root/include/linux/fs.h

INCLUDED FROM

DEFINITIONS

1. is_sync_kiocb
2. mapping_tagged
3. i_mmap_lock_write
4. i_mmap_unlock_write
5. i_mmap_lock_read
6. i_mmap_unlock_read
7. mapping_mapped
8. mapping_writably_mapped
9. mapping_map_writable
10. mapping_unmap_writable
11. mapping_deny_writable
12. mapping_allow_writable
13. uncached_acl_sentinel
14. is_uncached_acl
15. i_blocksize
16. inode_unhashed
17. inode_fake_hash
18. inode_lock
19. inode_unlock
20. inode_lock_shared
21. inode_unlock_shared
22. inode_trylock
23. inode_trylock_shared
24. inode_is_locked
25. inode_lock_nested
26. inode_lock_shared_nested
27. i_size_read
28. i_size_write
29. iminor
30. imajor
31. ra_has_index
32. get_file
33. fcntl_getlk
34. fcntl_setlk
35. fcntl_getlk64
36. fcntl_setlk64
37. fcntl_setlease
38. fcntl_getlease
39. locks_free_lock_context
40. locks_init_lock
41. locks_copy_conflock
42. locks_copy_lock
43. locks_remove_posix
44. locks_remove_file
45. posix_test_lock
46. posix_lock_file
47. locks_delete_block
48. vfs_test_lock
49. vfs_lock_file
50. vfs_cancel_lock
51. locks_lock_inode_wait
52. __break_lease
53. lease_get_mtime
54. generic_setlease
55. vfs_setlease
56. lease_modify
57. show_fd_locks
58. file_inode
59. file_dentry
60. locks_lock_file_wait
61. i_uid_read
62. i_gid_read
63. i_uid_write
64. i_gid_write
65. sb_end_write
66. sb_end_pagefault
67. sb_end_intwrite
68. sb_start_write
69. sb_start_write_trylock
70. sb_start_pagefault
71. sb_start_intwrite
72. sb_start_intwrite_trylock
73. call_read_iter
74. call_write_iter
75. call_mmap
76. sb_rdonly
77. HAS_UNMAPPED_ID
78. file_write_hint
79. ki_hint_validate
80. init_sync_kiocb
81. mark_inode_dirty
82. mark_inode_dirty_sync
83. inode_inc_link_count
84. inode_dec_link_count
85. file_accessed
86. mount_bdev
87. kill_block_super
88. __mandatory_lock
89. mandatory_lock
90. locks_verify_locked
91. locks_verify_truncate
92. locks_mandatory_locked
93. locks_mandatory_area
94. __mandatory_lock
95. mandatory_lock
96. locks_verify_locked
97. locks_verify_truncate
98. break_lease
99. break_deleg
100. try_break_deleg
101. break_deleg_wait
102. break_layout
103. break_lease
104. break_deleg
105. try_break_deleg
106. break_deleg_wait
107. break_layout
108. file_clone_open
109. sb_is_blkdev_sb
110. bd_forget
111. sync_blockdev
112. kill_bdev
113. invalidate_bdev
114. freeze_bdev
115. thaw_bdev
116. emergency_thaw_bdev
117. iterate_bdevs
118. sb_is_blkdev_sb
119. bd_link_disk_holder
120. bd_unlink_disk_holder
121. register_chrdev
122. unregister_chrdev
123. invalidate_remote_inode
124. filemap_fdatawait
125. file_write_and_wait
126. filemap_set_wb_err
127. filemap_check_wb_err
128. filemap_sample_wb_err
129. filemap_nr_thps
130. filemap_nr_thps_inc
131. filemap_nr_thps_dec
132. generic_write_sync
133. execute_ok
134. file_start_write
135. file_start_write_trylock
136. file_end_write
137. get_write_access
138. deny_write_access
139. put_write_access
140. allow_write_access
141. inode_is_open_for_write
142. i_readcount_dec
143. i_readcount_inc
144. i_readcount_dec
145. i_readcount_inc
146. __kernel_read_file_id
147. kernel_read_file_id_str
148. generic_drop_inode
149. lockdep_annotate_inode_mutex_key
150. insert_inode_hash
151. remove_inode_hash
152. blockdev_direct_IO
153. inode_dio_begin
154. inode_dio_end
155. __inode_get_bytes
156. vfs_stat
157. vfs_lstat
158. vfs_fstatat
159. vfs_fstat
160. io_is_direct
161. vma_is_dax
162. vma_is_fsdax
163. iocb_flags
164. kiocb_set_rw_flags
165. parent_ino
166. __printf
167. is_sxid
168. check_sticky
169. inode_has_no_xattr
170. is_root_inode
171. dir_emit
172. dir_emit_dot
173. dir_emit_dotdot
174. dir_emit_dots
175. dir_relax
176. dir_relax_shared
177. io_uring_get_socket
178. simple_fill_fsxattr
179. inode_drain_writes

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_FS_H
   3 #define _LINUX_FS_H
   4 
   5 #include <linux/linkage.h>
   6 #include <linux/wait_bit.h>
   7 #include <linux/kdev_t.h>
   8 #include <linux/dcache.h>
   9 #include <linux/path.h>
  10 #include <linux/stat.h>
  11 #include <linux/cache.h>
  12 #include <linux/list.h>
  13 #include <linux/list_lru.h>
  14 #include <linux/llist.h>
  15 #include <linux/radix-tree.h>
  16 #include <linux/xarray.h>
  17 #include <linux/rbtree.h>
  18 #include <linux/init.h>
  19 #include <linux/pid.h>
  20 #include <linux/bug.h>
  21 #include <linux/mutex.h>
  22 #include <linux/rwsem.h>
  23 #include <linux/mm_types.h>
  24 #include <linux/capability.h>
  25 #include <linux/semaphore.h>
  26 #include <linux/fcntl.h>
  27 #include <linux/fiemap.h>
  28 #include <linux/rculist_bl.h>
  29 #include <linux/atomic.h>
  30 #include <linux/shrinker.h>
  31 #include <linux/migrate_mode.h>
  32 #include <linux/uidgid.h>
  33 #include <linux/lockdep.h>
  34 #include <linux/percpu-rwsem.h>
  35 #include <linux/workqueue.h>
  36 #include <linux/delayed_call.h>
  37 #include <linux/uuid.h>
  38 #include <linux/errseq.h>
  39 #include <linux/ioprio.h>
  40 #include <linux/fs_types.h>
  41 #include <linux/build_bug.h>
  42 #include <linux/stddef.h>
  43 
  44 #include <asm/byteorder.h>
  45 #include <uapi/linux/fs.h>
  46 
  47 struct backing_dev_info;
  48 struct bdi_writeback;
  49 struct bio;
  50 struct export_operations;
  51 struct hd_geometry;
  52 struct iovec;
  53 struct kiocb;
  54 struct kobject;
  55 struct pipe_inode_info;
  56 struct poll_table_struct;
  57 struct kstatfs;
  58 struct vm_area_struct;
  59 struct vfsmount;
  60 struct cred;
  61 struct swap_info_struct;
  62 struct seq_file;
  63 struct workqueue_struct;
  64 struct iov_iter;
  65 struct fscrypt_info;
  66 struct fscrypt_operations;
  67 struct fsverity_info;
  68 struct fsverity_operations;
  69 struct fs_context;
  70 struct fs_parameter_description;
  71 
  72 extern void __init inode_init(void);
  73 extern void __init inode_init_early(void);
  74 extern void __init files_init(void);
  75 extern void __init files_maxfiles_init(void);
  76 
  77 extern struct files_stat_struct files_stat;
  78 extern unsigned long get_max_files(void);
  79 extern unsigned int sysctl_nr_open;
  80 extern struct inodes_stat_t inodes_stat;
  81 extern int leases_enable, lease_break_time;
  82 extern int sysctl_protected_symlinks;
  83 extern int sysctl_protected_hardlinks;
  84 extern int sysctl_protected_fifos;
  85 extern int sysctl_protected_regular;
  86 
  87 typedef __kernel_rwf_t rwf_t;
  88 
  89 struct buffer_head;
  90 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
  91                         struct buffer_head *bh_result, int create);
  92 typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
  93                         ssize_t bytes, void *private);
  94 
  95 #define MAY_EXEC                0x00000001
  96 #define MAY_WRITE               0x00000002
  97 #define MAY_READ                0x00000004
  98 #define MAY_APPEND              0x00000008
  99 #define MAY_ACCESS              0x00000010
 100 #define MAY_OPEN                0x00000020
 101 #define MAY_CHDIR               0x00000040
 102 /* called from RCU mode, don't block */
 103 #define MAY_NOT_BLOCK           0x00000080
 104 
 105 /*
 106  * flags in file.f_mode.  Note that FMODE_READ and FMODE_WRITE must correspond
 107  * to O_WRONLY and O_RDWR via the strange trick in do_dentry_open()
 108  */
 109 
 110 /* file is open for reading */
 111 #define FMODE_READ              ((__force fmode_t)0x1)
 112 /* file is open for writing */
 113 #define FMODE_WRITE             ((__force fmode_t)0x2)
 114 /* file is seekable */
 115 #define FMODE_LSEEK             ((__force fmode_t)0x4)
 116 /* file can be accessed using pread */
 117 #define FMODE_PREAD             ((__force fmode_t)0x8)
 118 /* file can be accessed using pwrite */
 119 #define FMODE_PWRITE            ((__force fmode_t)0x10)
 120 /* File is opened for execution with sys_execve / sys_uselib */
 121 #define FMODE_EXEC              ((__force fmode_t)0x20)
 122 /* File is opened with O_NDELAY (only set for block devices) */
 123 #define FMODE_NDELAY            ((__force fmode_t)0x40)
 124 /* File is opened with O_EXCL (only set for block devices) */
 125 #define FMODE_EXCL              ((__force fmode_t)0x80)
 126 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
 127    (specialy hack for floppy.c) */
 128 #define FMODE_WRITE_IOCTL       ((__force fmode_t)0x100)
 129 /* 32bit hashes as llseek() offset (for directories) */
 130 #define FMODE_32BITHASH         ((__force fmode_t)0x200)
 131 /* 64bit hashes as llseek() offset (for directories) */
 132 #define FMODE_64BITHASH         ((__force fmode_t)0x400)
 133 
 134 /*
 135  * Don't update ctime and mtime.
 136  *
 137  * Currently a special hack for the XFS open_by_handle ioctl, but we'll
 138  * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
 139  */
 140 #define FMODE_NOCMTIME          ((__force fmode_t)0x800)
 141 
 142 /* Expect random access pattern */
 143 #define FMODE_RANDOM            ((__force fmode_t)0x1000)
 144 
 145 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
 146 #define FMODE_UNSIGNED_OFFSET   ((__force fmode_t)0x2000)
 147 
 148 /* File is opened with O_PATH; almost nothing can be done with it */
 149 #define FMODE_PATH              ((__force fmode_t)0x4000)
 150 
 151 /* File needs atomic accesses to f_pos */
 152 #define FMODE_ATOMIC_POS        ((__force fmode_t)0x8000)
 153 /* Write access to underlying fs */
 154 #define FMODE_WRITER            ((__force fmode_t)0x10000)
 155 /* Has read method(s) */
 156 #define FMODE_CAN_READ          ((__force fmode_t)0x20000)
 157 /* Has write method(s) */
 158 #define FMODE_CAN_WRITE         ((__force fmode_t)0x40000)
 159 
 160 #define FMODE_OPENED            ((__force fmode_t)0x80000)
 161 #define FMODE_CREATED           ((__force fmode_t)0x100000)
 162 
 163 /* File is stream-like */
 164 #define FMODE_STREAM            ((__force fmode_t)0x200000)
 165 
 166 /* File was opened by fanotify and shouldn't generate fanotify events */
 167 #define FMODE_NONOTIFY          ((__force fmode_t)0x4000000)
 168 
 169 /* File is capable of returning -EAGAIN if I/O will block */
 170 #define FMODE_NOWAIT            ((__force fmode_t)0x8000000)
 171 
 172 /* File represents mount that needs unmounting */
 173 #define FMODE_NEED_UNMOUNT      ((__force fmode_t)0x10000000)
 174 
 175 /* File does not contribute to nr_files count */
 176 #define FMODE_NOACCOUNT         ((__force fmode_t)0x20000000)
 177 
 178 /*
 179  * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
 180  * that indicates that they should check the contents of the iovec are
 181  * valid, but not check the memory that the iovec elements
 182  * points too.
 183  */
 184 #define CHECK_IOVEC_ONLY -1
 185 
 186 /*
 187  * Attribute flags.  These should be or-ed together to figure out what
 188  * has been changed!
 189  */
 190 #define ATTR_MODE       (1 << 0)
 191 #define ATTR_UID        (1 << 1)
 192 #define ATTR_GID        (1 << 2)
 193 #define ATTR_SIZE       (1 << 3)
 194 #define ATTR_ATIME      (1 << 4)
 195 #define ATTR_MTIME      (1 << 5)
 196 #define ATTR_CTIME      (1 << 6)
 197 #define ATTR_ATIME_SET  (1 << 7)
 198 #define ATTR_MTIME_SET  (1 << 8)
 199 #define ATTR_FORCE      (1 << 9) /* Not a change, but a change it */
 200 #define ATTR_KILL_SUID  (1 << 11)
 201 #define ATTR_KILL_SGID  (1 << 12)
 202 #define ATTR_FILE       (1 << 13)
 203 #define ATTR_KILL_PRIV  (1 << 14)
 204 #define ATTR_OPEN       (1 << 15) /* Truncating from open(O_TRUNC) */
 205 #define ATTR_TIMES_SET  (1 << 16)
 206 #define ATTR_TOUCH      (1 << 17)
 207 
 208 /*
 209  * Whiteout is represented by a char device.  The following constants define the
 210  * mode and device number to use.
 211  */
 212 #define WHITEOUT_MODE 0
 213 #define WHITEOUT_DEV 0
 214 
 215 /*
 216  * This is the Inode Attributes structure, used for notify_change().  It
 217  * uses the above definitions as flags, to know which values have changed.
 218  * Also, in this manner, a Filesystem can look at only the values it cares
 219  * about.  Basically, these are the attributes that the VFS layer can
 220  * request to change from the FS layer.
 221  *
 222  * Derek Atkins <warlord@MIT.EDU> 94-10-20
 223  */
 224 struct iattr {
 225         unsigned int    ia_valid;
 226         umode_t         ia_mode;
 227         kuid_t          ia_uid;
 228         kgid_t          ia_gid;
 229         loff_t          ia_size;
 230         struct timespec64 ia_atime;
 231         struct timespec64 ia_mtime;
 232         struct timespec64 ia_ctime;
 233 
 234         /*
 235          * Not an attribute, but an auxiliary info for filesystems wanting to
 236          * implement an ftruncate() like method.  NOTE: filesystem should
 237          * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
 238          */
 239         struct file     *ia_file;
 240 };
 241 
 242 /*
 243  * Includes for diskquotas.
 244  */
 245 #include <linux/quota.h>
 246 
 247 /*
 248  * Maximum number of layers of fs stack.  Needs to be limited to
 249  * prevent kernel stack overflow
 250  */
 251 #define FILESYSTEM_MAX_STACK_DEPTH 2
 252 
 253 /** 
 254  * enum positive_aop_returns - aop return codes with specific semantics
 255  *
 256  * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
 257  *                          completed, that the page is still locked, and
 258  *                          should be considered active.  The VM uses this hint
 259  *                          to return the page to the active list -- it won't
 260  *                          be a candidate for writeback again in the near
 261  *                          future.  Other callers must be careful to unlock
 262  *                          the page if they get this return.  Returned by
 263  *                          writepage(); 
 264  *
 265  * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
 266  *                      unlocked it and the page might have been truncated.
 267  *                      The caller should back up to acquiring a new page and
 268  *                      trying again.  The aop will be taking reasonable
 269  *                      precautions not to livelock.  If the caller held a page
 270  *                      reference, it should drop it before retrying.  Returned
 271  *                      by readpage().
 272  *
 273  * address_space_operation functions return these large constants to indicate
 274  * special semantics to the caller.  These are much larger than the bytes in a
 275  * page to allow for functions that return the number of bytes operated on in a
 276  * given page.
 277  */
 278 
 279 enum positive_aop_returns {
 280         AOP_WRITEPAGE_ACTIVATE  = 0x80000,
 281         AOP_TRUNCATED_PAGE      = 0x80001,
 282 };
 283 
 284 #define AOP_FLAG_CONT_EXPAND            0x0001 /* called from cont_expand */
 285 #define AOP_FLAG_NOFS                   0x0002 /* used by filesystem to direct
 286                                                 * helper code (eg buffer layer)
 287                                                 * to clear GFP_FS from alloc */
 288 
 289 /*
 290  * oh the beauties of C type declarations.
 291  */
 292 struct page;
 293 struct address_space;
 294 struct writeback_control;
 295 
 296 /*
 297  * Write life time hint values.
 298  * Stored in struct inode as u8.
 299  */
 300 enum rw_hint {
 301         WRITE_LIFE_NOT_SET      = 0,
 302         WRITE_LIFE_NONE         = RWH_WRITE_LIFE_NONE,
 303         WRITE_LIFE_SHORT        = RWH_WRITE_LIFE_SHORT,
 304         WRITE_LIFE_MEDIUM       = RWH_WRITE_LIFE_MEDIUM,
 305         WRITE_LIFE_LONG         = RWH_WRITE_LIFE_LONG,
 306         WRITE_LIFE_EXTREME      = RWH_WRITE_LIFE_EXTREME,
 307 };
 308 
 309 #define IOCB_EVENTFD            (1 << 0)
 310 #define IOCB_APPEND             (1 << 1)
 311 #define IOCB_DIRECT             (1 << 2)
 312 #define IOCB_HIPRI              (1 << 3)
 313 #define IOCB_DSYNC              (1 << 4)
 314 #define IOCB_SYNC               (1 << 5)
 315 #define IOCB_WRITE              (1 << 6)
 316 #define IOCB_NOWAIT             (1 << 7)
 317 
 318 struct kiocb {
 319         struct file             *ki_filp;
 320 
 321         /* The 'ki_filp' pointer is shared in a union for aio */
 322         randomized_struct_fields_start
 323 
 324         loff_t                  ki_pos;
 325         void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
 326         void                    *private;
 327         int                     ki_flags;
 328         u16                     ki_hint;
 329         u16                     ki_ioprio; /* See linux/ioprio.h */
 330         unsigned int            ki_cookie; /* for ->iopoll */
 331 
 332         randomized_struct_fields_end
 333 };
 334 
 335 static inline bool is_sync_kiocb(struct kiocb *kiocb)
 336 {
 337         return kiocb->ki_complete == NULL;
 338 }
 339 
 340 /*
 341  * "descriptor" for what we're up to with a read.
 342  * This allows us to use the same read code yet
 343  * have multiple different users of the data that
 344  * we read from a file.
 345  *
 346  * The simplest case just copies the data to user
 347  * mode.
 348  */
 349 typedef struct {
 350         size_t written;
 351         size_t count;
 352         union {
 353                 char __user *buf;
 354                 void *data;
 355         } arg;
 356         int error;
 357 } read_descriptor_t;
 358 
 359 typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
 360                 unsigned long, unsigned long);
 361 
 362 struct address_space_operations {
 363         int (*writepage)(struct page *page, struct writeback_control *wbc);
 364         int (*readpage)(struct file *, struct page *);
 365 
 366         /* Write back some dirty pages from this mapping. */
 367         int (*writepages)(struct address_space *, struct writeback_control *);
 368 
 369         /* Set a page dirty.  Return true if this dirtied it */
 370         int (*set_page_dirty)(struct page *page);
 371 
 372         /*
 373          * Reads in the requested pages. Unlike ->readpage(), this is
 374          * PURELY used for read-ahead!.
 375          */
 376         int (*readpages)(struct file *filp, struct address_space *mapping,
 377                         struct list_head *pages, unsigned nr_pages);
 378 
 379         int (*write_begin)(struct file *, struct address_space *mapping,
 380                                 loff_t pos, unsigned len, unsigned flags,
 381                                 struct page **pagep, void **fsdata);
 382         int (*write_end)(struct file *, struct address_space *mapping,
 383                                 loff_t pos, unsigned len, unsigned copied,
 384                                 struct page *page, void *fsdata);
 385 
 386         /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
 387         sector_t (*bmap)(struct address_space *, sector_t);
 388         void (*invalidatepage) (struct page *, unsigned int, unsigned int);
 389         int (*releasepage) (struct page *, gfp_t);
 390         void (*freepage)(struct page *);
 391         ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
 392         /*
 393          * migrate the contents of a page to the specified target. If
 394          * migrate_mode is MIGRATE_ASYNC, it must not block.
 395          */
 396         int (*migratepage) (struct address_space *,
 397                         struct page *, struct page *, enum migrate_mode);
 398         bool (*isolate_page)(struct page *, isolate_mode_t);
 399         void (*putback_page)(struct page *);
 400         int (*launder_page) (struct page *);
 401         int (*is_partially_uptodate) (struct page *, unsigned long,
 402                                         unsigned long);
 403         void (*is_dirty_writeback) (struct page *, bool *, bool *);
 404         int (*error_remove_page)(struct address_space *, struct page *);
 405 
 406         /* swapfile support */
 407         int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
 408                                 sector_t *span);
 409         void (*swap_deactivate)(struct file *file);
 410 };
 411 
 412 extern const struct address_space_operations empty_aops;
 413 
 414 /*
 415  * pagecache_write_begin/pagecache_write_end must be used by general code
 416  * to write into the pagecache.
 417  */
 418 int pagecache_write_begin(struct file *, struct address_space *mapping,
 419                                 loff_t pos, unsigned len, unsigned flags,
 420                                 struct page **pagep, void **fsdata);
 421 
 422 int pagecache_write_end(struct file *, struct address_space *mapping,
 423                                 loff_t pos, unsigned len, unsigned copied,
 424                                 struct page *page, void *fsdata);
 425 
 426 /**
 427  * struct address_space - Contents of a cacheable, mappable object.
 428  * @host: Owner, either the inode or the block_device.
 429  * @i_pages: Cached pages.
 430  * @gfp_mask: Memory allocation flags to use for allocating pages.
 431  * @i_mmap_writable: Number of VM_SHARED mappings.
 432  * @nr_thps: Number of THPs in the pagecache (non-shmem only).
 433  * @i_mmap: Tree of private and shared mappings.
 434  * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
 435  * @nrpages: Number of page entries, protected by the i_pages lock.
 436  * @nrexceptional: Shadow or DAX entries, protected by the i_pages lock.
 437  * @writeback_index: Writeback starts here.
 438  * @a_ops: Methods.
 439  * @flags: Error bits and flags (AS_*).
 440  * @wb_err: The most recent error which has occurred.
 441  * @private_lock: For use by the owner of the address_space.
 442  * @private_list: For use by the owner of the address_space.
 443  * @private_data: For use by the owner of the address_space.
 444  */
 445 struct address_space {
 446         struct inode            *host;
 447         struct xarray           i_pages;
 448         gfp_t                   gfp_mask;
 449         atomic_t                i_mmap_writable;
 450 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
 451         /* number of thp, only for non-shmem files */
 452         atomic_t                nr_thps;
 453 #endif
 454         struct rb_root_cached   i_mmap;
 455         struct rw_semaphore     i_mmap_rwsem;
 456         unsigned long           nrpages;
 457         unsigned long           nrexceptional;
 458         pgoff_t                 writeback_index;
 459         const struct address_space_operations *a_ops;
 460         unsigned long           flags;
 461         errseq_t                wb_err;
 462         spinlock_t              private_lock;
 463         struct list_head        private_list;
 464         void                    *private_data;
 465 } __attribute__((aligned(sizeof(long)))) __randomize_layout;
 466         /*
 467          * On most architectures that alignment is already the case; but
 468          * must be enforced here for CRIS, to let the least significant bit
 469          * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
 470          */
 471 struct request_queue;
 472 
 473 struct block_device {
 474         dev_t                   bd_dev;  /* not a kdev_t - it's a search key */
 475         int                     bd_openers;
 476         struct inode *          bd_inode;       /* will die */
 477         struct super_block *    bd_super;
 478         struct mutex            bd_mutex;       /* open/close mutex */
 479         void *                  bd_claiming;
 480         void *                  bd_holder;
 481         int                     bd_holders;
 482         bool                    bd_write_holder;
 483 #ifdef CONFIG_SYSFS
 484         struct list_head        bd_holder_disks;
 485 #endif
 486         struct block_device *   bd_contains;
 487         unsigned                bd_block_size;
 488         u8                      bd_partno;
 489         struct hd_struct *      bd_part;
 490         /* number of times partitions within this device have been opened. */
 491         unsigned                bd_part_count;
 492         int                     bd_invalidated;
 493         struct gendisk *        bd_disk;
 494         struct request_queue *  bd_queue;
 495         struct backing_dev_info *bd_bdi;
 496         struct list_head        bd_list;
 497         /*
 498          * Private data.  You must have bd_claim'ed the block_device
 499          * to use this.  NOTE:  bd_claim allows an owner to claim
 500          * the same device multiple times, the owner must take special
 501          * care to not mess up bd_private for that case.
 502          */
 503         unsigned long           bd_private;
 504 
 505         /* The counter of freeze processes */
 506         int                     bd_fsfreeze_count;
 507         /* Mutex for freeze */
 508         struct mutex            bd_fsfreeze_mutex;
 509 } __randomize_layout;
 510 
 511 /* XArray tags, for tagging dirty and writeback pages in the pagecache. */
 512 #define PAGECACHE_TAG_DIRTY     XA_MARK_0
 513 #define PAGECACHE_TAG_WRITEBACK XA_MARK_1
 514 #define PAGECACHE_TAG_TOWRITE   XA_MARK_2
 515 
 516 /*
 517  * Returns true if any of the pages in the mapping are marked with the tag.
 518  */
 519 static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
 520 {
 521         return xa_marked(&mapping->i_pages, tag);
 522 }
 523 
 524 static inline void i_mmap_lock_write(struct address_space *mapping)
 525 {
 526         down_write(&mapping->i_mmap_rwsem);
 527 }
 528 
 529 static inline void i_mmap_unlock_write(struct address_space *mapping)
 530 {
 531         up_write(&mapping->i_mmap_rwsem);
 532 }
 533 
 534 static inline void i_mmap_lock_read(struct address_space *mapping)
 535 {
 536         down_read(&mapping->i_mmap_rwsem);
 537 }
 538 
 539 static inline void i_mmap_unlock_read(struct address_space *mapping)
 540 {
 541         up_read(&mapping->i_mmap_rwsem);
 542 }
 543 
 544 /*
 545  * Might pages of this file be mapped into userspace?
 546  */
 547 static inline int mapping_mapped(struct address_space *mapping)
 548 {
 549         return  !RB_EMPTY_ROOT(&mapping->i_mmap.rb_root);
 550 }
 551 
 552 /*
 553  * Might pages of this file have been modified in userspace?
 554  * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
 555  * marks vma as VM_SHARED if it is shared, and the file was opened for
 556  * writing i.e. vma may be mprotected writable even if now readonly.
 557  *
 558  * If i_mmap_writable is negative, no new writable mappings are allowed. You
 559  * can only deny writable mappings, if none exists right now.
 560  */
 561 static inline int mapping_writably_mapped(struct address_space *mapping)
 562 {
 563         return atomic_read(&mapping->i_mmap_writable) > 0;
 564 }
 565 
 566 static inline int mapping_map_writable(struct address_space *mapping)
 567 {
 568         return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
 569                 0 : -EPERM;
 570 }
 571 
 572 static inline void mapping_unmap_writable(struct address_space *mapping)
 573 {
 574         atomic_dec(&mapping->i_mmap_writable);
 575 }
 576 
 577 static inline int mapping_deny_writable(struct address_space *mapping)
 578 {
 579         return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
 580                 0 : -EBUSY;
 581 }
 582 
 583 static inline void mapping_allow_writable(struct address_space *mapping)
 584 {
 585         atomic_inc(&mapping->i_mmap_writable);
 586 }
 587 
 588 /*
 589  * Use sequence counter to get consistent i_size on 32-bit processors.
 590  */
 591 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 592 #include <linux/seqlock.h>
 593 #define __NEED_I_SIZE_ORDERED
 594 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
 595 #else
 596 #define i_size_ordered_init(inode) do { } while (0)
 597 #endif
 598 
 599 struct posix_acl;
 600 #define ACL_NOT_CACHED ((void *)(-1))
 601 #define ACL_DONT_CACHE ((void *)(-3))
 602 
 603 static inline struct posix_acl *
 604 uncached_acl_sentinel(struct task_struct *task)
 605 {
 606         return (void *)task + 1;
 607 }
 608 
 609 static inline bool
 610 is_uncached_acl(struct posix_acl *acl)
 611 {
 612         return (long)acl & 1;
 613 }
 614 
 615 #define IOP_FASTPERM    0x0001
 616 #define IOP_LOOKUP      0x0002
 617 #define IOP_NOFOLLOW    0x0004
 618 #define IOP_XATTR       0x0008
 619 #define IOP_DEFAULT_READLINK    0x0010
 620 
 621 struct fsnotify_mark_connector;
 622 
 623 /*
 624  * Keep mostly read-only and often accessed (especially for
 625  * the RCU path lookup and 'stat' data) fields at the beginning
 626  * of the 'struct inode'
 627  */
 628 struct inode {
 629         umode_t                 i_mode;
 630         unsigned short          i_opflags;
 631         kuid_t                  i_uid;
 632         kgid_t                  i_gid;
 633         unsigned int            i_flags;
 634 
 635 #ifdef CONFIG_FS_POSIX_ACL
 636         struct posix_acl        *i_acl;
 637         struct posix_acl        *i_default_acl;
 638 #endif
 639 
 640         const struct inode_operations   *i_op;
 641         struct super_block      *i_sb;
 642         struct address_space    *i_mapping;
 643 
 644 #ifdef CONFIG_SECURITY
 645         void                    *i_security;
 646 #endif
 647 
 648         /* Stat data, not accessed from path walking */
 649         unsigned long           i_ino;
 650         /*
 651          * Filesystems may only read i_nlink directly.  They shall use the
 652          * following functions for modification:
 653          *
 654          *    (set|clear|inc|drop)_nlink
 655          *    inode_(inc|dec)_link_count
 656          */
 657         union {
 658                 const unsigned int i_nlink;
 659                 unsigned int __i_nlink;
 660         };
 661         dev_t                   i_rdev;
 662         loff_t                  i_size;
 663         struct timespec64       i_atime;
 664         struct timespec64       i_mtime;
 665         struct timespec64       i_ctime;
 666         spinlock_t              i_lock; /* i_blocks, i_bytes, maybe i_size */
 667         unsigned short          i_bytes;
 668         u8                      i_blkbits;
 669         u8                      i_write_hint;
 670         blkcnt_t                i_blocks;
 671 
 672 #ifdef __NEED_I_SIZE_ORDERED
 673         seqcount_t              i_size_seqcount;
 674 #endif
 675 
 676         /* Misc */
 677         unsigned long           i_state;
 678         struct rw_semaphore     i_rwsem;
 679 
 680         unsigned long           dirtied_when;   /* jiffies of first dirtying */
 681         unsigned long           dirtied_time_when;
 682 
 683         struct hlist_node       i_hash;
 684         struct list_head        i_io_list;      /* backing dev IO list */
 685 #ifdef CONFIG_CGROUP_WRITEBACK
 686         struct bdi_writeback    *i_wb;          /* the associated cgroup wb */
 687 
 688         /* foreign inode detection, see wbc_detach_inode() */
 689         int                     i_wb_frn_winner;
 690         u16                     i_wb_frn_avg_time;
 691         u16                     i_wb_frn_history;
 692 #endif
 693         struct list_head        i_lru;          /* inode LRU list */
 694         struct list_head        i_sb_list;
 695         struct list_head        i_wb_list;      /* backing dev writeback list */
 696         union {
 697                 struct hlist_head       i_dentry;
 698                 struct rcu_head         i_rcu;
 699         };
 700         atomic64_t              i_version;
 701         atomic64_t              i_sequence; /* see futex */
 702         atomic_t                i_count;
 703         atomic_t                i_dio_count;
 704         atomic_t                i_writecount;
 705 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
 706         atomic_t                i_readcount; /* struct files open RO */
 707 #endif
 708         union {
 709                 const struct file_operations    *i_fop; /* former ->i_op->default_file_ops */
 710                 void (*free_inode)(struct inode *);
 711         };
 712         struct file_lock_context        *i_flctx;
 713         struct address_space    i_data;
 714         struct list_head        i_devices;
 715         union {
 716                 struct pipe_inode_info  *i_pipe;
 717                 struct block_device     *i_bdev;
 718                 struct cdev             *i_cdev;
 719                 char                    *i_link;
 720                 unsigned                i_dir_seq;
 721         };
 722 
 723         __u32                   i_generation;
 724 
 725 #ifdef CONFIG_FSNOTIFY
 726         __u32                   i_fsnotify_mask; /* all events this inode cares about */
 727         struct fsnotify_mark_connector __rcu    *i_fsnotify_marks;
 728 #endif
 729 
 730 #ifdef CONFIG_FS_ENCRYPTION
 731         struct fscrypt_info     *i_crypt_info;
 732 #endif
 733 
 734 #ifdef CONFIG_FS_VERITY
 735         struct fsverity_info    *i_verity_info;
 736 #endif
 737 
 738         void                    *i_private; /* fs or device private pointer */
 739 } __randomize_layout;
 740 
 741 struct timespec64 timestamp_truncate(struct timespec64 t, struct inode *inode);
 742 
 743 static inline unsigned int i_blocksize(const struct inode *node)
 744 {
 745         return (1 << node->i_blkbits);
 746 }
 747 
 748 static inline int inode_unhashed(struct inode *inode)
 749 {
 750         return hlist_unhashed(&inode->i_hash);
 751 }
 752 
 753 /*
 754  * __mark_inode_dirty expects inodes to be hashed.  Since we don't
 755  * want special inodes in the fileset inode space, we make them
 756  * appear hashed, but do not put on any lists.  hlist_del()
 757  * will work fine and require no locking.
 758  */
 759 static inline void inode_fake_hash(struct inode *inode)
 760 {
 761         hlist_add_fake(&inode->i_hash);
 762 }
 763 
 764 /*
 765  * inode->i_mutex nesting subclasses for the lock validator:
 766  *
 767  * 0: the object of the current VFS operation
 768  * 1: parent
 769  * 2: child/target
 770  * 3: xattr
 771  * 4: second non-directory
 772  * 5: second parent (when locking independent directories in rename)
 773  *
 774  * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
 775  * non-directories at once.
 776  *
 777  * The locking order between these classes is
 778  * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
 779  */
 780 enum inode_i_mutex_lock_class
 781 {
 782         I_MUTEX_NORMAL,
 783         I_MUTEX_PARENT,
 784         I_MUTEX_CHILD,
 785         I_MUTEX_XATTR,
 786         I_MUTEX_NONDIR2,
 787         I_MUTEX_PARENT2,
 788 };
 789 
 790 static inline void inode_lock(struct inode *inode)
 791 {
 792         down_write(&inode->i_rwsem);
 793 }
 794 
 795 static inline void inode_unlock(struct inode *inode)
 796 {
 797         up_write(&inode->i_rwsem);
 798 }
 799 
 800 static inline void inode_lock_shared(struct inode *inode)
 801 {
 802         down_read(&inode->i_rwsem);
 803 }
 804 
 805 static inline void inode_unlock_shared(struct inode *inode)
 806 {
 807         up_read(&inode->i_rwsem);
 808 }
 809 
 810 static inline int inode_trylock(struct inode *inode)
 811 {
 812         return down_write_trylock(&inode->i_rwsem);
 813 }
 814 
 815 static inline int inode_trylock_shared(struct inode *inode)
 816 {
 817         return down_read_trylock(&inode->i_rwsem);
 818 }
 819 
 820 static inline int inode_is_locked(struct inode *inode)
 821 {
 822         return rwsem_is_locked(&inode->i_rwsem);
 823 }
 824 
 825 static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
 826 {
 827         down_write_nested(&inode->i_rwsem, subclass);
 828 }
 829 
 830 static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass)
 831 {
 832         down_read_nested(&inode->i_rwsem, subclass);
 833 }
 834 
 835 void lock_two_nondirectories(struct inode *, struct inode*);
 836 void unlock_two_nondirectories(struct inode *, struct inode*);
 837 
 838 /*
 839  * NOTE: in a 32bit arch with a preemptable kernel and
 840  * an UP compile the i_size_read/write must be atomic
 841  * with respect to the local cpu (unlike with preempt disabled),
 842  * but they don't need to be atomic with respect to other cpus like in
 843  * true SMP (so they need either to either locally disable irq around
 844  * the read or for example on x86 they can be still implemented as a
 845  * cmpxchg8b without the need of the lock prefix). For SMP compiles
 846  * and 64bit archs it makes no difference if preempt is enabled or not.
 847  */
 848 static inline loff_t i_size_read(const struct inode *inode)
 849 {
 850 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 851         loff_t i_size;
 852         unsigned int seq;
 853 
 854         do {
 855                 seq = read_seqcount_begin(&inode->i_size_seqcount);
 856                 i_size = inode->i_size;
 857         } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
 858         return i_size;
 859 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
 860         loff_t i_size;
 861 
 862         preempt_disable();
 863         i_size = inode->i_size;
 864         preempt_enable();
 865         return i_size;
 866 #else
 867         return inode->i_size;
 868 #endif
 869 }
 870 
 871 /*
 872  * NOTE: unlike i_size_read(), i_size_write() does need locking around it
 873  * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
 874  * can be lost, resulting in subsequent i_size_read() calls spinning forever.
 875  */
 876 static inline void i_size_write(struct inode *inode, loff_t i_size)
 877 {
 878 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 879         preempt_disable();
 880         write_seqcount_begin(&inode->i_size_seqcount);
 881         inode->i_size = i_size;
 882         write_seqcount_end(&inode->i_size_seqcount);
 883         preempt_enable();
 884 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
 885         preempt_disable();
 886         inode->i_size = i_size;
 887         preempt_enable();
 888 #else
 889         inode->i_size = i_size;
 890 #endif
 891 }
 892 
 893 static inline unsigned iminor(const struct inode *inode)
 894 {
 895         return MINOR(inode->i_rdev);
 896 }
 897 
 898 static inline unsigned imajor(const struct inode *inode)
 899 {
 900         return MAJOR(inode->i_rdev);
 901 }
 902 
 903 extern struct block_device *I_BDEV(struct inode *inode);
 904 
 905 struct fown_struct {
 906         rwlock_t lock;          /* protects pid, uid, euid fields */
 907         struct pid *pid;        /* pid or -pgrp where SIGIO should be sent */
 908         enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
 909         kuid_t uid, euid;       /* uid/euid of process setting the owner */
 910         int signum;             /* posix.1b rt signal to be delivered on IO */
 911 };
 912 
 913 /*
 914  * Track a single file's readahead state
 915  */
 916 struct file_ra_state {
 917         pgoff_t start;                  /* where readahead started */
 918         unsigned int size;              /* # of readahead pages */
 919         unsigned int async_size;        /* do asynchronous readahead when
 920                                            there are only # of pages ahead */
 921 
 922         unsigned int ra_pages;          /* Maximum readahead window */
 923         unsigned int mmap_miss;         /* Cache miss stat for mmap accesses */
 924         loff_t prev_pos;                /* Cache last read() position */
 925 };
 926 
 927 /*
 928  * Check if @index falls in the readahead windows.
 929  */
 930 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
 931 {
 932         return (index >= ra->start &&
 933                 index <  ra->start + ra->size);
 934 }
 935 
 936 struct file {
 937         union {
 938                 struct llist_node       fu_llist;
 939                 struct rcu_head         fu_rcuhead;
 940         } f_u;
 941         struct path             f_path;
 942         struct inode            *f_inode;       /* cached value */
 943         const struct file_operations    *f_op;
 944 
 945         /*
 946          * Protects f_ep_links, f_flags.
 947          * Must not be taken from IRQ context.
 948          */
 949         spinlock_t              f_lock;
 950         enum rw_hint            f_write_hint;
 951         atomic_long_t           f_count;
 952         unsigned int            f_flags;
 953         fmode_t                 f_mode;
 954         struct mutex            f_pos_lock;
 955         loff_t                  f_pos;
 956         struct fown_struct      f_owner;
 957         const struct cred       *f_cred;
 958         struct file_ra_state    f_ra;
 959 
 960         u64                     f_version;
 961 #ifdef CONFIG_SECURITY
 962         void                    *f_security;
 963 #endif
 964         /* needed for tty driver, and maybe others */
 965         void                    *private_data;
 966 
 967 #ifdef CONFIG_EPOLL
 968         /* Used by fs/eventpoll.c to link all the hooks to this file */
 969         struct list_head        f_ep_links;
 970         struct list_head        f_tfile_llink;
 971 #endif /* #ifdef CONFIG_EPOLL */
 972         struct address_space    *f_mapping;
 973         errseq_t                f_wb_err;
 974 } __randomize_layout
 975   __attribute__((aligned(4)));  /* lest something weird decides that 2 is OK */
 976 
 977 struct file_handle {
 978         __u32 handle_bytes;
 979         int handle_type;
 980         /* file identifier */
 981         unsigned char f_handle[];
 982 };
 983 
 984 static inline struct file *get_file(struct file *f)
 985 {
 986         atomic_long_inc(&f->f_count);
 987         return f;
 988 }
 989 #define get_file_rcu_many(x, cnt)       \
 990         atomic_long_add_unless(&(x)->f_count, (cnt), 0)
 991 #define get_file_rcu(x) get_file_rcu_many((x), 1)
 992 #define file_count(x)   atomic_long_read(&(x)->f_count)
 993 
 994 #define MAX_NON_LFS     ((1UL<<31) - 1)
 995 
 996 /* Page cache limit. The filesystems should put that into their s_maxbytes 
 997    limits, otherwise bad things can happen in VM. */ 
 998 #if BITS_PER_LONG==32
 999 #define MAX_LFS_FILESIZE        ((loff_t)ULONG_MAX << PAGE_SHIFT)
1000 #elif BITS_PER_LONG==64
1001 #define MAX_LFS_FILESIZE        ((loff_t)LLONG_MAX)
1002 #endif
1003 
1004 #define FL_POSIX        1
1005 #define FL_FLOCK        2
1006 #define FL_DELEG        4       /* NFSv4 delegation */
1007 #define FL_ACCESS       8       /* not trying to lock, just looking */
1008 #define FL_EXISTS       16      /* when unlocking, test for existence */
1009 #define FL_LEASE        32      /* lease held on this file */
1010 #define FL_CLOSE        64      /* unlock on close */
1011 #define FL_SLEEP        128     /* A blocking lock */
1012 #define FL_DOWNGRADE_PENDING    256 /* Lease is being downgraded */
1013 #define FL_UNLOCK_PENDING       512 /* Lease is being broken */
1014 #define FL_OFDLCK       1024    /* lock is "owned" by struct file */
1015 #define FL_LAYOUT       2048    /* outstanding pNFS layout */
1016 
1017 #define FL_CLOSE_POSIX (FL_POSIX | FL_CLOSE)
1018 
1019 /*
1020  * Special return value from posix_lock_file() and vfs_lock_file() for
1021  * asynchronous locking.
1022  */
1023 #define FILE_LOCK_DEFERRED 1
1024 
1025 /* legacy typedef, should eventually be removed */
1026 typedef void *fl_owner_t;
1027 
1028 struct file_lock;
1029 
1030 struct file_lock_operations {
1031         void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
1032         void (*fl_release_private)(struct file_lock *);
1033 };
1034 
1035 struct lock_manager_operations {
1036         fl_owner_t (*lm_get_owner)(fl_owner_t);
1037         void (*lm_put_owner)(fl_owner_t);
1038         void (*lm_notify)(struct file_lock *);  /* unblock callback */
1039         int (*lm_grant)(struct file_lock *, int);
1040         bool (*lm_break)(struct file_lock *);
1041         int (*lm_change)(struct file_lock *, int, struct list_head *);
1042         void (*lm_setup)(struct file_lock *, void **);
1043 };
1044 
1045 struct lock_manager {
1046         struct list_head list;
1047         /*
1048          * NFSv4 and up also want opens blocked during the grace period;
1049          * NLM doesn't care:
1050          */
1051         bool block_opens;
1052 };
1053 
1054 struct net;
1055 void locks_start_grace(struct net *, struct lock_manager *);
1056 void locks_end_grace(struct lock_manager *);
1057 bool locks_in_grace(struct net *);
1058 bool opens_in_grace(struct net *);
1059 
1060 /* that will die - we need it for nfs_lock_info */
1061 #include <linux/nfs_fs_i.h>
1062 
1063 /*
1064  * struct file_lock represents a generic "file lock". It's used to represent
1065  * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
1066  * note that the same struct is used to represent both a request for a lock and
1067  * the lock itself, but the same object is never used for both.
1068  *
1069  * FIXME: should we create a separate "struct lock_request" to help distinguish
1070  * these two uses?
1071  *
1072  * The varous i_flctx lists are ordered by:
1073  *
1074  * 1) lock owner
1075  * 2) lock range start
1076  * 3) lock range end
1077  *
1078  * Obviously, the last two criteria only matter for POSIX locks.
1079  */
1080 struct file_lock {
1081         struct file_lock *fl_blocker;   /* The lock, that is blocking us */
1082         struct list_head fl_list;       /* link into file_lock_context */
1083         struct hlist_node fl_link;      /* node in global lists */
1084         struct list_head fl_blocked_requests;   /* list of requests with
1085                                                  * ->fl_blocker pointing here
1086                                                  */
1087         struct list_head fl_blocked_member;     /* node in
1088                                                  * ->fl_blocker->fl_blocked_requests
1089                                                  */
1090         fl_owner_t fl_owner;
1091         unsigned int fl_flags;
1092         unsigned char fl_type;
1093         unsigned int fl_pid;
1094         int fl_link_cpu;                /* what cpu's list is this on? */
1095         wait_queue_head_t fl_wait;
1096         struct file *fl_file;
1097         loff_t fl_start;
1098         loff_t fl_end;
1099 
1100         struct fasync_struct *  fl_fasync; /* for lease break notifications */
1101         /* for lease breaks: */
1102         unsigned long fl_break_time;
1103         unsigned long fl_downgrade_time;
1104 
1105         const struct file_lock_operations *fl_ops;      /* Callbacks for filesystems */
1106         const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
1107         union {
1108                 struct nfs_lock_info    nfs_fl;
1109                 struct nfs4_lock_info   nfs4_fl;
1110                 struct {
1111                         struct list_head link;  /* link in AFS vnode's pending_locks list */
1112                         int state;              /* state of grant or error if -ve */
1113                         unsigned int    debug_id;
1114                 } afs;
1115         } fl_u;
1116 } __randomize_layout;
1117 
1118 struct file_lock_context {
1119         spinlock_t              flc_lock;
1120         struct list_head        flc_flock;
1121         struct list_head        flc_posix;
1122         struct list_head        flc_lease;
1123 };
1124 
1125 /* The following constant reflects the upper bound of the file/locking space */
1126 #ifndef OFFSET_MAX
1127 #define INT_LIMIT(x)    (~((x)1 << (sizeof(x)*8 - 1)))
1128 #define OFFSET_MAX      INT_LIMIT(loff_t)
1129 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
1130 #endif
1131 
1132 extern void send_sigio(struct fown_struct *fown, int fd, int band);
1133 
1134 #define locks_inode(f) file_inode(f)
1135 
1136 #ifdef CONFIG_FILE_LOCKING
1137 extern int fcntl_getlk(struct file *, unsigned int, struct flock *);
1138 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
1139                         struct flock *);
1140 
1141 #if BITS_PER_LONG == 32
1142 extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 *);
1143 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
1144                         struct flock64 *);
1145 #endif
1146 
1147 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
1148 extern int fcntl_getlease(struct file *filp);
1149 
1150 /* fs/locks.c */
1151 void locks_free_lock_context(struct inode *inode);
1152 void locks_free_lock(struct file_lock *fl);
1153 extern void locks_init_lock(struct file_lock *);
1154 extern struct file_lock * locks_alloc_lock(void);
1155 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1156 extern void locks_copy_conflock(struct file_lock *, struct file_lock *);
1157 extern void locks_remove_posix(struct file *, fl_owner_t);
1158 extern void locks_remove_file(struct file *);
1159 extern void locks_release_private(struct file_lock *);
1160 extern void posix_test_lock(struct file *, struct file_lock *);
1161 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
1162 extern int locks_delete_block(struct file_lock *);
1163 extern int vfs_test_lock(struct file *, struct file_lock *);
1164 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
1165 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
1166 extern int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl);
1167 extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
1168 extern void lease_get_mtime(struct inode *, struct timespec64 *time);
1169 extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
1170 extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
1171 extern int lease_modify(struct file_lock *, int, struct list_head *);
1172 
1173 struct notifier_block;
1174 extern int lease_register_notifier(struct notifier_block *);
1175 extern void lease_unregister_notifier(struct notifier_block *);
1176 
1177 struct files_struct;
1178 extern void show_fd_locks(struct seq_file *f,
1179                          struct file *filp, struct files_struct *files);
1180 #else /* !CONFIG_FILE_LOCKING */
1181 static inline int fcntl_getlk(struct file *file, unsigned int cmd,
1182                               struct flock __user *user)
1183 {
1184         return -EINVAL;
1185 }
1186 
1187 static inline int fcntl_setlk(unsigned int fd, struct file *file,
1188                               unsigned int cmd, struct flock __user *user)
1189 {
1190         return -EACCES;
1191 }
1192 
1193 #if BITS_PER_LONG == 32
1194 static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
1195                                 struct flock64 __user *user)
1196 {
1197         return -EINVAL;
1198 }
1199 
1200 static inline int fcntl_setlk64(unsigned int fd, struct file *file,
1201                                 unsigned int cmd, struct flock64 __user *user)
1202 {
1203         return -EACCES;
1204 }
1205 #endif
1206 static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
1207 {
1208         return -EINVAL;
1209 }
1210 
1211 static inline int fcntl_getlease(struct file *filp)
1212 {
1213         return F_UNLCK;
1214 }
1215 
1216 static inline void
1217 locks_free_lock_context(struct inode *inode)
1218 {
1219 }
1220 
1221 static inline void locks_init_lock(struct file_lock *fl)
1222 {
1223         return;
1224 }
1225 
1226 static inline void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
1227 {
1228         return;
1229 }
1230 
1231 static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1232 {
1233         return;
1234 }
1235 
1236 static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
1237 {
1238         return;
1239 }
1240 
1241 static inline void locks_remove_file(struct file *filp)
1242 {
1243         return;
1244 }
1245 
1246 static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
1247 {
1248         return;
1249 }
1250 
1251 static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
1252                                   struct file_lock *conflock)
1253 {
1254         return -ENOLCK;
1255 }
1256 
1257 static inline int locks_delete_block(struct file_lock *waiter)
1258 {
1259         return -ENOENT;
1260 }
1261 
1262 static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
1263 {
1264         return 0;
1265 }
1266 
1267 static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
1268                                 struct file_lock *fl, struct file_lock *conf)
1269 {
1270         return -ENOLCK;
1271 }
1272 
1273 static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
1274 {
1275         return 0;
1276 }
1277 
1278 static inline int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl)
1279 {
1280         return -ENOLCK;
1281 }
1282 
1283 static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
1284 {
1285         return 0;
1286 }
1287 
1288 static inline void lease_get_mtime(struct inode *inode,
1289                                    struct timespec64 *time)
1290 {
1291         return;
1292 }
1293 
1294 static inline int generic_setlease(struct file *filp, long arg,
1295                                     struct file_lock **flp, void **priv)
1296 {
1297         return -EINVAL;
1298 }
1299 
1300 static inline int vfs_setlease(struct file *filp, long arg,
1301                                struct file_lock **lease, void **priv)
1302 {
1303         return -EINVAL;
1304 }
1305 
1306 static inline int lease_modify(struct file_lock *fl, int arg,
1307                                struct list_head *dispose)
1308 {
1309         return -EINVAL;
1310 }
1311 
1312 struct files_struct;
1313 static inline void show_fd_locks(struct seq_file *f,
1314                         struct file *filp, struct files_struct *files) {}
1315 #endif /* !CONFIG_FILE_LOCKING */
1316 
1317 static inline struct inode *file_inode(const struct file *f)
1318 {
1319         return f->f_inode;
1320 }
1321 
1322 static inline struct dentry *file_dentry(const struct file *file)
1323 {
1324         return d_real(file->f_path.dentry, file_inode(file));
1325 }
1326 
1327 static inline int locks_lock_file_wait(struct file *filp, struct file_lock *fl)
1328 {
1329         return locks_lock_inode_wait(locks_inode(filp), fl);
1330 }
1331 
1332 struct fasync_struct {
1333         rwlock_t                fa_lock;
1334         int                     magic;
1335         int                     fa_fd;
1336         struct fasync_struct    *fa_next; /* singly linked list */
1337         struct file             *fa_file;
1338         struct rcu_head         fa_rcu;
1339 };
1340 
1341 #define FASYNC_MAGIC 0x4601
1342 
1343 /* SMP safe fasync helpers: */
1344 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1345 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1346 extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1347 extern struct fasync_struct *fasync_alloc(void);
1348 extern void fasync_free(struct fasync_struct *);
1349 
1350 /* can be called from interrupts */
1351 extern void kill_fasync(struct fasync_struct **, int, int);
1352 
1353 extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1354 extern int f_setown(struct file *filp, unsigned long arg, int force);
1355 extern void f_delown(struct file *filp);
1356 extern pid_t f_getown(struct file *filp);
1357 extern int send_sigurg(struct fown_struct *fown);
1358 
1359 /*
1360  * sb->s_flags.  Note that these mirror the equivalent MS_* flags where
1361  * represented in both.
1362  */
1363 #define SB_RDONLY        1      /* Mount read-only */
1364 #define SB_NOSUID        2      /* Ignore suid and sgid bits */
1365 #define SB_NODEV         4      /* Disallow access to device special files */
1366 #define SB_NOEXEC        8      /* Disallow program execution */
1367 #define SB_SYNCHRONOUS  16      /* Writes are synced at once */
1368 #define SB_MANDLOCK     64      /* Allow mandatory locks on an FS */
1369 #define SB_DIRSYNC      128     /* Directory modifications are synchronous */
1370 #define SB_NOATIME      1024    /* Do not update access times. */
1371 #define SB_NODIRATIME   2048    /* Do not update directory access times */
1372 #define SB_SILENT       32768
1373 #define SB_POSIXACL     (1<<16) /* VFS does not apply the umask */
1374 #define SB_KERNMOUNT    (1<<22) /* this is a kern_mount call */
1375 #define SB_I_VERSION    (1<<23) /* Update inode I_version field */
1376 #define SB_LAZYTIME     (1<<25) /* Update the on-disk [acm]times lazily */
1377 
1378 /* These sb flags are internal to the kernel */
1379 #define SB_SUBMOUNT     (1<<26)
1380 #define SB_FORCE        (1<<27)
1381 #define SB_NOSEC        (1<<28)
1382 #define SB_BORN         (1<<29)
1383 #define SB_ACTIVE       (1<<30)
1384 #define SB_NOUSER       (1<<31)
1385 
1386 /*
1387  *      Umount options
1388  */
1389 
1390 #define MNT_FORCE       0x00000001      /* Attempt to forcibily umount */
1391 #define MNT_DETACH      0x00000002      /* Just detach from the tree */
1392 #define MNT_EXPIRE      0x00000004      /* Mark for expiry */
1393 #define UMOUNT_NOFOLLOW 0x00000008      /* Don't follow symlink on umount */
1394 #define UMOUNT_UNUSED   0x80000000      /* Flag guaranteed to be unused */
1395 
1396 /* sb->s_iflags */
1397 #define SB_I_CGROUPWB   0x00000001      /* cgroup-aware writeback enabled */
1398 #define SB_I_NOEXEC     0x00000002      /* Ignore executables on this fs */
1399 #define SB_I_NODEV      0x00000004      /* Ignore devices on this fs */
1400 #define SB_I_MULTIROOT  0x00000008      /* Multiple roots to the dentry tree */
1401 
1402 /* sb->s_iflags to limit user namespace mounts */
1403 #define SB_I_USERNS_VISIBLE             0x00000010 /* fstype already mounted */
1404 #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
1405 #define SB_I_UNTRUSTED_MOUNTER          0x00000040
1406 
1407 /* Possible states of 'frozen' field */
1408 enum {
1409         SB_UNFROZEN = 0,                /* FS is unfrozen */
1410         SB_FREEZE_WRITE = 1,            /* Writes, dir ops, ioctls frozen */
1411         SB_FREEZE_PAGEFAULT = 2,        /* Page faults stopped as well */
1412         SB_FREEZE_FS = 3,               /* For internal FS use (e.g. to stop
1413                                          * internal threads if needed) */
1414         SB_FREEZE_COMPLETE = 4,         /* ->freeze_fs finished successfully */
1415 };
1416 
1417 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1418 
1419 struct sb_writers {
1420         int                             frozen;         /* Is sb frozen? */
1421         wait_queue_head_t               wait_unfrozen;  /* for get_super_thawed() */
1422         struct percpu_rw_semaphore      rw_sem[SB_FREEZE_LEVELS];
1423 };
1424 
1425 struct super_block {
1426         struct list_head        s_list;         /* Keep this first */
1427         dev_t                   s_dev;          /* search index; _not_ kdev_t */
1428         unsigned char           s_blocksize_bits;
1429         unsigned long           s_blocksize;
1430         loff_t                  s_maxbytes;     /* Max file size */
1431         struct file_system_type *s_type;
1432         const struct super_operations   *s_op;
1433         const struct dquot_operations   *dq_op;
1434         const struct quotactl_ops       *s_qcop;
1435         const struct export_operations *s_export_op;
1436         unsigned long           s_flags;
1437         unsigned long           s_iflags;       /* internal SB_I_* flags */
1438         unsigned long           s_magic;
1439         struct dentry           *s_root;
1440         struct rw_semaphore     s_umount;
1441         int                     s_count;
1442         atomic_t                s_active;
1443 #ifdef CONFIG_SECURITY
1444         void                    *s_security;
1445 #endif
1446         const struct xattr_handler **s_xattr;
1447 #ifdef CONFIG_FS_ENCRYPTION
1448         const struct fscrypt_operations *s_cop;
1449         struct key              *s_master_keys; /* master crypto keys in use */
1450 #endif
1451 #ifdef CONFIG_FS_VERITY
1452         const struct fsverity_operations *s_vop;
1453 #endif
1454         struct hlist_bl_head    s_roots;        /* alternate root dentries for NFS */
1455         struct list_head        s_mounts;       /* list of mounts; _not_ for fs use */
1456         struct block_device     *s_bdev;
1457         struct backing_dev_info *s_bdi;
1458         struct mtd_info         *s_mtd;
1459         struct hlist_node       s_instances;
1460         unsigned int            s_quota_types;  /* Bitmask of supported quota types */
1461         struct quota_info       s_dquot;        /* Diskquota specific options */
1462 
1463         struct sb_writers       s_writers;
1464 
1465         /*
1466          * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
1467          * s_fsnotify_marks together for cache efficiency. They are frequently
1468          * accessed and rarely modified.
1469          */
1470         void                    *s_fs_info;     /* Filesystem private info */
1471 
1472         /* Granularity of c/m/atime in ns (cannot be worse than a second) */
1473         u32                     s_time_gran;
1474         /* Time limits for c/m/atime in seconds */
1475         time64_t                   s_time_min;
1476         time64_t                   s_time_max;
1477 #ifdef CONFIG_FSNOTIFY
1478         __u32                   s_fsnotify_mask;
1479         struct fsnotify_mark_connector __rcu    *s_fsnotify_marks;
1480 #endif
1481 
1482         char                    s_id[32];       /* Informational name */
1483         uuid_t                  s_uuid;         /* UUID */
1484 
1485         unsigned int            s_max_links;
1486         fmode_t                 s_mode;
1487 
1488         /*
1489          * The next field is for VFS *only*. No filesystems have any business
1490          * even looking at it. You had been warned.
1491          */
1492         struct mutex s_vfs_rename_mutex;        /* Kludge */
1493 
1494         /*
1495          * Filesystem subtype.  If non-empty the filesystem type field
1496          * in /proc/mounts will be "type.subtype"
1497          */
1498         const char *s_subtype;
1499 
1500         const struct dentry_operations *s_d_op; /* default d_op for dentries */
1501 
1502         /*
1503          * Saved pool identifier for cleancache (-1 means none)
1504          */
1505         int cleancache_poolid;
1506 
1507         struct shrinker s_shrink;       /* per-sb shrinker handle */
1508 
1509         /* Number of inodes with nlink == 0 but still referenced */
1510         atomic_long_t s_remove_count;
1511 
1512         /* Pending fsnotify inode refs */
1513         atomic_long_t s_fsnotify_inode_refs;
1514 
1515         /* Being remounted read-only */
1516         int s_readonly_remount;
1517 
1518         /* AIO completions deferred from interrupt context */
1519         struct workqueue_struct *s_dio_done_wq;
1520         struct hlist_head s_pins;
1521 
1522         /*
1523          * Owning user namespace and default context in which to
1524          * interpret filesystem uids, gids, quotas, device nodes,
1525          * xattrs and security labels.
1526          */
1527         struct user_namespace *s_user_ns;
1528 
1529         /*
1530          * The list_lru structure is essentially just a pointer to a table
1531          * of per-node lru lists, each of which has its own spinlock.
1532          * There is no need to put them into separate cachelines.
1533          */
1534         struct list_lru         s_dentry_lru;
1535         struct list_lru         s_inode_lru;
1536         struct rcu_head         rcu;
1537         struct work_struct      destroy_work;
1538 
1539         struct mutex            s_sync_lock;    /* sync serialisation lock */
1540 
1541         /*
1542          * Indicates how deep in a filesystem stack this SB is
1543          */
1544         int s_stack_depth;
1545 
1546         /* s_inode_list_lock protects s_inodes */
1547         spinlock_t              s_inode_list_lock ____cacheline_aligned_in_smp;
1548         struct list_head        s_inodes;       /* all inodes */
1549 
1550         spinlock_t              s_inode_wblist_lock;
1551         struct list_head        s_inodes_wb;    /* writeback inodes */
1552 } __randomize_layout;
1553 
1554 /* Helper functions so that in most cases filesystems will
1555  * not need to deal directly with kuid_t and kgid_t and can
1556  * instead deal with the raw numeric values that are stored
1557  * in the filesystem.
1558  */
1559 static inline uid_t i_uid_read(const struct inode *inode)
1560 {
1561         return from_kuid(inode->i_sb->s_user_ns, inode->i_uid);
1562 }
1563 
1564 static inline gid_t i_gid_read(const struct inode *inode)
1565 {
1566         return from_kgid(inode->i_sb->s_user_ns, inode->i_gid);
1567 }
1568 
1569 static inline void i_uid_write(struct inode *inode, uid_t uid)
1570 {
1571         inode->i_uid = make_kuid(inode->i_sb->s_user_ns, uid);
1572 }
1573 
1574 static inline void i_gid_write(struct inode *inode, gid_t gid)
1575 {
1576         inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
1577 }
1578 
1579 extern struct timespec64 timespec64_trunc(struct timespec64 t, unsigned gran);
1580 extern struct timespec64 current_time(struct inode *inode);
1581 
1582 /*
1583  * Snapshotting support.
1584  */
1585 
1586 void __sb_end_write(struct super_block *sb, int level);
1587 int __sb_start_write(struct super_block *sb, int level, bool wait);
1588 
1589 #define __sb_writers_acquired(sb, lev)  \
1590         percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1591 #define __sb_writers_release(sb, lev)   \
1592         percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1593 
1594 /**
1595  * sb_end_write - drop write access to a superblock
1596  * @sb: the super we wrote to
1597  *
1598  * Decrement number of writers to the filesystem. Wake up possible waiters
1599  * wanting to freeze the filesystem.
1600  */
1601 static inline void sb_end_write(struct super_block *sb)
1602 {
1603         __sb_end_write(sb, SB_FREEZE_WRITE);
1604 }
1605 
1606 /**
1607  * sb_end_pagefault - drop write access to a superblock from a page fault
1608  * @sb: the super we wrote to
1609  *
1610  * Decrement number of processes handling write page fault to the filesystem.
1611  * Wake up possible waiters wanting to freeze the filesystem.
1612  */
1613 static inline void sb_end_pagefault(struct super_block *sb)
1614 {
1615         __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1616 }
1617 
1618 /**
1619  * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1620  * @sb: the super we wrote to
1621  *
1622  * Decrement fs-internal number of writers to the filesystem.  Wake up possible
1623  * waiters wanting to freeze the filesystem.
1624  */
1625 static inline void sb_end_intwrite(struct super_block *sb)
1626 {
1627         __sb_end_write(sb, SB_FREEZE_FS);
1628 }
1629 
1630 /**
1631  * sb_start_write - get write access to a superblock
1632  * @sb: the super we write to
1633  *
1634  * When a process wants to write data or metadata to a file system (i.e. dirty
1635  * a page or an inode), it should embed the operation in a sb_start_write() -
1636  * sb_end_write() pair to get exclusion against file system freezing. This
1637  * function increments number of writers preventing freezing. If the file
1638  * system is already frozen, the function waits until the file system is
1639  * thawed.
1640  *
1641  * Since freeze protection behaves as a lock, users have to preserve
1642  * ordering of freeze protection and other filesystem locks. Generally,
1643  * freeze protection should be the outermost lock. In particular, we have:
1644  *
1645  * sb_start_write
1646  *   -> i_mutex                 (write path, truncate, directory ops, ...)
1647  *   -> s_umount                (freeze_super, thaw_super)
1648  */
1649 static inline void sb_start_write(struct super_block *sb)
1650 {
1651         __sb_start_write(sb, SB_FREEZE_WRITE, true);
1652 }
1653 
1654 static inline int sb_start_write_trylock(struct super_block *sb)
1655 {
1656         return __sb_start_write(sb, SB_FREEZE_WRITE, false);
1657 }
1658 
1659 /**
1660  * sb_start_pagefault - get write access to a superblock from a page fault
1661  * @sb: the super we write to
1662  *
1663  * When a process starts handling write page fault, it should embed the
1664  * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1665  * exclusion against file system freezing. This is needed since the page fault
1666  * is going to dirty a page. This function increments number of running page
1667  * faults preventing freezing. If the file system is already frozen, the
1668  * function waits until the file system is thawed.
1669  *
1670  * Since page fault freeze protection behaves as a lock, users have to preserve
1671  * ordering of freeze protection and other filesystem locks. It is advised to
1672  * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
1673  * handling code implies lock dependency:
1674  *
1675  * mmap_sem
1676  *   -> sb_start_pagefault
1677  */
1678 static inline void sb_start_pagefault(struct super_block *sb)
1679 {
1680         __sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
1681 }
1682 
1683 /*
1684  * sb_start_intwrite - get write access to a superblock for internal fs purposes
1685  * @sb: the super we write to
1686  *
1687  * This is the third level of protection against filesystem freezing. It is
1688  * free for use by a filesystem. The only requirement is that it must rank
1689  * below sb_start_pagefault.
1690  *
1691  * For example filesystem can call sb_start_intwrite() when starting a
1692  * transaction which somewhat eases handling of freezing for internal sources
1693  * of filesystem changes (internal fs threads, discarding preallocation on file
1694  * close, etc.).
1695  */
1696 static inline void sb_start_intwrite(struct super_block *sb)
1697 {
1698         __sb_start_write(sb, SB_FREEZE_FS, true);
1699 }
1700 
1701 static inline int sb_start_intwrite_trylock(struct super_block *sb)
1702 {
1703         return __sb_start_write(sb, SB_FREEZE_FS, false);
1704 }
1705 
1706 
1707 extern bool inode_owner_or_capable(const struct inode *inode);
1708 
1709 /*
1710  * VFS helper functions..
1711  */
1712 extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
1713 extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
1714 extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
1715 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
1716 extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
1717 extern int vfs_rmdir(struct inode *, struct dentry *);
1718 extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
1719 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
1720 extern int vfs_whiteout(struct inode *, struct dentry *);
1721 
1722 extern struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode,
1723                                   int open_flag);
1724 
1725 int vfs_mkobj(struct dentry *, umode_t,
1726                 int (*f)(struct dentry *, umode_t, void *),
1727                 void *);
1728 
1729 extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1730 
1731 #ifdef CONFIG_COMPAT
1732 extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
1733                                         unsigned long arg);
1734 #else
1735 #define compat_ptr_ioctl NULL
1736 #endif
1737 
1738 /*
1739  * VFS file helper functions.
1740  */
1741 extern void inode_init_owner(struct inode *inode, const struct inode *dir,
1742                         umode_t mode);
1743 extern bool may_open_dev(const struct path *path);
1744 /*
1745  * VFS FS_IOC_FIEMAP helper definitions.
1746  */
1747 struct fiemap_extent_info {
1748         unsigned int fi_flags;          /* Flags as passed from user */
1749         unsigned int fi_extents_mapped; /* Number of mapped extents */
1750         unsigned int fi_extents_max;    /* Size of fiemap_extent array */
1751         struct fiemap_extent __user *fi_extents_start; /* Start of
1752                                                         fiemap_extent array */
1753 };
1754 int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
1755                             u64 phys, u64 len, u32 flags);
1756 int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
1757 
1758 /*
1759  * This is the "filldir" function type, used by readdir() to let
1760  * the kernel specify what kind of dirent layout it wants to have.
1761  * This allows the kernel to read directories into kernel space or
1762  * to have different dirent layouts depending on the binary type.
1763  */
1764 struct dir_context;
1765 typedef int (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
1766                          unsigned);
1767 
1768 struct dir_context {
1769         filldir_t actor;
1770         loff_t pos;
1771 };
1772 
1773 struct block_device_operations;
1774 
1775 /* These macros are for out of kernel modules to test that
1776  * the kernel supports the unlocked_ioctl and compat_ioctl
1777  * fields in struct file_operations. */
1778 #define HAVE_COMPAT_IOCTL 1
1779 #define HAVE_UNLOCKED_IOCTL 1
1780 
1781 /*
1782  * These flags let !MMU mmap() govern direct device mapping vs immediate
1783  * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1784  *
1785  * NOMMU_MAP_COPY:      Copy can be mapped (MAP_PRIVATE)
1786  * NOMMU_MAP_DIRECT:    Can be mapped directly (MAP_SHARED)
1787  * NOMMU_MAP_READ:      Can be mapped for reading
1788  * NOMMU_MAP_WRITE:     Can be mapped for writing
1789  * NOMMU_MAP_EXEC:      Can be mapped for execution
1790  */
1791 #define NOMMU_MAP_COPY          0x00000001
1792 #define NOMMU_MAP_DIRECT        0x00000008
1793 #define NOMMU_MAP_READ          VM_MAYREAD
1794 #define NOMMU_MAP_WRITE         VM_MAYWRITE
1795 #define NOMMU_MAP_EXEC          VM_MAYEXEC
1796 
1797 #define NOMMU_VMFLAGS \
1798         (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1799 
1800 /*
1801  * These flags control the behavior of the remap_file_range function pointer.
1802  * If it is called with len == 0 that means "remap to end of source file".
1803  * See Documentation/filesystems/vfs.rst for more details about this call.
1804  *
1805  * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate)
1806  * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request
1807  */
1808 #define REMAP_FILE_DEDUP                (1 << 0)
1809 #define REMAP_FILE_CAN_SHORTEN          (1 << 1)
1810 
1811 /*
1812  * These flags signal that the caller is ok with altering various aspects of
1813  * the behavior of the remap operation.  The changes must be made by the
1814  * implementation; the vfs remap helper functions can take advantage of them.
1815  * Flags in this category exist to preserve the quirky behavior of the hoisted
1816  * btrfs clone/dedupe ioctls.
1817  */
1818 #define REMAP_FILE_ADVISORY             (REMAP_FILE_CAN_SHORTEN)
1819 
1820 struct iov_iter;
1821 
1822 struct file_operations {
1823         struct module *owner;
1824         loff_t (*llseek) (struct file *, loff_t, int);
1825         ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1826         ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1827         ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1828         ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1829         int (*iopoll)(struct kiocb *kiocb, bool spin);
1830         int (*iterate) (struct file *, struct dir_context *);
1831         int (*iterate_shared) (struct file *, struct dir_context *);
1832         __poll_t (*poll) (struct file *, struct poll_table_struct *);
1833         long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1834         long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1835         int (*mmap) (struct file *, struct vm_area_struct *);
1836         unsigned long mmap_supported_flags;
1837         int (*open) (struct inode *, struct file *);
1838         int (*flush) (struct file *, fl_owner_t id);
1839         int (*release) (struct inode *, struct file *);
1840         int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1841         int (*fasync) (int, struct file *, int);
1842         int (*lock) (struct file *, int, struct file_lock *);
1843         ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1844         unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1845         int (*check_flags)(int);
1846         int (*flock) (struct file *, int, struct file_lock *);
1847         ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1848         ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1849         int (*setlease)(struct file *, long, struct file_lock **, void **);
1850         long (*fallocate)(struct file *file, int mode, loff_t offset,
1851                           loff_t len);
1852         void (*show_fdinfo)(struct seq_file *m, struct file *f);
1853 #ifndef CONFIG_MMU
1854         unsigned (*mmap_capabilities)(struct file *);
1855 #endif
1856         ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
1857                         loff_t, size_t, unsigned int);
1858         loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
1859                                    struct file *file_out, loff_t pos_out,
1860                                    loff_t len, unsigned int remap_flags);
1861         int (*fadvise)(struct file *, loff_t, loff_t, int);
1862 } __randomize_layout;
1863 
1864 struct inode_operations {
1865         struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1866         const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
1867         int (*permission) (struct inode *, int);
1868         struct posix_acl * (*get_acl)(struct inode *, int);
1869 
1870         int (*readlink) (struct dentry *, char __user *,int);
1871 
1872         int (*create) (struct inode *,struct dentry *, umode_t, bool);
1873         int (*link) (struct dentry *,struct inode *,struct dentry *);
1874         int (*unlink) (struct inode *,struct dentry *);
1875         int (*symlink) (struct inode *,struct dentry *,const char *);
1876         int (*mkdir) (struct inode *,struct dentry *,umode_t);
1877         int (*rmdir) (struct inode *,struct dentry *);
1878         int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
1879         int (*rename) (struct inode *, struct dentry *,
1880                         struct inode *, struct dentry *, unsigned int);
1881         int (*setattr) (struct dentry *, struct iattr *);
1882         int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
1883         ssize_t (*listxattr) (struct dentry *, char *, size_t);
1884         int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1885                       u64 len);
1886         int (*update_time)(struct inode *, struct timespec64 *, int);
1887         int (*atomic_open)(struct inode *, struct dentry *,
1888                            struct file *, unsigned open_flag,
1889                            umode_t create_mode);
1890         int (*tmpfile) (struct inode *, struct dentry *, umode_t);
1891         int (*set_acl)(struct inode *, struct posix_acl *, int);
1892 } ____cacheline_aligned;
1893 
1894 static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
1895                                      struct iov_iter *iter)
1896 {
1897         return file->f_op->read_iter(kio, iter);
1898 }
1899 
1900 static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
1901                                       struct iov_iter *iter)
1902 {
1903         return file->f_op->write_iter(kio, iter);
1904 }
1905 
1906 static inline int call_mmap(struct file *file, struct vm_area_struct *vma)
1907 {
1908         return file->f_op->mmap(file, vma);
1909 }
1910 
1911 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1912                               unsigned long nr_segs, unsigned long fast_segs,
1913                               struct iovec *fast_pointer,
1914                               struct iovec **ret_pointer);
1915 
1916 extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
1917 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1918 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1919 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1920                 unsigned long, loff_t *, rwf_t);
1921 extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
1922                                    loff_t, size_t, unsigned int);
1923 extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in,
1924                                        struct file *file_out, loff_t pos_out,
1925                                        size_t len, unsigned int flags);
1926 extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
1927                                          struct file *file_out, loff_t pos_out,
1928                                          loff_t *count,
1929                                          unsigned int remap_flags);
1930 extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
1931                                   struct file *file_out, loff_t pos_out,
1932                                   loff_t len, unsigned int remap_flags);
1933 extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
1934                                    struct file *file_out, loff_t pos_out,
1935                                    loff_t len, unsigned int remap_flags);
1936 extern int vfs_dedupe_file_range(struct file *file,
1937                                  struct file_dedupe_range *same);
1938 extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
1939                                         struct file *dst_file, loff_t dst_pos,
1940                                         loff_t len, unsigned int remap_flags);
1941 
1942 
1943 struct super_operations {
1944         struct inode *(*alloc_inode)(struct super_block *sb);
1945         void (*destroy_inode)(struct inode *);
1946         void (*free_inode)(struct inode *);
1947 
1948         void (*dirty_inode) (struct inode *, int flags);
1949         int (*write_inode) (struct inode *, struct writeback_control *wbc);
1950         int (*drop_inode) (struct inode *);
1951         void (*evict_inode) (struct inode *);
1952         void (*put_super) (struct super_block *);
1953         int (*sync_fs)(struct super_block *sb, int wait);
1954         int (*freeze_super) (struct super_block *);
1955         int (*freeze_fs) (struct super_block *);
1956         int (*thaw_super) (struct super_block *);
1957         int (*unfreeze_fs) (struct super_block *);
1958         int (*statfs) (struct dentry *, struct kstatfs *);
1959         int (*remount_fs) (struct super_block *, int *, char *);
1960         void (*umount_begin) (struct super_block *);
1961 
1962         int (*show_options)(struct seq_file *, struct dentry *);
1963         int (*show_devname)(struct seq_file *, struct dentry *);
1964         int (*show_path)(struct seq_file *, struct dentry *);
1965         int (*show_stats)(struct seq_file *, struct dentry *);
1966 #ifdef CONFIG_QUOTA
1967         ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1968         ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1969         struct dquot **(*get_dquots)(struct inode *);
1970 #endif
1971         int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
1972         long (*nr_cached_objects)(struct super_block *,
1973                                   struct shrink_control *);
1974         long (*free_cached_objects)(struct super_block *,
1975                                     struct shrink_control *);
1976 };
1977 
1978 /*
1979  * Inode flags - they have no relation to superblock flags now
1980  */
1981 #define S_SYNC          1       /* Writes are synced at once */
1982 #define S_NOATIME       2       /* Do not update access times */
1983 #define S_APPEND        4       /* Append-only file */
1984 #define S_IMMUTABLE     8       /* Immutable file */
1985 #define S_DEAD          16      /* removed, but still open directory */
1986 #define S_NOQUOTA       32      /* Inode is not counted to quota */
1987 #define S_DIRSYNC       64      /* Directory modifications are synchronous */
1988 #define S_NOCMTIME      128     /* Do not update file c/mtime */
1989 #define S_SWAPFILE      256     /* Do not truncate: swapon got its bmaps */
1990 #define S_PRIVATE       512     /* Inode is fs-internal */
1991 #define S_IMA           1024    /* Inode has an associated IMA struct */
1992 #define S_AUTOMOUNT     2048    /* Automount/referral quasi-directory */
1993 #define S_NOSEC         4096    /* no suid or xattr security attributes */
1994 #ifdef CONFIG_FS_DAX
1995 #define S_DAX           8192    /* Direct Access, avoiding the page cache */
1996 #else
1997 #define S_DAX           0       /* Make all the DAX code disappear */
1998 #endif
1999 #define S_ENCRYPTED     16384   /* Encrypted file (using fs/crypto/) */
2000 #define S_CASEFOLD      32768   /* Casefolded file */
2001 #define S_VERITY        65536   /* Verity file (using fs/verity/) */
2002 
2003 /*
2004  * Note that nosuid etc flags are inode-specific: setting some file-system
2005  * flags just means all the inodes inherit those flags by default. It might be
2006  * possible to override it selectively if you really wanted to with some
2007  * ioctl() that is not currently implemented.
2008  *
2009  * Exception: SB_RDONLY is always applied to the entire file system.
2010  *
2011  * Unfortunately, it is possible to change a filesystems flags with it mounted
2012  * with files in use.  This means that all of the inodes will not have their
2013  * i_flags updated.  Hence, i_flags no longer inherit the superblock mount
2014  * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
2015  */
2016 #define __IS_FLG(inode, flg)    ((inode)->i_sb->s_flags & (flg))
2017 
2018 static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags & SB_RDONLY; }
2019 #define IS_RDONLY(inode)        sb_rdonly((inode)->i_sb)
2020 #define IS_SYNC(inode)          (__IS_FLG(inode, SB_SYNCHRONOUS) || \
2021                                         ((inode)->i_flags & S_SYNC))
2022 #define IS_DIRSYNC(inode)       (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
2023                                         ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
2024 #define IS_MANDLOCK(inode)      __IS_FLG(inode, SB_MANDLOCK)
2025 #define IS_NOATIME(inode)       __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
2026 #define IS_I_VERSION(inode)     __IS_FLG(inode, SB_I_VERSION)
2027 
2028 #define IS_NOQUOTA(inode)       ((inode)->i_flags & S_NOQUOTA)
2029 #define IS_APPEND(inode)        ((inode)->i_flags & S_APPEND)
2030 #define IS_IMMUTABLE(inode)     ((inode)->i_flags & S_IMMUTABLE)
2031 #define IS_POSIXACL(inode)      __IS_FLG(inode, SB_POSIXACL)
2032 
2033 #define IS_DEADDIR(inode)       ((inode)->i_flags & S_DEAD)
2034 #define IS_NOCMTIME(inode)      ((inode)->i_flags & S_NOCMTIME)
2035 #define IS_SWAPFILE(inode)      ((inode)->i_flags & S_SWAPFILE)
2036 #define IS_PRIVATE(inode)       ((inode)->i_flags & S_PRIVATE)
2037 #define IS_IMA(inode)           ((inode)->i_flags & S_IMA)
2038 #define IS_AUTOMOUNT(inode)     ((inode)->i_flags & S_AUTOMOUNT)
2039 #define IS_NOSEC(inode)         ((inode)->i_flags & S_NOSEC)
2040 #define IS_DAX(inode)           ((inode)->i_flags & S_DAX)
2041 #define IS_ENCRYPTED(inode)     ((inode)->i_flags & S_ENCRYPTED)
2042 #define IS_CASEFOLDED(inode)    ((inode)->i_flags & S_CASEFOLD)
2043 #define IS_VERITY(inode)        ((inode)->i_flags & S_VERITY)
2044 
2045 #define IS_WHITEOUT(inode)      (S_ISCHR(inode->i_mode) && \
2046                                  (inode)->i_rdev == WHITEOUT_DEV)
2047 
2048 static inline bool HAS_UNMAPPED_ID(struct inode *inode)
2049 {
2050         return !uid_valid(inode->i_uid) || !gid_valid(inode->i_gid);
2051 }
2052 
2053 static inline enum rw_hint file_write_hint(struct file *file)
2054 {
2055         if (file->f_write_hint != WRITE_LIFE_NOT_SET)
2056                 return file->f_write_hint;
2057 
2058         return file_inode(file)->i_write_hint;
2059 }
2060 
2061 static inline int iocb_flags(struct file *file);
2062 
2063 static inline u16 ki_hint_validate(enum rw_hint hint)
2064 {
2065         typeof(((struct kiocb *)0)->ki_hint) max_hint = -1;
2066 
2067         if (hint <= max_hint)
2068                 return hint;
2069         return 0;
2070 }
2071 
2072 static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
2073 {
2074         *kiocb = (struct kiocb) {
2075                 .ki_filp = filp,
2076                 .ki_flags = iocb_flags(filp),
2077                 .ki_hint = ki_hint_validate(file_write_hint(filp)),
2078                 .ki_ioprio = get_current_ioprio(),
2079         };
2080 }
2081 
2082 /*
2083  * Inode state bits.  Protected by inode->i_lock
2084  *
2085  * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
2086  * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
2087  *
2088  * Four bits define the lifetime of an inode.  Initially, inodes are I_NEW,
2089  * until that flag is cleared.  I_WILL_FREE, I_FREEING and I_CLEAR are set at
2090  * various stages of removing an inode.
2091  *
2092  * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
2093  *
2094  * I_DIRTY_SYNC         Inode is dirty, but doesn't have to be written on
2095  *                      fdatasync().  i_atime is the usual cause.
2096  * I_DIRTY_DATASYNC     Data-related inode changes pending. We keep track of
2097  *                      these changes separately from I_DIRTY_SYNC so that we
2098  *                      don't have to write inode on fdatasync() when only
2099  *                      mtime has changed in it.
2100  * I_DIRTY_PAGES        Inode has dirty pages.  Inode itself may be clean.
2101  * I_NEW                Serves as both a mutex and completion notification.
2102  *                      New inodes set I_NEW.  If two processes both create
2103  *                      the same inode, one of them will release its inode and
2104  *                      wait for I_NEW to be released before returning.
2105  *                      Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
2106  *                      also cause waiting on I_NEW, without I_NEW actually
2107  *                      being set.  find_inode() uses this to prevent returning
2108  *                      nearly-dead inodes.
2109  * I_WILL_FREE          Must be set when calling write_inode_now() if i_count
2110  *                      is zero.  I_FREEING must be set when I_WILL_FREE is
2111  *                      cleared.
2112  * I_FREEING            Set when inode is about to be freed but still has dirty
2113  *                      pages or buffers attached or the inode itself is still
2114  *                      dirty.
2115  * I_CLEAR              Added by clear_inode().  In this state the inode is
2116  *                      clean and can be destroyed.  Inode keeps I_FREEING.
2117  *
2118  *                      Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
2119  *                      prohibited for many purposes.  iget() must wait for
2120  *                      the inode to be completely released, then create it
2121  *                      anew.  Other functions will just ignore such inodes,
2122  *                      if appropriate.  I_NEW is used for waiting.
2123  *
2124  * I_SYNC               Writeback of inode is running. The bit is set during
2125  *                      data writeback, and cleared with a wakeup on the bit
2126  *                      address once it is done. The bit is also used to pin
2127  *                      the inode in memory for flusher thread.
2128  *
2129  * I_REFERENCED         Marks the inode as recently references on the LRU list.
2130  *
2131  * I_DIO_WAKEUP         Never set.  Only used as a key for wait_on_bit().
2132  *
2133  * I_WB_SWITCH          Cgroup bdi_writeback switching in progress.  Used to
2134  *                      synchronize competing switching instances and to tell
2135  *                      wb stat updates to grab the i_pages lock.  See
2136  *                      inode_switch_wbs_work_fn() for details.
2137  *
2138  * I_OVL_INUSE          Used by overlayfs to get exclusive ownership on upper
2139  *                      and work dirs among overlayfs mounts.
2140  *
2141  * I_CREATING           New object's inode in the middle of setting up.
2142  *
2143  * Q: What is the difference between I_WILL_FREE and I_FREEING?
2144  */
2145 #define I_DIRTY_SYNC            (1 << 0)
2146 #define I_DIRTY_DATASYNC        (1 << 1)
2147 #define I_DIRTY_PAGES           (1 << 2)
2148 #define __I_NEW                 3
2149 #define I_NEW                   (1 << __I_NEW)
2150 #define I_WILL_FREE             (1 << 4)
2151 #define I_FREEING               (1 << 5)
2152 #define I_CLEAR                 (1 << 6)
2153 #define __I_SYNC                7
2154 #define I_SYNC                  (1 << __I_SYNC)
2155 #define I_REFERENCED            (1 << 8)
2156 #define __I_DIO_WAKEUP          9
2157 #define I_DIO_WAKEUP            (1 << __I_DIO_WAKEUP)
2158 #define I_LINKABLE              (1 << 10)
2159 #define I_DIRTY_TIME            (1 << 11)
2160 #define __I_DIRTY_TIME_EXPIRED  12
2161 #define I_DIRTY_TIME_EXPIRED    (1 << __I_DIRTY_TIME_EXPIRED)
2162 #define I_WB_SWITCH             (1 << 13)
2163 #define I_OVL_INUSE             (1 << 14)
2164 #define I_CREATING              (1 << 15)
2165 
2166 #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
2167 #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
2168 #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
2169 
2170 extern void __mark_inode_dirty(struct inode *, int);
2171 static inline void mark_inode_dirty(struct inode *inode)
2172 {
2173         __mark_inode_dirty(inode, I_DIRTY);
2174 }
2175 
2176 static inline void mark_inode_dirty_sync(struct inode *inode)
2177 {
2178         __mark_inode_dirty(inode, I_DIRTY_SYNC);
2179 }
2180 
2181 extern void inc_nlink(struct inode *inode);
2182 extern void drop_nlink(struct inode *inode);
2183 extern void clear_nlink(struct inode *inode);
2184 extern void set_nlink(struct inode *inode, unsigned int nlink);
2185 
2186 static inline void inode_inc_link_count(struct inode *inode)
2187 {
2188         inc_nlink(inode);
2189         mark_inode_dirty(inode);
2190 }
2191 
2192 static inline void inode_dec_link_count(struct inode *inode)
2193 {
2194         drop_nlink(inode);
2195         mark_inode_dirty(inode);
2196 }
2197 
2198 enum file_time_flags {
2199         S_ATIME = 1,
2200         S_MTIME = 2,
2201         S_CTIME = 4,
2202         S_VERSION = 8,
2203 };
2204 
2205 extern bool atime_needs_update(const struct path *, struct inode *);
2206 extern void touch_atime(const struct path *);
2207 static inline void file_accessed(struct file *file)
2208 {
2209         if (!(file->f_flags & O_NOATIME))
2210                 touch_atime(&file->f_path);
2211 }
2212 
2213 extern int file_modified(struct file *file);
2214 
2215 int sync_inode(struct inode *inode, struct writeback_control *wbc);
2216 int sync_inode_metadata(struct inode *inode, int wait);
2217 
2218 struct file_system_type {
2219         const char *name;
2220         int fs_flags;
2221 #define FS_REQUIRES_DEV         1 
2222 #define FS_BINARY_MOUNTDATA     2
2223 #define FS_HAS_SUBTYPE          4
2224 #define FS_USERNS_MOUNT         8       /* Can be mounted by userns root */
2225 #define FS_DISALLOW_NOTIFY_PERM 16      /* Disable fanotify permission events */
2226 #define FS_RENAME_DOES_D_MOVE   32768   /* FS will handle d_move() during rename() internally. */
2227         int (*init_fs_context)(struct fs_context *);
2228         const struct fs_parameter_description *parameters;
2229         struct dentry *(*mount) (struct file_system_type *, int,
2230                        const char *, void *);
2231         void (*kill_sb) (struct super_block *);
2232         struct module *owner;
2233         struct file_system_type * next;
2234         struct hlist_head fs_supers;
2235 
2236         struct lock_class_key s_lock_key;
2237         struct lock_class_key s_umount_key;
2238         struct lock_class_key s_vfs_rename_key;
2239         struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
2240 
2241         struct lock_class_key i_lock_key;
2242         struct lock_class_key i_mutex_key;
2243         struct lock_class_key i_mutex_dir_key;
2244 };
2245 
2246 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2247 
2248 #ifdef CONFIG_BLOCK
2249 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
2250         int flags, const char *dev_name, void *data,
2251         int (*fill_super)(struct super_block *, void *, int));
2252 #else
2253 static inline struct dentry *mount_bdev(struct file_system_type *fs_type,
2254         int flags, const char *dev_name, void *data,
2255         int (*fill_super)(struct super_block *, void *, int))
2256 {
2257         return ERR_PTR(-ENODEV);
2258 }
2259 #endif
2260 extern struct dentry *mount_single(struct file_system_type *fs_type,
2261         int flags, void *data,
2262         int (*fill_super)(struct super_block *, void *, int));
2263 extern struct dentry *mount_nodev(struct file_system_type *fs_type,
2264         int flags, void *data,
2265         int (*fill_super)(struct super_block *, void *, int));
2266 extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
2267 void generic_shutdown_super(struct super_block *sb);
2268 #ifdef CONFIG_BLOCK
2269 void kill_block_super(struct super_block *sb);
2270 #else
2271 static inline void kill_block_super(struct super_block *sb)
2272 {
2273         BUG();
2274 }
2275 #endif
2276 void kill_anon_super(struct super_block *sb);
2277 void kill_litter_super(struct super_block *sb);
2278 void deactivate_super(struct super_block *sb);
2279 void deactivate_locked_super(struct super_block *sb);
2280 int set_anon_super(struct super_block *s, void *data);
2281 int set_anon_super_fc(struct super_block *s, struct fs_context *fc);
2282 int get_anon_bdev(dev_t *);
2283 void free_anon_bdev(dev_t);
2284 struct super_block *sget_fc(struct fs_context *fc,
2285                             int (*test)(struct super_block *, struct fs_context *),
2286                             int (*set)(struct super_block *, struct fs_context *));
2287 struct super_block *sget(struct file_system_type *type,
2288                         int (*test)(struct super_block *,void *),
2289                         int (*set)(struct super_block *,void *),
2290                         int flags, void *data);
2291 
2292 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2293 #define fops_get(fops) \
2294         (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2295 #define fops_put(fops) \
2296         do { if (fops) module_put((fops)->owner); } while(0)
2297 /*
2298  * This one is to be used *ONLY* from ->open() instances.
2299  * fops must be non-NULL, pinned down *and* module dependencies
2300  * should be sufficient to pin the caller down as well.
2301  */
2302 #define replace_fops(f, fops) \
2303         do {    \
2304                 struct file *__file = (f); \
2305                 fops_put(__file->f_op); \
2306                 BUG_ON(!(__file->f_op = (fops))); \
2307         } while(0)
2308 
2309 extern int register_filesystem(struct file_system_type *);
2310 extern int unregister_filesystem(struct file_system_type *);
2311 extern struct vfsmount *kern_mount(struct file_system_type *);
2312 extern void kern_unmount(struct vfsmount *mnt);
2313 extern int may_umount_tree(struct vfsmount *);
2314 extern int may_umount(struct vfsmount *);
2315 extern long do_mount(const char *, const char __user *,
2316                      const char *, unsigned long, void *);
2317 extern struct vfsmount *collect_mounts(const struct path *);
2318 extern void drop_collected_mounts(struct vfsmount *);
2319 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
2320                           struct vfsmount *);
2321 extern int vfs_statfs(const struct path *, struct kstatfs *);
2322 extern int user_statfs(const char __user *, struct kstatfs *);
2323 extern int fd_statfs(int, struct kstatfs *);
2324 extern int freeze_super(struct super_block *super);
2325 extern int thaw_super(struct super_block *super);
2326 extern bool our_mnt(struct vfsmount *mnt);
2327 extern __printf(2, 3)
2328 int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
2329 extern int super_setup_bdi(struct super_block *sb);
2330 
2331 extern int current_umask(void);
2332 
2333 extern void ihold(struct inode * inode);
2334 extern void iput(struct inode *);
2335 extern int generic_update_time(struct inode *, struct timespec64 *, int);
2336 
2337 /* /sys/fs */
2338 extern struct kobject *fs_kobj;
2339 
2340 #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2341 
2342 #ifdef CONFIG_MANDATORY_FILE_LOCKING
2343 extern int locks_mandatory_locked(struct file *);
2344 extern int locks_mandatory_area(struct inode *, struct file *, loff_t, loff_t, unsigned char);
2345 
2346 /*
2347  * Candidates for mandatory locking have the setgid bit set
2348  * but no group execute bit -  an otherwise meaningless combination.
2349  */
2350 
2351 static inline int __mandatory_lock(struct inode *ino)
2352 {
2353         return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
2354 }
2355 
2356 /*
2357  * ... and these candidates should be on SB_MANDLOCK mounted fs,
2358  * otherwise these will be advisory locks
2359  */
2360 
2361 static inline int mandatory_lock(struct inode *ino)
2362 {
2363         return IS_MANDLOCK(ino) && __mandatory_lock(ino);
2364 }
2365 
2366 static inline int locks_verify_locked(struct file *file)
2367 {
2368         if (mandatory_lock(locks_inode(file)))
2369                 return locks_mandatory_locked(file);
2370         return 0;
2371 }
2372 
2373 static inline int locks_verify_truncate(struct inode *inode,
2374                                     struct file *f,
2375                                     loff_t size)
2376 {
2377         if (!inode->i_flctx || !mandatory_lock(inode))
2378                 return 0;
2379 
2380         if (size < inode->i_size) {
2381                 return locks_mandatory_area(inode, f, size, inode->i_size - 1,
2382                                 F_WRLCK);
2383         } else {
2384                 return locks_mandatory_area(inode, f, inode->i_size, size - 1,
2385                                 F_WRLCK);
2386         }
2387 }
2388 
2389 #else /* !CONFIG_MANDATORY_FILE_LOCKING */
2390 
2391 static inline int locks_mandatory_locked(struct file *file)
2392 {
2393         return 0;
2394 }
2395 
2396 static inline int locks_mandatory_area(struct inode *inode, struct file *filp,
2397                                        loff_t start, loff_t end, unsigned char type)
2398 {
2399         return 0;
2400 }
2401 
2402 static inline int __mandatory_lock(struct inode *inode)
2403 {
2404         return 0;
2405 }
2406 
2407 static inline int mandatory_lock(struct inode *inode)
2408 {
2409         return 0;
2410 }
2411 
2412 static inline int locks_verify_locked(struct file *file)
2413 {
2414         return 0;
2415 }
2416 
2417 static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
2418                                         size_t size)
2419 {
2420         return 0;
2421 }
2422 
2423 #endif /* CONFIG_MANDATORY_FILE_LOCKING */
2424 
2425 
2426 #ifdef CONFIG_FILE_LOCKING
2427 static inline int break_lease(struct inode *inode, unsigned int mode)
2428 {
2429         /*
2430          * Since this check is lockless, we must ensure that any refcounts
2431          * taken are done before checking i_flctx->flc_lease. Otherwise, we
2432          * could end up racing with tasks trying to set a new lease on this
2433          * file.
2434          */
2435         smp_mb();
2436         if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2437                 return __break_lease(inode, mode, FL_LEASE);
2438         return 0;
2439 }
2440 
2441 static inline int break_deleg(struct inode *inode, unsigned int mode)
2442 {
2443         /*
2444          * Since this check is lockless, we must ensure that any refcounts
2445          * taken are done before checking i_flctx->flc_lease. Otherwise, we
2446          * could end up racing with tasks trying to set a new lease on this
2447          * file.
2448          */
2449         smp_mb();
2450         if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2451                 return __break_lease(inode, mode, FL_DELEG);
2452         return 0;
2453 }
2454 
2455 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2456 {
2457         int ret;
2458 
2459         ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
2460         if (ret == -EWOULDBLOCK && delegated_inode) {
2461                 *delegated_inode = inode;
2462                 ihold(inode);
2463         }
2464         return ret;
2465 }
2466 
2467 static inline int break_deleg_wait(struct inode **delegated_inode)
2468 {
2469         int ret;
2470 
2471         ret = break_deleg(*delegated_inode, O_WRONLY);
2472         iput(*delegated_inode);
2473         *delegated_inode = NULL;
2474         return ret;
2475 }
2476 
2477 static inline int break_layout(struct inode *inode, bool wait)
2478 {
2479         smp_mb();
2480         if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2481                 return __break_lease(inode,
2482                                 wait ? O_WRONLY : O_WRONLY | O_NONBLOCK,
2483                                 FL_LAYOUT);
2484         return 0;
2485 }
2486 
2487 #else /* !CONFIG_FILE_LOCKING */
2488 static inline int break_lease(struct inode *inode, unsigned int mode)
2489 {
2490         return 0;
2491 }
2492 
2493 static inline int break_deleg(struct inode *inode, unsigned int mode)
2494 {
2495         return 0;
2496 }
2497 
2498 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2499 {
2500         return 0;
2501 }
2502 
2503 static inline int break_deleg_wait(struct inode **delegated_inode)
2504 {
2505         BUG();
2506         return 0;
2507 }
2508 
2509 static inline int break_layout(struct inode *inode, bool wait)
2510 {
2511         return 0;
2512 }
2513 
2514 #endif /* CONFIG_FILE_LOCKING */
2515 
2516 /* fs/open.c */
2517 struct audit_names;
2518 struct filename {
2519         const char              *name;  /* pointer to actual string */
2520         const __user char       *uptr;  /* original userland pointer */
2521         int                     refcnt;
2522         struct audit_names      *aname;
2523         const char              iname[];
2524 };
2525 static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
2526 
2527 extern long vfs_truncate(const struct path *, loff_t);
2528 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
2529                        struct file *filp);
2530 extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2531                         loff_t len);
2532 extern long do_sys_open(int dfd, const char __user *filename, int flags,
2533                         umode_t mode);
2534 extern struct file *file_open_name(struct filename *, int, umode_t);
2535 extern struct file *filp_open(const char *, int, umode_t);
2536 extern struct file *file_open_root(struct dentry *, struct vfsmount *,
2537                                    const char *, int, umode_t);
2538 extern struct file * dentry_open(const struct path *, int, const struct cred *);
2539 extern struct file * open_with_fake_path(const struct path *, int,
2540                                          struct inode*, const struct cred *);
2541 static inline struct file *file_clone_open(struct file *file)
2542 {
2543         return dentry_open(&file->f_path, file->f_flags, file->f_cred);
2544 }
2545 extern int filp_close(struct file *, fl_owner_t id);
2546 
2547 extern struct filename *getname_flags(const char __user *, int, int *);
2548 extern struct filename *getname(const char __user *);
2549 extern struct filename *getname_kernel(const char *);
2550 extern void putname(struct filename *name);
2551 
2552 extern int finish_open(struct file *file, struct dentry *dentry,
2553                         int (*open)(struct inode *, struct file *));
2554 extern int finish_no_open(struct file *file, struct dentry *dentry);
2555 
2556 /* fs/ioctl.c */
2557 
2558 extern int ioctl_preallocate(struct file *filp, void __user *argp);
2559 
2560 /* fs/dcache.c */
2561 extern void __init vfs_caches_init_early(void);
2562 extern void __init vfs_caches_init(void);
2563 
2564 extern struct kmem_cache *names_cachep;
2565 
2566 #define __getname()             kmem_cache_alloc(names_cachep, GFP_KERNEL)
2567 #define __putname(name)         kmem_cache_free(names_cachep, (void *)(name))
2568 
2569 #ifdef CONFIG_BLOCK
2570 extern int register_blkdev(unsigned int, const char *);
2571 extern void unregister_blkdev(unsigned int, const char *);
2572 extern void bdev_unhash_inode(dev_t dev);
2573 extern struct block_device *bdget(dev_t);
2574 extern struct block_device *bdgrab(struct block_device *bdev);
2575 extern void bd_set_size(struct block_device *, loff_t size);
2576 extern void bd_forget(struct inode *inode);
2577 extern void bdput(struct block_device *);
2578 extern void invalidate_bdev(struct block_device *);
2579 extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
2580 extern int sync_blockdev(struct block_device *bdev);
2581 extern void kill_bdev(struct block_device *);
2582 extern struct super_block *freeze_bdev(struct block_device *);
2583 extern void emergency_thaw_all(void);
2584 extern void emergency_thaw_bdev(struct super_block *sb);
2585 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
2586 extern int fsync_bdev(struct block_device *);
2587 
2588 extern struct super_block *blockdev_superblock;
2589 
2590 static inline bool sb_is_blkdev_sb(struct super_block *sb)
2591 {
2592         return sb == blockdev_superblock;
2593 }
2594 #else
2595 static inline void bd_forget(struct inode *inode) {}
2596 static inline int sync_blockdev(struct block_device *bdev) { return 0; }
2597 static inline void kill_bdev(struct block_device *bdev) {}
2598 static inline void invalidate_bdev(struct block_device *bdev) {}
2599 
2600 static inline struct super_block *freeze_bdev(struct block_device *sb)
2601 {
2602         return NULL;
2603 }
2604 
2605 static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
2606 {
2607         return 0;
2608 }
2609 
2610 static inline int emergency_thaw_bdev(struct super_block *sb)
2611 {
2612         return 0;
2613 }
2614 
2615 static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
2616 {
2617 }
2618 
2619 static inline bool sb_is_blkdev_sb(struct super_block *sb)
2620 {
2621         return false;
2622 }
2623 #endif
2624 extern int sync_filesystem(struct super_block *);
2625 extern const struct file_operations def_blk_fops;
2626 extern const struct file_operations def_chr_fops;
2627 #ifdef CONFIG_BLOCK
2628 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
2629 extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
2630 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
2631 extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
2632 extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
2633                                                void *holder);
2634 extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
2635                                               void *holder);
2636 extern struct block_device *bd_start_claiming(struct block_device *bdev,
2637                                               void *holder);
2638 extern void bd_finish_claiming(struct block_device *bdev,
2639                                struct block_device *whole, void *holder);
2640 extern void bd_abort_claiming(struct block_device *bdev,
2641                               struct block_device *whole, void *holder);
2642 extern void blkdev_put(struct block_device *bdev, fmode_t mode);
2643 extern int __blkdev_reread_part(struct block_device *bdev);
2644 extern int blkdev_reread_part(struct block_device *bdev);
2645 
2646 #ifdef CONFIG_SYSFS
2647 extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
2648 extern void bd_unlink_disk_holder(struct block_device *bdev,
2649                                   struct gendisk *disk);
2650 #else
2651 static inline int bd_link_disk_holder(struct block_device *bdev,
2652                                       struct gendisk *disk)
2653 {
2654         return 0;
2655 }
2656 static inline void bd_unlink_disk_holder(struct block_device *bdev,
2657                                          struct gendisk *disk)
2658 {
2659 }
2660 #endif
2661 #endif
2662 
2663 /* fs/char_dev.c */
2664 #define CHRDEV_MAJOR_MAX 512
2665 /* Marks the bottom of the first segment of free char majors */
2666 #define CHRDEV_MAJOR_DYN_END 234
2667 /* Marks the top and bottom of the second segment of free char majors */
2668 #define CHRDEV_MAJOR_DYN_EXT_START 511
2669 #define CHRDEV_MAJOR_DYN_EXT_END 384
2670 
2671 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2672 extern int register_chrdev_region(dev_t, unsigned, const char *);
2673 extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2674                              unsigned int count, const char *name,
2675                              const struct file_operations *fops);
2676 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2677                                 unsigned int count, const char *name);
2678 extern void unregister_chrdev_region(dev_t, unsigned);
2679 extern void chrdev_show(struct seq_file *,off_t);
2680 
2681 static inline int register_chrdev(unsigned int major, const char *name,
2682                                   const struct file_operations *fops)
2683 {
2684         return __register_chrdev(major, 0, 256, name, fops);
2685 }
2686 
2687 static inline void unregister_chrdev(unsigned int major, const char *name)
2688 {
2689         __unregister_chrdev(major, 0, 256, name);
2690 }
2691 
2692 /* fs/block_dev.c */
2693 #define BDEVNAME_SIZE   32      /* Largest string for a blockdev identifier */
2694 #define BDEVT_SIZE      10      /* Largest string for MAJ:MIN for blkdev */
2695 
2696 #ifdef CONFIG_BLOCK
2697 #define BLKDEV_MAJOR_MAX        512
2698 extern const char *__bdevname(dev_t, char *buffer);
2699 extern const char *bdevname(struct block_device *bdev, char *buffer);
2700 extern struct block_device *lookup_bdev(const char *);
2701 extern void blkdev_show(struct seq_file *,off_t);
2702 
2703 #else
2704 #define BLKDEV_MAJOR_MAX        0
2705 #endif
2706 
2707 extern void init_special_inode(struct inode *, umode_t, dev_t);
2708 
2709 /* Invalid inode operations -- fs/bad_inode.c */
2710 extern void make_bad_inode(struct inode *);
2711 extern bool is_bad_inode(struct inode *);
2712 
2713 #ifdef CONFIG_BLOCK
2714 extern void check_disk_size_change(struct gendisk *disk,
2715                 struct block_device *bdev, bool verbose);
2716 extern int revalidate_disk(struct gendisk *);
2717 extern int check_disk_change(struct block_device *);
2718 extern int __invalidate_device(struct block_device *, bool);
2719 extern int invalidate_partition(struct gendisk *, int);
2720 #endif
2721 unsigned long invalidate_mapping_pages(struct address_space *mapping,
2722                                         pgoff_t start, pgoff_t end);
2723 
2724 static inline void invalidate_remote_inode(struct inode *inode)
2725 {
2726         if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2727             S_ISLNK(inode->i_mode))
2728                 invalidate_mapping_pages(inode->i_mapping, 0, -1);
2729 }
2730 extern int invalidate_inode_pages2(struct address_space *mapping);
2731 extern int invalidate_inode_pages2_range(struct address_space *mapping,
2732                                          pgoff_t start, pgoff_t end);
2733 extern int write_inode_now(struct inode *, int);
2734 extern int filemap_fdatawrite(struct address_space *);
2735 extern int filemap_flush(struct address_space *);
2736 extern int filemap_fdatawait_keep_errors(struct address_space *mapping);
2737 extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
2738                                    loff_t lend);
2739 extern int filemap_fdatawait_range_keep_errors(struct address_space *mapping,
2740                 loff_t start_byte, loff_t end_byte);
2741 
2742 static inline int filemap_fdatawait(struct address_space *mapping)
2743 {
2744         return filemap_fdatawait_range(mapping, 0, LLONG_MAX);
2745 }
2746 
2747 extern bool filemap_range_has_page(struct address_space *, loff_t lstart,
2748                                   loff_t lend);
2749 extern int filemap_write_and_wait(struct address_space *mapping);
2750 extern int filemap_write_and_wait_range(struct address_space *mapping,
2751                                         loff_t lstart, loff_t lend);
2752 extern int __filemap_fdatawrite_range(struct address_space *mapping,
2753                                 loff_t start, loff_t end, int sync_mode);
2754 extern int filemap_fdatawrite_range(struct address_space *mapping,
2755                                 loff_t start, loff_t end);
2756 extern int filemap_check_errors(struct address_space *mapping);
2757 extern void __filemap_set_wb_err(struct address_space *mapping, int err);
2758 
2759 extern int __must_check file_fdatawait_range(struct file *file, loff_t lstart,
2760                                                 loff_t lend);
2761 extern int __must_check file_check_and_advance_wb_err(struct file *file);
2762 extern int __must_check file_write_and_wait_range(struct file *file,
2763                                                 loff_t start, loff_t end);
2764 
2765 static inline int file_write_and_wait(struct file *file)
2766 {
2767         return file_write_and_wait_range(file, 0, LLONG_MAX);
2768 }
2769 
2770 /**
2771  * filemap_set_wb_err - set a writeback error on an address_space
2772  * @mapping: mapping in which to set writeback error
2773  * @err: error to be set in mapping
2774  *
2775  * When writeback fails in some way, we must record that error so that
2776  * userspace can be informed when fsync and the like are called.  We endeavor
2777  * to report errors on any file that was open at the time of the error.  Some
2778  * internal callers also need to know when writeback errors have occurred.
2779  *
2780  * When a writeback error occurs, most filesystems will want to call
2781  * filemap_set_wb_err to record the error in the mapping so that it will be
2782  * automatically reported whenever fsync is called on the file.
2783  */
2784 static inline void filemap_set_wb_err(struct address_space *mapping, int err)
2785 {
2786         /* Fastpath for common case of no error */
2787         if (unlikely(err))
2788                 __filemap_set_wb_err(mapping, err);
2789 }
2790 
2791 /**
2792  * filemap_check_wb_error - has an error occurred since the mark was sampled?
2793  * @mapping: mapping to check for writeback errors
2794  * @since: previously-sampled errseq_t
2795  *
2796  * Grab the errseq_t value from the mapping, and see if it has changed "since"
2797  * the given value was sampled.
2798  *
2799  * If it has then report the latest error set, otherwise return 0.
2800  */
2801 static inline int filemap_check_wb_err(struct address_space *mapping,
2802                                         errseq_t since)
2803 {
2804         return errseq_check(&mapping->wb_err, since);
2805 }
2806 
2807 /**
2808  * filemap_sample_wb_err - sample the current errseq_t to test for later errors
2809  * @mapping: mapping to be sampled
2810  *
2811  * Writeback errors are always reported relative to a particular sample point
2812  * in the past. This function provides those sample points.
2813  */
2814 static inline errseq_t filemap_sample_wb_err(struct address_space *mapping)
2815 {
2816         return errseq_sample(&mapping->wb_err);
2817 }
2818 
2819 static inline int filemap_nr_thps(struct address_space *mapping)
2820 {
2821 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
2822         return atomic_read(&mapping->nr_thps);
2823 #else
2824         return 0;
2825 #endif
2826 }
2827 
2828 static inline void filemap_nr_thps_inc(struct address_space *mapping)
2829 {
2830 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
2831         atomic_inc(&mapping->nr_thps);
2832 #else
2833         WARN_ON_ONCE(1);
2834 #endif
2835 }
2836 
2837 static inline void filemap_nr_thps_dec(struct address_space *mapping)
2838 {
2839 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
2840         atomic_dec(&mapping->nr_thps);
2841 #else
2842         WARN_ON_ONCE(1);
2843 #endif
2844 }
2845 
2846 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2847                            int datasync);
2848 extern int vfs_fsync(struct file *file, int datasync);
2849 
2850 extern int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
2851                                 unsigned int flags);
2852 
2853 /*
2854  * Sync the bytes written if this was a synchronous write.  Expect ki_pos
2855  * to already be updated for the write, and will return either the amount
2856  * of bytes passed in, or an error if syncing the file failed.
2857  */
2858 static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
2859 {
2860         if (iocb->ki_flags & IOCB_DSYNC) {
2861                 int ret = vfs_fsync_range(iocb->ki_filp,
2862                                 iocb->ki_pos - count, iocb->ki_pos - 1,
2863                                 (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
2864                 if (ret)
2865                         return ret;
2866         }
2867 
2868         return count;
2869 }
2870 
2871 extern void emergency_sync(void);
2872 extern void emergency_remount(void);
2873 #ifdef CONFIG_BLOCK
2874 extern sector_t bmap(struct inode *, sector_t);
2875 #endif
2876 extern int notify_change(struct dentry *, struct iattr *, struct inode **);
2877 extern int inode_permission(struct inode *, int);
2878 extern int generic_permission(struct inode *, int);
2879 extern int __check_sticky(struct inode *dir, struct inode *inode);
2880 
2881 static inline bool execute_ok(struct inode *inode)
2882 {
2883         return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2884 }
2885 
2886 static inline void file_start_write(struct file *file)
2887 {
2888         if (!S_ISREG(file_inode(file)->i_mode))
2889                 return;
2890         __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
2891 }
2892 
2893 static inline bool file_start_write_trylock(struct file *file)
2894 {
2895         if (!S_ISREG(file_inode(file)->i_mode))
2896                 return true;
2897         return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
2898 }
2899 
2900 static inline void file_end_write(struct file *file)
2901 {
2902         if (!S_ISREG(file_inode(file)->i_mode))
2903                 return;
2904         __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2905 }
2906 
2907 /*
2908  * get_write_access() gets write permission for a file.
2909  * put_write_access() releases this write permission.
2910  * This is used for regular files.
2911  * We cannot support write (and maybe mmap read-write shared) accesses and
2912  * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
2913  * can have the following values:
2914  * 0: no writers, no VM_DENYWRITE mappings
2915  * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
2916  * > 0: (i_writecount) users are writing to the file.
2917  *
2918  * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2919  * except for the cases where we don't hold i_writecount yet. Then we need to
2920  * use {get,deny}_write_access() - these functions check the sign and refuse
2921  * to do the change if sign is wrong.
2922  */
2923 static inline int get_write_access(struct inode *inode)
2924 {
2925         return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2926 }
2927 static inline int deny_write_access(struct file *file)
2928 {
2929         struct inode *inode = file_inode(file);
2930         return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2931 }
2932 static inline void put_write_access(struct inode * inode)
2933 {
2934         atomic_dec(&inode->i_writecount);
2935 }
2936 static inline void allow_write_access(struct file *file)
2937 {
2938         if (file)
2939                 atomic_inc(&file_inode(file)->i_writecount);
2940 }
2941 static inline bool inode_is_open_for_write(const struct inode *inode)
2942 {
2943         return atomic_read(&inode->i_writecount) > 0;
2944 }
2945 
2946 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
2947 static inline void i_readcount_dec(struct inode *inode)
2948 {
2949         BUG_ON(!atomic_read(&inode->i_readcount));
2950         atomic_dec(&inode->i_readcount);
2951 }
2952 static inline void i_readcount_inc(struct inode *inode)
2953 {
2954         atomic_inc(&inode->i_readcount);
2955 }
2956 #else
2957 static inline void i_readcount_dec(struct inode *inode)
2958 {
2959         return;
2960 }
2961 static inline void i_readcount_inc(struct inode *inode)
2962 {
2963         return;
2964 }
2965 #endif
2966 extern int do_pipe_flags(int *, int);
2967 
2968 #define __kernel_read_file_id(id) \
2969         id(UNKNOWN, unknown)            \
2970         id(FIRMWARE, firmware)          \
2971         id(FIRMWARE_PREALLOC_BUFFER, firmware)  \
2972         id(MODULE, kernel-module)               \
2973         id(KEXEC_IMAGE, kexec-image)            \
2974         id(KEXEC_INITRAMFS, kexec-initramfs)    \
2975         id(POLICY, security-policy)             \
2976         id(X509_CERTIFICATE, x509-certificate)  \
2977         id(MAX_ID, )
2978 
2979 #define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
2980 #define __fid_stringify(dummy, str) #str,
2981 
2982 enum kernel_read_file_id {
2983         __kernel_read_file_id(__fid_enumify)
2984 };
2985 
2986 static const char * const kernel_read_file_str[] = {
2987         __kernel_read_file_id(__fid_stringify)
2988 };
2989 
2990 static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id)
2991 {
2992         if ((unsigned)id >= READING_MAX_ID)
2993                 return kernel_read_file_str[READING_UNKNOWN];
2994 
2995         return kernel_read_file_str[id];
2996 }
2997 
2998 extern int kernel_read_file(struct file *, void **, loff_t *, loff_t,
2999                             enum kernel_read_file_id);
3000 extern int kernel_read_file_from_path(const char *, void **, loff_t *, loff_t,
3001                                       enum kernel_read_file_id);
3002 extern int kernel_read_file_from_fd(int, void **, loff_t *, loff_t,
3003                                     enum kernel_read_file_id);
3004 extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
3005 extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *);
3006 extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *);
3007 extern struct file * open_exec(const char *);
3008  
3009 /* fs/dcache.c -- generic fs support functions */
3010 extern bool is_subdir(struct dentry *, struct dentry *);
3011 extern bool path_is_under(const struct path *, const struct path *);
3012 
3013 extern char *file_path(struct file *, char *, int);
3014 
3015 #include <linux/err.h>
3016 
3017 /* needed for stackable file system support */
3018 extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
3019 
3020 extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
3021 
3022 extern int inode_init_always(struct super_block *, struct inode *);
3023 extern void inode_init_once(struct inode *);
3024 extern void address_space_init_once(struct address_space *mapping);
3025 extern struct inode * igrab(struct inode *);
3026 extern ino_t iunique(struct super_block *, ino_t);
3027 extern int inode_needs_sync(struct inode *inode);
3028 extern int generic_delete_inode(struct inode *inode);
3029 static inline int generic_drop_inode(struct inode *inode)
3030 {
3031         return !inode->i_nlink || inode_unhashed(inode);
3032 }
3033 
3034 extern struct inode *ilookup5_nowait(struct super_block *sb,
3035                 unsigned long hashval, int (*test)(struct inode *, void *),
3036                 void *data);
3037 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
3038                 int (*test)(struct inode *, void *), void *data);
3039 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
3040 
3041 extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
3042                 int (*test)(struct inode *, void *),
3043                 int (*set)(struct inode *, void *),
3044                 void *data);
3045 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
3046 extern struct inode * iget_locked(struct super_block *, unsigned long);
3047 extern struct inode *find_inode_nowait(struct super_block *,
3048                                        unsigned long,
3049                                        int (*match)(struct inode *,
3050                                                     unsigned long, void *),
3051                                        void *data);
3052 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
3053 extern int insert_inode_locked(struct inode *);
3054 #ifdef CONFIG_DEBUG_LOCK_ALLOC
3055 extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
3056 #else
3057 static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
3058 #endif
3059 extern void unlock_new_inode(struct inode *);
3060 extern void discard_new_inode(struct inode *);
3061 extern unsigned int get_next_ino(void);
3062 extern void evict_inodes(struct super_block *sb);
3063 
3064 extern void __iget(struct inode * inode);
3065 extern void iget_failed(struct inode *);
3066 extern void clear_inode(struct inode *);
3067 extern void __destroy_inode(struct inode *);
3068 extern struct inode *new_inode_pseudo(struct super_block *sb);
3069 extern struct inode *new_inode(struct super_block *sb);
3070 extern void free_inode_nonrcu(struct inode *inode);
3071 extern int should_remove_suid(struct dentry *);
3072 extern int file_remove_privs(struct file *);
3073 
3074 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
3075 static inline void insert_inode_hash(struct inode *inode)
3076 {
3077         __insert_inode_hash(inode, inode->i_ino);
3078 }
3079 
3080 extern void __remove_inode_hash(struct inode *);
3081 static inline void remove_inode_hash(struct inode *inode)
3082 {
3083         if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
3084                 __remove_inode_hash(inode);
3085 }
3086 
3087 extern void inode_sb_list_add(struct inode *inode);
3088 
3089 #ifdef CONFIG_BLOCK
3090 extern int bdev_read_only(struct block_device *);
3091 #endif
3092 extern int set_blocksize(struct block_device *, int);
3093 extern int sb_set_blocksize(struct super_block *, int);
3094 extern int sb_min_blocksize(struct super_block *, int);
3095 
3096 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
3097 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
3098 extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
3099 extern int generic_remap_checks(struct file *file_in, loff_t pos_in,
3100                                 struct file *file_out, loff_t pos_out,
3101                                 loff_t *count, unsigned int remap_flags);
3102 extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);
3103 extern int generic_copy_file_checks(struct file *file_in, loff_t pos_in,
3104                                     struct file *file_out, loff_t pos_out,
3105                                     size_t *count, unsigned int flags);
3106 extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
3107 extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
3108 extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
3109 extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
3110 extern ssize_t generic_perform_write(struct file *, struct iov_iter *, loff_t);
3111 
3112 ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
3113                 rwf_t flags);
3114 ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
3115                 rwf_t flags);
3116 
3117 /* fs/block_dev.c */
3118 extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);
3119 extern ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from);
3120 extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
3121                         int datasync);
3122 extern void block_sync_page(struct page *page);
3123 
3124 /* fs/splice.c */
3125 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
3126                 struct pipe_inode_info *, size_t, unsigned int);
3127 extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
3128                 struct file *, loff_t *, size_t, unsigned int);
3129 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
3130                 struct file *out, loff_t *, size_t len, unsigned int flags);
3131 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
3132                 loff_t *opos, size_t len, unsigned int flags);
3133 
3134 
3135 extern void
3136 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
3137 extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
3138 extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
3139 extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
3140 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
3141 extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
3142                 int whence, loff_t maxsize, loff_t eof);
3143 extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
3144                 int whence, loff_t size);
3145 extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
3146 extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
3147 extern int generic_file_open(struct inode * inode, struct file * filp);
3148 extern int nonseekable_open(struct inode * inode, struct file * filp);
3149 extern int stream_open(struct inode * inode, struct file * filp);
3150 
3151 #ifdef CONFIG_BLOCK
3152 typedef void (dio_submit_t)(struct bio *bio, struct inode *inode,
3153                             loff_t file_offset);
3154 
3155 enum {
3156         /* need locking between buffered and direct access */
3157         DIO_LOCKING     = 0x01,
3158 
3159         /* filesystem does not support filling holes */
3160         DIO_SKIP_HOLES  = 0x02,
3161 };
3162 
3163 void dio_end_io(struct bio *bio);
3164 void dio_warn_stale_pagecache(struct file *filp);
3165 
3166 ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
3167                              struct block_device *bdev, struct iov_iter *iter,
3168                              get_block_t get_block,
3169                              dio_iodone_t end_io, dio_submit_t submit_io,
3170                              int flags);
3171 
3172 static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
3173                                          struct inode *inode,
3174                                          struct iov_iter *iter,
3175                                          get_block_t get_block)
3176 {
3177         return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
3178                         get_block, NULL, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
3179 }
3180 #endif
3181 
3182 void inode_dio_wait(struct inode *inode);
3183 
3184 /*
3185  * inode_dio_begin - signal start of a direct I/O requests
3186  * @inode: inode the direct I/O happens on
3187  *
3188  * This is called once we've finished processing a direct I/O request,
3189  * and is used to wake up callers waiting for direct I/O to be quiesced.
3190  */
3191 static inline void inode_dio_begin(struct inode *inode)
3192 {
3193         atomic_inc(&inode->i_dio_count);
3194 }
3195 
3196 /*
3197  * inode_dio_end - signal finish of a direct I/O requests
3198  * @inode: inode the direct I/O happens on
3199  *
3200  * This is called once we've finished processing a direct I/O request,
3201  * and is used to wake up callers waiting for direct I/O to be quiesced.
3202  */
3203 static inline void inode_dio_end(struct inode *inode)
3204 {
3205         if (atomic_dec_and_test(&inode->i_dio_count))
3206                 wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
3207 }
3208 
3209 extern void inode_set_flags(struct inode *inode, unsigned int flags,
3210                             unsigned int mask);
3211 
3212 extern const struct file_operations generic_ro_fops;
3213 
3214 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
3215 
3216 extern int readlink_copy(char __user *, int, const char *);
3217 extern int page_readlink(struct dentry *, char __user *, int);
3218 extern const char *page_get_link(struct dentry *, struct inode *,
3219                                  struct delayed_call *);
3220 extern void page_put_link(void *);
3221 extern int __page_symlink(struct inode *inode, const char *symname, int len,
3222                 int nofs);
3223 extern int page_symlink(struct inode *inode, const char *symname, int len);
3224 extern const struct inode_operations page_symlink_inode_operations;
3225 extern void kfree_link(void *);
3226 extern void generic_fillattr(struct inode *, struct kstat *);
3227 extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
3228 extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
3229 void __inode_add_bytes(struct inode *inode, loff_t bytes);
3230 void inode_add_bytes(struct inode *inode, loff_t bytes);
3231 void __inode_sub_bytes(struct inode *inode, loff_t bytes);
3232 void inode_sub_bytes(struct inode *inode, loff_t bytes);
3233 static inline loff_t __inode_get_bytes(struct inode *inode)
3234 {
3235         return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
3236 }
3237 loff_t inode_get_bytes(struct inode *inode);
3238 void inode_set_bytes(struct inode *inode, loff_t bytes);
3239 const char *simple_get_link(struct dentry *, struct inode *,
3240                             struct delayed_call *);
3241 extern const struct inode_operations simple_symlink_inode_operations;
3242 
3243 extern int iterate_dir(struct file *, struct dir_context *);
3244 
3245 extern int vfs_statx(int, const char __user *, int, struct kstat *, u32);
3246 extern int vfs_statx_fd(unsigned int, struct kstat *, u32, unsigned int);
3247 
3248 static inline int vfs_stat(const char __user *filename, struct kstat *stat)
3249 {
3250         return vfs_statx(AT_FDCWD, filename, AT_NO_AUTOMOUNT,
3251                          stat, STATX_BASIC_STATS);
3252 }
3253 static inline int vfs_lstat(const char __user *name, struct kstat *stat)
3254 {
3255         return vfs_statx(AT_FDCWD, name, AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT,
3256                          stat, STATX_BASIC_STATS);
3257 }
3258 static inline int vfs_fstatat(int dfd, const char __user *filename,
3259                               struct kstat *stat, int flags)
3260 {
3261         return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
3262                          stat, STATX_BASIC_STATS);
3263 }
3264 static inline int vfs_fstat(int fd, struct kstat *stat)
3265 {
3266         return vfs_statx_fd(fd, stat, STATX_BASIC_STATS, 0);
3267 }
3268 
3269 
3270 extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
3271 extern int vfs_readlink(struct dentry *, char __user *, int);
3272 
3273 extern int __generic_block_fiemap(struct inode *inode,
3274                                   struct fiemap_extent_info *fieinfo,
3275                                   loff_t start, loff_t len,
3276                                   get_block_t *get_block);
3277 extern int generic_block_fiemap(struct inode *inode,
3278                                 struct fiemap_extent_info *fieinfo, u64 start,
3279                                 u64 len, get_block_t *get_block);
3280 
3281 extern struct file_system_type *get_filesystem(struct file_system_type *fs);
3282 extern void put_filesystem(struct file_system_type *fs);
3283 extern struct file_system_type *get_fs_type(const char *name);
3284 extern struct super_block *get_super(struct block_device *);
3285 extern struct super_block *get_super_thawed(struct block_device *);
3286 extern struct super_block *get_super_exclusive_thawed(struct block_device *bdev);
3287 extern struct super_block *get_active_super(struct block_device *bdev);
3288 extern void drop_super(struct super_block *sb);
3289 extern void drop_super_exclusive(struct super_block *sb);
3290 extern void iterate_supers(void (*)(struct super_block *, void *), void *);
3291 extern void iterate_supers_type(struct file_system_type *,
3292                                 void (*)(struct super_block *, void *), void *);
3293 
3294 extern int dcache_dir_open(struct inode *, struct file *);
3295 extern int dcache_dir_close(struct inode *, struct file *);
3296 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
3297 extern int dcache_readdir(struct file *, struct dir_context *);
3298 extern int simple_setattr(struct dentry *, struct iattr *);
3299 extern int simple_getattr(const struct path *, struct kstat *, u32, unsigned int);
3300 extern int simple_statfs(struct dentry *, struct kstatfs *);
3301 extern int simple_open(struct inode *inode, struct file *file);
3302 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
3303 extern int simple_unlink(struct inode *, struct dentry *);
3304 extern int simple_rmdir(struct inode *, struct dentry *);
3305 extern int simple_rename(struct inode *, struct dentry *,
3306                          struct inode *, struct dentry *, unsigned int);
3307 extern int noop_fsync(struct file *, loff_t, loff_t, int);
3308 extern int noop_set_page_dirty(struct page *page);
3309 extern void noop_invalidatepage(struct page *page, unsigned int offset,
3310                 unsigned int length);
3311 extern ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
3312 extern int simple_empty(struct dentry *);
3313 extern int simple_readpage(struct file *file, struct page *page);
3314 extern int simple_write_begin(struct file *file, struct address_space *mapping,
3315                         loff_t pos, unsigned len, unsigned flags,
3316                         struct page **pagep, void **fsdata);
3317 extern int simple_write_end(struct file *file, struct address_space *mapping,
3318                         loff_t pos, unsigned len, unsigned copied,
3319                         struct page *page, void *fsdata);
3320 extern int always_delete_dentry(const struct dentry *);
3321 extern struct inode *alloc_anon_inode(struct super_block *);
3322 extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
3323 extern const struct dentry_operations simple_dentry_operations;
3324 
3325 extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
3326 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
3327 extern const struct file_operations simple_dir_operations;
3328 extern const struct inode_operations simple_dir_inode_operations;
3329 extern void make_empty_dir_inode(struct inode *inode);
3330 extern bool is_empty_dir_inode(struct inode *inode);
3331 struct tree_descr { const char *name; const struct file_operations *ops; int mode; };
3332 struct dentry *d_alloc_name(struct dentry *, const char *);
3333 extern int simple_fill_super(struct super_block *, unsigned long,
3334                              const struct tree_descr *);
3335 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
3336 extern void simple_release_fs(struct vfsmount **mount, int *count);
3337 
3338 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
3339                         loff_t *ppos, const void *from, size_t available);
3340 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
3341                 const void __user *from, size_t count);
3342 
3343 extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
3344 extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
3345 
3346 extern int generic_check_addressable(unsigned, u64);
3347 
3348 #ifdef CONFIG_MIGRATION
3349 extern int buffer_migrate_page(struct address_space *,
3350                                 struct page *, struct page *,
3351                                 enum migrate_mode);
3352 extern int buffer_migrate_page_norefs(struct address_space *,
3353                                 struct page *, struct page *,
3354                                 enum migrate_mode);
3355 #else
3356 #define buffer_migrate_page NULL
3357 #define buffer_migrate_page_norefs NULL
3358 #endif
3359 
3360 extern int setattr_prepare(struct dentry *, struct iattr *);
3361 extern int inode_newsize_ok(const struct inode *, loff_t offset);
3362 extern void setattr_copy(struct inode *inode, const struct iattr *attr);
3363 
3364 extern int file_update_time(struct file *file);
3365 
3366 static inline bool io_is_direct(struct file *filp)
3367 {
3368         return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);
3369 }
3370 
3371 static inline bool vma_is_dax(struct vm_area_struct *vma)
3372 {
3373         return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
3374 }
3375 
3376 static inline bool vma_is_fsdax(struct vm_area_struct *vma)
3377 {
3378         struct inode *inode;
3379 
3380         if (!vma->vm_file)
3381                 return false;
3382         if (!vma_is_dax(vma))
3383                 return false;
3384         inode = file_inode(vma->vm_file);
3385         if (S_ISCHR(inode->i_mode))
3386                 return false; /* device-dax */
3387         return true;
3388 }
3389 
3390 static inline int iocb_flags(struct file *file)
3391 {
3392         int res = 0;
3393         if (file->f_flags & O_APPEND)
3394                 res |= IOCB_APPEND;
3395         if (io_is_direct(file))
3396                 res |= IOCB_DIRECT;
3397         if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
3398                 res |= IOCB_DSYNC;
3399         if (file->f_flags & __O_SYNC)
3400                 res |= IOCB_SYNC;
3401         return res;
3402 }
3403 
3404 static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
3405 {
3406         if (unlikely(flags & ~RWF_SUPPORTED))
3407                 return -EOPNOTSUPP;
3408 
3409         if (flags & RWF_NOWAIT) {
3410                 if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
3411                         return -EOPNOTSUPP;
3412                 ki->ki_flags |= IOCB_NOWAIT;
3413         }
3414         if (flags & RWF_HIPRI)
3415                 ki->ki_flags |= IOCB_HIPRI;
3416         if (flags & RWF_DSYNC)
3417                 ki->ki_flags |= IOCB_DSYNC;
3418         if (flags & RWF_SYNC)
3419                 ki->ki_flags |= (IOCB_DSYNC | IOCB_SYNC);
3420         if (flags & RWF_APPEND)
3421                 ki->ki_flags |= IOCB_APPEND;
3422         return 0;
3423 }
3424 
3425 static inline ino_t parent_ino(struct dentry *dentry)
3426 {
3427         ino_t res;
3428 
3429         /*
3430          * Don't strictly need d_lock here? If the parent ino could change
3431          * then surely we'd have a deeper race in the caller?
3432          */
3433         spin_lock(&dentry->d_lock);
3434         res = dentry->d_parent->d_inode->i_ino;
3435         spin_unlock(&dentry->d_lock);
3436         return res;
3437 }
3438 
3439 /* Transaction based IO helpers */
3440 
3441 /*
3442  * An argresp is stored in an allocated page and holds the
3443  * size of the argument or response, along with its content
3444  */
3445 struct simple_transaction_argresp {
3446         ssize_t size;
3447         char data[0];
3448 };
3449 
3450 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3451 
3452 char *simple_transaction_get(struct file *file, const char __user *buf,
3453                                 size_t size);
3454 ssize_t simple_transaction_read(struct file *file, char __user *buf,
3455                                 size_t size, loff_t *pos);
3456 int simple_transaction_release(struct inode *inode, struct file *file);
3457 
3458 void simple_transaction_set(struct file *file, size_t n);
3459 
3460 /*
3461  * simple attribute files
3462  *
3463  * These attributes behave similar to those in sysfs:
3464  *
3465  * Writing to an attribute immediately sets a value, an open file can be
3466  * written to multiple times.
3467  *
3468  * Reading from an attribute creates a buffer from the value that might get
3469  * read with multiple read calls. When the attribute has been read
3470  * completely, no further read calls are possible until the file is opened
3471  * again.
3472  *
3473  * All attributes contain a text representation of a numeric value
3474  * that are accessed with the get() and set() functions.
3475  */
3476 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt)            \
3477 static int __fops ## _open(struct inode *inode, struct file *file)      \
3478 {                                                                       \
3479         __simple_attr_check_format(__fmt, 0ull);                        \
3480         return simple_attr_open(inode, file, __get, __set, __fmt);      \
3481 }                                                                       \
3482 static const struct file_operations __fops = {                          \
3483         .owner   = THIS_MODULE,                                         \
3484         .open    = __fops ## _open,                                     \
3485         .release = simple_attr_release,                                 \
3486         .read    = simple_attr_read,                                    \
3487         .write   = simple_attr_write,                                   \
3488         .llseek  = generic_file_llseek,                                 \
3489 }
3490 
3491 static inline __printf(1, 2)
3492 void __simple_attr_check_format(const char *fmt, ...)
3493 {
3494         /* don't do anything, just let the compiler check the arguments; */
3495 }
3496 
3497 int simple_attr_open(struct inode *inode, struct file *file,
3498                      int (*get)(void *, u64 *), int (*set)(void *, u64),
3499                      const char *fmt);
3500 int simple_attr_release(struct inode *inode, struct file *file);
3501 ssize_t simple_attr_read(struct file *file, char __user *buf,
3502                          size_t len, loff_t *ppos);
3503 ssize_t simple_attr_write(struct file *file, const char __user *buf,
3504                           size_t len, loff_t *ppos);
3505 
3506 struct ctl_table;
3507 int proc_nr_files(struct ctl_table *table, int write,
3508                   void __user *buffer, size_t *lenp, loff_t *ppos);
3509 int proc_nr_dentry(struct ctl_table *table, int write,
3510                   void __user *buffer, size_t *lenp, loff_t *ppos);
3511 int proc_nr_inodes(struct ctl_table *table, int write,
3512                    void __user *buffer, size_t *lenp, loff_t *ppos);
3513 int __init get_filesystem_list(char *buf);
3514 
3515 #define __FMODE_EXEC            ((__force int) FMODE_EXEC)
3516 #define __FMODE_NONOTIFY        ((__force int) FMODE_NONOTIFY)
3517 
3518 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3519 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3520                                             (flag & __FMODE_NONOTIFY)))
3521 
3522 static inline bool is_sxid(umode_t mode)
3523 {
3524         return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
3525 }
3526 
3527 static inline int check_sticky(struct inode *dir, struct inode *inode)
3528 {
3529         if (!(dir->i_mode & S_ISVTX))
3530                 return 0;
3531 
3532         return __check_sticky(dir, inode);
3533 }
3534 
3535 static inline void inode_has_no_xattr(struct inode *inode)
3536 {
3537         if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & SB_NOSEC))
3538                 inode->i_flags |= S_NOSEC;
3539 }
3540 
3541 static inline bool is_root_inode(struct inode *inode)
3542 {
3543         return inode == inode->i_sb->s_root->d_inode;
3544 }
3545 
3546 static inline bool dir_emit(struct dir_context *ctx,
3547                             const char *name, int namelen,
3548                             u64 ino, unsigned type)
3549 {
3550         return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
3551 }
3552 static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
3553 {
3554         return ctx->actor(ctx, ".", 1, ctx->pos,
3555                           file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
3556 }
3557 static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
3558 {
3559         return ctx->actor(ctx, "..", 2, ctx->pos,
3560                           parent_ino(file->f_path.dentry), DT_DIR) == 0;
3561 }
3562 static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
3563 {
3564         if (ctx->pos == 0) {
3565                 if (!dir_emit_dot(file, ctx))
3566                         return false;
3567                 ctx->pos = 1;
3568         }
3569         if (ctx->pos == 1) {
3570                 if (!dir_emit_dotdot(file, ctx))
3571                         return false;
3572                 ctx->pos = 2;
3573         }
3574         return true;
3575 }
3576 static inline bool dir_relax(struct inode *inode)
3577 {
3578         inode_unlock(inode);
3579         inode_lock(inode);
3580         return !IS_DEADDIR(inode);
3581 }
3582 
3583 static inline bool dir_relax_shared(struct inode *inode)
3584 {
3585         inode_unlock_shared(inode);
3586         inode_lock_shared(inode);
3587         return !IS_DEADDIR(inode);
3588 }
3589 
3590 extern bool path_noexec(const struct path *path);
3591 extern void inode_nohighmem(struct inode *inode);
3592 
3593 /* mm/fadvise.c */
3594 extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len,
3595                        int advice);
3596 extern int generic_fadvise(struct file *file, loff_t offset, loff_t len,
3597                            int advice);
3598 
3599 #if defined(CONFIG_IO_URING)
3600 extern struct sock *io_uring_get_socket(struct file *file);
3601 #else
3602 static inline struct sock *io_uring_get_socket(struct file *file)
3603 {
3604         return NULL;
3605 }
3606 #endif
3607 
3608 int vfs_ioc_setflags_prepare(struct inode *inode, unsigned int oldflags,
3609                              unsigned int flags);
3610 
3611 int vfs_ioc_fssetxattr_check(struct inode *inode, const struct fsxattr *old_fa,
3612                              struct fsxattr *fa);
3613 
3614 static inline void simple_fill_fsxattr(struct fsxattr *fa, __u32 xflags)
3615 {
3616         memset(fa, 0, sizeof(*fa));
3617         fa->fsx_xflags = xflags;
3618 }
3619 
3620 /*
3621  * Flush file data before changing attributes.  Caller must hold any locks
3622  * required to prevent further writes to this file until we're done setting
3623  * flags.
3624  */
3625 static inline int inode_drain_writes(struct inode *inode)
3626 {
3627         inode_dio_wait(inode);
3628         return filemap_write_and_wait(inode->i_mapping);
3629 }
3630 
3631 #endif /* _LINUX_FS_H */