1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/linkage.h>
6 #include <linux/wait_bit.h>
7 #include <linux/kdev_t.h>
8 #include <linux/dcache.h>
9 #include <linux/path.h>
10 #include <linux/stat.h>
11 #include <linux/cache.h>
12 #include <linux/list.h>
13 #include <linux/list_lru.h>
14 #include <linux/llist.h>
15 #include <linux/radix-tree.h>
16 #include <linux/xarray.h>
17 #include <linux/rbtree.h>
18 #include <linux/init.h>
19 #include <linux/pid.h>
20 #include <linux/bug.h>
21 #include <linux/mutex.h>
22 #include <linux/rwsem.h>
23 #include <linux/mm_types.h>
24 #include <linux/capability.h>
25 #include <linux/semaphore.h>
26 #include <linux/fcntl.h>
27 #include <linux/rculist_bl.h>
28 #include <linux/atomic.h>
29 #include <linux/shrinker.h>
30 #include <linux/migrate_mode.h>
31 #include <linux/uidgid.h>
32 #include <linux/lockdep.h>
33 #include <linux/percpu-rwsem.h>
34 #include <linux/workqueue.h>
35 #include <linux/delayed_call.h>
36 #include <linux/uuid.h>
37 #include <linux/errseq.h>
38 #include <linux/ioprio.h>
39 #include <linux/fs_types.h>
40 #include <linux/build_bug.h>
41 #include <linux/stddef.h>
42 #include <linux/mount.h>
43 #include <linux/cred.h>
44 #include <linux/mnt_idmapping.h>
45 #include <linux/slab.h>
47 #include <asm/byteorder.h>
48 #include <uapi/linux/fs.h>
50 struct backing_dev_info;
54 struct export_operations;
55 struct fiemap_extent_info;
60 struct pipe_inode_info;
61 struct poll_table_struct;
63 struct vm_area_struct;
66 struct swap_info_struct;
68 struct workqueue_struct;
70 struct fscrypt_inode_info;
71 struct fscrypt_operations;
73 struct fsverity_operations;
75 struct fs_parameter_spec;
79 extern void __init inode_init(void);
80 extern void __init inode_init_early(void);
81 extern void __init files_init(void);
82 extern void __init files_maxfiles_init(void);
84 extern unsigned long get_max_files(void);
85 extern unsigned int sysctl_nr_open;
87 typedef __kernel_rwf_t rwf_t;
90 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
91 struct buffer_head *bh_result, int create);
92 typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
93 ssize_t bytes, void *private);
95 #define MAY_EXEC 0x00000001
96 #define MAY_WRITE 0x00000002
97 #define MAY_READ 0x00000004
98 #define MAY_APPEND 0x00000008
99 #define MAY_ACCESS 0x00000010
100 #define MAY_OPEN 0x00000020
101 #define MAY_CHDIR 0x00000040
102 /* called from RCU mode, don't block */
103 #define MAY_NOT_BLOCK 0x00000080
106 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
107 * to O_WRONLY and O_RDWR via the strange trick in do_dentry_open()
110 /* file is open for reading */
111 #define FMODE_READ ((__force fmode_t)0x1)
112 /* file is open for writing */
113 #define FMODE_WRITE ((__force fmode_t)0x2)
114 /* file is seekable */
115 #define FMODE_LSEEK ((__force fmode_t)0x4)
116 /* file can be accessed using pread */
117 #define FMODE_PREAD ((__force fmode_t)0x8)
118 /* file can be accessed using pwrite */
119 #define FMODE_PWRITE ((__force fmode_t)0x10)
120 /* File is opened for execution with sys_execve / sys_uselib */
121 #define FMODE_EXEC ((__force fmode_t)0x20)
122 /* 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)
128 * Don't update ctime and mtime.
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.
133 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
135 /* Expect random access pattern */
136 #define FMODE_RANDOM ((__force fmode_t)0x1000)
138 /* File is huge (eg. /dev/mem): treat loff_t as unsigned */
139 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
141 /* File is opened with O_PATH; almost nothing can be done with it */
142 #define FMODE_PATH ((__force fmode_t)0x4000)
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)
153 #define FMODE_OPENED ((__force fmode_t)0x80000)
154 #define FMODE_CREATED ((__force fmode_t)0x100000)
156 /* File is stream-like */
157 #define FMODE_STREAM ((__force fmode_t)0x200000)
159 /* File supports DIRECT IO */
160 #define FMODE_CAN_ODIRECT ((__force fmode_t)0x400000)
162 #define FMODE_NOREUSE ((__force fmode_t)0x800000)
164 /* File supports non-exclusive O_DIRECT writes from multiple threads */
165 #define FMODE_DIO_PARALLEL_WRITE ((__force fmode_t)0x1000000)
167 /* File is embedded in backing_file object */
168 #define FMODE_BACKING ((__force fmode_t)0x2000000)
170 /* File was opened by fanotify and shouldn't generate fanotify events */
171 #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
173 /* File is capable of returning -EAGAIN if I/O will block */
174 #define FMODE_NOWAIT ((__force fmode_t)0x8000000)
176 /* File represents mount that needs unmounting */
177 #define FMODE_NEED_UNMOUNT ((__force fmode_t)0x10000000)
179 /* File does not contribute to nr_files count */
180 #define FMODE_NOACCOUNT ((__force fmode_t)0x20000000)
182 /* File supports async buffered reads */
183 #define FMODE_BUF_RASYNC ((__force fmode_t)0x40000000)
185 /* File supports async nowait buffered writes */
186 #define FMODE_BUF_WASYNC ((__force fmode_t)0x80000000)
189 * Attribute flags. These should be or-ed together to figure out what
192 #define ATTR_MODE (1 << 0)
193 #define ATTR_UID (1 << 1)
194 #define ATTR_GID (1 << 2)
195 #define ATTR_SIZE (1 << 3)
196 #define ATTR_ATIME (1 << 4)
197 #define ATTR_MTIME (1 << 5)
198 #define ATTR_CTIME (1 << 6)
199 #define ATTR_ATIME_SET (1 << 7)
200 #define ATTR_MTIME_SET (1 << 8)
201 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
202 #define ATTR_KILL_SUID (1 << 11)
203 #define ATTR_KILL_SGID (1 << 12)
204 #define ATTR_FILE (1 << 13)
205 #define ATTR_KILL_PRIV (1 << 14)
206 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
207 #define ATTR_TIMES_SET (1 << 16)
208 #define ATTR_TOUCH (1 << 17)
211 * Whiteout is represented by a char device. The following constants define the
212 * mode and device number to use.
214 #define WHITEOUT_MODE 0
215 #define WHITEOUT_DEV 0
218 * This is the Inode Attributes structure, used for notify_change(). It
219 * uses the above definitions as flags, to know which values have changed.
220 * Also, in this manner, a Filesystem can look at only the values it cares
221 * about. Basically, these are the attributes that the VFS layer can
222 * request to change from the FS layer.
224 * Derek Atkins <warlord@MIT.EDU> 94-10-20
227 unsigned int ia_valid;
230 * The two anonymous unions wrap structures with the same member.
232 * Filesystems raising FS_ALLOW_IDMAP need to use ia_vfs{g,u}id which
233 * are a dedicated type requiring the filesystem to use the dedicated
234 * helpers. Other filesystem can continue to use ia_{g,u}id until they
237 * They always contain the same value. In other words FS_ALLOW_IDMAP
238 * pass down the same value on idmapped mounts as they would on regular
250 struct timespec64 ia_atime;
251 struct timespec64 ia_mtime;
252 struct timespec64 ia_ctime;
255 * Not an attribute, but an auxiliary info for filesystems wanting to
256 * implement an ftruncate() like method. NOTE: filesystem should
257 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
259 struct file *ia_file;
263 * Includes for diskquotas.
265 #include <linux/quota.h>
268 * Maximum number of layers of fs stack. Needs to be limited to
269 * prevent kernel stack overflow
271 #define FILESYSTEM_MAX_STACK_DEPTH 2
274 * enum positive_aop_returns - aop return codes with specific semantics
276 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
277 * completed, that the page is still locked, and
278 * should be considered active. The VM uses this hint
279 * to return the page to the active list -- it won't
280 * be a candidate for writeback again in the near
281 * future. Other callers must be careful to unlock
282 * the page if they get this return. Returned by
285 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
286 * unlocked it and the page might have been truncated.
287 * The caller should back up to acquiring a new page and
288 * trying again. The aop will be taking reasonable
289 * precautions not to livelock. If the caller held a page
290 * reference, it should drop it before retrying. Returned
293 * address_space_operation functions return these large constants to indicate
294 * special semantics to the caller. These are much larger than the bytes in a
295 * page to allow for functions that return the number of bytes operated on in a
299 enum positive_aop_returns {
300 AOP_WRITEPAGE_ACTIVATE = 0x80000,
301 AOP_TRUNCATED_PAGE = 0x80001,
305 * oh the beauties of C type declarations.
308 struct address_space;
309 struct writeback_control;
310 struct readahead_control;
313 * Write life time hint values.
314 * Stored in struct inode as u8.
317 WRITE_LIFE_NOT_SET = 0,
318 WRITE_LIFE_NONE = RWH_WRITE_LIFE_NONE,
319 WRITE_LIFE_SHORT = RWH_WRITE_LIFE_SHORT,
320 WRITE_LIFE_MEDIUM = RWH_WRITE_LIFE_MEDIUM,
321 WRITE_LIFE_LONG = RWH_WRITE_LIFE_LONG,
322 WRITE_LIFE_EXTREME = RWH_WRITE_LIFE_EXTREME,
325 /* Match RWF_* bits to IOCB bits */
326 #define IOCB_HIPRI (__force int) RWF_HIPRI
327 #define IOCB_DSYNC (__force int) RWF_DSYNC
328 #define IOCB_SYNC (__force int) RWF_SYNC
329 #define IOCB_NOWAIT (__force int) RWF_NOWAIT
330 #define IOCB_APPEND (__force int) RWF_APPEND
332 /* non-RWF related bits - start at 16 */
333 #define IOCB_EVENTFD (1 << 16)
334 #define IOCB_DIRECT (1 << 17)
335 #define IOCB_WRITE (1 << 18)
336 /* iocb->ki_waitq is valid */
337 #define IOCB_WAITQ (1 << 19)
338 #define IOCB_NOIO (1 << 20)
339 /* can use bio alloc cache */
340 #define IOCB_ALLOC_CACHE (1 << 21)
342 * IOCB_DIO_CALLER_COMP can be set by the iocb owner, to indicate that the
343 * iocb completion can be passed back to the owner for execution from a safe
344 * context rather than needing to be punted through a workqueue. If this
345 * flag is set, the bio completion handling may set iocb->dio_complete to a
346 * handler function and iocb->private to context information for that handler.
347 * The issuer should call the handler with that context information from task
348 * context to complete the processing of the iocb. Note that while this
349 * provides a task context for the dio_complete() callback, it should only be
350 * used on the completion side for non-IO generating completions. It's fine to
351 * call blocking functions from this callback, but they should not wait for
352 * unrelated IO (like cache flushing, new IO generation, etc).
354 #define IOCB_DIO_CALLER_COMP (1 << 22)
355 /* kiocb is a read or write operation submitted by fs/aio.c. */
356 #define IOCB_AIO_RW (1 << 23)
358 /* for use in trace events */
359 #define TRACE_IOCB_STRINGS \
360 { IOCB_HIPRI, "HIPRI" }, \
361 { IOCB_DSYNC, "DSYNC" }, \
362 { IOCB_SYNC, "SYNC" }, \
363 { IOCB_NOWAIT, "NOWAIT" }, \
364 { IOCB_APPEND, "APPEND" }, \
365 { IOCB_EVENTFD, "EVENTFD"}, \
366 { IOCB_DIRECT, "DIRECT" }, \
367 { IOCB_WRITE, "WRITE" }, \
368 { IOCB_WAITQ, "WAITQ" }, \
369 { IOCB_NOIO, "NOIO" }, \
370 { IOCB_ALLOC_CACHE, "ALLOC_CACHE" }, \
371 { IOCB_DIO_CALLER_COMP, "CALLER_COMP" }
374 struct file *ki_filp;
376 void (*ki_complete)(struct kiocb *iocb, long ret);
379 u16 ki_ioprio; /* See linux/ioprio.h */
382 * Only used for async buffered reads, where it denotes the
383 * page waitqueue associated with completing the read. Valid
384 * IFF IOCB_WAITQ is set.
386 struct wait_page_queue *ki_waitq;
388 * Can be used for O_DIRECT IO, where the completion handling
389 * is punted back to the issuer of the IO. May only be set
390 * if IOCB_DIO_CALLER_COMP is set by the issuer, and the issuer
391 * must then check for presence of this handler when ki_complete
392 * is invoked. The data passed in to this handler must be
393 * assigned to ->private when dio_complete is assigned.
395 ssize_t (*dio_complete)(void *data);
399 static inline bool is_sync_kiocb(struct kiocb *kiocb)
401 return kiocb->ki_complete == NULL;
404 struct address_space_operations {
405 int (*writepage)(struct page *page, struct writeback_control *wbc);
406 int (*read_folio)(struct file *, struct folio *);
408 /* Write back some dirty pages from this mapping. */
409 int (*writepages)(struct address_space *, struct writeback_control *);
411 /* Mark a folio dirty. Return true if this dirtied it */
412 bool (*dirty_folio)(struct address_space *, struct folio *);
414 void (*readahead)(struct readahead_control *);
416 int (*write_begin)(struct file *, struct address_space *mapping,
417 loff_t pos, unsigned len,
418 struct page **pagep, void **fsdata);
419 int (*write_end)(struct file *, struct address_space *mapping,
420 loff_t pos, unsigned len, unsigned copied,
421 struct page *page, void *fsdata);
423 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
424 sector_t (*bmap)(struct address_space *, sector_t);
425 void (*invalidate_folio) (struct folio *, size_t offset, size_t len);
426 bool (*release_folio)(struct folio *, gfp_t);
427 void (*free_folio)(struct folio *folio);
428 ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
430 * migrate the contents of a folio to the specified target. If
431 * migrate_mode is MIGRATE_ASYNC, it must not block.
433 int (*migrate_folio)(struct address_space *, struct folio *dst,
434 struct folio *src, enum migrate_mode);
435 int (*launder_folio)(struct folio *);
436 bool (*is_partially_uptodate) (struct folio *, size_t from,
438 void (*is_dirty_writeback) (struct folio *, bool *dirty, bool *wb);
439 int (*error_remove_page)(struct address_space *, struct page *);
441 /* swapfile support */
442 int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
444 void (*swap_deactivate)(struct file *file);
445 int (*swap_rw)(struct kiocb *iocb, struct iov_iter *iter);
448 extern const struct address_space_operations empty_aops;
451 * struct address_space - Contents of a cacheable, mappable object.
452 * @host: Owner, either the inode or the block_device.
453 * @i_pages: Cached pages.
454 * @invalidate_lock: Guards coherency between page cache contents and
455 * file offset->disk block mappings in the filesystem during invalidates.
456 * It is also used to block modification of page cache contents through
458 * @gfp_mask: Memory allocation flags to use for allocating pages.
459 * @i_mmap_writable: Number of VM_SHARED, VM_MAYWRITE mappings.
460 * @nr_thps: Number of THPs in the pagecache (non-shmem only).
461 * @i_mmap: Tree of private and shared mappings.
462 * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
463 * @nrpages: Number of page entries, protected by the i_pages lock.
464 * @writeback_index: Writeback starts here.
466 * @flags: Error bits and flags (AS_*).
467 * @wb_err: The most recent error which has occurred.
468 * @private_lock: For use by the owner of the address_space.
469 * @private_list: For use by the owner of the address_space.
470 * @private_data: For use by the owner of the address_space.
472 struct address_space {
474 struct xarray i_pages;
475 struct rw_semaphore invalidate_lock;
477 atomic_t i_mmap_writable;
478 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
479 /* number of thp, only for non-shmem files */
482 struct rb_root_cached i_mmap;
483 unsigned long nrpages;
484 pgoff_t writeback_index;
485 const struct address_space_operations *a_ops;
487 struct rw_semaphore i_mmap_rwsem;
489 spinlock_t private_lock;
490 struct list_head private_list;
492 } __attribute__((aligned(sizeof(long)))) __randomize_layout;
494 * On most architectures that alignment is already the case; but
495 * must be enforced here for CRIS, to let the least significant bit
496 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
499 /* XArray tags, for tagging dirty and writeback pages in the pagecache. */
500 #define PAGECACHE_TAG_DIRTY XA_MARK_0
501 #define PAGECACHE_TAG_WRITEBACK XA_MARK_1
502 #define PAGECACHE_TAG_TOWRITE XA_MARK_2
505 * Returns true if any of the pages in the mapping are marked with the tag.
507 static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
509 return xa_marked(&mapping->i_pages, tag);
512 static inline void i_mmap_lock_write(struct address_space *mapping)
514 down_write(&mapping->i_mmap_rwsem);
517 static inline int i_mmap_trylock_write(struct address_space *mapping)
519 return down_write_trylock(&mapping->i_mmap_rwsem);
522 static inline void i_mmap_unlock_write(struct address_space *mapping)
524 up_write(&mapping->i_mmap_rwsem);
527 static inline int i_mmap_trylock_read(struct address_space *mapping)
529 return down_read_trylock(&mapping->i_mmap_rwsem);
532 static inline void i_mmap_lock_read(struct address_space *mapping)
534 down_read(&mapping->i_mmap_rwsem);
537 static inline void i_mmap_unlock_read(struct address_space *mapping)
539 up_read(&mapping->i_mmap_rwsem);
542 static inline void i_mmap_assert_locked(struct address_space *mapping)
544 lockdep_assert_held(&mapping->i_mmap_rwsem);
547 static inline void i_mmap_assert_write_locked(struct address_space *mapping)
549 lockdep_assert_held_write(&mapping->i_mmap_rwsem);
553 * Might pages of this file be mapped into userspace?
555 static inline int mapping_mapped(struct address_space *mapping)
557 return !RB_EMPTY_ROOT(&mapping->i_mmap.rb_root);
561 * Might pages of this file have been modified in userspace?
562 * Note that i_mmap_writable counts all VM_SHARED, VM_MAYWRITE vmas: do_mmap
563 * marks vma as VM_SHARED if it is shared, and the file was opened for
564 * writing i.e. vma may be mprotected writable even if now readonly.
566 * If i_mmap_writable is negative, no new writable mappings are allowed. You
567 * can only deny writable mappings, if none exists right now.
569 static inline int mapping_writably_mapped(struct address_space *mapping)
571 return atomic_read(&mapping->i_mmap_writable) > 0;
574 static inline int mapping_map_writable(struct address_space *mapping)
576 return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
580 static inline void mapping_unmap_writable(struct address_space *mapping)
582 atomic_dec(&mapping->i_mmap_writable);
585 static inline int mapping_deny_writable(struct address_space *mapping)
587 return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
591 static inline void mapping_allow_writable(struct address_space *mapping)
593 atomic_inc(&mapping->i_mmap_writable);
597 * Use sequence counter to get consistent i_size on 32-bit processors.
599 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
600 #include <linux/seqlock.h>
601 #define __NEED_I_SIZE_ORDERED
602 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
604 #define i_size_ordered_init(inode) do { } while (0)
608 #define ACL_NOT_CACHED ((void *)(-1))
610 * ACL_DONT_CACHE is for stacked filesystems, that rely on underlying fs to
611 * cache the ACL. This also means that ->get_inode_acl() can be called in RCU
612 * mode with the LOOKUP_RCU flag.
614 #define ACL_DONT_CACHE ((void *)(-3))
616 static inline struct posix_acl *
617 uncached_acl_sentinel(struct task_struct *task)
619 return (void *)task + 1;
623 is_uncached_acl(struct posix_acl *acl)
625 return (long)acl & 1;
628 #define IOP_FASTPERM 0x0001
629 #define IOP_LOOKUP 0x0002
630 #define IOP_NOFOLLOW 0x0004
631 #define IOP_XATTR 0x0008
632 #define IOP_DEFAULT_READLINK 0x0010
634 struct fsnotify_mark_connector;
637 * Keep mostly read-only and often accessed (especially for
638 * the RCU path lookup and 'stat' data) fields at the beginning
639 * of the 'struct inode'
643 unsigned short i_opflags;
646 unsigned int i_flags;
648 #ifdef CONFIG_FS_POSIX_ACL
649 struct posix_acl *i_acl;
650 struct posix_acl *i_default_acl;
653 const struct inode_operations *i_op;
654 struct super_block *i_sb;
655 struct address_space *i_mapping;
657 #ifdef CONFIG_SECURITY
661 /* Stat data, not accessed from path walking */
664 * Filesystems may only read i_nlink directly. They shall use the
665 * following functions for modification:
667 * (set|clear|inc|drop)_nlink
668 * inode_(inc|dec)_link_count
671 const unsigned int i_nlink;
672 unsigned int __i_nlink;
676 struct timespec64 __i_atime;
677 struct timespec64 __i_mtime;
678 struct timespec64 __i_ctime; /* use inode_*_ctime accessors! */
679 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
680 unsigned short i_bytes;
685 #ifdef __NEED_I_SIZE_ORDERED
686 seqcount_t i_size_seqcount;
690 unsigned long i_state;
691 struct rw_semaphore i_rwsem;
693 unsigned long dirtied_when; /* jiffies of first dirtying */
694 unsigned long dirtied_time_when;
696 struct hlist_node i_hash;
697 struct list_head i_io_list; /* backing dev IO list */
698 #ifdef CONFIG_CGROUP_WRITEBACK
699 struct bdi_writeback *i_wb; /* the associated cgroup wb */
701 /* foreign inode detection, see wbc_detach_inode() */
703 u16 i_wb_frn_avg_time;
704 u16 i_wb_frn_history;
706 struct list_head i_lru; /* inode LRU list */
707 struct list_head i_sb_list;
708 struct list_head i_wb_list; /* backing dev writeback list */
710 struct hlist_head i_dentry;
711 struct rcu_head i_rcu;
713 atomic64_t i_version;
714 atomic64_t i_sequence; /* see futex */
716 atomic_t i_dio_count;
717 atomic_t i_writecount;
718 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
719 atomic_t i_readcount; /* struct files open RO */
722 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
723 void (*free_inode)(struct inode *);
725 struct file_lock_context *i_flctx;
726 struct address_space i_data;
727 struct list_head i_devices;
729 struct pipe_inode_info *i_pipe;
737 #ifdef CONFIG_FSNOTIFY
738 __u32 i_fsnotify_mask; /* all events this inode cares about */
739 struct fsnotify_mark_connector __rcu *i_fsnotify_marks;
742 #ifdef CONFIG_FS_ENCRYPTION
743 struct fscrypt_inode_info *i_crypt_info;
746 #ifdef CONFIG_FS_VERITY
747 struct fsverity_info *i_verity_info;
750 void *i_private; /* fs or device private pointer */
751 } __randomize_layout;
753 struct timespec64 timestamp_truncate(struct timespec64 t, struct inode *inode);
755 static inline unsigned int i_blocksize(const struct inode *node)
757 return (1 << node->i_blkbits);
760 static inline int inode_unhashed(struct inode *inode)
762 return hlist_unhashed(&inode->i_hash);
766 * __mark_inode_dirty expects inodes to be hashed. Since we don't
767 * want special inodes in the fileset inode space, we make them
768 * appear hashed, but do not put on any lists. hlist_del()
769 * will work fine and require no locking.
771 static inline void inode_fake_hash(struct inode *inode)
773 hlist_add_fake(&inode->i_hash);
777 * inode->i_mutex nesting subclasses for the lock validator:
779 * 0: the object of the current VFS operation
783 * 4: second non-directory
784 * 5: second parent (when locking independent directories in rename)
786 * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
787 * non-directories at once.
789 * The locking order between these classes is
790 * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
792 enum inode_i_mutex_lock_class
802 static inline void inode_lock(struct inode *inode)
804 down_write(&inode->i_rwsem);
807 static inline void inode_unlock(struct inode *inode)
809 up_write(&inode->i_rwsem);
812 static inline void inode_lock_shared(struct inode *inode)
814 down_read(&inode->i_rwsem);
817 static inline void inode_unlock_shared(struct inode *inode)
819 up_read(&inode->i_rwsem);
822 static inline int inode_trylock(struct inode *inode)
824 return down_write_trylock(&inode->i_rwsem);
827 static inline int inode_trylock_shared(struct inode *inode)
829 return down_read_trylock(&inode->i_rwsem);
832 static inline int inode_is_locked(struct inode *inode)
834 return rwsem_is_locked(&inode->i_rwsem);
837 static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
839 down_write_nested(&inode->i_rwsem, subclass);
842 static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass)
844 down_read_nested(&inode->i_rwsem, subclass);
847 static inline void filemap_invalidate_lock(struct address_space *mapping)
849 down_write(&mapping->invalidate_lock);
852 static inline void filemap_invalidate_unlock(struct address_space *mapping)
854 up_write(&mapping->invalidate_lock);
857 static inline void filemap_invalidate_lock_shared(struct address_space *mapping)
859 down_read(&mapping->invalidate_lock);
862 static inline int filemap_invalidate_trylock_shared(
863 struct address_space *mapping)
865 return down_read_trylock(&mapping->invalidate_lock);
868 static inline void filemap_invalidate_unlock_shared(
869 struct address_space *mapping)
871 up_read(&mapping->invalidate_lock);
874 void lock_two_nondirectories(struct inode *, struct inode*);
875 void unlock_two_nondirectories(struct inode *, struct inode*);
877 void filemap_invalidate_lock_two(struct address_space *mapping1,
878 struct address_space *mapping2);
879 void filemap_invalidate_unlock_two(struct address_space *mapping1,
880 struct address_space *mapping2);
884 * NOTE: in a 32bit arch with a preemptable kernel and
885 * an UP compile the i_size_read/write must be atomic
886 * with respect to the local cpu (unlike with preempt disabled),
887 * but they don't need to be atomic with respect to other cpus like in
888 * true SMP (so they need either to either locally disable irq around
889 * the read or for example on x86 they can be still implemented as a
890 * cmpxchg8b without the need of the lock prefix). For SMP compiles
891 * and 64bit archs it makes no difference if preempt is enabled or not.
893 static inline loff_t i_size_read(const struct inode *inode)
895 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
900 seq = read_seqcount_begin(&inode->i_size_seqcount);
901 i_size = inode->i_size;
902 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
904 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
908 i_size = inode->i_size;
912 return inode->i_size;
917 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
918 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
919 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
921 static inline void i_size_write(struct inode *inode, loff_t i_size)
923 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
925 write_seqcount_begin(&inode->i_size_seqcount);
926 inode->i_size = i_size;
927 write_seqcount_end(&inode->i_size_seqcount);
929 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
931 inode->i_size = i_size;
934 inode->i_size = i_size;
938 static inline unsigned iminor(const struct inode *inode)
940 return MINOR(inode->i_rdev);
943 static inline unsigned imajor(const struct inode *inode)
945 return MAJOR(inode->i_rdev);
949 rwlock_t lock; /* protects pid, uid, euid fields */
950 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
951 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
952 kuid_t uid, euid; /* uid/euid of process setting the owner */
953 int signum; /* posix.1b rt signal to be delivered on IO */
957 * struct file_ra_state - Track a file's readahead state.
958 * @start: Where the most recent readahead started.
959 * @size: Number of pages read in the most recent readahead.
960 * @async_size: Numer of pages that were/are not needed immediately
961 * and so were/are genuinely "ahead". Start next readahead when
962 * the first of these pages is accessed.
963 * @ra_pages: Maximum size of a readahead request, copied from the bdi.
964 * @mmap_miss: How many mmap accesses missed in the page cache.
965 * @prev_pos: The last byte in the most recent read request.
967 * When this structure is passed to ->readahead(), the "most recent"
968 * readahead means the current readahead.
970 struct file_ra_state {
973 unsigned int async_size;
974 unsigned int ra_pages;
975 unsigned int mmap_miss;
980 * Check if @index falls in the readahead windows.
982 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
984 return (index >= ra->start &&
985 index < ra->start + ra->size);
989 * f_{lock,count,pos_lock} members can be highly contended and share
990 * the same cacheline. f_{lock,mode} are very frequently used together
991 * and so share the same cacheline as well. The read-mostly
992 * f_{path,inode,op} are kept on a separate cacheline.
996 struct llist_node f_llist;
997 struct rcu_head f_rcuhead;
998 unsigned int f_iocb_flags;
1002 * Protects f_ep, f_flags.
1003 * Must not be taken from IRQ context.
1007 atomic_long_t f_count;
1008 struct mutex f_pos_lock;
1010 unsigned int f_flags;
1011 struct fown_struct f_owner;
1012 const struct cred *f_cred;
1013 struct file_ra_state f_ra;
1015 struct inode *f_inode; /* cached value */
1016 const struct file_operations *f_op;
1019 #ifdef CONFIG_SECURITY
1022 /* needed for tty driver, and maybe others */
1026 /* Used by fs/eventpoll.c to link all the hooks to this file */
1027 struct hlist_head *f_ep;
1028 #endif /* #ifdef CONFIG_EPOLL */
1029 struct address_space *f_mapping;
1031 errseq_t f_sb_err; /* for syncfs */
1032 } __randomize_layout
1033 __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
1035 struct file_handle {
1038 /* file identifier */
1039 unsigned char f_handle[];
1042 static inline struct file *get_file(struct file *f)
1044 atomic_long_inc(&f->f_count);
1048 struct file *get_file_rcu(struct file __rcu **f);
1049 struct file *get_file_active(struct file **f);
1051 #define file_count(x) atomic_long_read(&(x)->f_count)
1053 #define MAX_NON_LFS ((1UL<<31) - 1)
1055 /* Page cache limit. The filesystems should put that into their s_maxbytes
1056 limits, otherwise bad things can happen in VM. */
1057 #if BITS_PER_LONG==32
1058 #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
1059 #elif BITS_PER_LONG==64
1060 #define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
1063 /* legacy typedef, should eventually be removed */
1064 typedef void *fl_owner_t;
1068 /* The following constant reflects the upper bound of the file/locking space */
1070 #define OFFSET_MAX type_max(loff_t)
1071 #define OFFT_OFFSET_MAX type_max(off_t)
1074 extern void send_sigio(struct fown_struct *fown, int fd, int band);
1076 static inline struct inode *file_inode(const struct file *f)
1081 static inline struct dentry *file_dentry(const struct file *file)
1083 return d_real(file->f_path.dentry, file_inode(file));
1086 struct fasync_struct {
1090 struct fasync_struct *fa_next; /* singly linked list */
1091 struct file *fa_file;
1092 struct rcu_head fa_rcu;
1095 #define FASYNC_MAGIC 0x4601
1097 /* SMP safe fasync helpers: */
1098 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1099 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1100 extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1101 extern struct fasync_struct *fasync_alloc(void);
1102 extern void fasync_free(struct fasync_struct *);
1104 /* can be called from interrupts */
1105 extern void kill_fasync(struct fasync_struct **, int, int);
1107 extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1108 extern int f_setown(struct file *filp, int who, int force);
1109 extern void f_delown(struct file *filp);
1110 extern pid_t f_getown(struct file *filp);
1111 extern int send_sigurg(struct fown_struct *fown);
1114 * sb->s_flags. Note that these mirror the equivalent MS_* flags where
1115 * represented in both.
1117 #define SB_RDONLY BIT(0) /* Mount read-only */
1118 #define SB_NOSUID BIT(1) /* Ignore suid and sgid bits */
1119 #define SB_NODEV BIT(2) /* Disallow access to device special files */
1120 #define SB_NOEXEC BIT(3) /* Disallow program execution */
1121 #define SB_SYNCHRONOUS BIT(4) /* Writes are synced at once */
1122 #define SB_MANDLOCK BIT(6) /* Allow mandatory locks on an FS */
1123 #define SB_DIRSYNC BIT(7) /* Directory modifications are synchronous */
1124 #define SB_NOATIME BIT(10) /* Do not update access times. */
1125 #define SB_NODIRATIME BIT(11) /* Do not update directory access times */
1126 #define SB_SILENT BIT(15)
1127 #define SB_POSIXACL BIT(16) /* Supports POSIX ACLs */
1128 #define SB_INLINECRYPT BIT(17) /* Use blk-crypto for encrypted files */
1129 #define SB_KERNMOUNT BIT(22) /* this is a kern_mount call */
1130 #define SB_I_VERSION BIT(23) /* Update inode I_version field */
1131 #define SB_LAZYTIME BIT(25) /* Update the on-disk [acm]times lazily */
1133 /* These sb flags are internal to the kernel */
1134 #define SB_DEAD BIT(21)
1135 #define SB_DYING BIT(24)
1136 #define SB_SUBMOUNT BIT(26)
1137 #define SB_FORCE BIT(27)
1138 #define SB_NOSEC BIT(28)
1139 #define SB_BORN BIT(29)
1140 #define SB_ACTIVE BIT(30)
1141 #define SB_NOUSER BIT(31)
1143 /* These flags relate to encoding and casefolding */
1144 #define SB_ENC_STRICT_MODE_FL (1 << 0)
1146 #define sb_has_strict_encoding(sb) \
1147 (sb->s_encoding_flags & SB_ENC_STRICT_MODE_FL)
1153 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1154 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1155 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1156 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1157 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1160 #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1161 #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1162 #define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
1163 #define SB_I_STABLE_WRITES 0x00000008 /* don't modify blks until WB is done */
1165 /* sb->s_iflags to limit user namespace mounts */
1166 #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
1167 #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
1168 #define SB_I_UNTRUSTED_MOUNTER 0x00000040
1170 #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */
1171 #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */
1172 #define SB_I_TS_EXPIRY_WARNED 0x00000400 /* warned about timestamp range expiry */
1173 #define SB_I_RETIRED 0x00000800 /* superblock shouldn't be reused */
1174 #define SB_I_NOUMASK 0x00001000 /* VFS does not apply umask */
1176 /* Possible states of 'frozen' field */
1178 SB_UNFROZEN = 0, /* FS is unfrozen */
1179 SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1180 SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1181 SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1182 * internal threads if needed) */
1183 SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1186 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1189 unsigned short frozen; /* Is sb frozen? */
1190 unsigned short freeze_holders; /* Who froze fs? */
1191 struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
1194 struct super_block {
1195 struct list_head s_list; /* Keep this first */
1196 dev_t s_dev; /* search index; _not_ kdev_t */
1197 unsigned char s_blocksize_bits;
1198 unsigned long s_blocksize;
1199 loff_t s_maxbytes; /* Max file size */
1200 struct file_system_type *s_type;
1201 const struct super_operations *s_op;
1202 const struct dquot_operations *dq_op;
1203 const struct quotactl_ops *s_qcop;
1204 const struct export_operations *s_export_op;
1205 unsigned long s_flags;
1206 unsigned long s_iflags; /* internal SB_I_* flags */
1207 unsigned long s_magic;
1208 struct dentry *s_root;
1209 struct rw_semaphore s_umount;
1212 #ifdef CONFIG_SECURITY
1215 const struct xattr_handler * const *s_xattr;
1216 #ifdef CONFIG_FS_ENCRYPTION
1217 const struct fscrypt_operations *s_cop;
1218 struct fscrypt_keyring *s_master_keys; /* master crypto keys in use */
1220 #ifdef CONFIG_FS_VERITY
1221 const struct fsverity_operations *s_vop;
1223 #if IS_ENABLED(CONFIG_UNICODE)
1224 struct unicode_map *s_encoding;
1225 __u16 s_encoding_flags;
1227 struct hlist_bl_head s_roots; /* alternate root dentries for NFS */
1228 struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1229 struct block_device *s_bdev;
1230 struct bdev_handle *s_bdev_handle;
1231 struct backing_dev_info *s_bdi;
1232 struct mtd_info *s_mtd;
1233 struct hlist_node s_instances;
1234 unsigned int s_quota_types; /* Bitmask of supported quota types */
1235 struct quota_info s_dquot; /* Diskquota specific options */
1237 struct sb_writers s_writers;
1240 * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
1241 * s_fsnotify_marks together for cache efficiency. They are frequently
1242 * accessed and rarely modified.
1244 void *s_fs_info; /* Filesystem private info */
1246 /* Granularity of c/m/atime in ns (cannot be worse than a second) */
1248 /* Time limits for c/m/atime in seconds */
1249 time64_t s_time_min;
1250 time64_t s_time_max;
1251 #ifdef CONFIG_FSNOTIFY
1252 __u32 s_fsnotify_mask;
1253 struct fsnotify_mark_connector __rcu *s_fsnotify_marks;
1256 char s_id[32]; /* Informational name */
1257 uuid_t s_uuid; /* UUID */
1259 unsigned int s_max_links;
1262 * The next field is for VFS *only*. No filesystems have any business
1263 * even looking at it. You had been warned.
1265 struct mutex s_vfs_rename_mutex; /* Kludge */
1268 * Filesystem subtype. If non-empty the filesystem type field
1269 * in /proc/mounts will be "type.subtype"
1271 const char *s_subtype;
1273 const struct dentry_operations *s_d_op; /* default d_op for dentries */
1275 struct shrinker *s_shrink; /* per-sb shrinker handle */
1277 /* Number of inodes with nlink == 0 but still referenced */
1278 atomic_long_t s_remove_count;
1281 * Number of inode/mount/sb objects that are being watched, note that
1282 * inodes objects are currently double-accounted.
1284 atomic_long_t s_fsnotify_connectors;
1286 /* Read-only state of the superblock is being changed */
1287 int s_readonly_remount;
1289 /* per-sb errseq_t for reporting writeback errors via syncfs */
1292 /* AIO completions deferred from interrupt context */
1293 struct workqueue_struct *s_dio_done_wq;
1294 struct hlist_head s_pins;
1297 * Owning user namespace and default context in which to
1298 * interpret filesystem uids, gids, quotas, device nodes,
1299 * xattrs and security labels.
1301 struct user_namespace *s_user_ns;
1304 * The list_lru structure is essentially just a pointer to a table
1305 * of per-node lru lists, each of which has its own spinlock.
1306 * There is no need to put them into separate cachelines.
1308 struct list_lru s_dentry_lru;
1309 struct list_lru s_inode_lru;
1310 struct rcu_head rcu;
1311 struct work_struct destroy_work;
1313 struct mutex s_sync_lock; /* sync serialisation lock */
1316 * Indicates how deep in a filesystem stack this SB is
1320 /* s_inode_list_lock protects s_inodes */
1321 spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
1322 struct list_head s_inodes; /* all inodes */
1324 spinlock_t s_inode_wblist_lock;
1325 struct list_head s_inodes_wb; /* writeback inodes */
1326 } __randomize_layout;
1328 static inline struct user_namespace *i_user_ns(const struct inode *inode)
1330 return inode->i_sb->s_user_ns;
1333 /* Helper functions so that in most cases filesystems will
1334 * not need to deal directly with kuid_t and kgid_t and can
1335 * instead deal with the raw numeric values that are stored
1336 * in the filesystem.
1338 static inline uid_t i_uid_read(const struct inode *inode)
1340 return from_kuid(i_user_ns(inode), inode->i_uid);
1343 static inline gid_t i_gid_read(const struct inode *inode)
1345 return from_kgid(i_user_ns(inode), inode->i_gid);
1348 static inline void i_uid_write(struct inode *inode, uid_t uid)
1350 inode->i_uid = make_kuid(i_user_ns(inode), uid);
1353 static inline void i_gid_write(struct inode *inode, gid_t gid)
1355 inode->i_gid = make_kgid(i_user_ns(inode), gid);
1359 * i_uid_into_vfsuid - map an inode's i_uid down according to an idmapping
1360 * @idmap: idmap of the mount the inode was found from
1361 * @inode: inode to map
1363 * Return: whe inode's i_uid mapped down according to @idmap.
1364 * If the inode's i_uid has no mapping INVALID_VFSUID is returned.
1366 static inline vfsuid_t i_uid_into_vfsuid(struct mnt_idmap *idmap,
1367 const struct inode *inode)
1369 return make_vfsuid(idmap, i_user_ns(inode), inode->i_uid);
1373 * i_uid_needs_update - check whether inode's i_uid needs to be updated
1374 * @idmap: idmap of the mount the inode was found from
1375 * @attr: the new attributes of @inode
1376 * @inode: the inode to update
1378 * Check whether the $inode's i_uid field needs to be updated taking idmapped
1379 * mounts into account if the filesystem supports it.
1381 * Return: true if @inode's i_uid field needs to be updated, false if not.
1383 static inline bool i_uid_needs_update(struct mnt_idmap *idmap,
1384 const struct iattr *attr,
1385 const struct inode *inode)
1387 return ((attr->ia_valid & ATTR_UID) &&
1388 !vfsuid_eq(attr->ia_vfsuid,
1389 i_uid_into_vfsuid(idmap, inode)));
1393 * i_uid_update - update @inode's i_uid field
1394 * @idmap: idmap of the mount the inode was found from
1395 * @attr: the new attributes of @inode
1396 * @inode: the inode to update
1398 * Safely update @inode's i_uid field translating the vfsuid of any idmapped
1399 * mount into the filesystem kuid.
1401 static inline void i_uid_update(struct mnt_idmap *idmap,
1402 const struct iattr *attr,
1403 struct inode *inode)
1405 if (attr->ia_valid & ATTR_UID)
1406 inode->i_uid = from_vfsuid(idmap, i_user_ns(inode),
1411 * i_gid_into_vfsgid - map an inode's i_gid down according to an idmapping
1412 * @idmap: idmap of the mount the inode was found from
1413 * @inode: inode to map
1415 * Return: the inode's i_gid mapped down according to @idmap.
1416 * If the inode's i_gid has no mapping INVALID_VFSGID is returned.
1418 static inline vfsgid_t i_gid_into_vfsgid(struct mnt_idmap *idmap,
1419 const struct inode *inode)
1421 return make_vfsgid(idmap, i_user_ns(inode), inode->i_gid);
1425 * i_gid_needs_update - check whether inode's i_gid needs to be updated
1426 * @idmap: idmap of the mount the inode was found from
1427 * @attr: the new attributes of @inode
1428 * @inode: the inode to update
1430 * Check whether the $inode's i_gid field needs to be updated taking idmapped
1431 * mounts into account if the filesystem supports it.
1433 * Return: true if @inode's i_gid field needs to be updated, false if not.
1435 static inline bool i_gid_needs_update(struct mnt_idmap *idmap,
1436 const struct iattr *attr,
1437 const struct inode *inode)
1439 return ((attr->ia_valid & ATTR_GID) &&
1440 !vfsgid_eq(attr->ia_vfsgid,
1441 i_gid_into_vfsgid(idmap, inode)));
1445 * i_gid_update - update @inode's i_gid field
1446 * @idmap: idmap of the mount the inode was found from
1447 * @attr: the new attributes of @inode
1448 * @inode: the inode to update
1450 * Safely update @inode's i_gid field translating the vfsgid of any idmapped
1451 * mount into the filesystem kgid.
1453 static inline void i_gid_update(struct mnt_idmap *idmap,
1454 const struct iattr *attr,
1455 struct inode *inode)
1457 if (attr->ia_valid & ATTR_GID)
1458 inode->i_gid = from_vfsgid(idmap, i_user_ns(inode),
1463 * inode_fsuid_set - initialize inode's i_uid field with callers fsuid
1464 * @inode: inode to initialize
1465 * @idmap: idmap of the mount the inode was found from
1467 * Initialize the i_uid field of @inode. If the inode was found/created via
1468 * an idmapped mount map the caller's fsuid according to @idmap.
1470 static inline void inode_fsuid_set(struct inode *inode,
1471 struct mnt_idmap *idmap)
1473 inode->i_uid = mapped_fsuid(idmap, i_user_ns(inode));
1477 * inode_fsgid_set - initialize inode's i_gid field with callers fsgid
1478 * @inode: inode to initialize
1479 * @idmap: idmap of the mount the inode was found from
1481 * Initialize the i_gid field of @inode. If the inode was found/created via
1482 * an idmapped mount map the caller's fsgid according to @idmap.
1484 static inline void inode_fsgid_set(struct inode *inode,
1485 struct mnt_idmap *idmap)
1487 inode->i_gid = mapped_fsgid(idmap, i_user_ns(inode));
1491 * fsuidgid_has_mapping() - check whether caller's fsuid/fsgid is mapped
1492 * @sb: the superblock we want a mapping in
1493 * @idmap: idmap of the relevant mount
1495 * Check whether the caller's fsuid and fsgid have a valid mapping in the
1496 * s_user_ns of the superblock @sb. If the caller is on an idmapped mount map
1497 * the caller's fsuid and fsgid according to the @idmap first.
1499 * Return: true if fsuid and fsgid is mapped, false if not.
1501 static inline bool fsuidgid_has_mapping(struct super_block *sb,
1502 struct mnt_idmap *idmap)
1504 struct user_namespace *fs_userns = sb->s_user_ns;
1508 kuid = mapped_fsuid(idmap, fs_userns);
1509 if (!uid_valid(kuid))
1511 kgid = mapped_fsgid(idmap, fs_userns);
1512 if (!gid_valid(kgid))
1514 return kuid_has_mapping(fs_userns, kuid) &&
1515 kgid_has_mapping(fs_userns, kgid);
1518 struct timespec64 current_time(struct inode *inode);
1519 struct timespec64 inode_set_ctime_current(struct inode *inode);
1521 static inline time64_t inode_get_atime_sec(const struct inode *inode)
1523 return inode->__i_atime.tv_sec;
1526 static inline long inode_get_atime_nsec(const struct inode *inode)
1528 return inode->__i_atime.tv_nsec;
1531 static inline struct timespec64 inode_get_atime(const struct inode *inode)
1533 return inode->__i_atime;
1536 static inline struct timespec64 inode_set_atime_to_ts(struct inode *inode,
1537 struct timespec64 ts)
1539 inode->__i_atime = ts;
1543 static inline struct timespec64 inode_set_atime(struct inode *inode,
1544 time64_t sec, long nsec)
1546 struct timespec64 ts = { .tv_sec = sec,
1548 return inode_set_atime_to_ts(inode, ts);
1551 static inline time64_t inode_get_mtime_sec(const struct inode *inode)
1553 return inode->__i_mtime.tv_sec;
1556 static inline long inode_get_mtime_nsec(const struct inode *inode)
1558 return inode->__i_mtime.tv_nsec;
1561 static inline struct timespec64 inode_get_mtime(const struct inode *inode)
1563 return inode->__i_mtime;
1566 static inline struct timespec64 inode_set_mtime_to_ts(struct inode *inode,
1567 struct timespec64 ts)
1569 inode->__i_mtime = ts;
1573 static inline struct timespec64 inode_set_mtime(struct inode *inode,
1574 time64_t sec, long nsec)
1576 struct timespec64 ts = { .tv_sec = sec,
1578 return inode_set_mtime_to_ts(inode, ts);
1581 static inline time64_t inode_get_ctime_sec(const struct inode *inode)
1583 return inode->__i_ctime.tv_sec;
1586 static inline long inode_get_ctime_nsec(const struct inode *inode)
1588 return inode->__i_ctime.tv_nsec;
1591 static inline struct timespec64 inode_get_ctime(const struct inode *inode)
1593 return inode->__i_ctime;
1596 static inline struct timespec64 inode_set_ctime_to_ts(struct inode *inode,
1597 struct timespec64 ts)
1599 inode->__i_ctime = ts;
1604 * inode_set_ctime - set the ctime in the inode
1605 * @inode: inode in which to set the ctime
1606 * @sec: tv_sec value to set
1607 * @nsec: tv_nsec value to set
1609 * Set the ctime in @inode to { @sec, @nsec }
1611 static inline struct timespec64 inode_set_ctime(struct inode *inode,
1612 time64_t sec, long nsec)
1614 struct timespec64 ts = { .tv_sec = sec,
1617 return inode_set_ctime_to_ts(inode, ts);
1620 struct timespec64 simple_inode_init_ts(struct inode *inode);
1623 * Snapshotting support.
1627 * These are internal functions, please use sb_start_{write,pagefault,intwrite}
1630 static inline void __sb_end_write(struct super_block *sb, int level)
1632 percpu_up_read(sb->s_writers.rw_sem + level-1);
1635 static inline void __sb_start_write(struct super_block *sb, int level)
1637 percpu_down_read(sb->s_writers.rw_sem + level - 1);
1640 static inline bool __sb_start_write_trylock(struct super_block *sb, int level)
1642 return percpu_down_read_trylock(sb->s_writers.rw_sem + level - 1);
1645 #define __sb_writers_acquired(sb, lev) \
1646 percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1647 #define __sb_writers_release(sb, lev) \
1648 percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1650 static inline bool sb_write_started(const struct super_block *sb)
1652 return lockdep_is_held_type(sb->s_writers.rw_sem + SB_FREEZE_WRITE - 1, 1);
1656 * sb_end_write - drop write access to a superblock
1657 * @sb: the super we wrote to
1659 * Decrement number of writers to the filesystem. Wake up possible waiters
1660 * wanting to freeze the filesystem.
1662 static inline void sb_end_write(struct super_block *sb)
1664 __sb_end_write(sb, SB_FREEZE_WRITE);
1668 * sb_end_pagefault - drop write access to a superblock from a page fault
1669 * @sb: the super we wrote to
1671 * Decrement number of processes handling write page fault to the filesystem.
1672 * Wake up possible waiters wanting to freeze the filesystem.
1674 static inline void sb_end_pagefault(struct super_block *sb)
1676 __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1680 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1681 * @sb: the super we wrote to
1683 * Decrement fs-internal number of writers to the filesystem. Wake up possible
1684 * waiters wanting to freeze the filesystem.
1686 static inline void sb_end_intwrite(struct super_block *sb)
1688 __sb_end_write(sb, SB_FREEZE_FS);
1692 * sb_start_write - get write access to a superblock
1693 * @sb: the super we write to
1695 * When a process wants to write data or metadata to a file system (i.e. dirty
1696 * a page or an inode), it should embed the operation in a sb_start_write() -
1697 * sb_end_write() pair to get exclusion against file system freezing. This
1698 * function increments number of writers preventing freezing. If the file
1699 * system is already frozen, the function waits until the file system is
1702 * Since freeze protection behaves as a lock, users have to preserve
1703 * ordering of freeze protection and other filesystem locks. Generally,
1704 * freeze protection should be the outermost lock. In particular, we have:
1707 * -> i_mutex (write path, truncate, directory ops, ...)
1708 * -> s_umount (freeze_super, thaw_super)
1710 static inline void sb_start_write(struct super_block *sb)
1712 __sb_start_write(sb, SB_FREEZE_WRITE);
1715 static inline bool sb_start_write_trylock(struct super_block *sb)
1717 return __sb_start_write_trylock(sb, SB_FREEZE_WRITE);
1721 * sb_start_pagefault - get write access to a superblock from a page fault
1722 * @sb: the super we write to
1724 * When a process starts handling write page fault, it should embed the
1725 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1726 * exclusion against file system freezing. This is needed since the page fault
1727 * is going to dirty a page. This function increments number of running page
1728 * faults preventing freezing. If the file system is already frozen, the
1729 * function waits until the file system is thawed.
1731 * Since page fault freeze protection behaves as a lock, users have to preserve
1732 * ordering of freeze protection and other filesystem locks. It is advised to
1733 * put sb_start_pagefault() close to mmap_lock in lock ordering. Page fault
1734 * handling code implies lock dependency:
1737 * -> sb_start_pagefault
1739 static inline void sb_start_pagefault(struct super_block *sb)
1741 __sb_start_write(sb, SB_FREEZE_PAGEFAULT);
1745 * sb_start_intwrite - get write access to a superblock for internal fs purposes
1746 * @sb: the super we write to
1748 * This is the third level of protection against filesystem freezing. It is
1749 * free for use by a filesystem. The only requirement is that it must rank
1750 * below sb_start_pagefault.
1752 * For example filesystem can call sb_start_intwrite() when starting a
1753 * transaction which somewhat eases handling of freezing for internal sources
1754 * of filesystem changes (internal fs threads, discarding preallocation on file
1757 static inline void sb_start_intwrite(struct super_block *sb)
1759 __sb_start_write(sb, SB_FREEZE_FS);
1762 static inline bool sb_start_intwrite_trylock(struct super_block *sb)
1764 return __sb_start_write_trylock(sb, SB_FREEZE_FS);
1767 bool inode_owner_or_capable(struct mnt_idmap *idmap,
1768 const struct inode *inode);
1771 * VFS helper functions..
1773 int vfs_create(struct mnt_idmap *, struct inode *,
1774 struct dentry *, umode_t, bool);
1775 int vfs_mkdir(struct mnt_idmap *, struct inode *,
1776 struct dentry *, umode_t);
1777 int vfs_mknod(struct mnt_idmap *, struct inode *, struct dentry *,
1779 int vfs_symlink(struct mnt_idmap *, struct inode *,
1780 struct dentry *, const char *);
1781 int vfs_link(struct dentry *, struct mnt_idmap *, struct inode *,
1782 struct dentry *, struct inode **);
1783 int vfs_rmdir(struct mnt_idmap *, struct inode *, struct dentry *);
1784 int vfs_unlink(struct mnt_idmap *, struct inode *, struct dentry *,
1788 * struct renamedata - contains all information required for renaming
1789 * @old_mnt_idmap: idmap of the old mount the inode was found from
1790 * @old_dir: parent of source
1791 * @old_dentry: source
1792 * @new_mnt_idmap: idmap of the new mount the inode was found from
1793 * @new_dir: parent of destination
1794 * @new_dentry: destination
1795 * @delegated_inode: returns an inode needing a delegation break
1796 * @flags: rename flags
1799 struct mnt_idmap *old_mnt_idmap;
1800 struct inode *old_dir;
1801 struct dentry *old_dentry;
1802 struct mnt_idmap *new_mnt_idmap;
1803 struct inode *new_dir;
1804 struct dentry *new_dentry;
1805 struct inode **delegated_inode;
1807 } __randomize_layout;
1809 int vfs_rename(struct renamedata *);
1811 static inline int vfs_whiteout(struct mnt_idmap *idmap,
1812 struct inode *dir, struct dentry *dentry)
1814 return vfs_mknod(idmap, dir, dentry, S_IFCHR | WHITEOUT_MODE,
1818 struct file *kernel_tmpfile_open(struct mnt_idmap *idmap,
1819 const struct path *parentpath,
1820 umode_t mode, int open_flag,
1821 const struct cred *cred);
1822 struct file *kernel_file_open(const struct path *path, int flags,
1823 struct inode *inode, const struct cred *cred);
1825 int vfs_mkobj(struct dentry *, umode_t,
1826 int (*f)(struct dentry *, umode_t, void *),
1829 int vfs_fchown(struct file *file, uid_t user, gid_t group);
1830 int vfs_fchmod(struct file *file, umode_t mode);
1831 int vfs_utimes(const struct path *path, struct timespec64 *times);
1833 extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1835 #ifdef CONFIG_COMPAT
1836 extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
1839 #define compat_ptr_ioctl NULL
1843 * VFS file helper functions.
1845 void inode_init_owner(struct mnt_idmap *idmap, struct inode *inode,
1846 const struct inode *dir, umode_t mode);
1847 extern bool may_open_dev(const struct path *path);
1848 umode_t mode_strip_sgid(struct mnt_idmap *idmap,
1849 const struct inode *dir, umode_t mode);
1852 * This is the "filldir" function type, used by readdir() to let
1853 * the kernel specify what kind of dirent layout it wants to have.
1854 * This allows the kernel to read directories into kernel space or
1855 * to have different dirent layouts depending on the binary type.
1856 * Return 'true' to keep going and 'false' if there are no more entries.
1859 typedef bool (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
1862 struct dir_context {
1868 * These flags let !MMU mmap() govern direct device mapping vs immediate
1869 * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1871 * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1872 * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1873 * NOMMU_MAP_READ: Can be mapped for reading
1874 * NOMMU_MAP_WRITE: Can be mapped for writing
1875 * NOMMU_MAP_EXEC: Can be mapped for execution
1877 #define NOMMU_MAP_COPY 0x00000001
1878 #define NOMMU_MAP_DIRECT 0x00000008
1879 #define NOMMU_MAP_READ VM_MAYREAD
1880 #define NOMMU_MAP_WRITE VM_MAYWRITE
1881 #define NOMMU_MAP_EXEC VM_MAYEXEC
1883 #define NOMMU_VMFLAGS \
1884 (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1887 * These flags control the behavior of the remap_file_range function pointer.
1888 * If it is called with len == 0 that means "remap to end of source file".
1889 * See Documentation/filesystems/vfs.rst for more details about this call.
1891 * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate)
1892 * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request
1894 #define REMAP_FILE_DEDUP (1 << 0)
1895 #define REMAP_FILE_CAN_SHORTEN (1 << 1)
1898 * These flags signal that the caller is ok with altering various aspects of
1899 * the behavior of the remap operation. The changes must be made by the
1900 * implementation; the vfs remap helper functions can take advantage of them.
1901 * Flags in this category exist to preserve the quirky behavior of the hoisted
1902 * btrfs clone/dedupe ioctls.
1904 #define REMAP_FILE_ADVISORY (REMAP_FILE_CAN_SHORTEN)
1907 * These flags control the behavior of vfs_copy_file_range().
1908 * They are not available to the user via syscall.
1910 * COPY_FILE_SPLICE: call splice direct instead of fs clone/copy ops
1912 #define COPY_FILE_SPLICE (1 << 0)
1915 struct io_uring_cmd;
1918 struct file_operations {
1919 struct module *owner;
1920 loff_t (*llseek) (struct file *, loff_t, int);
1921 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1922 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1923 ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1924 ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1925 int (*iopoll)(struct kiocb *kiocb, struct io_comp_batch *,
1926 unsigned int flags);
1927 int (*iterate_shared) (struct file *, struct dir_context *);
1928 __poll_t (*poll) (struct file *, struct poll_table_struct *);
1929 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1930 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1931 int (*mmap) (struct file *, struct vm_area_struct *);
1932 unsigned long mmap_supported_flags;
1933 int (*open) (struct inode *, struct file *);
1934 int (*flush) (struct file *, fl_owner_t id);
1935 int (*release) (struct inode *, struct file *);
1936 int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1937 int (*fasync) (int, struct file *, int);
1938 int (*lock) (struct file *, int, struct file_lock *);
1939 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1940 int (*check_flags)(int);
1941 int (*flock) (struct file *, int, struct file_lock *);
1942 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1943 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1944 void (*splice_eof)(struct file *file);
1945 int (*setlease)(struct file *, int, struct file_lock **, void **);
1946 long (*fallocate)(struct file *file, int mode, loff_t offset,
1948 void (*show_fdinfo)(struct seq_file *m, struct file *f);
1950 unsigned (*mmap_capabilities)(struct file *);
1952 ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
1953 loff_t, size_t, unsigned int);
1954 loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
1955 struct file *file_out, loff_t pos_out,
1956 loff_t len, unsigned int remap_flags);
1957 int (*fadvise)(struct file *, loff_t, loff_t, int);
1958 int (*uring_cmd)(struct io_uring_cmd *ioucmd, unsigned int issue_flags);
1959 int (*uring_cmd_iopoll)(struct io_uring_cmd *, struct io_comp_batch *,
1960 unsigned int poll_flags);
1961 } __randomize_layout;
1963 /* Wrap a directory iterator that needs exclusive inode access */
1964 int wrap_directory_iterator(struct file *, struct dir_context *,
1965 int (*) (struct file *, struct dir_context *));
1966 #define WRAP_DIR_ITER(x) \
1967 static int shared_##x(struct file *file , struct dir_context *ctx) \
1968 { return wrap_directory_iterator(file, ctx, x); }
1970 struct inode_operations {
1971 struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1972 const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
1973 int (*permission) (struct mnt_idmap *, struct inode *, int);
1974 struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);
1976 int (*readlink) (struct dentry *, char __user *,int);
1978 int (*create) (struct mnt_idmap *, struct inode *,struct dentry *,
1980 int (*link) (struct dentry *,struct inode *,struct dentry *);
1981 int (*unlink) (struct inode *,struct dentry *);
1982 int (*symlink) (struct mnt_idmap *, struct inode *,struct dentry *,
1984 int (*mkdir) (struct mnt_idmap *, struct inode *,struct dentry *,
1986 int (*rmdir) (struct inode *,struct dentry *);
1987 int (*mknod) (struct mnt_idmap *, struct inode *,struct dentry *,
1989 int (*rename) (struct mnt_idmap *, struct inode *, struct dentry *,
1990 struct inode *, struct dentry *, unsigned int);
1991 int (*setattr) (struct mnt_idmap *, struct dentry *, struct iattr *);
1992 int (*getattr) (struct mnt_idmap *, const struct path *,
1993 struct kstat *, u32, unsigned int);
1994 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1995 int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1997 int (*update_time)(struct inode *, int);
1998 int (*atomic_open)(struct inode *, struct dentry *,
1999 struct file *, unsigned open_flag,
2000 umode_t create_mode);
2001 int (*tmpfile) (struct mnt_idmap *, struct inode *,
2002 struct file *, umode_t);
2003 struct posix_acl *(*get_acl)(struct mnt_idmap *, struct dentry *,
2005 int (*set_acl)(struct mnt_idmap *, struct dentry *,
2006 struct posix_acl *, int);
2007 int (*fileattr_set)(struct mnt_idmap *idmap,
2008 struct dentry *dentry, struct fileattr *fa);
2009 int (*fileattr_get)(struct dentry *dentry, struct fileattr *fa);
2010 struct offset_ctx *(*get_offset_ctx)(struct inode *inode);
2011 } ____cacheline_aligned;
2013 static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
2014 struct iov_iter *iter)
2016 return file->f_op->read_iter(kio, iter);
2019 static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
2020 struct iov_iter *iter)
2022 return file->f_op->write_iter(kio, iter);
2025 static inline int call_mmap(struct file *file, struct vm_area_struct *vma)
2027 return file->f_op->mmap(file, vma);
2030 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
2031 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
2032 extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
2033 loff_t, size_t, unsigned int);
2034 extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in,
2035 struct file *file_out, loff_t pos_out,
2036 size_t len, unsigned int flags);
2037 int __generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
2038 struct file *file_out, loff_t pos_out,
2039 loff_t *len, unsigned int remap_flags,
2040 const struct iomap_ops *dax_read_ops);
2041 int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
2042 struct file *file_out, loff_t pos_out,
2043 loff_t *count, unsigned int remap_flags);
2044 extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
2045 struct file *file_out, loff_t pos_out,
2046 loff_t len, unsigned int remap_flags);
2047 extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
2048 struct file *file_out, loff_t pos_out,
2049 loff_t len, unsigned int remap_flags);
2050 extern int vfs_dedupe_file_range(struct file *file,
2051 struct file_dedupe_range *same);
2052 extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
2053 struct file *dst_file, loff_t dst_pos,
2054 loff_t len, unsigned int remap_flags);
2056 enum freeze_holder {
2057 FREEZE_HOLDER_KERNEL = (1U << 0),
2058 FREEZE_HOLDER_USERSPACE = (1U << 1),
2061 struct super_operations {
2062 struct inode *(*alloc_inode)(struct super_block *sb);
2063 void (*destroy_inode)(struct inode *);
2064 void (*free_inode)(struct inode *);
2066 void (*dirty_inode) (struct inode *, int flags);
2067 int (*write_inode) (struct inode *, struct writeback_control *wbc);
2068 int (*drop_inode) (struct inode *);
2069 void (*evict_inode) (struct inode *);
2070 void (*put_super) (struct super_block *);
2071 int (*sync_fs)(struct super_block *sb, int wait);
2072 int (*freeze_super) (struct super_block *, enum freeze_holder who);
2073 int (*freeze_fs) (struct super_block *);
2074 int (*thaw_super) (struct super_block *, enum freeze_holder who);
2075 int (*unfreeze_fs) (struct super_block *);
2076 int (*statfs) (struct dentry *, struct kstatfs *);
2077 int (*remount_fs) (struct super_block *, int *, char *);
2078 void (*umount_begin) (struct super_block *);
2080 int (*show_options)(struct seq_file *, struct dentry *);
2081 int (*show_devname)(struct seq_file *, struct dentry *);
2082 int (*show_path)(struct seq_file *, struct dentry *);
2083 int (*show_stats)(struct seq_file *, struct dentry *);
2085 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
2086 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
2087 struct dquot **(*get_dquots)(struct inode *);
2089 long (*nr_cached_objects)(struct super_block *,
2090 struct shrink_control *);
2091 long (*free_cached_objects)(struct super_block *,
2092 struct shrink_control *);
2093 void (*shutdown)(struct super_block *sb);
2097 * Inode flags - they have no relation to superblock flags now
2099 #define S_SYNC (1 << 0) /* Writes are synced at once */
2100 #define S_NOATIME (1 << 1) /* Do not update access times */
2101 #define S_APPEND (1 << 2) /* Append-only file */
2102 #define S_IMMUTABLE (1 << 3) /* Immutable file */
2103 #define S_DEAD (1 << 4) /* removed, but still open directory */
2104 #define S_NOQUOTA (1 << 5) /* Inode is not counted to quota */
2105 #define S_DIRSYNC (1 << 6) /* Directory modifications are synchronous */
2106 #define S_NOCMTIME (1 << 7) /* Do not update file c/mtime */
2107 #define S_SWAPFILE (1 << 8) /* Do not truncate: swapon got its bmaps */
2108 #define S_PRIVATE (1 << 9) /* Inode is fs-internal */
2109 #define S_IMA (1 << 10) /* Inode has an associated IMA struct */
2110 #define S_AUTOMOUNT (1 << 11) /* Automount/referral quasi-directory */
2111 #define S_NOSEC (1 << 12) /* no suid or xattr security attributes */
2112 #ifdef CONFIG_FS_DAX
2113 #define S_DAX (1 << 13) /* Direct Access, avoiding the page cache */
2115 #define S_DAX 0 /* Make all the DAX code disappear */
2117 #define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
2118 #define S_CASEFOLD (1 << 15) /* Casefolded file */
2119 #define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
2120 #define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
2123 * Note that nosuid etc flags are inode-specific: setting some file-system
2124 * flags just means all the inodes inherit those flags by default. It might be
2125 * possible to override it selectively if you really wanted to with some
2126 * ioctl() that is not currently implemented.
2128 * Exception: SB_RDONLY is always applied to the entire file system.
2130 * Unfortunately, it is possible to change a filesystems flags with it mounted
2131 * with files in use. This means that all of the inodes will not have their
2132 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
2133 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
2135 #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
2137 static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags & SB_RDONLY; }
2138 #define IS_RDONLY(inode) sb_rdonly((inode)->i_sb)
2139 #define IS_SYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS) || \
2140 ((inode)->i_flags & S_SYNC))
2141 #define IS_DIRSYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
2142 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
2143 #define IS_MANDLOCK(inode) __IS_FLG(inode, SB_MANDLOCK)
2144 #define IS_NOATIME(inode) __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
2145 #define IS_I_VERSION(inode) __IS_FLG(inode, SB_I_VERSION)
2147 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
2148 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
2149 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
2151 #ifdef CONFIG_FS_POSIX_ACL
2152 #define IS_POSIXACL(inode) __IS_FLG(inode, SB_POSIXACL)
2154 #define IS_POSIXACL(inode) 0
2157 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
2158 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
2159 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
2160 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
2161 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
2162 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
2163 #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
2164 #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
2165 #define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED)
2166 #define IS_CASEFOLDED(inode) ((inode)->i_flags & S_CASEFOLD)
2167 #define IS_VERITY(inode) ((inode)->i_flags & S_VERITY)
2169 #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
2170 (inode)->i_rdev == WHITEOUT_DEV)
2172 static inline bool HAS_UNMAPPED_ID(struct mnt_idmap *idmap,
2173 struct inode *inode)
2175 return !vfsuid_valid(i_uid_into_vfsuid(idmap, inode)) ||
2176 !vfsgid_valid(i_gid_into_vfsgid(idmap, inode));
2179 static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
2181 *kiocb = (struct kiocb) {
2183 .ki_flags = filp->f_iocb_flags,
2184 .ki_ioprio = get_current_ioprio(),
2188 static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
2191 *kiocb = (struct kiocb) {
2193 .ki_flags = kiocb_src->ki_flags,
2194 .ki_ioprio = kiocb_src->ki_ioprio,
2195 .ki_pos = kiocb_src->ki_pos,
2200 * Inode state bits. Protected by inode->i_lock
2202 * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
2203 * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
2205 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
2206 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
2207 * various stages of removing an inode.
2209 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
2211 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
2212 * fdatasync() (unless I_DIRTY_DATASYNC is also set).
2213 * Timestamp updates are the usual cause.
2214 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
2215 * these changes separately from I_DIRTY_SYNC so that we
2216 * don't have to write inode on fdatasync() when only
2217 * e.g. the timestamps have changed.
2218 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
2219 * I_DIRTY_TIME The inode itself has dirty timestamps, and the
2220 * lazytime mount option is enabled. We keep track of this
2221 * separately from I_DIRTY_SYNC in order to implement
2222 * lazytime. This gets cleared if I_DIRTY_INODE
2223 * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. But
2224 * I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already
2225 * in place because writeback might already be in progress
2226 * and we don't want to lose the time update
2227 * I_NEW Serves as both a mutex and completion notification.
2228 * New inodes set I_NEW. If two processes both create
2229 * the same inode, one of them will release its inode and
2230 * wait for I_NEW to be released before returning.
2231 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
2232 * also cause waiting on I_NEW, without I_NEW actually
2233 * being set. find_inode() uses this to prevent returning
2234 * nearly-dead inodes.
2235 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
2236 * is zero. I_FREEING must be set when I_WILL_FREE is
2238 * I_FREEING Set when inode is about to be freed but still has dirty
2239 * pages or buffers attached or the inode itself is still
2241 * I_CLEAR Added by clear_inode(). In this state the inode is
2242 * clean and can be destroyed. Inode keeps I_FREEING.
2244 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
2245 * prohibited for many purposes. iget() must wait for
2246 * the inode to be completely released, then create it
2247 * anew. Other functions will just ignore such inodes,
2248 * if appropriate. I_NEW is used for waiting.
2250 * I_SYNC Writeback of inode is running. The bit is set during
2251 * data writeback, and cleared with a wakeup on the bit
2252 * address once it is done. The bit is also used to pin
2253 * the inode in memory for flusher thread.
2255 * I_REFERENCED Marks the inode as recently references on the LRU list.
2257 * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
2259 * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
2260 * synchronize competing switching instances and to tell
2261 * wb stat updates to grab the i_pages lock. See
2262 * inode_switch_wbs_work_fn() for details.
2264 * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
2265 * and work dirs among overlayfs mounts.
2267 * I_CREATING New object's inode in the middle of setting up.
2269 * I_DONTCACHE Evict inode as soon as it is not used anymore.
2271 * I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
2272 * Used to detect that mark_inode_dirty() should not move
2273 * inode between dirty lists.
2275 * I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
2277 * Q: What is the difference between I_WILL_FREE and I_FREEING?
2279 #define I_DIRTY_SYNC (1 << 0)
2280 #define I_DIRTY_DATASYNC (1 << 1)
2281 #define I_DIRTY_PAGES (1 << 2)
2283 #define I_NEW (1 << __I_NEW)
2284 #define I_WILL_FREE (1 << 4)
2285 #define I_FREEING (1 << 5)
2286 #define I_CLEAR (1 << 6)
2288 #define I_SYNC (1 << __I_SYNC)
2289 #define I_REFERENCED (1 << 8)
2290 #define __I_DIO_WAKEUP 9
2291 #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
2292 #define I_LINKABLE (1 << 10)
2293 #define I_DIRTY_TIME (1 << 11)
2294 #define I_WB_SWITCH (1 << 13)
2295 #define I_OVL_INUSE (1 << 14)
2296 #define I_CREATING (1 << 15)
2297 #define I_DONTCACHE (1 << 16)
2298 #define I_SYNC_QUEUED (1 << 17)
2299 #define I_PINNING_FSCACHE_WB (1 << 18)
2301 #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
2302 #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
2303 #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
2305 extern void __mark_inode_dirty(struct inode *, int);
2306 static inline void mark_inode_dirty(struct inode *inode)
2308 __mark_inode_dirty(inode, I_DIRTY);
2311 static inline void mark_inode_dirty_sync(struct inode *inode)
2313 __mark_inode_dirty(inode, I_DIRTY_SYNC);
2317 * Returns true if the given inode itself only has dirty timestamps (its pages
2318 * may still be dirty) and isn't currently being allocated or freed.
2319 * Filesystems should call this if when writing an inode when lazytime is
2320 * enabled, they want to opportunistically write the timestamps of other inodes
2321 * located very nearby on-disk, e.g. in the same inode block. This returns true
2322 * if the given inode is in need of such an opportunistic update. Requires
2323 * i_lock, or at least later re-checking under i_lock.
2325 static inline bool inode_is_dirtytime_only(struct inode *inode)
2327 return (inode->i_state & (I_DIRTY_TIME | I_NEW |
2328 I_FREEING | I_WILL_FREE)) == I_DIRTY_TIME;
2331 extern void inc_nlink(struct inode *inode);
2332 extern void drop_nlink(struct inode *inode);
2333 extern void clear_nlink(struct inode *inode);
2334 extern void set_nlink(struct inode *inode, unsigned int nlink);
2336 static inline void inode_inc_link_count(struct inode *inode)
2339 mark_inode_dirty(inode);
2342 static inline void inode_dec_link_count(struct inode *inode)
2345 mark_inode_dirty(inode);
2348 enum file_time_flags {
2355 extern bool atime_needs_update(const struct path *, struct inode *);
2356 extern void touch_atime(const struct path *);
2357 int inode_update_time(struct inode *inode, int flags);
2359 static inline void file_accessed(struct file *file)
2361 if (!(file->f_flags & O_NOATIME))
2362 touch_atime(&file->f_path);
2365 extern int file_modified(struct file *file);
2366 int kiocb_modified(struct kiocb *iocb);
2368 int sync_inode_metadata(struct inode *inode, int wait);
2370 struct file_system_type {
2373 #define FS_REQUIRES_DEV 1
2374 #define FS_BINARY_MOUNTDATA 2
2375 #define FS_HAS_SUBTYPE 4
2376 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2377 #define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
2378 #define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
2379 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2380 int (*init_fs_context)(struct fs_context *);
2381 const struct fs_parameter_spec *parameters;
2382 struct dentry *(*mount) (struct file_system_type *, int,
2383 const char *, void *);
2384 void (*kill_sb) (struct super_block *);
2385 struct module *owner;
2386 struct file_system_type * next;
2387 struct hlist_head fs_supers;
2389 struct lock_class_key s_lock_key;
2390 struct lock_class_key s_umount_key;
2391 struct lock_class_key s_vfs_rename_key;
2392 struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
2394 struct lock_class_key i_lock_key;
2395 struct lock_class_key i_mutex_key;
2396 struct lock_class_key invalidate_lock_key;
2397 struct lock_class_key i_mutex_dir_key;
2400 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2402 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
2403 int flags, const char *dev_name, void *data,
2404 int (*fill_super)(struct super_block *, void *, int));
2405 extern struct dentry *mount_single(struct file_system_type *fs_type,
2406 int flags, void *data,
2407 int (*fill_super)(struct super_block *, void *, int));
2408 extern struct dentry *mount_nodev(struct file_system_type *fs_type,
2409 int flags, void *data,
2410 int (*fill_super)(struct super_block *, void *, int));
2411 extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
2412 void retire_super(struct super_block *sb);
2413 void generic_shutdown_super(struct super_block *sb);
2414 void kill_block_super(struct super_block *sb);
2415 void kill_anon_super(struct super_block *sb);
2416 void kill_litter_super(struct super_block *sb);
2417 void deactivate_super(struct super_block *sb);
2418 void deactivate_locked_super(struct super_block *sb);
2419 int set_anon_super(struct super_block *s, void *data);
2420 int set_anon_super_fc(struct super_block *s, struct fs_context *fc);
2421 int get_anon_bdev(dev_t *);
2422 void free_anon_bdev(dev_t);
2423 struct super_block *sget_fc(struct fs_context *fc,
2424 int (*test)(struct super_block *, struct fs_context *),
2425 int (*set)(struct super_block *, struct fs_context *));
2426 struct super_block *sget(struct file_system_type *type,
2427 int (*test)(struct super_block *,void *),
2428 int (*set)(struct super_block *,void *),
2429 int flags, void *data);
2430 struct super_block *sget_dev(struct fs_context *fc, dev_t dev);
2432 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2433 #define fops_get(fops) \
2434 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2435 #define fops_put(fops) \
2436 do { if (fops) module_put((fops)->owner); } while(0)
2438 * This one is to be used *ONLY* from ->open() instances.
2439 * fops must be non-NULL, pinned down *and* module dependencies
2440 * should be sufficient to pin the caller down as well.
2442 #define replace_fops(f, fops) \
2444 struct file *__file = (f); \
2445 fops_put(__file->f_op); \
2446 BUG_ON(!(__file->f_op = (fops))); \
2449 extern int register_filesystem(struct file_system_type *);
2450 extern int unregister_filesystem(struct file_system_type *);
2451 extern int vfs_statfs(const struct path *, struct kstatfs *);
2452 extern int user_statfs(const char __user *, struct kstatfs *);
2453 extern int fd_statfs(int, struct kstatfs *);
2454 int freeze_super(struct super_block *super, enum freeze_holder who);
2455 int thaw_super(struct super_block *super, enum freeze_holder who);
2456 extern __printf(2, 3)
2457 int super_setup_bdi_name(struct super_block *sb, char *fmt, ...);
2458 extern int super_setup_bdi(struct super_block *sb);
2460 extern int current_umask(void);
2462 extern void ihold(struct inode * inode);
2463 extern void iput(struct inode *);
2464 int inode_update_timestamps(struct inode *inode, int flags);
2465 int generic_update_time(struct inode *, int);
2468 extern struct kobject *fs_kobj;
2470 #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2475 const char *name; /* pointer to actual string */
2476 const __user char *uptr; /* original userland pointer */
2478 struct audit_names *aname;
2481 static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
2483 static inline struct mnt_idmap *file_mnt_idmap(const struct file *file)
2485 return mnt_idmap(file->f_path.mnt);
2489 * is_idmapped_mnt - check whether a mount is mapped
2490 * @mnt: the mount to check
2492 * If @mnt has an non @nop_mnt_idmap attached to it then @mnt is mapped.
2494 * Return: true if mount is mapped, false if not.
2496 static inline bool is_idmapped_mnt(const struct vfsmount *mnt)
2498 return mnt_idmap(mnt) != &nop_mnt_idmap;
2501 extern long vfs_truncate(const struct path *, loff_t);
2502 int do_truncate(struct mnt_idmap *, struct dentry *, loff_t start,
2503 unsigned int time_attrs, struct file *filp);
2504 extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2506 extern long do_sys_open(int dfd, const char __user *filename, int flags,
2508 extern struct file *file_open_name(struct filename *, int, umode_t);
2509 extern struct file *filp_open(const char *, int, umode_t);
2510 extern struct file *file_open_root(const struct path *,
2511 const char *, int, umode_t);
2512 static inline struct file *file_open_root_mnt(struct vfsmount *mnt,
2513 const char *name, int flags, umode_t mode)
2515 return file_open_root(&(struct path){.mnt = mnt, .dentry = mnt->mnt_root},
2518 struct file *dentry_open(const struct path *path, int flags,
2519 const struct cred *creds);
2520 struct file *dentry_create(const struct path *path, int flags, umode_t mode,
2521 const struct cred *cred);
2522 struct file *backing_file_open(const struct path *user_path, int flags,
2523 const struct path *real_path,
2524 const struct cred *cred);
2525 struct path *backing_file_user_path(struct file *f);
2528 * file_user_path - get the path to display for memory mapped file
2530 * When mmapping a file on a stackable filesystem (e.g., overlayfs), the file
2531 * stored in ->vm_file is a backing file whose f_inode is on the underlying
2532 * filesystem. When the mapped file path is displayed to user (e.g. via
2533 * /proc/<pid>/maps), this helper should be used to get the path to display
2534 * to the user, which is the path of the fd that user has requested to map.
2536 static inline const struct path *file_user_path(struct file *f)
2538 if (unlikely(f->f_mode & FMODE_BACKING))
2539 return backing_file_user_path(f);
2543 static inline struct file *file_clone_open(struct file *file)
2545 return dentry_open(&file->f_path, file->f_flags, file->f_cred);
2547 extern int filp_close(struct file *, fl_owner_t id);
2549 extern struct filename *getname_flags(const char __user *, int, int *);
2550 extern struct filename *getname_uflags(const char __user *, int);
2551 extern struct filename *getname(const char __user *);
2552 extern struct filename *getname_kernel(const char *);
2553 extern void putname(struct filename *name);
2555 extern int finish_open(struct file *file, struct dentry *dentry,
2556 int (*open)(struct inode *, struct file *));
2557 extern int finish_no_open(struct file *file, struct dentry *dentry);
2559 /* Helper for the simple case when original dentry is used */
2560 static inline int finish_open_simple(struct file *file, int error)
2565 return finish_open(file, file->f_path.dentry, NULL);
2569 extern void __init vfs_caches_init_early(void);
2570 extern void __init vfs_caches_init(void);
2572 extern struct kmem_cache *names_cachep;
2574 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2575 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2577 extern struct super_block *blockdev_superblock;
2578 static inline bool sb_is_blkdev_sb(struct super_block *sb)
2580 return IS_ENABLED(CONFIG_BLOCK) && sb == blockdev_superblock;
2583 void emergency_thaw_all(void);
2584 extern int sync_filesystem(struct super_block *);
2585 extern const struct file_operations def_blk_fops;
2586 extern const struct file_operations def_chr_fops;
2589 #define CHRDEV_MAJOR_MAX 512
2590 /* Marks the bottom of the first segment of free char majors */
2591 #define CHRDEV_MAJOR_DYN_END 234
2592 /* Marks the top and bottom of the second segment of free char majors */
2593 #define CHRDEV_MAJOR_DYN_EXT_START 511
2594 #define CHRDEV_MAJOR_DYN_EXT_END 384
2596 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2597 extern int register_chrdev_region(dev_t, unsigned, const char *);
2598 extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2599 unsigned int count, const char *name,
2600 const struct file_operations *fops);
2601 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2602 unsigned int count, const char *name);
2603 extern void unregister_chrdev_region(dev_t, unsigned);
2604 extern void chrdev_show(struct seq_file *,off_t);
2606 static inline int register_chrdev(unsigned int major, const char *name,
2607 const struct file_operations *fops)
2609 return __register_chrdev(major, 0, 256, name, fops);
2612 static inline void unregister_chrdev(unsigned int major, const char *name)
2614 __unregister_chrdev(major, 0, 256, name);
2617 extern void init_special_inode(struct inode *, umode_t, dev_t);
2619 /* Invalid inode operations -- fs/bad_inode.c */
2620 extern void make_bad_inode(struct inode *);
2621 extern bool is_bad_inode(struct inode *);
2623 extern int __must_check file_fdatawait_range(struct file *file, loff_t lstart,
2625 extern int __must_check file_check_and_advance_wb_err(struct file *file);
2626 extern int __must_check file_write_and_wait_range(struct file *file,
2627 loff_t start, loff_t end);
2629 static inline int file_write_and_wait(struct file *file)
2631 return file_write_and_wait_range(file, 0, LLONG_MAX);
2634 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2636 extern int vfs_fsync(struct file *file, int datasync);
2638 extern int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
2639 unsigned int flags);
2641 static inline bool iocb_is_dsync(const struct kiocb *iocb)
2643 return (iocb->ki_flags & IOCB_DSYNC) ||
2644 IS_SYNC(iocb->ki_filp->f_mapping->host);
2648 * Sync the bytes written if this was a synchronous write. Expect ki_pos
2649 * to already be updated for the write, and will return either the amount
2650 * of bytes passed in, or an error if syncing the file failed.
2652 static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
2654 if (iocb_is_dsync(iocb)) {
2655 int ret = vfs_fsync_range(iocb->ki_filp,
2656 iocb->ki_pos - count, iocb->ki_pos - 1,
2657 (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
2665 extern void emergency_sync(void);
2666 extern void emergency_remount(void);
2669 extern int bmap(struct inode *inode, sector_t *block);
2671 static inline int bmap(struct inode *inode, sector_t *block)
2677 int notify_change(struct mnt_idmap *, struct dentry *,
2678 struct iattr *, struct inode **);
2679 int inode_permission(struct mnt_idmap *, struct inode *, int);
2680 int generic_permission(struct mnt_idmap *, struct inode *, int);
2681 static inline int file_permission(struct file *file, int mask)
2683 return inode_permission(file_mnt_idmap(file),
2684 file_inode(file), mask);
2686 static inline int path_permission(const struct path *path, int mask)
2688 return inode_permission(mnt_idmap(path->mnt),
2689 d_inode(path->dentry), mask);
2691 int __check_sticky(struct mnt_idmap *idmap, struct inode *dir,
2692 struct inode *inode);
2694 static inline bool execute_ok(struct inode *inode)
2696 return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2699 static inline bool inode_wrong_type(const struct inode *inode, umode_t mode)
2701 return (inode->i_mode ^ mode) & S_IFMT;
2705 * file_start_write - get write access to a superblock for regular file io
2706 * @file: the file we want to write to
2708 * This is a variant of sb_start_write() which is a noop on non-regualr file.
2709 * Should be matched with a call to file_end_write().
2711 static inline void file_start_write(struct file *file)
2713 if (!S_ISREG(file_inode(file)->i_mode))
2715 sb_start_write(file_inode(file)->i_sb);
2718 static inline bool file_start_write_trylock(struct file *file)
2720 if (!S_ISREG(file_inode(file)->i_mode))
2722 return sb_start_write_trylock(file_inode(file)->i_sb);
2726 * file_end_write - drop write access to a superblock of a regular file
2727 * @file: the file we wrote to
2729 * Should be matched with a call to file_start_write().
2731 static inline void file_end_write(struct file *file)
2733 if (!S_ISREG(file_inode(file)->i_mode))
2735 sb_end_write(file_inode(file)->i_sb);
2739 * kiocb_start_write - get write access to a superblock for async file io
2740 * @iocb: the io context we want to submit the write with
2742 * This is a variant of sb_start_write() for async io submission.
2743 * Should be matched with a call to kiocb_end_write().
2745 static inline void kiocb_start_write(struct kiocb *iocb)
2747 struct inode *inode = file_inode(iocb->ki_filp);
2749 sb_start_write(inode->i_sb);
2751 * Fool lockdep by telling it the lock got released so that it
2752 * doesn't complain about the held lock when we return to userspace.
2754 __sb_writers_release(inode->i_sb, SB_FREEZE_WRITE);
2758 * kiocb_end_write - drop write access to a superblock after async file io
2759 * @iocb: the io context we sumbitted the write with
2761 * Should be matched with a call to kiocb_start_write().
2763 static inline void kiocb_end_write(struct kiocb *iocb)
2765 struct inode *inode = file_inode(iocb->ki_filp);
2768 * Tell lockdep we inherited freeze protection from submission thread.
2770 __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
2771 sb_end_write(inode->i_sb);
2775 * This is used for regular files where some users -- especially the
2776 * currently executed binary in a process, previously handled via
2777 * VM_DENYWRITE -- cannot handle concurrent write (and maybe mmap
2778 * read-write shared) accesses.
2780 * get_write_access() gets write permission for a file.
2781 * put_write_access() releases this write permission.
2782 * deny_write_access() denies write access to a file.
2783 * allow_write_access() re-enables write access to a file.
2785 * The i_writecount field of an inode can have the following values:
2786 * 0: no write access, no denied write access
2787 * < 0: (-i_writecount) users that denied write access to the file.
2788 * > 0: (i_writecount) users that have write access to the file.
2790 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2791 * except for the cases where we don't hold i_writecount yet. Then we need to
2792 * use {get,deny}_write_access() - these functions check the sign and refuse
2793 * to do the change if sign is wrong.
2795 static inline int get_write_access(struct inode *inode)
2797 return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2799 static inline int deny_write_access(struct file *file)
2801 struct inode *inode = file_inode(file);
2802 return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2804 static inline void put_write_access(struct inode * inode)
2806 atomic_dec(&inode->i_writecount);
2808 static inline void allow_write_access(struct file *file)
2811 atomic_inc(&file_inode(file)->i_writecount);
2813 static inline bool inode_is_open_for_write(const struct inode *inode)
2815 return atomic_read(&inode->i_writecount) > 0;
2818 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
2819 static inline void i_readcount_dec(struct inode *inode)
2821 BUG_ON(atomic_dec_return(&inode->i_readcount) < 0);
2823 static inline void i_readcount_inc(struct inode *inode)
2825 atomic_inc(&inode->i_readcount);
2828 static inline void i_readcount_dec(struct inode *inode)
2832 static inline void i_readcount_inc(struct inode *inode)
2837 extern int do_pipe_flags(int *, int);
2839 extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
2840 ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos);
2841 extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *);
2842 extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *);
2843 extern struct file * open_exec(const char *);
2845 /* fs/dcache.c -- generic fs support functions */
2846 extern bool is_subdir(struct dentry *, struct dentry *);
2847 extern bool path_is_under(const struct path *, const struct path *);
2849 extern char *file_path(struct file *, char *, int);
2851 #include <linux/err.h>
2853 /* needed for stackable file system support */
2854 extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2856 extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2858 extern int inode_init_always(struct super_block *, struct inode *);
2859 extern void inode_init_once(struct inode *);
2860 extern void address_space_init_once(struct address_space *mapping);
2861 extern struct inode * igrab(struct inode *);
2862 extern ino_t iunique(struct super_block *, ino_t);
2863 extern int inode_needs_sync(struct inode *inode);
2864 extern int generic_delete_inode(struct inode *inode);
2865 static inline int generic_drop_inode(struct inode *inode)
2867 return !inode->i_nlink || inode_unhashed(inode);
2869 extern void d_mark_dontcache(struct inode *inode);
2871 extern struct inode *ilookup5_nowait(struct super_block *sb,
2872 unsigned long hashval, int (*test)(struct inode *, void *),
2874 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2875 int (*test)(struct inode *, void *), void *data);
2876 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2878 extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
2879 int (*test)(struct inode *, void *),
2880 int (*set)(struct inode *, void *),
2882 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2883 extern struct inode * iget_locked(struct super_block *, unsigned long);
2884 extern struct inode *find_inode_nowait(struct super_block *,
2886 int (*match)(struct inode *,
2887 unsigned long, void *),
2889 extern struct inode *find_inode_rcu(struct super_block *, unsigned long,
2890 int (*)(struct inode *, void *), void *);
2891 extern struct inode *find_inode_by_ino_rcu(struct super_block *, unsigned long);
2892 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2893 extern int insert_inode_locked(struct inode *);
2894 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2895 extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2897 static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2899 extern void unlock_new_inode(struct inode *);
2900 extern void discard_new_inode(struct inode *);
2901 extern unsigned int get_next_ino(void);
2902 extern void evict_inodes(struct super_block *sb);
2903 void dump_mapping(const struct address_space *);
2906 * Userspace may rely on the inode number being non-zero. For example, glibc
2907 * simply ignores files with zero i_ino in unlink() and other places.
2909 * As an additional complication, if userspace was compiled with
2910 * _FILE_OFFSET_BITS=32 on a 64-bit kernel we'll only end up reading out the
2911 * lower 32 bits, so we need to check that those aren't zero explicitly. With
2912 * _FILE_OFFSET_BITS=64, this may cause some harmless false-negatives, but
2913 * better safe than sorry.
2915 static inline bool is_zero_ino(ino_t ino)
2917 return (u32)ino == 0;
2920 extern void __iget(struct inode * inode);
2921 extern void iget_failed(struct inode *);
2922 extern void clear_inode(struct inode *);
2923 extern void __destroy_inode(struct inode *);
2924 extern struct inode *new_inode_pseudo(struct super_block *sb);
2925 extern struct inode *new_inode(struct super_block *sb);
2926 extern void free_inode_nonrcu(struct inode *inode);
2927 extern int setattr_should_drop_suidgid(struct mnt_idmap *, struct inode *);
2928 extern int file_remove_privs(struct file *);
2929 int setattr_should_drop_sgid(struct mnt_idmap *idmap,
2930 const struct inode *inode);
2933 * This must be used for allocating filesystems specific inodes to set
2934 * up the inode reclaim context correctly.
2936 static inline void *
2937 alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp)
2939 return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp);
2942 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2943 static inline void insert_inode_hash(struct inode *inode)
2945 __insert_inode_hash(inode, inode->i_ino);
2948 extern void __remove_inode_hash(struct inode *);
2949 static inline void remove_inode_hash(struct inode *inode)
2951 if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
2952 __remove_inode_hash(inode);
2955 extern void inode_sb_list_add(struct inode *inode);
2956 extern void inode_add_lru(struct inode *inode);
2958 extern int sb_set_blocksize(struct super_block *, int);
2959 extern int sb_min_blocksize(struct super_block *, int);
2961 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2962 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2963 extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
2964 int generic_write_checks_count(struct kiocb *iocb, loff_t *count);
2965 extern int generic_write_check_limits(struct file *file, loff_t pos,
2967 extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);
2968 ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *to,
2969 ssize_t already_read);
2970 extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2971 extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
2972 extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
2973 extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
2974 ssize_t generic_perform_write(struct kiocb *, struct iov_iter *);
2975 ssize_t direct_write_fallback(struct kiocb *iocb, struct iov_iter *iter,
2976 ssize_t direct_written, ssize_t buffered_written);
2978 ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
2980 ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
2982 ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb,
2983 struct iov_iter *iter);
2984 ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb,
2985 struct iov_iter *iter);
2988 ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
2989 struct pipe_inode_info *pipe,
2990 size_t len, unsigned int flags);
2991 ssize_t copy_splice_read(struct file *in, loff_t *ppos,
2992 struct pipe_inode_info *pipe,
2993 size_t len, unsigned int flags);
2994 extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
2995 struct file *, loff_t *, size_t, unsigned int);
2996 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
2997 loff_t *opos, size_t len, unsigned int flags);
3001 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
3002 extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
3003 #define no_llseek NULL
3004 extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
3005 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
3006 extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
3007 int whence, loff_t maxsize, loff_t eof);
3008 extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
3009 int whence, loff_t size);
3010 extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
3011 extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
3012 int rw_verify_area(int, struct file *, const loff_t *, size_t);
3013 extern int generic_file_open(struct inode * inode, struct file * filp);
3014 extern int nonseekable_open(struct inode * inode, struct file * filp);
3015 extern int stream_open(struct inode * inode, struct file * filp);
3018 typedef void (dio_submit_t)(struct bio *bio, struct inode *inode,
3019 loff_t file_offset);
3022 /* need locking between buffered and direct access */
3025 /* filesystem does not support filling holes */
3026 DIO_SKIP_HOLES = 0x02,
3029 ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
3030 struct block_device *bdev, struct iov_iter *iter,
3031 get_block_t get_block,
3032 dio_iodone_t end_io,
3035 static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
3036 struct inode *inode,
3037 struct iov_iter *iter,
3038 get_block_t get_block)
3040 return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
3041 get_block, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
3045 void inode_dio_wait(struct inode *inode);
3048 * inode_dio_begin - signal start of a direct I/O requests
3049 * @inode: inode the direct I/O happens on
3051 * This is called once we've finished processing a direct I/O request,
3052 * and is used to wake up callers waiting for direct I/O to be quiesced.
3054 static inline void inode_dio_begin(struct inode *inode)
3056 atomic_inc(&inode->i_dio_count);
3060 * inode_dio_end - signal finish of a direct I/O requests
3061 * @inode: inode the direct I/O happens on
3063 * This is called once we've finished processing a direct I/O request,
3064 * and is used to wake up callers waiting for direct I/O to be quiesced.
3066 static inline void inode_dio_end(struct inode *inode)
3068 if (atomic_dec_and_test(&inode->i_dio_count))
3069 wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
3072 extern void inode_set_flags(struct inode *inode, unsigned int flags,
3075 extern const struct file_operations generic_ro_fops;
3077 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
3079 extern int readlink_copy(char __user *, int, const char *);
3080 extern int page_readlink(struct dentry *, char __user *, int);
3081 extern const char *page_get_link(struct dentry *, struct inode *,
3082 struct delayed_call *);
3083 extern void page_put_link(void *);
3084 extern int page_symlink(struct inode *inode, const char *symname, int len);
3085 extern const struct inode_operations page_symlink_inode_operations;
3086 extern void kfree_link(void *);
3087 void generic_fillattr(struct mnt_idmap *, u32, struct inode *, struct kstat *);
3088 void generic_fill_statx_attr(struct inode *inode, struct kstat *stat);
3089 extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
3090 extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
3091 void __inode_add_bytes(struct inode *inode, loff_t bytes);
3092 void inode_add_bytes(struct inode *inode, loff_t bytes);
3093 void __inode_sub_bytes(struct inode *inode, loff_t bytes);
3094 void inode_sub_bytes(struct inode *inode, loff_t bytes);
3095 static inline loff_t __inode_get_bytes(struct inode *inode)
3097 return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
3099 loff_t inode_get_bytes(struct inode *inode);
3100 void inode_set_bytes(struct inode *inode, loff_t bytes);
3101 const char *simple_get_link(struct dentry *, struct inode *,
3102 struct delayed_call *);
3103 extern const struct inode_operations simple_symlink_inode_operations;
3105 extern int iterate_dir(struct file *, struct dir_context *);
3107 int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
3109 int vfs_fstat(int fd, struct kstat *stat);
3111 static inline int vfs_stat(const char __user *filename, struct kstat *stat)
3113 return vfs_fstatat(AT_FDCWD, filename, stat, 0);
3115 static inline int vfs_lstat(const char __user *name, struct kstat *stat)
3117 return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
3120 extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
3121 extern int vfs_readlink(struct dentry *, char __user *, int);
3123 extern struct file_system_type *get_filesystem(struct file_system_type *fs);
3124 extern void put_filesystem(struct file_system_type *fs);
3125 extern struct file_system_type *get_fs_type(const char *name);
3126 extern struct super_block *get_active_super(struct block_device *bdev);
3127 extern void drop_super(struct super_block *sb);
3128 extern void drop_super_exclusive(struct super_block *sb);
3129 extern void iterate_supers(void (*)(struct super_block *, void *), void *);
3130 extern void iterate_supers_type(struct file_system_type *,
3131 void (*)(struct super_block *, void *), void *);
3133 extern int dcache_dir_open(struct inode *, struct file *);
3134 extern int dcache_dir_close(struct inode *, struct file *);
3135 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
3136 extern int dcache_readdir(struct file *, struct dir_context *);
3137 extern int simple_setattr(struct mnt_idmap *, struct dentry *,
3139 extern int simple_getattr(struct mnt_idmap *, const struct path *,
3140 struct kstat *, u32, unsigned int);
3141 extern int simple_statfs(struct dentry *, struct kstatfs *);
3142 extern int simple_open(struct inode *inode, struct file *file);
3143 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
3144 extern int simple_unlink(struct inode *, struct dentry *);
3145 extern int simple_rmdir(struct inode *, struct dentry *);
3146 void simple_rename_timestamp(struct inode *old_dir, struct dentry *old_dentry,
3147 struct inode *new_dir, struct dentry *new_dentry);
3148 extern int simple_rename_exchange(struct inode *old_dir, struct dentry *old_dentry,
3149 struct inode *new_dir, struct dentry *new_dentry);
3150 extern int simple_rename(struct mnt_idmap *, struct inode *,
3151 struct dentry *, struct inode *, struct dentry *,
3153 extern void simple_recursive_removal(struct dentry *,
3154 void (*callback)(struct dentry *));
3155 extern int noop_fsync(struct file *, loff_t, loff_t, int);
3156 extern ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
3157 extern int simple_empty(struct dentry *);
3158 extern int simple_write_begin(struct file *file, struct address_space *mapping,
3159 loff_t pos, unsigned len,
3160 struct page **pagep, void **fsdata);
3161 extern const struct address_space_operations ram_aops;
3162 extern int always_delete_dentry(const struct dentry *);
3163 extern struct inode *alloc_anon_inode(struct super_block *);
3164 extern int simple_nosetlease(struct file *, int, struct file_lock **, void **);
3165 extern const struct dentry_operations simple_dentry_operations;
3167 extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
3168 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
3169 extern const struct file_operations simple_dir_operations;
3170 extern const struct inode_operations simple_dir_inode_operations;
3171 extern void make_empty_dir_inode(struct inode *inode);
3172 extern bool is_empty_dir_inode(struct inode *inode);
3173 struct tree_descr { const char *name; const struct file_operations *ops; int mode; };
3174 struct dentry *d_alloc_name(struct dentry *, const char *);
3175 extern int simple_fill_super(struct super_block *, unsigned long,
3176 const struct tree_descr *);
3177 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
3178 extern void simple_release_fs(struct vfsmount **mount, int *count);
3180 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
3181 loff_t *ppos, const void *from, size_t available);
3182 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
3183 const void __user *from, size_t count);
3190 void simple_offset_init(struct offset_ctx *octx);
3191 int simple_offset_add(struct offset_ctx *octx, struct dentry *dentry);
3192 void simple_offset_remove(struct offset_ctx *octx, struct dentry *dentry);
3193 int simple_offset_rename_exchange(struct inode *old_dir,
3194 struct dentry *old_dentry,
3195 struct inode *new_dir,
3196 struct dentry *new_dentry);
3197 void simple_offset_destroy(struct offset_ctx *octx);
3199 extern const struct file_operations simple_offset_dir_operations;
3201 extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
3202 extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
3204 extern int generic_check_addressable(unsigned, u64);
3206 extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
3208 int may_setattr(struct mnt_idmap *idmap, struct inode *inode,
3209 unsigned int ia_valid);
3210 int setattr_prepare(struct mnt_idmap *, struct dentry *, struct iattr *);
3211 extern int inode_newsize_ok(const struct inode *, loff_t offset);
3212 void setattr_copy(struct mnt_idmap *, struct inode *inode,
3213 const struct iattr *attr);
3215 extern int file_update_time(struct file *file);
3217 static inline bool vma_is_dax(const struct vm_area_struct *vma)
3219 return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
3222 static inline bool vma_is_fsdax(struct vm_area_struct *vma)
3224 struct inode *inode;
3226 if (!IS_ENABLED(CONFIG_FS_DAX) || !vma->vm_file)
3228 if (!vma_is_dax(vma))
3230 inode = file_inode(vma->vm_file);
3231 if (S_ISCHR(inode->i_mode))
3232 return false; /* device-dax */
3236 static inline int iocb_flags(struct file *file)
3239 if (file->f_flags & O_APPEND)
3241 if (file->f_flags & O_DIRECT)
3243 if (file->f_flags & O_DSYNC)
3245 if (file->f_flags & __O_SYNC)
3250 static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
3252 int kiocb_flags = 0;
3254 /* make sure there's no overlap between RWF and private IOCB flags */
3255 BUILD_BUG_ON((__force int) RWF_SUPPORTED & IOCB_EVENTFD);
3259 if (unlikely(flags & ~RWF_SUPPORTED))
3262 if (flags & RWF_NOWAIT) {
3263 if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
3265 kiocb_flags |= IOCB_NOIO;
3267 kiocb_flags |= (__force int) (flags & RWF_SUPPORTED);
3268 if (flags & RWF_SYNC)
3269 kiocb_flags |= IOCB_DSYNC;
3271 ki->ki_flags |= kiocb_flags;
3275 static inline ino_t parent_ino(struct dentry *dentry)
3280 * Don't strictly need d_lock here? If the parent ino could change
3281 * then surely we'd have a deeper race in the caller?
3283 spin_lock(&dentry->d_lock);
3284 res = dentry->d_parent->d_inode->i_ino;
3285 spin_unlock(&dentry->d_lock);
3289 /* Transaction based IO helpers */
3292 * An argresp is stored in an allocated page and holds the
3293 * size of the argument or response, along with its content
3295 struct simple_transaction_argresp {
3300 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3302 char *simple_transaction_get(struct file *file, const char __user *buf,
3304 ssize_t simple_transaction_read(struct file *file, char __user *buf,
3305 size_t size, loff_t *pos);
3306 int simple_transaction_release(struct inode *inode, struct file *file);
3308 void simple_transaction_set(struct file *file, size_t n);
3311 * simple attribute files
3313 * These attributes behave similar to those in sysfs:
3315 * Writing to an attribute immediately sets a value, an open file can be
3316 * written to multiple times.
3318 * Reading from an attribute creates a buffer from the value that might get
3319 * read with multiple read calls. When the attribute has been read
3320 * completely, no further read calls are possible until the file is opened
3323 * All attributes contain a text representation of a numeric value
3324 * that are accessed with the get() and set() functions.
3326 #define DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, __is_signed) \
3327 static int __fops ## _open(struct inode *inode, struct file *file) \
3329 __simple_attr_check_format(__fmt, 0ull); \
3330 return simple_attr_open(inode, file, __get, __set, __fmt); \
3332 static const struct file_operations __fops = { \
3333 .owner = THIS_MODULE, \
3334 .open = __fops ## _open, \
3335 .release = simple_attr_release, \
3336 .read = simple_attr_read, \
3337 .write = (__is_signed) ? simple_attr_write_signed : simple_attr_write, \
3338 .llseek = generic_file_llseek, \
3341 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3342 DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, false)
3344 #define DEFINE_SIMPLE_ATTRIBUTE_SIGNED(__fops, __get, __set, __fmt) \
3345 DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, true)
3347 static inline __printf(1, 2)
3348 void __simple_attr_check_format(const char *fmt, ...)
3350 /* don't do anything, just let the compiler check the arguments; */
3353 int simple_attr_open(struct inode *inode, struct file *file,
3354 int (*get)(void *, u64 *), int (*set)(void *, u64),
3356 int simple_attr_release(struct inode *inode, struct file *file);
3357 ssize_t simple_attr_read(struct file *file, char __user *buf,
3358 size_t len, loff_t *ppos);
3359 ssize_t simple_attr_write(struct file *file, const char __user *buf,
3360 size_t len, loff_t *ppos);
3361 ssize_t simple_attr_write_signed(struct file *file, const char __user *buf,
3362 size_t len, loff_t *ppos);
3365 int __init list_bdev_fs_names(char *buf, size_t size);
3367 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3368 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3370 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3371 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3372 (flag & __FMODE_NONOTIFY)))
3374 static inline bool is_sxid(umode_t mode)
3376 return mode & (S_ISUID | S_ISGID);
3379 static inline int check_sticky(struct mnt_idmap *idmap,
3380 struct inode *dir, struct inode *inode)
3382 if (!(dir->i_mode & S_ISVTX))
3385 return __check_sticky(idmap, dir, inode);
3388 static inline void inode_has_no_xattr(struct inode *inode)
3390 if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & SB_NOSEC))
3391 inode->i_flags |= S_NOSEC;
3394 static inline bool is_root_inode(struct inode *inode)
3396 return inode == inode->i_sb->s_root->d_inode;
3399 static inline bool dir_emit(struct dir_context *ctx,
3400 const char *name, int namelen,
3401 u64 ino, unsigned type)
3403 return ctx->actor(ctx, name, namelen, ctx->pos, ino, type);
3405 static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
3407 return ctx->actor(ctx, ".", 1, ctx->pos,
3408 file->f_path.dentry->d_inode->i_ino, DT_DIR);
3410 static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
3412 return ctx->actor(ctx, "..", 2, ctx->pos,
3413 parent_ino(file->f_path.dentry), DT_DIR);
3415 static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
3417 if (ctx->pos == 0) {
3418 if (!dir_emit_dot(file, ctx))
3422 if (ctx->pos == 1) {
3423 if (!dir_emit_dotdot(file, ctx))
3429 static inline bool dir_relax(struct inode *inode)
3431 inode_unlock(inode);
3433 return !IS_DEADDIR(inode);
3436 static inline bool dir_relax_shared(struct inode *inode)
3438 inode_unlock_shared(inode);
3439 inode_lock_shared(inode);
3440 return !IS_DEADDIR(inode);
3443 extern bool path_noexec(const struct path *path);
3444 extern void inode_nohighmem(struct inode *inode);
3447 extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len,
3449 extern int generic_fadvise(struct file *file, loff_t offset, loff_t len,
3452 #endif /* _LINUX_FS_H */