
+ return true;
+ return false;
+ }
+ if (!files)
+ return true;
+ if (__io_match_files(head, files))
+ return true;
+ if (head->flags & REQ_F_LINK_HEAD) {
+ list_for_each_entry(link, &head->link_list, link_list) {
+ if (__io_match_files(link, files))
+ return true;
+ }
+ }
+ return false;
+}
+
+
+static void io_sq_thread_drop_mm(void)
+{
+ struct mm_struct *mm = current->mm;
+
+ if (mm) {
+ kthread_unuse_mm(mm);
+ mmput(mm);
+ current->mm = NULL;
+ }
+}
+
+static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx)
+{
+ struct mm_struct *mm;
+
+ if (current->flags & PF_EXITING)
+ return -EFAULT;
+ if (current->mm)
+ return 0;
+
+ /* Should never happen */
+ if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL)))
+ return -EFAULT;
+
+ task_lock(ctx->sqo_task);
+ mm = ctx->sqo_task->mm;
+ if (unlikely(!mm || !mmget_not_zero(mm)))
+ mm = NULL;
+ task_unlock(ctx->sqo_task);
+
+ if (mm) {
+ kthread_use_mm(mm);
+ return 0;
+ }
+
+ return -EFAULT;
+}
+
+static int io_sq_thread_acquire_mm(struct io_ring_ctx *ctx,
+ struct io_kiocb *req)
+{
+ if (!(io_op_defs[req->opcode].work_flags & IO_WQ_WORK_MM))
+ return 0;
+ return __io_sq_thread_acquire_mm(ctx);
+}
+
+static void io_sq_thread_associate_blkcg(struct io_ring_ctx *ctx,
+ struct cgroup_subsys_state **cur_css)
+
+{
+#ifdef CONFIG_BLK_CGROUP
+ /* puts the old one when swapping */
+ if (*cur_css != ctx->sqo_blkcg_css) {
+ kthread_associate_blkcg(ctx->sqo_blkcg_css);
+ *cur_css = ctx->sqo_blkcg_css;
+ }
+#endif
+}
+
+static void io_sq_thread_unassociate_blkcg(void)
+{
+#ifdef CONFIG_BLK_CGROUP
+ kthread_associate_blkcg(NULL);
+#endif
+}
+
+static inline void req_set_fail_links(struct io_kiocb *req)
+{
+ if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK)
+ req->flags |= REQ_F_FAIL_LINK;
+}
+
+/*
+ * None of these are dereferenced, they are simply used to check if any of
+ * them have changed. If we're under current and check they are still the
+ * same, we're fine to grab references to them for actual out-of-line use.
+ */
+static void io_init_identity(struct io_identity *id)
+{
+ id->files = current->files;
+ id->mm = current->mm;
+#ifdef CONFIG_BLK_CGROUP
+ rcu_read_lock();
+ id->blkcg_css = blkcg_css();
+ rcu_read_unlock();
+#endif
+ id->creds = current_cred();
+ id->nsproxy = current->nsproxy;
+ id->fs = current->fs;
+ id->fsize = rlimit(RLIMIT_FSIZE);
+#ifdef CONFIG_AUDIT
+ id->loginuid = current->loginuid;
+ id->sessionid = current->sessionid;
+#endif
+ refcount_set(&id->count, 1);
+}
+
+static inline void __io_req_init_async(struct io_kiocb *req)
+{
+ memset(&req->work, 0, sizeof(req->work));
+ req->flags |= REQ_F_WORK_INITIALIZED;
+}
+
+/*
+ * Note: must call io_req_init_async() for the first time you
+ * touch any members of io_wq_work.
+ */
+static inline void io_req_init_async(struct io_kiocb *req)
+{
+ struct io_uring_task *tctx = current->io_uring;
+
+ if (req->flags & REQ_F_WORK_INITIALIZED)
+ return;
+
+ __io_req_init_async(req);
+
+ /* Grab a ref if this isn't our static identity */
+ req->work.identity = tctx->identity;
+ if (tctx->identity != &tctx->__identity)
+ refcount_inc(&req->work.identity->count);
+}
+
+static inline bool io_async_submit(struct io_ring_ctx *ctx)
+{
+ return ctx->flags & IORING_SETUP_SQPOLL;
+}
+
static void io_ring_ctx_ref_free(struct percpu_ref *ref)
{
struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
- complete(&ctx->ctx_done);
+ complete(&ctx->ref_comp);
+}
+
+static inline bool io_is_timeout_noseq(struct io_kiocb *req)
+{
+ return !req->timeout.off;
}
static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
{
struct io_ring_ctx *ctx;
- int i;
+ int hash_bits;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return NULL;
+ ctx->fallback_req = kmem_cache_alloc(req_cachep, GFP_KERNEL);
+ if (!ctx->fallback_req)
+ goto err;
+
+ /*
+ * Use 5 bits less than the max cq entries, that should give us around
+ * 32 entries per hash list if totally full and uniformly spread.
+ */
+ hash_bits = ilog2(p->cq_entries);
+ hash_bits -= 5;
+ if (hash_bits <= 0)
+ hash_bits = 1;
+ ctx->cancel_hash_bits = hash_bits;
+ ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
+ GFP_KERNEL);
+ if (!ctx->cancel_hash)
+ goto err;
+ __hash_init(ctx->cancel_hash, 1U << hash_bits);
+
if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
- PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
- kfree(ctx);
- return NULL;
- }
+ PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
+ goto err;
ctx->flags = p->flags;
- init_waitqueue_head(&ctx->sqo_wait);
+ init_waitqueue_head(&ctx->sqo_sq_wait);
+ INIT_LIST_HEAD(&ctx->sqd_list);
init_waitqueue_head(&ctx->cq_wait);
- init_completion(&ctx->ctx_done);
- init_completion(&ctx->sqo_thread_started);
+ INIT_LIST_HEAD(&ctx->cq_overflow_list);
+ init_completion(&ctx->ref_comp);
+ init_completion(&ctx->sq_thread_comp);
+ xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
+ xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
mutex_init(&ctx->uring_lock);
init_waitqueue_head(&ctx->wait);
- for (i = 0; i < ARRAY_SIZE(ctx->pending_async); i++) {
- spin_lock_init(&ctx->pending_async[i].lock);
- INIT_LIST_HEAD(&ctx->pending_async[i].list);
- atomic_set(&ctx->pending_async[i].cnt, 0);
- }
spin_lock_init(&ctx->completion_lock);
- INIT_LIST_HEAD(&ctx->poll_list);
- INIT_LIST_HEAD(&ctx->cancel_list);
+ INIT_LIST_HEAD(&ctx->iopoll_list);
INIT_LIST_HEAD(&ctx->defer_list);
INIT_LIST_HEAD(&ctx->timeout_list);
- INIT_LIST_HEAD(&ctx->task_list);
- spin_lock_init(&ctx->task_lock);
+ spin_lock_init(&ctx->inflight_lock);
+ INIT_LIST_HEAD(&ctx->inflight_list);
+ INIT_DELAYED_WORK(&ctx->file_put_work, io_file_put_work);
+ init_llist_head(&ctx->file_put_llist);
return ctx;
-}
-
-static inline bool __io_sequence_defer(struct io_ring_ctx *ctx,
- struct io_kiocb *req)
-{
- return req->sequence != ctx->cached_cq_tail + ctx->cached_sq_dropped
- + atomic_read(&ctx->cached_cq_overflow);
-}
-
-static inline bool io_sequence_defer(struct io_ring_ctx *ctx,
- struct io_kiocb *req)
-{
- if ((req->flags & (REQ_F_IO_DRAIN|REQ_F_IO_DRAINED)) != REQ_F_IO_DRAIN)
- return false;
-
- return __io_sequence_defer(ctx, req);
-}
-
-static struct io_kiocb *io_get_deferred_req(struct io_ring_ctx *ctx)
-{
- struct io_kiocb *req;
-
- req = list_first_entry_or_null(&ctx->defer_list, struct io_kiocb, list);
- if (req && !io_sequence_defer(ctx, req)) {
- list_del_init(&req->list);
- return req;
- }
-
+err:
+ if (ctx->fallback_req)
+ kmem_cache_free(req_cachep, ctx->fallback_req);
+ kfree(ctx->cancel_hash);
+ kfree(ctx);
return NULL;
}
-static struct io_kiocb *io_get_timeout_req(struct io_ring_ctx *ctx)
+static bool req_need_defer(struct io_kiocb *req, u32 seq)
{
- struct io_kiocb *req;
+ if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
+ struct io_ring_ctx *ctx = req->ctx;
- req = list_first_entry_or_null(&ctx->timeout_list, struct io_kiocb, list);
- if (req) {
- if (req->flags & REQ_F_TIMEOUT_NOSEQ)
- return NULL;
- if (!__io_sequence_defer(ctx, req)) {
- list_del_init(&req->list);
- return req;
- }
+ return seq != ctx->cached_cq_tail
+ + READ_ONCE(ctx->cached_cq_overflow);
}
- return NULL;
+ return false;
}
static void __io_commit_cqring(struct io_ring_ctx *ctx)
{
struct io_rings *rings = ctx->rings;
- if (ctx->cached_cq_tail != READ_ONCE(rings->cq.tail)) {
- /* order cqe stores with ring update */
- smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
-
- if (wq_has_sleeper(&ctx->cq_wait)) {
- wake_up_interruptible(&ctx->cq_wait);
- kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
- }
- }
+ /* order cqe stores with ring update */
+ smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
}
-static inline void io_queue_async_work(struct io_ring_ctx *ctx,
- struct io_kiocb *req)
+static void io_put_identity(struct io_uring_task *tctx, struct io_kiocb *req)
{
- unsigned long flags;
- int rw = 0;
-
- if (req->submit.sqe) {
- switch (req->submit.opcode) {
- case IORING_OP_WRITEV:
- case IORING_OP_WRITE_FIXED:
- rw = !(req->rw.ki_flags & IOCB_DIRECT);
- break;
- }
- }
-
- if (req->work.func == io_sq_wq_submit_work) {
- req->files = current->files;
-
- spin_lock_irqsave(&ctx->task_lock, flags);
- list_add(&req->task_list, &ctx->task_list);
- req->work_task = NULL;
- spin_unlock_irqrestore(&ctx->task_lock, flags);
- }
-
- queue_work(ctx->sqo_wq[rw], &req->work);
+ if (req->work.identity == &tctx->__identity)
+ return;
+ if (refcount_dec_and_test(&req->work.identity->count))
+ kfree(req->work.identity);
}
-static void io_kill_timeout(struct io_kiocb *req)
+static void io_req_clean_work(struct io_kiocb *req)
{
+ if (!(req->flags & REQ_F_WORK_INITIALIZED))
+ return;
+
+ req->flags &= ~REQ_F_WORK_INITIALIZED;
+
+ if (req->work.flags & IO_WQ_WORK_MM) {
+ mmdrop(req->work.identity->mm);
+ req->work.flags &= ~IO_WQ_WORK_MM;
+ }
+#ifdef CONFIG_BLK_CGROUP
+ if (req->work.flags & IO_WQ_WORK_BLKCG) {
+ css_put(req->work.identity->blkcg_css);
+ req->work.flags &= ~IO_WQ_WORK_BLKCG;
+ }
+#endif
+ if (req->work.flags & IO_WQ_WORK_CREDS) {
+ put_cred(req->work.identity->creds);
+ req->work.flags &= ~IO_WQ_WORK_CREDS;
+ }
+ if (req->work.flags & IO_WQ_WORK_FS) {
+ struct fs_struct *fs = req->work.identity->fs;
+
+ spin_lock(&req->work.identity->fs->lock);
+ if (--fs->users)
+ fs = NULL;
+ spin_unlock(&req->work.identity->fs->lock);
+ if (fs)
+ free_fs_struct(fs);
+ req->work.flags &= ~IO_WQ_WORK_FS;
+ }
+ if (req->flags & REQ_F_INFLIGHT)
+ io_req_drop_files(req);
+
+ io_put_identity(req->task->io_uring, req);
+}
+
+/*
+ * Create a private copy of io_identity, since some fields don't match
+ * the current context.
+ */
+static bool io_identity_cow(struct io_kiocb *req)
+{
+ struct io_uring_task *tctx = current->io_uring;
+ const struct cred *creds = NULL;
+ struct io_identity *id;
+
+ if (req->work.flags & IO_WQ_WORK_CREDS)
+ creds = req->work.identity->creds;
+
+ id = kmemdup(req->work.identity, sizeof(*id), GFP_KERNEL);
+ if (unlikely(!id)) {
+ req->work.flags |= IO_WQ_WORK_CANCEL;
+ return false;
+ }
+
+ /*
+ * We can safely just re-init the creds we copied Either the field
+ * matches the current one, or we haven't grabbed it yet. The only
+ * exception is ->creds, through registered personalities, so handle
+ * that one separately.
+ */
+ io_init_identity(id);
+ if (creds)
+ id->creds = creds;
+
+ /* add one for this request */
+ refcount_inc(&id->count);
+
+ /* drop tctx and req identity references, if needed */
+ if (tctx->identity != &tctx->__identity &&
+ refcount_dec_and_test(&tctx->identity->count))
+ kfree(tctx->identity);
+ if (req->work.identity != &tctx->__identity &&
+ refcount_dec_and_test(&req->work.identity->count))
+ kfree(req->work.identity);
+
+ req->work.identity = id;
+ tctx->identity = id;
+ return true;
+}
+
+static bool io_grab_identity(struct io_kiocb *req)
+{
+ const struct io_op_def *def = &io_op_defs[req->opcode];
+ struct io_identity *id = req->work.identity;
+ struct io_ring_ctx *ctx = req->ctx;
+
+ if (def->work_flags & IO_WQ_WORK_FSIZE) {
+ if (id->fsize != rlimit(RLIMIT_FSIZE))
+ return false;
+ req->work.flags |= IO_WQ_WORK_FSIZE;
+ }
+#ifdef CONFIG_BLK_CGROUP
+ if (!(req->work.flags & IO_WQ_WORK_BLKCG) &&
+ (def->work_flags & IO_WQ_WORK_BLKCG)) {
+ rcu_read_lock();
+ if (id->blkcg_css != blkcg_css()) {
+ rcu_read_unlock();
+ return false;
+ }
+ /*
+ * This should be rare, either the cgroup is dying or the task
+ * is moving cgroups. Just punt to root for the handful of ios.
+ */
+ if (css_tryget_online(id->blkcg_css))
+ req->work.flags |= IO_WQ_WORK_BLKCG;
+ rcu_read_unlock();
+ }
+#endif
+ if (!(req->work.flags & IO_WQ_WORK_CREDS)) {
+ if (id->creds != current_cred())
+ return false;
+ get_cred(id->creds);
+ req->work.flags |= IO_WQ_WORK_CREDS;
+ }
+#ifdef CONFIG_AUDIT
+ if (!uid_eq(current->loginuid, id->loginuid) ||
+ current->sessionid != id->sessionid)
+ return false;
+#endif
+ if (!(req->work.flags & IO_WQ_WORK_FS) &&
+ (def->work_flags & IO_WQ_WORK_FS)) {
+ if (current->fs != id->fs)
+ return false;
+ spin_lock(&id->fs->lock);
+ if (!id->fs->in_exec) {
+ id->fs->users++;
+ req->work.flags |= IO_WQ_WORK_FS;
+ } else {
+ req->work.flags |= IO_WQ_WORK_CANCEL;
+ }
+ spin_unlock(¤t->fs->lock);
+ }
+ if (!(req->work.flags & IO_WQ_WORK_FILES) &&
+ (def->work_flags & IO_WQ_WORK_FILES) &&
+ !(req->flags & REQ_F_NO_FILE_TABLE)) {
+ if (id->files != current->files ||
+ id->nsproxy != current->nsproxy)
+ return false;
+ atomic_inc(&id->files->count);
+ get_nsproxy(id->nsproxy);
+
+ if (!(req->flags & REQ_F_INFLIGHT)) {
+ req->flags |= REQ_F_INFLIGHT;
+
+ spin_lock_irq(&ctx->inflight_lock);
+ list_add(&req->inflight_entry, &ctx->inflight_list);
+ spin_unlock_irq(&ctx->inflight_lock);
+ }
+ req->work.flags |= IO_WQ_WORK_FILES;
+ }
+ if (!(req->work.flags & IO_WQ_WORK_MM) &&
+ (def->work_flags & IO_WQ_WORK_MM)) {
+ if (id->mm != current->mm)
+ return false;
+ mmgrab(id->mm);
+ req->work.flags |= IO_WQ_WORK_MM;
+ }
+
+ return true;
+}
+
+static void io_prep_async_work(struct io_kiocb *req)
+{
+ const struct io_op_def *def = &io_op_defs[req->opcode];
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_identity *id;
+
+ io_req_init_async(req);
+ id = req->work.identity;
+
+ if (req->flags & REQ_F_FORCE_ASYNC)
+ req->work.flags |= IO_WQ_WORK_CONCURRENT;
+
+ if (req->flags & REQ_F_ISREG) {
+ if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
+ io_wq_hash_work(&req->work, file_inode(req->file));
+ } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
+ if (def->unbound_nonreg_file)
+ req->work.flags |= IO_WQ_WORK_UNBOUND;
+ }
+
+ /* if we fail grabbing identity, we must COW, regrab, and retry */
+ if (io_grab_identity(req))
+ return;
+
+ if (!io_identity_cow(req))
+ return;
+
+ /* can't fail at this point */
+ if (!io_grab_identity(req))
+ WARN_ON(1);
+}
+
+static void io_prep_async_link(struct io_kiocb *req)
+{
+ struct io_kiocb *cur;
+
+ io_prep_async_work(req);
+ if (req->flags & REQ_F_LINK_HEAD)
+ list_for_each_entry(cur, &req->link_list, link_list)
+ io_prep_async_work(cur);
+}
+
+static struct io_kiocb *__io_queue_async_work(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_kiocb *link = io_prep_linked_timeout(req);
+
+ trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
+ &req->work, req->flags);
+ io_wq_enqueue(ctx->io_wq, &req->work);
+ return link;
+}
+
+static void io_queue_async_work(struct io_kiocb *req)
+{
+ struct io_kiocb *link;
+
+ /* init ->work of the whole link before punting */
+ io_prep_async_link(req);
+ link = __io_queue_async_work(req);
+
+ if (link)
+ io_queue_linked_timeout(link);
+}
+
+static void io_kill_timeout(struct io_kiocb *req, int status)
+{
+ struct io_timeout_data *io = req->async_data;
int ret;
- ret = hrtimer_try_to_cancel(&req->timeout.timer);
+ ret = hrtimer_try_to_cancel(&io->timer);
if (ret != -1) {
- atomic_inc(&req->ctx->cq_timeouts);
- list_del(&req->list);
- io_cqring_fill_event(req->ctx, req->user_data, 0);
- __io_free_req(req);
+ if (status)
+ req_set_fail_links(req);
+ atomic_set(&req->ctx->cq_timeouts,
+ atomic_read(&req->ctx->cq_timeouts) + 1);
+ list_del_init(&req->timeout.list);
+ io_cqring_fill_event(req, status);
+ io_put_req_deferred(req, 1);
}
}
-static void io_kill_timeouts(struct io_ring_ctx *ctx)
+/*
+ * Returns true if we found and killed one or more timeouts
+ */
+static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
+ struct files_struct *files)
{
struct io_kiocb *req, *tmp;
+ int canceled = 0;
spin_lock_irq(&ctx->completion_lock);
- list_for_each_entry_safe(req, tmp, &ctx->timeout_list, list)
- io_kill_timeout(req);
+ list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
+ if (io_match_task(req, tsk, files)) {
+ io_kill_timeout(req, -ECANCELED);
+ canceled++;
+ }
+ }
spin_unlock_irq(&ctx->completion_lock);
+ return canceled != 0;
+}
+
+static void __io_queue_deferred(struct io_ring_ctx *ctx)
+{
+ do {
+ struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
+ struct io_defer_entry, list);
+
+ if (req_need_defer(de->req, de->seq))
+ break;
+ list_del_init(&de->list);
+ io_req_task_queue(de->req);
+ kfree(de);
+ } while (!list_empty(&ctx->defer_list));
+}
+
+static void io_flush_timeouts(struct io_ring_ctx *ctx)
+{
+ u32 seq;
+
+ if (list_empty(&ctx->timeout_list))
+ return;
+
+ seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
+
+ do {
+ u32 events_needed, events_got;
+ struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
+ struct io_kiocb, timeout.list);
+
+ if (io_is_timeout_noseq(req))
+ break;
+
+ /*
+ * Since seq can easily wrap around over time, subtract
+ * the last seq at which timeouts were flushed before comparing.
+ * Assuming not more than 2^31-1 events have happened since,
+ * these subtractions won't have wrapped, so we can check if
+ * target is in [last_seq, current_seq] by comparing the two.
+ */
+ events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
+ events_got = seq - ctx->cq_last_tm_flush;
+ if (events_got < events_needed)
+ break;
+
+ list_del_init(&req->timeout.list);
+ io_kill_timeout(req, 0);
+ } while (!list_empty(&ctx->timeout_list));
+
+ ctx->cq_last_tm_flush = seq;
}
static void io_commit_cqring(struct io_ring_ctx *ctx)
{
- struct io_kiocb *req;
-
- while ((req = io_get_timeout_req(ctx)) != NULL)
- io_kill_timeout(req);
-
+ io_flush_timeouts(ctx);
__io_commit_cqring(ctx);
- while ((req = io_get_deferred_req(ctx)) != NULL) {
- if (req->flags & REQ_F_SHADOW_DRAIN) {
- /* Just for drain, free it. */
- __io_free_req(req);
- continue;
- }
- req->flags |= REQ_F_IO_DRAINED;
- io_queue_async_work(ctx, req);
- }
+ if (unlikely(!list_empty(&ctx->defer_list)))
+ __io_queue_deferred(ctx);
+}
+
+static inline bool io_sqring_full(struct io_ring_ctx *ctx)
+{
+ struct io_rings *r = ctx->rings;
+
+ return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == r->sq_ring_entries;
}
static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx)
@@ -587,10 +1624,116 @@
return &rings->cqes[tail & ctx->cq_mask];
}
-static void io_cqring_fill_event(struct io_ring_ctx *ctx, u64 ki_user_data,
- long res)
+static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
{
+ if (!ctx->cq_ev_fd)
+ return false;
+ if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
+ return false;
+ if (!ctx->eventfd_async)
+ return true;
+ return io_wq_current_is_worker();
+}
+
+static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
+{
+ if (wq_has_sleeper(&ctx->cq_wait)) {
+ wake_up_interruptible(&ctx->cq_wait);
+ kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
+ }
+ if (waitqueue_active(&ctx->wait))
+ wake_up(&ctx->wait);
+ if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
+ wake_up(&ctx->sq_data->wait);
+ if (io_should_trigger_evfd(ctx))
+ eventfd_signal(ctx->cq_ev_fd, 1);
+}
+
+static void io_cqring_mark_overflow(struct io_ring_ctx *ctx)
+{
+ if (list_empty(&ctx->cq_overflow_list)) {
+ clear_bit(0, &ctx->sq_check_overflow);
+ clear_bit(0, &ctx->cq_check_overflow);
+ ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW;
+ }
+}
+
+/* Returns true if there are no backlogged entries after the flush */
+static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
+ struct task_struct *tsk,
+ struct files_struct *files)
+{
+ struct io_rings *rings = ctx->rings;
+ struct io_kiocb *req, *tmp;
struct io_uring_cqe *cqe;
+ unsigned long flags;
+ LIST_HEAD(list);
+
+ if (!force) {
+ if ((ctx->cached_cq_tail - READ_ONCE(rings->cq.head) ==
+ rings->cq_ring_entries))
+ return false;
+ }
+
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+
+ cqe = NULL;
+ list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) {
+ if (!io_match_task(req, tsk, files))
+ continue;
+
+ cqe = io_get_cqring(ctx);
+ if (!cqe && !force)
+ break;
+
+ list_move(&req->compl.list, &list);
+ if (cqe) {
+ WRITE_ONCE(cqe->user_data, req->user_data);
+ WRITE_ONCE(cqe->res, req->result);
+ WRITE_ONCE(cqe->flags, req->compl.cflags);
+ } else {
+ ctx->cached_cq_overflow++;
+ WRITE_ONCE(ctx->rings->cq_overflow,
+ ctx->cached_cq_overflow);
+ }
+ }
+
+ io_commit_cqring(ctx);
+ io_cqring_mark_overflow(ctx);
+
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+ io_cqring_ev_posted(ctx);
+
+ while (!list_empty(&list)) {
+ req = list_first_entry(&list, struct io_kiocb, compl.list);
+ list_del(&req->compl.list);
+ io_put_req(req);
+ }
+
+ return cqe != NULL;
+}
+
+static void io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
+ struct task_struct *tsk,
+ struct files_struct *files)
+{
+ if (test_bit(0, &ctx->cq_check_overflow)) {
+ /* iopoll syncs against uring_lock, not completion_lock */
+ if (ctx->flags & IORING_SETUP_IOPOLL)
+ mutex_lock(&ctx->uring_lock);
+ __io_cqring_overflow_flush(ctx, force, tsk, files);
+ if (ctx->flags & IORING_SETUP_IOPOLL)
+ mutex_unlock(&ctx->uring_lock);
+ }
+}
+
+static void __io_cqring_fill_event(struct io_kiocb *req, long res,
+ unsigned int cflags)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_uring_cqe *cqe;
+
+ trace_io_uring_complete(ctx, req->user_data, res);
/*
* If we can't get a cq entry, userspace overflowed the
@@ -598,53 +1741,127 @@
* the ring.
*/
cqe = io_get_cqring(ctx);
- if (cqe) {
- WRITE_ONCE(cqe->user_data, ki_user_data);
+ if (likely(cqe)) {
+ WRITE_ONCE(cqe->user_data, req->user_data);
WRITE_ONCE(cqe->res, res);
- WRITE_ONCE(cqe->flags, 0);
+ WRITE_ONCE(cqe->flags, cflags);
+ } else if (ctx->cq_overflow_flushed ||
+ atomic_read(&req->task->io_uring->in_idle)) {
+ /*
+ * If we're in ring overflow flush mode, or in task cancel mode,
+ * then we cannot store the request for later flushing, we need
+ * to drop it on the floor.
+ */
+ ctx->cached_cq_overflow++;
+ WRITE_ONCE(ctx->rings->cq_overflow, ctx->cached_cq_overflow);
} else {
- WRITE_ONCE(ctx->rings->cq_overflow,
- atomic_inc_return(&ctx->cached_cq_overflow));
+ if (list_empty(&ctx->cq_overflow_list)) {
+ set_bit(0, &ctx->sq_check_overflow);
+ set_bit(0, &ctx->cq_check_overflow);
+ ctx->rings->sq_flags |= IORING_SQ_CQ_OVERFLOW;
+ }
+ io_clean_op(req);
+ req->result = res;
+ req->compl.cflags = cflags;
+ refcount_inc(&req->refs);
+ list_add_tail(&req->compl.list, &ctx->cq_overflow_list);
}
}
-static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
+static void io_cqring_fill_event(struct io_kiocb *req, long res)
{
- if (waitqueue_active(&ctx->wait))
- wake_up(&ctx->wait);
- if (waitqueue_active(&ctx->sqo_wait))
- wake_up(&ctx->sqo_wait);
- if (ctx->cq_ev_fd)
- eventfd_signal(ctx->cq_ev_fd, 1);
+ __io_cqring_fill_event(req, res, 0);
}
-static void io_cqring_add_event(struct io_ring_ctx *ctx, u64 user_data,
- long res)
+static void io_cqring_add_event(struct io_kiocb *req, long res, long cflags)
{
+ struct io_ring_ctx *ctx = req->ctx;
unsigned long flags;
spin_lock_irqsave(&ctx->completion_lock, flags);
- io_cqring_fill_event(ctx, user_data, res);
+ __io_cqring_fill_event(req, res, cflags);
io_commit_cqring(ctx);
spin_unlock_irqrestore(&ctx->completion_lock, flags);
io_cqring_ev_posted(ctx);
}
-static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx,
- struct io_submit_state *state)
+static void io_submit_flush_completions(struct io_comp_state *cs)
{
- gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
+ struct io_ring_ctx *ctx = cs->ctx;
+
+ spin_lock_irq(&ctx->completion_lock);
+ while (!list_empty(&cs->list)) {
+ struct io_kiocb *req;
+
+ req = list_first_entry(&cs->list, struct io_kiocb, compl.list);
+ list_del(&req->compl.list);
+ __io_cqring_fill_event(req, req->result, req->compl.cflags);
+
+ /*
+ * io_free_req() doesn't care about completion_lock unless one
+ * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
+ * because of a potential deadlock with req->work.fs->lock
+ */
+ if (req->flags & (REQ_F_FAIL_LINK|REQ_F_LINK_TIMEOUT
+ |REQ_F_WORK_INITIALIZED)) {
+ spin_unlock_irq(&ctx->completion_lock);
+ io_put_req(req);
+ spin_lock_irq(&ctx->completion_lock);
+ } else {
+ io_put_req(req);
+ }
+ }
+ io_commit_cqring(ctx);
+ spin_unlock_irq(&ctx->completion_lock);
+
+ io_cqring_ev_posted(ctx);
+ cs->nr = 0;
+}
+
+static void __io_req_complete(struct io_kiocb *req, long res, unsigned cflags,
+ struct io_comp_state *cs)
+{
+ if (!cs) {
+ io_cqring_add_event(req, res, cflags);
+ io_put_req(req);
+ } else {
+ io_clean_op(req);
+ req->result = res;
+ req->compl.cflags = cflags;
+ list_add_tail(&req->compl.list, &cs->list);
+ if (++cs->nr >= 32)
+ io_submit_flush_completions(cs);
+ }
+}
+
+static void io_req_complete(struct io_kiocb *req, long res)
+{
+ __io_req_complete(req, res, 0, NULL);
+}
+
+static inline bool io_is_fallback_req(struct io_kiocb *req)
+{
+ return req == (struct io_kiocb *)
+ ((unsigned long) req->ctx->fallback_req & ~1UL);
+}
+
+static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx)
+{
struct io_kiocb *req;
- if (!percpu_ref_tryget(&ctx->refs))
- return NULL;
+ req = ctx->fallback_req;
+ if (!test_and_set_bit_lock(0, (unsigned long *) &ctx->fallback_req))
+ return req;
- if (!state) {
- req = kmem_cache_alloc(req_cachep, gfp);
- if (unlikely(!req))
- goto out;
- } else if (!state->free_reqs) {
+ return NULL;
+}
+
+static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx,
+ struct io_submit_state *state)
+{
+ if (!state->free_reqs) {
+ gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
size_t sz;
int ret;
@@ -658,50 +1875,94 @@
if (unlikely(ret <= 0)) {
state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
if (!state->reqs[0])
- goto out;
+ goto fallback;
ret = 1;
}
- state->free_reqs = ret - 1;
- state->cur_req = 1;
- req = state->reqs[0];
- } else {
- req = state->reqs[state->cur_req];
- state->free_reqs--;
- state->cur_req++;
+ state->free_reqs = ret;
}
- INIT_LIST_HEAD(&req->task_list);
- req->file = NULL;
- req->ctx = ctx;
- req->flags = 0;
- /* one is dropped after submission, the other at completion */
- refcount_set(&req->refs, 2);
- req->result = 0;
- req->fs = NULL;
- return req;
-out:
- percpu_ref_put(&ctx->refs);
- return NULL;
+ state->free_reqs--;
+ return state->reqs[state->free_reqs];
+fallback:
+ return io_get_fallback_req(ctx);
}
-static void io_free_req_many(struct io_ring_ctx *ctx, void **reqs, int *nr)
+static inline void io_put_file(struct io_kiocb *req, struct file *file,
+ bool fixed)
{
- if (*nr) {
- kmem_cache_free_bulk(req_cachep, *nr, reqs);
- percpu_ref_put_many(&ctx->refs, *nr);
- *nr = 0;
- }
+ if (fixed)
+ percpu_ref_put(req->fixed_file_refs);
+ else
+ fput(file);
+}
+
+static void io_dismantle_req(struct io_kiocb *req)
+{
+ io_clean_op(req);
+
+ if (req->async_data)
+ kfree(req->async_data);
+ if (req->file)
+ io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE));
+
+ io_req_clean_work(req);
}
static void __io_free_req(struct io_kiocb *req)
{
- if (req->file && !(req->flags & REQ_F_FIXED_FILE))
- fput(req->file);
- percpu_ref_put(&req->ctx->refs);
- kmem_cache_free(req_cachep, req);
+ struct io_uring_task *tctx = req->task->io_uring;
+ struct io_ring_ctx *ctx = req->ctx;
+
+ io_dismantle_req(req);
+
+ percpu_counter_dec(&tctx->inflight);
+ if (atomic_read(&tctx->in_idle))
+ wake_up(&tctx->wait);
+ put_task_struct(req->task);
+
+ if (likely(!io_is_fallback_req(req)))
+ kmem_cache_free(req_cachep, req);
+ else
+ clear_bit_unlock(0, (unsigned long *) &ctx->fallback_req);
+ percpu_ref_put(&ctx->refs);
}
-static void io_req_link_next(struct io_kiocb *req)
+static void io_kill_linked_timeout(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_kiocb *link;
+ bool cancelled = false;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+ link = list_first_entry_or_null(&req->link_list, struct io_kiocb,
+ link_list);
+ /*
+ * Can happen if a linked timeout fired and link had been like
+ * req -> link t-out -> link t-out [-> ...]
+ */
+ if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) {
+ struct io_timeout_data *io = link->async_data;
+ int ret;
+
+ list_del_init(&link->link_list);
+ ret = hrtimer_try_to_cancel(&io->timer);
+ if (ret != -1) {
+ io_cqring_fill_event(link, -ECANCELED);
+ io_commit_cqring(ctx);
+ cancelled = true;
+ }
+ }
+ req->flags &= ~REQ_F_LINK_TIMEOUT;
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+
+ if (cancelled) {
+ io_cqring_ev_posted(ctx);
+ io_put_req(link);
+ }
+}
+
+static struct io_kiocb *io_req_link_next(struct io_kiocb *req)
{
struct io_kiocb *nxt;
@@ -710,66 +1971,331 @@
* potentially happen if the chain is messed up, check to be on the
* safe side.
*/
- nxt = list_first_entry_or_null(&req->link_list, struct io_kiocb, list);
- if (nxt) {
- list_del(&nxt->list);
- if (!list_empty(&req->link_list)) {
- INIT_LIST_HEAD(&nxt->link_list);
- list_splice(&req->link_list, &nxt->link_list);
- nxt->flags |= REQ_F_LINK;
- }
+ if (unlikely(list_empty(&req->link_list)))
+ return NULL;
- nxt->flags |= REQ_F_LINK_DONE;
- INIT_WORK(&nxt->work, io_sq_wq_submit_work);
- io_queue_async_work(req->ctx, nxt);
- }
+ nxt = list_first_entry(&req->link_list, struct io_kiocb, link_list);
+ list_del_init(&req->link_list);
+ if (!list_empty(&nxt->link_list))
+ nxt->flags |= REQ_F_LINK_HEAD;
+ return nxt;
}
/*
- * Called if REQ_F_LINK is set, and we fail the head request
+ * Called if REQ_F_LINK_HEAD is set, and we fail the head request
*/
static void io_fail_links(struct io_kiocb *req)
{
- struct io_kiocb *link;
+ struct io_ring_ctx *ctx = req->ctx;
+ unsigned long flags;
+ spin_lock_irqsave(&ctx->completion_lock, flags);
while (!list_empty(&req->link_list)) {
- link = list_first_entry(&req->link_list, struct io_kiocb, list);
- list_del(&link->list);
+ struct io_kiocb *link = list_first_entry(&req->link_list,
+ struct io_kiocb, link_list);
- io_cqring_add_event(req->ctx, link->user_data, -ECANCELED);
- __io_free_req(link);
+ list_del_init(&link->link_list);
+ trace_io_uring_fail_link(req, link);
+
+ io_cqring_fill_event(link, -ECANCELED);
+
+ /*
+ * It's ok to free under spinlock as they're not linked anymore,
+ * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
+ * work.fs->lock.
+ */
+ if (link->flags & REQ_F_WORK_INITIALIZED)
+ io_put_req_deferred(link, 2);
+ else
+ io_double_put_req(link);
}
+
+ io_commit_cqring(ctx);
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+
+ io_cqring_ev_posted(ctx);
}
-static void io_free_req(struct io_kiocb *req)
+static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
{
+ req->flags &= ~REQ_F_LINK_HEAD;
+ if (req->flags & REQ_F_LINK_TIMEOUT)
+ io_kill_linked_timeout(req);
+
/*
* If LINK is set, we have dependent requests in this chain. If we
* didn't fail this request, queue the first one up, moving any other
* dependencies to the next request. In case of failure, fail the rest
* of the chain.
*/
- if (req->flags & REQ_F_LINK) {
- if (req->flags & REQ_F_FAIL_LINK)
- io_fail_links(req);
- else
- io_req_link_next(req);
- }
+ if (likely(!(req->flags & REQ_F_FAIL_LINK)))
+ return io_req_link_next(req);
+ io_fail_links(req);
+ return NULL;
+}
+static struct io_kiocb *io_req_find_next(struct io_kiocb *req)
+{
+ if (likely(!(req->flags & REQ_F_LINK_HEAD)))
+ return NULL;
+ return __io_req_find_next(req);
+}
+
+static int io_req_task_work_add(struct io_kiocb *req, bool twa_signal_ok)
+{
+ struct task_struct *tsk = req->task;
+ struct io_ring_ctx *ctx = req->ctx;
+ enum task_work_notify_mode notify;
+ int ret;
+
+ if (tsk->flags & PF_EXITING)
+ return -ESRCH;
+
+ /*
+ * SQPOLL kernel thread doesn't need notification, just a wakeup. For
+ * all other cases, use TWA_SIGNAL unconditionally to ensure we're
+ * processing task_work. There's no reliable way to tell if TWA_RESUME
+ * will do the job.
+ */
+ notify = TWA_NONE;
+ if (!(ctx->flags & IORING_SETUP_SQPOLL) && twa_signal_ok)
+ notify = TWA_SIGNAL;
+
+ ret = task_work_add(tsk, &req->task_work, notify);
+ if (!ret)
+ wake_up_process(tsk);
+
+ return ret;
+}
+
+static void __io_req_task_cancel(struct io_kiocb *req, int error)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+
+ spin_lock_irq(&ctx->completion_lock);
+ io_cqring_fill_event(req, error);
+ io_commit_cqring(ctx);
+ spin_unlock_irq(&ctx->completion_lock);
+
+ io_cqring_ev_posted(ctx);
+ req_set_fail_links(req);
+ io_double_put_req(req);
+}
+
+static void io_req_task_cancel(struct callback_head *cb)
+{
+ struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
+ struct io_ring_ctx *ctx = req->ctx;
+
+ mutex_lock(&ctx->uring_lock);
+ __io_req_task_cancel(req, -ECANCELED);
+ mutex_unlock(&ctx->uring_lock);
+ percpu_ref_put(&ctx->refs);
+}
+
+static void __io_req_task_submit(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+
+ mutex_lock(&ctx->uring_lock);
+ if (!ctx->sqo_dead && !__io_sq_thread_acquire_mm(ctx))
+ __io_queue_sqe(req, NULL);
+ else
+ __io_req_task_cancel(req, -EFAULT);
+ mutex_unlock(&ctx->uring_lock);
+
+ if (ctx->flags & IORING_SETUP_SQPOLL)
+ io_sq_thread_drop_mm();
+}
+
+static void io_req_task_submit(struct callback_head *cb)
+{
+ struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
+ struct io_ring_ctx *ctx = req->ctx;
+
+ __io_req_task_submit(req);
+ percpu_ref_put(&ctx->refs);
+}
+
+static void io_req_task_queue(struct io_kiocb *req)
+{
+ int ret;
+
+ init_task_work(&req->task_work, io_req_task_submit);
+ percpu_ref_get(&req->ctx->refs);
+
+ ret = io_req_task_work_add(req, true);
+ if (unlikely(ret)) {
+ struct task_struct *tsk;
+
+ init_task_work(&req->task_work, io_req_task_cancel);
+ tsk = io_wq_get_task(req->ctx->io_wq);
+ task_work_add(tsk, &req->task_work, TWA_NONE);
+ wake_up_process(tsk);
+ }
+}
+
+static void io_queue_next(struct io_kiocb *req)
+{
+ struct io_kiocb *nxt = io_req_find_next(req);
+
+ if (nxt)
+ io_req_task_queue(nxt);
+}
+
+static void io_free_req(struct io_kiocb *req)
+{
+ io_queue_next(req);
__io_free_req(req);
}
+struct req_batch {
+ void *reqs[IO_IOPOLL_BATCH];
+ int to_free;
+
+ struct task_struct *task;
+ int task_refs;
+};
+
+static inline void io_init_req_batch(struct req_batch *rb)
+{
+ rb->to_free = 0;
+ rb->task_refs = 0;
+ rb->task = NULL;
+}
+
+static void __io_req_free_batch_flush(struct io_ring_ctx *ctx,
+ struct req_batch *rb)
+{
+ kmem_cache_free_bulk(req_cachep, rb->to_free, rb->reqs);
+ percpu_ref_put_many(&ctx->refs, rb->to_free);
+ rb->to_free = 0;
+}
+
+static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
+ struct req_batch *rb)
+{
+ if (rb->to_free)
+ __io_req_free_batch_flush(ctx, rb);
+ if (rb->task) {
+ struct io_uring_task *tctx = rb->task->io_uring;
+
+ percpu_counter_sub(&tctx->inflight, rb->task_refs);
+ if (atomic_read(&tctx->in_idle))
+ wake_up(&tctx->wait);
+ put_task_struct_many(rb->task, rb->task_refs);
+ rb->task = NULL;
+ }
+}
+
+static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req)
+{
+ if (unlikely(io_is_fallback_req(req))) {
+ io_free_req(req);
+ return;
+ }
+ if (req->flags & REQ_F_LINK_HEAD)
+ io_queue_next(req);
+
+ if (req->task != rb->task) {
+ if (rb->task) {
+ struct io_uring_task *tctx = rb->task->io_uring;
+
+ percpu_counter_sub(&tctx->inflight, rb->task_refs);
+ if (atomic_read(&tctx->in_idle))
+ wake_up(&tctx->wait);
+ put_task_struct_many(rb->task, rb->task_refs);
+ }
+ rb->task = req->task;
+ rb->task_refs = 0;
+ }
+ rb->task_refs++;
+
+ io_dismantle_req(req);
+ rb->reqs[rb->to_free++] = req;
+ if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs)))
+ __io_req_free_batch_flush(req->ctx, rb);
+}
+
+/*
+ * Drop reference to request, return next in chain (if there is one) if this
+ * was the last reference to this request.
+ */
+static struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
+{
+ struct io_kiocb *nxt = NULL;
+
+ if (refcount_dec_and_test(&req->refs)) {
+ nxt = io_req_find_next(req);
+ __io_free_req(req);
+ }
+ return nxt;
+}
+
static void io_put_req(struct io_kiocb *req)
{
if (refcount_dec_and_test(&req->refs))
io_free_req(req);
}
-static unsigned io_cqring_events(struct io_rings *rings)
+static void io_put_req_deferred_cb(struct callback_head *cb)
{
+ struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
+
+ io_free_req(req);
+}
+
+static void io_free_req_deferred(struct io_kiocb *req)
+{
+ int ret;
+
+ init_task_work(&req->task_work, io_put_req_deferred_cb);
+ ret = io_req_task_work_add(req, true);
+ if (unlikely(ret)) {
+ struct task_struct *tsk;
+
+ tsk = io_wq_get_task(req->ctx->io_wq);
+ task_work_add(tsk, &req->task_work, TWA_NONE);
+ wake_up_process(tsk);
+ }
+}
+
+static inline void io_put_req_deferred(struct io_kiocb *req, int refs)
+{
+ if (refcount_sub_and_test(refs, &req->refs))
+ io_free_req_deferred(req);
+}
+
+static struct io_wq_work *io_steal_work(struct io_kiocb *req)
+{
+ struct io_kiocb *nxt;
+
+ /*
+ * A ref is owned by io-wq in which context we're. So, if that's the
+ * last one, it's safe to steal next work. False negatives are Ok,
+ * it just will be re-punted async in io_put_work()
+ */
+ if (refcount_read(&req->refs) != 1)
+ return NULL;
+
+ nxt = io_req_find_next(req);
+ return nxt ? &nxt->work : NULL;
+}
+
+static void io_double_put_req(struct io_kiocb *req)
+{
+ /* drop both submit and complete references */
+ if (refcount_sub_and_test(2, &req->refs))
+ io_free_req(req);
+}
+
+static unsigned io_cqring_events(struct io_ring_ctx *ctx)
+{
+ struct io_rings *rings = ctx->rings;
+
/* See comment at the top of this file */
smp_rmb();
- return READ_ONCE(rings->cq.tail) - READ_ONCE(rings->cq.head);
+ return ctx->cached_cq_tail - READ_ONCE(rings->cq.head);
}
static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
@@ -780,43 +2306,96 @@
return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
}
+static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
+{
+ unsigned int cflags;
+
+ cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
+ cflags |= IORING_CQE_F_BUFFER;
+ req->flags &= ~REQ_F_BUFFER_SELECTED;
+ kfree(kbuf);
+ return cflags;
+}
+
+static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
+{
+ struct io_buffer *kbuf;
+
+ kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
+ return io_put_kbuf(req, kbuf);
+}
+
+static inline bool io_run_task_work(void)
+{
+ /*
+ * Not safe to run on exiting task, and the task_work handling will
+ * not add work to such a task.
+ */
+ if (unlikely(current->flags & PF_EXITING))
+ return false;
+ if (current->task_works) {
+ __set_current_state(TASK_RUNNING);
+ task_work_run();
+ return true;
+ }
+
+ return false;
+}
+
+static void io_iopoll_queue(struct list_head *again)
+{
+ struct io_kiocb *req;
+
+ do {
+ req = list_first_entry(again, struct io_kiocb, inflight_entry);
+ list_del(&req->inflight_entry);
+ __io_complete_rw(req, -EAGAIN, 0, NULL);
+ } while (!list_empty(again));
+}
+
/*
* Find and free completed poll iocbs
*/
static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
struct list_head *done)
{
- void *reqs[IO_IOPOLL_BATCH];
+ struct req_batch rb;
struct io_kiocb *req;
- int to_free;
+ LIST_HEAD(again);
- to_free = 0;
+ /* order with ->result store in io_complete_rw_iopoll() */
+ smp_rmb();
+
+ io_init_req_batch(&rb);
while (!list_empty(done)) {
- req = list_first_entry(done, struct io_kiocb, list);
- list_del(&req->list);
+ int cflags = 0;
- io_cqring_fill_event(ctx, req->user_data, req->result);
+ req = list_first_entry(done, struct io_kiocb, inflight_entry);
+ if (READ_ONCE(req->result) == -EAGAIN) {
+ req->result = 0;
+ req->iopoll_completed = 0;
+ list_move_tail(&req->inflight_entry, &again);
+ continue;
+ }
+ list_del(&req->inflight_entry);
+
+ if (req->flags & REQ_F_BUFFER_SELECTED)
+ cflags = io_put_rw_kbuf(req);
+
+ __io_cqring_fill_event(req, req->result, cflags);
(*nr_events)++;
- if (refcount_dec_and_test(&req->refs)) {
- /* If we're not using fixed files, we have to pair the
- * completion part with the file put. Use regular
- * completions for those, only batch free for fixed
- * file and non-linked commands.
- */
- if ((req->flags & (REQ_F_FIXED_FILE|REQ_F_LINK)) ==
- REQ_F_FIXED_FILE) {
- reqs[to_free++] = req;
- if (to_free == ARRAY_SIZE(reqs))
- io_free_req_many(ctx, reqs, &to_free);
- } else {
- io_free_req(req);
- }
- }
+ if (refcount_dec_and_test(&req->refs))
+ io_req_free_batch(&rb, req);
}
io_commit_cqring(ctx);
- io_free_req_many(ctx, reqs, &to_free);
+ if (ctx->flags & IORING_SETUP_SQPOLL)
+ io_cqring_ev_posted(ctx);
+ io_req_free_batch_finish(ctx, &rb);
+
+ if (!list_empty(&again))
+ io_iopoll_queue(&again);
}
static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
@@ -834,16 +2413,16 @@
spin = !ctx->poll_multi_file && *nr_events < min;
ret = 0;
- list_for_each_entry_safe(req, tmp, &ctx->poll_list, list) {
- struct kiocb *kiocb = &req->rw;
+ list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
+ struct kiocb *kiocb = &req->rw.kiocb;
/*
- * Move completed entries to our local list. If we find a
- * request that requires polling, break out and complete
- * the done list first, if we have entries there.
+ * Move completed and retryable entries to our local lists.
+ * If we find a request that requires polling, break out
+ * and complete those lists first, if we have entries there.
*/
- if (req->flags & REQ_F_IOPOLL_COMPLETED) {
- list_move_tail(&req->list, &done);
+ if (READ_ONCE(req->iopoll_completed)) {
+ list_move_tail(&req->inflight_entry, &done);
continue;
}
if (!list_empty(&done))
@@ -853,6 +2432,10 @@
if (ret < 0)
break;
+ /* iopoll may have completed current req */
+ if (READ_ONCE(req->iopoll_completed))
+ list_move_tail(&req->inflight_entry, &done);
+
if (ret && spin)
spin = false;
ret = 0;
@@ -865,20 +2448,20 @@
}
/*
- * Poll for a mininum of 'min' events. Note that if min == 0 we consider that a
+ * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
* non-spinning poll check - we'll still enter the driver poll loop, but only
* as a non-spinning completion check.
*/
static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events,
long min)
{
- while (!list_empty(&ctx->poll_list) && !need_resched()) {
+ while (!list_empty(&ctx->iopoll_list) && !need_resched()) {
int ret;
ret = io_do_iopoll(ctx, nr_events, min);
if (ret < 0)
return ret;
- if (!min || *nr_events >= min)
+ if (*nr_events >= min)
return 0;
}
@@ -889,29 +2472,37 @@
* We can't just wait for polled events to come to us, we have to actively
* find and complete them.
*/
-static void io_iopoll_reap_events(struct io_ring_ctx *ctx)
+static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
{
if (!(ctx->flags & IORING_SETUP_IOPOLL))
return;
mutex_lock(&ctx->uring_lock);
- while (!list_empty(&ctx->poll_list)) {
+ while (!list_empty(&ctx->iopoll_list)) {
unsigned int nr_events = 0;
- io_iopoll_getevents(ctx, &nr_events, 1);
+ io_do_iopoll(ctx, &nr_events, 0);
+ /* let it sleep and repeat later if can't complete a request */
+ if (nr_events == 0)
+ break;
/*
* Ensure we allow local-to-the-cpu processing to take place,
* in this case we need to ensure that we reap all events.
+ * Also let task_work, etc. to progress by releasing the mutex
*/
- cond_resched();
+ if (need_resched()) {
+ mutex_unlock(&ctx->uring_lock);
+ cond_resched();
+ mutex_lock(&ctx->uring_lock);
+ }
}
mutex_unlock(&ctx->uring_lock);
}
-static int io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events,
- long min)
+static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
{
+ unsigned int nr_events = 0;
int iters = 0, ret = 0;
/*
@@ -921,14 +2512,14 @@
*/
mutex_lock(&ctx->uring_lock);
do {
- int tmin = 0;
-
/*
* Don't enter poll loop if we already have events pending.
* If we do, we can potentially be spinning for commands that
* already triggered a CQE (eg in error).
*/
- if (io_cqring_events(ctx->rings))
+ if (test_bit(0, &ctx->cq_check_overflow))
+ __io_cqring_overflow_flush(ctx, false, NULL, NULL);
+ if (io_cqring_events(ctx))
break;
/*
@@ -943,17 +2534,15 @@
*/
if (!(++iters & 7)) {
mutex_unlock(&ctx->uring_lock);
+ io_run_task_work();
mutex_lock(&ctx->uring_lock);
}
- if (*nr_events < min)
- tmin = min - *nr_events;
-
- ret = io_iopoll_getevents(ctx, nr_events, tmin);
+ ret = io_iopoll_getevents(ctx, &nr_events, min);
if (ret <= 0)
break;
ret = 0;
- } while (min && !*nr_events && !need_resched());
+ } while (min && !nr_events && !need_resched());
mutex_unlock(&ctx->uring_lock);
return ret;
@@ -973,31 +2562,127 @@
file_end_write(req->file);
}
-static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
+static void io_complete_rw_common(struct kiocb *kiocb, long res,
+ struct io_comp_state *cs)
{
- struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+ struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+ int cflags = 0;
if (kiocb->ki_flags & IOCB_WRITE)
kiocb_end_write(req);
- if ((req->flags & REQ_F_LINK) && res != req->result)
- req->flags |= REQ_F_FAIL_LINK;
- io_cqring_add_event(req->ctx, req->user_data, res);
- io_put_req(req);
+ if (res != req->result)
+ req_set_fail_links(req);
+ if (req->flags & REQ_F_BUFFER_SELECTED)
+ cflags = io_put_rw_kbuf(req);
+ __io_req_complete(req, res, cflags, cs);
+}
+
+#ifdef CONFIG_BLOCK
+static bool io_resubmit_prep(struct io_kiocb *req, int error)
+{
+ struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
+ ssize_t ret = -ECANCELED;
+ struct iov_iter iter;
+ int rw;
+
+ if (error) {
+ ret = error;
+ goto end_req;
+ }
+
+ switch (req->opcode) {
+ case IORING_OP_READV:
+ case IORING_OP_READ_FIXED:
+ case IORING_OP_READ:
+ rw = READ;
+ break;
+ case IORING_OP_WRITEV:
+ case IORING_OP_WRITE_FIXED:
+ case IORING_OP_WRITE:
+ rw = WRITE;
+ break;
+ default:
+ printk_once(KERN_WARNING "io_uring: bad opcode in resubmit %d\n",
+ req->opcode);
+ goto end_req;
+ }
+
+ if (!req->async_data) {
+ ret = io_import_iovec(rw, req, &iovec, &iter, false);
+ if (ret < 0)
+ goto end_req;
+ ret = io_setup_async_rw(req, iovec, inline_vecs, &iter, false);
+ if (!ret)
+ return true;
+ kfree(iovec);
+ } else {
+ return true;
+ }
+end_req:
+ req_set_fail_links(req);
+ return false;
+}
+#endif
+
+static bool io_rw_reissue(struct io_kiocb *req, long res)
+{
+#ifdef CONFIG_BLOCK
+ umode_t mode = file_inode(req->file)->i_mode;
+ int ret;
+
+ if (!S_ISBLK(mode) && !S_ISREG(mode))
+ return false;
+ if ((res != -EAGAIN && res != -EOPNOTSUPP) || io_wq_current_is_worker())
+ return false;
+ /*
+ * If ref is dying, we might be running poll reap from the exit work.
+ * Don't attempt to reissue from that path, just let it fail with
+ * -EAGAIN.
+ */
+ if (percpu_ref_is_dying(&req->ctx->refs))
+ return false;
+
+ ret = io_sq_thread_acquire_mm(req->ctx, req);
+
+ if (io_resubmit_prep(req, ret)) {
+ refcount_inc(&req->refs);
+ io_queue_async_work(req);
+ return true;
+ }
+
+#endif
+ return false;
+}
+
+static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
+ struct io_comp_state *cs)
+{
+ if (!io_rw_reissue(req, res))
+ io_complete_rw_common(&req->rw.kiocb, res, cs);
+}
+
+static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
+{
+ struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+
+ __io_complete_rw(req, res, res2, NULL);
}
static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
{
- struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+ struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
if (kiocb->ki_flags & IOCB_WRITE)
kiocb_end_write(req);
- if ((req->flags & REQ_F_LINK) && res != req->result)
- req->flags |= REQ_F_FAIL_LINK;
- req->result = res;
- if (res != -EAGAIN)
- req->flags |= REQ_F_IOPOLL_COMPLETED;
+ if (res != -EAGAIN && res != req->result)
+ req_set_fail_links(req);
+
+ WRITE_ONCE(req->result, res);
+ /* order with io_poll_complete() checking ->result */
+ smp_wmb();
+ WRITE_ONCE(req->iopoll_completed, 1);
}
/*
@@ -1015,14 +2700,14 @@
* how we do polling eventually, not spinning if we're on potentially
* different devices.
*/
- if (list_empty(&ctx->poll_list)) {
+ if (list_empty(&ctx->iopoll_list)) {
ctx->poll_multi_file = false;
} else if (!ctx->poll_multi_file) {
struct io_kiocb *list_req;
- list_req = list_first_entry(&ctx->poll_list, struct io_kiocb,
- list);
- if (list_req->rw.ki_filp != req->rw.ki_filp)
+ list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
+ inflight_entry);
+ if (list_req->file != req->file)
ctx->poll_multi_file = true;
}
@@ -1030,21 +2715,27 @@
* For fast devices, IO may have already completed. If it has, add
* it to the front so we find it first.
*/
- if (req->flags & REQ_F_IOPOLL_COMPLETED)
- list_add(&req->list, &ctx->poll_list);
+ if (READ_ONCE(req->iopoll_completed))
+ list_add(&req->inflight_entry, &ctx->iopoll_list);
else
- list_add_tail(&req->list, &ctx->poll_list);
+ list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
+
+ if ((ctx->flags & IORING_SETUP_SQPOLL) &&
+ wq_has_sleeper(&ctx->sq_data->wait))
+ wake_up(&ctx->sq_data->wait);
}
-static void io_file_put(struct io_submit_state *state)
+static void __io_state_file_put(struct io_submit_state *state)
{
- if (state->file) {
- int diff = state->has_refs - state->used_refs;
+ if (state->has_refs)
+ fput_many(state->file, state->has_refs);
+ state->file = NULL;
+}
- if (diff)
- fput_many(state->file, diff);
- state->file = NULL;
- }
+static inline void io_state_file_put(struct io_submit_state *state)
+{
+ if (state->file)
+ __io_state_file_put(state);
}
/*
@@ -1052,77 +2743,92 @@
* assuming most submissions are for one file, or at least that each file
* has more than one submission.
*/
-static struct file *io_file_get(struct io_submit_state *state, int fd)
+static struct file *__io_file_get(struct io_submit_state *state, int fd)
{
if (!state)
return fget(fd);
if (state->file) {
if (state->fd == fd) {
- state->used_refs++;
- state->ios_left--;
+ state->has_refs--;
return state->file;
}
- io_file_put(state);
+ __io_state_file_put(state);
}
state->file = fget_many(fd, state->ios_left);
if (!state->file)
return NULL;
state->fd = fd;
- state->has_refs = state->ios_left;
- state->used_refs = 1;
- state->ios_left--;
+ state->has_refs = state->ios_left - 1;
return state->file;
}
+static bool io_bdev_nowait(struct block_device *bdev)
+{
+#ifdef CONFIG_BLOCK
+ return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
+#else
+ return true;
+#endif
+}
+
/*
* If we tracked the file through the SCM inflight mechanism, we could support
* any file. For now, just ensure that anything potentially problematic is done
* inline.
*/
-static bool io_file_supports_async(struct file *file)
+static bool io_file_supports_async(struct file *file, int rw)
{
umode_t mode = file_inode(file)->i_mode;
- if (S_ISBLK(mode) || S_ISCHR(mode))
+ if (S_ISBLK(mode)) {
+ if (io_bdev_nowait(file->f_inode->i_bdev))
+ return true;
+ return false;
+ }
+ if (S_ISSOCK(mode))
return true;
- if (S_ISREG(mode) && file->f_op != &io_uring_fops)
+ if (S_ISREG(mode)) {
+ if (io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
+ file->f_op != &io_uring_fops)
+ return true;
+ return false;
+ }
+
+ /* any ->read/write should understand O_NONBLOCK */
+ if (file->f_flags & O_NONBLOCK)
return true;
- return false;
+ if (!(file->f_mode & FMODE_NOWAIT))
+ return false;
+
+ if (rw == READ)
+ return file->f_op->read_iter != NULL;
+
+ return file->f_op->write_iter != NULL;
}
-static int io_prep_rw(struct io_kiocb *req, const struct sqe_submit *s,
- bool force_nonblock)
+static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
- const struct io_uring_sqe *sqe = s->sqe;
struct io_ring_ctx *ctx = req->ctx;
- struct kiocb *kiocb = &req->rw;
+ struct kiocb *kiocb = &req->rw.kiocb;
unsigned ioprio;
int ret;
- if (!req->file)
- return -EBADF;
-
if (S_ISREG(file_inode(req->file)->i_mode))
req->flags |= REQ_F_ISREG;
- if (force_nonblock)
- req->fsize = rlimit(RLIMIT_FSIZE);
-
- /*
- * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
- * we know to async punt it even if it was opened O_NONBLOCK
- */
- if (force_nonblock && !io_file_supports_async(req->file)) {
- req->flags |= REQ_F_MUST_PUNT;
- return -EAGAIN;
- }
-
kiocb->ki_pos = READ_ONCE(sqe->off);
- kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
+ if (kiocb->ki_pos == -1 && !(req->file->f_mode & FMODE_STREAM)) {
+ req->flags |= REQ_F_CUR_POS;
+ kiocb->ki_pos = req->file->f_pos;
+ }
kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
+ kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
+ ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
+ if (unlikely(ret))
+ return ret;
ioprio = READ_ONCE(sqe->ioprio);
if (ioprio) {
@@ -1134,18 +2840,10 @@
} else
kiocb->ki_ioprio = get_current_ioprio();
- ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
- if (unlikely(ret))
- return ret;
-
/* don't allow async punt if RWF_NOWAIT was requested */
- if ((kiocb->ki_flags & IOCB_NOWAIT) ||
- (req->file->f_flags & O_NONBLOCK))
+ if (kiocb->ki_flags & IOCB_NOWAIT)
req->flags |= REQ_F_NOWAIT;
- if (force_nonblock)
- kiocb->ki_flags |= IOCB_NOWAIT;
-
if (ctx->flags & IORING_SETUP_IOPOLL) {
if (!(kiocb->ki_flags & IOCB_DIRECT) ||
!kiocb->ki_filp->f_op->iopoll)
@@ -1153,12 +2851,16 @@
kiocb->ki_flags |= IOCB_HIPRI;
kiocb->ki_complete = io_complete_rw_iopoll;
- req->result = 0;
+ req->iopoll_completed = 0;
} else {
if (kiocb->ki_flags & IOCB_HIPRI)
return -EINVAL;
kiocb->ki_complete = io_complete_rw;
}
+
+ req->rw.addr = READ_ONCE(sqe->addr);
+ req->rw.len = READ_ONCE(sqe->len);
+ req->buf_index = READ_ONCE(sqe->buf_index);
return 0;
}
@@ -1177,33 +2879,49 @@
* IO with EINTR.
*/
ret = -EINTR;
- /* fall through */
+ fallthrough;
default:
kiocb->ki_complete(kiocb, ret, 0);
}
}
-static int io_import_fixed(struct io_ring_ctx *ctx, int rw,
- const struct io_uring_sqe *sqe,
- struct iov_iter *iter)
+static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
+ struct io_comp_state *cs)
{
- size_t len = READ_ONCE(sqe->len);
+ struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+ struct io_async_rw *io = req->async_data;
+
+ /* add previously done IO, if any */
+ if (io && io->bytes_done > 0) {
+ if (ret < 0)
+ ret = io->bytes_done;
+ else
+ ret += io->bytes_done;
+ }
+
+ if (req->flags & REQ_F_CUR_POS)
+ req->file->f_pos = kiocb->ki_pos;
+ if (ret >= 0 && kiocb->ki_complete == io_complete_rw)
+ __io_complete_rw(req, ret, 0, cs);
+ else
+ io_rw_done(kiocb, ret);
+}
+
+static ssize_t io_import_fixed(struct io_kiocb *req, int rw,
+ struct iov_iter *iter)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ size_t len = req->rw.len;
struct io_mapped_ubuf *imu;
- unsigned index, buf_index;
+ u16 index, buf_index = req->buf_index;
size_t offset;
u64 buf_addr;
- /* attempt to use fixed buffers without having provided iovecs */
- if (unlikely(!ctx->user_bufs))
- return -EFAULT;
-
- buf_index = READ_ONCE(sqe->buf_index);
if (unlikely(buf_index >= ctx->nr_user_bufs))
return -EFAULT;
-
index = array_index_nospec(buf_index, ctx->nr_user_bufs);
imu = &ctx->user_bufs[index];
- buf_addr = READ_ONCE(sqe->addr);
+ buf_addr = req->rw.addr;
/* overflow */
if (buf_addr + len < buf_addr)
@@ -1257,101 +2975,215 @@
return len;
}
-static ssize_t io_import_iovec(struct io_ring_ctx *ctx, int rw,
- struct io_kiocb *req, struct iovec **iovec,
- struct iov_iter *iter)
+static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
{
- const struct io_uring_sqe *sqe = req->submit.sqe;
- void __user *buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
- size_t sqe_len = READ_ONCE(sqe->len);
+ if (needs_lock)
+ mutex_unlock(&ctx->uring_lock);
+}
+
+static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
+{
+ /*
+ * "Normal" inline submissions always hold the uring_lock, since we
+ * grab it from the system call. Same is true for the SQPOLL offload.
+ * The only exception is when we've detached the request and issue it
+ * from an async worker thread, grab the lock for that case.
+ */
+ if (needs_lock)
+ mutex_lock(&ctx->uring_lock);
+}
+
+static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
+ int bgid, struct io_buffer *kbuf,
+ bool needs_lock)
+{
+ struct io_buffer *head;
+
+ if (req->flags & REQ_F_BUFFER_SELECTED)
+ return kbuf;
+
+ io_ring_submit_lock(req->ctx, needs_lock);
+
+ lockdep_assert_held(&req->ctx->uring_lock);
+
+ head = xa_load(&req->ctx->io_buffers, bgid);
+ if (head) {
+ if (!list_empty(&head->list)) {
+ kbuf = list_last_entry(&head->list, struct io_buffer,
+ list);
+ list_del(&kbuf->list);
+ } else {
+ kbuf = head;
+ xa_erase(&req->ctx->io_buffers, bgid);
+ }
+ if (*len > kbuf->len)
+ *len = kbuf->len;
+ } else {
+ kbuf = ERR_PTR(-ENOBUFS);
+ }
+
+ io_ring_submit_unlock(req->ctx, needs_lock);
+
+ return kbuf;
+}
+
+static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
+ bool needs_lock)
+{
+ struct io_buffer *kbuf;
+ u16 bgid;
+
+ kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
+ bgid = req->buf_index;
+ kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
+ if (IS_ERR(kbuf))
+ return kbuf;
+ req->rw.addr = (u64) (unsigned long) kbuf;
+ req->flags |= REQ_F_BUFFER_SELECTED;
+ return u64_to_user_ptr(kbuf->addr);
+}
+
+#ifdef CONFIG_COMPAT
+static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
+ bool needs_lock)
+{
+ struct compat_iovec __user *uiov;
+ compat_ssize_t clen;
+ void __user *buf;
+ ssize_t len;
+
+ uiov = u64_to_user_ptr(req->rw.addr);
+ if (!access_ok(uiov, sizeof(*uiov)))
+ return -EFAULT;
+ if (__get_user(clen, &uiov->iov_len))
+ return -EFAULT;
+ if (clen < 0)
+ return -EINVAL;
+
+ len = clen;
+ buf = io_rw_buffer_select(req, &len, needs_lock);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+ iov[0].iov_base = buf;
+ iov[0].iov_len = (compat_size_t) len;
+ return 0;
+}
+#endif
+
+static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
+ bool needs_lock)
+{
+ struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
+ void __user *buf;
+ ssize_t len;
+
+ if (copy_from_user(iov, uiov, sizeof(*uiov)))
+ return -EFAULT;
+
+ len = iov[0].iov_len;
+ if (len < 0)
+ return -EINVAL;
+ buf = io_rw_buffer_select(req, &len, needs_lock);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+ iov[0].iov_base = buf;
+ iov[0].iov_len = len;
+ return 0;
+}
+
+static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
+ bool needs_lock)
+{
+ if (req->flags & REQ_F_BUFFER_SELECTED) {
+ struct io_buffer *kbuf;
+
+ kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
+ iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
+ iov[0].iov_len = kbuf->len;
+ return 0;
+ }
+ if (req->rw.len != 1)
+ return -EINVAL;
+
+#ifdef CONFIG_COMPAT
+ if (req->ctx->compat)
+ return io_compat_import(req, iov, needs_lock);
+#endif
+
+ return __io_iov_buffer_select(req, iov, needs_lock);
+}
+
+static ssize_t __io_import_iovec(int rw, struct io_kiocb *req,
+ struct iovec **iovec, struct iov_iter *iter,
+ bool needs_lock)
+{
+ void __user *buf = u64_to_user_ptr(req->rw.addr);
+ size_t sqe_len = req->rw.len;
+ ssize_t ret;
u8 opcode;
- opcode = req->submit.opcode;
- if (opcode == IORING_OP_READ_FIXED ||
- opcode == IORING_OP_WRITE_FIXED) {
- ssize_t ret = io_import_fixed(ctx, rw, sqe, iter);
+ opcode = req->opcode;
+ if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
+ *iovec = NULL;
+ return io_import_fixed(req, rw, iter);
+ }
+
+ /* buffer index only valid with fixed read/write, or buffer select */
+ if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
+ return -EINVAL;
+
+ if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+ req->rw.len = sqe_len;
+ }
+
+ ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
*iovec = NULL;
return ret;
}
- if (!req->submit.has_user)
- return -EFAULT;
-
-#ifdef CONFIG_COMPAT
- if (ctx->compat)
- return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV,
- iovec, iter);
-#endif
-
- return import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter);
-}
-
-static inline bool io_should_merge(struct async_list *al, struct kiocb *kiocb)
-{
- if (al->file == kiocb->ki_filp) {
- off_t start, end;
-
- /*
- * Allow merging if we're anywhere in the range of the same
- * page. Generally this happens for sub-page reads or writes,
- * and it's beneficial to allow the first worker to bring the
- * page in and the piggy backed work can then work on the
- * cached page.
- */
- start = al->io_start & PAGE_MASK;
- end = (al->io_start + al->io_len + PAGE_SIZE - 1) & PAGE_MASK;
- if (kiocb->ki_pos >= start && kiocb->ki_pos <= end)
- return true;
- }
-
- al->file = NULL;
- return false;
-}
-
-/*
- * Make a note of the last file/offset/direction we punted to async
- * context. We'll use this information to see if we can piggy back a
- * sequential request onto the previous one, if it's still hasn't been
- * completed by the async worker.
- */
-static void io_async_list_note(int rw, struct io_kiocb *req, size_t len)
-{
- struct async_list *async_list = &req->ctx->pending_async[rw];
- struct kiocb *kiocb = &req->rw;
- struct file *filp = kiocb->ki_filp;
-
- if (io_should_merge(async_list, kiocb)) {
- unsigned long max_bytes;
-
- /* Use 8x RA size as a decent limiter for both reads/writes */
- max_bytes = filp->f_ra.ra_pages << (PAGE_SHIFT + 3);
- if (!max_bytes)
- max_bytes = VM_READAHEAD_PAGES << (PAGE_SHIFT + 3);
-
- /* If max len are exceeded, reset the state */
- if (async_list->io_len + len <= max_bytes) {
- req->flags |= REQ_F_SEQ_PREV;
- async_list->io_len += len;
- } else {
- async_list->file = NULL;
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ ret = io_iov_buffer_select(req, *iovec, needs_lock);
+ if (!ret) {
+ ret = (*iovec)->iov_len;
+ iov_iter_init(iter, rw, *iovec, 1, ret);
}
+ *iovec = NULL;
+ return ret;
}
- /* New file? Reset state. */
- if (async_list->file != filp) {
- async_list->io_start = kiocb->ki_pos;
- async_list->io_len = len;
- async_list->file = filp;
- }
+ return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
+ req->ctx->compat);
+}
+
+static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
+ struct iovec **iovec, struct iov_iter *iter,
+ bool needs_lock)
+{
+ struct io_async_rw *iorw = req->async_data;
+
+ if (!iorw)
+ return __io_import_iovec(rw, req, iovec, iter, needs_lock);
+ *iovec = NULL;
+ return 0;
+}
+
+static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
+{
+ return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
}
/*
* For files that don't have ->read_iter() and ->write_iter(), handle them
* by looping over ->read() or ->write() manually.
*/
-static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb,
- struct iov_iter *iter)
+static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
{
+ struct kiocb *kiocb = &req->rw.kiocb;
+ struct file *file = req->file;
ssize_t ret = 0;
/*
@@ -1371,202 +3203,552 @@
if (!iov_iter_is_bvec(iter)) {
iovec = iov_iter_iovec(iter);
} else {
- /* fixed buffers import bvec */
- iovec.iov_base = kmap(iter->bvec->bv_page)
- + iter->iov_offset;
- iovec.iov_len = min(iter->count,
- iter->bvec->bv_len - iter->iov_offset);
+ iovec.iov_base = u64_to_user_ptr(req->rw.addr);
+ iovec.iov_len = req->rw.len;
}
if (rw == READ) {
nr = file->f_op->read(file, iovec.iov_base,
- iovec.iov_len, &kiocb->ki_pos);
+ iovec.iov_len, io_kiocb_ppos(kiocb));
} else {
nr = file->f_op->write(file, iovec.iov_base,
- iovec.iov_len, &kiocb->ki_pos);
+ iovec.iov_len, io_kiocb_ppos(kiocb));
}
- if (iov_iter_is_bvec(iter))
- kunmap(iter->bvec->bv_page);
-
if (nr < 0) {
if (!ret)
ret = nr;
break;
}
+ if (!iov_iter_is_bvec(iter)) {
+ iov_iter_advance(iter, nr);
+ } else {
+ req->rw.len -= nr;
+ req->rw.addr += nr;
+ }
ret += nr;
if (nr != iovec.iov_len)
break;
- iov_iter_advance(iter, nr);
}
return ret;
}
-static int io_read(struct io_kiocb *req, const struct sqe_submit *s,
- bool force_nonblock)
+static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
+ const struct iovec *fast_iov, struct iov_iter *iter)
{
- struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
- struct kiocb *kiocb = &req->rw;
- struct iov_iter iter;
- struct file *file;
- size_t iov_count;
- ssize_t read_size, ret;
+ struct io_async_rw *rw = req->async_data;
- ret = io_prep_rw(req, s, force_nonblock);
- if (ret)
- return ret;
- file = kiocb->ki_filp;
+ memcpy(&rw->iter, iter, sizeof(*iter));
+ rw->free_iovec = iovec;
+ rw->bytes_done = 0;
+ /* can only be fixed buffers, no need to do anything */
+ if (iov_iter_is_bvec(iter))
+ return;
+ if (!iovec) {
+ unsigned iov_off = 0;
- if (unlikely(!(file->f_mode & FMODE_READ)))
- return -EBADF;
-
- ret = io_import_iovec(req->ctx, READ, req, &iovec, &iter);
- if (ret < 0)
- return ret;
-
- read_size = ret;
- if (req->flags & REQ_F_LINK)
- req->result = read_size;
-
- iov_count = iov_iter_count(&iter);
- ret = rw_verify_area(READ, file, &kiocb->ki_pos, iov_count);
- if (!ret) {
- ssize_t ret2;
-
- if (file->f_op->read_iter)
- ret2 = call_read_iter(file, kiocb, &iter);
- else if (req->file->f_op->read)
- ret2 = loop_rw_iter(READ, file, kiocb, &iter);
- else
- ret2 = -EINVAL;
-
- /*
- * In case of a short read, punt to async. This can happen
- * if we have data partially cached. Alternatively we can
- * return the short read, in which case the application will
- * need to issue another SQE and wait for it. That SQE will
- * need async punt anyway, so it's more efficient to do it
- * here.
- */
- if (force_nonblock && !(req->flags & REQ_F_NOWAIT) &&
- (req->flags & REQ_F_ISREG) &&
- ret2 > 0 && ret2 < read_size)
- ret2 = -EAGAIN;
- /* Catch -EAGAIN return for forced non-blocking submission */
- if (!force_nonblock || ret2 != -EAGAIN) {
- io_rw_done(kiocb, ret2);
- } else {
- /*
- * If ->needs_lock is true, we're already in async
- * context.
- */
- if (!s->needs_lock)
- io_async_list_note(READ, req, iov_count);
- ret = -EAGAIN;
+ rw->iter.iov = rw->fast_iov;
+ if (iter->iov != fast_iov) {
+ iov_off = iter->iov - fast_iov;
+ rw->iter.iov += iov_off;
}
+ if (rw->fast_iov != fast_iov)
+ memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
+ sizeof(struct iovec) * iter->nr_segs);
+ } else {
+ req->flags |= REQ_F_NEED_CLEANUP;
}
- kfree(iovec);
- return ret;
}
-static int io_write(struct io_kiocb *req, const struct sqe_submit *s,
- bool force_nonblock)
+static inline int __io_alloc_async_data(struct io_kiocb *req)
{
- struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
- struct kiocb *kiocb = &req->rw;
- struct iov_iter iter;
- struct file *file;
- size_t iov_count;
+ WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
+ req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
+ return req->async_data == NULL;
+}
+
+static int io_alloc_async_data(struct io_kiocb *req)
+{
+ if (!io_op_defs[req->opcode].needs_async_data)
+ return 0;
+
+ return __io_alloc_async_data(req);
+}
+
+static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
+ const struct iovec *fast_iov,
+ struct iov_iter *iter, bool force)
+{
+ if (!force && !io_op_defs[req->opcode].needs_async_data)
+ return 0;
+ if (!req->async_data) {
+ if (__io_alloc_async_data(req))
+ return -ENOMEM;
+
+ io_req_map_rw(req, iovec, fast_iov, iter);
+ }
+ return 0;
+}
+
+static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
+{
+ struct io_async_rw *iorw = req->async_data;
+ struct iovec *iov = iorw->fast_iov;
ssize_t ret;
- ret = io_prep_rw(req, s, force_nonblock);
+ ret = __io_import_iovec(rw, req, &iov, &iorw->iter, false);
+ if (unlikely(ret < 0))
+ return ret;
+
+ iorw->bytes_done = 0;
+ iorw->free_iovec = iov;
+ if (iov)
+ req->flags |= REQ_F_NEED_CLEANUP;
+ return 0;
+}
+
+static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ ssize_t ret;
+
+ ret = io_prep_rw(req, sqe);
if (ret)
return ret;
- file = kiocb->ki_filp;
- if (unlikely(!(file->f_mode & FMODE_WRITE)))
+ if (unlikely(!(req->file->f_mode & FMODE_READ)))
return -EBADF;
- ret = io_import_iovec(req->ctx, WRITE, req, &iovec, &iter);
+ /* either don't need iovec imported or already have it */
+ if (!req->async_data)
+ return 0;
+ return io_rw_prep_async(req, READ);
+}
+
+/*
+ * This is our waitqueue callback handler, registered through lock_page_async()
+ * when we initially tried to do the IO with the iocb armed our waitqueue.
+ * This gets called when the page is unlocked, and we generally expect that to
+ * happen when the page IO is completed and the page is now uptodate. This will
+ * queue a task_work based retry of the operation, attempting to copy the data
+ * again. If the latter fails because the page was NOT uptodate, then we will
+ * do a thread based blocking retry of the operation. That's the unexpected
+ * slow path.
+ */
+static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
+ int sync, void *arg)
+{
+ struct wait_page_queue *wpq;
+ struct io_kiocb *req = wait->private;
+ struct wait_page_key *key = arg;
+ int ret;
+
+ wpq = container_of(wait, struct wait_page_queue, wait);
+
+ if (!wake_page_match(wpq, key))
+ return 0;
+
+ req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
+ list_del_init(&wait->entry);
+
+ init_task_work(&req->task_work, io_req_task_submit);
+ percpu_ref_get(&req->ctx->refs);
+
+ /* submit ref gets dropped, acquire a new one */
+ refcount_inc(&req->refs);
+ ret = io_req_task_work_add(req, true);
+ if (unlikely(ret)) {
+ struct task_struct *tsk;
+
+ /* queue just for cancelation */
+ init_task_work(&req->task_work, io_req_task_cancel);
+ tsk = io_wq_get_task(req->ctx->io_wq);
+ task_work_add(tsk, &req->task_work, TWA_NONE);
+ wake_up_process(tsk);
+ }
+ return 1;
+}
+
+/*
+ * This controls whether a given IO request should be armed for async page
+ * based retry. If we return false here, the request is handed to the async
+ * worker threads for retry. If we're doing buffered reads on a regular file,
+ * we prepare a private wait_page_queue entry and retry the operation. This
+ * will either succeed because the page is now uptodate and unlocked, or it
+ * will register a callback when the page is unlocked at IO completion. Through
+ * that callback, io_uring uses task_work to setup a retry of the operation.
+ * That retry will attempt the buffered read again. The retry will generally
+ * succeed, or in rare cases where it fails, we then fall back to using the
+ * async worker threads for a blocking retry.
+ */
+static bool io_rw_should_retry(struct io_kiocb *req)
+{
+ struct io_async_rw *rw = req->async_data;
+ struct wait_page_queue *wait = &rw->wpq;
+ struct kiocb *kiocb = &req->rw.kiocb;
+
+ /* never retry for NOWAIT, we just complete with -EAGAIN */
+ if (req->flags & REQ_F_NOWAIT)
+ return false;
+
+ /* Only for buffered IO */
+ if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
+ return false;
+
+ /*
+ * just use poll if we can, and don't attempt if the fs doesn't
+ * support callback based unlocks
+ */
+ if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
+ return false;
+
+ wait->wait.func = io_async_buf_func;
+ wait->wait.private = req;
+ wait->wait.flags = 0;
+ INIT_LIST_HEAD(&wait->wait.entry);
+ kiocb->ki_flags |= IOCB_WAITQ;
+ kiocb->ki_flags &= ~IOCB_NOWAIT;
+ kiocb->ki_waitq = wait;
+ return true;
+}
+
+static int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
+{
+ if (req->file->f_op->read_iter)
+ return call_read_iter(req->file, &req->rw.kiocb, iter);
+ else if (req->file->f_op->read)
+ return loop_rw_iter(READ, req, iter);
+ else
+ return -EINVAL;
+}
+
+static int io_read(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
+ struct kiocb *kiocb = &req->rw.kiocb;
+ struct iov_iter __iter, *iter = &__iter;
+ struct io_async_rw *rw = req->async_data;
+ ssize_t io_size, ret, ret2;
+ bool no_async;
+
+ if (rw)
+ iter = &rw->iter;
+
+ ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
if (ret < 0)
return ret;
+ io_size = iov_iter_count(iter);
+ req->result = io_size;
+ ret = 0;
- if (req->flags & REQ_F_LINK)
- req->result = ret;
+ /* Ensure we clear previously set non-block flag */
+ if (!force_nonblock)
+ kiocb->ki_flags &= ~IOCB_NOWAIT;
+ else
+ kiocb->ki_flags |= IOCB_NOWAIT;
- iov_count = iov_iter_count(&iter);
- ret = -EAGAIN;
- if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT)) {
- /* If ->needs_lock is true, we're already in async context. */
- if (!s->needs_lock)
- io_async_list_note(WRITE, req, iov_count);
+ /* If the file doesn't support async, just async punt */
+ no_async = force_nonblock && !io_file_supports_async(req->file, READ);
+ if (no_async)
+ goto copy_iov;
+
+ ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size);
+ if (unlikely(ret))
+ goto out_free;
+
+ ret = io_iter_do_read(req, iter);
+
+ if (!ret) {
+ goto done;
+ } else if (ret == -EIOCBQUEUED) {
+ ret = 0;
+ goto out_free;
+ } else if (ret == -EAGAIN) {
+ /* IOPOLL retry should happen for io-wq threads */
+ if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
+ goto done;
+ /* no retry on NONBLOCK marked file */
+ if (req->file->f_flags & O_NONBLOCK)
+ goto done;
+ /* some cases will consume bytes even on error returns */
+ iov_iter_revert(iter, io_size - iov_iter_count(iter));
+ ret = 0;
+ goto copy_iov;
+ } else if (ret < 0) {
+ /* make sure -ERESTARTSYS -> -EINTR is done */
+ goto done;
+ }
+
+ /* read it all, or we did blocking attempt. no retry. */
+ if (!iov_iter_count(iter) || !force_nonblock ||
+ (req->file->f_flags & O_NONBLOCK) || !(req->flags & REQ_F_ISREG))
+ goto done;
+
+ io_size -= ret;
+copy_iov:
+ ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
+ if (ret2) {
+ ret = ret2;
goto out_free;
}
+ if (no_async)
+ return -EAGAIN;
+ rw = req->async_data;
+ /* it's copied and will be cleaned with ->io */
+ iovec = NULL;
+ /* now use our persistent iterator, if we aren't already */
+ iter = &rw->iter;
+retry:
+ rw->bytes_done += ret;
+ /* if we can retry, do so with the callbacks armed */
+ if (!io_rw_should_retry(req)) {
+ kiocb->ki_flags &= ~IOCB_WAITQ;
+ return -EAGAIN;
+ }
- ret = rw_verify_area(WRITE, file, &kiocb->ki_pos, iov_count);
- if (!ret) {
- ssize_t ret2;
+ /*
+ * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
+ * get -EIOCBQUEUED, then we'll get a notification when the desired
+ * page gets unlocked. We can also get a partial read here, and if we
+ * do, then just retry at the new offset.
+ */
+ ret = io_iter_do_read(req, iter);
+ if (ret == -EIOCBQUEUED) {
+ ret = 0;
+ goto out_free;
+ } else if (ret > 0 && ret < io_size) {
+ /* we got some bytes, but not all. retry. */
+ kiocb->ki_flags &= ~IOCB_WAITQ;
+ goto retry;
+ }
+done:
+ kiocb_done(kiocb, ret, cs);
+ ret = 0;
+out_free:
+ /* it's reportedly faster than delegating the null check to kfree() */
+ if (iovec)
+ kfree(iovec);
+ return ret;
+}
- /*
- * Open-code file_start_write here to grab freeze protection,
- * which will be released by another thread in
- * io_complete_rw(). Fool lockdep by telling it the lock got
- * released so that it doesn't complain about the held lock when
- * we return to userspace.
- */
- if (req->flags & REQ_F_ISREG) {
- __sb_start_write(file_inode(file)->i_sb,
- SB_FREEZE_WRITE, true);
- __sb_writers_release(file_inode(file)->i_sb,
- SB_FREEZE_WRITE);
- }
- kiocb->ki_flags |= IOCB_WRITE;
+static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ ssize_t ret;
- if (!force_nonblock)
- current->signal->rlim[RLIMIT_FSIZE].rlim_cur = req->fsize;
+ ret = io_prep_rw(req, sqe);
+ if (ret)
+ return ret;
- if (file->f_op->write_iter)
- ret2 = call_write_iter(file, kiocb, &iter);
- else if (req->file->f_op->write)
- ret2 = loop_rw_iter(WRITE, file, kiocb, &iter);
- else
- ret2 = -EINVAL;
+ if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
+ return -EBADF;
- if (!force_nonblock)
- current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
+ /* either don't need iovec imported or already have it */
+ if (!req->async_data)
+ return 0;
+ return io_rw_prep_async(req, WRITE);
+}
- if (!force_nonblock || ret2 != -EAGAIN) {
- io_rw_done(kiocb, ret2);
- } else {
- /*
- * If ->needs_lock is true, we're already in async
- * context.
- */
- if (!s->needs_lock)
- io_async_list_note(WRITE, req, iov_count);
- ret = -EAGAIN;
- }
+static int io_write(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
+ struct kiocb *kiocb = &req->rw.kiocb;
+ struct iov_iter __iter, *iter = &__iter;
+ struct io_async_rw *rw = req->async_data;
+ ssize_t ret, ret2, io_size;
+
+ if (rw)
+ iter = &rw->iter;
+
+ ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
+ if (ret < 0)
+ return ret;
+ io_size = iov_iter_count(iter);
+ req->result = io_size;
+
+ /* Ensure we clear previously set non-block flag */
+ if (!force_nonblock)
+ kiocb->ki_flags &= ~IOCB_NOWAIT;
+ else
+ kiocb->ki_flags |= IOCB_NOWAIT;
+
+ /* If the file doesn't support async, just async punt */
+ if (force_nonblock && !io_file_supports_async(req->file, WRITE))
+ goto copy_iov;
+
+ /* file path doesn't support NOWAIT for non-direct_IO */
+ if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
+ (req->flags & REQ_F_ISREG))
+ goto copy_iov;
+
+ ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size);
+ if (unlikely(ret))
+ goto out_free;
+
+ /*
+ * Open-code file_start_write here to grab freeze protection,
+ * which will be released by another thread in
+ * io_complete_rw(). Fool lockdep by telling it the lock got
+ * released so that it doesn't complain about the held lock when
+ * we return to userspace.
+ */
+ if (req->flags & REQ_F_ISREG) {
+ sb_start_write(file_inode(req->file)->i_sb);
+ __sb_writers_release(file_inode(req->file)->i_sb,
+ SB_FREEZE_WRITE);
+ }
+ kiocb->ki_flags |= IOCB_WRITE;
+
+ if (req->file->f_op->write_iter)
+ ret2 = call_write_iter(req->file, kiocb, iter);
+ else if (req->file->f_op->write)
+ ret2 = loop_rw_iter(WRITE, req, iter);
+ else
+ ret2 = -EINVAL;
+
+ /*
+ * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
+ * retry them without IOCB_NOWAIT.
+ */
+ if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
+ ret2 = -EAGAIN;
+ /* no retry on NONBLOCK marked file */
+ if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK))
+ goto done;
+ if (!force_nonblock || ret2 != -EAGAIN) {
+ /* IOPOLL retry should happen for io-wq threads */
+ if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
+ goto copy_iov;
+done:
+ kiocb_done(kiocb, ret2, cs);
+ } else {
+copy_iov:
+ /* some cases will consume bytes even on error returns */
+ iov_iter_revert(iter, io_size - iov_iter_count(iter));
+ ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
+ if (!ret)
+ return -EAGAIN;
}
out_free:
- kfree(iovec);
+ /* it's reportedly faster than delegating the null check to kfree() */
+ if (iovec)
+ kfree(iovec);
return ret;
}
+static int __io_splice_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ struct io_splice* sp = &req->splice;
+ unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
+
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+
+ sp->file_in = NULL;
+ sp->len = READ_ONCE(sqe->len);
+ sp->flags = READ_ONCE(sqe->splice_flags);
+
+ if (unlikely(sp->flags & ~valid_flags))
+ return -EINVAL;
+
+ sp->file_in = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in),
+ (sp->flags & SPLICE_F_FD_IN_FIXED));
+ if (!sp->file_in)
+ return -EBADF;
+ req->flags |= REQ_F_NEED_CLEANUP;
+
+ if (!S_ISREG(file_inode(sp->file_in)->i_mode)) {
+ /*
+ * Splice operation will be punted aync, and here need to
+ * modify io_wq_work.flags, so initialize io_wq_work firstly.
+ */
+ io_req_init_async(req);
+ req->work.flags |= IO_WQ_WORK_UNBOUND;
+ }
+
+ return 0;
+}
+
+static int io_tee_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
+ return -EINVAL;
+ return __io_splice_prep(req, sqe);
+}
+
+static int io_tee(struct io_kiocb *req, bool force_nonblock)
+{
+ struct io_splice *sp = &req->splice;
+ struct file *in = sp->file_in;
+ struct file *out = sp->file_out;
+ unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
+ long ret = 0;
+
+ if (force_nonblock)
+ return -EAGAIN;
+ if (sp->len)
+ ret = do_tee(in, out, sp->len, flags);
+
+ io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+
+ if (ret != sp->len)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ struct io_splice* sp = &req->splice;
+
+ sp->off_in = READ_ONCE(sqe->splice_off_in);
+ sp->off_out = READ_ONCE(sqe->off);
+ return __io_splice_prep(req, sqe);
+}
+
+static int io_splice(struct io_kiocb *req, bool force_nonblock)
+{
+ struct io_splice *sp = &req->splice;
+ struct file *in = sp->file_in;
+ struct file *out = sp->file_out;
+ unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
+ loff_t *poff_in, *poff_out;
+ long ret = 0;
+
+ if (force_nonblock)
+ return -EAGAIN;
+
+ poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
+ poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
+
+ if (sp->len)
+ ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
+
+ io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+
+ if (ret != sp->len)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
+
/*
* IORING_OP_NOP just posts a completion event, nothing else.
*/
-static int io_nop(struct io_kiocb *req, u64 user_data)
+static int io_nop(struct io_kiocb *req, struct io_comp_state *cs)
{
struct io_ring_ctx *ctx = req->ctx;
- long err = 0;
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
- io_cqring_add_event(ctx, user_data, err);
- io_put_req(req);
+ __io_req_complete(req, 0, 0, cs);
return 0;
}
@@ -1579,376 +3761,1745 @@
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
- if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
+ if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
+ sqe->splice_fd_in))
return -EINVAL;
+ req->sync.flags = READ_ONCE(sqe->fsync_flags);
+ if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
+ return -EINVAL;
+
+ req->sync.off = READ_ONCE(sqe->off);
+ req->sync.len = READ_ONCE(sqe->len);
return 0;
}
-static int io_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- bool force_nonblock)
+static int io_fsync(struct io_kiocb *req, bool force_nonblock)
{
- loff_t sqe_off = READ_ONCE(sqe->off);
- loff_t sqe_len = READ_ONCE(sqe->len);
- loff_t end = sqe_off + sqe_len;
- unsigned fsync_flags;
+ loff_t end = req->sync.off + req->sync.len;
int ret;
- fsync_flags = READ_ONCE(sqe->fsync_flags);
- if (unlikely(fsync_flags & ~IORING_FSYNC_DATASYNC))
- return -EINVAL;
-
- ret = io_prep_fsync(req, sqe);
- if (ret)
- return ret;
-
/* fsync always requires a blocking context */
if (force_nonblock)
return -EAGAIN;
- ret = vfs_fsync_range(req->rw.ki_filp, sqe_off,
+ ret = vfs_fsync_range(req->file, req->sync.off,
end > 0 ? end : LLONG_MAX,
- fsync_flags & IORING_FSYNC_DATASYNC);
+ req->sync.flags & IORING_FSYNC_DATASYNC);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
- if (ret < 0 && (req->flags & REQ_F_LINK))
- req->flags |= REQ_F_FAIL_LINK;
- io_cqring_add_event(req->ctx, sqe->user_data, ret);
- io_put_req(req);
+static int io_fallocate_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ if (sqe->ioprio || sqe->buf_index || sqe->rw_flags ||
+ sqe->splice_fd_in)
+ return -EINVAL;
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+
+ req->sync.off = READ_ONCE(sqe->off);
+ req->sync.len = READ_ONCE(sqe->addr);
+ req->sync.mode = READ_ONCE(sqe->len);
+ return 0;
+}
+
+static int io_fallocate(struct io_kiocb *req, bool force_nonblock)
+{
+ int ret;
+
+ /* fallocate always requiring blocking context */
+ if (force_nonblock)
+ return -EAGAIN;
+ ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
+ req->sync.len);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ const char __user *fname;
+ int ret;
+
+ if (unlikely(sqe->ioprio || sqe->buf_index || sqe->splice_fd_in))
+ return -EINVAL;
+ if (unlikely(req->flags & REQ_F_FIXED_FILE))
+ return -EBADF;
+
+ /* open.how should be already initialised */
+ if (!(req->open.how.flags & O_PATH) && force_o_largefile())
+ req->open.how.flags |= O_LARGEFILE;
+
+ req->open.dfd = READ_ONCE(sqe->fd);
+ fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ req->open.filename = getname(fname);
+ if (IS_ERR(req->open.filename)) {
+ ret = PTR_ERR(req->open.filename);
+ req->open.filename = NULL;
+ return ret;
+ }
+ req->open.nofile = rlimit(RLIMIT_NOFILE);
+ req->open.ignore_nonblock = false;
+ req->flags |= REQ_F_NEED_CLEANUP;
+ return 0;
+}
+
+static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ u64 flags, mode;
+
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+ mode = READ_ONCE(sqe->len);
+ flags = READ_ONCE(sqe->open_flags);
+ req->open.how = build_open_how(flags, mode);
+ return __io_openat_prep(req, sqe);
+}
+
+static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ struct open_how __user *how;
+ size_t len;
+ int ret;
+
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+ how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+ len = READ_ONCE(sqe->len);
+ if (len < OPEN_HOW_SIZE_VER0)
+ return -EINVAL;
+
+ ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
+ len);
+ if (ret)
+ return ret;
+
+ return __io_openat_prep(req, sqe);
+}
+
+static int io_openat2(struct io_kiocb *req, bool force_nonblock)
+{
+ struct open_flags op;
+ struct file *file;
+ int ret;
+
+ if (force_nonblock && !req->open.ignore_nonblock)
+ return -EAGAIN;
+
+ ret = build_open_flags(&req->open.how, &op);
+ if (ret)
+ goto err;
+
+ ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
+ if (ret < 0)
+ goto err;
+
+ file = do_filp_open(req->open.dfd, req->open.filename, &op);
+ if (IS_ERR(file)) {
+ put_unused_fd(ret);
+ ret = PTR_ERR(file);
+ /*
+ * A work-around to ensure that /proc/self works that way
+ * that it should - if we get -EOPNOTSUPP back, then assume
+ * that proc_self_get_link() failed us because we're in async
+ * context. We should be safe to retry this from the task
+ * itself with force_nonblock == false set, as it should not
+ * block on lookup. Would be nice to know this upfront and
+ * avoid the async dance, but doesn't seem feasible.
+ */
+ if (ret == -EOPNOTSUPP && io_wq_current_is_worker()) {
+ req->open.ignore_nonblock = true;
+ refcount_inc(&req->refs);
+ io_req_task_queue(req);
+ return 0;
+ }
+ } else {
+ fsnotify_open(file);
+ fd_install(ret, file);
+ }
+err:
+ putname(req->open.filename);
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int io_openat(struct io_kiocb *req, bool force_nonblock)
+{
+ return io_openat2(req, force_nonblock);
+}
+
+static int io_remove_buffers_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ struct io_provide_buf *p = &req->pbuf;
+ u64 tmp;
+
+ if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
+ sqe->splice_fd_in)
+ return -EINVAL;
+
+ tmp = READ_ONCE(sqe->fd);
+ if (!tmp || tmp > USHRT_MAX)
+ return -EINVAL;
+
+ memset(p, 0, sizeof(*p));
+ p->nbufs = tmp;
+ p->bgid = READ_ONCE(sqe->buf_group);
+ return 0;
+}
+
+static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
+ int bgid, unsigned nbufs)
+{
+ unsigned i = 0;
+
+ /* shouldn't happen */
+ if (!nbufs)
+ return 0;
+
+ /* the head kbuf is the list itself */
+ while (!list_empty(&buf->list)) {
+ struct io_buffer *nxt;
+
+ nxt = list_first_entry(&buf->list, struct io_buffer, list);
+ list_del(&nxt->list);
+ kfree(nxt);
+ if (++i == nbufs)
+ return i;
+ }
+ i++;
+ kfree(buf);
+ xa_erase(&ctx->io_buffers, bgid);
+
+ return i;
+}
+
+static int io_remove_buffers(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_provide_buf *p = &req->pbuf;
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_buffer *head;
+ int ret = 0;
+
+ io_ring_submit_lock(ctx, !force_nonblock);
+
+ lockdep_assert_held(&ctx->uring_lock);
+
+ ret = -ENOENT;
+ head = xa_load(&ctx->io_buffers, p->bgid);
+ if (head)
+ ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
+ if (ret < 0)
+ req_set_fail_links(req);
+
+ /* need to hold the lock to complete IOPOLL requests */
+ if (ctx->flags & IORING_SETUP_IOPOLL) {
+ __io_req_complete(req, ret, 0, cs);
+ io_ring_submit_unlock(ctx, !force_nonblock);
+ } else {
+ io_ring_submit_unlock(ctx, !force_nonblock);
+ __io_req_complete(req, ret, 0, cs);
+ }
+ return 0;
+}
+
+static int io_provide_buffers_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ unsigned long size, tmp_check;
+ struct io_provide_buf *p = &req->pbuf;
+ u64 tmp;
+
+ if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
+ return -EINVAL;
+
+ tmp = READ_ONCE(sqe->fd);
+ if (!tmp || tmp > USHRT_MAX)
+ return -E2BIG;
+ p->nbufs = tmp;
+ p->addr = READ_ONCE(sqe->addr);
+ p->len = READ_ONCE(sqe->len);
+
+ if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
+ &size))
+ return -EOVERFLOW;
+ if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
+ return -EOVERFLOW;
+
+ size = (unsigned long)p->len * p->nbufs;
+ if (!access_ok(u64_to_user_ptr(p->addr), size))
+ return -EFAULT;
+
+ p->bgid = READ_ONCE(sqe->buf_group);
+ tmp = READ_ONCE(sqe->off);
+ if (tmp > USHRT_MAX)
+ return -E2BIG;
+ p->bid = tmp;
+ return 0;
+}
+
+static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
+{
+ struct io_buffer *buf;
+ u64 addr = pbuf->addr;
+ int i, bid = pbuf->bid;
+
+ for (i = 0; i < pbuf->nbufs; i++) {
+ buf = kmalloc(sizeof(*buf), GFP_KERNEL_ACCOUNT);
+ if (!buf)
+ break;
+
+ buf->addr = addr;
+ buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
+ buf->bid = bid;
+ addr += pbuf->len;
+ bid++;
+ if (!*head) {
+ INIT_LIST_HEAD(&buf->list);
+ *head = buf;
+ } else {
+ list_add_tail(&buf->list, &(*head)->list);
+ }
+ cond_resched();
+ }
+
+ return i ? i : -ENOMEM;
+}
+
+static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_provide_buf *p = &req->pbuf;
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_buffer *head, *list;
+ int ret = 0;
+
+ io_ring_submit_lock(ctx, !force_nonblock);
+
+ lockdep_assert_held(&ctx->uring_lock);
+
+ list = head = xa_load(&ctx->io_buffers, p->bgid);
+
+ ret = io_add_buffers(p, &head);
+ if (ret >= 0 && !list) {
+ ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
+ if (ret < 0)
+ __io_remove_buffers(ctx, head, p->bgid, -1U);
+ }
+ if (ret < 0)
+ req_set_fail_links(req);
+
+ /* need to hold the lock to complete IOPOLL requests */
+ if (ctx->flags & IORING_SETUP_IOPOLL) {
+ __io_req_complete(req, ret, 0, cs);
+ io_ring_submit_unlock(ctx, !force_nonblock);
+ } else {
+ io_ring_submit_unlock(ctx, !force_nonblock);
+ __io_req_complete(req, ret, 0, cs);
+ }
+ return 0;
+}
+
+static int io_epoll_ctl_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+#if defined(CONFIG_EPOLL)
+ if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+ return -EINVAL;
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+
+ req->epoll.epfd = READ_ONCE(sqe->fd);
+ req->epoll.op = READ_ONCE(sqe->len);
+ req->epoll.fd = READ_ONCE(sqe->off);
+
+ if (ep_op_has_event(req->epoll.op)) {
+ struct epoll_event __user *ev;
+
+ ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
+ return -EFAULT;
+ }
+
+ return 0;
+#else
+ return -EOPNOTSUPP;
+#endif
+}
+
+static int io_epoll_ctl(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+#if defined(CONFIG_EPOLL)
+ struct io_epoll *ie = &req->epoll;
+ int ret;
+
+ ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
+ if (force_nonblock && ret == -EAGAIN)
+ return -EAGAIN;
+
+ if (ret < 0)
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, 0, cs);
+ return 0;
+#else
+ return -EOPNOTSUPP;
+#endif
+}
+
+static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
+ if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->splice_fd_in)
+ return -EINVAL;
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+
+ req->madvise.addr = READ_ONCE(sqe->addr);
+ req->madvise.len = READ_ONCE(sqe->len);
+ req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
+ return 0;
+#else
+ return -EOPNOTSUPP;
+#endif
+}
+
+static int io_madvise(struct io_kiocb *req, bool force_nonblock)
+{
+#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
+ struct io_madvise *ma = &req->madvise;
+ int ret;
+
+ if (force_nonblock)
+ return -EAGAIN;
+
+ ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+#else
+ return -EOPNOTSUPP;
+#endif
+}
+
+static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ if (sqe->ioprio || sqe->buf_index || sqe->addr || sqe->splice_fd_in)
+ return -EINVAL;
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+
+ req->fadvise.offset = READ_ONCE(sqe->off);
+ req->fadvise.len = READ_ONCE(sqe->len);
+ req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
+ return 0;
+}
+
+static int io_fadvise(struct io_kiocb *req, bool force_nonblock)
+{
+ struct io_fadvise *fa = &req->fadvise;
+ int ret;
+
+ if (force_nonblock) {
+ switch (fa->advice) {
+ case POSIX_FADV_NORMAL:
+ case POSIX_FADV_RANDOM:
+ case POSIX_FADV_SEQUENTIAL:
+ break;
+ default:
+ return -EAGAIN;
+ }
+ }
+
+ ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+ return -EINVAL;
+ if (req->flags & REQ_F_FIXED_FILE)
+ return -EBADF;
+
+ req->statx.dfd = READ_ONCE(sqe->fd);
+ req->statx.mask = READ_ONCE(sqe->len);
+ req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+ req->statx.flags = READ_ONCE(sqe->statx_flags);
+
+ return 0;
+}
+
+static int io_statx(struct io_kiocb *req, bool force_nonblock)
+{
+ struct io_statx *ctx = &req->statx;
+ int ret;
+
+ if (force_nonblock) {
+ /* only need file table for an actual valid fd */
+ if (ctx->dfd == -1 || ctx->dfd == AT_FDCWD)
+ req->flags |= REQ_F_NO_FILE_TABLE;
+ return -EAGAIN;
+ }
+
+ ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
+ ctx->buffer);
+
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ /*
+ * If we queue this for async, it must not be cancellable. That would
+ * leave the 'file' in an undeterminate state, and here need to modify
+ * io_wq_work.flags, so initialize io_wq_work firstly.
+ */
+ io_req_init_async(req);
+
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
+ sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
+ return -EINVAL;
+ if (req->flags & REQ_F_FIXED_FILE)
+ return -EBADF;
+
+ req->close.fd = READ_ONCE(sqe->fd);
+ if ((req->file && req->file->f_op == &io_uring_fops))
+ return -EBADF;
+
+ req->close.put_file = NULL;
+ return 0;
+}
+
+static int io_close(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_close *close = &req->close;
+ int ret;
+
+ /* might be already done during nonblock submission */
+ if (!close->put_file) {
+ ret = __close_fd_get_file(close->fd, &close->put_file);
+ if (ret < 0)
+ return (ret == -ENOENT) ? -EBADF : ret;
+ }
+
+ /* if the file has a flush method, be safe and punt to async */
+ if (close->put_file->f_op->flush && force_nonblock) {
+ /* not safe to cancel at this point */
+ req->work.flags |= IO_WQ_WORK_NO_CANCEL;
+ /* was never set, but play safe */
+ req->flags &= ~REQ_F_NOWAIT;
+ /* avoid grabbing files - we don't need the files */
+ req->flags |= REQ_F_NO_FILE_TABLE;
+ return -EAGAIN;
+ }
+
+ /* No ->flush() or already async, safely close from here */
+ ret = filp_close(close->put_file, req->work.identity->files);
+ if (ret < 0)
+ req_set_fail_links(req);
+ fput(close->put_file);
+ close->put_file = NULL;
+ __io_req_complete(req, ret, 0, cs);
return 0;
}
static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_ring_ctx *ctx = req->ctx;
- int ret = 0;
if (!req->file)
return -EBADF;
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
- if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
+ if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
+ sqe->splice_fd_in))
return -EINVAL;
- return ret;
+ req->sync.off = READ_ONCE(sqe->off);
+ req->sync.len = READ_ONCE(sqe->len);
+ req->sync.flags = READ_ONCE(sqe->sync_range_flags);
+ return 0;
}
-static int io_sync_file_range(struct io_kiocb *req,
- const struct io_uring_sqe *sqe,
- bool force_nonblock)
+static int io_sync_file_range(struct io_kiocb *req, bool force_nonblock)
{
- loff_t sqe_off;
- loff_t sqe_len;
- unsigned flags;
int ret;
- ret = io_prep_sfr(req, sqe);
- if (ret)
- return ret;
-
/* sync_file_range always requires a blocking context */
if (force_nonblock)
return -EAGAIN;
- sqe_off = READ_ONCE(sqe->off);
- sqe_len = READ_ONCE(sqe->len);
- flags = READ_ONCE(sqe->sync_range_flags);
-
- ret = sync_file_range(req->rw.ki_filp, sqe_off, sqe_len, flags);
-
- if (ret < 0 && (req->flags & REQ_F_LINK))
- req->flags |= REQ_F_FAIL_LINK;
- io_cqring_add_event(req->ctx, sqe->user_data, ret);
- io_put_req(req);
+ ret = sync_file_range(req->file, req->sync.off, req->sync.len,
+ req->sync.flags);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
return 0;
}
#if defined(CONFIG_NET)
-static int io_send_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- bool force_nonblock,
- long (*fn)(struct socket *, struct user_msghdr __user *,
- unsigned int))
+static int io_setup_async_msg(struct io_kiocb *req,
+ struct io_async_msghdr *kmsg)
{
- struct socket *sock;
+ struct io_async_msghdr *async_msg = req->async_data;
+
+ if (async_msg)
+ return -EAGAIN;
+ if (io_alloc_async_data(req)) {
+ if (kmsg->iov != kmsg->fast_iov)
+ kfree(kmsg->iov);
+ return -ENOMEM;
+ }
+ async_msg = req->async_data;
+ req->flags |= REQ_F_NEED_CLEANUP;
+ memcpy(async_msg, kmsg, sizeof(*kmsg));
+ return -EAGAIN;
+}
+
+static int io_sendmsg_copy_hdr(struct io_kiocb *req,
+ struct io_async_msghdr *iomsg)
+{
+ iomsg->iov = iomsg->fast_iov;
+ iomsg->msg.msg_name = &iomsg->addr;
+ return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
+ req->sr_msg.msg_flags, &iomsg->iov);
+}
+
+static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ struct io_async_msghdr *async_msg = req->async_data;
+ struct io_sr_msg *sr = &req->sr_msg;
int ret;
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
- sock = sock_from_file(req->file, &ret);
- if (sock) {
- struct user_msghdr __user *msg;
- unsigned flags;
-
- flags = READ_ONCE(sqe->msg_flags);
- if (flags & MSG_DONTWAIT)
- req->flags |= REQ_F_NOWAIT;
- else if (force_nonblock)
- flags |= MSG_DONTWAIT;
+ sr->msg_flags = READ_ONCE(sqe->msg_flags);
+ sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ sr->len = READ_ONCE(sqe->len);
#ifdef CONFIG_COMPAT
- if (req->ctx->compat)
- flags |= MSG_CMSG_COMPAT;
+ if (req->ctx->compat)
+ sr->msg_flags |= MSG_CMSG_COMPAT;
#endif
- msg = (struct user_msghdr __user *) (unsigned long)
- READ_ONCE(sqe->addr);
+ if (!async_msg || !io_op_defs[req->opcode].needs_async_data)
+ return 0;
+ ret = io_sendmsg_copy_hdr(req, async_msg);
+ if (!ret)
+ req->flags |= REQ_F_NEED_CLEANUP;
+ return ret;
+}
- ret = fn(sock, msg, flags);
- if (force_nonblock && ret == -EAGAIN)
+static int io_sendmsg(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_async_msghdr iomsg, *kmsg;
+ struct socket *sock;
+ unsigned flags;
+ int min_ret = 0;
+ int ret;
+
+ sock = sock_from_file(req->file, &ret);
+ if (unlikely(!sock))
+ return ret;
+
+ if (req->async_data) {
+ kmsg = req->async_data;
+ kmsg->msg.msg_name = &kmsg->addr;
+ /* if iov is set, it's allocated already */
+ if (!kmsg->iov)
+ kmsg->iov = kmsg->fast_iov;
+ kmsg->msg.msg_iter.iov = kmsg->iov;
+ } else {
+ ret = io_sendmsg_copy_hdr(req, &iomsg);
+ if (ret)
return ret;
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
+ kmsg = &iomsg;
}
- if (req->fs) {
- struct fs_struct *fs = req->fs;
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
+ if (flags & MSG_DONTWAIT)
+ req->flags |= REQ_F_NOWAIT;
+ else if (force_nonblock)
+ flags |= MSG_DONTWAIT;
- spin_lock(&req->fs->lock);
- if (--fs->users)
- fs = NULL;
- spin_unlock(&req->fs->lock);
- if (fs)
- free_fs_struct(fs);
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
+ ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
+ if (force_nonblock && ret == -EAGAIN)
+ return io_setup_async_msg(req, kmsg);
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+
+ if (kmsg->iov != kmsg->fast_iov)
+ kfree(kmsg->iov);
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ if (ret < min_ret)
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, 0, cs);
+ return 0;
+}
+
+static int io_send(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct msghdr msg;
+ struct iovec iov;
+ struct socket *sock;
+ unsigned flags;
+ int min_ret = 0;
+ int ret;
+
+ sock = sock_from_file(req->file, &ret);
+ if (unlikely(!sock))
+ return ret;
+
+ ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
+ if (unlikely(ret))
+ return ret;
+
+ msg.msg_name = NULL;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_namelen = 0;
+
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
+ if (flags & MSG_DONTWAIT)
+ req->flags |= REQ_F_NOWAIT;
+ else if (force_nonblock)
+ flags |= MSG_DONTWAIT;
+
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&msg.msg_iter);
+
+ msg.msg_flags = flags;
+ ret = sock_sendmsg(sock, &msg);
+ if (force_nonblock && ret == -EAGAIN)
+ return -EAGAIN;
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+
+ if (ret < min_ret)
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, 0, cs);
+ return 0;
+}
+
+static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
+ struct io_async_msghdr *iomsg)
+{
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct iovec __user *uiov;
+ size_t iov_len;
+ int ret;
+
+ ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
+ &iomsg->uaddr, &uiov, &iov_len);
+ if (ret)
+ return ret;
+
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ if (iov_len > 1)
+ return -EINVAL;
+ if (copy_from_user(iomsg->iov, uiov, sizeof(*uiov)))
+ return -EFAULT;
+ sr->len = iomsg->iov[0].iov_len;
+ iov_iter_init(&iomsg->msg.msg_iter, READ, iomsg->iov, 1,
+ sr->len);
+ iomsg->iov = NULL;
+ } else {
+ ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
+ &iomsg->iov, &iomsg->msg.msg_iter,
+ false);
+ if (ret > 0)
+ ret = 0;
}
- io_cqring_add_event(req->ctx, sqe->user_data, ret);
- io_put_req(req);
+
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
+ struct io_async_msghdr *iomsg)
+{
+ struct compat_msghdr __user *msg_compat;
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct compat_iovec __user *uiov;
+ compat_uptr_t ptr;
+ compat_size_t len;
+ int ret;
+
+ msg_compat = (struct compat_msghdr __user *) sr->umsg;
+ ret = __get_compat_msghdr(&iomsg->msg, msg_compat, &iomsg->uaddr,
+ &ptr, &len);
+ if (ret)
+ return ret;
+
+ uiov = compat_ptr(ptr);
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ compat_ssize_t clen;
+
+ if (len > 1)
+ return -EINVAL;
+ if (!access_ok(uiov, sizeof(*uiov)))
+ return -EFAULT;
+ if (__get_user(clen, &uiov->iov_len))
+ return -EFAULT;
+ if (clen < 0)
+ return -EINVAL;
+ sr->len = clen;
+ iomsg->iov[0].iov_len = clen;
+ iomsg->iov = NULL;
+ } else {
+ ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
+ UIO_FASTIOV, &iomsg->iov,
+ &iomsg->msg.msg_iter, true);
+ if (ret < 0)
+ return ret;
+ }
+
return 0;
}
#endif
-static int io_sendmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- bool force_nonblock)
+static int io_recvmsg_copy_hdr(struct io_kiocb *req,
+ struct io_async_msghdr *iomsg)
{
-#if defined(CONFIG_NET)
- return io_send_recvmsg(req, sqe, force_nonblock, __sys_sendmsg_sock);
-#else
- return -EOPNOTSUPP;
+ iomsg->msg.msg_name = &iomsg->addr;
+ iomsg->iov = iomsg->fast_iov;
+
+#ifdef CONFIG_COMPAT
+ if (req->ctx->compat)
+ return __io_compat_recvmsg_copy_hdr(req, iomsg);
#endif
+
+ return __io_recvmsg_copy_hdr(req, iomsg);
}
-static int io_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- bool force_nonblock)
+static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
+ bool needs_lock)
{
-#if defined(CONFIG_NET)
- return io_send_recvmsg(req, sqe, force_nonblock, __sys_recvmsg_sock);
-#else
- return -EOPNOTSUPP;
-#endif
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct io_buffer *kbuf;
+
+ kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
+ if (IS_ERR(kbuf))
+ return kbuf;
+
+ sr->kbuf = kbuf;
+ req->flags |= REQ_F_BUFFER_SELECTED;
+ return kbuf;
}
-static void io_poll_remove_one(struct io_kiocb *req)
+static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
{
- struct io_poll_iocb *poll = &req->poll;
+ return io_put_kbuf(req, req->sr_msg.kbuf);
+}
+
+static int io_recvmsg_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ struct io_async_msghdr *async_msg = req->async_data;
+ struct io_sr_msg *sr = &req->sr_msg;
+ int ret;
+
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+
+ sr->msg_flags = READ_ONCE(sqe->msg_flags);
+ sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ sr->len = READ_ONCE(sqe->len);
+ sr->bgid = READ_ONCE(sqe->buf_group);
+
+#ifdef CONFIG_COMPAT
+ if (req->ctx->compat)
+ sr->msg_flags |= MSG_CMSG_COMPAT;
+#endif
+
+ if (!async_msg || !io_op_defs[req->opcode].needs_async_data)
+ return 0;
+ ret = io_recvmsg_copy_hdr(req, async_msg);
+ if (!ret)
+ req->flags |= REQ_F_NEED_CLEANUP;
+ return ret;
+}
+
+static int io_recvmsg(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_async_msghdr iomsg, *kmsg;
+ struct socket *sock;
+ struct io_buffer *kbuf;
+ unsigned flags;
+ int min_ret = 0;
+ int ret, cflags = 0;
+
+ sock = sock_from_file(req->file, &ret);
+ if (unlikely(!sock))
+ return ret;
+
+ if (req->async_data) {
+ kmsg = req->async_data;
+ kmsg->msg.msg_name = &kmsg->addr;
+ /* if iov is set, it's allocated already */
+ if (!kmsg->iov)
+ kmsg->iov = kmsg->fast_iov;
+ kmsg->msg.msg_iter.iov = kmsg->iov;
+ } else {
+ ret = io_recvmsg_copy_hdr(req, &iomsg);
+ if (ret)
+ return ret;
+ kmsg = &iomsg;
+ }
+
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ kbuf = io_recv_buffer_select(req, !force_nonblock);
+ if (IS_ERR(kbuf))
+ return PTR_ERR(kbuf);
+ kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
+ iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->iov,
+ 1, req->sr_msg.len);
+ }
+
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
+ if (flags & MSG_DONTWAIT)
+ req->flags |= REQ_F_NOWAIT;
+ else if (force_nonblock)
+ flags |= MSG_DONTWAIT;
+
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
+ ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
+ kmsg->uaddr, flags);
+ if (force_nonblock && ret == -EAGAIN)
+ return io_setup_async_msg(req, kmsg);
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+
+ if (req->flags & REQ_F_BUFFER_SELECTED)
+ cflags = io_put_recv_kbuf(req);
+ if (kmsg->iov != kmsg->fast_iov)
+ kfree(kmsg->iov);
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, cflags, cs);
+ return 0;
+}
+
+static int io_recv(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_buffer *kbuf;
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct msghdr msg;
+ void __user *buf = sr->buf;
+ struct socket *sock;
+ struct iovec iov;
+ unsigned flags;
+ int min_ret = 0;
+ int ret, cflags = 0;
+
+ sock = sock_from_file(req->file, &ret);
+ if (unlikely(!sock))
+ return ret;
+
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ kbuf = io_recv_buffer_select(req, !force_nonblock);
+ if (IS_ERR(kbuf))
+ return PTR_ERR(kbuf);
+ buf = u64_to_user_ptr(kbuf->addr);
+ }
+
+ ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
+ if (unlikely(ret))
+ goto out_free;
+
+ msg.msg_name = NULL;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_namelen = 0;
+ msg.msg_iocb = NULL;
+ msg.msg_flags = 0;
+
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
+ if (flags & MSG_DONTWAIT)
+ req->flags |= REQ_F_NOWAIT;
+ else if (force_nonblock)
+ flags |= MSG_DONTWAIT;
+
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&msg.msg_iter);
+
+ ret = sock_recvmsg(sock, &msg, flags);
+ if (force_nonblock && ret == -EAGAIN)
+ return -EAGAIN;
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+out_free:
+ if (req->flags & REQ_F_BUFFER_SELECTED)
+ cflags = io_put_recv_kbuf(req);
+ if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, cflags, cs);
+ return 0;
+}
+
+static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ struct io_accept *accept = &req->accept;
+
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->splice_fd_in)
+ return -EINVAL;
+
+ accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+ accept->flags = READ_ONCE(sqe->accept_flags);
+ accept->nofile = rlimit(RLIMIT_NOFILE);
+ return 0;
+}
+
+static int io_accept(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_accept *accept = &req->accept;
+ unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
+ int ret;
+
+ if (req->file->f_flags & O_NONBLOCK)
+ req->flags |= REQ_F_NOWAIT;
+
+ ret = __sys_accept4_file(req->file, file_flags, accept->addr,
+ accept->addr_len, accept->flags,
+ accept->nofile);
+ if (ret == -EAGAIN && force_nonblock)
+ return -EAGAIN;
+ if (ret < 0) {
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+ req_set_fail_links(req);
+ }
+ __io_req_complete(req, ret, 0, cs);
+ return 0;
+}
+
+static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ struct io_connect *conn = &req->connect;
+ struct io_async_connect *io = req->async_data;
+
+ if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags ||
+ sqe->splice_fd_in)
+ return -EINVAL;
+
+ conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ conn->addr_len = READ_ONCE(sqe->addr2);
+
+ if (!io)
+ return 0;
+
+ return move_addr_to_kernel(conn->addr, conn->addr_len,
+ &io->address);
+}
+
+static int io_connect(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_async_connect __io, *io;
+ unsigned file_flags;
+ int ret;
+
+ if (req->async_data) {
+ io = req->async_data;
+ } else {
+ ret = move_addr_to_kernel(req->connect.addr,
+ req->connect.addr_len,
+ &__io.address);
+ if (ret)
+ goto out;
+ io = &__io;
+ }
+
+ file_flags = force_nonblock ? O_NONBLOCK : 0;
+
+ ret = __sys_connect_file(req->file, &io->address,
+ req->connect.addr_len, file_flags);
+ if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
+ if (req->async_data)
+ return -EAGAIN;
+ if (io_alloc_async_data(req)) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ io = req->async_data;
+ memcpy(req->async_data, &__io, sizeof(__io));
+ return -EAGAIN;
+ }
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+out:
+ if (ret < 0)
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, 0, cs);
+ return 0;
+}
+#else /* !CONFIG_NET */
+static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_sendmsg(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_send(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_recvmsg_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_recvmsg(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_recv(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_accept(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ return -EOPNOTSUPP;
+}
+
+static int io_connect(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ return -EOPNOTSUPP;
+}
+#endif /* CONFIG_NET */
+
+struct io_poll_table {
+ struct poll_table_struct pt;
+ struct io_kiocb *req;
+ int nr_entries;
+ int error;
+};
+
+static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
+ __poll_t mask, task_work_func_t func)
+{
+ bool twa_signal_ok;
+ int ret;
+
+ /* for instances that support it check for an event match first: */
+ if (mask && !(mask & poll->events))
+ return 0;
+
+ trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
+
+ list_del_init(&poll->wait.entry);
+
+ req->result = mask;
+ init_task_work(&req->task_work, func);
+ percpu_ref_get(&req->ctx->refs);
+
+ /*
+ * If we using the signalfd wait_queue_head for this wakeup, then
+ * it's not safe to use TWA_SIGNAL as we could be recursing on the
+ * tsk->sighand->siglock on doing the wakeup. Should not be needed
+ * either, as the normal wakeup will suffice.
+ */
+ twa_signal_ok = (poll->head != &req->task->sighand->signalfd_wqh);
+
+ /*
+ * If this fails, then the task is exiting. When a task exits, the
+ * work gets canceled, so just cancel this request as well instead
+ * of executing it. We can't safely execute it anyway, as we may not
+ * have the needed state needed for it anyway.
+ */
+ ret = io_req_task_work_add(req, twa_signal_ok);
+ if (unlikely(ret)) {
+ struct task_struct *tsk;
+
+ WRITE_ONCE(poll->canceled, true);
+ tsk = io_wq_get_task(req->ctx->io_wq);
+ task_work_add(tsk, &req->task_work, TWA_NONE);
+ wake_up_process(tsk);
+ }
+ return 1;
+}
+
+static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
+ __acquires(&req->ctx->completion_lock)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+
+ if (!req->result && !READ_ONCE(poll->canceled)) {
+ struct poll_table_struct pt = { ._key = poll->events };
+
+ req->result = vfs_poll(req->file, &pt) & poll->events;
+ }
+
+ spin_lock_irq(&ctx->completion_lock);
+ if (!req->result && !READ_ONCE(poll->canceled)) {
+ add_wait_queue(poll->head, &poll->wait);
+ return true;
+ }
+
+ return false;
+}
+
+static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
+{
+ /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
+ if (req->opcode == IORING_OP_POLL_ADD)
+ return req->async_data;
+ return req->apoll->double_poll;
+}
+
+static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
+{
+ if (req->opcode == IORING_OP_POLL_ADD)
+ return &req->poll;
+ return &req->apoll->poll;
+}
+
+static void io_poll_remove_double(struct io_kiocb *req)
+{
+ struct io_poll_iocb *poll = io_poll_get_double(req);
+
+ lockdep_assert_held(&req->ctx->completion_lock);
+
+ if (poll && poll->head) {
+ struct wait_queue_head *head = poll->head;
+
+ spin_lock(&head->lock);
+ list_del_init(&poll->wait.entry);
+ if (poll->wait.private)
+ refcount_dec(&req->refs);
+ poll->head = NULL;
+ spin_unlock(&head->lock);
+ }
+}
+
+static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+
+ io_poll_remove_double(req);
+ req->poll.done = true;
+ io_cqring_fill_event(req, error ? error : mangle_poll(mask));
+ io_commit_cqring(ctx);
+}
+
+static void io_poll_task_func(struct callback_head *cb)
+{
+ struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_kiocb *nxt;
+
+ if (io_poll_rewait(req, &req->poll)) {
+ spin_unlock_irq(&ctx->completion_lock);
+ } else {
+ hash_del(&req->hash_node);
+ io_poll_complete(req, req->result, 0);
+ spin_unlock_irq(&ctx->completion_lock);
+
+ nxt = io_put_req_find_next(req);
+ io_cqring_ev_posted(ctx);
+ if (nxt)
+ __io_req_task_submit(nxt);
+ }
+
+ percpu_ref_put(&ctx->refs);
+}
+
+static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
+ int sync, void *key)
+{
+ struct io_kiocb *req = wait->private;
+ struct io_poll_iocb *poll = io_poll_get_single(req);
+ __poll_t mask = key_to_poll(key);
+
+ /* for instances that support it check for an event match first: */
+ if (mask && !(mask & poll->events))
+ return 0;
+
+ list_del_init(&wait->entry);
+
+ if (poll && poll->head) {
+ bool done;
+
+ spin_lock(&poll->head->lock);
+ done = list_empty(&poll->wait.entry);
+ if (!done)
+ list_del_init(&poll->wait.entry);
+ /* make sure double remove sees this as being gone */
+ wait->private = NULL;
+ spin_unlock(&poll->head->lock);
+ if (!done) {
+ /* use wait func handler, so it matches the rq type */
+ poll->wait.func(&poll->wait, mode, sync, key);
+ }
+ }
+ refcount_dec(&req->refs);
+ return 1;
+}
+
+static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
+ wait_queue_func_t wake_func)
+{
+ poll->head = NULL;
+ poll->done = false;
+ poll->canceled = false;
+ poll->events = events;
+ INIT_LIST_HEAD(&poll->wait.entry);
+ init_waitqueue_func_entry(&poll->wait, wake_func);
+}
+
+static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
+ struct wait_queue_head *head,
+ struct io_poll_iocb **poll_ptr)
+{
+ struct io_kiocb *req = pt->req;
+
+ /*
+ * The file being polled uses multiple waitqueues for poll handling
+ * (e.g. one for read, one for write). Setup a separate io_poll_iocb
+ * if this happens.
+ */
+ if (unlikely(pt->nr_entries)) {
+ struct io_poll_iocb *poll_one = poll;
+
+ /* already have a 2nd entry, fail a third attempt */
+ if (*poll_ptr) {
+ pt->error = -EINVAL;
+ return;
+ }
+ /* double add on the same waitqueue head, ignore */
+ if (poll->head == head)
+ return;
+ poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
+ if (!poll) {
+ pt->error = -ENOMEM;
+ return;
+ }
+ io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
+ refcount_inc(&req->refs);
+ poll->wait.private = req;
+ *poll_ptr = poll;
+ }
+
+ pt->nr_entries++;
+ poll->head = head;
+
+ if (poll->events & EPOLLEXCLUSIVE)
+ add_wait_queue_exclusive(head, &poll->wait);
+ else
+ add_wait_queue(head, &poll->wait);
+}
+
+static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
+ struct poll_table_struct *p)
+{
+ struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
+ struct async_poll *apoll = pt->req->apoll;
+
+ __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
+}
+
+static void io_async_task_func(struct callback_head *cb)
+{
+ struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
+ struct async_poll *apoll = req->apoll;
+ struct io_ring_ctx *ctx = req->ctx;
+
+ trace_io_uring_task_run(req->ctx, req->opcode, req->user_data);
+
+ if (io_poll_rewait(req, &apoll->poll)) {
+ spin_unlock_irq(&ctx->completion_lock);
+ percpu_ref_put(&ctx->refs);
+ return;
+ }
+
+ /* If req is still hashed, it cannot have been canceled. Don't check. */
+ if (hash_hashed(&req->hash_node))
+ hash_del(&req->hash_node);
+
+ io_poll_remove_double(req);
+ spin_unlock_irq(&ctx->completion_lock);
+
+ if (!READ_ONCE(apoll->poll.canceled))
+ __io_req_task_submit(req);
+ else
+ __io_req_task_cancel(req, -ECANCELED);
+
+ percpu_ref_put(&ctx->refs);
+ kfree(apoll->double_poll);
+ kfree(apoll);
+}
+
+static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
+ void *key)
+{
+ struct io_kiocb *req = wait->private;
+ struct io_poll_iocb *poll = &req->apoll->poll;
+
+ trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
+ key_to_poll(key));
+
+ return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
+}
+
+static void io_poll_req_insert(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct hlist_head *list;
+
+ list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
+ hlist_add_head(&req->hash_node, list);
+}
+
+static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
+ struct io_poll_iocb *poll,
+ struct io_poll_table *ipt, __poll_t mask,
+ wait_queue_func_t wake_func)
+ __acquires(&ctx->completion_lock)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ bool cancel = false;
+
+ INIT_HLIST_NODE(&req->hash_node);
+ io_init_poll_iocb(poll, mask, wake_func);
+ poll->file = req->file;
+ poll->wait.private = req;
+
+ ipt->pt._key = mask;
+ ipt->req = req;
+ ipt->error = 0;
+ ipt->nr_entries = 0;
+
+ mask = vfs_poll(req->file, &ipt->pt) & poll->events;
+ if (unlikely(!ipt->nr_entries) && !ipt->error)
+ ipt->error = -EINVAL;
+
+ spin_lock_irq(&ctx->completion_lock);
+ if (ipt->error)
+ io_poll_remove_double(req);
+ if (likely(poll->head)) {
+ spin_lock(&poll->head->lock);
+ if (unlikely(list_empty(&poll->wait.entry))) {
+ if (ipt->error)
+ cancel = true;
+ ipt->error = 0;
+ mask = 0;
+ }
+ if (mask || ipt->error)
+ list_del_init(&poll->wait.entry);
+ else if (cancel)
+ WRITE_ONCE(poll->canceled, true);
+ else if (!poll->done) /* actually waiting for an event */
+ io_poll_req_insert(req);
+ spin_unlock(&poll->head->lock);
+ }
+
+ return mask;
+}
+
+static bool io_arm_poll_handler(struct io_kiocb *req)
+{
+ const struct io_op_def *def = &io_op_defs[req->opcode];
+ struct io_ring_ctx *ctx = req->ctx;
+ struct async_poll *apoll;
+ struct io_poll_table ipt;
+ __poll_t mask, ret;
+ int rw;
+
+ if (!req->file || !file_can_poll(req->file))
+ return false;
+ if (req->flags & REQ_F_POLLED)
+ return false;
+ if (def->pollin)
+ rw = READ;
+ else if (def->pollout)
+ rw = WRITE;
+ else
+ return false;
+ /* if we can't nonblock try, then no point in arming a poll handler */
+ if (!io_file_supports_async(req->file, rw))
+ return false;
+
+ apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
+ if (unlikely(!apoll))
+ return false;
+ apoll->double_poll = NULL;
+
+ req->flags |= REQ_F_POLLED;
+ req->apoll = apoll;
+
+ mask = 0;
+ if (def->pollin)
+ mask |= POLLIN | POLLRDNORM;
+ if (def->pollout)
+ mask |= POLLOUT | POLLWRNORM;
+
+ /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
+ if ((req->opcode == IORING_OP_RECVMSG) &&
+ (req->sr_msg.msg_flags & MSG_ERRQUEUE))
+ mask &= ~POLLIN;
+
+ mask |= POLLERR | POLLPRI;
+
+ ipt.pt._qproc = io_async_queue_proc;
+
+ ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
+ io_async_wake);
+ if (ret || ipt.error) {
+ io_poll_remove_double(req);
+ spin_unlock_irq(&ctx->completion_lock);
+ kfree(apoll->double_poll);
+ kfree(apoll);
+ return false;
+ }
+ spin_unlock_irq(&ctx->completion_lock);
+ trace_io_uring_poll_arm(ctx, req->opcode, req->user_data, mask,
+ apoll->poll.events);
+ return true;
+}
+
+static bool __io_poll_remove_one(struct io_kiocb *req,
+ struct io_poll_iocb *poll)
+{
+ bool do_complete = false;
spin_lock(&poll->head->lock);
WRITE_ONCE(poll->canceled, true);
if (!list_empty(&poll->wait.entry)) {
list_del_init(&poll->wait.entry);
- io_queue_async_work(req->ctx, req);
+ do_complete = true;
}
spin_unlock(&poll->head->lock);
-
- list_del_init(&req->list);
+ hash_del(&req->hash_node);
+ return do_complete;
}
-static void io_poll_remove_all(struct io_ring_ctx *ctx)
+static bool io_poll_remove_one(struct io_kiocb *req)
{
- struct io_kiocb *req;
+ bool do_complete;
- spin_lock_irq(&ctx->completion_lock);
- while (!list_empty(&ctx->cancel_list)) {
- req = list_first_entry(&ctx->cancel_list, struct io_kiocb,list);
- io_poll_remove_one(req);
+ io_poll_remove_double(req);
+
+ if (req->opcode == IORING_OP_POLL_ADD) {
+ do_complete = __io_poll_remove_one(req, &req->poll);
+ } else {
+ struct async_poll *apoll = req->apoll;
+
+ /* non-poll requests have submit ref still */
+ do_complete = __io_poll_remove_one(req, &apoll->poll);
+ if (do_complete) {
+ io_put_req(req);
+ kfree(apoll->double_poll);
+ kfree(apoll);
+ }
}
- spin_unlock_irq(&ctx->completion_lock);
+
+ if (do_complete) {
+ io_cqring_fill_event(req, -ECANCELED);
+ io_commit_cqring(req->ctx);
+ req_set_fail_links(req);
+ io_put_req_deferred(req, 1);
+ }
+
+ return do_complete;
}
/*
- * Find a running poll command that matches one specified in sqe->addr,
- * and remove it if found.
+ * Returns true if we found and killed one or more poll requests
*/
-static int io_poll_remove(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
+ struct files_struct *files)
{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_kiocb *poll_req, *next;
- int ret = -ENOENT;
+ struct hlist_node *tmp;
+ struct io_kiocb *req;
+ int posted = 0, i;
+ spin_lock_irq(&ctx->completion_lock);
+ for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
+ struct hlist_head *list;
+
+ list = &ctx->cancel_hash[i];
+ hlist_for_each_entry_safe(req, tmp, list, hash_node) {
+ if (io_match_task(req, tsk, files))
+ posted += io_poll_remove_one(req);
+ }
+ }
+ spin_unlock_irq(&ctx->completion_lock);
+
+ if (posted)
+ io_cqring_ev_posted(ctx);
+
+ return posted != 0;
+}
+
+static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr)
+{
+ struct hlist_head *list;
+ struct io_kiocb *req;
+
+ list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
+ hlist_for_each_entry(req, list, hash_node) {
+ if (sqe_addr != req->user_data)
+ continue;
+ if (io_poll_remove_one(req))
+ return 0;
+ return -EALREADY;
+ }
+
+ return -ENOENT;
+}
+
+static int io_poll_remove_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
sqe->poll_events)
return -EINVAL;
- spin_lock_irq(&ctx->completion_lock);
- list_for_each_entry_safe(poll_req, next, &ctx->cancel_list, list) {
- if (READ_ONCE(sqe->addr) == poll_req->user_data) {
- io_poll_remove_one(poll_req);
- ret = 0;
- break;
- }
- }
- spin_unlock_irq(&ctx->completion_lock);
-
- io_cqring_add_event(req->ctx, sqe->user_data, ret);
- io_put_req(req);
+ req->poll.addr = READ_ONCE(sqe->addr);
return 0;
}
-static void io_poll_complete(struct io_ring_ctx *ctx, struct io_kiocb *req,
- __poll_t mask)
+/*
+ * Find a running poll command that matches one specified in sqe->addr,
+ * and remove it if found.
+ */
+static int io_poll_remove(struct io_kiocb *req)
{
- req->poll.done = true;
- io_cqring_fill_event(ctx, req->user_data, mangle_poll(mask));
- io_commit_cqring(ctx);
-}
-
-static void io_poll_complete_work(struct work_struct *work)
-{
- struct io_kiocb *req = container_of(work, struct io_kiocb, work);
- struct io_poll_iocb *poll = &req->poll;
- struct poll_table_struct pt = { ._key = poll->events };
struct io_ring_ctx *ctx = req->ctx;
- const struct cred *old_cred;
- __poll_t mask = 0;
+ u64 addr;
+ int ret;
- old_cred = override_creds(ctx->creds);
-
- if (!READ_ONCE(poll->canceled))
- mask = vfs_poll(poll->file, &pt) & poll->events;
-
- /*
- * Note that ->ki_cancel callers also delete iocb from active_reqs after
- * calling ->ki_cancel. We need the ctx_lock roundtrip here to
- * synchronize with them. In the cancellation case the list_del_init
- * itself is not actually needed, but harmless so we keep it in to
- * avoid further branches in the fast path.
- */
+ addr = req->poll.addr;
spin_lock_irq(&ctx->completion_lock);
- if (!mask && !READ_ONCE(poll->canceled)) {
- add_wait_queue(poll->head, &poll->wait);
- spin_unlock_irq(&ctx->completion_lock);
- goto out;
- }
- list_del_init(&req->list);
- io_poll_complete(ctx, req, mask);
+ ret = io_poll_cancel(ctx, addr);
spin_unlock_irq(&ctx->completion_lock);
- io_cqring_ev_posted(ctx);
- io_put_req(req);
-out:
- revert_creds(old_cred);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+ return 0;
}
static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
void *key)
{
- struct io_poll_iocb *poll = container_of(wait, struct io_poll_iocb,
- wait);
- struct io_kiocb *req = container_of(poll, struct io_kiocb, poll);
- struct io_ring_ctx *ctx = req->ctx;
- __poll_t mask = key_to_poll(key);
- unsigned long flags;
+ struct io_kiocb *req = wait->private;
+ struct io_poll_iocb *poll = &req->poll;
- /* for instances that support it check for an event match first: */
- if (mask && !(mask & poll->events))
- return 0;
-
- list_del_init(&poll->wait.entry);
-
- if (mask && spin_trylock_irqsave(&ctx->completion_lock, flags)) {
- list_del(&req->list);
- io_poll_complete(ctx, req, mask);
- spin_unlock_irqrestore(&ctx->completion_lock, flags);
-
- io_cqring_ev_posted(ctx);
- io_put_req(req);
- } else {
- io_queue_async_work(ctx, req);
- }
-
- return 1;
+ return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
}
-struct io_poll_table {
- struct poll_table_struct pt;
- struct io_kiocb *req;
- int error;
-};
-
static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
struct poll_table_struct *p)
{
struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
- if (unlikely(pt->req->poll.head)) {
- pt->error = -EINVAL;
- return;
- }
-
- pt->error = 0;
- pt->req->poll.head = head;
- add_wait_queue(head, &pt->req->poll.wait);
+ __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
}
-static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_poll_iocb *poll = &req->poll;
- struct io_ring_ctx *ctx = req->ctx;
- struct io_poll_table ipt;
- bool cancel = false;
- __poll_t mask;
- u16 events;
+ u32 events;
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
return -EINVAL;
- if (!poll->file)
- return -EBADF;
- req->submit.sqe = NULL;
- INIT_WORK(&req->work, io_poll_complete_work);
- events = READ_ONCE(sqe->poll_events);
- poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP;
+ events = READ_ONCE(sqe->poll32_events);
+#ifdef __BIG_ENDIAN
+ events = swahw32(events);
+#endif
+ poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP |
+ (events & EPOLLEXCLUSIVE);
+ return 0;
+}
- poll->head = NULL;
- poll->done = false;
- poll->canceled = false;
+static int io_poll_add(struct io_kiocb *req)
+{
+ struct io_poll_iocb *poll = &req->poll;
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_poll_table ipt;
+ __poll_t mask;
ipt.pt._qproc = io_poll_queue_proc;
- ipt.pt._key = poll->events;
- ipt.req = req;
- ipt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */
- /* initialized the list so that we can do list_empty checks */
- INIT_LIST_HEAD(&poll->wait.entry);
- init_waitqueue_func_entry(&poll->wait, io_poll_wake);
+ mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
+ io_poll_wake);
- INIT_LIST_HEAD(&req->list);
-
- mask = vfs_poll(poll->file, &ipt.pt) & poll->events;
-
- spin_lock_irq(&ctx->completion_lock);
- if (likely(poll->head)) {
- spin_lock(&poll->head->lock);
- if (unlikely(list_empty(&poll->wait.entry))) {
- if (ipt.error)
- cancel = true;
- ipt.error = 0;
- mask = 0;
- }
- if (mask || ipt.error)
- list_del_init(&poll->wait.entry);
- else if (cancel)
- WRITE_ONCE(poll->canceled, true);
- else if (!poll->done) /* actually waiting for an event */
- list_add_tail(&req->list, &ctx->cancel_list);
- spin_unlock(&poll->head->lock);
- }
if (mask) { /* no async, we'd stolen it */
ipt.error = 0;
- io_poll_complete(ctx, req, mask);
+ io_poll_complete(req, mask, 0);
}
spin_unlock_irq(&ctx->completion_lock);
@@ -1961,201 +5512,615 @@
static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
{
- struct io_ring_ctx *ctx;
- struct io_kiocb *req, *prev;
+ struct io_timeout_data *data = container_of(timer,
+ struct io_timeout_data, timer);
+ struct io_kiocb *req = data->req;
+ struct io_ring_ctx *ctx = req->ctx;
unsigned long flags;
- req = container_of(timer, struct io_kiocb, timeout.timer);
- ctx = req->ctx;
- atomic_inc(&ctx->cq_timeouts);
-
spin_lock_irqsave(&ctx->completion_lock, flags);
- /*
- * Adjust the reqs sequence before the current one because it
- * will consume a slot in the cq_ring and the the cq_tail pointer
- * will be increased, otherwise other timeout reqs may return in
- * advance without waiting for enough wait_nr.
- */
- prev = req;
- list_for_each_entry_continue_reverse(prev, &ctx->timeout_list, list)
- prev->sequence++;
- list_del(&req->list);
+ list_del_init(&req->timeout.list);
+ atomic_set(&req->ctx->cq_timeouts,
+ atomic_read(&req->ctx->cq_timeouts) + 1);
- io_cqring_fill_event(ctx, req->user_data, -ETIME);
+ io_cqring_fill_event(req, -ETIME);
io_commit_cqring(ctx);
spin_unlock_irqrestore(&ctx->completion_lock, flags);
io_cqring_ev_posted(ctx);
-
+ req_set_fail_links(req);
io_put_req(req);
return HRTIMER_NORESTART;
}
-static int io_timeout(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+static int __io_timeout_cancel(struct io_kiocb *req)
{
- unsigned count;
+ struct io_timeout_data *io = req->async_data;
+ int ret;
+
+ ret = hrtimer_try_to_cancel(&io->timer);
+ if (ret == -1)
+ return -EALREADY;
+ list_del_init(&req->timeout.list);
+
+ req_set_fail_links(req);
+ io_cqring_fill_event(req, -ECANCELED);
+ io_put_req_deferred(req, 1);
+ return 0;
+}
+
+static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
+{
+ struct io_kiocb *req;
+ int ret = -ENOENT;
+
+ list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
+ if (user_data == req->user_data) {
+ ret = 0;
+ break;
+ }
+ }
+
+ if (ret == -ENOENT)
+ return ret;
+
+ return __io_timeout_cancel(req);
+}
+
+static int io_timeout_remove_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+ if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->timeout_flags ||
+ sqe->splice_fd_in)
+ return -EINVAL;
+
+ req->timeout_rem.addr = READ_ONCE(sqe->addr);
+ return 0;
+}
+
+/*
+ * Remove or update an existing timeout command
+ */
+static int io_timeout_remove(struct io_kiocb *req)
+{
struct io_ring_ctx *ctx = req->ctx;
- struct list_head *entry;
- struct timespec64 ts;
- unsigned span = 0;
+ int ret;
- if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+ spin_lock_irq(&ctx->completion_lock);
+ ret = io_timeout_cancel(ctx, req->timeout_rem.addr);
+
+ io_cqring_fill_event(req, ret);
+ io_commit_cqring(ctx);
+ spin_unlock_irq(&ctx->completion_lock);
+ io_cqring_ev_posted(ctx);
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_put_req(req);
+ return 0;
+}
+
+static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+ bool is_timeout_link)
+{
+ struct io_timeout_data *data;
+ unsigned flags;
+ u32 off = READ_ONCE(sqe->off);
+
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
- if (sqe->flags || sqe->ioprio || sqe->buf_index || sqe->timeout_flags ||
- sqe->len != 1)
+ if (sqe->ioprio || sqe->buf_index || sqe->len != 1 ||
+ sqe->splice_fd_in)
+ return -EINVAL;
+ if (off && is_timeout_link)
+ return -EINVAL;
+ flags = READ_ONCE(sqe->timeout_flags);
+ if (flags & ~IORING_TIMEOUT_ABS)
return -EINVAL;
- if (get_timespec64(&ts, u64_to_user_ptr(sqe->addr)))
+ req->timeout.off = off;
+
+ if (!req->async_data && io_alloc_async_data(req))
+ return -ENOMEM;
+
+ data = req->async_data;
+ data->req = req;
+
+ if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
return -EFAULT;
- req->flags |= REQ_F_TIMEOUT;
+ if (flags & IORING_TIMEOUT_ABS)
+ data->mode = HRTIMER_MODE_ABS;
+ else
+ data->mode = HRTIMER_MODE_REL;
+
+ hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
+ return 0;
+}
+
+static int io_timeout(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_timeout_data *data = req->async_data;
+ struct list_head *entry;
+ u32 tail, off = req->timeout.off;
+
+ spin_lock_irq(&ctx->completion_lock);
/*
* sqe->off holds how many events that need to occur for this
* timeout event to be satisfied. If it isn't set, then this is
* a pure timeout request, sequence isn't used.
*/
- count = READ_ONCE(sqe->off);
- if (!count) {
- req->flags |= REQ_F_TIMEOUT_NOSEQ;
- spin_lock_irq(&ctx->completion_lock);
+ if (io_is_timeout_noseq(req)) {
entry = ctx->timeout_list.prev;
goto add;
}
- req->sequence = ctx->cached_sq_head + count - 1;
- /* reuse it to store the count */
- req->submit.sequence = count;
+ tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
+ req->timeout.target_seq = tail + off;
+
+ /* Update the last seq here in case io_flush_timeouts() hasn't.
+ * This is safe because ->completion_lock is held, and submissions
+ * and completions are never mixed in the same ->completion_lock section.
+ */
+ ctx->cq_last_tm_flush = tail;
/*
* Insertion sort, ensuring the first entry in the list is always
* the one we need first.
*/
- spin_lock_irq(&ctx->completion_lock);
list_for_each_prev(entry, &ctx->timeout_list) {
- struct io_kiocb *nxt = list_entry(entry, struct io_kiocb, list);
- unsigned nxt_sq_head;
- long long tmp, tmp_nxt;
+ struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
+ timeout.list);
- if (nxt->flags & REQ_F_TIMEOUT_NOSEQ)
+ if (io_is_timeout_noseq(nxt))
continue;
-
- /*
- * Since cached_sq_head + count - 1 can overflow, use type long
- * long to store it.
- */
- tmp = (long long)ctx->cached_sq_head + count - 1;
- nxt_sq_head = nxt->sequence - nxt->submit.sequence + 1;
- tmp_nxt = (long long)nxt_sq_head + nxt->submit.sequence - 1;
-
- /*
- * cached_sq_head may overflow, and it will never overflow twice
- * once there is some timeout req still be valid.
- */
- if (ctx->cached_sq_head < nxt_sq_head)
- tmp += UINT_MAX;
-
- if (tmp > tmp_nxt)
+ /* nxt.seq is behind @tail, otherwise would've been completed */
+ if (off >= nxt->timeout.target_seq - tail)
break;
-
- /*
- * Sequence of reqs after the insert one and itself should
- * be adjusted because each timeout req consumes a slot.
- */
- span++;
- nxt->sequence++;
}
- req->sequence -= span;
add:
- list_add(&req->list, entry);
+ list_add(&req->timeout.list, entry);
+ data->timer.function = io_timeout_fn;
+ hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
spin_unlock_irq(&ctx->completion_lock);
-
- hrtimer_init(&req->timeout.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- req->timeout.timer.function = io_timeout_fn;
- hrtimer_start(&req->timeout.timer, timespec64_to_ktime(ts),
- HRTIMER_MODE_REL);
return 0;
}
-static int io_req_defer(struct io_ring_ctx *ctx, struct io_kiocb *req,
- struct sqe_submit *s)
+static bool io_cancel_cb(struct io_wq_work *work, void *data)
{
- struct io_uring_sqe *sqe_copy;
+ struct io_kiocb *req = container_of(work, struct io_kiocb, work);
- if (!io_sequence_defer(ctx, req) && list_empty(&ctx->defer_list))
- return 0;
+ return req->user_data == (unsigned long) data;
+}
- sqe_copy = kmalloc(sizeof(*sqe_copy), GFP_KERNEL);
- if (!sqe_copy)
- return -EAGAIN;
+static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr)
+{
+ enum io_wq_cancel cancel_ret;
+ int ret = 0;
- spin_lock_irq(&ctx->completion_lock);
- if (!io_sequence_defer(ctx, req) && list_empty(&ctx->defer_list)) {
- spin_unlock_irq(&ctx->completion_lock);
- kfree(sqe_copy);
- return 0;
+ cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr, false);
+ switch (cancel_ret) {
+ case IO_WQ_CANCEL_OK:
+ ret = 0;
+ break;
+ case IO_WQ_CANCEL_RUNNING:
+ ret = -EALREADY;
+ break;
+ case IO_WQ_CANCEL_NOTFOUND:
+ ret = -ENOENT;
+ break;
}
- memcpy(&req->submit, s, sizeof(*s));
- memcpy(sqe_copy, s->sqe, sizeof(*sqe_copy));
- req->submit.sqe = sqe_copy;
+ return ret;
+}
- INIT_WORK(&req->work, io_sq_wq_submit_work);
- list_add_tail(&req->list, &ctx->defer_list);
+static void io_async_find_and_cancel(struct io_ring_ctx *ctx,
+ struct io_kiocb *req, __u64 sqe_addr,
+ int success_ret)
+{
+ unsigned long flags;
+ int ret;
+
+ ret = io_async_cancel_one(ctx, (void *) (unsigned long) sqe_addr);
+ if (ret != -ENOENT) {
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+ goto done;
+ }
+
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+ ret = io_timeout_cancel(ctx, sqe_addr);
+ if (ret != -ENOENT)
+ goto done;
+ ret = io_poll_cancel(ctx, sqe_addr);
+done:
+ if (!ret)
+ ret = success_ret;
+ io_cqring_fill_event(req, ret);
+ io_commit_cqring(ctx);
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+ io_cqring_ev_posted(ctx);
+
+ if (ret < 0)
+ req_set_fail_links(req);
+ io_put_req(req);
+}
+
+static int io_async_cancel_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+ if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags ||
+ sqe->splice_fd_in)
+ return -EINVAL;
+
+ req->cancel.addr = READ_ONCE(sqe->addr);
+ return 0;
+}
+
+static int io_async_cancel(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+
+ io_async_find_and_cancel(ctx, req, req->cancel.addr, 0);
+ return 0;
+}
+
+static int io_files_update_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ if (unlikely(req->ctx->flags & IORING_SETUP_SQPOLL))
+ return -EINVAL;
+ if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+ return -EINVAL;
+ if (sqe->ioprio || sqe->rw_flags)
+ return -EINVAL;
+
+ req->files_update.offset = READ_ONCE(sqe->off);
+ req->files_update.nr_args = READ_ONCE(sqe->len);
+ if (!req->files_update.nr_args)
+ return -EINVAL;
+ req->files_update.arg = READ_ONCE(sqe->addr);
+ return 0;
+}
+
+static int io_files_update(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_uring_files_update up;
+ int ret;
+
+ if (force_nonblock)
+ return -EAGAIN;
+
+ up.offset = req->files_update.offset;
+ up.fds = req->files_update.arg;
+
+ mutex_lock(&ctx->uring_lock);
+ ret = __io_sqe_files_update(ctx, &up, req->files_update.nr_args);
+ mutex_unlock(&ctx->uring_lock);
+
+ if (ret < 0)
+ req_set_fail_links(req);
+ __io_req_complete(req, ret, 0, cs);
+ return 0;
+}
+
+static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ switch (req->opcode) {
+ case IORING_OP_NOP:
+ return 0;
+ case IORING_OP_READV:
+ case IORING_OP_READ_FIXED:
+ case IORING_OP_READ:
+ return io_read_prep(req, sqe);
+ case IORING_OP_WRITEV:
+ case IORING_OP_WRITE_FIXED:
+ case IORING_OP_WRITE:
+ return io_write_prep(req, sqe);
+ case IORING_OP_POLL_ADD:
+ return io_poll_add_prep(req, sqe);
+ case IORING_OP_POLL_REMOVE:
+ return io_poll_remove_prep(req, sqe);
+ case IORING_OP_FSYNC:
+ return io_prep_fsync(req, sqe);
+ case IORING_OP_SYNC_FILE_RANGE:
+ return io_prep_sfr(req, sqe);
+ case IORING_OP_SENDMSG:
+ case IORING_OP_SEND:
+ return io_sendmsg_prep(req, sqe);
+ case IORING_OP_RECVMSG:
+ case IORING_OP_RECV:
+ return io_recvmsg_prep(req, sqe);
+ case IORING_OP_CONNECT:
+ return io_connect_prep(req, sqe);
+ case IORING_OP_TIMEOUT:
+ return io_timeout_prep(req, sqe, false);
+ case IORING_OP_TIMEOUT_REMOVE:
+ return io_timeout_remove_prep(req, sqe);
+ case IORING_OP_ASYNC_CANCEL:
+ return io_async_cancel_prep(req, sqe);
+ case IORING_OP_LINK_TIMEOUT:
+ return io_timeout_prep(req, sqe, true);
+ case IORING_OP_ACCEPT:
+ return io_accept_prep(req, sqe);
+ case IORING_OP_FALLOCATE:
+ return io_fallocate_prep(req, sqe);
+ case IORING_OP_OPENAT:
+ return io_openat_prep(req, sqe);
+ case IORING_OP_CLOSE:
+ return io_close_prep(req, sqe);
+ case IORING_OP_FILES_UPDATE:
+ return io_files_update_prep(req, sqe);
+ case IORING_OP_STATX:
+ return io_statx_prep(req, sqe);
+ case IORING_OP_FADVISE:
+ return io_fadvise_prep(req, sqe);
+ case IORING_OP_MADVISE:
+ return io_madvise_prep(req, sqe);
+ case IORING_OP_OPENAT2:
+ return io_openat2_prep(req, sqe);
+ case IORING_OP_EPOLL_CTL:
+ return io_epoll_ctl_prep(req, sqe);
+ case IORING_OP_SPLICE:
+ return io_splice_prep(req, sqe);
+ case IORING_OP_PROVIDE_BUFFERS:
+ return io_provide_buffers_prep(req, sqe);
+ case IORING_OP_REMOVE_BUFFERS:
+ return io_remove_buffers_prep(req, sqe);
+ case IORING_OP_TEE:
+ return io_tee_prep(req, sqe);
+ }
+
+ printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
+ req->opcode);
+ return-EINVAL;
+}
+
+static int io_req_defer_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ if (!sqe)
+ return 0;
+ if (io_alloc_async_data(req))
+ return -EAGAIN;
+ return io_req_prep(req, sqe);
+}
+
+static u32 io_get_sequence(struct io_kiocb *req)
+{
+ struct io_kiocb *pos;
+ struct io_ring_ctx *ctx = req->ctx;
+ u32 total_submitted, nr_reqs = 1;
+
+ if (req->flags & REQ_F_LINK_HEAD)
+ list_for_each_entry(pos, &req->link_list, link_list)
+ nr_reqs++;
+
+ total_submitted = ctx->cached_sq_head - ctx->cached_sq_dropped;
+ return total_submitted - nr_reqs;
+}
+
+static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_defer_entry *de;
+ int ret;
+ u32 seq;
+
+ /* Still need defer if there is pending req in defer list. */
+ if (likely(list_empty_careful(&ctx->defer_list) &&
+ !(req->flags & REQ_F_IO_DRAIN)))
+ return 0;
+
+ seq = io_get_sequence(req);
+ /* Still a chance to pass the sequence check */
+ if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
+ return 0;
+
+ if (!req->async_data) {
+ ret = io_req_defer_prep(req, sqe);
+ if (ret)
+ return ret;
+ }
+ io_prep_async_link(req);
+ de = kmalloc(sizeof(*de), GFP_KERNEL);
+ if (!de)
+ return -ENOMEM;
+
+ spin_lock_irq(&ctx->completion_lock);
+ if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
+ spin_unlock_irq(&ctx->completion_lock);
+ kfree(de);
+ io_queue_async_work(req);
+ return -EIOCBQUEUED;
+ }
+
+ trace_io_uring_defer(ctx, req, req->user_data);
+ de->req = req;
+ de->seq = seq;
+ list_add_tail(&de->list, &ctx->defer_list);
spin_unlock_irq(&ctx->completion_lock);
return -EIOCBQUEUED;
}
-static int __io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
- const struct sqe_submit *s, bool force_nonblock)
+static void io_req_drop_files(struct io_kiocb *req)
{
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_uring_task *tctx = req->task->io_uring;
+ unsigned long flags;
+
+ if (req->work.flags & IO_WQ_WORK_FILES) {
+ put_files_struct(req->work.identity->files);
+ put_nsproxy(req->work.identity->nsproxy);
+ }
+ spin_lock_irqsave(&ctx->inflight_lock, flags);
+ list_del(&req->inflight_entry);
+ spin_unlock_irqrestore(&ctx->inflight_lock, flags);
+ req->flags &= ~REQ_F_INFLIGHT;
+ req->work.flags &= ~IO_WQ_WORK_FILES;
+ if (atomic_read(&tctx->in_idle))
+ wake_up(&tctx->wait);
+}
+
+static void __io_clean_op(struct io_kiocb *req)
+{
+ if (req->flags & REQ_F_BUFFER_SELECTED) {
+ switch (req->opcode) {
+ case IORING_OP_READV:
+ case IORING_OP_READ_FIXED:
+ case IORING_OP_READ:
+ kfree((void *)(unsigned long)req->rw.addr);
+ break;
+ case IORING_OP_RECVMSG:
+ case IORING_OP_RECV:
+ kfree(req->sr_msg.kbuf);
+ break;
+ }
+ req->flags &= ~REQ_F_BUFFER_SELECTED;
+ }
+
+ if (req->flags & REQ_F_NEED_CLEANUP) {
+ switch (req->opcode) {
+ case IORING_OP_READV:
+ case IORING_OP_READ_FIXED:
+ case IORING_OP_READ:
+ case IORING_OP_WRITEV:
+ case IORING_OP_WRITE_FIXED:
+ case IORING_OP_WRITE: {
+ struct io_async_rw *io = req->async_data;
+ if (io->free_iovec)
+ kfree(io->free_iovec);
+ break;
+ }
+ case IORING_OP_RECVMSG:
+ case IORING_OP_SENDMSG: {
+ struct io_async_msghdr *io = req->async_data;
+ if (io->iov != io->fast_iov)
+ kfree(io->iov);
+ break;
+ }
+ case IORING_OP_SPLICE:
+ case IORING_OP_TEE:
+ io_put_file(req, req->splice.file_in,
+ (req->splice.flags & SPLICE_F_FD_IN_FIXED));
+ break;
+ case IORING_OP_OPENAT:
+ case IORING_OP_OPENAT2:
+ if (req->open.filename)
+ putname(req->open.filename);
+ break;
+ }
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ }
+}
+
+static int io_issue_sqe(struct io_kiocb *req, bool force_nonblock,
+ struct io_comp_state *cs)
+{
+ struct io_ring_ctx *ctx = req->ctx;
int ret;
- req->user_data = READ_ONCE(s->sqe->user_data);
-
- if (unlikely(s->index >= ctx->sq_entries))
- return -EINVAL;
-
- switch (req->submit.opcode) {
+ switch (req->opcode) {
case IORING_OP_NOP:
- ret = io_nop(req, req->user_data);
+ ret = io_nop(req, cs);
break;
case IORING_OP_READV:
- if (unlikely(s->sqe->buf_index))
- return -EINVAL;
- ret = io_read(req, s, force_nonblock);
+ case IORING_OP_READ_FIXED:
+ case IORING_OP_READ:
+ ret = io_read(req, force_nonblock, cs);
break;
case IORING_OP_WRITEV:
- if (unlikely(s->sqe->buf_index))
- return -EINVAL;
- ret = io_write(req, s, force_nonblock);
- break;
- case IORING_OP_READ_FIXED:
- ret = io_read(req, s, force_nonblock);
- break;
case IORING_OP_WRITE_FIXED:
- ret = io_write(req, s, force_nonblock);
+ case IORING_OP_WRITE:
+ ret = io_write(req, force_nonblock, cs);
break;
case IORING_OP_FSYNC:
- ret = io_fsync(req, s->sqe, force_nonblock);
+ ret = io_fsync(req, force_nonblock);
break;
case IORING_OP_POLL_ADD:
- ret = io_poll_add(req, s->sqe);
+ ret = io_poll_add(req);
break;
case IORING_OP_POLL_REMOVE:
- ret = io_poll_remove(req, s->sqe);
+ ret = io_poll_remove(req);
break;
case IORING_OP_SYNC_FILE_RANGE:
- ret = io_sync_file_range(req, s->sqe, force_nonblock);
+ ret = io_sync_file_range(req, force_nonblock);
break;
case IORING_OP_SENDMSG:
- ret = io_sendmsg(req, s->sqe, force_nonblock);
+ ret = io_sendmsg(req, force_nonblock, cs);
+ break;
+ case IORING_OP_SEND:
+ ret = io_send(req, force_nonblock, cs);
break;
case IORING_OP_RECVMSG:
- ret = io_recvmsg(req, s->sqe, force_nonblock);
+ ret = io_recvmsg(req, force_nonblock, cs);
+ break;
+ case IORING_OP_RECV:
+ ret = io_recv(req, force_nonblock, cs);
break;
case IORING_OP_TIMEOUT:
- ret = io_timeout(req, s->sqe);
+ ret = io_timeout(req);
+ break;
+ case IORING_OP_TIMEOUT_REMOVE:
+ ret = io_timeout_remove(req);
+ break;
+ case IORING_OP_ACCEPT:
+ ret = io_accept(req, force_nonblock, cs);
+ break;
+ case IORING_OP_CONNECT:
+ ret = io_connect(req, force_nonblock, cs);
+ break;
+ case IORING_OP_ASYNC_CANCEL:
+ ret = io_async_cancel(req);
+ break;
+ case IORING_OP_FALLOCATE:
+ ret = io_fallocate(req, force_nonblock);
+ break;
+ case IORING_OP_OPENAT:
+ ret = io_openat(req, force_nonblock);
+ break;
+ case IORING_OP_CLOSE:
+ ret = io_close(req, force_nonblock, cs);
+ break;
+ case IORING_OP_FILES_UPDATE:
+ ret = io_files_update(req, force_nonblock, cs);
+ break;
+ case IORING_OP_STATX:
+ ret = io_statx(req, force_nonblock);
+ break;
+ case IORING_OP_FADVISE:
+ ret = io_fadvise(req, force_nonblock);
+ break;
+ case IORING_OP_MADVISE:
+ ret = io_madvise(req, force_nonblock);
+ break;
+ case IORING_OP_OPENAT2:
+ ret = io_openat2(req, force_nonblock);
+ break;
+ case IORING_OP_EPOLL_CTL:
+ ret = io_epoll_ctl(req, force_nonblock, cs);
+ break;
+ case IORING_OP_SPLICE:
+ ret = io_splice(req, force_nonblock);
+ break;
+ case IORING_OP_PROVIDE_BUFFERS:
+ ret = io_provide_buffers(req, force_nonblock, cs);
+ break;
+ case IORING_OP_REMOVE_BUFFERS:
+ ret = io_remove_buffers(req, force_nonblock, cs);
+ break;
+ case IORING_OP_TEE:
+ ret = io_tee(req, force_nonblock);
break;
default:
ret = -EINVAL;
@@ -2165,451 +6130,325 @@
if (ret)
return ret;
- if (ctx->flags & IORING_SETUP_IOPOLL) {
- if (req->result == -EAGAIN)
- return -EAGAIN;
+ /* If the op doesn't have a file, we're not polling for it */
+ if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file) {
+ const bool in_async = io_wq_current_is_worker();
/* workqueue context doesn't hold uring_lock, grab it now */
- if (s->needs_lock)
+ if (in_async)
mutex_lock(&ctx->uring_lock);
+
io_iopoll_req_issued(req);
- if (s->needs_lock)
+
+ if (in_async)
mutex_unlock(&ctx->uring_lock);
}
return 0;
}
-static struct async_list *io_async_list_from_req(struct io_ring_ctx *ctx,
- struct io_kiocb *req)
-{
- switch (req->submit.opcode) {
- case IORING_OP_READV:
- case IORING_OP_READ_FIXED:
- return &ctx->pending_async[READ];
- case IORING_OP_WRITEV:
- case IORING_OP_WRITE_FIXED:
- return &ctx->pending_async[WRITE];
- default:
- return NULL;
- }
-}
-
-static inline bool io_req_needs_user(struct io_kiocb *req)
-{
- return !(req->submit.opcode == IORING_OP_READ_FIXED ||
- req->submit.opcode == IORING_OP_WRITE_FIXED);
-}
-
-static void io_sq_wq_submit_work(struct work_struct *work)
+static struct io_wq_work *io_wq_submit_work(struct io_wq_work *work)
{
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
- struct fs_struct *old_fs_struct = current->fs;
- struct io_ring_ctx *ctx = req->ctx;
- struct mm_struct *cur_mm = NULL;
- struct async_list *async_list;
- const struct cred *old_cred;
- LIST_HEAD(req_list);
- mm_segment_t old_fs;
- int ret;
+ struct io_kiocb *timeout;
+ int ret = 0;
- old_cred = override_creds(ctx->creds);
- async_list = io_async_list_from_req(ctx, req);
+ timeout = io_prep_linked_timeout(req);
+ if (timeout)
+ io_queue_linked_timeout(timeout);
- allow_kernel_signal(SIGINT);
-restart:
- do {
- struct sqe_submit *s = &req->submit;
- const struct io_uring_sqe *sqe = s->sqe;
- unsigned int flags = req->flags;
+ /* if NO_CANCEL is set, we must still run the work */
+ if ((work->flags & (IO_WQ_WORK_CANCEL|IO_WQ_WORK_NO_CANCEL)) ==
+ IO_WQ_WORK_CANCEL) {
+ ret = -ECANCELED;
+ }
- /* Ensure we clear previously set non-block flag */
- req->rw.ki_flags &= ~IOCB_NOWAIT;
-
- if ((req->fs && req->fs != current->fs) ||
- (!req->fs && current->fs != old_fs_struct)) {
- task_lock(current);
- if (req->fs)
- current->fs = req->fs;
- else
- current->fs = old_fs_struct;
- task_unlock(current);
- }
-
- ret = 0;
- if (io_req_needs_user(req) && !cur_mm) {
- if (!mmget_not_zero(ctx->sqo_mm)) {
- ret = -EFAULT;
- goto end_req;
- } else {
- cur_mm = ctx->sqo_mm;
- use_mm(cur_mm);
- old_fs = get_fs();
- set_fs(USER_DS);
- }
- }
-
- if (!ret) {
- req->work_task = current;
-
+ if (!ret) {
+ do {
+ ret = io_issue_sqe(req, false, NULL);
/*
- * Pairs with the smp_store_mb() (B) in
- * io_cancel_async_work().
+ * We can get EAGAIN for polled IO even though we're
+ * forcing a sync submission from here, since we can't
+ * wait for request slots on the block side.
*/
- smp_mb(); /* A */
- if (req->flags & REQ_F_CANCEL) {
- ret = -ECANCELED;
- goto end_req;
- }
-
- s->has_user = cur_mm != NULL;
- s->needs_lock = true;
- do {
- ret = __io_submit_sqe(ctx, req, s, false);
- /*
- * We can get EAGAIN for polled IO even though
- * we're forcing a sync submission from here,
- * since we can't wait for request slots on the
- * block side.
- */
- if (ret != -EAGAIN)
- break;
- cond_resched();
- } while (1);
- }
-end_req:
- spin_lock_irq(&ctx->task_lock);
- list_del_init(&req->task_list);
- spin_unlock_irq(&ctx->task_lock);
-
- /* drop submission reference */
- io_put_req(req);
-
- if (ret) {
- io_cqring_add_event(ctx, sqe->user_data, ret);
- io_put_req(req);
- }
-
- /* async context always use a copy of the sqe */
- kfree(sqe);
-
- /* req from defer and link list needn't decrease async cnt */
- if (flags & (REQ_F_IO_DRAINED | REQ_F_LINK_DONE))
- goto out;
-
- if (!async_list)
- break;
- if (!list_empty(&req_list)) {
- req = list_first_entry(&req_list, struct io_kiocb,
- list);
- list_del(&req->list);
- continue;
- }
- if (list_empty(&async_list->list))
- break;
-
- req = NULL;
- spin_lock(&async_list->lock);
- if (list_empty(&async_list->list)) {
- spin_unlock(&async_list->lock);
- break;
- }
- list_splice_init(&async_list->list, &req_list);
- spin_unlock(&async_list->lock);
-
- req = list_first_entry(&req_list, struct io_kiocb, list);
- list_del(&req->list);
- } while (req);
-
- /*
- * Rare case of racing with a submitter. If we find the count has
- * dropped to zero AND we have pending work items, then restart
- * the processing. This is a tiny race window.
- */
- if (async_list) {
- ret = atomic_dec_return(&async_list->cnt);
- while (!ret && !list_empty(&async_list->list)) {
- spin_lock(&async_list->lock);
- atomic_inc(&async_list->cnt);
- list_splice_init(&async_list->list, &req_list);
- spin_unlock(&async_list->lock);
-
- if (!list_empty(&req_list)) {
- req = list_first_entry(&req_list,
- struct io_kiocb, list);
- list_del(&req->list);
- goto restart;
- }
- ret = atomic_dec_return(&async_list->cnt);
- }
- }
-
-out:
- disallow_signal(SIGINT);
- if (cur_mm) {
- set_fs(old_fs);
- unuse_mm(cur_mm);
- mmput(cur_mm);
- }
- revert_creds(old_cred);
- if (old_fs_struct != current->fs) {
- task_lock(current);
- current->fs = old_fs_struct;
- task_unlock(current);
- }
-}
-
-/*
- * See if we can piggy back onto previously submitted work, that is still
- * running. We currently only allow this if the new request is sequential
- * to the previous one we punted.
- */
-static bool io_add_to_prev_work(struct async_list *list, struct io_kiocb *req)
-{
- bool ret;
-
- if (!list)
- return false;
- if (!(req->flags & REQ_F_SEQ_PREV))
- return false;
- if (!atomic_read(&list->cnt))
- return false;
-
- ret = true;
- spin_lock(&list->lock);
- list_add_tail(&req->list, &list->list);
- /*
- * Ensure we see a simultaneous modification from io_sq_wq_submit_work()
- */
- smp_mb();
- if (!atomic_read(&list->cnt)) {
- list_del_init(&req->list);
- ret = false;
+ if (ret != -EAGAIN)
+ break;
+ cond_resched();
+ } while (1);
}
if (ret) {
- struct io_ring_ctx *ctx = req->ctx;
+ struct io_ring_ctx *lock_ctx = NULL;
- req->files = current->files;
+ if (req->ctx->flags & IORING_SETUP_IOPOLL)
+ lock_ctx = req->ctx;
- spin_lock_irq(&ctx->task_lock);
- list_add(&req->task_list, &ctx->task_list);
- req->work_task = NULL;
- spin_unlock_irq(&ctx->task_lock);
+ /*
+ * io_iopoll_complete() does not hold completion_lock to
+ * complete polled io, so here for polled io, we can not call
+ * io_req_complete() directly, otherwise there maybe concurrent
+ * access to cqring, defer_list, etc, which is not safe. Given
+ * that io_iopoll_complete() is always called under uring_lock,
+ * so here for polled io, we also get uring_lock to complete
+ * it.
+ */
+ if (lock_ctx)
+ mutex_lock(&lock_ctx->uring_lock);
+
+ req_set_fail_links(req);
+ io_req_complete(req, ret);
+
+ if (lock_ctx)
+ mutex_unlock(&lock_ctx->uring_lock);
}
- spin_unlock(&list->lock);
- return ret;
+
+ return io_steal_work(req);
}
-static bool io_op_needs_file(struct io_kiocb *req)
+static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
+ int index)
{
- switch (req->submit.opcode) {
- case IORING_OP_NOP:
- case IORING_OP_POLL_REMOVE:
- case IORING_OP_TIMEOUT:
- return false;
- default:
- return true;
- }
+ struct fixed_file_table *table;
+
+ table = &ctx->file_data->table[index >> IORING_FILE_TABLE_SHIFT];
+ return table->files[index & IORING_FILE_TABLE_MASK];
}
-static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s,
- struct io_submit_state *state, struct io_kiocb *req)
+static struct file *io_file_get(struct io_submit_state *state,
+ struct io_kiocb *req, int fd, bool fixed)
{
- unsigned flags;
- int fd;
+ struct io_ring_ctx *ctx = req->ctx;
+ struct file *file;
- flags = READ_ONCE(s->sqe->flags);
- fd = READ_ONCE(s->sqe->fd);
-
- if (flags & IOSQE_IO_DRAIN)
- req->flags |= REQ_F_IO_DRAIN;
- /*
- * All io need record the previous position, if LINK vs DARIN,
- * it can be used to mark the position of the first IO in the
- * link list.
- */
- req->sequence = s->sequence;
-
- if (!io_op_needs_file(req))
- return 0;
-
- if (flags & IOSQE_FIXED_FILE) {
- if (unlikely(!ctx->user_files ||
- (unsigned) fd >= ctx->nr_user_files))
- return -EBADF;
- req->file = ctx->user_files[fd];
- req->flags |= REQ_F_FIXED_FILE;
+ if (fixed) {
+ if (unlikely((unsigned int)fd >= ctx->nr_user_files))
+ return NULL;
+ fd = array_index_nospec(fd, ctx->nr_user_files);
+ file = io_file_from_index(ctx, fd);
+ if (file) {
+ req->fixed_file_refs = &ctx->file_data->node->refs;
+ percpu_ref_get(req->fixed_file_refs);
+ }
} else {
- if (s->needs_fixed_file)
- return -EBADF;
- req->file = io_file_get(state, fd);
- if (unlikely(!req->file))
- return -EBADF;
+ trace_io_uring_file_get(ctx, fd);
+ file = __io_file_get(state, fd);
}
- return 0;
+ if (file && file->f_op == &io_uring_fops &&
+ !(req->flags & REQ_F_INFLIGHT)) {
+ io_req_init_async(req);
+ req->flags |= REQ_F_INFLIGHT;
+
+ spin_lock_irq(&ctx->inflight_lock);
+ list_add(&req->inflight_entry, &ctx->inflight_list);
+ spin_unlock_irq(&ctx->inflight_lock);
+ }
+
+ return file;
}
-static int __io_queue_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
- struct sqe_submit *s)
+static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,
+ int fd)
{
+ bool fixed;
+
+ fixed = (req->flags & REQ_F_FIXED_FILE) != 0;
+ if (unlikely(!fixed && io_async_submit(req->ctx)))
+ return -EBADF;
+
+ req->file = io_file_get(state, req, fd, fixed);
+ if (req->file || io_op_defs[req->opcode].needs_file_no_error)
+ return 0;
+ return -EBADF;
+}
+
+static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
+{
+ struct io_timeout_data *data = container_of(timer,
+ struct io_timeout_data, timer);
+ struct io_kiocb *req = data->req;
+ struct io_ring_ctx *ctx = req->ctx;
+ struct io_kiocb *prev = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+
+ /*
+ * We don't expect the list to be empty, that will only happen if we
+ * race with the completion of the linked work.
+ */
+ if (!list_empty(&req->link_list)) {
+ prev = list_entry(req->link_list.prev, struct io_kiocb,
+ link_list);
+ if (refcount_inc_not_zero(&prev->refs))
+ list_del_init(&req->link_list);
+ else
+ prev = NULL;
+ }
+
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+
+ if (prev) {
+ io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
+ io_put_req_deferred(prev, 1);
+ } else {
+ io_cqring_add_event(req, -ETIME, 0);
+ io_put_req_deferred(req, 1);
+ }
+ return HRTIMER_NORESTART;
+}
+
+static void __io_queue_linked_timeout(struct io_kiocb *req)
+{
+ /*
+ * If the list is now empty, then our linked request finished before
+ * we got a chance to setup the timer
+ */
+ if (!list_empty(&req->link_list)) {
+ struct io_timeout_data *data = req->async_data;
+
+ data->timer.function = io_link_timeout_fn;
+ hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
+ data->mode);
+ }
+}
+
+static void io_queue_linked_timeout(struct io_kiocb *req)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+
+ spin_lock_irq(&ctx->completion_lock);
+ __io_queue_linked_timeout(req);
+ spin_unlock_irq(&ctx->completion_lock);
+
+ /* drop submission reference */
+ io_put_req(req);
+}
+
+static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
+{
+ struct io_kiocb *nxt;
+
+ if (!(req->flags & REQ_F_LINK_HEAD))
+ return NULL;
+ if (req->flags & REQ_F_LINK_TIMEOUT)
+ return NULL;
+
+ nxt = list_first_entry_or_null(&req->link_list, struct io_kiocb,
+ link_list);
+ if (!nxt || nxt->opcode != IORING_OP_LINK_TIMEOUT)
+ return NULL;
+
+ nxt->flags |= REQ_F_LTIMEOUT_ACTIVE;
+ req->flags |= REQ_F_LINK_TIMEOUT;
+ return nxt;
+}
+
+static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs)
+{
+ struct io_kiocb *linked_timeout;
+ const struct cred *old_creds = NULL;
int ret;
- ret = __io_submit_sqe(ctx, req, s, true);
+again:
+ linked_timeout = io_prep_linked_timeout(req);
+
+ if ((req->flags & REQ_F_WORK_INITIALIZED) &&
+ (req->work.flags & IO_WQ_WORK_CREDS) &&
+ req->work.identity->creds != current_cred()) {
+ if (old_creds)
+ revert_creds(old_creds);
+ if (old_creds == req->work.identity->creds)
+ old_creds = NULL; /* restored original creds */
+ else
+ old_creds = override_creds(req->work.identity->creds);
+ }
+
+ ret = io_issue_sqe(req, true, cs);
/*
* We async punt it if the file wasn't marked NOWAIT, or if the file
* doesn't support non-blocking read/write attempts
*/
- if (ret == -EAGAIN && (!(req->flags & REQ_F_NOWAIT) ||
- (req->flags & REQ_F_MUST_PUNT))) {
- struct io_uring_sqe *sqe_copy;
-
- sqe_copy = kmemdup(s->sqe, sizeof(*sqe_copy), GFP_KERNEL);
- if (sqe_copy) {
- struct async_list *list;
-
- s->sqe = sqe_copy;
- memcpy(&req->submit, s, sizeof(*s));
- list = io_async_list_from_req(ctx, req);
- if (!io_add_to_prev_work(list, req)) {
- if (list)
- atomic_inc(&list->cnt);
- INIT_WORK(&req->work, io_sq_wq_submit_work);
- io_queue_async_work(ctx, req);
- }
-
+ if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
+ if (!io_arm_poll_handler(req)) {
/*
* Queued up for async execution, worker will release
* submit reference when the iocb is actually submitted.
*/
- return 0;
+ io_queue_async_work(req);
}
- }
- /* drop submission reference */
- io_put_req(req);
+ if (linked_timeout)
+ io_queue_linked_timeout(linked_timeout);
+ } else if (likely(!ret)) {
+ /* drop submission reference */
+ req = io_put_req_find_next(req);
+ if (linked_timeout)
+ io_queue_linked_timeout(linked_timeout);
- /* and drop final reference, if we failed */
- if (ret) {
- io_cqring_add_event(ctx, req->user_data, ret);
- if (req->flags & REQ_F_LINK)
- req->flags |= REQ_F_FAIL_LINK;
- io_put_req(req);
- }
-
- return ret;
-}
-
-static int io_queue_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
- struct sqe_submit *s)
-{
- int ret;
-
- ret = io_req_defer(ctx, req, s);
- if (ret) {
- if (ret != -EIOCBQUEUED) {
- io_free_req(req);
- io_cqring_add_event(ctx, s->sqe->user_data, ret);
- }
- return 0;
- }
-
- return __io_queue_sqe(ctx, req, s);
-}
-
-static int io_queue_link_head(struct io_ring_ctx *ctx, struct io_kiocb *req,
- struct sqe_submit *s, struct io_kiocb *shadow)
-{
- int ret;
- int need_submit = false;
-
- if (!shadow)
- return io_queue_sqe(ctx, req, s);
-
- /*
- * Mark the first IO in link list as DRAIN, let all the following
- * IOs enter the defer list. all IO needs to be completed before link
- * list.
- */
- req->flags |= REQ_F_IO_DRAIN;
- ret = io_req_defer(ctx, req, s);
- if (ret) {
- if (ret != -EIOCBQUEUED) {
- io_free_req(req);
- __io_free_req(shadow);
- io_cqring_add_event(ctx, s->sqe->user_data, ret);
- return 0;
+ if (req) {
+ if (!(req->flags & REQ_F_FORCE_ASYNC))
+ goto again;
+ io_queue_async_work(req);
}
} else {
- /*
- * If ret == 0 means that all IOs in front of link io are
- * running done. let's queue link head.
- */
- need_submit = true;
+ /* un-prep timeout, so it'll be killed as any other linked */
+ req->flags &= ~REQ_F_LINK_TIMEOUT;
+ req_set_fail_links(req);
+ io_put_req(req);
+ io_req_complete(req, ret);
}
- /* Insert shadow req to defer_list, blocking next IOs */
- spin_lock_irq(&ctx->completion_lock);
- list_add_tail(&shadow->list, &ctx->defer_list);
- spin_unlock_irq(&ctx->completion_lock);
-
- if (need_submit)
- return __io_queue_sqe(ctx, req, s);
-
- return 0;
+ if (old_creds)
+ revert_creds(old_creds);
}
-#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK)
-
-static void io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s,
- struct io_submit_state *state, struct io_kiocb **link)
+static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+ struct io_comp_state *cs)
{
- struct io_uring_sqe *sqe_copy;
- struct io_kiocb *req;
int ret;
- /* enforce forwards compatibility on users */
- if (unlikely(s->sqe->flags & ~SQE_VALID_FLAGS)) {
- ret = -EINVAL;
- goto err;
- }
-
- req = io_get_req(ctx, state);
- if (unlikely(!req)) {
- ret = -EAGAIN;
- goto err;
- }
-
- memcpy(&req->submit, s, sizeof(*s));
- ret = io_req_set_file(ctx, s, state, req);
- if (unlikely(ret)) {
-err_req:
- io_free_req(req);
-err:
- io_cqring_add_event(ctx, s->sqe->user_data, ret);
- return;
- }
-
- req->user_data = s->sqe->user_data;
-
-#if defined(CONFIG_NET)
- switch (req->submit.opcode) {
- case IORING_OP_SENDMSG:
- case IORING_OP_RECVMSG:
- spin_lock(¤t->fs->lock);
- if (!current->fs->in_exec) {
- req->fs = current->fs;
- req->fs->users++;
+ ret = io_req_defer(req, sqe);
+ if (ret) {
+ if (ret != -EIOCBQUEUED) {
+fail_req:
+ req_set_fail_links(req);
+ io_put_req(req);
+ io_req_complete(req, ret);
}
- spin_unlock(¤t->fs->lock);
- if (!req->fs) {
- ret = -EAGAIN;
- goto err_req;
+ } else if (req->flags & REQ_F_FORCE_ASYNC) {
+ if (!req->async_data) {
+ ret = io_req_defer_prep(req, sqe);
+ if (unlikely(ret))
+ goto fail_req;
}
+ io_queue_async_work(req);
+ } else {
+ if (sqe) {
+ ret = io_req_prep(req, sqe);
+ if (unlikely(ret))
+ goto fail_req;
+ }
+ __io_queue_sqe(req, cs);
}
-#endif
+}
+
+static inline void io_queue_link_head(struct io_kiocb *req,
+ struct io_comp_state *cs)
+{
+ if (unlikely(req->flags & REQ_F_FAIL_LINK)) {
+ io_put_req(req);
+ io_req_complete(req, -ECANCELED);
+ } else
+ io_queue_sqe(req, NULL, cs);
+}
+
+static int io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+ struct io_kiocb **link, struct io_comp_state *cs)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ int ret;
/*
* If we already have a head request, queue this one for async
@@ -2619,26 +6458,52 @@
* conditions are true (normal request), then just queue it.
*/
if (*link) {
- struct io_kiocb *prev = *link;
+ struct io_kiocb *head = *link;
- sqe_copy = kmemdup(s->sqe, sizeof(*sqe_copy), GFP_KERNEL);
- if (!sqe_copy) {
- ret = -EAGAIN;
- goto err_req;
+ /*
+ * Taking sequential execution of a link, draining both sides
+ * of the link also fullfils IOSQE_IO_DRAIN semantics for all
+ * requests in the link. So, it drains the head and the
+ * next after the link request. The last one is done via
+ * drain_next flag to persist the effect across calls.
+ */
+ if (req->flags & REQ_F_IO_DRAIN) {
+ head->flags |= REQ_F_IO_DRAIN;
+ ctx->drain_next = 1;
}
+ ret = io_req_defer_prep(req, sqe);
+ if (unlikely(ret)) {
+ /* fail even hard links since we don't submit */
+ head->flags |= REQ_F_FAIL_LINK;
+ return ret;
+ }
+ trace_io_uring_link(ctx, req, head);
+ list_add_tail(&req->link_list, &head->link_list);
- s->sqe = sqe_copy;
- memcpy(&req->submit, s, sizeof(*s));
- list_add_tail(&req->list, &prev->link_list);
- } else if (s->sqe->flags & IOSQE_IO_LINK) {
- req->flags |= REQ_F_LINK;
-
- memcpy(&req->submit, s, sizeof(*s));
- INIT_LIST_HEAD(&req->link_list);
- *link = req;
+ /* last request of a link, enqueue the link */
+ if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
+ io_queue_link_head(head, cs);
+ *link = NULL;
+ }
} else {
- io_queue_sqe(ctx, req, s);
+ if (unlikely(ctx->drain_next)) {
+ req->flags |= REQ_F_IO_DRAIN;
+ ctx->drain_next = 0;
+ }
+ if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
+ req->flags |= REQ_F_LINK_HEAD;
+ INIT_LIST_HEAD(&req->link_list);
+
+ ret = io_req_defer_prep(req, sqe);
+ if (unlikely(ret))
+ req->flags |= REQ_F_FAIL_LINK;
+ *link = req;
+ } else {
+ io_queue_sqe(req, sqe, cs);
+ }
}
+
+ return 0;
}
/*
@@ -2646,20 +6511,24 @@
*/
static void io_submit_state_end(struct io_submit_state *state)
{
+ if (!list_empty(&state->comp.list))
+ io_submit_flush_completions(&state->comp);
blk_finish_plug(&state->plug);
- io_file_put(state);
+ io_state_file_put(state);
if (state->free_reqs)
- kmem_cache_free_bulk(req_cachep, state->free_reqs,
- &state->reqs[state->cur_req]);
+ kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs);
}
/*
* Start submission side cache.
*/
static void io_submit_state_start(struct io_submit_state *state,
- struct io_ring_ctx *ctx, unsigned max_ios)
+ struct io_ring_ctx *ctx, unsigned int max_ios)
{
blk_start_plug(&state->plug);
+ state->comp.nr = 0;
+ INIT_LIST_HEAD(&state->comp.list);
+ state->comp.ctx = ctx;
state->free_reqs = 0;
state->file = NULL;
state->ios_left = max_ios;
@@ -2669,27 +6538,24 @@
{
struct io_rings *rings = ctx->rings;
- if (ctx->cached_sq_head != READ_ONCE(rings->sq.head)) {
- /*
- * Ensure any loads from the SQEs are done at this point,
- * since once we write the new head, the application could
- * write new data to them.
- */
- smp_store_release(&rings->sq.head, ctx->cached_sq_head);
- }
+ /*
+ * Ensure any loads from the SQEs are done at this point,
+ * since once we write the new head, the application could
+ * write new data to them.
+ */
+ smp_store_release(&rings->sq.head, ctx->cached_sq_head);
}
/*
- * Fetch an sqe, if one is available. Note that s->sqe will point to memory
+ * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
* that is mapped by userspace. This means that care needs to be taken to
* ensure that reads are stable, as we cannot rely on userspace always
* being a good citizen. If members of the sqe are validated and then later
* used, it's important that those reads are done through READ_ONCE() to
* prevent a re-load down the line.
*/
-static bool io_get_sqring(struct io_ring_ctx *ctx, struct sqe_submit *s)
+static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
{
- struct io_rings *rings = ctx->rings;
u32 *sq_array = ctx->sq_array;
unsigned head;
@@ -2701,282 +6567,405 @@
* 2) allows the kernel side to track the head on its own, even
* though the application is the one updating it.
*/
- head = ctx->cached_sq_head;
- /* make sure SQ entry isn't read before tail */
- if (head == smp_load_acquire(&rings->sq.tail))
- return false;
-
- head = READ_ONCE(sq_array[head & ctx->sq_mask]);
- if (head < ctx->sq_entries) {
- s->index = head;
- s->sqe = &ctx->sq_sqes[head];
- s->opcode = READ_ONCE(s->sqe->opcode);
- s->sequence = ctx->cached_sq_head;
- ctx->cached_sq_head++;
- return true;
- }
+ head = READ_ONCE(sq_array[ctx->cached_sq_head & ctx->sq_mask]);
+ if (likely(head < ctx->sq_entries))
+ return &ctx->sq_sqes[head];
/* drop invalid entries */
- ctx->cached_sq_head++;
ctx->cached_sq_dropped++;
- WRITE_ONCE(rings->sq_dropped, ctx->cached_sq_dropped);
- return false;
+ WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped);
+ return NULL;
}
-static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
- bool has_user, bool mm_fault)
+static inline void io_consume_sqe(struct io_ring_ctx *ctx)
{
- struct io_submit_state state, *statep = NULL;
+ ctx->cached_sq_head++;
+}
+
+/*
+ * Check SQE restrictions (opcode and flags).
+ *
+ * Returns 'true' if SQE is allowed, 'false' otherwise.
+ */
+static inline bool io_check_restriction(struct io_ring_ctx *ctx,
+ struct io_kiocb *req,
+ unsigned int sqe_flags)
+{
+ if (!ctx->restricted)
+ return true;
+
+ if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
+ return false;
+
+ if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
+ ctx->restrictions.sqe_flags_required)
+ return false;
+
+ if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
+ ctx->restrictions.sqe_flags_required))
+ return false;
+
+ return true;
+}
+
+#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
+ IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
+ IOSQE_BUFFER_SELECT)
+
+static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
+ const struct io_uring_sqe *sqe,
+ struct io_submit_state *state)
+{
+ unsigned int sqe_flags;
+ int id, ret;
+
+ req->opcode = READ_ONCE(sqe->opcode);
+ req->user_data = READ_ONCE(sqe->user_data);
+ req->async_data = NULL;
+ req->file = NULL;
+ req->ctx = ctx;
+ req->flags = 0;
+ /* one is dropped after submission, the other at completion */
+ refcount_set(&req->refs, 2);
+ req->task = current;
+ req->result = 0;
+
+ if (unlikely(req->opcode >= IORING_OP_LAST))
+ return -EINVAL;
+
+ if (unlikely(io_sq_thread_acquire_mm(ctx, req)))
+ return -EFAULT;
+
+ sqe_flags = READ_ONCE(sqe->flags);
+ /* enforce forwards compatibility on users */
+ if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
+ return -EINVAL;
+
+ if (unlikely(!io_check_restriction(ctx, req, sqe_flags)))
+ return -EACCES;
+
+ if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
+ !io_op_defs[req->opcode].buffer_select)
+ return -EOPNOTSUPP;
+
+ id = READ_ONCE(sqe->personality);
+ if (id) {
+ struct io_identity *iod;
+
+ iod = xa_load(&ctx->personalities, id);
+ if (unlikely(!iod))
+ return -EINVAL;
+ refcount_inc(&iod->count);
+
+ __io_req_init_async(req);
+ get_cred(iod->creds);
+ req->work.identity = iod;
+ req->work.flags |= IO_WQ_WORK_CREDS;
+ }
+
+ /* same numerical values with corresponding REQ_F_*, safe to copy */
+ req->flags |= sqe_flags;
+
+ if (!io_op_defs[req->opcode].needs_file)
+ return 0;
+
+ ret = io_req_set_file(state, req, READ_ONCE(sqe->fd));
+ state->ios_left--;
+ return ret;
+}
+
+static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
+{
+ struct io_submit_state state;
struct io_kiocb *link = NULL;
- struct io_kiocb *shadow_req = NULL;
- bool prev_was_link = false;
int i, submitted = 0;
- if (nr > IO_PLUG_THRESHOLD) {
- io_submit_state_start(&state, ctx, nr);
- statep = &state;
+ /* if we have a backlog and couldn't flush it all, return BUSY */
+ if (test_bit(0, &ctx->sq_check_overflow)) {
+ if (!__io_cqring_overflow_flush(ctx, false, NULL, NULL))
+ return -EBUSY;
}
+ /* make sure SQ entry isn't read before tail */
+ nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
+
+ if (!percpu_ref_tryget_many(&ctx->refs, nr))
+ return -EAGAIN;
+
+ percpu_counter_add(¤t->io_uring->inflight, nr);
+ refcount_add(nr, ¤t->usage);
+
+ io_submit_state_start(&state, ctx, nr);
+
for (i = 0; i < nr; i++) {
- struct sqe_submit s;
+ const struct io_uring_sqe *sqe;
+ struct io_kiocb *req;
+ int err;
- if (!io_get_sqring(ctx, &s))
+ sqe = io_get_sqe(ctx);
+ if (unlikely(!sqe)) {
+ io_consume_sqe(ctx);
break;
-
- /*
- * If previous wasn't linked and we have a linked command,
- * that's the end of the chain. Submit the previous link.
- */
- if (!prev_was_link && link) {
- io_queue_link_head(ctx, link, &link->submit, shadow_req);
- link = NULL;
- shadow_req = NULL;
}
- prev_was_link = (s.sqe->flags & IOSQE_IO_LINK) != 0;
+ req = io_alloc_req(ctx, &state);
+ if (unlikely(!req)) {
+ if (!submitted)
+ submitted = -EAGAIN;
+ break;
+ }
+ io_consume_sqe(ctx);
+ /* will complete beyond this point, count as submitted */
+ submitted++;
- if (link && (s.sqe->flags & IOSQE_IO_DRAIN)) {
- if (!shadow_req) {
- shadow_req = io_get_req(ctx, NULL);
- if (unlikely(!shadow_req))
- goto out;
- shadow_req->flags |= (REQ_F_IO_DRAIN | REQ_F_SHADOW_DRAIN);
- refcount_dec(&shadow_req->refs);
- }
- shadow_req->sequence = s.sequence;
+ err = io_init_req(ctx, req, sqe, &state);
+ if (unlikely(err)) {
+fail_req:
+ io_put_req(req);
+ io_req_complete(req, err);
+ break;
}
-out:
- if (unlikely(mm_fault)) {
- io_cqring_add_event(ctx, s.sqe->user_data,
- -EFAULT);
- } else {
- s.has_user = has_user;
- s.needs_lock = true;
- s.needs_fixed_file = true;
- io_submit_sqe(ctx, &s, statep, &link);
- submitted++;
- }
+ trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data,
+ true, io_async_submit(ctx));
+ err = io_submit_sqe(req, sqe, &link, &state.comp);
+ if (err)
+ goto fail_req;
}
+ if (unlikely(submitted != nr)) {
+ int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
+ struct io_uring_task *tctx = current->io_uring;
+ int unused = nr - ref_used;
+
+ percpu_ref_put_many(&ctx->refs, unused);
+ percpu_counter_sub(&tctx->inflight, unused);
+ put_task_struct_many(current, unused);
+ }
if (link)
- io_queue_link_head(ctx, link, &link->submit, shadow_req);
- if (statep)
- io_submit_state_end(&state);
+ io_queue_link_head(link, &state.comp);
+ io_submit_state_end(&state);
+
+ /* Commit SQ ring head once we've consumed and submitted all SQEs */
+ io_commit_sqring(ctx);
return submitted;
}
-static int io_sq_thread(void *data)
+static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
{
- struct io_ring_ctx *ctx = data;
- struct mm_struct *cur_mm = NULL;
- const struct cred *old_cred;
- mm_segment_t old_fs;
- DEFINE_WAIT(wait);
- unsigned inflight;
- unsigned long timeout;
+ /* Tell userspace we may need a wakeup call */
+ spin_lock_irq(&ctx->completion_lock);
+ ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP;
+ spin_unlock_irq(&ctx->completion_lock);
+}
- complete(&ctx->sqo_thread_started);
+static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
+{
+ spin_lock_irq(&ctx->completion_lock);
+ ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
+ spin_unlock_irq(&ctx->completion_lock);
+}
- old_fs = get_fs();
- set_fs(USER_DS);
- old_cred = override_creds(ctx->creds);
+static int io_sq_wake_function(struct wait_queue_entry *wqe, unsigned mode,
+ int sync, void *key)
+{
+ struct io_ring_ctx *ctx = container_of(wqe, struct io_ring_ctx, sqo_wait_entry);
+ int ret;
- timeout = inflight = 0;
- while (!kthread_should_park()) {
- bool mm_fault = false;
- unsigned int to_submit;
+ ret = autoremove_wake_function(wqe, mode, sync, key);
+ if (ret) {
+ unsigned long flags;
- if (inflight) {
- unsigned nr_events = 0;
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+ ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+ }
+ return ret;
+}
- if (ctx->flags & IORING_SETUP_IOPOLL) {
- /*
- * inflight is the count of the maximum possible
- * entries we submitted, but it can be smaller
- * if we dropped some of them. If we don't have
- * poll entries available, then we know that we
- * have nothing left to poll for. Reset the
- * inflight count to zero in that case.
- */
- mutex_lock(&ctx->uring_lock);
- if (!list_empty(&ctx->poll_list))
- io_iopoll_getevents(ctx, &nr_events, 0);
- else
- inflight = 0;
- mutex_unlock(&ctx->uring_lock);
- } else {
- /*
- * Normal IO, just pretend everything completed.
- * We don't have to poll completions for that.
- */
- nr_events = inflight;
- }
+enum sq_ret {
+ SQT_IDLE = 1,
+ SQT_SPIN = 2,
+ SQT_DID_WORK = 4,
+};
- inflight -= nr_events;
- if (!inflight)
- timeout = jiffies + ctx->sq_thread_idle;
+static enum sq_ret __io_sq_thread(struct io_ring_ctx *ctx,
+ unsigned long start_jiffies, bool cap_entries)
+{
+ unsigned long timeout = start_jiffies + ctx->sq_thread_idle;
+ struct io_sq_data *sqd = ctx->sq_data;
+ unsigned int to_submit;
+ int ret = 0;
+
+again:
+ if (!list_empty(&ctx->iopoll_list)) {
+ unsigned nr_events = 0;
+
+ mutex_lock(&ctx->uring_lock);
+ if (!list_empty(&ctx->iopoll_list) && !need_resched())
+ io_do_iopoll(ctx, &nr_events, 0);
+ mutex_unlock(&ctx->uring_lock);
+ }
+
+ to_submit = io_sqring_entries(ctx);
+
+ /*
+ * If submit got -EBUSY, flag us as needing the application
+ * to enter the kernel to reap and flush events.
+ */
+ if (!to_submit || ret == -EBUSY || need_resched()) {
+ /*
+ * Drop cur_mm before scheduling, we can't hold it for
+ * long periods (or over schedule()). Do this before
+ * adding ourselves to the waitqueue, as the unuse/drop
+ * may sleep.
+ */
+ io_sq_thread_drop_mm();
+
+ /*
+ * We're polling. If we're within the defined idle
+ * period, then let us spin without work before going
+ * to sleep. The exception is if we got EBUSY doing
+ * more IO, we should wait for the application to
+ * reap events and wake us up.
+ */
+ if (!list_empty(&ctx->iopoll_list) || need_resched() ||
+ (!time_after(jiffies, timeout) && ret != -EBUSY &&
+ !percpu_ref_is_dying(&ctx->refs)))
+ return SQT_SPIN;
+
+ prepare_to_wait(&sqd->wait, &ctx->sqo_wait_entry,
+ TASK_INTERRUPTIBLE);
+
+ /*
+ * While doing polled IO, before going to sleep, we need
+ * to check if there are new reqs added to iopoll_list,
+ * it is because reqs may have been punted to io worker
+ * and will be added to iopoll_list later, hence check
+ * the iopoll_list again.
+ */
+ if ((ctx->flags & IORING_SETUP_IOPOLL) &&
+ !list_empty_careful(&ctx->iopoll_list)) {
+ finish_wait(&sqd->wait, &ctx->sqo_wait_entry);
+ goto again;
}
to_submit = io_sqring_entries(ctx);
- if (!to_submit) {
- /*
- * Drop cur_mm before scheduling, we can't hold it for
- * long periods (or over schedule()). Do this before
- * adding ourselves to the waitqueue, as the unuse/drop
- * may sleep.
- */
- if (cur_mm) {
- unuse_mm(cur_mm);
- mmput(cur_mm);
- cur_mm = NULL;
- }
-
- /*
- * We're polling. If we're within the defined idle
- * period, then let us spin without work before going
- * to sleep.
- */
- if (inflight || !time_after(jiffies, timeout)) {
- cond_resched();
- continue;
- }
-
- prepare_to_wait(&ctx->sqo_wait, &wait,
- TASK_INTERRUPTIBLE);
-
- /* Tell userspace we may need a wakeup call */
- ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP;
- /* make sure to read SQ tail after writing flags */
- smp_mb();
-
- to_submit = io_sqring_entries(ctx);
- if (!to_submit) {
- if (kthread_should_park()) {
- finish_wait(&ctx->sqo_wait, &wait);
- break;
- }
- if (signal_pending(current))
- flush_signals(current);
- schedule();
- finish_wait(&ctx->sqo_wait, &wait);
-
- ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
- continue;
- }
- finish_wait(&ctx->sqo_wait, &wait);
-
- ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
- }
-
- /* Unless all new commands are FIXED regions, grab mm */
- if (!cur_mm) {
- mm_fault = !mmget_not_zero(ctx->sqo_mm);
- if (!mm_fault) {
- use_mm(ctx->sqo_mm);
- cur_mm = ctx->sqo_mm;
- }
- }
-
- to_submit = min(to_submit, ctx->sq_entries);
- inflight += io_submit_sqes(ctx, to_submit, cur_mm != NULL,
- mm_fault);
-
- /* Commit SQ ring head once we've consumed all SQEs */
- io_commit_sqring(ctx);
+ if (!to_submit || ret == -EBUSY)
+ return SQT_IDLE;
}
- set_fs(old_fs);
- if (cur_mm) {
- unuse_mm(cur_mm);
- mmput(cur_mm);
+ finish_wait(&sqd->wait, &ctx->sqo_wait_entry);
+ io_ring_clear_wakeup_flag(ctx);
+
+ /* if we're handling multiple rings, cap submit size for fairness */
+ if (cap_entries && to_submit > 8)
+ to_submit = 8;
+
+ mutex_lock(&ctx->uring_lock);
+ if (likely(!percpu_ref_is_dying(&ctx->refs) && !ctx->sqo_dead))
+ ret = io_submit_sqes(ctx, to_submit);
+ mutex_unlock(&ctx->uring_lock);
+
+ if (!io_sqring_full(ctx) && wq_has_sleeper(&ctx->sqo_sq_wait))
+ wake_up(&ctx->sqo_sq_wait);
+
+ return SQT_DID_WORK;
+}
+
+static void io_sqd_init_new(struct io_sq_data *sqd)
+{
+ struct io_ring_ctx *ctx;
+
+ while (!list_empty(&sqd->ctx_new_list)) {
+ ctx = list_first_entry(&sqd->ctx_new_list, struct io_ring_ctx, sqd_list);
+ init_wait(&ctx->sqo_wait_entry);
+ ctx->sqo_wait_entry.func = io_sq_wake_function;
+ list_move_tail(&ctx->sqd_list, &sqd->ctx_list);
+ complete(&ctx->sq_thread_comp);
}
- revert_creds(old_cred);
+}
+
+static int io_sq_thread(void *data)
+{
+ struct cgroup_subsys_state *cur_css = NULL;
+ const struct cred *old_cred = NULL;
+ struct io_sq_data *sqd = data;
+ struct io_ring_ctx *ctx;
+ unsigned long start_jiffies;
+
+ start_jiffies = jiffies;
+ while (!kthread_should_stop()) {
+ enum sq_ret ret = 0;
+ bool cap_entries;
+
+ /*
+ * Any changes to the sqd lists are synchronized through the
+ * kthread parking. This synchronizes the thread vs users,
+ * the users are synchronized on the sqd->ctx_lock.
+ */
+ if (kthread_should_park()) {
+ kthread_parkme();
+ /*
+ * When sq thread is unparked, in case the previous park operation
+ * comes from io_put_sq_data(), which means that sq thread is going
+ * to be stopped, so here needs to have a check.
+ */
+ if (kthread_should_stop())
+ break;
+ }
+
+ if (unlikely(!list_empty(&sqd->ctx_new_list)))
+ io_sqd_init_new(sqd);
+
+ cap_entries = !list_is_singular(&sqd->ctx_list);
+
+ list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
+ if (current->cred != ctx->creds) {
+ if (old_cred)
+ revert_creds(old_cred);
+ old_cred = override_creds(ctx->creds);
+ }
+ io_sq_thread_associate_blkcg(ctx, &cur_css);
+#ifdef CONFIG_AUDIT
+ current->loginuid = ctx->loginuid;
+ current->sessionid = ctx->sessionid;
+#endif
+
+ ret |= __io_sq_thread(ctx, start_jiffies, cap_entries);
+
+ io_sq_thread_drop_mm();
+ }
+
+ if (ret & SQT_SPIN) {
+ io_run_task_work();
+ io_sq_thread_drop_mm();
+ cond_resched();
+ } else if (ret == SQT_IDLE) {
+ if (kthread_should_park())
+ continue;
+ list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
+ io_ring_set_wakeup_flag(ctx);
+ schedule();
+ start_jiffies = jiffies;
+ list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
+ io_ring_clear_wakeup_flag(ctx);
+ }
+ }
+
+ io_run_task_work();
+ io_sq_thread_drop_mm();
+
+ if (cur_css)
+ io_sq_thread_unassociate_blkcg();
+ if (old_cred)
+ revert_creds(old_cred);
kthread_parkme();
return 0;
}
-static int io_ring_submit(struct io_ring_ctx *ctx, unsigned int to_submit)
-{
- struct io_submit_state state, *statep = NULL;
- struct io_kiocb *link = NULL;
- struct io_kiocb *shadow_req = NULL;
- bool prev_was_link = false;
- int i, submit = 0;
-
- if (to_submit > IO_PLUG_THRESHOLD) {
- io_submit_state_start(&state, ctx, to_submit);
- statep = &state;
- }
-
- for (i = 0; i < to_submit; i++) {
- struct sqe_submit s;
-
- if (!io_get_sqring(ctx, &s))
- break;
-
- /*
- * If previous wasn't linked and we have a linked command,
- * that's the end of the chain. Submit the previous link.
- */
- if (!prev_was_link && link) {
- io_queue_link_head(ctx, link, &link->submit, shadow_req);
- link = NULL;
- shadow_req = NULL;
- }
- prev_was_link = (s.sqe->flags & IOSQE_IO_LINK) != 0;
-
- if (link && (s.sqe->flags & IOSQE_IO_DRAIN)) {
- if (!shadow_req) {
- shadow_req = io_get_req(ctx, NULL);
- if (unlikely(!shadow_req))
- goto out;
- shadow_req->flags |= (REQ_F_IO_DRAIN | REQ_F_SHADOW_DRAIN);
- refcount_dec(&shadow_req->refs);
- }
- shadow_req->sequence = s.sequence;
- }
-
-out:
- s.has_user = true;
- s.needs_lock = false;
- s.needs_fixed_file = false;
- submit++;
- io_submit_sqe(ctx, &s, statep, &link);
- }
-
- if (link)
- io_queue_link_head(ctx, link, &link->submit, shadow_req);
- if (statep)
- io_submit_state_end(statep);
-
- io_commit_sqring(ctx);
-
- return submit;
-}
-
struct io_wait_queue {
struct wait_queue_entry wq;
struct io_ring_ctx *ctx;
@@ -2989,11 +6978,11 @@
struct io_ring_ctx *ctx = iowq->ctx;
/*
- * Wake up if we have enough events, or if a timeout occured since we
+ * Wake up if we have enough events, or if a timeout occurred since we
* started waiting. For timeouts, we always want to return to userspace,
* regardless of event count.
*/
- return io_cqring_events(ctx->rings) >= iowq->to_wait ||
+ return io_cqring_events(ctx) >= iowq->to_wait ||
atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
}
@@ -3003,10 +6992,29 @@
struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
wq);
- if (!io_should_wake(iowq))
- return -1;
+ /*
+ * Cannot safely flush overflowed CQEs from here, ensure we wake up
+ * the task, and the next invocation will do it.
+ */
+ if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->cq_check_overflow))
+ return autoremove_wake_function(curr, mode, wake_flags, key);
+ return -1;
+}
- return autoremove_wake_function(curr, mode, wake_flags, key);
+static int io_run_task_work_sig(void)
+{
+ if (io_run_task_work())
+ return 1;
+ if (!signal_pending(current))
+ return 0;
+ if (current->jobctl & JOBCTL_TASK_WORK) {
+ spin_lock_irq(¤t->sighand->siglock);
+ current->jobctl &= ~JOBCTL_TASK_WORK;
+ recalc_sigpending();
+ spin_unlock_irq(¤t->sighand->siglock);
+ return 1;
+ }
+ return -EINTR;
}
/*
@@ -3026,10 +7034,15 @@
.to_wait = min_events,
};
struct io_rings *rings = ctx->rings;
- int ret;
+ int ret = 0;
- if (io_cqring_events(rings) >= min_events)
- return 0;
+ do {
+ io_cqring_overflow_flush(ctx, false, NULL, NULL);
+ if (io_cqring_events(ctx) >= min_events)
+ return 0;
+ if (!io_run_task_work())
+ break;
+ } while (1);
if (sig) {
#ifdef CONFIG_COMPAT
@@ -3044,24 +7057,31 @@
return ret;
}
- ret = 0;
iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
+ trace_io_uring_cqring_wait(ctx, min_events);
do {
+ io_cqring_overflow_flush(ctx, false, NULL, NULL);
prepare_to_wait_exclusive(&ctx->wait, &iowq.wq,
TASK_INTERRUPTIBLE);
+ /* make sure we run task_work before checking for signals */
+ ret = io_run_task_work_sig();
+ if (ret > 0) {
+ finish_wait(&ctx->wait, &iowq.wq);
+ continue;
+ }
+ else if (ret < 0)
+ break;
if (io_should_wake(&iowq))
break;
- schedule();
- if (signal_pending(current)) {
- ret = -ERESTARTSYS;
- break;
+ if (test_bit(0, &ctx->cq_check_overflow)) {
+ finish_wait(&ctx->wait, &iowq.wq);
+ continue;
}
+ schedule();
} while (1);
finish_wait(&ctx->wait, &iowq.wq);
- restore_saved_sigmask_unless(ret == -ERESTARTSYS);
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
+ restore_saved_sigmask_unless(ret == -EINTR);
return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
}
@@ -3079,65 +7099,207 @@
#else
int i;
- for (i = 0; i < ctx->nr_user_files; i++)
- fput(ctx->user_files[i]);
+ for (i = 0; i < ctx->nr_user_files; i++) {
+ struct file *file;
+
+ file = io_file_from_index(ctx, i);
+ if (file)
+ fput(file);
+ }
#endif
}
+static void io_file_ref_kill(struct percpu_ref *ref)
+{
+ struct fixed_file_data *data;
+
+ data = container_of(ref, struct fixed_file_data, refs);
+ complete(&data->done);
+}
+
+static void io_sqe_files_set_node(struct fixed_file_data *file_data,
+ struct fixed_file_ref_node *ref_node)
+{
+ spin_lock_bh(&file_data->lock);
+ file_data->node = ref_node;
+ list_add_tail(&ref_node->node, &file_data->ref_list);
+ spin_unlock_bh(&file_data->lock);
+ percpu_ref_get(&file_data->refs);
+}
+
static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
{
- if (!ctx->user_files)
+ struct fixed_file_data *data = ctx->file_data;
+ struct fixed_file_ref_node *backup_node, *ref_node = NULL;
+ unsigned nr_tables, i;
+ int ret;
+
+ if (!data)
return -ENXIO;
+ backup_node = alloc_fixed_file_ref_node(ctx);
+ if (!backup_node)
+ return -ENOMEM;
+
+ spin_lock_bh(&data->lock);
+ ref_node = data->node;
+ spin_unlock_bh(&data->lock);
+ if (ref_node)
+ percpu_ref_kill(&ref_node->refs);
+
+ percpu_ref_kill(&data->refs);
+
+ /* wait for all refs nodes to complete */
+ flush_delayed_work(&ctx->file_put_work);
+ do {
+ ret = wait_for_completion_interruptible(&data->done);
+ if (!ret)
+ break;
+ ret = io_run_task_work_sig();
+ if (ret < 0) {
+ percpu_ref_resurrect(&data->refs);
+ reinit_completion(&data->done);
+ io_sqe_files_set_node(data, backup_node);
+ return ret;
+ }
+ } while (1);
__io_sqe_files_unregister(ctx);
- kfree(ctx->user_files);
- ctx->user_files = NULL;
+ nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE);
+ for (i = 0; i < nr_tables; i++)
+ kfree(data->table[i].files);
+ kfree(data->table);
+ percpu_ref_exit(&data->refs);
+ kfree(data);
+ ctx->file_data = NULL;
ctx->nr_user_files = 0;
+ destroy_fixed_file_ref_node(backup_node);
return 0;
}
-static void io_sq_thread_stop(struct io_ring_ctx *ctx)
+static void io_put_sq_data(struct io_sq_data *sqd)
{
- if (ctx->sqo_thread) {
- wait_for_completion(&ctx->sqo_thread_started);
+ if (refcount_dec_and_test(&sqd->refs)) {
/*
* The park is a bit of a work-around, without it we get
* warning spews on shutdown with SQPOLL set and affinity
* set to a single CPU.
*/
- kthread_park(ctx->sqo_thread);
- kthread_stop(ctx->sqo_thread);
- ctx->sqo_thread = NULL;
+ if (sqd->thread) {
+ kthread_park(sqd->thread);
+ kthread_stop(sqd->thread);
+ }
+
+ kfree(sqd);
+ }
+}
+
+static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
+{
+ struct io_ring_ctx *ctx_attach;
+ struct io_sq_data *sqd;
+ struct fd f;
+
+ f = fdget(p->wq_fd);
+ if (!f.file)
+ return ERR_PTR(-ENXIO);
+ if (f.file->f_op != &io_uring_fops) {
+ fdput(f);
+ return ERR_PTR(-EINVAL);
+ }
+
+ ctx_attach = f.file->private_data;
+ sqd = ctx_attach->sq_data;
+ if (!sqd) {
+ fdput(f);
+ return ERR_PTR(-EINVAL);
+ }
+
+ refcount_inc(&sqd->refs);
+ fdput(f);
+ return sqd;
+}
+
+static struct io_sq_data *io_get_sq_data(struct io_uring_params *p)
+{
+ struct io_sq_data *sqd;
+
+ if (p->flags & IORING_SETUP_ATTACH_WQ)
+ return io_attach_sq_data(p);
+
+ sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
+ if (!sqd)
+ return ERR_PTR(-ENOMEM);
+
+ refcount_set(&sqd->refs, 1);
+ INIT_LIST_HEAD(&sqd->ctx_list);
+ INIT_LIST_HEAD(&sqd->ctx_new_list);
+ mutex_init(&sqd->ctx_lock);
+ mutex_init(&sqd->lock);
+ init_waitqueue_head(&sqd->wait);
+ return sqd;
+}
+
+static void io_sq_thread_unpark(struct io_sq_data *sqd)
+ __releases(&sqd->lock)
+{
+ if (!sqd->thread)
+ return;
+ kthread_unpark(sqd->thread);
+ mutex_unlock(&sqd->lock);
+}
+
+static void io_sq_thread_park(struct io_sq_data *sqd)
+ __acquires(&sqd->lock)
+{
+ if (!sqd->thread)
+ return;
+ mutex_lock(&sqd->lock);
+ kthread_park(sqd->thread);
+}
+
+static void io_sq_thread_stop(struct io_ring_ctx *ctx)
+{
+ struct io_sq_data *sqd = ctx->sq_data;
+
+ if (sqd) {
+ if (sqd->thread) {
+ /*
+ * We may arrive here from the error branch in
+ * io_sq_offload_create() where the kthread is created
+ * without being waked up, thus wake it up now to make
+ * sure the wait will complete.
+ */
+ wake_up_process(sqd->thread);
+ wait_for_completion(&ctx->sq_thread_comp);
+
+ io_sq_thread_park(sqd);
+ }
+
+ mutex_lock(&sqd->ctx_lock);
+ list_del(&ctx->sqd_list);
+ mutex_unlock(&sqd->ctx_lock);
+
+ if (sqd->thread) {
+ finish_wait(&sqd->wait, &ctx->sqo_wait_entry);
+ io_sq_thread_unpark(sqd);
+ }
+
+ io_put_sq_data(sqd);
+ ctx->sq_data = NULL;
}
}
static void io_finish_async(struct io_ring_ctx *ctx)
{
- int i;
-
io_sq_thread_stop(ctx);
- for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++) {
- if (ctx->sqo_wq[i]) {
- destroy_workqueue(ctx->sqo_wq[i]);
- ctx->sqo_wq[i] = NULL;
- }
+ if (ctx->io_wq) {
+ io_wq_destroy(ctx->io_wq);
+ ctx->io_wq = NULL;
}
}
#if defined(CONFIG_UNIX)
-static void io_destruct_skb(struct sk_buff *skb)
-{
- struct io_ring_ctx *ctx = skb->sk->sk_user_data;
- int i;
-
- for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++)
- if (ctx->sqo_wq[i])
- flush_workqueue(ctx->sqo_wq[i]);
-
- unix_destruct_scm(skb);
-}
-
/*
* Ensure the UNIX gc is aware of our file set, so we are certain that
* the io_uring can be safely unregistered on process exit, even if we have
@@ -3148,7 +7310,7 @@
struct sock *sk = ctx->ring_sock->sk;
struct scm_fp_list *fpl;
struct sk_buff *skb;
- int i;
+ int i, nr_files;
fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
if (!fpl)
@@ -3161,21 +7323,33 @@
}
skb->sk = sk;
- skb->destructor = io_destruct_skb;
+ nr_files = 0;
fpl->user = get_uid(ctx->user);
for (i = 0; i < nr; i++) {
- fpl->fp[i] = get_file(ctx->user_files[i + offset]);
- unix_inflight(fpl->user, fpl->fp[i]);
+ struct file *file = io_file_from_index(ctx, i + offset);
+
+ if (!file)
+ continue;
+ fpl->fp[nr_files] = get_file(file);
+ unix_inflight(fpl->user, fpl->fp[nr_files]);
+ nr_files++;
}
- fpl->max = fpl->count = nr;
- UNIXCB(skb).fp = fpl;
- refcount_add(skb->truesize, &sk->sk_wmem_alloc);
- skb_queue_head(&sk->sk_receive_queue, skb);
+ if (nr_files) {
+ fpl->max = SCM_MAX_FD;
+ fpl->count = nr_files;
+ UNIXCB(skb).fp = fpl;
+ skb->destructor = unix_destruct_scm;
+ refcount_add(skb->truesize, &sk->sk_wmem_alloc);
+ skb_queue_head(&sk->sk_receive_queue, skb);
- for (i = 0; i < nr; i++)
- fput(fpl->fp[i]);
+ for (i = 0; i < nr_files; i++)
+ fput(fpl->fp[i]);
+ } else {
+ kfree_skb(skb);
+ kfree(fpl);
+ }
return 0;
}
@@ -3206,7 +7380,10 @@
return 0;
while (total < ctx->nr_user_files) {
- fput(ctx->user_files[total]);
+ struct file *file = io_file_from_index(ctx, total);
+
+ if (file)
+ fput(file);
total++;
}
@@ -3219,34 +7396,255 @@
}
#endif
+static int io_sqe_alloc_file_tables(struct fixed_file_data *file_data,
+ unsigned nr_tables, unsigned nr_files)
+{
+ int i;
+
+ for (i = 0; i < nr_tables; i++) {
+ struct fixed_file_table *table = &file_data->table[i];
+ unsigned this_files;
+
+ this_files = min(nr_files, IORING_MAX_FILES_TABLE);
+ table->files = kcalloc(this_files, sizeof(struct file *),
+ GFP_KERNEL_ACCOUNT);
+ if (!table->files)
+ break;
+ nr_files -= this_files;
+ }
+
+ if (i == nr_tables)
+ return 0;
+
+ for (i = 0; i < nr_tables; i++) {
+ struct fixed_file_table *table = &file_data->table[i];
+ kfree(table->files);
+ }
+ return 1;
+}
+
+static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file)
+{
+#if defined(CONFIG_UNIX)
+ struct sock *sock = ctx->ring_sock->sk;
+ struct sk_buff_head list, *head = &sock->sk_receive_queue;
+ struct sk_buff *skb;
+ int i;
+
+ __skb_queue_head_init(&list);
+
+ /*
+ * Find the skb that holds this file in its SCM_RIGHTS. When found,
+ * remove this entry and rearrange the file array.
+ */
+ skb = skb_dequeue(head);
+ while (skb) {
+ struct scm_fp_list *fp;
+
+ fp = UNIXCB(skb).fp;
+ for (i = 0; i < fp->count; i++) {
+ int left;
+
+ if (fp->fp[i] != file)
+ continue;
+
+ unix_notinflight(fp->user, fp->fp[i]);
+ left = fp->count - 1 - i;
+ if (left) {
+ memmove(&fp->fp[i], &fp->fp[i + 1],
+ left * sizeof(struct file *));
+ }
+ fp->count--;
+ if (!fp->count) {
+ kfree_skb(skb);
+ skb = NULL;
+ } else {
+ __skb_queue_tail(&list, skb);
+ }
+ fput(file);
+ file = NULL;
+ break;
+ }
+
+ if (!file)
+ break;
+
+ __skb_queue_tail(&list, skb);
+
+ skb = skb_dequeue(head);
+ }
+
+ if (skb_peek(&list)) {
+ spin_lock_irq(&head->lock);
+ while ((skb = __skb_dequeue(&list)) != NULL)
+ __skb_queue_tail(head, skb);
+ spin_unlock_irq(&head->lock);
+ }
+#else
+ fput(file);
+#endif
+}
+
+struct io_file_put {
+ struct list_head list;
+ struct file *file;
+};
+
+static void __io_file_put_work(struct fixed_file_ref_node *ref_node)
+{
+ struct fixed_file_data *file_data = ref_node->file_data;
+ struct io_ring_ctx *ctx = file_data->ctx;
+ struct io_file_put *pfile, *tmp;
+
+ list_for_each_entry_safe(pfile, tmp, &ref_node->file_list, list) {
+ list_del(&pfile->list);
+ io_ring_file_put(ctx, pfile->file);
+ kfree(pfile);
+ }
+
+ percpu_ref_exit(&ref_node->refs);
+ kfree(ref_node);
+ percpu_ref_put(&file_data->refs);
+}
+
+static void io_file_put_work(struct work_struct *work)
+{
+ struct io_ring_ctx *ctx;
+ struct llist_node *node;
+
+ ctx = container_of(work, struct io_ring_ctx, file_put_work.work);
+ node = llist_del_all(&ctx->file_put_llist);
+
+ while (node) {
+ struct fixed_file_ref_node *ref_node;
+ struct llist_node *next = node->next;
+
+ ref_node = llist_entry(node, struct fixed_file_ref_node, llist);
+ __io_file_put_work(ref_node);
+ node = next;
+ }
+}
+
+static void io_file_data_ref_zero(struct percpu_ref *ref)
+{
+ struct fixed_file_ref_node *ref_node;
+ struct fixed_file_data *data;
+ struct io_ring_ctx *ctx;
+ bool first_add = false;
+ int delay = HZ;
+
+ ref_node = container_of(ref, struct fixed_file_ref_node, refs);
+ data = ref_node->file_data;
+ ctx = data->ctx;
+
+ spin_lock_bh(&data->lock);
+ ref_node->done = true;
+
+ while (!list_empty(&data->ref_list)) {
+ ref_node = list_first_entry(&data->ref_list,
+ struct fixed_file_ref_node, node);
+ /* recycle ref nodes in order */
+ if (!ref_node->done)
+ break;
+ list_del(&ref_node->node);
+ first_add |= llist_add(&ref_node->llist, &ctx->file_put_llist);
+ }
+ spin_unlock_bh(&data->lock);
+
+ if (percpu_ref_is_dying(&data->refs))
+ delay = 0;
+
+ if (!delay)
+ mod_delayed_work(system_wq, &ctx->file_put_work, 0);
+ else if (first_add)
+ queue_delayed_work(system_wq, &ctx->file_put_work, delay);
+}
+
+static struct fixed_file_ref_node *alloc_fixed_file_ref_node(
+ struct io_ring_ctx *ctx)
+{
+ struct fixed_file_ref_node *ref_node;
+
+ ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
+ if (!ref_node)
+ return NULL;
+
+ if (percpu_ref_init(&ref_node->refs, io_file_data_ref_zero,
+ 0, GFP_KERNEL)) {
+ kfree(ref_node);
+ return NULL;
+ }
+ INIT_LIST_HEAD(&ref_node->node);
+ INIT_LIST_HEAD(&ref_node->file_list);
+ ref_node->file_data = ctx->file_data;
+ ref_node->done = false;
+ return ref_node;
+}
+
+static void destroy_fixed_file_ref_node(struct fixed_file_ref_node *ref_node)
+{
+ percpu_ref_exit(&ref_node->refs);
+ kfree(ref_node);
+}
+
static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
unsigned nr_args)
{
__s32 __user *fds = (__s32 __user *) arg;
- int fd, ret = 0;
- unsigned i;
+ unsigned nr_tables, i;
+ struct file *file;
+ int fd, ret = -ENOMEM;
+ struct fixed_file_ref_node *ref_node;
+ struct fixed_file_data *file_data;
- if (ctx->user_files)
+ if (ctx->file_data)
return -EBUSY;
if (!nr_args)
return -EINVAL;
if (nr_args > IORING_MAX_FIXED_FILES)
return -EMFILE;
+ if (nr_args > rlimit(RLIMIT_NOFILE))
+ return -EMFILE;
- ctx->user_files = kcalloc(nr_args, sizeof(struct file *), GFP_KERNEL);
- if (!ctx->user_files)
+ file_data = kzalloc(sizeof(*ctx->file_data), GFP_KERNEL_ACCOUNT);
+ if (!file_data)
return -ENOMEM;
+ file_data->ctx = ctx;
+ init_completion(&file_data->done);
+ INIT_LIST_HEAD(&file_data->ref_list);
+ spin_lock_init(&file_data->lock);
- for (i = 0; i < nr_args; i++) {
- ret = -EFAULT;
- if (copy_from_user(&fd, &fds[i], sizeof(fd)))
- break;
+ nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE);
+ file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
+ GFP_KERNEL_ACCOUNT);
+ if (!file_data->table)
+ goto out_free;
- ctx->user_files[i] = fget(fd);
+ if (percpu_ref_init(&file_data->refs, io_file_ref_kill,
+ PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
+ goto out_free;
+ if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args))
+ goto out_ref;
+ ctx->file_data = file_data;
+
+ for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
+ struct fixed_file_table *table;
+ unsigned index;
+
+ if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
+ ret = -EFAULT;
+ goto out_fput;
+ }
+ /* allow sparse sets */
+ if (fd == -1)
+ continue;
+
+ file = fget(fd);
ret = -EBADF;
- if (!ctx->user_files[i])
- break;
+ if (!file)
+ goto out_fput;
+
/*
* Don't allow io_uring instances to be registered. If UNIX
* isn't enabled, then this causes a reference cycle and this
@@ -3254,48 +7652,333 @@
* handle it just fine, but there's still no point in allowing
* a ring fd as it doesn't support regular read/write anyway.
*/
- if (ctx->user_files[i]->f_op == &io_uring_fops) {
- fput(ctx->user_files[i]);
- break;
+ if (file->f_op == &io_uring_fops) {
+ fput(file);
+ goto out_fput;
}
- ctx->nr_user_files++;
- ret = 0;
- }
-
- if (ret) {
- for (i = 0; i < ctx->nr_user_files; i++)
- fput(ctx->user_files[i]);
-
- kfree(ctx->user_files);
- ctx->user_files = NULL;
- ctx->nr_user_files = 0;
- return ret;
+ table = &file_data->table[i >> IORING_FILE_TABLE_SHIFT];
+ index = i & IORING_FILE_TABLE_MASK;
+ table->files[index] = file;
}
ret = io_sqe_files_scm(ctx);
- if (ret)
+ if (ret) {
io_sqe_files_unregister(ctx);
+ return ret;
+ }
+ ref_node = alloc_fixed_file_ref_node(ctx);
+ if (!ref_node) {
+ io_sqe_files_unregister(ctx);
+ return -ENOMEM;
+ }
+
+ io_sqe_files_set_node(file_data, ref_node);
+ return ret;
+out_fput:
+ for (i = 0; i < ctx->nr_user_files; i++) {
+ file = io_file_from_index(ctx, i);
+ if (file)
+ fput(file);
+ }
+ for (i = 0; i < nr_tables; i++)
+ kfree(file_data->table[i].files);
+ ctx->nr_user_files = 0;
+out_ref:
+ percpu_ref_exit(&file_data->refs);
+out_free:
+ kfree(file_data->table);
+ kfree(file_data);
+ ctx->file_data = NULL;
return ret;
}
-static int io_sq_offload_start(struct io_ring_ctx *ctx,
- struct io_uring_params *p)
+static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
+ int index)
+{
+#if defined(CONFIG_UNIX)
+ struct sock *sock = ctx->ring_sock->sk;
+ struct sk_buff_head *head = &sock->sk_receive_queue;
+ struct sk_buff *skb;
+
+ /*
+ * See if we can merge this file into an existing skb SCM_RIGHTS
+ * file set. If there's no room, fall back to allocating a new skb
+ * and filling it in.
+ */
+ spin_lock_irq(&head->lock);
+ skb = skb_peek(head);
+ if (skb) {
+ struct scm_fp_list *fpl = UNIXCB(skb).fp;
+
+ if (fpl->count < SCM_MAX_FD) {
+ __skb_unlink(skb, head);
+ spin_unlock_irq(&head->lock);
+ fpl->fp[fpl->count] = get_file(file);
+ unix_inflight(fpl->user, fpl->fp[fpl->count]);
+ fpl->count++;
+ spin_lock_irq(&head->lock);
+ __skb_queue_head(head, skb);
+ } else {
+ skb = NULL;
+ }
+ }
+ spin_unlock_irq(&head->lock);
+
+ if (skb) {
+ fput(file);
+ return 0;
+ }
+
+ return __io_sqe_files_scm(ctx, 1, index);
+#else
+ return 0;
+#endif
+}
+
+static int io_queue_file_removal(struct fixed_file_data *data,
+ struct file *file)
+{
+ struct io_file_put *pfile;
+ struct fixed_file_ref_node *ref_node = data->node;
+
+ pfile = kzalloc(sizeof(*pfile), GFP_KERNEL);
+ if (!pfile)
+ return -ENOMEM;
+
+ pfile->file = file;
+ list_add(&pfile->list, &ref_node->file_list);
+
+ return 0;
+}
+
+static int __io_sqe_files_update(struct io_ring_ctx *ctx,
+ struct io_uring_files_update *up,
+ unsigned nr_args)
+{
+ struct fixed_file_data *data = ctx->file_data;
+ struct fixed_file_ref_node *ref_node;
+ struct file *file;
+ __s32 __user *fds;
+ int fd, i, err;
+ __u32 done;
+ bool needs_switch = false;
+
+ if (check_add_overflow(up->offset, nr_args, &done))
+ return -EOVERFLOW;
+ if (done > ctx->nr_user_files)
+ return -EINVAL;
+
+ ref_node = alloc_fixed_file_ref_node(ctx);
+ if (!ref_node)
+ return -ENOMEM;
+
+ done = 0;
+ fds = u64_to_user_ptr(up->fds);
+ while (nr_args) {
+ struct fixed_file_table *table;
+ unsigned index;
+
+ err = 0;
+ if (copy_from_user(&fd, &fds[done], sizeof(fd))) {
+ err = -EFAULT;
+ break;
+ }
+ i = array_index_nospec(up->offset, ctx->nr_user_files);
+ table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT];
+ index = i & IORING_FILE_TABLE_MASK;
+ if (table->files[index]) {
+ file = table->files[index];
+ err = io_queue_file_removal(data, file);
+ if (err)
+ break;
+ table->files[index] = NULL;
+ needs_switch = true;
+ }
+ if (fd != -1) {
+ file = fget(fd);
+ if (!file) {
+ err = -EBADF;
+ break;
+ }
+ /*
+ * Don't allow io_uring instances to be registered. If
+ * UNIX isn't enabled, then this causes a reference
+ * cycle and this instance can never get freed. If UNIX
+ * is enabled we'll handle it just fine, but there's
+ * still no point in allowing a ring fd as it doesn't
+ * support regular read/write anyway.
+ */
+ if (file->f_op == &io_uring_fops) {
+ fput(file);
+ err = -EBADF;
+ break;
+ }
+ table->files[index] = file;
+ err = io_sqe_file_register(ctx, file, i);
+ if (err) {
+ table->files[index] = NULL;
+ fput(file);
+ break;
+ }
+ }
+ nr_args--;
+ done++;
+ up->offset++;
+ }
+
+ if (needs_switch) {
+ percpu_ref_kill(&data->node->refs);
+ io_sqe_files_set_node(data, ref_node);
+ } else
+ destroy_fixed_file_ref_node(ref_node);
+
+ return done ? done : err;
+}
+
+static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg,
+ unsigned nr_args)
+{
+ struct io_uring_files_update up;
+
+ if (!ctx->file_data)
+ return -ENXIO;
+ if (!nr_args)
+ return -EINVAL;
+ if (copy_from_user(&up, arg, sizeof(up)))
+ return -EFAULT;
+ if (up.resv)
+ return -EINVAL;
+
+ return __io_sqe_files_update(ctx, &up, nr_args);
+}
+
+static void io_free_work(struct io_wq_work *work)
+{
+ struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+
+ /* Consider that io_steal_work() relies on this ref */
+ io_put_req(req);
+}
+
+static int io_init_wq_offload(struct io_ring_ctx *ctx,
+ struct io_uring_params *p)
+{
+ struct io_wq_data data;
+ struct fd f;
+ struct io_ring_ctx *ctx_attach;
+ unsigned int concurrency;
+ int ret = 0;
+
+ data.user = ctx->user;
+ data.free_work = io_free_work;
+ data.do_work = io_wq_submit_work;
+
+ if (!(p->flags & IORING_SETUP_ATTACH_WQ)) {
+ /* Do QD, or 4 * CPUS, whatever is smallest */
+ concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
+
+ ctx->io_wq = io_wq_create(concurrency, &data);
+ if (IS_ERR(ctx->io_wq)) {
+ ret = PTR_ERR(ctx->io_wq);
+ ctx->io_wq = NULL;
+ }
+ return ret;
+ }
+
+ f = fdget(p->wq_fd);
+ if (!f.file)
+ return -EBADF;
+
+ if (f.file->f_op != &io_uring_fops) {
+ ret = -EINVAL;
+ goto out_fput;
+ }
+
+ ctx_attach = f.file->private_data;
+ /* @io_wq is protected by holding the fd */
+ if (!io_wq_get(ctx_attach->io_wq, &data)) {
+ ret = -EINVAL;
+ goto out_fput;
+ }
+
+ ctx->io_wq = ctx_attach->io_wq;
+out_fput:
+ fdput(f);
+ return ret;
+}
+
+static int io_uring_alloc_task_context(struct task_struct *task)
+{
+ struct io_uring_task *tctx;
+ int ret;
+
+ tctx = kmalloc(sizeof(*tctx), GFP_KERNEL);
+ if (unlikely(!tctx))
+ return -ENOMEM;
+
+ ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
+ if (unlikely(ret)) {
+ kfree(tctx);
+ return ret;
+ }
+
+ xa_init(&tctx->xa);
+ init_waitqueue_head(&tctx->wait);
+ tctx->last = NULL;
+ atomic_set(&tctx->in_idle, 0);
+ tctx->sqpoll = false;
+ io_init_identity(&tctx->__identity);
+ tctx->identity = &tctx->__identity;
+ task->io_uring = tctx;
+ return 0;
+}
+
+void __io_uring_free(struct task_struct *tsk)
+{
+ struct io_uring_task *tctx = tsk->io_uring;
+
+ WARN_ON_ONCE(!xa_empty(&tctx->xa));
+ WARN_ON_ONCE(refcount_read(&tctx->identity->count) != 1);
+ if (tctx->identity != &tctx->__identity)
+ kfree(tctx->identity);
+ percpu_counter_destroy(&tctx->inflight);
+ kfree(tctx);
+ tsk->io_uring = NULL;
+}
+
+static int io_sq_offload_create(struct io_ring_ctx *ctx,
+ struct io_uring_params *p)
{
int ret;
- mmgrab(current->mm);
- ctx->sqo_mm = current->mm;
-
if (ctx->flags & IORING_SETUP_SQPOLL) {
+ struct io_sq_data *sqd;
+
ret = -EPERM;
if (!capable(CAP_SYS_ADMIN))
goto err;
+ sqd = io_get_sq_data(p);
+ if (IS_ERR(sqd)) {
+ ret = PTR_ERR(sqd);
+ goto err;
+ }
+
+ ctx->sq_data = sqd;
+ io_sq_thread_park(sqd);
+ mutex_lock(&sqd->ctx_lock);
+ list_add(&ctx->sqd_list, &sqd->ctx_new_list);
+ mutex_unlock(&sqd->ctx_lock);
+ io_sq_thread_unpark(sqd);
+
ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
if (!ctx->sq_thread_idle)
ctx->sq_thread_idle = HZ;
+ if (sqd->thread)
+ goto done;
+
if (p->flags & IORING_SETUP_SQ_AFF) {
int cpu = p->sq_thread_cpu;
@@ -3305,62 +7988,54 @@
if (!cpu_online(cpu))
goto err;
- ctx->sqo_thread = kthread_create_on_cpu(io_sq_thread,
- ctx, cpu,
- "io_uring-sq");
+ sqd->thread = kthread_create_on_cpu(io_sq_thread, sqd,
+ cpu, "io_uring-sq");
} else {
- ctx->sqo_thread = kthread_create(io_sq_thread, ctx,
+ sqd->thread = kthread_create(io_sq_thread, sqd,
"io_uring-sq");
}
- if (IS_ERR(ctx->sqo_thread)) {
- ret = PTR_ERR(ctx->sqo_thread);
- ctx->sqo_thread = NULL;
+ if (IS_ERR(sqd->thread)) {
+ ret = PTR_ERR(sqd->thread);
+ sqd->thread = NULL;
goto err;
}
- wake_up_process(ctx->sqo_thread);
+ ret = io_uring_alloc_task_context(sqd->thread);
+ if (ret)
+ goto err;
} else if (p->flags & IORING_SETUP_SQ_AFF) {
/* Can't have SQ_AFF without SQPOLL */
ret = -EINVAL;
goto err;
}
- /* Do QD, or 2 * CPUS, whatever is smallest */
- ctx->sqo_wq[0] = alloc_workqueue("io_ring-wq",
- WQ_UNBOUND | WQ_FREEZABLE,
- min(ctx->sq_entries - 1, 2 * num_online_cpus()));
- if (!ctx->sqo_wq[0]) {
- ret = -ENOMEM;
+done:
+ ret = io_init_wq_offload(ctx, p);
+ if (ret)
goto err;
- }
-
- /*
- * This is for buffered writes, where we want to limit the parallelism
- * due to file locking in file systems. As "normal" buffered writes
- * should parellelize on writeout quite nicely, limit us to having 2
- * pending. This avoids massive contention on the inode when doing
- * buffered async writes.
- */
- ctx->sqo_wq[1] = alloc_workqueue("io_ring-write-wq",
- WQ_UNBOUND | WQ_FREEZABLE, 2);
- if (!ctx->sqo_wq[1]) {
- ret = -ENOMEM;
- goto err;
- }
return 0;
err:
io_finish_async(ctx);
- mmdrop(ctx->sqo_mm);
- ctx->sqo_mm = NULL;
return ret;
}
-static void io_unaccount_mem(struct user_struct *user, unsigned long nr_pages)
+static void io_sq_offload_start(struct io_ring_ctx *ctx)
+{
+ struct io_sq_data *sqd = ctx->sq_data;
+
+ ctx->flags &= ~IORING_SETUP_R_DISABLED;
+ if ((ctx->flags & IORING_SETUP_SQPOLL) && sqd && sqd->thread)
+ wake_up_process(sqd->thread);
+}
+
+static inline void __io_unaccount_mem(struct user_struct *user,
+ unsigned long nr_pages)
{
atomic_long_sub(nr_pages, &user->locked_vm);
}
-static int io_account_mem(struct user_struct *user, unsigned long nr_pages)
+static inline int __io_account_mem(struct user_struct *user,
+ unsigned long nr_pages)
{
unsigned long page_limit, cur_pages, new_pages;
@@ -3378,6 +8053,41 @@
return 0;
}
+static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages,
+ enum io_mem_account acct)
+{
+ if (ctx->limit_mem)
+ __io_unaccount_mem(ctx->user, nr_pages);
+
+ if (ctx->mm_account) {
+ if (acct == ACCT_LOCKED)
+ ctx->mm_account->locked_vm -= nr_pages;
+ else if (acct == ACCT_PINNED)
+ atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
+ }
+}
+
+static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages,
+ enum io_mem_account acct)
+{
+ int ret;
+
+ if (ctx->limit_mem) {
+ ret = __io_account_mem(ctx->user, nr_pages);
+ if (ret)
+ return ret;
+ }
+
+ if (ctx->mm_account) {
+ if (acct == ACCT_LOCKED)
+ ctx->mm_account->locked_vm += nr_pages;
+ else if (acct == ACCT_PINNED)
+ atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
+ }
+
+ return 0;
+}
+
static void io_mem_free(void *ptr)
{
struct page *page;
@@ -3450,10 +8160,10 @@
struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
for (j = 0; j < imu->nr_bvecs; j++)
- put_user_page(imu->bvec[j].bv_page);
+ unpin_user_page(imu->bvec[j].bv_page);
- if (ctx->account_mem)
- io_unaccount_mem(ctx->user, imu->nr_bvecs);
+ if (imu->acct_pages)
+ io_unaccount_mem(ctx, imu->acct_pages, ACCT_PINNED);
kvfree(imu->bvec);
imu->nr_bvecs = 0;
}
@@ -3478,7 +8188,7 @@
if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
return -EFAULT;
- dst->iov_base = (void __user *) (unsigned long) ciov.iov_base;
+ dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
dst->iov_len = ciov.iov_len;
return 0;
}
@@ -3489,11 +8199,80 @@
return 0;
}
+/*
+ * Not super efficient, but this is just a registration time. And we do cache
+ * the last compound head, so generally we'll only do a full search if we don't
+ * match that one.
+ *
+ * We check if the given compound head page has already been accounted, to
+ * avoid double accounting it. This allows us to account the full size of the
+ * page, not just the constituent pages of a huge page.
+ */
+static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
+ int nr_pages, struct page *hpage)
+{
+ int i, j;
+
+ /* check current page array */
+ for (i = 0; i < nr_pages; i++) {
+ if (!PageCompound(pages[i]))
+ continue;
+ if (compound_head(pages[i]) == hpage)
+ return true;
+ }
+
+ /* check previously registered pages */
+ for (i = 0; i < ctx->nr_user_bufs; i++) {
+ struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
+
+ for (j = 0; j < imu->nr_bvecs; j++) {
+ if (!PageCompound(imu->bvec[j].bv_page))
+ continue;
+ if (compound_head(imu->bvec[j].bv_page) == hpage)
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
+ int nr_pages, struct io_mapped_ubuf *imu,
+ struct page **last_hpage)
+{
+ int i, ret;
+
+ for (i = 0; i < nr_pages; i++) {
+ if (!PageCompound(pages[i])) {
+ imu->acct_pages++;
+ } else {
+ struct page *hpage;
+
+ hpage = compound_head(pages[i]);
+ if (hpage == *last_hpage)
+ continue;
+ *last_hpage = hpage;
+ if (headpage_already_acct(ctx, pages, i, hpage))
+ continue;
+ imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
+ }
+ }
+
+ if (!imu->acct_pages)
+ return 0;
+
+ ret = io_account_mem(ctx, imu->acct_pages, ACCT_PINNED);
+ if (ret)
+ imu->acct_pages = 0;
+ return ret;
+}
+
static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg,
unsigned nr_args)
{
struct vm_area_struct **vmas = NULL;
struct page **pages = NULL;
+ struct page *last_hpage = NULL;
int i, j, got_pages = 0;
int ret = -EINVAL;
@@ -3536,12 +8315,6 @@
start = ubuf >> PAGE_SHIFT;
nr_pages = end - start;
- if (ctx->account_mem) {
- ret = io_account_mem(ctx->user, nr_pages);
- if (ret)
- goto err;
- }
-
ret = 0;
if (!pages || nr_pages > got_pages) {
kvfree(vmas);
@@ -3553,8 +8326,6 @@
GFP_KERNEL);
if (!pages || !vmas) {
ret = -ENOMEM;
- if (ctx->account_mem)
- io_unaccount_mem(ctx->user, nr_pages);
goto err;
}
got_pages = nr_pages;
@@ -3563,15 +8334,12 @@
imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec),
GFP_KERNEL);
ret = -ENOMEM;
- if (!imu->bvec) {
- if (ctx->account_mem)
- io_unaccount_mem(ctx->user, nr_pages);
+ if (!imu->bvec)
goto err;
- }
ret = 0;
- down_read(¤t->mm->mmap_sem);
- pret = get_user_pages(ubuf, nr_pages,
+ mmap_read_lock(current->mm);
+ pret = pin_user_pages(ubuf, nr_pages,
FOLL_WRITE | FOLL_LONGTERM,
pages, vmas);
if (pret == nr_pages) {
@@ -3588,16 +8356,21 @@
} else {
ret = pret < 0 ? pret : -EFAULT;
}
- up_read(¤t->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
if (ret) {
/*
* if we did partial map, or found file backed vmas,
* release any pages we did get
*/
if (pret > 0)
- put_user_pages(pages, pret);
- if (ctx->account_mem)
- io_unaccount_mem(ctx->user, nr_pages);
+ unpin_user_pages(pages, pret);
+ kvfree(imu->bvec);
+ goto err;
+ }
+
+ ret = io_buffer_account_pin(ctx, pages, pret, imu, &last_hpage);
+ if (ret) {
+ unpin_user_pages(pages, pret);
kvfree(imu->bvec);
goto err;
}
@@ -3663,16 +8436,35 @@
return -ENXIO;
}
+static void io_destroy_buffers(struct io_ring_ctx *ctx)
+{
+ struct io_buffer *buf;
+ unsigned long index;
+
+ xa_for_each(&ctx->io_buffers, index, buf)
+ __io_remove_buffers(ctx, buf, index, -1U);
+}
+
static void io_ring_ctx_free(struct io_ring_ctx *ctx)
{
io_finish_async(ctx);
- if (ctx->sqo_mm)
- mmdrop(ctx->sqo_mm);
-
- io_iopoll_reap_events(ctx);
io_sqe_buffer_unregister(ctx);
+
+ if (ctx->sqo_task) {
+ put_task_struct(ctx->sqo_task);
+ ctx->sqo_task = NULL;
+ mmdrop(ctx->mm_account);
+ ctx->mm_account = NULL;
+ }
+
+#ifdef CONFIG_BLK_CGROUP
+ if (ctx->sqo_blkcg_css)
+ css_put(ctx->sqo_blkcg_css);
+#endif
+
io_sqe_files_unregister(ctx);
io_eventfd_unregister(ctx);
+ io_destroy_buffers(ctx);
#if defined(CONFIG_UNIX)
if (ctx->ring_sock) {
@@ -3685,12 +8477,10 @@
io_mem_free(ctx->sq_sqes);
percpu_ref_exit(&ctx->refs);
- if (ctx->account_mem)
- io_unaccount_mem(ctx->user,
- ring_pages(ctx->sq_entries, ctx->cq_entries));
free_uid(ctx->user);
- if (ctx->creds)
- put_cred(ctx->creds);
+ put_cred(ctx->creds);
+ kfree(ctx->cancel_hash);
+ kmem_cache_free(req_cachep, ctx->fallback_req);
kfree(ctx);
}
@@ -3705,10 +8495,23 @@
* io_commit_cqring
*/
smp_rmb();
- if (READ_ONCE(ctx->rings->sq.tail) - ctx->cached_sq_head !=
- ctx->rings->sq_ring_entries)
+ if (!io_sqring_full(ctx))
mask |= EPOLLOUT | EPOLLWRNORM;
- if (READ_ONCE(ctx->rings->cq.head) != ctx->cached_cq_tail)
+
+ /*
+ * Don't flush cqring overflow list here, just do a simple check.
+ * Otherwise there could possible be ABBA deadlock:
+ * CPU0 CPU1
+ * ---- ----
+ * lock(&ctx->uring_lock);
+ * lock(&ep->mtx);
+ * lock(&ctx->uring_lock);
+ * lock(&ep->mtx);
+ *
+ * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
+ * pushs them to do the flush.
+ */
+ if (io_cqring_events(ctx) || test_bit(0, &ctx->cq_check_overflow))
mask |= EPOLLIN | EPOLLRDNORM;
return mask;
@@ -3721,56 +8524,89 @@
return fasync_helper(fd, file, on, &ctx->cq_fasync);
}
-static void io_cancel_async_work(struct io_ring_ctx *ctx,
- struct files_struct *files)
+static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
{
- struct io_kiocb *req;
+ struct io_identity *iod;
- if (list_empty(&ctx->task_list))
- return;
-
- spin_lock_irq(&ctx->task_lock);
-
- list_for_each_entry(req, &ctx->task_list, task_list) {
- if (files && req->files != files)
- continue;
-
- /*
- * The below executes an smp_mb(), which matches with the
- * smp_mb() (A) in io_sq_wq_submit_work() such that either
- * we store REQ_F_CANCEL flag to req->flags or we see the
- * req->work_task setted in io_sq_wq_submit_work().
- */
- smp_store_mb(req->flags, req->flags | REQ_F_CANCEL); /* B */
-
- if (req->work_task)
- send_sig(SIGINT, req->work_task, 1);
+ iod = xa_erase(&ctx->personalities, id);
+ if (iod) {
+ put_cred(iod->creds);
+ if (refcount_dec_and_test(&iod->count))
+ kfree(iod);
+ return 0;
}
- spin_unlock_irq(&ctx->task_lock);
+
+ return -EINVAL;
+}
+
+static void io_ring_exit_work(struct work_struct *work)
+{
+ struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
+ exit_work);
+
+ /*
+ * If we're doing polled IO and end up having requests being
+ * submitted async (out-of-line), then completions can come in while
+ * we're waiting for refs to drop. We need to reap these manually,
+ * as nobody else will be looking for them.
+ */
+ do {
+ io_iopoll_try_reap_events(ctx);
+ } while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20));
+ io_ring_ctx_free(ctx);
+}
+
+static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
+{
+ struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+
+ return req->ctx == data;
}
static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
{
+ unsigned long index;
+ struct io_identify *iod;
+
mutex_lock(&ctx->uring_lock);
percpu_ref_kill(&ctx->refs);
+ /* if force is set, the ring is going away. always drop after that */
+
+ if (WARN_ON_ONCE((ctx->flags & IORING_SETUP_SQPOLL) && !ctx->sqo_dead))
+ ctx->sqo_dead = 1;
+
+ ctx->cq_overflow_flushed = 1;
+ if (ctx->rings)
+ __io_cqring_overflow_flush(ctx, true, NULL, NULL);
mutex_unlock(&ctx->uring_lock);
- io_cancel_async_work(ctx, NULL);
- io_kill_timeouts(ctx);
- io_poll_remove_all(ctx);
- io_iopoll_reap_events(ctx);
- wait_for_completion(&ctx->ctx_done);
- io_ring_ctx_free(ctx);
-}
+ io_kill_timeouts(ctx, NULL, NULL);
+ io_poll_remove_all(ctx, NULL, NULL);
-static int io_uring_flush(struct file *file, void *data)
-{
- struct io_ring_ctx *ctx = file->private_data;
+ if (ctx->io_wq)
+ io_wq_cancel_cb(ctx->io_wq, io_cancel_ctx_cb, ctx, true);
- if (fatal_signal_pending(current) || (current->flags & PF_EXITING))
- io_cancel_async_work(ctx, data);
+ /* if we failed setting up the ctx, we might not have any rings */
+ io_iopoll_try_reap_events(ctx);
+ xa_for_each(&ctx->personalities, index, iod)
+ io_unregister_personality(ctx, index);
- return 0;
+ /*
+ * Do this upfront, so we won't have a grace period where the ring
+ * is closed but resources aren't reaped yet. This can cause
+ * spurious failure in setting up a new ring.
+ */
+ io_unaccount_mem(ctx, ring_pages(ctx->sq_entries, ctx->cq_entries),
+ ACCT_LOCKED);
+
+ INIT_WORK(&ctx->exit_work, io_ring_exit_work);
+ /*
+ * Use system_unbound_wq to avoid spawning tons of event kworkers
+ * if we're exiting a ton of rings at the same time. It just adds
+ * noise and overhead, there's no discernable change in runtime
+ * over using system_wq.
+ */
+ queue_work(system_unbound_wq, &ctx->exit_work);
}
static int io_uring_release(struct inode *inode, struct file *file)
@@ -3782,12 +8618,361 @@
return 0;
}
-static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
+struct io_task_cancel {
+ struct task_struct *task;
+ struct files_struct *files;
+};
+
+static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
{
- loff_t offset = (loff_t) vma->vm_pgoff << PAGE_SHIFT;
- unsigned long sz = vma->vm_end - vma->vm_start;
+ struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+ struct io_task_cancel *cancel = data;
+ bool ret;
+
+ if (cancel->files && (req->flags & REQ_F_LINK_TIMEOUT)) {
+ unsigned long flags;
+ struct io_ring_ctx *ctx = req->ctx;
+
+ /* protect against races with linked timeouts */
+ spin_lock_irqsave(&ctx->completion_lock, flags);
+ ret = io_match_task(req, cancel->task, cancel->files);
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
+ } else {
+ ret = io_match_task(req, cancel->task, cancel->files);
+ }
+ return ret;
+}
+
+static void io_cancel_defer_files(struct io_ring_ctx *ctx,
+ struct task_struct *task,
+ struct files_struct *files)
+{
+ struct io_defer_entry *de = NULL;
+ LIST_HEAD(list);
+
+ spin_lock_irq(&ctx->completion_lock);
+ list_for_each_entry_reverse(de, &ctx->defer_list, list) {
+ if (io_match_task(de->req, task, files)) {
+ list_cut_position(&list, &ctx->defer_list, &de->list);
+ break;
+ }
+ }
+ spin_unlock_irq(&ctx->completion_lock);
+
+ while (!list_empty(&list)) {
+ de = list_first_entry(&list, struct io_defer_entry, list);
+ list_del_init(&de->list);
+ req_set_fail_links(de->req);
+ io_put_req(de->req);
+ io_req_complete(de->req, -ECANCELED);
+ kfree(de);
+ }
+}
+
+static int io_uring_count_inflight(struct io_ring_ctx *ctx,
+ struct task_struct *task,
+ struct files_struct *files)
+{
+ struct io_kiocb *req;
+ int cnt = 0;
+
+ spin_lock_irq(&ctx->inflight_lock);
+ list_for_each_entry(req, &ctx->inflight_list, inflight_entry)
+ cnt += io_match_task(req, task, files);
+ spin_unlock_irq(&ctx->inflight_lock);
+ return cnt;
+}
+
+static void io_uring_cancel_files(struct io_ring_ctx *ctx,
+ struct task_struct *task,
+ struct files_struct *files)
+{
+ while (!list_empty_careful(&ctx->inflight_list)) {
+ struct io_task_cancel cancel = { .task = task, .files = files };
+ DEFINE_WAIT(wait);
+ int inflight;
+
+ inflight = io_uring_count_inflight(ctx, task, files);
+ if (!inflight)
+ break;
+
+ io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, &cancel, true);
+ io_poll_remove_all(ctx, task, files);
+ io_kill_timeouts(ctx, task, files);
+ /* cancellations _may_ trigger task work */
+ io_run_task_work();
+
+ prepare_to_wait(&task->io_uring->wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ if (inflight == io_uring_count_inflight(ctx, task, files))
+ schedule();
+ finish_wait(&task->io_uring->wait, &wait);
+ }
+}
+
+static void __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
+ struct task_struct *task)
+{
+ while (1) {
+ struct io_task_cancel cancel = { .task = task, .files = NULL, };
+ enum io_wq_cancel cret;
+ bool ret = false;
+
+ cret = io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, &cancel, true);
+ if (cret != IO_WQ_CANCEL_NOTFOUND)
+ ret = true;
+
+ /* SQPOLL thread does its own polling */
+ if (!(ctx->flags & IORING_SETUP_SQPOLL)) {
+ while (!list_empty_careful(&ctx->iopoll_list)) {
+ io_iopoll_try_reap_events(ctx);
+ ret = true;
+ }
+ }
+
+ ret |= io_poll_remove_all(ctx, task, NULL);
+ ret |= io_kill_timeouts(ctx, task, NULL);
+ if (!ret)
+ break;
+ io_run_task_work();
+ cond_resched();
+ }
+}
+
+static void io_disable_sqo_submit(struct io_ring_ctx *ctx)
+{
+ mutex_lock(&ctx->uring_lock);
+ ctx->sqo_dead = 1;
+ if (ctx->flags & IORING_SETUP_R_DISABLED)
+ io_sq_offload_start(ctx);
+ mutex_unlock(&ctx->uring_lock);
+
+ /* make sure callers enter the ring to get error */
+ if (ctx->rings)
+ io_ring_set_wakeup_flag(ctx);
+}
+
+/*
+ * We need to iteratively cancel requests, in case a request has dependent
+ * hard links. These persist even for failure of cancelations, hence keep
+ * looping until none are found.
+ */
+static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
+ struct files_struct *files)
+{
+ struct task_struct *task = current;
+
+ if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
+ io_disable_sqo_submit(ctx);
+ task = ctx->sq_data->thread;
+ atomic_inc(&task->io_uring->in_idle);
+ io_sq_thread_park(ctx->sq_data);
+ }
+
+ io_cancel_defer_files(ctx, task, files);
+ io_cqring_overflow_flush(ctx, true, task, files);
+
+ if (!files)
+ __io_uring_cancel_task_requests(ctx, task);
+ else
+ io_uring_cancel_files(ctx, task, files);
+
+ if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
+ atomic_dec(&task->io_uring->in_idle);
+ io_sq_thread_unpark(ctx->sq_data);
+ }
+}
+
+/*
+ * Note that this task has used io_uring. We use it for cancelation purposes.
+ */
+static int io_uring_add_task_file(struct io_ring_ctx *ctx, struct file *file)
+{
+ struct io_uring_task *tctx = current->io_uring;
+ int ret;
+
+ if (unlikely(!tctx)) {
+ ret = io_uring_alloc_task_context(current);
+ if (unlikely(ret))
+ return ret;
+ tctx = current->io_uring;
+ }
+ if (tctx->last != file) {
+ void *old = xa_load(&tctx->xa, (unsigned long)file);
+
+ if (!old) {
+ get_file(file);
+ ret = xa_err(xa_store(&tctx->xa, (unsigned long)file,
+ file, GFP_KERNEL));
+ if (ret) {
+ fput(file);
+ return ret;
+ }
+ }
+ tctx->last = file;
+ }
+
+ /*
+ * This is race safe in that the task itself is doing this, hence it
+ * cannot be going through the exit/cancel paths at the same time.
+ * This cannot be modified while exit/cancel is running.
+ */
+ if (!tctx->sqpoll && (ctx->flags & IORING_SETUP_SQPOLL))
+ tctx->sqpoll = true;
+
+ return 0;
+}
+
+/*
+ * Remove this io_uring_file -> task mapping.
+ */
+static void io_uring_del_task_file(struct file *file)
+{
+ struct io_uring_task *tctx = current->io_uring;
+
+ if (tctx->last == file)
+ tctx->last = NULL;
+ file = xa_erase(&tctx->xa, (unsigned long)file);
+ if (file)
+ fput(file);
+}
+
+static void io_uring_remove_task_files(struct io_uring_task *tctx)
+{
+ struct file *file;
+ unsigned long index;
+
+ xa_for_each(&tctx->xa, index, file)
+ io_uring_del_task_file(file);
+}
+
+void __io_uring_files_cancel(struct files_struct *files)
+{
+ struct io_uring_task *tctx = current->io_uring;
+ struct file *file;
+ unsigned long index;
+
+ /* make sure overflow events are dropped */
+ atomic_inc(&tctx->in_idle);
+ xa_for_each(&tctx->xa, index, file)
+ io_uring_cancel_task_requests(file->private_data, files);
+ atomic_dec(&tctx->in_idle);
+
+ if (files)
+ io_uring_remove_task_files(tctx);
+}
+
+static s64 tctx_inflight(struct io_uring_task *tctx)
+{
+ unsigned long index;
+ struct file *file;
+ s64 inflight;
+
+ inflight = percpu_counter_sum(&tctx->inflight);
+ if (!tctx->sqpoll)
+ return inflight;
+
+ /*
+ * If we have SQPOLL rings, then we need to iterate and find them, and
+ * add the pending count for those.
+ */
+ xa_for_each(&tctx->xa, index, file) {
+ struct io_ring_ctx *ctx = file->private_data;
+
+ if (ctx->flags & IORING_SETUP_SQPOLL) {
+ struct io_uring_task *__tctx = ctx->sqo_task->io_uring;
+
+ inflight += percpu_counter_sum(&__tctx->inflight);
+ }
+ }
+
+ return inflight;
+}
+
+/*
+ * Find any io_uring fd that this task has registered or done IO on, and cancel
+ * requests.
+ */
+void __io_uring_task_cancel(void)
+{
+ struct io_uring_task *tctx = current->io_uring;
+ DEFINE_WAIT(wait);
+ s64 inflight;
+
+ /* make sure overflow events are dropped */
+ atomic_inc(&tctx->in_idle);
+
+ /* trigger io_disable_sqo_submit() */
+ if (tctx->sqpoll)
+ __io_uring_files_cancel(NULL);
+
+ do {
+ /* read completions before cancelations */
+ inflight = tctx_inflight(tctx);
+ if (!inflight)
+ break;
+ __io_uring_files_cancel(NULL);
+
+ prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
+
+ /*
+ * If we've seen completions, retry without waiting. This
+ * avoids a race where a completion comes in before we did
+ * prepare_to_wait().
+ */
+ if (inflight == tctx_inflight(tctx))
+ schedule();
+ finish_wait(&tctx->wait, &wait);
+ } while (1);
+
+ atomic_dec(&tctx->in_idle);
+
+ io_uring_remove_task_files(tctx);
+}
+
+static int io_uring_flush(struct file *file, void *data)
+{
+ struct io_uring_task *tctx = current->io_uring;
struct io_ring_ctx *ctx = file->private_data;
- unsigned long pfn;
+
+ if (fatal_signal_pending(current) || (current->flags & PF_EXITING))
+ io_uring_cancel_task_requests(ctx, NULL);
+
+ if (!tctx)
+ return 0;
+
+ /* we should have cancelled and erased it before PF_EXITING */
+ WARN_ON_ONCE((current->flags & PF_EXITING) &&
+ xa_load(&tctx->xa, (unsigned long)file));
+
+ /*
+ * fput() is pending, will be 2 if the only other ref is our potential
+ * task file note. If the task is exiting, drop regardless of count.
+ */
+ if (atomic_long_read(&file->f_count) != 2)
+ return 0;
+
+ if (ctx->flags & IORING_SETUP_SQPOLL) {
+ /* there is only one file note, which is owned by sqo_task */
+ WARN_ON_ONCE(ctx->sqo_task != current &&
+ xa_load(&tctx->xa, (unsigned long)file));
+ /* sqo_dead check is for when this happens after cancellation */
+ WARN_ON_ONCE(ctx->sqo_task == current && !ctx->sqo_dead &&
+ !xa_load(&tctx->xa, (unsigned long)file));
+
+ io_disable_sqo_submit(ctx);
+ }
+
+ if (!(ctx->flags & IORING_SETUP_SQPOLL) || ctx->sqo_task == current)
+ io_uring_del_task_file(file);
+ return 0;
+}
+
+static void *io_uring_validate_mmap_request(struct file *file,
+ loff_t pgoff, size_t sz)
+{
+ struct io_ring_ctx *ctx = file->private_data;
+ loff_t offset = pgoff << PAGE_SHIFT;
struct page *page;
void *ptr;
@@ -3800,17 +8985,86 @@
ptr = ctx->sq_sqes;
break;
default:
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
}
page = virt_to_head_page(ptr);
if (sz > page_size(page))
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
+
+ return ptr;
+}
+
+#ifdef CONFIG_MMU
+
+static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ size_t sz = vma->vm_end - vma->vm_start;
+ unsigned long pfn;
+ void *ptr;
+
+ ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
+ if (IS_ERR(ptr))
+ return PTR_ERR(ptr);
pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
}
+#else /* !CONFIG_MMU */
+
+static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
+}
+
+static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
+{
+ return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
+}
+
+static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
+ unsigned long addr, unsigned long len,
+ unsigned long pgoff, unsigned long flags)
+{
+ void *ptr;
+
+ ptr = io_uring_validate_mmap_request(file, pgoff, len);
+ if (IS_ERR(ptr))
+ return PTR_ERR(ptr);
+
+ return (unsigned long) ptr;
+}
+
+#endif /* !CONFIG_MMU */
+
+static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
+{
+ int ret = 0;
+ DEFINE_WAIT(wait);
+
+ do {
+ if (!io_sqring_full(ctx))
+ break;
+
+ prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
+
+ if (unlikely(ctx->sqo_dead)) {
+ ret = -EOWNERDEAD;
+ goto out;
+ }
+
+ if (!io_sqring_full(ctx))
+ break;
+
+ schedule();
+ } while (!signal_pending(current));
+
+ finish_wait(&ctx->sqo_sq_wait, &wait);
+out:
+ return ret;
+}
+
SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
u32, min_complete, u32, flags, const sigset_t __user *, sig,
size_t, sigsz)
@@ -3820,7 +9074,10 @@
int submitted = 0;
struct fd f;
- if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP))
+ io_run_task_work();
+
+ if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
+ IORING_ENTER_SQ_WAIT))
return -EINVAL;
f = fdget(fd);
@@ -3836,6 +9093,10 @@
if (!percpu_ref_tryget(&ctx->refs))
goto out_fput;
+ ret = -EBADFD;
+ if (ctx->flags & IORING_SETUP_R_DISABLED)
+ goto out;
+
/*
* For SQ polling, the thread will do all submissions and completions.
* Just return the requested submit count, and wake the thread if
@@ -3843,26 +9104,43 @@
*/
ret = 0;
if (ctx->flags & IORING_SETUP_SQPOLL) {
+ io_cqring_overflow_flush(ctx, false, NULL, NULL);
+
+ if (unlikely(ctx->sqo_dead)) {
+ ret = -EOWNERDEAD;
+ goto out;
+ }
if (flags & IORING_ENTER_SQ_WAKEUP)
- wake_up(&ctx->sqo_wait);
+ wake_up(&ctx->sq_data->wait);
+ if (flags & IORING_ENTER_SQ_WAIT) {
+ ret = io_sqpoll_wait_sq(ctx);
+ if (ret)
+ goto out;
+ }
submitted = to_submit;
} else if (to_submit) {
- to_submit = min(to_submit, ctx->sq_entries);
-
+ ret = io_uring_add_task_file(ctx, f.file);
+ if (unlikely(ret))
+ goto out;
mutex_lock(&ctx->uring_lock);
- submitted = io_ring_submit(ctx, to_submit);
+ submitted = io_submit_sqes(ctx, to_submit);
mutex_unlock(&ctx->uring_lock);
if (submitted != to_submit)
goto out;
}
if (flags & IORING_ENTER_GETEVENTS) {
- unsigned nr_events = 0;
-
min_complete = min(min_complete, ctx->cq_entries);
- if (ctx->flags & IORING_SETUP_IOPOLL) {
- ret = io_iopoll_check(ctx, &nr_events, min_complete);
+ /*
+ * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
+ * space applications don't need to do io completion events
+ * polling again, they can rely on io_sq_thread to do polling
+ * work, which can reduce cpu usage and uring_lock contention.
+ */
+ if (ctx->flags & IORING_SETUP_IOPOLL &&
+ !(ctx->flags & IORING_SETUP_SQPOLL)) {
+ ret = io_iopoll_check(ctx, min_complete);
} else {
ret = io_cqring_wait(ctx, min_complete, sig, sigsz);
}
@@ -3875,12 +9153,125 @@
return submitted ? submitted : ret;
}
+#ifdef CONFIG_PROC_FS
+static int io_uring_show_cred(struct seq_file *m, unsigned int id,
+ const struct io_identity *iod)
+{
+ const struct cred *cred = iod->creds;
+ struct user_namespace *uns = seq_user_ns(m);
+ struct group_info *gi;
+ kernel_cap_t cap;
+ unsigned __capi;
+ int g;
+
+ seq_printf(m, "%5d\n", id);
+ seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
+ seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
+ seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
+ seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
+ seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
+ seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
+ seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
+ seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
+ seq_puts(m, "\n\tGroups:\t");
+ gi = cred->group_info;
+ for (g = 0; g < gi->ngroups; g++) {
+ seq_put_decimal_ull(m, g ? " " : "",
+ from_kgid_munged(uns, gi->gid[g]));
+ }
+ seq_puts(m, "\n\tCapEff:\t");
+ cap = cred->cap_effective;
+ CAP_FOR_EACH_U32(__capi)
+ seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
+ seq_putc(m, '\n');
+ return 0;
+}
+
+static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
+{
+ struct io_sq_data *sq = NULL;
+ bool has_lock;
+ int i;
+
+ /*
+ * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
+ * since fdinfo case grabs it in the opposite direction of normal use
+ * cases. If we fail to get the lock, we just don't iterate any
+ * structures that could be going away outside the io_uring mutex.
+ */
+ has_lock = mutex_trylock(&ctx->uring_lock);
+
+ if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL))
+ sq = ctx->sq_data;
+
+ seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
+ seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
+ seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
+ for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
+ struct fixed_file_table *table;
+ struct file *f;
+
+ table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT];
+ f = table->files[i & IORING_FILE_TABLE_MASK];
+ if (f)
+ seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
+ else
+ seq_printf(m, "%5u: <none>\n", i);
+ }
+ seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
+ for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
+ struct io_mapped_ubuf *buf = &ctx->user_bufs[i];
+
+ seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf,
+ (unsigned int) buf->len);
+ }
+ if (has_lock && !xa_empty(&ctx->personalities)) {
+ unsigned long index;
+ const struct io_identity *iod;
+
+ seq_printf(m, "Personalities:\n");
+ xa_for_each(&ctx->personalities, index, iod)
+ io_uring_show_cred(m, index, iod);
+ }
+ seq_printf(m, "PollList:\n");
+ spin_lock_irq(&ctx->completion_lock);
+ for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
+ struct hlist_head *list = &ctx->cancel_hash[i];
+ struct io_kiocb *req;
+
+ hlist_for_each_entry(req, list, hash_node)
+ seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
+ req->task->task_works != NULL);
+ }
+ spin_unlock_irq(&ctx->completion_lock);
+ if (has_lock)
+ mutex_unlock(&ctx->uring_lock);
+}
+
+static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
+{
+ struct io_ring_ctx *ctx = f->private_data;
+
+ if (percpu_ref_tryget(&ctx->refs)) {
+ __io_uring_show_fdinfo(ctx, m);
+ percpu_ref_put(&ctx->refs);
+ }
+}
+#endif
+
static const struct file_operations io_uring_fops = {
.release = io_uring_release,
.flush = io_uring_flush,
.mmap = io_uring_mmap,
+#ifndef CONFIG_MMU
+ .get_unmapped_area = io_uring_nommu_get_unmapped_area,
+ .mmap_capabilities = io_uring_nommu_mmap_capabilities,
+#endif
.poll = io_uring_poll,
.fasync = io_uring_fasync,
+#ifdef CONFIG_PROC_FS
+ .show_fdinfo = io_uring_show_fdinfo,
+#endif
};
static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
@@ -3927,74 +9318,105 @@
return 0;
}
+static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
+{
+ int ret, fd;
+
+ fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
+ if (fd < 0)
+ return fd;
+
+ ret = io_uring_add_task_file(ctx, file);
+ if (ret) {
+ put_unused_fd(fd);
+ return ret;
+ }
+ fd_install(fd, file);
+ return fd;
+}
+
/*
* Allocate an anonymous fd, this is what constitutes the application
* visible backing of an io_uring instance. The application mmaps this
* fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
* we have to tie this fd to a socket for file garbage collection purposes.
*/
-static int io_uring_get_fd(struct io_ring_ctx *ctx)
+static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
{
struct file *file;
+#if defined(CONFIG_UNIX)
int ret;
-#if defined(CONFIG_UNIX)
ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
&ctx->ring_sock);
if (ret)
- return ret;
+ return ERR_PTR(ret);
#endif
- ret = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
- if (ret < 0)
- goto err;
-
file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
O_RDWR | O_CLOEXEC);
+#if defined(CONFIG_UNIX)
if (IS_ERR(file)) {
- put_unused_fd(ret);
- ret = PTR_ERR(file);
- goto err;
+ sock_release(ctx->ring_sock);
+ ctx->ring_sock = NULL;
+ } else {
+ ctx->ring_sock->file = file;
}
-
-#if defined(CONFIG_UNIX)
- ctx->ring_sock->file = file;
- ctx->ring_sock->sk->sk_user_data = ctx;
#endif
- fd_install(ret, file);
- return ret;
-err:
-#if defined(CONFIG_UNIX)
- sock_release(ctx->ring_sock);
- ctx->ring_sock = NULL;
-#endif
- return ret;
+ return file;
}
-static int io_uring_create(unsigned entries, struct io_uring_params *p)
+static int io_uring_create(unsigned entries, struct io_uring_params *p,
+ struct io_uring_params __user *params)
{
struct user_struct *user = NULL;
struct io_ring_ctx *ctx;
- bool account_mem;
+ struct file *file;
+ bool limit_mem;
int ret;
- if (!entries || entries > IORING_MAX_ENTRIES)
+ if (!entries)
return -EINVAL;
+ if (entries > IORING_MAX_ENTRIES) {
+ if (!(p->flags & IORING_SETUP_CLAMP))
+ return -EINVAL;
+ entries = IORING_MAX_ENTRIES;
+ }
/*
* Use twice as many entries for the CQ ring. It's possible for the
* application to drive a higher depth than the size of the SQ ring,
* since the sqes are only used at submission time. This allows for
- * some flexibility in overcommitting a bit.
+ * some flexibility in overcommitting a bit. If the application has
+ * set IORING_SETUP_CQSIZE, it will have passed in the desired number
+ * of CQ ring entries manually.
*/
p->sq_entries = roundup_pow_of_two(entries);
- p->cq_entries = 2 * p->sq_entries;
+ if (p->flags & IORING_SETUP_CQSIZE) {
+ /*
+ * If IORING_SETUP_CQSIZE is set, we do the same roundup
+ * to a power-of-two, if it isn't already. We do NOT impose
+ * any cq vs sq ring sizing.
+ */
+ if (!p->cq_entries)
+ return -EINVAL;
+ if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
+ if (!(p->flags & IORING_SETUP_CLAMP))
+ return -EINVAL;
+ p->cq_entries = IORING_MAX_CQ_ENTRIES;
+ }
+ p->cq_entries = roundup_pow_of_two(p->cq_entries);
+ if (p->cq_entries < p->sq_entries)
+ return -EINVAL;
+ } else {
+ p->cq_entries = 2 * p->sq_entries;
+ }
user = get_uid(current_user());
- account_mem = !capable(CAP_IPC_LOCK);
+ limit_mem = !capable(CAP_IPC_LOCK);
- if (account_mem) {
- ret = io_account_mem(user,
+ if (limit_mem) {
+ ret = __io_account_mem(user,
ring_pages(p->sq_entries, p->cq_entries));
if (ret) {
free_uid(user);
@@ -4004,30 +9426,70 @@
ctx = io_ring_ctx_alloc(p);
if (!ctx) {
- if (account_mem)
- io_unaccount_mem(user, ring_pages(p->sq_entries,
+ if (limit_mem)
+ __io_unaccount_mem(user, ring_pages(p->sq_entries,
p->cq_entries));
free_uid(user);
return -ENOMEM;
}
ctx->compat = in_compat_syscall();
- ctx->account_mem = account_mem;
ctx->user = user;
-
ctx->creds = get_current_cred();
- if (!ctx->creds) {
- ret = -ENOMEM;
+#ifdef CONFIG_AUDIT
+ ctx->loginuid = current->loginuid;
+ ctx->sessionid = current->sessionid;
+#endif
+ ctx->sqo_task = get_task_struct(current);
+
+ /*
+ * This is just grabbed for accounting purposes. When a process exits,
+ * the mm is exited and dropped before the files, hence we need to hang
+ * on to this mm purely for the purposes of being able to unaccount
+ * memory (locked/pinned vm). It's not used for anything else.
+ */
+ mmgrab(current->mm);
+ ctx->mm_account = current->mm;
+
+#ifdef CONFIG_BLK_CGROUP
+ /*
+ * The sq thread will belong to the original cgroup it was inited in.
+ * If the cgroup goes offline (e.g. disabling the io controller), then
+ * issued bios will be associated with the closest cgroup later in the
+ * block layer.
+ */
+ rcu_read_lock();
+ ctx->sqo_blkcg_css = blkcg_css();
+ ret = css_tryget_online(ctx->sqo_blkcg_css);
+ rcu_read_unlock();
+ if (!ret) {
+ /* don't init against a dying cgroup, have the user try again */
+ ctx->sqo_blkcg_css = NULL;
+ ret = -ENODEV;
goto err;
}
+#endif
+
+ /*
+ * Account memory _before_ installing the file descriptor. Once
+ * the descriptor is installed, it can get closed at any time. Also
+ * do this before hitting the general error path, as ring freeing
+ * will un-account as well.
+ */
+ io_account_mem(ctx, ring_pages(p->sq_entries, p->cq_entries),
+ ACCT_LOCKED);
+ ctx->limit_mem = limit_mem;
ret = io_allocate_scq_urings(ctx, p);
if (ret)
goto err;
- ret = io_sq_offload_start(ctx, p);
+ ret = io_sq_offload_create(ctx, p);
if (ret)
goto err;
+ if (!(p->flags & IORING_SETUP_R_DISABLED))
+ io_sq_offload_start(ctx);
+
memset(&p->sq_off, 0, sizeof(p->sq_off));
p->sq_off.head = offsetof(struct io_rings, sq.head);
p->sq_off.tail = offsetof(struct io_rings, sq.tail);
@@ -4044,18 +9506,40 @@
p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
p->cq_off.cqes = offsetof(struct io_rings, cqes);
+ p->cq_off.flags = offsetof(struct io_rings, cq_flags);
+
+ p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
+ IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
+ IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
+ IORING_FEAT_POLL_32BITS;
+
+ if (copy_to_user(params, p, sizeof(*p))) {
+ ret = -EFAULT;
+ goto err;
+ }
+
+ file = io_uring_get_file(ctx);
+ if (IS_ERR(file)) {
+ ret = PTR_ERR(file);
+ goto err;
+ }
/*
* Install ring fd as the very last thing, so we don't risk someone
* having closed it before we finish setup
*/
- ret = io_uring_get_fd(ctx);
- if (ret < 0)
- goto err;
+ ret = io_uring_install_fd(ctx, file);
+ if (ret < 0) {
+ io_disable_sqo_submit(ctx);
+ /* fput will clean it up */
+ fput(file);
+ return ret;
+ }
- p->features = IORING_FEAT_SINGLE_MMAP;
+ trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
return ret;
err:
+ io_disable_sqo_submit(ctx);
io_ring_ctx_wait_and_kill(ctx);
return ret;
}
@@ -4068,7 +9552,6 @@
static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
{
struct io_uring_params p;
- long ret;
int i;
if (copy_from_user(&p, params, sizeof(p)))
@@ -4079,17 +9562,12 @@
}
if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
- IORING_SETUP_SQ_AFF))
+ IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
+ IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
+ IORING_SETUP_R_DISABLED))
return -EINVAL;
- ret = io_uring_create(entries, &p);
- if (ret < 0)
- return ret;
-
- if (copy_to_user(params, &p, sizeof(p)))
- return -EFAULT;
-
- return ret;
+ return io_uring_create(entries, &p, params);
}
SYSCALL_DEFINE2(io_uring_setup, u32, entries,
@@ -4098,6 +9576,164 @@
return io_uring_setup(entries, params);
}
+static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
+{
+ struct io_uring_probe *p;
+ size_t size;
+ int i, ret;
+
+ size = struct_size(p, ops, nr_args);
+ if (size == SIZE_MAX)
+ return -EOVERFLOW;
+ p = kzalloc(size, GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ ret = -EFAULT;
+ if (copy_from_user(p, arg, size))
+ goto out;
+ ret = -EINVAL;
+ if (memchr_inv(p, 0, size))
+ goto out;
+
+ p->last_op = IORING_OP_LAST - 1;
+ if (nr_args > IORING_OP_LAST)
+ nr_args = IORING_OP_LAST;
+
+ for (i = 0; i < nr_args; i++) {
+ p->ops[i].op = i;
+ if (!io_op_defs[i].not_supported)
+ p->ops[i].flags = IO_URING_OP_SUPPORTED;
+ }
+ p->ops_len = i;
+
+ ret = 0;
+ if (copy_to_user(arg, p, size))
+ ret = -EFAULT;
+out:
+ kfree(p);
+ return ret;
+}
+
+static int io_register_personality(struct io_ring_ctx *ctx)
+{
+ struct io_identity *iod;
+ u32 id;
+ int ret;
+
+ iod = kmalloc(sizeof(*iod), GFP_KERNEL);
+ if (unlikely(!iod))
+ return -ENOMEM;
+
+ io_init_identity(iod);
+ iod->creds = get_current_cred();
+
+ ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)iod,
+ XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
+ if (ret < 0) {
+ put_cred(iod->creds);
+ kfree(iod);
+ return ret;
+ }
+ return id;
+}
+
+static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
+ unsigned int nr_args)
+{
+ struct io_uring_restriction *res;
+ size_t size;
+ int i, ret;
+
+ /* Restrictions allowed only if rings started disabled */
+ if (!(ctx->flags & IORING_SETUP_R_DISABLED))
+ return -EBADFD;
+
+ /* We allow only a single restrictions registration */
+ if (ctx->restrictions.registered)
+ return -EBUSY;
+
+ if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
+ return -EINVAL;
+
+ size = array_size(nr_args, sizeof(*res));
+ if (size == SIZE_MAX)
+ return -EOVERFLOW;
+
+ res = memdup_user(arg, size);
+ if (IS_ERR(res))
+ return PTR_ERR(res);
+
+ ret = 0;
+
+ for (i = 0; i < nr_args; i++) {
+ switch (res[i].opcode) {
+ case IORING_RESTRICTION_REGISTER_OP:
+ if (res[i].register_op >= IORING_REGISTER_LAST) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ __set_bit(res[i].register_op,
+ ctx->restrictions.register_op);
+ break;
+ case IORING_RESTRICTION_SQE_OP:
+ if (res[i].sqe_op >= IORING_OP_LAST) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
+ break;
+ case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
+ ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
+ break;
+ case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
+ ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+out:
+ /* Reset all restrictions if an error happened */
+ if (ret != 0)
+ memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
+ else
+ ctx->restrictions.registered = true;
+
+ kfree(res);
+ return ret;
+}
+
+static int io_register_enable_rings(struct io_ring_ctx *ctx)
+{
+ if (!(ctx->flags & IORING_SETUP_R_DISABLED))
+ return -EBADFD;
+
+ if (ctx->restrictions.registered)
+ ctx->restricted = 1;
+
+ io_sq_offload_start(ctx);
+ return 0;
+}
+
+static bool io_register_op_must_quiesce(int op)
+{
+ switch (op) {
+ case IORING_UNREGISTER_FILES:
+ case IORING_REGISTER_FILES_UPDATE:
+ case IORING_REGISTER_PROBE:
+ case IORING_REGISTER_PERSONALITY:
+ case IORING_UNREGISTER_PERSONALITY:
+ return false;
+ default:
+ return true;
+ }
+}
+
static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
void __user *arg, unsigned nr_args)
__releases(ctx->uring_lock)
@@ -4113,18 +9749,45 @@
if (percpu_ref_is_dying(&ctx->refs))
return -ENXIO;
- percpu_ref_kill(&ctx->refs);
+ if (io_register_op_must_quiesce(opcode)) {
+ percpu_ref_kill(&ctx->refs);
- /*
- * Drop uring mutex before waiting for references to exit. If another
- * thread is currently inside io_uring_enter() it might need to grab
- * the uring_lock to make progress. If we hold it here across the drain
- * wait, then we can deadlock. It's safe to drop the mutex here, since
- * no new references will come in after we've killed the percpu ref.
- */
- mutex_unlock(&ctx->uring_lock);
- wait_for_completion(&ctx->ctx_done);
- mutex_lock(&ctx->uring_lock);
+ /*
+ * Drop uring mutex before waiting for references to exit. If
+ * another thread is currently inside io_uring_enter() it might
+ * need to grab the uring_lock to make progress. If we hold it
+ * here across the drain wait, then we can deadlock. It's safe
+ * to drop the mutex here, since no new references will come in
+ * after we've killed the percpu ref.
+ */
+ mutex_unlock(&ctx->uring_lock);
+ do {
+ ret = wait_for_completion_interruptible(&ctx->ref_comp);
+ if (!ret)
+ break;
+ ret = io_run_task_work_sig();
+ if (ret < 0)
+ break;
+ } while (1);
+ mutex_lock(&ctx->uring_lock);
+
+ if (ret) {
+ io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
+ return ret;
+ }
+ }
+
+ if (ctx->restricted) {
+ if (opcode >= IORING_REGISTER_LAST) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (!test_bit(opcode, ctx->restrictions.register_op)) {
+ ret = -EACCES;
+ goto out;
+ }
+ }
switch (opcode) {
case IORING_REGISTER_BUFFERS:
@@ -4145,11 +9808,21 @@
break;
ret = io_sqe_files_unregister(ctx);
break;
+ case IORING_REGISTER_FILES_UPDATE:
+ ret = io_sqe_files_update(ctx, arg, nr_args);
+ break;
case IORING_REGISTER_EVENTFD:
+ case IORING_REGISTER_EVENTFD_ASYNC:
ret = -EINVAL;
if (nr_args != 1)
break;
ret = io_eventfd_register(ctx, arg);
+ if (ret)
+ break;
+ if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
+ ctx->eventfd_async = 1;
+ else
+ ctx->eventfd_async = 0;
break;
case IORING_UNREGISTER_EVENTFD:
ret = -EINVAL;
@@ -4157,14 +9830,44 @@
break;
ret = io_eventfd_unregister(ctx);
break;
+ case IORING_REGISTER_PROBE:
+ ret = -EINVAL;
+ if (!arg || nr_args > 256)
+ break;
+ ret = io_probe(ctx, arg, nr_args);
+ break;
+ case IORING_REGISTER_PERSONALITY:
+ ret = -EINVAL;
+ if (arg || nr_args)
+ break;
+ ret = io_register_personality(ctx);
+ break;
+ case IORING_UNREGISTER_PERSONALITY:
+ ret = -EINVAL;
+ if (arg)
+ break;
+ ret = io_unregister_personality(ctx, nr_args);
+ break;
+ case IORING_REGISTER_ENABLE_RINGS:
+ ret = -EINVAL;
+ if (arg || nr_args)
+ break;
+ ret = io_register_enable_rings(ctx);
+ break;
+ case IORING_REGISTER_RESTRICTIONS:
+ ret = io_register_restrictions(ctx, arg, nr_args);
+ break;
default:
ret = -EINVAL;
break;
}
- /* bring the ctx back to life */
- reinit_completion(&ctx->ctx_done);
- percpu_ref_reinit(&ctx->refs);
+out:
+ if (io_register_op_must_quiesce(opcode)) {
+ /* bring the ctx back to life */
+ percpu_ref_reinit(&ctx->refs);
+ reinit_completion(&ctx->ref_comp);
+ }
return ret;
}
@@ -4188,6 +9891,8 @@
mutex_lock(&ctx->uring_lock);
ret = __io_uring_register(ctx, opcode, arg, nr_args);
mutex_unlock(&ctx->uring_lock);
+ trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
+ ctx->cq_ev_fd != NULL, ret);
out_fput:
fdput(f);
return ret;
@@ -4195,6 +9900,45 @@
static int __init io_uring_init(void)
{
+#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
+ BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
+ BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
+} while (0)
+
+#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
+ __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
+ BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
+ BUILD_BUG_SQE_ELEM(0, __u8, opcode);
+ BUILD_BUG_SQE_ELEM(1, __u8, flags);
+ BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
+ BUILD_BUG_SQE_ELEM(4, __s32, fd);
+ BUILD_BUG_SQE_ELEM(8, __u64, off);
+ BUILD_BUG_SQE_ELEM(8, __u64, addr2);
+ BUILD_BUG_SQE_ELEM(16, __u64, addr);
+ BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
+ BUILD_BUG_SQE_ELEM(24, __u32, len);
+ BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
+ BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
+ BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
+ BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
+ BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
+ BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
+ BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
+ BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
+ BUILD_BUG_SQE_ELEM(32, __u64, user_data);
+ BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
+ BUILD_BUG_SQE_ELEM(42, __u16, personality);
+ BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
+
+ BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
+ BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
return 0;
};