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
;
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 /* File is opened with O_NDELAY (only set for block devices) */
123 #define FMODE_NDELAY ((__force fmode_t)0x40)
124 /* File is opened with O_EXCL (only set for block devices) */
125 #define FMODE_EXCL ((__force fmode_t)0x80)
126 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
127 (specialy hack for floppy.c) */
128 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
129 /* 32bit hashes as llseek() offset (for directories) */
130 #define FMODE_32BITHASH ((__force fmode_t)0x200)
131 /* 64bit hashes as llseek() offset (for directories) */
132 #define FMODE_64BITHASH ((__force fmode_t)0x400)
135 * Don't update ctime and mtime.
137 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
138 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
140 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
142 /* Expect random access pattern */
143 #define FMODE_RANDOM ((__force fmode_t)0x1000)
145 /* File is huge (eg. /dev/mem): treat loff_t as unsigned */
146 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
148 /* File is opened with O_PATH; almost nothing can be done with it */
149 #define FMODE_PATH ((__force fmode_t)0x4000)
151 /* File needs atomic accesses to f_pos */
152 #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
153 /* Write access to underlying fs */
154 #define FMODE_WRITER ((__force fmode_t)0x10000)
155 /* Has read method(s) */
156 #define FMODE_CAN_READ ((__force fmode_t)0x20000)
157 /* Has write method(s) */
158 #define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
160 #define FMODE_OPENED ((__force fmode_t)0x80000)
161 #define FMODE_CREATED ((__force fmode_t)0x100000)
163 /* File is stream-like */
164 #define FMODE_STREAM ((__force fmode_t)0x200000)
166 /* File supports DIRECT IO */
167 #define FMODE_CAN_ODIRECT ((__force fmode_t)0x400000)
169 #define FMODE_NOREUSE ((__force fmode_t)0x800000)
171 /* File was opened by fanotify and shouldn't generate fanotify events */
172 #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
174 /* File is capable of returning -EAGAIN if I/O will block */
175 #define FMODE_NOWAIT ((__force fmode_t)0x8000000)
177 /* File represents mount that needs unmounting */
178 #define FMODE_NEED_UNMOUNT ((__force fmode_t)0x10000000)
180 /* File does not contribute to nr_files count */
181 #define FMODE_NOACCOUNT ((__force fmode_t)0x20000000)
183 /* File supports async buffered reads */
184 #define FMODE_BUF_RASYNC ((__force fmode_t)0x40000000)
186 /* File supports async nowait buffered writes */
187 #define FMODE_BUF_WASYNC ((__force fmode_t)0x80000000)
190 * Attribute flags. These should be or-ed together to figure out what
193 #define ATTR_MODE (1 << 0)
194 #define ATTR_UID (1 << 1)
195 #define ATTR_GID (1 << 2)
196 #define ATTR_SIZE (1 << 3)
197 #define ATTR_ATIME (1 << 4)
198 #define ATTR_MTIME (1 << 5)
199 #define ATTR_CTIME (1 << 6)
200 #define ATTR_ATIME_SET (1 << 7)
201 #define ATTR_MTIME_SET (1 << 8)
202 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
203 #define ATTR_KILL_SUID (1 << 11)
204 #define ATTR_KILL_SGID (1 << 12)
205 #define ATTR_FILE (1 << 13)
206 #define ATTR_KILL_PRIV (1 << 14)
207 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
208 #define ATTR_TIMES_SET (1 << 16)
209 #define ATTR_TOUCH (1 << 17)
212 * Whiteout is represented by a char device. The following constants define the
213 * mode and device number to use.
215 #define WHITEOUT_MODE 0
216 #define WHITEOUT_DEV 0
219 * This is the Inode Attributes structure, used for notify_change(). It
220 * uses the above definitions as flags, to know which values have changed.
221 * Also, in this manner, a Filesystem can look at only the values it cares
222 * about. Basically, these are the attributes that the VFS layer can
223 * request to change from the FS layer.
225 * Derek Atkins <warlord@MIT.EDU> 94-10-20
228 unsigned int ia_valid
;
231 * The two anonymous unions wrap structures with the same member.
233 * Filesystems raising FS_ALLOW_IDMAP need to use ia_vfs{g,u}id which
234 * are a dedicated type requiring the filesystem to use the dedicated
235 * helpers. Other filesystem can continue to use ia_{g,u}id until they
238 * They always contain the same value. In other words FS_ALLOW_IDMAP
239 * pass down the same value on idmapped mounts as they would on regular
251 struct timespec64 ia_atime
;
252 struct timespec64 ia_mtime
;
253 struct timespec64 ia_ctime
;
256 * Not an attribute, but an auxiliary info for filesystems wanting to
257 * implement an ftruncate() like method. NOTE: filesystem should
258 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
260 struct file
*ia_file
;
264 * Includes for diskquotas.
266 #include <linux/quota.h>
269 * Maximum number of layers of fs stack. Needs to be limited to
270 * prevent kernel stack overflow
272 #define FILESYSTEM_MAX_STACK_DEPTH 2
275 * enum positive_aop_returns - aop return codes with specific semantics
277 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
278 * completed, that the page is still locked, and
279 * should be considered active. The VM uses this hint
280 * to return the page to the active list -- it won't
281 * be a candidate for writeback again in the near
282 * future. Other callers must be careful to unlock
283 * the page if they get this return. Returned by
286 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
287 * unlocked it and the page might have been truncated.
288 * The caller should back up to acquiring a new page and
289 * trying again. The aop will be taking reasonable
290 * precautions not to livelock. If the caller held a page
291 * reference, it should drop it before retrying. Returned
294 * address_space_operation functions return these large constants to indicate
295 * special semantics to the caller. These are much larger than the bytes in a
296 * page to allow for functions that return the number of bytes operated on in a
300 enum positive_aop_returns
{
301 AOP_WRITEPAGE_ACTIVATE
= 0x80000,
302 AOP_TRUNCATED_PAGE
= 0x80001,
306 * oh the beauties of C type declarations.
309 struct address_space
;
310 struct writeback_control
;
311 struct readahead_control
;
314 * Write life time hint values.
315 * Stored in struct inode as u8.
318 WRITE_LIFE_NOT_SET
= 0,
319 WRITE_LIFE_NONE
= RWH_WRITE_LIFE_NONE
,
320 WRITE_LIFE_SHORT
= RWH_WRITE_LIFE_SHORT
,
321 WRITE_LIFE_MEDIUM
= RWH_WRITE_LIFE_MEDIUM
,
322 WRITE_LIFE_LONG
= RWH_WRITE_LIFE_LONG
,
323 WRITE_LIFE_EXTREME
= RWH_WRITE_LIFE_EXTREME
,
326 /* Match RWF_* bits to IOCB bits */
327 #define IOCB_HIPRI (__force int) RWF_HIPRI
328 #define IOCB_DSYNC (__force int) RWF_DSYNC
329 #define IOCB_SYNC (__force int) RWF_SYNC
330 #define IOCB_NOWAIT (__force int) RWF_NOWAIT
331 #define IOCB_APPEND (__force int) RWF_APPEND
333 /* non-RWF related bits - start at 16 */
334 #define IOCB_EVENTFD (1 << 16)
335 #define IOCB_DIRECT (1 << 17)
336 #define IOCB_WRITE (1 << 18)
337 /* iocb->ki_waitq is valid */
338 #define IOCB_WAITQ (1 << 19)
339 #define IOCB_NOIO (1 << 20)
340 /* can use bio alloc cache */
341 #define IOCB_ALLOC_CACHE (1 << 21)
344 struct file
*ki_filp
;
346 void (*ki_complete
)(struct kiocb
*iocb
, long ret
);
349 u16 ki_ioprio
; /* See linux/ioprio.h */
350 struct wait_page_queue
*ki_waitq
; /* for async buffered IO */
353 static inline bool is_sync_kiocb(struct kiocb
*kiocb
)
355 return kiocb
->ki_complete
== NULL
;
358 struct address_space_operations
{
359 int (*writepage
)(struct page
*page
, struct writeback_control
*wbc
);
360 int (*read_folio
)(struct file
*, struct folio
*);
362 /* Write back some dirty pages from this mapping. */
363 int (*writepages
)(struct address_space
*, struct writeback_control
*);
365 /* Mark a folio dirty. Return true if this dirtied it */
366 bool (*dirty_folio
)(struct address_space
*, struct folio
*);
368 void (*readahead
)(struct readahead_control
*);
370 int (*write_begin
)(struct file
*, struct address_space
*mapping
,
371 loff_t pos
, unsigned len
,
372 struct page
**pagep
, void **fsdata
);
373 int (*write_end
)(struct file
*, struct address_space
*mapping
,
374 loff_t pos
, unsigned len
, unsigned copied
,
375 struct page
*page
, void *fsdata
);
377 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
378 sector_t (*bmap
)(struct address_space
*, sector_t
);
379 void (*invalidate_folio
) (struct folio
*, size_t offset
, size_t len
);
380 bool (*release_folio
)(struct folio
*, gfp_t
);
381 void (*free_folio
)(struct folio
*folio
);
382 ssize_t (*direct_IO
)(struct kiocb
*, struct iov_iter
*iter
);
384 * migrate the contents of a folio to the specified target. If
385 * migrate_mode is MIGRATE_ASYNC, it must not block.
387 int (*migrate_folio
)(struct address_space
*, struct folio
*dst
,
388 struct folio
*src
, enum migrate_mode
);
389 int (*launder_folio
)(struct folio
*);
390 bool (*is_partially_uptodate
) (struct folio
*, size_t from
,
392 void (*is_dirty_writeback
) (struct folio
*, bool *dirty
, bool *wb
);
393 int (*error_remove_page
)(struct address_space
*, struct page
*);
395 /* swapfile support */
396 int (*swap_activate
)(struct swap_info_struct
*sis
, struct file
*file
,
398 void (*swap_deactivate
)(struct file
*file
);
399 int (*swap_rw
)(struct kiocb
*iocb
, struct iov_iter
*iter
);
402 extern const struct address_space_operations empty_aops
;
405 * struct address_space - Contents of a cacheable, mappable object.
406 * @host: Owner, either the inode or the block_device.
407 * @i_pages: Cached pages.
408 * @invalidate_lock: Guards coherency between page cache contents and
409 * file offset->disk block mappings in the filesystem during invalidates.
410 * It is also used to block modification of page cache contents through
412 * @gfp_mask: Memory allocation flags to use for allocating pages.
413 * @i_mmap_writable: Number of VM_SHARED mappings.
414 * @nr_thps: Number of THPs in the pagecache (non-shmem only).
415 * @i_mmap: Tree of private and shared mappings.
416 * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
417 * @nrpages: Number of page entries, protected by the i_pages lock.
418 * @writeback_index: Writeback starts here.
420 * @flags: Error bits and flags (AS_*).
421 * @wb_err: The most recent error which has occurred.
422 * @private_lock: For use by the owner of the address_space.
423 * @private_list: For use by the owner of the address_space.
424 * @private_data: For use by the owner of the address_space.
426 struct address_space
{
428 struct xarray i_pages
;
429 struct rw_semaphore invalidate_lock
;
431 atomic_t i_mmap_writable
;
432 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
433 /* number of thp, only for non-shmem files */
436 struct rb_root_cached i_mmap
;
437 struct rw_semaphore i_mmap_rwsem
;
438 unsigned long nrpages
;
439 pgoff_t writeback_index
;
440 const struct address_space_operations
*a_ops
;
443 spinlock_t private_lock
;
444 struct list_head private_list
;
446 } __attribute__((aligned(sizeof(long)))) __randomize_layout
;
448 * On most architectures that alignment is already the case; but
449 * must be enforced here for CRIS, to let the least significant bit
450 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
453 /* XArray tags, for tagging dirty and writeback pages in the pagecache. */
454 #define PAGECACHE_TAG_DIRTY XA_MARK_0
455 #define PAGECACHE_TAG_WRITEBACK XA_MARK_1
456 #define PAGECACHE_TAG_TOWRITE XA_MARK_2
459 * Returns true if any of the pages in the mapping are marked with the tag.
461 static inline bool mapping_tagged(struct address_space
*mapping
, xa_mark_t tag
)
463 return xa_marked(&mapping
->i_pages
, tag
);
466 static inline void i_mmap_lock_write(struct address_space
*mapping
)
468 down_write(&mapping
->i_mmap_rwsem
);
471 static inline int i_mmap_trylock_write(struct address_space
*mapping
)
473 return down_write_trylock(&mapping
->i_mmap_rwsem
);
476 static inline void i_mmap_unlock_write(struct address_space
*mapping
)
478 up_write(&mapping
->i_mmap_rwsem
);
481 static inline int i_mmap_trylock_read(struct address_space
*mapping
)
483 return down_read_trylock(&mapping
->i_mmap_rwsem
);
486 static inline void i_mmap_lock_read(struct address_space
*mapping
)
488 down_read(&mapping
->i_mmap_rwsem
);
491 static inline void i_mmap_unlock_read(struct address_space
*mapping
)
493 up_read(&mapping
->i_mmap_rwsem
);
496 static inline void i_mmap_assert_locked(struct address_space
*mapping
)
498 lockdep_assert_held(&mapping
->i_mmap_rwsem
);
501 static inline void i_mmap_assert_write_locked(struct address_space
*mapping
)
503 lockdep_assert_held_write(&mapping
->i_mmap_rwsem
);
507 * Might pages of this file be mapped into userspace?
509 static inline int mapping_mapped(struct address_space
*mapping
)
511 return !RB_EMPTY_ROOT(&mapping
->i_mmap
.rb_root
);
515 * Might pages of this file have been modified in userspace?
516 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap
517 * marks vma as VM_SHARED if it is shared, and the file was opened for
518 * writing i.e. vma may be mprotected writable even if now readonly.
520 * If i_mmap_writable is negative, no new writable mappings are allowed. You
521 * can only deny writable mappings, if none exists right now.
523 static inline int mapping_writably_mapped(struct address_space
*mapping
)
525 return atomic_read(&mapping
->i_mmap_writable
) > 0;
528 static inline int mapping_map_writable(struct address_space
*mapping
)
530 return atomic_inc_unless_negative(&mapping
->i_mmap_writable
) ?
534 static inline void mapping_unmap_writable(struct address_space
*mapping
)
536 atomic_dec(&mapping
->i_mmap_writable
);
539 static inline int mapping_deny_writable(struct address_space
*mapping
)
541 return atomic_dec_unless_positive(&mapping
->i_mmap_writable
) ?
545 static inline void mapping_allow_writable(struct address_space
*mapping
)
547 atomic_inc(&mapping
->i_mmap_writable
);
551 * Use sequence counter to get consistent i_size on 32-bit processors.
553 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
554 #include <linux/seqlock.h>
555 #define __NEED_I_SIZE_ORDERED
556 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
558 #define i_size_ordered_init(inode) do { } while (0)
562 #define ACL_NOT_CACHED ((void *)(-1))
564 * ACL_DONT_CACHE is for stacked filesystems, that rely on underlying fs to
565 * cache the ACL. This also means that ->get_inode_acl() can be called in RCU
566 * mode with the LOOKUP_RCU flag.
568 #define ACL_DONT_CACHE ((void *)(-3))
570 static inline struct posix_acl
*
571 uncached_acl_sentinel(struct task_struct
*task
)
573 return (void *)task
+ 1;
577 is_uncached_acl(struct posix_acl
*acl
)
579 return (long)acl
& 1;
582 #define IOP_FASTPERM 0x0001
583 #define IOP_LOOKUP 0x0002
584 #define IOP_NOFOLLOW 0x0004
585 #define IOP_XATTR 0x0008
586 #define IOP_DEFAULT_READLINK 0x0010
588 struct fsnotify_mark_connector
;
591 * Keep mostly read-only and often accessed (especially for
592 * the RCU path lookup and 'stat' data) fields at the beginning
593 * of the 'struct inode'
597 unsigned short i_opflags
;
600 unsigned int i_flags
;
602 #ifdef CONFIG_FS_POSIX_ACL
603 struct posix_acl
*i_acl
;
604 struct posix_acl
*i_default_acl
;
607 const struct inode_operations
*i_op
;
608 struct super_block
*i_sb
;
609 struct address_space
*i_mapping
;
611 #ifdef CONFIG_SECURITY
615 /* Stat data, not accessed from path walking */
618 * Filesystems may only read i_nlink directly. They shall use the
619 * following functions for modification:
621 * (set|clear|inc|drop)_nlink
622 * inode_(inc|dec)_link_count
625 const unsigned int i_nlink
;
626 unsigned int __i_nlink
;
630 struct timespec64 i_atime
;
631 struct timespec64 i_mtime
;
632 struct timespec64 i_ctime
;
633 spinlock_t i_lock
; /* i_blocks, i_bytes, maybe i_size */
634 unsigned short i_bytes
;
639 #ifdef __NEED_I_SIZE_ORDERED
640 seqcount_t i_size_seqcount
;
644 unsigned long i_state
;
645 struct rw_semaphore i_rwsem
;
647 unsigned long dirtied_when
; /* jiffies of first dirtying */
648 unsigned long dirtied_time_when
;
650 struct hlist_node i_hash
;
651 struct list_head i_io_list
; /* backing dev IO list */
652 #ifdef CONFIG_CGROUP_WRITEBACK
653 struct bdi_writeback
*i_wb
; /* the associated cgroup wb */
655 /* foreign inode detection, see wbc_detach_inode() */
657 u16 i_wb_frn_avg_time
;
658 u16 i_wb_frn_history
;
660 struct list_head i_lru
; /* inode LRU list */
661 struct list_head i_sb_list
;
662 struct list_head i_wb_list
; /* backing dev writeback list */
664 struct hlist_head i_dentry
;
665 struct rcu_head i_rcu
;
667 atomic64_t i_version
;
668 atomic64_t i_sequence
; /* see futex */
670 atomic_t i_dio_count
;
671 atomic_t i_writecount
;
672 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
673 atomic_t i_readcount
; /* struct files open RO */
676 const struct file_operations
*i_fop
; /* former ->i_op->default_file_ops */
677 void (*free_inode
)(struct inode
*);
679 struct file_lock_context
*i_flctx
;
680 struct address_space i_data
;
681 struct list_head i_devices
;
683 struct pipe_inode_info
*i_pipe
;
691 #ifdef CONFIG_FSNOTIFY
692 __u32 i_fsnotify_mask
; /* all events this inode cares about */
693 struct fsnotify_mark_connector __rcu
*i_fsnotify_marks
;
696 #ifdef CONFIG_FS_ENCRYPTION
697 struct fscrypt_info
*i_crypt_info
;
700 #ifdef CONFIG_FS_VERITY
701 struct fsverity_info
*i_verity_info
;
704 void *i_private
; /* fs or device private pointer */
705 } __randomize_layout
;
707 struct timespec64
timestamp_truncate(struct timespec64 t
, struct inode
*inode
);
709 static inline unsigned int i_blocksize(const struct inode
*node
)
711 return (1 << node
->i_blkbits
);
714 static inline int inode_unhashed(struct inode
*inode
)
716 return hlist_unhashed(&inode
->i_hash
);
720 * __mark_inode_dirty expects inodes to be hashed. Since we don't
721 * want special inodes in the fileset inode space, we make them
722 * appear hashed, but do not put on any lists. hlist_del()
723 * will work fine and require no locking.
725 static inline void inode_fake_hash(struct inode
*inode
)
727 hlist_add_fake(&inode
->i_hash
);
731 * inode->i_mutex nesting subclasses for the lock validator:
733 * 0: the object of the current VFS operation
737 * 4: second non-directory
738 * 5: second parent (when locking independent directories in rename)
740 * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
741 * non-directories at once.
743 * The locking order between these classes is
744 * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
746 enum inode_i_mutex_lock_class
756 static inline void inode_lock(struct inode
*inode
)
758 down_write(&inode
->i_rwsem
);
761 static inline void inode_unlock(struct inode
*inode
)
763 up_write(&inode
->i_rwsem
);
766 static inline void inode_lock_shared(struct inode
*inode
)
768 down_read(&inode
->i_rwsem
);
771 static inline void inode_unlock_shared(struct inode
*inode
)
773 up_read(&inode
->i_rwsem
);
776 static inline int inode_trylock(struct inode
*inode
)
778 return down_write_trylock(&inode
->i_rwsem
);
781 static inline int inode_trylock_shared(struct inode
*inode
)
783 return down_read_trylock(&inode
->i_rwsem
);
786 static inline int inode_is_locked(struct inode
*inode
)
788 return rwsem_is_locked(&inode
->i_rwsem
);
791 static inline void inode_lock_nested(struct inode
*inode
, unsigned subclass
)
793 down_write_nested(&inode
->i_rwsem
, subclass
);
796 static inline void inode_lock_shared_nested(struct inode
*inode
, unsigned subclass
)
798 down_read_nested(&inode
->i_rwsem
, subclass
);
801 static inline void filemap_invalidate_lock(struct address_space
*mapping
)
803 down_write(&mapping
->invalidate_lock
);
806 static inline void filemap_invalidate_unlock(struct address_space
*mapping
)
808 up_write(&mapping
->invalidate_lock
);
811 static inline void filemap_invalidate_lock_shared(struct address_space
*mapping
)
813 down_read(&mapping
->invalidate_lock
);
816 static inline int filemap_invalidate_trylock_shared(
817 struct address_space
*mapping
)
819 return down_read_trylock(&mapping
->invalidate_lock
);
822 static inline void filemap_invalidate_unlock_shared(
823 struct address_space
*mapping
)
825 up_read(&mapping
->invalidate_lock
);
828 void lock_two_nondirectories(struct inode
*, struct inode
*);
829 void unlock_two_nondirectories(struct inode
*, struct inode
*);
831 void filemap_invalidate_lock_two(struct address_space
*mapping1
,
832 struct address_space
*mapping2
);
833 void filemap_invalidate_unlock_two(struct address_space
*mapping1
,
834 struct address_space
*mapping2
);
838 * NOTE: in a 32bit arch with a preemptable kernel and
839 * an UP compile the i_size_read/write must be atomic
840 * with respect to the local cpu (unlike with preempt disabled),
841 * but they don't need to be atomic with respect to other cpus like in
842 * true SMP (so they need either to either locally disable irq around
843 * the read or for example on x86 they can be still implemented as a
844 * cmpxchg8b without the need of the lock prefix). For SMP compiles
845 * and 64bit archs it makes no difference if preempt is enabled or not.
847 static inline loff_t
i_size_read(const struct inode
*inode
)
849 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
854 seq
= read_seqcount_begin(&inode
->i_size_seqcount
);
855 i_size
= inode
->i_size
;
856 } while (read_seqcount_retry(&inode
->i_size_seqcount
, seq
));
858 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
862 i_size
= inode
->i_size
;
866 return inode
->i_size
;
871 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
872 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
873 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
875 static inline void i_size_write(struct inode
*inode
, loff_t i_size
)
877 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
879 write_seqcount_begin(&inode
->i_size_seqcount
);
880 inode
->i_size
= i_size
;
881 write_seqcount_end(&inode
->i_size_seqcount
);
883 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
885 inode
->i_size
= i_size
;
888 inode
->i_size
= i_size
;
892 static inline unsigned iminor(const struct inode
*inode
)
894 return MINOR(inode
->i_rdev
);
897 static inline unsigned imajor(const struct inode
*inode
)
899 return MAJOR(inode
->i_rdev
);
903 rwlock_t lock
; /* protects pid, uid, euid fields */
904 struct pid
*pid
; /* pid or -pgrp where SIGIO should be sent */
905 enum pid_type pid_type
; /* Kind of process group SIGIO should be sent to */
906 kuid_t uid
, euid
; /* uid/euid of process setting the owner */
907 int signum
; /* posix.1b rt signal to be delivered on IO */
911 * struct file_ra_state - Track a file's readahead state.
912 * @start: Where the most recent readahead started.
913 * @size: Number of pages read in the most recent readahead.
914 * @async_size: Numer of pages that were/are not needed immediately
915 * and so were/are genuinely "ahead". Start next readahead when
916 * the first of these pages is accessed.
917 * @ra_pages: Maximum size of a readahead request, copied from the bdi.
918 * @mmap_miss: How many mmap accesses missed in the page cache.
919 * @prev_pos: The last byte in the most recent read request.
921 * When this structure is passed to ->readahead(), the "most recent"
922 * readahead means the current readahead.
924 struct file_ra_state
{
927 unsigned int async_size
;
928 unsigned int ra_pages
;
929 unsigned int mmap_miss
;
934 * Check if @index falls in the readahead windows.
936 static inline int ra_has_index(struct file_ra_state
*ra
, pgoff_t index
)
938 return (index
>= ra
->start
&&
939 index
< ra
->start
+ ra
->size
);
944 struct llist_node f_llist
;
945 struct rcu_head f_rcuhead
;
946 unsigned int f_iocb_flags
;
949 struct inode
*f_inode
; /* cached value */
950 const struct file_operations
*f_op
;
953 * Protects f_ep, f_flags.
954 * Must not be taken from IRQ context.
957 atomic_long_t f_count
;
958 unsigned int f_flags
;
960 struct mutex f_pos_lock
;
962 struct fown_struct f_owner
;
963 const struct cred
*f_cred
;
964 struct file_ra_state f_ra
;
967 #ifdef CONFIG_SECURITY
970 /* needed for tty driver, and maybe others */
974 /* Used by fs/eventpoll.c to link all the hooks to this file */
975 struct hlist_head
*f_ep
;
976 #endif /* #ifdef CONFIG_EPOLL */
977 struct address_space
*f_mapping
;
979 errseq_t f_sb_err
; /* for syncfs */
981 __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
986 /* file identifier */
987 unsigned char f_handle
[];
990 static inline struct file
*get_file(struct file
*f
)
992 atomic_long_inc(&f
->f_count
);
995 #define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
996 #define file_count(x) atomic_long_read(&(x)->f_count)
998 #define MAX_NON_LFS ((1UL<<31) - 1)
1000 /* Page cache limit. The filesystems should put that into their s_maxbytes
1001 limits, otherwise bad things can happen in VM. */
1002 #if BITS_PER_LONG==32
1003 #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
1004 #elif BITS_PER_LONG==64
1005 #define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
1008 /* legacy typedef, should eventually be removed */
1009 typedef void *fl_owner_t
;
1013 /* The following constant reflects the upper bound of the file/locking space */
1015 #define OFFSET_MAX type_max(loff_t)
1016 #define OFFT_OFFSET_MAX type_max(off_t)
1019 extern void send_sigio(struct fown_struct
*fown
, int fd
, int band
);
1021 static inline struct inode
*file_inode(const struct file
*f
)
1026 static inline struct dentry
*file_dentry(const struct file
*file
)
1028 return d_real(file
->f_path
.dentry
, file_inode(file
));
1031 struct fasync_struct
{
1035 struct fasync_struct
*fa_next
; /* singly linked list */
1036 struct file
*fa_file
;
1037 struct rcu_head fa_rcu
;
1040 #define FASYNC_MAGIC 0x4601
1042 /* SMP safe fasync helpers: */
1043 extern int fasync_helper(int, struct file
*, int, struct fasync_struct
**);
1044 extern struct fasync_struct
*fasync_insert_entry(int, struct file
*, struct fasync_struct
**, struct fasync_struct
*);
1045 extern int fasync_remove_entry(struct file
*, struct fasync_struct
**);
1046 extern struct fasync_struct
*fasync_alloc(void);
1047 extern void fasync_free(struct fasync_struct
*);
1049 /* can be called from interrupts */
1050 extern void kill_fasync(struct fasync_struct
**, int, int);
1052 extern void __f_setown(struct file
*filp
, struct pid
*, enum pid_type
, int force
);
1053 extern int f_setown(struct file
*filp
, unsigned long arg
, int force
);
1054 extern void f_delown(struct file
*filp
);
1055 extern pid_t
f_getown(struct file
*filp
);
1056 extern int send_sigurg(struct fown_struct
*fown
);
1059 * sb->s_flags. Note that these mirror the equivalent MS_* flags where
1060 * represented in both.
1062 #define SB_RDONLY 1 /* Mount read-only */
1063 #define SB_NOSUID 2 /* Ignore suid and sgid bits */
1064 #define SB_NODEV 4 /* Disallow access to device special files */
1065 #define SB_NOEXEC 8 /* Disallow program execution */
1066 #define SB_SYNCHRONOUS 16 /* Writes are synced at once */
1067 #define SB_MANDLOCK 64 /* Allow mandatory locks on an FS */
1068 #define SB_DIRSYNC 128 /* Directory modifications are synchronous */
1069 #define SB_NOATIME 1024 /* Do not update access times. */
1070 #define SB_NODIRATIME 2048 /* Do not update directory access times */
1071 #define SB_SILENT 32768
1072 #define SB_POSIXACL (1<<16) /* VFS does not apply the umask */
1073 #define SB_INLINECRYPT (1<<17) /* Use blk-crypto for encrypted files */
1074 #define SB_KERNMOUNT (1<<22) /* this is a kern_mount call */
1075 #define SB_I_VERSION (1<<23) /* Update inode I_version field */
1076 #define SB_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */
1078 /* These sb flags are internal to the kernel */
1079 #define SB_SUBMOUNT (1<<26)
1080 #define SB_FORCE (1<<27)
1081 #define SB_NOSEC (1<<28)
1082 #define SB_BORN (1<<29)
1083 #define SB_ACTIVE (1<<30)
1084 #define SB_NOUSER (1<<31)
1086 /* These flags relate to encoding and casefolding */
1087 #define SB_ENC_STRICT_MODE_FL (1 << 0)
1089 #define sb_has_strict_encoding(sb) \
1090 (sb->s_encoding_flags & SB_ENC_STRICT_MODE_FL)
1096 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1097 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1098 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1099 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1100 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1103 #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1104 #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1105 #define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
1106 #define SB_I_STABLE_WRITES 0x00000008 /* don't modify blks until WB is done */
1108 /* sb->s_iflags to limit user namespace mounts */
1109 #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
1110 #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020
1111 #define SB_I_UNTRUSTED_MOUNTER 0x00000040
1113 #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */
1114 #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */
1115 #define SB_I_TS_EXPIRY_WARNED 0x00000400 /* warned about timestamp range expiry */
1116 #define SB_I_RETIRED 0x00000800 /* superblock shouldn't be reused */
1118 /* Possible states of 'frozen' field */
1120 SB_UNFROZEN
= 0, /* FS is unfrozen */
1121 SB_FREEZE_WRITE
= 1, /* Writes, dir ops, ioctls frozen */
1122 SB_FREEZE_PAGEFAULT
= 2, /* Page faults stopped as well */
1123 SB_FREEZE_FS
= 3, /* For internal FS use (e.g. to stop
1124 * internal threads if needed) */
1125 SB_FREEZE_COMPLETE
= 4, /* ->freeze_fs finished successfully */
1128 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1131 int frozen
; /* Is sb frozen? */
1132 wait_queue_head_t wait_unfrozen
; /* wait for thaw */
1133 struct percpu_rw_semaphore rw_sem
[SB_FREEZE_LEVELS
];
1136 struct super_block
{
1137 struct list_head s_list
; /* Keep this first */
1138 dev_t s_dev
; /* search index; _not_ kdev_t */
1139 unsigned char s_blocksize_bits
;
1140 unsigned long s_blocksize
;
1141 loff_t s_maxbytes
; /* Max file size */
1142 struct file_system_type
*s_type
;
1143 const struct super_operations
*s_op
;
1144 const struct dquot_operations
*dq_op
;
1145 const struct quotactl_ops
*s_qcop
;
1146 const struct export_operations
*s_export_op
;
1147 unsigned long s_flags
;
1148 unsigned long s_iflags
; /* internal SB_I_* flags */
1149 unsigned long s_magic
;
1150 struct dentry
*s_root
;
1151 struct rw_semaphore s_umount
;
1154 #ifdef CONFIG_SECURITY
1157 const struct xattr_handler
**s_xattr
;
1158 #ifdef CONFIG_FS_ENCRYPTION
1159 const struct fscrypt_operations
*s_cop
;
1160 struct fscrypt_keyring
*s_master_keys
; /* master crypto keys in use */
1162 #ifdef CONFIG_FS_VERITY
1163 const struct fsverity_operations
*s_vop
;
1165 #if IS_ENABLED(CONFIG_UNICODE)
1166 struct unicode_map
*s_encoding
;
1167 __u16 s_encoding_flags
;
1169 struct hlist_bl_head s_roots
; /* alternate root dentries for NFS */
1170 struct list_head s_mounts
; /* list of mounts; _not_ for fs use */
1171 struct block_device
*s_bdev
;
1172 struct backing_dev_info
*s_bdi
;
1173 struct mtd_info
*s_mtd
;
1174 struct hlist_node s_instances
;
1175 unsigned int s_quota_types
; /* Bitmask of supported quota types */
1176 struct quota_info s_dquot
; /* Diskquota specific options */
1178 struct sb_writers s_writers
;
1181 * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
1182 * s_fsnotify_marks together for cache efficiency. They are frequently
1183 * accessed and rarely modified.
1185 void *s_fs_info
; /* Filesystem private info */
1187 /* Granularity of c/m/atime in ns (cannot be worse than a second) */
1189 /* Time limits for c/m/atime in seconds */
1190 time64_t s_time_min
;
1191 time64_t s_time_max
;
1192 #ifdef CONFIG_FSNOTIFY
1193 __u32 s_fsnotify_mask
;
1194 struct fsnotify_mark_connector __rcu
*s_fsnotify_marks
;
1197 char s_id
[32]; /* Informational name */
1198 uuid_t s_uuid
; /* UUID */
1200 unsigned int s_max_links
;
1204 * The next field is for VFS *only*. No filesystems have any business
1205 * even looking at it. You had been warned.
1207 struct mutex s_vfs_rename_mutex
; /* Kludge */
1210 * Filesystem subtype. If non-empty the filesystem type field
1211 * in /proc/mounts will be "type.subtype"
1213 const char *s_subtype
;
1215 const struct dentry_operations
*s_d_op
; /* default d_op for dentries */
1217 struct shrinker s_shrink
; /* per-sb shrinker handle */
1219 /* Number of inodes with nlink == 0 but still referenced */
1220 atomic_long_t s_remove_count
;
1223 * Number of inode/mount/sb objects that are being watched, note that
1224 * inodes objects are currently double-accounted.
1226 atomic_long_t s_fsnotify_connectors
;
1228 /* Being remounted read-only */
1229 int s_readonly_remount
;
1231 /* per-sb errseq_t for reporting writeback errors via syncfs */
1234 /* AIO completions deferred from interrupt context */
1235 struct workqueue_struct
*s_dio_done_wq
;
1236 struct hlist_head s_pins
;
1239 * Owning user namespace and default context in which to
1240 * interpret filesystem uids, gids, quotas, device nodes,
1241 * xattrs and security labels.
1243 struct user_namespace
*s_user_ns
;
1246 * The list_lru structure is essentially just a pointer to a table
1247 * of per-node lru lists, each of which has its own spinlock.
1248 * There is no need to put them into separate cachelines.
1250 struct list_lru s_dentry_lru
;
1251 struct list_lru s_inode_lru
;
1252 struct rcu_head rcu
;
1253 struct work_struct destroy_work
;
1255 struct mutex s_sync_lock
; /* sync serialisation lock */
1258 * Indicates how deep in a filesystem stack this SB is
1262 /* s_inode_list_lock protects s_inodes */
1263 spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp
;
1264 struct list_head s_inodes
; /* all inodes */
1266 spinlock_t s_inode_wblist_lock
;
1267 struct list_head s_inodes_wb
; /* writeback inodes */
1268 } __randomize_layout
;
1270 static inline struct user_namespace
*i_user_ns(const struct inode
*inode
)
1272 return inode
->i_sb
->s_user_ns
;
1275 /* Helper functions so that in most cases filesystems will
1276 * not need to deal directly with kuid_t and kgid_t and can
1277 * instead deal with the raw numeric values that are stored
1278 * in the filesystem.
1280 static inline uid_t
i_uid_read(const struct inode
*inode
)
1282 return from_kuid(i_user_ns(inode
), inode
->i_uid
);
1285 static inline gid_t
i_gid_read(const struct inode
*inode
)
1287 return from_kgid(i_user_ns(inode
), inode
->i_gid
);
1290 static inline void i_uid_write(struct inode
*inode
, uid_t uid
)
1292 inode
->i_uid
= make_kuid(i_user_ns(inode
), uid
);
1295 static inline void i_gid_write(struct inode
*inode
, gid_t gid
)
1297 inode
->i_gid
= make_kgid(i_user_ns(inode
), gid
);
1301 * i_uid_into_vfsuid - map an inode's i_uid down according to an idmapping
1302 * @idmap: idmap of the mount the inode was found from
1303 * @inode: inode to map
1305 * Return: whe inode's i_uid mapped down according to @idmap.
1306 * If the inode's i_uid has no mapping INVALID_VFSUID is returned.
1308 static inline vfsuid_t
i_uid_into_vfsuid(struct mnt_idmap
*idmap
,
1309 const struct inode
*inode
)
1311 return make_vfsuid(idmap
, i_user_ns(inode
), inode
->i_uid
);
1315 * i_uid_needs_update - check whether inode's i_uid needs to be updated
1316 * @idmap: idmap of the mount the inode was found from
1317 * @attr: the new attributes of @inode
1318 * @inode: the inode to update
1320 * Check whether the $inode's i_uid field needs to be updated taking idmapped
1321 * mounts into account if the filesystem supports it.
1323 * Return: true if @inode's i_uid field needs to be updated, false if not.
1325 static inline bool i_uid_needs_update(struct mnt_idmap
*idmap
,
1326 const struct iattr
*attr
,
1327 const struct inode
*inode
)
1329 return ((attr
->ia_valid
& ATTR_UID
) &&
1330 !vfsuid_eq(attr
->ia_vfsuid
,
1331 i_uid_into_vfsuid(idmap
, inode
)));
1335 * i_uid_update - update @inode's i_uid field
1336 * @idmap: idmap of the mount the inode was found from
1337 * @attr: the new attributes of @inode
1338 * @inode: the inode to update
1340 * Safely update @inode's i_uid field translating the vfsuid of any idmapped
1341 * mount into the filesystem kuid.
1343 static inline void i_uid_update(struct mnt_idmap
*idmap
,
1344 const struct iattr
*attr
,
1345 struct inode
*inode
)
1347 if (attr
->ia_valid
& ATTR_UID
)
1348 inode
->i_uid
= from_vfsuid(idmap
, i_user_ns(inode
),
1353 * i_gid_into_vfsgid - map an inode's i_gid down according to an idmapping
1354 * @idmap: idmap of the mount the inode was found from
1355 * @inode: inode to map
1357 * Return: the inode's i_gid mapped down according to @idmap.
1358 * If the inode's i_gid has no mapping INVALID_VFSGID is returned.
1360 static inline vfsgid_t
i_gid_into_vfsgid(struct mnt_idmap
*idmap
,
1361 const struct inode
*inode
)
1363 return make_vfsgid(idmap
, i_user_ns(inode
), inode
->i_gid
);
1367 * i_gid_needs_update - check whether inode's i_gid needs to be updated
1368 * @idmap: idmap of the mount the inode was found from
1369 * @attr: the new attributes of @inode
1370 * @inode: the inode to update
1372 * Check whether the $inode's i_gid field needs to be updated taking idmapped
1373 * mounts into account if the filesystem supports it.
1375 * Return: true if @inode's i_gid field needs to be updated, false if not.
1377 static inline bool i_gid_needs_update(struct mnt_idmap
*idmap
,
1378 const struct iattr
*attr
,
1379 const struct inode
*inode
)
1381 return ((attr
->ia_valid
& ATTR_GID
) &&
1382 !vfsgid_eq(attr
->ia_vfsgid
,
1383 i_gid_into_vfsgid(idmap
, inode
)));
1387 * i_gid_update - update @inode's i_gid field
1388 * @idmap: idmap of the mount the inode was found from
1389 * @attr: the new attributes of @inode
1390 * @inode: the inode to update
1392 * Safely update @inode's i_gid field translating the vfsgid of any idmapped
1393 * mount into the filesystem kgid.
1395 static inline void i_gid_update(struct mnt_idmap
*idmap
,
1396 const struct iattr
*attr
,
1397 struct inode
*inode
)
1399 if (attr
->ia_valid
& ATTR_GID
)
1400 inode
->i_gid
= from_vfsgid(idmap
, i_user_ns(inode
),
1405 * inode_fsuid_set - initialize inode's i_uid field with callers fsuid
1406 * @inode: inode to initialize
1407 * @idmap: idmap of the mount the inode was found from
1409 * Initialize the i_uid field of @inode. If the inode was found/created via
1410 * an idmapped mount map the caller's fsuid according to @idmap.
1412 static inline void inode_fsuid_set(struct inode
*inode
,
1413 struct mnt_idmap
*idmap
)
1415 inode
->i_uid
= mapped_fsuid(idmap
, i_user_ns(inode
));
1419 * inode_fsgid_set - initialize inode's i_gid field with callers fsgid
1420 * @inode: inode to initialize
1421 * @idmap: idmap of the mount the inode was found from
1423 * Initialize the i_gid field of @inode. If the inode was found/created via
1424 * an idmapped mount map the caller's fsgid according to @idmap.
1426 static inline void inode_fsgid_set(struct inode
*inode
,
1427 struct mnt_idmap
*idmap
)
1429 inode
->i_gid
= mapped_fsgid(idmap
, i_user_ns(inode
));
1433 * fsuidgid_has_mapping() - check whether caller's fsuid/fsgid is mapped
1434 * @sb: the superblock we want a mapping in
1435 * @idmap: idmap of the relevant mount
1437 * Check whether the caller's fsuid and fsgid have a valid mapping in the
1438 * s_user_ns of the superblock @sb. If the caller is on an idmapped mount map
1439 * the caller's fsuid and fsgid according to the @idmap first.
1441 * Return: true if fsuid and fsgid is mapped, false if not.
1443 static inline bool fsuidgid_has_mapping(struct super_block
*sb
,
1444 struct mnt_idmap
*idmap
)
1446 struct user_namespace
*fs_userns
= sb
->s_user_ns
;
1450 kuid
= mapped_fsuid(idmap
, fs_userns
);
1451 if (!uid_valid(kuid
))
1453 kgid
= mapped_fsgid(idmap
, fs_userns
);
1454 if (!gid_valid(kgid
))
1456 return kuid_has_mapping(fs_userns
, kuid
) &&
1457 kgid_has_mapping(fs_userns
, kgid
);
1460 extern struct timespec64
current_time(struct inode
*inode
);
1463 * Snapshotting support.
1467 * These are internal functions, please use sb_start_{write,pagefault,intwrite}
1470 static inline void __sb_end_write(struct super_block
*sb
, int level
)
1472 percpu_up_read(sb
->s_writers
.rw_sem
+ level
-1);
1475 static inline void __sb_start_write(struct super_block
*sb
, int level
)
1477 percpu_down_read(sb
->s_writers
.rw_sem
+ level
- 1);
1480 static inline bool __sb_start_write_trylock(struct super_block
*sb
, int level
)
1482 return percpu_down_read_trylock(sb
->s_writers
.rw_sem
+ level
- 1);
1485 #define __sb_writers_acquired(sb, lev) \
1486 percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1487 #define __sb_writers_release(sb, lev) \
1488 percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1490 static inline bool sb_write_started(const struct super_block
*sb
)
1492 return lockdep_is_held_type(sb
->s_writers
.rw_sem
+ SB_FREEZE_WRITE
- 1, 1);
1496 * sb_end_write - drop write access to a superblock
1497 * @sb: the super we wrote to
1499 * Decrement number of writers to the filesystem. Wake up possible waiters
1500 * wanting to freeze the filesystem.
1502 static inline void sb_end_write(struct super_block
*sb
)
1504 __sb_end_write(sb
, SB_FREEZE_WRITE
);
1508 * sb_end_pagefault - drop write access to a superblock from a page fault
1509 * @sb: the super we wrote to
1511 * Decrement number of processes handling write page fault to the filesystem.
1512 * Wake up possible waiters wanting to freeze the filesystem.
1514 static inline void sb_end_pagefault(struct super_block
*sb
)
1516 __sb_end_write(sb
, SB_FREEZE_PAGEFAULT
);
1520 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1521 * @sb: the super we wrote to
1523 * Decrement fs-internal number of writers to the filesystem. Wake up possible
1524 * waiters wanting to freeze the filesystem.
1526 static inline void sb_end_intwrite(struct super_block
*sb
)
1528 __sb_end_write(sb
, SB_FREEZE_FS
);
1532 * sb_start_write - get write access to a superblock
1533 * @sb: the super we write to
1535 * When a process wants to write data or metadata to a file system (i.e. dirty
1536 * a page or an inode), it should embed the operation in a sb_start_write() -
1537 * sb_end_write() pair to get exclusion against file system freezing. This
1538 * function increments number of writers preventing freezing. If the file
1539 * system is already frozen, the function waits until the file system is
1542 * Since freeze protection behaves as a lock, users have to preserve
1543 * ordering of freeze protection and other filesystem locks. Generally,
1544 * freeze protection should be the outermost lock. In particular, we have:
1547 * -> i_mutex (write path, truncate, directory ops, ...)
1548 * -> s_umount (freeze_super, thaw_super)
1550 static inline void sb_start_write(struct super_block
*sb
)
1552 __sb_start_write(sb
, SB_FREEZE_WRITE
);
1555 static inline bool sb_start_write_trylock(struct super_block
*sb
)
1557 return __sb_start_write_trylock(sb
, SB_FREEZE_WRITE
);
1561 * sb_start_pagefault - get write access to a superblock from a page fault
1562 * @sb: the super we write to
1564 * When a process starts handling write page fault, it should embed the
1565 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1566 * exclusion against file system freezing. This is needed since the page fault
1567 * is going to dirty a page. This function increments number of running page
1568 * faults preventing freezing. If the file system is already frozen, the
1569 * function waits until the file system is thawed.
1571 * Since page fault freeze protection behaves as a lock, users have to preserve
1572 * ordering of freeze protection and other filesystem locks. It is advised to
1573 * put sb_start_pagefault() close to mmap_lock in lock ordering. Page fault
1574 * handling code implies lock dependency:
1577 * -> sb_start_pagefault
1579 static inline void sb_start_pagefault(struct super_block
*sb
)
1581 __sb_start_write(sb
, SB_FREEZE_PAGEFAULT
);
1585 * sb_start_intwrite - get write access to a superblock for internal fs purposes
1586 * @sb: the super we write to
1588 * This is the third level of protection against filesystem freezing. It is
1589 * free for use by a filesystem. The only requirement is that it must rank
1590 * below sb_start_pagefault.
1592 * For example filesystem can call sb_start_intwrite() when starting a
1593 * transaction which somewhat eases handling of freezing for internal sources
1594 * of filesystem changes (internal fs threads, discarding preallocation on file
1597 static inline void sb_start_intwrite(struct super_block
*sb
)
1599 __sb_start_write(sb
, SB_FREEZE_FS
);
1602 static inline bool sb_start_intwrite_trylock(struct super_block
*sb
)
1604 return __sb_start_write_trylock(sb
, SB_FREEZE_FS
);
1607 bool inode_owner_or_capable(struct mnt_idmap
*idmap
,
1608 const struct inode
*inode
);
1611 * VFS helper functions..
1613 int vfs_create(struct mnt_idmap
*, struct inode
*,
1614 struct dentry
*, umode_t
, bool);
1615 int vfs_mkdir(struct mnt_idmap
*, struct inode
*,
1616 struct dentry
*, umode_t
);
1617 int vfs_mknod(struct mnt_idmap
*, struct inode
*, struct dentry
*,
1619 int vfs_symlink(struct mnt_idmap
*, struct inode
*,
1620 struct dentry
*, const char *);
1621 int vfs_link(struct dentry
*, struct mnt_idmap
*, struct inode
*,
1622 struct dentry
*, struct inode
**);
1623 int vfs_rmdir(struct mnt_idmap
*, struct inode
*, struct dentry
*);
1624 int vfs_unlink(struct mnt_idmap
*, struct inode
*, struct dentry
*,
1628 * struct renamedata - contains all information required for renaming
1629 * @old_mnt_idmap: idmap of the old mount the inode was found from
1630 * @old_dir: parent of source
1631 * @old_dentry: source
1632 * @new_mnt_idmap: idmap of the new mount the inode was found from
1633 * @new_dir: parent of destination
1634 * @new_dentry: destination
1635 * @delegated_inode: returns an inode needing a delegation break
1636 * @flags: rename flags
1639 struct mnt_idmap
*old_mnt_idmap
;
1640 struct inode
*old_dir
;
1641 struct dentry
*old_dentry
;
1642 struct mnt_idmap
*new_mnt_idmap
;
1643 struct inode
*new_dir
;
1644 struct dentry
*new_dentry
;
1645 struct inode
**delegated_inode
;
1647 } __randomize_layout
;
1649 int vfs_rename(struct renamedata
*);
1651 static inline int vfs_whiteout(struct mnt_idmap
*idmap
,
1652 struct inode
*dir
, struct dentry
*dentry
)
1654 return vfs_mknod(idmap
, dir
, dentry
, S_IFCHR
| WHITEOUT_MODE
,
1658 struct file
*vfs_tmpfile_open(struct mnt_idmap
*idmap
,
1659 const struct path
*parentpath
,
1660 umode_t mode
, int open_flag
, const struct cred
*cred
);
1662 int vfs_mkobj(struct dentry
*, umode_t
,
1663 int (*f
)(struct dentry
*, umode_t
, void *),
1666 int vfs_fchown(struct file
*file
, uid_t user
, gid_t group
);
1667 int vfs_fchmod(struct file
*file
, umode_t mode
);
1668 int vfs_utimes(const struct path
*path
, struct timespec64
*times
);
1670 extern long vfs_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
);
1672 #ifdef CONFIG_COMPAT
1673 extern long compat_ptr_ioctl(struct file
*file
, unsigned int cmd
,
1676 #define compat_ptr_ioctl NULL
1680 * VFS file helper functions.
1682 void inode_init_owner(struct mnt_idmap
*idmap
, struct inode
*inode
,
1683 const struct inode
*dir
, umode_t mode
);
1684 extern bool may_open_dev(const struct path
*path
);
1685 umode_t
mode_strip_sgid(struct mnt_idmap
*idmap
,
1686 const struct inode
*dir
, umode_t mode
);
1689 * This is the "filldir" function type, used by readdir() to let
1690 * the kernel specify what kind of dirent layout it wants to have.
1691 * This allows the kernel to read directories into kernel space or
1692 * to have different dirent layouts depending on the binary type.
1693 * Return 'true' to keep going and 'false' if there are no more entries.
1696 typedef bool (*filldir_t
)(struct dir_context
*, const char *, int, loff_t
, u64
,
1699 struct dir_context
{
1705 * These flags let !MMU mmap() govern direct device mapping vs immediate
1706 * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1708 * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1709 * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1710 * NOMMU_MAP_READ: Can be mapped for reading
1711 * NOMMU_MAP_WRITE: Can be mapped for writing
1712 * NOMMU_MAP_EXEC: Can be mapped for execution
1714 #define NOMMU_MAP_COPY 0x00000001
1715 #define NOMMU_MAP_DIRECT 0x00000008
1716 #define NOMMU_MAP_READ VM_MAYREAD
1717 #define NOMMU_MAP_WRITE VM_MAYWRITE
1718 #define NOMMU_MAP_EXEC VM_MAYEXEC
1720 #define NOMMU_VMFLAGS \
1721 (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1724 * These flags control the behavior of the remap_file_range function pointer.
1725 * If it is called with len == 0 that means "remap to end of source file".
1726 * See Documentation/filesystems/vfs.rst for more details about this call.
1728 * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate)
1729 * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request
1731 #define REMAP_FILE_DEDUP (1 << 0)
1732 #define REMAP_FILE_CAN_SHORTEN (1 << 1)
1735 * These flags signal that the caller is ok with altering various aspects of
1736 * the behavior of the remap operation. The changes must be made by the
1737 * implementation; the vfs remap helper functions can take advantage of them.
1738 * Flags in this category exist to preserve the quirky behavior of the hoisted
1739 * btrfs clone/dedupe ioctls.
1741 #define REMAP_FILE_ADVISORY (REMAP_FILE_CAN_SHORTEN)
1744 * These flags control the behavior of vfs_copy_file_range().
1745 * They are not available to the user via syscall.
1747 * COPY_FILE_SPLICE: call splice direct instead of fs clone/copy ops
1749 #define COPY_FILE_SPLICE (1 << 0)
1752 struct io_uring_cmd
;
1754 struct file_operations
{
1755 struct module
*owner
;
1756 loff_t (*llseek
) (struct file
*, loff_t
, int);
1757 ssize_t (*read
) (struct file
*, char __user
*, size_t, loff_t
*);
1758 ssize_t (*write
) (struct file
*, const char __user
*, size_t, loff_t
*);
1759 ssize_t (*read_iter
) (struct kiocb
*, struct iov_iter
*);
1760 ssize_t (*write_iter
) (struct kiocb
*, struct iov_iter
*);
1761 int (*iopoll
)(struct kiocb
*kiocb
, struct io_comp_batch
*,
1762 unsigned int flags
);
1763 int (*iterate
) (struct file
*, struct dir_context
*);
1764 int (*iterate_shared
) (struct file
*, struct dir_context
*);
1765 __poll_t (*poll
) (struct file
*, struct poll_table_struct
*);
1766 long (*unlocked_ioctl
) (struct file
*, unsigned int, unsigned long);
1767 long (*compat_ioctl
) (struct file
*, unsigned int, unsigned long);
1768 int (*mmap
) (struct file
*, struct vm_area_struct
*);
1769 unsigned long mmap_supported_flags
;
1770 int (*open
) (struct inode
*, struct file
*);
1771 int (*flush
) (struct file
*, fl_owner_t id
);
1772 int (*release
) (struct inode
*, struct file
*);
1773 int (*fsync
) (struct file
*, loff_t
, loff_t
, int datasync
);
1774 int (*fasync
) (int, struct file
*, int);
1775 int (*lock
) (struct file
*, int, struct file_lock
*);
1776 ssize_t (*sendpage
) (struct file
*, struct page
*, int, size_t, loff_t
*, int);
1777 unsigned long (*get_unmapped_area
)(struct file
*, unsigned long, unsigned long, unsigned long, unsigned long);
1778 int (*check_flags
)(int);
1779 int (*flock
) (struct file
*, int, struct file_lock
*);
1780 ssize_t (*splice_write
)(struct pipe_inode_info
*, struct file
*, loff_t
*, size_t, unsigned int);
1781 ssize_t (*splice_read
)(struct file
*, loff_t
*, struct pipe_inode_info
*, size_t, unsigned int);
1782 int (*setlease
)(struct file
*, long, struct file_lock
**, void **);
1783 long (*fallocate
)(struct file
*file
, int mode
, loff_t offset
,
1785 void (*show_fdinfo
)(struct seq_file
*m
, struct file
*f
);
1787 unsigned (*mmap_capabilities
)(struct file
*);
1789 ssize_t (*copy_file_range
)(struct file
*, loff_t
, struct file
*,
1790 loff_t
, size_t, unsigned int);
1791 loff_t (*remap_file_range
)(struct file
*file_in
, loff_t pos_in
,
1792 struct file
*file_out
, loff_t pos_out
,
1793 loff_t len
, unsigned int remap_flags
);
1794 int (*fadvise
)(struct file
*, loff_t
, loff_t
, int);
1795 int (*uring_cmd
)(struct io_uring_cmd
*ioucmd
, unsigned int issue_flags
);
1796 int (*uring_cmd_iopoll
)(struct io_uring_cmd
*, struct io_comp_batch
*,
1797 unsigned int poll_flags
);
1798 } __randomize_layout
;
1800 struct inode_operations
{
1801 struct dentry
* (*lookup
) (struct inode
*,struct dentry
*, unsigned int);
1802 const char * (*get_link
) (struct dentry
*, struct inode
*, struct delayed_call
*);
1803 int (*permission
) (struct mnt_idmap
*, struct inode
*, int);
1804 struct posix_acl
* (*get_inode_acl
)(struct inode
*, int, bool);
1806 int (*readlink
) (struct dentry
*, char __user
*,int);
1808 int (*create
) (struct mnt_idmap
*, struct inode
*,struct dentry
*,
1810 int (*link
) (struct dentry
*,struct inode
*,struct dentry
*);
1811 int (*unlink
) (struct inode
*,struct dentry
*);
1812 int (*symlink
) (struct mnt_idmap
*, struct inode
*,struct dentry
*,
1814 int (*mkdir
) (struct mnt_idmap
*, struct inode
*,struct dentry
*,
1816 int (*rmdir
) (struct inode
*,struct dentry
*);
1817 int (*mknod
) (struct mnt_idmap
*, struct inode
*,struct dentry
*,
1819 int (*rename
) (struct mnt_idmap
*, struct inode
*, struct dentry
*,
1820 struct inode
*, struct dentry
*, unsigned int);
1821 int (*setattr
) (struct mnt_idmap
*, struct dentry
*, struct iattr
*);
1822 int (*getattr
) (struct mnt_idmap
*, const struct path
*,
1823 struct kstat
*, u32
, unsigned int);
1824 ssize_t (*listxattr
) (struct dentry
*, char *, size_t);
1825 int (*fiemap
)(struct inode
*, struct fiemap_extent_info
*, u64 start
,
1827 int (*update_time
)(struct inode
*, struct timespec64
*, int);
1828 int (*atomic_open
)(struct inode
*, struct dentry
*,
1829 struct file
*, unsigned open_flag
,
1830 umode_t create_mode
);
1831 int (*tmpfile
) (struct mnt_idmap
*, struct inode
*,
1832 struct file
*, umode_t
);
1833 struct posix_acl
*(*get_acl
)(struct mnt_idmap
*, struct dentry
*,
1835 int (*set_acl
)(struct mnt_idmap
*, struct dentry
*,
1836 struct posix_acl
*, int);
1837 int (*fileattr_set
)(struct mnt_idmap
*idmap
,
1838 struct dentry
*dentry
, struct fileattr
*fa
);
1839 int (*fileattr_get
)(struct dentry
*dentry
, struct fileattr
*fa
);
1840 } ____cacheline_aligned
;
1842 static inline ssize_t
call_read_iter(struct file
*file
, struct kiocb
*kio
,
1843 struct iov_iter
*iter
)
1845 return file
->f_op
->read_iter(kio
, iter
);
1848 static inline ssize_t
call_write_iter(struct file
*file
, struct kiocb
*kio
,
1849 struct iov_iter
*iter
)
1851 return file
->f_op
->write_iter(kio
, iter
);
1854 static inline int call_mmap(struct file
*file
, struct vm_area_struct
*vma
)
1856 return file
->f_op
->mmap(file
, vma
);
1859 extern ssize_t
vfs_read(struct file
*, char __user
*, size_t, loff_t
*);
1860 extern ssize_t
vfs_write(struct file
*, const char __user
*, size_t, loff_t
*);
1861 extern ssize_t
vfs_copy_file_range(struct file
*, loff_t
, struct file
*,
1862 loff_t
, size_t, unsigned int);
1863 extern ssize_t
generic_copy_file_range(struct file
*file_in
, loff_t pos_in
,
1864 struct file
*file_out
, loff_t pos_out
,
1865 size_t len
, unsigned int flags
);
1866 int __generic_remap_file_range_prep(struct file
*file_in
, loff_t pos_in
,
1867 struct file
*file_out
, loff_t pos_out
,
1868 loff_t
*len
, unsigned int remap_flags
,
1869 const struct iomap_ops
*dax_read_ops
);
1870 int generic_remap_file_range_prep(struct file
*file_in
, loff_t pos_in
,
1871 struct file
*file_out
, loff_t pos_out
,
1872 loff_t
*count
, unsigned int remap_flags
);
1873 extern loff_t
do_clone_file_range(struct file
*file_in
, loff_t pos_in
,
1874 struct file
*file_out
, loff_t pos_out
,
1875 loff_t len
, unsigned int remap_flags
);
1876 extern loff_t
vfs_clone_file_range(struct file
*file_in
, loff_t pos_in
,
1877 struct file
*file_out
, loff_t pos_out
,
1878 loff_t len
, unsigned int remap_flags
);
1879 extern int vfs_dedupe_file_range(struct file
*file
,
1880 struct file_dedupe_range
*same
);
1881 extern loff_t
vfs_dedupe_file_range_one(struct file
*src_file
, loff_t src_pos
,
1882 struct file
*dst_file
, loff_t dst_pos
,
1883 loff_t len
, unsigned int remap_flags
);
1886 struct super_operations
{
1887 struct inode
*(*alloc_inode
)(struct super_block
*sb
);
1888 void (*destroy_inode
)(struct inode
*);
1889 void (*free_inode
)(struct inode
*);
1891 void (*dirty_inode
) (struct inode
*, int flags
);
1892 int (*write_inode
) (struct inode
*, struct writeback_control
*wbc
);
1893 int (*drop_inode
) (struct inode
*);
1894 void (*evict_inode
) (struct inode
*);
1895 void (*put_super
) (struct super_block
*);
1896 int (*sync_fs
)(struct super_block
*sb
, int wait
);
1897 int (*freeze_super
) (struct super_block
*);
1898 int (*freeze_fs
) (struct super_block
*);
1899 int (*thaw_super
) (struct super_block
*);
1900 int (*unfreeze_fs
) (struct super_block
*);
1901 int (*statfs
) (struct dentry
*, struct kstatfs
*);
1902 int (*remount_fs
) (struct super_block
*, int *, char *);
1903 void (*umount_begin
) (struct super_block
*);
1905 int (*show_options
)(struct seq_file
*, struct dentry
*);
1906 int (*show_devname
)(struct seq_file
*, struct dentry
*);
1907 int (*show_path
)(struct seq_file
*, struct dentry
*);
1908 int (*show_stats
)(struct seq_file
*, struct dentry
*);
1910 ssize_t (*quota_read
)(struct super_block
*, int, char *, size_t, loff_t
);
1911 ssize_t (*quota_write
)(struct super_block
*, int, const char *, size_t, loff_t
);
1912 struct dquot
**(*get_dquots
)(struct inode
*);
1914 long (*nr_cached_objects
)(struct super_block
*,
1915 struct shrink_control
*);
1916 long (*free_cached_objects
)(struct super_block
*,
1917 struct shrink_control
*);
1921 * Inode flags - they have no relation to superblock flags now
1923 #define S_SYNC (1 << 0) /* Writes are synced at once */
1924 #define S_NOATIME (1 << 1) /* Do not update access times */
1925 #define S_APPEND (1 << 2) /* Append-only file */
1926 #define S_IMMUTABLE (1 << 3) /* Immutable file */
1927 #define S_DEAD (1 << 4) /* removed, but still open directory */
1928 #define S_NOQUOTA (1 << 5) /* Inode is not counted to quota */
1929 #define S_DIRSYNC (1 << 6) /* Directory modifications are synchronous */
1930 #define S_NOCMTIME (1 << 7) /* Do not update file c/mtime */
1931 #define S_SWAPFILE (1 << 8) /* Do not truncate: swapon got its bmaps */
1932 #define S_PRIVATE (1 << 9) /* Inode is fs-internal */
1933 #define S_IMA (1 << 10) /* Inode has an associated IMA struct */
1934 #define S_AUTOMOUNT (1 << 11) /* Automount/referral quasi-directory */
1935 #define S_NOSEC (1 << 12) /* no suid or xattr security attributes */
1936 #ifdef CONFIG_FS_DAX
1937 #define S_DAX (1 << 13) /* Direct Access, avoiding the page cache */
1939 #define S_DAX 0 /* Make all the DAX code disappear */
1941 #define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
1942 #define S_CASEFOLD (1 << 15) /* Casefolded file */
1943 #define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
1944 #define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
1947 * Note that nosuid etc flags are inode-specific: setting some file-system
1948 * flags just means all the inodes inherit those flags by default. It might be
1949 * possible to override it selectively if you really wanted to with some
1950 * ioctl() that is not currently implemented.
1952 * Exception: SB_RDONLY is always applied to the entire file system.
1954 * Unfortunately, it is possible to change a filesystems flags with it mounted
1955 * with files in use. This means that all of the inodes will not have their
1956 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1957 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1959 #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1961 static inline bool sb_rdonly(const struct super_block
*sb
) { return sb
->s_flags
& SB_RDONLY
; }
1962 #define IS_RDONLY(inode) sb_rdonly((inode)->i_sb)
1963 #define IS_SYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS) || \
1964 ((inode)->i_flags & S_SYNC))
1965 #define IS_DIRSYNC(inode) (__IS_FLG(inode, SB_SYNCHRONOUS|SB_DIRSYNC) || \
1966 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1967 #define IS_MANDLOCK(inode) __IS_FLG(inode, SB_MANDLOCK)
1968 #define IS_NOATIME(inode) __IS_FLG(inode, SB_RDONLY|SB_NOATIME)
1969 #define IS_I_VERSION(inode) __IS_FLG(inode, SB_I_VERSION)
1971 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1972 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1973 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1974 #define IS_POSIXACL(inode) __IS_FLG(inode, SB_POSIXACL)
1976 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1977 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1978 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1979 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1980 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1981 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1982 #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
1983 #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
1984 #define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED)
1985 #define IS_CASEFOLDED(inode) ((inode)->i_flags & S_CASEFOLD)
1986 #define IS_VERITY(inode) ((inode)->i_flags & S_VERITY)
1988 #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
1989 (inode)->i_rdev == WHITEOUT_DEV)
1991 static inline bool HAS_UNMAPPED_ID(struct mnt_idmap
*idmap
,
1992 struct inode
*inode
)
1994 return !vfsuid_valid(i_uid_into_vfsuid(idmap
, inode
)) ||
1995 !vfsgid_valid(i_gid_into_vfsgid(idmap
, inode
));
1998 static inline void init_sync_kiocb(struct kiocb
*kiocb
, struct file
*filp
)
2000 *kiocb
= (struct kiocb
) {
2002 .ki_flags
= filp
->f_iocb_flags
,
2003 .ki_ioprio
= get_current_ioprio(),
2007 static inline void kiocb_clone(struct kiocb
*kiocb
, struct kiocb
*kiocb_src
,
2010 *kiocb
= (struct kiocb
) {
2012 .ki_flags
= kiocb_src
->ki_flags
,
2013 .ki_ioprio
= kiocb_src
->ki_ioprio
,
2014 .ki_pos
= kiocb_src
->ki_pos
,
2019 * Inode state bits. Protected by inode->i_lock
2021 * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
2022 * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
2024 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
2025 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
2026 * various stages of removing an inode.
2028 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
2030 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
2031 * fdatasync() (unless I_DIRTY_DATASYNC is also set).
2032 * Timestamp updates are the usual cause.
2033 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
2034 * these changes separately from I_DIRTY_SYNC so that we
2035 * don't have to write inode on fdatasync() when only
2036 * e.g. the timestamps have changed.
2037 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
2038 * I_DIRTY_TIME The inode itself has dirty timestamps, and the
2039 * lazytime mount option is enabled. We keep track of this
2040 * separately from I_DIRTY_SYNC in order to implement
2041 * lazytime. This gets cleared if I_DIRTY_INODE
2042 * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. But
2043 * I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already
2044 * in place because writeback might already be in progress
2045 * and we don't want to lose the time update
2046 * I_NEW Serves as both a mutex and completion notification.
2047 * New inodes set I_NEW. If two processes both create
2048 * the same inode, one of them will release its inode and
2049 * wait for I_NEW to be released before returning.
2050 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
2051 * also cause waiting on I_NEW, without I_NEW actually
2052 * being set. find_inode() uses this to prevent returning
2053 * nearly-dead inodes.
2054 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
2055 * is zero. I_FREEING must be set when I_WILL_FREE is
2057 * I_FREEING Set when inode is about to be freed but still has dirty
2058 * pages or buffers attached or the inode itself is still
2060 * I_CLEAR Added by clear_inode(). In this state the inode is
2061 * clean and can be destroyed. Inode keeps I_FREEING.
2063 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
2064 * prohibited for many purposes. iget() must wait for
2065 * the inode to be completely released, then create it
2066 * anew. Other functions will just ignore such inodes,
2067 * if appropriate. I_NEW is used for waiting.
2069 * I_SYNC Writeback of inode is running. The bit is set during
2070 * data writeback, and cleared with a wakeup on the bit
2071 * address once it is done. The bit is also used to pin
2072 * the inode in memory for flusher thread.
2074 * I_REFERENCED Marks the inode as recently references on the LRU list.
2076 * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
2078 * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
2079 * synchronize competing switching instances and to tell
2080 * wb stat updates to grab the i_pages lock. See
2081 * inode_switch_wbs_work_fn() for details.
2083 * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
2084 * and work dirs among overlayfs mounts.
2086 * I_CREATING New object's inode in the middle of setting up.
2088 * I_DONTCACHE Evict inode as soon as it is not used anymore.
2090 * I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
2091 * Used to detect that mark_inode_dirty() should not move
2092 * inode between dirty lists.
2094 * I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
2096 * Q: What is the difference between I_WILL_FREE and I_FREEING?
2098 #define I_DIRTY_SYNC (1 << 0)
2099 #define I_DIRTY_DATASYNC (1 << 1)
2100 #define I_DIRTY_PAGES (1 << 2)
2102 #define I_NEW (1 << __I_NEW)
2103 #define I_WILL_FREE (1 << 4)
2104 #define I_FREEING (1 << 5)
2105 #define I_CLEAR (1 << 6)
2107 #define I_SYNC (1 << __I_SYNC)
2108 #define I_REFERENCED (1 << 8)
2109 #define __I_DIO_WAKEUP 9
2110 #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
2111 #define I_LINKABLE (1 << 10)
2112 #define I_DIRTY_TIME (1 << 11)
2113 #define I_WB_SWITCH (1 << 13)
2114 #define I_OVL_INUSE (1 << 14)
2115 #define I_CREATING (1 << 15)
2116 #define I_DONTCACHE (1 << 16)
2117 #define I_SYNC_QUEUED (1 << 17)
2118 #define I_PINNING_FSCACHE_WB (1 << 18)
2120 #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
2121 #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
2122 #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
2124 extern void __mark_inode_dirty(struct inode
*, int);
2125 static inline void mark_inode_dirty(struct inode
*inode
)
2127 __mark_inode_dirty(inode
, I_DIRTY
);
2130 static inline void mark_inode_dirty_sync(struct inode
*inode
)
2132 __mark_inode_dirty(inode
, I_DIRTY_SYNC
);
2136 * Returns true if the given inode itself only has dirty timestamps (its pages
2137 * may still be dirty) and isn't currently being allocated or freed.
2138 * Filesystems should call this if when writing an inode when lazytime is
2139 * enabled, they want to opportunistically write the timestamps of other inodes
2140 * located very nearby on-disk, e.g. in the same inode block. This returns true
2141 * if the given inode is in need of such an opportunistic update. Requires
2142 * i_lock, or at least later re-checking under i_lock.
2144 static inline bool inode_is_dirtytime_only(struct inode
*inode
)
2146 return (inode
->i_state
& (I_DIRTY_TIME
| I_NEW
|
2147 I_FREEING
| I_WILL_FREE
)) == I_DIRTY_TIME
;
2150 extern void inc_nlink(struct inode
*inode
);
2151 extern void drop_nlink(struct inode
*inode
);
2152 extern void clear_nlink(struct inode
*inode
);
2153 extern void set_nlink(struct inode
*inode
, unsigned int nlink
);
2155 static inline void inode_inc_link_count(struct inode
*inode
)
2158 mark_inode_dirty(inode
);
2161 static inline void inode_dec_link_count(struct inode
*inode
)
2164 mark_inode_dirty(inode
);
2167 enum file_time_flags
{
2174 extern bool atime_needs_update(const struct path
*, struct inode
*);
2175 extern void touch_atime(const struct path
*);
2176 int inode_update_time(struct inode
*inode
, struct timespec64
*time
, int flags
);
2178 static inline void file_accessed(struct file
*file
)
2180 if (!(file
->f_flags
& O_NOATIME
))
2181 touch_atime(&file
->f_path
);
2184 extern int file_modified(struct file
*file
);
2185 int kiocb_modified(struct kiocb
*iocb
);
2187 int sync_inode_metadata(struct inode
*inode
, int wait
);
2189 struct file_system_type
{
2192 #define FS_REQUIRES_DEV 1
2193 #define FS_BINARY_MOUNTDATA 2
2194 #define FS_HAS_SUBTYPE 4
2195 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2196 #define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
2197 #define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
2198 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2199 int (*init_fs_context
)(struct fs_context
*);
2200 const struct fs_parameter_spec
*parameters
;
2201 struct dentry
*(*mount
) (struct file_system_type
*, int,
2202 const char *, void *);
2203 void (*kill_sb
) (struct super_block
*);
2204 struct module
*owner
;
2205 struct file_system_type
* next
;
2206 struct hlist_head fs_supers
;
2208 struct lock_class_key s_lock_key
;
2209 struct lock_class_key s_umount_key
;
2210 struct lock_class_key s_vfs_rename_key
;
2211 struct lock_class_key s_writers_key
[SB_FREEZE_LEVELS
];
2213 struct lock_class_key i_lock_key
;
2214 struct lock_class_key i_mutex_key
;
2215 struct lock_class_key invalidate_lock_key
;
2216 struct lock_class_key i_mutex_dir_key
;
2219 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2221 extern struct dentry
*mount_bdev(struct file_system_type
*fs_type
,
2222 int flags
, const char *dev_name
, void *data
,
2223 int (*fill_super
)(struct super_block
*, void *, int));
2224 extern struct dentry
*mount_single(struct file_system_type
*fs_type
,
2225 int flags
, void *data
,
2226 int (*fill_super
)(struct super_block
*, void *, int));
2227 extern struct dentry
*mount_nodev(struct file_system_type
*fs_type
,
2228 int flags
, void *data
,
2229 int (*fill_super
)(struct super_block
*, void *, int));
2230 extern struct dentry
*mount_subtree(struct vfsmount
*mnt
, const char *path
);
2231 void retire_super(struct super_block
*sb
);
2232 void generic_shutdown_super(struct super_block
*sb
);
2233 void kill_block_super(struct super_block
*sb
);
2234 void kill_anon_super(struct super_block
*sb
);
2235 void kill_litter_super(struct super_block
*sb
);
2236 void deactivate_super(struct super_block
*sb
);
2237 void deactivate_locked_super(struct super_block
*sb
);
2238 int set_anon_super(struct super_block
*s
, void *data
);
2239 int set_anon_super_fc(struct super_block
*s
, struct fs_context
*fc
);
2240 int get_anon_bdev(dev_t
*);
2241 void free_anon_bdev(dev_t
);
2242 struct super_block
*sget_fc(struct fs_context
*fc
,
2243 int (*test
)(struct super_block
*, struct fs_context
*),
2244 int (*set
)(struct super_block
*, struct fs_context
*));
2245 struct super_block
*sget(struct file_system_type
*type
,
2246 int (*test
)(struct super_block
*,void *),
2247 int (*set
)(struct super_block
*,void *),
2248 int flags
, void *data
);
2250 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2251 #define fops_get(fops) \
2252 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2253 #define fops_put(fops) \
2254 do { if (fops) module_put((fops)->owner); } while(0)
2256 * This one is to be used *ONLY* from ->open() instances.
2257 * fops must be non-NULL, pinned down *and* module dependencies
2258 * should be sufficient to pin the caller down as well.
2260 #define replace_fops(f, fops) \
2262 struct file *__file = (f); \
2263 fops_put(__file->f_op); \
2264 BUG_ON(!(__file->f_op = (fops))); \
2267 extern int register_filesystem(struct file_system_type
*);
2268 extern int unregister_filesystem(struct file_system_type
*);
2269 extern int vfs_statfs(const struct path
*, struct kstatfs
*);
2270 extern int user_statfs(const char __user
*, struct kstatfs
*);
2271 extern int fd_statfs(int, struct kstatfs
*);
2272 extern int freeze_super(struct super_block
*super
);
2273 extern int thaw_super(struct super_block
*super
);
2274 extern __printf(2, 3)
2275 int super_setup_bdi_name(struct super_block
*sb
, char *fmt
, ...);
2276 extern int super_setup_bdi(struct super_block
*sb
);
2278 extern int current_umask(void);
2280 extern void ihold(struct inode
* inode
);
2281 extern void iput(struct inode
*);
2282 extern int generic_update_time(struct inode
*, struct timespec64
*, int);
2285 extern struct kobject
*fs_kobj
;
2287 #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2292 const char *name
; /* pointer to actual string */
2293 const __user
char *uptr
; /* original userland pointer */
2295 struct audit_names
*aname
;
2298 static_assert(offsetof(struct filename
, iname
) % sizeof(long) == 0);
2300 static inline struct mnt_idmap
*file_mnt_idmap(struct file
*file
)
2302 return mnt_idmap(file
->f_path
.mnt
);
2306 * is_idmapped_mnt - check whether a mount is mapped
2307 * @mnt: the mount to check
2309 * If @mnt has an non @nop_mnt_idmap attached to it then @mnt is mapped.
2311 * Return: true if mount is mapped, false if not.
2313 static inline bool is_idmapped_mnt(const struct vfsmount
*mnt
)
2315 return mnt_idmap(mnt
) != &nop_mnt_idmap
;
2318 extern long vfs_truncate(const struct path
*, loff_t
);
2319 int do_truncate(struct mnt_idmap
*, struct dentry
*, loff_t start
,
2320 unsigned int time_attrs
, struct file
*filp
);
2321 extern int vfs_fallocate(struct file
*file
, int mode
, loff_t offset
,
2323 extern long do_sys_open(int dfd
, const char __user
*filename
, int flags
,
2325 extern struct file
*file_open_name(struct filename
*, int, umode_t
);
2326 extern struct file
*filp_open(const char *, int, umode_t
);
2327 extern struct file
*file_open_root(const struct path
*,
2328 const char *, int, umode_t
);
2329 static inline struct file
*file_open_root_mnt(struct vfsmount
*mnt
,
2330 const char *name
, int flags
, umode_t mode
)
2332 return file_open_root(&(struct path
){.mnt
= mnt
, .dentry
= mnt
->mnt_root
},
2335 extern struct file
* dentry_open(const struct path
*, int, const struct cred
*);
2336 extern struct file
*dentry_create(const struct path
*path
, int flags
,
2337 umode_t mode
, const struct cred
*cred
);
2338 extern struct file
* open_with_fake_path(const struct path
*, int,
2339 struct inode
*, const struct cred
*);
2340 static inline struct file
*file_clone_open(struct file
*file
)
2342 return dentry_open(&file
->f_path
, file
->f_flags
, file
->f_cred
);
2344 extern int filp_close(struct file
*, fl_owner_t id
);
2346 extern struct filename
*getname_flags(const char __user
*, int, int *);
2347 extern struct filename
*getname_uflags(const char __user
*, int);
2348 extern struct filename
*getname(const char __user
*);
2349 extern struct filename
*getname_kernel(const char *);
2350 extern void putname(struct filename
*name
);
2352 extern int finish_open(struct file
*file
, struct dentry
*dentry
,
2353 int (*open
)(struct inode
*, struct file
*));
2354 extern int finish_no_open(struct file
*file
, struct dentry
*dentry
);
2356 /* Helper for the simple case when original dentry is used */
2357 static inline int finish_open_simple(struct file
*file
, int error
)
2362 return finish_open(file
, file
->f_path
.dentry
, NULL
);
2366 extern void __init
vfs_caches_init_early(void);
2367 extern void __init
vfs_caches_init(void);
2369 extern struct kmem_cache
*names_cachep
;
2371 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2372 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2374 extern struct super_block
*blockdev_superblock
;
2375 static inline bool sb_is_blkdev_sb(struct super_block
*sb
)
2377 return IS_ENABLED(CONFIG_BLOCK
) && sb
== blockdev_superblock
;
2380 void emergency_thaw_all(void);
2381 extern int sync_filesystem(struct super_block
*);
2382 extern const struct file_operations def_blk_fops
;
2383 extern const struct file_operations def_chr_fops
;
2386 #define CHRDEV_MAJOR_MAX 512
2387 /* Marks the bottom of the first segment of free char majors */
2388 #define CHRDEV_MAJOR_DYN_END 234
2389 /* Marks the top and bottom of the second segment of free char majors */
2390 #define CHRDEV_MAJOR_DYN_EXT_START 511
2391 #define CHRDEV_MAJOR_DYN_EXT_END 384
2393 extern int alloc_chrdev_region(dev_t
*, unsigned, unsigned, const char *);
2394 extern int register_chrdev_region(dev_t
, unsigned, const char *);
2395 extern int __register_chrdev(unsigned int major
, unsigned int baseminor
,
2396 unsigned int count
, const char *name
,
2397 const struct file_operations
*fops
);
2398 extern void __unregister_chrdev(unsigned int major
, unsigned int baseminor
,
2399 unsigned int count
, const char *name
);
2400 extern void unregister_chrdev_region(dev_t
, unsigned);
2401 extern void chrdev_show(struct seq_file
*,off_t
);
2403 static inline int register_chrdev(unsigned int major
, const char *name
,
2404 const struct file_operations
*fops
)
2406 return __register_chrdev(major
, 0, 256, name
, fops
);
2409 static inline void unregister_chrdev(unsigned int major
, const char *name
)
2411 __unregister_chrdev(major
, 0, 256, name
);
2414 extern void init_special_inode(struct inode
*, umode_t
, dev_t
);
2416 /* Invalid inode operations -- fs/bad_inode.c */
2417 extern void make_bad_inode(struct inode
*);
2418 extern bool is_bad_inode(struct inode
*);
2420 extern int __must_check
file_fdatawait_range(struct file
*file
, loff_t lstart
,
2422 extern int __must_check
file_check_and_advance_wb_err(struct file
*file
);
2423 extern int __must_check
file_write_and_wait_range(struct file
*file
,
2424 loff_t start
, loff_t end
);
2426 static inline int file_write_and_wait(struct file
*file
)
2428 return file_write_and_wait_range(file
, 0, LLONG_MAX
);
2431 extern int vfs_fsync_range(struct file
*file
, loff_t start
, loff_t end
,
2433 extern int vfs_fsync(struct file
*file
, int datasync
);
2435 extern int sync_file_range(struct file
*file
, loff_t offset
, loff_t nbytes
,
2436 unsigned int flags
);
2438 static inline bool iocb_is_dsync(const struct kiocb
*iocb
)
2440 return (iocb
->ki_flags
& IOCB_DSYNC
) ||
2441 IS_SYNC(iocb
->ki_filp
->f_mapping
->host
);
2445 * Sync the bytes written if this was a synchronous write. Expect ki_pos
2446 * to already be updated for the write, and will return either the amount
2447 * of bytes passed in, or an error if syncing the file failed.
2449 static inline ssize_t
generic_write_sync(struct kiocb
*iocb
, ssize_t count
)
2451 if (iocb_is_dsync(iocb
)) {
2452 int ret
= vfs_fsync_range(iocb
->ki_filp
,
2453 iocb
->ki_pos
- count
, iocb
->ki_pos
- 1,
2454 (iocb
->ki_flags
& IOCB_SYNC
) ? 0 : 1);
2462 extern void emergency_sync(void);
2463 extern void emergency_remount(void);
2466 extern int bmap(struct inode
*inode
, sector_t
*block
);
2468 static inline int bmap(struct inode
*inode
, sector_t
*block
)
2474 int notify_change(struct mnt_idmap
*, struct dentry
*,
2475 struct iattr
*, struct inode
**);
2476 int inode_permission(struct mnt_idmap
*, struct inode
*, int);
2477 int generic_permission(struct mnt_idmap
*, struct inode
*, int);
2478 static inline int file_permission(struct file
*file
, int mask
)
2480 return inode_permission(file_mnt_idmap(file
),
2481 file_inode(file
), mask
);
2483 static inline int path_permission(const struct path
*path
, int mask
)
2485 return inode_permission(mnt_idmap(path
->mnt
),
2486 d_inode(path
->dentry
), mask
);
2488 int __check_sticky(struct mnt_idmap
*idmap
, struct inode
*dir
,
2489 struct inode
*inode
);
2491 static inline bool execute_ok(struct inode
*inode
)
2493 return (inode
->i_mode
& S_IXUGO
) || S_ISDIR(inode
->i_mode
);
2496 static inline bool inode_wrong_type(const struct inode
*inode
, umode_t mode
)
2498 return (inode
->i_mode
^ mode
) & S_IFMT
;
2501 static inline void file_start_write(struct file
*file
)
2503 if (!S_ISREG(file_inode(file
)->i_mode
))
2505 sb_start_write(file_inode(file
)->i_sb
);
2508 static inline bool file_start_write_trylock(struct file
*file
)
2510 if (!S_ISREG(file_inode(file
)->i_mode
))
2512 return sb_start_write_trylock(file_inode(file
)->i_sb
);
2515 static inline void file_end_write(struct file
*file
)
2517 if (!S_ISREG(file_inode(file
)->i_mode
))
2519 __sb_end_write(file_inode(file
)->i_sb
, SB_FREEZE_WRITE
);
2523 * This is used for regular files where some users -- especially the
2524 * currently executed binary in a process, previously handled via
2525 * VM_DENYWRITE -- cannot handle concurrent write (and maybe mmap
2526 * read-write shared) accesses.
2528 * get_write_access() gets write permission for a file.
2529 * put_write_access() releases this write permission.
2530 * deny_write_access() denies write access to a file.
2531 * allow_write_access() re-enables write access to a file.
2533 * The i_writecount field of an inode can have the following values:
2534 * 0: no write access, no denied write access
2535 * < 0: (-i_writecount) users that denied write access to the file.
2536 * > 0: (i_writecount) users that have write access to the file.
2538 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2539 * except for the cases where we don't hold i_writecount yet. Then we need to
2540 * use {get,deny}_write_access() - these functions check the sign and refuse
2541 * to do the change if sign is wrong.
2543 static inline int get_write_access(struct inode
*inode
)
2545 return atomic_inc_unless_negative(&inode
->i_writecount
) ? 0 : -ETXTBSY
;
2547 static inline int deny_write_access(struct file
*file
)
2549 struct inode
*inode
= file_inode(file
);
2550 return atomic_dec_unless_positive(&inode
->i_writecount
) ? 0 : -ETXTBSY
;
2552 static inline void put_write_access(struct inode
* inode
)
2554 atomic_dec(&inode
->i_writecount
);
2556 static inline void allow_write_access(struct file
*file
)
2559 atomic_inc(&file_inode(file
)->i_writecount
);
2561 static inline bool inode_is_open_for_write(const struct inode
*inode
)
2563 return atomic_read(&inode
->i_writecount
) > 0;
2566 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
2567 static inline void i_readcount_dec(struct inode
*inode
)
2569 BUG_ON(!atomic_read(&inode
->i_readcount
));
2570 atomic_dec(&inode
->i_readcount
);
2572 static inline void i_readcount_inc(struct inode
*inode
)
2574 atomic_inc(&inode
->i_readcount
);
2577 static inline void i_readcount_dec(struct inode
*inode
)
2581 static inline void i_readcount_inc(struct inode
*inode
)
2586 extern int do_pipe_flags(int *, int);
2588 extern ssize_t
kernel_read(struct file
*, void *, size_t, loff_t
*);
2589 ssize_t
__kernel_read(struct file
*file
, void *buf
, size_t count
, loff_t
*pos
);
2590 extern ssize_t
kernel_write(struct file
*, const void *, size_t, loff_t
*);
2591 extern ssize_t
__kernel_write(struct file
*, const void *, size_t, loff_t
*);
2592 extern struct file
* open_exec(const char *);
2594 /* fs/dcache.c -- generic fs support functions */
2595 extern bool is_subdir(struct dentry
*, struct dentry
*);
2596 extern bool path_is_under(const struct path
*, const struct path
*);
2598 extern char *file_path(struct file
*, char *, int);
2600 #include <linux/err.h>
2602 /* needed for stackable file system support */
2603 extern loff_t
default_llseek(struct file
*file
, loff_t offset
, int whence
);
2605 extern loff_t
vfs_llseek(struct file
*file
, loff_t offset
, int whence
);
2607 extern int inode_init_always(struct super_block
*, struct inode
*);
2608 extern void inode_init_once(struct inode
*);
2609 extern void address_space_init_once(struct address_space
*mapping
);
2610 extern struct inode
* igrab(struct inode
*);
2611 extern ino_t
iunique(struct super_block
*, ino_t
);
2612 extern int inode_needs_sync(struct inode
*inode
);
2613 extern int generic_delete_inode(struct inode
*inode
);
2614 static inline int generic_drop_inode(struct inode
*inode
)
2616 return !inode
->i_nlink
|| inode_unhashed(inode
);
2618 extern void d_mark_dontcache(struct inode
*inode
);
2620 extern struct inode
*ilookup5_nowait(struct super_block
*sb
,
2621 unsigned long hashval
, int (*test
)(struct inode
*, void *),
2623 extern struct inode
*ilookup5(struct super_block
*sb
, unsigned long hashval
,
2624 int (*test
)(struct inode
*, void *), void *data
);
2625 extern struct inode
*ilookup(struct super_block
*sb
, unsigned long ino
);
2627 extern struct inode
*inode_insert5(struct inode
*inode
, unsigned long hashval
,
2628 int (*test
)(struct inode
*, void *),
2629 int (*set
)(struct inode
*, void *),
2631 extern struct inode
* iget5_locked(struct super_block
*, unsigned long, int (*test
)(struct inode
*, void *), int (*set
)(struct inode
*, void *), void *);
2632 extern struct inode
* iget_locked(struct super_block
*, unsigned long);
2633 extern struct inode
*find_inode_nowait(struct super_block
*,
2635 int (*match
)(struct inode
*,
2636 unsigned long, void *),
2638 extern struct inode
*find_inode_rcu(struct super_block
*, unsigned long,
2639 int (*)(struct inode
*, void *), void *);
2640 extern struct inode
*find_inode_by_ino_rcu(struct super_block
*, unsigned long);
2641 extern int insert_inode_locked4(struct inode
*, unsigned long, int (*test
)(struct inode
*, void *), void *);
2642 extern int insert_inode_locked(struct inode
*);
2643 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2644 extern void lockdep_annotate_inode_mutex_key(struct inode
*inode
);
2646 static inline void lockdep_annotate_inode_mutex_key(struct inode
*inode
) { };
2648 extern void unlock_new_inode(struct inode
*);
2649 extern void discard_new_inode(struct inode
*);
2650 extern unsigned int get_next_ino(void);
2651 extern void evict_inodes(struct super_block
*sb
);
2652 void dump_mapping(const struct address_space
*);
2655 * Userspace may rely on the the inode number being non-zero. For example, glibc
2656 * simply ignores files with zero i_ino in unlink() and other places.
2658 * As an additional complication, if userspace was compiled with
2659 * _FILE_OFFSET_BITS=32 on a 64-bit kernel we'll only end up reading out the
2660 * lower 32 bits, so we need to check that those aren't zero explicitly. With
2661 * _FILE_OFFSET_BITS=64, this may cause some harmless false-negatives, but
2662 * better safe than sorry.
2664 static inline bool is_zero_ino(ino_t ino
)
2666 return (u32
)ino
== 0;
2669 extern void __iget(struct inode
* inode
);
2670 extern void iget_failed(struct inode
*);
2671 extern void clear_inode(struct inode
*);
2672 extern void __destroy_inode(struct inode
*);
2673 extern struct inode
*new_inode_pseudo(struct super_block
*sb
);
2674 extern struct inode
*new_inode(struct super_block
*sb
);
2675 extern void free_inode_nonrcu(struct inode
*inode
);
2676 extern int setattr_should_drop_suidgid(struct mnt_idmap
*, struct inode
*);
2677 extern int file_remove_privs(struct file
*);
2680 * This must be used for allocating filesystems specific inodes to set
2681 * up the inode reclaim context correctly.
2683 static inline void *
2684 alloc_inode_sb(struct super_block
*sb
, struct kmem_cache
*cache
, gfp_t gfp
)
2686 return kmem_cache_alloc_lru(cache
, &sb
->s_inode_lru
, gfp
);
2689 extern void __insert_inode_hash(struct inode
*, unsigned long hashval
);
2690 static inline void insert_inode_hash(struct inode
*inode
)
2692 __insert_inode_hash(inode
, inode
->i_ino
);
2695 extern void __remove_inode_hash(struct inode
*);
2696 static inline void remove_inode_hash(struct inode
*inode
)
2698 if (!inode_unhashed(inode
) && !hlist_fake(&inode
->i_hash
))
2699 __remove_inode_hash(inode
);
2702 extern void inode_sb_list_add(struct inode
*inode
);
2703 extern void inode_add_lru(struct inode
*inode
);
2705 extern int sb_set_blocksize(struct super_block
*, int);
2706 extern int sb_min_blocksize(struct super_block
*, int);
2708 extern int generic_file_mmap(struct file
*, struct vm_area_struct
*);
2709 extern int generic_file_readonly_mmap(struct file
*, struct vm_area_struct
*);
2710 extern ssize_t
generic_write_checks(struct kiocb
*, struct iov_iter
*);
2711 int generic_write_checks_count(struct kiocb
*iocb
, loff_t
*count
);
2712 extern int generic_write_check_limits(struct file
*file
, loff_t pos
,
2714 extern int generic_file_rw_checks(struct file
*file_in
, struct file
*file_out
);
2715 ssize_t
filemap_read(struct kiocb
*iocb
, struct iov_iter
*to
,
2716 ssize_t already_read
);
2717 extern ssize_t
generic_file_read_iter(struct kiocb
*, struct iov_iter
*);
2718 extern ssize_t
__generic_file_write_iter(struct kiocb
*, struct iov_iter
*);
2719 extern ssize_t
generic_file_write_iter(struct kiocb
*, struct iov_iter
*);
2720 extern ssize_t
generic_file_direct_write(struct kiocb
*, struct iov_iter
*);
2721 ssize_t
generic_perform_write(struct kiocb
*, struct iov_iter
*);
2723 ssize_t
vfs_iter_read(struct file
*file
, struct iov_iter
*iter
, loff_t
*ppos
,
2725 ssize_t
vfs_iter_write(struct file
*file
, struct iov_iter
*iter
, loff_t
*ppos
,
2727 ssize_t
vfs_iocb_iter_read(struct file
*file
, struct kiocb
*iocb
,
2728 struct iov_iter
*iter
);
2729 ssize_t
vfs_iocb_iter_write(struct file
*file
, struct kiocb
*iocb
,
2730 struct iov_iter
*iter
);
2733 ssize_t
filemap_splice_read(struct file
*in
, loff_t
*ppos
,
2734 struct pipe_inode_info
*pipe
,
2735 size_t len
, unsigned int flags
);
2736 ssize_t
direct_splice_read(struct file
*in
, loff_t
*ppos
,
2737 struct pipe_inode_info
*pipe
,
2738 size_t len
, unsigned int flags
);
2739 extern ssize_t
generic_file_splice_read(struct file
*, loff_t
*,
2740 struct pipe_inode_info
*, size_t, unsigned int);
2741 extern ssize_t
iter_file_splice_write(struct pipe_inode_info
*,
2742 struct file
*, loff_t
*, size_t, unsigned int);
2743 extern ssize_t
generic_splice_sendpage(struct pipe_inode_info
*pipe
,
2744 struct file
*out
, loff_t
*, size_t len
, unsigned int flags
);
2745 extern long do_splice_direct(struct file
*in
, loff_t
*ppos
, struct file
*out
,
2746 loff_t
*opos
, size_t len
, unsigned int flags
);
2750 file_ra_state_init(struct file_ra_state
*ra
, struct address_space
*mapping
);
2751 extern loff_t
noop_llseek(struct file
*file
, loff_t offset
, int whence
);
2752 #define no_llseek NULL
2753 extern loff_t
vfs_setpos(struct file
*file
, loff_t offset
, loff_t maxsize
);
2754 extern loff_t
generic_file_llseek(struct file
*file
, loff_t offset
, int whence
);
2755 extern loff_t
generic_file_llseek_size(struct file
*file
, loff_t offset
,
2756 int whence
, loff_t maxsize
, loff_t eof
);
2757 extern loff_t
fixed_size_llseek(struct file
*file
, loff_t offset
,
2758 int whence
, loff_t size
);
2759 extern loff_t
no_seek_end_llseek_size(struct file
*, loff_t
, int, loff_t
);
2760 extern loff_t
no_seek_end_llseek(struct file
*, loff_t
, int);
2761 int rw_verify_area(int, struct file
*, const loff_t
*, size_t);
2762 extern int generic_file_open(struct inode
* inode
, struct file
* filp
);
2763 extern int nonseekable_open(struct inode
* inode
, struct file
* filp
);
2764 extern int stream_open(struct inode
* inode
, struct file
* filp
);
2767 typedef void (dio_submit_t
)(struct bio
*bio
, struct inode
*inode
,
2768 loff_t file_offset
);
2771 /* need locking between buffered and direct access */
2774 /* filesystem does not support filling holes */
2775 DIO_SKIP_HOLES
= 0x02,
2778 ssize_t
__blockdev_direct_IO(struct kiocb
*iocb
, struct inode
*inode
,
2779 struct block_device
*bdev
, struct iov_iter
*iter
,
2780 get_block_t get_block
,
2781 dio_iodone_t end_io
, dio_submit_t submit_io
,
2784 static inline ssize_t
blockdev_direct_IO(struct kiocb
*iocb
,
2785 struct inode
*inode
,
2786 struct iov_iter
*iter
,
2787 get_block_t get_block
)
2789 return __blockdev_direct_IO(iocb
, inode
, inode
->i_sb
->s_bdev
, iter
,
2790 get_block
, NULL
, NULL
, DIO_LOCKING
| DIO_SKIP_HOLES
);
2794 void inode_dio_wait(struct inode
*inode
);
2797 * inode_dio_begin - signal start of a direct I/O requests
2798 * @inode: inode the direct I/O happens on
2800 * This is called once we've finished processing a direct I/O request,
2801 * and is used to wake up callers waiting for direct I/O to be quiesced.
2803 static inline void inode_dio_begin(struct inode
*inode
)
2805 atomic_inc(&inode
->i_dio_count
);
2809 * inode_dio_end - signal finish of a direct I/O requests
2810 * @inode: inode the direct I/O happens on
2812 * This is called once we've finished processing a direct I/O request,
2813 * and is used to wake up callers waiting for direct I/O to be quiesced.
2815 static inline void inode_dio_end(struct inode
*inode
)
2817 if (atomic_dec_and_test(&inode
->i_dio_count
))
2818 wake_up_bit(&inode
->i_state
, __I_DIO_WAKEUP
);
2822 * Warn about a page cache invalidation failure diring a direct I/O write.
2824 void dio_warn_stale_pagecache(struct file
*filp
);
2826 extern void inode_set_flags(struct inode
*inode
, unsigned int flags
,
2829 extern const struct file_operations generic_ro_fops
;
2831 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2833 extern int readlink_copy(char __user
*, int, const char *);
2834 extern int page_readlink(struct dentry
*, char __user
*, int);
2835 extern const char *page_get_link(struct dentry
*, struct inode
*,
2836 struct delayed_call
*);
2837 extern void page_put_link(void *);
2838 extern int page_symlink(struct inode
*inode
, const char *symname
, int len
);
2839 extern const struct inode_operations page_symlink_inode_operations
;
2840 extern void kfree_link(void *);
2841 void generic_fillattr(struct mnt_idmap
*, struct inode
*, struct kstat
*);
2842 void generic_fill_statx_attr(struct inode
*inode
, struct kstat
*stat
);
2843 extern int vfs_getattr_nosec(const struct path
*, struct kstat
*, u32
, unsigned int);
2844 extern int vfs_getattr(const struct path
*, struct kstat
*, u32
, unsigned int);
2845 void __inode_add_bytes(struct inode
*inode
, loff_t bytes
);
2846 void inode_add_bytes(struct inode
*inode
, loff_t bytes
);
2847 void __inode_sub_bytes(struct inode
*inode
, loff_t bytes
);
2848 void inode_sub_bytes(struct inode
*inode
, loff_t bytes
);
2849 static inline loff_t
__inode_get_bytes(struct inode
*inode
)
2851 return (((loff_t
)inode
->i_blocks
) << 9) + inode
->i_bytes
;
2853 loff_t
inode_get_bytes(struct inode
*inode
);
2854 void inode_set_bytes(struct inode
*inode
, loff_t bytes
);
2855 const char *simple_get_link(struct dentry
*, struct inode
*,
2856 struct delayed_call
*);
2857 extern const struct inode_operations simple_symlink_inode_operations
;
2859 extern int iterate_dir(struct file
*, struct dir_context
*);
2861 int vfs_fstatat(int dfd
, const char __user
*filename
, struct kstat
*stat
,
2863 int vfs_fstat(int fd
, struct kstat
*stat
);
2865 static inline int vfs_stat(const char __user
*filename
, struct kstat
*stat
)
2867 return vfs_fstatat(AT_FDCWD
, filename
, stat
, 0);
2869 static inline int vfs_lstat(const char __user
*name
, struct kstat
*stat
)
2871 return vfs_fstatat(AT_FDCWD
, name
, stat
, AT_SYMLINK_NOFOLLOW
);
2874 extern const char *vfs_get_link(struct dentry
*, struct delayed_call
*);
2875 extern int vfs_readlink(struct dentry
*, char __user
*, int);
2877 extern struct file_system_type
*get_filesystem(struct file_system_type
*fs
);
2878 extern void put_filesystem(struct file_system_type
*fs
);
2879 extern struct file_system_type
*get_fs_type(const char *name
);
2880 extern struct super_block
*get_super(struct block_device
*);
2881 extern struct super_block
*get_active_super(struct block_device
*bdev
);
2882 extern void drop_super(struct super_block
*sb
);
2883 extern void drop_super_exclusive(struct super_block
*sb
);
2884 extern void iterate_supers(void (*)(struct super_block
*, void *), void *);
2885 extern void iterate_supers_type(struct file_system_type
*,
2886 void (*)(struct super_block
*, void *), void *);
2888 extern int dcache_dir_open(struct inode
*, struct file
*);
2889 extern int dcache_dir_close(struct inode
*, struct file
*);
2890 extern loff_t
dcache_dir_lseek(struct file
*, loff_t
, int);
2891 extern int dcache_readdir(struct file
*, struct dir_context
*);
2892 extern int simple_setattr(struct mnt_idmap
*, struct dentry
*,
2894 extern int simple_getattr(struct mnt_idmap
*, const struct path
*,
2895 struct kstat
*, u32
, unsigned int);
2896 extern int simple_statfs(struct dentry
*, struct kstatfs
*);
2897 extern int simple_open(struct inode
*inode
, struct file
*file
);
2898 extern int simple_link(struct dentry
*, struct inode
*, struct dentry
*);
2899 extern int simple_unlink(struct inode
*, struct dentry
*);
2900 extern int simple_rmdir(struct inode
*, struct dentry
*);
2901 extern int simple_rename_exchange(struct inode
*old_dir
, struct dentry
*old_dentry
,
2902 struct inode
*new_dir
, struct dentry
*new_dentry
);
2903 extern int simple_rename(struct mnt_idmap
*, struct inode
*,
2904 struct dentry
*, struct inode
*, struct dentry
*,
2906 extern void simple_recursive_removal(struct dentry
*,
2907 void (*callback
)(struct dentry
*));
2908 extern int noop_fsync(struct file
*, loff_t
, loff_t
, int);
2909 extern ssize_t
noop_direct_IO(struct kiocb
*iocb
, struct iov_iter
*iter
);
2910 extern int simple_empty(struct dentry
*);
2911 extern int simple_write_begin(struct file
*file
, struct address_space
*mapping
,
2912 loff_t pos
, unsigned len
,
2913 struct page
**pagep
, void **fsdata
);
2914 extern const struct address_space_operations ram_aops
;
2915 extern int always_delete_dentry(const struct dentry
*);
2916 extern struct inode
*alloc_anon_inode(struct super_block
*);
2917 extern int simple_nosetlease(struct file
*, long, struct file_lock
**, void **);
2918 extern const struct dentry_operations simple_dentry_operations
;
2920 extern struct dentry
*simple_lookup(struct inode
*, struct dentry
*, unsigned int flags
);
2921 extern ssize_t
generic_read_dir(struct file
*, char __user
*, size_t, loff_t
*);
2922 extern const struct file_operations simple_dir_operations
;
2923 extern const struct inode_operations simple_dir_inode_operations
;
2924 extern void make_empty_dir_inode(struct inode
*inode
);
2925 extern bool is_empty_dir_inode(struct inode
*inode
);
2926 struct tree_descr
{ const char *name
; const struct file_operations
*ops
; int mode
; };
2927 struct dentry
*d_alloc_name(struct dentry
*, const char *);
2928 extern int simple_fill_super(struct super_block
*, unsigned long,
2929 const struct tree_descr
*);
2930 extern int simple_pin_fs(struct file_system_type
*, struct vfsmount
**mount
, int *count
);
2931 extern void simple_release_fs(struct vfsmount
**mount
, int *count
);
2933 extern ssize_t
simple_read_from_buffer(void __user
*to
, size_t count
,
2934 loff_t
*ppos
, const void *from
, size_t available
);
2935 extern ssize_t
simple_write_to_buffer(void *to
, size_t available
, loff_t
*ppos
,
2936 const void __user
*from
, size_t count
);
2938 extern int __generic_file_fsync(struct file
*, loff_t
, loff_t
, int);
2939 extern int generic_file_fsync(struct file
*, loff_t
, loff_t
, int);
2941 extern int generic_check_addressable(unsigned, u64
);
2943 extern void generic_set_encrypted_ci_d_ops(struct dentry
*dentry
);
2945 int may_setattr(struct mnt_idmap
*idmap
, struct inode
*inode
,
2946 unsigned int ia_valid
);
2947 int setattr_prepare(struct mnt_idmap
*, struct dentry
*, struct iattr
*);
2948 extern int inode_newsize_ok(const struct inode
*, loff_t offset
);
2949 void setattr_copy(struct mnt_idmap
*, struct inode
*inode
,
2950 const struct iattr
*attr
);
2952 extern int file_update_time(struct file
*file
);
2954 static inline bool vma_is_dax(const struct vm_area_struct
*vma
)
2956 return vma
->vm_file
&& IS_DAX(vma
->vm_file
->f_mapping
->host
);
2959 static inline bool vma_is_fsdax(struct vm_area_struct
*vma
)
2961 struct inode
*inode
;
2963 if (!IS_ENABLED(CONFIG_FS_DAX
) || !vma
->vm_file
)
2965 if (!vma_is_dax(vma
))
2967 inode
= file_inode(vma
->vm_file
);
2968 if (S_ISCHR(inode
->i_mode
))
2969 return false; /* device-dax */
2973 static inline int iocb_flags(struct file
*file
)
2976 if (file
->f_flags
& O_APPEND
)
2978 if (file
->f_flags
& O_DIRECT
)
2980 if (file
->f_flags
& O_DSYNC
)
2982 if (file
->f_flags
& __O_SYNC
)
2987 static inline int kiocb_set_rw_flags(struct kiocb
*ki
, rwf_t flags
)
2989 int kiocb_flags
= 0;
2991 /* make sure there's no overlap between RWF and private IOCB flags */
2992 BUILD_BUG_ON((__force
int) RWF_SUPPORTED
& IOCB_EVENTFD
);
2996 if (unlikely(flags
& ~RWF_SUPPORTED
))
2999 if (flags
& RWF_NOWAIT
) {
3000 if (!(ki
->ki_filp
->f_mode
& FMODE_NOWAIT
))
3002 kiocb_flags
|= IOCB_NOIO
;
3004 kiocb_flags
|= (__force
int) (flags
& RWF_SUPPORTED
);
3005 if (flags
& RWF_SYNC
)
3006 kiocb_flags
|= IOCB_DSYNC
;
3008 ki
->ki_flags
|= kiocb_flags
;
3012 static inline ino_t
parent_ino(struct dentry
*dentry
)
3017 * Don't strictly need d_lock here? If the parent ino could change
3018 * then surely we'd have a deeper race in the caller?
3020 spin_lock(&dentry
->d_lock
);
3021 res
= dentry
->d_parent
->d_inode
->i_ino
;
3022 spin_unlock(&dentry
->d_lock
);
3026 /* Transaction based IO helpers */
3029 * An argresp is stored in an allocated page and holds the
3030 * size of the argument or response, along with its content
3032 struct simple_transaction_argresp
{
3037 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3039 char *simple_transaction_get(struct file
*file
, const char __user
*buf
,
3041 ssize_t
simple_transaction_read(struct file
*file
, char __user
*buf
,
3042 size_t size
, loff_t
*pos
);
3043 int simple_transaction_release(struct inode
*inode
, struct file
*file
);
3045 void simple_transaction_set(struct file
*file
, size_t n
);
3048 * simple attribute files
3050 * These attributes behave similar to those in sysfs:
3052 * Writing to an attribute immediately sets a value, an open file can be
3053 * written to multiple times.
3055 * Reading from an attribute creates a buffer from the value that might get
3056 * read with multiple read calls. When the attribute has been read
3057 * completely, no further read calls are possible until the file is opened
3060 * All attributes contain a text representation of a numeric value
3061 * that are accessed with the get() and set() functions.
3063 #define DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, __is_signed) \
3064 static int __fops ## _open(struct inode *inode, struct file *file) \
3066 __simple_attr_check_format(__fmt, 0ull); \
3067 return simple_attr_open(inode, file, __get, __set, __fmt); \
3069 static const struct file_operations __fops = { \
3070 .owner = THIS_MODULE, \
3071 .open = __fops ## _open, \
3072 .release = simple_attr_release, \
3073 .read = simple_attr_read, \
3074 .write = (__is_signed) ? simple_attr_write_signed : simple_attr_write, \
3075 .llseek = generic_file_llseek, \
3078 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3079 DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, false)
3081 #define DEFINE_SIMPLE_ATTRIBUTE_SIGNED(__fops, __get, __set, __fmt) \
3082 DEFINE_SIMPLE_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, true)
3084 static inline __printf(1, 2)
3085 void __simple_attr_check_format(const char *fmt
, ...)
3087 /* don't do anything, just let the compiler check the arguments; */
3090 int simple_attr_open(struct inode
*inode
, struct file
*file
,
3091 int (*get
)(void *, u64
*), int (*set
)(void *, u64
),
3093 int simple_attr_release(struct inode
*inode
, struct file
*file
);
3094 ssize_t
simple_attr_read(struct file
*file
, char __user
*buf
,
3095 size_t len
, loff_t
*ppos
);
3096 ssize_t
simple_attr_write(struct file
*file
, const char __user
*buf
,
3097 size_t len
, loff_t
*ppos
);
3098 ssize_t
simple_attr_write_signed(struct file
*file
, const char __user
*buf
,
3099 size_t len
, loff_t
*ppos
);
3102 int __init
list_bdev_fs_names(char *buf
, size_t size
);
3104 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3105 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3107 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3108 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3109 (flag & __FMODE_NONOTIFY)))
3111 static inline bool is_sxid(umode_t mode
)
3113 return mode
& (S_ISUID
| S_ISGID
);
3116 static inline int check_sticky(struct mnt_idmap
*idmap
,
3117 struct inode
*dir
, struct inode
*inode
)
3119 if (!(dir
->i_mode
& S_ISVTX
))
3122 return __check_sticky(idmap
, dir
, inode
);
3125 static inline void inode_has_no_xattr(struct inode
*inode
)
3127 if (!is_sxid(inode
->i_mode
) && (inode
->i_sb
->s_flags
& SB_NOSEC
))
3128 inode
->i_flags
|= S_NOSEC
;
3131 static inline bool is_root_inode(struct inode
*inode
)
3133 return inode
== inode
->i_sb
->s_root
->d_inode
;
3136 static inline bool dir_emit(struct dir_context
*ctx
,
3137 const char *name
, int namelen
,
3138 u64 ino
, unsigned type
)
3140 return ctx
->actor(ctx
, name
, namelen
, ctx
->pos
, ino
, type
);
3142 static inline bool dir_emit_dot(struct file
*file
, struct dir_context
*ctx
)
3144 return ctx
->actor(ctx
, ".", 1, ctx
->pos
,
3145 file
->f_path
.dentry
->d_inode
->i_ino
, DT_DIR
);
3147 static inline bool dir_emit_dotdot(struct file
*file
, struct dir_context
*ctx
)
3149 return ctx
->actor(ctx
, "..", 2, ctx
->pos
,
3150 parent_ino(file
->f_path
.dentry
), DT_DIR
);
3152 static inline bool dir_emit_dots(struct file
*file
, struct dir_context
*ctx
)
3154 if (ctx
->pos
== 0) {
3155 if (!dir_emit_dot(file
, ctx
))
3159 if (ctx
->pos
== 1) {
3160 if (!dir_emit_dotdot(file
, ctx
))
3166 static inline bool dir_relax(struct inode
*inode
)
3168 inode_unlock(inode
);
3170 return !IS_DEADDIR(inode
);
3173 static inline bool dir_relax_shared(struct inode
*inode
)
3175 inode_unlock_shared(inode
);
3176 inode_lock_shared(inode
);
3177 return !IS_DEADDIR(inode
);
3180 extern bool path_noexec(const struct path
*path
);
3181 extern void inode_nohighmem(struct inode
*inode
);
3184 extern int vfs_fadvise(struct file
*file
, loff_t offset
, loff_t len
,
3186 extern int generic_fadvise(struct file
*file
, loff_t offset
, loff_t len
,
3189 #endif /* _LINUX_FS_H */