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 :
78 : extern void __init inode_init(void);
79 : extern void __init inode_init_early(void);
80 : extern void __init files_init(void);
81 : extern void __init files_maxfiles_init(void);
82 :
83 : extern unsigned long get_max_files(void);
84 : extern unsigned int sysctl_nr_open;
85 :
86 : typedef __kernel_rwf_t rwf_t;
87 :
88 : struct buffer_head;
89 : typedef int (get_block_t)(struct inode *inode, sector_t iblock,
90 : struct buffer_head *bh_result, int create);
91 : typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
92 : ssize_t bytes, void *private);
93 :
94 : #define MAY_EXEC 0x00000001
95 : #define MAY_WRITE 0x00000002
96 : #define MAY_READ 0x00000004
97 : #define MAY_APPEND 0x00000008
98 : #define MAY_ACCESS 0x00000010
99 : #define MAY_OPEN 0x00000020
100 : #define MAY_CHDIR 0x00000040
101 : /* called from RCU mode, don't block */
102 : #define MAY_NOT_BLOCK 0x00000080
103 :
104 : /*
105 : * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
106 : * to O_WRONLY and O_RDWR via the strange trick in do_dentry_open()
107 : */
108 :
109 : /* file is open for reading */
110 : #define FMODE_READ ((__force fmode_t)0x1)
111 : /* file is open for writing */
112 : #define FMODE_WRITE ((__force fmode_t)0x2)
113 : /* file is seekable */
114 : #define FMODE_LSEEK ((__force fmode_t)0x4)
115 : /* file can be accessed using pread */
116 : #define FMODE_PREAD ((__force fmode_t)0x8)
117 : /* file can be accessed using pwrite */
118 : #define FMODE_PWRITE ((__force fmode_t)0x10)
119 : /* File is opened for execution with sys_execve / sys_uselib */
120 : #define FMODE_EXEC ((__force fmode_t)0x20)
121 : /* File is opened with O_NDELAY (only set for block devices) */
122 : #define FMODE_NDELAY ((__force fmode_t)0x40)
123 : /* File is opened with O_EXCL (only set for block devices) */
124 : #define FMODE_EXCL ((__force fmode_t)0x80)
125 : /* File is opened using open(.., 3, ..) and is writeable only for ioctls
126 : (specialy hack for floppy.c) */
127 : #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
128 : /* 32bit hashes as llseek() offset (for directories) */
129 : #define FMODE_32BITHASH ((__force fmode_t)0x200)
130 : /* 64bit hashes as llseek() offset (for directories) */
131 : #define FMODE_64BITHASH ((__force fmode_t)0x400)
132 :
133 : /*
134 : * Don't update ctime and mtime.
135 : *
136 : * Currently a special hack for the XFS open_by_handle ioctl, but we'll
137 : * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
138 : */
139 : #define FMODE_NOCMTIME ((__force fmode_t)0x800)
140 :
141 : /* Expect random access pattern */
142 : #define FMODE_RANDOM ((__force fmode_t)0x1000)
143 :
144 : /* File is huge (eg. /dev/mem): treat loff_t as unsigned */
145 : #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
146 :
147 : /* File is opened with O_PATH; almost nothing can be done with it */
148 : #define FMODE_PATH ((__force fmode_t)0x4000)
149 :
150 : /* File needs atomic accesses to f_pos */
151 : #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
152 : /* Write access to underlying fs */
153 : #define FMODE_WRITER ((__force fmode_t)0x10000)
154 : /* Has read method(s) */
155 : #define FMODE_CAN_READ ((__force fmode_t)0x20000)
156 : /* Has write method(s) */
157 : #define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
158 :
159 : #define FMODE_OPENED ((__force fmode_t)0x80000)
160 : #define FMODE_CREATED ((__force fmode_t)0x100000)
161 :
162 : /* File is stream-like */
163 : #define FMODE_STREAM ((__force fmode_t)0x200000)
164 :
165 : /* File was opened by fanotify and shouldn't generate fanotify events */
166 : #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
167 :
168 : /* File is capable of returning -EAGAIN if I/O will block */
169 : #define FMODE_NOWAIT ((__force fmode_t)0x8000000)
170 :
171 : /* File represents mount that needs unmounting */
172 : #define FMODE_NEED_UNMOUNT ((__force fmode_t)0x10000000)
173 :
174 : /* File does not contribute to nr_files count */
175 : #define FMODE_NOACCOUNT ((__force fmode_t)0x20000000)
176 :
177 : /* File supports async buffered reads */
178 : #define FMODE_BUF_RASYNC ((__force fmode_t)0x40000000)
179 :
180 : /*
181 : * Attribute flags. These should be or-ed together to figure out what
182 : * has been changed!
183 : */
184 : #define ATTR_MODE (1 << 0)
185 : #define ATTR_UID (1 << 1)
186 : #define ATTR_GID (1 << 2)
187 : #define ATTR_SIZE (1 << 3)
188 : #define ATTR_ATIME (1 << 4)
189 : #define ATTR_MTIME (1 << 5)
190 : #define ATTR_CTIME (1 << 6)
191 : #define ATTR_ATIME_SET (1 << 7)
192 : #define ATTR_MTIME_SET (1 << 8)
193 : #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
194 : #define ATTR_KILL_SUID (1 << 11)
195 : #define ATTR_KILL_SGID (1 << 12)
196 : #define ATTR_FILE (1 << 13)
197 : #define ATTR_KILL_PRIV (1 << 14)
198 : #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
199 : #define ATTR_TIMES_SET (1 << 16)
200 : #define ATTR_TOUCH (1 << 17)
201 :
202 : /*
203 : * Whiteout is represented by a char device. The following constants define the
204 : * mode and device number to use.
205 : */
206 : #define WHITEOUT_MODE 0
207 : #define WHITEOUT_DEV 0
208 :
209 : /*
210 : * This is the Inode Attributes structure, used for notify_change(). It
211 : * uses the above definitions as flags, to know which values have changed.
212 : * Also, in this manner, a Filesystem can look at only the values it cares
213 : * about. Basically, these are the attributes that the VFS layer can
214 : * request to change from the FS layer.
215 : *
216 : * Derek Atkins <warlord@MIT.EDU> 94-10-20
217 : */
218 : struct iattr {
219 : unsigned int ia_valid;
220 : umode_t ia_mode;
221 : kuid_t ia_uid;
222 : kgid_t ia_gid;
223 : loff_t ia_size;
224 : struct timespec64 ia_atime;
225 : struct timespec64 ia_mtime;
226 : struct timespec64 ia_ctime;
227 :
228 : /*
229 : * Not an attribute, but an auxiliary info for filesystems wanting to
230 : * implement an ftruncate() like method. NOTE: filesystem should
231 : * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
232 : */
233 : struct file *ia_file;
234 : };
235 :
236 : /*
237 : * Includes for diskquotas.
238 : */
239 : #include <linux/quota.h>
240 :
241 : /*
242 : * Maximum number of layers of fs stack. Needs to be limited to
243 : * prevent kernel stack overflow
244 : */
245 : #define FILESYSTEM_MAX_STACK_DEPTH 2
246 :
247 : /**
248 : * enum positive_aop_returns - aop return codes with specific semantics
249 : *
250 : * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
251 : * completed, that the page is still locked, and
252 : * should be considered active. The VM uses this hint
253 : * to return the page to the active list -- it won't
254 : * be a candidate for writeback again in the near
255 : * future. Other callers must be careful to unlock
256 : * the page if they get this return. Returned by
257 : * writepage();
258 : *
259 : * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
260 : * unlocked it and the page might have been truncated.
261 : * The caller should back up to acquiring a new page and
262 : * trying again. The aop will be taking reasonable
263 : * precautions not to livelock. If the caller held a page
264 : * reference, it should drop it before retrying. Returned
265 : * by readpage().
266 : *
267 : * address_space_operation functions return these large constants to indicate
268 : * special semantics to the caller. These are much larger than the bytes in a
269 : * page to allow for functions that return the number of bytes operated on in a
270 : * given page.
271 : */
272 :
273 : enum positive_aop_returns {
274 : AOP_WRITEPAGE_ACTIVATE = 0x80000,
275 : AOP_TRUNCATED_PAGE = 0x80001,
276 : };
277 :
278 : #define AOP_FLAG_NOFS 0x0002 /* used by filesystem to direct
279 : * helper code (eg buffer layer)
280 : * to clear GFP_FS from alloc */
281 :
282 : /*
283 : * oh the beauties of C type declarations.
284 : */
285 : struct page;
286 : struct address_space;
287 : struct writeback_control;
288 : struct readahead_control;
289 :
290 : /*
291 : * Write life time hint values.
292 : * Stored in struct inode as u8.
293 : */
294 : enum rw_hint {
295 : WRITE_LIFE_NOT_SET = 0,
296 : WRITE_LIFE_NONE = RWH_WRITE_LIFE_NONE,
297 : WRITE_LIFE_SHORT = RWH_WRITE_LIFE_SHORT,
298 : WRITE_LIFE_MEDIUM = RWH_WRITE_LIFE_MEDIUM,
299 : WRITE_LIFE_LONG = RWH_WRITE_LIFE_LONG,
300 : WRITE_LIFE_EXTREME = RWH_WRITE_LIFE_EXTREME,
301 : };
302 :
303 : /* Match RWF_* bits to IOCB bits */
304 : #define IOCB_HIPRI (__force int) RWF_HIPRI
305 : #define IOCB_DSYNC (__force int) RWF_DSYNC
306 : #define IOCB_SYNC (__force int) RWF_SYNC
307 : #define IOCB_NOWAIT (__force int) RWF_NOWAIT
308 : #define IOCB_APPEND (__force int) RWF_APPEND
309 :
310 : /* non-RWF related bits - start at 16 */
311 : #define IOCB_EVENTFD (1 << 16)
312 : #define IOCB_DIRECT (1 << 17)
313 : #define IOCB_WRITE (1 << 18)
314 : /* iocb->ki_waitq is valid */
315 : #define IOCB_WAITQ (1 << 19)
316 : #define IOCB_NOIO (1 << 20)
317 : /* can use bio alloc cache */
318 : #define IOCB_ALLOC_CACHE (1 << 21)
319 :
320 : struct kiocb {
321 : struct file *ki_filp;
322 :
323 : /* The 'ki_filp' pointer is shared in a union for aio */
324 : randomized_struct_fields_start
325 :
326 : loff_t ki_pos;
327 : void (*ki_complete)(struct kiocb *iocb, long ret);
328 : void *private;
329 : int ki_flags;
330 : u16 ki_ioprio; /* See linux/ioprio.h */
331 : struct wait_page_queue *ki_waitq; /* for async buffered IO */
332 : randomized_struct_fields_end
333 : };
334 :
335 : static inline bool is_sync_kiocb(struct kiocb *kiocb)
336 : {
337 : return kiocb->ki_complete == NULL;
338 : }
339 :
340 : struct address_space_operations {
341 : int (*writepage)(struct page *page, struct writeback_control *wbc);
342 : int (*readpage)(struct file *, struct page *);
343 :
344 : /* Write back some dirty pages from this mapping. */
345 : int (*writepages)(struct address_space *, struct writeback_control *);
346 :
347 : /* Mark a folio dirty. Return true if this dirtied it */
348 : bool (*dirty_folio)(struct address_space *, struct folio *);
349 :
350 : void (*readahead)(struct readahead_control *);
351 :
352 : int (*write_begin)(struct file *, struct address_space *mapping,
353 : loff_t pos, unsigned len, unsigned flags,
354 : struct page **pagep, void **fsdata);
355 : int (*write_end)(struct file *, struct address_space *mapping,
356 : loff_t pos, unsigned len, unsigned copied,
357 : struct page *page, void *fsdata);
358 :
359 : /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
360 : sector_t (*bmap)(struct address_space *, sector_t);
361 : void (*invalidate_folio) (struct folio *, size_t offset, size_t len);
362 : int (*releasepage) (struct page *, gfp_t);
363 : void (*freepage)(struct page *);
364 : ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
365 : /*
366 : * migrate the contents of a page to the specified target. If
367 : * migrate_mode is MIGRATE_ASYNC, it must not block.
368 : */
369 : int (*migratepage) (struct address_space *,
370 : struct page *, struct page *, enum migrate_mode);
371 : bool (*isolate_page)(struct page *, isolate_mode_t);
372 : void (*putback_page)(struct page *);
373 : int (*launder_folio)(struct folio *);
374 : bool (*is_partially_uptodate) (struct folio *, size_t from,
375 : size_t count);
376 : void (*is_dirty_writeback) (struct page *, bool *, bool *);
377 : int (*error_remove_page)(struct address_space *, struct page *);
378 :
379 : /* swapfile support */
380 : int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
381 : sector_t *span);
382 : void (*swap_deactivate)(struct file *file);
383 : };
384 :
385 : extern const struct address_space_operations empty_aops;
386 :
387 : /*
388 : * pagecache_write_begin/pagecache_write_end must be used by general code
389 : * to write into the pagecache.
390 : */
391 : int pagecache_write_begin(struct file *, struct address_space *mapping,
392 : loff_t pos, unsigned len, unsigned flags,
393 : struct page **pagep, void **fsdata);
394 :
395 : int pagecache_write_end(struct file *, struct address_space *mapping,
396 : loff_t pos, unsigned len, unsigned copied,
397 : struct page *page, void *fsdata);
398 :
399 : /**
400 : * struct address_space - Contents of a cacheable, mappable object.
401 : * @host: Owner, either the inode or the block_device.
402 : * @i_pages: Cached pages.
403 : * @invalidate_lock: Guards coherency between page cache contents and
404 : * file offset->disk block mappings in the filesystem during invalidates.
405 : * It is also used to block modification of page cache contents through
406 : * memory mappings.
407 : * @gfp_mask: Memory allocation flags to use for allocating pages.
408 : * @i_mmap_writable: Number of VM_SHARED mappings.
409 : * @nr_thps: Number of THPs in the pagecache (non-shmem only).
410 : * @i_mmap: Tree of private and shared mappings.
411 : * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
412 : * @nrpages: Number of page entries, protected by the i_pages lock.
413 : * @writeback_index: Writeback starts here.
414 : * @a_ops: Methods.
415 : * @flags: Error bits and flags (AS_*).
416 : * @wb_err: The most recent error which has occurred.
417 : * @private_lock: For use by the owner of the address_space.
418 : * @private_list: For use by the owner of the address_space.
419 : * @private_data: For use by the owner of the address_space.
420 : */
421 : struct address_space {
422 : struct inode *host;
423 : struct xarray i_pages;
424 : struct rw_semaphore invalidate_lock;
425 : gfp_t gfp_mask;
426 : atomic_t i_mmap_writable;
427 : #ifdef CONFIG_READ_ONLY_THP_FOR_FS
428 : /* number of thp, only for non-shmem files */
429 : atomic_t nr_thps;
430 : #endif
431 : struct rb_root_cached i_mmap;
432 : struct rw_semaphore i_mmap_rwsem;
433 : unsigned long nrpages;
434 : pgoff_t writeback_index;
435 : const struct address_space_operations *a_ops;
436 : unsigned long flags;
437 : errseq_t wb_err;
438 : spinlock_t private_lock;
439 : struct list_head private_list;
440 : void *private_data;
441 : } __attribute__((aligned(sizeof(long)))) __randomize_layout;
442 : /*
443 : * On most architectures that alignment is already the case; but
444 : * must be enforced here for CRIS, to let the least significant bit
445 : * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
446 : */
447 :
448 : /* XArray tags, for tagging dirty and writeback pages in the pagecache. */
449 : #define PAGECACHE_TAG_DIRTY XA_MARK_0
450 : #define PAGECACHE_TAG_WRITEBACK XA_MARK_1
451 : #define PAGECACHE_TAG_TOWRITE XA_MARK_2
452 :
453 : /*
454 : * Returns true if any of the pages in the mapping are marked with the tag.
455 : */
456 : static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
457 : {
458 0 : return xa_marked(&mapping->i_pages, tag);
459 : }
460 :
461 : static inline void i_mmap_lock_write(struct address_space *mapping)
462 : {
463 0 : down_write(&mapping->i_mmap_rwsem);
464 : }
465 :
466 : static inline int i_mmap_trylock_write(struct address_space *mapping)
467 : {
468 : return down_write_trylock(&mapping->i_mmap_rwsem);
469 : }
470 :
471 : static inline void i_mmap_unlock_write(struct address_space *mapping)
472 : {
473 0 : up_write(&mapping->i_mmap_rwsem);
474 : }
475 :
476 : static inline void i_mmap_lock_read(struct address_space *mapping)
477 : {
478 0 : down_read(&mapping->i_mmap_rwsem);
479 : }
480 :
481 : static inline void i_mmap_unlock_read(struct address_space *mapping)
482 : {
483 0 : up_read(&mapping->i_mmap_rwsem);
484 : }
485 :
486 : static inline void i_mmap_assert_locked(struct address_space *mapping)
487 : {
488 : lockdep_assert_held(&mapping->i_mmap_rwsem);
489 : }
490 :
491 : static inline void i_mmap_assert_write_locked(struct address_space *mapping)
492 : {
493 : lockdep_assert_held_write(&mapping->i_mmap_rwsem);
494 : }
495 :
496 : /*
497 : * Might pages of this file be mapped into userspace?
498 : */
499 : static inline int mapping_mapped(struct address_space *mapping)
500 : {
501 : return !RB_EMPTY_ROOT(&mapping->i_mmap.rb_root);
502 : }
503 :
504 : /*
505 : * Might pages of this file have been modified in userspace?
506 : * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap
507 : * marks vma as VM_SHARED if it is shared, and the file was opened for
508 : * writing i.e. vma may be mprotected writable even if now readonly.
509 : *
510 : * If i_mmap_writable is negative, no new writable mappings are allowed. You
511 : * can only deny writable mappings, if none exists right now.
512 : */
513 : static inline int mapping_writably_mapped(struct address_space *mapping)
514 : {
515 0 : return atomic_read(&mapping->i_mmap_writable) > 0;
516 : }
517 :
518 : static inline int mapping_map_writable(struct address_space *mapping)
519 : {
520 0 : return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
521 0 : 0 : -EPERM;
522 : }
523 :
524 : static inline void mapping_unmap_writable(struct address_space *mapping)
525 : {
526 0 : atomic_dec(&mapping->i_mmap_writable);
527 : }
528 :
529 : static inline int mapping_deny_writable(struct address_space *mapping)
530 : {
531 : return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
532 : 0 : -EBUSY;
533 : }
534 :
535 : static inline void mapping_allow_writable(struct address_space *mapping)
536 : {
537 0 : atomic_inc(&mapping->i_mmap_writable);
538 : }
539 :
540 : /*
541 : * Use sequence counter to get consistent i_size on 32-bit processors.
542 : */
543 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
544 : #include <linux/seqlock.h>
545 : #define __NEED_I_SIZE_ORDERED
546 : #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
547 : #else
548 : #define i_size_ordered_init(inode) do { } while (0)
549 : #endif
550 :
551 : struct posix_acl;
552 : #define ACL_NOT_CACHED ((void *)(-1))
553 : /*
554 : * ACL_DONT_CACHE is for stacked filesystems, that rely on underlying fs to
555 : * cache the ACL. This also means that ->get_acl() can be called in RCU mode
556 : * with the LOOKUP_RCU flag.
557 : */
558 : #define ACL_DONT_CACHE ((void *)(-3))
559 :
560 : static inline struct posix_acl *
561 : uncached_acl_sentinel(struct task_struct *task)
562 : {
563 : return (void *)task + 1;
564 : }
565 :
566 : static inline bool
567 : is_uncached_acl(struct posix_acl *acl)
568 : {
569 : return (long)acl & 1;
570 : }
571 :
572 : #define IOP_FASTPERM 0x0001
573 : #define IOP_LOOKUP 0x0002
574 : #define IOP_NOFOLLOW 0x0004
575 : #define IOP_XATTR 0x0008
576 : #define IOP_DEFAULT_READLINK 0x0010
577 :
578 : struct fsnotify_mark_connector;
579 :
580 : /*
581 : * Keep mostly read-only and often accessed (especially for
582 : * the RCU path lookup and 'stat' data) fields at the beginning
583 : * of the 'struct inode'
584 : */
585 : struct inode {
586 : umode_t i_mode;
587 : unsigned short i_opflags;
588 : kuid_t i_uid;
589 : kgid_t i_gid;
590 : unsigned int i_flags;
591 :
592 : #ifdef CONFIG_FS_POSIX_ACL
593 : struct posix_acl *i_acl;
594 : struct posix_acl *i_default_acl;
595 : #endif
596 :
597 : const struct inode_operations *i_op;
598 : struct super_block *i_sb;
599 : struct address_space *i_mapping;
600 :
601 : #ifdef CONFIG_SECURITY
602 : void *i_security;
603 : #endif
604 :
605 : /* Stat data, not accessed from path walking */
606 : unsigned long i_ino;
607 : /*
608 : * Filesystems may only read i_nlink directly. They shall use the
609 : * following functions for modification:
610 : *
611 : * (set|clear|inc|drop)_nlink
612 : * inode_(inc|dec)_link_count
613 : */
614 : union {
615 : const unsigned int i_nlink;
616 : unsigned int __i_nlink;
617 : };
618 : dev_t i_rdev;
619 : loff_t i_size;
620 : struct timespec64 i_atime;
621 : struct timespec64 i_mtime;
622 : struct timespec64 i_ctime;
623 : spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
624 : unsigned short i_bytes;
625 : u8 i_blkbits;
626 : u8 i_write_hint;
627 : blkcnt_t i_blocks;
628 :
629 : #ifdef __NEED_I_SIZE_ORDERED
630 : seqcount_t i_size_seqcount;
631 : #endif
632 :
633 : /* Misc */
634 : unsigned long i_state;
635 : struct rw_semaphore i_rwsem;
636 :
637 : unsigned long dirtied_when; /* jiffies of first dirtying */
638 : unsigned long dirtied_time_when;
639 :
640 : struct hlist_node i_hash;
641 : struct list_head i_io_list; /* backing dev IO list */
642 : #ifdef CONFIG_CGROUP_WRITEBACK
643 : struct bdi_writeback *i_wb; /* the associated cgroup wb */
644 :
645 : /* foreign inode detection, see wbc_detach_inode() */
646 : int i_wb_frn_winner;
647 : u16 i_wb_frn_avg_time;
648 : u16 i_wb_frn_history;
649 : #endif
650 : struct list_head i_lru; /* inode LRU list */
651 : struct list_head i_sb_list;
652 : struct list_head i_wb_list; /* backing dev writeback list */
653 : union {
654 : struct hlist_head i_dentry;
655 : struct rcu_head i_rcu;
656 : };
657 : atomic64_t i_version;
658 : atomic64_t i_sequence; /* see futex */
659 : atomic_t i_count;
660 : atomic_t i_dio_count;
661 : atomic_t i_writecount;
662 : #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
663 : atomic_t i_readcount; /* struct files open RO */
664 : #endif
665 : union {
666 : const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
667 : void (*free_inode)(struct inode *);
668 : };
669 : struct file_lock_context *i_flctx;
670 : struct address_space i_data;
671 : struct list_head i_devices;
672 : union {
673 : struct pipe_inode_info *i_pipe;
674 : struct cdev *i_cdev;
675 : char *i_link;
676 : unsigned i_dir_seq;
677 : };
678 :
679 : __u32 i_generation;
680 :
681 : #ifdef CONFIG_FSNOTIFY
682 : __u32 i_fsnotify_mask; /* all events this inode cares about */
683 : struct fsnotify_mark_connector __rcu *i_fsnotify_marks;
684 : #endif
685 :
686 : #ifdef CONFIG_FS_ENCRYPTION
687 : struct fscrypt_info *i_crypt_info;
688 : #endif
689 :
690 : #ifdef CONFIG_FS_VERITY
691 : struct fsverity_info *i_verity_info;
692 : #endif
693 :
694 : void *i_private; /* fs or device private pointer */
695 : } __randomize_layout;
696 :
697 : struct timespec64 timestamp_truncate(struct timespec64 t, struct inode *inode);
698 :
699 : static inline unsigned int i_blocksize(const struct inode *node)
700 : {
701 0 : return (1 << node->i_blkbits);
702 : }
703 :
704 : static inline int inode_unhashed(struct inode *inode)
705 : {
706 0 : return hlist_unhashed(&inode->i_hash);
707 : }
708 :
709 : /*
710 : * __mark_inode_dirty expects inodes to be hashed. Since we don't
711 : * want special inodes in the fileset inode space, we make them
712 : * appear hashed, but do not put on any lists. hlist_del()
713 : * will work fine and require no locking.
714 : */
715 : static inline void inode_fake_hash(struct inode *inode)
716 : {
717 : hlist_add_fake(&inode->i_hash);
718 : }
719 :
720 : /*
721 : * inode->i_mutex nesting subclasses for the lock validator:
722 : *
723 : * 0: the object of the current VFS operation
724 : * 1: parent
725 : * 2: child/target
726 : * 3: xattr
727 : * 4: second non-directory
728 : * 5: second parent (when locking independent directories in rename)
729 : *
730 : * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
731 : * non-directories at once.
732 : *
733 : * The locking order between these classes is
734 : * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
735 : */
736 : enum inode_i_mutex_lock_class
737 : {
738 : I_MUTEX_NORMAL,
739 : I_MUTEX_PARENT,
740 : I_MUTEX_CHILD,
741 : I_MUTEX_XATTR,
742 : I_MUTEX_NONDIR2,
743 : I_MUTEX_PARENT2,
744 : };
745 :
746 : static inline void inode_lock(struct inode *inode)
747 : {
748 2 : down_write(&inode->i_rwsem);
749 : }
750 :
751 : static inline void inode_unlock(struct inode *inode)
752 : {
753 5 : up_write(&inode->i_rwsem);
754 : }
755 :
756 : static inline void inode_lock_shared(struct inode *inode)
757 : {
758 0 : down_read(&inode->i_rwsem);
759 : }
760 :
761 : static inline void inode_unlock_shared(struct inode *inode)
762 : {
763 0 : up_read(&inode->i_rwsem);
764 : }
765 :
766 : static inline int inode_trylock(struct inode *inode)
767 : {
768 0 : return down_write_trylock(&inode->i_rwsem);
769 : }
770 :
771 : static inline int inode_trylock_shared(struct inode *inode)
772 : {
773 0 : return down_read_trylock(&inode->i_rwsem);
774 : }
775 :
776 : static inline int inode_is_locked(struct inode *inode)
777 : {
778 0 : return rwsem_is_locked(&inode->i_rwsem);
779 : }
780 :
781 : static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
782 : {
783 3 : down_write_nested(&inode->i_rwsem, subclass);
784 : }
785 :
786 : static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass)
787 : {
788 : down_read_nested(&inode->i_rwsem, subclass);
789 : }
790 :
791 : static inline void filemap_invalidate_lock(struct address_space *mapping)
792 : {
793 0 : down_write(&mapping->invalidate_lock);
794 : }
795 :
796 : static inline void filemap_invalidate_unlock(struct address_space *mapping)
797 : {
798 0 : up_write(&mapping->invalidate_lock);
799 : }
800 :
801 : static inline void filemap_invalidate_lock_shared(struct address_space *mapping)
802 : {
803 0 : down_read(&mapping->invalidate_lock);
804 : }
805 :
806 : static inline int filemap_invalidate_trylock_shared(
807 : struct address_space *mapping)
808 : {
809 0 : return down_read_trylock(&mapping->invalidate_lock);
810 : }
811 :
812 : static inline void filemap_invalidate_unlock_shared(
813 : struct address_space *mapping)
814 : {
815 0 : up_read(&mapping->invalidate_lock);
816 : }
817 :
818 : void lock_two_nondirectories(struct inode *, struct inode*);
819 : void unlock_two_nondirectories(struct inode *, struct inode*);
820 :
821 : void filemap_invalidate_lock_two(struct address_space *mapping1,
822 : struct address_space *mapping2);
823 : void filemap_invalidate_unlock_two(struct address_space *mapping1,
824 : struct address_space *mapping2);
825 :
826 :
827 : /*
828 : * NOTE: in a 32bit arch with a preemptable kernel and
829 : * an UP compile the i_size_read/write must be atomic
830 : * with respect to the local cpu (unlike with preempt disabled),
831 : * but they don't need to be atomic with respect to other cpus like in
832 : * true SMP (so they need either to either locally disable irq around
833 : * the read or for example on x86 they can be still implemented as a
834 : * cmpxchg8b without the need of the lock prefix). For SMP compiles
835 : * and 64bit archs it makes no difference if preempt is enabled or not.
836 : */
837 : static inline loff_t i_size_read(const struct inode *inode)
838 : {
839 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
840 : loff_t i_size;
841 : unsigned int seq;
842 :
843 : do {
844 : seq = read_seqcount_begin(&inode->i_size_seqcount);
845 : i_size = inode->i_size;
846 : } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
847 : return i_size;
848 : #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
849 : loff_t i_size;
850 :
851 : preempt_disable();
852 : i_size = inode->i_size;
853 : preempt_enable();
854 : return i_size;
855 : #else
856 : return inode->i_size;
857 : #endif
858 : }
859 :
860 : /*
861 : * NOTE: unlike i_size_read(), i_size_write() does need locking around it
862 : * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
863 : * can be lost, resulting in subsequent i_size_read() calls spinning forever.
864 : */
865 : static inline void i_size_write(struct inode *inode, loff_t i_size)
866 : {
867 : #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
868 : preempt_disable();
869 : write_seqcount_begin(&inode->i_size_seqcount);
870 : inode->i_size = i_size;
871 : write_seqcount_end(&inode->i_size_seqcount);
872 : preempt_enable();
873 : #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
874 : preempt_disable();
875 : inode->i_size = i_size;
876 : preempt_enable();
877 : #else
878 0 : inode->i_size = i_size;
879 : #endif
880 : }
881 :
882 : static inline unsigned iminor(const struct inode *inode)
883 : {
884 0 : return MINOR(inode->i_rdev);
885 : }
886 :
887 : static inline unsigned imajor(const struct inode *inode)
888 : {
889 0 : return MAJOR(inode->i_rdev);
890 : }
891 :
892 : struct fown_struct {
893 : rwlock_t lock; /* protects pid, uid, euid fields */
894 : struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
895 : enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
896 : kuid_t uid, euid; /* uid/euid of process setting the owner */
897 : int signum; /* posix.1b rt signal to be delivered on IO */
898 : };
899 :
900 : /**
901 : * struct file_ra_state - Track a file's readahead state.
902 : * @start: Where the most recent readahead started.
903 : * @size: Number of pages read in the most recent readahead.
904 : * @async_size: Numer of pages that were/are not needed immediately
905 : * and so were/are genuinely "ahead". Start next readahead when
906 : * the first of these pages is accessed.
907 : * @ra_pages: Maximum size of a readahead request, copied from the bdi.
908 : * @mmap_miss: How many mmap accesses missed in the page cache.
909 : * @prev_pos: The last byte in the most recent read request.
910 : *
911 : * When this structure is passed to ->readahead(), the "most recent"
912 : * readahead means the current readahead.
913 : */
914 : struct file_ra_state {
915 : pgoff_t start;
916 : unsigned int size;
917 : unsigned int async_size;
918 : unsigned int ra_pages;
919 : unsigned int mmap_miss;
920 : loff_t prev_pos;
921 : };
922 :
923 : /*
924 : * Check if @index falls in the readahead windows.
925 : */
926 : static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
927 : {
928 : return (index >= ra->start &&
929 : index < ra->start + ra->size);
930 : }
931 :
932 : struct file {
933 : union {
934 : struct llist_node fu_llist;
935 : struct rcu_head fu_rcuhead;
936 : } f_u;
937 : struct path f_path;
938 : struct inode *f_inode; /* cached value */
939 : const struct file_operations *f_op;
940 :
941 : /*
942 : * Protects f_ep, f_flags.
943 : * Must not be taken from IRQ context.
944 : */
945 : spinlock_t f_lock;
946 : atomic_long_t f_count;
947 : unsigned int f_flags;
948 : fmode_t f_mode;
949 : struct mutex f_pos_lock;
950 : loff_t f_pos;
951 : struct fown_struct f_owner;
952 : const struct cred *f_cred;
953 : struct file_ra_state f_ra;
954 :
955 : u64 f_version;
956 : #ifdef CONFIG_SECURITY
957 : void *f_security;
958 : #endif
959 : /* needed for tty driver, and maybe others */
960 : void *private_data;
961 :
962 : #ifdef CONFIG_EPOLL
963 : /* Used by fs/eventpoll.c to link all the hooks to this file */
964 : struct hlist_head *f_ep;
965 : #endif /* #ifdef CONFIG_EPOLL */
966 : struct address_space *f_mapping;
967 : errseq_t f_wb_err;
968 : errseq_t f_sb_err; /* for syncfs */
969 : } __randomize_layout
970 : __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
971 :
972 : struct file_handle {
973 : __u32 handle_bytes;
974 : int handle_type;
975 : /* file identifier */
976 : unsigned char f_handle[];
977 : };
978 :
979 : static inline struct file *get_file(struct file *f)
980 : {
981 0 : atomic_long_inc(&f->f_count);
982 : return f;
983 : }
984 : #define get_file_rcu_many(x, cnt) \
985 : atomic_long_add_unless(&(x)->f_count, (cnt), 0)
986 : #define get_file_rcu(x) get_file_rcu_many((x), 1)
987 : #define file_count(x) atomic_long_read(&(x)->f_count)
988 :
989 : #define MAX_NON_LFS ((1UL<<31) - 1)
990 :
991 : /* Page cache limit. The filesystems should put that into their s_maxbytes
992 : limits, otherwise bad things can happen in VM. */
993 : #if BITS_PER_LONG==32
994 : #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
995 : #elif BITS_PER_LONG==64
996 : #define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
997 : #endif
998 :
999 : #define FL_POSIX 1
1000 : #define FL_FLOCK 2
1001 : #define FL_DELEG 4 /* NFSv4 delegation */
1002 : #define FL_ACCESS 8 /* not trying to lock, just looking */
1003 : #define FL_EXISTS 16 /* when unlocking, test for existence */
1004 : #define FL_LEASE 32 /* lease held on this file */
1005 : #define FL_CLOSE 64 /* unlock on close */
1006 : #define FL_SLEEP 128 /* A blocking lock */
1007 : #define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
1008 : #define FL_UNLOCK_PENDING 512 /* Lease is being broken */
1009 : #define FL_OFDLCK 1024 /* lock is "owned" by struct file */
1010 : #define FL_LAYOUT 2048 /* outstanding pNFS layout */
1011 : #define FL_RECLAIM 4096 /* reclaiming from a reboot server */
1012 :
1013 : #define FL_CLOSE_POSIX (FL_POSIX | FL_CLOSE)
1014 :
1015 : /*
1016 : * Special return value from posix_lock_file() and vfs_lock_file() for
1017 : * asynchronous locking.
1018 : */
1019 : #define FILE_LOCK_DEFERRED 1
1020 :
1021 : /* legacy typedef, should eventually be removed */
1022 : typedef void *fl_owner_t;
1023 :
1024 : struct file_lock;
1025 :
1026 : struct file_lock_operations {
1027 : void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
1028 : void (*fl_release_private)(struct file_lock *);
1029 : };
1030 :
1031 : struct lock_manager_operations {
1032 : fl_owner_t (*lm_get_owner)(fl_owner_t);
1033 : void (*lm_put_owner)(fl_owner_t);
1034 : void (*lm_notify)(struct file_lock *); /* unblock callback */
1035 : int (*lm_grant)(struct file_lock *, int);
1036 : bool (*lm_break)(struct file_lock *);
1037 : int (*lm_change)(struct file_lock *, int, struct list_head *);
1038 : void (*lm_setup)(struct file_lock *, void **);
1039 : bool (*lm_breaker_owns_lease)(struct file_lock *);
1040 : };
1041 :
1042 : struct lock_manager {
1043 : struct list_head list;
1044 : /*
1045 : * NFSv4 and up also want opens blocked during the grace period;
1046 : * NLM doesn't care:
1047 : */
1048 : bool block_opens;
1049 : };
1050 :
1051 : struct net;
1052 : void locks_start_grace(struct net *, struct lock_manager *);
1053 : void locks_end_grace(struct lock_manager *);
1054 : bool locks_in_grace(struct net *);
1055 : bool opens_in_grace(struct net *);
1056 :
1057 : /* that will die - we need it for nfs_lock_info */
1058 : #include <linux/nfs_fs_i.h>
1059 :
1060 : /*
1061 : * struct file_lock represents a generic "file lock". It's used to represent
1062 : * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
1063 : * note that the same struct is used to represent both a request for a lock and
1064 : * the lock itself, but the same object is never used for both.
1065 : *
1066 : * FIXME: should we create a separate "struct lock_request" to help distinguish
1067 : * these two uses?
1068 : *
1069 : * The varous i_flctx lists are ordered by:
1070 : *
1071 : * 1) lock owner
1072 : * 2) lock range start
1073 : * 3) lock range end
1074 : *
1075 : * Obviously, the last two criteria only matter for POSIX locks.
1076 : */
1077 : struct file_lock {
1078 : struct file_lock *fl_blocker; /* The lock, that is blocking us */
1079 : struct list_head fl_list; /* link into file_lock_context */
1080 : struct hlist_node fl_link; /* node in global lists */
1081 : struct list_head fl_blocked_requests; /* list of requests with
1082 : * ->fl_blocker pointing here
1083 : */
1084 : struct list_head fl_blocked_member; /* node in
1085 : * ->fl_blocker->fl_blocked_requests
1086 : */
1087 : fl_owner_t fl_owner;
1088 : unsigned int fl_flags;
1089 : unsigned char fl_type;
1090 : unsigned int fl_pid;
1091 : int fl_link_cpu; /* what cpu's list is this on? */
1092 : wait_queue_head_t fl_wait;
1093 : struct file *fl_file;
1094 : loff_t fl_start;
1095 : loff_t fl_end;
1096 :
1097 : struct fasync_struct * fl_fasync; /* for lease break notifications */
1098 : /* for lease breaks: */
1099 : unsigned long fl_break_time;
1100 : unsigned long fl_downgrade_time;
1101 :
1102 : const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
1103 : const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
1104 : union {
1105 : struct nfs_lock_info nfs_fl;
1106 : struct nfs4_lock_info nfs4_fl;
1107 : struct {
1108 : struct list_head link; /* link in AFS vnode's pending_locks list */
1109 : int state; /* state of grant or error if -ve */
1110 : unsigned int debug_id;
1111 : } afs;
1112 : } fl_u;
1113 : } __randomize_layout;
1114 :
1115 : struct file_lock_context {
1116 : spinlock_t flc_lock;
1117 : struct list_head flc_flock;
1118 : struct list_head flc_posix;
1119 : struct list_head flc_lease;
1120 : };
1121 :
1122 : /* The following constant reflects the upper bound of the file/locking space */
1123 : #ifndef OFFSET_MAX
1124 : #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
1125 : #define OFFSET_MAX INT_LIMIT(loff_t)
1126 : #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
1127 : #endif
1128 :
1129 : extern void send_sigio(struct fown_struct *fown, int fd, int band);
1130 :
1131 : #define locks_inode(f) file_inode(f)
1132 :
1133 : #ifdef CONFIG_FILE_LOCKING
1134 : extern int fcntl_getlk(struct file *, unsigned int, struct flock *);
1135 : extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
1136 : struct flock *);
1137 :
1138 : #if BITS_PER_LONG == 32
1139 : extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 *);
1140 : extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
1141 : struct flock64 *);
1142 : #endif
1143 :
1144 : extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
1145 : extern int fcntl_getlease(struct file *filp);
1146 :
1147 : /* fs/locks.c */
1148 : void locks_free_lock_context(struct inode *inode);
1149 : void locks_free_lock(struct file_lock *fl);
1150 : extern void locks_init_lock(struct file_lock *);
1151 : extern struct file_lock * locks_alloc_lock(void);
1152 : extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1153 : extern void locks_copy_conflock(struct file_lock *, struct file_lock *);
1154 : extern void locks_remove_posix(struct file *, fl_owner_t);
1155 : extern void locks_remove_file(struct file *);
1156 : extern void locks_release_private(struct file_lock *);
1157 : extern void posix_test_lock(struct file *, struct file_lock *);
1158 : extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
1159 : extern int locks_delete_block(struct file_lock *);
1160 : extern int vfs_test_lock(struct file *, struct file_lock *);
1161 : extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
1162 : extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
1163 : extern int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl);
1164 : extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
1165 : extern void lease_get_mtime(struct inode *, struct timespec64 *time);
1166 : extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
1167 : extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
1168 : extern int lease_modify(struct file_lock *, int, struct list_head *);
1169 :
1170 : struct notifier_block;
1171 : extern int lease_register_notifier(struct notifier_block *);
1172 : extern void lease_unregister_notifier(struct notifier_block *);
1173 :
1174 : struct files_struct;
1175 : extern void show_fd_locks(struct seq_file *f,
1176 : struct file *filp, struct files_struct *files);
1177 : #else /* !CONFIG_FILE_LOCKING */
1178 : static inline int fcntl_getlk(struct file *file, unsigned int cmd,
1179 : struct flock __user *user)
1180 : {
1181 : return -EINVAL;
1182 : }
1183 :
1184 : static inline int fcntl_setlk(unsigned int fd, struct file *file,
1185 : unsigned int cmd, struct flock __user *user)
1186 : {
1187 : return -EACCES;
1188 : }
1189 :
1190 : #if BITS_PER_LONG == 32
1191 : static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
1192 : struct flock64 *user)
1193 : {
1194 : return -EINVAL;
1195 : }
1196 :
1197 : static inline int fcntl_setlk64(unsigned int fd, struct file *file,
1198 : unsigned int cmd, struct flock64 *user)
1199 : {
1200 : return -EACCES;
1201 : }
1202 : #endif
1203 : static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
1204 : {
1205 : return -EINVAL;
1206 : }
1207 :
1208 : static inline int fcntl_getlease(struct file *filp)
1209 : {
1210 : return F_UNLCK;
1211 : }
1212 :
1213 : static inline void
1214 : locks_free_lock_context(struct inode *inode)
1215 : {
1216 : }
1217 :
1218 : static inline void locks_init_lock(struct file_lock *fl)
1219 : {
1220 : return;
1221 : }
1222 :
1223 : static inline void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
1224 : {
1225 : return;
1226 : }
1227 :
1228 : static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1229 : {
1230 : return;
1231 : }
1232 :
1233 : static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
1234 : {
1235 : return;
1236 : }
1237 :
1238 : static inline void locks_remove_file(struct file *filp)
1239 : {
1240 : return;
1241 : }
1242 :
1243 : static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
1244 : {
1245 : return;
1246 : }
1247 :
1248 : static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
1249 : struct file_lock *conflock)
1250 : {
1251 : return -ENOLCK;
1252 : }
1253 :
1254 : static inline int locks_delete_block(struct file_lock *waiter)
1255 : {
1256 : return -ENOENT;
1257 : }
1258 :
1259 : static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
1260 : {
1261 : return 0;
1262 : }
1263 :
1264 : static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
1265 : struct file_lock *fl, struct file_lock *conf)
1266 : {
1267 : return -ENOLCK;
1268 : }
1269 :
1270 : static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
1271 : {
1272 : return 0;
1273 : }
1274 :
1275 : static inline int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl)
1276 : {
1277 : return -ENOLCK;
1278 : }
1279 :
1280 : static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
1281 : {
1282 : return 0;
1283 : }
1284 :
1285 : static inline void lease_get_mtime(struct inode *inode,
1286 : struct timespec64 *time)
1287 : {
1288 : return;
1289 : }
1290 :
1291 : static inline int generic_setlease(struct file *filp, long arg,
1292 : struct file_lock **flp, void **priv)
1293 : {
1294 : return -EINVAL;
1295 : }
1296 :
1297 : static inline int vfs_setlease(struct file *filp, long arg,
1298 : struct file_lock **lease, void **priv)
1299 : {
1300 : return -EINVAL;
1301 : }
1302 :
1303 : static inline int lease_modify(struct file_lock *fl, int arg,
1304 : struct list_head *dispose)
1305 : {
1306 : return -EINVAL;
1307 : }
1308 :
1309 : struct files_struct;
1310 : static inline void show_fd_locks(struct seq_file *f,
1311 : struct file *filp, struct files_struct *files) {}
1312 : #endif /* !CONFIG_FILE_LOCKING */
1313 :
1314 : static inline struct inode *file_inode(const struct file *f)
1315 : {
1316 : return f->f_inode;
1317 : }
1318 :
1319 : static inline struct dentry *file_dentry(const struct file *file)
1320 : {
1321 0 : return d_real(file->f_path.dentry, file_inode(file));
1322 : }
1323 :
1324 : static inline int locks_lock_file_wait(struct file *filp, struct file_lock *fl)
1325 : {
1326 0 : return locks_lock_inode_wait(locks_inode(filp), fl);
1327 : }
1328 :
1329 : struct fasync_struct {
1330 : rwlock_t fa_lock;
1331 : int magic;
1332 : int fa_fd;
1333 : struct fasync_struct *fa_next; /* singly linked list */
1334 : struct file *fa_file;
1335 : struct rcu_head fa_rcu;
1336 : };
1337 :
1338 : #define FASYNC_MAGIC 0x4601
1339 :
1340 : /* SMP safe fasync helpers: */
1341 : extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1342 : extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1343 : extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1344 : extern struct fasync_struct *fasync_alloc(void);
1345 : extern void fasync_free(struct fasync_struct *);
1346 :
1347 : /* can be called from interrupts */
1348 : extern void kill_fasync(struct fasync_struct **, int, int);
1349 :
1350 : extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1351 : extern int f_setown(struct file *filp, unsigned long arg, int force);
1352 : extern void f_delown(struct file *filp);
1353 : extern pid_t f_getown(struct file *filp);
1354 : extern int send_sigurg(struct fown_struct *fown);
1355 :
1356 : /*
1357 : * sb->s_flags. Note that these mirror the equivalent MS_* flags where
1358 : * represented in both.
1359 : */
1360 : #define SB_RDONLY 1 /* Mount read-only */
1361 : #define SB_NOSUID 2 /* Ignore suid and sgid bits */
1362 : #define SB_NODEV 4 /* Disallow access to device special files */
1363 : #define SB_NOEXEC 8 /* Disallow program execution */
1364 : #define SB_SYNCHRONOUS 16 /* Writes are synced at once */
1365 : #define SB_MANDLOCK 64 /* Allow mandatory locks on an FS */
1366 : #define SB_DIRSYNC 128 /* Directory modifications are synchronous */
1367 : #define SB_NOATIME 1024 /* Do not update access times. */
1368 : #define SB_NODIRATIME 2048 /* Do not update directory access times */
1369 : #define SB_SILENT 32768
1370 : #define SB_POSIXACL (1<<16) /* VFS does not apply the umask */
1371 : #define SB_INLINECRYPT (1<<17) /* Use blk-crypto for encrypted files */
1372 : #define SB_KERNMOUNT (1<<22) /* this is a kern_mount call */
1373 : #define SB_I_VERSION (1<<23) /* Update inode I_version field */
1374 : #define SB_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */
1375 :
1376 : /* These sb flags are internal to the kernel */
1377 : #define SB_SUBMOUNT (1<<26)
1378 : #define SB_FORCE (1<<27)
1379 : #define SB_NOSEC (1<<28)
1380 : #define SB_BORN (1<<29)
1381 : #define SB_ACTIVE (1<<30)
1382 : #define SB_NOUSER (1<<31)
1383 :
1384 : /* These flags relate to encoding and casefolding */
1385 : #define SB_ENC_STRICT_MODE_FL (1 << 0)
1386 :
1387 : #define sb_has_strict_encoding(sb) \
1388 : (sb->s_encoding_flags & SB_ENC_STRICT_MODE_FL)
1389 :
1390 : /*
1391 : * Umount options
1392 : */
1393 :
1394 : #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1395 : #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1396 : #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1397 : #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1398 : #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1399 :
1400 : /* sb->s_iflags */
1401 : #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1402 : #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1403 : #define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
1404 : #define SB_I_STABLE_WRITES 0x00000008 /* don't modify blks until WB is done */
1405 :
1406 : /* sb->s_iflags to limit user namespace mounts */
1407 : #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
1408 : #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
1409 : #define SB_I_UNTRUSTED_MOUNTER 0x00000040
1410 :
1411 : #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */
1412 : #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */
1413 : #define SB_I_TS_EXPIRY_WARNED 0x00000400 /* warned about timestamp range expiry */
1414 :
1415 : /* Possible states of 'frozen' field */
1416 : enum {
1417 : SB_UNFROZEN = 0, /* FS is unfrozen */
1418 : SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1419 : SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1420 : SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1421 : * internal threads if needed) */
1422 : SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1423 : };
1424 :
1425 : #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1426 :
1427 : struct sb_writers {
1428 : int frozen; /* Is sb frozen? */
1429 : wait_queue_head_t wait_unfrozen; /* wait for thaw */
1430 : struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
1431 : };
1432 :
1433 : struct super_block {
1434 : struct list_head s_list; /* Keep this first */
1435 : dev_t s_dev; /* search index; _not_ kdev_t */
1436 : unsigned char s_blocksize_bits;
1437 : unsigned long s_blocksize;
1438 : loff_t s_maxbytes; /* Max file size */
1439 : struct file_system_type *s_type;
1440 : const struct super_operations *s_op;
1441 : const struct dquot_operations *dq_op;
1442 : const struct quotactl_ops *s_qcop;
1443 : const struct export_operations *s_export_op;
1444 : unsigned long s_flags;
1445 : unsigned long s_iflags; /* internal SB_I_* flags */
1446 : unsigned long s_magic;
1447 : struct dentry *s_root;
1448 : struct rw_semaphore s_umount;
1449 : int s_count;
1450 : atomic_t s_active;
1451 : #ifdef CONFIG_SECURITY
1452 : void *s_security;
1453 : #endif
1454 : const struct xattr_handler **s_xattr;
1455 : #ifdef CONFIG_FS_ENCRYPTION
1456 : const struct fscrypt_operations *s_cop;
1457 : struct key *s_master_keys; /* master crypto keys in use */
1458 : #endif
1459 : #ifdef CONFIG_FS_VERITY
1460 : const struct fsverity_operations *s_vop;
1461 : #endif
1462 : #if IS_ENABLED(CONFIG_UNICODE)
1463 : struct unicode_map *s_encoding;
1464 : __u16 s_encoding_flags;
1465 : #endif
1466 : struct hlist_bl_head s_roots; /* alternate root dentries for NFS */
1467 : struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1468 : struct block_device *s_bdev;
1469 : struct backing_dev_info *s_bdi;
1470 : struct mtd_info *s_mtd;
1471 : struct hlist_node s_instances;
1472 : unsigned int s_quota_types; /* Bitmask of supported quota types */
1473 : struct quota_info s_dquot; /* Diskquota specific options */
1474 :
1475 : struct sb_writers s_writers;
1476 :
1477 : /*
1478 : * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
1479 : * s_fsnotify_marks together for cache efficiency. They are frequently
1480 : * accessed and rarely modified.
1481 : */
1482 : void *s_fs_info; /* Filesystem private info */
1483 :
1484 : /* Granularity of c/m/atime in ns (cannot be worse than a second) */
1485 : u32 s_time_gran;
1486 : /* Time limits for c/m/atime in seconds */
1487 : time64_t s_time_min;
1488 : time64_t s_time_max;
1489 : #ifdef CONFIG_FSNOTIFY
1490 : __u32 s_fsnotify_mask;
1491 : struct fsnotify_mark_connector __rcu *s_fsnotify_marks;
1492 : #endif
1493 :
1494 : char s_id[32]; /* Informational name */
1495 : uuid_t s_uuid; /* UUID */
1496 :
1497 : unsigned int s_max_links;
1498 : fmode_t s_mode;
1499 :
1500 : /*
1501 : * The next field is for VFS *only*. No filesystems have any business
1502 : * even looking at it. You had been warned.
1503 : */
1504 : struct mutex s_vfs_rename_mutex; /* Kludge */
1505 :
1506 : /*
1507 : * Filesystem subtype. If non-empty the filesystem type field
1508 : * in /proc/mounts will be "type.subtype"
1509 : */
1510 : const char *s_subtype;
1511 :
1512 : const struct dentry_operations *s_d_op; /* default d_op for dentries */
1513 :
1514 : struct shrinker s_shrink; /* per-sb shrinker handle */
1515 :
1516 : /* Number of inodes with nlink == 0 but still referenced */
1517 : atomic_long_t s_remove_count;
1518 :
1519 : /*
1520 : * Number of inode/mount/sb objects that are being watched, note that
1521 : * inodes objects are currently double-accounted.
1522 : */
1523 : atomic_long_t s_fsnotify_connectors;
1524 :
1525 : /* Being remounted read-only */
1526 : int s_readonly_remount;
1527 :
1528 : /* per-sb errseq_t for reporting writeback errors via syncfs */
1529 : errseq_t s_wb_err;
1530 :
1531 : /* AIO completions deferred from interrupt context */
1532 : struct workqueue_struct *s_dio_done_wq;
1533 : struct hlist_head s_pins;
1534 :
1535 : /*
1536 : * Owning user namespace and default context in which to
1537 : * interpret filesystem uids, gids, quotas, device nodes,
1538 : * xattrs and security labels.
1539 : */
1540 : struct user_namespace *s_user_ns;
1541 :
1542 : /*
1543 : * The list_lru structure is essentially just a pointer to a table
1544 : * of per-node lru lists, each of which has its own spinlock.
1545 : * There is no need to put them into separate cachelines.
1546 : */
1547 : struct list_lru s_dentry_lru;
1548 : struct list_lru s_inode_lru;
1549 : struct rcu_head rcu;
1550 : struct work_struct destroy_work;
1551 :
1552 : struct mutex s_sync_lock; /* sync serialisation lock */
1553 :
1554 : /*
1555 : * Indicates how deep in a filesystem stack this SB is
1556 : */
1557 : int s_stack_depth;
1558 :
1559 : /* s_inode_list_lock protects s_inodes */
1560 : spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
1561 : struct list_head s_inodes; /* all inodes */
1562 :
1563 : spinlock_t s_inode_wblist_lock;
1564 : struct list_head s_inodes_wb; /* writeback inodes */
1565 : } __randomize_layout;
1566 :
1567 : static inline struct user_namespace *i_user_ns(const struct inode *inode)
1568 : {
1569 23 : return inode->i_sb->s_user_ns;
1570 : }
1571 :
1572 : /* Helper functions so that in most cases filesystems will
1573 : * not need to deal directly with kuid_t and kgid_t and can
1574 : * instead deal with the raw numeric values that are stored
1575 : * in the filesystem.
1576 : */
1577 : static inline uid_t i_uid_read(const struct inode *inode)
1578 : {
1579 : return from_kuid(i_user_ns(inode), inode->i_uid);
1580 : }
1581 :
1582 : static inline gid_t i_gid_read(const struct inode *inode)
1583 : {
1584 : return from_kgid(i_user_ns(inode), inode->i_gid);
1585 : }
1586 :
1587 : static inline void i_uid_write(struct inode *inode, uid_t uid)
1588 : {
1589 17 : inode->i_uid = make_kuid(i_user_ns(inode), uid);
1590 : }
1591 :
1592 : static inline void i_gid_write(struct inode *inode, gid_t gid)
1593 : {
1594 17 : inode->i_gid = make_kgid(i_user_ns(inode), gid);
1595 : }
1596 :
1597 : /**
1598 : * i_uid_into_mnt - map an inode's i_uid down into a mnt_userns
1599 : * @mnt_userns: user namespace of the mount the inode was found from
1600 : * @inode: inode to map
1601 : *
1602 : * Return: the inode's i_uid mapped down according to @mnt_userns.
1603 : * If the inode's i_uid has no mapping INVALID_UID is returned.
1604 : */
1605 : static inline kuid_t i_uid_into_mnt(struct user_namespace *mnt_userns,
1606 : const struct inode *inode)
1607 : {
1608 39 : return mapped_kuid_fs(mnt_userns, i_user_ns(inode), inode->i_uid);
1609 : }
1610 :
1611 : /**
1612 : * i_gid_into_mnt - map an inode's i_gid down into a mnt_userns
1613 : * @mnt_userns: user namespace of the mount the inode was found from
1614 : * @inode: inode to map
1615 : *
1616 : * Return: the inode's i_gid mapped down according to @mnt_userns.
1617 : * If the inode's i_gid has no mapping INVALID_GID is returned.
1618 : */
1619 : static inline kgid_t i_gid_into_mnt(struct user_namespace *mnt_userns,
1620 : const struct inode *inode)
1621 : {
1622 6 : return mapped_kgid_fs(mnt_userns, i_user_ns(inode), inode->i_gid);
1623 : }
1624 :
1625 : /**
1626 : * inode_fsuid_set - initialize inode's i_uid field with callers fsuid
1627 : * @inode: inode to initialize
1628 : * @mnt_userns: user namespace of the mount the inode was found from
1629 : *
1630 : * Initialize the i_uid field of @inode. If the inode was found/created via
1631 : * an idmapped mount map the caller's fsuid according to @mnt_users.
1632 : */
1633 : static inline void inode_fsuid_set(struct inode *inode,
1634 : struct user_namespace *mnt_userns)
1635 : {
1636 15 : inode->i_uid = mapped_fsuid(mnt_userns, i_user_ns(inode));
1637 : }
1638 :
1639 : /**
1640 : * inode_fsgid_set - initialize inode's i_gid field with callers fsgid
1641 : * @inode: inode to initialize
1642 : * @mnt_userns: user namespace of the mount the inode was found from
1643 : *
1644 : * Initialize the i_gid field of @inode. If the inode was found/created via
1645 : * an idmapped mount map the caller's fsgid according to @mnt_users.
1646 : */
1647 : static inline void inode_fsgid_set(struct inode *inode,
1648 : struct user_namespace *mnt_userns)
1649 : {
1650 15 : inode->i_gid = mapped_fsgid(mnt_userns, i_user_ns(inode));
1651 : }
1652 :
1653 : /**
1654 : * fsuidgid_has_mapping() - check whether caller's fsuid/fsgid is mapped
1655 : * @sb: the superblock we want a mapping in
1656 : * @mnt_userns: user namespace of the relevant mount
1657 : *
1658 : * Check whether the caller's fsuid and fsgid have a valid mapping in the
1659 : * s_user_ns of the superblock @sb. If the caller is on an idmapped mount map
1660 : * the caller's fsuid and fsgid according to the @mnt_userns first.
1661 : *
1662 : * Return: true if fsuid and fsgid is mapped, false if not.
1663 : */
1664 3 : static inline bool fsuidgid_has_mapping(struct super_block *sb,
1665 : struct user_namespace *mnt_userns)
1666 : {
1667 3 : struct user_namespace *fs_userns = sb->s_user_ns;
1668 : kuid_t kuid;
1669 : kgid_t kgid;
1670 :
1671 3 : kuid = mapped_fsuid(mnt_userns, fs_userns);
1672 3 : if (!uid_valid(kuid))
1673 : return false;
1674 3 : kgid = mapped_fsgid(mnt_userns, fs_userns);
1675 3 : if (!gid_valid(kgid))
1676 : return false;
1677 : return kuid_has_mapping(fs_userns, kuid) &&
1678 : kgid_has_mapping(fs_userns, kgid);
1679 : }
1680 :
1681 : extern struct timespec64 current_time(struct inode *inode);
1682 :
1683 : /*
1684 : * Snapshotting support.
1685 : */
1686 :
1687 : /*
1688 : * These are internal functions, please use sb_start_{write,pagefault,intwrite}
1689 : * instead.
1690 : */
1691 : static inline void __sb_end_write(struct super_block *sb, int level)
1692 : {
1693 3 : percpu_up_read(sb->s_writers.rw_sem + level-1);
1694 : }
1695 :
1696 : static inline void __sb_start_write(struct super_block *sb, int level)
1697 : {
1698 3 : percpu_down_read(sb->s_writers.rw_sem + level - 1);
1699 : }
1700 :
1701 : static inline bool __sb_start_write_trylock(struct super_block *sb, int level)
1702 : {
1703 0 : return percpu_down_read_trylock(sb->s_writers.rw_sem + level - 1);
1704 : }
1705 :
1706 : #define __sb_writers_acquired(sb, lev) \
1707 : percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1708 : #define __sb_writers_release(sb, lev) \
1709 : percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1710 :
1711 : /**
1712 : * sb_end_write - drop write access to a superblock
1713 : * @sb: the super we wrote to
1714 : *
1715 : * Decrement number of writers to the filesystem. Wake up possible waiters
1716 : * wanting to freeze the filesystem.
1717 : */
1718 : static inline void sb_end_write(struct super_block *sb)
1719 : {
1720 3 : __sb_end_write(sb, SB_FREEZE_WRITE);
1721 : }
1722 :
1723 : /**
1724 : * sb_end_pagefault - drop write access to a superblock from a page fault
1725 : * @sb: the super we wrote to
1726 : *
1727 : * Decrement number of processes handling write page fault to the filesystem.
1728 : * Wake up possible waiters wanting to freeze the filesystem.
1729 : */
1730 : static inline void sb_end_pagefault(struct super_block *sb)
1731 : {
1732 0 : __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1733 : }
1734 :
1735 : /**
1736 : * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1737 : * @sb: the super we wrote to
1738 : *
1739 : * Decrement fs-internal number of writers to the filesystem. Wake up possible
1740 : * waiters wanting to freeze the filesystem.
1741 : */
1742 : static inline void sb_end_intwrite(struct super_block *sb)
1743 : {
1744 : __sb_end_write(sb, SB_FREEZE_FS);
1745 : }
1746 :
1747 : /**
1748 : * sb_start_write - get write access to a superblock
1749 : * @sb: the super we write to
1750 : *
1751 : * When a process wants to write data or metadata to a file system (i.e. dirty
1752 : * a page or an inode), it should embed the operation in a sb_start_write() -
1753 : * sb_end_write() pair to get exclusion against file system freezing. This
1754 : * function increments number of writers preventing freezing. If the file
1755 : * system is already frozen, the function waits until the file system is
1756 : * thawed.
1757 : *
1758 : * Since freeze protection behaves as a lock, users have to preserve
1759 : * ordering of freeze protection and other filesystem locks. Generally,
1760 : * freeze protection should be the outermost lock. In particular, we have:
1761 : *
1762 : * sb_start_write
1763 : * -> i_mutex (write path, truncate, directory ops, ...)
1764 : * -> s_umount (freeze_super, thaw_super)
1765 : */
1766 : static inline void sb_start_write(struct super_block *sb)
1767 : {
1768 3 : __sb_start_write(sb, SB_FREEZE_WRITE);
1769 : }
1770 :
1771 : static inline bool sb_start_write_trylock(struct super_block *sb)
1772 : {
1773 0 : return __sb_start_write_trylock(sb, SB_FREEZE_WRITE);
1774 : }
1775 :
1776 : /**
1777 : * sb_start_pagefault - get write access to a superblock from a page fault
1778 : * @sb: the super we write to
1779 : *
1780 : * When a process starts handling write page fault, it should embed the
1781 : * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1782 : * exclusion against file system freezing. This is needed since the page fault
1783 : * is going to dirty a page. This function increments number of running page
1784 : * faults preventing freezing. If the file system is already frozen, the
1785 : * function waits until the file system is thawed.
1786 : *
1787 : * Since page fault freeze protection behaves as a lock, users have to preserve
1788 : * ordering of freeze protection and other filesystem locks. It is advised to
1789 : * put sb_start_pagefault() close to mmap_lock in lock ordering. Page fault
1790 : * handling code implies lock dependency:
1791 : *
1792 : * mmap_lock
1793 : * -> sb_start_pagefault
1794 : */
1795 : static inline void sb_start_pagefault(struct super_block *sb)
1796 : {
1797 0 : __sb_start_write(sb, SB_FREEZE_PAGEFAULT);
1798 : }
1799 :
1800 : /**
1801 : * sb_start_intwrite - get write access to a superblock for internal fs purposes
1802 : * @sb: the super we write to
1803 : *
1804 : * This is the third level of protection against filesystem freezing. It is
1805 : * free for use by a filesystem. The only requirement is that it must rank
1806 : * below sb_start_pagefault.
1807 : *
1808 : * For example filesystem can call sb_start_intwrite() when starting a
1809 : * transaction which somewhat eases handling of freezing for internal sources
1810 : * of filesystem changes (internal fs threads, discarding preallocation on file
1811 : * close, etc.).
1812 : */
1813 : static inline void sb_start_intwrite(struct super_block *sb)
1814 : {
1815 : __sb_start_write(sb, SB_FREEZE_FS);
1816 : }
1817 :
1818 : static inline bool sb_start_intwrite_trylock(struct super_block *sb)
1819 : {
1820 : return __sb_start_write_trylock(sb, SB_FREEZE_FS);
1821 : }
1822 :
1823 : bool inode_owner_or_capable(struct user_namespace *mnt_userns,
1824 : const struct inode *inode);
1825 :
1826 : /*
1827 : * VFS helper functions..
1828 : */
1829 : int vfs_create(struct user_namespace *, struct inode *,
1830 : struct dentry *, umode_t, bool);
1831 : int vfs_mkdir(struct user_namespace *, struct inode *,
1832 : struct dentry *, umode_t);
1833 : int vfs_mknod(struct user_namespace *, struct inode *, struct dentry *,
1834 : umode_t, dev_t);
1835 : int vfs_symlink(struct user_namespace *, struct inode *,
1836 : struct dentry *, const char *);
1837 : int vfs_link(struct dentry *, struct user_namespace *, struct inode *,
1838 : struct dentry *, struct inode **);
1839 : int vfs_rmdir(struct user_namespace *, struct inode *, struct dentry *);
1840 : int vfs_unlink(struct user_namespace *, struct inode *, struct dentry *,
1841 : struct inode **);
1842 :
1843 : /**
1844 : * struct renamedata - contains all information required for renaming
1845 : * @old_mnt_userns: old user namespace of the mount the inode was found from
1846 : * @old_dir: parent of source
1847 : * @old_dentry: source
1848 : * @new_mnt_userns: new user namespace of the mount the inode was found from
1849 : * @new_dir: parent of destination
1850 : * @new_dentry: destination
1851 : * @delegated_inode: returns an inode needing a delegation break
1852 : * @flags: rename flags
1853 : */
1854 : struct renamedata {
1855 : struct user_namespace *old_mnt_userns;
1856 : struct inode *old_dir;
1857 : struct dentry *old_dentry;
1858 : struct user_namespace *new_mnt_userns;
1859 : struct inode *new_dir;
1860 : struct dentry *new_dentry;
1861 : struct inode **delegated_inode;
1862 : unsigned int flags;
1863 : } __randomize_layout;
1864 :
1865 : int vfs_rename(struct renamedata *);
1866 :
1867 : static inline int vfs_whiteout(struct user_namespace *mnt_userns,
1868 : struct inode *dir, struct dentry *dentry)
1869 : {
1870 : return vfs_mknod(mnt_userns, dir, dentry, S_IFCHR | WHITEOUT_MODE,
1871 : WHITEOUT_DEV);
1872 : }
1873 :
1874 : struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns,
1875 : struct dentry *dentry, umode_t mode, int open_flag);
1876 :
1877 : int vfs_mkobj(struct dentry *, umode_t,
1878 : int (*f)(struct dentry *, umode_t, void *),
1879 : void *);
1880 :
1881 : int vfs_fchown(struct file *file, uid_t user, gid_t group);
1882 : int vfs_fchmod(struct file *file, umode_t mode);
1883 : int vfs_utimes(const struct path *path, struct timespec64 *times);
1884 :
1885 : extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1886 :
1887 : #ifdef CONFIG_COMPAT
1888 : extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
1889 : unsigned long arg);
1890 : #else
1891 : #define compat_ptr_ioctl NULL
1892 : #endif
1893 :
1894 : /*
1895 : * VFS file helper functions.
1896 : */
1897 : void inode_init_owner(struct user_namespace *mnt_userns, struct inode *inode,
1898 : const struct inode *dir, umode_t mode);
1899 : extern bool may_open_dev(const struct path *path);
1900 :
1901 : /*
1902 : * This is the "filldir" function type, used by readdir() to let
1903 : * the kernel specify what kind of dirent layout it wants to have.
1904 : * This allows the kernel to read directories into kernel space or
1905 : * to have different dirent layouts depending on the binary type.
1906 : */
1907 : struct dir_context;
1908 : typedef int (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
1909 : unsigned);
1910 :
1911 : struct dir_context {
1912 : filldir_t actor;
1913 : loff_t pos;
1914 : };
1915 :
1916 : /*
1917 : * These flags let !MMU mmap() govern direct device mapping vs immediate
1918 : * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1919 : *
1920 : * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1921 : * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1922 : * NOMMU_MAP_READ: Can be mapped for reading
1923 : * NOMMU_MAP_WRITE: Can be mapped for writing
1924 : * NOMMU_MAP_EXEC: Can be mapped for execution
1925 : */
1926 : #define NOMMU_MAP_COPY 0x00000001
1927 : #define NOMMU_MAP_DIRECT 0x00000008
1928 : #define NOMMU_MAP_READ VM_MAYREAD
1929 : #define NOMMU_MAP_WRITE VM_MAYWRITE
1930 : #define NOMMU_MAP_EXEC VM_MAYEXEC
1931 :
1932 : #define NOMMU_VMFLAGS \
1933 : (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1934 :
1935 : /*
1936 : * These flags control the behavior of the remap_file_range function pointer.
1937 : * If it is called with len == 0 that means "remap to end of source file".
1938 : * See Documentation/filesystems/vfs.rst for more details about this call.
1939 : *
1940 : * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate)
1941 : * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request
1942 : */
1943 : #define REMAP_FILE_DEDUP (1 << 0)
1944 : #define REMAP_FILE_CAN_SHORTEN (1 << 1)
1945 :
1946 : /*
1947 : * These flags signal that the caller is ok with altering various aspects of
1948 : * the behavior of the remap operation. The changes must be made by the
1949 : * implementation; the vfs remap helper functions can take advantage of them.
1950 : * Flags in this category exist to preserve the quirky behavior of the hoisted
1951 : * btrfs clone/dedupe ioctls.
1952 : */
1953 : #define REMAP_FILE_ADVISORY (REMAP_FILE_CAN_SHORTEN)
1954 :
1955 : struct iov_iter;
1956 :
1957 : struct file_operations {
1958 : struct module *owner;
1959 : loff_t (*llseek) (struct file *, loff_t, int);
1960 : ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1961 : ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1962 : ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1963 : ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1964 : int (*iopoll)(struct kiocb *kiocb, struct io_comp_batch *,
1965 : unsigned int flags);
1966 : int (*iterate) (struct file *, struct dir_context *);
1967 : int (*iterate_shared) (struct file *, struct dir_context *);
1968 : __poll_t (*poll) (struct file *, struct poll_table_struct *);
1969 : long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1970 : long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1971 : int (*mmap) (struct file *, struct vm_area_struct *);
1972 : unsigned long mmap_supported_flags;
1973 : int (*open) (struct inode *, struct file *);
1974 : int (*flush) (struct file *, fl_owner_t id);
1975 : int (*release) (struct inode *, struct file *);
1976 : int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1977 : int (*fasync) (int, struct file *, int);
1978 : int (*lock) (struct file *, int, struct file_lock *);
1979 : ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1980 : unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1981 : int (*check_flags)(int);
1982 : int (*flock) (struct file *, int, struct file_lock *);
1983 : ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1984 : ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1985 : int (*setlease)(struct file *, long, struct file_lock **, void **);
1986 : long (*fallocate)(struct file *file, int mode, loff_t offset,
1987 : loff_t len);
1988 : void (*show_fdinfo)(struct seq_file *m, struct file *f);
1989 : #ifndef CONFIG_MMU
1990 : unsigned (*mmap_capabilities)(struct file *);
1991 : #endif
1992 : ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
1993 : loff_t, size_t, unsigned int);
1994 : loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
1995 : struct file *file_out, loff_t pos_out,
1996 : loff_t len, unsigned int remap_flags);
1997 : int (*fadvise)(struct file *, loff_t, loff_t, int);
1998 : } __randomize_layout;
1999 :
2000 : struct inode_operations {
2001 : struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
2002 : const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
2003 : int (*permission) (struct user_namespace *, struct inode *, int);
2004 : struct posix_acl * (*get_acl)(struct inode *, int, bool);
2005 :
2006 : int (*readlink) (struct dentry *, char __user *,int);
2007 :
2008 : int (*create) (struct user_namespace *, struct inode *,struct dentry *,
2009 : umode_t, bool);
2010 : int (*link) (struct dentry *,struct inode *,struct dentry *);
2011 : int (*unlink) (struct inode *,struct dentry *);
2012 : int (*symlink) (struct user_namespace *, struct inode *,struct dentry *,
2013 : const char *);
2014 : int (*mkdir) (struct user_namespace *, struct inode *,struct dentry *,
2015 : umode_t);
2016 : int (*rmdir) (struct inode *,struct dentry *);
2017 : int (*mknod) (struct user_namespace *, struct inode *,struct dentry *,
2018 : umode_t,dev_t);
2019 : int (*rename) (struct user_namespace *, struct inode *, struct dentry *,
2020 : struct inode *, struct dentry *, unsigned int);
2021 : int (*setattr) (struct user_namespace *, struct dentry *,
2022 : struct iattr *);
2023 : int (*getattr) (struct user_namespace *, const struct path *,
2024 : struct kstat *, u32, unsigned int);
2025 : ssize_t (*listxattr) (struct dentry *, char *, size_t);
2026 : int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
2027 : u64 len);
2028 : int (*update_time)(struct inode *, struct timespec64 *, int);
2029 : int (*atomic_open)(struct inode *, struct dentry *,
2030 : struct file *, unsigned open_flag,
2031 : umode_t create_mode);
2032 : int (*tmpfile) (struct user_namespace *, struct inode *,
2033 : struct dentry *, umode_t);
2034 : int (*set_acl)(struct user_namespace *, struct inode *,
2035 : struct posix_acl *, int);
2036 : int (*fileattr_set)(struct user_namespace *mnt_userns,
2037 : struct dentry *dentry, struct fileattr *fa);
2038 : int (*fileattr_get)(struct dentry *dentry, struct fileattr *fa);
2039 : } ____cacheline_aligned;
2040 :
2041 : static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
2042 : struct iov_iter *iter)
2043 : {
2044 0 : return file->f_op->read_iter(kio, iter);
2045 : }
2046 :
2047 : static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
2048 : struct iov_iter *iter)
2049 : {
2050 0 : return file->f_op->write_iter(kio, iter);
2051 : }
2052 :
2053 : static inline int call_mmap(struct file *file, struct vm_area_struct *vma)
2054 : {
2055 0 : return file->f_op->mmap(file, vma);
2056 : }
2057 :
2058 : extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
2059 : extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
2060 : extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
2061 : loff_t, size_t, unsigned int);
2062 : extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in,
2063 : struct file *file_out, loff_t pos_out,
2064 : size_t len, unsigned int flags);
2065 : extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
2066 : struct file *file_out, loff_t pos_out,
2067 : loff_t *count,
2068 : unsigned int remap_flags);
2069 : extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
2070 : struct file *file_out, loff_t pos_out,
2071 : loff_t len, unsigned int remap_flags);
2072 : extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
2073 : struct file *file_out, loff_t pos_out,
2074 : loff_t len, unsigned int remap_flags);
2075 : extern int vfs_dedupe_file_range(struct file *file,
2076 : struct file_dedupe_range *same);
2077 : extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
2078 : struct file *dst_file, loff_t dst_pos,
2079 : loff_t len, unsigned int remap_flags);
2080 :
2081 :
2082 : struct super_operations {
2083 : struct inode *(*alloc_inode)(struct super_block *sb);
2084 : void (*destroy_inode)(struct inode *);
2085 : void (*free_inode)(struct inode *);
2086 :
2087 : void (*dirty_inode) (struct inode *, int flags);
2088 : int (*write_inode) (struct inode *, struct writeback_control *wbc);
2089 : int (*drop_inode) (struct inode *);
2090 : void (*evict_inode) (struct inode *);
2091 : void (*put_super) (struct super_block *);
2092 : int (*sync_fs)(struct super_block *sb, int wait);
2093 : int (*freeze_super) (struct super_block *);
2094 : int (*freeze_fs) (struct super_block *);
2095 : int (*thaw_super) (struct super_block *);
2096 : int (*unfreeze_fs) (struct super_block *);
2097 : int (*statfs) (struct dentry *, struct kstatfs *);
2098 : int (*remount_fs) (struct super_block *, int *, char *);
2099 : void (*umount_begin) (struct super_block *);
2100 :
2101 : int (*show_options)(struct seq_file *, struct dentry *);
2102 : int (*show_devname)(struct seq_file *, struct dentry *);
2103 : int (*show_path)(struct seq_file *, struct dentry *);
2104 : int (*show_stats)(struct seq_file *, struct dentry *);
2105 : #ifdef CONFIG_QUOTA
2106 : ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
2107 : ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
2108 : struct dquot **(*get_dquots)(struct inode *);
2109 : #endif
2110 : long (*nr_cached_objects)(struct super_block *,
2111 : struct shrink_control *);
2112 : long (*free_cached_objects)(struct super_block *,
2113 : struct shrink_control *);
2114 : };
2115 :
2116 : /*
2117 : * Inode flags - they have no relation to superblock flags now
2118 : */
2119 : #define S_SYNC (1 << 0) /* Writes are synced at once */
2120 : #define S_NOATIME (1 << 1) /* Do not update access times */
2121 : #define S_APPEND (1 << 2) /* Append-only file */
2122 : #define S_IMMUTABLE (1 << 3) /* Immutable file */
2123 : #define S_DEAD (1 << 4) /* removed, but still open directory */
2124 : #define S_NOQUOTA (1 << 5) /* Inode is not counted to quota */
2125 : #define S_DIRSYNC (1 << 6) /* Directory modifications are synchronous */
2126 : #define S_NOCMTIME (1 << 7) /* Do not update file c/mtime */
2127 : #define S_SWAPFILE (1 << 8) /* Do not truncate: swapon got its bmaps */
2128 : #define S_PRIVATE (1 << 9) /* Inode is fs-internal */
2129 : #define S_IMA (1 << 10) /* Inode has an associated IMA struct */
2130 : #define S_AUTOMOUNT (1 << 11) /* Automount/referral quasi-directory */
2131 : #define S_NOSEC (1 << 12) /* no suid or xattr security attributes */
2132 : #ifdef CONFIG_FS_DAX
2133 : #define S_DAX (1 << 13) /* Direct Access, avoiding the page cache */
2134 : #else
2135 : #define S_DAX 0 /* Make all the DAX code disappear */
2136 : #endif
2137 : #define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
2138 : #define S_CASEFOLD (1 << 15) /* Casefolded file */
2139 : #define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
2140 : #define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
2141 :
2142 : /*
2143 : * Note that nosuid etc flags are inode-specific: setting some file-system
2144 : * flags just means all the inodes inherit those flags by default. It might be
2145 : * possible to override it selectively if you really wanted to with some
2146 : * ioctl() that is not currently implemented.
2147 : *
2148 : * Exception: SB_RDONLY is always applied to the entire file system.
2149 : *
2150 : * Unfortunately, it is possible to change a filesystems flags with it mounted
2151 : * with files in use. This means that all of the inodes will not have their
2152 : * i_flags updated. Hence, i_flags no longer inherit the superblock mount
2153 : * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
2154 : */
2155 : #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
2156 :
2157 6 : static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags & SB_RDONLY; }
2158 : #define IS_RDONLY(inode) sb_rdonly((inode)->i_sb)
2159 : #define IS_SYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS) || \
2160 : ((inode)->i_flags & S_SYNC))
2161 : #define IS_DIRSYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
2162 : ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
2163 : #define IS_MANDLOCK(inode) __IS_FLG(inode, SB_MANDLOCK)
2164 : #define IS_NOATIME(inode) __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
2165 : #define IS_I_VERSION(inode) __IS_FLG(inode, SB_I_VERSION)
2166 :
2167 : #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
2168 : #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
2169 : #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
2170 : #define IS_POSIXACL(inode) __IS_FLG(inode, SB_POSIXACL)
2171 :
2172 : #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
2173 : #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
2174 : #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
2175 : #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
2176 : #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
2177 : #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
2178 : #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
2179 : #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
2180 : #define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED)
2181 : #define IS_CASEFOLDED(inode) ((inode)->i_flags & S_CASEFOLD)
2182 : #define IS_VERITY(inode) ((inode)->i_flags & S_VERITY)
2183 :
2184 : #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
2185 : (inode)->i_rdev == WHITEOUT_DEV)
2186 :
2187 3 : static inline bool HAS_UNMAPPED_ID(struct user_namespace *mnt_userns,
2188 : struct inode *inode)
2189 : {
2190 6 : return !uid_valid(i_uid_into_mnt(mnt_userns, inode)) ||
2191 3 : !gid_valid(i_gid_into_mnt(mnt_userns, inode));
2192 : }
2193 :
2194 : static inline int iocb_flags(struct file *file);
2195 :
2196 0 : static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
2197 : {
2198 0 : *kiocb = (struct kiocb) {
2199 : .ki_filp = filp,
2200 0 : .ki_flags = iocb_flags(filp),
2201 0 : .ki_ioprio = get_current_ioprio(),
2202 : };
2203 0 : }
2204 :
2205 : static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
2206 : struct file *filp)
2207 : {
2208 : *kiocb = (struct kiocb) {
2209 : .ki_filp = filp,
2210 : .ki_flags = kiocb_src->ki_flags,
2211 : .ki_ioprio = kiocb_src->ki_ioprio,
2212 : .ki_pos = kiocb_src->ki_pos,
2213 : };
2214 : }
2215 :
2216 : /*
2217 : * Inode state bits. Protected by inode->i_lock
2218 : *
2219 : * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
2220 : * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
2221 : *
2222 : * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
2223 : * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
2224 : * various stages of removing an inode.
2225 : *
2226 : * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
2227 : *
2228 : * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
2229 : * fdatasync() (unless I_DIRTY_DATASYNC is also set).
2230 : * Timestamp updates are the usual cause.
2231 : * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
2232 : * these changes separately from I_DIRTY_SYNC so that we
2233 : * don't have to write inode on fdatasync() when only
2234 : * e.g. the timestamps have changed.
2235 : * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
2236 : * I_DIRTY_TIME The inode itself only has dirty timestamps, and the
2237 : * lazytime mount option is enabled. We keep track of this
2238 : * separately from I_DIRTY_SYNC in order to implement
2239 : * lazytime. This gets cleared if I_DIRTY_INODE
2240 : * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. I.e.
2241 : * either I_DIRTY_TIME *or* I_DIRTY_INODE can be set in
2242 : * i_state, but not both. I_DIRTY_PAGES may still be set.
2243 : * I_NEW Serves as both a mutex and completion notification.
2244 : * New inodes set I_NEW. If two processes both create
2245 : * the same inode, one of them will release its inode and
2246 : * wait for I_NEW to be released before returning.
2247 : * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
2248 : * also cause waiting on I_NEW, without I_NEW actually
2249 : * being set. find_inode() uses this to prevent returning
2250 : * nearly-dead inodes.
2251 : * I_WILL_FREE Must be set when calling write_inode_now() if i_count
2252 : * is zero. I_FREEING must be set when I_WILL_FREE is
2253 : * cleared.
2254 : * I_FREEING Set when inode is about to be freed but still has dirty
2255 : * pages or buffers attached or the inode itself is still
2256 : * dirty.
2257 : * I_CLEAR Added by clear_inode(). In this state the inode is
2258 : * clean and can be destroyed. Inode keeps I_FREEING.
2259 : *
2260 : * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
2261 : * prohibited for many purposes. iget() must wait for
2262 : * the inode to be completely released, then create it
2263 : * anew. Other functions will just ignore such inodes,
2264 : * if appropriate. I_NEW is used for waiting.
2265 : *
2266 : * I_SYNC Writeback of inode is running. The bit is set during
2267 : * data writeback, and cleared with a wakeup on the bit
2268 : * address once it is done. The bit is also used to pin
2269 : * the inode in memory for flusher thread.
2270 : *
2271 : * I_REFERENCED Marks the inode as recently references on the LRU list.
2272 : *
2273 : * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
2274 : *
2275 : * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
2276 : * synchronize competing switching instances and to tell
2277 : * wb stat updates to grab the i_pages lock. See
2278 : * inode_switch_wbs_work_fn() for details.
2279 : *
2280 : * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
2281 : * and work dirs among overlayfs mounts.
2282 : *
2283 : * I_CREATING New object's inode in the middle of setting up.
2284 : *
2285 : * I_DONTCACHE Evict inode as soon as it is not used anymore.
2286 : *
2287 : * I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
2288 : * Used to detect that mark_inode_dirty() should not move
2289 : * inode between dirty lists.
2290 : *
2291 : * I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
2292 : *
2293 : * Q: What is the difference between I_WILL_FREE and I_FREEING?
2294 : */
2295 : #define I_DIRTY_SYNC (1 << 0)
2296 : #define I_DIRTY_DATASYNC (1 << 1)
2297 : #define I_DIRTY_PAGES (1 << 2)
2298 : #define __I_NEW 3
2299 : #define I_NEW (1 << __I_NEW)
2300 : #define I_WILL_FREE (1 << 4)
2301 : #define I_FREEING (1 << 5)
2302 : #define I_CLEAR (1 << 6)
2303 : #define __I_SYNC 7
2304 : #define I_SYNC (1 << __I_SYNC)
2305 : #define I_REFERENCED (1 << 8)
2306 : #define __I_DIO_WAKEUP 9
2307 : #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
2308 : #define I_LINKABLE (1 << 10)
2309 : #define I_DIRTY_TIME (1 << 11)
2310 : #define I_WB_SWITCH (1 << 13)
2311 : #define I_OVL_INUSE (1 << 14)
2312 : #define I_CREATING (1 << 15)
2313 : #define I_DONTCACHE (1 << 16)
2314 : #define I_SYNC_QUEUED (1 << 17)
2315 : #define I_PINNING_FSCACHE_WB (1 << 18)
2316 :
2317 : #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
2318 : #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
2319 : #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
2320 :
2321 : extern void __mark_inode_dirty(struct inode *, int);
2322 : static inline void mark_inode_dirty(struct inode *inode)
2323 : {
2324 0 : __mark_inode_dirty(inode, I_DIRTY);
2325 : }
2326 :
2327 : static inline void mark_inode_dirty_sync(struct inode *inode)
2328 : {
2329 0 : __mark_inode_dirty(inode, I_DIRTY_SYNC);
2330 : }
2331 :
2332 : /*
2333 : * Returns true if the given inode itself only has dirty timestamps (its pages
2334 : * may still be dirty) and isn't currently being allocated or freed.
2335 : * Filesystems should call this if when writing an inode when lazytime is
2336 : * enabled, they want to opportunistically write the timestamps of other inodes
2337 : * located very nearby on-disk, e.g. in the same inode block. This returns true
2338 : * if the given inode is in need of such an opportunistic update. Requires
2339 : * i_lock, or at least later re-checking under i_lock.
2340 : */
2341 : static inline bool inode_is_dirtytime_only(struct inode *inode)
2342 : {
2343 : return (inode->i_state & (I_DIRTY_TIME | I_NEW |
2344 : I_FREEING | I_WILL_FREE)) == I_DIRTY_TIME;
2345 : }
2346 :
2347 : extern void inc_nlink(struct inode *inode);
2348 : extern void drop_nlink(struct inode *inode);
2349 : extern void clear_nlink(struct inode *inode);
2350 : extern void set_nlink(struct inode *inode, unsigned int nlink);
2351 :
2352 : static inline void inode_inc_link_count(struct inode *inode)
2353 : {
2354 : inc_nlink(inode);
2355 : mark_inode_dirty(inode);
2356 : }
2357 :
2358 : static inline void inode_dec_link_count(struct inode *inode)
2359 : {
2360 0 : drop_nlink(inode);
2361 0 : mark_inode_dirty(inode);
2362 : }
2363 :
2364 : enum file_time_flags {
2365 : S_ATIME = 1,
2366 : S_MTIME = 2,
2367 : S_CTIME = 4,
2368 : S_VERSION = 8,
2369 : };
2370 :
2371 : extern bool atime_needs_update(const struct path *, struct inode *);
2372 : extern void touch_atime(const struct path *);
2373 : int inode_update_time(struct inode *inode, struct timespec64 *time, int flags);
2374 :
2375 : static inline void file_accessed(struct file *file)
2376 : {
2377 0 : if (!(file->f_flags & O_NOATIME))
2378 0 : touch_atime(&file->f_path);
2379 : }
2380 :
2381 : extern int file_modified(struct file *file);
2382 :
2383 : int sync_inode_metadata(struct inode *inode, int wait);
2384 :
2385 : struct file_system_type {
2386 : const char *name;
2387 : int fs_flags;
2388 : #define FS_REQUIRES_DEV 1
2389 : #define FS_BINARY_MOUNTDATA 2
2390 : #define FS_HAS_SUBTYPE 4
2391 : #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2392 : #define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
2393 : #define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
2394 : #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2395 : int (*init_fs_context)(struct fs_context *);
2396 : const struct fs_parameter_spec *parameters;
2397 : struct dentry *(*mount) (struct file_system_type *, int,
2398 : const char *, void *);
2399 : void (*kill_sb) (struct super_block *);
2400 : struct module *owner;
2401 : struct file_system_type * next;
2402 : struct hlist_head fs_supers;
2403 :
2404 : struct lock_class_key s_lock_key;
2405 : struct lock_class_key s_umount_key;
2406 : struct lock_class_key s_vfs_rename_key;
2407 : struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
2408 :
2409 : struct lock_class_key i_lock_key;
2410 : struct lock_class_key i_mutex_key;
2411 : struct lock_class_key invalidate_lock_key;
2412 : struct lock_class_key i_mutex_dir_key;
2413 : };
2414 :
2415 : #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2416 :
2417 : extern struct dentry *mount_bdev(struct file_system_type *fs_type,
2418 : int flags, const char *dev_name, void *data,
2419 : int (*fill_super)(struct super_block *, void *, int));
2420 : extern struct dentry *mount_single(struct file_system_type *fs_type,
2421 : int flags, void *data,
2422 : int (*fill_super)(struct super_block *, void *, int));
2423 : extern struct dentry *mount_nodev(struct file_system_type *fs_type,
2424 : int flags, void *data,
2425 : int (*fill_super)(struct super_block *, void *, int));
2426 : extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
2427 : void generic_shutdown_super(struct super_block *sb);
2428 : void kill_block_super(struct super_block *sb);
2429 : void kill_anon_super(struct super_block *sb);
2430 : void kill_litter_super(struct super_block *sb);
2431 : void deactivate_super(struct super_block *sb);
2432 : void deactivate_locked_super(struct super_block *sb);
2433 : int set_anon_super(struct super_block *s, void *data);
2434 : int set_anon_super_fc(struct super_block *s, struct fs_context *fc);
2435 : int get_anon_bdev(dev_t *);
2436 : void free_anon_bdev(dev_t);
2437 : struct super_block *sget_fc(struct fs_context *fc,
2438 : int (*test)(struct super_block *, struct fs_context *),
2439 : int (*set)(struct super_block *, struct fs_context *));
2440 : struct super_block *sget(struct file_system_type *type,
2441 : int (*test)(struct super_block *,void *),
2442 : int (*set)(struct super_block *,void *),
2443 : int flags, void *data);
2444 :
2445 : /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2446 : #define fops_get(fops) \
2447 : (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2448 : #define fops_put(fops) \
2449 : do { if (fops) module_put((fops)->owner); } while(0)
2450 : /*
2451 : * This one is to be used *ONLY* from ->open() instances.
2452 : * fops must be non-NULL, pinned down *and* module dependencies
2453 : * should be sufficient to pin the caller down as well.
2454 : */
2455 : #define replace_fops(f, fops) \
2456 : do { \
2457 : struct file *__file = (f); \
2458 : fops_put(__file->f_op); \
2459 : BUG_ON(!(__file->f_op = (fops))); \
2460 : } while(0)
2461 :
2462 : extern int register_filesystem(struct file_system_type *);
2463 : extern int unregister_filesystem(struct file_system_type *);
2464 : extern struct vfsmount *kern_mount(struct file_system_type *);
2465 : extern void kern_unmount(struct vfsmount *mnt);
2466 : extern int may_umount_tree(struct vfsmount *);
2467 : extern int may_umount(struct vfsmount *);
2468 : extern long do_mount(const char *, const char __user *,
2469 : const char *, unsigned long, void *);
2470 : extern struct vfsmount *collect_mounts(const struct path *);
2471 : extern void drop_collected_mounts(struct vfsmount *);
2472 : extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
2473 : struct vfsmount *);
2474 : extern int vfs_statfs(const struct path *, struct kstatfs *);
2475 : extern int user_statfs(const char __user *, struct kstatfs *);
2476 : extern int fd_statfs(int, struct kstatfs *);
2477 : extern int freeze_super(struct super_block *super);
2478 : extern int thaw_super(struct super_block *super);
2479 : extern bool our_mnt(struct vfsmount *mnt);
2480 : extern __printf(2, 3)
2481 : int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
2482 : extern int super_setup_bdi(struct super_block *sb);
2483 :
2484 : extern int current_umask(void);
2485 :
2486 : extern void ihold(struct inode * inode);
2487 : extern void iput(struct inode *);
2488 : extern int generic_update_time(struct inode *, struct timespec64 *, int);
2489 :
2490 : /* /sys/fs */
2491 : extern struct kobject *fs_kobj;
2492 :
2493 : #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2494 :
2495 : #ifdef CONFIG_FILE_LOCKING
2496 0 : static inline int break_lease(struct inode *inode, unsigned int mode)
2497 : {
2498 : /*
2499 : * Since this check is lockless, we must ensure that any refcounts
2500 : * taken are done before checking i_flctx->flc_lease. Otherwise, we
2501 : * could end up racing with tasks trying to set a new lease on this
2502 : * file.
2503 : */
2504 0 : smp_mb();
2505 0 : if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2506 0 : return __break_lease(inode, mode, FL_LEASE);
2507 : return 0;
2508 : }
2509 :
2510 0 : static inline int break_deleg(struct inode *inode, unsigned int mode)
2511 : {
2512 : /*
2513 : * Since this check is lockless, we must ensure that any refcounts
2514 : * taken are done before checking i_flctx->flc_lease. Otherwise, we
2515 : * could end up racing with tasks trying to set a new lease on this
2516 : * file.
2517 : */
2518 0 : smp_mb();
2519 0 : if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2520 0 : return __break_lease(inode, mode, FL_DELEG);
2521 : return 0;
2522 : }
2523 :
2524 0 : static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2525 : {
2526 : int ret;
2527 :
2528 0 : ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
2529 0 : if (ret == -EWOULDBLOCK && delegated_inode) {
2530 0 : *delegated_inode = inode;
2531 0 : ihold(inode);
2532 : }
2533 0 : return ret;
2534 : }
2535 :
2536 0 : static inline int break_deleg_wait(struct inode **delegated_inode)
2537 : {
2538 : int ret;
2539 :
2540 0 : ret = break_deleg(*delegated_inode, O_WRONLY);
2541 0 : iput(*delegated_inode);
2542 0 : *delegated_inode = NULL;
2543 0 : return ret;
2544 : }
2545 :
2546 : static inline int break_layout(struct inode *inode, bool wait)
2547 : {
2548 : smp_mb();
2549 : if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2550 : return __break_lease(inode,
2551 : wait ? O_WRONLY : O_WRONLY | O_NONBLOCK,
2552 : FL_LAYOUT);
2553 : return 0;
2554 : }
2555 :
2556 : #else /* !CONFIG_FILE_LOCKING */
2557 : static inline int break_lease(struct inode *inode, unsigned int mode)
2558 : {
2559 : return 0;
2560 : }
2561 :
2562 : static inline int break_deleg(struct inode *inode, unsigned int mode)
2563 : {
2564 : return 0;
2565 : }
2566 :
2567 : static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2568 : {
2569 : return 0;
2570 : }
2571 :
2572 : static inline int break_deleg_wait(struct inode **delegated_inode)
2573 : {
2574 : BUG();
2575 : return 0;
2576 : }
2577 :
2578 : static inline int break_layout(struct inode *inode, bool wait)
2579 : {
2580 : return 0;
2581 : }
2582 :
2583 : #endif /* CONFIG_FILE_LOCKING */
2584 :
2585 : /* fs/open.c */
2586 : struct audit_names;
2587 : struct filename {
2588 : const char *name; /* pointer to actual string */
2589 : const __user char *uptr; /* original userland pointer */
2590 : int refcnt;
2591 : struct audit_names *aname;
2592 : const char iname[];
2593 : };
2594 : static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
2595 :
2596 : static inline struct user_namespace *file_mnt_user_ns(struct file *file)
2597 : {
2598 0 : return mnt_user_ns(file->f_path.mnt);
2599 : }
2600 :
2601 : /**
2602 : * is_idmapped_mnt - check whether a mount is mapped
2603 : * @mnt: the mount to check
2604 : *
2605 : * If @mnt has an idmapping attached different from the
2606 : * filesystem's idmapping then @mnt is mapped.
2607 : *
2608 : * Return: true if mount is mapped, false if not.
2609 : */
2610 : static inline bool is_idmapped_mnt(const struct vfsmount *mnt)
2611 : {
2612 0 : return mnt_user_ns(mnt) != mnt->mnt_sb->s_user_ns;
2613 : }
2614 :
2615 : extern long vfs_truncate(const struct path *, loff_t);
2616 : int do_truncate(struct user_namespace *, struct dentry *, loff_t start,
2617 : unsigned int time_attrs, struct file *filp);
2618 : extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2619 : loff_t len);
2620 : extern long do_sys_open(int dfd, const char __user *filename, int flags,
2621 : umode_t mode);
2622 : extern struct file *file_open_name(struct filename *, int, umode_t);
2623 : extern struct file *filp_open(const char *, int, umode_t);
2624 : extern struct file *file_open_root(const struct path *,
2625 : const char *, int, umode_t);
2626 : static inline struct file *file_open_root_mnt(struct vfsmount *mnt,
2627 : const char *name, int flags, umode_t mode)
2628 : {
2629 0 : return file_open_root(&(struct path){.mnt = mnt, .dentry = mnt->mnt_root},
2630 : name, flags, mode);
2631 : }
2632 : extern struct file * dentry_open(const struct path *, int, const struct cred *);
2633 : extern struct file * open_with_fake_path(const struct path *, int,
2634 : struct inode*, const struct cred *);
2635 : static inline struct file *file_clone_open(struct file *file)
2636 : {
2637 0 : return dentry_open(&file->f_path, file->f_flags, file->f_cred);
2638 : }
2639 : extern int filp_close(struct file *, fl_owner_t id);
2640 :
2641 : extern struct filename *getname_flags(const char __user *, int, int *);
2642 : extern struct filename *getname_uflags(const char __user *, int);
2643 : extern struct filename *getname(const char __user *);
2644 : extern struct filename *getname_kernel(const char *);
2645 : extern void putname(struct filename *name);
2646 :
2647 : extern int finish_open(struct file *file, struct dentry *dentry,
2648 : int (*open)(struct inode *, struct file *));
2649 : extern int finish_no_open(struct file *file, struct dentry *dentry);
2650 :
2651 : /* fs/dcache.c */
2652 : extern void __init vfs_caches_init_early(void);
2653 : extern void __init vfs_caches_init(void);
2654 :
2655 : extern struct kmem_cache *names_cachep;
2656 :
2657 : #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2658 : #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2659 :
2660 : extern struct super_block *blockdev_superblock;
2661 : static inline bool sb_is_blkdev_sb(struct super_block *sb)
2662 : {
2663 0 : return IS_ENABLED(CONFIG_BLOCK) && sb == blockdev_superblock;
2664 : }
2665 :
2666 : void emergency_thaw_all(void);
2667 : extern int sync_filesystem(struct super_block *);
2668 : extern const struct file_operations def_blk_fops;
2669 : extern const struct file_operations def_chr_fops;
2670 :
2671 : /* fs/char_dev.c */
2672 : #define CHRDEV_MAJOR_MAX 512
2673 : /* Marks the bottom of the first segment of free char majors */
2674 : #define CHRDEV_MAJOR_DYN_END 234
2675 : /* Marks the top and bottom of the second segment of free char majors */
2676 : #define CHRDEV_MAJOR_DYN_EXT_START 511
2677 : #define CHRDEV_MAJOR_DYN_EXT_END 384
2678 :
2679 : extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2680 : extern int register_chrdev_region(dev_t, unsigned, const char *);
2681 : extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2682 : unsigned int count, const char *name,
2683 : const struct file_operations *fops);
2684 : extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2685 : unsigned int count, const char *name);
2686 : extern void unregister_chrdev_region(dev_t, unsigned);
2687 : extern void chrdev_show(struct seq_file *,off_t);
2688 :
2689 : static inline int register_chrdev(unsigned int major, const char *name,
2690 : const struct file_operations *fops)
2691 : {
2692 3 : return __register_chrdev(major, 0, 256, name, fops);
2693 : }
2694 :
2695 : static inline void unregister_chrdev(unsigned int major, const char *name)
2696 : {
2697 0 : __unregister_chrdev(major, 0, 256, name);
2698 : }
2699 :
2700 : extern void init_special_inode(struct inode *, umode_t, dev_t);
2701 :
2702 : /* Invalid inode operations -- fs/bad_inode.c */
2703 : extern void make_bad_inode(struct inode *);
2704 : extern bool is_bad_inode(struct inode *);
2705 :
2706 : extern int __must_check file_fdatawait_range(struct file *file, loff_t lstart,
2707 : loff_t lend);
2708 : extern int __must_check file_check_and_advance_wb_err(struct file *file);
2709 : extern int __must_check file_write_and_wait_range(struct file *file,
2710 : loff_t start, loff_t end);
2711 :
2712 : static inline int file_write_and_wait(struct file *file)
2713 : {
2714 : return file_write_and_wait_range(file, 0, LLONG_MAX);
2715 : }
2716 :
2717 : extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2718 : int datasync);
2719 : extern int vfs_fsync(struct file *file, int datasync);
2720 :
2721 : extern int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
2722 : unsigned int flags);
2723 :
2724 : /*
2725 : * Sync the bytes written if this was a synchronous write. Expect ki_pos
2726 : * to already be updated for the write, and will return either the amount
2727 : * of bytes passed in, or an error if syncing the file failed.
2728 : */
2729 0 : static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
2730 : {
2731 0 : if (iocb->ki_flags & IOCB_DSYNC) {
2732 0 : int ret = vfs_fsync_range(iocb->ki_filp,
2733 0 : iocb->ki_pos - count, iocb->ki_pos - 1,
2734 0 : (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
2735 0 : if (ret)
2736 0 : return ret;
2737 : }
2738 :
2739 : return count;
2740 : }
2741 :
2742 : extern void emergency_sync(void);
2743 : extern void emergency_remount(void);
2744 :
2745 : #ifdef CONFIG_BLOCK
2746 : extern int bmap(struct inode *inode, sector_t *block);
2747 : #else
2748 : static inline int bmap(struct inode *inode, sector_t *block)
2749 : {
2750 : return -EINVAL;
2751 : }
2752 : #endif
2753 :
2754 : int notify_change(struct user_namespace *, struct dentry *,
2755 : struct iattr *, struct inode **);
2756 : int inode_permission(struct user_namespace *, struct inode *, int);
2757 : int generic_permission(struct user_namespace *, struct inode *, int);
2758 : static inline int file_permission(struct file *file, int mask)
2759 : {
2760 0 : return inode_permission(file_mnt_user_ns(file),
2761 : file_inode(file), mask);
2762 : }
2763 : static inline int path_permission(const struct path *path, int mask)
2764 : {
2765 0 : return inode_permission(mnt_user_ns(path->mnt),
2766 0 : d_inode(path->dentry), mask);
2767 : }
2768 : int __check_sticky(struct user_namespace *mnt_userns, struct inode *dir,
2769 : struct inode *inode);
2770 :
2771 : static inline bool execute_ok(struct inode *inode)
2772 : {
2773 : return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2774 : }
2775 :
2776 : static inline bool inode_wrong_type(const struct inode *inode, umode_t mode)
2777 : {
2778 : return (inode->i_mode ^ mode) & S_IFMT;
2779 : }
2780 :
2781 : static inline void file_start_write(struct file *file)
2782 : {
2783 0 : if (!S_ISREG(file_inode(file)->i_mode))
2784 : return;
2785 0 : sb_start_write(file_inode(file)->i_sb);
2786 : }
2787 :
2788 : static inline bool file_start_write_trylock(struct file *file)
2789 : {
2790 : if (!S_ISREG(file_inode(file)->i_mode))
2791 : return true;
2792 : return sb_start_write_trylock(file_inode(file)->i_sb);
2793 : }
2794 :
2795 : static inline void file_end_write(struct file *file)
2796 : {
2797 0 : if (!S_ISREG(file_inode(file)->i_mode))
2798 : return;
2799 0 : __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2800 : }
2801 :
2802 : /*
2803 : * This is used for regular files where some users -- especially the
2804 : * currently executed binary in a process, previously handled via
2805 : * VM_DENYWRITE -- cannot handle concurrent write (and maybe mmap
2806 : * read-write shared) accesses.
2807 : *
2808 : * get_write_access() gets write permission for a file.
2809 : * put_write_access() releases this write permission.
2810 : * deny_write_access() denies write access to a file.
2811 : * allow_write_access() re-enables write access to a file.
2812 : *
2813 : * The i_writecount field of an inode can have the following values:
2814 : * 0: no write access, no denied write access
2815 : * < 0: (-i_writecount) users that denied write access to the file.
2816 : * > 0: (i_writecount) users that have write access to the file.
2817 : *
2818 : * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2819 : * except for the cases where we don't hold i_writecount yet. Then we need to
2820 : * use {get,deny}_write_access() - these functions check the sign and refuse
2821 : * to do the change if sign is wrong.
2822 : */
2823 : static inline int get_write_access(struct inode *inode)
2824 : {
2825 0 : return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2826 : }
2827 : static inline int deny_write_access(struct file *file)
2828 : {
2829 0 : struct inode *inode = file_inode(file);
2830 0 : return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2831 : }
2832 : static inline void put_write_access(struct inode * inode)
2833 : {
2834 0 : atomic_dec(&inode->i_writecount);
2835 : }
2836 : static inline void allow_write_access(struct file *file)
2837 : {
2838 0 : if (file)
2839 0 : atomic_inc(&file_inode(file)->i_writecount);
2840 : }
2841 : static inline bool inode_is_open_for_write(const struct inode *inode)
2842 : {
2843 0 : return atomic_read(&inode->i_writecount) > 0;
2844 : }
2845 :
2846 : #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
2847 0 : static inline void i_readcount_dec(struct inode *inode)
2848 : {
2849 0 : BUG_ON(!atomic_read(&inode->i_readcount));
2850 0 : atomic_dec(&inode->i_readcount);
2851 0 : }
2852 : static inline void i_readcount_inc(struct inode *inode)
2853 : {
2854 0 : atomic_inc(&inode->i_readcount);
2855 : }
2856 : #else
2857 : static inline void i_readcount_dec(struct inode *inode)
2858 : {
2859 : return;
2860 : }
2861 : static inline void i_readcount_inc(struct inode *inode)
2862 : {
2863 : return;
2864 : }
2865 : #endif
2866 : extern int do_pipe_flags(int *, int);
2867 :
2868 : extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
2869 : ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos);
2870 : extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *);
2871 : extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *);
2872 : extern struct file * open_exec(const char *);
2873 :
2874 : /* fs/dcache.c -- generic fs support functions */
2875 : extern bool is_subdir(struct dentry *, struct dentry *);
2876 : extern bool path_is_under(const struct path *, const struct path *);
2877 :
2878 : extern char *file_path(struct file *, char *, int);
2879 :
2880 : #include <linux/err.h>
2881 :
2882 : /* needed for stackable file system support */
2883 : extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2884 :
2885 : extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2886 :
2887 : extern int inode_init_always(struct super_block *, struct inode *);
2888 : extern void inode_init_once(struct inode *);
2889 : extern void address_space_init_once(struct address_space *mapping);
2890 : extern struct inode * igrab(struct inode *);
2891 : extern ino_t iunique(struct super_block *, ino_t);
2892 : extern int inode_needs_sync(struct inode *inode);
2893 : extern int generic_delete_inode(struct inode *inode);
2894 : static inline int generic_drop_inode(struct inode *inode)
2895 : {
2896 0 : return !inode->i_nlink || inode_unhashed(inode);
2897 : }
2898 : extern void d_mark_dontcache(struct inode *inode);
2899 :
2900 : extern struct inode *ilookup5_nowait(struct super_block *sb,
2901 : unsigned long hashval, int (*test)(struct inode *, void *),
2902 : void *data);
2903 : extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2904 : int (*test)(struct inode *, void *), void *data);
2905 : extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2906 :
2907 : extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
2908 : int (*test)(struct inode *, void *),
2909 : int (*set)(struct inode *, void *),
2910 : void *data);
2911 : extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2912 : extern struct inode * iget_locked(struct super_block *, unsigned long);
2913 : extern struct inode *find_inode_nowait(struct super_block *,
2914 : unsigned long,
2915 : int (*match)(struct inode *,
2916 : unsigned long, void *),
2917 : void *data);
2918 : extern struct inode *find_inode_rcu(struct super_block *, unsigned long,
2919 : int (*)(struct inode *, void *), void *);
2920 : extern struct inode *find_inode_by_ino_rcu(struct super_block *, unsigned long);
2921 : extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2922 : extern int insert_inode_locked(struct inode *);
2923 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
2924 : extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2925 : #else
2926 : static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2927 : #endif
2928 : extern void unlock_new_inode(struct inode *);
2929 : extern void discard_new_inode(struct inode *);
2930 : extern unsigned int get_next_ino(void);
2931 : extern void evict_inodes(struct super_block *sb);
2932 : void dump_mapping(const struct address_space *);
2933 :
2934 : /*
2935 : * Userspace may rely on the the inode number being non-zero. For example, glibc
2936 : * simply ignores files with zero i_ino in unlink() and other places.
2937 : *
2938 : * As an additional complication, if userspace was compiled with
2939 : * _FILE_OFFSET_BITS=32 on a 64-bit kernel we'll only end up reading out the
2940 : * lower 32 bits, so we need to check that those aren't zero explicitly. With
2941 : * _FILE_OFFSET_BITS=64, this may cause some harmless false-negatives, but
2942 : * better safe than sorry.
2943 : */
2944 : static inline bool is_zero_ino(ino_t ino)
2945 : {
2946 1 : return (u32)ino == 0;
2947 : }
2948 :
2949 : extern void __iget(struct inode * inode);
2950 : extern void iget_failed(struct inode *);
2951 : extern void clear_inode(struct inode *);
2952 : extern void __destroy_inode(struct inode *);
2953 : extern struct inode *new_inode_pseudo(struct super_block *sb);
2954 : extern struct inode *new_inode(struct super_block *sb);
2955 : extern void free_inode_nonrcu(struct inode *inode);
2956 : extern int should_remove_suid(struct dentry *);
2957 : extern int file_remove_privs(struct file *);
2958 :
2959 : /*
2960 : * This must be used for allocating filesystems specific inodes to set
2961 : * up the inode reclaim context correctly.
2962 : */
2963 : static inline void *
2964 : alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp)
2965 : {
2966 17 : return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp);
2967 : }
2968 :
2969 : extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2970 : static inline void insert_inode_hash(struct inode *inode)
2971 : {
2972 0 : __insert_inode_hash(inode, inode->i_ino);
2973 : }
2974 :
2975 : extern void __remove_inode_hash(struct inode *);
2976 : static inline void remove_inode_hash(struct inode *inode)
2977 : {
2978 0 : if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
2979 0 : __remove_inode_hash(inode);
2980 : }
2981 :
2982 : extern void inode_sb_list_add(struct inode *inode);
2983 : extern void inode_add_lru(struct inode *inode);
2984 :
2985 : extern int sb_set_blocksize(struct super_block *, int);
2986 : extern int sb_min_blocksize(struct super_block *, int);
2987 :
2988 : extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2989 : extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2990 : extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
2991 : int generic_write_checks_count(struct kiocb *iocb, loff_t *count);
2992 : extern int generic_write_check_limits(struct file *file, loff_t pos,
2993 : loff_t *count);
2994 : extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);
2995 : ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *to,
2996 : ssize_t already_read);
2997 : extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2998 : extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
2999 : extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
3000 : extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
3001 : ssize_t generic_perform_write(struct kiocb *, struct iov_iter *);
3002 :
3003 : ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
3004 : rwf_t flags);
3005 : ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
3006 : rwf_t flags);
3007 : ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb,
3008 : struct iov_iter *iter);
3009 : ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb,
3010 : struct iov_iter *iter);
3011 :
3012 : /* fs/splice.c */
3013 : extern ssize_t generic_file_splice_read(struct file *, loff_t *,
3014 : struct pipe_inode_info *, size_t, unsigned int);
3015 : extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
3016 : struct file *, loff_t *, size_t, unsigned int);
3017 : extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
3018 : struct file *out, loff_t *, size_t len, unsigned int flags);
3019 : extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
3020 : loff_t *opos, size_t len, unsigned int flags);
3021 :
3022 :
3023 : extern void
3024 : file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
3025 : extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
3026 : extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
3027 : extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
3028 : extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
3029 : extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
3030 : int whence, loff_t maxsize, loff_t eof);
3031 : extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
3032 : int whence, loff_t size);
3033 : extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
3034 : extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
3035 : int rw_verify_area(int, struct file *, const loff_t *, size_t);
3036 : extern int generic_file_open(struct inode * inode, struct file * filp);
3037 : extern int nonseekable_open(struct inode * inode, struct file * filp);
3038 : extern int stream_open(struct inode * inode, struct file * filp);
3039 :
3040 : #ifdef CONFIG_BLOCK
3041 : typedef void (dio_submit_t)(struct bio *bio, struct inode *inode,
3042 : loff_t file_offset);
3043 :
3044 : enum {
3045 : /* need locking between buffered and direct access */
3046 : DIO_LOCKING = 0x01,
3047 :
3048 : /* filesystem does not support filling holes */
3049 : DIO_SKIP_HOLES = 0x02,
3050 : };
3051 :
3052 : ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
3053 : struct block_device *bdev, struct iov_iter *iter,
3054 : get_block_t get_block,
3055 : dio_iodone_t end_io, dio_submit_t submit_io,
3056 : int flags);
3057 :
3058 : static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
3059 : struct inode *inode,
3060 : struct iov_iter *iter,
3061 : get_block_t get_block)
3062 : {
3063 : return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
3064 : get_block, NULL, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
3065 : }
3066 : #endif
3067 :
3068 : void inode_dio_wait(struct inode *inode);
3069 :
3070 : /**
3071 : * inode_dio_begin - signal start of a direct I/O requests
3072 : * @inode: inode the direct I/O happens on
3073 : *
3074 : * This is called once we've finished processing a direct I/O request,
3075 : * and is used to wake up callers waiting for direct I/O to be quiesced.
3076 : */
3077 : static inline void inode_dio_begin(struct inode *inode)
3078 : {
3079 0 : atomic_inc(&inode->i_dio_count);
3080 : }
3081 :
3082 : /**
3083 : * inode_dio_end - signal finish of a direct I/O requests
3084 : * @inode: inode the direct I/O happens on
3085 : *
3086 : * This is called once we've finished processing a direct I/O request,
3087 : * and is used to wake up callers waiting for direct I/O to be quiesced.
3088 : */
3089 : static inline void inode_dio_end(struct inode *inode)
3090 : {
3091 0 : if (atomic_dec_and_test(&inode->i_dio_count))
3092 0 : wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
3093 : }
3094 :
3095 : /*
3096 : * Warn about a page cache invalidation failure diring a direct I/O write.
3097 : */
3098 : void dio_warn_stale_pagecache(struct file *filp);
3099 :
3100 : extern void inode_set_flags(struct inode *inode, unsigned int flags,
3101 : unsigned int mask);
3102 :
3103 : extern const struct file_operations generic_ro_fops;
3104 :
3105 : #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
3106 :
3107 : extern int readlink_copy(char __user *, int, const char *);
3108 : extern int page_readlink(struct dentry *, char __user *, int);
3109 : extern const char *page_get_link(struct dentry *, struct inode *,
3110 : struct delayed_call *);
3111 : extern void page_put_link(void *);
3112 : extern int __page_symlink(struct inode *inode, const char *symname, int len,
3113 : int nofs);
3114 : extern int page_symlink(struct inode *inode, const char *symname, int len);
3115 : extern const struct inode_operations page_symlink_inode_operations;
3116 : extern void kfree_link(void *);
3117 : void generic_fillattr(struct user_namespace *, struct inode *, struct kstat *);
3118 : void generic_fill_statx_attr(struct inode *inode, struct kstat *stat);
3119 : extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
3120 : extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
3121 : void __inode_add_bytes(struct inode *inode, loff_t bytes);
3122 : void inode_add_bytes(struct inode *inode, loff_t bytes);
3123 : void __inode_sub_bytes(struct inode *inode, loff_t bytes);
3124 : void inode_sub_bytes(struct inode *inode, loff_t bytes);
3125 : static inline loff_t __inode_get_bytes(struct inode *inode)
3126 : {
3127 0 : return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
3128 : }
3129 : loff_t inode_get_bytes(struct inode *inode);
3130 : void inode_set_bytes(struct inode *inode, loff_t bytes);
3131 : const char *simple_get_link(struct dentry *, struct inode *,
3132 : struct delayed_call *);
3133 : extern const struct inode_operations simple_symlink_inode_operations;
3134 :
3135 : extern int iterate_dir(struct file *, struct dir_context *);
3136 :
3137 : int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
3138 : int flags);
3139 : int vfs_fstat(int fd, struct kstat *stat);
3140 :
3141 : static inline int vfs_stat(const char __user *filename, struct kstat *stat)
3142 : {
3143 0 : return vfs_fstatat(AT_FDCWD, filename, stat, 0);
3144 : }
3145 : static inline int vfs_lstat(const char __user *name, struct kstat *stat)
3146 : {
3147 0 : return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
3148 : }
3149 :
3150 : extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
3151 : extern int vfs_readlink(struct dentry *, char __user *, int);
3152 :
3153 : extern struct file_system_type *get_filesystem(struct file_system_type *fs);
3154 : extern void put_filesystem(struct file_system_type *fs);
3155 : extern struct file_system_type *get_fs_type(const char *name);
3156 : extern struct super_block *get_super(struct block_device *);
3157 : extern struct super_block *get_active_super(struct block_device *bdev);
3158 : extern void drop_super(struct super_block *sb);
3159 : extern void drop_super_exclusive(struct super_block *sb);
3160 : extern void iterate_supers(void (*)(struct super_block *, void *), void *);
3161 : extern void iterate_supers_type(struct file_system_type *,
3162 : void (*)(struct super_block *, void *), void *);
3163 :
3164 : extern int dcache_dir_open(struct inode *, struct file *);
3165 : extern int dcache_dir_close(struct inode *, struct file *);
3166 : extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
3167 : extern int dcache_readdir(struct file *, struct dir_context *);
3168 : extern int simple_setattr(struct user_namespace *, struct dentry *,
3169 : struct iattr *);
3170 : extern int simple_getattr(struct user_namespace *, const struct path *,
3171 : struct kstat *, u32, unsigned int);
3172 : extern int simple_statfs(struct dentry *, struct kstatfs *);
3173 : extern int simple_open(struct inode *inode, struct file *file);
3174 : extern int simple_link(struct dentry *, struct inode *, struct dentry *);
3175 : extern int simple_unlink(struct inode *, struct dentry *);
3176 : extern int simple_rmdir(struct inode *, struct dentry *);
3177 : extern int simple_rename_exchange(struct inode *old_dir, struct dentry *old_dentry,
3178 : struct inode *new_dir, struct dentry *new_dentry);
3179 : extern int simple_rename(struct user_namespace *, struct inode *,
3180 : struct dentry *, struct inode *, struct dentry *,
3181 : unsigned int);
3182 : extern void simple_recursive_removal(struct dentry *,
3183 : void (*callback)(struct dentry *));
3184 : extern int noop_fsync(struct file *, loff_t, loff_t, int);
3185 : extern ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
3186 : extern int simple_empty(struct dentry *);
3187 : extern int simple_write_begin(struct file *file, struct address_space *mapping,
3188 : loff_t pos, unsigned len, unsigned flags,
3189 : struct page **pagep, void **fsdata);
3190 : extern const struct address_space_operations ram_aops;
3191 : extern int always_delete_dentry(const struct dentry *);
3192 : extern struct inode *alloc_anon_inode(struct super_block *);
3193 : extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
3194 : extern const struct dentry_operations simple_dentry_operations;
3195 :
3196 : extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
3197 : extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
3198 : extern const struct file_operations simple_dir_operations;
3199 : extern const struct inode_operations simple_dir_inode_operations;
3200 : extern void make_empty_dir_inode(struct inode *inode);
3201 : extern bool is_empty_dir_inode(struct inode *inode);
3202 : struct tree_descr { const char *name; const struct file_operations *ops; int mode; };
3203 : struct dentry *d_alloc_name(struct dentry *, const char *);
3204 : extern int simple_fill_super(struct super_block *, unsigned long,
3205 : const struct tree_descr *);
3206 : extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
3207 : extern void simple_release_fs(struct vfsmount **mount, int *count);
3208 :
3209 : extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
3210 : loff_t *ppos, const void *from, size_t available);
3211 : extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
3212 : const void __user *from, size_t count);
3213 :
3214 : extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
3215 : extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
3216 :
3217 : extern int generic_check_addressable(unsigned, u64);
3218 :
3219 : extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
3220 :
3221 : #ifdef CONFIG_MIGRATION
3222 : extern int buffer_migrate_page(struct address_space *,
3223 : struct page *, struct page *,
3224 : enum migrate_mode);
3225 : extern int buffer_migrate_page_norefs(struct address_space *,
3226 : struct page *, struct page *,
3227 : enum migrate_mode);
3228 : #else
3229 : #define buffer_migrate_page NULL
3230 : #define buffer_migrate_page_norefs NULL
3231 : #endif
3232 :
3233 : int may_setattr(struct user_namespace *mnt_userns, struct inode *inode,
3234 : unsigned int ia_valid);
3235 : int setattr_prepare(struct user_namespace *, struct dentry *, struct iattr *);
3236 : extern int inode_newsize_ok(const struct inode *, loff_t offset);
3237 : void setattr_copy(struct user_namespace *, struct inode *inode,
3238 : const struct iattr *attr);
3239 :
3240 : extern int file_update_time(struct file *file);
3241 :
3242 : static inline bool vma_is_dax(const struct vm_area_struct *vma)
3243 : {
3244 : return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
3245 : }
3246 :
3247 : static inline bool vma_is_fsdax(struct vm_area_struct *vma)
3248 : {
3249 : struct inode *inode;
3250 :
3251 : if (!IS_ENABLED(CONFIG_FS_DAX) || !vma->vm_file)
3252 : return false;
3253 : if (!vma_is_dax(vma))
3254 : return false;
3255 : inode = file_inode(vma->vm_file);
3256 : if (S_ISCHR(inode->i_mode))
3257 : return false; /* device-dax */
3258 : return true;
3259 : }
3260 :
3261 0 : static inline int iocb_flags(struct file *file)
3262 : {
3263 0 : int res = 0;
3264 0 : if (file->f_flags & O_APPEND)
3265 0 : res |= IOCB_APPEND;
3266 0 : if (file->f_flags & O_DIRECT)
3267 0 : res |= IOCB_DIRECT;
3268 0 : if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
3269 0 : res |= IOCB_DSYNC;
3270 0 : if (file->f_flags & __O_SYNC)
3271 0 : res |= IOCB_SYNC;
3272 0 : return res;
3273 : }
3274 :
3275 0 : static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
3276 : {
3277 0 : int kiocb_flags = 0;
3278 :
3279 : /* make sure there's no overlap between RWF and private IOCB flags */
3280 : BUILD_BUG_ON((__force int) RWF_SUPPORTED & IOCB_EVENTFD);
3281 :
3282 0 : if (!flags)
3283 : return 0;
3284 0 : if (unlikely(flags & ~RWF_SUPPORTED))
3285 : return -EOPNOTSUPP;
3286 :
3287 0 : if (flags & RWF_NOWAIT) {
3288 0 : if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
3289 : return -EOPNOTSUPP;
3290 : kiocb_flags |= IOCB_NOIO;
3291 : }
3292 0 : kiocb_flags |= (__force int) (flags & RWF_SUPPORTED);
3293 0 : if (flags & RWF_SYNC)
3294 0 : kiocb_flags |= IOCB_DSYNC;
3295 :
3296 0 : ki->ki_flags |= kiocb_flags;
3297 : return 0;
3298 : }
3299 :
3300 : static inline ino_t parent_ino(struct dentry *dentry)
3301 : {
3302 : ino_t res;
3303 :
3304 : /*
3305 : * Don't strictly need d_lock here? If the parent ino could change
3306 : * then surely we'd have a deeper race in the caller?
3307 : */
3308 0 : spin_lock(&dentry->d_lock);
3309 0 : res = dentry->d_parent->d_inode->i_ino;
3310 0 : spin_unlock(&dentry->d_lock);
3311 : return res;
3312 : }
3313 :
3314 : /* Transaction based IO helpers */
3315 :
3316 : /*
3317 : * An argresp is stored in an allocated page and holds the
3318 : * size of the argument or response, along with its content
3319 : */
3320 : struct simple_transaction_argresp {
3321 : ssize_t size;
3322 : char data[];
3323 : };
3324 :
3325 : #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3326 :
3327 : char *simple_transaction_get(struct file *file, const char __user *buf,
3328 : size_t size);
3329 : ssize_t simple_transaction_read(struct file *file, char __user *buf,
3330 : size_t size, loff_t *pos);
3331 : int simple_transaction_release(struct inode *inode, struct file *file);
3332 :
3333 : void simple_transaction_set(struct file *file, size_t n);
3334 :
3335 : /*
3336 : * simple attribute files
3337 : *
3338 : * These attributes behave similar to those in sysfs:
3339 : *
3340 : * Writing to an attribute immediately sets a value, an open file can be
3341 : * written to multiple times.
3342 : *
3343 : * Reading from an attribute creates a buffer from the value that might get
3344 : * read with multiple read calls. When the attribute has been read
3345 : * completely, no further read calls are possible until the file is opened
3346 : * again.
3347 : *
3348 : * All attributes contain a text representation of a numeric value
3349 : * that are accessed with the get() and set() functions.
3350 : */
3351 : #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3352 : static int __fops ## _open(struct inode *inode, struct file *file) \
3353 : { \
3354 : __simple_attr_check_format(__fmt, 0ull); \
3355 : return simple_attr_open(inode, file, __get, __set, __fmt); \
3356 : } \
3357 : static const struct file_operations __fops = { \
3358 : .owner = THIS_MODULE, \
3359 : .open = __fops ## _open, \
3360 : .release = simple_attr_release, \
3361 : .read = simple_attr_read, \
3362 : .write = simple_attr_write, \
3363 : .llseek = generic_file_llseek, \
3364 : }
3365 :
3366 : static inline __printf(1, 2)
3367 : void __simple_attr_check_format(const char *fmt, ...)
3368 : {
3369 : /* don't do anything, just let the compiler check the arguments; */
3370 : }
3371 :
3372 : int simple_attr_open(struct inode *inode, struct file *file,
3373 : int (*get)(void *, u64 *), int (*set)(void *, u64),
3374 : const char *fmt);
3375 : int simple_attr_release(struct inode *inode, struct file *file);
3376 : ssize_t simple_attr_read(struct file *file, char __user *buf,
3377 : size_t len, loff_t *ppos);
3378 : ssize_t simple_attr_write(struct file *file, const char __user *buf,
3379 : size_t len, loff_t *ppos);
3380 :
3381 : struct ctl_table;
3382 : int __init list_bdev_fs_names(char *buf, size_t size);
3383 :
3384 : #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3385 : #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3386 :
3387 : #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3388 : #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3389 : (flag & __FMODE_NONOTIFY)))
3390 :
3391 : static inline bool is_sxid(umode_t mode)
3392 : {
3393 0 : return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
3394 : }
3395 :
3396 : static inline int check_sticky(struct user_namespace *mnt_userns,
3397 : struct inode *dir, struct inode *inode)
3398 : {
3399 0 : if (!(dir->i_mode & S_ISVTX))
3400 : return 0;
3401 :
3402 0 : return __check_sticky(mnt_userns, dir, inode);
3403 : }
3404 :
3405 : static inline void inode_has_no_xattr(struct inode *inode)
3406 : {
3407 0 : if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & SB_NOSEC))
3408 0 : inode->i_flags |= S_NOSEC;
3409 : }
3410 :
3411 : static inline bool is_root_inode(struct inode *inode)
3412 : {
3413 : return inode == inode->i_sb->s_root->d_inode;
3414 : }
3415 :
3416 : static inline bool dir_emit(struct dir_context *ctx,
3417 : const char *name, int namelen,
3418 : u64 ino, unsigned type)
3419 : {
3420 0 : return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
3421 : }
3422 : static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
3423 : {
3424 0 : return ctx->actor(ctx, ".", 1, ctx->pos,
3425 0 : file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
3426 : }
3427 : static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
3428 : {
3429 0 : return ctx->actor(ctx, "..", 2, ctx->pos,
3430 0 : parent_ino(file->f_path.dentry), DT_DIR) == 0;
3431 : }
3432 0 : static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
3433 : {
3434 0 : if (ctx->pos == 0) {
3435 0 : if (!dir_emit_dot(file, ctx))
3436 : return false;
3437 0 : ctx->pos = 1;
3438 : }
3439 0 : if (ctx->pos == 1) {
3440 0 : if (!dir_emit_dotdot(file, ctx))
3441 : return false;
3442 0 : ctx->pos = 2;
3443 : }
3444 : return true;
3445 : }
3446 : static inline bool dir_relax(struct inode *inode)
3447 : {
3448 : inode_unlock(inode);
3449 : inode_lock(inode);
3450 : return !IS_DEADDIR(inode);
3451 : }
3452 :
3453 : static inline bool dir_relax_shared(struct inode *inode)
3454 : {
3455 : inode_unlock_shared(inode);
3456 : inode_lock_shared(inode);
3457 : return !IS_DEADDIR(inode);
3458 : }
3459 :
3460 : extern bool path_noexec(const struct path *path);
3461 : extern void inode_nohighmem(struct inode *inode);
3462 :
3463 : /* mm/fadvise.c */
3464 : extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len,
3465 : int advice);
3466 : extern int generic_fadvise(struct file *file, loff_t offset, loff_t len,
3467 : int advice);
3468 :
3469 : #endif /* _LINUX_FS_H */
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