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 was opened by fanotify and shouldn't generate fanotify events */
172 : #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
173 :
174 : /* File is capable of returning -EAGAIN if I/O will block */
175 : #define FMODE_NOWAIT ((__force fmode_t)0x8000000)
176 :
177 : /* File represents mount that needs unmounting */
178 : #define FMODE_NEED_UNMOUNT ((__force fmode_t)0x10000000)
179 :
180 : /* File does not contribute to nr_files count */
181 : #define FMODE_NOACCOUNT ((__force fmode_t)0x20000000)
182 :
183 : /* File supports async buffered reads */
184 : #define FMODE_BUF_RASYNC ((__force fmode_t)0x40000000)
185 :
186 : /* File supports async nowait buffered writes */
187 : #define FMODE_BUF_WASYNC ((__force fmode_t)0x80000000)
188 :
189 : /*
190 : * Attribute flags. These should be or-ed together to figure out what
191 : * has been changed!
192 : */
193 : #define ATTR_MODE (1 << 0)
194 : #define ATTR_UID (1 << 1)
195 : #define ATTR_GID (1 << 2)
196 : #define ATTR_SIZE (1 << 3)
197 : #define ATTR_ATIME (1 << 4)
198 : #define ATTR_MTIME (1 << 5)
199 : #define ATTR_CTIME (1 << 6)
200 : #define ATTR_ATIME_SET (1 << 7)
201 : #define ATTR_MTIME_SET (1 << 8)
202 : #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
203 : #define ATTR_KILL_SUID (1 << 11)
204 : #define ATTR_KILL_SGID (1 << 12)
205 : #define ATTR_FILE (1 << 13)
206 : #define ATTR_KILL_PRIV (1 << 14)
207 : #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
208 : #define ATTR_TIMES_SET (1 << 16)
209 : #define ATTR_TOUCH (1 << 17)
210 :
211 : /*
212 : * Whiteout is represented by a char device. The following constants define the
213 : * mode and device number to use.
214 : */
215 : #define WHITEOUT_MODE 0
216 : #define WHITEOUT_DEV 0
217 :
218 : /*
219 : * This is the Inode Attributes structure, used for notify_change(). It
220 : * uses the above definitions as flags, to know which values have changed.
221 : * Also, in this manner, a Filesystem can look at only the values it cares
222 : * about. Basically, these are the attributes that the VFS layer can
223 : * request to change from the FS layer.
224 : *
225 : * Derek Atkins <warlord@MIT.EDU> 94-10-20
226 : */
227 : struct iattr {
228 : unsigned int ia_valid;
229 : umode_t ia_mode;
230 : /*
231 : * The two anonymous unions wrap structures with the same member.
232 : *
233 : * Filesystems raising FS_ALLOW_IDMAP need to use ia_vfs{g,u}id which
234 : * are a dedicated type requiring the filesystem to use the dedicated
235 : * helpers. Other filesystem can continue to use ia_{g,u}id until they
236 : * have been ported.
237 : *
238 : * They always contain the same value. In other words FS_ALLOW_IDMAP
239 : * pass down the same value on idmapped mounts as they would on regular
240 : * mounts.
241 : */
242 : union {
243 : kuid_t ia_uid;
244 : vfsuid_t ia_vfsuid;
245 : };
246 : union {
247 : kgid_t ia_gid;
248 : vfsgid_t ia_vfsgid;
249 : };
250 : loff_t ia_size;
251 : struct timespec64 ia_atime;
252 : struct timespec64 ia_mtime;
253 : struct timespec64 ia_ctime;
254 :
255 : /*
256 : * Not an attribute, but an auxiliary info for filesystems wanting to
257 : * implement an ftruncate() like method. NOTE: filesystem should
258 : * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
259 : */
260 : struct file *ia_file;
261 : };
262 :
263 : /*
264 : * Includes for diskquotas.
265 : */
266 : #include <linux/quota.h>
267 :
268 : /*
269 : * Maximum number of layers of fs stack. Needs to be limited to
270 : * prevent kernel stack overflow
271 : */
272 : #define FILESYSTEM_MAX_STACK_DEPTH 2
273 :
274 : /**
275 : * enum positive_aop_returns - aop return codes with specific semantics
276 : *
277 : * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
278 : * completed, that the page is still locked, and
279 : * should be considered active. The VM uses this hint
280 : * to return the page to the active list -- it won't
281 : * be a candidate for writeback again in the near
282 : * future. Other callers must be careful to unlock
283 : * the page if they get this return. Returned by
284 : * writepage();
285 : *
286 : * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
287 : * unlocked it and the page might have been truncated.
288 : * The caller should back up to acquiring a new page and
289 : * trying again. The aop will be taking reasonable
290 : * precautions not to livelock. If the caller held a page
291 : * reference, it should drop it before retrying. Returned
292 : * by read_folio().
293 : *
294 : * address_space_operation functions return these large constants to indicate
295 : * special semantics to the caller. These are much larger than the bytes in a
296 : * page to allow for functions that return the number of bytes operated on in a
297 : * given page.
298 : */
299 :
300 : enum positive_aop_returns {
301 : AOP_WRITEPAGE_ACTIVATE = 0x80000,
302 : AOP_TRUNCATED_PAGE = 0x80001,
303 : };
304 :
305 : /*
306 : * oh the beauties of C type declarations.
307 : */
308 : struct page;
309 : struct address_space;
310 : struct writeback_control;
311 : struct readahead_control;
312 :
313 : /*
314 : * Write life time hint values.
315 : * Stored in struct inode as u8.
316 : */
317 : enum rw_hint {
318 : WRITE_LIFE_NOT_SET = 0,
319 : WRITE_LIFE_NONE = RWH_WRITE_LIFE_NONE,
320 : WRITE_LIFE_SHORT = RWH_WRITE_LIFE_SHORT,
321 : WRITE_LIFE_MEDIUM = RWH_WRITE_LIFE_MEDIUM,
322 : WRITE_LIFE_LONG = RWH_WRITE_LIFE_LONG,
323 : WRITE_LIFE_EXTREME = RWH_WRITE_LIFE_EXTREME,
324 : };
325 :
326 : /* Match RWF_* bits to IOCB bits */
327 : #define IOCB_HIPRI (__force int) RWF_HIPRI
328 : #define IOCB_DSYNC (__force int) RWF_DSYNC
329 : #define IOCB_SYNC (__force int) RWF_SYNC
330 : #define IOCB_NOWAIT (__force int) RWF_NOWAIT
331 : #define IOCB_APPEND (__force int) RWF_APPEND
332 :
333 : /* non-RWF related bits - start at 16 */
334 : #define IOCB_EVENTFD (1 << 16)
335 : #define IOCB_DIRECT (1 << 17)
336 : #define IOCB_WRITE (1 << 18)
337 : /* iocb->ki_waitq is valid */
338 : #define IOCB_WAITQ (1 << 19)
339 : #define IOCB_NOIO (1 << 20)
340 : /* can use bio alloc cache */
341 : #define IOCB_ALLOC_CACHE (1 << 21)
342 :
343 : struct kiocb {
344 : struct file *ki_filp;
345 : loff_t ki_pos;
346 : void (*ki_complete)(struct kiocb *iocb, long ret);
347 : void *private;
348 : int ki_flags;
349 : u16 ki_ioprio; /* See linux/ioprio.h */
350 : struct wait_page_queue *ki_waitq; /* for async buffered IO */
351 : };
352 :
353 : static inline bool is_sync_kiocb(struct kiocb *kiocb)
354 : {
355 : return kiocb->ki_complete == NULL;
356 : }
357 :
358 : struct address_space_operations {
359 : int (*writepage)(struct page *page, struct writeback_control *wbc);
360 : int (*read_folio)(struct file *, struct folio *);
361 :
362 : /* Write back some dirty pages from this mapping. */
363 : int (*writepages)(struct address_space *, struct writeback_control *);
364 :
365 : /* Mark a folio dirty. Return true if this dirtied it */
366 : bool (*dirty_folio)(struct address_space *, struct folio *);
367 :
368 : void (*readahead)(struct readahead_control *);
369 :
370 : int (*write_begin)(struct file *, struct address_space *mapping,
371 : loff_t pos, unsigned len,
372 : struct page **pagep, void **fsdata);
373 : int (*write_end)(struct file *, struct address_space *mapping,
374 : loff_t pos, unsigned len, unsigned copied,
375 : struct page *page, void *fsdata);
376 :
377 : /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
378 : sector_t (*bmap)(struct address_space *, sector_t);
379 : void (*invalidate_folio) (struct folio *, size_t offset, size_t len);
380 : bool (*release_folio)(struct folio *, gfp_t);
381 : void (*free_folio)(struct folio *folio);
382 : ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
383 : /*
384 : * migrate the contents of a folio to the specified target. If
385 : * migrate_mode is MIGRATE_ASYNC, it must not block.
386 : */
387 : int (*migrate_folio)(struct address_space *, struct folio *dst,
388 : struct folio *src, enum migrate_mode);
389 : int (*launder_folio)(struct folio *);
390 : bool (*is_partially_uptodate) (struct folio *, size_t from,
391 : size_t count);
392 : void (*is_dirty_writeback) (struct folio *, bool *dirty, bool *wb);
393 : int (*error_remove_page)(struct address_space *, struct page *);
394 :
395 : /* swapfile support */
396 : int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
397 : sector_t *span);
398 : void (*swap_deactivate)(struct file *file);
399 : int (*swap_rw)(struct kiocb *iocb, struct iov_iter *iter);
400 : };
401 :
402 : extern const struct address_space_operations empty_aops;
403 :
404 : /**
405 : * struct address_space - Contents of a cacheable, mappable object.
406 : * @host: Owner, either the inode or the block_device.
407 : * @i_pages: Cached pages.
408 : * @invalidate_lock: Guards coherency between page cache contents and
409 : * file offset->disk block mappings in the filesystem during invalidates.
410 : * It is also used to block modification of page cache contents through
411 : * memory mappings.
412 : * @gfp_mask: Memory allocation flags to use for allocating pages.
413 : * @i_mmap_writable: Number of VM_SHARED mappings.
414 : * @nr_thps: Number of THPs in the pagecache (non-shmem only).
415 : * @i_mmap: Tree of private and shared mappings.
416 : * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
417 : * @nrpages: Number of page entries, protected by the i_pages lock.
418 : * @writeback_index: Writeback starts here.
419 : * @a_ops: Methods.
420 : * @flags: Error bits and flags (AS_*).
421 : * @wb_err: The most recent error which has occurred.
422 : * @private_lock: For use by the owner of the address_space.
423 : * @private_list: For use by the owner of the address_space.
424 : * @private_data: For use by the owner of the address_space.
425 : */
426 : struct address_space {
427 : struct inode *host;
428 : struct xarray i_pages;
429 : struct rw_semaphore invalidate_lock;
430 : gfp_t gfp_mask;
431 : atomic_t i_mmap_writable;
432 : #ifdef CONFIG_READ_ONLY_THP_FOR_FS
433 : /* number of thp, only for non-shmem files */
434 : atomic_t nr_thps;
435 : #endif
436 : struct rb_root_cached i_mmap;
437 : struct rw_semaphore i_mmap_rwsem;
438 : unsigned long nrpages;
439 : pgoff_t writeback_index;
440 : const struct address_space_operations *a_ops;
441 : unsigned long flags;
442 : errseq_t wb_err;
443 : spinlock_t private_lock;
444 : struct list_head private_list;
445 : void *private_data;
446 : } __attribute__((aligned(sizeof(long)))) __randomize_layout;
447 : /*
448 : * On most architectures that alignment is already the case; but
449 : * must be enforced here for CRIS, to let the least significant bit
450 : * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
451 : */
452 :
453 : /* XArray tags, for tagging dirty and writeback pages in the pagecache. */
454 : #define PAGECACHE_TAG_DIRTY XA_MARK_0
455 : #define PAGECACHE_TAG_WRITEBACK XA_MARK_1
456 : #define PAGECACHE_TAG_TOWRITE XA_MARK_2
457 :
458 : /*
459 : * Returns true if any of the pages in the mapping are marked with the tag.
460 : */
461 : static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
462 : {
463 0 : return xa_marked(&mapping->i_pages, tag);
464 : }
465 :
466 : static inline void i_mmap_lock_write(struct address_space *mapping)
467 : {
468 0 : down_write(&mapping->i_mmap_rwsem);
469 : }
470 :
471 : static inline int i_mmap_trylock_write(struct address_space *mapping)
472 : {
473 : return down_write_trylock(&mapping->i_mmap_rwsem);
474 : }
475 :
476 : static inline void i_mmap_unlock_write(struct address_space *mapping)
477 : {
478 0 : up_write(&mapping->i_mmap_rwsem);
479 : }
480 :
481 : static inline int i_mmap_trylock_read(struct address_space *mapping)
482 : {
483 0 : return down_read_trylock(&mapping->i_mmap_rwsem);
484 : }
485 :
486 : static inline void i_mmap_lock_read(struct address_space *mapping)
487 : {
488 0 : down_read(&mapping->i_mmap_rwsem);
489 : }
490 :
491 : static inline void i_mmap_unlock_read(struct address_space *mapping)
492 : {
493 0 : up_read(&mapping->i_mmap_rwsem);
494 : }
495 :
496 : static inline void i_mmap_assert_locked(struct address_space *mapping)
497 : {
498 : lockdep_assert_held(&mapping->i_mmap_rwsem);
499 : }
500 :
501 : static inline void i_mmap_assert_write_locked(struct address_space *mapping)
502 : {
503 : lockdep_assert_held_write(&mapping->i_mmap_rwsem);
504 : }
505 :
506 : /*
507 : * Might pages of this file be mapped into userspace?
508 : */
509 : static inline int mapping_mapped(struct address_space *mapping)
510 : {
511 : return !RB_EMPTY_ROOT(&mapping->i_mmap.rb_root);
512 : }
513 :
514 : /*
515 : * Might pages of this file have been modified in userspace?
516 : * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap
517 : * marks vma as VM_SHARED if it is shared, and the file was opened for
518 : * writing i.e. vma may be mprotected writable even if now readonly.
519 : *
520 : * If i_mmap_writable is negative, no new writable mappings are allowed. You
521 : * can only deny writable mappings, if none exists right now.
522 : */
523 : static inline int mapping_writably_mapped(struct address_space *mapping)
524 : {
525 0 : return atomic_read(&mapping->i_mmap_writable) > 0;
526 : }
527 :
528 : static inline int mapping_map_writable(struct address_space *mapping)
529 : {
530 0 : return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
531 0 : 0 : -EPERM;
532 : }
533 :
534 : static inline void mapping_unmap_writable(struct address_space *mapping)
535 : {
536 0 : atomic_dec(&mapping->i_mmap_writable);
537 : }
538 :
539 : static inline int mapping_deny_writable(struct address_space *mapping)
540 : {
541 : return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
542 : 0 : -EBUSY;
543 : }
544 :
545 : static inline void mapping_allow_writable(struct address_space *mapping)
546 : {
547 0 : atomic_inc(&mapping->i_mmap_writable);
548 : }
549 :
550 : /*
551 : * Use sequence counter to get consistent i_size on 32-bit processors.
552 : */
553 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
554 : #include <linux/seqlock.h>
555 : #define __NEED_I_SIZE_ORDERED
556 : #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
557 : #else
558 : #define i_size_ordered_init(inode) do { } while (0)
559 : #endif
560 :
561 : struct posix_acl;
562 : #define ACL_NOT_CACHED ((void *)(-1))
563 : /*
564 : * ACL_DONT_CACHE is for stacked filesystems, that rely on underlying fs to
565 : * cache the ACL. This also means that ->get_inode_acl() can be called in RCU
566 : * mode with the LOOKUP_RCU flag.
567 : */
568 : #define ACL_DONT_CACHE ((void *)(-3))
569 :
570 : static inline struct posix_acl *
571 : uncached_acl_sentinel(struct task_struct *task)
572 : {
573 : return (void *)task + 1;
574 : }
575 :
576 : static inline bool
577 : is_uncached_acl(struct posix_acl *acl)
578 : {
579 : return (long)acl & 1;
580 : }
581 :
582 : #define IOP_FASTPERM 0x0001
583 : #define IOP_LOOKUP 0x0002
584 : #define IOP_NOFOLLOW 0x0004
585 : #define IOP_XATTR 0x0008
586 : #define IOP_DEFAULT_READLINK 0x0010
587 :
588 : struct fsnotify_mark_connector;
589 :
590 : /*
591 : * Keep mostly read-only and often accessed (especially for
592 : * the RCU path lookup and 'stat' data) fields at the beginning
593 : * of the 'struct inode'
594 : */
595 : struct inode {
596 : umode_t i_mode;
597 : unsigned short i_opflags;
598 : kuid_t i_uid;
599 : kgid_t i_gid;
600 : unsigned int i_flags;
601 :
602 : #ifdef CONFIG_FS_POSIX_ACL
603 : struct posix_acl *i_acl;
604 : struct posix_acl *i_default_acl;
605 : #endif
606 :
607 : const struct inode_operations *i_op;
608 : struct super_block *i_sb;
609 : struct address_space *i_mapping;
610 :
611 : #ifdef CONFIG_SECURITY
612 : void *i_security;
613 : #endif
614 :
615 : /* Stat data, not accessed from path walking */
616 : unsigned long i_ino;
617 : /*
618 : * Filesystems may only read i_nlink directly. They shall use the
619 : * following functions for modification:
620 : *
621 : * (set|clear|inc|drop)_nlink
622 : * inode_(inc|dec)_link_count
623 : */
624 : union {
625 : const unsigned int i_nlink;
626 : unsigned int __i_nlink;
627 : };
628 : dev_t i_rdev;
629 : loff_t i_size;
630 : struct timespec64 i_atime;
631 : struct timespec64 i_mtime;
632 : struct timespec64 i_ctime;
633 : spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
634 : unsigned short i_bytes;
635 : u8 i_blkbits;
636 : u8 i_write_hint;
637 : blkcnt_t i_blocks;
638 :
639 : #ifdef __NEED_I_SIZE_ORDERED
640 : seqcount_t i_size_seqcount;
641 : #endif
642 :
643 : /* Misc */
644 : unsigned long i_state;
645 : struct rw_semaphore i_rwsem;
646 :
647 : unsigned long dirtied_when; /* jiffies of first dirtying */
648 : unsigned long dirtied_time_when;
649 :
650 : struct hlist_node i_hash;
651 : struct list_head i_io_list; /* backing dev IO list */
652 : #ifdef CONFIG_CGROUP_WRITEBACK
653 : struct bdi_writeback *i_wb; /* the associated cgroup wb */
654 :
655 : /* foreign inode detection, see wbc_detach_inode() */
656 : int i_wb_frn_winner;
657 : u16 i_wb_frn_avg_time;
658 : u16 i_wb_frn_history;
659 : #endif
660 : struct list_head i_lru; /* inode LRU list */
661 : struct list_head i_sb_list;
662 : struct list_head i_wb_list; /* backing dev writeback list */
663 : union {
664 : struct hlist_head i_dentry;
665 : struct rcu_head i_rcu;
666 : };
667 : atomic64_t i_version;
668 : atomic64_t i_sequence; /* see futex */
669 : atomic_t i_count;
670 : atomic_t i_dio_count;
671 : atomic_t i_writecount;
672 : #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
673 : atomic_t i_readcount; /* struct files open RO */
674 : #endif
675 : union {
676 : const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
677 : void (*free_inode)(struct inode *);
678 : };
679 : struct file_lock_context *i_flctx;
680 : struct address_space i_data;
681 : struct list_head i_devices;
682 : union {
683 : struct pipe_inode_info *i_pipe;
684 : struct cdev *i_cdev;
685 : char *i_link;
686 : unsigned i_dir_seq;
687 : };
688 :
689 : __u32 i_generation;
690 :
691 : #ifdef CONFIG_FSNOTIFY
692 : __u32 i_fsnotify_mask; /* all events this inode cares about */
693 : struct fsnotify_mark_connector __rcu *i_fsnotify_marks;
694 : #endif
695 :
696 : #ifdef CONFIG_FS_ENCRYPTION
697 : struct fscrypt_info *i_crypt_info;
698 : #endif
699 :
700 : #ifdef CONFIG_FS_VERITY
701 : struct fsverity_info *i_verity_info;
702 : #endif
703 :
704 : void *i_private; /* fs or device private pointer */
705 : } __randomize_layout;
706 :
707 : struct timespec64 timestamp_truncate(struct timespec64 t, struct inode *inode);
708 :
709 : static inline unsigned int i_blocksize(const struct inode *node)
710 : {
711 0 : return (1 << node->i_blkbits);
712 : }
713 :
714 : static inline int inode_unhashed(struct inode *inode)
715 : {
716 68 : return hlist_unhashed(&inode->i_hash);
717 : }
718 :
719 : /*
720 : * __mark_inode_dirty expects inodes to be hashed. Since we don't
721 : * want special inodes in the fileset inode space, we make them
722 : * appear hashed, but do not put on any lists. hlist_del()
723 : * will work fine and require no locking.
724 : */
725 : static inline void inode_fake_hash(struct inode *inode)
726 : {
727 : hlist_add_fake(&inode->i_hash);
728 : }
729 :
730 : /*
731 : * inode->i_mutex nesting subclasses for the lock validator:
732 : *
733 : * 0: the object of the current VFS operation
734 : * 1: parent
735 : * 2: child/target
736 : * 3: xattr
737 : * 4: second non-directory
738 : * 5: second parent (when locking independent directories in rename)
739 : *
740 : * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
741 : * non-directories at once.
742 : *
743 : * The locking order between these classes is
744 : * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
745 : */
746 : enum inode_i_mutex_lock_class
747 : {
748 : I_MUTEX_NORMAL,
749 : I_MUTEX_PARENT,
750 : I_MUTEX_CHILD,
751 : I_MUTEX_XATTR,
752 : I_MUTEX_NONDIR2,
753 : I_MUTEX_PARENT2,
754 : };
755 :
756 : static inline void inode_lock(struct inode *inode)
757 : {
758 2 : down_write(&inode->i_rwsem);
759 : }
760 :
761 : static inline void inode_unlock(struct inode *inode)
762 : {
763 5 : up_write(&inode->i_rwsem);
764 : }
765 :
766 : static inline void inode_lock_shared(struct inode *inode)
767 : {
768 0 : down_read(&inode->i_rwsem);
769 : }
770 :
771 : static inline void inode_unlock_shared(struct inode *inode)
772 : {
773 0 : up_read(&inode->i_rwsem);
774 : }
775 :
776 : static inline int inode_trylock(struct inode *inode)
777 : {
778 0 : return down_write_trylock(&inode->i_rwsem);
779 : }
780 :
781 : static inline int inode_trylock_shared(struct inode *inode)
782 : {
783 0 : return down_read_trylock(&inode->i_rwsem);
784 : }
785 :
786 : static inline int inode_is_locked(struct inode *inode)
787 : {
788 0 : return rwsem_is_locked(&inode->i_rwsem);
789 : }
790 :
791 : static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
792 : {
793 3 : down_write_nested(&inode->i_rwsem, subclass);
794 : }
795 :
796 : static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass)
797 : {
798 : down_read_nested(&inode->i_rwsem, subclass);
799 : }
800 :
801 : static inline void filemap_invalidate_lock(struct address_space *mapping)
802 : {
803 0 : down_write(&mapping->invalidate_lock);
804 : }
805 :
806 : static inline void filemap_invalidate_unlock(struct address_space *mapping)
807 : {
808 0 : up_write(&mapping->invalidate_lock);
809 : }
810 :
811 : static inline void filemap_invalidate_lock_shared(struct address_space *mapping)
812 : {
813 0 : down_read(&mapping->invalidate_lock);
814 : }
815 :
816 : static inline int filemap_invalidate_trylock_shared(
817 : struct address_space *mapping)
818 : {
819 0 : return down_read_trylock(&mapping->invalidate_lock);
820 : }
821 :
822 : static inline void filemap_invalidate_unlock_shared(
823 : struct address_space *mapping)
824 : {
825 0 : up_read(&mapping->invalidate_lock);
826 : }
827 :
828 : void lock_two_nondirectories(struct inode *, struct inode*);
829 : void unlock_two_nondirectories(struct inode *, struct inode*);
830 :
831 : void filemap_invalidate_lock_two(struct address_space *mapping1,
832 : struct address_space *mapping2);
833 : void filemap_invalidate_unlock_two(struct address_space *mapping1,
834 : struct address_space *mapping2);
835 :
836 :
837 : /*
838 : * NOTE: in a 32bit arch with a preemptable kernel and
839 : * an UP compile the i_size_read/write must be atomic
840 : * with respect to the local cpu (unlike with preempt disabled),
841 : * but they don't need to be atomic with respect to other cpus like in
842 : * true SMP (so they need either to either locally disable irq around
843 : * the read or for example on x86 they can be still implemented as a
844 : * cmpxchg8b without the need of the lock prefix). For SMP compiles
845 : * and 64bit archs it makes no difference if preempt is enabled or not.
846 : */
847 : static inline loff_t i_size_read(const struct inode *inode)
848 : {
849 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
850 : loff_t i_size;
851 : unsigned int seq;
852 :
853 : do {
854 : seq = read_seqcount_begin(&inode->i_size_seqcount);
855 : i_size = inode->i_size;
856 : } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
857 : return i_size;
858 : #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
859 : loff_t i_size;
860 :
861 : preempt_disable();
862 : i_size = inode->i_size;
863 : preempt_enable();
864 : return i_size;
865 : #else
866 : return inode->i_size;
867 : #endif
868 : }
869 :
870 : /*
871 : * NOTE: unlike i_size_read(), i_size_write() does need locking around it
872 : * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
873 : * can be lost, resulting in subsequent i_size_read() calls spinning forever.
874 : */
875 : static inline void i_size_write(struct inode *inode, loff_t i_size)
876 : {
877 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
878 : preempt_disable();
879 : write_seqcount_begin(&inode->i_size_seqcount);
880 : inode->i_size = i_size;
881 : write_seqcount_end(&inode->i_size_seqcount);
882 : preempt_enable();
883 : #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
884 : preempt_disable();
885 : inode->i_size = i_size;
886 : preempt_enable();
887 : #else
888 0 : inode->i_size = i_size;
889 : #endif
890 : }
891 :
892 : static inline unsigned iminor(const struct inode *inode)
893 : {
894 0 : return MINOR(inode->i_rdev);
895 : }
896 :
897 : static inline unsigned imajor(const struct inode *inode)
898 : {
899 0 : return MAJOR(inode->i_rdev);
900 : }
901 :
902 : struct fown_struct {
903 : rwlock_t lock; /* protects pid, uid, euid fields */
904 : struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
905 : enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
906 : kuid_t uid, euid; /* uid/euid of process setting the owner */
907 : int signum; /* posix.1b rt signal to be delivered on IO */
908 : };
909 :
910 : /**
911 : * struct file_ra_state - Track a file's readahead state.
912 : * @start: Where the most recent readahead started.
913 : * @size: Number of pages read in the most recent readahead.
914 : * @async_size: Numer of pages that were/are not needed immediately
915 : * and so were/are genuinely "ahead". Start next readahead when
916 : * the first of these pages is accessed.
917 : * @ra_pages: Maximum size of a readahead request, copied from the bdi.
918 : * @mmap_miss: How many mmap accesses missed in the page cache.
919 : * @prev_pos: The last byte in the most recent read request.
920 : *
921 : * When this structure is passed to ->readahead(), the "most recent"
922 : * readahead means the current readahead.
923 : */
924 : struct file_ra_state {
925 : pgoff_t start;
926 : unsigned int size;
927 : unsigned int async_size;
928 : unsigned int ra_pages;
929 : unsigned int mmap_miss;
930 : loff_t prev_pos;
931 : };
932 :
933 : /*
934 : * Check if @index falls in the readahead windows.
935 : */
936 : static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
937 : {
938 : return (index >= ra->start &&
939 : index < ra->start + ra->size);
940 : }
941 :
942 : struct file {
943 : union {
944 : struct llist_node f_llist;
945 : struct rcu_head f_rcuhead;
946 : unsigned int f_iocb_flags;
947 : };
948 : struct path f_path;
949 : struct inode *f_inode; /* cached value */
950 : const struct file_operations *f_op;
951 :
952 : /*
953 : * Protects f_ep, f_flags.
954 : * Must not be taken from IRQ context.
955 : */
956 : spinlock_t f_lock;
957 : atomic_long_t f_count;
958 : unsigned int f_flags;
959 : fmode_t f_mode;
960 : struct mutex f_pos_lock;
961 : loff_t f_pos;
962 : struct fown_struct f_owner;
963 : const struct cred *f_cred;
964 : struct file_ra_state f_ra;
965 :
966 : u64 f_version;
967 : #ifdef CONFIG_SECURITY
968 : void *f_security;
969 : #endif
970 : /* needed for tty driver, and maybe others */
971 : void *private_data;
972 :
973 : #ifdef CONFIG_EPOLL
974 : /* Used by fs/eventpoll.c to link all the hooks to this file */
975 : struct hlist_head *f_ep;
976 : #endif /* #ifdef CONFIG_EPOLL */
977 : struct address_space *f_mapping;
978 : errseq_t f_wb_err;
979 : errseq_t f_sb_err; /* for syncfs */
980 : } __randomize_layout
981 : __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
982 :
983 : struct file_handle {
984 : __u32 handle_bytes;
985 : int handle_type;
986 : /* file identifier */
987 : unsigned char f_handle[];
988 : };
989 :
990 : static inline struct file *get_file(struct file *f)
991 : {
992 0 : atomic_long_inc(&f->f_count);
993 : return f;
994 : }
995 : #define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
996 : #define file_count(x) atomic_long_read(&(x)->f_count)
997 :
998 : #define MAX_NON_LFS ((1UL<<31) - 1)
999 :
1000 : /* Page cache limit. The filesystems should put that into their s_maxbytes
1001 : limits, otherwise bad things can happen in VM. */
1002 : #if BITS_PER_LONG==32
1003 : #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
1004 : #elif BITS_PER_LONG==64
1005 : #define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
1006 : #endif
1007 :
1008 : /* legacy typedef, should eventually be removed */
1009 : typedef void *fl_owner_t;
1010 :
1011 : struct file_lock;
1012 :
1013 : /* The following constant reflects the upper bound of the file/locking space */
1014 : #ifndef OFFSET_MAX
1015 : #define OFFSET_MAX type_max(loff_t)
1016 : #define OFFT_OFFSET_MAX type_max(off_t)
1017 : #endif
1018 :
1019 : extern void send_sigio(struct fown_struct *fown, int fd, int band);
1020 :
1021 : static inline struct inode *file_inode(const struct file *f)
1022 : {
1023 : return f->f_inode;
1024 : }
1025 :
1026 : static inline struct dentry *file_dentry(const struct file *file)
1027 : {
1028 0 : return d_real(file->f_path.dentry, file_inode(file));
1029 : }
1030 :
1031 : struct fasync_struct {
1032 : rwlock_t fa_lock;
1033 : int magic;
1034 : int fa_fd;
1035 : struct fasync_struct *fa_next; /* singly linked list */
1036 : struct file *fa_file;
1037 : struct rcu_head fa_rcu;
1038 : };
1039 :
1040 : #define FASYNC_MAGIC 0x4601
1041 :
1042 : /* SMP safe fasync helpers: */
1043 : extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1044 : extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1045 : extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1046 : extern struct fasync_struct *fasync_alloc(void);
1047 : extern void fasync_free(struct fasync_struct *);
1048 :
1049 : /* can be called from interrupts */
1050 : extern void kill_fasync(struct fasync_struct **, int, int);
1051 :
1052 : extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1053 : extern int f_setown(struct file *filp, unsigned long arg, int force);
1054 : extern void f_delown(struct file *filp);
1055 : extern pid_t f_getown(struct file *filp);
1056 : extern int send_sigurg(struct fown_struct *fown);
1057 :
1058 : /*
1059 : * sb->s_flags. Note that these mirror the equivalent MS_* flags where
1060 : * represented in both.
1061 : */
1062 : #define SB_RDONLY 1 /* Mount read-only */
1063 : #define SB_NOSUID 2 /* Ignore suid and sgid bits */
1064 : #define SB_NODEV 4 /* Disallow access to device special files */
1065 : #define SB_NOEXEC 8 /* Disallow program execution */
1066 : #define SB_SYNCHRONOUS 16 /* Writes are synced at once */
1067 : #define SB_MANDLOCK 64 /* Allow mandatory locks on an FS */
1068 : #define SB_DIRSYNC 128 /* Directory modifications are synchronous */
1069 : #define SB_NOATIME 1024 /* Do not update access times. */
1070 : #define SB_NODIRATIME 2048 /* Do not update directory access times */
1071 : #define SB_SILENT 32768
1072 : #define SB_POSIXACL (1<<16) /* VFS does not apply the umask */
1073 : #define SB_INLINECRYPT (1<<17) /* Use blk-crypto for encrypted files */
1074 : #define SB_KERNMOUNT (1<<22) /* this is a kern_mount call */
1075 : #define SB_I_VERSION (1<<23) /* Update inode I_version field */
1076 : #define SB_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */
1077 :
1078 : /* These sb flags are internal to the kernel */
1079 : #define SB_SUBMOUNT (1<<26)
1080 : #define SB_FORCE (1<<27)
1081 : #define SB_NOSEC (1<<28)
1082 : #define SB_BORN (1<<29)
1083 : #define SB_ACTIVE (1<<30)
1084 : #define SB_NOUSER (1<<31)
1085 :
1086 : /* These flags relate to encoding and casefolding */
1087 : #define SB_ENC_STRICT_MODE_FL (1 << 0)
1088 :
1089 : #define sb_has_strict_encoding(sb) \
1090 : (sb->s_encoding_flags & SB_ENC_STRICT_MODE_FL)
1091 :
1092 : /*
1093 : * Umount options
1094 : */
1095 :
1096 : #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1097 : #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1098 : #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1099 : #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1100 : #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1101 :
1102 : /* sb->s_iflags */
1103 : #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1104 : #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1105 : #define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
1106 : #define SB_I_STABLE_WRITES 0x00000008 /* don't modify blks until WB is done */
1107 :
1108 : /* sb->s_iflags to limit user namespace mounts */
1109 : #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
1110 : #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
1111 : #define SB_I_UNTRUSTED_MOUNTER 0x00000040
1112 :
1113 : #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */
1114 : #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */
1115 : #define SB_I_TS_EXPIRY_WARNED 0x00000400 /* warned about timestamp range expiry */
1116 : #define SB_I_RETIRED 0x00000800 /* superblock shouldn't be reused */
1117 :
1118 : /* Possible states of 'frozen' field */
1119 : enum {
1120 : SB_UNFROZEN = 0, /* FS is unfrozen */
1121 : SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1122 : SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1123 : SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1124 : * internal threads if needed) */
1125 : SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1126 : };
1127 :
1128 : #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1129 :
1130 : struct sb_writers {
1131 : int frozen; /* Is sb frozen? */
1132 : wait_queue_head_t wait_unfrozen; /* wait for thaw */
1133 : struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
1134 : };
1135 :
1136 : struct super_block {
1137 : struct list_head s_list; /* Keep this first */
1138 : dev_t s_dev; /* search index; _not_ kdev_t */
1139 : unsigned char s_blocksize_bits;
1140 : unsigned long s_blocksize;
1141 : loff_t s_maxbytes; /* Max file size */
1142 : struct file_system_type *s_type;
1143 : const struct super_operations *s_op;
1144 : const struct dquot_operations *dq_op;
1145 : const struct quotactl_ops *s_qcop;
1146 : const struct export_operations *s_export_op;
1147 : unsigned long s_flags;
1148 : unsigned long s_iflags; /* internal SB_I_* flags */
1149 : unsigned long s_magic;
1150 : struct dentry *s_root;
1151 : struct rw_semaphore s_umount;
1152 : int s_count;
1153 : atomic_t s_active;
1154 : #ifdef CONFIG_SECURITY
1155 : void *s_security;
1156 : #endif
1157 : const struct xattr_handler **s_xattr;
1158 : #ifdef CONFIG_FS_ENCRYPTION
1159 : const struct fscrypt_operations *s_cop;
1160 : struct fscrypt_keyring *s_master_keys; /* master crypto keys in use */
1161 : #endif
1162 : #ifdef CONFIG_FS_VERITY
1163 : const struct fsverity_operations *s_vop;
1164 : #endif
1165 : #if IS_ENABLED(CONFIG_UNICODE)
1166 : struct unicode_map *s_encoding;
1167 : __u16 s_encoding_flags;
1168 : #endif
1169 : struct hlist_bl_head s_roots; /* alternate root dentries for NFS */
1170 : struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1171 : struct block_device *s_bdev;
1172 : struct backing_dev_info *s_bdi;
1173 : struct mtd_info *s_mtd;
1174 : struct hlist_node s_instances;
1175 : unsigned int s_quota_types; /* Bitmask of supported quota types */
1176 : struct quota_info s_dquot; /* Diskquota specific options */
1177 :
1178 : struct sb_writers s_writers;
1179 :
1180 : /*
1181 : * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
1182 : * s_fsnotify_marks together for cache efficiency. They are frequently
1183 : * accessed and rarely modified.
1184 : */
1185 : void *s_fs_info; /* Filesystem private info */
1186 :
1187 : /* Granularity of c/m/atime in ns (cannot be worse than a second) */
1188 : u32 s_time_gran;
1189 : /* Time limits for c/m/atime in seconds */
1190 : time64_t s_time_min;
1191 : time64_t s_time_max;
1192 : #ifdef CONFIG_FSNOTIFY
1193 : __u32 s_fsnotify_mask;
1194 : struct fsnotify_mark_connector __rcu *s_fsnotify_marks;
1195 : #endif
1196 :
1197 : char s_id[32]; /* Informational name */
1198 : uuid_t s_uuid; /* UUID */
1199 :
1200 : unsigned int s_max_links;
1201 : fmode_t s_mode;
1202 :
1203 : /*
1204 : * The next field is for VFS *only*. No filesystems have any business
1205 : * even looking at it. You had been warned.
1206 : */
1207 : struct mutex s_vfs_rename_mutex; /* Kludge */
1208 :
1209 : /*
1210 : * Filesystem subtype. If non-empty the filesystem type field
1211 : * in /proc/mounts will be "type.subtype"
1212 : */
1213 : const char *s_subtype;
1214 :
1215 : const struct dentry_operations *s_d_op; /* default d_op for dentries */
1216 :
1217 : struct shrinker s_shrink; /* per-sb shrinker handle */
1218 :
1219 : /* Number of inodes with nlink == 0 but still referenced */
1220 : atomic_long_t s_remove_count;
1221 :
1222 : /*
1223 : * Number of inode/mount/sb objects that are being watched, note that
1224 : * inodes objects are currently double-accounted.
1225 : */
1226 : atomic_long_t s_fsnotify_connectors;
1227 :
1228 : /* Being remounted read-only */
1229 : int s_readonly_remount;
1230 :
1231 : /* per-sb errseq_t for reporting writeback errors via syncfs */
1232 : errseq_t s_wb_err;
1233 :
1234 : /* AIO completions deferred from interrupt context */
1235 : struct workqueue_struct *s_dio_done_wq;
1236 : struct hlist_head s_pins;
1237 :
1238 : /*
1239 : * Owning user namespace and default context in which to
1240 : * interpret filesystem uids, gids, quotas, device nodes,
1241 : * xattrs and security labels.
1242 : */
1243 : struct user_namespace *s_user_ns;
1244 :
1245 : /*
1246 : * The list_lru structure is essentially just a pointer to a table
1247 : * of per-node lru lists, each of which has its own spinlock.
1248 : * There is no need to put them into separate cachelines.
1249 : */
1250 : struct list_lru s_dentry_lru;
1251 : struct list_lru s_inode_lru;
1252 : struct rcu_head rcu;
1253 : struct work_struct destroy_work;
1254 :
1255 : struct mutex s_sync_lock; /* sync serialisation lock */
1256 :
1257 : /*
1258 : * Indicates how deep in a filesystem stack this SB is
1259 : */
1260 : int s_stack_depth;
1261 :
1262 : /* s_inode_list_lock protects s_inodes */
1263 : spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
1264 : struct list_head s_inodes; /* all inodes */
1265 :
1266 : spinlock_t s_inode_wblist_lock;
1267 : struct list_head s_inodes_wb; /* writeback inodes */
1268 : } __randomize_layout;
1269 :
1270 : static inline struct user_namespace *i_user_ns(const struct inode *inode)
1271 : {
1272 26 : return inode->i_sb->s_user_ns;
1273 : }
1274 :
1275 : /* Helper functions so that in most cases filesystems will
1276 : * not need to deal directly with kuid_t and kgid_t and can
1277 : * instead deal with the raw numeric values that are stored
1278 : * in the filesystem.
1279 : */
1280 : static inline uid_t i_uid_read(const struct inode *inode)
1281 : {
1282 : return from_kuid(i_user_ns(inode), inode->i_uid);
1283 : }
1284 :
1285 : static inline gid_t i_gid_read(const struct inode *inode)
1286 : {
1287 : return from_kgid(i_user_ns(inode), inode->i_gid);
1288 : }
1289 :
1290 : static inline void i_uid_write(struct inode *inode, uid_t uid)
1291 : {
1292 51 : inode->i_uid = make_kuid(i_user_ns(inode), uid);
1293 : }
1294 :
1295 : static inline void i_gid_write(struct inode *inode, gid_t gid)
1296 : {
1297 51 : inode->i_gid = make_kgid(i_user_ns(inode), gid);
1298 : }
1299 :
1300 : /**
1301 : * i_uid_into_vfsuid - map an inode's i_uid down according to an idmapping
1302 : * @idmap: idmap of the mount the inode was found from
1303 : * @inode: inode to map
1304 : *
1305 : * Return: whe inode's i_uid mapped down according to @idmap.
1306 : * If the inode's i_uid has no mapping INVALID_VFSUID is returned.
1307 : */
1308 : static inline vfsuid_t i_uid_into_vfsuid(struct mnt_idmap *idmap,
1309 : const struct inode *inode)
1310 : {
1311 26 : return make_vfsuid(idmap, i_user_ns(inode), inode->i_uid);
1312 : }
1313 :
1314 : /**
1315 : * i_uid_needs_update - check whether inode's i_uid needs to be updated
1316 : * @idmap: idmap of the mount the inode was found from
1317 : * @attr: the new attributes of @inode
1318 : * @inode: the inode to update
1319 : *
1320 : * Check whether the $inode's i_uid field needs to be updated taking idmapped
1321 : * mounts into account if the filesystem supports it.
1322 : *
1323 : * Return: true if @inode's i_uid field needs to be updated, false if not.
1324 : */
1325 : static inline bool i_uid_needs_update(struct mnt_idmap *idmap,
1326 : const struct iattr *attr,
1327 : const struct inode *inode)
1328 : {
1329 : return ((attr->ia_valid & ATTR_UID) &&
1330 : !vfsuid_eq(attr->ia_vfsuid,
1331 : i_uid_into_vfsuid(idmap, inode)));
1332 : }
1333 :
1334 : /**
1335 : * i_uid_update - update @inode's i_uid field
1336 : * @idmap: idmap of the mount the inode was found from
1337 : * @attr: the new attributes of @inode
1338 : * @inode: the inode to update
1339 : *
1340 : * Safely update @inode's i_uid field translating the vfsuid of any idmapped
1341 : * mount into the filesystem kuid.
1342 : */
1343 : static inline void i_uid_update(struct mnt_idmap *idmap,
1344 : const struct iattr *attr,
1345 : struct inode *inode)
1346 : {
1347 0 : if (attr->ia_valid & ATTR_UID)
1348 0 : inode->i_uid = from_vfsuid(idmap, i_user_ns(inode),
1349 : attr->ia_vfsuid);
1350 : }
1351 :
1352 : /**
1353 : * i_gid_into_vfsgid - map an inode's i_gid down according to an idmapping
1354 : * @idmap: idmap of the mount the inode was found from
1355 : * @inode: inode to map
1356 : *
1357 : * Return: the inode's i_gid mapped down according to @idmap.
1358 : * If the inode's i_gid has no mapping INVALID_VFSGID is returned.
1359 : */
1360 : static inline vfsgid_t i_gid_into_vfsgid(struct mnt_idmap *idmap,
1361 : const struct inode *inode)
1362 : {
1363 6 : return make_vfsgid(idmap, i_user_ns(inode), inode->i_gid);
1364 : }
1365 :
1366 : /**
1367 : * i_gid_needs_update - check whether inode's i_gid needs to be updated
1368 : * @idmap: idmap of the mount the inode was found from
1369 : * @attr: the new attributes of @inode
1370 : * @inode: the inode to update
1371 : *
1372 : * Check whether the $inode's i_gid field needs to be updated taking idmapped
1373 : * mounts into account if the filesystem supports it.
1374 : *
1375 : * Return: true if @inode's i_gid field needs to be updated, false if not.
1376 : */
1377 : static inline bool i_gid_needs_update(struct mnt_idmap *idmap,
1378 : const struct iattr *attr,
1379 : const struct inode *inode)
1380 : {
1381 : return ((attr->ia_valid & ATTR_GID) &&
1382 : !vfsgid_eq(attr->ia_vfsgid,
1383 : i_gid_into_vfsgid(idmap, inode)));
1384 : }
1385 :
1386 : /**
1387 : * i_gid_update - update @inode's i_gid field
1388 : * @idmap: idmap of the mount the inode was found from
1389 : * @attr: the new attributes of @inode
1390 : * @inode: the inode to update
1391 : *
1392 : * Safely update @inode's i_gid field translating the vfsgid of any idmapped
1393 : * mount into the filesystem kgid.
1394 : */
1395 : static inline void i_gid_update(struct mnt_idmap *idmap,
1396 : const struct iattr *attr,
1397 : struct inode *inode)
1398 : {
1399 0 : if (attr->ia_valid & ATTR_GID)
1400 0 : inode->i_gid = from_vfsgid(idmap, i_user_ns(inode),
1401 : attr->ia_vfsgid);
1402 : }
1403 :
1404 : /**
1405 : * inode_fsuid_set - initialize inode's i_uid field with callers fsuid
1406 : * @inode: inode to initialize
1407 : * @idmap: idmap of the mount the inode was found from
1408 : *
1409 : * Initialize the i_uid field of @inode. If the inode was found/created via
1410 : * an idmapped mount map the caller's fsuid according to @idmap.
1411 : */
1412 5 : static inline void inode_fsuid_set(struct inode *inode,
1413 : struct mnt_idmap *idmap)
1414 : {
1415 15 : inode->i_uid = mapped_fsuid(idmap, i_user_ns(inode));
1416 5 : }
1417 :
1418 : /**
1419 : * inode_fsgid_set - initialize inode's i_gid field with callers fsgid
1420 : * @inode: inode to initialize
1421 : * @idmap: idmap of the mount the inode was found from
1422 : *
1423 : * Initialize the i_gid field of @inode. If the inode was found/created via
1424 : * an idmapped mount map the caller's fsgid according to @idmap.
1425 : */
1426 5 : static inline void inode_fsgid_set(struct inode *inode,
1427 : struct mnt_idmap *idmap)
1428 : {
1429 15 : inode->i_gid = mapped_fsgid(idmap, i_user_ns(inode));
1430 5 : }
1431 :
1432 : /**
1433 : * fsuidgid_has_mapping() - check whether caller's fsuid/fsgid is mapped
1434 : * @sb: the superblock we want a mapping in
1435 : * @idmap: idmap of the relevant mount
1436 : *
1437 : * Check whether the caller's fsuid and fsgid have a valid mapping in the
1438 : * s_user_ns of the superblock @sb. If the caller is on an idmapped mount map
1439 : * the caller's fsuid and fsgid according to the @idmap first.
1440 : *
1441 : * Return: true if fsuid and fsgid is mapped, false if not.
1442 : */
1443 3 : static inline bool fsuidgid_has_mapping(struct super_block *sb,
1444 : struct mnt_idmap *idmap)
1445 : {
1446 3 : struct user_namespace *fs_userns = sb->s_user_ns;
1447 : kuid_t kuid;
1448 : kgid_t kgid;
1449 :
1450 3 : kuid = mapped_fsuid(idmap, fs_userns);
1451 3 : if (!uid_valid(kuid))
1452 : return false;
1453 3 : kgid = mapped_fsgid(idmap, fs_userns);
1454 3 : if (!gid_valid(kgid))
1455 : return false;
1456 : return kuid_has_mapping(fs_userns, kuid) &&
1457 : kgid_has_mapping(fs_userns, kgid);
1458 : }
1459 :
1460 : extern struct timespec64 current_time(struct inode *inode);
1461 :
1462 : /*
1463 : * Snapshotting support.
1464 : */
1465 :
1466 : /*
1467 : * These are internal functions, please use sb_start_{write,pagefault,intwrite}
1468 : * instead.
1469 : */
1470 : static inline void __sb_end_write(struct super_block *sb, int level)
1471 : {
1472 3 : percpu_up_read(sb->s_writers.rw_sem + level-1);
1473 : }
1474 :
1475 : static inline void __sb_start_write(struct super_block *sb, int level)
1476 : {
1477 3 : percpu_down_read(sb->s_writers.rw_sem + level - 1);
1478 : }
1479 :
1480 : static inline bool __sb_start_write_trylock(struct super_block *sb, int level)
1481 : {
1482 0 : return percpu_down_read_trylock(sb->s_writers.rw_sem + level - 1);
1483 : }
1484 :
1485 : #define __sb_writers_acquired(sb, lev) \
1486 : percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1487 : #define __sb_writers_release(sb, lev) \
1488 : percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1489 :
1490 : static inline bool sb_write_started(const struct super_block *sb)
1491 : {
1492 : return lockdep_is_held_type(sb->s_writers.rw_sem + SB_FREEZE_WRITE - 1, 1);
1493 : }
1494 :
1495 : /**
1496 : * sb_end_write - drop write access to a superblock
1497 : * @sb: the super we wrote to
1498 : *
1499 : * Decrement number of writers to the filesystem. Wake up possible waiters
1500 : * wanting to freeze the filesystem.
1501 : */
1502 : static inline void sb_end_write(struct super_block *sb)
1503 : {
1504 3 : __sb_end_write(sb, SB_FREEZE_WRITE);
1505 : }
1506 :
1507 : /**
1508 : * sb_end_pagefault - drop write access to a superblock from a page fault
1509 : * @sb: the super we wrote to
1510 : *
1511 : * Decrement number of processes handling write page fault to the filesystem.
1512 : * Wake up possible waiters wanting to freeze the filesystem.
1513 : */
1514 : static inline void sb_end_pagefault(struct super_block *sb)
1515 : {
1516 0 : __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1517 : }
1518 :
1519 : /**
1520 : * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1521 : * @sb: the super we wrote to
1522 : *
1523 : * Decrement fs-internal number of writers to the filesystem. Wake up possible
1524 : * waiters wanting to freeze the filesystem.
1525 : */
1526 : static inline void sb_end_intwrite(struct super_block *sb)
1527 : {
1528 : __sb_end_write(sb, SB_FREEZE_FS);
1529 : }
1530 :
1531 : /**
1532 : * sb_start_write - get write access to a superblock
1533 : * @sb: the super we write to
1534 : *
1535 : * When a process wants to write data or metadata to a file system (i.e. dirty
1536 : * a page or an inode), it should embed the operation in a sb_start_write() -
1537 : * sb_end_write() pair to get exclusion against file system freezing. This
1538 : * function increments number of writers preventing freezing. If the file
1539 : * system is already frozen, the function waits until the file system is
1540 : * thawed.
1541 : *
1542 : * Since freeze protection behaves as a lock, users have to preserve
1543 : * ordering of freeze protection and other filesystem locks. Generally,
1544 : * freeze protection should be the outermost lock. In particular, we have:
1545 : *
1546 : * sb_start_write
1547 : * -> i_mutex (write path, truncate, directory ops, ...)
1548 : * -> s_umount (freeze_super, thaw_super)
1549 : */
1550 : static inline void sb_start_write(struct super_block *sb)
1551 : {
1552 3 : __sb_start_write(sb, SB_FREEZE_WRITE);
1553 : }
1554 :
1555 : static inline bool sb_start_write_trylock(struct super_block *sb)
1556 : {
1557 0 : return __sb_start_write_trylock(sb, SB_FREEZE_WRITE);
1558 : }
1559 :
1560 : /**
1561 : * sb_start_pagefault - get write access to a superblock from a page fault
1562 : * @sb: the super we write to
1563 : *
1564 : * When a process starts handling write page fault, it should embed the
1565 : * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1566 : * exclusion against file system freezing. This is needed since the page fault
1567 : * is going to dirty a page. This function increments number of running page
1568 : * faults preventing freezing. If the file system is already frozen, the
1569 : * function waits until the file system is thawed.
1570 : *
1571 : * Since page fault freeze protection behaves as a lock, users have to preserve
1572 : * ordering of freeze protection and other filesystem locks. It is advised to
1573 : * put sb_start_pagefault() close to mmap_lock in lock ordering. Page fault
1574 : * handling code implies lock dependency:
1575 : *
1576 : * mmap_lock
1577 : * -> sb_start_pagefault
1578 : */
1579 : static inline void sb_start_pagefault(struct super_block *sb)
1580 : {
1581 0 : __sb_start_write(sb, SB_FREEZE_PAGEFAULT);
1582 : }
1583 :
1584 : /**
1585 : * sb_start_intwrite - get write access to a superblock for internal fs purposes
1586 : * @sb: the super we write to
1587 : *
1588 : * This is the third level of protection against filesystem freezing. It is
1589 : * free for use by a filesystem. The only requirement is that it must rank
1590 : * below sb_start_pagefault.
1591 : *
1592 : * For example filesystem can call sb_start_intwrite() when starting a
1593 : * transaction which somewhat eases handling of freezing for internal sources
1594 : * of filesystem changes (internal fs threads, discarding preallocation on file
1595 : * close, etc.).
1596 : */
1597 : static inline void sb_start_intwrite(struct super_block *sb)
1598 : {
1599 : __sb_start_write(sb, SB_FREEZE_FS);
1600 : }
1601 :
1602 : static inline bool sb_start_intwrite_trylock(struct super_block *sb)
1603 : {
1604 : return __sb_start_write_trylock(sb, SB_FREEZE_FS);
1605 : }
1606 :
1607 : bool inode_owner_or_capable(struct mnt_idmap *idmap,
1608 : const struct inode *inode);
1609 :
1610 : /*
1611 : * VFS helper functions..
1612 : */
1613 : int vfs_create(struct mnt_idmap *, struct inode *,
1614 : struct dentry *, umode_t, bool);
1615 : int vfs_mkdir(struct mnt_idmap *, struct inode *,
1616 : struct dentry *, umode_t);
1617 : int vfs_mknod(struct mnt_idmap *, struct inode *, struct dentry *,
1618 : umode_t, dev_t);
1619 : int vfs_symlink(struct mnt_idmap *, struct inode *,
1620 : struct dentry *, const char *);
1621 : int vfs_link(struct dentry *, struct mnt_idmap *, struct inode *,
1622 : struct dentry *, struct inode **);
1623 : int vfs_rmdir(struct mnt_idmap *, struct inode *, struct dentry *);
1624 : int vfs_unlink(struct mnt_idmap *, struct inode *, struct dentry *,
1625 : struct inode **);
1626 :
1627 : /**
1628 : * struct renamedata - contains all information required for renaming
1629 : * @old_mnt_idmap: idmap of the old mount the inode was found from
1630 : * @old_dir: parent of source
1631 : * @old_dentry: source
1632 : * @new_mnt_idmap: idmap of the new mount the inode was found from
1633 : * @new_dir: parent of destination
1634 : * @new_dentry: destination
1635 : * @delegated_inode: returns an inode needing a delegation break
1636 : * @flags: rename flags
1637 : */
1638 : struct renamedata {
1639 : struct mnt_idmap *old_mnt_idmap;
1640 : struct inode *old_dir;
1641 : struct dentry *old_dentry;
1642 : struct mnt_idmap *new_mnt_idmap;
1643 : struct inode *new_dir;
1644 : struct dentry *new_dentry;
1645 : struct inode **delegated_inode;
1646 : unsigned int flags;
1647 : } __randomize_layout;
1648 :
1649 : int vfs_rename(struct renamedata *);
1650 :
1651 : static inline int vfs_whiteout(struct mnt_idmap *idmap,
1652 : struct inode *dir, struct dentry *dentry)
1653 : {
1654 : return vfs_mknod(idmap, dir, dentry, S_IFCHR | WHITEOUT_MODE,
1655 : WHITEOUT_DEV);
1656 : }
1657 :
1658 : struct file *vfs_tmpfile_open(struct mnt_idmap *idmap,
1659 : const struct path *parentpath,
1660 : umode_t mode, int open_flag, const struct cred *cred);
1661 :
1662 : int vfs_mkobj(struct dentry *, umode_t,
1663 : int (*f)(struct dentry *, umode_t, void *),
1664 : void *);
1665 :
1666 : int vfs_fchown(struct file *file, uid_t user, gid_t group);
1667 : int vfs_fchmod(struct file *file, umode_t mode);
1668 : int vfs_utimes(const struct path *path, struct timespec64 *times);
1669 :
1670 : extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1671 :
1672 : #ifdef CONFIG_COMPAT
1673 : extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
1674 : unsigned long arg);
1675 : #else
1676 : #define compat_ptr_ioctl NULL
1677 : #endif
1678 :
1679 : /*
1680 : * VFS file helper functions.
1681 : */
1682 : void inode_init_owner(struct mnt_idmap *idmap, struct inode *inode,
1683 : const struct inode *dir, umode_t mode);
1684 : extern bool may_open_dev(const struct path *path);
1685 : umode_t mode_strip_sgid(struct mnt_idmap *idmap,
1686 : const struct inode *dir, umode_t mode);
1687 :
1688 : /*
1689 : * This is the "filldir" function type, used by readdir() to let
1690 : * the kernel specify what kind of dirent layout it wants to have.
1691 : * This allows the kernel to read directories into kernel space or
1692 : * to have different dirent layouts depending on the binary type.
1693 : * Return 'true' to keep going and 'false' if there are no more entries.
1694 : */
1695 : struct dir_context;
1696 : typedef bool (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
1697 : unsigned);
1698 :
1699 : struct dir_context {
1700 : filldir_t actor;
1701 : loff_t pos;
1702 : };
1703 :
1704 : /*
1705 : * These flags let !MMU mmap() govern direct device mapping vs immediate
1706 : * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1707 : *
1708 : * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1709 : * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1710 : * NOMMU_MAP_READ: Can be mapped for reading
1711 : * NOMMU_MAP_WRITE: Can be mapped for writing
1712 : * NOMMU_MAP_EXEC: Can be mapped for execution
1713 : */
1714 : #define NOMMU_MAP_COPY 0x00000001
1715 : #define NOMMU_MAP_DIRECT 0x00000008
1716 : #define NOMMU_MAP_READ VM_MAYREAD
1717 : #define NOMMU_MAP_WRITE VM_MAYWRITE
1718 : #define NOMMU_MAP_EXEC VM_MAYEXEC
1719 :
1720 : #define NOMMU_VMFLAGS \
1721 : (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1722 :
1723 : /*
1724 : * These flags control the behavior of the remap_file_range function pointer.
1725 : * If it is called with len == 0 that means "remap to end of source file".
1726 : * See Documentation/filesystems/vfs.rst for more details about this call.
1727 : *
1728 : * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate)
1729 : * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request
1730 : */
1731 : #define REMAP_FILE_DEDUP (1 << 0)
1732 : #define REMAP_FILE_CAN_SHORTEN (1 << 1)
1733 :
1734 : /*
1735 : * These flags signal that the caller is ok with altering various aspects of
1736 : * the behavior of the remap operation. The changes must be made by the
1737 : * implementation; the vfs remap helper functions can take advantage of them.
1738 : * Flags in this category exist to preserve the quirky behavior of the hoisted
1739 : * btrfs clone/dedupe ioctls.
1740 : */
1741 : #define REMAP_FILE_ADVISORY (REMAP_FILE_CAN_SHORTEN)
1742 :
1743 : /*
1744 : * These flags control the behavior of vfs_copy_file_range().
1745 : * They are not available to the user via syscall.
1746 : *
1747 : * COPY_FILE_SPLICE: call splice direct instead of fs clone/copy ops
1748 : */
1749 : #define COPY_FILE_SPLICE (1 << 0)
1750 :
1751 : struct iov_iter;
1752 : struct io_uring_cmd;
1753 :
1754 : struct file_operations {
1755 : struct module *owner;
1756 : loff_t (*llseek) (struct file *, loff_t, int);
1757 : ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1758 : ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1759 : ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1760 : ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1761 : int (*iopoll)(struct kiocb *kiocb, struct io_comp_batch *,
1762 : unsigned int flags);
1763 : int (*iterate) (struct file *, struct dir_context *);
1764 : int (*iterate_shared) (struct file *, struct dir_context *);
1765 : __poll_t (*poll) (struct file *, struct poll_table_struct *);
1766 : long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1767 : long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1768 : int (*mmap) (struct file *, struct vm_area_struct *);
1769 : unsigned long mmap_supported_flags;
1770 : int (*open) (struct inode *, struct file *);
1771 : int (*flush) (struct file *, fl_owner_t id);
1772 : int (*release) (struct inode *, struct file *);
1773 : int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1774 : int (*fasync) (int, struct file *, int);
1775 : int (*lock) (struct file *, int, struct file_lock *);
1776 : ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1777 : unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1778 : int (*check_flags)(int);
1779 : int (*flock) (struct file *, int, struct file_lock *);
1780 : ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1781 : ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1782 : int (*setlease)(struct file *, long, struct file_lock **, void **);
1783 : long (*fallocate)(struct file *file, int mode, loff_t offset,
1784 : loff_t len);
1785 : void (*show_fdinfo)(struct seq_file *m, struct file *f);
1786 : #ifndef CONFIG_MMU
1787 : unsigned (*mmap_capabilities)(struct file *);
1788 : #endif
1789 : ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
1790 : loff_t, size_t, unsigned int);
1791 : loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
1792 : struct file *file_out, loff_t pos_out,
1793 : loff_t len, unsigned int remap_flags);
1794 : int (*fadvise)(struct file *, loff_t, loff_t, int);
1795 : int (*uring_cmd)(struct io_uring_cmd *ioucmd, unsigned int issue_flags);
1796 : int (*uring_cmd_iopoll)(struct io_uring_cmd *, struct io_comp_batch *,
1797 : unsigned int poll_flags);
1798 : } __randomize_layout;
1799 :
1800 : struct inode_operations {
1801 : struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1802 : const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
1803 : int (*permission) (struct mnt_idmap *, struct inode *, int);
1804 : struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);
1805 :
1806 : int (*readlink) (struct dentry *, char __user *,int);
1807 :
1808 : int (*create) (struct mnt_idmap *, struct inode *,struct dentry *,
1809 : umode_t, bool);
1810 : int (*link) (struct dentry *,struct inode *,struct dentry *);
1811 : int (*unlink) (struct inode *,struct dentry *);
1812 : int (*symlink) (struct mnt_idmap *, struct inode *,struct dentry *,
1813 : const char *);
1814 : int (*mkdir) (struct mnt_idmap *, struct inode *,struct dentry *,
1815 : umode_t);
1816 : int (*rmdir) (struct inode *,struct dentry *);
1817 : int (*mknod) (struct mnt_idmap *, struct inode *,struct dentry *,
1818 : umode_t,dev_t);
1819 : int (*rename) (struct mnt_idmap *, struct inode *, struct dentry *,
1820 : struct inode *, struct dentry *, unsigned int);
1821 : int (*setattr) (struct mnt_idmap *, struct dentry *, struct iattr *);
1822 : int (*getattr) (struct mnt_idmap *, const struct path *,
1823 : struct kstat *, u32, unsigned int);
1824 : ssize_t (*listxattr) (struct dentry *, char *, size_t);
1825 : int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1826 : u64 len);
1827 : int (*update_time)(struct inode *, struct timespec64 *, int);
1828 : int (*atomic_open)(struct inode *, struct dentry *,
1829 : struct file *, unsigned open_flag,
1830 : umode_t create_mode);
1831 : int (*tmpfile) (struct mnt_idmap *, struct inode *,
1832 : struct file *, umode_t);
1833 : struct posix_acl *(*get_acl)(struct mnt_idmap *, struct dentry *,
1834 : int);
1835 : int (*set_acl)(struct mnt_idmap *, struct dentry *,
1836 : struct posix_acl *, int);
1837 : int (*fileattr_set)(struct mnt_idmap *idmap,
1838 : struct dentry *dentry, struct fileattr *fa);
1839 : int (*fileattr_get)(struct dentry *dentry, struct fileattr *fa);
1840 : } ____cacheline_aligned;
1841 :
1842 : static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
1843 : struct iov_iter *iter)
1844 : {
1845 0 : return file->f_op->read_iter(kio, iter);
1846 : }
1847 :
1848 : static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
1849 : struct iov_iter *iter)
1850 : {
1851 0 : return file->f_op->write_iter(kio, iter);
1852 : }
1853 :
1854 : static inline int call_mmap(struct file *file, struct vm_area_struct *vma)
1855 : {
1856 0 : return file->f_op->mmap(file, vma);
1857 : }
1858 :
1859 : extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1860 : extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1861 : extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
1862 : loff_t, size_t, unsigned int);
1863 : extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in,
1864 : struct file *file_out, loff_t pos_out,
1865 : size_t len, unsigned int flags);
1866 : int __generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
1867 : struct file *file_out, loff_t pos_out,
1868 : loff_t *len, unsigned int remap_flags,
1869 : const struct iomap_ops *dax_read_ops);
1870 : int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
1871 : struct file *file_out, loff_t pos_out,
1872 : loff_t *count, unsigned int remap_flags);
1873 : extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
1874 : struct file *file_out, loff_t pos_out,
1875 : loff_t len, unsigned int remap_flags);
1876 : extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
1877 : struct file *file_out, loff_t pos_out,
1878 : loff_t len, unsigned int remap_flags);
1879 : extern int vfs_dedupe_file_range(struct file *file,
1880 : struct file_dedupe_range *same);
1881 : extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
1882 : struct file *dst_file, loff_t dst_pos,
1883 : loff_t len, unsigned int remap_flags);
1884 :
1885 :
1886 : struct super_operations {
1887 : struct inode *(*alloc_inode)(struct super_block *sb);
1888 : void (*destroy_inode)(struct inode *);
1889 : void (*free_inode)(struct inode *);
1890 :
1891 : void (*dirty_inode) (struct inode *, int flags);
1892 : int (*write_inode) (struct inode *, struct writeback_control *wbc);
1893 : int (*drop_inode) (struct inode *);
1894 : void (*evict_inode) (struct inode *);
1895 : void (*put_super) (struct super_block *);
1896 : int (*sync_fs)(struct super_block *sb, int wait);
1897 : int (*freeze_super) (struct super_block *);
1898 : int (*freeze_fs) (struct super_block *);
1899 : int (*thaw_super) (struct super_block *);
1900 : int (*unfreeze_fs) (struct super_block *);
1901 : int (*statfs) (struct dentry *, struct kstatfs *);
1902 : int (*remount_fs) (struct super_block *, int *, char *);
1903 : void (*umount_begin) (struct super_block *);
1904 :
1905 : int (*show_options)(struct seq_file *, struct dentry *);
1906 : int (*show_devname)(struct seq_file *, struct dentry *);
1907 : int (*show_path)(struct seq_file *, struct dentry *);
1908 : int (*show_stats)(struct seq_file *, struct dentry *);
1909 : #ifdef CONFIG_QUOTA
1910 : ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1911 : ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1912 : struct dquot **(*get_dquots)(struct inode *);
1913 : #endif
1914 : long (*nr_cached_objects)(struct super_block *,
1915 : struct shrink_control *);
1916 : long (*free_cached_objects)(struct super_block *,
1917 : struct shrink_control *);
1918 : };
1919 :
1920 : /*
1921 : * Inode flags - they have no relation to superblock flags now
1922 : */
1923 : #define S_SYNC (1 << 0) /* Writes are synced at once */
1924 : #define S_NOATIME (1 << 1) /* Do not update access times */
1925 : #define S_APPEND (1 << 2) /* Append-only file */
1926 : #define S_IMMUTABLE (1 << 3) /* Immutable file */
1927 : #define S_DEAD (1 << 4) /* removed, but still open directory */
1928 : #define S_NOQUOTA (1 << 5) /* Inode is not counted to quota */
1929 : #define S_DIRSYNC (1 << 6) /* Directory modifications are synchronous */
1930 : #define S_NOCMTIME (1 << 7) /* Do not update file c/mtime */
1931 : #define S_SWAPFILE (1 << 8) /* Do not truncate: swapon got its bmaps */
1932 : #define S_PRIVATE (1 << 9) /* Inode is fs-internal */
1933 : #define S_IMA (1 << 10) /* Inode has an associated IMA struct */
1934 : #define S_AUTOMOUNT (1 << 11) /* Automount/referral quasi-directory */
1935 : #define S_NOSEC (1 << 12) /* no suid or xattr security attributes */
1936 : #ifdef CONFIG_FS_DAX
1937 : #define S_DAX (1 << 13) /* Direct Access, avoiding the page cache */
1938 : #else
1939 : #define S_DAX 0 /* Make all the DAX code disappear */
1940 : #endif
1941 : #define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
1942 : #define S_CASEFOLD (1 << 15) /* Casefolded file */
1943 : #define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
1944 : #define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
1945 :
1946 : /*
1947 : * Note that nosuid etc flags are inode-specific: setting some file-system
1948 : * flags just means all the inodes inherit those flags by default. It might be
1949 : * possible to override it selectively if you really wanted to with some
1950 : * ioctl() that is not currently implemented.
1951 : *
1952 : * Exception: SB_RDONLY is always applied to the entire file system.
1953 : *
1954 : * Unfortunately, it is possible to change a filesystems flags with it mounted
1955 : * with files in use. This means that all of the inodes will not have their
1956 : * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1957 : * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1958 : */
1959 : #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1960 :
1961 23 : static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags & SB_RDONLY; }
1962 : #define IS_RDONLY(inode) sb_rdonly((inode)->i_sb)
1963 : #define IS_SYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS) || \
1964 : ((inode)->i_flags & S_SYNC))
1965 : #define IS_DIRSYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
1966 : ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1967 : #define IS_MANDLOCK(inode) __IS_FLG(inode, SB_MANDLOCK)
1968 : #define IS_NOATIME(inode) __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
1969 : #define IS_I_VERSION(inode) __IS_FLG(inode, SB_I_VERSION)
1970 :
1971 : #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1972 : #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1973 : #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1974 : #define IS_POSIXACL(inode) __IS_FLG(inode, SB_POSIXACL)
1975 :
1976 : #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1977 : #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1978 : #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1979 : #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1980 : #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1981 : #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1982 : #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
1983 : #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
1984 : #define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED)
1985 : #define IS_CASEFOLDED(inode) ((inode)->i_flags & S_CASEFOLD)
1986 : #define IS_VERITY(inode) ((inode)->i_flags & S_VERITY)
1987 :
1988 : #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
1989 : (inode)->i_rdev == WHITEOUT_DEV)
1990 :
1991 3 : static inline bool HAS_UNMAPPED_ID(struct mnt_idmap *idmap,
1992 : struct inode *inode)
1993 : {
1994 6 : return !vfsuid_valid(i_uid_into_vfsuid(idmap, inode)) ||
1995 3 : !vfsgid_valid(i_gid_into_vfsgid(idmap, inode));
1996 : }
1997 :
1998 0 : static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
1999 : {
2000 0 : *kiocb = (struct kiocb) {
2001 : .ki_filp = filp,
2002 0 : .ki_flags = filp->f_iocb_flags,
2003 0 : .ki_ioprio = get_current_ioprio(),
2004 : };
2005 0 : }
2006 :
2007 : static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
2008 : struct file *filp)
2009 : {
2010 : *kiocb = (struct kiocb) {
2011 : .ki_filp = filp,
2012 : .ki_flags = kiocb_src->ki_flags,
2013 : .ki_ioprio = kiocb_src->ki_ioprio,
2014 : .ki_pos = kiocb_src->ki_pos,
2015 : };
2016 : }
2017 :
2018 : /*
2019 : * Inode state bits. Protected by inode->i_lock
2020 : *
2021 : * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
2022 : * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
2023 : *
2024 : * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
2025 : * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
2026 : * various stages of removing an inode.
2027 : *
2028 : * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
2029 : *
2030 : * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
2031 : * fdatasync() (unless I_DIRTY_DATASYNC is also set).
2032 : * Timestamp updates are the usual cause.
2033 : * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
2034 : * these changes separately from I_DIRTY_SYNC so that we
2035 : * don't have to write inode on fdatasync() when only
2036 : * e.g. the timestamps have changed.
2037 : * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
2038 : * I_DIRTY_TIME The inode itself has dirty timestamps, and the
2039 : * lazytime mount option is enabled. We keep track of this
2040 : * separately from I_DIRTY_SYNC in order to implement
2041 : * lazytime. This gets cleared if I_DIRTY_INODE
2042 : * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. But
2043 : * I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already
2044 : * in place because writeback might already be in progress
2045 : * and we don't want to lose the time update
2046 : * I_NEW Serves as both a mutex and completion notification.
2047 : * New inodes set I_NEW. If two processes both create
2048 : * the same inode, one of them will release its inode and
2049 : * wait for I_NEW to be released before returning.
2050 : * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
2051 : * also cause waiting on I_NEW, without I_NEW actually
2052 : * being set. find_inode() uses this to prevent returning
2053 : * nearly-dead inodes.
2054 : * I_WILL_FREE Must be set when calling write_inode_now() if i_count
2055 : * is zero. I_FREEING must be set when I_WILL_FREE is
2056 : * cleared.
2057 : * I_FREEING Set when inode is about to be freed but still has dirty
2058 : * pages or buffers attached or the inode itself is still
2059 : * dirty.
2060 : * I_CLEAR Added by clear_inode(). In this state the inode is
2061 : * clean and can be destroyed. Inode keeps I_FREEING.
2062 : *
2063 : * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
2064 : * prohibited for many purposes. iget() must wait for
2065 : * the inode to be completely released, then create it
2066 : * anew. Other functions will just ignore such inodes,
2067 : * if appropriate. I_NEW is used for waiting.
2068 : *
2069 : * I_SYNC Writeback of inode is running. The bit is set during
2070 : * data writeback, and cleared with a wakeup on the bit
2071 : * address once it is done. The bit is also used to pin
2072 : * the inode in memory for flusher thread.
2073 : *
2074 : * I_REFERENCED Marks the inode as recently references on the LRU list.
2075 : *
2076 : * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
2077 : *
2078 : * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
2079 : * synchronize competing switching instances and to tell
2080 : * wb stat updates to grab the i_pages lock. See
2081 : * inode_switch_wbs_work_fn() for details.
2082 : *
2083 : * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
2084 : * and work dirs among overlayfs mounts.
2085 : *
2086 : * I_CREATING New object's inode in the middle of setting up.
2087 : *
2088 : * I_DONTCACHE Evict inode as soon as it is not used anymore.
2089 : *
2090 : * I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
2091 : * Used to detect that mark_inode_dirty() should not move
2092 : * inode between dirty lists.
2093 : *
2094 : * I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
2095 : *
2096 : * Q: What is the difference between I_WILL_FREE and I_FREEING?
2097 : */
2098 : #define I_DIRTY_SYNC (1 << 0)
2099 : #define I_DIRTY_DATASYNC (1 << 1)
2100 : #define I_DIRTY_PAGES (1 << 2)
2101 : #define __I_NEW 3
2102 : #define I_NEW (1 << __I_NEW)
2103 : #define I_WILL_FREE (1 << 4)
2104 : #define I_FREEING (1 << 5)
2105 : #define I_CLEAR (1 << 6)
2106 : #define __I_SYNC 7
2107 : #define I_SYNC (1 << __I_SYNC)
2108 : #define I_REFERENCED (1 << 8)
2109 : #define __I_DIO_WAKEUP 9
2110 : #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
2111 : #define I_LINKABLE (1 << 10)
2112 : #define I_DIRTY_TIME (1 << 11)
2113 : #define I_WB_SWITCH (1 << 13)
2114 : #define I_OVL_INUSE (1 << 14)
2115 : #define I_CREATING (1 << 15)
2116 : #define I_DONTCACHE (1 << 16)
2117 : #define I_SYNC_QUEUED (1 << 17)
2118 : #define I_PINNING_FSCACHE_WB (1 << 18)
2119 :
2120 : #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
2121 : #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
2122 : #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
2123 :
2124 : extern void __mark_inode_dirty(struct inode *, int);
2125 : static inline void mark_inode_dirty(struct inode *inode)
2126 : {
2127 0 : __mark_inode_dirty(inode, I_DIRTY);
2128 : }
2129 :
2130 : static inline void mark_inode_dirty_sync(struct inode *inode)
2131 : {
2132 0 : __mark_inode_dirty(inode, I_DIRTY_SYNC);
2133 : }
2134 :
2135 : /*
2136 : * Returns true if the given inode itself only has dirty timestamps (its pages
2137 : * may still be dirty) and isn't currently being allocated or freed.
2138 : * Filesystems should call this if when writing an inode when lazytime is
2139 : * enabled, they want to opportunistically write the timestamps of other inodes
2140 : * located very nearby on-disk, e.g. in the same inode block. This returns true
2141 : * if the given inode is in need of such an opportunistic update. Requires
2142 : * i_lock, or at least later re-checking under i_lock.
2143 : */
2144 : static inline bool inode_is_dirtytime_only(struct inode *inode)
2145 : {
2146 : return (inode->i_state & (I_DIRTY_TIME | I_NEW |
2147 : I_FREEING | I_WILL_FREE)) == I_DIRTY_TIME;
2148 : }
2149 :
2150 : extern void inc_nlink(struct inode *inode);
2151 : extern void drop_nlink(struct inode *inode);
2152 : extern void clear_nlink(struct inode *inode);
2153 : extern void set_nlink(struct inode *inode, unsigned int nlink);
2154 :
2155 : static inline void inode_inc_link_count(struct inode *inode)
2156 : {
2157 : inc_nlink(inode);
2158 : mark_inode_dirty(inode);
2159 : }
2160 :
2161 : static inline void inode_dec_link_count(struct inode *inode)
2162 : {
2163 0 : drop_nlink(inode);
2164 0 : mark_inode_dirty(inode);
2165 : }
2166 :
2167 : enum file_time_flags {
2168 : S_ATIME = 1,
2169 : S_MTIME = 2,
2170 : S_CTIME = 4,
2171 : S_VERSION = 8,
2172 : };
2173 :
2174 : extern bool atime_needs_update(const struct path *, struct inode *);
2175 : extern void touch_atime(const struct path *);
2176 : int inode_update_time(struct inode *inode, struct timespec64 *time, int flags);
2177 :
2178 : static inline void file_accessed(struct file *file)
2179 : {
2180 0 : if (!(file->f_flags & O_NOATIME))
2181 0 : touch_atime(&file->f_path);
2182 : }
2183 :
2184 : extern int file_modified(struct file *file);
2185 : int kiocb_modified(struct kiocb *iocb);
2186 :
2187 : int sync_inode_metadata(struct inode *inode, int wait);
2188 :
2189 : struct file_system_type {
2190 : const char *name;
2191 : int fs_flags;
2192 : #define FS_REQUIRES_DEV 1
2193 : #define FS_BINARY_MOUNTDATA 2
2194 : #define FS_HAS_SUBTYPE 4
2195 : #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2196 : #define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
2197 : #define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
2198 : #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2199 : int (*init_fs_context)(struct fs_context *);
2200 : const struct fs_parameter_spec *parameters;
2201 : struct dentry *(*mount) (struct file_system_type *, int,
2202 : const char *, void *);
2203 : void (*kill_sb) (struct super_block *);
2204 : struct module *owner;
2205 : struct file_system_type * next;
2206 : struct hlist_head fs_supers;
2207 :
2208 : struct lock_class_key s_lock_key;
2209 : struct lock_class_key s_umount_key;
2210 : struct lock_class_key s_vfs_rename_key;
2211 : struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
2212 :
2213 : struct lock_class_key i_lock_key;
2214 : struct lock_class_key i_mutex_key;
2215 : struct lock_class_key invalidate_lock_key;
2216 : struct lock_class_key i_mutex_dir_key;
2217 : };
2218 :
2219 : #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2220 :
2221 : extern struct dentry *mount_bdev(struct file_system_type *fs_type,
2222 : int flags, const char *dev_name, void *data,
2223 : int (*fill_super)(struct super_block *, void *, int));
2224 : extern struct dentry *mount_single(struct file_system_type *fs_type,
2225 : int flags, void *data,
2226 : int (*fill_super)(struct super_block *, void *, int));
2227 : extern struct dentry *mount_nodev(struct file_system_type *fs_type,
2228 : int flags, void *data,
2229 : int (*fill_super)(struct super_block *, void *, int));
2230 : extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
2231 : void retire_super(struct super_block *sb);
2232 : void generic_shutdown_super(struct super_block *sb);
2233 : void kill_block_super(struct super_block *sb);
2234 : void kill_anon_super(struct super_block *sb);
2235 : void kill_litter_super(struct super_block *sb);
2236 : void deactivate_super(struct super_block *sb);
2237 : void deactivate_locked_super(struct super_block *sb);
2238 : int set_anon_super(struct super_block *s, void *data);
2239 : int set_anon_super_fc(struct super_block *s, struct fs_context *fc);
2240 : int get_anon_bdev(dev_t *);
2241 : void free_anon_bdev(dev_t);
2242 : struct super_block *sget_fc(struct fs_context *fc,
2243 : int (*test)(struct super_block *, struct fs_context *),
2244 : int (*set)(struct super_block *, struct fs_context *));
2245 : struct super_block *sget(struct file_system_type *type,
2246 : int (*test)(struct super_block *,void *),
2247 : int (*set)(struct super_block *,void *),
2248 : int flags, void *data);
2249 :
2250 : /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2251 : #define fops_get(fops) \
2252 : (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2253 : #define fops_put(fops) \
2254 : do { if (fops) module_put((fops)->owner); } while(0)
2255 : /*
2256 : * This one is to be used *ONLY* from ->open() instances.
2257 : * fops must be non-NULL, pinned down *and* module dependencies
2258 : * should be sufficient to pin the caller down as well.
2259 : */
2260 : #define replace_fops(f, fops) \
2261 : do { \
2262 : struct file *__file = (f); \
2263 : fops_put(__file->f_op); \
2264 : BUG_ON(!(__file->f_op = (fops))); \
2265 : } while(0)
2266 :
2267 : extern int register_filesystem(struct file_system_type *);
2268 : extern int unregister_filesystem(struct file_system_type *);
2269 : extern int vfs_statfs(const struct path *, struct kstatfs *);
2270 : extern int user_statfs(const char __user *, struct kstatfs *);
2271 : extern int fd_statfs(int, struct kstatfs *);
2272 : extern int freeze_super(struct super_block *super);
2273 : extern int thaw_super(struct super_block *super);
2274 : extern __printf(2, 3)
2275 : int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
2276 : extern int super_setup_bdi(struct super_block *sb);
2277 :
2278 : extern int current_umask(void);
2279 :
2280 : extern void ihold(struct inode * inode);
2281 : extern void iput(struct inode *);
2282 : extern int generic_update_time(struct inode *, struct timespec64 *, int);
2283 :
2284 : /* /sys/fs */
2285 : extern struct kobject *fs_kobj;
2286 :
2287 : #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2288 :
2289 : /* fs/open.c */
2290 : struct audit_names;
2291 : struct filename {
2292 : const char *name; /* pointer to actual string */
2293 : const __user char *uptr; /* original userland pointer */
2294 : int refcnt;
2295 : struct audit_names *aname;
2296 : const char iname[];
2297 : };
2298 : static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
2299 :
2300 : static inline struct mnt_idmap *file_mnt_idmap(struct file *file)
2301 : {
2302 0 : return mnt_idmap(file->f_path.mnt);
2303 : }
2304 :
2305 : /**
2306 : * is_idmapped_mnt - check whether a mount is mapped
2307 : * @mnt: the mount to check
2308 : *
2309 : * If @mnt has an non @nop_mnt_idmap attached to it then @mnt is mapped.
2310 : *
2311 : * Return: true if mount is mapped, false if not.
2312 : */
2313 : static inline bool is_idmapped_mnt(const struct vfsmount *mnt)
2314 : {
2315 0 : return mnt_idmap(mnt) != &nop_mnt_idmap;
2316 : }
2317 :
2318 : extern long vfs_truncate(const struct path *, loff_t);
2319 : int do_truncate(struct mnt_idmap *, struct dentry *, loff_t start,
2320 : unsigned int time_attrs, struct file *filp);
2321 : extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2322 : loff_t len);
2323 : extern long do_sys_open(int dfd, const char __user *filename, int flags,
2324 : umode_t mode);
2325 : extern struct file *file_open_name(struct filename *, int, umode_t);
2326 : extern struct file *filp_open(const char *, int, umode_t);
2327 : extern struct file *file_open_root(const struct path *,
2328 : const char *, int, umode_t);
2329 : static inline struct file *file_open_root_mnt(struct vfsmount *mnt,
2330 : const char *name, int flags, umode_t mode)
2331 : {
2332 0 : return file_open_root(&(struct path){.mnt = mnt, .dentry = mnt->mnt_root},
2333 : name, flags, mode);
2334 : }
2335 : extern struct file * dentry_open(const struct path *, int, const struct cred *);
2336 : extern struct file *dentry_create(const struct path *path, int flags,
2337 : umode_t mode, const struct cred *cred);
2338 : extern struct file * open_with_fake_path(const struct path *, int,
2339 : struct inode*, const struct cred *);
2340 : static inline struct file *file_clone_open(struct file *file)
2341 : {
2342 0 : return dentry_open(&file->f_path, file->f_flags, file->f_cred);
2343 : }
2344 : extern int filp_close(struct file *, fl_owner_t id);
2345 :
2346 : extern struct filename *getname_flags(const char __user *, int, int *);
2347 : extern struct filename *getname_uflags(const char __user *, int);
2348 : extern struct filename *getname(const char __user *);
2349 : extern struct filename *getname_kernel(const char *);
2350 : extern void putname(struct filename *name);
2351 :
2352 : extern int finish_open(struct file *file, struct dentry *dentry,
2353 : int (*open)(struct inode *, struct file *));
2354 : extern int finish_no_open(struct file *file, struct dentry *dentry);
2355 :
2356 : /* Helper for the simple case when original dentry is used */
2357 : static inline int finish_open_simple(struct file *file, int error)
2358 : {
2359 : if (error)
2360 : return error;
2361 :
2362 0 : return finish_open(file, file->f_path.dentry, NULL);
2363 : }
2364 :
2365 : /* fs/dcache.c */
2366 : extern void __init vfs_caches_init_early(void);
2367 : extern void __init vfs_caches_init(void);
2368 :
2369 : extern struct kmem_cache *names_cachep;
2370 :
2371 : #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2372 : #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2373 :
2374 : extern struct super_block *blockdev_superblock;
2375 : static inline bool sb_is_blkdev_sb(struct super_block *sb)
2376 : {
2377 0 : return IS_ENABLED(CONFIG_BLOCK) && sb == blockdev_superblock;
2378 : }
2379 :
2380 : void emergency_thaw_all(void);
2381 : extern int sync_filesystem(struct super_block *);
2382 : extern const struct file_operations def_blk_fops;
2383 : extern const struct file_operations def_chr_fops;
2384 :
2385 : /* fs/char_dev.c */
2386 : #define CHRDEV_MAJOR_MAX 512
2387 : /* Marks the bottom of the first segment of free char majors */
2388 : #define CHRDEV_MAJOR_DYN_END 234
2389 : /* Marks the top and bottom of the second segment of free char majors */
2390 : #define CHRDEV_MAJOR_DYN_EXT_START 511
2391 : #define CHRDEV_MAJOR_DYN_EXT_END 384
2392 :
2393 : extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2394 : extern int register_chrdev_region(dev_t, unsigned, const char *);
2395 : extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2396 : unsigned int count, const char *name,
2397 : const struct file_operations *fops);
2398 : extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2399 : unsigned int count, const char *name);
2400 : extern void unregister_chrdev_region(dev_t, unsigned);
2401 : extern void chrdev_show(struct seq_file *,off_t);
2402 :
2403 : static inline int register_chrdev(unsigned int major, const char *name,
2404 : const struct file_operations *fops)
2405 : {
2406 3 : return __register_chrdev(major, 0, 256, name, fops);
2407 : }
2408 :
2409 : static inline void unregister_chrdev(unsigned int major, const char *name)
2410 : {
2411 0 : __unregister_chrdev(major, 0, 256, name);
2412 : }
2413 :
2414 : extern void init_special_inode(struct inode *, umode_t, dev_t);
2415 :
2416 : /* Invalid inode operations -- fs/bad_inode.c */
2417 : extern void make_bad_inode(struct inode *);
2418 : extern bool is_bad_inode(struct inode *);
2419 :
2420 : extern int __must_check file_fdatawait_range(struct file *file, loff_t lstart,
2421 : loff_t lend);
2422 : extern int __must_check file_check_and_advance_wb_err(struct file *file);
2423 : extern int __must_check file_write_and_wait_range(struct file *file,
2424 : loff_t start, loff_t end);
2425 :
2426 : static inline int file_write_and_wait(struct file *file)
2427 : {
2428 : return file_write_and_wait_range(file, 0, LLONG_MAX);
2429 : }
2430 :
2431 : extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2432 : int datasync);
2433 : extern int vfs_fsync(struct file *file, int datasync);
2434 :
2435 : extern int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
2436 : unsigned int flags);
2437 :
2438 : static inline bool iocb_is_dsync(const struct kiocb *iocb)
2439 : {
2440 0 : return (iocb->ki_flags & IOCB_DSYNC) ||
2441 0 : IS_SYNC(iocb->ki_filp->f_mapping->host);
2442 : }
2443 :
2444 : /*
2445 : * Sync the bytes written if this was a synchronous write. Expect ki_pos
2446 : * to already be updated for the write, and will return either the amount
2447 : * of bytes passed in, or an error if syncing the file failed.
2448 : */
2449 0 : static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
2450 : {
2451 0 : if (iocb_is_dsync(iocb)) {
2452 0 : int ret = vfs_fsync_range(iocb->ki_filp,
2453 0 : iocb->ki_pos - count, iocb->ki_pos - 1,
2454 0 : (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
2455 0 : if (ret)
2456 0 : return ret;
2457 : }
2458 :
2459 : return count;
2460 : }
2461 :
2462 : extern void emergency_sync(void);
2463 : extern void emergency_remount(void);
2464 :
2465 : #ifdef CONFIG_BLOCK
2466 : extern int bmap(struct inode *inode, sector_t *block);
2467 : #else
2468 : static inline int bmap(struct inode *inode, sector_t *block)
2469 : {
2470 : return -EINVAL;
2471 : }
2472 : #endif
2473 :
2474 : int notify_change(struct mnt_idmap *, struct dentry *,
2475 : struct iattr *, struct inode **);
2476 : int inode_permission(struct mnt_idmap *, struct inode *, int);
2477 : int generic_permission(struct mnt_idmap *, struct inode *, int);
2478 : static inline int file_permission(struct file *file, int mask)
2479 : {
2480 0 : return inode_permission(file_mnt_idmap(file),
2481 : file_inode(file), mask);
2482 : }
2483 : static inline int path_permission(const struct path *path, int mask)
2484 : {
2485 0 : return inode_permission(mnt_idmap(path->mnt),
2486 0 : d_inode(path->dentry), mask);
2487 : }
2488 : int __check_sticky(struct mnt_idmap *idmap, struct inode *dir,
2489 : struct inode *inode);
2490 :
2491 : static inline bool execute_ok(struct inode *inode)
2492 : {
2493 : return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2494 : }
2495 :
2496 : static inline bool inode_wrong_type(const struct inode *inode, umode_t mode)
2497 : {
2498 : return (inode->i_mode ^ mode) & S_IFMT;
2499 : }
2500 :
2501 : static inline void file_start_write(struct file *file)
2502 : {
2503 0 : if (!S_ISREG(file_inode(file)->i_mode))
2504 : return;
2505 0 : sb_start_write(file_inode(file)->i_sb);
2506 : }
2507 :
2508 : static inline bool file_start_write_trylock(struct file *file)
2509 : {
2510 : if (!S_ISREG(file_inode(file)->i_mode))
2511 : return true;
2512 : return sb_start_write_trylock(file_inode(file)->i_sb);
2513 : }
2514 :
2515 : static inline void file_end_write(struct file *file)
2516 : {
2517 0 : if (!S_ISREG(file_inode(file)->i_mode))
2518 : return;
2519 0 : __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2520 : }
2521 :
2522 : /*
2523 : * This is used for regular files where some users -- especially the
2524 : * currently executed binary in a process, previously handled via
2525 : * VM_DENYWRITE -- cannot handle concurrent write (and maybe mmap
2526 : * read-write shared) accesses.
2527 : *
2528 : * get_write_access() gets write permission for a file.
2529 : * put_write_access() releases this write permission.
2530 : * deny_write_access() denies write access to a file.
2531 : * allow_write_access() re-enables write access to a file.
2532 : *
2533 : * The i_writecount field of an inode can have the following values:
2534 : * 0: no write access, no denied write access
2535 : * < 0: (-i_writecount) users that denied write access to the file.
2536 : * > 0: (i_writecount) users that have write access to the file.
2537 : *
2538 : * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2539 : * except for the cases where we don't hold i_writecount yet. Then we need to
2540 : * use {get,deny}_write_access() - these functions check the sign and refuse
2541 : * to do the change if sign is wrong.
2542 : */
2543 : static inline int get_write_access(struct inode *inode)
2544 : {
2545 0 : return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2546 : }
2547 : static inline int deny_write_access(struct file *file)
2548 : {
2549 0 : struct inode *inode = file_inode(file);
2550 0 : return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2551 : }
2552 : static inline void put_write_access(struct inode * inode)
2553 : {
2554 0 : atomic_dec(&inode->i_writecount);
2555 : }
2556 : static inline void allow_write_access(struct file *file)
2557 : {
2558 0 : if (file)
2559 0 : atomic_inc(&file_inode(file)->i_writecount);
2560 : }
2561 : static inline bool inode_is_open_for_write(const struct inode *inode)
2562 : {
2563 0 : return atomic_read(&inode->i_writecount) > 0;
2564 : }
2565 :
2566 : #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
2567 0 : static inline void i_readcount_dec(struct inode *inode)
2568 : {
2569 0 : BUG_ON(!atomic_read(&inode->i_readcount));
2570 0 : atomic_dec(&inode->i_readcount);
2571 0 : }
2572 : static inline void i_readcount_inc(struct inode *inode)
2573 : {
2574 0 : atomic_inc(&inode->i_readcount);
2575 : }
2576 : #else
2577 : static inline void i_readcount_dec(struct inode *inode)
2578 : {
2579 : return;
2580 : }
2581 : static inline void i_readcount_inc(struct inode *inode)
2582 : {
2583 : return;
2584 : }
2585 : #endif
2586 : extern int do_pipe_flags(int *, int);
2587 :
2588 : extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
2589 : ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos);
2590 : extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *);
2591 : extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *);
2592 : extern struct file * open_exec(const char *);
2593 :
2594 : /* fs/dcache.c -- generic fs support functions */
2595 : extern bool is_subdir(struct dentry *, struct dentry *);
2596 : extern bool path_is_under(const struct path *, const struct path *);
2597 :
2598 : extern char *file_path(struct file *, char *, int);
2599 :
2600 : #include <linux/err.h>
2601 :
2602 : /* needed for stackable file system support */
2603 : extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2604 :
2605 : extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2606 :
2607 : extern int inode_init_always(struct super_block *, struct inode *);
2608 : extern void inode_init_once(struct inode *);
2609 : extern void address_space_init_once(struct address_space *mapping);
2610 : extern struct inode * igrab(struct inode *);
2611 : extern ino_t iunique(struct super_block *, ino_t);
2612 : extern int inode_needs_sync(struct inode *inode);
2613 : extern int generic_delete_inode(struct inode *inode);
2614 : static inline int generic_drop_inode(struct inode *inode)
2615 : {
2616 68 : return !inode->i_nlink || inode_unhashed(inode);
2617 : }
2618 : extern void d_mark_dontcache(struct inode *inode);
2619 :
2620 : extern struct inode *ilookup5_nowait(struct super_block *sb,
2621 : unsigned long hashval, int (*test)(struct inode *, void *),
2622 : void *data);
2623 : extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2624 : int (*test)(struct inode *, void *), void *data);
2625 : extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2626 :
2627 : extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
2628 : int (*test)(struct inode *, void *),
2629 : int (*set)(struct inode *, void *),
2630 : void *data);
2631 : extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2632 : extern struct inode * iget_locked(struct super_block *, unsigned long);
2633 : extern struct inode *find_inode_nowait(struct super_block *,
2634 : unsigned long,
2635 : int (*match)(struct inode *,
2636 : unsigned long, void *),
2637 : void *data);
2638 : extern struct inode *find_inode_rcu(struct super_block *, unsigned long,
2639 : int (*)(struct inode *, void *), void *);
2640 : extern struct inode *find_inode_by_ino_rcu(struct super_block *, unsigned long);
2641 : extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2642 : extern int insert_inode_locked(struct inode *);
2643 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
2644 : extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2645 : #else
2646 : static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2647 : #endif
2648 : extern void unlock_new_inode(struct inode *);
2649 : extern void discard_new_inode(struct inode *);
2650 : extern unsigned int get_next_ino(void);
2651 : extern void evict_inodes(struct super_block *sb);
2652 : void dump_mapping(const struct address_space *);
2653 :
2654 : /*
2655 : * Userspace may rely on the the inode number being non-zero. For example, glibc
2656 : * simply ignores files with zero i_ino in unlink() and other places.
2657 : *
2658 : * As an additional complication, if userspace was compiled with
2659 : * _FILE_OFFSET_BITS=32 on a 64-bit kernel we'll only end up reading out the
2660 : * lower 32 bits, so we need to check that those aren't zero explicitly. With
2661 : * _FILE_OFFSET_BITS=64, this may cause some harmless false-negatives, but
2662 : * better safe than sorry.
2663 : */
2664 : static inline bool is_zero_ino(ino_t ino)
2665 : {
2666 1 : return (u32)ino == 0;
2667 : }
2668 :
2669 : extern void __iget(struct inode * inode);
2670 : extern void iget_failed(struct inode *);
2671 : extern void clear_inode(struct inode *);
2672 : extern void __destroy_inode(struct inode *);
2673 : extern struct inode *new_inode_pseudo(struct super_block *sb);
2674 : extern struct inode *new_inode(struct super_block *sb);
2675 : extern void free_inode_nonrcu(struct inode *inode);
2676 : extern int setattr_should_drop_suidgid(struct mnt_idmap *, struct inode *);
2677 : extern int file_remove_privs(struct file *);
2678 :
2679 : /*
2680 : * This must be used for allocating filesystems specific inodes to set
2681 : * up the inode reclaim context correctly.
2682 : */
2683 : static inline void *
2684 : alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp)
2685 : {
2686 51 : return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp);
2687 : }
2688 :
2689 : extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2690 : static inline void insert_inode_hash(struct inode *inode)
2691 : {
2692 0 : __insert_inode_hash(inode, inode->i_ino);
2693 : }
2694 :
2695 : extern void __remove_inode_hash(struct inode *);
2696 : static inline void remove_inode_hash(struct inode *inode)
2697 : {
2698 34 : if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
2699 0 : __remove_inode_hash(inode);
2700 : }
2701 :
2702 : extern void inode_sb_list_add(struct inode *inode);
2703 : extern void inode_add_lru(struct inode *inode);
2704 :
2705 : extern int sb_set_blocksize(struct super_block *, int);
2706 : extern int sb_min_blocksize(struct super_block *, int);
2707 :
2708 : extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2709 : extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2710 : extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
2711 : int generic_write_checks_count(struct kiocb *iocb, loff_t *count);
2712 : extern int generic_write_check_limits(struct file *file, loff_t pos,
2713 : loff_t *count);
2714 : extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);
2715 : ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *to,
2716 : ssize_t already_read);
2717 : extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2718 : extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
2719 : extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
2720 : extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
2721 : ssize_t generic_perform_write(struct kiocb *, struct iov_iter *);
2722 :
2723 : ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
2724 : rwf_t flags);
2725 : ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
2726 : rwf_t flags);
2727 : ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb,
2728 : struct iov_iter *iter);
2729 : ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb,
2730 : struct iov_iter *iter);
2731 :
2732 : /* fs/splice.c */
2733 : ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
2734 : struct pipe_inode_info *pipe,
2735 : size_t len, unsigned int flags);
2736 : ssize_t direct_splice_read(struct file *in, loff_t *ppos,
2737 : struct pipe_inode_info *pipe,
2738 : size_t len, unsigned int flags);
2739 : extern ssize_t generic_file_splice_read(struct file *, loff_t *,
2740 : struct pipe_inode_info *, size_t, unsigned int);
2741 : extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
2742 : struct file *, loff_t *, size_t, unsigned int);
2743 : extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2744 : struct file *out, loff_t *, size_t len, unsigned int flags);
2745 : extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
2746 : loff_t *opos, size_t len, unsigned int flags);
2747 :
2748 :
2749 : extern void
2750 : file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2751 : extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
2752 : #define no_llseek NULL
2753 : extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
2754 : extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
2755 : extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
2756 : int whence, loff_t maxsize, loff_t eof);
2757 : extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
2758 : int whence, loff_t size);
2759 : extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
2760 : extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
2761 : int rw_verify_area(int, struct file *, const loff_t *, size_t);
2762 : extern int generic_file_open(struct inode * inode, struct file * filp);
2763 : extern int nonseekable_open(struct inode * inode, struct file * filp);
2764 : extern int stream_open(struct inode * inode, struct file * filp);
2765 :
2766 : #ifdef CONFIG_BLOCK
2767 : typedef void (dio_submit_t)(struct bio *bio, struct inode *inode,
2768 : loff_t file_offset);
2769 :
2770 : enum {
2771 : /* need locking between buffered and direct access */
2772 : DIO_LOCKING = 0x01,
2773 :
2774 : /* filesystem does not support filling holes */
2775 : DIO_SKIP_HOLES = 0x02,
2776 : };
2777 :
2778 : ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
2779 : struct block_device *bdev, struct iov_iter *iter,
2780 : get_block_t get_block,
2781 : dio_iodone_t end_io, dio_submit_t submit_io,
2782 : int flags);
2783 :
2784 : static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
2785 : struct inode *inode,
2786 : struct iov_iter *iter,
2787 : get_block_t get_block)
2788 : {
2789 : return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
2790 : get_block, NULL, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
2791 : }
2792 : #endif
2793 :
2794 : void inode_dio_wait(struct inode *inode);
2795 :
2796 : /**
2797 : * inode_dio_begin - signal start of a direct I/O requests
2798 : * @inode: inode the direct I/O happens on
2799 : *
2800 : * This is called once we've finished processing a direct I/O request,
2801 : * and is used to wake up callers waiting for direct I/O to be quiesced.
2802 : */
2803 : static inline void inode_dio_begin(struct inode *inode)
2804 : {
2805 : atomic_inc(&inode->i_dio_count);
2806 : }
2807 :
2808 : /**
2809 : * inode_dio_end - signal finish of a direct I/O requests
2810 : * @inode: inode the direct I/O happens on
2811 : *
2812 : * This is called once we've finished processing a direct I/O request,
2813 : * and is used to wake up callers waiting for direct I/O to be quiesced.
2814 : */
2815 : static inline void inode_dio_end(struct inode *inode)
2816 : {
2817 : if (atomic_dec_and_test(&inode->i_dio_count))
2818 : wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
2819 : }
2820 :
2821 : /*
2822 : * Warn about a page cache invalidation failure diring a direct I/O write.
2823 : */
2824 : void dio_warn_stale_pagecache(struct file *filp);
2825 :
2826 : extern void inode_set_flags(struct inode *inode, unsigned int flags,
2827 : unsigned int mask);
2828 :
2829 : extern const struct file_operations generic_ro_fops;
2830 :
2831 : #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2832 :
2833 : extern int readlink_copy(char __user *, int, const char *);
2834 : extern int page_readlink(struct dentry *, char __user *, int);
2835 : extern const char *page_get_link(struct dentry *, struct inode *,
2836 : struct delayed_call *);
2837 : extern void page_put_link(void *);
2838 : extern int page_symlink(struct inode *inode, const char *symname, int len);
2839 : extern const struct inode_operations page_symlink_inode_operations;
2840 : extern void kfree_link(void *);
2841 : void generic_fillattr(struct mnt_idmap *, struct inode *, struct kstat *);
2842 : void generic_fill_statx_attr(struct inode *inode, struct kstat *stat);
2843 : extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
2844 : extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
2845 : void __inode_add_bytes(struct inode *inode, loff_t bytes);
2846 : void inode_add_bytes(struct inode *inode, loff_t bytes);
2847 : void __inode_sub_bytes(struct inode *inode, loff_t bytes);
2848 : void inode_sub_bytes(struct inode *inode, loff_t bytes);
2849 : static inline loff_t __inode_get_bytes(struct inode *inode)
2850 : {
2851 0 : return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
2852 : }
2853 : loff_t inode_get_bytes(struct inode *inode);
2854 : void inode_set_bytes(struct inode *inode, loff_t bytes);
2855 : const char *simple_get_link(struct dentry *, struct inode *,
2856 : struct delayed_call *);
2857 : extern const struct inode_operations simple_symlink_inode_operations;
2858 :
2859 : extern int iterate_dir(struct file *, struct dir_context *);
2860 :
2861 : int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
2862 : int flags);
2863 : int vfs_fstat(int fd, struct kstat *stat);
2864 :
2865 : static inline int vfs_stat(const char __user *filename, struct kstat *stat)
2866 : {
2867 0 : return vfs_fstatat(AT_FDCWD, filename, stat, 0);
2868 : }
2869 : static inline int vfs_lstat(const char __user *name, struct kstat *stat)
2870 : {
2871 0 : return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
2872 : }
2873 :
2874 : extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
2875 : extern int vfs_readlink(struct dentry *, char __user *, int);
2876 :
2877 : extern struct file_system_type *get_filesystem(struct file_system_type *fs);
2878 : extern void put_filesystem(struct file_system_type *fs);
2879 : extern struct file_system_type *get_fs_type(const char *name);
2880 : extern struct super_block *get_super(struct block_device *);
2881 : extern struct super_block *get_active_super(struct block_device *bdev);
2882 : extern void drop_super(struct super_block *sb);
2883 : extern void drop_super_exclusive(struct super_block *sb);
2884 : extern void iterate_supers(void (*)(struct super_block *, void *), void *);
2885 : extern void iterate_supers_type(struct file_system_type *,
2886 : void (*)(struct super_block *, void *), void *);
2887 :
2888 : extern int dcache_dir_open(struct inode *, struct file *);
2889 : extern int dcache_dir_close(struct inode *, struct file *);
2890 : extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2891 : extern int dcache_readdir(struct file *, struct dir_context *);
2892 : extern int simple_setattr(struct mnt_idmap *, struct dentry *,
2893 : struct iattr *);
2894 : extern int simple_getattr(struct mnt_idmap *, const struct path *,
2895 : struct kstat *, u32, unsigned int);
2896 : extern int simple_statfs(struct dentry *, struct kstatfs *);
2897 : extern int simple_open(struct inode *inode, struct file *file);
2898 : extern int simple_link(struct dentry *, struct inode *, struct dentry *);
2899 : extern int simple_unlink(struct inode *, struct dentry *);
2900 : extern int simple_rmdir(struct inode *, struct dentry *);
2901 : extern int simple_rename_exchange(struct inode *old_dir, struct dentry *old_dentry,
2902 : struct inode *new_dir, struct dentry *new_dentry);
2903 : extern int simple_rename(struct mnt_idmap *, struct inode *,
2904 : struct dentry *, struct inode *, struct dentry *,
2905 : unsigned int);
2906 : extern void simple_recursive_removal(struct dentry *,
2907 : void (*callback)(struct dentry *));
2908 : extern int noop_fsync(struct file *, loff_t, loff_t, int);
2909 : extern ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
2910 : extern int simple_empty(struct dentry *);
2911 : extern int simple_write_begin(struct file *file, struct address_space *mapping,
2912 : loff_t pos, unsigned len,
2913 : struct page **pagep, void **fsdata);
2914 : extern const struct address_space_operations ram_aops;
2915 : extern int always_delete_dentry(const struct dentry *);
2916 : extern struct inode *alloc_anon_inode(struct super_block *);
2917 : extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
2918 : extern const struct dentry_operations simple_dentry_operations;
2919 :
2920 : extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
2921 : extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2922 : extern const struct file_operations simple_dir_operations;
2923 : extern const struct inode_operations simple_dir_inode_operations;
2924 : extern void make_empty_dir_inode(struct inode *inode);
2925 : extern bool is_empty_dir_inode(struct inode *inode);
2926 : struct tree_descr { const char *name; const struct file_operations *ops; int mode; };
2927 : struct dentry *d_alloc_name(struct dentry *, const char *);
2928 : extern int simple_fill_super(struct super_block *, unsigned long,
2929 : const struct tree_descr *);
2930 : extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2931 : extern void simple_release_fs(struct vfsmount **mount, int *count);
2932 :
2933 : extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2934 : loff_t *ppos, const void *from, size_t available);
2935 : extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
2936 : const void __user *from, size_t count);
2937 :
2938 : extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
2939 : extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
2940 :
2941 : extern int generic_check_addressable(unsigned, u64);
2942 :
2943 : extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
2944 :
2945 : int may_setattr(struct mnt_idmap *idmap, struct inode *inode,
2946 : unsigned int ia_valid);
2947 : int setattr_prepare(struct mnt_idmap *, struct dentry *, struct iattr *);
2948 : extern int inode_newsize_ok(const struct inode *, loff_t offset);
2949 : void setattr_copy(struct mnt_idmap *, struct inode *inode,
2950 : const struct iattr *attr);
2951 :
2952 : extern int file_update_time(struct file *file);
2953 :
2954 : static inline bool vma_is_dax(const struct vm_area_struct *vma)
2955 : {
2956 : return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
2957 : }
2958 :
2959 : static inline bool vma_is_fsdax(struct vm_area_struct *vma)
2960 : {
2961 : struct inode *inode;
2962 :
2963 : if (!IS_ENABLED(CONFIG_FS_DAX) || !vma->vm_file)
2964 : return false;
2965 : if (!vma_is_dax(vma))
2966 : return false;
2967 : inode = file_inode(vma->vm_file);
2968 : if (S_ISCHR(inode->i_mode))
2969 : return false; /* device-dax */
2970 : return true;
2971 : }
2972 :
2973 : static inline int iocb_flags(struct file *file)
2974 : {
2975 0 : int res = 0;
2976 0 : if (file->f_flags & O_APPEND)
2977 0 : res |= IOCB_APPEND;
2978 0 : if (file->f_flags & O_DIRECT)
2979 0 : res |= IOCB_DIRECT;
2980 0 : if (file->f_flags & O_DSYNC)
2981 0 : res |= IOCB_DSYNC;
2982 0 : if (file->f_flags & __O_SYNC)
2983 0 : res |= IOCB_SYNC;
2984 : return res;
2985 : }
2986 :
2987 0 : static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
2988 : {
2989 0 : int kiocb_flags = 0;
2990 :
2991 : /* make sure there's no overlap between RWF and private IOCB flags */
2992 : BUILD_BUG_ON((__force int) RWF_SUPPORTED & IOCB_EVENTFD);
2993 :
2994 0 : if (!flags)
2995 : return 0;
2996 0 : if (unlikely(flags & ~RWF_SUPPORTED))
2997 : return -EOPNOTSUPP;
2998 :
2999 0 : if (flags & RWF_NOWAIT) {
3000 0 : if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
3001 : return -EOPNOTSUPP;
3002 : kiocb_flags |= IOCB_NOIO;
3003 : }
3004 0 : kiocb_flags |= (__force int) (flags & RWF_SUPPORTED);
3005 0 : if (flags & RWF_SYNC)
3006 0 : kiocb_flags |= IOCB_DSYNC;
3007 :
3008 0 : ki->ki_flags |= kiocb_flags;
3009 : return 0;
3010 : }
3011 :
3012 : static inline ino_t parent_ino(struct dentry *dentry)
3013 : {
3014 : ino_t res;
3015 :
3016 : /*
3017 : * Don't strictly need d_lock here? If the parent ino could change
3018 : * then surely we'd have a deeper race in the caller?
3019 : */
3020 0 : spin_lock(&dentry->d_lock);
3021 0 : res = dentry->d_parent->d_inode->i_ino;
3022 0 : spin_unlock(&dentry->d_lock);
3023 : return res;
3024 : }
3025 :
3026 : /* Transaction based IO helpers */
3027 :
3028 : /*
3029 : * An argresp is stored in an allocated page and holds the
3030 : * size of the argument or response, along with its content
3031 : */
3032 : struct simple_transaction_argresp {
3033 : ssize_t size;
3034 : char data[];
3035 : };
3036 :
3037 : #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3038 :
3039 : char *simple_transaction_get(struct file *file, const char __user *buf,
3040 : size_t size);
3041 : ssize_t simple_transaction_read(struct file *file, char __user *buf,
3042 : size_t size, loff_t *pos);
3043 : int simple_transaction_release(struct inode *inode, struct file *file);
3044 :
3045 : void simple_transaction_set(struct file *file, size_t n);
3046 :
3047 : /*
3048 : * simple attribute files
3049 : *
3050 : * These attributes behave similar to those in sysfs:
3051 : *
3052 : * Writing to an attribute immediately sets a value, an open file can be
3053 : * written to multiple times.
3054 : *
3055 : * Reading from an attribute creates a buffer from the value that might get
3056 : * read with multiple read calls. When the attribute has been read
3057 : * completely, no further read calls are possible until the file is opened
3058 : * again.
3059 : *
3060 : * All attributes contain a text representation of a numeric value
3061 : * that are accessed with the get() and set() functions.
3062 : */
3063 : #define DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, __is_signed) \
3064 : static int __fops ## _open(struct inode *inode, struct file *file) \
3065 : { \
3066 : __simple_attr_check_format(__fmt, 0ull); \
3067 : return simple_attr_open(inode, file, __get, __set, __fmt); \
3068 : } \
3069 : static const struct file_operations __fops = { \
3070 : .owner = THIS_MODULE, \
3071 : .open = __fops ## _open, \
3072 : .release = simple_attr_release, \
3073 : .read = simple_attr_read, \
3074 : .write = (__is_signed) ? simple_attr_write_signed : simple_attr_write, \
3075 : .llseek = generic_file_llseek, \
3076 : }
3077 :
3078 : #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3079 : DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, false)
3080 :
3081 : #define DEFINE_SIMPLE_ATTRIBUTE_SIGNED(__fops, __get, __set, __fmt) \
3082 : DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, true)
3083 :
3084 : static inline __printf(1, 2)
3085 : void __simple_attr_check_format(const char *fmt, ...)
3086 : {
3087 : /* don't do anything, just let the compiler check the arguments; */
3088 : }
3089 :
3090 : int simple_attr_open(struct inode *inode, struct file *file,
3091 : int (*get)(void *, u64 *), int (*set)(void *, u64),
3092 : const char *fmt);
3093 : int simple_attr_release(struct inode *inode, struct file *file);
3094 : ssize_t simple_attr_read(struct file *file, char __user *buf,
3095 : size_t len, loff_t *ppos);
3096 : ssize_t simple_attr_write(struct file *file, const char __user *buf,
3097 : size_t len, loff_t *ppos);
3098 : ssize_t simple_attr_write_signed(struct file *file, const char __user *buf,
3099 : size_t len, loff_t *ppos);
3100 :
3101 : struct ctl_table;
3102 : int __init list_bdev_fs_names(char *buf, size_t size);
3103 :
3104 : #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3105 : #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3106 :
3107 : #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3108 : #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3109 : (flag & __FMODE_NONOTIFY)))
3110 :
3111 : static inline bool is_sxid(umode_t mode)
3112 : {
3113 : return mode & (S_ISUID | S_ISGID);
3114 : }
3115 :
3116 : static inline int check_sticky(struct mnt_idmap *idmap,
3117 : struct inode *dir, struct inode *inode)
3118 : {
3119 0 : if (!(dir->i_mode & S_ISVTX))
3120 : return 0;
3121 :
3122 0 : return __check_sticky(idmap, dir, inode);
3123 : }
3124 :
3125 : static inline void inode_has_no_xattr(struct inode *inode)
3126 : {
3127 0 : if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & SB_NOSEC))
3128 0 : inode->i_flags |= S_NOSEC;
3129 : }
3130 :
3131 : static inline bool is_root_inode(struct inode *inode)
3132 : {
3133 : return inode == inode->i_sb->s_root->d_inode;
3134 : }
3135 :
3136 : static inline bool dir_emit(struct dir_context *ctx,
3137 : const char *name, int namelen,
3138 : u64 ino, unsigned type)
3139 : {
3140 0 : return ctx->actor(ctx, name, namelen, ctx->pos, ino, type);
3141 : }
3142 : static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
3143 : {
3144 0 : return ctx->actor(ctx, ".", 1, ctx->pos,
3145 0 : file->f_path.dentry->d_inode->i_ino, DT_DIR);
3146 : }
3147 : static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
3148 : {
3149 0 : return ctx->actor(ctx, "..", 2, ctx->pos,
3150 0 : parent_ino(file->f_path.dentry), DT_DIR);
3151 : }
3152 0 : static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
3153 : {
3154 0 : if (ctx->pos == 0) {
3155 0 : if (!dir_emit_dot(file, ctx))
3156 : return false;
3157 0 : ctx->pos = 1;
3158 : }
3159 0 : if (ctx->pos == 1) {
3160 0 : if (!dir_emit_dotdot(file, ctx))
3161 : return false;
3162 0 : ctx->pos = 2;
3163 : }
3164 : return true;
3165 : }
3166 : static inline bool dir_relax(struct inode *inode)
3167 : {
3168 : inode_unlock(inode);
3169 : inode_lock(inode);
3170 : return !IS_DEADDIR(inode);
3171 : }
3172 :
3173 : static inline bool dir_relax_shared(struct inode *inode)
3174 : {
3175 : inode_unlock_shared(inode);
3176 : inode_lock_shared(inode);
3177 : return !IS_DEADDIR(inode);
3178 : }
3179 :
3180 : extern bool path_noexec(const struct path *path);
3181 : extern void inode_nohighmem(struct inode *inode);
3182 :
3183 : /* mm/fadvise.c */
3184 : extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len,
3185 : int advice);
3186 : extern int generic_fadvise(struct file *file, loff_t offset, loff_t len,
3187 : int advice);
3188 :
3189 : #endif /* _LINUX_FS_H */
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