Line data Source code
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/rculist_bl.h>
28 : #include <linux/atomic.h>
29 : #include <linux/shrinker.h>
30 : #include <linux/migrate_mode.h>
31 : #include <linux/uidgid.h>
32 : #include <linux/lockdep.h>
33 : #include <linux/percpu-rwsem.h>
34 : #include <linux/workqueue.h>
35 : #include <linux/delayed_call.h>
36 : #include <linux/uuid.h>
37 : #include <linux/errseq.h>
38 : #include <linux/ioprio.h>
39 : #include <linux/fs_types.h>
40 : #include <linux/build_bug.h>
41 : #include <linux/stddef.h>
42 : #include <linux/mount.h>
43 : #include <linux/cred.h>
44 : #include <linux/mnt_idmapping.h>
45 : #include <linux/slab.h>
46 :
47 : #include <asm/byteorder.h>
48 : #include <uapi/linux/fs.h>
49 :
50 : struct backing_dev_info;
51 : struct bdi_writeback;
52 : struct bio;
53 : struct io_comp_batch;
54 : struct export_operations;
55 : struct fiemap_extent_info;
56 : struct hd_geometry;
57 : struct iovec;
58 : struct kiocb;
59 : struct kobject;
60 : struct pipe_inode_info;
61 : struct poll_table_struct;
62 : struct kstatfs;
63 : struct vm_area_struct;
64 : struct vfsmount;
65 : struct cred;
66 : struct swap_info_struct;
67 : struct seq_file;
68 : struct workqueue_struct;
69 : struct iov_iter;
70 : struct fscrypt_info;
71 : struct fscrypt_operations;
72 : struct fsverity_info;
73 : struct fsverity_operations;
74 : struct fs_context;
75 : struct fs_parameter_spec;
76 : struct fileattr;
77 : struct iomap_ops;
78 :
79 : extern void __init inode_init(void);
80 : extern void __init inode_init_early(void);
81 : extern void __init files_init(void);
82 : extern void __init files_maxfiles_init(void);
83 :
84 : extern unsigned long get_max_files(void);
85 : extern unsigned int sysctl_nr_open;
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/mem): 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 supports DIRECT IO */
167 : #define FMODE_CAN_ODIRECT ((__force fmode_t)0x400000)
168 :
169 : #define FMODE_NOREUSE ((__force fmode_t)0x800000)
170 :
171 : /* File supports non-exclusive O_DIRECT writes from multiple threads */
172 : #define FMODE_DIO_PARALLEL_WRITE ((__force fmode_t)0x1000000)
173 :
174 : /* File was opened by fanotify and shouldn't generate fanotify events */
175 : #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
176 :
177 : /* File is capable of returning -EAGAIN if I/O will block */
178 : #define FMODE_NOWAIT ((__force fmode_t)0x8000000)
179 :
180 : /* File represents mount that needs unmounting */
181 : #define FMODE_NEED_UNMOUNT ((__force fmode_t)0x10000000)
182 :
183 : /* File does not contribute to nr_files count */
184 : #define FMODE_NOACCOUNT ((__force fmode_t)0x20000000)
185 :
186 : /* File supports async buffered reads */
187 : #define FMODE_BUF_RASYNC ((__force fmode_t)0x40000000)
188 :
189 : /* File supports async nowait buffered writes */
190 : #define FMODE_BUF_WASYNC ((__force fmode_t)0x80000000)
191 :
192 : /*
193 : * Attribute flags. These should be or-ed together to figure out what
194 : * has been changed!
195 : */
196 : #define ATTR_MODE (1 << 0)
197 : #define ATTR_UID (1 << 1)
198 : #define ATTR_GID (1 << 2)
199 : #define ATTR_SIZE (1 << 3)
200 : #define ATTR_ATIME (1 << 4)
201 : #define ATTR_MTIME (1 << 5)
202 : #define ATTR_CTIME (1 << 6)
203 : #define ATTR_ATIME_SET (1 << 7)
204 : #define ATTR_MTIME_SET (1 << 8)
205 : #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
206 : #define ATTR_KILL_SUID (1 << 11)
207 : #define ATTR_KILL_SGID (1 << 12)
208 : #define ATTR_FILE (1 << 13)
209 : #define ATTR_KILL_PRIV (1 << 14)
210 : #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
211 : #define ATTR_TIMES_SET (1 << 16)
212 : #define ATTR_TOUCH (1 << 17)
213 :
214 : /*
215 : * Whiteout is represented by a char device. The following constants define the
216 : * mode and device number to use.
217 : */
218 : #define WHITEOUT_MODE 0
219 : #define WHITEOUT_DEV 0
220 :
221 : /*
222 : * This is the Inode Attributes structure, used for notify_change(). It
223 : * uses the above definitions as flags, to know which values have changed.
224 : * Also, in this manner, a Filesystem can look at only the values it cares
225 : * about. Basically, these are the attributes that the VFS layer can
226 : * request to change from the FS layer.
227 : *
228 : * Derek Atkins <warlord@MIT.EDU> 94-10-20
229 : */
230 : struct iattr {
231 : unsigned int ia_valid;
232 : umode_t ia_mode;
233 : /*
234 : * The two anonymous unions wrap structures with the same member.
235 : *
236 : * Filesystems raising FS_ALLOW_IDMAP need to use ia_vfs{g,u}id which
237 : * are a dedicated type requiring the filesystem to use the dedicated
238 : * helpers. Other filesystem can continue to use ia_{g,u}id until they
239 : * have been ported.
240 : *
241 : * They always contain the same value. In other words FS_ALLOW_IDMAP
242 : * pass down the same value on idmapped mounts as they would on regular
243 : * mounts.
244 : */
245 : union {
246 : kuid_t ia_uid;
247 : vfsuid_t ia_vfsuid;
248 : };
249 : union {
250 : kgid_t ia_gid;
251 : vfsgid_t ia_vfsgid;
252 : };
253 : loff_t ia_size;
254 : struct timespec64 ia_atime;
255 : struct timespec64 ia_mtime;
256 : struct timespec64 ia_ctime;
257 :
258 : /*
259 : * Not an attribute, but an auxiliary info for filesystems wanting to
260 : * implement an ftruncate() like method. NOTE: filesystem should
261 : * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
262 : */
263 : struct file *ia_file;
264 : };
265 :
266 : /*
267 : * Includes for diskquotas.
268 : */
269 : #include <linux/quota.h>
270 :
271 : /*
272 : * Maximum number of layers of fs stack. Needs to be limited to
273 : * prevent kernel stack overflow
274 : */
275 : #define FILESYSTEM_MAX_STACK_DEPTH 2
276 :
277 : /**
278 : * enum positive_aop_returns - aop return codes with specific semantics
279 : *
280 : * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
281 : * completed, that the page is still locked, and
282 : * should be considered active. The VM uses this hint
283 : * to return the page to the active list -- it won't
284 : * be a candidate for writeback again in the near
285 : * future. Other callers must be careful to unlock
286 : * the page if they get this return. Returned by
287 : * writepage();
288 : *
289 : * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
290 : * unlocked it and the page might have been truncated.
291 : * The caller should back up to acquiring a new page and
292 : * trying again. The aop will be taking reasonable
293 : * precautions not to livelock. If the caller held a page
294 : * reference, it should drop it before retrying. Returned
295 : * by read_folio().
296 : *
297 : * address_space_operation functions return these large constants to indicate
298 : * special semantics to the caller. These are much larger than the bytes in a
299 : * page to allow for functions that return the number of bytes operated on in a
300 : * given page.
301 : */
302 :
303 : enum positive_aop_returns {
304 : AOP_WRITEPAGE_ACTIVATE = 0x80000,
305 : AOP_TRUNCATED_PAGE = 0x80001,
306 : };
307 :
308 : /*
309 : * oh the beauties of C type declarations.
310 : */
311 : struct page;
312 : struct address_space;
313 : struct writeback_control;
314 : struct readahead_control;
315 :
316 : /*
317 : * Write life time hint values.
318 : * Stored in struct inode as u8.
319 : */
320 : enum rw_hint {
321 : WRITE_LIFE_NOT_SET = 0,
322 : WRITE_LIFE_NONE = RWH_WRITE_LIFE_NONE,
323 : WRITE_LIFE_SHORT = RWH_WRITE_LIFE_SHORT,
324 : WRITE_LIFE_MEDIUM = RWH_WRITE_LIFE_MEDIUM,
325 : WRITE_LIFE_LONG = RWH_WRITE_LIFE_LONG,
326 : WRITE_LIFE_EXTREME = RWH_WRITE_LIFE_EXTREME,
327 : };
328 :
329 : /* Match RWF_* bits to IOCB bits */
330 : #define IOCB_HIPRI (__force int) RWF_HIPRI
331 : #define IOCB_DSYNC (__force int) RWF_DSYNC
332 : #define IOCB_SYNC (__force int) RWF_SYNC
333 : #define IOCB_NOWAIT (__force int) RWF_NOWAIT
334 : #define IOCB_APPEND (__force int) RWF_APPEND
335 :
336 : /* non-RWF related bits - start at 16 */
337 : #define IOCB_EVENTFD (1 << 16)
338 : #define IOCB_DIRECT (1 << 17)
339 : #define IOCB_WRITE (1 << 18)
340 : /* iocb->ki_waitq is valid */
341 : #define IOCB_WAITQ (1 << 19)
342 : #define IOCB_NOIO (1 << 20)
343 : /* can use bio alloc cache */
344 : #define IOCB_ALLOC_CACHE (1 << 21)
345 :
346 : /* for use in trace events */
347 : #define TRACE_IOCB_STRINGS \
348 : { IOCB_HIPRI, "HIPRI" }, \
349 : { IOCB_DSYNC, "DSYNC" }, \
350 : { IOCB_SYNC, "SYNC" }, \
351 : { IOCB_NOWAIT, "NOWAIT" }, \
352 : { IOCB_APPEND, "APPEND" }, \
353 : { IOCB_EVENTFD, "EVENTFD"}, \
354 : { IOCB_DIRECT, "DIRECT" }, \
355 : { IOCB_WRITE, "WRITE" }, \
356 : { IOCB_WAITQ, "WAITQ" }, \
357 : { IOCB_NOIO, "NOIO" }, \
358 : { IOCB_ALLOC_CACHE, "ALLOC_CACHE" }
359 :
360 : struct kiocb {
361 : struct file *ki_filp;
362 : loff_t ki_pos;
363 : void (*ki_complete)(struct kiocb *iocb, long ret);
364 : void *private;
365 : int ki_flags;
366 : u16 ki_ioprio; /* See linux/ioprio.h */
367 : struct wait_page_queue *ki_waitq; /* for async buffered IO */
368 : };
369 :
370 : static inline bool is_sync_kiocb(struct kiocb *kiocb)
371 : {
372 : return kiocb->ki_complete == NULL;
373 : }
374 :
375 : struct address_space_operations {
376 : int (*writepage)(struct page *page, struct writeback_control *wbc);
377 : int (*read_folio)(struct file *, struct folio *);
378 :
379 : /* Write back some dirty pages from this mapping. */
380 : int (*writepages)(struct address_space *, struct writeback_control *);
381 :
382 : /* Mark a folio dirty. Return true if this dirtied it */
383 : bool (*dirty_folio)(struct address_space *, struct folio *);
384 :
385 : void (*readahead)(struct readahead_control *);
386 :
387 : int (*write_begin)(struct file *, struct address_space *mapping,
388 : loff_t pos, unsigned len,
389 : struct page **pagep, void **fsdata);
390 : int (*write_end)(struct file *, struct address_space *mapping,
391 : loff_t pos, unsigned len, unsigned copied,
392 : struct page *page, void *fsdata);
393 :
394 : /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
395 : sector_t (*bmap)(struct address_space *, sector_t);
396 : void (*invalidate_folio) (struct folio *, size_t offset, size_t len);
397 : bool (*release_folio)(struct folio *, gfp_t);
398 : void (*free_folio)(struct folio *folio);
399 : ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
400 : /*
401 : * migrate the contents of a folio to the specified target. If
402 : * migrate_mode is MIGRATE_ASYNC, it must not block.
403 : */
404 : int (*migrate_folio)(struct address_space *, struct folio *dst,
405 : struct folio *src, enum migrate_mode);
406 : int (*launder_folio)(struct folio *);
407 : bool (*is_partially_uptodate) (struct folio *, size_t from,
408 : size_t count);
409 : void (*is_dirty_writeback) (struct folio *, bool *dirty, bool *wb);
410 : int (*error_remove_page)(struct address_space *, struct page *);
411 :
412 : /* swapfile support */
413 : int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
414 : sector_t *span);
415 : void (*swap_deactivate)(struct file *file);
416 : int (*swap_rw)(struct kiocb *iocb, struct iov_iter *iter);
417 : };
418 :
419 : extern const struct address_space_operations empty_aops;
420 :
421 : /**
422 : * struct address_space - Contents of a cacheable, mappable object.
423 : * @host: Owner, either the inode or the block_device.
424 : * @i_pages: Cached pages.
425 : * @invalidate_lock: Guards coherency between page cache contents and
426 : * file offset->disk block mappings in the filesystem during invalidates.
427 : * It is also used to block modification of page cache contents through
428 : * memory mappings.
429 : * @gfp_mask: Memory allocation flags to use for allocating pages.
430 : * @i_mmap_writable: Number of VM_SHARED mappings.
431 : * @nr_thps: Number of THPs in the pagecache (non-shmem only).
432 : * @i_mmap: Tree of private and shared mappings.
433 : * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
434 : * @nrpages: Number of page entries, protected by the i_pages lock.
435 : * @writeback_index: Writeback starts here.
436 : * @a_ops: Methods.
437 : * @flags: Error bits and flags (AS_*).
438 : * @wb_err: The most recent error which has occurred.
439 : * @private_lock: For use by the owner of the address_space.
440 : * @private_list: For use by the owner of the address_space.
441 : * @private_data: For use by the owner of the address_space.
442 : */
443 : struct address_space {
444 : struct inode *host;
445 : struct xarray i_pages;
446 : struct rw_semaphore invalidate_lock;
447 : gfp_t gfp_mask;
448 : atomic_t i_mmap_writable;
449 : #ifdef CONFIG_READ_ONLY_THP_FOR_FS
450 : /* number of thp, only for non-shmem files */
451 : atomic_t nr_thps;
452 : #endif
453 : struct rb_root_cached i_mmap;
454 : struct rw_semaphore i_mmap_rwsem;
455 : unsigned long nrpages;
456 : pgoff_t writeback_index;
457 : const struct address_space_operations *a_ops;
458 : unsigned long flags;
459 : errseq_t wb_err;
460 : spinlock_t private_lock;
461 : struct list_head private_list;
462 : void *private_data;
463 : } __attribute__((aligned(sizeof(long)))) __randomize_layout;
464 : /*
465 : * On most architectures that alignment is already the case; but
466 : * must be enforced here for CRIS, to let the least significant bit
467 : * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
468 : */
469 :
470 : /* XArray tags, for tagging dirty and writeback pages in the pagecache. */
471 : #define PAGECACHE_TAG_DIRTY XA_MARK_0
472 : #define PAGECACHE_TAG_WRITEBACK XA_MARK_1
473 : #define PAGECACHE_TAG_TOWRITE XA_MARK_2
474 :
475 : /*
476 : * Returns true if any of the pages in the mapping are marked with the tag.
477 : */
478 : static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
479 : {
480 0 : return xa_marked(&mapping->i_pages, tag);
481 : }
482 :
483 : static inline void i_mmap_lock_write(struct address_space *mapping)
484 : {
485 0 : down_write(&mapping->i_mmap_rwsem);
486 : }
487 :
488 : static inline int i_mmap_trylock_write(struct address_space *mapping)
489 : {
490 : return down_write_trylock(&mapping->i_mmap_rwsem);
491 : }
492 :
493 : static inline void i_mmap_unlock_write(struct address_space *mapping)
494 : {
495 0 : up_write(&mapping->i_mmap_rwsem);
496 : }
497 :
498 : static inline int i_mmap_trylock_read(struct address_space *mapping)
499 : {
500 0 : return down_read_trylock(&mapping->i_mmap_rwsem);
501 : }
502 :
503 : static inline void i_mmap_lock_read(struct address_space *mapping)
504 : {
505 0 : down_read(&mapping->i_mmap_rwsem);
506 : }
507 :
508 : static inline void i_mmap_unlock_read(struct address_space *mapping)
509 : {
510 0 : up_read(&mapping->i_mmap_rwsem);
511 : }
512 :
513 : static inline void i_mmap_assert_locked(struct address_space *mapping)
514 : {
515 : lockdep_assert_held(&mapping->i_mmap_rwsem);
516 : }
517 :
518 : static inline void i_mmap_assert_write_locked(struct address_space *mapping)
519 : {
520 : lockdep_assert_held_write(&mapping->i_mmap_rwsem);
521 : }
522 :
523 : /*
524 : * Might pages of this file be mapped into userspace?
525 : */
526 : static inline int mapping_mapped(struct address_space *mapping)
527 : {
528 : return !RB_EMPTY_ROOT(&mapping->i_mmap.rb_root);
529 : }
530 :
531 : /*
532 : * Might pages of this file have been modified in userspace?
533 : * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap
534 : * marks vma as VM_SHARED if it is shared, and the file was opened for
535 : * writing i.e. vma may be mprotected writable even if now readonly.
536 : *
537 : * If i_mmap_writable is negative, no new writable mappings are allowed. You
538 : * can only deny writable mappings, if none exists right now.
539 : */
540 : static inline int mapping_writably_mapped(struct address_space *mapping)
541 : {
542 0 : return atomic_read(&mapping->i_mmap_writable) > 0;
543 : }
544 :
545 : static inline int mapping_map_writable(struct address_space *mapping)
546 : {
547 0 : return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
548 0 : 0 : -EPERM;
549 : }
550 :
551 : static inline void mapping_unmap_writable(struct address_space *mapping)
552 : {
553 0 : atomic_dec(&mapping->i_mmap_writable);
554 : }
555 :
556 : static inline int mapping_deny_writable(struct address_space *mapping)
557 : {
558 : return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
559 : 0 : -EBUSY;
560 : }
561 :
562 : static inline void mapping_allow_writable(struct address_space *mapping)
563 : {
564 0 : atomic_inc(&mapping->i_mmap_writable);
565 : }
566 :
567 : /*
568 : * Use sequence counter to get consistent i_size on 32-bit processors.
569 : */
570 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
571 : #include <linux/seqlock.h>
572 : #define __NEED_I_SIZE_ORDERED
573 : #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
574 : #else
575 : #define i_size_ordered_init(inode) do { } while (0)
576 : #endif
577 :
578 : struct posix_acl;
579 : #define ACL_NOT_CACHED ((void *)(-1))
580 : /*
581 : * ACL_DONT_CACHE is for stacked filesystems, that rely on underlying fs to
582 : * cache the ACL. This also means that ->get_inode_acl() can be called in RCU
583 : * mode with the LOOKUP_RCU flag.
584 : */
585 : #define ACL_DONT_CACHE ((void *)(-3))
586 :
587 : static inline struct posix_acl *
588 : uncached_acl_sentinel(struct task_struct *task)
589 : {
590 : return (void *)task + 1;
591 : }
592 :
593 : static inline bool
594 : is_uncached_acl(struct posix_acl *acl)
595 : {
596 : return (long)acl & 1;
597 : }
598 :
599 : #define IOP_FASTPERM 0x0001
600 : #define IOP_LOOKUP 0x0002
601 : #define IOP_NOFOLLOW 0x0004
602 : #define IOP_XATTR 0x0008
603 : #define IOP_DEFAULT_READLINK 0x0010
604 :
605 : struct fsnotify_mark_connector;
606 :
607 : /*
608 : * Keep mostly read-only and often accessed (especially for
609 : * the RCU path lookup and 'stat' data) fields at the beginning
610 : * of the 'struct inode'
611 : */
612 : struct inode {
613 : umode_t i_mode;
614 : unsigned short i_opflags;
615 : kuid_t i_uid;
616 : kgid_t i_gid;
617 : unsigned int i_flags;
618 :
619 : #ifdef CONFIG_FS_POSIX_ACL
620 : struct posix_acl *i_acl;
621 : struct posix_acl *i_default_acl;
622 : #endif
623 :
624 : const struct inode_operations *i_op;
625 : struct super_block *i_sb;
626 : struct address_space *i_mapping;
627 :
628 : #ifdef CONFIG_SECURITY
629 : void *i_security;
630 : #endif
631 :
632 : /* Stat data, not accessed from path walking */
633 : unsigned long i_ino;
634 : /*
635 : * Filesystems may only read i_nlink directly. They shall use the
636 : * following functions for modification:
637 : *
638 : * (set|clear|inc|drop)_nlink
639 : * inode_(inc|dec)_link_count
640 : */
641 : union {
642 : const unsigned int i_nlink;
643 : unsigned int __i_nlink;
644 : };
645 : dev_t i_rdev;
646 : loff_t i_size;
647 : struct timespec64 i_atime;
648 : struct timespec64 i_mtime;
649 : struct timespec64 i_ctime;
650 : spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
651 : unsigned short i_bytes;
652 : u8 i_blkbits;
653 : u8 i_write_hint;
654 : blkcnt_t i_blocks;
655 :
656 : #ifdef __NEED_I_SIZE_ORDERED
657 : seqcount_t i_size_seqcount;
658 : #endif
659 :
660 : /* Misc */
661 : unsigned long i_state;
662 : struct rw_semaphore i_rwsem;
663 :
664 : unsigned long dirtied_when; /* jiffies of first dirtying */
665 : unsigned long dirtied_time_when;
666 :
667 : struct hlist_node i_hash;
668 : struct list_head i_io_list; /* backing dev IO list */
669 : #ifdef CONFIG_CGROUP_WRITEBACK
670 : struct bdi_writeback *i_wb; /* the associated cgroup wb */
671 :
672 : /* foreign inode detection, see wbc_detach_inode() */
673 : int i_wb_frn_winner;
674 : u16 i_wb_frn_avg_time;
675 : u16 i_wb_frn_history;
676 : #endif
677 : struct list_head i_lru; /* inode LRU list */
678 : struct list_head i_sb_list;
679 : struct list_head i_wb_list; /* backing dev writeback list */
680 : union {
681 : struct hlist_head i_dentry;
682 : struct rcu_head i_rcu;
683 : };
684 : atomic64_t i_version;
685 : atomic64_t i_sequence; /* see futex */
686 : atomic_t i_count;
687 : atomic_t i_dio_count;
688 : atomic_t i_writecount;
689 : #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
690 : atomic_t i_readcount; /* struct files open RO */
691 : #endif
692 : union {
693 : const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
694 : void (*free_inode)(struct inode *);
695 : };
696 : struct file_lock_context *i_flctx;
697 : struct address_space i_data;
698 : struct list_head i_devices;
699 : union {
700 : struct pipe_inode_info *i_pipe;
701 : struct cdev *i_cdev;
702 : char *i_link;
703 : unsigned i_dir_seq;
704 : };
705 :
706 : __u32 i_generation;
707 :
708 : #ifdef CONFIG_FSNOTIFY
709 : __u32 i_fsnotify_mask; /* all events this inode cares about */
710 : struct fsnotify_mark_connector __rcu *i_fsnotify_marks;
711 : #endif
712 :
713 : #ifdef CONFIG_FS_ENCRYPTION
714 : struct fscrypt_info *i_crypt_info;
715 : #endif
716 :
717 : #ifdef CONFIG_FS_VERITY
718 : struct fsverity_info *i_verity_info;
719 : #endif
720 :
721 : void *i_private; /* fs or device private pointer */
722 : } __randomize_layout;
723 :
724 : struct timespec64 timestamp_truncate(struct timespec64 t, struct inode *inode);
725 :
726 : static inline unsigned int i_blocksize(const struct inode *node)
727 : {
728 0 : return (1 << node->i_blkbits);
729 : }
730 :
731 : static inline int inode_unhashed(struct inode *inode)
732 : {
733 88 : return hlist_unhashed(&inode->i_hash);
734 : }
735 :
736 : /*
737 : * __mark_inode_dirty expects inodes to be hashed. Since we don't
738 : * want special inodes in the fileset inode space, we make them
739 : * appear hashed, but do not put on any lists. hlist_del()
740 : * will work fine and require no locking.
741 : */
742 : static inline void inode_fake_hash(struct inode *inode)
743 : {
744 : hlist_add_fake(&inode->i_hash);
745 : }
746 :
747 : /*
748 : * inode->i_mutex nesting subclasses for the lock validator:
749 : *
750 : * 0: the object of the current VFS operation
751 : * 1: parent
752 : * 2: child/target
753 : * 3: xattr
754 : * 4: second non-directory
755 : * 5: second parent (when locking independent directories in rename)
756 : *
757 : * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
758 : * non-directories at once.
759 : *
760 : * The locking order between these classes is
761 : * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
762 : */
763 : enum inode_i_mutex_lock_class
764 : {
765 : I_MUTEX_NORMAL,
766 : I_MUTEX_PARENT,
767 : I_MUTEX_CHILD,
768 : I_MUTEX_XATTR,
769 : I_MUTEX_NONDIR2,
770 : I_MUTEX_PARENT2,
771 : };
772 :
773 : static inline void inode_lock(struct inode *inode)
774 : {
775 2 : down_write(&inode->i_rwsem);
776 : }
777 :
778 : static inline void inode_unlock(struct inode *inode)
779 : {
780 5 : up_write(&inode->i_rwsem);
781 : }
782 :
783 : static inline void inode_lock_shared(struct inode *inode)
784 : {
785 0 : down_read(&inode->i_rwsem);
786 : }
787 :
788 : static inline void inode_unlock_shared(struct inode *inode)
789 : {
790 0 : up_read(&inode->i_rwsem);
791 : }
792 :
793 : static inline int inode_trylock(struct inode *inode)
794 : {
795 0 : return down_write_trylock(&inode->i_rwsem);
796 : }
797 :
798 : static inline int inode_trylock_shared(struct inode *inode)
799 : {
800 0 : return down_read_trylock(&inode->i_rwsem);
801 : }
802 :
803 : static inline int inode_is_locked(struct inode *inode)
804 : {
805 0 : return rwsem_is_locked(&inode->i_rwsem);
806 : }
807 :
808 : static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
809 : {
810 3 : down_write_nested(&inode->i_rwsem, subclass);
811 : }
812 :
813 : static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass)
814 : {
815 : down_read_nested(&inode->i_rwsem, subclass);
816 : }
817 :
818 : static inline void filemap_invalidate_lock(struct address_space *mapping)
819 : {
820 0 : down_write(&mapping->invalidate_lock);
821 : }
822 :
823 : static inline void filemap_invalidate_unlock(struct address_space *mapping)
824 : {
825 0 : up_write(&mapping->invalidate_lock);
826 : }
827 :
828 : static inline void filemap_invalidate_lock_shared(struct address_space *mapping)
829 : {
830 0 : down_read(&mapping->invalidate_lock);
831 : }
832 :
833 : static inline int filemap_invalidate_trylock_shared(
834 : struct address_space *mapping)
835 : {
836 0 : return down_read_trylock(&mapping->invalidate_lock);
837 : }
838 :
839 : static inline void filemap_invalidate_unlock_shared(
840 : struct address_space *mapping)
841 : {
842 0 : up_read(&mapping->invalidate_lock);
843 : }
844 :
845 : void lock_two_nondirectories(struct inode *, struct inode*);
846 : void unlock_two_nondirectories(struct inode *, struct inode*);
847 :
848 : void filemap_invalidate_lock_two(struct address_space *mapping1,
849 : struct address_space *mapping2);
850 : void filemap_invalidate_unlock_two(struct address_space *mapping1,
851 : struct address_space *mapping2);
852 :
853 :
854 : /*
855 : * NOTE: in a 32bit arch with a preemptable kernel and
856 : * an UP compile the i_size_read/write must be atomic
857 : * with respect to the local cpu (unlike with preempt disabled),
858 : * but they don't need to be atomic with respect to other cpus like in
859 : * true SMP (so they need either to either locally disable irq around
860 : * the read or for example on x86 they can be still implemented as a
861 : * cmpxchg8b without the need of the lock prefix). For SMP compiles
862 : * and 64bit archs it makes no difference if preempt is enabled or not.
863 : */
864 : static inline loff_t i_size_read(const struct inode *inode)
865 : {
866 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
867 : loff_t i_size;
868 : unsigned int seq;
869 :
870 : do {
871 : seq = read_seqcount_begin(&inode->i_size_seqcount);
872 : i_size = inode->i_size;
873 : } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
874 : return i_size;
875 : #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
876 : loff_t i_size;
877 :
878 : preempt_disable();
879 : i_size = inode->i_size;
880 : preempt_enable();
881 : return i_size;
882 : #else
883 : return inode->i_size;
884 : #endif
885 : }
886 :
887 : /*
888 : * NOTE: unlike i_size_read(), i_size_write() does need locking around it
889 : * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
890 : * can be lost, resulting in subsequent i_size_read() calls spinning forever.
891 : */
892 : static inline void i_size_write(struct inode *inode, loff_t i_size)
893 : {
894 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
895 : preempt_disable();
896 : write_seqcount_begin(&inode->i_size_seqcount);
897 : inode->i_size = i_size;
898 : write_seqcount_end(&inode->i_size_seqcount);
899 : preempt_enable();
900 : #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
901 : preempt_disable();
902 : inode->i_size = i_size;
903 : preempt_enable();
904 : #else
905 0 : inode->i_size = i_size;
906 : #endif
907 : }
908 :
909 : static inline unsigned iminor(const struct inode *inode)
910 : {
911 0 : return MINOR(inode->i_rdev);
912 : }
913 :
914 : static inline unsigned imajor(const struct inode *inode)
915 : {
916 0 : return MAJOR(inode->i_rdev);
917 : }
918 :
919 : struct fown_struct {
920 : rwlock_t lock; /* protects pid, uid, euid fields */
921 : struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
922 : enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
923 : kuid_t uid, euid; /* uid/euid of process setting the owner */
924 : int signum; /* posix.1b rt signal to be delivered on IO */
925 : };
926 :
927 : /**
928 : * struct file_ra_state - Track a file's readahead state.
929 : * @start: Where the most recent readahead started.
930 : * @size: Number of pages read in the most recent readahead.
931 : * @async_size: Numer of pages that were/are not needed immediately
932 : * and so were/are genuinely "ahead". Start next readahead when
933 : * the first of these pages is accessed.
934 : * @ra_pages: Maximum size of a readahead request, copied from the bdi.
935 : * @mmap_miss: How many mmap accesses missed in the page cache.
936 : * @prev_pos: The last byte in the most recent read request.
937 : *
938 : * When this structure is passed to ->readahead(), the "most recent"
939 : * readahead means the current readahead.
940 : */
941 : struct file_ra_state {
942 : pgoff_t start;
943 : unsigned int size;
944 : unsigned int async_size;
945 : unsigned int ra_pages;
946 : unsigned int mmap_miss;
947 : loff_t prev_pos;
948 : };
949 :
950 : /*
951 : * Check if @index falls in the readahead windows.
952 : */
953 : static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
954 : {
955 : return (index >= ra->start &&
956 : index < ra->start + ra->size);
957 : }
958 :
959 : struct file {
960 : union {
961 : struct llist_node f_llist;
962 : struct rcu_head f_rcuhead;
963 : unsigned int f_iocb_flags;
964 : };
965 : struct path f_path;
966 : struct inode *f_inode; /* cached value */
967 : const struct file_operations *f_op;
968 :
969 : /*
970 : * Protects f_ep, f_flags.
971 : * Must not be taken from IRQ context.
972 : */
973 : spinlock_t f_lock;
974 : atomic_long_t f_count;
975 : unsigned int f_flags;
976 : fmode_t f_mode;
977 : struct mutex f_pos_lock;
978 : loff_t f_pos;
979 : struct fown_struct f_owner;
980 : const struct cred *f_cred;
981 : struct file_ra_state f_ra;
982 :
983 : u64 f_version;
984 : #ifdef CONFIG_SECURITY
985 : void *f_security;
986 : #endif
987 : /* needed for tty driver, and maybe others */
988 : void *private_data;
989 :
990 : #ifdef CONFIG_EPOLL
991 : /* Used by fs/eventpoll.c to link all the hooks to this file */
992 : struct hlist_head *f_ep;
993 : #endif /* #ifdef CONFIG_EPOLL */
994 : struct address_space *f_mapping;
995 : errseq_t f_wb_err;
996 : errseq_t f_sb_err; /* for syncfs */
997 : } __randomize_layout
998 : __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
999 :
1000 : struct file_handle {
1001 : __u32 handle_bytes;
1002 : int handle_type;
1003 : /* file identifier */
1004 : unsigned char f_handle[];
1005 : };
1006 :
1007 : static inline struct file *get_file(struct file *f)
1008 : {
1009 0 : atomic_long_inc(&f->f_count);
1010 : return f;
1011 : }
1012 : #define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
1013 : #define file_count(x) atomic_long_read(&(x)->f_count)
1014 :
1015 : #define MAX_NON_LFS ((1UL<<31) - 1)
1016 :
1017 : /* Page cache limit. The filesystems should put that into their s_maxbytes
1018 : limits, otherwise bad things can happen in VM. */
1019 : #if BITS_PER_LONG==32
1020 : #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
1021 : #elif BITS_PER_LONG==64
1022 : #define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
1023 : #endif
1024 :
1025 : /* legacy typedef, should eventually be removed */
1026 : typedef void *fl_owner_t;
1027 :
1028 : struct file_lock;
1029 :
1030 : /* The following constant reflects the upper bound of the file/locking space */
1031 : #ifndef OFFSET_MAX
1032 : #define OFFSET_MAX type_max(loff_t)
1033 : #define OFFT_OFFSET_MAX type_max(off_t)
1034 : #endif
1035 :
1036 : extern void send_sigio(struct fown_struct *fown, int fd, int band);
1037 :
1038 : static inline struct inode *file_inode(const struct file *f)
1039 : {
1040 : return f->f_inode;
1041 : }
1042 :
1043 : static inline struct dentry *file_dentry(const struct file *file)
1044 : {
1045 0 : return d_real(file->f_path.dentry, file_inode(file));
1046 : }
1047 :
1048 : struct fasync_struct {
1049 : rwlock_t fa_lock;
1050 : int magic;
1051 : int fa_fd;
1052 : struct fasync_struct *fa_next; /* singly linked list */
1053 : struct file *fa_file;
1054 : struct rcu_head fa_rcu;
1055 : };
1056 :
1057 : #define FASYNC_MAGIC 0x4601
1058 :
1059 : /* SMP safe fasync helpers: */
1060 : extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1061 : extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1062 : extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1063 : extern struct fasync_struct *fasync_alloc(void);
1064 : extern void fasync_free(struct fasync_struct *);
1065 :
1066 : /* can be called from interrupts */
1067 : extern void kill_fasync(struct fasync_struct **, int, int);
1068 :
1069 : extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1070 : extern int f_setown(struct file *filp, unsigned long arg, int force);
1071 : extern void f_delown(struct file *filp);
1072 : extern pid_t f_getown(struct file *filp);
1073 : extern int send_sigurg(struct fown_struct *fown);
1074 :
1075 : /*
1076 : * sb->s_flags. Note that these mirror the equivalent MS_* flags where
1077 : * represented in both.
1078 : */
1079 : #define SB_RDONLY BIT(0) /* Mount read-only */
1080 : #define SB_NOSUID BIT(1) /* Ignore suid and sgid bits */
1081 : #define SB_NODEV BIT(2) /* Disallow access to device special files */
1082 : #define SB_NOEXEC BIT(3) /* Disallow program execution */
1083 : #define SB_SYNCHRONOUS BIT(4) /* Writes are synced at once */
1084 : #define SB_MANDLOCK BIT(6) /* Allow mandatory locks on an FS */
1085 : #define SB_DIRSYNC BIT(7) /* Directory modifications are synchronous */
1086 : #define SB_NOATIME BIT(10) /* Do not update access times. */
1087 : #define SB_NODIRATIME BIT(11) /* Do not update directory access times */
1088 : #define SB_SILENT BIT(15)
1089 : #define SB_POSIXACL BIT(16) /* VFS does not apply the umask */
1090 : #define SB_INLINECRYPT BIT(17) /* Use blk-crypto for encrypted files */
1091 : #define SB_KERNMOUNT BIT(22) /* this is a kern_mount call */
1092 : #define SB_I_VERSION BIT(23) /* Update inode I_version field */
1093 : #define SB_LAZYTIME BIT(25) /* Update the on-disk [acm]times lazily */
1094 :
1095 : /* These sb flags are internal to the kernel */
1096 : #define SB_SUBMOUNT BIT(26)
1097 : #define SB_FORCE BIT(27)
1098 : #define SB_NOSEC BIT(28)
1099 : #define SB_BORN BIT(29)
1100 : #define SB_ACTIVE BIT(30)
1101 : #define SB_NOUSER BIT(31)
1102 :
1103 : /* These flags relate to encoding and casefolding */
1104 : #define SB_ENC_STRICT_MODE_FL (1 << 0)
1105 :
1106 : #define sb_has_strict_encoding(sb) \
1107 : (sb->s_encoding_flags & SB_ENC_STRICT_MODE_FL)
1108 :
1109 : /*
1110 : * Umount options
1111 : */
1112 :
1113 : #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1114 : #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1115 : #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1116 : #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1117 : #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1118 :
1119 : /* sb->s_iflags */
1120 : #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1121 : #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1122 : #define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
1123 : #define SB_I_STABLE_WRITES 0x00000008 /* don't modify blks until WB is done */
1124 :
1125 : /* sb->s_iflags to limit user namespace mounts */
1126 : #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
1127 : #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
1128 : #define SB_I_UNTRUSTED_MOUNTER 0x00000040
1129 :
1130 : #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */
1131 : #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */
1132 : #define SB_I_TS_EXPIRY_WARNED 0x00000400 /* warned about timestamp range expiry */
1133 : #define SB_I_RETIRED 0x00000800 /* superblock shouldn't be reused */
1134 :
1135 : /* Possible states of 'frozen' field */
1136 : enum {
1137 : SB_UNFROZEN = 0, /* FS is unfrozen */
1138 : SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1139 : SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1140 : SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1141 : * internal threads if needed) */
1142 : SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1143 : };
1144 :
1145 : #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1146 :
1147 : struct sb_writers {
1148 : int frozen; /* Is sb frozen? */
1149 : wait_queue_head_t wait_unfrozen; /* wait for thaw */
1150 : struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
1151 : };
1152 :
1153 : struct super_block {
1154 : struct list_head s_list; /* Keep this first */
1155 : dev_t s_dev; /* search index; _not_ kdev_t */
1156 : unsigned char s_blocksize_bits;
1157 : unsigned long s_blocksize;
1158 : loff_t s_maxbytes; /* Max file size */
1159 : struct file_system_type *s_type;
1160 : const struct super_operations *s_op;
1161 : const struct dquot_operations *dq_op;
1162 : const struct quotactl_ops *s_qcop;
1163 : const struct export_operations *s_export_op;
1164 : unsigned long s_flags;
1165 : unsigned long s_iflags; /* internal SB_I_* flags */
1166 : unsigned long s_magic;
1167 : struct dentry *s_root;
1168 : struct rw_semaphore s_umount;
1169 : int s_count;
1170 : atomic_t s_active;
1171 : #ifdef CONFIG_SECURITY
1172 : void *s_security;
1173 : #endif
1174 : const struct xattr_handler **s_xattr;
1175 : #ifdef CONFIG_FS_ENCRYPTION
1176 : const struct fscrypt_operations *s_cop;
1177 : struct fscrypt_keyring *s_master_keys; /* master crypto keys in use */
1178 : #endif
1179 : #ifdef CONFIG_FS_VERITY
1180 : const struct fsverity_operations *s_vop;
1181 : #endif
1182 : #if IS_ENABLED(CONFIG_UNICODE)
1183 : struct unicode_map *s_encoding;
1184 : __u16 s_encoding_flags;
1185 : #endif
1186 : struct hlist_bl_head s_roots; /* alternate root dentries for NFS */
1187 : struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1188 : struct block_device *s_bdev;
1189 : struct backing_dev_info *s_bdi;
1190 : struct mtd_info *s_mtd;
1191 : struct hlist_node s_instances;
1192 : unsigned int s_quota_types; /* Bitmask of supported quota types */
1193 : struct quota_info s_dquot; /* Diskquota specific options */
1194 :
1195 : struct sb_writers s_writers;
1196 :
1197 : /*
1198 : * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
1199 : * s_fsnotify_marks together for cache efficiency. They are frequently
1200 : * accessed and rarely modified.
1201 : */
1202 : void *s_fs_info; /* Filesystem private info */
1203 :
1204 : /* Granularity of c/m/atime in ns (cannot be worse than a second) */
1205 : u32 s_time_gran;
1206 : /* Time limits for c/m/atime in seconds */
1207 : time64_t s_time_min;
1208 : time64_t s_time_max;
1209 : #ifdef CONFIG_FSNOTIFY
1210 : __u32 s_fsnotify_mask;
1211 : struct fsnotify_mark_connector __rcu *s_fsnotify_marks;
1212 : #endif
1213 :
1214 : char s_id[32]; /* Informational name */
1215 : uuid_t s_uuid; /* UUID */
1216 :
1217 : unsigned int s_max_links;
1218 : fmode_t s_mode;
1219 :
1220 : /*
1221 : * The next field is for VFS *only*. No filesystems have any business
1222 : * even looking at it. You had been warned.
1223 : */
1224 : struct mutex s_vfs_rename_mutex; /* Kludge */
1225 :
1226 : /*
1227 : * Filesystem subtype. If non-empty the filesystem type field
1228 : * in /proc/mounts will be "type.subtype"
1229 : */
1230 : const char *s_subtype;
1231 :
1232 : const struct dentry_operations *s_d_op; /* default d_op for dentries */
1233 :
1234 : struct shrinker s_shrink; /* per-sb shrinker handle */
1235 :
1236 : /* Number of inodes with nlink == 0 but still referenced */
1237 : atomic_long_t s_remove_count;
1238 :
1239 : /*
1240 : * Number of inode/mount/sb objects that are being watched, note that
1241 : * inodes objects are currently double-accounted.
1242 : */
1243 : atomic_long_t s_fsnotify_connectors;
1244 :
1245 : /* Being remounted read-only */
1246 : int s_readonly_remount;
1247 :
1248 : /* per-sb errseq_t for reporting writeback errors via syncfs */
1249 : errseq_t s_wb_err;
1250 :
1251 : /* AIO completions deferred from interrupt context */
1252 : struct workqueue_struct *s_dio_done_wq;
1253 : struct hlist_head s_pins;
1254 :
1255 : /*
1256 : * Owning user namespace and default context in which to
1257 : * interpret filesystem uids, gids, quotas, device nodes,
1258 : * xattrs and security labels.
1259 : */
1260 : struct user_namespace *s_user_ns;
1261 :
1262 : /*
1263 : * The list_lru structure is essentially just a pointer to a table
1264 : * of per-node lru lists, each of which has its own spinlock.
1265 : * There is no need to put them into separate cachelines.
1266 : */
1267 : struct list_lru s_dentry_lru;
1268 : struct list_lru s_inode_lru;
1269 : struct rcu_head rcu;
1270 : struct work_struct destroy_work;
1271 :
1272 : struct mutex s_sync_lock; /* sync serialisation lock */
1273 :
1274 : /*
1275 : * Indicates how deep in a filesystem stack this SB is
1276 : */
1277 : int s_stack_depth;
1278 :
1279 : /* s_inode_list_lock protects s_inodes */
1280 : spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
1281 : struct list_head s_inodes; /* all inodes */
1282 :
1283 : spinlock_t s_inode_wblist_lock;
1284 : struct list_head s_inodes_wb; /* writeback inodes */
1285 : } __randomize_layout;
1286 :
1287 : static inline struct user_namespace *i_user_ns(const struct inode *inode)
1288 : {
1289 26 : return inode->i_sb->s_user_ns;
1290 : }
1291 :
1292 : /* Helper functions so that in most cases filesystems will
1293 : * not need to deal directly with kuid_t and kgid_t and can
1294 : * instead deal with the raw numeric values that are stored
1295 : * in the filesystem.
1296 : */
1297 : static inline uid_t i_uid_read(const struct inode *inode)
1298 : {
1299 : return from_kuid(i_user_ns(inode), inode->i_uid);
1300 : }
1301 :
1302 : static inline gid_t i_gid_read(const struct inode *inode)
1303 : {
1304 : return from_kgid(i_user_ns(inode), inode->i_gid);
1305 : }
1306 :
1307 : static inline void i_uid_write(struct inode *inode, uid_t uid)
1308 : {
1309 61 : inode->i_uid = make_kuid(i_user_ns(inode), uid);
1310 : }
1311 :
1312 : static inline void i_gid_write(struct inode *inode, gid_t gid)
1313 : {
1314 61 : inode->i_gid = make_kgid(i_user_ns(inode), gid);
1315 : }
1316 :
1317 : /**
1318 : * i_uid_into_vfsuid - map an inode's i_uid down according to an idmapping
1319 : * @idmap: idmap of the mount the inode was found from
1320 : * @inode: inode to map
1321 : *
1322 : * Return: whe inode's i_uid mapped down according to @idmap.
1323 : * If the inode's i_uid has no mapping INVALID_VFSUID is returned.
1324 : */
1325 : static inline vfsuid_t i_uid_into_vfsuid(struct mnt_idmap *idmap,
1326 : const struct inode *inode)
1327 : {
1328 26 : return make_vfsuid(idmap, i_user_ns(inode), inode->i_uid);
1329 : }
1330 :
1331 : /**
1332 : * i_uid_needs_update - check whether inode's i_uid needs to be updated
1333 : * @idmap: idmap of the mount the inode was found from
1334 : * @attr: the new attributes of @inode
1335 : * @inode: the inode to update
1336 : *
1337 : * Check whether the $inode's i_uid field needs to be updated taking idmapped
1338 : * mounts into account if the filesystem supports it.
1339 : *
1340 : * Return: true if @inode's i_uid field needs to be updated, false if not.
1341 : */
1342 : static inline bool i_uid_needs_update(struct mnt_idmap *idmap,
1343 : const struct iattr *attr,
1344 : const struct inode *inode)
1345 : {
1346 : return ((attr->ia_valid & ATTR_UID) &&
1347 : !vfsuid_eq(attr->ia_vfsuid,
1348 : i_uid_into_vfsuid(idmap, inode)));
1349 : }
1350 :
1351 : /**
1352 : * i_uid_update - update @inode's i_uid field
1353 : * @idmap: idmap of the mount the inode was found from
1354 : * @attr: the new attributes of @inode
1355 : * @inode: the inode to update
1356 : *
1357 : * Safely update @inode's i_uid field translating the vfsuid of any idmapped
1358 : * mount into the filesystem kuid.
1359 : */
1360 : static inline void i_uid_update(struct mnt_idmap *idmap,
1361 : const struct iattr *attr,
1362 : struct inode *inode)
1363 : {
1364 0 : if (attr->ia_valid & ATTR_UID)
1365 0 : inode->i_uid = from_vfsuid(idmap, i_user_ns(inode),
1366 : attr->ia_vfsuid);
1367 : }
1368 :
1369 : /**
1370 : * i_gid_into_vfsgid - map an inode's i_gid down according to an idmapping
1371 : * @idmap: idmap of the mount the inode was found from
1372 : * @inode: inode to map
1373 : *
1374 : * Return: the inode's i_gid mapped down according to @idmap.
1375 : * If the inode's i_gid has no mapping INVALID_VFSGID is returned.
1376 : */
1377 : static inline vfsgid_t i_gid_into_vfsgid(struct mnt_idmap *idmap,
1378 : const struct inode *inode)
1379 : {
1380 6 : return make_vfsgid(idmap, i_user_ns(inode), inode->i_gid);
1381 : }
1382 :
1383 : /**
1384 : * i_gid_needs_update - check whether inode's i_gid needs to be updated
1385 : * @idmap: idmap of the mount the inode was found from
1386 : * @attr: the new attributes of @inode
1387 : * @inode: the inode to update
1388 : *
1389 : * Check whether the $inode's i_gid field needs to be updated taking idmapped
1390 : * mounts into account if the filesystem supports it.
1391 : *
1392 : * Return: true if @inode's i_gid field needs to be updated, false if not.
1393 : */
1394 : static inline bool i_gid_needs_update(struct mnt_idmap *idmap,
1395 : const struct iattr *attr,
1396 : const struct inode *inode)
1397 : {
1398 : return ((attr->ia_valid & ATTR_GID) &&
1399 : !vfsgid_eq(attr->ia_vfsgid,
1400 : i_gid_into_vfsgid(idmap, inode)));
1401 : }
1402 :
1403 : /**
1404 : * i_gid_update - update @inode's i_gid field
1405 : * @idmap: idmap of the mount the inode was found from
1406 : * @attr: the new attributes of @inode
1407 : * @inode: the inode to update
1408 : *
1409 : * Safely update @inode's i_gid field translating the vfsgid of any idmapped
1410 : * mount into the filesystem kgid.
1411 : */
1412 : static inline void i_gid_update(struct mnt_idmap *idmap,
1413 : const struct iattr *attr,
1414 : struct inode *inode)
1415 : {
1416 0 : if (attr->ia_valid & ATTR_GID)
1417 0 : inode->i_gid = from_vfsgid(idmap, i_user_ns(inode),
1418 : attr->ia_vfsgid);
1419 : }
1420 :
1421 : /**
1422 : * inode_fsuid_set - initialize inode's i_uid field with callers fsuid
1423 : * @inode: inode to initialize
1424 : * @idmap: idmap of the mount the inode was found from
1425 : *
1426 : * Initialize the i_uid field of @inode. If the inode was found/created via
1427 : * an idmapped mount map the caller's fsuid according to @idmap.
1428 : */
1429 5 : static inline void inode_fsuid_set(struct inode *inode,
1430 : struct mnt_idmap *idmap)
1431 : {
1432 15 : inode->i_uid = mapped_fsuid(idmap, i_user_ns(inode));
1433 5 : }
1434 :
1435 : /**
1436 : * inode_fsgid_set - initialize inode's i_gid field with callers fsgid
1437 : * @inode: inode to initialize
1438 : * @idmap: idmap of the mount the inode was found from
1439 : *
1440 : * Initialize the i_gid field of @inode. If the inode was found/created via
1441 : * an idmapped mount map the caller's fsgid according to @idmap.
1442 : */
1443 5 : static inline void inode_fsgid_set(struct inode *inode,
1444 : struct mnt_idmap *idmap)
1445 : {
1446 15 : inode->i_gid = mapped_fsgid(idmap, i_user_ns(inode));
1447 5 : }
1448 :
1449 : /**
1450 : * fsuidgid_has_mapping() - check whether caller's fsuid/fsgid is mapped
1451 : * @sb: the superblock we want a mapping in
1452 : * @idmap: idmap of the relevant mount
1453 : *
1454 : * Check whether the caller's fsuid and fsgid have a valid mapping in the
1455 : * s_user_ns of the superblock @sb. If the caller is on an idmapped mount map
1456 : * the caller's fsuid and fsgid according to the @idmap first.
1457 : *
1458 : * Return: true if fsuid and fsgid is mapped, false if not.
1459 : */
1460 3 : static inline bool fsuidgid_has_mapping(struct super_block *sb,
1461 : struct mnt_idmap *idmap)
1462 : {
1463 3 : struct user_namespace *fs_userns = sb->s_user_ns;
1464 : kuid_t kuid;
1465 : kgid_t kgid;
1466 :
1467 3 : kuid = mapped_fsuid(idmap, fs_userns);
1468 3 : if (!uid_valid(kuid))
1469 : return false;
1470 3 : kgid = mapped_fsgid(idmap, fs_userns);
1471 3 : if (!gid_valid(kgid))
1472 : return false;
1473 : return kuid_has_mapping(fs_userns, kuid) &&
1474 : kgid_has_mapping(fs_userns, kgid);
1475 : }
1476 :
1477 : extern struct timespec64 current_time(struct inode *inode);
1478 :
1479 : /*
1480 : * Snapshotting support.
1481 : */
1482 :
1483 : /*
1484 : * These are internal functions, please use sb_start_{write,pagefault,intwrite}
1485 : * instead.
1486 : */
1487 : static inline void __sb_end_write(struct super_block *sb, int level)
1488 : {
1489 3 : percpu_up_read(sb->s_writers.rw_sem + level-1);
1490 : }
1491 :
1492 : static inline void __sb_start_write(struct super_block *sb, int level)
1493 : {
1494 3 : percpu_down_read(sb->s_writers.rw_sem + level - 1);
1495 : }
1496 :
1497 : static inline bool __sb_start_write_trylock(struct super_block *sb, int level)
1498 : {
1499 0 : return percpu_down_read_trylock(sb->s_writers.rw_sem + level - 1);
1500 : }
1501 :
1502 : #define __sb_writers_acquired(sb, lev) \
1503 : percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1504 : #define __sb_writers_release(sb, lev) \
1505 : percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1506 :
1507 : static inline bool sb_write_started(const struct super_block *sb)
1508 : {
1509 : return lockdep_is_held_type(sb->s_writers.rw_sem + SB_FREEZE_WRITE - 1, 1);
1510 : }
1511 :
1512 : /**
1513 : * sb_end_write - drop write access to a superblock
1514 : * @sb: the super we wrote to
1515 : *
1516 : * Decrement number of writers to the filesystem. Wake up possible waiters
1517 : * wanting to freeze the filesystem.
1518 : */
1519 : static inline void sb_end_write(struct super_block *sb)
1520 : {
1521 3 : __sb_end_write(sb, SB_FREEZE_WRITE);
1522 : }
1523 :
1524 : /**
1525 : * sb_end_pagefault - drop write access to a superblock from a page fault
1526 : * @sb: the super we wrote to
1527 : *
1528 : * Decrement number of processes handling write page fault to the filesystem.
1529 : * Wake up possible waiters wanting to freeze the filesystem.
1530 : */
1531 : static inline void sb_end_pagefault(struct super_block *sb)
1532 : {
1533 0 : __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1534 : }
1535 :
1536 : /**
1537 : * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1538 : * @sb: the super we wrote to
1539 : *
1540 : * Decrement fs-internal number of writers to the filesystem. Wake up possible
1541 : * waiters wanting to freeze the filesystem.
1542 : */
1543 : static inline void sb_end_intwrite(struct super_block *sb)
1544 : {
1545 : __sb_end_write(sb, SB_FREEZE_FS);
1546 : }
1547 :
1548 : /**
1549 : * sb_start_write - get write access to a superblock
1550 : * @sb: the super we write to
1551 : *
1552 : * When a process wants to write data or metadata to a file system (i.e. dirty
1553 : * a page or an inode), it should embed the operation in a sb_start_write() -
1554 : * sb_end_write() pair to get exclusion against file system freezing. This
1555 : * function increments number of writers preventing freezing. If the file
1556 : * system is already frozen, the function waits until the file system is
1557 : * thawed.
1558 : *
1559 : * Since freeze protection behaves as a lock, users have to preserve
1560 : * ordering of freeze protection and other filesystem locks. Generally,
1561 : * freeze protection should be the outermost lock. In particular, we have:
1562 : *
1563 : * sb_start_write
1564 : * -> i_mutex (write path, truncate, directory ops, ...)
1565 : * -> s_umount (freeze_super, thaw_super)
1566 : */
1567 : static inline void sb_start_write(struct super_block *sb)
1568 : {
1569 3 : __sb_start_write(sb, SB_FREEZE_WRITE);
1570 : }
1571 :
1572 : static inline bool sb_start_write_trylock(struct super_block *sb)
1573 : {
1574 0 : return __sb_start_write_trylock(sb, SB_FREEZE_WRITE);
1575 : }
1576 :
1577 : /**
1578 : * sb_start_pagefault - get write access to a superblock from a page fault
1579 : * @sb: the super we write to
1580 : *
1581 : * When a process starts handling write page fault, it should embed the
1582 : * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1583 : * exclusion against file system freezing. This is needed since the page fault
1584 : * is going to dirty a page. This function increments number of running page
1585 : * faults preventing freezing. If the file system is already frozen, the
1586 : * function waits until the file system is thawed.
1587 : *
1588 : * Since page fault freeze protection behaves as a lock, users have to preserve
1589 : * ordering of freeze protection and other filesystem locks. It is advised to
1590 : * put sb_start_pagefault() close to mmap_lock in lock ordering. Page fault
1591 : * handling code implies lock dependency:
1592 : *
1593 : * mmap_lock
1594 : * -> sb_start_pagefault
1595 : */
1596 : static inline void sb_start_pagefault(struct super_block *sb)
1597 : {
1598 0 : __sb_start_write(sb, SB_FREEZE_PAGEFAULT);
1599 : }
1600 :
1601 : /**
1602 : * sb_start_intwrite - get write access to a superblock for internal fs purposes
1603 : * @sb: the super we write to
1604 : *
1605 : * This is the third level of protection against filesystem freezing. It is
1606 : * free for use by a filesystem. The only requirement is that it must rank
1607 : * below sb_start_pagefault.
1608 : *
1609 : * For example filesystem can call sb_start_intwrite() when starting a
1610 : * transaction which somewhat eases handling of freezing for internal sources
1611 : * of filesystem changes (internal fs threads, discarding preallocation on file
1612 : * close, etc.).
1613 : */
1614 : static inline void sb_start_intwrite(struct super_block *sb)
1615 : {
1616 : __sb_start_write(sb, SB_FREEZE_FS);
1617 : }
1618 :
1619 : static inline bool sb_start_intwrite_trylock(struct super_block *sb)
1620 : {
1621 : return __sb_start_write_trylock(sb, SB_FREEZE_FS);
1622 : }
1623 :
1624 : bool inode_owner_or_capable(struct mnt_idmap *idmap,
1625 : const struct inode *inode);
1626 :
1627 : /*
1628 : * VFS helper functions..
1629 : */
1630 : int vfs_create(struct mnt_idmap *, struct inode *,
1631 : struct dentry *, umode_t, bool);
1632 : int vfs_mkdir(struct mnt_idmap *, struct inode *,
1633 : struct dentry *, umode_t);
1634 : int vfs_mknod(struct mnt_idmap *, struct inode *, struct dentry *,
1635 : umode_t, dev_t);
1636 : int vfs_symlink(struct mnt_idmap *, struct inode *,
1637 : struct dentry *, const char *);
1638 : int vfs_link(struct dentry *, struct mnt_idmap *, struct inode *,
1639 : struct dentry *, struct inode **);
1640 : int vfs_rmdir(struct mnt_idmap *, struct inode *, struct dentry *);
1641 : int vfs_unlink(struct mnt_idmap *, struct inode *, struct dentry *,
1642 : struct inode **);
1643 :
1644 : /**
1645 : * struct renamedata - contains all information required for renaming
1646 : * @old_mnt_idmap: idmap of the old mount the inode was found from
1647 : * @old_dir: parent of source
1648 : * @old_dentry: source
1649 : * @new_mnt_idmap: idmap of the new mount the inode was found from
1650 : * @new_dir: parent of destination
1651 : * @new_dentry: destination
1652 : * @delegated_inode: returns an inode needing a delegation break
1653 : * @flags: rename flags
1654 : */
1655 : struct renamedata {
1656 : struct mnt_idmap *old_mnt_idmap;
1657 : struct inode *old_dir;
1658 : struct dentry *old_dentry;
1659 : struct mnt_idmap *new_mnt_idmap;
1660 : struct inode *new_dir;
1661 : struct dentry *new_dentry;
1662 : struct inode **delegated_inode;
1663 : unsigned int flags;
1664 : } __randomize_layout;
1665 :
1666 : int vfs_rename(struct renamedata *);
1667 :
1668 : static inline int vfs_whiteout(struct mnt_idmap *idmap,
1669 : struct inode *dir, struct dentry *dentry)
1670 : {
1671 : return vfs_mknod(idmap, dir, dentry, S_IFCHR | WHITEOUT_MODE,
1672 : WHITEOUT_DEV);
1673 : }
1674 :
1675 : struct file *vfs_tmpfile_open(struct mnt_idmap *idmap,
1676 : const struct path *parentpath,
1677 : umode_t mode, int open_flag, const struct cred *cred);
1678 :
1679 : int vfs_mkobj(struct dentry *, umode_t,
1680 : int (*f)(struct dentry *, umode_t, void *),
1681 : void *);
1682 :
1683 : int vfs_fchown(struct file *file, uid_t user, gid_t group);
1684 : int vfs_fchmod(struct file *file, umode_t mode);
1685 : int vfs_utimes(const struct path *path, struct timespec64 *times);
1686 :
1687 : extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1688 :
1689 : #ifdef CONFIG_COMPAT
1690 : extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
1691 : unsigned long arg);
1692 : #else
1693 : #define compat_ptr_ioctl NULL
1694 : #endif
1695 :
1696 : /*
1697 : * VFS file helper functions.
1698 : */
1699 : void inode_init_owner(struct mnt_idmap *idmap, struct inode *inode,
1700 : const struct inode *dir, umode_t mode);
1701 : extern bool may_open_dev(const struct path *path);
1702 : umode_t mode_strip_sgid(struct mnt_idmap *idmap,
1703 : const struct inode *dir, umode_t mode);
1704 :
1705 : /*
1706 : * This is the "filldir" function type, used by readdir() to let
1707 : * the kernel specify what kind of dirent layout it wants to have.
1708 : * This allows the kernel to read directories into kernel space or
1709 : * to have different dirent layouts depending on the binary type.
1710 : * Return 'true' to keep going and 'false' if there are no more entries.
1711 : */
1712 : struct dir_context;
1713 : typedef bool (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
1714 : unsigned);
1715 :
1716 : struct dir_context {
1717 : filldir_t actor;
1718 : loff_t pos;
1719 : };
1720 :
1721 : /*
1722 : * These flags let !MMU mmap() govern direct device mapping vs immediate
1723 : * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1724 : *
1725 : * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1726 : * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1727 : * NOMMU_MAP_READ: Can be mapped for reading
1728 : * NOMMU_MAP_WRITE: Can be mapped for writing
1729 : * NOMMU_MAP_EXEC: Can be mapped for execution
1730 : */
1731 : #define NOMMU_MAP_COPY 0x00000001
1732 : #define NOMMU_MAP_DIRECT 0x00000008
1733 : #define NOMMU_MAP_READ VM_MAYREAD
1734 : #define NOMMU_MAP_WRITE VM_MAYWRITE
1735 : #define NOMMU_MAP_EXEC VM_MAYEXEC
1736 :
1737 : #define NOMMU_VMFLAGS \
1738 : (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1739 :
1740 : /*
1741 : * These flags control the behavior of the remap_file_range function pointer.
1742 : * If it is called with len == 0 that means "remap to end of source file".
1743 : * See Documentation/filesystems/vfs.rst for more details about this call.
1744 : *
1745 : * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate)
1746 : * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request
1747 : */
1748 : #define REMAP_FILE_DEDUP (1 << 0)
1749 : #define REMAP_FILE_CAN_SHORTEN (1 << 1)
1750 :
1751 : /*
1752 : * These flags signal that the caller is ok with altering various aspects of
1753 : * the behavior of the remap operation. The changes must be made by the
1754 : * implementation; the vfs remap helper functions can take advantage of them.
1755 : * Flags in this category exist to preserve the quirky behavior of the hoisted
1756 : * btrfs clone/dedupe ioctls.
1757 : */
1758 : #define REMAP_FILE_ADVISORY (REMAP_FILE_CAN_SHORTEN)
1759 :
1760 : /*
1761 : * These flags control the behavior of vfs_copy_file_range().
1762 : * They are not available to the user via syscall.
1763 : *
1764 : * COPY_FILE_SPLICE: call splice direct instead of fs clone/copy ops
1765 : */
1766 : #define COPY_FILE_SPLICE (1 << 0)
1767 :
1768 : struct iov_iter;
1769 : struct io_uring_cmd;
1770 :
1771 : struct file_operations {
1772 : struct module *owner;
1773 : loff_t (*llseek) (struct file *, loff_t, int);
1774 : ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1775 : ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1776 : ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1777 : ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1778 : int (*iopoll)(struct kiocb *kiocb, struct io_comp_batch *,
1779 : unsigned int flags);
1780 : int (*iterate) (struct file *, struct dir_context *);
1781 : int (*iterate_shared) (struct file *, struct dir_context *);
1782 : __poll_t (*poll) (struct file *, struct poll_table_struct *);
1783 : long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1784 : long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1785 : int (*mmap) (struct file *, struct vm_area_struct *);
1786 : unsigned long mmap_supported_flags;
1787 : int (*open) (struct inode *, struct file *);
1788 : int (*flush) (struct file *, fl_owner_t id);
1789 : int (*release) (struct inode *, struct file *);
1790 : int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1791 : int (*fasync) (int, struct file *, int);
1792 : int (*lock) (struct file *, int, struct file_lock *);
1793 : ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1794 : unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1795 : int (*check_flags)(int);
1796 : int (*flock) (struct file *, int, struct file_lock *);
1797 : ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1798 : ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1799 : int (*setlease)(struct file *, long, struct file_lock **, void **);
1800 : long (*fallocate)(struct file *file, int mode, loff_t offset,
1801 : loff_t len);
1802 : void (*show_fdinfo)(struct seq_file *m, struct file *f);
1803 : #ifndef CONFIG_MMU
1804 : unsigned (*mmap_capabilities)(struct file *);
1805 : #endif
1806 : ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
1807 : loff_t, size_t, unsigned int);
1808 : loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
1809 : struct file *file_out, loff_t pos_out,
1810 : loff_t len, unsigned int remap_flags);
1811 : int (*fadvise)(struct file *, loff_t, loff_t, int);
1812 : int (*uring_cmd)(struct io_uring_cmd *ioucmd, unsigned int issue_flags);
1813 : int (*uring_cmd_iopoll)(struct io_uring_cmd *, struct io_comp_batch *,
1814 : unsigned int poll_flags);
1815 : } __randomize_layout;
1816 :
1817 : struct inode_operations {
1818 : struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1819 : const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
1820 : int (*permission) (struct mnt_idmap *, struct inode *, int);
1821 : struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);
1822 :
1823 : int (*readlink) (struct dentry *, char __user *,int);
1824 :
1825 : int (*create) (struct mnt_idmap *, struct inode *,struct dentry *,
1826 : umode_t, bool);
1827 : int (*link) (struct dentry *,struct inode *,struct dentry *);
1828 : int (*unlink) (struct inode *,struct dentry *);
1829 : int (*symlink) (struct mnt_idmap *, struct inode *,struct dentry *,
1830 : const char *);
1831 : int (*mkdir) (struct mnt_idmap *, struct inode *,struct dentry *,
1832 : umode_t);
1833 : int (*rmdir) (struct inode *,struct dentry *);
1834 : int (*mknod) (struct mnt_idmap *, struct inode *,struct dentry *,
1835 : umode_t,dev_t);
1836 : int (*rename) (struct mnt_idmap *, struct inode *, struct dentry *,
1837 : struct inode *, struct dentry *, unsigned int);
1838 : int (*setattr) (struct mnt_idmap *, struct dentry *, struct iattr *);
1839 : int (*getattr) (struct mnt_idmap *, const struct path *,
1840 : struct kstat *, u32, unsigned int);
1841 : ssize_t (*listxattr) (struct dentry *, char *, size_t);
1842 : int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1843 : u64 len);
1844 : int (*update_time)(struct inode *, struct timespec64 *, int);
1845 : int (*atomic_open)(struct inode *, struct dentry *,
1846 : struct file *, unsigned open_flag,
1847 : umode_t create_mode);
1848 : int (*tmpfile) (struct mnt_idmap *, struct inode *,
1849 : struct file *, umode_t);
1850 : struct posix_acl *(*get_acl)(struct mnt_idmap *, struct dentry *,
1851 : int);
1852 : int (*set_acl)(struct mnt_idmap *, struct dentry *,
1853 : struct posix_acl *, int);
1854 : int (*fileattr_set)(struct mnt_idmap *idmap,
1855 : struct dentry *dentry, struct fileattr *fa);
1856 : int (*fileattr_get)(struct dentry *dentry, struct fileattr *fa);
1857 : } ____cacheline_aligned;
1858 :
1859 : static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
1860 : struct iov_iter *iter)
1861 : {
1862 0 : return file->f_op->read_iter(kio, iter);
1863 : }
1864 :
1865 : static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
1866 : struct iov_iter *iter)
1867 : {
1868 0 : return file->f_op->write_iter(kio, iter);
1869 : }
1870 :
1871 : static inline int call_mmap(struct file *file, struct vm_area_struct *vma)
1872 : {
1873 0 : return file->f_op->mmap(file, vma);
1874 : }
1875 :
1876 : extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1877 : extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1878 : extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
1879 : loff_t, size_t, unsigned int);
1880 : extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in,
1881 : struct file *file_out, loff_t pos_out,
1882 : size_t len, unsigned int flags);
1883 : int __generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
1884 : struct file *file_out, loff_t pos_out,
1885 : loff_t *len, unsigned int remap_flags,
1886 : const struct iomap_ops *dax_read_ops);
1887 : int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
1888 : struct file *file_out, loff_t pos_out,
1889 : loff_t *count, unsigned int remap_flags);
1890 : extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
1891 : struct file *file_out, loff_t pos_out,
1892 : loff_t len, unsigned int remap_flags);
1893 : extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
1894 : struct file *file_out, loff_t pos_out,
1895 : loff_t len, unsigned int remap_flags);
1896 : extern int vfs_dedupe_file_range(struct file *file,
1897 : struct file_dedupe_range *same);
1898 : extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
1899 : struct file *dst_file, loff_t dst_pos,
1900 : loff_t len, unsigned int remap_flags);
1901 :
1902 :
1903 : struct super_operations {
1904 : struct inode *(*alloc_inode)(struct super_block *sb);
1905 : void (*destroy_inode)(struct inode *);
1906 : void (*free_inode)(struct inode *);
1907 :
1908 : void (*dirty_inode) (struct inode *, int flags);
1909 : int (*write_inode) (struct inode *, struct writeback_control *wbc);
1910 : int (*drop_inode) (struct inode *);
1911 : void (*evict_inode) (struct inode *);
1912 : void (*put_super) (struct super_block *);
1913 : int (*sync_fs)(struct super_block *sb, int wait);
1914 : int (*freeze_super) (struct super_block *);
1915 : int (*freeze_fs) (struct super_block *);
1916 : int (*thaw_super) (struct super_block *);
1917 : int (*unfreeze_fs) (struct super_block *);
1918 : int (*statfs) (struct dentry *, struct kstatfs *);
1919 : int (*remount_fs) (struct super_block *, int *, char *);
1920 : void (*umount_begin) (struct super_block *);
1921 :
1922 : int (*show_options)(struct seq_file *, struct dentry *);
1923 : int (*show_devname)(struct seq_file *, struct dentry *);
1924 : int (*show_path)(struct seq_file *, struct dentry *);
1925 : int (*show_stats)(struct seq_file *, struct dentry *);
1926 : #ifdef CONFIG_QUOTA
1927 : ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1928 : ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1929 : struct dquot **(*get_dquots)(struct inode *);
1930 : #endif
1931 : long (*nr_cached_objects)(struct super_block *,
1932 : struct shrink_control *);
1933 : long (*free_cached_objects)(struct super_block *,
1934 : struct shrink_control *);
1935 : };
1936 :
1937 : /*
1938 : * Inode flags - they have no relation to superblock flags now
1939 : */
1940 : #define S_SYNC (1 << 0) /* Writes are synced at once */
1941 : #define S_NOATIME (1 << 1) /* Do not update access times */
1942 : #define S_APPEND (1 << 2) /* Append-only file */
1943 : #define S_IMMUTABLE (1 << 3) /* Immutable file */
1944 : #define S_DEAD (1 << 4) /* removed, but still open directory */
1945 : #define S_NOQUOTA (1 << 5) /* Inode is not counted to quota */
1946 : #define S_DIRSYNC (1 << 6) /* Directory modifications are synchronous */
1947 : #define S_NOCMTIME (1 << 7) /* Do not update file c/mtime */
1948 : #define S_SWAPFILE (1 << 8) /* Do not truncate: swapon got its bmaps */
1949 : #define S_PRIVATE (1 << 9) /* Inode is fs-internal */
1950 : #define S_IMA (1 << 10) /* Inode has an associated IMA struct */
1951 : #define S_AUTOMOUNT (1 << 11) /* Automount/referral quasi-directory */
1952 : #define S_NOSEC (1 << 12) /* no suid or xattr security attributes */
1953 : #ifdef CONFIG_FS_DAX
1954 : #define S_DAX (1 << 13) /* Direct Access, avoiding the page cache */
1955 : #else
1956 : #define S_DAX 0 /* Make all the DAX code disappear */
1957 : #endif
1958 : #define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
1959 : #define S_CASEFOLD (1 << 15) /* Casefolded file */
1960 : #define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
1961 : #define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
1962 :
1963 : /*
1964 : * Note that nosuid etc flags are inode-specific: setting some file-system
1965 : * flags just means all the inodes inherit those flags by default. It might be
1966 : * possible to override it selectively if you really wanted to with some
1967 : * ioctl() that is not currently implemented.
1968 : *
1969 : * Exception: SB_RDONLY is always applied to the entire file system.
1970 : *
1971 : * Unfortunately, it is possible to change a filesystems flags with it mounted
1972 : * with files in use. This means that all of the inodes will not have their
1973 : * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1974 : * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1975 : */
1976 : #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1977 :
1978 28 : static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags & SB_RDONLY; }
1979 : #define IS_RDONLY(inode) sb_rdonly((inode)->i_sb)
1980 : #define IS_SYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS) || \
1981 : ((inode)->i_flags & S_SYNC))
1982 : #define IS_DIRSYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
1983 : ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1984 : #define IS_MANDLOCK(inode) __IS_FLG(inode, SB_MANDLOCK)
1985 : #define IS_NOATIME(inode) __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
1986 : #define IS_I_VERSION(inode) __IS_FLG(inode, SB_I_VERSION)
1987 :
1988 : #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1989 : #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1990 : #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1991 : #define IS_POSIXACL(inode) __IS_FLG(inode, SB_POSIXACL)
1992 :
1993 : #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1994 : #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1995 : #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1996 : #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1997 : #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1998 : #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1999 : #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
2000 : #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
2001 : #define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED)
2002 : #define IS_CASEFOLDED(inode) ((inode)->i_flags & S_CASEFOLD)
2003 : #define IS_VERITY(inode) ((inode)->i_flags & S_VERITY)
2004 :
2005 : #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
2006 : (inode)->i_rdev == WHITEOUT_DEV)
2007 :
2008 3 : static inline bool HAS_UNMAPPED_ID(struct mnt_idmap *idmap,
2009 : struct inode *inode)
2010 : {
2011 6 : return !vfsuid_valid(i_uid_into_vfsuid(idmap, inode)) ||
2012 3 : !vfsgid_valid(i_gid_into_vfsgid(idmap, inode));
2013 : }
2014 :
2015 0 : static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
2016 : {
2017 0 : *kiocb = (struct kiocb) {
2018 : .ki_filp = filp,
2019 0 : .ki_flags = filp->f_iocb_flags,
2020 0 : .ki_ioprio = get_current_ioprio(),
2021 : };
2022 0 : }
2023 :
2024 : static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
2025 : struct file *filp)
2026 : {
2027 : *kiocb = (struct kiocb) {
2028 : .ki_filp = filp,
2029 : .ki_flags = kiocb_src->ki_flags,
2030 : .ki_ioprio = kiocb_src->ki_ioprio,
2031 : .ki_pos = kiocb_src->ki_pos,
2032 : };
2033 : }
2034 :
2035 : /*
2036 : * Inode state bits. Protected by inode->i_lock
2037 : *
2038 : * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
2039 : * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
2040 : *
2041 : * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
2042 : * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
2043 : * various stages of removing an inode.
2044 : *
2045 : * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
2046 : *
2047 : * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
2048 : * fdatasync() (unless I_DIRTY_DATASYNC is also set).
2049 : * Timestamp updates are the usual cause.
2050 : * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
2051 : * these changes separately from I_DIRTY_SYNC so that we
2052 : * don't have to write inode on fdatasync() when only
2053 : * e.g. the timestamps have changed.
2054 : * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
2055 : * I_DIRTY_TIME The inode itself has dirty timestamps, and the
2056 : * lazytime mount option is enabled. We keep track of this
2057 : * separately from I_DIRTY_SYNC in order to implement
2058 : * lazytime. This gets cleared if I_DIRTY_INODE
2059 : * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. But
2060 : * I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already
2061 : * in place because writeback might already be in progress
2062 : * and we don't want to lose the time update
2063 : * I_NEW Serves as both a mutex and completion notification.
2064 : * New inodes set I_NEW. If two processes both create
2065 : * the same inode, one of them will release its inode and
2066 : * wait for I_NEW to be released before returning.
2067 : * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
2068 : * also cause waiting on I_NEW, without I_NEW actually
2069 : * being set. find_inode() uses this to prevent returning
2070 : * nearly-dead inodes.
2071 : * I_WILL_FREE Must be set when calling write_inode_now() if i_count
2072 : * is zero. I_FREEING must be set when I_WILL_FREE is
2073 : * cleared.
2074 : * I_FREEING Set when inode is about to be freed but still has dirty
2075 : * pages or buffers attached or the inode itself is still
2076 : * dirty.
2077 : * I_CLEAR Added by clear_inode(). In this state the inode is
2078 : * clean and can be destroyed. Inode keeps I_FREEING.
2079 : *
2080 : * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
2081 : * prohibited for many purposes. iget() must wait for
2082 : * the inode to be completely released, then create it
2083 : * anew. Other functions will just ignore such inodes,
2084 : * if appropriate. I_NEW is used for waiting.
2085 : *
2086 : * I_SYNC Writeback of inode is running. The bit is set during
2087 : * data writeback, and cleared with a wakeup on the bit
2088 : * address once it is done. The bit is also used to pin
2089 : * the inode in memory for flusher thread.
2090 : *
2091 : * I_REFERENCED Marks the inode as recently references on the LRU list.
2092 : *
2093 : * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
2094 : *
2095 : * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
2096 : * synchronize competing switching instances and to tell
2097 : * wb stat updates to grab the i_pages lock. See
2098 : * inode_switch_wbs_work_fn() for details.
2099 : *
2100 : * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
2101 : * and work dirs among overlayfs mounts.
2102 : *
2103 : * I_CREATING New object's inode in the middle of setting up.
2104 : *
2105 : * I_DONTCACHE Evict inode as soon as it is not used anymore.
2106 : *
2107 : * I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
2108 : * Used to detect that mark_inode_dirty() should not move
2109 : * inode between dirty lists.
2110 : *
2111 : * I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
2112 : *
2113 : * Q: What is the difference between I_WILL_FREE and I_FREEING?
2114 : */
2115 : #define I_DIRTY_SYNC (1 << 0)
2116 : #define I_DIRTY_DATASYNC (1 << 1)
2117 : #define I_DIRTY_PAGES (1 << 2)
2118 : #define __I_NEW 3
2119 : #define I_NEW (1 << __I_NEW)
2120 : #define I_WILL_FREE (1 << 4)
2121 : #define I_FREEING (1 << 5)
2122 : #define I_CLEAR (1 << 6)
2123 : #define __I_SYNC 7
2124 : #define I_SYNC (1 << __I_SYNC)
2125 : #define I_REFERENCED (1 << 8)
2126 : #define __I_DIO_WAKEUP 9
2127 : #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
2128 : #define I_LINKABLE (1 << 10)
2129 : #define I_DIRTY_TIME (1 << 11)
2130 : #define I_WB_SWITCH (1 << 13)
2131 : #define I_OVL_INUSE (1 << 14)
2132 : #define I_CREATING (1 << 15)
2133 : #define I_DONTCACHE (1 << 16)
2134 : #define I_SYNC_QUEUED (1 << 17)
2135 : #define I_PINNING_FSCACHE_WB (1 << 18)
2136 :
2137 : #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
2138 : #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
2139 : #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
2140 :
2141 : extern void __mark_inode_dirty(struct inode *, int);
2142 : static inline void mark_inode_dirty(struct inode *inode)
2143 : {
2144 0 : __mark_inode_dirty(inode, I_DIRTY);
2145 : }
2146 :
2147 : static inline void mark_inode_dirty_sync(struct inode *inode)
2148 : {
2149 0 : __mark_inode_dirty(inode, I_DIRTY_SYNC);
2150 : }
2151 :
2152 : /*
2153 : * Returns true if the given inode itself only has dirty timestamps (its pages
2154 : * may still be dirty) and isn't currently being allocated or freed.
2155 : * Filesystems should call this if when writing an inode when lazytime is
2156 : * enabled, they want to opportunistically write the timestamps of other inodes
2157 : * located very nearby on-disk, e.g. in the same inode block. This returns true
2158 : * if the given inode is in need of such an opportunistic update. Requires
2159 : * i_lock, or at least later re-checking under i_lock.
2160 : */
2161 : static inline bool inode_is_dirtytime_only(struct inode *inode)
2162 : {
2163 : return (inode->i_state & (I_DIRTY_TIME | I_NEW |
2164 : I_FREEING | I_WILL_FREE)) == I_DIRTY_TIME;
2165 : }
2166 :
2167 : extern void inc_nlink(struct inode *inode);
2168 : extern void drop_nlink(struct inode *inode);
2169 : extern void clear_nlink(struct inode *inode);
2170 : extern void set_nlink(struct inode *inode, unsigned int nlink);
2171 :
2172 : static inline void inode_inc_link_count(struct inode *inode)
2173 : {
2174 : inc_nlink(inode);
2175 : mark_inode_dirty(inode);
2176 : }
2177 :
2178 : static inline void inode_dec_link_count(struct inode *inode)
2179 : {
2180 0 : drop_nlink(inode);
2181 0 : mark_inode_dirty(inode);
2182 : }
2183 :
2184 : enum file_time_flags {
2185 : S_ATIME = 1,
2186 : S_MTIME = 2,
2187 : S_CTIME = 4,
2188 : S_VERSION = 8,
2189 : };
2190 :
2191 : extern bool atime_needs_update(const struct path *, struct inode *);
2192 : extern void touch_atime(const struct path *);
2193 : int inode_update_time(struct inode *inode, struct timespec64 *time, int flags);
2194 :
2195 : static inline void file_accessed(struct file *file)
2196 : {
2197 0 : if (!(file->f_flags & O_NOATIME))
2198 0 : touch_atime(&file->f_path);
2199 : }
2200 :
2201 : extern int file_modified(struct file *file);
2202 : int kiocb_modified(struct kiocb *iocb);
2203 :
2204 : int sync_inode_metadata(struct inode *inode, int wait);
2205 :
2206 : struct file_system_type {
2207 : const char *name;
2208 : int fs_flags;
2209 : #define FS_REQUIRES_DEV 1
2210 : #define FS_BINARY_MOUNTDATA 2
2211 : #define FS_HAS_SUBTYPE 4
2212 : #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2213 : #define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
2214 : #define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
2215 : #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2216 : int (*init_fs_context)(struct fs_context *);
2217 : const struct fs_parameter_spec *parameters;
2218 : struct dentry *(*mount) (struct file_system_type *, int,
2219 : const char *, void *);
2220 : void (*kill_sb) (struct super_block *);
2221 : struct module *owner;
2222 : struct file_system_type * next;
2223 : struct hlist_head fs_supers;
2224 :
2225 : struct lock_class_key s_lock_key;
2226 : struct lock_class_key s_umount_key;
2227 : struct lock_class_key s_vfs_rename_key;
2228 : struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
2229 :
2230 : struct lock_class_key i_lock_key;
2231 : struct lock_class_key i_mutex_key;
2232 : struct lock_class_key invalidate_lock_key;
2233 : struct lock_class_key i_mutex_dir_key;
2234 : };
2235 :
2236 : #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2237 :
2238 : extern struct dentry *mount_bdev(struct file_system_type *fs_type,
2239 : int flags, const char *dev_name, void *data,
2240 : int (*fill_super)(struct super_block *, void *, int));
2241 : extern struct dentry *mount_single(struct file_system_type *fs_type,
2242 : int flags, void *data,
2243 : int (*fill_super)(struct super_block *, void *, int));
2244 : extern struct dentry *mount_nodev(struct file_system_type *fs_type,
2245 : int flags, void *data,
2246 : int (*fill_super)(struct super_block *, void *, int));
2247 : extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
2248 : void retire_super(struct super_block *sb);
2249 : void generic_shutdown_super(struct super_block *sb);
2250 : void kill_block_super(struct super_block *sb);
2251 : void kill_anon_super(struct super_block *sb);
2252 : void kill_litter_super(struct super_block *sb);
2253 : void deactivate_super(struct super_block *sb);
2254 : void deactivate_locked_super(struct super_block *sb);
2255 : int set_anon_super(struct super_block *s, void *data);
2256 : int set_anon_super_fc(struct super_block *s, struct fs_context *fc);
2257 : int get_anon_bdev(dev_t *);
2258 : void free_anon_bdev(dev_t);
2259 : struct super_block *sget_fc(struct fs_context *fc,
2260 : int (*test)(struct super_block *, struct fs_context *),
2261 : int (*set)(struct super_block *, struct fs_context *));
2262 : struct super_block *sget(struct file_system_type *type,
2263 : int (*test)(struct super_block *,void *),
2264 : int (*set)(struct super_block *,void *),
2265 : int flags, void *data);
2266 :
2267 : /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2268 : #define fops_get(fops) \
2269 : (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2270 : #define fops_put(fops) \
2271 : do { if (fops) module_put((fops)->owner); } while(0)
2272 : /*
2273 : * This one is to be used *ONLY* from ->open() instances.
2274 : * fops must be non-NULL, pinned down *and* module dependencies
2275 : * should be sufficient to pin the caller down as well.
2276 : */
2277 : #define replace_fops(f, fops) \
2278 : do { \
2279 : struct file *__file = (f); \
2280 : fops_put(__file->f_op); \
2281 : BUG_ON(!(__file->f_op = (fops))); \
2282 : } while(0)
2283 :
2284 : extern int register_filesystem(struct file_system_type *);
2285 : extern int unregister_filesystem(struct file_system_type *);
2286 : extern int vfs_statfs(const struct path *, struct kstatfs *);
2287 : extern int user_statfs(const char __user *, struct kstatfs *);
2288 : extern int fd_statfs(int, struct kstatfs *);
2289 : extern int freeze_super(struct super_block *super);
2290 : extern int thaw_super(struct super_block *super);
2291 : extern __printf(2, 3)
2292 : int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
2293 : extern int super_setup_bdi(struct super_block *sb);
2294 :
2295 : extern int current_umask(void);
2296 :
2297 : extern void ihold(struct inode * inode);
2298 : extern void iput(struct inode *);
2299 : extern int generic_update_time(struct inode *, struct timespec64 *, int);
2300 :
2301 : /* /sys/fs */
2302 : extern struct kobject *fs_kobj;
2303 :
2304 : #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2305 :
2306 : /* fs/open.c */
2307 : struct audit_names;
2308 : struct filename {
2309 : const char *name; /* pointer to actual string */
2310 : const __user char *uptr; /* original userland pointer */
2311 : int refcnt;
2312 : struct audit_names *aname;
2313 : const char iname[];
2314 : };
2315 : static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
2316 :
2317 : static inline struct mnt_idmap *file_mnt_idmap(struct file *file)
2318 : {
2319 0 : return mnt_idmap(file->f_path.mnt);
2320 : }
2321 :
2322 : /**
2323 : * is_idmapped_mnt - check whether a mount is mapped
2324 : * @mnt: the mount to check
2325 : *
2326 : * If @mnt has an non @nop_mnt_idmap attached to it then @mnt is mapped.
2327 : *
2328 : * Return: true if mount is mapped, false if not.
2329 : */
2330 : static inline bool is_idmapped_mnt(const struct vfsmount *mnt)
2331 : {
2332 0 : return mnt_idmap(mnt) != &nop_mnt_idmap;
2333 : }
2334 :
2335 : extern long vfs_truncate(const struct path *, loff_t);
2336 : int do_truncate(struct mnt_idmap *, struct dentry *, loff_t start,
2337 : unsigned int time_attrs, struct file *filp);
2338 : extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2339 : loff_t len);
2340 : extern long do_sys_open(int dfd, const char __user *filename, int flags,
2341 : umode_t mode);
2342 : extern struct file *file_open_name(struct filename *, int, umode_t);
2343 : extern struct file *filp_open(const char *, int, umode_t);
2344 : extern struct file *file_open_root(const struct path *,
2345 : const char *, int, umode_t);
2346 : static inline struct file *file_open_root_mnt(struct vfsmount *mnt,
2347 : const char *name, int flags, umode_t mode)
2348 : {
2349 0 : return file_open_root(&(struct path){.mnt = mnt, .dentry = mnt->mnt_root},
2350 : name, flags, mode);
2351 : }
2352 : extern struct file * dentry_open(const struct path *, int, const struct cred *);
2353 : extern struct file *dentry_create(const struct path *path, int flags,
2354 : umode_t mode, const struct cred *cred);
2355 : extern struct file * open_with_fake_path(const struct path *, int,
2356 : struct inode*, const struct cred *);
2357 : static inline struct file *file_clone_open(struct file *file)
2358 : {
2359 0 : return dentry_open(&file->f_path, file->f_flags, file->f_cred);
2360 : }
2361 : extern int filp_close(struct file *, fl_owner_t id);
2362 :
2363 : extern struct filename *getname_flags(const char __user *, int, int *);
2364 : extern struct filename *getname_uflags(const char __user *, int);
2365 : extern struct filename *getname(const char __user *);
2366 : extern struct filename *getname_kernel(const char *);
2367 : extern void putname(struct filename *name);
2368 :
2369 : extern int finish_open(struct file *file, struct dentry *dentry,
2370 : int (*open)(struct inode *, struct file *));
2371 : extern int finish_no_open(struct file *file, struct dentry *dentry);
2372 :
2373 : /* Helper for the simple case when original dentry is used */
2374 : static inline int finish_open_simple(struct file *file, int error)
2375 : {
2376 : if (error)
2377 : return error;
2378 :
2379 0 : return finish_open(file, file->f_path.dentry, NULL);
2380 : }
2381 :
2382 : /* fs/dcache.c */
2383 : extern void __init vfs_caches_init_early(void);
2384 : extern void __init vfs_caches_init(void);
2385 :
2386 : extern struct kmem_cache *names_cachep;
2387 :
2388 : #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2389 : #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2390 :
2391 : extern struct super_block *blockdev_superblock;
2392 : static inline bool sb_is_blkdev_sb(struct super_block *sb)
2393 : {
2394 0 : return IS_ENABLED(CONFIG_BLOCK) && sb == blockdev_superblock;
2395 : }
2396 :
2397 : void emergency_thaw_all(void);
2398 : extern int sync_filesystem(struct super_block *);
2399 : extern const struct file_operations def_blk_fops;
2400 : extern const struct file_operations def_chr_fops;
2401 :
2402 : /* fs/char_dev.c */
2403 : #define CHRDEV_MAJOR_MAX 512
2404 : /* Marks the bottom of the first segment of free char majors */
2405 : #define CHRDEV_MAJOR_DYN_END 234
2406 : /* Marks the top and bottom of the second segment of free char majors */
2407 : #define CHRDEV_MAJOR_DYN_EXT_START 511
2408 : #define CHRDEV_MAJOR_DYN_EXT_END 384
2409 :
2410 : extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2411 : extern int register_chrdev_region(dev_t, unsigned, const char *);
2412 : extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2413 : unsigned int count, const char *name,
2414 : const struct file_operations *fops);
2415 : extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2416 : unsigned int count, const char *name);
2417 : extern void unregister_chrdev_region(dev_t, unsigned);
2418 : extern void chrdev_show(struct seq_file *,off_t);
2419 :
2420 : static inline int register_chrdev(unsigned int major, const char *name,
2421 : const struct file_operations *fops)
2422 : {
2423 3 : return __register_chrdev(major, 0, 256, name, fops);
2424 : }
2425 :
2426 : static inline void unregister_chrdev(unsigned int major, const char *name)
2427 : {
2428 0 : __unregister_chrdev(major, 0, 256, name);
2429 : }
2430 :
2431 : extern void init_special_inode(struct inode *, umode_t, dev_t);
2432 :
2433 : /* Invalid inode operations -- fs/bad_inode.c */
2434 : extern void make_bad_inode(struct inode *);
2435 : extern bool is_bad_inode(struct inode *);
2436 :
2437 : extern int __must_check file_fdatawait_range(struct file *file, loff_t lstart,
2438 : loff_t lend);
2439 : extern int __must_check file_check_and_advance_wb_err(struct file *file);
2440 : extern int __must_check file_write_and_wait_range(struct file *file,
2441 : loff_t start, loff_t end);
2442 :
2443 : static inline int file_write_and_wait(struct file *file)
2444 : {
2445 : return file_write_and_wait_range(file, 0, LLONG_MAX);
2446 : }
2447 :
2448 : extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2449 : int datasync);
2450 : extern int vfs_fsync(struct file *file, int datasync);
2451 :
2452 : extern int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
2453 : unsigned int flags);
2454 :
2455 : static inline bool iocb_is_dsync(const struct kiocb *iocb)
2456 : {
2457 0 : return (iocb->ki_flags & IOCB_DSYNC) ||
2458 0 : IS_SYNC(iocb->ki_filp->f_mapping->host);
2459 : }
2460 :
2461 : /*
2462 : * Sync the bytes written if this was a synchronous write. Expect ki_pos
2463 : * to already be updated for the write, and will return either the amount
2464 : * of bytes passed in, or an error if syncing the file failed.
2465 : */
2466 0 : static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
2467 : {
2468 0 : if (iocb_is_dsync(iocb)) {
2469 0 : int ret = vfs_fsync_range(iocb->ki_filp,
2470 0 : iocb->ki_pos - count, iocb->ki_pos - 1,
2471 0 : (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
2472 0 : if (ret)
2473 0 : return ret;
2474 : }
2475 :
2476 : return count;
2477 : }
2478 :
2479 : extern void emergency_sync(void);
2480 : extern void emergency_remount(void);
2481 :
2482 : #ifdef CONFIG_BLOCK
2483 : extern int bmap(struct inode *inode, sector_t *block);
2484 : #else
2485 : static inline int bmap(struct inode *inode, sector_t *block)
2486 : {
2487 : return -EINVAL;
2488 : }
2489 : #endif
2490 :
2491 : int notify_change(struct mnt_idmap *, struct dentry *,
2492 : struct iattr *, struct inode **);
2493 : int inode_permission(struct mnt_idmap *, struct inode *, int);
2494 : int generic_permission(struct mnt_idmap *, struct inode *, int);
2495 : static inline int file_permission(struct file *file, int mask)
2496 : {
2497 0 : return inode_permission(file_mnt_idmap(file),
2498 : file_inode(file), mask);
2499 : }
2500 : static inline int path_permission(const struct path *path, int mask)
2501 : {
2502 0 : return inode_permission(mnt_idmap(path->mnt),
2503 0 : d_inode(path->dentry), mask);
2504 : }
2505 : int __check_sticky(struct mnt_idmap *idmap, struct inode *dir,
2506 : struct inode *inode);
2507 :
2508 : static inline bool execute_ok(struct inode *inode)
2509 : {
2510 : return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2511 : }
2512 :
2513 : static inline bool inode_wrong_type(const struct inode *inode, umode_t mode)
2514 : {
2515 : return (inode->i_mode ^ mode) & S_IFMT;
2516 : }
2517 :
2518 : static inline void file_start_write(struct file *file)
2519 : {
2520 0 : if (!S_ISREG(file_inode(file)->i_mode))
2521 : return;
2522 0 : sb_start_write(file_inode(file)->i_sb);
2523 : }
2524 :
2525 : static inline bool file_start_write_trylock(struct file *file)
2526 : {
2527 : if (!S_ISREG(file_inode(file)->i_mode))
2528 : return true;
2529 : return sb_start_write_trylock(file_inode(file)->i_sb);
2530 : }
2531 :
2532 : static inline void file_end_write(struct file *file)
2533 : {
2534 0 : if (!S_ISREG(file_inode(file)->i_mode))
2535 : return;
2536 0 : __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2537 : }
2538 :
2539 : /*
2540 : * This is used for regular files where some users -- especially the
2541 : * currently executed binary in a process, previously handled via
2542 : * VM_DENYWRITE -- cannot handle concurrent write (and maybe mmap
2543 : * read-write shared) accesses.
2544 : *
2545 : * get_write_access() gets write permission for a file.
2546 : * put_write_access() releases this write permission.
2547 : * deny_write_access() denies write access to a file.
2548 : * allow_write_access() re-enables write access to a file.
2549 : *
2550 : * The i_writecount field of an inode can have the following values:
2551 : * 0: no write access, no denied write access
2552 : * < 0: (-i_writecount) users that denied write access to the file.
2553 : * > 0: (i_writecount) users that have write access to the file.
2554 : *
2555 : * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2556 : * except for the cases where we don't hold i_writecount yet. Then we need to
2557 : * use {get,deny}_write_access() - these functions check the sign and refuse
2558 : * to do the change if sign is wrong.
2559 : */
2560 : static inline int get_write_access(struct inode *inode)
2561 : {
2562 0 : return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2563 : }
2564 : static inline int deny_write_access(struct file *file)
2565 : {
2566 0 : struct inode *inode = file_inode(file);
2567 0 : return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2568 : }
2569 : static inline void put_write_access(struct inode * inode)
2570 : {
2571 0 : atomic_dec(&inode->i_writecount);
2572 : }
2573 : static inline void allow_write_access(struct file *file)
2574 : {
2575 0 : if (file)
2576 0 : atomic_inc(&file_inode(file)->i_writecount);
2577 : }
2578 : static inline bool inode_is_open_for_write(const struct inode *inode)
2579 : {
2580 0 : return atomic_read(&inode->i_writecount) > 0;
2581 : }
2582 :
2583 : #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
2584 0 : static inline void i_readcount_dec(struct inode *inode)
2585 : {
2586 0 : BUG_ON(!atomic_read(&inode->i_readcount));
2587 0 : atomic_dec(&inode->i_readcount);
2588 0 : }
2589 : static inline void i_readcount_inc(struct inode *inode)
2590 : {
2591 0 : atomic_inc(&inode->i_readcount);
2592 : }
2593 : #else
2594 : static inline void i_readcount_dec(struct inode *inode)
2595 : {
2596 : return;
2597 : }
2598 : static inline void i_readcount_inc(struct inode *inode)
2599 : {
2600 : return;
2601 : }
2602 : #endif
2603 : extern int do_pipe_flags(int *, int);
2604 :
2605 : extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
2606 : ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos);
2607 : extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *);
2608 : extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *);
2609 : extern struct file * open_exec(const char *);
2610 :
2611 : /* fs/dcache.c -- generic fs support functions */
2612 : extern bool is_subdir(struct dentry *, struct dentry *);
2613 : extern bool path_is_under(const struct path *, const struct path *);
2614 :
2615 : extern char *file_path(struct file *, char *, int);
2616 :
2617 : #include <linux/err.h>
2618 :
2619 : /* needed for stackable file system support */
2620 : extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2621 :
2622 : extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2623 :
2624 : extern int inode_init_always(struct super_block *, struct inode *);
2625 : extern void inode_init_once(struct inode *);
2626 : extern void address_space_init_once(struct address_space *mapping);
2627 : extern struct inode * igrab(struct inode *);
2628 : extern ino_t iunique(struct super_block *, ino_t);
2629 : extern int inode_needs_sync(struct inode *inode);
2630 : extern int generic_delete_inode(struct inode *inode);
2631 : static inline int generic_drop_inode(struct inode *inode)
2632 : {
2633 88 : return !inode->i_nlink || inode_unhashed(inode);
2634 : }
2635 : extern void d_mark_dontcache(struct inode *inode);
2636 :
2637 : extern struct inode *ilookup5_nowait(struct super_block *sb,
2638 : unsigned long hashval, int (*test)(struct inode *, void *),
2639 : void *data);
2640 : extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2641 : int (*test)(struct inode *, void *), void *data);
2642 : extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2643 :
2644 : extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
2645 : int (*test)(struct inode *, void *),
2646 : int (*set)(struct inode *, void *),
2647 : void *data);
2648 : extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2649 : extern struct inode * iget_locked(struct super_block *, unsigned long);
2650 : extern struct inode *find_inode_nowait(struct super_block *,
2651 : unsigned long,
2652 : int (*match)(struct inode *,
2653 : unsigned long, void *),
2654 : void *data);
2655 : extern struct inode *find_inode_rcu(struct super_block *, unsigned long,
2656 : int (*)(struct inode *, void *), void *);
2657 : extern struct inode *find_inode_by_ino_rcu(struct super_block *, unsigned long);
2658 : extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2659 : extern int insert_inode_locked(struct inode *);
2660 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
2661 : extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2662 : #else
2663 : static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2664 : #endif
2665 : extern void unlock_new_inode(struct inode *);
2666 : extern void discard_new_inode(struct inode *);
2667 : extern unsigned int get_next_ino(void);
2668 : extern void evict_inodes(struct super_block *sb);
2669 : void dump_mapping(const struct address_space *);
2670 :
2671 : /*
2672 : * Userspace may rely on the the inode number being non-zero. For example, glibc
2673 : * simply ignores files with zero i_ino in unlink() and other places.
2674 : *
2675 : * As an additional complication, if userspace was compiled with
2676 : * _FILE_OFFSET_BITS=32 on a 64-bit kernel we'll only end up reading out the
2677 : * lower 32 bits, so we need to check that those aren't zero explicitly. With
2678 : * _FILE_OFFSET_BITS=64, this may cause some harmless false-negatives, but
2679 : * better safe than sorry.
2680 : */
2681 : static inline bool is_zero_ino(ino_t ino)
2682 : {
2683 1 : return (u32)ino == 0;
2684 : }
2685 :
2686 : extern void __iget(struct inode * inode);
2687 : extern void iget_failed(struct inode *);
2688 : extern void clear_inode(struct inode *);
2689 : extern void __destroy_inode(struct inode *);
2690 : extern struct inode *new_inode_pseudo(struct super_block *sb);
2691 : extern struct inode *new_inode(struct super_block *sb);
2692 : extern void free_inode_nonrcu(struct inode *inode);
2693 : extern int setattr_should_drop_suidgid(struct mnt_idmap *, struct inode *);
2694 : extern int file_remove_privs(struct file *);
2695 : int setattr_should_drop_sgid(struct mnt_idmap *idmap,
2696 : const struct inode *inode);
2697 :
2698 : /*
2699 : * This must be used for allocating filesystems specific inodes to set
2700 : * up the inode reclaim context correctly.
2701 : */
2702 : static inline void *
2703 : alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp)
2704 : {
2705 61 : return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp);
2706 : }
2707 :
2708 : extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2709 : static inline void insert_inode_hash(struct inode *inode)
2710 : {
2711 0 : __insert_inode_hash(inode, inode->i_ino);
2712 : }
2713 :
2714 : extern void __remove_inode_hash(struct inode *);
2715 : static inline void remove_inode_hash(struct inode *inode)
2716 : {
2717 44 : if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
2718 0 : __remove_inode_hash(inode);
2719 : }
2720 :
2721 : extern void inode_sb_list_add(struct inode *inode);
2722 : extern void inode_add_lru(struct inode *inode);
2723 :
2724 : extern int sb_set_blocksize(struct super_block *, int);
2725 : extern int sb_min_blocksize(struct super_block *, int);
2726 :
2727 : extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2728 : extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2729 : extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
2730 : int generic_write_checks_count(struct kiocb *iocb, loff_t *count);
2731 : extern int generic_write_check_limits(struct file *file, loff_t pos,
2732 : loff_t *count);
2733 : extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);
2734 : ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *to,
2735 : ssize_t already_read);
2736 : extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2737 : extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
2738 : extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
2739 : extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
2740 : ssize_t generic_perform_write(struct kiocb *, struct iov_iter *);
2741 :
2742 : ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
2743 : rwf_t flags);
2744 : ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
2745 : rwf_t flags);
2746 : ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb,
2747 : struct iov_iter *iter);
2748 : ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb,
2749 : struct iov_iter *iter);
2750 :
2751 : /* fs/splice.c */
2752 : ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
2753 : struct pipe_inode_info *pipe,
2754 : size_t len, unsigned int flags);
2755 : ssize_t direct_splice_read(struct file *in, loff_t *ppos,
2756 : struct pipe_inode_info *pipe,
2757 : size_t len, unsigned int flags);
2758 : extern ssize_t generic_file_splice_read(struct file *, loff_t *,
2759 : struct pipe_inode_info *, size_t, unsigned int);
2760 : extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
2761 : struct file *, loff_t *, size_t, unsigned int);
2762 : extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2763 : struct file *out, loff_t *, size_t len, unsigned int flags);
2764 : extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
2765 : loff_t *opos, size_t len, unsigned int flags);
2766 :
2767 :
2768 : extern void
2769 : file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2770 : extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
2771 : #define no_llseek NULL
2772 : extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
2773 : extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
2774 : extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
2775 : int whence, loff_t maxsize, loff_t eof);
2776 : extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
2777 : int whence, loff_t size);
2778 : extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
2779 : extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
2780 : int rw_verify_area(int, struct file *, const loff_t *, size_t);
2781 : extern int generic_file_open(struct inode * inode, struct file * filp);
2782 : extern int nonseekable_open(struct inode * inode, struct file * filp);
2783 : extern int stream_open(struct inode * inode, struct file * filp);
2784 :
2785 : #ifdef CONFIG_BLOCK
2786 : typedef void (dio_submit_t)(struct bio *bio, struct inode *inode,
2787 : loff_t file_offset);
2788 :
2789 : enum {
2790 : /* need locking between buffered and direct access */
2791 : DIO_LOCKING = 0x01,
2792 :
2793 : /* filesystem does not support filling holes */
2794 : DIO_SKIP_HOLES = 0x02,
2795 : };
2796 :
2797 : ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
2798 : struct block_device *bdev, struct iov_iter *iter,
2799 : get_block_t get_block,
2800 : dio_iodone_t end_io,
2801 : int flags);
2802 :
2803 : static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
2804 : struct inode *inode,
2805 : struct iov_iter *iter,
2806 : get_block_t get_block)
2807 : {
2808 : return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
2809 : get_block, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
2810 : }
2811 : #endif
2812 :
2813 : void inode_dio_wait(struct inode *inode);
2814 :
2815 : /**
2816 : * inode_dio_begin - signal start of a direct I/O requests
2817 : * @inode: inode the direct I/O happens on
2818 : *
2819 : * This is called once we've finished processing a direct I/O request,
2820 : * and is used to wake up callers waiting for direct I/O to be quiesced.
2821 : */
2822 : static inline void inode_dio_begin(struct inode *inode)
2823 : {
2824 : atomic_inc(&inode->i_dio_count);
2825 : }
2826 :
2827 : /**
2828 : * inode_dio_end - signal finish of a direct I/O requests
2829 : * @inode: inode the direct I/O happens on
2830 : *
2831 : * This is called once we've finished processing a direct I/O request,
2832 : * and is used to wake up callers waiting for direct I/O to be quiesced.
2833 : */
2834 : static inline void inode_dio_end(struct inode *inode)
2835 : {
2836 : if (atomic_dec_and_test(&inode->i_dio_count))
2837 : wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
2838 : }
2839 :
2840 : /*
2841 : * Warn about a page cache invalidation failure diring a direct I/O write.
2842 : */
2843 : void dio_warn_stale_pagecache(struct file *filp);
2844 :
2845 : extern void inode_set_flags(struct inode *inode, unsigned int flags,
2846 : unsigned int mask);
2847 :
2848 : extern const struct file_operations generic_ro_fops;
2849 :
2850 : #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2851 :
2852 : extern int readlink_copy(char __user *, int, const char *);
2853 : extern int page_readlink(struct dentry *, char __user *, int);
2854 : extern const char *page_get_link(struct dentry *, struct inode *,
2855 : struct delayed_call *);
2856 : extern void page_put_link(void *);
2857 : extern int page_symlink(struct inode *inode, const char *symname, int len);
2858 : extern const struct inode_operations page_symlink_inode_operations;
2859 : extern void kfree_link(void *);
2860 : void generic_fillattr(struct mnt_idmap *, struct inode *, struct kstat *);
2861 : void generic_fill_statx_attr(struct inode *inode, struct kstat *stat);
2862 : extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
2863 : extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
2864 : void __inode_add_bytes(struct inode *inode, loff_t bytes);
2865 : void inode_add_bytes(struct inode *inode, loff_t bytes);
2866 : void __inode_sub_bytes(struct inode *inode, loff_t bytes);
2867 : void inode_sub_bytes(struct inode *inode, loff_t bytes);
2868 : static inline loff_t __inode_get_bytes(struct inode *inode)
2869 : {
2870 0 : return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
2871 : }
2872 : loff_t inode_get_bytes(struct inode *inode);
2873 : void inode_set_bytes(struct inode *inode, loff_t bytes);
2874 : const char *simple_get_link(struct dentry *, struct inode *,
2875 : struct delayed_call *);
2876 : extern const struct inode_operations simple_symlink_inode_operations;
2877 :
2878 : extern int iterate_dir(struct file *, struct dir_context *);
2879 :
2880 : int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
2881 : int flags);
2882 : int vfs_fstat(int fd, struct kstat *stat);
2883 :
2884 : static inline int vfs_stat(const char __user *filename, struct kstat *stat)
2885 : {
2886 0 : return vfs_fstatat(AT_FDCWD, filename, stat, 0);
2887 : }
2888 : static inline int vfs_lstat(const char __user *name, struct kstat *stat)
2889 : {
2890 0 : return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
2891 : }
2892 :
2893 : extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
2894 : extern int vfs_readlink(struct dentry *, char __user *, int);
2895 :
2896 : extern struct file_system_type *get_filesystem(struct file_system_type *fs);
2897 : extern void put_filesystem(struct file_system_type *fs);
2898 : extern struct file_system_type *get_fs_type(const char *name);
2899 : extern struct super_block *get_super(struct block_device *);
2900 : extern struct super_block *get_active_super(struct block_device *bdev);
2901 : extern void drop_super(struct super_block *sb);
2902 : extern void drop_super_exclusive(struct super_block *sb);
2903 : extern void iterate_supers(void (*)(struct super_block *, void *), void *);
2904 : extern void iterate_supers_type(struct file_system_type *,
2905 : void (*)(struct super_block *, void *), void *);
2906 :
2907 : extern int dcache_dir_open(struct inode *, struct file *);
2908 : extern int dcache_dir_close(struct inode *, struct file *);
2909 : extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2910 : extern int dcache_readdir(struct file *, struct dir_context *);
2911 : extern int simple_setattr(struct mnt_idmap *, struct dentry *,
2912 : struct iattr *);
2913 : extern int simple_getattr(struct mnt_idmap *, const struct path *,
2914 : struct kstat *, u32, unsigned int);
2915 : extern int simple_statfs(struct dentry *, struct kstatfs *);
2916 : extern int simple_open(struct inode *inode, struct file *file);
2917 : extern int simple_link(struct dentry *, struct inode *, struct dentry *);
2918 : extern int simple_unlink(struct inode *, struct dentry *);
2919 : extern int simple_rmdir(struct inode *, struct dentry *);
2920 : extern int simple_rename_exchange(struct inode *old_dir, struct dentry *old_dentry,
2921 : struct inode *new_dir, struct dentry *new_dentry);
2922 : extern int simple_rename(struct mnt_idmap *, struct inode *,
2923 : struct dentry *, struct inode *, struct dentry *,
2924 : unsigned int);
2925 : extern void simple_recursive_removal(struct dentry *,
2926 : void (*callback)(struct dentry *));
2927 : extern int noop_fsync(struct file *, loff_t, loff_t, int);
2928 : extern ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
2929 : extern int simple_empty(struct dentry *);
2930 : extern int simple_write_begin(struct file *file, struct address_space *mapping,
2931 : loff_t pos, unsigned len,
2932 : struct page **pagep, void **fsdata);
2933 : extern const struct address_space_operations ram_aops;
2934 : extern int always_delete_dentry(const struct dentry *);
2935 : extern struct inode *alloc_anon_inode(struct super_block *);
2936 : extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
2937 : extern const struct dentry_operations simple_dentry_operations;
2938 :
2939 : extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
2940 : extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2941 : extern const struct file_operations simple_dir_operations;
2942 : extern const struct inode_operations simple_dir_inode_operations;
2943 : extern void make_empty_dir_inode(struct inode *inode);
2944 : extern bool is_empty_dir_inode(struct inode *inode);
2945 : struct tree_descr { const char *name; const struct file_operations *ops; int mode; };
2946 : struct dentry *d_alloc_name(struct dentry *, const char *);
2947 : extern int simple_fill_super(struct super_block *, unsigned long,
2948 : const struct tree_descr *);
2949 : extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2950 : extern void simple_release_fs(struct vfsmount **mount, int *count);
2951 :
2952 : extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2953 : loff_t *ppos, const void *from, size_t available);
2954 : extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
2955 : const void __user *from, size_t count);
2956 :
2957 : extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
2958 : extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
2959 :
2960 : extern int generic_check_addressable(unsigned, u64);
2961 :
2962 : extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
2963 :
2964 : int may_setattr(struct mnt_idmap *idmap, struct inode *inode,
2965 : unsigned int ia_valid);
2966 : int setattr_prepare(struct mnt_idmap *, struct dentry *, struct iattr *);
2967 : extern int inode_newsize_ok(const struct inode *, loff_t offset);
2968 : void setattr_copy(struct mnt_idmap *, struct inode *inode,
2969 : const struct iattr *attr);
2970 :
2971 : extern int file_update_time(struct file *file);
2972 :
2973 : static inline bool vma_is_dax(const struct vm_area_struct *vma)
2974 : {
2975 : return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
2976 : }
2977 :
2978 : static inline bool vma_is_fsdax(struct vm_area_struct *vma)
2979 : {
2980 : struct inode *inode;
2981 :
2982 : if (!IS_ENABLED(CONFIG_FS_DAX) || !vma->vm_file)
2983 : return false;
2984 : if (!vma_is_dax(vma))
2985 : return false;
2986 : inode = file_inode(vma->vm_file);
2987 : if (S_ISCHR(inode->i_mode))
2988 : return false; /* device-dax */
2989 : return true;
2990 : }
2991 :
2992 : static inline int iocb_flags(struct file *file)
2993 : {
2994 0 : int res = 0;
2995 0 : if (file->f_flags & O_APPEND)
2996 0 : res |= IOCB_APPEND;
2997 0 : if (file->f_flags & O_DIRECT)
2998 0 : res |= IOCB_DIRECT;
2999 0 : if (file->f_flags & O_DSYNC)
3000 0 : res |= IOCB_DSYNC;
3001 0 : if (file->f_flags & __O_SYNC)
3002 0 : res |= IOCB_SYNC;
3003 : return res;
3004 : }
3005 :
3006 0 : static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
3007 : {
3008 0 : int kiocb_flags = 0;
3009 :
3010 : /* make sure there's no overlap between RWF and private IOCB flags */
3011 : BUILD_BUG_ON((__force int) RWF_SUPPORTED & IOCB_EVENTFD);
3012 :
3013 0 : if (!flags)
3014 : return 0;
3015 0 : if (unlikely(flags & ~RWF_SUPPORTED))
3016 : return -EOPNOTSUPP;
3017 :
3018 0 : if (flags & RWF_NOWAIT) {
3019 0 : if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
3020 : return -EOPNOTSUPP;
3021 : kiocb_flags |= IOCB_NOIO;
3022 : }
3023 0 : kiocb_flags |= (__force int) (flags & RWF_SUPPORTED);
3024 0 : if (flags & RWF_SYNC)
3025 0 : kiocb_flags |= IOCB_DSYNC;
3026 :
3027 0 : ki->ki_flags |= kiocb_flags;
3028 : return 0;
3029 : }
3030 :
3031 : static inline ino_t parent_ino(struct dentry *dentry)
3032 : {
3033 : ino_t res;
3034 :
3035 : /*
3036 : * Don't strictly need d_lock here? If the parent ino could change
3037 : * then surely we'd have a deeper race in the caller?
3038 : */
3039 0 : spin_lock(&dentry->d_lock);
3040 0 : res = dentry->d_parent->d_inode->i_ino;
3041 0 : spin_unlock(&dentry->d_lock);
3042 : return res;
3043 : }
3044 :
3045 : /* Transaction based IO helpers */
3046 :
3047 : /*
3048 : * An argresp is stored in an allocated page and holds the
3049 : * size of the argument or response, along with its content
3050 : */
3051 : struct simple_transaction_argresp {
3052 : ssize_t size;
3053 : char data[];
3054 : };
3055 :
3056 : #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3057 :
3058 : char *simple_transaction_get(struct file *file, const char __user *buf,
3059 : size_t size);
3060 : ssize_t simple_transaction_read(struct file *file, char __user *buf,
3061 : size_t size, loff_t *pos);
3062 : int simple_transaction_release(struct inode *inode, struct file *file);
3063 :
3064 : void simple_transaction_set(struct file *file, size_t n);
3065 :
3066 : /*
3067 : * simple attribute files
3068 : *
3069 : * These attributes behave similar to those in sysfs:
3070 : *
3071 : * Writing to an attribute immediately sets a value, an open file can be
3072 : * written to multiple times.
3073 : *
3074 : * Reading from an attribute creates a buffer from the value that might get
3075 : * read with multiple read calls. When the attribute has been read
3076 : * completely, no further read calls are possible until the file is opened
3077 : * again.
3078 : *
3079 : * All attributes contain a text representation of a numeric value
3080 : * that are accessed with the get() and set() functions.
3081 : */
3082 : #define DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, __is_signed) \
3083 : static int __fops ## _open(struct inode *inode, struct file *file) \
3084 : { \
3085 : __simple_attr_check_format(__fmt, 0ull); \
3086 : return simple_attr_open(inode, file, __get, __set, __fmt); \
3087 : } \
3088 : static const struct file_operations __fops = { \
3089 : .owner = THIS_MODULE, \
3090 : .open = __fops ## _open, \
3091 : .release = simple_attr_release, \
3092 : .read = simple_attr_read, \
3093 : .write = (__is_signed) ? simple_attr_write_signed : simple_attr_write, \
3094 : .llseek = generic_file_llseek, \
3095 : }
3096 :
3097 : #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3098 : DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, false)
3099 :
3100 : #define DEFINE_SIMPLE_ATTRIBUTE_SIGNED(__fops, __get, __set, __fmt) \
3101 : DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, true)
3102 :
3103 : static inline __printf(1, 2)
3104 : void __simple_attr_check_format(const char *fmt, ...)
3105 : {
3106 : /* don't do anything, just let the compiler check the arguments; */
3107 : }
3108 :
3109 : int simple_attr_open(struct inode *inode, struct file *file,
3110 : int (*get)(void *, u64 *), int (*set)(void *, u64),
3111 : const char *fmt);
3112 : int simple_attr_release(struct inode *inode, struct file *file);
3113 : ssize_t simple_attr_read(struct file *file, char __user *buf,
3114 : size_t len, loff_t *ppos);
3115 : ssize_t simple_attr_write(struct file *file, const char __user *buf,
3116 : size_t len, loff_t *ppos);
3117 : ssize_t simple_attr_write_signed(struct file *file, const char __user *buf,
3118 : size_t len, loff_t *ppos);
3119 :
3120 : struct ctl_table;
3121 : int __init list_bdev_fs_names(char *buf, size_t size);
3122 :
3123 : #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3124 : #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3125 :
3126 : #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3127 : #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3128 : (flag & __FMODE_NONOTIFY)))
3129 :
3130 : static inline bool is_sxid(umode_t mode)
3131 : {
3132 : return mode & (S_ISUID | S_ISGID);
3133 : }
3134 :
3135 : static inline int check_sticky(struct mnt_idmap *idmap,
3136 : struct inode *dir, struct inode *inode)
3137 : {
3138 0 : if (!(dir->i_mode & S_ISVTX))
3139 : return 0;
3140 :
3141 0 : return __check_sticky(idmap, dir, inode);
3142 : }
3143 :
3144 : static inline void inode_has_no_xattr(struct inode *inode)
3145 : {
3146 0 : if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & SB_NOSEC))
3147 0 : inode->i_flags |= S_NOSEC;
3148 : }
3149 :
3150 : static inline bool is_root_inode(struct inode *inode)
3151 : {
3152 : return inode == inode->i_sb->s_root->d_inode;
3153 : }
3154 :
3155 : static inline bool dir_emit(struct dir_context *ctx,
3156 : const char *name, int namelen,
3157 : u64 ino, unsigned type)
3158 : {
3159 0 : return ctx->actor(ctx, name, namelen, ctx->pos, ino, type);
3160 : }
3161 : static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
3162 : {
3163 0 : return ctx->actor(ctx, ".", 1, ctx->pos,
3164 0 : file->f_path.dentry->d_inode->i_ino, DT_DIR);
3165 : }
3166 : static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
3167 : {
3168 0 : return ctx->actor(ctx, "..", 2, ctx->pos,
3169 0 : parent_ino(file->f_path.dentry), DT_DIR);
3170 : }
3171 0 : static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
3172 : {
3173 0 : if (ctx->pos == 0) {
3174 0 : if (!dir_emit_dot(file, ctx))
3175 : return false;
3176 0 : ctx->pos = 1;
3177 : }
3178 0 : if (ctx->pos == 1) {
3179 0 : if (!dir_emit_dotdot(file, ctx))
3180 : return false;
3181 0 : ctx->pos = 2;
3182 : }
3183 : return true;
3184 : }
3185 : static inline bool dir_relax(struct inode *inode)
3186 : {
3187 : inode_unlock(inode);
3188 : inode_lock(inode);
3189 : return !IS_DEADDIR(inode);
3190 : }
3191 :
3192 : static inline bool dir_relax_shared(struct inode *inode)
3193 : {
3194 : inode_unlock_shared(inode);
3195 : inode_lock_shared(inode);
3196 : return !IS_DEADDIR(inode);
3197 : }
3198 :
3199 : extern bool path_noexec(const struct path *path);
3200 : extern void inode_nohighmem(struct inode *inode);
3201 :
3202 : /* mm/fadvise.c */
3203 : extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len,
3204 : int advice);
3205 : extern int generic_fadvise(struct file *file, loff_t offset, loff_t len,
3206 : int advice);
3207 :
3208 : #endif /* _LINUX_FS_H */
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