v4.19.13 snapshot.
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
new file mode 100644
index 0000000..6980014
--- /dev/null
+++ b/include/linux/blkdev.h
@@ -0,0 +1,2100 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_BLKDEV_H
+#define _LINUX_BLKDEV_H
+
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+
+#ifdef CONFIG_BLOCK
+
+#include <linux/major.h>
+#include <linux/genhd.h>
+#include <linux/list.h>
+#include <linux/llist.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+#include <linux/pagemap.h>
+#include <linux/backing-dev-defs.h>
+#include <linux/wait.h>
+#include <linux/mempool.h>
+#include <linux/pfn.h>
+#include <linux/bio.h>
+#include <linux/stringify.h>
+#include <linux/gfp.h>
+#include <linux/bsg.h>
+#include <linux/smp.h>
+#include <linux/rcupdate.h>
+#include <linux/percpu-refcount.h>
+#include <linux/scatterlist.h>
+#include <linux/blkzoned.h>
+
+struct module;
+struct scsi_ioctl_command;
+
+struct request_queue;
+struct elevator_queue;
+struct blk_trace;
+struct request;
+struct sg_io_hdr;
+struct bsg_job;
+struct blkcg_gq;
+struct blk_flush_queue;
+struct pr_ops;
+struct rq_qos;
+struct blk_queue_stats;
+struct blk_stat_callback;
+
+#define BLKDEV_MIN_RQ 4
+#define BLKDEV_MAX_RQ 128 /* Default maximum */
+
+/* Must be consistent with blk_mq_poll_stats_bkt() */
+#define BLK_MQ_POLL_STATS_BKTS 16
+
+/*
+ * Maximum number of blkcg policies allowed to be registered concurrently.
+ * Defined here to simplify include dependency.
+ */
+#define BLKCG_MAX_POLS 5
+
+typedef void (rq_end_io_fn)(struct request *, blk_status_t);
+
+#define BLK_RL_SYNCFULL (1U << 0)
+#define BLK_RL_ASYNCFULL (1U << 1)
+
+struct request_list {
+ struct request_queue *q; /* the queue this rl belongs to */
+#ifdef CONFIG_BLK_CGROUP
+ struct blkcg_gq *blkg; /* blkg this request pool belongs to */
+#endif
+ /*
+ * count[], starved[], and wait[] are indexed by
+ * BLK_RW_SYNC/BLK_RW_ASYNC
+ */
+ int count[2];
+ int starved[2];
+ mempool_t *rq_pool;
+ wait_queue_head_t wait[2];
+ unsigned int flags;
+};
+
+/*
+ * request flags */
+typedef __u32 __bitwise req_flags_t;
+
+/* elevator knows about this request */
+#define RQF_SORTED ((__force req_flags_t)(1 << 0))
+/* drive already may have started this one */
+#define RQF_STARTED ((__force req_flags_t)(1 << 1))
+/* uses tagged queueing */
+#define RQF_QUEUED ((__force req_flags_t)(1 << 2))
+/* may not be passed by ioscheduler */
+#define RQF_SOFTBARRIER ((__force req_flags_t)(1 << 3))
+/* request for flush sequence */
+#define RQF_FLUSH_SEQ ((__force req_flags_t)(1 << 4))
+/* merge of different types, fail separately */
+#define RQF_MIXED_MERGE ((__force req_flags_t)(1 << 5))
+/* track inflight for MQ */
+#define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6))
+/* don't call prep for this one */
+#define RQF_DONTPREP ((__force req_flags_t)(1 << 7))
+/* set for "ide_preempt" requests and also for requests for which the SCSI
+ "quiesce" state must be ignored. */
+#define RQF_PREEMPT ((__force req_flags_t)(1 << 8))
+/* contains copies of user pages */
+#define RQF_COPY_USER ((__force req_flags_t)(1 << 9))
+/* vaguely specified driver internal error. Ignored by the block layer */
+#define RQF_FAILED ((__force req_flags_t)(1 << 10))
+/* don't warn about errors */
+#define RQF_QUIET ((__force req_flags_t)(1 << 11))
+/* elevator private data attached */
+#define RQF_ELVPRIV ((__force req_flags_t)(1 << 12))
+/* account I/O stat */
+#define RQF_IO_STAT ((__force req_flags_t)(1 << 13))
+/* request came from our alloc pool */
+#define RQF_ALLOCED ((__force req_flags_t)(1 << 14))
+/* runtime pm request */
+#define RQF_PM ((__force req_flags_t)(1 << 15))
+/* on IO scheduler merge hash */
+#define RQF_HASHED ((__force req_flags_t)(1 << 16))
+/* IO stats tracking on */
+#define RQF_STATS ((__force req_flags_t)(1 << 17))
+/* Look at ->special_vec for the actual data payload instead of the
+ bio chain. */
+#define RQF_SPECIAL_PAYLOAD ((__force req_flags_t)(1 << 18))
+/* The per-zone write lock is held for this request */
+#define RQF_ZONE_WRITE_LOCKED ((__force req_flags_t)(1 << 19))
+/* already slept for hybrid poll */
+#define RQF_MQ_POLL_SLEPT ((__force req_flags_t)(1 << 20))
+/* ->timeout has been called, don't expire again */
+#define RQF_TIMED_OUT ((__force req_flags_t)(1 << 21))
+
+/* flags that prevent us from merging requests: */
+#define RQF_NOMERGE_FLAGS \
+ (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
+
+/*
+ * Request state for blk-mq.
+ */
+enum mq_rq_state {
+ MQ_RQ_IDLE = 0,
+ MQ_RQ_IN_FLIGHT = 1,
+ MQ_RQ_COMPLETE = 2,
+};
+
+/*
+ * Try to put the fields that are referenced together in the same cacheline.
+ *
+ * If you modify this structure, make sure to update blk_rq_init() and
+ * especially blk_mq_rq_ctx_init() to take care of the added fields.
+ */
+struct request {
+ struct request_queue *q;
+ struct blk_mq_ctx *mq_ctx;
+
+ int cpu;
+ unsigned int cmd_flags; /* op and common flags */
+ req_flags_t rq_flags;
+
+ int internal_tag;
+
+ /* the following two fields are internal, NEVER access directly */
+ unsigned int __data_len; /* total data len */
+ int tag;
+ sector_t __sector; /* sector cursor */
+
+ struct bio *bio;
+ struct bio *biotail;
+
+ struct list_head queuelist;
+
+ /*
+ * The hash is used inside the scheduler, and killed once the
+ * request reaches the dispatch list. The ipi_list is only used
+ * to queue the request for softirq completion, which is long
+ * after the request has been unhashed (and even removed from
+ * the dispatch list).
+ */
+ union {
+ struct hlist_node hash; /* merge hash */
+ struct list_head ipi_list;
+ };
+
+ /*
+ * The rb_node is only used inside the io scheduler, requests
+ * are pruned when moved to the dispatch queue. So let the
+ * completion_data share space with the rb_node.
+ */
+ union {
+ struct rb_node rb_node; /* sort/lookup */
+ struct bio_vec special_vec;
+ void *completion_data;
+ int error_count; /* for legacy drivers, don't use */
+ };
+
+ /*
+ * Three pointers are available for the IO schedulers, if they need
+ * more they have to dynamically allocate it. Flush requests are
+ * never put on the IO scheduler. So let the flush fields share
+ * space with the elevator data.
+ */
+ union {
+ struct {
+ struct io_cq *icq;
+ void *priv[2];
+ } elv;
+
+ struct {
+ unsigned int seq;
+ struct list_head list;
+ rq_end_io_fn *saved_end_io;
+ } flush;
+ };
+
+ struct gendisk *rq_disk;
+ struct hd_struct *part;
+ /* Time that I/O was submitted to the kernel. */
+ u64 start_time_ns;
+ /* Time that I/O was submitted to the device. */
+ u64 io_start_time_ns;
+
+#ifdef CONFIG_BLK_WBT
+ unsigned short wbt_flags;
+#endif
+#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
+ unsigned short throtl_size;
+#endif
+
+ /*
+ * Number of scatter-gather DMA addr+len pairs after
+ * physical address coalescing is performed.
+ */
+ unsigned short nr_phys_segments;
+
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+ unsigned short nr_integrity_segments;
+#endif
+
+ unsigned short write_hint;
+ unsigned short ioprio;
+
+ void *special; /* opaque pointer available for LLD use */
+
+ unsigned int extra_len; /* length of alignment and padding */
+
+ enum mq_rq_state state;
+ refcount_t ref;
+
+ unsigned int timeout;
+
+ /* access through blk_rq_set_deadline, blk_rq_deadline */
+ unsigned long __deadline;
+
+ struct list_head timeout_list;
+
+ union {
+ struct __call_single_data csd;
+ u64 fifo_time;
+ };
+
+ /*
+ * completion callback.
+ */
+ rq_end_io_fn *end_io;
+ void *end_io_data;
+
+ /* for bidi */
+ struct request *next_rq;
+
+#ifdef CONFIG_BLK_CGROUP
+ struct request_list *rl; /* rl this rq is alloced from */
+#endif
+};
+
+static inline bool blk_op_is_scsi(unsigned int op)
+{
+ return op == REQ_OP_SCSI_IN || op == REQ_OP_SCSI_OUT;
+}
+
+static inline bool blk_op_is_private(unsigned int op)
+{
+ return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
+}
+
+static inline bool blk_rq_is_scsi(struct request *rq)
+{
+ return blk_op_is_scsi(req_op(rq));
+}
+
+static inline bool blk_rq_is_private(struct request *rq)
+{
+ return blk_op_is_private(req_op(rq));
+}
+
+static inline bool blk_rq_is_passthrough(struct request *rq)
+{
+ return blk_rq_is_scsi(rq) || blk_rq_is_private(rq);
+}
+
+static inline bool bio_is_passthrough(struct bio *bio)
+{
+ unsigned op = bio_op(bio);
+
+ return blk_op_is_scsi(op) || blk_op_is_private(op);
+}
+
+static inline unsigned short req_get_ioprio(struct request *req)
+{
+ return req->ioprio;
+}
+
+#include <linux/elevator.h>
+
+struct blk_queue_ctx;
+
+typedef void (request_fn_proc) (struct request_queue *q);
+typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
+typedef bool (poll_q_fn) (struct request_queue *q, blk_qc_t);
+typedef int (prep_rq_fn) (struct request_queue *, struct request *);
+typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
+
+struct bio_vec;
+typedef void (softirq_done_fn)(struct request *);
+typedef int (dma_drain_needed_fn)(struct request *);
+typedef int (lld_busy_fn) (struct request_queue *q);
+typedef int (bsg_job_fn) (struct bsg_job *);
+typedef int (init_rq_fn)(struct request_queue *, struct request *, gfp_t);
+typedef void (exit_rq_fn)(struct request_queue *, struct request *);
+
+enum blk_eh_timer_return {
+ BLK_EH_DONE, /* drivers has completed the command */
+ BLK_EH_RESET_TIMER, /* reset timer and try again */
+};
+
+typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
+
+enum blk_queue_state {
+ Queue_down,
+ Queue_up,
+};
+
+struct blk_queue_tag {
+ struct request **tag_index; /* map of busy tags */
+ unsigned long *tag_map; /* bit map of free/busy tags */
+ int max_depth; /* what we will send to device */
+ int real_max_depth; /* what the array can hold */
+ atomic_t refcnt; /* map can be shared */
+ int alloc_policy; /* tag allocation policy */
+ int next_tag; /* next tag */
+};
+#define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
+#define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
+
+#define BLK_SCSI_MAX_CMDS (256)
+#define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
+
+/*
+ * Zoned block device models (zoned limit).
+ */
+enum blk_zoned_model {
+ BLK_ZONED_NONE, /* Regular block device */
+ BLK_ZONED_HA, /* Host-aware zoned block device */
+ BLK_ZONED_HM, /* Host-managed zoned block device */
+};
+
+struct queue_limits {
+ unsigned long bounce_pfn;
+ unsigned long seg_boundary_mask;
+ unsigned long virt_boundary_mask;
+
+ unsigned int max_hw_sectors;
+ unsigned int max_dev_sectors;
+ unsigned int chunk_sectors;
+ unsigned int max_sectors;
+ unsigned int max_segment_size;
+ unsigned int physical_block_size;
+ unsigned int alignment_offset;
+ unsigned int io_min;
+ unsigned int io_opt;
+ unsigned int max_discard_sectors;
+ unsigned int max_hw_discard_sectors;
+ unsigned int max_write_same_sectors;
+ unsigned int max_write_zeroes_sectors;
+ unsigned int discard_granularity;
+ unsigned int discard_alignment;
+
+ unsigned short logical_block_size;
+ unsigned short max_segments;
+ unsigned short max_integrity_segments;
+ unsigned short max_discard_segments;
+
+ unsigned char misaligned;
+ unsigned char discard_misaligned;
+ unsigned char cluster;
+ unsigned char raid_partial_stripes_expensive;
+ enum blk_zoned_model zoned;
+};
+
+#ifdef CONFIG_BLK_DEV_ZONED
+
+struct blk_zone_report_hdr {
+ unsigned int nr_zones;
+ u8 padding[60];
+};
+
+extern int blkdev_report_zones(struct block_device *bdev,
+ sector_t sector, struct blk_zone *zones,
+ unsigned int *nr_zones, gfp_t gfp_mask);
+extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors,
+ sector_t nr_sectors, gfp_t gfp_mask);
+
+extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg);
+extern int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg);
+
+#else /* CONFIG_BLK_DEV_ZONED */
+
+static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
+ fmode_t mode, unsigned int cmd,
+ unsigned long arg)
+{
+ return -ENOTTY;
+}
+
+static inline int blkdev_reset_zones_ioctl(struct block_device *bdev,
+ fmode_t mode, unsigned int cmd,
+ unsigned long arg)
+{
+ return -ENOTTY;
+}
+
+#endif /* CONFIG_BLK_DEV_ZONED */
+
+struct request_queue {
+ /*
+ * Together with queue_head for cacheline sharing
+ */
+ struct list_head queue_head;
+ struct request *last_merge;
+ struct elevator_queue *elevator;
+ int nr_rqs[2]; /* # allocated [a]sync rqs */
+ int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
+
+ struct blk_queue_stats *stats;
+ struct rq_qos *rq_qos;
+
+ /*
+ * If blkcg is not used, @q->root_rl serves all requests. If blkcg
+ * is used, root blkg allocates from @q->root_rl and all other
+ * blkgs from their own blkg->rl. Which one to use should be
+ * determined using bio_request_list().
+ */
+ struct request_list root_rl;
+
+ request_fn_proc *request_fn;
+ make_request_fn *make_request_fn;
+ poll_q_fn *poll_fn;
+ prep_rq_fn *prep_rq_fn;
+ unprep_rq_fn *unprep_rq_fn;
+ softirq_done_fn *softirq_done_fn;
+ rq_timed_out_fn *rq_timed_out_fn;
+ dma_drain_needed_fn *dma_drain_needed;
+ lld_busy_fn *lld_busy_fn;
+ /* Called just after a request is allocated */
+ init_rq_fn *init_rq_fn;
+ /* Called just before a request is freed */
+ exit_rq_fn *exit_rq_fn;
+ /* Called from inside blk_get_request() */
+ void (*initialize_rq_fn)(struct request *rq);
+
+ const struct blk_mq_ops *mq_ops;
+
+ unsigned int *mq_map;
+
+ /* sw queues */
+ struct blk_mq_ctx __percpu *queue_ctx;
+ unsigned int nr_queues;
+
+ unsigned int queue_depth;
+
+ /* hw dispatch queues */
+ struct blk_mq_hw_ctx **queue_hw_ctx;
+ unsigned int nr_hw_queues;
+
+ /*
+ * Dispatch queue sorting
+ */
+ sector_t end_sector;
+ struct request *boundary_rq;
+
+ /*
+ * Delayed queue handling
+ */
+ struct delayed_work delay_work;
+
+ struct backing_dev_info *backing_dev_info;
+
+ /*
+ * The queue owner gets to use this for whatever they like.
+ * ll_rw_blk doesn't touch it.
+ */
+ void *queuedata;
+
+ /*
+ * various queue flags, see QUEUE_* below
+ */
+ unsigned long queue_flags;
+
+ /*
+ * ida allocated id for this queue. Used to index queues from
+ * ioctx.
+ */
+ int id;
+
+ /*
+ * queue needs bounce pages for pages above this limit
+ */
+ gfp_t bounce_gfp;
+
+ /*
+ * protects queue structures from reentrancy. ->__queue_lock should
+ * _never_ be used directly, it is queue private. always use
+ * ->queue_lock.
+ */
+ spinlock_t __queue_lock;
+ spinlock_t *queue_lock;
+
+ /*
+ * queue kobject
+ */
+ struct kobject kobj;
+
+ /*
+ * mq queue kobject
+ */
+ struct kobject mq_kobj;
+
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+ struct blk_integrity integrity;
+#endif /* CONFIG_BLK_DEV_INTEGRITY */
+
+#ifdef CONFIG_PM
+ struct device *dev;
+ int rpm_status;
+ unsigned int nr_pending;
+#endif
+
+ /*
+ * queue settings
+ */
+ unsigned long nr_requests; /* Max # of requests */
+ unsigned int nr_congestion_on;
+ unsigned int nr_congestion_off;
+ unsigned int nr_batching;
+
+ unsigned int dma_drain_size;
+ void *dma_drain_buffer;
+ unsigned int dma_pad_mask;
+ unsigned int dma_alignment;
+
+ struct blk_queue_tag *queue_tags;
+
+ unsigned int nr_sorted;
+ unsigned int in_flight[2];
+
+ /*
+ * Number of active block driver functions for which blk_drain_queue()
+ * must wait. Must be incremented around functions that unlock the
+ * queue_lock internally, e.g. scsi_request_fn().
+ */
+ unsigned int request_fn_active;
+
+ unsigned int rq_timeout;
+ int poll_nsec;
+
+ struct blk_stat_callback *poll_cb;
+ struct blk_rq_stat poll_stat[BLK_MQ_POLL_STATS_BKTS];
+
+ struct timer_list timeout;
+ struct work_struct timeout_work;
+ struct list_head timeout_list;
+
+ struct list_head icq_list;
+#ifdef CONFIG_BLK_CGROUP
+ DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
+ struct blkcg_gq *root_blkg;
+ struct list_head blkg_list;
+#endif
+
+ struct queue_limits limits;
+
+#ifdef CONFIG_BLK_DEV_ZONED
+ /*
+ * Zoned block device information for request dispatch control.
+ * nr_zones is the total number of zones of the device. This is always
+ * 0 for regular block devices. seq_zones_bitmap is a bitmap of nr_zones
+ * bits which indicates if a zone is conventional (bit clear) or
+ * sequential (bit set). seq_zones_wlock is a bitmap of nr_zones
+ * bits which indicates if a zone is write locked, that is, if a write
+ * request targeting the zone was dispatched. All three fields are
+ * initialized by the low level device driver (e.g. scsi/sd.c).
+ * Stacking drivers (device mappers) may or may not initialize
+ * these fields.
+ *
+ * Reads of this information must be protected with blk_queue_enter() /
+ * blk_queue_exit(). Modifying this information is only allowed while
+ * no requests are being processed. See also blk_mq_freeze_queue() and
+ * blk_mq_unfreeze_queue().
+ */
+ unsigned int nr_zones;
+ unsigned long *seq_zones_bitmap;
+ unsigned long *seq_zones_wlock;
+#endif /* CONFIG_BLK_DEV_ZONED */
+
+ /*
+ * sg stuff
+ */
+ unsigned int sg_timeout;
+ unsigned int sg_reserved_size;
+ int node;
+#ifdef CONFIG_BLK_DEV_IO_TRACE
+ struct blk_trace *blk_trace;
+ struct mutex blk_trace_mutex;
+#endif
+ /*
+ * for flush operations
+ */
+ struct blk_flush_queue *fq;
+
+ struct list_head requeue_list;
+ spinlock_t requeue_lock;
+ struct delayed_work requeue_work;
+
+ struct mutex sysfs_lock;
+
+ int bypass_depth;
+ atomic_t mq_freeze_depth;
+
+#if defined(CONFIG_BLK_DEV_BSG)
+ bsg_job_fn *bsg_job_fn;
+ struct bsg_class_device bsg_dev;
+#endif
+
+#ifdef CONFIG_BLK_DEV_THROTTLING
+ /* Throttle data */
+ struct throtl_data *td;
+#endif
+ struct rcu_head rcu_head;
+ wait_queue_head_t mq_freeze_wq;
+ struct percpu_ref q_usage_counter;
+ struct list_head all_q_node;
+
+ struct blk_mq_tag_set *tag_set;
+ struct list_head tag_set_list;
+ struct bio_set bio_split;
+
+#ifdef CONFIG_BLK_DEBUG_FS
+ struct dentry *debugfs_dir;
+ struct dentry *sched_debugfs_dir;
+#endif
+
+ bool mq_sysfs_init_done;
+
+ size_t cmd_size;
+ void *rq_alloc_data;
+
+ struct work_struct release_work;
+
+#define BLK_MAX_WRITE_HINTS 5
+ u64 write_hints[BLK_MAX_WRITE_HINTS];
+};
+
+#define QUEUE_FLAG_QUEUED 0 /* uses generic tag queueing */
+#define QUEUE_FLAG_STOPPED 1 /* queue is stopped */
+#define QUEUE_FLAG_DYING 2 /* queue being torn down */
+#define QUEUE_FLAG_BYPASS 3 /* act as dumb FIFO queue */
+#define QUEUE_FLAG_BIDI 4 /* queue supports bidi requests */
+#define QUEUE_FLAG_NOMERGES 5 /* disable merge attempts */
+#define QUEUE_FLAG_SAME_COMP 6 /* complete on same CPU-group */
+#define QUEUE_FLAG_FAIL_IO 7 /* fake timeout */
+#define QUEUE_FLAG_NONROT 9 /* non-rotational device (SSD) */
+#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
+#define QUEUE_FLAG_IO_STAT 10 /* do IO stats */
+#define QUEUE_FLAG_DISCARD 11 /* supports DISCARD */
+#define QUEUE_FLAG_NOXMERGES 12 /* No extended merges */
+#define QUEUE_FLAG_ADD_RANDOM 13 /* Contributes to random pool */
+#define QUEUE_FLAG_SECERASE 14 /* supports secure erase */
+#define QUEUE_FLAG_SAME_FORCE 15 /* force complete on same CPU */
+#define QUEUE_FLAG_DEAD 16 /* queue tear-down finished */
+#define QUEUE_FLAG_INIT_DONE 17 /* queue is initialized */
+#define QUEUE_FLAG_NO_SG_MERGE 18 /* don't attempt to merge SG segments*/
+#define QUEUE_FLAG_POLL 19 /* IO polling enabled if set */
+#define QUEUE_FLAG_WC 20 /* Write back caching */
+#define QUEUE_FLAG_FUA 21 /* device supports FUA writes */
+#define QUEUE_FLAG_FLUSH_NQ 22 /* flush not queueuable */
+#define QUEUE_FLAG_DAX 23 /* device supports DAX */
+#define QUEUE_FLAG_STATS 24 /* track rq completion times */
+#define QUEUE_FLAG_POLL_STATS 25 /* collecting stats for hybrid polling */
+#define QUEUE_FLAG_REGISTERED 26 /* queue has been registered to a disk */
+#define QUEUE_FLAG_SCSI_PASSTHROUGH 27 /* queue supports SCSI commands */
+#define QUEUE_FLAG_QUIESCED 28 /* queue has been quiesced */
+#define QUEUE_FLAG_PREEMPT_ONLY 29 /* only process REQ_PREEMPT requests */
+
+#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
+ (1 << QUEUE_FLAG_SAME_COMP) | \
+ (1 << QUEUE_FLAG_ADD_RANDOM))
+
+#define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
+ (1 << QUEUE_FLAG_SAME_COMP) | \
+ (1 << QUEUE_FLAG_POLL))
+
+void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
+void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
+bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
+bool blk_queue_flag_test_and_clear(unsigned int flag, struct request_queue *q);
+
+#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
+#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
+#define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
+#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
+#define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
+#define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
+#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
+#define blk_queue_noxmerges(q) \
+ test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
+#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
+#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
+#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
+#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
+#define blk_queue_secure_erase(q) \
+ (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
+#define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
+#define blk_queue_scsi_passthrough(q) \
+ test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
+
+#define blk_noretry_request(rq) \
+ ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
+ REQ_FAILFAST_DRIVER))
+#define blk_queue_quiesced(q) test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
+#define blk_queue_preempt_only(q) \
+ test_bit(QUEUE_FLAG_PREEMPT_ONLY, &(q)->queue_flags)
+#define blk_queue_fua(q) test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
+
+extern int blk_set_preempt_only(struct request_queue *q);
+extern void blk_clear_preempt_only(struct request_queue *q);
+
+static inline int queue_in_flight(struct request_queue *q)
+{
+ return q->in_flight[0] + q->in_flight[1];
+}
+
+static inline bool blk_account_rq(struct request *rq)
+{
+ return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
+}
+
+#define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
+#define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
+/* rq->queuelist of dequeued request must be list_empty() */
+#define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
+
+#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
+
+#define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
+
+/*
+ * Driver can handle struct request, if it either has an old style
+ * request_fn defined, or is blk-mq based.
+ */
+static inline bool queue_is_rq_based(struct request_queue *q)
+{
+ return q->request_fn || q->mq_ops;
+}
+
+static inline unsigned int blk_queue_cluster(struct request_queue *q)
+{
+ return q->limits.cluster;
+}
+
+static inline enum blk_zoned_model
+blk_queue_zoned_model(struct request_queue *q)
+{
+ return q->limits.zoned;
+}
+
+static inline bool blk_queue_is_zoned(struct request_queue *q)
+{
+ switch (blk_queue_zoned_model(q)) {
+ case BLK_ZONED_HA:
+ case BLK_ZONED_HM:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static inline unsigned int blk_queue_zone_sectors(struct request_queue *q)
+{
+ return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
+}
+
+#ifdef CONFIG_BLK_DEV_ZONED
+static inline unsigned int blk_queue_zone_no(struct request_queue *q,
+ sector_t sector)
+{
+ if (!blk_queue_is_zoned(q))
+ return 0;
+ return sector >> ilog2(q->limits.chunk_sectors);
+}
+
+static inline bool blk_queue_zone_is_seq(struct request_queue *q,
+ sector_t sector)
+{
+ if (!blk_queue_is_zoned(q) || !q->seq_zones_bitmap)
+ return false;
+ return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap);
+}
+#endif /* CONFIG_BLK_DEV_ZONED */
+
+static inline bool rq_is_sync(struct request *rq)
+{
+ return op_is_sync(rq->cmd_flags);
+}
+
+static inline bool blk_rl_full(struct request_list *rl, bool sync)
+{
+ unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
+
+ return rl->flags & flag;
+}
+
+static inline void blk_set_rl_full(struct request_list *rl, bool sync)
+{
+ unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
+
+ rl->flags |= flag;
+}
+
+static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
+{
+ unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
+
+ rl->flags &= ~flag;
+}
+
+static inline bool rq_mergeable(struct request *rq)
+{
+ if (blk_rq_is_passthrough(rq))
+ return false;
+
+ if (req_op(rq) == REQ_OP_FLUSH)
+ return false;
+
+ if (req_op(rq) == REQ_OP_WRITE_ZEROES)
+ return false;
+
+ if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
+ return false;
+ if (rq->rq_flags & RQF_NOMERGE_FLAGS)
+ return false;
+
+ return true;
+}
+
+static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
+{
+ if (bio_page(a) == bio_page(b) &&
+ bio_offset(a) == bio_offset(b))
+ return true;
+
+ return false;
+}
+
+static inline unsigned int blk_queue_depth(struct request_queue *q)
+{
+ if (q->queue_depth)
+ return q->queue_depth;
+
+ return q->nr_requests;
+}
+
+/*
+ * q->prep_rq_fn return values
+ */
+enum {
+ BLKPREP_OK, /* serve it */
+ BLKPREP_KILL, /* fatal error, kill, return -EIO */
+ BLKPREP_DEFER, /* leave on queue */
+ BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
+};
+
+extern unsigned long blk_max_low_pfn, blk_max_pfn;
+
+/*
+ * standard bounce addresses:
+ *
+ * BLK_BOUNCE_HIGH : bounce all highmem pages
+ * BLK_BOUNCE_ANY : don't bounce anything
+ * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
+ */
+
+#if BITS_PER_LONG == 32
+#define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
+#else
+#define BLK_BOUNCE_HIGH -1ULL
+#endif
+#define BLK_BOUNCE_ANY (-1ULL)
+#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
+
+/*
+ * default timeout for SG_IO if none specified
+ */
+#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
+#define BLK_MIN_SG_TIMEOUT (7 * HZ)
+
+struct rq_map_data {
+ struct page **pages;
+ int page_order;
+ int nr_entries;
+ unsigned long offset;
+ int null_mapped;
+ int from_user;
+};
+
+struct req_iterator {
+ struct bvec_iter iter;
+ struct bio *bio;
+};
+
+/* This should not be used directly - use rq_for_each_segment */
+#define for_each_bio(_bio) \
+ for (; _bio; _bio = _bio->bi_next)
+#define __rq_for_each_bio(_bio, rq) \
+ if ((rq->bio)) \
+ for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
+
+#define rq_for_each_segment(bvl, _rq, _iter) \
+ __rq_for_each_bio(_iter.bio, _rq) \
+ bio_for_each_segment(bvl, _iter.bio, _iter.iter)
+
+#define rq_iter_last(bvec, _iter) \
+ (_iter.bio->bi_next == NULL && \
+ bio_iter_last(bvec, _iter.iter))
+
+#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
+# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
+#endif
+#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
+extern void rq_flush_dcache_pages(struct request *rq);
+#else
+static inline void rq_flush_dcache_pages(struct request *rq)
+{
+}
+#endif
+
+extern int blk_register_queue(struct gendisk *disk);
+extern void blk_unregister_queue(struct gendisk *disk);
+extern blk_qc_t generic_make_request(struct bio *bio);
+extern blk_qc_t direct_make_request(struct bio *bio);
+extern void blk_rq_init(struct request_queue *q, struct request *rq);
+extern void blk_init_request_from_bio(struct request *req, struct bio *bio);
+extern void blk_put_request(struct request *);
+extern void __blk_put_request(struct request_queue *, struct request *);
+extern struct request *blk_get_request(struct request_queue *, unsigned int op,
+ blk_mq_req_flags_t flags);
+extern void blk_requeue_request(struct request_queue *, struct request *);
+extern int blk_lld_busy(struct request_queue *q);
+extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
+ struct bio_set *bs, gfp_t gfp_mask,
+ int (*bio_ctr)(struct bio *, struct bio *, void *),
+ void *data);
+extern void blk_rq_unprep_clone(struct request *rq);
+extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
+ struct request *rq);
+extern int blk_rq_append_bio(struct request *rq, struct bio **bio);
+extern void blk_delay_queue(struct request_queue *, unsigned long);
+extern void blk_queue_split(struct request_queue *, struct bio **);
+extern void blk_recount_segments(struct request_queue *, struct bio *);
+extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
+extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
+ unsigned int, void __user *);
+extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
+ unsigned int, void __user *);
+extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
+ struct scsi_ioctl_command __user *);
+
+extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
+extern void blk_queue_exit(struct request_queue *q);
+extern void blk_start_queue(struct request_queue *q);
+extern void blk_start_queue_async(struct request_queue *q);
+extern void blk_stop_queue(struct request_queue *q);
+extern void blk_sync_queue(struct request_queue *q);
+extern void __blk_stop_queue(struct request_queue *q);
+extern void __blk_run_queue(struct request_queue *q);
+extern void __blk_run_queue_uncond(struct request_queue *q);
+extern void blk_run_queue(struct request_queue *);
+extern void blk_run_queue_async(struct request_queue *q);
+extern int blk_rq_map_user(struct request_queue *, struct request *,
+ struct rq_map_data *, void __user *, unsigned long,
+ gfp_t);
+extern int blk_rq_unmap_user(struct bio *);
+extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
+extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
+ struct rq_map_data *, const struct iov_iter *,
+ gfp_t);
+extern void blk_execute_rq(struct request_queue *, struct gendisk *,
+ struct request *, int);
+extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
+ struct request *, int, rq_end_io_fn *);
+
+int blk_status_to_errno(blk_status_t status);
+blk_status_t errno_to_blk_status(int errno);
+
+bool blk_poll(struct request_queue *q, blk_qc_t cookie);
+
+static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
+{
+ return bdev->bd_disk->queue; /* this is never NULL */
+}
+
+/*
+ * The basic unit of block I/O is a sector. It is used in a number of contexts
+ * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
+ * bytes. Variables of type sector_t represent an offset or size that is a
+ * multiple of 512 bytes. Hence these two constants.
+ */
+#ifndef SECTOR_SHIFT
+#define SECTOR_SHIFT 9
+#endif
+#ifndef SECTOR_SIZE
+#define SECTOR_SIZE (1 << SECTOR_SHIFT)
+#endif
+
+/*
+ * blk_rq_pos() : the current sector
+ * blk_rq_bytes() : bytes left in the entire request
+ * blk_rq_cur_bytes() : bytes left in the current segment
+ * blk_rq_err_bytes() : bytes left till the next error boundary
+ * blk_rq_sectors() : sectors left in the entire request
+ * blk_rq_cur_sectors() : sectors left in the current segment
+ */
+static inline sector_t blk_rq_pos(const struct request *rq)
+{
+ return rq->__sector;
+}
+
+static inline unsigned int blk_rq_bytes(const struct request *rq)
+{
+ return rq->__data_len;
+}
+
+static inline int blk_rq_cur_bytes(const struct request *rq)
+{
+ return rq->bio ? bio_cur_bytes(rq->bio) : 0;
+}
+
+extern unsigned int blk_rq_err_bytes(const struct request *rq);
+
+static inline unsigned int blk_rq_sectors(const struct request *rq)
+{
+ return blk_rq_bytes(rq) >> SECTOR_SHIFT;
+}
+
+static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
+{
+ return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
+}
+
+#ifdef CONFIG_BLK_DEV_ZONED
+static inline unsigned int blk_rq_zone_no(struct request *rq)
+{
+ return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
+}
+
+static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
+{
+ return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
+}
+#endif /* CONFIG_BLK_DEV_ZONED */
+
+/*
+ * Some commands like WRITE SAME have a payload or data transfer size which
+ * is different from the size of the request. Any driver that supports such
+ * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
+ * calculate the data transfer size.
+ */
+static inline unsigned int blk_rq_payload_bytes(struct request *rq)
+{
+ if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
+ return rq->special_vec.bv_len;
+ return blk_rq_bytes(rq);
+}
+
+static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
+ int op)
+{
+ if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
+ return min(q->limits.max_discard_sectors,
+ UINT_MAX >> SECTOR_SHIFT);
+
+ if (unlikely(op == REQ_OP_WRITE_SAME))
+ return q->limits.max_write_same_sectors;
+
+ if (unlikely(op == REQ_OP_WRITE_ZEROES))
+ return q->limits.max_write_zeroes_sectors;
+
+ return q->limits.max_sectors;
+}
+
+/*
+ * Return maximum size of a request at given offset. Only valid for
+ * file system requests.
+ */
+static inline unsigned int blk_max_size_offset(struct request_queue *q,
+ sector_t offset)
+{
+ if (!q->limits.chunk_sectors)
+ return q->limits.max_sectors;
+
+ return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
+ (offset & (q->limits.chunk_sectors - 1))));
+}
+
+static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
+ sector_t offset)
+{
+ struct request_queue *q = rq->q;
+
+ if (blk_rq_is_passthrough(rq))
+ return q->limits.max_hw_sectors;
+
+ if (!q->limits.chunk_sectors ||
+ req_op(rq) == REQ_OP_DISCARD ||
+ req_op(rq) == REQ_OP_SECURE_ERASE)
+ return blk_queue_get_max_sectors(q, req_op(rq));
+
+ return min(blk_max_size_offset(q, offset),
+ blk_queue_get_max_sectors(q, req_op(rq)));
+}
+
+static inline unsigned int blk_rq_count_bios(struct request *rq)
+{
+ unsigned int nr_bios = 0;
+ struct bio *bio;
+
+ __rq_for_each_bio(bio, rq)
+ nr_bios++;
+
+ return nr_bios;
+}
+
+/*
+ * Request issue related functions.
+ */
+extern struct request *blk_peek_request(struct request_queue *q);
+extern void blk_start_request(struct request *rq);
+extern struct request *blk_fetch_request(struct request_queue *q);
+
+void blk_steal_bios(struct bio_list *list, struct request *rq);
+
+/*
+ * Request completion related functions.
+ *
+ * blk_update_request() completes given number of bytes and updates
+ * the request without completing it.
+ *
+ * blk_end_request() and friends. __blk_end_request() must be called
+ * with the request queue spinlock acquired.
+ *
+ * Several drivers define their own end_request and call
+ * blk_end_request() for parts of the original function.
+ * This prevents code duplication in drivers.
+ */
+extern bool blk_update_request(struct request *rq, blk_status_t error,
+ unsigned int nr_bytes);
+extern void blk_finish_request(struct request *rq, blk_status_t error);
+extern bool blk_end_request(struct request *rq, blk_status_t error,
+ unsigned int nr_bytes);
+extern void blk_end_request_all(struct request *rq, blk_status_t error);
+extern bool __blk_end_request(struct request *rq, blk_status_t error,
+ unsigned int nr_bytes);
+extern void __blk_end_request_all(struct request *rq, blk_status_t error);
+extern bool __blk_end_request_cur(struct request *rq, blk_status_t error);
+
+extern void blk_complete_request(struct request *);
+extern void __blk_complete_request(struct request *);
+extern void blk_abort_request(struct request *);
+extern void blk_unprep_request(struct request *);
+
+/*
+ * Access functions for manipulating queue properties
+ */
+extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
+ spinlock_t *lock, int node_id);
+extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
+extern int blk_init_allocated_queue(struct request_queue *);
+extern void blk_cleanup_queue(struct request_queue *);
+extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
+extern void blk_queue_bounce_limit(struct request_queue *, u64);
+extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
+extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
+extern void blk_queue_max_segments(struct request_queue *, unsigned short);
+extern void blk_queue_max_discard_segments(struct request_queue *,
+ unsigned short);
+extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
+extern void blk_queue_max_discard_sectors(struct request_queue *q,
+ unsigned int max_discard_sectors);
+extern void blk_queue_max_write_same_sectors(struct request_queue *q,
+ unsigned int max_write_same_sectors);
+extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
+ unsigned int max_write_same_sectors);
+extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
+extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
+extern void blk_queue_alignment_offset(struct request_queue *q,
+ unsigned int alignment);
+extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
+extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
+extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
+extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
+extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
+extern void blk_set_default_limits(struct queue_limits *lim);
+extern void blk_set_stacking_limits(struct queue_limits *lim);
+extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
+ sector_t offset);
+extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
+ sector_t offset);
+extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
+ sector_t offset);
+extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
+extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
+extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
+extern int blk_queue_dma_drain(struct request_queue *q,
+ dma_drain_needed_fn *dma_drain_needed,
+ void *buf, unsigned int size);
+extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
+extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
+extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
+extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
+extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
+extern void blk_queue_dma_alignment(struct request_queue *, int);
+extern void blk_queue_update_dma_alignment(struct request_queue *, int);
+extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
+extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
+extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
+extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
+extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
+
+/*
+ * Number of physical segments as sent to the device.
+ *
+ * Normally this is the number of discontiguous data segments sent by the
+ * submitter. But for data-less command like discard we might have no
+ * actual data segments submitted, but the driver might have to add it's
+ * own special payload. In that case we still return 1 here so that this
+ * special payload will be mapped.
+ */
+static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
+{
+ if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
+ return 1;
+ return rq->nr_phys_segments;
+}
+
+/*
+ * Number of discard segments (or ranges) the driver needs to fill in.
+ * Each discard bio merged into a request is counted as one segment.
+ */
+static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
+{
+ return max_t(unsigned short, rq->nr_phys_segments, 1);
+}
+
+extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
+extern void blk_dump_rq_flags(struct request *, char *);
+extern long nr_blockdev_pages(void);
+
+bool __must_check blk_get_queue(struct request_queue *);
+struct request_queue *blk_alloc_queue(gfp_t);
+struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id,
+ spinlock_t *lock);
+extern void blk_put_queue(struct request_queue *);
+extern void blk_set_queue_dying(struct request_queue *);
+
+/*
+ * block layer runtime pm functions
+ */
+#ifdef CONFIG_PM
+extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
+extern int blk_pre_runtime_suspend(struct request_queue *q);
+extern void blk_post_runtime_suspend(struct request_queue *q, int err);
+extern void blk_pre_runtime_resume(struct request_queue *q);
+extern void blk_post_runtime_resume(struct request_queue *q, int err);
+extern void blk_set_runtime_active(struct request_queue *q);
+#else
+static inline void blk_pm_runtime_init(struct request_queue *q,
+ struct device *dev) {}
+static inline int blk_pre_runtime_suspend(struct request_queue *q)
+{
+ return -ENOSYS;
+}
+static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
+static inline void blk_pre_runtime_resume(struct request_queue *q) {}
+static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
+static inline void blk_set_runtime_active(struct request_queue *q) {}
+#endif
+
+/*
+ * blk_plug permits building a queue of related requests by holding the I/O
+ * fragments for a short period. This allows merging of sequential requests
+ * into single larger request. As the requests are moved from a per-task list to
+ * the device's request_queue in a batch, this results in improved scalability
+ * as the lock contention for request_queue lock is reduced.
+ *
+ * It is ok not to disable preemption when adding the request to the plug list
+ * or when attempting a merge, because blk_schedule_flush_list() will only flush
+ * the plug list when the task sleeps by itself. For details, please see
+ * schedule() where blk_schedule_flush_plug() is called.
+ */
+struct blk_plug {
+ struct list_head list; /* requests */
+ struct list_head mq_list; /* blk-mq requests */
+ struct list_head cb_list; /* md requires an unplug callback */
+};
+#define BLK_MAX_REQUEST_COUNT 16
+#define BLK_PLUG_FLUSH_SIZE (128 * 1024)
+
+struct blk_plug_cb;
+typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
+struct blk_plug_cb {
+ struct list_head list;
+ blk_plug_cb_fn callback;
+ void *data;
+};
+extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
+ void *data, int size);
+extern void blk_start_plug(struct blk_plug *);
+extern void blk_finish_plug(struct blk_plug *);
+extern void blk_flush_plug_list(struct blk_plug *, bool);
+
+static inline void blk_flush_plug(struct task_struct *tsk)
+{
+ struct blk_plug *plug = tsk->plug;
+
+ if (plug)
+ blk_flush_plug_list(plug, false);
+}
+
+static inline void blk_schedule_flush_plug(struct task_struct *tsk)
+{
+ struct blk_plug *plug = tsk->plug;
+
+ if (plug)
+ blk_flush_plug_list(plug, true);
+}
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+ struct blk_plug *plug = tsk->plug;
+
+ return plug &&
+ (!list_empty(&plug->list) ||
+ !list_empty(&plug->mq_list) ||
+ !list_empty(&plug->cb_list));
+}
+
+/*
+ * tag stuff
+ */
+extern int blk_queue_start_tag(struct request_queue *, struct request *);
+extern struct request *blk_queue_find_tag(struct request_queue *, int);
+extern void blk_queue_end_tag(struct request_queue *, struct request *);
+extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
+extern void blk_queue_free_tags(struct request_queue *);
+extern int blk_queue_resize_tags(struct request_queue *, int);
+extern struct blk_queue_tag *blk_init_tags(int, int);
+extern void blk_free_tags(struct blk_queue_tag *);
+
+static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
+ int tag)
+{
+ if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
+ return NULL;
+ return bqt->tag_index[tag];
+}
+
+extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
+extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, struct page *page);
+
+#define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */
+
+extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
+extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, int flags,
+ struct bio **biop);
+
+#define BLKDEV_ZERO_NOUNMAP (1 << 0) /* do not free blocks */
+#define BLKDEV_ZERO_NOFALLBACK (1 << 1) /* don't write explicit zeroes */
+
+extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
+ unsigned flags);
+extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
+
+static inline int sb_issue_discard(struct super_block *sb, sector_t block,
+ sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
+{
+ return blkdev_issue_discard(sb->s_bdev,
+ block << (sb->s_blocksize_bits -
+ SECTOR_SHIFT),
+ nr_blocks << (sb->s_blocksize_bits -
+ SECTOR_SHIFT),
+ gfp_mask, flags);
+}
+static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
+ sector_t nr_blocks, gfp_t gfp_mask)
+{
+ return blkdev_issue_zeroout(sb->s_bdev,
+ block << (sb->s_blocksize_bits -
+ SECTOR_SHIFT),
+ nr_blocks << (sb->s_blocksize_bits -
+ SECTOR_SHIFT),
+ gfp_mask, 0);
+}
+
+extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
+
+enum blk_default_limits {
+ BLK_MAX_SEGMENTS = 128,
+ BLK_SAFE_MAX_SECTORS = 255,
+ BLK_DEF_MAX_SECTORS = 2560,
+ BLK_MAX_SEGMENT_SIZE = 65536,
+ BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
+};
+
+static inline unsigned long queue_segment_boundary(struct request_queue *q)
+{
+ return q->limits.seg_boundary_mask;
+}
+
+static inline unsigned long queue_virt_boundary(struct request_queue *q)
+{
+ return q->limits.virt_boundary_mask;
+}
+
+static inline unsigned int queue_max_sectors(struct request_queue *q)
+{
+ return q->limits.max_sectors;
+}
+
+static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
+{
+ return q->limits.max_hw_sectors;
+}
+
+static inline unsigned short queue_max_segments(struct request_queue *q)
+{
+ return q->limits.max_segments;
+}
+
+static inline unsigned short queue_max_discard_segments(struct request_queue *q)
+{
+ return q->limits.max_discard_segments;
+}
+
+static inline unsigned int queue_max_segment_size(struct request_queue *q)
+{
+ return q->limits.max_segment_size;
+}
+
+static inline unsigned short queue_logical_block_size(struct request_queue *q)
+{
+ int retval = 512;
+
+ if (q && q->limits.logical_block_size)
+ retval = q->limits.logical_block_size;
+
+ return retval;
+}
+
+static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
+{
+ return queue_logical_block_size(bdev_get_queue(bdev));
+}
+
+static inline unsigned int queue_physical_block_size(struct request_queue *q)
+{
+ return q->limits.physical_block_size;
+}
+
+static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
+{
+ return queue_physical_block_size(bdev_get_queue(bdev));
+}
+
+static inline unsigned int queue_io_min(struct request_queue *q)
+{
+ return q->limits.io_min;
+}
+
+static inline int bdev_io_min(struct block_device *bdev)
+{
+ return queue_io_min(bdev_get_queue(bdev));
+}
+
+static inline unsigned int queue_io_opt(struct request_queue *q)
+{
+ return q->limits.io_opt;
+}
+
+static inline int bdev_io_opt(struct block_device *bdev)
+{
+ return queue_io_opt(bdev_get_queue(bdev));
+}
+
+static inline int queue_alignment_offset(struct request_queue *q)
+{
+ if (q->limits.misaligned)
+ return -1;
+
+ return q->limits.alignment_offset;
+}
+
+static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
+{
+ unsigned int granularity = max(lim->physical_block_size, lim->io_min);
+ unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
+ << SECTOR_SHIFT;
+
+ return (granularity + lim->alignment_offset - alignment) % granularity;
+}
+
+static inline int bdev_alignment_offset(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q->limits.misaligned)
+ return -1;
+
+ if (bdev != bdev->bd_contains)
+ return bdev->bd_part->alignment_offset;
+
+ return q->limits.alignment_offset;
+}
+
+static inline int queue_discard_alignment(struct request_queue *q)
+{
+ if (q->limits.discard_misaligned)
+ return -1;
+
+ return q->limits.discard_alignment;
+}
+
+static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
+{
+ unsigned int alignment, granularity, offset;
+
+ if (!lim->max_discard_sectors)
+ return 0;
+
+ /* Why are these in bytes, not sectors? */
+ alignment = lim->discard_alignment >> SECTOR_SHIFT;
+ granularity = lim->discard_granularity >> SECTOR_SHIFT;
+ if (!granularity)
+ return 0;
+
+ /* Offset of the partition start in 'granularity' sectors */
+ offset = sector_div(sector, granularity);
+
+ /* And why do we do this modulus *again* in blkdev_issue_discard()? */
+ offset = (granularity + alignment - offset) % granularity;
+
+ /* Turn it back into bytes, gaah */
+ return offset << SECTOR_SHIFT;
+}
+
+static inline int bdev_discard_alignment(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (bdev != bdev->bd_contains)
+ return bdev->bd_part->discard_alignment;
+
+ return q->limits.discard_alignment;
+}
+
+static inline unsigned int bdev_write_same(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q)
+ return q->limits.max_write_same_sectors;
+
+ return 0;
+}
+
+static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q)
+ return q->limits.max_write_zeroes_sectors;
+
+ return 0;
+}
+
+static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q)
+ return blk_queue_zoned_model(q);
+
+ return BLK_ZONED_NONE;
+}
+
+static inline bool bdev_is_zoned(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q)
+ return blk_queue_is_zoned(q);
+
+ return false;
+}
+
+static inline unsigned int bdev_zone_sectors(struct block_device *bdev)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (q)
+ return blk_queue_zone_sectors(q);
+ return 0;
+}
+
+static inline int queue_dma_alignment(struct request_queue *q)
+{
+ return q ? q->dma_alignment : 511;
+}
+
+static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
+ unsigned int len)
+{
+ unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
+ return !(addr & alignment) && !(len & alignment);
+}
+
+/* assumes size > 256 */
+static inline unsigned int blksize_bits(unsigned int size)
+{
+ unsigned int bits = 8;
+ do {
+ bits++;
+ size >>= 1;
+ } while (size > 256);
+ return bits;
+}
+
+static inline unsigned int block_size(struct block_device *bdev)
+{
+ return bdev->bd_block_size;
+}
+
+static inline bool queue_flush_queueable(struct request_queue *q)
+{
+ return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
+}
+
+typedef struct {struct page *v;} Sector;
+
+unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
+
+static inline void put_dev_sector(Sector p)
+{
+ put_page(p.v);
+}
+
+static inline bool __bvec_gap_to_prev(struct request_queue *q,
+ struct bio_vec *bprv, unsigned int offset)
+{
+ return offset ||
+ ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
+}
+
+/*
+ * Check if adding a bio_vec after bprv with offset would create a gap in
+ * the SG list. Most drivers don't care about this, but some do.
+ */
+static inline bool bvec_gap_to_prev(struct request_queue *q,
+ struct bio_vec *bprv, unsigned int offset)
+{
+ if (!queue_virt_boundary(q))
+ return false;
+ return __bvec_gap_to_prev(q, bprv, offset);
+}
+
+/*
+ * Check if the two bvecs from two bios can be merged to one segment.
+ * If yes, no need to check gap between the two bios since the 1st bio
+ * and the 1st bvec in the 2nd bio can be handled in one segment.
+ */
+static inline bool bios_segs_mergeable(struct request_queue *q,
+ struct bio *prev, struct bio_vec *prev_last_bv,
+ struct bio_vec *next_first_bv)
+{
+ if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv))
+ return false;
+ if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
+ return false;
+ if (prev->bi_seg_back_size + next_first_bv->bv_len >
+ queue_max_segment_size(q))
+ return false;
+ return true;
+}
+
+static inline bool bio_will_gap(struct request_queue *q,
+ struct request *prev_rq,
+ struct bio *prev,
+ struct bio *next)
+{
+ if (bio_has_data(prev) && queue_virt_boundary(q)) {
+ struct bio_vec pb, nb;
+
+ /*
+ * don't merge if the 1st bio starts with non-zero
+ * offset, otherwise it is quite difficult to respect
+ * sg gap limit. We work hard to merge a huge number of small
+ * single bios in case of mkfs.
+ */
+ if (prev_rq)
+ bio_get_first_bvec(prev_rq->bio, &pb);
+ else
+ bio_get_first_bvec(prev, &pb);
+ if (pb.bv_offset)
+ return true;
+
+ /*
+ * We don't need to worry about the situation that the
+ * merged segment ends in unaligned virt boundary:
+ *
+ * - if 'pb' ends aligned, the merged segment ends aligned
+ * - if 'pb' ends unaligned, the next bio must include
+ * one single bvec of 'nb', otherwise the 'nb' can't
+ * merge with 'pb'
+ */
+ bio_get_last_bvec(prev, &pb);
+ bio_get_first_bvec(next, &nb);
+
+ if (!bios_segs_mergeable(q, prev, &pb, &nb))
+ return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
+ }
+
+ return false;
+}
+
+static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
+{
+ return bio_will_gap(req->q, req, req->biotail, bio);
+}
+
+static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
+{
+ return bio_will_gap(req->q, NULL, bio, req->bio);
+}
+
+int kblockd_schedule_work(struct work_struct *work);
+int kblockd_schedule_work_on(int cpu, struct work_struct *work);
+int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
+
+#define MODULE_ALIAS_BLOCKDEV(major,minor) \
+ MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
+#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
+ MODULE_ALIAS("block-major-" __stringify(major) "-*")
+
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+
+enum blk_integrity_flags {
+ BLK_INTEGRITY_VERIFY = 1 << 0,
+ BLK_INTEGRITY_GENERATE = 1 << 1,
+ BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
+ BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
+};
+
+struct blk_integrity_iter {
+ void *prot_buf;
+ void *data_buf;
+ sector_t seed;
+ unsigned int data_size;
+ unsigned short interval;
+ const char *disk_name;
+};
+
+typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
+
+struct blk_integrity_profile {
+ integrity_processing_fn *generate_fn;
+ integrity_processing_fn *verify_fn;
+ const char *name;
+};
+
+extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
+extern void blk_integrity_unregister(struct gendisk *);
+extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
+extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
+ struct scatterlist *);
+extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
+extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
+ struct request *);
+extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
+ struct bio *);
+
+static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
+{
+ struct blk_integrity *bi = &disk->queue->integrity;
+
+ if (!bi->profile)
+ return NULL;
+
+ return bi;
+}
+
+static inline
+struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
+{
+ return blk_get_integrity(bdev->bd_disk);
+}
+
+static inline bool blk_integrity_rq(struct request *rq)
+{
+ return rq->cmd_flags & REQ_INTEGRITY;
+}
+
+static inline void blk_queue_max_integrity_segments(struct request_queue *q,
+ unsigned int segs)
+{
+ q->limits.max_integrity_segments = segs;
+}
+
+static inline unsigned short
+queue_max_integrity_segments(struct request_queue *q)
+{
+ return q->limits.max_integrity_segments;
+}
+
+static inline bool integrity_req_gap_back_merge(struct request *req,
+ struct bio *next)
+{
+ struct bio_integrity_payload *bip = bio_integrity(req->bio);
+ struct bio_integrity_payload *bip_next = bio_integrity(next);
+
+ return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
+ bip_next->bip_vec[0].bv_offset);
+}
+
+static inline bool integrity_req_gap_front_merge(struct request *req,
+ struct bio *bio)
+{
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+ struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
+
+ return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
+ bip_next->bip_vec[0].bv_offset);
+}
+
+/**
+ * bio_integrity_intervals - Return number of integrity intervals for a bio
+ * @bi: blk_integrity profile for device
+ * @sectors: Size of the bio in 512-byte sectors
+ *
+ * Description: The block layer calculates everything in 512 byte
+ * sectors but integrity metadata is done in terms of the data integrity
+ * interval size of the storage device. Convert the block layer sectors
+ * to the appropriate number of integrity intervals.
+ */
+static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
+ unsigned int sectors)
+{
+ return sectors >> (bi->interval_exp - 9);
+}
+
+static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
+ unsigned int sectors)
+{
+ return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
+}
+
+#else /* CONFIG_BLK_DEV_INTEGRITY */
+
+struct bio;
+struct block_device;
+struct gendisk;
+struct blk_integrity;
+
+static inline int blk_integrity_rq(struct request *rq)
+{
+ return 0;
+}
+static inline int blk_rq_count_integrity_sg(struct request_queue *q,
+ struct bio *b)
+{
+ return 0;
+}
+static inline int blk_rq_map_integrity_sg(struct request_queue *q,
+ struct bio *b,
+ struct scatterlist *s)
+{
+ return 0;
+}
+static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
+{
+ return NULL;
+}
+static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
+{
+ return NULL;
+}
+static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
+{
+ return 0;
+}
+static inline void blk_integrity_register(struct gendisk *d,
+ struct blk_integrity *b)
+{
+}
+static inline void blk_integrity_unregister(struct gendisk *d)
+{
+}
+static inline void blk_queue_max_integrity_segments(struct request_queue *q,
+ unsigned int segs)
+{
+}
+static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
+{
+ return 0;
+}
+static inline bool blk_integrity_merge_rq(struct request_queue *rq,
+ struct request *r1,
+ struct request *r2)
+{
+ return true;
+}
+static inline bool blk_integrity_merge_bio(struct request_queue *rq,
+ struct request *r,
+ struct bio *b)
+{
+ return true;
+}
+
+static inline bool integrity_req_gap_back_merge(struct request *req,
+ struct bio *next)
+{
+ return false;
+}
+static inline bool integrity_req_gap_front_merge(struct request *req,
+ struct bio *bio)
+{
+ return false;
+}
+
+static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
+ unsigned int sectors)
+{
+ return 0;
+}
+
+static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
+ unsigned int sectors)
+{
+ return 0;
+}
+
+#endif /* CONFIG_BLK_DEV_INTEGRITY */
+
+struct block_device_operations {
+ int (*open) (struct block_device *, fmode_t);
+ void (*release) (struct gendisk *, fmode_t);
+ int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
+ int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
+ int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
+ unsigned int (*check_events) (struct gendisk *disk,
+ unsigned int clearing);
+ /* ->media_changed() is DEPRECATED, use ->check_events() instead */
+ int (*media_changed) (struct gendisk *);
+ void (*unlock_native_capacity) (struct gendisk *);
+ int (*revalidate_disk) (struct gendisk *);
+ int (*getgeo)(struct block_device *, struct hd_geometry *);
+ /* this callback is with swap_lock and sometimes page table lock held */
+ void (*swap_slot_free_notify) (struct block_device *, unsigned long);
+ struct module *owner;
+ const struct pr_ops *pr_ops;
+};
+
+extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
+ unsigned long);
+extern int bdev_read_page(struct block_device *, sector_t, struct page *);
+extern int bdev_write_page(struct block_device *, sector_t, struct page *,
+ struct writeback_control *);
+
+#ifdef CONFIG_BLK_DEV_ZONED
+bool blk_req_needs_zone_write_lock(struct request *rq);
+void __blk_req_zone_write_lock(struct request *rq);
+void __blk_req_zone_write_unlock(struct request *rq);
+
+static inline void blk_req_zone_write_lock(struct request *rq)
+{
+ if (blk_req_needs_zone_write_lock(rq))
+ __blk_req_zone_write_lock(rq);
+}
+
+static inline void blk_req_zone_write_unlock(struct request *rq)
+{
+ if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
+ __blk_req_zone_write_unlock(rq);
+}
+
+static inline bool blk_req_zone_is_write_locked(struct request *rq)
+{
+ return rq->q->seq_zones_wlock &&
+ test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
+}
+
+static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
+{
+ if (!blk_req_needs_zone_write_lock(rq))
+ return true;
+ return !blk_req_zone_is_write_locked(rq);
+}
+#else
+static inline bool blk_req_needs_zone_write_lock(struct request *rq)
+{
+ return false;
+}
+
+static inline void blk_req_zone_write_lock(struct request *rq)
+{
+}
+
+static inline void blk_req_zone_write_unlock(struct request *rq)
+{
+}
+static inline bool blk_req_zone_is_write_locked(struct request *rq)
+{
+ return false;
+}
+
+static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
+{
+ return true;
+}
+#endif /* CONFIG_BLK_DEV_ZONED */
+
+#else /* CONFIG_BLOCK */
+
+struct block_device;
+
+/*
+ * stubs for when the block layer is configured out
+ */
+#define buffer_heads_over_limit 0
+
+static inline long nr_blockdev_pages(void)
+{
+ return 0;
+}
+
+struct blk_plug {
+};
+
+static inline void blk_start_plug(struct blk_plug *plug)
+{
+}
+
+static inline void blk_finish_plug(struct blk_plug *plug)
+{
+}
+
+static inline void blk_flush_plug(struct task_struct *task)
+{
+}
+
+static inline void blk_schedule_flush_plug(struct task_struct *task)
+{
+}
+
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+ return false;
+}
+
+static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
+ sector_t *error_sector)
+{
+ return 0;
+}
+
+#endif /* CONFIG_BLOCK */
+
+#endif