v4.19.13 snapshot.
diff --git a/include/linux/fs.h b/include/linux/fs.h
new file mode 100644
index 0000000..7b60848
--- /dev/null
+++ b/include/linux/fs.h
@@ -0,0 +1,3459 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_FS_H
+#define _LINUX_FS_H
+
+#include <linux/linkage.h>
+#include <linux/wait_bit.h>
+#include <linux/kdev_t.h>
+#include <linux/dcache.h>
+#include <linux/path.h>
+#include <linux/stat.h>
+#include <linux/cache.h>
+#include <linux/list.h>
+#include <linux/list_lru.h>
+#include <linux/llist.h>
+#include <linux/radix-tree.h>
+#include <linux/xarray.h>
+#include <linux/rbtree.h>
+#include <linux/init.h>
+#include <linux/pid.h>
+#include <linux/bug.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/mm_types.h>
+#include <linux/capability.h>
+#include <linux/semaphore.h>
+#include <linux/fcntl.h>
+#include <linux/fiemap.h>
+#include <linux/rculist_bl.h>
+#include <linux/atomic.h>
+#include <linux/shrinker.h>
+#include <linux/migrate_mode.h>
+#include <linux/uidgid.h>
+#include <linux/lockdep.h>
+#include <linux/percpu-rwsem.h>
+#include <linux/workqueue.h>
+#include <linux/delayed_call.h>
+#include <linux/uuid.h>
+#include <linux/errseq.h>
+#include <linux/ioprio.h>
+
+#include <asm/byteorder.h>
+#include <uapi/linux/fs.h>
+
+struct backing_dev_info;
+struct bdi_writeback;
+struct bio;
+struct export_operations;
+struct hd_geometry;
+struct iovec;
+struct kiocb;
+struct kobject;
+struct pipe_inode_info;
+struct poll_table_struct;
+struct kstatfs;
+struct vm_area_struct;
+struct vfsmount;
+struct cred;
+struct swap_info_struct;
+struct seq_file;
+struct workqueue_struct;
+struct iov_iter;
+struct fscrypt_info;
+struct fscrypt_operations;
+
+extern void __init inode_init(void);
+extern void __init inode_init_early(void);
+extern void __init files_init(void);
+extern void __init files_maxfiles_init(void);
+
+extern struct files_stat_struct files_stat;
+extern unsigned long get_max_files(void);
+extern unsigned int sysctl_nr_open;
+extern struct inodes_stat_t inodes_stat;
+extern int leases_enable, lease_break_time;
+extern int sysctl_protected_symlinks;
+extern int sysctl_protected_hardlinks;
+extern int sysctl_protected_fifos;
+extern int sysctl_protected_regular;
+
+typedef __kernel_rwf_t rwf_t;
+
+struct buffer_head;
+typedef int (get_block_t)(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create);
+typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
+ ssize_t bytes, void *private);
+
+#define MAY_EXEC 0x00000001
+#define MAY_WRITE 0x00000002
+#define MAY_READ 0x00000004
+#define MAY_APPEND 0x00000008
+#define MAY_ACCESS 0x00000010
+#define MAY_OPEN 0x00000020
+#define MAY_CHDIR 0x00000040
+/* called from RCU mode, don't block */
+#define MAY_NOT_BLOCK 0x00000080
+
+/*
+ * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
+ * to O_WRONLY and O_RDWR via the strange trick in do_dentry_open()
+ */
+
+/* file is open for reading */
+#define FMODE_READ ((__force fmode_t)0x1)
+/* file is open for writing */
+#define FMODE_WRITE ((__force fmode_t)0x2)
+/* file is seekable */
+#define FMODE_LSEEK ((__force fmode_t)0x4)
+/* file can be accessed using pread */
+#define FMODE_PREAD ((__force fmode_t)0x8)
+/* file can be accessed using pwrite */
+#define FMODE_PWRITE ((__force fmode_t)0x10)
+/* File is opened for execution with sys_execve / sys_uselib */
+#define FMODE_EXEC ((__force fmode_t)0x20)
+/* File is opened with O_NDELAY (only set for block devices) */
+#define FMODE_NDELAY ((__force fmode_t)0x40)
+/* File is opened with O_EXCL (only set for block devices) */
+#define FMODE_EXCL ((__force fmode_t)0x80)
+/* File is opened using open(.., 3, ..) and is writeable only for ioctls
+ (specialy hack for floppy.c) */
+#define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
+/* 32bit hashes as llseek() offset (for directories) */
+#define FMODE_32BITHASH ((__force fmode_t)0x200)
+/* 64bit hashes as llseek() offset (for directories) */
+#define FMODE_64BITHASH ((__force fmode_t)0x400)
+
+/*
+ * Don't update ctime and mtime.
+ *
+ * Currently a special hack for the XFS open_by_handle ioctl, but we'll
+ * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
+ */
+#define FMODE_NOCMTIME ((__force fmode_t)0x800)
+
+/* Expect random access pattern */
+#define FMODE_RANDOM ((__force fmode_t)0x1000)
+
+/* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
+#define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
+
+/* File is opened with O_PATH; almost nothing can be done with it */
+#define FMODE_PATH ((__force fmode_t)0x4000)
+
+/* File needs atomic accesses to f_pos */
+#define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
+/* Write access to underlying fs */
+#define FMODE_WRITER ((__force fmode_t)0x10000)
+/* Has read method(s) */
+#define FMODE_CAN_READ ((__force fmode_t)0x20000)
+/* Has write method(s) */
+#define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
+
+#define FMODE_OPENED ((__force fmode_t)0x80000)
+#define FMODE_CREATED ((__force fmode_t)0x100000)
+
+/* File was opened by fanotify and shouldn't generate fanotify events */
+#define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
+
+/* File is capable of returning -EAGAIN if I/O will block */
+#define FMODE_NOWAIT ((__force fmode_t)0x8000000)
+
+/* File does not contribute to nr_files count */
+#define FMODE_NOACCOUNT ((__force fmode_t)0x20000000)
+
+/*
+ * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
+ * that indicates that they should check the contents of the iovec are
+ * valid, but not check the memory that the iovec elements
+ * points too.
+ */
+#define CHECK_IOVEC_ONLY -1
+
+/*
+ * Attribute flags. These should be or-ed together to figure out what
+ * has been changed!
+ */
+#define ATTR_MODE (1 << 0)
+#define ATTR_UID (1 << 1)
+#define ATTR_GID (1 << 2)
+#define ATTR_SIZE (1 << 3)
+#define ATTR_ATIME (1 << 4)
+#define ATTR_MTIME (1 << 5)
+#define ATTR_CTIME (1 << 6)
+#define ATTR_ATIME_SET (1 << 7)
+#define ATTR_MTIME_SET (1 << 8)
+#define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
+#define ATTR_KILL_SUID (1 << 11)
+#define ATTR_KILL_SGID (1 << 12)
+#define ATTR_FILE (1 << 13)
+#define ATTR_KILL_PRIV (1 << 14)
+#define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
+#define ATTR_TIMES_SET (1 << 16)
+#define ATTR_TOUCH (1 << 17)
+
+/*
+ * Whiteout is represented by a char device. The following constants define the
+ * mode and device number to use.
+ */
+#define WHITEOUT_MODE 0
+#define WHITEOUT_DEV 0
+
+/*
+ * This is the Inode Attributes structure, used for notify_change(). It
+ * uses the above definitions as flags, to know which values have changed.
+ * Also, in this manner, a Filesystem can look at only the values it cares
+ * about. Basically, these are the attributes that the VFS layer can
+ * request to change from the FS layer.
+ *
+ * Derek Atkins <warlord@MIT.EDU> 94-10-20
+ */
+struct iattr {
+ unsigned int ia_valid;
+ umode_t ia_mode;
+ kuid_t ia_uid;
+ kgid_t ia_gid;
+ loff_t ia_size;
+ struct timespec64 ia_atime;
+ struct timespec64 ia_mtime;
+ struct timespec64 ia_ctime;
+
+ /*
+ * Not an attribute, but an auxiliary info for filesystems wanting to
+ * implement an ftruncate() like method. NOTE: filesystem should
+ * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
+ */
+ struct file *ia_file;
+};
+
+/*
+ * Includes for diskquotas.
+ */
+#include <linux/quota.h>
+
+/*
+ * Maximum number of layers of fs stack. Needs to be limited to
+ * prevent kernel stack overflow
+ */
+#define FILESYSTEM_MAX_STACK_DEPTH 2
+
+/**
+ * enum positive_aop_returns - aop return codes with specific semantics
+ *
+ * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
+ * completed, that the page is still locked, and
+ * should be considered active. The VM uses this hint
+ * to return the page to the active list -- it won't
+ * be a candidate for writeback again in the near
+ * future. Other callers must be careful to unlock
+ * the page if they get this return. Returned by
+ * writepage();
+ *
+ * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
+ * unlocked it and the page might have been truncated.
+ * The caller should back up to acquiring a new page and
+ * trying again. The aop will be taking reasonable
+ * precautions not to livelock. If the caller held a page
+ * reference, it should drop it before retrying. Returned
+ * by readpage().
+ *
+ * address_space_operation functions return these large constants to indicate
+ * special semantics to the caller. These are much larger than the bytes in a
+ * page to allow for functions that return the number of bytes operated on in a
+ * given page.
+ */
+
+enum positive_aop_returns {
+ AOP_WRITEPAGE_ACTIVATE = 0x80000,
+ AOP_TRUNCATED_PAGE = 0x80001,
+};
+
+#define AOP_FLAG_CONT_EXPAND 0x0001 /* called from cont_expand */
+#define AOP_FLAG_NOFS 0x0002 /* used by filesystem to direct
+ * helper code (eg buffer layer)
+ * to clear GFP_FS from alloc */
+
+/*
+ * oh the beauties of C type declarations.
+ */
+struct page;
+struct address_space;
+struct writeback_control;
+
+/*
+ * Write life time hint values.
+ * Stored in struct inode as u8.
+ */
+enum rw_hint {
+ WRITE_LIFE_NOT_SET = 0,
+ WRITE_LIFE_NONE = RWH_WRITE_LIFE_NONE,
+ WRITE_LIFE_SHORT = RWH_WRITE_LIFE_SHORT,
+ WRITE_LIFE_MEDIUM = RWH_WRITE_LIFE_MEDIUM,
+ WRITE_LIFE_LONG = RWH_WRITE_LIFE_LONG,
+ WRITE_LIFE_EXTREME = RWH_WRITE_LIFE_EXTREME,
+};
+
+#define IOCB_EVENTFD (1 << 0)
+#define IOCB_APPEND (1 << 1)
+#define IOCB_DIRECT (1 << 2)
+#define IOCB_HIPRI (1 << 3)
+#define IOCB_DSYNC (1 << 4)
+#define IOCB_SYNC (1 << 5)
+#define IOCB_WRITE (1 << 6)
+#define IOCB_NOWAIT (1 << 7)
+
+struct kiocb {
+ struct file *ki_filp;
+ loff_t ki_pos;
+ void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
+ void *private;
+ int ki_flags;
+ u16 ki_hint;
+ u16 ki_ioprio; /* See linux/ioprio.h */
+} __randomize_layout;
+
+static inline bool is_sync_kiocb(struct kiocb *kiocb)
+{
+ return kiocb->ki_complete == NULL;
+}
+
+/*
+ * "descriptor" for what we're up to with a read.
+ * This allows us to use the same read code yet
+ * have multiple different users of the data that
+ * we read from a file.
+ *
+ * The simplest case just copies the data to user
+ * mode.
+ */
+typedef struct {
+ size_t written;
+ size_t count;
+ union {
+ char __user *buf;
+ void *data;
+ } arg;
+ int error;
+} read_descriptor_t;
+
+typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
+ unsigned long, unsigned long);
+
+struct address_space_operations {
+ int (*writepage)(struct page *page, struct writeback_control *wbc);
+ int (*readpage)(struct file *, struct page *);
+
+ /* Write back some dirty pages from this mapping. */
+ int (*writepages)(struct address_space *, struct writeback_control *);
+
+ /* Set a page dirty. Return true if this dirtied it */
+ int (*set_page_dirty)(struct page *page);
+
+ /*
+ * Reads in the requested pages. Unlike ->readpage(), this is
+ * PURELY used for read-ahead!.
+ */
+ int (*readpages)(struct file *filp, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages);
+
+ int (*write_begin)(struct file *, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata);
+ int (*write_end)(struct file *, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata);
+
+ /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
+ sector_t (*bmap)(struct address_space *, sector_t);
+ void (*invalidatepage) (struct page *, unsigned int, unsigned int);
+ int (*releasepage) (struct page *, gfp_t);
+ void (*freepage)(struct page *);
+ ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
+ /*
+ * migrate the contents of a page to the specified target. If
+ * migrate_mode is MIGRATE_ASYNC, it must not block.
+ */
+ int (*migratepage) (struct address_space *,
+ struct page *, struct page *, enum migrate_mode);
+ bool (*isolate_page)(struct page *, isolate_mode_t);
+ void (*putback_page)(struct page *);
+ int (*launder_page) (struct page *);
+ int (*is_partially_uptodate) (struct page *, unsigned long,
+ unsigned long);
+ void (*is_dirty_writeback) (struct page *, bool *, bool *);
+ int (*error_remove_page)(struct address_space *, struct page *);
+
+ /* swapfile support */
+ int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
+ sector_t *span);
+ void (*swap_deactivate)(struct file *file);
+};
+
+extern const struct address_space_operations empty_aops;
+
+/*
+ * pagecache_write_begin/pagecache_write_end must be used by general code
+ * to write into the pagecache.
+ */
+int pagecache_write_begin(struct file *, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata);
+
+int pagecache_write_end(struct file *, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata);
+
+struct address_space {
+ struct inode *host; /* owner: inode, block_device */
+ struct radix_tree_root i_pages; /* cached pages */
+ atomic_t i_mmap_writable;/* count VM_SHARED mappings */
+ struct rb_root_cached i_mmap; /* tree of private and shared mappings */
+ struct rw_semaphore i_mmap_rwsem; /* protect tree, count, list */
+ /* Protected by the i_pages lock */
+ unsigned long nrpages; /* number of total pages */
+ /* number of shadow or DAX exceptional entries */
+ unsigned long nrexceptional;
+ pgoff_t writeback_index;/* writeback starts here */
+ const struct address_space_operations *a_ops; /* methods */
+ unsigned long flags; /* error bits */
+ spinlock_t private_lock; /* for use by the address_space */
+ gfp_t gfp_mask; /* implicit gfp mask for allocations */
+ struct list_head private_list; /* for use by the address_space */
+ void *private_data; /* ditto */
+ errseq_t wb_err;
+} __attribute__((aligned(sizeof(long)))) __randomize_layout;
+ /*
+ * On most architectures that alignment is already the case; but
+ * must be enforced here for CRIS, to let the least significant bit
+ * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
+ */
+struct request_queue;
+
+struct block_device {
+ dev_t bd_dev; /* not a kdev_t - it's a search key */
+ int bd_openers;
+ struct inode * bd_inode; /* will die */
+ struct super_block * bd_super;
+ struct mutex bd_mutex; /* open/close mutex */
+ void * bd_claiming;
+ void * bd_holder;
+ int bd_holders;
+ bool bd_write_holder;
+#ifdef CONFIG_SYSFS
+ struct list_head bd_holder_disks;
+#endif
+ struct block_device * bd_contains;
+ unsigned bd_block_size;
+ u8 bd_partno;
+ struct hd_struct * bd_part;
+ /* number of times partitions within this device have been opened. */
+ unsigned bd_part_count;
+ int bd_invalidated;
+ struct gendisk * bd_disk;
+ struct request_queue * bd_queue;
+ struct backing_dev_info *bd_bdi;
+ struct list_head bd_list;
+ /*
+ * Private data. You must have bd_claim'ed the block_device
+ * to use this. NOTE: bd_claim allows an owner to claim
+ * the same device multiple times, the owner must take special
+ * care to not mess up bd_private for that case.
+ */
+ unsigned long bd_private;
+
+ /* The counter of freeze processes */
+ int bd_fsfreeze_count;
+ /* Mutex for freeze */
+ struct mutex bd_fsfreeze_mutex;
+} __randomize_layout;
+
+/*
+ * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
+ * radix trees
+ */
+#define PAGECACHE_TAG_DIRTY 0
+#define PAGECACHE_TAG_WRITEBACK 1
+#define PAGECACHE_TAG_TOWRITE 2
+
+int mapping_tagged(struct address_space *mapping, int tag);
+
+static inline void i_mmap_lock_write(struct address_space *mapping)
+{
+ down_write(&mapping->i_mmap_rwsem);
+}
+
+static inline void i_mmap_unlock_write(struct address_space *mapping)
+{
+ up_write(&mapping->i_mmap_rwsem);
+}
+
+static inline void i_mmap_lock_read(struct address_space *mapping)
+{
+ down_read(&mapping->i_mmap_rwsem);
+}
+
+static inline void i_mmap_unlock_read(struct address_space *mapping)
+{
+ up_read(&mapping->i_mmap_rwsem);
+}
+
+/*
+ * Might pages of this file be mapped into userspace?
+ */
+static inline int mapping_mapped(struct address_space *mapping)
+{
+ return !RB_EMPTY_ROOT(&mapping->i_mmap.rb_root);
+}
+
+/*
+ * Might pages of this file have been modified in userspace?
+ * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
+ * marks vma as VM_SHARED if it is shared, and the file was opened for
+ * writing i.e. vma may be mprotected writable even if now readonly.
+ *
+ * If i_mmap_writable is negative, no new writable mappings are allowed. You
+ * can only deny writable mappings, if none exists right now.
+ */
+static inline int mapping_writably_mapped(struct address_space *mapping)
+{
+ return atomic_read(&mapping->i_mmap_writable) > 0;
+}
+
+static inline int mapping_map_writable(struct address_space *mapping)
+{
+ return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
+ 0 : -EPERM;
+}
+
+static inline void mapping_unmap_writable(struct address_space *mapping)
+{
+ atomic_dec(&mapping->i_mmap_writable);
+}
+
+static inline int mapping_deny_writable(struct address_space *mapping)
+{
+ return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
+ 0 : -EBUSY;
+}
+
+static inline void mapping_allow_writable(struct address_space *mapping)
+{
+ atomic_inc(&mapping->i_mmap_writable);
+}
+
+/*
+ * Use sequence counter to get consistent i_size on 32-bit processors.
+ */
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#include <linux/seqlock.h>
+#define __NEED_I_SIZE_ORDERED
+#define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
+#else
+#define i_size_ordered_init(inode) do { } while (0)
+#endif
+
+struct posix_acl;
+#define ACL_NOT_CACHED ((void *)(-1))
+#define ACL_DONT_CACHE ((void *)(-3))
+
+static inline struct posix_acl *
+uncached_acl_sentinel(struct task_struct *task)
+{
+ return (void *)task + 1;
+}
+
+static inline bool
+is_uncached_acl(struct posix_acl *acl)
+{
+ return (long)acl & 1;
+}
+
+#define IOP_FASTPERM 0x0001
+#define IOP_LOOKUP 0x0002
+#define IOP_NOFOLLOW 0x0004
+#define IOP_XATTR 0x0008
+#define IOP_DEFAULT_READLINK 0x0010
+
+struct fsnotify_mark_connector;
+
+/*
+ * Keep mostly read-only and often accessed (especially for
+ * the RCU path lookup and 'stat' data) fields at the beginning
+ * of the 'struct inode'
+ */
+struct inode {
+ umode_t i_mode;
+ unsigned short i_opflags;
+ kuid_t i_uid;
+ kgid_t i_gid;
+ unsigned int i_flags;
+
+#ifdef CONFIG_FS_POSIX_ACL
+ struct posix_acl *i_acl;
+ struct posix_acl *i_default_acl;
+#endif
+
+ const struct inode_operations *i_op;
+ struct super_block *i_sb;
+ struct address_space *i_mapping;
+
+#ifdef CONFIG_SECURITY
+ void *i_security;
+#endif
+
+ /* Stat data, not accessed from path walking */
+ unsigned long i_ino;
+ /*
+ * Filesystems may only read i_nlink directly. They shall use the
+ * following functions for modification:
+ *
+ * (set|clear|inc|drop)_nlink
+ * inode_(inc|dec)_link_count
+ */
+ union {
+ const unsigned int i_nlink;
+ unsigned int __i_nlink;
+ };
+ dev_t i_rdev;
+ loff_t i_size;
+ struct timespec64 i_atime;
+ struct timespec64 i_mtime;
+ struct timespec64 i_ctime;
+ spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
+ unsigned short i_bytes;
+ u8 i_blkbits;
+ u8 i_write_hint;
+ blkcnt_t i_blocks;
+
+#ifdef __NEED_I_SIZE_ORDERED
+ seqcount_t i_size_seqcount;
+#endif
+
+ /* Misc */
+ unsigned long i_state;
+ struct rw_semaphore i_rwsem;
+
+ unsigned long dirtied_when; /* jiffies of first dirtying */
+ unsigned long dirtied_time_when;
+
+ struct hlist_node i_hash;
+ struct list_head i_io_list; /* backing dev IO list */
+#ifdef CONFIG_CGROUP_WRITEBACK
+ struct bdi_writeback *i_wb; /* the associated cgroup wb */
+
+ /* foreign inode detection, see wbc_detach_inode() */
+ int i_wb_frn_winner;
+ u16 i_wb_frn_avg_time;
+ u16 i_wb_frn_history;
+#endif
+ struct list_head i_lru; /* inode LRU list */
+ struct list_head i_sb_list;
+ struct list_head i_wb_list; /* backing dev writeback list */
+ union {
+ struct hlist_head i_dentry;
+ struct rcu_head i_rcu;
+ };
+ atomic64_t i_version;
+ atomic_t i_count;
+ atomic_t i_dio_count;
+ atomic_t i_writecount;
+#ifdef CONFIG_IMA
+ atomic_t i_readcount; /* struct files open RO */
+#endif
+ const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
+ struct file_lock_context *i_flctx;
+ struct address_space i_data;
+ struct list_head i_devices;
+ union {
+ struct pipe_inode_info *i_pipe;
+ struct block_device *i_bdev;
+ struct cdev *i_cdev;
+ char *i_link;
+ unsigned i_dir_seq;
+ };
+
+ __u32 i_generation;
+
+#ifdef CONFIG_FSNOTIFY
+ __u32 i_fsnotify_mask; /* all events this inode cares about */
+ struct fsnotify_mark_connector __rcu *i_fsnotify_marks;
+#endif
+
+#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ struct fscrypt_info *i_crypt_info;
+#endif
+
+ void *i_private; /* fs or device private pointer */
+} __randomize_layout;
+
+static inline unsigned int i_blocksize(const struct inode *node)
+{
+ return (1 << node->i_blkbits);
+}
+
+static inline int inode_unhashed(struct inode *inode)
+{
+ return hlist_unhashed(&inode->i_hash);
+}
+
+/*
+ * __mark_inode_dirty expects inodes to be hashed. Since we don't
+ * want special inodes in the fileset inode space, we make them
+ * appear hashed, but do not put on any lists. hlist_del()
+ * will work fine and require no locking.
+ */
+static inline void inode_fake_hash(struct inode *inode)
+{
+ hlist_add_fake(&inode->i_hash);
+}
+
+/*
+ * inode->i_mutex nesting subclasses for the lock validator:
+ *
+ * 0: the object of the current VFS operation
+ * 1: parent
+ * 2: child/target
+ * 3: xattr
+ * 4: second non-directory
+ * 5: second parent (when locking independent directories in rename)
+ *
+ * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
+ * non-directories at once.
+ *
+ * The locking order between these classes is
+ * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
+ */
+enum inode_i_mutex_lock_class
+{
+ I_MUTEX_NORMAL,
+ I_MUTEX_PARENT,
+ I_MUTEX_CHILD,
+ I_MUTEX_XATTR,
+ I_MUTEX_NONDIR2,
+ I_MUTEX_PARENT2,
+};
+
+static inline void inode_lock(struct inode *inode)
+{
+ down_write(&inode->i_rwsem);
+}
+
+static inline void inode_unlock(struct inode *inode)
+{
+ up_write(&inode->i_rwsem);
+}
+
+static inline void inode_lock_shared(struct inode *inode)
+{
+ down_read(&inode->i_rwsem);
+}
+
+static inline void inode_unlock_shared(struct inode *inode)
+{
+ up_read(&inode->i_rwsem);
+}
+
+static inline int inode_trylock(struct inode *inode)
+{
+ return down_write_trylock(&inode->i_rwsem);
+}
+
+static inline int inode_trylock_shared(struct inode *inode)
+{
+ return down_read_trylock(&inode->i_rwsem);
+}
+
+static inline int inode_is_locked(struct inode *inode)
+{
+ return rwsem_is_locked(&inode->i_rwsem);
+}
+
+static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
+{
+ down_write_nested(&inode->i_rwsem, subclass);
+}
+
+static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass)
+{
+ down_read_nested(&inode->i_rwsem, subclass);
+}
+
+void lock_two_nondirectories(struct inode *, struct inode*);
+void unlock_two_nondirectories(struct inode *, struct inode*);
+
+/*
+ * NOTE: in a 32bit arch with a preemptable kernel and
+ * an UP compile the i_size_read/write must be atomic
+ * with respect to the local cpu (unlike with preempt disabled),
+ * but they don't need to be atomic with respect to other cpus like in
+ * true SMP (so they need either to either locally disable irq around
+ * the read or for example on x86 they can be still implemented as a
+ * cmpxchg8b without the need of the lock prefix). For SMP compiles
+ * and 64bit archs it makes no difference if preempt is enabled or not.
+ */
+static inline loff_t i_size_read(const struct inode *inode)
+{
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+ loff_t i_size;
+ unsigned int seq;
+
+ do {
+ seq = read_seqcount_begin(&inode->i_size_seqcount);
+ i_size = inode->i_size;
+ } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
+ return i_size;
+#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
+ loff_t i_size;
+
+ preempt_disable();
+ i_size = inode->i_size;
+ preempt_enable();
+ return i_size;
+#else
+ return inode->i_size;
+#endif
+}
+
+/*
+ * NOTE: unlike i_size_read(), i_size_write() does need locking around it
+ * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
+ * can be lost, resulting in subsequent i_size_read() calls spinning forever.
+ */
+static inline void i_size_write(struct inode *inode, loff_t i_size)
+{
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+ preempt_disable();
+ write_seqcount_begin(&inode->i_size_seqcount);
+ inode->i_size = i_size;
+ write_seqcount_end(&inode->i_size_seqcount);
+ preempt_enable();
+#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
+ preempt_disable();
+ inode->i_size = i_size;
+ preempt_enable();
+#else
+ inode->i_size = i_size;
+#endif
+}
+
+static inline unsigned iminor(const struct inode *inode)
+{
+ return MINOR(inode->i_rdev);
+}
+
+static inline unsigned imajor(const struct inode *inode)
+{
+ return MAJOR(inode->i_rdev);
+}
+
+extern struct block_device *I_BDEV(struct inode *inode);
+
+struct fown_struct {
+ rwlock_t lock; /* protects pid, uid, euid fields */
+ struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
+ enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
+ kuid_t uid, euid; /* uid/euid of process setting the owner */
+ int signum; /* posix.1b rt signal to be delivered on IO */
+};
+
+/*
+ * Track a single file's readahead state
+ */
+struct file_ra_state {
+ pgoff_t start; /* where readahead started */
+ unsigned int size; /* # of readahead pages */
+ unsigned int async_size; /* do asynchronous readahead when
+ there are only # of pages ahead */
+
+ unsigned int ra_pages; /* Maximum readahead window */
+ unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
+ loff_t prev_pos; /* Cache last read() position */
+};
+
+/*
+ * Check if @index falls in the readahead windows.
+ */
+static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
+{
+ return (index >= ra->start &&
+ index < ra->start + ra->size);
+}
+
+struct file {
+ union {
+ struct llist_node fu_llist;
+ struct rcu_head fu_rcuhead;
+ } f_u;
+ struct path f_path;
+ struct inode *f_inode; /* cached value */
+ const struct file_operations *f_op;
+
+ /*
+ * Protects f_ep_links, f_flags.
+ * Must not be taken from IRQ context.
+ */
+ spinlock_t f_lock;
+ enum rw_hint f_write_hint;
+ atomic_long_t f_count;
+ unsigned int f_flags;
+ fmode_t f_mode;
+ struct mutex f_pos_lock;
+ loff_t f_pos;
+ struct fown_struct f_owner;
+ const struct cred *f_cred;
+ struct file_ra_state f_ra;
+
+ u64 f_version;
+#ifdef CONFIG_SECURITY
+ void *f_security;
+#endif
+ /* needed for tty driver, and maybe others */
+ void *private_data;
+
+#ifdef CONFIG_EPOLL
+ /* Used by fs/eventpoll.c to link all the hooks to this file */
+ struct list_head f_ep_links;
+ struct list_head f_tfile_llink;
+#endif /* #ifdef CONFIG_EPOLL */
+ struct address_space *f_mapping;
+ errseq_t f_wb_err;
+} __randomize_layout
+ __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
+
+struct file_handle {
+ __u32 handle_bytes;
+ int handle_type;
+ /* file identifier */
+ unsigned char f_handle[0];
+};
+
+static inline struct file *get_file(struct file *f)
+{
+ atomic_long_inc(&f->f_count);
+ return f;
+}
+#define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
+#define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
+#define file_count(x) atomic_long_read(&(x)->f_count)
+
+#define MAX_NON_LFS ((1UL<<31) - 1)
+
+/* Page cache limit. The filesystems should put that into their s_maxbytes
+ limits, otherwise bad things can happen in VM. */
+#if BITS_PER_LONG==32
+#define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
+#elif BITS_PER_LONG==64
+#define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
+#endif
+
+#define FL_POSIX 1
+#define FL_FLOCK 2
+#define FL_DELEG 4 /* NFSv4 delegation */
+#define FL_ACCESS 8 /* not trying to lock, just looking */
+#define FL_EXISTS 16 /* when unlocking, test for existence */
+#define FL_LEASE 32 /* lease held on this file */
+#define FL_CLOSE 64 /* unlock on close */
+#define FL_SLEEP 128 /* A blocking lock */
+#define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
+#define FL_UNLOCK_PENDING 512 /* Lease is being broken */
+#define FL_OFDLCK 1024 /* lock is "owned" by struct file */
+#define FL_LAYOUT 2048 /* outstanding pNFS layout */
+
+#define FL_CLOSE_POSIX (FL_POSIX | FL_CLOSE)
+
+/*
+ * Special return value from posix_lock_file() and vfs_lock_file() for
+ * asynchronous locking.
+ */
+#define FILE_LOCK_DEFERRED 1
+
+/* legacy typedef, should eventually be removed */
+typedef void *fl_owner_t;
+
+struct file_lock;
+
+struct file_lock_operations {
+ void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
+ void (*fl_release_private)(struct file_lock *);
+};
+
+struct lock_manager_operations {
+ int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
+ unsigned long (*lm_owner_key)(struct file_lock *);
+ fl_owner_t (*lm_get_owner)(fl_owner_t);
+ void (*lm_put_owner)(fl_owner_t);
+ void (*lm_notify)(struct file_lock *); /* unblock callback */
+ int (*lm_grant)(struct file_lock *, int);
+ bool (*lm_break)(struct file_lock *);
+ int (*lm_change)(struct file_lock *, int, struct list_head *);
+ void (*lm_setup)(struct file_lock *, void **);
+};
+
+struct lock_manager {
+ struct list_head list;
+ /*
+ * NFSv4 and up also want opens blocked during the grace period;
+ * NLM doesn't care:
+ */
+ bool block_opens;
+};
+
+struct net;
+void locks_start_grace(struct net *, struct lock_manager *);
+void locks_end_grace(struct lock_manager *);
+bool locks_in_grace(struct net *);
+bool opens_in_grace(struct net *);
+
+/* that will die - we need it for nfs_lock_info */
+#include <linux/nfs_fs_i.h>
+
+/*
+ * struct file_lock represents a generic "file lock". It's used to represent
+ * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
+ * note that the same struct is used to represent both a request for a lock and
+ * the lock itself, but the same object is never used for both.
+ *
+ * FIXME: should we create a separate "struct lock_request" to help distinguish
+ * these two uses?
+ *
+ * The varous i_flctx lists are ordered by:
+ *
+ * 1) lock owner
+ * 2) lock range start
+ * 3) lock range end
+ *
+ * Obviously, the last two criteria only matter for POSIX locks.
+ */
+struct file_lock {
+ struct file_lock *fl_next; /* singly linked list for this inode */
+ struct list_head fl_list; /* link into file_lock_context */
+ struct hlist_node fl_link; /* node in global lists */
+ struct list_head fl_block; /* circular list of blocked processes */
+ fl_owner_t fl_owner;
+ unsigned int fl_flags;
+ unsigned char fl_type;
+ unsigned int fl_pid;
+ int fl_link_cpu; /* what cpu's list is this on? */
+ wait_queue_head_t fl_wait;
+ struct file *fl_file;
+ loff_t fl_start;
+ loff_t fl_end;
+
+ struct fasync_struct * fl_fasync; /* for lease break notifications */
+ /* for lease breaks: */
+ unsigned long fl_break_time;
+ unsigned long fl_downgrade_time;
+
+ const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
+ const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
+ union {
+ struct nfs_lock_info nfs_fl;
+ struct nfs4_lock_info nfs4_fl;
+ struct {
+ struct list_head link; /* link in AFS vnode's pending_locks list */
+ int state; /* state of grant or error if -ve */
+ } afs;
+ } fl_u;
+} __randomize_layout;
+
+struct file_lock_context {
+ spinlock_t flc_lock;
+ struct list_head flc_flock;
+ struct list_head flc_posix;
+ struct list_head flc_lease;
+};
+
+/* The following constant reflects the upper bound of the file/locking space */
+#ifndef OFFSET_MAX
+#define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
+#define OFFSET_MAX INT_LIMIT(loff_t)
+#define OFFT_OFFSET_MAX INT_LIMIT(off_t)
+#endif
+
+extern void send_sigio(struct fown_struct *fown, int fd, int band);
+
+#define locks_inode(f) file_inode(f)
+
+#ifdef CONFIG_FILE_LOCKING
+extern int fcntl_getlk(struct file *, unsigned int, struct flock *);
+extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
+ struct flock *);
+
+#if BITS_PER_LONG == 32
+extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 *);
+extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
+ struct flock64 *);
+#endif
+
+extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
+extern int fcntl_getlease(struct file *filp);
+
+/* fs/locks.c */
+void locks_free_lock_context(struct inode *inode);
+void locks_free_lock(struct file_lock *fl);
+extern void locks_init_lock(struct file_lock *);
+extern struct file_lock * locks_alloc_lock(void);
+extern void locks_copy_lock(struct file_lock *, struct file_lock *);
+extern void locks_copy_conflock(struct file_lock *, struct file_lock *);
+extern void locks_remove_posix(struct file *, fl_owner_t);
+extern void locks_remove_file(struct file *);
+extern void locks_release_private(struct file_lock *);
+extern void posix_test_lock(struct file *, struct file_lock *);
+extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
+extern int posix_unblock_lock(struct file_lock *);
+extern int vfs_test_lock(struct file *, struct file_lock *);
+extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
+extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
+extern int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl);
+extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
+extern void lease_get_mtime(struct inode *, struct timespec64 *time);
+extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
+extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
+extern int lease_modify(struct file_lock *, int, struct list_head *);
+struct files_struct;
+extern void show_fd_locks(struct seq_file *f,
+ struct file *filp, struct files_struct *files);
+#else /* !CONFIG_FILE_LOCKING */
+static inline int fcntl_getlk(struct file *file, unsigned int cmd,
+ struct flock __user *user)
+{
+ return -EINVAL;
+}
+
+static inline int fcntl_setlk(unsigned int fd, struct file *file,
+ unsigned int cmd, struct flock __user *user)
+{
+ return -EACCES;
+}
+
+#if BITS_PER_LONG == 32
+static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
+ struct flock64 __user *user)
+{
+ return -EINVAL;
+}
+
+static inline int fcntl_setlk64(unsigned int fd, struct file *file,
+ unsigned int cmd, struct flock64 __user *user)
+{
+ return -EACCES;
+}
+#endif
+static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+{
+ return -EINVAL;
+}
+
+static inline int fcntl_getlease(struct file *filp)
+{
+ return F_UNLCK;
+}
+
+static inline void
+locks_free_lock_context(struct inode *inode)
+{
+}
+
+static inline void locks_init_lock(struct file_lock *fl)
+{
+ return;
+}
+
+static inline void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
+{
+ return;
+}
+
+static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
+{
+ return;
+}
+
+static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
+{
+ return;
+}
+
+static inline void locks_remove_file(struct file *filp)
+{
+ return;
+}
+
+static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
+{
+ return;
+}
+
+static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
+ struct file_lock *conflock)
+{
+ return -ENOLCK;
+}
+
+static inline int posix_unblock_lock(struct file_lock *waiter)
+{
+ return -ENOENT;
+}
+
+static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
+{
+ return 0;
+}
+
+static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
+ struct file_lock *fl, struct file_lock *conf)
+{
+ return -ENOLCK;
+}
+
+static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
+{
+ return 0;
+}
+
+static inline int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl)
+{
+ return -ENOLCK;
+}
+
+static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
+{
+ return 0;
+}
+
+static inline void lease_get_mtime(struct inode *inode,
+ struct timespec64 *time)
+{
+ return;
+}
+
+static inline int generic_setlease(struct file *filp, long arg,
+ struct file_lock **flp, void **priv)
+{
+ return -EINVAL;
+}
+
+static inline int vfs_setlease(struct file *filp, long arg,
+ struct file_lock **lease, void **priv)
+{
+ return -EINVAL;
+}
+
+static inline int lease_modify(struct file_lock *fl, int arg,
+ struct list_head *dispose)
+{
+ return -EINVAL;
+}
+
+struct files_struct;
+static inline void show_fd_locks(struct seq_file *f,
+ struct file *filp, struct files_struct *files) {}
+#endif /* !CONFIG_FILE_LOCKING */
+
+static inline struct inode *file_inode(const struct file *f)
+{
+ return f->f_inode;
+}
+
+static inline struct dentry *file_dentry(const struct file *file)
+{
+ return d_real(file->f_path.dentry, file_inode(file));
+}
+
+static inline int locks_lock_file_wait(struct file *filp, struct file_lock *fl)
+{
+ return locks_lock_inode_wait(locks_inode(filp), fl);
+}
+
+struct fasync_struct {
+ rwlock_t fa_lock;
+ int magic;
+ int fa_fd;
+ struct fasync_struct *fa_next; /* singly linked list */
+ struct file *fa_file;
+ struct rcu_head fa_rcu;
+};
+
+#define FASYNC_MAGIC 0x4601
+
+/* SMP safe fasync helpers: */
+extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
+extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
+extern int fasync_remove_entry(struct file *, struct fasync_struct **);
+extern struct fasync_struct *fasync_alloc(void);
+extern void fasync_free(struct fasync_struct *);
+
+/* can be called from interrupts */
+extern void kill_fasync(struct fasync_struct **, int, int);
+
+extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
+extern int f_setown(struct file *filp, unsigned long arg, int force);
+extern void f_delown(struct file *filp);
+extern pid_t f_getown(struct file *filp);
+extern int send_sigurg(struct fown_struct *fown);
+
+/*
+ * sb->s_flags. Note that these mirror the equivalent MS_* flags where
+ * represented in both.
+ */
+#define SB_RDONLY 1 /* Mount read-only */
+#define SB_NOSUID 2 /* Ignore suid and sgid bits */
+#define SB_NODEV 4 /* Disallow access to device special files */
+#define SB_NOEXEC 8 /* Disallow program execution */
+#define SB_SYNCHRONOUS 16 /* Writes are synced at once */
+#define SB_MANDLOCK 64 /* Allow mandatory locks on an FS */
+#define SB_DIRSYNC 128 /* Directory modifications are synchronous */
+#define SB_NOATIME 1024 /* Do not update access times. */
+#define SB_NODIRATIME 2048 /* Do not update directory access times */
+#define SB_SILENT 32768
+#define SB_POSIXACL (1<<16) /* VFS does not apply the umask */
+#define SB_KERNMOUNT (1<<22) /* this is a kern_mount call */
+#define SB_I_VERSION (1<<23) /* Update inode I_version field */
+#define SB_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */
+
+/* These sb flags are internal to the kernel */
+#define SB_SUBMOUNT (1<<26)
+#define SB_NOSEC (1<<28)
+#define SB_BORN (1<<29)
+#define SB_ACTIVE (1<<30)
+#define SB_NOUSER (1<<31)
+
+/*
+ * Umount options
+ */
+
+#define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
+#define MNT_DETACH 0x00000002 /* Just detach from the tree */
+#define MNT_EXPIRE 0x00000004 /* Mark for expiry */
+#define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
+#define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
+
+/* sb->s_iflags */
+#define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
+#define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
+#define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
+#define SB_I_MULTIROOT 0x00000008 /* Multiple roots to the dentry tree */
+
+/* sb->s_iflags to limit user namespace mounts */
+#define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
+#define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
+#define SB_I_UNTRUSTED_MOUNTER 0x00000040
+
+/* Possible states of 'frozen' field */
+enum {
+ SB_UNFROZEN = 0, /* FS is unfrozen */
+ SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
+ SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
+ SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
+ * internal threads if needed) */
+ SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
+};
+
+#define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
+
+struct sb_writers {
+ int frozen; /* Is sb frozen? */
+ wait_queue_head_t wait_unfrozen; /* for get_super_thawed() */
+ struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
+};
+
+struct super_block {
+ struct list_head s_list; /* Keep this first */
+ dev_t s_dev; /* search index; _not_ kdev_t */
+ unsigned char s_blocksize_bits;
+ unsigned long s_blocksize;
+ loff_t s_maxbytes; /* Max file size */
+ struct file_system_type *s_type;
+ const struct super_operations *s_op;
+ const struct dquot_operations *dq_op;
+ const struct quotactl_ops *s_qcop;
+ const struct export_operations *s_export_op;
+ unsigned long s_flags;
+ unsigned long s_iflags; /* internal SB_I_* flags */
+ unsigned long s_magic;
+ struct dentry *s_root;
+ struct rw_semaphore s_umount;
+ int s_count;
+ atomic_t s_active;
+#ifdef CONFIG_SECURITY
+ void *s_security;
+#endif
+ const struct xattr_handler **s_xattr;
+#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ const struct fscrypt_operations *s_cop;
+#endif
+ struct hlist_bl_head s_roots; /* alternate root dentries for NFS */
+ struct list_head s_mounts; /* list of mounts; _not_ for fs use */
+ struct block_device *s_bdev;
+ struct backing_dev_info *s_bdi;
+ struct mtd_info *s_mtd;
+ struct hlist_node s_instances;
+ unsigned int s_quota_types; /* Bitmask of supported quota types */
+ struct quota_info s_dquot; /* Diskquota specific options */
+
+ struct sb_writers s_writers;
+
+ char s_id[32]; /* Informational name */
+ uuid_t s_uuid; /* UUID */
+
+ void *s_fs_info; /* Filesystem private info */
+ unsigned int s_max_links;
+ fmode_t s_mode;
+
+ /* Granularity of c/m/atime in ns.
+ Cannot be worse than a second */
+ u32 s_time_gran;
+
+ /*
+ * The next field is for VFS *only*. No filesystems have any business
+ * even looking at it. You had been warned.
+ */
+ struct mutex s_vfs_rename_mutex; /* Kludge */
+
+ /*
+ * Filesystem subtype. If non-empty the filesystem type field
+ * in /proc/mounts will be "type.subtype"
+ */
+ char *s_subtype;
+
+ const struct dentry_operations *s_d_op; /* default d_op for dentries */
+
+ /*
+ * Saved pool identifier for cleancache (-1 means none)
+ */
+ int cleancache_poolid;
+
+ struct shrinker s_shrink; /* per-sb shrinker handle */
+
+ /* Number of inodes with nlink == 0 but still referenced */
+ atomic_long_t s_remove_count;
+
+ /* Pending fsnotify inode refs */
+ atomic_long_t s_fsnotify_inode_refs;
+
+ /* Being remounted read-only */
+ int s_readonly_remount;
+
+ /* AIO completions deferred from interrupt context */
+ struct workqueue_struct *s_dio_done_wq;
+ struct hlist_head s_pins;
+
+ /*
+ * Owning user namespace and default context in which to
+ * interpret filesystem uids, gids, quotas, device nodes,
+ * xattrs and security labels.
+ */
+ struct user_namespace *s_user_ns;
+
+ /*
+ * Keep the lru lists last in the structure so they always sit on their
+ * own individual cachelines.
+ */
+ struct list_lru s_dentry_lru ____cacheline_aligned_in_smp;
+ struct list_lru s_inode_lru ____cacheline_aligned_in_smp;
+ struct rcu_head rcu;
+ struct work_struct destroy_work;
+
+ struct mutex s_sync_lock; /* sync serialisation lock */
+
+ /*
+ * Indicates how deep in a filesystem stack this SB is
+ */
+ int s_stack_depth;
+
+ /* s_inode_list_lock protects s_inodes */
+ spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
+ struct list_head s_inodes; /* all inodes */
+
+ spinlock_t s_inode_wblist_lock;
+ struct list_head s_inodes_wb; /* writeback inodes */
+} __randomize_layout;
+
+/* Helper functions so that in most cases filesystems will
+ * not need to deal directly with kuid_t and kgid_t and can
+ * instead deal with the raw numeric values that are stored
+ * in the filesystem.
+ */
+static inline uid_t i_uid_read(const struct inode *inode)
+{
+ return from_kuid(inode->i_sb->s_user_ns, inode->i_uid);
+}
+
+static inline gid_t i_gid_read(const struct inode *inode)
+{
+ return from_kgid(inode->i_sb->s_user_ns, inode->i_gid);
+}
+
+static inline void i_uid_write(struct inode *inode, uid_t uid)
+{
+ inode->i_uid = make_kuid(inode->i_sb->s_user_ns, uid);
+}
+
+static inline void i_gid_write(struct inode *inode, gid_t gid)
+{
+ inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
+}
+
+extern struct timespec64 timespec64_trunc(struct timespec64 t, unsigned gran);
+extern struct timespec64 current_time(struct inode *inode);
+
+/*
+ * Snapshotting support.
+ */
+
+void __sb_end_write(struct super_block *sb, int level);
+int __sb_start_write(struct super_block *sb, int level, bool wait);
+
+#define __sb_writers_acquired(sb, lev) \
+ percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
+#define __sb_writers_release(sb, lev) \
+ percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
+
+/**
+ * sb_end_write - drop write access to a superblock
+ * @sb: the super we wrote to
+ *
+ * Decrement number of writers to the filesystem. Wake up possible waiters
+ * wanting to freeze the filesystem.
+ */
+static inline void sb_end_write(struct super_block *sb)
+{
+ __sb_end_write(sb, SB_FREEZE_WRITE);
+}
+
+/**
+ * sb_end_pagefault - drop write access to a superblock from a page fault
+ * @sb: the super we wrote to
+ *
+ * Decrement number of processes handling write page fault to the filesystem.
+ * Wake up possible waiters wanting to freeze the filesystem.
+ */
+static inline void sb_end_pagefault(struct super_block *sb)
+{
+ __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
+}
+
+/**
+ * sb_end_intwrite - drop write access to a superblock for internal fs purposes
+ * @sb: the super we wrote to
+ *
+ * Decrement fs-internal number of writers to the filesystem. Wake up possible
+ * waiters wanting to freeze the filesystem.
+ */
+static inline void sb_end_intwrite(struct super_block *sb)
+{
+ __sb_end_write(sb, SB_FREEZE_FS);
+}
+
+/**
+ * sb_start_write - get write access to a superblock
+ * @sb: the super we write to
+ *
+ * When a process wants to write data or metadata to a file system (i.e. dirty
+ * a page or an inode), it should embed the operation in a sb_start_write() -
+ * sb_end_write() pair to get exclusion against file system freezing. This
+ * function increments number of writers preventing freezing. If the file
+ * system is already frozen, the function waits until the file system is
+ * thawed.
+ *
+ * Since freeze protection behaves as a lock, users have to preserve
+ * ordering of freeze protection and other filesystem locks. Generally,
+ * freeze protection should be the outermost lock. In particular, we have:
+ *
+ * sb_start_write
+ * -> i_mutex (write path, truncate, directory ops, ...)
+ * -> s_umount (freeze_super, thaw_super)
+ */
+static inline void sb_start_write(struct super_block *sb)
+{
+ __sb_start_write(sb, SB_FREEZE_WRITE, true);
+}
+
+static inline int sb_start_write_trylock(struct super_block *sb)
+{
+ return __sb_start_write(sb, SB_FREEZE_WRITE, false);
+}
+
+/**
+ * sb_start_pagefault - get write access to a superblock from a page fault
+ * @sb: the super we write to
+ *
+ * When a process starts handling write page fault, it should embed the
+ * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
+ * exclusion against file system freezing. This is needed since the page fault
+ * is going to dirty a page. This function increments number of running page
+ * faults preventing freezing. If the file system is already frozen, the
+ * function waits until the file system is thawed.
+ *
+ * Since page fault freeze protection behaves as a lock, users have to preserve
+ * ordering of freeze protection and other filesystem locks. It is advised to
+ * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
+ * handling code implies lock dependency:
+ *
+ * mmap_sem
+ * -> sb_start_pagefault
+ */
+static inline void sb_start_pagefault(struct super_block *sb)
+{
+ __sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
+}
+
+/*
+ * sb_start_intwrite - get write access to a superblock for internal fs purposes
+ * @sb: the super we write to
+ *
+ * This is the third level of protection against filesystem freezing. It is
+ * free for use by a filesystem. The only requirement is that it must rank
+ * below sb_start_pagefault.
+ *
+ * For example filesystem can call sb_start_intwrite() when starting a
+ * transaction which somewhat eases handling of freezing for internal sources
+ * of filesystem changes (internal fs threads, discarding preallocation on file
+ * close, etc.).
+ */
+static inline void sb_start_intwrite(struct super_block *sb)
+{
+ __sb_start_write(sb, SB_FREEZE_FS, true);
+}
+
+static inline int sb_start_intwrite_trylock(struct super_block *sb)
+{
+ return __sb_start_write(sb, SB_FREEZE_FS, false);
+}
+
+
+extern bool inode_owner_or_capable(const struct inode *inode);
+
+/*
+ * VFS helper functions..
+ */
+extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
+extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
+extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
+extern int vfs_symlink(struct inode *, struct dentry *, const char *);
+extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
+extern int vfs_rmdir(struct inode *, struct dentry *);
+extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
+extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
+extern int vfs_whiteout(struct inode *, struct dentry *);
+
+extern struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode,
+ int open_flag);
+
+int vfs_mkobj(struct dentry *, umode_t,
+ int (*f)(struct dentry *, umode_t, void *),
+ void *);
+
+extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+
+/*
+ * VFS file helper functions.
+ */
+extern void inode_init_owner(struct inode *inode, const struct inode *dir,
+ umode_t mode);
+extern bool may_open_dev(const struct path *path);
+/*
+ * VFS FS_IOC_FIEMAP helper definitions.
+ */
+struct fiemap_extent_info {
+ unsigned int fi_flags; /* Flags as passed from user */
+ unsigned int fi_extents_mapped; /* Number of mapped extents */
+ unsigned int fi_extents_max; /* Size of fiemap_extent array */
+ struct fiemap_extent __user *fi_extents_start; /* Start of
+ fiemap_extent array */
+};
+int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
+ u64 phys, u64 len, u32 flags);
+int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
+
+/*
+ * File types
+ *
+ * NOTE! These match bits 12..15 of stat.st_mode
+ * (ie "(i_mode >> 12) & 15").
+ */
+#define DT_UNKNOWN 0
+#define DT_FIFO 1
+#define DT_CHR 2
+#define DT_DIR 4
+#define DT_BLK 6
+#define DT_REG 8
+#define DT_LNK 10
+#define DT_SOCK 12
+#define DT_WHT 14
+
+/*
+ * This is the "filldir" function type, used by readdir() to let
+ * the kernel specify what kind of dirent layout it wants to have.
+ * This allows the kernel to read directories into kernel space or
+ * to have different dirent layouts depending on the binary type.
+ */
+struct dir_context;
+typedef int (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
+ unsigned);
+
+struct dir_context {
+ filldir_t actor;
+ loff_t pos;
+};
+
+struct block_device_operations;
+
+/* These macros are for out of kernel modules to test that
+ * the kernel supports the unlocked_ioctl and compat_ioctl
+ * fields in struct file_operations. */
+#define HAVE_COMPAT_IOCTL 1
+#define HAVE_UNLOCKED_IOCTL 1
+
+/*
+ * These flags let !MMU mmap() govern direct device mapping vs immediate
+ * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
+ *
+ * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
+ * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
+ * NOMMU_MAP_READ: Can be mapped for reading
+ * NOMMU_MAP_WRITE: Can be mapped for writing
+ * NOMMU_MAP_EXEC: Can be mapped for execution
+ */
+#define NOMMU_MAP_COPY 0x00000001
+#define NOMMU_MAP_DIRECT 0x00000008
+#define NOMMU_MAP_READ VM_MAYREAD
+#define NOMMU_MAP_WRITE VM_MAYWRITE
+#define NOMMU_MAP_EXEC VM_MAYEXEC
+
+#define NOMMU_VMFLAGS \
+ (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
+
+
+struct iov_iter;
+
+struct file_operations {
+ struct module *owner;
+ loff_t (*llseek) (struct file *, loff_t, int);
+ ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
+ ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
+ ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
+ ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
+ int (*iterate) (struct file *, struct dir_context *);
+ int (*iterate_shared) (struct file *, struct dir_context *);
+ __poll_t (*poll) (struct file *, struct poll_table_struct *);
+ long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
+ long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
+ int (*mmap) (struct file *, struct vm_area_struct *);
+ unsigned long mmap_supported_flags;
+ int (*open) (struct inode *, struct file *);
+ int (*flush) (struct file *, fl_owner_t id);
+ int (*release) (struct inode *, struct file *);
+ int (*fsync) (struct file *, loff_t, loff_t, int datasync);
+ int (*fasync) (int, struct file *, int);
+ int (*lock) (struct file *, int, struct file_lock *);
+ ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
+ unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
+ int (*check_flags)(int);
+ int (*flock) (struct file *, int, struct file_lock *);
+ ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
+ ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
+ int (*setlease)(struct file *, long, struct file_lock **, void **);
+ long (*fallocate)(struct file *file, int mode, loff_t offset,
+ loff_t len);
+ void (*show_fdinfo)(struct seq_file *m, struct file *f);
+#ifndef CONFIG_MMU
+ unsigned (*mmap_capabilities)(struct file *);
+#endif
+ ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
+ loff_t, size_t, unsigned int);
+ int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t,
+ u64);
+ int (*dedupe_file_range)(struct file *, loff_t, struct file *, loff_t,
+ u64);
+ int (*fadvise)(struct file *, loff_t, loff_t, int);
+} __randomize_layout;
+
+struct inode_operations {
+ struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
+ const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
+ int (*permission) (struct inode *, int);
+ struct posix_acl * (*get_acl)(struct inode *, int);
+
+ int (*readlink) (struct dentry *, char __user *,int);
+
+ int (*create) (struct inode *,struct dentry *, umode_t, bool);
+ int (*link) (struct dentry *,struct inode *,struct dentry *);
+ int (*unlink) (struct inode *,struct dentry *);
+ int (*symlink) (struct inode *,struct dentry *,const char *);
+ int (*mkdir) (struct inode *,struct dentry *,umode_t);
+ int (*rmdir) (struct inode *,struct dentry *);
+ int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
+ int (*rename) (struct inode *, struct dentry *,
+ struct inode *, struct dentry *, unsigned int);
+ int (*setattr) (struct dentry *, struct iattr *);
+ int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
+ ssize_t (*listxattr) (struct dentry *, char *, size_t);
+ int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
+ u64 len);
+ int (*update_time)(struct inode *, struct timespec64 *, int);
+ int (*atomic_open)(struct inode *, struct dentry *,
+ struct file *, unsigned open_flag,
+ umode_t create_mode);
+ int (*tmpfile) (struct inode *, struct dentry *, umode_t);
+ int (*set_acl)(struct inode *, struct posix_acl *, int);
+} ____cacheline_aligned;
+
+static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
+ struct iov_iter *iter)
+{
+ return file->f_op->read_iter(kio, iter);
+}
+
+static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
+ struct iov_iter *iter)
+{
+ return file->f_op->write_iter(kio, iter);
+}
+
+static inline int call_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ return file->f_op->mmap(file, vma);
+}
+
+ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
+ unsigned long nr_segs, unsigned long fast_segs,
+ struct iovec *fast_pointer,
+ struct iovec **ret_pointer);
+
+extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
+extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
+extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
+extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
+ unsigned long, loff_t *, rwf_t);
+extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
+ loff_t, size_t, unsigned int);
+extern int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
+ struct inode *inode_out, loff_t pos_out,
+ u64 *len, bool is_dedupe);
+extern int do_clone_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out, u64 len);
+extern int vfs_clone_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out, u64 len);
+extern int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
+ struct inode *dest, loff_t destoff,
+ loff_t len, bool *is_same);
+extern int vfs_dedupe_file_range(struct file *file,
+ struct file_dedupe_range *same);
+extern int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
+ struct file *dst_file, loff_t dst_pos,
+ u64 len);
+
+
+struct super_operations {
+ struct inode *(*alloc_inode)(struct super_block *sb);
+ void (*destroy_inode)(struct inode *);
+
+ void (*dirty_inode) (struct inode *, int flags);
+ int (*write_inode) (struct inode *, struct writeback_control *wbc);
+ int (*drop_inode) (struct inode *);
+ void (*evict_inode) (struct inode *);
+ void (*put_super) (struct super_block *);
+ int (*sync_fs)(struct super_block *sb, int wait);
+ int (*freeze_super) (struct super_block *);
+ int (*freeze_fs) (struct super_block *);
+ int (*thaw_super) (struct super_block *);
+ int (*unfreeze_fs) (struct super_block *);
+ int (*statfs) (struct dentry *, struct kstatfs *);
+ int (*remount_fs) (struct super_block *, int *, char *);
+ void (*umount_begin) (struct super_block *);
+
+ int (*show_options)(struct seq_file *, struct dentry *);
+ int (*show_devname)(struct seq_file *, struct dentry *);
+ int (*show_path)(struct seq_file *, struct dentry *);
+ int (*show_stats)(struct seq_file *, struct dentry *);
+#ifdef CONFIG_QUOTA
+ ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
+ ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
+ struct dquot **(*get_dquots)(struct inode *);
+#endif
+ int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
+ long (*nr_cached_objects)(struct super_block *,
+ struct shrink_control *);
+ long (*free_cached_objects)(struct super_block *,
+ struct shrink_control *);
+};
+
+/*
+ * Inode flags - they have no relation to superblock flags now
+ */
+#define S_SYNC 1 /* Writes are synced at once */
+#define S_NOATIME 2 /* Do not update access times */
+#define S_APPEND 4 /* Append-only file */
+#define S_IMMUTABLE 8 /* Immutable file */
+#define S_DEAD 16 /* removed, but still open directory */
+#define S_NOQUOTA 32 /* Inode is not counted to quota */
+#define S_DIRSYNC 64 /* Directory modifications are synchronous */
+#define S_NOCMTIME 128 /* Do not update file c/mtime */
+#define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
+#define S_PRIVATE 512 /* Inode is fs-internal */
+#define S_IMA 1024 /* Inode has an associated IMA struct */
+#define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
+#define S_NOSEC 4096 /* no suid or xattr security attributes */
+#ifdef CONFIG_FS_DAX
+#define S_DAX 8192 /* Direct Access, avoiding the page cache */
+#else
+#define S_DAX 0 /* Make all the DAX code disappear */
+#endif
+#define S_ENCRYPTED 16384 /* Encrypted file (using fs/crypto/) */
+
+/*
+ * Note that nosuid etc flags are inode-specific: setting some file-system
+ * flags just means all the inodes inherit those flags by default. It might be
+ * possible to override it selectively if you really wanted to with some
+ * ioctl() that is not currently implemented.
+ *
+ * Exception: SB_RDONLY is always applied to the entire file system.
+ *
+ * Unfortunately, it is possible to change a filesystems flags with it mounted
+ * with files in use. This means that all of the inodes will not have their
+ * i_flags updated. Hence, i_flags no longer inherit the superblock mount
+ * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
+ */
+#define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
+
+static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags & SB_RDONLY; }
+#define IS_RDONLY(inode) sb_rdonly((inode)->i_sb)
+#define IS_SYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS) || \
+ ((inode)->i_flags & S_SYNC))
+#define IS_DIRSYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
+ ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
+#define IS_MANDLOCK(inode) __IS_FLG(inode, SB_MANDLOCK)
+#define IS_NOATIME(inode) __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
+#define IS_I_VERSION(inode) __IS_FLG(inode, SB_I_VERSION)
+
+#define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
+#define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
+#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
+#define IS_POSIXACL(inode) __IS_FLG(inode, SB_POSIXACL)
+
+#define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
+#define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
+#define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
+#define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
+#define IS_IMA(inode) ((inode)->i_flags & S_IMA)
+#define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
+#define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
+#define IS_DAX(inode) ((inode)->i_flags & S_DAX)
+#define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED)
+
+#define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
+ (inode)->i_rdev == WHITEOUT_DEV)
+
+static inline bool HAS_UNMAPPED_ID(struct inode *inode)
+{
+ return !uid_valid(inode->i_uid) || !gid_valid(inode->i_gid);
+}
+
+static inline enum rw_hint file_write_hint(struct file *file)
+{
+ if (file->f_write_hint != WRITE_LIFE_NOT_SET)
+ return file->f_write_hint;
+
+ return file_inode(file)->i_write_hint;
+}
+
+static inline int iocb_flags(struct file *file);
+
+static inline u16 ki_hint_validate(enum rw_hint hint)
+{
+ typeof(((struct kiocb *)0)->ki_hint) max_hint = -1;
+
+ if (hint <= max_hint)
+ return hint;
+ return 0;
+}
+
+static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
+{
+ *kiocb = (struct kiocb) {
+ .ki_filp = filp,
+ .ki_flags = iocb_flags(filp),
+ .ki_hint = ki_hint_validate(file_write_hint(filp)),
+ .ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0),
+ };
+}
+
+/*
+ * Inode state bits. Protected by inode->i_lock
+ *
+ * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
+ * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
+ *
+ * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
+ * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
+ * various stages of removing an inode.
+ *
+ * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
+ *
+ * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
+ * fdatasync(). i_atime is the usual cause.
+ * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
+ * these changes separately from I_DIRTY_SYNC so that we
+ * don't have to write inode on fdatasync() when only
+ * mtime has changed in it.
+ * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
+ * I_NEW Serves as both a mutex and completion notification.
+ * New inodes set I_NEW. If two processes both create
+ * the same inode, one of them will release its inode and
+ * wait for I_NEW to be released before returning.
+ * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
+ * also cause waiting on I_NEW, without I_NEW actually
+ * being set. find_inode() uses this to prevent returning
+ * nearly-dead inodes.
+ * I_WILL_FREE Must be set when calling write_inode_now() if i_count
+ * is zero. I_FREEING must be set when I_WILL_FREE is
+ * cleared.
+ * I_FREEING Set when inode is about to be freed but still has dirty
+ * pages or buffers attached or the inode itself is still
+ * dirty.
+ * I_CLEAR Added by clear_inode(). In this state the inode is
+ * clean and can be destroyed. Inode keeps I_FREEING.
+ *
+ * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
+ * prohibited for many purposes. iget() must wait for
+ * the inode to be completely released, then create it
+ * anew. Other functions will just ignore such inodes,
+ * if appropriate. I_NEW is used for waiting.
+ *
+ * I_SYNC Writeback of inode is running. The bit is set during
+ * data writeback, and cleared with a wakeup on the bit
+ * address once it is done. The bit is also used to pin
+ * the inode in memory for flusher thread.
+ *
+ * I_REFERENCED Marks the inode as recently references on the LRU list.
+ *
+ * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
+ *
+ * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
+ * synchronize competing switching instances and to tell
+ * wb stat updates to grab the i_pages lock. See
+ * inode_switch_wb_work_fn() for details.
+ *
+ * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
+ * and work dirs among overlayfs mounts.
+ *
+ * I_CREATING New object's inode in the middle of setting up.
+ *
+ * Q: What is the difference between I_WILL_FREE and I_FREEING?
+ */
+#define I_DIRTY_SYNC (1 << 0)
+#define I_DIRTY_DATASYNC (1 << 1)
+#define I_DIRTY_PAGES (1 << 2)
+#define __I_NEW 3
+#define I_NEW (1 << __I_NEW)
+#define I_WILL_FREE (1 << 4)
+#define I_FREEING (1 << 5)
+#define I_CLEAR (1 << 6)
+#define __I_SYNC 7
+#define I_SYNC (1 << __I_SYNC)
+#define I_REFERENCED (1 << 8)
+#define __I_DIO_WAKEUP 9
+#define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
+#define I_LINKABLE (1 << 10)
+#define I_DIRTY_TIME (1 << 11)
+#define __I_DIRTY_TIME_EXPIRED 12
+#define I_DIRTY_TIME_EXPIRED (1 << __I_DIRTY_TIME_EXPIRED)
+#define I_WB_SWITCH (1 << 13)
+#define I_OVL_INUSE (1 << 14)
+#define I_CREATING (1 << 15)
+
+#define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
+#define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
+#define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
+
+extern void __mark_inode_dirty(struct inode *, int);
+static inline void mark_inode_dirty(struct inode *inode)
+{
+ __mark_inode_dirty(inode, I_DIRTY);
+}
+
+static inline void mark_inode_dirty_sync(struct inode *inode)
+{
+ __mark_inode_dirty(inode, I_DIRTY_SYNC);
+}
+
+extern void inc_nlink(struct inode *inode);
+extern void drop_nlink(struct inode *inode);
+extern void clear_nlink(struct inode *inode);
+extern void set_nlink(struct inode *inode, unsigned int nlink);
+
+static inline void inode_inc_link_count(struct inode *inode)
+{
+ inc_nlink(inode);
+ mark_inode_dirty(inode);
+}
+
+static inline void inode_dec_link_count(struct inode *inode)
+{
+ drop_nlink(inode);
+ mark_inode_dirty(inode);
+}
+
+enum file_time_flags {
+ S_ATIME = 1,
+ S_MTIME = 2,
+ S_CTIME = 4,
+ S_VERSION = 8,
+};
+
+extern bool atime_needs_update(const struct path *, struct inode *);
+extern void touch_atime(const struct path *);
+static inline void file_accessed(struct file *file)
+{
+ if (!(file->f_flags & O_NOATIME))
+ touch_atime(&file->f_path);
+}
+
+int sync_inode(struct inode *inode, struct writeback_control *wbc);
+int sync_inode_metadata(struct inode *inode, int wait);
+
+struct file_system_type {
+ const char *name;
+ int fs_flags;
+#define FS_REQUIRES_DEV 1
+#define FS_BINARY_MOUNTDATA 2
+#define FS_HAS_SUBTYPE 4
+#define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
+#define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
+ struct dentry *(*mount) (struct file_system_type *, int,
+ const char *, void *);
+ void (*kill_sb) (struct super_block *);
+ struct module *owner;
+ struct file_system_type * next;
+ struct hlist_head fs_supers;
+
+ struct lock_class_key s_lock_key;
+ struct lock_class_key s_umount_key;
+ struct lock_class_key s_vfs_rename_key;
+ struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
+
+ struct lock_class_key i_lock_key;
+ struct lock_class_key i_mutex_key;
+ struct lock_class_key i_mutex_dir_key;
+};
+
+#define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
+
+extern struct dentry *mount_ns(struct file_system_type *fs_type,
+ int flags, void *data, void *ns, struct user_namespace *user_ns,
+ int (*fill_super)(struct super_block *, void *, int));
+#ifdef CONFIG_BLOCK
+extern struct dentry *mount_bdev(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data,
+ int (*fill_super)(struct super_block *, void *, int));
+#else
+static inline struct dentry *mount_bdev(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data,
+ int (*fill_super)(struct super_block *, void *, int))
+{
+ return ERR_PTR(-ENODEV);
+}
+#endif
+extern struct dentry *mount_single(struct file_system_type *fs_type,
+ int flags, void *data,
+ int (*fill_super)(struct super_block *, void *, int));
+extern struct dentry *mount_nodev(struct file_system_type *fs_type,
+ int flags, void *data,
+ int (*fill_super)(struct super_block *, void *, int));
+extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
+void generic_shutdown_super(struct super_block *sb);
+#ifdef CONFIG_BLOCK
+void kill_block_super(struct super_block *sb);
+#else
+static inline void kill_block_super(struct super_block *sb)
+{
+ BUG();
+}
+#endif
+void kill_anon_super(struct super_block *sb);
+void kill_litter_super(struct super_block *sb);
+void deactivate_super(struct super_block *sb);
+void deactivate_locked_super(struct super_block *sb);
+int set_anon_super(struct super_block *s, void *data);
+int get_anon_bdev(dev_t *);
+void free_anon_bdev(dev_t);
+struct super_block *sget_userns(struct file_system_type *type,
+ int (*test)(struct super_block *,void *),
+ int (*set)(struct super_block *,void *),
+ int flags, struct user_namespace *user_ns,
+ void *data);
+struct super_block *sget(struct file_system_type *type,
+ int (*test)(struct super_block *,void *),
+ int (*set)(struct super_block *,void *),
+ int flags, void *data);
+extern struct dentry *mount_pseudo_xattr(struct file_system_type *, char *,
+ const struct super_operations *ops,
+ const struct xattr_handler **xattr,
+ const struct dentry_operations *dops,
+ unsigned long);
+
+static inline struct dentry *
+mount_pseudo(struct file_system_type *fs_type, char *name,
+ const struct super_operations *ops,
+ const struct dentry_operations *dops, unsigned long magic)
+{
+ return mount_pseudo_xattr(fs_type, name, ops, NULL, dops, magic);
+}
+
+/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
+#define fops_get(fops) \
+ (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
+#define fops_put(fops) \
+ do { if (fops) module_put((fops)->owner); } while(0)
+/*
+ * This one is to be used *ONLY* from ->open() instances.
+ * fops must be non-NULL, pinned down *and* module dependencies
+ * should be sufficient to pin the caller down as well.
+ */
+#define replace_fops(f, fops) \
+ do { \
+ struct file *__file = (f); \
+ fops_put(__file->f_op); \
+ BUG_ON(!(__file->f_op = (fops))); \
+ } while(0)
+
+extern int register_filesystem(struct file_system_type *);
+extern int unregister_filesystem(struct file_system_type *);
+extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
+#define kern_mount(type) kern_mount_data(type, NULL)
+extern void kern_unmount(struct vfsmount *mnt);
+extern int may_umount_tree(struct vfsmount *);
+extern int may_umount(struct vfsmount *);
+extern long do_mount(const char *, const char __user *,
+ const char *, unsigned long, void *);
+extern struct vfsmount *collect_mounts(const struct path *);
+extern void drop_collected_mounts(struct vfsmount *);
+extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
+ struct vfsmount *);
+extern int vfs_statfs(const struct path *, struct kstatfs *);
+extern int user_statfs(const char __user *, struct kstatfs *);
+extern int fd_statfs(int, struct kstatfs *);
+extern int freeze_super(struct super_block *super);
+extern int thaw_super(struct super_block *super);
+extern bool our_mnt(struct vfsmount *mnt);
+extern __printf(2, 3)
+int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
+extern int super_setup_bdi(struct super_block *sb);
+
+extern int current_umask(void);
+
+extern void ihold(struct inode * inode);
+extern void iput(struct inode *);
+extern int generic_update_time(struct inode *, struct timespec64 *, int);
+
+/* /sys/fs */
+extern struct kobject *fs_kobj;
+
+#define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
+
+#ifdef CONFIG_MANDATORY_FILE_LOCKING
+extern int locks_mandatory_locked(struct file *);
+extern int locks_mandatory_area(struct inode *, struct file *, loff_t, loff_t, unsigned char);
+
+/*
+ * Candidates for mandatory locking have the setgid bit set
+ * but no group execute bit - an otherwise meaningless combination.
+ */
+
+static inline int __mandatory_lock(struct inode *ino)
+{
+ return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
+}
+
+/*
+ * ... and these candidates should be on SB_MANDLOCK mounted fs,
+ * otherwise these will be advisory locks
+ */
+
+static inline int mandatory_lock(struct inode *ino)
+{
+ return IS_MANDLOCK(ino) && __mandatory_lock(ino);
+}
+
+static inline int locks_verify_locked(struct file *file)
+{
+ if (mandatory_lock(locks_inode(file)))
+ return locks_mandatory_locked(file);
+ return 0;
+}
+
+static inline int locks_verify_truncate(struct inode *inode,
+ struct file *f,
+ loff_t size)
+{
+ if (!inode->i_flctx || !mandatory_lock(inode))
+ return 0;
+
+ if (size < inode->i_size) {
+ return locks_mandatory_area(inode, f, size, inode->i_size - 1,
+ F_WRLCK);
+ } else {
+ return locks_mandatory_area(inode, f, inode->i_size, size - 1,
+ F_WRLCK);
+ }
+}
+
+#else /* !CONFIG_MANDATORY_FILE_LOCKING */
+
+static inline int locks_mandatory_locked(struct file *file)
+{
+ return 0;
+}
+
+static inline int locks_mandatory_area(struct inode *inode, struct file *filp,
+ loff_t start, loff_t end, unsigned char type)
+{
+ return 0;
+}
+
+static inline int __mandatory_lock(struct inode *inode)
+{
+ return 0;
+}
+
+static inline int mandatory_lock(struct inode *inode)
+{
+ return 0;
+}
+
+static inline int locks_verify_locked(struct file *file)
+{
+ return 0;
+}
+
+static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
+ size_t size)
+{
+ return 0;
+}
+
+#endif /* CONFIG_MANDATORY_FILE_LOCKING */
+
+
+#ifdef CONFIG_FILE_LOCKING
+static inline int break_lease(struct inode *inode, unsigned int mode)
+{
+ /*
+ * Since this check is lockless, we must ensure that any refcounts
+ * taken are done before checking i_flctx->flc_lease. Otherwise, we
+ * could end up racing with tasks trying to set a new lease on this
+ * file.
+ */
+ smp_mb();
+ if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
+ return __break_lease(inode, mode, FL_LEASE);
+ return 0;
+}
+
+static inline int break_deleg(struct inode *inode, unsigned int mode)
+{
+ /*
+ * Since this check is lockless, we must ensure that any refcounts
+ * taken are done before checking i_flctx->flc_lease. Otherwise, we
+ * could end up racing with tasks trying to set a new lease on this
+ * file.
+ */
+ smp_mb();
+ if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
+ return __break_lease(inode, mode, FL_DELEG);
+ return 0;
+}
+
+static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
+{
+ int ret;
+
+ ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
+ if (ret == -EWOULDBLOCK && delegated_inode) {
+ *delegated_inode = inode;
+ ihold(inode);
+ }
+ return ret;
+}
+
+static inline int break_deleg_wait(struct inode **delegated_inode)
+{
+ int ret;
+
+ ret = break_deleg(*delegated_inode, O_WRONLY);
+ iput(*delegated_inode);
+ *delegated_inode = NULL;
+ return ret;
+}
+
+static inline int break_layout(struct inode *inode, bool wait)
+{
+ smp_mb();
+ if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
+ return __break_lease(inode,
+ wait ? O_WRONLY : O_WRONLY | O_NONBLOCK,
+ FL_LAYOUT);
+ return 0;
+}
+
+#else /* !CONFIG_FILE_LOCKING */
+static inline int break_lease(struct inode *inode, unsigned int mode)
+{
+ return 0;
+}
+
+static inline int break_deleg(struct inode *inode, unsigned int mode)
+{
+ return 0;
+}
+
+static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
+{
+ return 0;
+}
+
+static inline int break_deleg_wait(struct inode **delegated_inode)
+{
+ BUG();
+ return 0;
+}
+
+static inline int break_layout(struct inode *inode, bool wait)
+{
+ return 0;
+}
+
+#endif /* CONFIG_FILE_LOCKING */
+
+/* fs/open.c */
+struct audit_names;
+struct filename {
+ const char *name; /* pointer to actual string */
+ const __user char *uptr; /* original userland pointer */
+ int refcnt;
+ struct audit_names *aname;
+ const char iname[];
+};
+
+extern long vfs_truncate(const struct path *, loff_t);
+extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
+ struct file *filp);
+extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
+ loff_t len);
+extern long do_sys_open(int dfd, const char __user *filename, int flags,
+ umode_t mode);
+extern struct file *file_open_name(struct filename *, int, umode_t);
+extern struct file *filp_open(const char *, int, umode_t);
+extern struct file *file_open_root(struct dentry *, struct vfsmount *,
+ const char *, int, umode_t);
+extern struct file * dentry_open(const struct path *, int, const struct cred *);
+extern struct file * open_with_fake_path(const struct path *, int,
+ struct inode*, const struct cred *);
+static inline struct file *file_clone_open(struct file *file)
+{
+ return dentry_open(&file->f_path, file->f_flags, file->f_cred);
+}
+extern int filp_close(struct file *, fl_owner_t id);
+
+extern struct filename *getname_flags(const char __user *, int, int *);
+extern struct filename *getname(const char __user *);
+extern struct filename *getname_kernel(const char *);
+extern void putname(struct filename *name);
+
+extern int finish_open(struct file *file, struct dentry *dentry,
+ int (*open)(struct inode *, struct file *));
+extern int finish_no_open(struct file *file, struct dentry *dentry);
+
+/* fs/ioctl.c */
+
+extern int ioctl_preallocate(struct file *filp, void __user *argp);
+
+/* fs/dcache.c */
+extern void __init vfs_caches_init_early(void);
+extern void __init vfs_caches_init(void);
+
+extern struct kmem_cache *names_cachep;
+
+#define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
+#define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
+
+#ifdef CONFIG_BLOCK
+extern int register_blkdev(unsigned int, const char *);
+extern void unregister_blkdev(unsigned int, const char *);
+extern void bdev_unhash_inode(dev_t dev);
+extern struct block_device *bdget(dev_t);
+extern struct block_device *bdgrab(struct block_device *bdev);
+extern void bd_set_size(struct block_device *, loff_t size);
+extern void bd_forget(struct inode *inode);
+extern void bdput(struct block_device *);
+extern void invalidate_bdev(struct block_device *);
+extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
+extern int sync_blockdev(struct block_device *bdev);
+extern void kill_bdev(struct block_device *);
+extern struct super_block *freeze_bdev(struct block_device *);
+extern void emergency_thaw_all(void);
+extern void emergency_thaw_bdev(struct super_block *sb);
+extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
+extern int fsync_bdev(struct block_device *);
+
+extern struct super_block *blockdev_superblock;
+
+static inline bool sb_is_blkdev_sb(struct super_block *sb)
+{
+ return sb == blockdev_superblock;
+}
+#else
+static inline void bd_forget(struct inode *inode) {}
+static inline int sync_blockdev(struct block_device *bdev) { return 0; }
+static inline void kill_bdev(struct block_device *bdev) {}
+static inline void invalidate_bdev(struct block_device *bdev) {}
+
+static inline struct super_block *freeze_bdev(struct block_device *sb)
+{
+ return NULL;
+}
+
+static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
+{
+ return 0;
+}
+
+static inline int emergency_thaw_bdev(struct super_block *sb)
+{
+ return 0;
+}
+
+static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
+{
+}
+
+static inline bool sb_is_blkdev_sb(struct super_block *sb)
+{
+ return false;
+}
+#endif
+extern int sync_filesystem(struct super_block *);
+extern const struct file_operations def_blk_fops;
+extern const struct file_operations def_chr_fops;
+#ifdef CONFIG_BLOCK
+extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
+extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
+extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
+extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
+extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
+ void *holder);
+extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
+ void *holder);
+extern void blkdev_put(struct block_device *bdev, fmode_t mode);
+extern int __blkdev_reread_part(struct block_device *bdev);
+extern int blkdev_reread_part(struct block_device *bdev);
+
+#ifdef CONFIG_SYSFS
+extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
+extern void bd_unlink_disk_holder(struct block_device *bdev,
+ struct gendisk *disk);
+#else
+static inline int bd_link_disk_holder(struct block_device *bdev,
+ struct gendisk *disk)
+{
+ return 0;
+}
+static inline void bd_unlink_disk_holder(struct block_device *bdev,
+ struct gendisk *disk)
+{
+}
+#endif
+#endif
+
+/* fs/char_dev.c */
+#define CHRDEV_MAJOR_MAX 512
+/* Marks the bottom of the first segment of free char majors */
+#define CHRDEV_MAJOR_DYN_END 234
+/* Marks the top and bottom of the second segment of free char majors */
+#define CHRDEV_MAJOR_DYN_EXT_START 511
+#define CHRDEV_MAJOR_DYN_EXT_END 384
+
+extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
+extern int register_chrdev_region(dev_t, unsigned, const char *);
+extern int __register_chrdev(unsigned int major, unsigned int baseminor,
+ unsigned int count, const char *name,
+ const struct file_operations *fops);
+extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
+ unsigned int count, const char *name);
+extern void unregister_chrdev_region(dev_t, unsigned);
+extern void chrdev_show(struct seq_file *,off_t);
+
+static inline int register_chrdev(unsigned int major, const char *name,
+ const struct file_operations *fops)
+{
+ return __register_chrdev(major, 0, 256, name, fops);
+}
+
+static inline void unregister_chrdev(unsigned int major, const char *name)
+{
+ __unregister_chrdev(major, 0, 256, name);
+}
+
+/* fs/block_dev.c */
+#define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
+#define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
+
+#ifdef CONFIG_BLOCK
+#define BLKDEV_MAJOR_MAX 512
+extern const char *__bdevname(dev_t, char *buffer);
+extern const char *bdevname(struct block_device *bdev, char *buffer);
+extern struct block_device *lookup_bdev(const char *);
+extern void blkdev_show(struct seq_file *,off_t);
+
+#else
+#define BLKDEV_MAJOR_MAX 0
+#endif
+
+extern void init_special_inode(struct inode *, umode_t, dev_t);
+
+/* Invalid inode operations -- fs/bad_inode.c */
+extern void make_bad_inode(struct inode *);
+extern bool is_bad_inode(struct inode *);
+
+#ifdef CONFIG_BLOCK
+extern void check_disk_size_change(struct gendisk *disk,
+ struct block_device *bdev, bool verbose);
+extern int revalidate_disk(struct gendisk *);
+extern int check_disk_change(struct block_device *);
+extern int __invalidate_device(struct block_device *, bool);
+extern int invalidate_partition(struct gendisk *, int);
+#endif
+unsigned long invalidate_mapping_pages(struct address_space *mapping,
+ pgoff_t start, pgoff_t end);
+
+static inline void invalidate_remote_inode(struct inode *inode)
+{
+ if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ S_ISLNK(inode->i_mode))
+ invalidate_mapping_pages(inode->i_mapping, 0, -1);
+}
+extern int invalidate_inode_pages2(struct address_space *mapping);
+extern int invalidate_inode_pages2_range(struct address_space *mapping,
+ pgoff_t start, pgoff_t end);
+extern int write_inode_now(struct inode *, int);
+extern int filemap_fdatawrite(struct address_space *);
+extern int filemap_flush(struct address_space *);
+extern int filemap_fdatawait_keep_errors(struct address_space *mapping);
+extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
+ loff_t lend);
+
+static inline int filemap_fdatawait(struct address_space *mapping)
+{
+ return filemap_fdatawait_range(mapping, 0, LLONG_MAX);
+}
+
+extern bool filemap_range_has_page(struct address_space *, loff_t lstart,
+ loff_t lend);
+extern int filemap_write_and_wait(struct address_space *mapping);
+extern int filemap_write_and_wait_range(struct address_space *mapping,
+ loff_t lstart, loff_t lend);
+extern int __filemap_fdatawrite_range(struct address_space *mapping,
+ loff_t start, loff_t end, int sync_mode);
+extern int filemap_fdatawrite_range(struct address_space *mapping,
+ loff_t start, loff_t end);
+extern int filemap_check_errors(struct address_space *mapping);
+extern void __filemap_set_wb_err(struct address_space *mapping, int err);
+
+extern int __must_check file_fdatawait_range(struct file *file, loff_t lstart,
+ loff_t lend);
+extern int __must_check file_check_and_advance_wb_err(struct file *file);
+extern int __must_check file_write_and_wait_range(struct file *file,
+ loff_t start, loff_t end);
+
+static inline int file_write_and_wait(struct file *file)
+{
+ return file_write_and_wait_range(file, 0, LLONG_MAX);
+}
+
+/**
+ * filemap_set_wb_err - set a writeback error on an address_space
+ * @mapping: mapping in which to set writeback error
+ * @err: error to be set in mapping
+ *
+ * When writeback fails in some way, we must record that error so that
+ * userspace can be informed when fsync and the like are called. We endeavor
+ * to report errors on any file that was open at the time of the error. Some
+ * internal callers also need to know when writeback errors have occurred.
+ *
+ * When a writeback error occurs, most filesystems will want to call
+ * filemap_set_wb_err to record the error in the mapping so that it will be
+ * automatically reported whenever fsync is called on the file.
+ */
+static inline void filemap_set_wb_err(struct address_space *mapping, int err)
+{
+ /* Fastpath for common case of no error */
+ if (unlikely(err))
+ __filemap_set_wb_err(mapping, err);
+}
+
+/**
+ * filemap_check_wb_error - has an error occurred since the mark was sampled?
+ * @mapping: mapping to check for writeback errors
+ * @since: previously-sampled errseq_t
+ *
+ * Grab the errseq_t value from the mapping, and see if it has changed "since"
+ * the given value was sampled.
+ *
+ * If it has then report the latest error set, otherwise return 0.
+ */
+static inline int filemap_check_wb_err(struct address_space *mapping,
+ errseq_t since)
+{
+ return errseq_check(&mapping->wb_err, since);
+}
+
+/**
+ * filemap_sample_wb_err - sample the current errseq_t to test for later errors
+ * @mapping: mapping to be sampled
+ *
+ * Writeback errors are always reported relative to a particular sample point
+ * in the past. This function provides those sample points.
+ */
+static inline errseq_t filemap_sample_wb_err(struct address_space *mapping)
+{
+ return errseq_sample(&mapping->wb_err);
+}
+
+extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
+ int datasync);
+extern int vfs_fsync(struct file *file, int datasync);
+
+/*
+ * Sync the bytes written if this was a synchronous write. Expect ki_pos
+ * to already be updated for the write, and will return either the amount
+ * of bytes passed in, or an error if syncing the file failed.
+ */
+static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
+{
+ if (iocb->ki_flags & IOCB_DSYNC) {
+ int ret = vfs_fsync_range(iocb->ki_filp,
+ iocb->ki_pos - count, iocb->ki_pos - 1,
+ (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
+ if (ret)
+ return ret;
+ }
+
+ return count;
+}
+
+extern void emergency_sync(void);
+extern void emergency_remount(void);
+#ifdef CONFIG_BLOCK
+extern sector_t bmap(struct inode *, sector_t);
+#endif
+extern int notify_change(struct dentry *, struct iattr *, struct inode **);
+extern int inode_permission(struct inode *, int);
+extern int generic_permission(struct inode *, int);
+extern int __check_sticky(struct inode *dir, struct inode *inode);
+
+static inline bool execute_ok(struct inode *inode)
+{
+ return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
+}
+
+static inline void file_start_write(struct file *file)
+{
+ if (!S_ISREG(file_inode(file)->i_mode))
+ return;
+ __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
+}
+
+static inline bool file_start_write_trylock(struct file *file)
+{
+ if (!S_ISREG(file_inode(file)->i_mode))
+ return true;
+ return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
+}
+
+static inline void file_end_write(struct file *file)
+{
+ if (!S_ISREG(file_inode(file)->i_mode))
+ return;
+ __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
+}
+
+/*
+ * get_write_access() gets write permission for a file.
+ * put_write_access() releases this write permission.
+ * This is used for regular files.
+ * We cannot support write (and maybe mmap read-write shared) accesses and
+ * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
+ * can have the following values:
+ * 0: no writers, no VM_DENYWRITE mappings
+ * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
+ * > 0: (i_writecount) users are writing to the file.
+ *
+ * Normally we operate on that counter with atomic_{inc,dec} and it's safe
+ * except for the cases where we don't hold i_writecount yet. Then we need to
+ * use {get,deny}_write_access() - these functions check the sign and refuse
+ * to do the change if sign is wrong.
+ */
+static inline int get_write_access(struct inode *inode)
+{
+ return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
+}
+static inline int deny_write_access(struct file *file)
+{
+ struct inode *inode = file_inode(file);
+ return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
+}
+static inline void put_write_access(struct inode * inode)
+{
+ atomic_dec(&inode->i_writecount);
+}
+static inline void allow_write_access(struct file *file)
+{
+ if (file)
+ atomic_inc(&file_inode(file)->i_writecount);
+}
+static inline bool inode_is_open_for_write(const struct inode *inode)
+{
+ return atomic_read(&inode->i_writecount) > 0;
+}
+
+#ifdef CONFIG_IMA
+static inline void i_readcount_dec(struct inode *inode)
+{
+ BUG_ON(!atomic_read(&inode->i_readcount));
+ atomic_dec(&inode->i_readcount);
+}
+static inline void i_readcount_inc(struct inode *inode)
+{
+ atomic_inc(&inode->i_readcount);
+}
+#else
+static inline void i_readcount_dec(struct inode *inode)
+{
+ return;
+}
+static inline void i_readcount_inc(struct inode *inode)
+{
+ return;
+}
+#endif
+extern int do_pipe_flags(int *, int);
+
+#define __kernel_read_file_id(id) \
+ id(UNKNOWN, unknown) \
+ id(FIRMWARE, firmware) \
+ id(FIRMWARE_PREALLOC_BUFFER, firmware) \
+ id(MODULE, kernel-module) \
+ id(KEXEC_IMAGE, kexec-image) \
+ id(KEXEC_INITRAMFS, kexec-initramfs) \
+ id(POLICY, security-policy) \
+ id(X509_CERTIFICATE, x509-certificate) \
+ id(MAX_ID, )
+
+#define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
+#define __fid_stringify(dummy, str) #str,
+
+enum kernel_read_file_id {
+ __kernel_read_file_id(__fid_enumify)
+};
+
+static const char * const kernel_read_file_str[] = {
+ __kernel_read_file_id(__fid_stringify)
+};
+
+static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id)
+{
+ if ((unsigned)id >= READING_MAX_ID)
+ return kernel_read_file_str[READING_UNKNOWN];
+
+ return kernel_read_file_str[id];
+}
+
+extern int kernel_read_file(struct file *, void **, loff_t *, loff_t,
+ enum kernel_read_file_id);
+extern int kernel_read_file_from_path(const char *, void **, loff_t *, loff_t,
+ enum kernel_read_file_id);
+extern int kernel_read_file_from_fd(int, void **, loff_t *, loff_t,
+ enum kernel_read_file_id);
+extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
+extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *);
+extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *);
+extern struct file * open_exec(const char *);
+
+/* fs/dcache.c -- generic fs support functions */
+extern bool is_subdir(struct dentry *, struct dentry *);
+extern bool path_is_under(const struct path *, const struct path *);
+
+extern char *file_path(struct file *, char *, int);
+
+#include <linux/err.h>
+
+/* needed for stackable file system support */
+extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
+
+extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
+
+extern int inode_init_always(struct super_block *, struct inode *);
+extern void inode_init_once(struct inode *);
+extern void address_space_init_once(struct address_space *mapping);
+extern struct inode * igrab(struct inode *);
+extern ino_t iunique(struct super_block *, ino_t);
+extern int inode_needs_sync(struct inode *inode);
+extern int generic_delete_inode(struct inode *inode);
+static inline int generic_drop_inode(struct inode *inode)
+{
+ return !inode->i_nlink || inode_unhashed(inode);
+}
+
+extern struct inode *ilookup5_nowait(struct super_block *sb,
+ unsigned long hashval, int (*test)(struct inode *, void *),
+ void *data);
+extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
+ int (*test)(struct inode *, void *), void *data);
+extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
+
+extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
+ int (*test)(struct inode *, void *),
+ int (*set)(struct inode *, void *),
+ void *data);
+extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
+extern struct inode * iget_locked(struct super_block *, unsigned long);
+extern struct inode *find_inode_nowait(struct super_block *,
+ unsigned long,
+ int (*match)(struct inode *,
+ unsigned long, void *),
+ void *data);
+extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
+extern int insert_inode_locked(struct inode *);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
+#else
+static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
+#endif
+extern void unlock_new_inode(struct inode *);
+extern void discard_new_inode(struct inode *);
+extern unsigned int get_next_ino(void);
+extern void evict_inodes(struct super_block *sb);
+
+extern void __iget(struct inode * inode);
+extern void iget_failed(struct inode *);
+extern void clear_inode(struct inode *);
+extern void __destroy_inode(struct inode *);
+extern struct inode *new_inode_pseudo(struct super_block *sb);
+extern struct inode *new_inode(struct super_block *sb);
+extern void free_inode_nonrcu(struct inode *inode);
+extern int should_remove_suid(struct dentry *);
+extern int file_remove_privs(struct file *);
+
+extern void __insert_inode_hash(struct inode *, unsigned long hashval);
+static inline void insert_inode_hash(struct inode *inode)
+{
+ __insert_inode_hash(inode, inode->i_ino);
+}
+
+extern void __remove_inode_hash(struct inode *);
+static inline void remove_inode_hash(struct inode *inode)
+{
+ if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
+ __remove_inode_hash(inode);
+}
+
+extern void inode_sb_list_add(struct inode *inode);
+
+#ifdef CONFIG_BLOCK
+extern int bdev_read_only(struct block_device *);
+#endif
+extern int set_blocksize(struct block_device *, int);
+extern int sb_set_blocksize(struct super_block *, int);
+extern int sb_min_blocksize(struct super_block *, int);
+
+extern int generic_file_mmap(struct file *, struct vm_area_struct *);
+extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
+extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
+extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
+extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
+extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
+extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
+extern ssize_t generic_perform_write(struct file *, struct iov_iter *, loff_t);
+
+ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
+ rwf_t flags);
+ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
+ rwf_t flags);
+
+/* fs/block_dev.c */
+extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);
+extern ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from);
+extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
+ int datasync);
+extern void block_sync_page(struct page *page);
+
+/* fs/splice.c */
+extern ssize_t generic_file_splice_read(struct file *, loff_t *,
+ struct pipe_inode_info *, size_t, unsigned int);
+extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
+ struct file *, loff_t *, size_t, unsigned int);
+extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
+ struct file *out, loff_t *, size_t len, unsigned int flags);
+extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len, unsigned int flags);
+
+
+extern void
+file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
+extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
+extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
+extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
+extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
+extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
+ int whence, loff_t maxsize, loff_t eof);
+extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
+ int whence, loff_t size);
+extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
+extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
+extern int generic_file_open(struct inode * inode, struct file * filp);
+extern int nonseekable_open(struct inode * inode, struct file * filp);
+
+#ifdef CONFIG_BLOCK
+typedef void (dio_submit_t)(struct bio *bio, struct inode *inode,
+ loff_t file_offset);
+
+enum {
+ /* need locking between buffered and direct access */
+ DIO_LOCKING = 0x01,
+
+ /* filesystem does not support filling holes */
+ DIO_SKIP_HOLES = 0x02,
+};
+
+void dio_end_io(struct bio *bio);
+void dio_warn_stale_pagecache(struct file *filp);
+
+ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
+ struct block_device *bdev, struct iov_iter *iter,
+ get_block_t get_block,
+ dio_iodone_t end_io, dio_submit_t submit_io,
+ int flags);
+
+static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
+ struct inode *inode,
+ struct iov_iter *iter,
+ get_block_t get_block)
+{
+ return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
+ get_block, NULL, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
+}
+#endif
+
+void inode_dio_wait(struct inode *inode);
+
+/*
+ * inode_dio_begin - signal start of a direct I/O requests
+ * @inode: inode the direct I/O happens on
+ *
+ * This is called once we've finished processing a direct I/O request,
+ * and is used to wake up callers waiting for direct I/O to be quiesced.
+ */
+static inline void inode_dio_begin(struct inode *inode)
+{
+ atomic_inc(&inode->i_dio_count);
+}
+
+/*
+ * inode_dio_end - signal finish of a direct I/O requests
+ * @inode: inode the direct I/O happens on
+ *
+ * This is called once we've finished processing a direct I/O request,
+ * and is used to wake up callers waiting for direct I/O to be quiesced.
+ */
+static inline void inode_dio_end(struct inode *inode)
+{
+ if (atomic_dec_and_test(&inode->i_dio_count))
+ wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
+}
+
+extern void inode_set_flags(struct inode *inode, unsigned int flags,
+ unsigned int mask);
+
+extern const struct file_operations generic_ro_fops;
+
+#define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
+
+extern int readlink_copy(char __user *, int, const char *);
+extern int page_readlink(struct dentry *, char __user *, int);
+extern const char *page_get_link(struct dentry *, struct inode *,
+ struct delayed_call *);
+extern void page_put_link(void *);
+extern int __page_symlink(struct inode *inode, const char *symname, int len,
+ int nofs);
+extern int page_symlink(struct inode *inode, const char *symname, int len);
+extern const struct inode_operations page_symlink_inode_operations;
+extern void kfree_link(void *);
+extern void generic_fillattr(struct inode *, struct kstat *);
+extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
+extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
+void __inode_add_bytes(struct inode *inode, loff_t bytes);
+void inode_add_bytes(struct inode *inode, loff_t bytes);
+void __inode_sub_bytes(struct inode *inode, loff_t bytes);
+void inode_sub_bytes(struct inode *inode, loff_t bytes);
+static inline loff_t __inode_get_bytes(struct inode *inode)
+{
+ return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
+}
+loff_t inode_get_bytes(struct inode *inode);
+void inode_set_bytes(struct inode *inode, loff_t bytes);
+const char *simple_get_link(struct dentry *, struct inode *,
+ struct delayed_call *);
+extern const struct inode_operations simple_symlink_inode_operations;
+
+extern int iterate_dir(struct file *, struct dir_context *);
+
+extern int vfs_statx(int, const char __user *, int, struct kstat *, u32);
+extern int vfs_statx_fd(unsigned int, struct kstat *, u32, unsigned int);
+
+static inline int vfs_stat(const char __user *filename, struct kstat *stat)
+{
+ return vfs_statx(AT_FDCWD, filename, AT_NO_AUTOMOUNT,
+ stat, STATX_BASIC_STATS);
+}
+static inline int vfs_lstat(const char __user *name, struct kstat *stat)
+{
+ return vfs_statx(AT_FDCWD, name, AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT,
+ stat, STATX_BASIC_STATS);
+}
+static inline int vfs_fstatat(int dfd, const char __user *filename,
+ struct kstat *stat, int flags)
+{
+ return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
+ stat, STATX_BASIC_STATS);
+}
+static inline int vfs_fstat(int fd, struct kstat *stat)
+{
+ return vfs_statx_fd(fd, stat, STATX_BASIC_STATS, 0);
+}
+
+
+extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
+extern int vfs_readlink(struct dentry *, char __user *, int);
+
+extern int __generic_block_fiemap(struct inode *inode,
+ struct fiemap_extent_info *fieinfo,
+ loff_t start, loff_t len,
+ get_block_t *get_block);
+extern int generic_block_fiemap(struct inode *inode,
+ struct fiemap_extent_info *fieinfo, u64 start,
+ u64 len, get_block_t *get_block);
+
+extern struct file_system_type *get_filesystem(struct file_system_type *fs);
+extern void put_filesystem(struct file_system_type *fs);
+extern struct file_system_type *get_fs_type(const char *name);
+extern struct super_block *get_super(struct block_device *);
+extern struct super_block *get_super_thawed(struct block_device *);
+extern struct super_block *get_super_exclusive_thawed(struct block_device *bdev);
+extern struct super_block *get_active_super(struct block_device *bdev);
+extern void drop_super(struct super_block *sb);
+extern void drop_super_exclusive(struct super_block *sb);
+extern void iterate_supers(void (*)(struct super_block *, void *), void *);
+extern void iterate_supers_type(struct file_system_type *,
+ void (*)(struct super_block *, void *), void *);
+
+extern int dcache_dir_open(struct inode *, struct file *);
+extern int dcache_dir_close(struct inode *, struct file *);
+extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
+extern int dcache_readdir(struct file *, struct dir_context *);
+extern int simple_setattr(struct dentry *, struct iattr *);
+extern int simple_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int simple_statfs(struct dentry *, struct kstatfs *);
+extern int simple_open(struct inode *inode, struct file *file);
+extern int simple_link(struct dentry *, struct inode *, struct dentry *);
+extern int simple_unlink(struct inode *, struct dentry *);
+extern int simple_rmdir(struct inode *, struct dentry *);
+extern int simple_rename(struct inode *, struct dentry *,
+ struct inode *, struct dentry *, unsigned int);
+extern int noop_fsync(struct file *, loff_t, loff_t, int);
+extern int noop_set_page_dirty(struct page *page);
+extern void noop_invalidatepage(struct page *page, unsigned int offset,
+ unsigned int length);
+extern ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
+extern int simple_empty(struct dentry *);
+extern int simple_readpage(struct file *file, struct page *page);
+extern int simple_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata);
+extern int simple_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata);
+extern int always_delete_dentry(const struct dentry *);
+extern struct inode *alloc_anon_inode(struct super_block *);
+extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
+extern const struct dentry_operations simple_dentry_operations;
+
+extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
+extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
+extern const struct file_operations simple_dir_operations;
+extern const struct inode_operations simple_dir_inode_operations;
+extern void make_empty_dir_inode(struct inode *inode);
+extern bool is_empty_dir_inode(struct inode *inode);
+struct tree_descr { const char *name; const struct file_operations *ops; int mode; };
+struct dentry *d_alloc_name(struct dentry *, const char *);
+extern int simple_fill_super(struct super_block *, unsigned long,
+ const struct tree_descr *);
+extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
+extern void simple_release_fs(struct vfsmount **mount, int *count);
+
+extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
+ loff_t *ppos, const void *from, size_t available);
+extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
+ const void __user *from, size_t count);
+
+extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
+extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
+
+extern int generic_check_addressable(unsigned, u64);
+
+#ifdef CONFIG_MIGRATION
+extern int buffer_migrate_page(struct address_space *,
+ struct page *, struct page *,
+ enum migrate_mode);
+#else
+#define buffer_migrate_page NULL
+#endif
+
+extern int setattr_prepare(struct dentry *, struct iattr *);
+extern int inode_newsize_ok(const struct inode *, loff_t offset);
+extern void setattr_copy(struct inode *inode, const struct iattr *attr);
+
+extern int file_update_time(struct file *file);
+
+static inline bool io_is_direct(struct file *filp)
+{
+ return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);
+}
+
+static inline bool vma_is_dax(struct vm_area_struct *vma)
+{
+ return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
+}
+
+static inline bool vma_is_fsdax(struct vm_area_struct *vma)
+{
+ struct inode *inode;
+
+ if (!vma->vm_file)
+ return false;
+ if (!vma_is_dax(vma))
+ return false;
+ inode = file_inode(vma->vm_file);
+ if (S_ISCHR(inode->i_mode))
+ return false; /* device-dax */
+ return true;
+}
+
+static inline int iocb_flags(struct file *file)
+{
+ int res = 0;
+ if (file->f_flags & O_APPEND)
+ res |= IOCB_APPEND;
+ if (io_is_direct(file))
+ res |= IOCB_DIRECT;
+ if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
+ res |= IOCB_DSYNC;
+ if (file->f_flags & __O_SYNC)
+ res |= IOCB_SYNC;
+ return res;
+}
+
+static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
+{
+ if (unlikely(flags & ~RWF_SUPPORTED))
+ return -EOPNOTSUPP;
+
+ if (flags & RWF_NOWAIT) {
+ if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
+ return -EOPNOTSUPP;
+ ki->ki_flags |= IOCB_NOWAIT;
+ }
+ if (flags & RWF_HIPRI)
+ ki->ki_flags |= IOCB_HIPRI;
+ if (flags & RWF_DSYNC)
+ ki->ki_flags |= IOCB_DSYNC;
+ if (flags & RWF_SYNC)
+ ki->ki_flags |= (IOCB_DSYNC | IOCB_SYNC);
+ if (flags & RWF_APPEND)
+ ki->ki_flags |= IOCB_APPEND;
+ return 0;
+}
+
+static inline ino_t parent_ino(struct dentry *dentry)
+{
+ ino_t res;
+
+ /*
+ * Don't strictly need d_lock here? If the parent ino could change
+ * then surely we'd have a deeper race in the caller?
+ */
+ spin_lock(&dentry->d_lock);
+ res = dentry->d_parent->d_inode->i_ino;
+ spin_unlock(&dentry->d_lock);
+ return res;
+}
+
+/* Transaction based IO helpers */
+
+/*
+ * An argresp is stored in an allocated page and holds the
+ * size of the argument or response, along with its content
+ */
+struct simple_transaction_argresp {
+ ssize_t size;
+ char data[0];
+};
+
+#define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
+
+char *simple_transaction_get(struct file *file, const char __user *buf,
+ size_t size);
+ssize_t simple_transaction_read(struct file *file, char __user *buf,
+ size_t size, loff_t *pos);
+int simple_transaction_release(struct inode *inode, struct file *file);
+
+void simple_transaction_set(struct file *file, size_t n);
+
+/*
+ * simple attribute files
+ *
+ * These attributes behave similar to those in sysfs:
+ *
+ * Writing to an attribute immediately sets a value, an open file can be
+ * written to multiple times.
+ *
+ * Reading from an attribute creates a buffer from the value that might get
+ * read with multiple read calls. When the attribute has been read
+ * completely, no further read calls are possible until the file is opened
+ * again.
+ *
+ * All attributes contain a text representation of a numeric value
+ * that are accessed with the get() and set() functions.
+ */
+#define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
+static int __fops ## _open(struct inode *inode, struct file *file) \
+{ \
+ __simple_attr_check_format(__fmt, 0ull); \
+ return simple_attr_open(inode, file, __get, __set, __fmt); \
+} \
+static const struct file_operations __fops = { \
+ .owner = THIS_MODULE, \
+ .open = __fops ## _open, \
+ .release = simple_attr_release, \
+ .read = simple_attr_read, \
+ .write = simple_attr_write, \
+ .llseek = generic_file_llseek, \
+}
+
+static inline __printf(1, 2)
+void __simple_attr_check_format(const char *fmt, ...)
+{
+ /* don't do anything, just let the compiler check the arguments; */
+}
+
+int simple_attr_open(struct inode *inode, struct file *file,
+ int (*get)(void *, u64 *), int (*set)(void *, u64),
+ const char *fmt);
+int simple_attr_release(struct inode *inode, struct file *file);
+ssize_t simple_attr_read(struct file *file, char __user *buf,
+ size_t len, loff_t *ppos);
+ssize_t simple_attr_write(struct file *file, const char __user *buf,
+ size_t len, loff_t *ppos);
+
+struct ctl_table;
+int proc_nr_files(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+int proc_nr_dentry(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+int proc_nr_inodes(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+int __init get_filesystem_list(char *buf);
+
+#define __FMODE_EXEC ((__force int) FMODE_EXEC)
+#define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
+
+#define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
+#define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
+ (flag & __FMODE_NONOTIFY)))
+
+static inline bool is_sxid(umode_t mode)
+{
+ return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
+}
+
+static inline int check_sticky(struct inode *dir, struct inode *inode)
+{
+ if (!(dir->i_mode & S_ISVTX))
+ return 0;
+
+ return __check_sticky(dir, inode);
+}
+
+static inline void inode_has_no_xattr(struct inode *inode)
+{
+ if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & SB_NOSEC))
+ inode->i_flags |= S_NOSEC;
+}
+
+static inline bool is_root_inode(struct inode *inode)
+{
+ return inode == inode->i_sb->s_root->d_inode;
+}
+
+static inline bool dir_emit(struct dir_context *ctx,
+ const char *name, int namelen,
+ u64 ino, unsigned type)
+{
+ return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
+}
+static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
+{
+ return ctx->actor(ctx, ".", 1, ctx->pos,
+ file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
+}
+static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
+{
+ return ctx->actor(ctx, "..", 2, ctx->pos,
+ parent_ino(file->f_path.dentry), DT_DIR) == 0;
+}
+static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
+{
+ if (ctx->pos == 0) {
+ if (!dir_emit_dot(file, ctx))
+ return false;
+ ctx->pos = 1;
+ }
+ if (ctx->pos == 1) {
+ if (!dir_emit_dotdot(file, ctx))
+ return false;
+ ctx->pos = 2;
+ }
+ return true;
+}
+static inline bool dir_relax(struct inode *inode)
+{
+ inode_unlock(inode);
+ inode_lock(inode);
+ return !IS_DEADDIR(inode);
+}
+
+static inline bool dir_relax_shared(struct inode *inode)
+{
+ inode_unlock_shared(inode);
+ inode_lock_shared(inode);
+ return !IS_DEADDIR(inode);
+}
+
+extern bool path_noexec(const struct path *path);
+extern void inode_nohighmem(struct inode *inode);
+
+/* mm/fadvise.c */
+extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len,
+ int advice);
+
+#endif /* _LINUX_FS_H */