4 #include <linux/linkage.h>
5 #include <linux/wait_bit.h>
6 #include <linux/kdev_t.h>
7 #include <linux/dcache.h>
8 #include <linux/path.h>
9 #include <linux/stat.h>
10 #include <linux/cache.h>
11 #include <linux/list.h>
12 #include <linux/list_lru.h>
13 #include <linux/llist.h>
14 #include <linux/radix-tree.h>
15 #include <linux/rbtree.h>
16 #include <linux/init.h>
17 #include <linux/pid.h>
18 #include <linux/bug.h>
19 #include <linux/mutex.h>
20 #include <linux/rwsem.h>
21 #include <linux/mm_types.h>
22 #include <linux/capability.h>
23 #include <linux/semaphore.h>
24 #include <linux/fcntl.h>
25 #include <linux/fiemap.h>
26 #include <linux/rculist_bl.h>
27 #include <linux/atomic.h>
28 #include <linux/shrinker.h>
29 #include <linux/migrate_mode.h>
30 #include <linux/uidgid.h>
31 #include <linux/lockdep.h>
32 #include <linux/percpu-rwsem.h>
33 #include <linux/workqueue.h>
34 #include <linux/delayed_call.h>
35 #include <linux/uuid.h>
36 #include <linux/errseq.h>
38 #include <asm/byteorder.h>
39 #include <uapi/linux/fs.h>
41 struct backing_dev_info
;
44 struct export_operations
;
49 struct pipe_inode_info
;
50 struct poll_table_struct
;
52 struct vm_area_struct
;
55 struct swap_info_struct
;
57 struct workqueue_struct
;
60 struct fscrypt_operations
;
62 extern void __init
inode_init(void);
63 extern void __init
inode_init_early(void);
64 extern void __init
files_init(void);
65 extern void __init
files_maxfiles_init(void);
67 extern struct files_stat_struct files_stat
;
68 extern unsigned long get_max_files(void);
69 extern unsigned int sysctl_nr_open
;
70 extern struct inodes_stat_t inodes_stat
;
71 extern int leases_enable
, lease_break_time
;
72 extern int sysctl_protected_symlinks
;
73 extern int sysctl_protected_hardlinks
;
75 typedef __kernel_rwf_t rwf_t
;
78 typedef int (get_block_t
)(struct inode
*inode
, sector_t iblock
,
79 struct buffer_head
*bh_result
, int create
);
80 typedef int (dio_iodone_t
)(struct kiocb
*iocb
, loff_t offset
,
81 ssize_t bytes
, void *private);
83 #define MAY_EXEC 0x00000001
84 #define MAY_WRITE 0x00000002
85 #define MAY_READ 0x00000004
86 #define MAY_APPEND 0x00000008
87 #define MAY_ACCESS 0x00000010
88 #define MAY_OPEN 0x00000020
89 #define MAY_CHDIR 0x00000040
90 /* called from RCU mode, don't block */
91 #define MAY_NOT_BLOCK 0x00000080
94 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
95 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
98 /* file is open for reading */
99 #define FMODE_READ ((__force fmode_t)0x1)
100 /* file is open for writing */
101 #define FMODE_WRITE ((__force fmode_t)0x2)
102 /* file is seekable */
103 #define FMODE_LSEEK ((__force fmode_t)0x4)
104 /* file can be accessed using pread */
105 #define FMODE_PREAD ((__force fmode_t)0x8)
106 /* file can be accessed using pwrite */
107 #define FMODE_PWRITE ((__force fmode_t)0x10)
108 /* File is opened for execution with sys_execve / sys_uselib */
109 #define FMODE_EXEC ((__force fmode_t)0x20)
110 /* File is opened with O_NDELAY (only set for block devices) */
111 #define FMODE_NDELAY ((__force fmode_t)0x40)
112 /* File is opened with O_EXCL (only set for block devices) */
113 #define FMODE_EXCL ((__force fmode_t)0x80)
114 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
115 (specialy hack for floppy.c) */
116 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
117 /* 32bit hashes as llseek() offset (for directories) */
118 #define FMODE_32BITHASH ((__force fmode_t)0x200)
119 /* 64bit hashes as llseek() offset (for directories) */
120 #define FMODE_64BITHASH ((__force fmode_t)0x400)
123 * Don't update ctime and mtime.
125 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
126 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
128 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
130 /* Expect random access pattern */
131 #define FMODE_RANDOM ((__force fmode_t)0x1000)
133 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
134 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
136 /* File is opened with O_PATH; almost nothing can be done with it */
137 #define FMODE_PATH ((__force fmode_t)0x4000)
139 /* File needs atomic accesses to f_pos */
140 #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
141 /* Write access to underlying fs */
142 #define FMODE_WRITER ((__force fmode_t)0x10000)
143 /* Has read method(s) */
144 #define FMODE_CAN_READ ((__force fmode_t)0x20000)
145 /* Has write method(s) */
146 #define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
148 /* File was opened by fanotify and shouldn't generate fanotify events */
149 #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
151 /* File is capable of returning -EAGAIN if AIO will block */
152 #define FMODE_AIO_NOWAIT ((__force fmode_t)0x8000000)
155 * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
156 * that indicates that they should check the contents of the iovec are
157 * valid, but not check the memory that the iovec elements
160 #define CHECK_IOVEC_ONLY -1
163 * Attribute flags. These should be or-ed together to figure out what
166 #define ATTR_MODE (1 << 0)
167 #define ATTR_UID (1 << 1)
168 #define ATTR_GID (1 << 2)
169 #define ATTR_SIZE (1 << 3)
170 #define ATTR_ATIME (1 << 4)
171 #define ATTR_MTIME (1 << 5)
172 #define ATTR_CTIME (1 << 6)
173 #define ATTR_ATIME_SET (1 << 7)
174 #define ATTR_MTIME_SET (1 << 8)
175 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
176 #define ATTR_ATTR_FLAG (1 << 10)
177 #define ATTR_KILL_SUID (1 << 11)
178 #define ATTR_KILL_SGID (1 << 12)
179 #define ATTR_FILE (1 << 13)
180 #define ATTR_KILL_PRIV (1 << 14)
181 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
182 #define ATTR_TIMES_SET (1 << 16)
183 #define ATTR_TOUCH (1 << 17)
186 * Whiteout is represented by a char device. The following constants define the
187 * mode and device number to use.
189 #define WHITEOUT_MODE 0
190 #define WHITEOUT_DEV 0
193 * This is the Inode Attributes structure, used for notify_change(). It
194 * uses the above definitions as flags, to know which values have changed.
195 * Also, in this manner, a Filesystem can look at only the values it cares
196 * about. Basically, these are the attributes that the VFS layer can
197 * request to change from the FS layer.
199 * Derek Atkins <warlord@MIT.EDU> 94-10-20
202 unsigned int ia_valid
;
207 struct timespec ia_atime
;
208 struct timespec ia_mtime
;
209 struct timespec ia_ctime
;
212 * Not an attribute, but an auxiliary info for filesystems wanting to
213 * implement an ftruncate() like method. NOTE: filesystem should
214 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
216 struct file
*ia_file
;
220 * Includes for diskquotas.
222 #include <linux/quota.h>
225 * Maximum number of layers of fs stack. Needs to be limited to
226 * prevent kernel stack overflow
228 #define FILESYSTEM_MAX_STACK_DEPTH 2
231 * enum positive_aop_returns - aop return codes with specific semantics
233 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
234 * completed, that the page is still locked, and
235 * should be considered active. The VM uses this hint
236 * to return the page to the active list -- it won't
237 * be a candidate for writeback again in the near
238 * future. Other callers must be careful to unlock
239 * the page if they get this return. Returned by
242 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
243 * unlocked it and the page might have been truncated.
244 * The caller should back up to acquiring a new page and
245 * trying again. The aop will be taking reasonable
246 * precautions not to livelock. If the caller held a page
247 * reference, it should drop it before retrying. Returned
250 * address_space_operation functions return these large constants to indicate
251 * special semantics to the caller. These are much larger than the bytes in a
252 * page to allow for functions that return the number of bytes operated on in a
256 enum positive_aop_returns
{
257 AOP_WRITEPAGE_ACTIVATE
= 0x80000,
258 AOP_TRUNCATED_PAGE
= 0x80001,
261 #define AOP_FLAG_CONT_EXPAND 0x0001 /* called from cont_expand */
262 #define AOP_FLAG_NOFS 0x0002 /* used by filesystem to direct
263 * helper code (eg buffer layer)
264 * to clear GFP_FS from alloc */
267 * oh the beauties of C type declarations.
270 struct address_space
;
271 struct writeback_control
;
274 * Write life time hint values.
277 WRITE_LIFE_NOT_SET
= 0,
278 WRITE_LIFE_NONE
= RWH_WRITE_LIFE_NONE
,
279 WRITE_LIFE_SHORT
= RWH_WRITE_LIFE_SHORT
,
280 WRITE_LIFE_MEDIUM
= RWH_WRITE_LIFE_MEDIUM
,
281 WRITE_LIFE_LONG
= RWH_WRITE_LIFE_LONG
,
282 WRITE_LIFE_EXTREME
= RWH_WRITE_LIFE_EXTREME
,
285 #define IOCB_EVENTFD (1 << 0)
286 #define IOCB_APPEND (1 << 1)
287 #define IOCB_DIRECT (1 << 2)
288 #define IOCB_HIPRI (1 << 3)
289 #define IOCB_DSYNC (1 << 4)
290 #define IOCB_SYNC (1 << 5)
291 #define IOCB_WRITE (1 << 6)
292 #define IOCB_NOWAIT (1 << 7)
295 struct file
*ki_filp
;
297 void (*ki_complete
)(struct kiocb
*iocb
, long ret
, long ret2
);
300 enum rw_hint ki_hint
;
301 } __randomize_layout
;
303 static inline bool is_sync_kiocb(struct kiocb
*kiocb
)
305 return kiocb
->ki_complete
== NULL
;
309 * "descriptor" for what we're up to with a read.
310 * This allows us to use the same read code yet
311 * have multiple different users of the data that
312 * we read from a file.
314 * The simplest case just copies the data to user
327 typedef int (*read_actor_t
)(read_descriptor_t
*, struct page
*,
328 unsigned long, unsigned long);
330 struct address_space_operations
{
331 int (*writepage
)(struct page
*page
, struct writeback_control
*wbc
);
332 int (*readpage
)(struct file
*, struct page
*);
334 /* Write back some dirty pages from this mapping. */
335 int (*writepages
)(struct address_space
*, struct writeback_control
*);
337 /* Set a page dirty. Return true if this dirtied it */
338 int (*set_page_dirty
)(struct page
*page
);
340 int (*readpages
)(struct file
*filp
, struct address_space
*mapping
,
341 struct list_head
*pages
, unsigned nr_pages
);
343 int (*write_begin
)(struct file
*, struct address_space
*mapping
,
344 loff_t pos
, unsigned len
, unsigned flags
,
345 struct page
**pagep
, void **fsdata
);
346 int (*write_end
)(struct file
*, struct address_space
*mapping
,
347 loff_t pos
, unsigned len
, unsigned copied
,
348 struct page
*page
, void *fsdata
);
350 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
351 sector_t (*bmap
)(struct address_space
*, sector_t
);
352 void (*invalidatepage
) (struct page
*, unsigned int, unsigned int);
353 int (*releasepage
) (struct page
*, gfp_t
);
354 void (*freepage
)(struct page
*);
355 ssize_t (*direct_IO
)(struct kiocb
*, struct iov_iter
*iter
);
357 * migrate the contents of a page to the specified target. If
358 * migrate_mode is MIGRATE_ASYNC, it must not block.
360 int (*migratepage
) (struct address_space
*,
361 struct page
*, struct page
*, enum migrate_mode
);
362 bool (*isolate_page
)(struct page
*, isolate_mode_t
);
363 void (*putback_page
)(struct page
*);
364 int (*launder_page
) (struct page
*);
365 int (*is_partially_uptodate
) (struct page
*, unsigned long,
367 void (*is_dirty_writeback
) (struct page
*, bool *, bool *);
368 int (*error_remove_page
)(struct address_space
*, struct page
*);
370 /* swapfile support */
371 int (*swap_activate
)(struct swap_info_struct
*sis
, struct file
*file
,
373 void (*swap_deactivate
)(struct file
*file
);
376 extern const struct address_space_operations empty_aops
;
379 * pagecache_write_begin/pagecache_write_end must be used by general code
380 * to write into the pagecache.
382 int pagecache_write_begin(struct file
*, struct address_space
*mapping
,
383 loff_t pos
, unsigned len
, unsigned flags
,
384 struct page
**pagep
, void **fsdata
);
386 int pagecache_write_end(struct file
*, struct address_space
*mapping
,
387 loff_t pos
, unsigned len
, unsigned copied
,
388 struct page
*page
, void *fsdata
);
390 struct address_space
{
391 struct inode
*host
; /* owner: inode, block_device */
392 struct radix_tree_root page_tree
; /* radix tree of all pages */
393 spinlock_t tree_lock
; /* and lock protecting it */
394 atomic_t i_mmap_writable
;/* count VM_SHARED mappings */
395 struct rb_root_cached i_mmap
; /* tree of private and shared mappings */
396 struct rw_semaphore i_mmap_rwsem
; /* protect tree, count, list */
397 /* Protected by tree_lock together with the radix tree */
398 unsigned long nrpages
; /* number of total pages */
399 /* number of shadow or DAX exceptional entries */
400 unsigned long nrexceptional
;
401 pgoff_t writeback_index
;/* writeback starts here */
402 const struct address_space_operations
*a_ops
; /* methods */
403 unsigned long flags
; /* error bits */
404 spinlock_t private_lock
; /* for use by the address_space */
405 gfp_t gfp_mask
; /* implicit gfp mask for allocations */
406 struct list_head private_list
; /* ditto */
407 void *private_data
; /* ditto */
409 } __attribute__((aligned(sizeof(long)))) __randomize_layout
;
411 * On most architectures that alignment is already the case; but
412 * must be enforced here for CRIS, to let the least significant bit
413 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
415 struct request_queue
;
417 struct block_device
{
418 dev_t bd_dev
; /* not a kdev_t - it's a search key */
420 struct inode
* bd_inode
; /* will die */
421 struct super_block
* bd_super
;
422 struct mutex bd_mutex
; /* open/close mutex */
426 bool bd_write_holder
;
428 struct list_head bd_holder_disks
;
430 struct block_device
* bd_contains
;
431 unsigned bd_block_size
;
433 struct hd_struct
* bd_part
;
434 /* number of times partitions within this device have been opened. */
435 unsigned bd_part_count
;
437 struct gendisk
* bd_disk
;
438 struct request_queue
* bd_queue
;
439 struct backing_dev_info
*bd_bdi
;
440 struct list_head bd_list
;
442 * Private data. You must have bd_claim'ed the block_device
443 * to use this. NOTE: bd_claim allows an owner to claim
444 * the same device multiple times, the owner must take special
445 * care to not mess up bd_private for that case.
447 unsigned long bd_private
;
449 /* The counter of freeze processes */
450 int bd_fsfreeze_count
;
451 /* Mutex for freeze */
452 struct mutex bd_fsfreeze_mutex
;
453 } __randomize_layout
;
456 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
459 #define PAGECACHE_TAG_DIRTY 0
460 #define PAGECACHE_TAG_WRITEBACK 1
461 #define PAGECACHE_TAG_TOWRITE 2
463 int mapping_tagged(struct address_space
*mapping
, int tag
);
465 static inline void i_mmap_lock_write(struct address_space
*mapping
)
467 down_write(&mapping
->i_mmap_rwsem
);
470 static inline void i_mmap_unlock_write(struct address_space
*mapping
)
472 up_write(&mapping
->i_mmap_rwsem
);
475 static inline void i_mmap_lock_read(struct address_space
*mapping
)
477 down_read(&mapping
->i_mmap_rwsem
);
480 static inline void i_mmap_unlock_read(struct address_space
*mapping
)
482 up_read(&mapping
->i_mmap_rwsem
);
486 * Might pages of this file be mapped into userspace?
488 static inline int mapping_mapped(struct address_space
*mapping
)
490 return !RB_EMPTY_ROOT(&mapping
->i_mmap
.rb_root
);
494 * Might pages of this file have been modified in userspace?
495 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
496 * marks vma as VM_SHARED if it is shared, and the file was opened for
497 * writing i.e. vma may be mprotected writable even if now readonly.
499 * If i_mmap_writable is negative, no new writable mappings are allowed. You
500 * can only deny writable mappings, if none exists right now.
502 static inline int mapping_writably_mapped(struct address_space
*mapping
)
504 return atomic_read(&mapping
->i_mmap_writable
) > 0;
507 static inline int mapping_map_writable(struct address_space
*mapping
)
509 return atomic_inc_unless_negative(&mapping
->i_mmap_writable
) ?
513 static inline void mapping_unmap_writable(struct address_space
*mapping
)
515 atomic_dec(&mapping
->i_mmap_writable
);
518 static inline int mapping_deny_writable(struct address_space
*mapping
)
520 return atomic_dec_unless_positive(&mapping
->i_mmap_writable
) ?
524 static inline void mapping_allow_writable(struct address_space
*mapping
)
526 atomic_inc(&mapping
->i_mmap_writable
);
530 * Use sequence counter to get consistent i_size on 32-bit processors.
532 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
533 #include <linux/seqlock.h>
534 #define __NEED_I_SIZE_ORDERED
535 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
537 #define i_size_ordered_init(inode) do { } while (0)
541 #define ACL_NOT_CACHED ((void *)(-1))
542 #define ACL_DONT_CACHE ((void *)(-3))
544 static inline struct posix_acl
*
545 uncached_acl_sentinel(struct task_struct
*task
)
547 return (void *)task
+ 1;
551 is_uncached_acl(struct posix_acl
*acl
)
553 return (long)acl
& 1;
556 #define IOP_FASTPERM 0x0001
557 #define IOP_LOOKUP 0x0002
558 #define IOP_NOFOLLOW 0x0004
559 #define IOP_XATTR 0x0008
560 #define IOP_DEFAULT_READLINK 0x0010
562 struct fsnotify_mark_connector
;
565 * Keep mostly read-only and often accessed (especially for
566 * the RCU path lookup and 'stat' data) fields at the beginning
567 * of the 'struct inode'
571 unsigned short i_opflags
;
574 unsigned int i_flags
;
576 #ifdef CONFIG_FS_POSIX_ACL
577 struct posix_acl
*i_acl
;
578 struct posix_acl
*i_default_acl
;
581 const struct inode_operations
*i_op
;
582 struct super_block
*i_sb
;
583 struct address_space
*i_mapping
;
585 #ifdef CONFIG_SECURITY
589 /* Stat data, not accessed from path walking */
592 * Filesystems may only read i_nlink directly. They shall use the
593 * following functions for modification:
595 * (set|clear|inc|drop)_nlink
596 * inode_(inc|dec)_link_count
599 const unsigned int i_nlink
;
600 unsigned int __i_nlink
;
604 struct timespec i_atime
;
605 struct timespec i_mtime
;
606 struct timespec i_ctime
;
607 spinlock_t i_lock
; /* i_blocks, i_bytes, maybe i_size */
608 unsigned short i_bytes
;
609 unsigned int i_blkbits
;
610 enum rw_hint i_write_hint
;
613 #ifdef __NEED_I_SIZE_ORDERED
614 seqcount_t i_size_seqcount
;
618 unsigned long i_state
;
619 struct rw_semaphore i_rwsem
;
621 unsigned long dirtied_when
; /* jiffies of first dirtying */
622 unsigned long dirtied_time_when
;
624 struct hlist_node i_hash
;
625 struct list_head i_io_list
; /* backing dev IO list */
626 #ifdef CONFIG_CGROUP_WRITEBACK
627 struct bdi_writeback
*i_wb
; /* the associated cgroup wb */
629 /* foreign inode detection, see wbc_detach_inode() */
631 u16 i_wb_frn_avg_time
;
632 u16 i_wb_frn_history
;
634 struct list_head i_lru
; /* inode LRU list */
635 struct list_head i_sb_list
;
636 struct list_head i_wb_list
; /* backing dev writeback list */
638 struct hlist_head i_dentry
;
639 struct rcu_head i_rcu
;
643 atomic_t i_dio_count
;
644 atomic_t i_writecount
;
646 atomic_t i_readcount
; /* struct files open RO */
648 const struct file_operations
*i_fop
; /* former ->i_op->default_file_ops */
649 struct file_lock_context
*i_flctx
;
650 struct address_space i_data
;
651 struct list_head i_devices
;
653 struct pipe_inode_info
*i_pipe
;
654 struct block_device
*i_bdev
;
662 #ifdef CONFIG_FSNOTIFY
663 __u32 i_fsnotify_mask
; /* all events this inode cares about */
664 struct fsnotify_mark_connector __rcu
*i_fsnotify_marks
;
667 #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
668 struct fscrypt_info
*i_crypt_info
;
671 void *i_private
; /* fs or device private pointer */
672 } __randomize_layout
;
674 static inline unsigned int i_blocksize(const struct inode
*node
)
676 return (1 << node
->i_blkbits
);
679 static inline int inode_unhashed(struct inode
*inode
)
681 return hlist_unhashed(&inode
->i_hash
);
685 * inode->i_mutex nesting subclasses for the lock validator:
687 * 0: the object of the current VFS operation
691 * 4: second non-directory
692 * 5: second parent (when locking independent directories in rename)
694 * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
695 * non-directories at once.
697 * The locking order between these classes is
698 * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
700 enum inode_i_mutex_lock_class
710 static inline void inode_lock(struct inode
*inode
)
712 down_write(&inode
->i_rwsem
);
715 static inline void inode_unlock(struct inode
*inode
)
717 up_write(&inode
->i_rwsem
);
720 static inline void inode_lock_shared(struct inode
*inode
)
722 down_read(&inode
->i_rwsem
);
725 static inline void inode_unlock_shared(struct inode
*inode
)
727 up_read(&inode
->i_rwsem
);
730 static inline int inode_trylock(struct inode
*inode
)
732 return down_write_trylock(&inode
->i_rwsem
);
735 static inline int inode_trylock_shared(struct inode
*inode
)
737 return down_read_trylock(&inode
->i_rwsem
);
740 static inline int inode_is_locked(struct inode
*inode
)
742 return rwsem_is_locked(&inode
->i_rwsem
);
745 static inline void inode_lock_nested(struct inode
*inode
, unsigned subclass
)
747 down_write_nested(&inode
->i_rwsem
, subclass
);
750 void lock_two_nondirectories(struct inode
*, struct inode
*);
751 void unlock_two_nondirectories(struct inode
*, struct inode
*);
754 * NOTE: in a 32bit arch with a preemptable kernel and
755 * an UP compile the i_size_read/write must be atomic
756 * with respect to the local cpu (unlike with preempt disabled),
757 * but they don't need to be atomic with respect to other cpus like in
758 * true SMP (so they need either to either locally disable irq around
759 * the read or for example on x86 they can be still implemented as a
760 * cmpxchg8b without the need of the lock prefix). For SMP compiles
761 * and 64bit archs it makes no difference if preempt is enabled or not.
763 static inline loff_t
i_size_read(const struct inode
*inode
)
765 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
770 seq
= read_seqcount_begin(&inode
->i_size_seqcount
);
771 i_size
= inode
->i_size
;
772 } while (read_seqcount_retry(&inode
->i_size_seqcount
, seq
));
774 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
778 i_size
= inode
->i_size
;
782 return inode
->i_size
;
787 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
788 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
789 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
791 static inline void i_size_write(struct inode
*inode
, loff_t i_size
)
793 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
795 write_seqcount_begin(&inode
->i_size_seqcount
);
796 inode
->i_size
= i_size
;
797 write_seqcount_end(&inode
->i_size_seqcount
);
799 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
801 inode
->i_size
= i_size
;
804 inode
->i_size
= i_size
;
808 static inline unsigned iminor(const struct inode
*inode
)
810 return MINOR(inode
->i_rdev
);
813 static inline unsigned imajor(const struct inode
*inode
)
815 return MAJOR(inode
->i_rdev
);
818 extern struct block_device
*I_BDEV(struct inode
*inode
);
821 rwlock_t lock
; /* protects pid, uid, euid fields */
822 struct pid
*pid
; /* pid or -pgrp where SIGIO should be sent */
823 enum pid_type pid_type
; /* Kind of process group SIGIO should be sent to */
824 kuid_t uid
, euid
; /* uid/euid of process setting the owner */
825 int signum
; /* posix.1b rt signal to be delivered on IO */
829 * Track a single file's readahead state
831 struct file_ra_state
{
832 pgoff_t start
; /* where readahead started */
833 unsigned int size
; /* # of readahead pages */
834 unsigned int async_size
; /* do asynchronous readahead when
835 there are only # of pages ahead */
837 unsigned int ra_pages
; /* Maximum readahead window */
838 unsigned int mmap_miss
; /* Cache miss stat for mmap accesses */
839 loff_t prev_pos
; /* Cache last read() position */
843 * Check if @index falls in the readahead windows.
845 static inline int ra_has_index(struct file_ra_state
*ra
, pgoff_t index
)
847 return (index
>= ra
->start
&&
848 index
< ra
->start
+ ra
->size
);
853 struct llist_node fu_llist
;
854 struct rcu_head fu_rcuhead
;
857 struct inode
*f_inode
; /* cached value */
858 const struct file_operations
*f_op
;
861 * Protects f_ep_links, f_flags.
862 * Must not be taken from IRQ context.
865 enum rw_hint f_write_hint
;
866 atomic_long_t f_count
;
867 unsigned int f_flags
;
869 struct mutex f_pos_lock
;
871 struct fown_struct f_owner
;
872 const struct cred
*f_cred
;
873 struct file_ra_state f_ra
;
876 #ifdef CONFIG_SECURITY
879 /* needed for tty driver, and maybe others */
883 /* Used by fs/eventpoll.c to link all the hooks to this file */
884 struct list_head f_ep_links
;
885 struct list_head f_tfile_llink
;
886 #endif /* #ifdef CONFIG_EPOLL */
887 struct address_space
*f_mapping
;
890 __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
895 /* file identifier */
896 unsigned char f_handle
[0];
899 static inline struct file
*get_file(struct file
*f
)
901 atomic_long_inc(&f
->f_count
);
904 #define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
905 #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
906 #define file_count(x) atomic_long_read(&(x)->f_count)
908 #define MAX_NON_LFS ((1UL<<31) - 1)
910 /* Page cache limit. The filesystems should put that into their s_maxbytes
911 limits, otherwise bad things can happen in VM. */
912 #if BITS_PER_LONG==32
913 #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT)
914 #elif BITS_PER_LONG==64
915 #define MAX_LFS_FILESIZE ((loff_t)LLONG_MAX)
920 #define FL_DELEG 4 /* NFSv4 delegation */
921 #define FL_ACCESS 8 /* not trying to lock, just looking */
922 #define FL_EXISTS 16 /* when unlocking, test for existence */
923 #define FL_LEASE 32 /* lease held on this file */
924 #define FL_CLOSE 64 /* unlock on close */
925 #define FL_SLEEP 128 /* A blocking lock */
926 #define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
927 #define FL_UNLOCK_PENDING 512 /* Lease is being broken */
928 #define FL_OFDLCK 1024 /* lock is "owned" by struct file */
929 #define FL_LAYOUT 2048 /* outstanding pNFS layout */
931 #define FL_CLOSE_POSIX (FL_POSIX | FL_CLOSE)
934 * Special return value from posix_lock_file() and vfs_lock_file() for
935 * asynchronous locking.
937 #define FILE_LOCK_DEFERRED 1
939 /* legacy typedef, should eventually be removed */
940 typedef void *fl_owner_t
;
944 struct file_lock_operations
{
945 void (*fl_copy_lock
)(struct file_lock
*, struct file_lock
*);
946 void (*fl_release_private
)(struct file_lock
*);
949 struct lock_manager_operations
{
950 int (*lm_compare_owner
)(struct file_lock
*, struct file_lock
*);
951 unsigned long (*lm_owner_key
)(struct file_lock
*);
952 fl_owner_t (*lm_get_owner
)(fl_owner_t
);
953 void (*lm_put_owner
)(fl_owner_t
);
954 void (*lm_notify
)(struct file_lock
*); /* unblock callback */
955 int (*lm_grant
)(struct file_lock
*, int);
956 bool (*lm_break
)(struct file_lock
*);
957 int (*lm_change
)(struct file_lock
*, int, struct list_head
*);
958 void (*lm_setup
)(struct file_lock
*, void **);
961 struct lock_manager
{
962 struct list_head list
;
964 * NFSv4 and up also want opens blocked during the grace period;
971 void locks_start_grace(struct net
*, struct lock_manager
*);
972 void locks_end_grace(struct lock_manager
*);
973 int locks_in_grace(struct net
*);
974 int opens_in_grace(struct net
*);
976 /* that will die - we need it for nfs_lock_info */
977 #include <linux/nfs_fs_i.h>
980 * struct file_lock represents a generic "file lock". It's used to represent
981 * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
982 * note that the same struct is used to represent both a request for a lock and
983 * the lock itself, but the same object is never used for both.
985 * FIXME: should we create a separate "struct lock_request" to help distinguish
988 * The varous i_flctx lists are ordered by:
991 * 2) lock range start
994 * Obviously, the last two criteria only matter for POSIX locks.
997 struct file_lock
*fl_next
; /* singly linked list for this inode */
998 struct list_head fl_list
; /* link into file_lock_context */
999 struct hlist_node fl_link
; /* node in global lists */
1000 struct list_head fl_block
; /* circular list of blocked processes */
1001 fl_owner_t fl_owner
;
1002 unsigned int fl_flags
;
1003 unsigned char fl_type
;
1004 unsigned int fl_pid
;
1005 int fl_link_cpu
; /* what cpu's list is this on? */
1006 wait_queue_head_t fl_wait
;
1007 struct file
*fl_file
;
1011 struct fasync_struct
* fl_fasync
; /* for lease break notifications */
1012 /* for lease breaks: */
1013 unsigned long fl_break_time
;
1014 unsigned long fl_downgrade_time
;
1016 const struct file_lock_operations
*fl_ops
; /* Callbacks for filesystems */
1017 const struct lock_manager_operations
*fl_lmops
; /* Callbacks for lockmanagers */
1019 struct nfs_lock_info nfs_fl
;
1020 struct nfs4_lock_info nfs4_fl
;
1022 struct list_head link
; /* link in AFS vnode's pending_locks list */
1023 int state
; /* state of grant or error if -ve */
1026 } __randomize_layout
;
1028 struct file_lock_context
{
1029 spinlock_t flc_lock
;
1030 struct list_head flc_flock
;
1031 struct list_head flc_posix
;
1032 struct list_head flc_lease
;
1035 /* The following constant reflects the upper bound of the file/locking space */
1037 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
1038 #define OFFSET_MAX INT_LIMIT(loff_t)
1039 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
1042 extern void send_sigio(struct fown_struct
*fown
, int fd
, int band
);
1045 * Return the inode to use for locking
1047 * For overlayfs this should be the overlay inode, not the real inode returned
1048 * by file_inode(). For any other fs file_inode(filp) and locks_inode(filp) are
1051 static inline struct inode
*locks_inode(const struct file
*f
)
1053 return f
->f_path
.dentry
->d_inode
;
1056 #ifdef CONFIG_FILE_LOCKING
1057 extern int fcntl_getlk(struct file
*, unsigned int, struct flock
*);
1058 extern int fcntl_setlk(unsigned int, struct file
*, unsigned int,
1061 #if BITS_PER_LONG == 32
1062 extern int fcntl_getlk64(struct file
*, unsigned int, struct flock64
*);
1063 extern int fcntl_setlk64(unsigned int, struct file
*, unsigned int,
1067 extern int fcntl_setlease(unsigned int fd
, struct file
*filp
, long arg
);
1068 extern int fcntl_getlease(struct file
*filp
);
1071 void locks_free_lock_context(struct inode
*inode
);
1072 void locks_free_lock(struct file_lock
*fl
);
1073 extern void locks_init_lock(struct file_lock
*);
1074 extern struct file_lock
* locks_alloc_lock(void);
1075 extern void locks_copy_lock(struct file_lock
*, struct file_lock
*);
1076 extern void locks_copy_conflock(struct file_lock
*, struct file_lock
*);
1077 extern void locks_remove_posix(struct file
*, fl_owner_t
);
1078 extern void locks_remove_file(struct file
*);
1079 extern void locks_release_private(struct file_lock
*);
1080 extern void posix_test_lock(struct file
*, struct file_lock
*);
1081 extern int posix_lock_file(struct file
*, struct file_lock
*, struct file_lock
*);
1082 extern int posix_unblock_lock(struct file_lock
*);
1083 extern int vfs_test_lock(struct file
*, struct file_lock
*);
1084 extern int vfs_lock_file(struct file
*, unsigned int, struct file_lock
*, struct file_lock
*);
1085 extern int vfs_cancel_lock(struct file
*filp
, struct file_lock
*fl
);
1086 extern int locks_lock_inode_wait(struct inode
*inode
, struct file_lock
*fl
);
1087 extern int __break_lease(struct inode
*inode
, unsigned int flags
, unsigned int type
);
1088 extern void lease_get_mtime(struct inode
*, struct timespec
*time
);
1089 extern int generic_setlease(struct file
*, long, struct file_lock
**, void **priv
);
1090 extern int vfs_setlease(struct file
*, long, struct file_lock
**, void **);
1091 extern int lease_modify(struct file_lock
*, int, struct list_head
*);
1092 struct files_struct
;
1093 extern void show_fd_locks(struct seq_file
*f
,
1094 struct file
*filp
, struct files_struct
*files
);
1095 #else /* !CONFIG_FILE_LOCKING */
1096 static inline int fcntl_getlk(struct file
*file
, unsigned int cmd
,
1097 struct flock __user
*user
)
1102 static inline int fcntl_setlk(unsigned int fd
, struct file
*file
,
1103 unsigned int cmd
, struct flock __user
*user
)
1108 #if BITS_PER_LONG == 32
1109 static inline int fcntl_getlk64(struct file
*file
, unsigned int cmd
,
1110 struct flock64 __user
*user
)
1115 static inline int fcntl_setlk64(unsigned int fd
, struct file
*file
,
1116 unsigned int cmd
, struct flock64 __user
*user
)
1121 static inline int fcntl_setlease(unsigned int fd
, struct file
*filp
, long arg
)
1126 static inline int fcntl_getlease(struct file
*filp
)
1132 locks_free_lock_context(struct inode
*inode
)
1136 static inline void locks_init_lock(struct file_lock
*fl
)
1141 static inline void locks_copy_conflock(struct file_lock
*new, struct file_lock
*fl
)
1146 static inline void locks_copy_lock(struct file_lock
*new, struct file_lock
*fl
)
1151 static inline void locks_remove_posix(struct file
*filp
, fl_owner_t owner
)
1156 static inline void locks_remove_file(struct file
*filp
)
1161 static inline void posix_test_lock(struct file
*filp
, struct file_lock
*fl
)
1166 static inline int posix_lock_file(struct file
*filp
, struct file_lock
*fl
,
1167 struct file_lock
*conflock
)
1172 static inline int posix_unblock_lock(struct file_lock
*waiter
)
1177 static inline int vfs_test_lock(struct file
*filp
, struct file_lock
*fl
)
1182 static inline int vfs_lock_file(struct file
*filp
, unsigned int cmd
,
1183 struct file_lock
*fl
, struct file_lock
*conf
)
1188 static inline int vfs_cancel_lock(struct file
*filp
, struct file_lock
*fl
)
1193 static inline int locks_lock_inode_wait(struct inode
*inode
, struct file_lock
*fl
)
1198 static inline int __break_lease(struct inode
*inode
, unsigned int mode
, unsigned int type
)
1203 static inline void lease_get_mtime(struct inode
*inode
, struct timespec
*time
)
1208 static inline int generic_setlease(struct file
*filp
, long arg
,
1209 struct file_lock
**flp
, void **priv
)
1214 static inline int vfs_setlease(struct file
*filp
, long arg
,
1215 struct file_lock
**lease
, void **priv
)
1220 static inline int lease_modify(struct file_lock
*fl
, int arg
,
1221 struct list_head
*dispose
)
1226 struct files_struct
;
1227 static inline void show_fd_locks(struct seq_file
*f
,
1228 struct file
*filp
, struct files_struct
*files
) {}
1229 #endif /* !CONFIG_FILE_LOCKING */
1231 static inline struct inode
*file_inode(const struct file
*f
)
1236 static inline struct dentry
*file_dentry(const struct file
*file
)
1238 return d_real(file
->f_path
.dentry
, file_inode(file
), 0);
1241 static inline int locks_lock_file_wait(struct file
*filp
, struct file_lock
*fl
)
1243 return locks_lock_inode_wait(locks_inode(filp
), fl
);
1246 struct fasync_struct
{
1250 struct fasync_struct
*fa_next
; /* singly linked list */
1251 struct file
*fa_file
;
1252 struct rcu_head fa_rcu
;
1255 #define FASYNC_MAGIC 0x4601
1257 /* SMP safe fasync helpers: */
1258 extern int fasync_helper(int, struct file
*, int, struct fasync_struct
**);
1259 extern struct fasync_struct
*fasync_insert_entry(int, struct file
*, struct fasync_struct
**, struct fasync_struct
*);
1260 extern int fasync_remove_entry(struct file
*, struct fasync_struct
**);
1261 extern struct fasync_struct
*fasync_alloc(void);
1262 extern void fasync_free(struct fasync_struct
*);
1264 /* can be called from interrupts */
1265 extern void kill_fasync(struct fasync_struct
**, int, int);
1267 extern void __f_setown(struct file
*filp
, struct pid
*, enum pid_type
, int force
);
1268 extern int f_setown(struct file
*filp
, unsigned long arg
, int force
);
1269 extern void f_delown(struct file
*filp
);
1270 extern pid_t
f_getown(struct file
*filp
);
1271 extern int send_sigurg(struct fown_struct
*fown
);
1277 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1278 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1279 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1280 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1281 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1284 #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1285 #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1286 #define SB_I_NODEV 0x00000004 /* Ignore devices on this fs */
1288 /* sb->s_iflags to limit user namespace mounts */
1289 #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */
1291 /* Possible states of 'frozen' field */
1293 SB_UNFROZEN
= 0, /* FS is unfrozen */
1294 SB_FREEZE_WRITE
= 1, /* Writes, dir ops, ioctls frozen */
1295 SB_FREEZE_PAGEFAULT
= 2, /* Page faults stopped as well */
1296 SB_FREEZE_FS
= 3, /* For internal FS use (e.g. to stop
1297 * internal threads if needed) */
1298 SB_FREEZE_COMPLETE
= 4, /* ->freeze_fs finished successfully */
1301 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1304 int frozen
; /* Is sb frozen? */
1305 wait_queue_head_t wait_unfrozen
; /* for get_super_thawed() */
1306 struct percpu_rw_semaphore rw_sem
[SB_FREEZE_LEVELS
];
1309 struct super_block
{
1310 struct list_head s_list
; /* Keep this first */
1311 dev_t s_dev
; /* search index; _not_ kdev_t */
1312 unsigned char s_blocksize_bits
;
1313 unsigned long s_blocksize
;
1314 loff_t s_maxbytes
; /* Max file size */
1315 struct file_system_type
*s_type
;
1316 const struct super_operations
*s_op
;
1317 const struct dquot_operations
*dq_op
;
1318 const struct quotactl_ops
*s_qcop
;
1319 const struct export_operations
*s_export_op
;
1320 unsigned long s_flags
;
1321 unsigned long s_iflags
; /* internal SB_I_* flags */
1322 unsigned long s_magic
;
1323 struct dentry
*s_root
;
1324 struct rw_semaphore s_umount
;
1327 #ifdef CONFIG_SECURITY
1330 const struct xattr_handler
**s_xattr
;
1332 const struct fscrypt_operations
*s_cop
;
1334 struct hlist_bl_head s_anon
; /* anonymous dentries for (nfs) exporting */
1335 struct list_head s_mounts
; /* list of mounts; _not_ for fs use */
1336 struct block_device
*s_bdev
;
1337 struct backing_dev_info
*s_bdi
;
1338 struct mtd_info
*s_mtd
;
1339 struct hlist_node s_instances
;
1340 unsigned int s_quota_types
; /* Bitmask of supported quota types */
1341 struct quota_info s_dquot
; /* Diskquota specific options */
1343 struct sb_writers s_writers
;
1345 char s_id
[32]; /* Informational name */
1346 uuid_t s_uuid
; /* UUID */
1348 void *s_fs_info
; /* Filesystem private info */
1349 unsigned int s_max_links
;
1352 /* Granularity of c/m/atime in ns.
1353 Cannot be worse than a second */
1357 * The next field is for VFS *only*. No filesystems have any business
1358 * even looking at it. You had been warned.
1360 struct mutex s_vfs_rename_mutex
; /* Kludge */
1363 * Filesystem subtype. If non-empty the filesystem type field
1364 * in /proc/mounts will be "type.subtype"
1368 const struct dentry_operations
*s_d_op
; /* default d_op for dentries */
1371 * Saved pool identifier for cleancache (-1 means none)
1373 int cleancache_poolid
;
1375 struct shrinker s_shrink
; /* per-sb shrinker handle */
1377 /* Number of inodes with nlink == 0 but still referenced */
1378 atomic_long_t s_remove_count
;
1380 /* Being remounted read-only */
1381 int s_readonly_remount
;
1383 /* AIO completions deferred from interrupt context */
1384 struct workqueue_struct
*s_dio_done_wq
;
1385 struct hlist_head s_pins
;
1388 * Owning user namespace and default context in which to
1389 * interpret filesystem uids, gids, quotas, device nodes,
1390 * xattrs and security labels.
1392 struct user_namespace
*s_user_ns
;
1395 * Keep the lru lists last in the structure so they always sit on their
1396 * own individual cachelines.
1398 struct list_lru s_dentry_lru ____cacheline_aligned_in_smp
;
1399 struct list_lru s_inode_lru ____cacheline_aligned_in_smp
;
1400 struct rcu_head rcu
;
1401 struct work_struct destroy_work
;
1403 struct mutex s_sync_lock
; /* sync serialisation lock */
1406 * Indicates how deep in a filesystem stack this SB is
1410 /* s_inode_list_lock protects s_inodes */
1411 spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp
;
1412 struct list_head s_inodes
; /* all inodes */
1414 spinlock_t s_inode_wblist_lock
;
1415 struct list_head s_inodes_wb
; /* writeback inodes */
1416 } __randomize_layout
;
1418 /* Helper functions so that in most cases filesystems will
1419 * not need to deal directly with kuid_t and kgid_t and can
1420 * instead deal with the raw numeric values that are stored
1421 * in the filesystem.
1423 static inline uid_t
i_uid_read(const struct inode
*inode
)
1425 return from_kuid(inode
->i_sb
->s_user_ns
, inode
->i_uid
);
1428 static inline gid_t
i_gid_read(const struct inode
*inode
)
1430 return from_kgid(inode
->i_sb
->s_user_ns
, inode
->i_gid
);
1433 static inline void i_uid_write(struct inode
*inode
, uid_t uid
)
1435 inode
->i_uid
= make_kuid(inode
->i_sb
->s_user_ns
, uid
);
1438 static inline void i_gid_write(struct inode
*inode
, gid_t gid
)
1440 inode
->i_gid
= make_kgid(inode
->i_sb
->s_user_ns
, gid
);
1443 extern struct timespec
current_time(struct inode
*inode
);
1446 * Snapshotting support.
1449 void __sb_end_write(struct super_block
*sb
, int level
);
1450 int __sb_start_write(struct super_block
*sb
, int level
, bool wait
);
1452 #define __sb_writers_acquired(sb, lev) \
1453 percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1454 #define __sb_writers_release(sb, lev) \
1455 percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1458 * sb_end_write - drop write access to a superblock
1459 * @sb: the super we wrote to
1461 * Decrement number of writers to the filesystem. Wake up possible waiters
1462 * wanting to freeze the filesystem.
1464 static inline void sb_end_write(struct super_block
*sb
)
1466 __sb_end_write(sb
, SB_FREEZE_WRITE
);
1470 * sb_end_pagefault - drop write access to a superblock from a page fault
1471 * @sb: the super we wrote to
1473 * Decrement number of processes handling write page fault to the filesystem.
1474 * Wake up possible waiters wanting to freeze the filesystem.
1476 static inline void sb_end_pagefault(struct super_block
*sb
)
1478 __sb_end_write(sb
, SB_FREEZE_PAGEFAULT
);
1482 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1483 * @sb: the super we wrote to
1485 * Decrement fs-internal number of writers to the filesystem. Wake up possible
1486 * waiters wanting to freeze the filesystem.
1488 static inline void sb_end_intwrite(struct super_block
*sb
)
1490 __sb_end_write(sb
, SB_FREEZE_FS
);
1494 * sb_start_write - get write access to a superblock
1495 * @sb: the super we write to
1497 * When a process wants to write data or metadata to a file system (i.e. dirty
1498 * a page or an inode), it should embed the operation in a sb_start_write() -
1499 * sb_end_write() pair to get exclusion against file system freezing. This
1500 * function increments number of writers preventing freezing. If the file
1501 * system is already frozen, the function waits until the file system is
1504 * Since freeze protection behaves as a lock, users have to preserve
1505 * ordering of freeze protection and other filesystem locks. Generally,
1506 * freeze protection should be the outermost lock. In particular, we have:
1509 * -> i_mutex (write path, truncate, directory ops, ...)
1510 * -> s_umount (freeze_super, thaw_super)
1512 static inline void sb_start_write(struct super_block
*sb
)
1514 __sb_start_write(sb
, SB_FREEZE_WRITE
, true);
1517 static inline int sb_start_write_trylock(struct super_block
*sb
)
1519 return __sb_start_write(sb
, SB_FREEZE_WRITE
, false);
1523 * sb_start_pagefault - get write access to a superblock from a page fault
1524 * @sb: the super we write to
1526 * When a process starts handling write page fault, it should embed the
1527 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1528 * exclusion against file system freezing. This is needed since the page fault
1529 * is going to dirty a page. This function increments number of running page
1530 * faults preventing freezing. If the file system is already frozen, the
1531 * function waits until the file system is thawed.
1533 * Since page fault freeze protection behaves as a lock, users have to preserve
1534 * ordering of freeze protection and other filesystem locks. It is advised to
1535 * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
1536 * handling code implies lock dependency:
1539 * -> sb_start_pagefault
1541 static inline void sb_start_pagefault(struct super_block
*sb
)
1543 __sb_start_write(sb
, SB_FREEZE_PAGEFAULT
, true);
1547 * sb_start_intwrite - get write access to a superblock for internal fs purposes
1548 * @sb: the super we write to
1550 * This is the third level of protection against filesystem freezing. It is
1551 * free for use by a filesystem. The only requirement is that it must rank
1552 * below sb_start_pagefault.
1554 * For example filesystem can call sb_start_intwrite() when starting a
1555 * transaction which somewhat eases handling of freezing for internal sources
1556 * of filesystem changes (internal fs threads, discarding preallocation on file
1559 static inline void sb_start_intwrite(struct super_block
*sb
)
1561 __sb_start_write(sb
, SB_FREEZE_FS
, true);
1565 extern bool inode_owner_or_capable(const struct inode
*inode
);
1568 * VFS helper functions..
1570 extern int vfs_create(struct inode
*, struct dentry
*, umode_t
, bool);
1571 extern int vfs_mkdir(struct inode
*, struct dentry
*, umode_t
);
1572 extern int vfs_mknod(struct inode
*, struct dentry
*, umode_t
, dev_t
);
1573 extern int vfs_symlink(struct inode
*, struct dentry
*, const char *);
1574 extern int vfs_link(struct dentry
*, struct inode
*, struct dentry
*, struct inode
**);
1575 extern int vfs_rmdir(struct inode
*, struct dentry
*);
1576 extern int vfs_unlink(struct inode
*, struct dentry
*, struct inode
**);
1577 extern int vfs_rename(struct inode
*, struct dentry
*, struct inode
*, struct dentry
*, struct inode
**, unsigned int);
1578 extern int vfs_whiteout(struct inode
*, struct dentry
*);
1580 extern struct dentry
*vfs_tmpfile(struct dentry
*dentry
, umode_t mode
,
1584 * VFS file helper functions.
1586 extern void inode_init_owner(struct inode
*inode
, const struct inode
*dir
,
1588 extern bool may_open_dev(const struct path
*path
);
1590 * VFS FS_IOC_FIEMAP helper definitions.
1592 struct fiemap_extent_info
{
1593 unsigned int fi_flags
; /* Flags as passed from user */
1594 unsigned int fi_extents_mapped
; /* Number of mapped extents */
1595 unsigned int fi_extents_max
; /* Size of fiemap_extent array */
1596 struct fiemap_extent __user
*fi_extents_start
; /* Start of
1597 fiemap_extent array */
1599 int fiemap_fill_next_extent(struct fiemap_extent_info
*info
, u64 logical
,
1600 u64 phys
, u64 len
, u32 flags
);
1601 int fiemap_check_flags(struct fiemap_extent_info
*fieinfo
, u32 fs_flags
);
1606 * NOTE! These match bits 12..15 of stat.st_mode
1607 * (ie "(i_mode >> 12) & 15").
1609 #define DT_UNKNOWN 0
1620 * This is the "filldir" function type, used by readdir() to let
1621 * the kernel specify what kind of dirent layout it wants to have.
1622 * This allows the kernel to read directories into kernel space or
1623 * to have different dirent layouts depending on the binary type.
1626 typedef int (*filldir_t
)(struct dir_context
*, const char *, int, loff_t
, u64
,
1629 struct dir_context
{
1630 const filldir_t actor
;
1634 struct block_device_operations
;
1636 /* These macros are for out of kernel modules to test that
1637 * the kernel supports the unlocked_ioctl and compat_ioctl
1638 * fields in struct file_operations. */
1639 #define HAVE_COMPAT_IOCTL 1
1640 #define HAVE_UNLOCKED_IOCTL 1
1643 * These flags let !MMU mmap() govern direct device mapping vs immediate
1644 * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1646 * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1647 * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1648 * NOMMU_MAP_READ: Can be mapped for reading
1649 * NOMMU_MAP_WRITE: Can be mapped for writing
1650 * NOMMU_MAP_EXEC: Can be mapped for execution
1652 #define NOMMU_MAP_COPY 0x00000001
1653 #define NOMMU_MAP_DIRECT 0x00000008
1654 #define NOMMU_MAP_READ VM_MAYREAD
1655 #define NOMMU_MAP_WRITE VM_MAYWRITE
1656 #define NOMMU_MAP_EXEC VM_MAYEXEC
1658 #define NOMMU_VMFLAGS \
1659 (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1664 struct file_operations
{
1665 struct module
*owner
;
1666 loff_t (*llseek
) (struct file
*, loff_t
, int);
1667 ssize_t (*read
) (struct file
*, char __user
*, size_t, loff_t
*);
1668 ssize_t (*write
) (struct file
*, const char __user
*, size_t, loff_t
*);
1669 ssize_t (*read_iter
) (struct kiocb
*, struct iov_iter
*);
1670 ssize_t (*write_iter
) (struct kiocb
*, struct iov_iter
*);
1671 int (*iterate
) (struct file
*, struct dir_context
*);
1672 int (*iterate_shared
) (struct file
*, struct dir_context
*);
1673 unsigned int (*poll
) (struct file
*, struct poll_table_struct
*);
1674 long (*unlocked_ioctl
) (struct file
*, unsigned int, unsigned long);
1675 long (*compat_ioctl
) (struct file
*, unsigned int, unsigned long);
1676 int (*mmap
) (struct file
*, struct vm_area_struct
*);
1677 int (*open
) (struct inode
*, struct file
*);
1678 int (*flush
) (struct file
*, fl_owner_t id
);
1679 int (*release
) (struct inode
*, struct file
*);
1680 int (*fsync
) (struct file
*, loff_t
, loff_t
, int datasync
);
1681 int (*fasync
) (int, struct file
*, int);
1682 int (*lock
) (struct file
*, int, struct file_lock
*);
1683 ssize_t (*sendpage
) (struct file
*, struct page
*, int, size_t, loff_t
*, int);
1684 unsigned long (*get_unmapped_area
)(struct file
*, unsigned long, unsigned long, unsigned long, unsigned long);
1685 int (*check_flags
)(int);
1686 int (*flock
) (struct file
*, int, struct file_lock
*);
1687 ssize_t (*splice_write
)(struct pipe_inode_info
*, struct file
*, loff_t
*, size_t, unsigned int);
1688 ssize_t (*splice_read
)(struct file
*, loff_t
*, struct pipe_inode_info
*, size_t, unsigned int);
1689 int (*setlease
)(struct file
*, long, struct file_lock
**, void **);
1690 long (*fallocate
)(struct file
*file
, int mode
, loff_t offset
,
1692 void (*show_fdinfo
)(struct seq_file
*m
, struct file
*f
);
1694 unsigned (*mmap_capabilities
)(struct file
*);
1696 ssize_t (*copy_file_range
)(struct file
*, loff_t
, struct file
*,
1697 loff_t
, size_t, unsigned int);
1698 int (*clone_file_range
)(struct file
*, loff_t
, struct file
*, loff_t
,
1700 ssize_t (*dedupe_file_range
)(struct file
*, u64
, u64
, struct file
*,
1702 } __randomize_layout
;
1704 struct inode_operations
{
1705 struct dentry
* (*lookup
) (struct inode
*,struct dentry
*, unsigned int);
1706 const char * (*get_link
) (struct dentry
*, struct inode
*, struct delayed_call
*);
1707 int (*permission
) (struct inode
*, int);
1708 struct posix_acl
* (*get_acl
)(struct inode
*, int);
1710 int (*readlink
) (struct dentry
*, char __user
*,int);
1712 int (*create
) (struct inode
*,struct dentry
*, umode_t
, bool);
1713 int (*link
) (struct dentry
*,struct inode
*,struct dentry
*);
1714 int (*unlink
) (struct inode
*,struct dentry
*);
1715 int (*symlink
) (struct inode
*,struct dentry
*,const char *);
1716 int (*mkdir
) (struct inode
*,struct dentry
*,umode_t
);
1717 int (*rmdir
) (struct inode
*,struct dentry
*);
1718 int (*mknod
) (struct inode
*,struct dentry
*,umode_t
,dev_t
);
1719 int (*rename
) (struct inode
*, struct dentry
*,
1720 struct inode
*, struct dentry
*, unsigned int);
1721 int (*setattr
) (struct dentry
*, struct iattr
*);
1722 int (*getattr
) (const struct path
*, struct kstat
*, u32
, unsigned int);
1723 ssize_t (*listxattr
) (struct dentry
*, char *, size_t);
1724 int (*fiemap
)(struct inode
*, struct fiemap_extent_info
*, u64 start
,
1726 int (*update_time
)(struct inode
*, struct timespec
*, int);
1727 int (*atomic_open
)(struct inode
*, struct dentry
*,
1728 struct file
*, unsigned open_flag
,
1729 umode_t create_mode
, int *opened
);
1730 int (*tmpfile
) (struct inode
*, struct dentry
*, umode_t
);
1731 int (*set_acl
)(struct inode
*, struct posix_acl
*, int);
1732 } ____cacheline_aligned
;
1734 static inline ssize_t
call_read_iter(struct file
*file
, struct kiocb
*kio
,
1735 struct iov_iter
*iter
)
1737 return file
->f_op
->read_iter(kio
, iter
);
1740 static inline ssize_t
call_write_iter(struct file
*file
, struct kiocb
*kio
,
1741 struct iov_iter
*iter
)
1743 return file
->f_op
->write_iter(kio
, iter
);
1746 static inline int call_mmap(struct file
*file
, struct vm_area_struct
*vma
)
1748 return file
->f_op
->mmap(file
, vma
);
1751 ssize_t
rw_copy_check_uvector(int type
, const struct iovec __user
* uvector
,
1752 unsigned long nr_segs
, unsigned long fast_segs
,
1753 struct iovec
*fast_pointer
,
1754 struct iovec
**ret_pointer
);
1756 extern ssize_t
__vfs_read(struct file
*, char __user
*, size_t, loff_t
*);
1757 extern ssize_t
__vfs_write(struct file
*, const char __user
*, size_t, loff_t
*);
1758 extern ssize_t
vfs_read(struct file
*, char __user
*, size_t, loff_t
*);
1759 extern ssize_t
vfs_write(struct file
*, const char __user
*, size_t, loff_t
*);
1760 extern ssize_t
vfs_readv(struct file
*, const struct iovec __user
*,
1761 unsigned long, loff_t
*, rwf_t
);
1762 extern ssize_t
vfs_writev(struct file
*, const struct iovec __user
*,
1763 unsigned long, loff_t
*, rwf_t
);
1764 extern ssize_t
vfs_copy_file_range(struct file
*, loff_t
, struct file
*,
1765 loff_t
, size_t, unsigned int);
1766 extern int vfs_clone_file_prep_inodes(struct inode
*inode_in
, loff_t pos_in
,
1767 struct inode
*inode_out
, loff_t pos_out
,
1768 u64
*len
, bool is_dedupe
);
1769 extern int vfs_clone_file_range(struct file
*file_in
, loff_t pos_in
,
1770 struct file
*file_out
, loff_t pos_out
, u64 len
);
1771 extern int vfs_dedupe_file_range_compare(struct inode
*src
, loff_t srcoff
,
1772 struct inode
*dest
, loff_t destoff
,
1773 loff_t len
, bool *is_same
);
1774 extern int vfs_dedupe_file_range(struct file
*file
,
1775 struct file_dedupe_range
*same
);
1777 struct super_operations
{
1778 struct inode
*(*alloc_inode
)(struct super_block
*sb
);
1779 void (*destroy_inode
)(struct inode
*);
1781 void (*dirty_inode
) (struct inode
*, int flags
);
1782 int (*write_inode
) (struct inode
*, struct writeback_control
*wbc
);
1783 int (*drop_inode
) (struct inode
*);
1784 void (*evict_inode
) (struct inode
*);
1785 void (*put_super
) (struct super_block
*);
1786 int (*sync_fs
)(struct super_block
*sb
, int wait
);
1787 int (*freeze_super
) (struct super_block
*);
1788 int (*freeze_fs
) (struct super_block
*);
1789 int (*thaw_super
) (struct super_block
*);
1790 int (*unfreeze_fs
) (struct super_block
*);
1791 int (*statfs
) (struct dentry
*, struct kstatfs
*);
1792 int (*remount_fs
) (struct super_block
*, int *, char *);
1793 void (*umount_begin
) (struct super_block
*);
1795 int (*show_options
)(struct seq_file
*, struct dentry
*);
1796 int (*show_devname
)(struct seq_file
*, struct dentry
*);
1797 int (*show_path
)(struct seq_file
*, struct dentry
*);
1798 int (*show_stats
)(struct seq_file
*, struct dentry
*);
1800 ssize_t (*quota_read
)(struct super_block
*, int, char *, size_t, loff_t
);
1801 ssize_t (*quota_write
)(struct super_block
*, int, const char *, size_t, loff_t
);
1802 struct dquot
**(*get_dquots
)(struct inode
*);
1804 int (*bdev_try_to_free_page
)(struct super_block
*, struct page
*, gfp_t
);
1805 long (*nr_cached_objects
)(struct super_block
*,
1806 struct shrink_control
*);
1807 long (*free_cached_objects
)(struct super_block
*,
1808 struct shrink_control
*);
1812 * Inode flags - they have no relation to superblock flags now
1814 #define S_SYNC 1 /* Writes are synced at once */
1815 #define S_NOATIME 2 /* Do not update access times */
1816 #define S_APPEND 4 /* Append-only file */
1817 #define S_IMMUTABLE 8 /* Immutable file */
1818 #define S_DEAD 16 /* removed, but still open directory */
1819 #define S_NOQUOTA 32 /* Inode is not counted to quota */
1820 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
1821 #define S_NOCMTIME 128 /* Do not update file c/mtime */
1822 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
1823 #define S_PRIVATE 512 /* Inode is fs-internal */
1824 #define S_IMA 1024 /* Inode has an associated IMA struct */
1825 #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
1826 #define S_NOSEC 4096 /* no suid or xattr security attributes */
1827 #ifdef CONFIG_FS_DAX
1828 #define S_DAX 8192 /* Direct Access, avoiding the page cache */
1830 #define S_DAX 0 /* Make all the DAX code disappear */
1834 * Note that nosuid etc flags are inode-specific: setting some file-system
1835 * flags just means all the inodes inherit those flags by default. It might be
1836 * possible to override it selectively if you really wanted to with some
1837 * ioctl() that is not currently implemented.
1839 * Exception: MS_RDONLY is always applied to the entire file system.
1841 * Unfortunately, it is possible to change a filesystems flags with it mounted
1842 * with files in use. This means that all of the inodes will not have their
1843 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1844 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1846 #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1848 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
1849 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
1850 ((inode)->i_flags & S_SYNC))
1851 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
1852 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1853 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
1854 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
1855 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
1857 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1858 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1859 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1860 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
1862 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1863 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1864 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1865 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1866 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1867 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1868 #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
1869 #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
1871 #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
1872 (inode)->i_rdev == WHITEOUT_DEV)
1874 static inline bool HAS_UNMAPPED_ID(struct inode
*inode
)
1876 return !uid_valid(inode
->i_uid
) || !gid_valid(inode
->i_gid
);
1879 static inline enum rw_hint
file_write_hint(struct file
*file
)
1881 if (file
->f_write_hint
!= WRITE_LIFE_NOT_SET
)
1882 return file
->f_write_hint
;
1884 return file_inode(file
)->i_write_hint
;
1887 static inline int iocb_flags(struct file
*file
);
1889 static inline void init_sync_kiocb(struct kiocb
*kiocb
, struct file
*filp
)
1891 *kiocb
= (struct kiocb
) {
1893 .ki_flags
= iocb_flags(filp
),
1894 .ki_hint
= file_write_hint(filp
),
1899 * Inode state bits. Protected by inode->i_lock
1901 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
1902 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
1904 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
1905 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
1906 * various stages of removing an inode.
1908 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
1910 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
1911 * fdatasync(). i_atime is the usual cause.
1912 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
1913 * these changes separately from I_DIRTY_SYNC so that we
1914 * don't have to write inode on fdatasync() when only
1915 * mtime has changed in it.
1916 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
1917 * I_NEW Serves as both a mutex and completion notification.
1918 * New inodes set I_NEW. If two processes both create
1919 * the same inode, one of them will release its inode and
1920 * wait for I_NEW to be released before returning.
1921 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
1922 * also cause waiting on I_NEW, without I_NEW actually
1923 * being set. find_inode() uses this to prevent returning
1924 * nearly-dead inodes.
1925 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
1926 * is zero. I_FREEING must be set when I_WILL_FREE is
1928 * I_FREEING Set when inode is about to be freed but still has dirty
1929 * pages or buffers attached or the inode itself is still
1931 * I_CLEAR Added by clear_inode(). In this state the inode is
1932 * clean and can be destroyed. Inode keeps I_FREEING.
1934 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
1935 * prohibited for many purposes. iget() must wait for
1936 * the inode to be completely released, then create it
1937 * anew. Other functions will just ignore such inodes,
1938 * if appropriate. I_NEW is used for waiting.
1940 * I_SYNC Writeback of inode is running. The bit is set during
1941 * data writeback, and cleared with a wakeup on the bit
1942 * address once it is done. The bit is also used to pin
1943 * the inode in memory for flusher thread.
1945 * I_REFERENCED Marks the inode as recently references on the LRU list.
1947 * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
1949 * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
1950 * synchronize competing switching instances and to tell
1951 * wb stat updates to grab mapping->tree_lock. See
1952 * inode_switch_wb_work_fn() for details.
1954 * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
1955 * and work dirs among overlayfs mounts.
1957 * Q: What is the difference between I_WILL_FREE and I_FREEING?
1959 #define I_DIRTY_SYNC (1 << 0)
1960 #define I_DIRTY_DATASYNC (1 << 1)
1961 #define I_DIRTY_PAGES (1 << 2)
1963 #define I_NEW (1 << __I_NEW)
1964 #define I_WILL_FREE (1 << 4)
1965 #define I_FREEING (1 << 5)
1966 #define I_CLEAR (1 << 6)
1968 #define I_SYNC (1 << __I_SYNC)
1969 #define I_REFERENCED (1 << 8)
1970 #define __I_DIO_WAKEUP 9
1971 #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
1972 #define I_LINKABLE (1 << 10)
1973 #define I_DIRTY_TIME (1 << 11)
1974 #define __I_DIRTY_TIME_EXPIRED 12
1975 #define I_DIRTY_TIME_EXPIRED (1 << __I_DIRTY_TIME_EXPIRED)
1976 #define I_WB_SWITCH (1 << 13)
1977 #define I_OVL_INUSE (1 << 14)
1979 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1980 #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
1982 extern void __mark_inode_dirty(struct inode
*, int);
1983 static inline void mark_inode_dirty(struct inode
*inode
)
1985 __mark_inode_dirty(inode
, I_DIRTY
);
1988 static inline void mark_inode_dirty_sync(struct inode
*inode
)
1990 __mark_inode_dirty(inode
, I_DIRTY_SYNC
);
1993 extern void inc_nlink(struct inode
*inode
);
1994 extern void drop_nlink(struct inode
*inode
);
1995 extern void clear_nlink(struct inode
*inode
);
1996 extern void set_nlink(struct inode
*inode
, unsigned int nlink
);
1998 static inline void inode_inc_link_count(struct inode
*inode
)
2001 mark_inode_dirty(inode
);
2004 static inline void inode_dec_link_count(struct inode
*inode
)
2007 mark_inode_dirty(inode
);
2011 * inode_inc_iversion - increments i_version
2012 * @inode: inode that need to be updated
2014 * Every time the inode is modified, the i_version field will be incremented.
2015 * The filesystem has to be mounted with i_version flag
2018 static inline void inode_inc_iversion(struct inode
*inode
)
2020 spin_lock(&inode
->i_lock
);
2022 spin_unlock(&inode
->i_lock
);
2025 enum file_time_flags
{
2032 extern void touch_atime(const struct path
*);
2033 static inline void file_accessed(struct file
*file
)
2035 if (!(file
->f_flags
& O_NOATIME
))
2036 touch_atime(&file
->f_path
);
2039 int sync_inode(struct inode
*inode
, struct writeback_control
*wbc
);
2040 int sync_inode_metadata(struct inode
*inode
, int wait
);
2042 struct file_system_type
{
2045 #define FS_REQUIRES_DEV 1
2046 #define FS_BINARY_MOUNTDATA 2
2047 #define FS_HAS_SUBTYPE 4
2048 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2049 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2050 struct dentry
*(*mount
) (struct file_system_type
*, int,
2051 const char *, void *);
2052 void (*kill_sb
) (struct super_block
*);
2053 struct module
*owner
;
2054 struct file_system_type
* next
;
2055 struct hlist_head fs_supers
;
2057 struct lock_class_key s_lock_key
;
2058 struct lock_class_key s_umount_key
;
2059 struct lock_class_key s_vfs_rename_key
;
2060 struct lock_class_key s_writers_key
[SB_FREEZE_LEVELS
];
2062 struct lock_class_key i_lock_key
;
2063 struct lock_class_key i_mutex_key
;
2064 struct lock_class_key i_mutex_dir_key
;
2067 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2069 extern struct dentry
*mount_ns(struct file_system_type
*fs_type
,
2070 int flags
, void *data
, void *ns
, struct user_namespace
*user_ns
,
2071 int (*fill_super
)(struct super_block
*, void *, int));
2072 extern struct dentry
*mount_bdev(struct file_system_type
*fs_type
,
2073 int flags
, const char *dev_name
, void *data
,
2074 int (*fill_super
)(struct super_block
*, void *, int));
2075 extern struct dentry
*mount_single(struct file_system_type
*fs_type
,
2076 int flags
, void *data
,
2077 int (*fill_super
)(struct super_block
*, void *, int));
2078 extern struct dentry
*mount_nodev(struct file_system_type
*fs_type
,
2079 int flags
, void *data
,
2080 int (*fill_super
)(struct super_block
*, void *, int));
2081 extern struct dentry
*mount_subtree(struct vfsmount
*mnt
, const char *path
);
2082 void generic_shutdown_super(struct super_block
*sb
);
2083 void kill_block_super(struct super_block
*sb
);
2084 void kill_anon_super(struct super_block
*sb
);
2085 void kill_litter_super(struct super_block
*sb
);
2086 void deactivate_super(struct super_block
*sb
);
2087 void deactivate_locked_super(struct super_block
*sb
);
2088 int set_anon_super(struct super_block
*s
, void *data
);
2089 int get_anon_bdev(dev_t
*);
2090 void free_anon_bdev(dev_t
);
2091 struct super_block
*sget_userns(struct file_system_type
*type
,
2092 int (*test
)(struct super_block
*,void *),
2093 int (*set
)(struct super_block
*,void *),
2094 int flags
, struct user_namespace
*user_ns
,
2096 struct super_block
*sget(struct file_system_type
*type
,
2097 int (*test
)(struct super_block
*,void *),
2098 int (*set
)(struct super_block
*,void *),
2099 int flags
, void *data
);
2100 extern struct dentry
*mount_pseudo_xattr(struct file_system_type
*, char *,
2101 const struct super_operations
*ops
,
2102 const struct xattr_handler
**xattr
,
2103 const struct dentry_operations
*dops
,
2106 static inline struct dentry
*
2107 mount_pseudo(struct file_system_type
*fs_type
, char *name
,
2108 const struct super_operations
*ops
,
2109 const struct dentry_operations
*dops
, unsigned long magic
)
2111 return mount_pseudo_xattr(fs_type
, name
, ops
, NULL
, dops
, magic
);
2114 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2115 #define fops_get(fops) \
2116 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2117 #define fops_put(fops) \
2118 do { if (fops) module_put((fops)->owner); } while(0)
2120 * This one is to be used *ONLY* from ->open() instances.
2121 * fops must be non-NULL, pinned down *and* module dependencies
2122 * should be sufficient to pin the caller down as well.
2124 #define replace_fops(f, fops) \
2126 struct file *__file = (f); \
2127 fops_put(__file->f_op); \
2128 BUG_ON(!(__file->f_op = (fops))); \
2131 extern int register_filesystem(struct file_system_type
*);
2132 extern int unregister_filesystem(struct file_system_type
*);
2133 extern struct vfsmount
*kern_mount_data(struct file_system_type
*, void *data
);
2134 #define kern_mount(type) kern_mount_data(type, NULL)
2135 extern void kern_unmount(struct vfsmount
*mnt
);
2136 extern int may_umount_tree(struct vfsmount
*);
2137 extern int may_umount(struct vfsmount
*);
2138 extern long do_mount(const char *, const char __user
*,
2139 const char *, unsigned long, void *);
2140 extern struct vfsmount
*collect_mounts(const struct path
*);
2141 extern void drop_collected_mounts(struct vfsmount
*);
2142 extern int iterate_mounts(int (*)(struct vfsmount
*, void *), void *,
2144 extern int vfs_statfs(const struct path
*, struct kstatfs
*);
2145 extern int user_statfs(const char __user
*, struct kstatfs
*);
2146 extern int fd_statfs(int, struct kstatfs
*);
2147 extern int vfs_ustat(dev_t
, struct kstatfs
*);
2148 extern int freeze_super(struct super_block
*super
);
2149 extern int thaw_super(struct super_block
*super
);
2150 extern bool our_mnt(struct vfsmount
*mnt
);
2151 extern __printf(2, 3)
2152 int super_setup_bdi_name(struct super_block
*sb
, char *fmt
, ...);
2153 extern int super_setup_bdi(struct super_block
*sb
);
2155 extern int current_umask(void);
2157 extern void ihold(struct inode
* inode
);
2158 extern void iput(struct inode
*);
2159 extern int generic_update_time(struct inode
*, struct timespec
*, int);
2162 extern struct kobject
*fs_kobj
;
2164 #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2166 #ifdef CONFIG_MANDATORY_FILE_LOCKING
2167 extern int locks_mandatory_locked(struct file
*);
2168 extern int locks_mandatory_area(struct inode
*, struct file
*, loff_t
, loff_t
, unsigned char);
2171 * Candidates for mandatory locking have the setgid bit set
2172 * but no group execute bit - an otherwise meaningless combination.
2175 static inline int __mandatory_lock(struct inode
*ino
)
2177 return (ino
->i_mode
& (S_ISGID
| S_IXGRP
)) == S_ISGID
;
2181 * ... and these candidates should be on MS_MANDLOCK mounted fs,
2182 * otherwise these will be advisory locks
2185 static inline int mandatory_lock(struct inode
*ino
)
2187 return IS_MANDLOCK(ino
) && __mandatory_lock(ino
);
2190 static inline int locks_verify_locked(struct file
*file
)
2192 if (mandatory_lock(locks_inode(file
)))
2193 return locks_mandatory_locked(file
);
2197 static inline int locks_verify_truncate(struct inode
*inode
,
2201 if (!inode
->i_flctx
|| !mandatory_lock(inode
))
2204 if (size
< inode
->i_size
) {
2205 return locks_mandatory_area(inode
, f
, size
, inode
->i_size
- 1,
2208 return locks_mandatory_area(inode
, f
, inode
->i_size
, size
- 1,
2213 #else /* !CONFIG_MANDATORY_FILE_LOCKING */
2215 static inline int locks_mandatory_locked(struct file
*file
)
2220 static inline int locks_mandatory_area(struct inode
*inode
, struct file
*filp
,
2221 loff_t start
, loff_t end
, unsigned char type
)
2226 static inline int __mandatory_lock(struct inode
*inode
)
2231 static inline int mandatory_lock(struct inode
*inode
)
2236 static inline int locks_verify_locked(struct file
*file
)
2241 static inline int locks_verify_truncate(struct inode
*inode
, struct file
*filp
,
2247 #endif /* CONFIG_MANDATORY_FILE_LOCKING */
2250 #ifdef CONFIG_FILE_LOCKING
2251 static inline int break_lease(struct inode
*inode
, unsigned int mode
)
2254 * Since this check is lockless, we must ensure that any refcounts
2255 * taken are done before checking i_flctx->flc_lease. Otherwise, we
2256 * could end up racing with tasks trying to set a new lease on this
2260 if (inode
->i_flctx
&& !list_empty_careful(&inode
->i_flctx
->flc_lease
))
2261 return __break_lease(inode
, mode
, FL_LEASE
);
2265 static inline int break_deleg(struct inode
*inode
, unsigned int mode
)
2268 * Since this check is lockless, we must ensure that any refcounts
2269 * taken are done before checking i_flctx->flc_lease. Otherwise, we
2270 * could end up racing with tasks trying to set a new lease on this
2274 if (inode
->i_flctx
&& !list_empty_careful(&inode
->i_flctx
->flc_lease
))
2275 return __break_lease(inode
, mode
, FL_DELEG
);
2279 static inline int try_break_deleg(struct inode
*inode
, struct inode
**delegated_inode
)
2283 ret
= break_deleg(inode
, O_WRONLY
|O_NONBLOCK
);
2284 if (ret
== -EWOULDBLOCK
&& delegated_inode
) {
2285 *delegated_inode
= inode
;
2291 static inline int break_deleg_wait(struct inode
**delegated_inode
)
2295 ret
= break_deleg(*delegated_inode
, O_WRONLY
);
2296 iput(*delegated_inode
);
2297 *delegated_inode
= NULL
;
2301 static inline int break_layout(struct inode
*inode
, bool wait
)
2304 if (inode
->i_flctx
&& !list_empty_careful(&inode
->i_flctx
->flc_lease
))
2305 return __break_lease(inode
,
2306 wait
? O_WRONLY
: O_WRONLY
| O_NONBLOCK
,
2311 #else /* !CONFIG_FILE_LOCKING */
2312 static inline int break_lease(struct inode
*inode
, unsigned int mode
)
2317 static inline int break_deleg(struct inode
*inode
, unsigned int mode
)
2322 static inline int try_break_deleg(struct inode
*inode
, struct inode
**delegated_inode
)
2327 static inline int break_deleg_wait(struct inode
**delegated_inode
)
2333 static inline int break_layout(struct inode
*inode
, bool wait
)
2338 #endif /* CONFIG_FILE_LOCKING */
2343 const char *name
; /* pointer to actual string */
2344 const __user
char *uptr
; /* original userland pointer */
2345 struct audit_names
*aname
;
2350 extern long vfs_truncate(const struct path
*, loff_t
);
2351 extern int do_truncate(struct dentry
*, loff_t start
, unsigned int time_attrs
,
2353 extern int vfs_fallocate(struct file
*file
, int mode
, loff_t offset
,
2355 extern long do_sys_open(int dfd
, const char __user
*filename
, int flags
,
2357 extern struct file
*file_open_name(struct filename
*, int, umode_t
);
2358 extern struct file
*filp_open(const char *, int, umode_t
);
2359 extern struct file
*file_open_root(struct dentry
*, struct vfsmount
*,
2360 const char *, int, umode_t
);
2361 extern struct file
* dentry_open(const struct path
*, int, const struct cred
*);
2362 extern int filp_close(struct file
*, fl_owner_t id
);
2364 extern struct filename
*getname_flags(const char __user
*, int, int *);
2365 extern struct filename
*getname(const char __user
*);
2366 extern struct filename
*getname_kernel(const char *);
2367 extern void putname(struct filename
*name
);
2373 extern int finish_open(struct file
*file
, struct dentry
*dentry
,
2374 int (*open
)(struct inode
*, struct file
*),
2376 extern int finish_no_open(struct file
*file
, struct dentry
*dentry
);
2380 extern int ioctl_preallocate(struct file
*filp
, void __user
*argp
);
2383 extern void __init
vfs_caches_init_early(void);
2384 extern void __init
vfs_caches_init(void);
2386 extern struct kmem_cache
*names_cachep
;
2388 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2389 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2392 extern int register_blkdev(unsigned int, const char *);
2393 extern void unregister_blkdev(unsigned int, const char *);
2394 extern void bdev_unhash_inode(dev_t dev
);
2395 extern struct block_device
*bdget(dev_t
);
2396 extern struct block_device
*bdgrab(struct block_device
*bdev
);
2397 extern void bd_set_size(struct block_device
*, loff_t size
);
2398 extern void bd_forget(struct inode
*inode
);
2399 extern void bdput(struct block_device
*);
2400 extern void invalidate_bdev(struct block_device
*);
2401 extern void iterate_bdevs(void (*)(struct block_device
*, void *), void *);
2402 extern int sync_blockdev(struct block_device
*bdev
);
2403 extern void kill_bdev(struct block_device
*);
2404 extern struct super_block
*freeze_bdev(struct block_device
*);
2405 extern void emergency_thaw_all(void);
2406 extern int thaw_bdev(struct block_device
*bdev
, struct super_block
*sb
);
2407 extern int fsync_bdev(struct block_device
*);
2409 extern struct super_block
*blockdev_superblock
;
2411 static inline bool sb_is_blkdev_sb(struct super_block
*sb
)
2413 return sb
== blockdev_superblock
;
2416 static inline void bd_forget(struct inode
*inode
) {}
2417 static inline int sync_blockdev(struct block_device
*bdev
) { return 0; }
2418 static inline void kill_bdev(struct block_device
*bdev
) {}
2419 static inline void invalidate_bdev(struct block_device
*bdev
) {}
2421 static inline struct super_block
*freeze_bdev(struct block_device
*sb
)
2426 static inline int thaw_bdev(struct block_device
*bdev
, struct super_block
*sb
)
2431 static inline void iterate_bdevs(void (*f
)(struct block_device
*, void *), void *arg
)
2435 static inline bool sb_is_blkdev_sb(struct super_block
*sb
)
2440 extern int sync_filesystem(struct super_block
*);
2441 extern const struct file_operations def_blk_fops
;
2442 extern const struct file_operations def_chr_fops
;
2444 extern int ioctl_by_bdev(struct block_device
*, unsigned, unsigned long);
2445 extern int blkdev_ioctl(struct block_device
*, fmode_t
, unsigned, unsigned long);
2446 extern long compat_blkdev_ioctl(struct file
*, unsigned, unsigned long);
2447 extern int blkdev_get(struct block_device
*bdev
, fmode_t mode
, void *holder
);
2448 extern struct block_device
*blkdev_get_by_path(const char *path
, fmode_t mode
,
2450 extern struct block_device
*blkdev_get_by_dev(dev_t dev
, fmode_t mode
,
2452 extern void blkdev_put(struct block_device
*bdev
, fmode_t mode
);
2453 extern int __blkdev_reread_part(struct block_device
*bdev
);
2454 extern int blkdev_reread_part(struct block_device
*bdev
);
2457 extern int bd_link_disk_holder(struct block_device
*bdev
, struct gendisk
*disk
);
2458 extern void bd_unlink_disk_holder(struct block_device
*bdev
,
2459 struct gendisk
*disk
);
2461 static inline int bd_link_disk_holder(struct block_device
*bdev
,
2462 struct gendisk
*disk
)
2466 static inline void bd_unlink_disk_holder(struct block_device
*bdev
,
2467 struct gendisk
*disk
)
2474 #define CHRDEV_MAJOR_MAX 512
2475 /* Marks the bottom of the first segment of free char majors */
2476 #define CHRDEV_MAJOR_DYN_END 234
2477 /* Marks the top and bottom of the second segment of free char majors */
2478 #define CHRDEV_MAJOR_DYN_EXT_START 511
2479 #define CHRDEV_MAJOR_DYN_EXT_END 384
2481 extern int alloc_chrdev_region(dev_t
*, unsigned, unsigned, const char *);
2482 extern int register_chrdev_region(dev_t
, unsigned, const char *);
2483 extern int __register_chrdev(unsigned int major
, unsigned int baseminor
,
2484 unsigned int count
, const char *name
,
2485 const struct file_operations
*fops
);
2486 extern void __unregister_chrdev(unsigned int major
, unsigned int baseminor
,
2487 unsigned int count
, const char *name
);
2488 extern void unregister_chrdev_region(dev_t
, unsigned);
2489 extern void chrdev_show(struct seq_file
*,off_t
);
2491 static inline int register_chrdev(unsigned int major
, const char *name
,
2492 const struct file_operations
*fops
)
2494 return __register_chrdev(major
, 0, 256, name
, fops
);
2497 static inline void unregister_chrdev(unsigned int major
, const char *name
)
2499 __unregister_chrdev(major
, 0, 256, name
);
2502 /* fs/block_dev.c */
2503 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
2504 #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
2507 #define BLKDEV_MAJOR_MAX 512
2508 extern const char *__bdevname(dev_t
, char *buffer
);
2509 extern const char *bdevname(struct block_device
*bdev
, char *buffer
);
2510 extern struct block_device
*lookup_bdev(const char *);
2511 extern void blkdev_show(struct seq_file
*,off_t
);
2514 #define BLKDEV_MAJOR_MAX 0
2517 extern void init_special_inode(struct inode
*, umode_t
, dev_t
);
2519 /* Invalid inode operations -- fs/bad_inode.c */
2520 extern void make_bad_inode(struct inode
*);
2521 extern bool is_bad_inode(struct inode
*);
2524 extern void check_disk_size_change(struct gendisk
*disk
,
2525 struct block_device
*bdev
);
2526 extern int revalidate_disk(struct gendisk
*);
2527 extern int check_disk_change(struct block_device
*);
2528 extern int __invalidate_device(struct block_device
*, bool);
2529 extern int invalidate_partition(struct gendisk
*, int);
2531 unsigned long invalidate_mapping_pages(struct address_space
*mapping
,
2532 pgoff_t start
, pgoff_t end
);
2534 static inline void invalidate_remote_inode(struct inode
*inode
)
2536 if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
2537 S_ISLNK(inode
->i_mode
))
2538 invalidate_mapping_pages(inode
->i_mapping
, 0, -1);
2540 extern int invalidate_inode_pages2(struct address_space
*mapping
);
2541 extern int invalidate_inode_pages2_range(struct address_space
*mapping
,
2542 pgoff_t start
, pgoff_t end
);
2543 extern int write_inode_now(struct inode
*, int);
2544 extern int filemap_fdatawrite(struct address_space
*);
2545 extern int filemap_flush(struct address_space
*);
2546 extern int filemap_fdatawait_keep_errors(struct address_space
*mapping
);
2547 extern int filemap_fdatawait_range(struct address_space
*, loff_t lstart
,
2550 static inline int filemap_fdatawait(struct address_space
*mapping
)
2552 return filemap_fdatawait_range(mapping
, 0, LLONG_MAX
);
2555 extern bool filemap_range_has_page(struct address_space
*, loff_t lstart
,
2557 extern int __must_check
file_fdatawait_range(struct file
*file
, loff_t lstart
,
2559 extern int filemap_write_and_wait(struct address_space
*mapping
);
2560 extern int filemap_write_and_wait_range(struct address_space
*mapping
,
2561 loff_t lstart
, loff_t lend
);
2562 extern int __filemap_fdatawrite_range(struct address_space
*mapping
,
2563 loff_t start
, loff_t end
, int sync_mode
);
2564 extern int filemap_fdatawrite_range(struct address_space
*mapping
,
2565 loff_t start
, loff_t end
);
2566 extern int filemap_check_errors(struct address_space
*mapping
);
2567 extern void __filemap_set_wb_err(struct address_space
*mapping
, int err
);
2569 extern int __must_check
file_fdatawait_range(struct file
*file
, loff_t lstart
,
2571 extern int __must_check
file_check_and_advance_wb_err(struct file
*file
);
2572 extern int __must_check
file_write_and_wait_range(struct file
*file
,
2573 loff_t start
, loff_t end
);
2575 static inline int file_write_and_wait(struct file
*file
)
2577 return file_write_and_wait_range(file
, 0, LLONG_MAX
);
2581 * filemap_set_wb_err - set a writeback error on an address_space
2582 * @mapping: mapping in which to set writeback error
2583 * @err: error to be set in mapping
2585 * When writeback fails in some way, we must record that error so that
2586 * userspace can be informed when fsync and the like are called. We endeavor
2587 * to report errors on any file that was open at the time of the error. Some
2588 * internal callers also need to know when writeback errors have occurred.
2590 * When a writeback error occurs, most filesystems will want to call
2591 * filemap_set_wb_err to record the error in the mapping so that it will be
2592 * automatically reported whenever fsync is called on the file.
2594 static inline void filemap_set_wb_err(struct address_space
*mapping
, int err
)
2596 /* Fastpath for common case of no error */
2598 __filemap_set_wb_err(mapping
, err
);
2602 * filemap_check_wb_error - has an error occurred since the mark was sampled?
2603 * @mapping: mapping to check for writeback errors
2604 * @since: previously-sampled errseq_t
2606 * Grab the errseq_t value from the mapping, and see if it has changed "since"
2607 * the given value was sampled.
2609 * If it has then report the latest error set, otherwise return 0.
2611 static inline int filemap_check_wb_err(struct address_space
*mapping
,
2614 return errseq_check(&mapping
->wb_err
, since
);
2618 * filemap_sample_wb_err - sample the current errseq_t to test for later errors
2619 * @mapping: mapping to be sampled
2621 * Writeback errors are always reported relative to a particular sample point
2622 * in the past. This function provides those sample points.
2624 static inline errseq_t
filemap_sample_wb_err(struct address_space
*mapping
)
2626 return errseq_sample(&mapping
->wb_err
);
2629 extern int vfs_fsync_range(struct file
*file
, loff_t start
, loff_t end
,
2631 extern int vfs_fsync(struct file
*file
, int datasync
);
2634 * Sync the bytes written if this was a synchronous write. Expect ki_pos
2635 * to already be updated for the write, and will return either the amount
2636 * of bytes passed in, or an error if syncing the file failed.
2638 static inline ssize_t
generic_write_sync(struct kiocb
*iocb
, ssize_t count
)
2640 if (iocb
->ki_flags
& IOCB_DSYNC
) {
2641 int ret
= vfs_fsync_range(iocb
->ki_filp
,
2642 iocb
->ki_pos
- count
, iocb
->ki_pos
- 1,
2643 (iocb
->ki_flags
& IOCB_SYNC
) ? 0 : 1);
2651 extern void emergency_sync(void);
2652 extern void emergency_remount(void);
2654 extern sector_t
bmap(struct inode
*, sector_t
);
2656 extern int notify_change(struct dentry
*, struct iattr
*, struct inode
**);
2657 extern int inode_permission(struct inode
*, int);
2658 extern int __inode_permission(struct inode
*, int);
2659 extern int generic_permission(struct inode
*, int);
2660 extern int __check_sticky(struct inode
*dir
, struct inode
*inode
);
2662 static inline bool execute_ok(struct inode
*inode
)
2664 return (inode
->i_mode
& S_IXUGO
) || S_ISDIR(inode
->i_mode
);
2667 static inline void file_start_write(struct file
*file
)
2669 if (!S_ISREG(file_inode(file
)->i_mode
))
2671 __sb_start_write(file_inode(file
)->i_sb
, SB_FREEZE_WRITE
, true);
2674 static inline bool file_start_write_trylock(struct file
*file
)
2676 if (!S_ISREG(file_inode(file
)->i_mode
))
2678 return __sb_start_write(file_inode(file
)->i_sb
, SB_FREEZE_WRITE
, false);
2681 static inline void file_end_write(struct file
*file
)
2683 if (!S_ISREG(file_inode(file
)->i_mode
))
2685 __sb_end_write(file_inode(file
)->i_sb
, SB_FREEZE_WRITE
);
2688 static inline int do_clone_file_range(struct file
*file_in
, loff_t pos_in
,
2689 struct file
*file_out
, loff_t pos_out
,
2694 file_start_write(file_out
);
2695 ret
= vfs_clone_file_range(file_in
, pos_in
, file_out
, pos_out
, len
);
2696 file_end_write(file_out
);
2702 * get_write_access() gets write permission for a file.
2703 * put_write_access() releases this write permission.
2704 * This is used for regular files.
2705 * We cannot support write (and maybe mmap read-write shared) accesses and
2706 * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
2707 * can have the following values:
2708 * 0: no writers, no VM_DENYWRITE mappings
2709 * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
2710 * > 0: (i_writecount) users are writing to the file.
2712 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2713 * except for the cases where we don't hold i_writecount yet. Then we need to
2714 * use {get,deny}_write_access() - these functions check the sign and refuse
2715 * to do the change if sign is wrong.
2717 static inline int get_write_access(struct inode
*inode
)
2719 return atomic_inc_unless_negative(&inode
->i_writecount
) ? 0 : -ETXTBSY
;
2721 static inline int deny_write_access(struct file
*file
)
2723 struct inode
*inode
= file_inode(file
);
2724 return atomic_dec_unless_positive(&inode
->i_writecount
) ? 0 : -ETXTBSY
;
2726 static inline void put_write_access(struct inode
* inode
)
2728 atomic_dec(&inode
->i_writecount
);
2730 static inline void allow_write_access(struct file
*file
)
2733 atomic_inc(&file_inode(file
)->i_writecount
);
2735 static inline bool inode_is_open_for_write(const struct inode
*inode
)
2737 return atomic_read(&inode
->i_writecount
) > 0;
2741 static inline void i_readcount_dec(struct inode
*inode
)
2743 BUG_ON(!atomic_read(&inode
->i_readcount
));
2744 atomic_dec(&inode
->i_readcount
);
2746 static inline void i_readcount_inc(struct inode
*inode
)
2748 atomic_inc(&inode
->i_readcount
);
2751 static inline void i_readcount_dec(struct inode
*inode
)
2755 static inline void i_readcount_inc(struct inode
*inode
)
2760 extern int do_pipe_flags(int *, int);
2762 #define __kernel_read_file_id(id) \
2763 id(UNKNOWN, unknown) \
2764 id(FIRMWARE, firmware) \
2765 id(FIRMWARE_PREALLOC_BUFFER, firmware) \
2766 id(MODULE, kernel-module) \
2767 id(KEXEC_IMAGE, kexec-image) \
2768 id(KEXEC_INITRAMFS, kexec-initramfs) \
2769 id(POLICY, security-policy) \
2772 #define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
2773 #define __fid_stringify(dummy, str) #str,
2775 enum kernel_read_file_id
{
2776 __kernel_read_file_id(__fid_enumify
)
2779 static const char * const kernel_read_file_str
[] = {
2780 __kernel_read_file_id(__fid_stringify
)
2783 static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id
)
2785 if ((unsigned)id
>= READING_MAX_ID
)
2786 return kernel_read_file_str
[READING_UNKNOWN
];
2788 return kernel_read_file_str
[id
];
2791 extern int kernel_read(struct file
*, loff_t
, char *, unsigned long);
2792 extern int kernel_read_file(struct file
*, void **, loff_t
*, loff_t
,
2793 enum kernel_read_file_id
);
2794 extern int kernel_read_file_from_path(char *, void **, loff_t
*, loff_t
,
2795 enum kernel_read_file_id
);
2796 extern int kernel_read_file_from_fd(int, void **, loff_t
*, loff_t
,
2797 enum kernel_read_file_id
);
2798 extern ssize_t
kernel_write(struct file
*, const char *, size_t, loff_t
);
2799 extern ssize_t
__kernel_write(struct file
*, const char *, size_t, loff_t
*);
2800 extern struct file
* open_exec(const char *);
2802 /* fs/dcache.c -- generic fs support functions */
2803 extern bool is_subdir(struct dentry
*, struct dentry
*);
2804 extern bool path_is_under(const struct path
*, const struct path
*);
2806 extern char *file_path(struct file
*, char *, int);
2808 #include <linux/err.h>
2810 /* needed for stackable file system support */
2811 extern loff_t
default_llseek(struct file
*file
, loff_t offset
, int whence
);
2813 extern loff_t
vfs_llseek(struct file
*file
, loff_t offset
, int whence
);
2815 extern int inode_init_always(struct super_block
*, struct inode
*);
2816 extern void inode_init_once(struct inode
*);
2817 extern void address_space_init_once(struct address_space
*mapping
);
2818 extern struct inode
* igrab(struct inode
*);
2819 extern ino_t
iunique(struct super_block
*, ino_t
);
2820 extern int inode_needs_sync(struct inode
*inode
);
2821 extern int generic_delete_inode(struct inode
*inode
);
2822 static inline int generic_drop_inode(struct inode
*inode
)
2824 return !inode
->i_nlink
|| inode_unhashed(inode
);
2827 extern struct inode
*ilookup5_nowait(struct super_block
*sb
,
2828 unsigned long hashval
, int (*test
)(struct inode
*, void *),
2830 extern struct inode
*ilookup5(struct super_block
*sb
, unsigned long hashval
,
2831 int (*test
)(struct inode
*, void *), void *data
);
2832 extern struct inode
*ilookup(struct super_block
*sb
, unsigned long ino
);
2834 extern struct inode
* iget5_locked(struct super_block
*, unsigned long, int (*test
)(struct inode
*, void *), int (*set
)(struct inode
*, void *), void *);
2835 extern struct inode
* iget_locked(struct super_block
*, unsigned long);
2836 extern struct inode
*find_inode_nowait(struct super_block
*,
2838 int (*match
)(struct inode
*,
2839 unsigned long, void *),
2841 extern int insert_inode_locked4(struct inode
*, unsigned long, int (*test
)(struct inode
*, void *), void *);
2842 extern int insert_inode_locked(struct inode
*);
2843 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2844 extern void lockdep_annotate_inode_mutex_key(struct inode
*inode
);
2846 static inline void lockdep_annotate_inode_mutex_key(struct inode
*inode
) { };
2848 extern void unlock_new_inode(struct inode
*);
2849 extern unsigned int get_next_ino(void);
2850 extern void evict_inodes(struct super_block
*sb
);
2852 extern void __iget(struct inode
* inode
);
2853 extern void iget_failed(struct inode
*);
2854 extern void clear_inode(struct inode
*);
2855 extern void __destroy_inode(struct inode
*);
2856 extern struct inode
*new_inode_pseudo(struct super_block
*sb
);
2857 extern struct inode
*new_inode(struct super_block
*sb
);
2858 extern void free_inode_nonrcu(struct inode
*inode
);
2859 extern int should_remove_suid(struct dentry
*);
2860 extern int file_remove_privs(struct file
*);
2862 extern void __insert_inode_hash(struct inode
*, unsigned long hashval
);
2863 static inline void insert_inode_hash(struct inode
*inode
)
2865 __insert_inode_hash(inode
, inode
->i_ino
);
2868 extern void __remove_inode_hash(struct inode
*);
2869 static inline void remove_inode_hash(struct inode
*inode
)
2871 if (!inode_unhashed(inode
) && !hlist_fake(&inode
->i_hash
))
2872 __remove_inode_hash(inode
);
2875 extern void inode_sb_list_add(struct inode
*inode
);
2878 extern int bdev_read_only(struct block_device
*);
2880 extern int set_blocksize(struct block_device
*, int);
2881 extern int sb_set_blocksize(struct super_block
*, int);
2882 extern int sb_min_blocksize(struct super_block
*, int);
2884 extern int generic_file_mmap(struct file
*, struct vm_area_struct
*);
2885 extern int generic_file_readonly_mmap(struct file
*, struct vm_area_struct
*);
2886 extern ssize_t
generic_write_checks(struct kiocb
*, struct iov_iter
*);
2887 extern ssize_t
generic_file_read_iter(struct kiocb
*, struct iov_iter
*);
2888 extern ssize_t
__generic_file_write_iter(struct kiocb
*, struct iov_iter
*);
2889 extern ssize_t
generic_file_write_iter(struct kiocb
*, struct iov_iter
*);
2890 extern ssize_t
generic_file_direct_write(struct kiocb
*, struct iov_iter
*);
2891 extern ssize_t
generic_perform_write(struct file
*, struct iov_iter
*, loff_t
);
2893 ssize_t
vfs_iter_read(struct file
*file
, struct iov_iter
*iter
, loff_t
*ppos
,
2895 ssize_t
vfs_iter_write(struct file
*file
, struct iov_iter
*iter
, loff_t
*ppos
,
2898 /* fs/block_dev.c */
2899 extern ssize_t
blkdev_read_iter(struct kiocb
*iocb
, struct iov_iter
*to
);
2900 extern ssize_t
blkdev_write_iter(struct kiocb
*iocb
, struct iov_iter
*from
);
2901 extern int blkdev_fsync(struct file
*filp
, loff_t start
, loff_t end
,
2903 extern void block_sync_page(struct page
*page
);
2906 extern ssize_t
generic_file_splice_read(struct file
*, loff_t
*,
2907 struct pipe_inode_info
*, size_t, unsigned int);
2908 extern ssize_t
iter_file_splice_write(struct pipe_inode_info
*,
2909 struct file
*, loff_t
*, size_t, unsigned int);
2910 extern ssize_t
generic_splice_sendpage(struct pipe_inode_info
*pipe
,
2911 struct file
*out
, loff_t
*, size_t len
, unsigned int flags
);
2912 extern long do_splice_direct(struct file
*in
, loff_t
*ppos
, struct file
*out
,
2913 loff_t
*opos
, size_t len
, unsigned int flags
);
2917 file_ra_state_init(struct file_ra_state
*ra
, struct address_space
*mapping
);
2918 extern loff_t
noop_llseek(struct file
*file
, loff_t offset
, int whence
);
2919 extern loff_t
no_llseek(struct file
*file
, loff_t offset
, int whence
);
2920 extern loff_t
vfs_setpos(struct file
*file
, loff_t offset
, loff_t maxsize
);
2921 extern loff_t
generic_file_llseek(struct file
*file
, loff_t offset
, int whence
);
2922 extern loff_t
generic_file_llseek_size(struct file
*file
, loff_t offset
,
2923 int whence
, loff_t maxsize
, loff_t eof
);
2924 extern loff_t
fixed_size_llseek(struct file
*file
, loff_t offset
,
2925 int whence
, loff_t size
);
2926 extern loff_t
no_seek_end_llseek_size(struct file
*, loff_t
, int, loff_t
);
2927 extern loff_t
no_seek_end_llseek(struct file
*, loff_t
, int);
2928 extern int generic_file_open(struct inode
* inode
, struct file
* filp
);
2929 extern int nonseekable_open(struct inode
* inode
, struct file
* filp
);
2932 typedef void (dio_submit_t
)(struct bio
*bio
, struct inode
*inode
,
2933 loff_t file_offset
);
2936 /* need locking between buffered and direct access */
2939 /* filesystem does not support filling holes */
2940 DIO_SKIP_HOLES
= 0x02,
2942 /* filesystem can handle aio writes beyond i_size */
2943 DIO_ASYNC_EXTEND
= 0x04,
2945 /* inode/fs/bdev does not need truncate protection */
2946 DIO_SKIP_DIO_COUNT
= 0x08,
2949 void dio_end_io(struct bio
*bio
);
2951 ssize_t
__blockdev_direct_IO(struct kiocb
*iocb
, struct inode
*inode
,
2952 struct block_device
*bdev
, struct iov_iter
*iter
,
2953 get_block_t get_block
,
2954 dio_iodone_t end_io
, dio_submit_t submit_io
,
2957 static inline ssize_t
blockdev_direct_IO(struct kiocb
*iocb
,
2958 struct inode
*inode
,
2959 struct iov_iter
*iter
,
2960 get_block_t get_block
)
2962 return __blockdev_direct_IO(iocb
, inode
, inode
->i_sb
->s_bdev
, iter
,
2963 get_block
, NULL
, NULL
, DIO_LOCKING
| DIO_SKIP_HOLES
);
2967 void inode_dio_wait(struct inode
*inode
);
2970 * inode_dio_begin - signal start of a direct I/O requests
2971 * @inode: inode the direct I/O happens on
2973 * This is called once we've finished processing a direct I/O request,
2974 * and is used to wake up callers waiting for direct I/O to be quiesced.
2976 static inline void inode_dio_begin(struct inode
*inode
)
2978 atomic_inc(&inode
->i_dio_count
);
2982 * inode_dio_end - signal finish of a direct I/O requests
2983 * @inode: inode the direct I/O happens on
2985 * This is called once we've finished processing a direct I/O request,
2986 * and is used to wake up callers waiting for direct I/O to be quiesced.
2988 static inline void inode_dio_end(struct inode
*inode
)
2990 if (atomic_dec_and_test(&inode
->i_dio_count
))
2991 wake_up_bit(&inode
->i_state
, __I_DIO_WAKEUP
);
2994 extern void inode_set_flags(struct inode
*inode
, unsigned int flags
,
2997 extern const struct file_operations generic_ro_fops
;
2999 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
3001 extern int readlink_copy(char __user
*, int, const char *);
3002 extern int page_readlink(struct dentry
*, char __user
*, int);
3003 extern const char *page_get_link(struct dentry
*, struct inode
*,
3004 struct delayed_call
*);
3005 extern void page_put_link(void *);
3006 extern int __page_symlink(struct inode
*inode
, const char *symname
, int len
,
3008 extern int page_symlink(struct inode
*inode
, const char *symname
, int len
);
3009 extern const struct inode_operations page_symlink_inode_operations
;
3010 extern void kfree_link(void *);
3011 extern void generic_fillattr(struct inode
*, struct kstat
*);
3012 extern int vfs_getattr_nosec(const struct path
*, struct kstat
*, u32
, unsigned int);
3013 extern int vfs_getattr(const struct path
*, struct kstat
*, u32
, unsigned int);
3014 void __inode_add_bytes(struct inode
*inode
, loff_t bytes
);
3015 void inode_add_bytes(struct inode
*inode
, loff_t bytes
);
3016 void __inode_sub_bytes(struct inode
*inode
, loff_t bytes
);
3017 void inode_sub_bytes(struct inode
*inode
, loff_t bytes
);
3018 static inline loff_t
__inode_get_bytes(struct inode
*inode
)
3020 return (((loff_t
)inode
->i_blocks
) << 9) + inode
->i_bytes
;
3022 loff_t
inode_get_bytes(struct inode
*inode
);
3023 void inode_set_bytes(struct inode
*inode
, loff_t bytes
);
3024 const char *simple_get_link(struct dentry
*, struct inode
*,
3025 struct delayed_call
*);
3026 extern const struct inode_operations simple_symlink_inode_operations
;
3028 extern int iterate_dir(struct file
*, struct dir_context
*);
3030 extern int vfs_statx(int, const char __user
*, int, struct kstat
*, u32
);
3031 extern int vfs_statx_fd(unsigned int, struct kstat
*, u32
, unsigned int);
3033 static inline int vfs_stat(const char __user
*filename
, struct kstat
*stat
)
3035 return vfs_statx(AT_FDCWD
, filename
, AT_NO_AUTOMOUNT
,
3036 stat
, STATX_BASIC_STATS
);
3038 static inline int vfs_lstat(const char __user
*name
, struct kstat
*stat
)
3040 return vfs_statx(AT_FDCWD
, name
, AT_SYMLINK_NOFOLLOW
| AT_NO_AUTOMOUNT
,
3041 stat
, STATX_BASIC_STATS
);
3043 static inline int vfs_fstatat(int dfd
, const char __user
*filename
,
3044 struct kstat
*stat
, int flags
)
3046 return vfs_statx(dfd
, filename
, flags
, stat
, STATX_BASIC_STATS
);
3048 static inline int vfs_fstat(int fd
, struct kstat
*stat
)
3050 return vfs_statx_fd(fd
, stat
, STATX_BASIC_STATS
, 0);
3054 extern const char *vfs_get_link(struct dentry
*, struct delayed_call
*);
3055 extern int vfs_readlink(struct dentry
*, char __user
*, int);
3057 extern int __generic_block_fiemap(struct inode
*inode
,
3058 struct fiemap_extent_info
*fieinfo
,
3059 loff_t start
, loff_t len
,
3060 get_block_t
*get_block
);
3061 extern int generic_block_fiemap(struct inode
*inode
,
3062 struct fiemap_extent_info
*fieinfo
, u64 start
,
3063 u64 len
, get_block_t
*get_block
);
3065 extern struct file_system_type
*get_filesystem(struct file_system_type
*fs
);
3066 extern void put_filesystem(struct file_system_type
*fs
);
3067 extern struct file_system_type
*get_fs_type(const char *name
);
3068 extern struct super_block
*get_super(struct block_device
*);
3069 extern struct super_block
*get_super_thawed(struct block_device
*);
3070 extern struct super_block
*get_super_exclusive_thawed(struct block_device
*bdev
);
3071 extern struct super_block
*get_active_super(struct block_device
*bdev
);
3072 extern void drop_super(struct super_block
*sb
);
3073 extern void drop_super_exclusive(struct super_block
*sb
);
3074 extern void iterate_supers(void (*)(struct super_block
*, void *), void *);
3075 extern void iterate_supers_type(struct file_system_type
*,
3076 void (*)(struct super_block
*, void *), void *);
3078 extern int dcache_dir_open(struct inode
*, struct file
*);
3079 extern int dcache_dir_close(struct inode
*, struct file
*);
3080 extern loff_t
dcache_dir_lseek(struct file
*, loff_t
, int);
3081 extern int dcache_readdir(struct file
*, struct dir_context
*);
3082 extern int simple_setattr(struct dentry
*, struct iattr
*);
3083 extern int simple_getattr(const struct path
*, struct kstat
*, u32
, unsigned int);
3084 extern int simple_statfs(struct dentry
*, struct kstatfs
*);
3085 extern int simple_open(struct inode
*inode
, struct file
*file
);
3086 extern int simple_link(struct dentry
*, struct inode
*, struct dentry
*);
3087 extern int simple_unlink(struct inode
*, struct dentry
*);
3088 extern int simple_rmdir(struct inode
*, struct dentry
*);
3089 extern int simple_rename(struct inode
*, struct dentry
*,
3090 struct inode
*, struct dentry
*, unsigned int);
3091 extern int noop_fsync(struct file
*, loff_t
, loff_t
, int);
3092 extern int simple_empty(struct dentry
*);
3093 extern int simple_readpage(struct file
*file
, struct page
*page
);
3094 extern int simple_write_begin(struct file
*file
, struct address_space
*mapping
,
3095 loff_t pos
, unsigned len
, unsigned flags
,
3096 struct page
**pagep
, void **fsdata
);
3097 extern int simple_write_end(struct file
*file
, struct address_space
*mapping
,
3098 loff_t pos
, unsigned len
, unsigned copied
,
3099 struct page
*page
, void *fsdata
);
3100 extern int always_delete_dentry(const struct dentry
*);
3101 extern struct inode
*alloc_anon_inode(struct super_block
*);
3102 extern int simple_nosetlease(struct file
*, long, struct file_lock
**, void **);
3103 extern const struct dentry_operations simple_dentry_operations
;
3105 extern struct dentry
*simple_lookup(struct inode
*, struct dentry
*, unsigned int flags
);
3106 extern ssize_t
generic_read_dir(struct file
*, char __user
*, size_t, loff_t
*);
3107 extern const struct file_operations simple_dir_operations
;
3108 extern const struct inode_operations simple_dir_inode_operations
;
3109 extern void make_empty_dir_inode(struct inode
*inode
);
3110 extern bool is_empty_dir_inode(struct inode
*inode
);
3111 struct tree_descr
{ const char *name
; const struct file_operations
*ops
; int mode
; };
3112 struct dentry
*d_alloc_name(struct dentry
*, const char *);
3113 extern int simple_fill_super(struct super_block
*, unsigned long,
3114 const struct tree_descr
*);
3115 extern int simple_pin_fs(struct file_system_type
*, struct vfsmount
**mount
, int *count
);
3116 extern void simple_release_fs(struct vfsmount
**mount
, int *count
);
3118 extern ssize_t
simple_read_from_buffer(void __user
*to
, size_t count
,
3119 loff_t
*ppos
, const void *from
, size_t available
);
3120 extern ssize_t
simple_write_to_buffer(void *to
, size_t available
, loff_t
*ppos
,
3121 const void __user
*from
, size_t count
);
3123 extern int __generic_file_fsync(struct file
*, loff_t
, loff_t
, int);
3124 extern int generic_file_fsync(struct file
*, loff_t
, loff_t
, int);
3126 extern int generic_check_addressable(unsigned, u64
);
3128 #ifdef CONFIG_MIGRATION
3129 extern int buffer_migrate_page(struct address_space
*,
3130 struct page
*, struct page
*,
3133 #define buffer_migrate_page NULL
3136 extern int setattr_prepare(struct dentry
*, struct iattr
*);
3137 extern int inode_newsize_ok(const struct inode
*, loff_t offset
);
3138 extern void setattr_copy(struct inode
*inode
, const struct iattr
*attr
);
3140 extern int file_update_time(struct file
*file
);
3142 static inline bool io_is_direct(struct file
*filp
)
3144 return (filp
->f_flags
& O_DIRECT
) || IS_DAX(filp
->f_mapping
->host
);
3147 static inline bool vma_is_dax(struct vm_area_struct
*vma
)
3149 return vma
->vm_file
&& IS_DAX(vma
->vm_file
->f_mapping
->host
);
3152 static inline int iocb_flags(struct file
*file
)
3155 if (file
->f_flags
& O_APPEND
)
3157 if (io_is_direct(file
))
3159 if ((file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
))
3161 if (file
->f_flags
& __O_SYNC
)
3166 static inline int kiocb_set_rw_flags(struct kiocb
*ki
, rwf_t flags
)
3168 if (unlikely(flags
& ~RWF_SUPPORTED
))
3171 if (flags
& RWF_NOWAIT
) {
3172 if (!(ki
->ki_filp
->f_mode
& FMODE_AIO_NOWAIT
))
3174 ki
->ki_flags
|= IOCB_NOWAIT
;
3176 if (flags
& RWF_HIPRI
)
3177 ki
->ki_flags
|= IOCB_HIPRI
;
3178 if (flags
& RWF_DSYNC
)
3179 ki
->ki_flags
|= IOCB_DSYNC
;
3180 if (flags
& RWF_SYNC
)
3181 ki
->ki_flags
|= (IOCB_DSYNC
| IOCB_SYNC
);
3185 static inline ino_t
parent_ino(struct dentry
*dentry
)
3190 * Don't strictly need d_lock here? If the parent ino could change
3191 * then surely we'd have a deeper race in the caller?
3193 spin_lock(&dentry
->d_lock
);
3194 res
= dentry
->d_parent
->d_inode
->i_ino
;
3195 spin_unlock(&dentry
->d_lock
);
3199 /* Transaction based IO helpers */
3202 * An argresp is stored in an allocated page and holds the
3203 * size of the argument or response, along with its content
3205 struct simple_transaction_argresp
{
3210 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3212 char *simple_transaction_get(struct file
*file
, const char __user
*buf
,
3214 ssize_t
simple_transaction_read(struct file
*file
, char __user
*buf
,
3215 size_t size
, loff_t
*pos
);
3216 int simple_transaction_release(struct inode
*inode
, struct file
*file
);
3218 void simple_transaction_set(struct file
*file
, size_t n
);
3221 * simple attribute files
3223 * These attributes behave similar to those in sysfs:
3225 * Writing to an attribute immediately sets a value, an open file can be
3226 * written to multiple times.
3228 * Reading from an attribute creates a buffer from the value that might get
3229 * read with multiple read calls. When the attribute has been read
3230 * completely, no further read calls are possible until the file is opened
3233 * All attributes contain a text representation of a numeric value
3234 * that are accessed with the get() and set() functions.
3236 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3237 static int __fops ## _open(struct inode *inode, struct file *file) \
3239 __simple_attr_check_format(__fmt, 0ull); \
3240 return simple_attr_open(inode, file, __get, __set, __fmt); \
3242 static const struct file_operations __fops = { \
3243 .owner = THIS_MODULE, \
3244 .open = __fops ## _open, \
3245 .release = simple_attr_release, \
3246 .read = simple_attr_read, \
3247 .write = simple_attr_write, \
3248 .llseek = generic_file_llseek, \
3251 static inline __printf(1, 2)
3252 void __simple_attr_check_format(const char *fmt
, ...)
3254 /* don't do anything, just let the compiler check the arguments; */
3257 int simple_attr_open(struct inode
*inode
, struct file
*file
,
3258 int (*get
)(void *, u64
*), int (*set
)(void *, u64
),
3260 int simple_attr_release(struct inode
*inode
, struct file
*file
);
3261 ssize_t
simple_attr_read(struct file
*file
, char __user
*buf
,
3262 size_t len
, loff_t
*ppos
);
3263 ssize_t
simple_attr_write(struct file
*file
, const char __user
*buf
,
3264 size_t len
, loff_t
*ppos
);
3267 int proc_nr_files(struct ctl_table
*table
, int write
,
3268 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
3269 int proc_nr_dentry(struct ctl_table
*table
, int write
,
3270 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
3271 int proc_nr_inodes(struct ctl_table
*table
, int write
,
3272 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
3273 int __init
get_filesystem_list(char *buf
);
3275 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3276 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3278 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3279 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3280 (flag & __FMODE_NONOTIFY)))
3282 static inline bool is_sxid(umode_t mode
)
3284 return (mode
& S_ISUID
) || ((mode
& S_ISGID
) && (mode
& S_IXGRP
));
3287 static inline int check_sticky(struct inode
*dir
, struct inode
*inode
)
3289 if (!(dir
->i_mode
& S_ISVTX
))
3292 return __check_sticky(dir
, inode
);
3295 static inline void inode_has_no_xattr(struct inode
*inode
)
3297 if (!is_sxid(inode
->i_mode
) && (inode
->i_sb
->s_flags
& MS_NOSEC
))
3298 inode
->i_flags
|= S_NOSEC
;
3301 static inline bool is_root_inode(struct inode
*inode
)
3303 return inode
== inode
->i_sb
->s_root
->d_inode
;
3306 static inline bool dir_emit(struct dir_context
*ctx
,
3307 const char *name
, int namelen
,
3308 u64 ino
, unsigned type
)
3310 return ctx
->actor(ctx
, name
, namelen
, ctx
->pos
, ino
, type
) == 0;
3312 static inline bool dir_emit_dot(struct file
*file
, struct dir_context
*ctx
)
3314 return ctx
->actor(ctx
, ".", 1, ctx
->pos
,
3315 file
->f_path
.dentry
->d_inode
->i_ino
, DT_DIR
) == 0;
3317 static inline bool dir_emit_dotdot(struct file
*file
, struct dir_context
*ctx
)
3319 return ctx
->actor(ctx
, "..", 2, ctx
->pos
,
3320 parent_ino(file
->f_path
.dentry
), DT_DIR
) == 0;
3322 static inline bool dir_emit_dots(struct file
*file
, struct dir_context
*ctx
)
3324 if (ctx
->pos
== 0) {
3325 if (!dir_emit_dot(file
, ctx
))
3329 if (ctx
->pos
== 1) {
3330 if (!dir_emit_dotdot(file
, ctx
))
3336 static inline bool dir_relax(struct inode
*inode
)
3338 inode_unlock(inode
);
3340 return !IS_DEADDIR(inode
);
3343 static inline bool dir_relax_shared(struct inode
*inode
)
3345 inode_unlock_shared(inode
);
3346 inode_lock_shared(inode
);
3347 return !IS_DEADDIR(inode
);
3350 extern bool path_noexec(const struct path
*path
);
3351 extern void inode_nohighmem(struct inode
*inode
);
3353 #endif /* _LINUX_FS_H */