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