4 #include <linux/linkage.h>
5 #include <linux/wait.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/capability.h>
22 #include <linux/semaphore.h>
23 #include <linux/fiemap.h>
24 #include <linux/rculist_bl.h>
25 #include <linux/atomic.h>
26 #include <linux/shrinker.h>
27 #include <linux/migrate_mode.h>
28 #include <linux/uidgid.h>
29 #include <linux/lockdep.h>
30 #include <linux/percpu-rwsem.h>
31 #include <linux/blk_types.h>
32 #include <linux/workqueue.h>
33 #include <linux/percpu-rwsem.h>
34 #include <linux/delayed_call.h>
36 #include <asm/byteorder.h>
37 #include <uapi/linux/fs.h>
39 struct backing_dev_info;
41 struct export_operations;
46 struct pipe_inode_info;
47 struct poll_table_struct;
49 struct vm_area_struct;
52 struct swap_info_struct;
54 struct workqueue_struct;
57 struct fscrypt_operations;
59 extern void __init inode_init(void);
60 extern void __init inode_init_early(void);
61 extern void __init files_init(void);
62 extern void __init files_maxfiles_init(void);
64 extern struct files_stat_struct files_stat;
65 extern unsigned long get_max_files(void);
66 extern int sysctl_nr_open;
67 extern struct inodes_stat_t inodes_stat;
68 extern int leases_enable, lease_break_time;
69 extern int sysctl_protected_symlinks;
70 extern int sysctl_protected_hardlinks;
73 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
74 struct buffer_head *bh_result, int create);
75 typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
76 ssize_t bytes, void *private);
78 #define MAY_EXEC 0x00000001
79 #define MAY_WRITE 0x00000002
80 #define MAY_READ 0x00000004
81 #define MAY_APPEND 0x00000008
82 #define MAY_ACCESS 0x00000010
83 #define MAY_OPEN 0x00000020
84 #define MAY_CHDIR 0x00000040
85 /* called from RCU mode, don't block */
86 #define MAY_NOT_BLOCK 0x00000080
89 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
90 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
93 /* file is open for reading */
94 #define FMODE_READ ((__force fmode_t)0x1)
95 /* file is open for writing */
96 #define FMODE_WRITE ((__force fmode_t)0x2)
97 /* file is seekable */
98 #define FMODE_LSEEK ((__force fmode_t)0x4)
99 /* file can be accessed using pread */
100 #define FMODE_PREAD ((__force fmode_t)0x8)
101 /* file can be accessed using pwrite */
102 #define FMODE_PWRITE ((__force fmode_t)0x10)
103 /* File is opened for execution with sys_execve / sys_uselib */
104 #define FMODE_EXEC ((__force fmode_t)0x20)
105 /* File is opened with O_NDELAY (only set for block devices) */
106 #define FMODE_NDELAY ((__force fmode_t)0x40)
107 /* File is opened with O_EXCL (only set for block devices) */
108 #define FMODE_EXCL ((__force fmode_t)0x80)
109 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
110 (specialy hack for floppy.c) */
111 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
112 /* 32bit hashes as llseek() offset (for directories) */
113 #define FMODE_32BITHASH ((__force fmode_t)0x200)
114 /* 64bit hashes as llseek() offset (for directories) */
115 #define FMODE_64BITHASH ((__force fmode_t)0x400)
118 * Don't update ctime and mtime.
120 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
121 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
123 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
125 /* Expect random access pattern */
126 #define FMODE_RANDOM ((__force fmode_t)0x1000)
128 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
129 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
131 /* File is opened with O_PATH; almost nothing can be done with it */
132 #define FMODE_PATH ((__force fmode_t)0x4000)
134 /* File needs atomic accesses to f_pos */
135 #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
136 /* Write access to underlying fs */
137 #define FMODE_WRITER ((__force fmode_t)0x10000)
138 /* Has read method(s) */
139 #define FMODE_CAN_READ ((__force fmode_t)0x20000)
140 /* Has write method(s) */
141 #define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
143 /* File was opened by fanotify and shouldn't generate fanotify events */
144 #define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
147 * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
148 * that indicates that they should check the contents of the iovec are
149 * valid, but not check the memory that the iovec elements
152 #define CHECK_IOVEC_ONLY -1
155 * The below are the various read and write types that we support. Some of
156 * them include behavioral modifiers that send information down to the
157 * block layer and IO scheduler. Terminology:
159 * The block layer uses device plugging to defer IO a little bit, in
160 * the hope that we will see more IO very shortly. This increases
161 * coalescing of adjacent IO and thus reduces the number of IOs we
162 * have to send to the device. It also allows for better queuing,
163 * if the IO isn't mergeable. If the caller is going to be waiting
164 * for the IO, then he must ensure that the device is unplugged so
165 * that the IO is dispatched to the driver.
167 * All IO is handled async in Linux. This is fine for background
168 * writes, but for reads or writes that someone waits for completion
169 * on, we want to notify the block layer and IO scheduler so that they
170 * know about it. That allows them to make better scheduling
171 * decisions. So when the below references 'sync' and 'async', it
172 * is referencing this priority hint.
174 * With that in mind, the available types are:
176 * READ A normal read operation. Device will be plugged.
177 * READ_SYNC A synchronous read. Device is not plugged, caller can
178 * immediately wait on this read without caring about
180 * READA Used for read-ahead operations. Lower priority, and the
181 * block layer could (in theory) choose to ignore this
182 * request if it runs into resource problems.
183 * WRITE A normal async write. Device will be plugged.
184 * WRITE_SYNC Synchronous write. Identical to WRITE, but passes down
185 * the hint that someone will be waiting on this IO
186 * shortly. The write equivalent of READ_SYNC.
187 * WRITE_ODIRECT Special case write for O_DIRECT only.
188 * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush.
189 * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on
190 * non-volatile media on completion.
191 * WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded
192 * by a cache flush and data is guaranteed to be on
193 * non-volatile media on completion.
196 #define RW_MASK REQ_WRITE
197 #define RWA_MASK REQ_RAHEAD
200 #define WRITE RW_MASK
201 #define READA RWA_MASK
203 #define READ_SYNC (READ | REQ_SYNC)
204 #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE)
205 #define WRITE_ODIRECT (WRITE | REQ_SYNC)
206 #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH)
207 #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
208 #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
211 * Attribute flags. These should be or-ed together to figure out what
214 #define ATTR_MODE (1 << 0)
215 #define ATTR_UID (1 << 1)
216 #define ATTR_GID (1 << 2)
217 #define ATTR_SIZE (1 << 3)
218 #define ATTR_ATIME (1 << 4)
219 #define ATTR_MTIME (1 << 5)
220 #define ATTR_CTIME (1 << 6)
221 #define ATTR_ATIME_SET (1 << 7)
222 #define ATTR_MTIME_SET (1 << 8)
223 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
224 #define ATTR_ATTR_FLAG (1 << 10)
225 #define ATTR_KILL_SUID (1 << 11)
226 #define ATTR_KILL_SGID (1 << 12)
227 #define ATTR_FILE (1 << 13)
228 #define ATTR_KILL_PRIV (1 << 14)
229 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
230 #define ATTR_TIMES_SET (1 << 16)
233 * Whiteout is represented by a char device. The following constants define the
234 * mode and device number to use.
236 #define WHITEOUT_MODE 0
237 #define WHITEOUT_DEV 0
240 * This is the Inode Attributes structure, used for notify_change(). It
241 * uses the above definitions as flags, to know which values have changed.
242 * Also, in this manner, a Filesystem can look at only the values it cares
243 * about. Basically, these are the attributes that the VFS layer can
244 * request to change from the FS layer.
246 * Derek Atkins <warlord@MIT.EDU> 94-10-20
249 unsigned int ia_valid;
254 struct timespec ia_atime;
255 struct timespec ia_mtime;
256 struct timespec ia_ctime;
259 * Not an attribute, but an auxiliary info for filesystems wanting to
260 * implement an ftruncate() like method. NOTE: filesystem should
261 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
263 struct file *ia_file;
267 * Includes for diskquotas.
269 #include <linux/quota.h>
272 * Maximum number of layers of fs stack. Needs to be limited to
273 * prevent kernel stack overflow
275 #define FILESYSTEM_MAX_STACK_DEPTH 2
278 * enum positive_aop_returns - aop return codes with specific semantics
280 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
281 * completed, that the page is still locked, and
282 * should be considered active. The VM uses this hint
283 * to return the page to the active list -- it won't
284 * be a candidate for writeback again in the near
285 * future. Other callers must be careful to unlock
286 * the page if they get this return. Returned by
289 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
290 * unlocked it and the page might have been truncated.
291 * The caller should back up to acquiring a new page and
292 * trying again. The aop will be taking reasonable
293 * precautions not to livelock. If the caller held a page
294 * reference, it should drop it before retrying. Returned
297 * address_space_operation functions return these large constants to indicate
298 * special semantics to the caller. These are much larger than the bytes in a
299 * page to allow for functions that return the number of bytes operated on in a
303 enum positive_aop_returns {
304 AOP_WRITEPAGE_ACTIVATE = 0x80000,
305 AOP_TRUNCATED_PAGE = 0x80001,
308 #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
309 #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
310 #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct
311 * helper code (eg buffer layer)
312 * to clear GFP_FS from alloc */
315 * oh the beauties of C type declarations.
318 struct address_space;
319 struct writeback_control;
321 #define IOCB_EVENTFD (1 << 0)
322 #define IOCB_APPEND (1 << 1)
323 #define IOCB_DIRECT (1 << 2)
324 #define IOCB_HIPRI (1 << 3)
325 #define IOCB_DSYNC (1 << 4)
326 #define IOCB_SYNC (1 << 5)
329 struct file *ki_filp;
331 void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
336 static inline bool is_sync_kiocb(struct kiocb *kiocb)
338 return kiocb->ki_complete == NULL;
341 static inline int iocb_flags(struct file *file);
343 static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
345 *kiocb = (struct kiocb) {
347 .ki_flags = iocb_flags(filp),
352 * "descriptor" for what we're up to with a read.
353 * This allows us to use the same read code yet
354 * have multiple different users of the data that
355 * we read from a file.
357 * The simplest case just copies the data to user
370 typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
371 unsigned long, unsigned long);
373 struct address_space_operations {
374 int (*writepage)(struct page *page, struct writeback_control *wbc);
375 int (*readpage)(struct file *, struct page *);
377 /* Write back some dirty pages from this mapping. */
378 int (*writepages)(struct address_space *, struct writeback_control *);
380 /* Set a page dirty. Return true if this dirtied it */
381 int (*set_page_dirty)(struct page *page);
383 int (*readpages)(struct file *filp, struct address_space *mapping,
384 struct list_head *pages, unsigned nr_pages);
386 int (*write_begin)(struct file *, struct address_space *mapping,
387 loff_t pos, unsigned len, unsigned flags,
388 struct page **pagep, void **fsdata);
389 int (*write_end)(struct file *, struct address_space *mapping,
390 loff_t pos, unsigned len, unsigned copied,
391 struct page *page, void *fsdata);
393 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
394 sector_t (*bmap)(struct address_space *, sector_t);
395 void (*invalidatepage) (struct page *, unsigned int, unsigned int);
396 int (*releasepage) (struct page *, gfp_t);
397 void (*freepage)(struct page *);
398 ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
400 * migrate the contents of a page to the specified target. If
401 * migrate_mode is MIGRATE_ASYNC, it must not block.
403 int (*migratepage) (struct address_space *,
404 struct page *, struct page *, enum migrate_mode);
405 int (*launder_page) (struct page *);
406 int (*is_partially_uptodate) (struct page *, unsigned long,
408 void (*is_dirty_writeback) (struct page *, bool *, bool *);
409 int (*error_remove_page)(struct address_space *, struct page *);
411 /* swapfile support */
412 int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
414 void (*swap_deactivate)(struct file *file);
417 extern const struct address_space_operations empty_aops;
420 * pagecache_write_begin/pagecache_write_end must be used by general code
421 * to write into the pagecache.
423 int pagecache_write_begin(struct file *, struct address_space *mapping,
424 loff_t pos, unsigned len, unsigned flags,
425 struct page **pagep, void **fsdata);
427 int pagecache_write_end(struct file *, struct address_space *mapping,
428 loff_t pos, unsigned len, unsigned copied,
429 struct page *page, void *fsdata);
431 struct address_space {
432 struct inode *host; /* owner: inode, block_device */
433 struct radix_tree_root page_tree; /* radix tree of all pages */
434 spinlock_t tree_lock; /* and lock protecting it */
435 atomic_t i_mmap_writable;/* count VM_SHARED mappings */
436 struct rb_root i_mmap; /* tree of private and shared mappings */
437 struct rw_semaphore i_mmap_rwsem; /* protect tree, count, list */
438 /* Protected by tree_lock together with the radix tree */
439 unsigned long nrpages; /* number of total pages */
440 /* number of shadow or DAX exceptional entries */
441 unsigned long nrexceptional;
442 pgoff_t writeback_index;/* writeback starts here */
443 const struct address_space_operations *a_ops; /* methods */
444 unsigned long flags; /* error bits/gfp mask */
445 spinlock_t private_lock; /* for use by the address_space */
446 struct list_head private_list; /* ditto */
447 void *private_data; /* ditto */
448 } __attribute__((aligned(sizeof(long))));
450 * On most architectures that alignment is already the case; but
451 * must be enforced here for CRIS, to let the least significant bit
452 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
454 struct request_queue;
456 struct block_device {
457 dev_t bd_dev; /* not a kdev_t - it's a search key */
459 struct inode * bd_inode; /* will die */
460 struct super_block * bd_super;
461 struct mutex bd_mutex; /* open/close mutex */
462 struct list_head bd_inodes;
466 bool bd_write_holder;
468 struct list_head bd_holder_disks;
470 struct block_device * bd_contains;
471 unsigned bd_block_size;
472 struct hd_struct * bd_part;
473 /* number of times partitions within this device have been opened. */
474 unsigned bd_part_count;
476 struct gendisk * bd_disk;
477 struct request_queue * bd_queue;
478 struct list_head bd_list;
480 * Private data. You must have bd_claim'ed the block_device
481 * to use this. NOTE: bd_claim allows an owner to claim
482 * the same device multiple times, the owner must take special
483 * care to not mess up bd_private for that case.
485 unsigned long bd_private;
487 /* The counter of freeze processes */
488 int bd_fsfreeze_count;
489 /* Mutex for freeze */
490 struct mutex bd_fsfreeze_mutex;
494 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
497 #define PAGECACHE_TAG_DIRTY 0
498 #define PAGECACHE_TAG_WRITEBACK 1
499 #define PAGECACHE_TAG_TOWRITE 2
501 int mapping_tagged(struct address_space *mapping, int tag);
503 static inline void i_mmap_lock_write(struct address_space *mapping)
505 down_write(&mapping->i_mmap_rwsem);
508 static inline void i_mmap_unlock_write(struct address_space *mapping)
510 up_write(&mapping->i_mmap_rwsem);
513 static inline void i_mmap_lock_read(struct address_space *mapping)
515 down_read(&mapping->i_mmap_rwsem);
518 static inline void i_mmap_unlock_read(struct address_space *mapping)
520 up_read(&mapping->i_mmap_rwsem);
524 * Might pages of this file be mapped into userspace?
526 static inline int mapping_mapped(struct address_space *mapping)
528 return !RB_EMPTY_ROOT(&mapping->i_mmap);
532 * Might pages of this file have been modified in userspace?
533 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
534 * marks vma as VM_SHARED if it is shared, and the file was opened for
535 * writing i.e. vma may be mprotected writable even if now readonly.
537 * If i_mmap_writable is negative, no new writable mappings are allowed. You
538 * can only deny writable mappings, if none exists right now.
540 static inline int mapping_writably_mapped(struct address_space *mapping)
542 return atomic_read(&mapping->i_mmap_writable) > 0;
545 static inline int mapping_map_writable(struct address_space *mapping)
547 return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
551 static inline void mapping_unmap_writable(struct address_space *mapping)
553 atomic_dec(&mapping->i_mmap_writable);
556 static inline int mapping_deny_writable(struct address_space *mapping)
558 return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
562 static inline void mapping_allow_writable(struct address_space *mapping)
564 atomic_inc(&mapping->i_mmap_writable);
568 * Use sequence counter to get consistent i_size on 32-bit processors.
570 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
571 #include <linux/seqlock.h>
572 #define __NEED_I_SIZE_ORDERED
573 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
575 #define i_size_ordered_init(inode) do { } while (0)
579 #define ACL_NOT_CACHED ((void *)(-1))
581 static inline struct posix_acl *
582 uncached_acl_sentinel(struct task_struct *task)
584 return (void *)task + 1;
588 is_uncached_acl(struct posix_acl *acl)
590 return (long)acl & 1;
593 #define IOP_FASTPERM 0x0001
594 #define IOP_LOOKUP 0x0002
595 #define IOP_NOFOLLOW 0x0004
598 * Keep mostly read-only and often accessed (especially for
599 * the RCU path lookup and 'stat' data) fields at the beginning
600 * of the 'struct inode'
604 unsigned short i_opflags;
607 unsigned int i_flags;
609 #ifdef CONFIG_FS_POSIX_ACL
610 struct posix_acl *i_acl;
611 struct posix_acl *i_default_acl;
614 const struct inode_operations *i_op;
615 struct super_block *i_sb;
616 struct address_space *i_mapping;
618 #ifdef CONFIG_SECURITY
622 /* Stat data, not accessed from path walking */
625 * Filesystems may only read i_nlink directly. They shall use the
626 * following functions for modification:
628 * (set|clear|inc|drop)_nlink
629 * inode_(inc|dec)_link_count
632 const unsigned int i_nlink;
633 unsigned int __i_nlink;
637 struct timespec i_atime;
638 struct timespec i_mtime;
639 struct timespec i_ctime;
640 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
641 unsigned short i_bytes;
642 unsigned int i_blkbits;
645 #ifdef __NEED_I_SIZE_ORDERED
646 seqcount_t i_size_seqcount;
650 unsigned long i_state;
651 struct rw_semaphore i_rwsem;
653 unsigned long dirtied_when; /* jiffies of first dirtying */
654 unsigned long dirtied_time_when;
656 struct hlist_node i_hash;
657 struct list_head i_io_list; /* backing dev IO list */
658 #ifdef CONFIG_CGROUP_WRITEBACK
659 struct bdi_writeback *i_wb; /* the associated cgroup wb */
661 /* foreign inode detection, see wbc_detach_inode() */
663 u16 i_wb_frn_avg_time;
664 u16 i_wb_frn_history;
666 struct list_head i_lru; /* inode LRU list */
667 struct list_head i_sb_list;
669 struct hlist_head i_dentry;
670 struct rcu_head i_rcu;
674 atomic_t i_dio_count;
675 atomic_t i_writecount;
677 atomic_t i_readcount; /* struct files open RO */
679 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
680 struct file_lock_context *i_flctx;
681 struct address_space i_data;
682 struct list_head i_devices;
684 struct pipe_inode_info *i_pipe;
685 struct block_device *i_bdev;
693 #ifdef CONFIG_FSNOTIFY
694 __u32 i_fsnotify_mask; /* all events this inode cares about */
695 struct hlist_head i_fsnotify_marks;
698 #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
699 struct fscrypt_info *i_crypt_info;
702 void *i_private; /* fs or device private pointer */
705 static inline int inode_unhashed(struct inode *inode)
707 return hlist_unhashed(&inode->i_hash);
711 * inode->i_mutex nesting subclasses for the lock validator:
713 * 0: the object of the current VFS operation
717 * 4: second non-directory
718 * 5: second parent (when locking independent directories in rename)
720 * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
721 * non-directories at once.
723 * The locking order between these classes is
724 * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
726 enum inode_i_mutex_lock_class
736 static inline void inode_lock(struct inode *inode)
738 down_write(&inode->i_rwsem);
741 static inline void inode_unlock(struct inode *inode)
743 up_write(&inode->i_rwsem);
746 static inline void inode_lock_shared(struct inode *inode)
748 down_read(&inode->i_rwsem);
751 static inline void inode_unlock_shared(struct inode *inode)
753 up_read(&inode->i_rwsem);
756 static inline int inode_trylock(struct inode *inode)
758 return down_write_trylock(&inode->i_rwsem);
761 static inline int inode_trylock_shared(struct inode *inode)
763 return down_read_trylock(&inode->i_rwsem);
766 static inline int inode_is_locked(struct inode *inode)
768 return rwsem_is_locked(&inode->i_rwsem);
771 static inline void inode_lock_nested(struct inode *inode, unsigned subclass)
773 down_write_nested(&inode->i_rwsem, subclass);
776 void lock_two_nondirectories(struct inode *, struct inode*);
777 void unlock_two_nondirectories(struct inode *, struct inode*);
780 * NOTE: in a 32bit arch with a preemptable kernel and
781 * an UP compile the i_size_read/write must be atomic
782 * with respect to the local cpu (unlike with preempt disabled),
783 * but they don't need to be atomic with respect to other cpus like in
784 * true SMP (so they need either to either locally disable irq around
785 * the read or for example on x86 they can be still implemented as a
786 * cmpxchg8b without the need of the lock prefix). For SMP compiles
787 * and 64bit archs it makes no difference if preempt is enabled or not.
789 static inline loff_t i_size_read(const struct inode *inode)
791 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
796 seq = read_seqcount_begin(&inode->i_size_seqcount);
797 i_size = inode->i_size;
798 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
800 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
804 i_size = inode->i_size;
808 return inode->i_size;
813 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
814 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
815 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
817 static inline void i_size_write(struct inode *inode, loff_t i_size)
819 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
821 write_seqcount_begin(&inode->i_size_seqcount);
822 inode->i_size = i_size;
823 write_seqcount_end(&inode->i_size_seqcount);
825 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
827 inode->i_size = i_size;
830 inode->i_size = i_size;
834 /* Helper functions so that in most cases filesystems will
835 * not need to deal directly with kuid_t and kgid_t and can
836 * instead deal with the raw numeric values that are stored
839 static inline uid_t i_uid_read(const struct inode *inode)
841 return from_kuid(&init_user_ns, inode->i_uid);
844 static inline gid_t i_gid_read(const struct inode *inode)
846 return from_kgid(&init_user_ns, inode->i_gid);
849 static inline void i_uid_write(struct inode *inode, uid_t uid)
851 inode->i_uid = make_kuid(&init_user_ns, uid);
854 static inline void i_gid_write(struct inode *inode, gid_t gid)
856 inode->i_gid = make_kgid(&init_user_ns, gid);
859 static inline unsigned iminor(const struct inode *inode)
861 return MINOR(inode->i_rdev);
864 static inline unsigned imajor(const struct inode *inode)
866 return MAJOR(inode->i_rdev);
869 extern struct block_device *I_BDEV(struct inode *inode);
872 rwlock_t lock; /* protects pid, uid, euid fields */
873 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
874 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
875 kuid_t uid, euid; /* uid/euid of process setting the owner */
876 int signum; /* posix.1b rt signal to be delivered on IO */
880 * Track a single file's readahead state
882 struct file_ra_state {
883 pgoff_t start; /* where readahead started */
884 unsigned int size; /* # of readahead pages */
885 unsigned int async_size; /* do asynchronous readahead when
886 there are only # of pages ahead */
888 unsigned int ra_pages; /* Maximum readahead window */
889 unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
890 loff_t prev_pos; /* Cache last read() position */
894 * Check if @index falls in the readahead windows.
896 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
898 return (index >= ra->start &&
899 index < ra->start + ra->size);
904 struct llist_node fu_llist;
905 struct rcu_head fu_rcuhead;
908 struct inode *f_inode; /* cached value */
909 const struct file_operations *f_op;
912 * Protects f_ep_links, f_flags.
913 * Must not be taken from IRQ context.
916 atomic_long_t f_count;
917 unsigned int f_flags;
919 struct mutex f_pos_lock;
921 struct fown_struct f_owner;
922 const struct cred *f_cred;
923 struct file_ra_state f_ra;
926 #ifdef CONFIG_SECURITY
929 /* needed for tty driver, and maybe others */
933 /* Used by fs/eventpoll.c to link all the hooks to this file */
934 struct list_head f_ep_links;
935 struct list_head f_tfile_llink;
936 #endif /* #ifdef CONFIG_EPOLL */
937 struct address_space *f_mapping;
938 } __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
943 /* file identifier */
944 unsigned char f_handle[0];
947 static inline struct file *get_file(struct file *f)
949 atomic_long_inc(&f->f_count);
952 #define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
953 #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
954 #define file_count(x) atomic_long_read(&(x)->f_count)
956 #define MAX_NON_LFS ((1UL<<31) - 1)
958 /* Page cache limit. The filesystems should put that into their s_maxbytes
959 limits, otherwise bad things can happen in VM. */
960 #if BITS_PER_LONG==32
961 #define MAX_LFS_FILESIZE (((loff_t)PAGE_SIZE << (BITS_PER_LONG-1))-1)
962 #elif BITS_PER_LONG==64
963 #define MAX_LFS_FILESIZE ((loff_t)0x7fffffffffffffffLL)
968 #define FL_DELEG 4 /* NFSv4 delegation */
969 #define FL_ACCESS 8 /* not trying to lock, just looking */
970 #define FL_EXISTS 16 /* when unlocking, test for existence */
971 #define FL_LEASE 32 /* lease held on this file */
972 #define FL_CLOSE 64 /* unlock on close */
973 #define FL_SLEEP 128 /* A blocking lock */
974 #define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
975 #define FL_UNLOCK_PENDING 512 /* Lease is being broken */
976 #define FL_OFDLCK 1024 /* lock is "owned" by struct file */
977 #define FL_LAYOUT 2048 /* outstanding pNFS layout */
980 * Special return value from posix_lock_file() and vfs_lock_file() for
981 * asynchronous locking.
983 #define FILE_LOCK_DEFERRED 1
985 /* legacy typedef, should eventually be removed */
986 typedef void *fl_owner_t;
990 struct file_lock_operations {
991 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
992 void (*fl_release_private)(struct file_lock *);
995 struct lock_manager_operations {
996 int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
997 unsigned long (*lm_owner_key)(struct file_lock *);
998 fl_owner_t (*lm_get_owner)(fl_owner_t);
999 void (*lm_put_owner)(fl_owner_t);
1000 void (*lm_notify)(struct file_lock *); /* unblock callback */
1001 int (*lm_grant)(struct file_lock *, int);
1002 bool (*lm_break)(struct file_lock *);
1003 int (*lm_change)(struct file_lock *, int, struct list_head *);
1004 void (*lm_setup)(struct file_lock *, void **);
1007 struct lock_manager {
1008 struct list_head list;
1010 * NFSv4 and up also want opens blocked during the grace period;
1017 void locks_start_grace(struct net *, struct lock_manager *);
1018 void locks_end_grace(struct lock_manager *);
1019 int locks_in_grace(struct net *);
1020 int opens_in_grace(struct net *);
1022 /* that will die - we need it for nfs_lock_info */
1023 #include <linux/nfs_fs_i.h>
1026 * struct file_lock represents a generic "file lock". It's used to represent
1027 * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
1028 * note that the same struct is used to represent both a request for a lock and
1029 * the lock itself, but the same object is never used for both.
1031 * FIXME: should we create a separate "struct lock_request" to help distinguish
1034 * The varous i_flctx lists are ordered by:
1037 * 2) lock range start
1040 * Obviously, the last two criteria only matter for POSIX locks.
1043 struct file_lock *fl_next; /* singly linked list for this inode */
1044 struct list_head fl_list; /* link into file_lock_context */
1045 struct hlist_node fl_link; /* node in global lists */
1046 struct list_head fl_block; /* circular list of blocked processes */
1047 fl_owner_t fl_owner;
1048 unsigned int fl_flags;
1049 unsigned char fl_type;
1050 unsigned int fl_pid;
1051 int fl_link_cpu; /* what cpu's list is this on? */
1052 struct pid *fl_nspid;
1053 wait_queue_head_t fl_wait;
1054 struct file *fl_file;
1058 struct fasync_struct * fl_fasync; /* for lease break notifications */
1059 /* for lease breaks: */
1060 unsigned long fl_break_time;
1061 unsigned long fl_downgrade_time;
1063 const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
1064 const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
1066 struct nfs_lock_info nfs_fl;
1067 struct nfs4_lock_info nfs4_fl;
1069 struct list_head link; /* link in AFS vnode's pending_locks list */
1070 int state; /* state of grant or error if -ve */
1075 struct file_lock_context {
1076 spinlock_t flc_lock;
1077 struct list_head flc_flock;
1078 struct list_head flc_posix;
1079 struct list_head flc_lease;
1082 /* The following constant reflects the upper bound of the file/locking space */
1084 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
1085 #define OFFSET_MAX INT_LIMIT(loff_t)
1086 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
1089 #include <linux/fcntl.h>
1091 extern void send_sigio(struct fown_struct *fown, int fd, int band);
1093 #ifdef CONFIG_FILE_LOCKING
1094 extern int fcntl_getlk(struct file *, unsigned int, struct flock __user *);
1095 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
1096 struct flock __user *);
1098 #if BITS_PER_LONG == 32
1099 extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 __user *);
1100 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
1101 struct flock64 __user *);
1104 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
1105 extern int fcntl_getlease(struct file *filp);
1108 void locks_free_lock_context(struct inode *inode);
1109 void locks_free_lock(struct file_lock *fl);
1110 extern void locks_init_lock(struct file_lock *);
1111 extern struct file_lock * locks_alloc_lock(void);
1112 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1113 extern void locks_copy_conflock(struct file_lock *, struct file_lock *);
1114 extern void locks_remove_posix(struct file *, fl_owner_t);
1115 extern void locks_remove_file(struct file *);
1116 extern void locks_release_private(struct file_lock *);
1117 extern void posix_test_lock(struct file *, struct file_lock *);
1118 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
1119 extern int posix_unblock_lock(struct file_lock *);
1120 extern int vfs_test_lock(struct file *, struct file_lock *);
1121 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
1122 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
1123 extern int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl);
1124 extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
1125 extern void lease_get_mtime(struct inode *, struct timespec *time);
1126 extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
1127 extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
1128 extern int lease_modify(struct file_lock *, int, struct list_head *);
1129 struct files_struct;
1130 extern void show_fd_locks(struct seq_file *f,
1131 struct file *filp, struct files_struct *files);
1132 #else /* !CONFIG_FILE_LOCKING */
1133 static inline int fcntl_getlk(struct file *file, unsigned int cmd,
1134 struct flock __user *user)
1139 static inline int fcntl_setlk(unsigned int fd, struct file *file,
1140 unsigned int cmd, struct flock __user *user)
1145 #if BITS_PER_LONG == 32
1146 static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
1147 struct flock64 __user *user)
1152 static inline int fcntl_setlk64(unsigned int fd, struct file *file,
1153 unsigned int cmd, struct flock64 __user *user)
1158 static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
1163 static inline int fcntl_getlease(struct file *filp)
1169 locks_free_lock_context(struct inode *inode)
1173 static inline void locks_init_lock(struct file_lock *fl)
1178 static inline void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
1183 static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1188 static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
1193 static inline void locks_remove_file(struct file *filp)
1198 static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
1203 static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
1204 struct file_lock *conflock)
1209 static inline int posix_unblock_lock(struct file_lock *waiter)
1214 static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
1219 static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
1220 struct file_lock *fl, struct file_lock *conf)
1225 static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
1230 static inline int locks_lock_inode_wait(struct inode *inode, struct file_lock *fl)
1235 static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
1240 static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
1245 static inline int generic_setlease(struct file *filp, long arg,
1246 struct file_lock **flp, void **priv)
1251 static inline int vfs_setlease(struct file *filp, long arg,
1252 struct file_lock **lease, void **priv)
1257 static inline int lease_modify(struct file_lock *fl, int arg,
1258 struct list_head *dispose)
1263 struct files_struct;
1264 static inline void show_fd_locks(struct seq_file *f,
1265 struct file *filp, struct files_struct *files) {}
1266 #endif /* !CONFIG_FILE_LOCKING */
1268 static inline struct inode *file_inode(const struct file *f)
1273 static inline struct dentry *file_dentry(const struct file *file)
1275 return d_real(file->f_path.dentry, file_inode(file), 0);
1278 static inline int locks_lock_file_wait(struct file *filp, struct file_lock *fl)
1280 return locks_lock_inode_wait(file_inode(filp), fl);
1283 struct fasync_struct {
1287 struct fasync_struct *fa_next; /* singly linked list */
1288 struct file *fa_file;
1289 struct rcu_head fa_rcu;
1292 #define FASYNC_MAGIC 0x4601
1294 /* SMP safe fasync helpers: */
1295 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1296 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1297 extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1298 extern struct fasync_struct *fasync_alloc(void);
1299 extern void fasync_free(struct fasync_struct *);
1301 /* can be called from interrupts */
1302 extern void kill_fasync(struct fasync_struct **, int, int);
1304 extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1305 extern void f_setown(struct file *filp, unsigned long arg, int force);
1306 extern void f_delown(struct file *filp);
1307 extern pid_t f_getown(struct file *filp);
1308 extern int send_sigurg(struct fown_struct *fown);
1316 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1317 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1318 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1319 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1320 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1323 #define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
1324 #define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
1326 /* Possible states of 'frozen' field */
1328 SB_UNFROZEN = 0, /* FS is unfrozen */
1329 SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1330 SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1331 SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1332 * internal threads if needed) */
1333 SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1336 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1339 int frozen; /* Is sb frozen? */
1340 wait_queue_head_t wait_unfrozen; /* for get_super_thawed() */
1341 struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
1344 struct super_block {
1345 struct list_head s_list; /* Keep this first */
1346 dev_t s_dev; /* search index; _not_ kdev_t */
1347 unsigned char s_blocksize_bits;
1348 unsigned long s_blocksize;
1349 loff_t s_maxbytes; /* Max file size */
1350 struct file_system_type *s_type;
1351 const struct super_operations *s_op;
1352 const struct dquot_operations *dq_op;
1353 const struct quotactl_ops *s_qcop;
1354 const struct export_operations *s_export_op;
1355 unsigned long s_flags;
1356 unsigned long s_iflags; /* internal SB_I_* flags */
1357 unsigned long s_magic;
1358 struct dentry *s_root;
1359 struct rw_semaphore s_umount;
1362 #ifdef CONFIG_SECURITY
1365 const struct xattr_handler **s_xattr;
1367 const struct fscrypt_operations *s_cop;
1369 struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
1370 struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1371 struct block_device *s_bdev;
1372 struct backing_dev_info *s_bdi;
1373 struct mtd_info *s_mtd;
1374 struct hlist_node s_instances;
1375 unsigned int s_quota_types; /* Bitmask of supported quota types */
1376 struct quota_info s_dquot; /* Diskquota specific options */
1378 struct sb_writers s_writers;
1380 char s_id[32]; /* Informational name */
1381 u8 s_uuid[16]; /* UUID */
1383 void *s_fs_info; /* Filesystem private info */
1384 unsigned int s_max_links;
1387 /* Granularity of c/m/atime in ns.
1388 Cannot be worse than a second */
1392 * The next field is for VFS *only*. No filesystems have any business
1393 * even looking at it. You had been warned.
1395 struct mutex s_vfs_rename_mutex; /* Kludge */
1398 * Filesystem subtype. If non-empty the filesystem type field
1399 * in /proc/mounts will be "type.subtype"
1404 * Saved mount options for lazy filesystems using
1405 * generic_show_options()
1407 char __rcu *s_options;
1408 const struct dentry_operations *s_d_op; /* default d_op for dentries */
1411 * Saved pool identifier for cleancache (-1 means none)
1413 int cleancache_poolid;
1415 struct shrinker s_shrink; /* per-sb shrinker handle */
1417 /* Number of inodes with nlink == 0 but still referenced */
1418 atomic_long_t s_remove_count;
1420 /* Being remounted read-only */
1421 int s_readonly_remount;
1423 /* AIO completions deferred from interrupt context */
1424 struct workqueue_struct *s_dio_done_wq;
1425 struct hlist_head s_pins;
1428 * Keep the lru lists last in the structure so they always sit on their
1429 * own individual cachelines.
1431 struct list_lru s_dentry_lru ____cacheline_aligned_in_smp;
1432 struct list_lru s_inode_lru ____cacheline_aligned_in_smp;
1433 struct rcu_head rcu;
1434 struct work_struct destroy_work;
1436 struct mutex s_sync_lock; /* sync serialisation lock */
1439 * Indicates how deep in a filesystem stack this SB is
1443 /* s_inode_list_lock protects s_inodes */
1444 spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
1445 struct list_head s_inodes; /* all inodes */
1448 extern struct timespec current_fs_time(struct super_block *sb);
1451 * Snapshotting support.
1454 void __sb_end_write(struct super_block *sb, int level);
1455 int __sb_start_write(struct super_block *sb, int level, bool wait);
1457 #define __sb_writers_acquired(sb, lev) \
1458 percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1459 #define __sb_writers_release(sb, lev) \
1460 percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
1463 * sb_end_write - drop write access to a superblock
1464 * @sb: the super we wrote to
1466 * Decrement number of writers to the filesystem. Wake up possible waiters
1467 * wanting to freeze the filesystem.
1469 static inline void sb_end_write(struct super_block *sb)
1471 __sb_end_write(sb, SB_FREEZE_WRITE);
1475 * sb_end_pagefault - drop write access to a superblock from a page fault
1476 * @sb: the super we wrote to
1478 * Decrement number of processes handling write page fault to the filesystem.
1479 * Wake up possible waiters wanting to freeze the filesystem.
1481 static inline void sb_end_pagefault(struct super_block *sb)
1483 __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1487 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1488 * @sb: the super we wrote to
1490 * Decrement fs-internal number of writers to the filesystem. Wake up possible
1491 * waiters wanting to freeze the filesystem.
1493 static inline void sb_end_intwrite(struct super_block *sb)
1495 __sb_end_write(sb, SB_FREEZE_FS);
1499 * sb_start_write - get write access to a superblock
1500 * @sb: the super we write to
1502 * When a process wants to write data or metadata to a file system (i.e. dirty
1503 * a page or an inode), it should embed the operation in a sb_start_write() -
1504 * sb_end_write() pair to get exclusion against file system freezing. This
1505 * function increments number of writers preventing freezing. If the file
1506 * system is already frozen, the function waits until the file system is
1509 * Since freeze protection behaves as a lock, users have to preserve
1510 * ordering of freeze protection and other filesystem locks. Generally,
1511 * freeze protection should be the outermost lock. In particular, we have:
1514 * -> i_mutex (write path, truncate, directory ops, ...)
1515 * -> s_umount (freeze_super, thaw_super)
1517 static inline void sb_start_write(struct super_block *sb)
1519 __sb_start_write(sb, SB_FREEZE_WRITE, true);
1522 static inline int sb_start_write_trylock(struct super_block *sb)
1524 return __sb_start_write(sb, SB_FREEZE_WRITE, false);
1528 * sb_start_pagefault - get write access to a superblock from a page fault
1529 * @sb: the super we write to
1531 * When a process starts handling write page fault, it should embed the
1532 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1533 * exclusion against file system freezing. This is needed since the page fault
1534 * is going to dirty a page. This function increments number of running page
1535 * faults preventing freezing. If the file system is already frozen, the
1536 * function waits until the file system is thawed.
1538 * Since page fault freeze protection behaves as a lock, users have to preserve
1539 * ordering of freeze protection and other filesystem locks. It is advised to
1540 * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
1541 * handling code implies lock dependency:
1544 * -> sb_start_pagefault
1546 static inline void sb_start_pagefault(struct super_block *sb)
1548 __sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
1552 * sb_start_intwrite - get write access to a superblock for internal fs purposes
1553 * @sb: the super we write to
1555 * This is the third level of protection against filesystem freezing. It is
1556 * free for use by a filesystem. The only requirement is that it must rank
1557 * below sb_start_pagefault.
1559 * For example filesystem can call sb_start_intwrite() when starting a
1560 * transaction which somewhat eases handling of freezing for internal sources
1561 * of filesystem changes (internal fs threads, discarding preallocation on file
1564 static inline void sb_start_intwrite(struct super_block *sb)
1566 __sb_start_write(sb, SB_FREEZE_FS, true);
1570 extern bool inode_owner_or_capable(const struct inode *inode);
1573 * VFS helper functions..
1575 extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
1576 extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
1577 extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
1578 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
1579 extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
1580 extern int vfs_rmdir(struct inode *, struct dentry *);
1581 extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
1582 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
1583 extern int vfs_whiteout(struct inode *, struct dentry *);
1586 * VFS file helper functions.
1588 extern void inode_init_owner(struct inode *inode, const struct inode *dir,
1591 * VFS FS_IOC_FIEMAP helper definitions.
1593 struct fiemap_extent_info {
1594 unsigned int fi_flags; /* Flags as passed from user */
1595 unsigned int fi_extents_mapped; /* Number of mapped extents */
1596 unsigned int fi_extents_max; /* Size of fiemap_extent array */
1597 struct fiemap_extent __user *fi_extents_start; /* Start of
1598 fiemap_extent array */
1600 int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
1601 u64 phys, u64 len, u32 flags);
1602 int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
1607 * NOTE! These match bits 12..15 of stat.st_mode
1608 * (ie "(i_mode >> 12) & 15").
1610 #define DT_UNKNOWN 0
1621 * This is the "filldir" function type, used by readdir() to let
1622 * the kernel specify what kind of dirent layout it wants to have.
1623 * This allows the kernel to read directories into kernel space or
1624 * to have different dirent layouts depending on the binary type.
1627 typedef int (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
1630 struct dir_context {
1631 const filldir_t actor;
1635 struct block_device_operations;
1637 /* These macros are for out of kernel modules to test that
1638 * the kernel supports the unlocked_ioctl and compat_ioctl
1639 * fields in struct file_operations. */
1640 #define HAVE_COMPAT_IOCTL 1
1641 #define HAVE_UNLOCKED_IOCTL 1
1644 * These flags let !MMU mmap() govern direct device mapping vs immediate
1645 * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
1647 * NOMMU_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
1648 * NOMMU_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
1649 * NOMMU_MAP_READ: Can be mapped for reading
1650 * NOMMU_MAP_WRITE: Can be mapped for writing
1651 * NOMMU_MAP_EXEC: Can be mapped for execution
1653 #define NOMMU_MAP_COPY 0x00000001
1654 #define NOMMU_MAP_DIRECT 0x00000008
1655 #define NOMMU_MAP_READ VM_MAYREAD
1656 #define NOMMU_MAP_WRITE VM_MAYWRITE
1657 #define NOMMU_MAP_EXEC VM_MAYEXEC
1659 #define NOMMU_VMFLAGS \
1660 (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC)
1665 struct file_operations {
1666 struct module *owner;
1667 loff_t (*llseek) (struct file *, loff_t, int);
1668 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1669 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1670 ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1671 ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1672 int (*iterate) (struct file *, struct dir_context *);
1673 int (*iterate_shared) (struct file *, struct dir_context *);
1674 unsigned int (*poll) (struct file *, struct poll_table_struct *);
1675 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1676 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1677 int (*mmap) (struct file *, struct vm_area_struct *);
1678 int (*open) (struct inode *, struct file *);
1679 int (*flush) (struct file *, fl_owner_t id);
1680 int (*release) (struct inode *, struct file *);
1681 int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1682 int (*aio_fsync) (struct kiocb *, int datasync);
1683 int (*fasync) (int, struct file *, int);
1684 int (*lock) (struct file *, int, struct file_lock *);
1685 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1686 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1687 int (*check_flags)(int);
1688 int (*flock) (struct file *, int, struct file_lock *);
1689 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1690 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1691 int (*setlease)(struct file *, long, struct file_lock **, void **);
1692 long (*fallocate)(struct file *file, int mode, loff_t offset,
1694 void (*show_fdinfo)(struct seq_file *m, struct file *f);
1696 unsigned (*mmap_capabilities)(struct file *);
1698 ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,
1699 loff_t, size_t, unsigned int);
1700 int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t,
1702 ssize_t (*dedupe_file_range)(struct file *, u64, u64, struct file *,
1706 struct inode_operations {
1707 struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1708 const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
1709 int (*permission) (struct inode *, int);
1710 struct posix_acl * (*get_acl)(struct inode *, int);
1712 int (*readlink) (struct dentry *, char __user *,int);
1714 int (*create) (struct inode *,struct dentry *, umode_t, bool);
1715 int (*link) (struct dentry *,struct inode *,struct dentry *);
1716 int (*unlink) (struct inode *,struct dentry *);
1717 int (*symlink) (struct inode *,struct dentry *,const char *);
1718 int (*mkdir) (struct inode *,struct dentry *,umode_t);
1719 int (*rmdir) (struct inode *,struct dentry *);
1720 int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
1721 int (*rename) (struct inode *, struct dentry *,
1722 struct inode *, struct dentry *);
1723 int (*rename2) (struct inode *, struct dentry *,
1724 struct inode *, struct dentry *, unsigned int);
1725 int (*setattr) (struct dentry *, struct iattr *);
1726 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1727 int (*setxattr) (struct dentry *, struct inode *,
1728 const char *, const void *, size_t, int);
1729 ssize_t (*getxattr) (struct dentry *, struct inode *,
1730 const char *, void *, size_t);
1731 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1732 int (*removexattr) (struct dentry *, const char *);
1733 int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1735 int (*update_time)(struct inode *, struct timespec *, int);
1736 int (*atomic_open)(struct inode *, struct dentry *,
1737 struct file *, unsigned open_flag,
1738 umode_t create_mode, int *opened);
1739 int (*tmpfile) (struct inode *, struct dentry *, umode_t);
1740 int (*set_acl)(struct inode *, struct posix_acl *, int);
1741 } ____cacheline_aligned;
1743 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1744 unsigned long nr_segs, unsigned long fast_segs,
1745 struct iovec *fast_pointer,
1746 struct iovec **ret_pointer);
1748 extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
1749 extern ssize_t __vfs_write(struct file *, const char __user *, size_t, loff_t *);
1750 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1751 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1752 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1753 unsigned long, loff_t *, int);
1754 extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1755 unsigned long, loff_t *, int);
1756 extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
1757 loff_t, size_t, unsigned int);
1758 extern int vfs_clone_file_range(struct file *file_in, loff_t pos_in,
1759 struct file *file_out, loff_t pos_out, u64 len);
1760 extern int vfs_dedupe_file_range(struct file *file,
1761 struct file_dedupe_range *same);
1763 struct super_operations {
1764 struct inode *(*alloc_inode)(struct super_block *sb);
1765 void (*destroy_inode)(struct inode *);
1767 void (*dirty_inode) (struct inode *, int flags);
1768 int (*write_inode) (struct inode *, struct writeback_control *wbc);
1769 int (*drop_inode) (struct inode *);
1770 void (*evict_inode) (struct inode *);
1771 void (*put_super) (struct super_block *);
1772 int (*sync_fs)(struct super_block *sb, int wait);
1773 int (*freeze_super) (struct super_block *);
1774 int (*freeze_fs) (struct super_block *);
1775 int (*thaw_super) (struct super_block *);
1776 int (*unfreeze_fs) (struct super_block *);
1777 int (*statfs) (struct dentry *, struct kstatfs *);
1778 int (*remount_fs) (struct super_block *, int *, char *);
1779 void (*umount_begin) (struct super_block *);
1781 int (*show_options)(struct seq_file *, struct dentry *);
1782 int (*show_devname)(struct seq_file *, struct dentry *);
1783 int (*show_path)(struct seq_file *, struct dentry *);
1784 int (*show_stats)(struct seq_file *, struct dentry *);
1786 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1787 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1788 struct dquot **(*get_dquots)(struct inode *);
1790 int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
1791 long (*nr_cached_objects)(struct super_block *,
1792 struct shrink_control *);
1793 long (*free_cached_objects)(struct super_block *,
1794 struct shrink_control *);
1798 * Inode flags - they have no relation to superblock flags now
1800 #define S_SYNC 1 /* Writes are synced at once */
1801 #define S_NOATIME 2 /* Do not update access times */
1802 #define S_APPEND 4 /* Append-only file */
1803 #define S_IMMUTABLE 8 /* Immutable file */
1804 #define S_DEAD 16 /* removed, but still open directory */
1805 #define S_NOQUOTA 32 /* Inode is not counted to quota */
1806 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
1807 #define S_NOCMTIME 128 /* Do not update file c/mtime */
1808 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
1809 #define S_PRIVATE 512 /* Inode is fs-internal */
1810 #define S_IMA 1024 /* Inode has an associated IMA struct */
1811 #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
1812 #define S_NOSEC 4096 /* no suid or xattr security attributes */
1813 #ifdef CONFIG_FS_DAX
1814 #define S_DAX 8192 /* Direct Access, avoiding the page cache */
1816 #define S_DAX 0 /* Make all the DAX code disappear */
1820 * Note that nosuid etc flags are inode-specific: setting some file-system
1821 * flags just means all the inodes inherit those flags by default. It might be
1822 * possible to override it selectively if you really wanted to with some
1823 * ioctl() that is not currently implemented.
1825 * Exception: MS_RDONLY is always applied to the entire file system.
1827 * Unfortunately, it is possible to change a filesystems flags with it mounted
1828 * with files in use. This means that all of the inodes will not have their
1829 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1830 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1832 #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1834 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
1835 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
1836 ((inode)->i_flags & S_SYNC))
1837 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
1838 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1839 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
1840 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
1841 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
1843 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1844 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1845 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1846 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
1848 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1849 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1850 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1851 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1852 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1853 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1854 #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
1855 #define IS_DAX(inode) ((inode)->i_flags & S_DAX)
1857 #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
1858 (inode)->i_rdev == WHITEOUT_DEV)
1861 * Inode state bits. Protected by inode->i_lock
1863 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
1864 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
1866 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
1867 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
1868 * various stages of removing an inode.
1870 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
1872 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
1873 * fdatasync(). i_atime is the usual cause.
1874 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
1875 * these changes separately from I_DIRTY_SYNC so that we
1876 * don't have to write inode on fdatasync() when only
1877 * mtime has changed in it.
1878 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
1879 * I_NEW Serves as both a mutex and completion notification.
1880 * New inodes set I_NEW. If two processes both create
1881 * the same inode, one of them will release its inode and
1882 * wait for I_NEW to be released before returning.
1883 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
1884 * also cause waiting on I_NEW, without I_NEW actually
1885 * being set. find_inode() uses this to prevent returning
1886 * nearly-dead inodes.
1887 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
1888 * is zero. I_FREEING must be set when I_WILL_FREE is
1890 * I_FREEING Set when inode is about to be freed but still has dirty
1891 * pages or buffers attached or the inode itself is still
1893 * I_CLEAR Added by clear_inode(). In this state the inode is
1894 * clean and can be destroyed. Inode keeps I_FREEING.
1896 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
1897 * prohibited for many purposes. iget() must wait for
1898 * the inode to be completely released, then create it
1899 * anew. Other functions will just ignore such inodes,
1900 * if appropriate. I_NEW is used for waiting.
1902 * I_SYNC Writeback of inode is running. The bit is set during
1903 * data writeback, and cleared with a wakeup on the bit
1904 * address once it is done. The bit is also used to pin
1905 * the inode in memory for flusher thread.
1907 * I_REFERENCED Marks the inode as recently references on the LRU list.
1909 * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
1911 * I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
1912 * synchronize competing switching instances and to tell
1913 * wb stat updates to grab mapping->tree_lock. See
1914 * inode_switch_wb_work_fn() for details.
1916 * Q: What is the difference between I_WILL_FREE and I_FREEING?
1918 #define I_DIRTY_SYNC (1 << 0)
1919 #define I_DIRTY_DATASYNC (1 << 1)
1920 #define I_DIRTY_PAGES (1 << 2)
1922 #define I_NEW (1 << __I_NEW)
1923 #define I_WILL_FREE (1 << 4)
1924 #define I_FREEING (1 << 5)
1925 #define I_CLEAR (1 << 6)
1927 #define I_SYNC (1 << __I_SYNC)
1928 #define I_REFERENCED (1 << 8)
1929 #define __I_DIO_WAKEUP 9
1930 #define I_DIO_WAKEUP (1 << __I_DIO_WAKEUP)
1931 #define I_LINKABLE (1 << 10)
1932 #define I_DIRTY_TIME (1 << 11)
1933 #define __I_DIRTY_TIME_EXPIRED 12
1934 #define I_DIRTY_TIME_EXPIRED (1 << __I_DIRTY_TIME_EXPIRED)
1935 #define I_WB_SWITCH (1 << 13)
1937 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1938 #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
1940 extern void __mark_inode_dirty(struct inode *, int);
1941 static inline void mark_inode_dirty(struct inode *inode)
1943 __mark_inode_dirty(inode, I_DIRTY);
1946 static inline void mark_inode_dirty_sync(struct inode *inode)
1948 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1951 extern void inc_nlink(struct inode *inode);
1952 extern void drop_nlink(struct inode *inode);
1953 extern void clear_nlink(struct inode *inode);
1954 extern void set_nlink(struct inode *inode, unsigned int nlink);
1956 static inline void inode_inc_link_count(struct inode *inode)
1959 mark_inode_dirty(inode);
1962 static inline void inode_dec_link_count(struct inode *inode)
1965 mark_inode_dirty(inode);
1969 * inode_inc_iversion - increments i_version
1970 * @inode: inode that need to be updated
1972 * Every time the inode is modified, the i_version field will be incremented.
1973 * The filesystem has to be mounted with i_version flag
1976 static inline void inode_inc_iversion(struct inode *inode)
1978 spin_lock(&inode->i_lock);
1980 spin_unlock(&inode->i_lock);
1983 enum file_time_flags {
1990 extern bool atime_needs_update(const struct path *, struct inode *);
1991 extern void touch_atime(const struct path *);
1992 static inline void file_accessed(struct file *file)
1994 if (!(file->f_flags & O_NOATIME))
1995 touch_atime(&file->f_path);
1998 int sync_inode(struct inode *inode, struct writeback_control *wbc);
1999 int sync_inode_metadata(struct inode *inode, int wait);
2001 struct file_system_type {
2004 #define FS_REQUIRES_DEV 1
2005 #define FS_BINARY_MOUNTDATA 2
2006 #define FS_HAS_SUBTYPE 4
2007 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
2008 #define FS_USERNS_DEV_MOUNT 16 /* A userns mount does not imply MNT_NODEV */
2009 #define FS_USERNS_VISIBLE 32 /* FS must already be visible */
2010 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
2011 struct dentry *(*mount) (struct file_system_type *, int,
2012 const char *, void *);
2013 void (*kill_sb) (struct super_block *);
2014 struct module *owner;
2015 struct file_system_type * next;
2016 struct hlist_head fs_supers;
2018 struct lock_class_key s_lock_key;
2019 struct lock_class_key s_umount_key;
2020 struct lock_class_key s_vfs_rename_key;
2021 struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
2023 struct lock_class_key i_lock_key;
2024 struct lock_class_key i_mutex_key;
2025 struct lock_class_key i_mutex_dir_key;
2028 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
2030 extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
2031 void *data, int (*fill_super)(struct super_block *, void *, int));
2032 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
2033 int flags, const char *dev_name, void *data,
2034 int (*fill_super)(struct super_block *, void *, int));
2035 extern struct dentry *mount_single(struct file_system_type *fs_type,
2036 int flags, void *data,
2037 int (*fill_super)(struct super_block *, void *, int));
2038 extern struct dentry *mount_nodev(struct file_system_type *fs_type,
2039 int flags, void *data,
2040 int (*fill_super)(struct super_block *, void *, int));
2041 extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
2042 void generic_shutdown_super(struct super_block *sb);
2043 void kill_block_super(struct super_block *sb);
2044 void kill_anon_super(struct super_block *sb);
2045 void kill_litter_super(struct super_block *sb);
2046 void deactivate_super(struct super_block *sb);
2047 void deactivate_locked_super(struct super_block *sb);
2048 int set_anon_super(struct super_block *s, void *data);
2049 int get_anon_bdev(dev_t *);
2050 void free_anon_bdev(dev_t);
2051 struct super_block *sget(struct file_system_type *type,
2052 int (*test)(struct super_block *,void *),
2053 int (*set)(struct super_block *,void *),
2054 int flags, void *data);
2055 extern struct dentry *mount_pseudo(struct file_system_type *, char *,
2056 const struct super_operations *ops,
2057 const struct dentry_operations *dops,
2060 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
2061 #define fops_get(fops) \
2062 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
2063 #define fops_put(fops) \
2064 do { if (fops) module_put((fops)->owner); } while(0)
2066 * This one is to be used *ONLY* from ->open() instances.
2067 * fops must be non-NULL, pinned down *and* module dependencies
2068 * should be sufficient to pin the caller down as well.
2070 #define replace_fops(f, fops) \
2072 struct file *__file = (f); \
2073 fops_put(__file->f_op); \
2074 BUG_ON(!(__file->f_op = (fops))); \
2077 extern int register_filesystem(struct file_system_type *);
2078 extern int unregister_filesystem(struct file_system_type *);
2079 extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
2080 #define kern_mount(type) kern_mount_data(type, NULL)
2081 extern void kern_unmount(struct vfsmount *mnt);
2082 extern int may_umount_tree(struct vfsmount *);
2083 extern int may_umount(struct vfsmount *);
2084 extern long do_mount(const char *, const char __user *,
2085 const char *, unsigned long, void *);
2086 extern struct vfsmount *collect_mounts(struct path *);
2087 extern void drop_collected_mounts(struct vfsmount *);
2088 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
2090 extern int vfs_statfs(struct path *, struct kstatfs *);
2091 extern int user_statfs(const char __user *, struct kstatfs *);
2092 extern int fd_statfs(int, struct kstatfs *);
2093 extern int vfs_ustat(dev_t, struct kstatfs *);
2094 extern int freeze_super(struct super_block *super);
2095 extern int thaw_super(struct super_block *super);
2096 extern bool our_mnt(struct vfsmount *mnt);
2098 extern int current_umask(void);
2100 extern void ihold(struct inode * inode);
2101 extern void iput(struct inode *);
2102 extern int generic_update_time(struct inode *, struct timespec *, int);
2105 extern struct kobject *fs_kobj;
2107 #define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
2109 #ifdef CONFIG_MANDATORY_FILE_LOCKING
2110 extern int locks_mandatory_locked(struct file *);
2111 extern int locks_mandatory_area(struct inode *, struct file *, loff_t, loff_t, unsigned char);
2114 * Candidates for mandatory locking have the setgid bit set
2115 * but no group execute bit - an otherwise meaningless combination.
2118 static inline int __mandatory_lock(struct inode *ino)
2120 return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
2124 * ... and these candidates should be on MS_MANDLOCK mounted fs,
2125 * otherwise these will be advisory locks
2128 static inline int mandatory_lock(struct inode *ino)
2130 return IS_MANDLOCK(ino) && __mandatory_lock(ino);
2133 static inline int locks_verify_locked(struct file *file)
2135 if (mandatory_lock(file_inode(file)))
2136 return locks_mandatory_locked(file);
2140 static inline int locks_verify_truncate(struct inode *inode,
2144 if (!inode->i_flctx || !mandatory_lock(inode))
2147 if (size < inode->i_size) {
2148 return locks_mandatory_area(inode, f, size, inode->i_size - 1,
2151 return locks_mandatory_area(inode, f, inode->i_size, size - 1,
2156 #else /* !CONFIG_MANDATORY_FILE_LOCKING */
2158 static inline int locks_mandatory_locked(struct file *file)
2163 static inline int locks_mandatory_area(struct inode *inode, struct file *filp,
2164 loff_t start, loff_t end, unsigned char type)
2169 static inline int __mandatory_lock(struct inode *inode)
2174 static inline int mandatory_lock(struct inode *inode)
2179 static inline int locks_verify_locked(struct file *file)
2184 static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
2190 #endif /* CONFIG_MANDATORY_FILE_LOCKING */
2193 #ifdef CONFIG_FILE_LOCKING
2194 static inline int break_lease(struct inode *inode, unsigned int mode)
2197 * Since this check is lockless, we must ensure that any refcounts
2198 * taken are done before checking i_flctx->flc_lease. Otherwise, we
2199 * could end up racing with tasks trying to set a new lease on this
2203 if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2204 return __break_lease(inode, mode, FL_LEASE);
2208 static inline int break_deleg(struct inode *inode, unsigned int mode)
2211 * Since this check is lockless, we must ensure that any refcounts
2212 * taken are done before checking i_flctx->flc_lease. Otherwise, we
2213 * could end up racing with tasks trying to set a new lease on this
2217 if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2218 return __break_lease(inode, mode, FL_DELEG);
2222 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2226 ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
2227 if (ret == -EWOULDBLOCK && delegated_inode) {
2228 *delegated_inode = inode;
2234 static inline int break_deleg_wait(struct inode **delegated_inode)
2238 ret = break_deleg(*delegated_inode, O_WRONLY);
2239 iput(*delegated_inode);
2240 *delegated_inode = NULL;
2244 static inline int break_layout(struct inode *inode, bool wait)
2247 if (inode->i_flctx && !list_empty_careful(&inode->i_flctx->flc_lease))
2248 return __break_lease(inode,
2249 wait ? O_WRONLY : O_WRONLY | O_NONBLOCK,
2254 #else /* !CONFIG_FILE_LOCKING */
2255 static inline int break_lease(struct inode *inode, unsigned int mode)
2260 static inline int break_deleg(struct inode *inode, unsigned int mode)
2265 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2270 static inline int break_deleg_wait(struct inode **delegated_inode)
2276 static inline int break_layout(struct inode *inode, bool wait)
2281 #endif /* CONFIG_FILE_LOCKING */
2286 const char *name; /* pointer to actual string */
2287 const __user char *uptr; /* original userland pointer */
2288 struct audit_names *aname;
2293 extern long vfs_truncate(const struct path *, loff_t);
2294 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
2296 extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
2298 extern long do_sys_open(int dfd, const char __user *filename, int flags,
2300 extern struct file *file_open_name(struct filename *, int, umode_t);
2301 extern struct file *filp_open(const char *, int, umode_t);
2302 extern struct file *file_open_root(struct dentry *, struct vfsmount *,
2303 const char *, int, umode_t);
2304 extern struct file * dentry_open(const struct path *, int, const struct cred *);
2305 extern int filp_close(struct file *, fl_owner_t id);
2307 extern struct filename *getname_flags(const char __user *, int, int *);
2308 extern struct filename *getname(const char __user *);
2309 extern struct filename *getname_kernel(const char *);
2310 extern void putname(struct filename *name);
2316 extern int finish_open(struct file *file, struct dentry *dentry,
2317 int (*open)(struct inode *, struct file *),
2319 extern int finish_no_open(struct file *file, struct dentry *dentry);
2323 extern int ioctl_preallocate(struct file *filp, void __user *argp);
2326 extern void __init vfs_caches_init_early(void);
2327 extern void __init vfs_caches_init(void);
2329 extern struct kmem_cache *names_cachep;
2331 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2332 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2335 extern int register_blkdev(unsigned int, const char *);
2336 extern void unregister_blkdev(unsigned int, const char *);
2337 extern struct block_device *bdget(dev_t);
2338 extern struct block_device *bdgrab(struct block_device *bdev);
2339 extern void bd_set_size(struct block_device *, loff_t size);
2340 extern void bd_forget(struct inode *inode);
2341 extern void bdput(struct block_device *);
2342 extern void invalidate_bdev(struct block_device *);
2343 extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
2344 extern int sync_blockdev(struct block_device *bdev);
2345 extern void kill_bdev(struct block_device *);
2346 extern struct super_block *freeze_bdev(struct block_device *);
2347 extern void emergency_thaw_all(void);
2348 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
2349 extern int fsync_bdev(struct block_device *);
2351 extern struct super_block *blockdev_superblock;
2353 static inline bool sb_is_blkdev_sb(struct super_block *sb)
2355 return sb == blockdev_superblock;
2358 static inline void bd_forget(struct inode *inode) {}
2359 static inline int sync_blockdev(struct block_device *bdev) { return 0; }
2360 static inline void kill_bdev(struct block_device *bdev) {}
2361 static inline void invalidate_bdev(struct block_device *bdev) {}
2363 static inline struct super_block *freeze_bdev(struct block_device *sb)
2368 static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
2373 static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
2377 static inline bool sb_is_blkdev_sb(struct super_block *sb)
2382 extern int sync_filesystem(struct super_block *);
2383 extern const struct file_operations def_blk_fops;
2384 extern const struct file_operations def_chr_fops;
2386 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
2387 extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
2388 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
2389 extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
2390 extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
2392 extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
2394 extern void blkdev_put(struct block_device *bdev, fmode_t mode);
2395 extern int __blkdev_reread_part(struct block_device *bdev);
2396 extern int blkdev_reread_part(struct block_device *bdev);
2399 extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
2400 extern void bd_unlink_disk_holder(struct block_device *bdev,
2401 struct gendisk *disk);
2403 static inline int bd_link_disk_holder(struct block_device *bdev,
2404 struct gendisk *disk)
2408 static inline void bd_unlink_disk_holder(struct block_device *bdev,
2409 struct gendisk *disk)
2416 #define CHRDEV_MAJOR_HASH_SIZE 255
2417 /* Marks the bottom of the first segment of free char majors */
2418 #define CHRDEV_MAJOR_DYN_END 234
2419 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2420 extern int register_chrdev_region(dev_t, unsigned, const char *);
2421 extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2422 unsigned int count, const char *name,
2423 const struct file_operations *fops);
2424 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2425 unsigned int count, const char *name);
2426 extern void unregister_chrdev_region(dev_t, unsigned);
2427 extern void chrdev_show(struct seq_file *,off_t);
2429 static inline int register_chrdev(unsigned int major, const char *name,
2430 const struct file_operations *fops)
2432 return __register_chrdev(major, 0, 256, name, fops);
2435 static inline void unregister_chrdev(unsigned int major, const char *name)
2437 __unregister_chrdev(major, 0, 256, name);
2440 /* fs/block_dev.c */
2441 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
2442 #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
2445 #define BLKDEV_MAJOR_HASH_SIZE 255
2446 extern const char *__bdevname(dev_t, char *buffer);
2447 extern const char *bdevname(struct block_device *bdev, char *buffer);
2448 extern struct block_device *lookup_bdev(const char *);
2449 extern void blkdev_show(struct seq_file *,off_t);
2452 #define BLKDEV_MAJOR_HASH_SIZE 0
2455 extern void init_special_inode(struct inode *, umode_t, dev_t);
2457 /* Invalid inode operations -- fs/bad_inode.c */
2458 extern void make_bad_inode(struct inode *);
2459 extern bool is_bad_inode(struct inode *);
2463 * return READ, READA, or WRITE
2465 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
2468 * return data direction, READ or WRITE
2470 #define bio_data_dir(bio) ((bio)->bi_rw & 1)
2472 extern void check_disk_size_change(struct gendisk *disk,
2473 struct block_device *bdev);
2474 extern int revalidate_disk(struct gendisk *);
2475 extern int check_disk_change(struct block_device *);
2476 extern int __invalidate_device(struct block_device *, bool);
2477 extern int invalidate_partition(struct gendisk *, int);
2479 unsigned long invalidate_mapping_pages(struct address_space *mapping,
2480 pgoff_t start, pgoff_t end);
2482 static inline void invalidate_remote_inode(struct inode *inode)
2484 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2485 S_ISLNK(inode->i_mode))
2486 invalidate_mapping_pages(inode->i_mapping, 0, -1);
2488 extern int invalidate_inode_pages2(struct address_space *mapping);
2489 extern int invalidate_inode_pages2_range(struct address_space *mapping,
2490 pgoff_t start, pgoff_t end);
2491 extern int write_inode_now(struct inode *, int);
2492 extern int filemap_fdatawrite(struct address_space *);
2493 extern int filemap_flush(struct address_space *);
2494 extern int filemap_fdatawait(struct address_space *);
2495 extern void filemap_fdatawait_keep_errors(struct address_space *);
2496 extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
2498 extern int filemap_write_and_wait(struct address_space *mapping);
2499 extern int filemap_write_and_wait_range(struct address_space *mapping,
2500 loff_t lstart, loff_t lend);
2501 extern int __filemap_fdatawrite_range(struct address_space *mapping,
2502 loff_t start, loff_t end, int sync_mode);
2503 extern int filemap_fdatawrite_range(struct address_space *mapping,
2504 loff_t start, loff_t end);
2506 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2508 extern int vfs_fsync(struct file *file, int datasync);
2511 * Sync the bytes written if this was a synchronous write. Expect ki_pos
2512 * to already be updated for the write, and will return either the amount
2513 * of bytes passed in, or an error if syncing the file failed.
2515 static inline ssize_t generic_write_sync(struct kiocb *iocb, ssize_t count)
2517 if (iocb->ki_flags & IOCB_DSYNC) {
2518 int ret = vfs_fsync_range(iocb->ki_filp,
2519 iocb->ki_pos - count, iocb->ki_pos - 1,
2520 (iocb->ki_flags & IOCB_SYNC) ? 0 : 1);
2528 extern void emergency_sync(void);
2529 extern void emergency_remount(void);
2531 extern sector_t bmap(struct inode *, sector_t);
2533 extern int notify_change(struct dentry *, struct iattr *, struct inode **);
2534 extern int inode_permission(struct inode *, int);
2535 extern int __inode_permission(struct inode *, int);
2536 extern int generic_permission(struct inode *, int);
2537 extern int __check_sticky(struct inode *dir, struct inode *inode);
2539 static inline bool execute_ok(struct inode *inode)
2541 return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2544 static inline void file_start_write(struct file *file)
2546 if (!S_ISREG(file_inode(file)->i_mode))
2548 __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
2551 static inline bool file_start_write_trylock(struct file *file)
2553 if (!S_ISREG(file_inode(file)->i_mode))
2555 return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
2558 static inline void file_end_write(struct file *file)
2560 if (!S_ISREG(file_inode(file)->i_mode))
2562 __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2566 * get_write_access() gets write permission for a file.
2567 * put_write_access() releases this write permission.
2568 * This is used for regular files.
2569 * We cannot support write (and maybe mmap read-write shared) accesses and
2570 * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
2571 * can have the following values:
2572 * 0: no writers, no VM_DENYWRITE mappings
2573 * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
2574 * > 0: (i_writecount) users are writing to the file.
2576 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2577 * except for the cases where we don't hold i_writecount yet. Then we need to
2578 * use {get,deny}_write_access() - these functions check the sign and refuse
2579 * to do the change if sign is wrong.
2581 static inline int get_write_access(struct inode *inode)
2583 return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2585 static inline int deny_write_access(struct file *file)
2587 struct inode *inode = file_inode(file);
2588 return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2590 static inline void put_write_access(struct inode * inode)
2592 atomic_dec(&inode->i_writecount);
2594 static inline void allow_write_access(struct file *file)
2597 atomic_inc(&file_inode(file)->i_writecount);
2599 static inline bool inode_is_open_for_write(const struct inode *inode)
2601 return atomic_read(&inode->i_writecount) > 0;
2605 static inline void i_readcount_dec(struct inode *inode)
2607 BUG_ON(!atomic_read(&inode->i_readcount));
2608 atomic_dec(&inode->i_readcount);
2610 static inline void i_readcount_inc(struct inode *inode)
2612 atomic_inc(&inode->i_readcount);
2615 static inline void i_readcount_dec(struct inode *inode)
2619 static inline void i_readcount_inc(struct inode *inode)
2624 extern int do_pipe_flags(int *, int);
2626 #define __kernel_read_file_id(id) \
2627 id(UNKNOWN, unknown) \
2628 id(FIRMWARE, firmware) \
2629 id(MODULE, kernel-module) \
2630 id(KEXEC_IMAGE, kexec-image) \
2631 id(KEXEC_INITRAMFS, kexec-initramfs) \
2632 id(POLICY, security-policy) \
2635 #define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
2636 #define __fid_stringify(dummy, str) #str,
2638 enum kernel_read_file_id {
2639 __kernel_read_file_id(__fid_enumify)
2642 static const char * const kernel_read_file_str[] = {
2643 __kernel_read_file_id(__fid_stringify)
2646 static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id)
2648 if (id < 0 || id >= READING_MAX_ID)
2649 return kernel_read_file_str[READING_UNKNOWN];
2651 return kernel_read_file_str[id];
2654 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
2655 extern int kernel_read_file(struct file *, void **, loff_t *, loff_t,
2656 enum kernel_read_file_id);
2657 extern int kernel_read_file_from_path(char *, void **, loff_t *, loff_t,
2658 enum kernel_read_file_id);
2659 extern int kernel_read_file_from_fd(int, void **, loff_t *, loff_t,
2660 enum kernel_read_file_id);
2661 extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
2662 extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
2663 extern struct file * open_exec(const char *);
2665 /* fs/dcache.c -- generic fs support functions */
2666 extern bool is_subdir(struct dentry *, struct dentry *);
2667 extern bool path_is_under(struct path *, struct path *);
2669 extern char *file_path(struct file *, char *, int);
2671 #include <linux/err.h>
2673 /* needed for stackable file system support */
2674 extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2676 extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2678 extern int inode_init_always(struct super_block *, struct inode *);
2679 extern void inode_init_once(struct inode *);
2680 extern void address_space_init_once(struct address_space *mapping);
2681 extern struct inode * igrab(struct inode *);
2682 extern ino_t iunique(struct super_block *, ino_t);
2683 extern int inode_needs_sync(struct inode *inode);
2684 extern int generic_delete_inode(struct inode *inode);
2685 static inline int generic_drop_inode(struct inode *inode)
2687 return !inode->i_nlink || inode_unhashed(inode);
2690 extern struct inode *ilookup5_nowait(struct super_block *sb,
2691 unsigned long hashval, int (*test)(struct inode *, void *),
2693 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2694 int (*test)(struct inode *, void *), void *data);
2695 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2697 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2698 extern struct inode * iget_locked(struct super_block *, unsigned long);
2699 extern struct inode *find_inode_nowait(struct super_block *,
2701 int (*match)(struct inode *,
2702 unsigned long, void *),
2704 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2705 extern int insert_inode_locked(struct inode *);
2706 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2707 extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2709 static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2711 extern void unlock_new_inode(struct inode *);
2712 extern unsigned int get_next_ino(void);
2714 extern void __iget(struct inode * inode);
2715 extern void iget_failed(struct inode *);
2716 extern void clear_inode(struct inode *);
2717 extern void __destroy_inode(struct inode *);
2718 extern struct inode *new_inode_pseudo(struct super_block *sb);
2719 extern struct inode *new_inode(struct super_block *sb);
2720 extern void free_inode_nonrcu(struct inode *inode);
2721 extern int should_remove_suid(struct dentry *);
2722 extern int file_remove_privs(struct file *);
2723 extern int dentry_needs_remove_privs(struct dentry *dentry);
2724 static inline int file_needs_remove_privs(struct file *file)
2726 return dentry_needs_remove_privs(file->f_path.dentry);
2729 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2730 static inline void insert_inode_hash(struct inode *inode)
2732 __insert_inode_hash(inode, inode->i_ino);
2735 extern void __remove_inode_hash(struct inode *);
2736 static inline void remove_inode_hash(struct inode *inode)
2738 if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
2739 __remove_inode_hash(inode);
2742 extern void inode_sb_list_add(struct inode *inode);
2745 extern blk_qc_t submit_bio(int, struct bio *);
2746 extern int bdev_read_only(struct block_device *);
2748 extern int set_blocksize(struct block_device *, int);
2749 extern int sb_set_blocksize(struct super_block *, int);
2750 extern int sb_min_blocksize(struct super_block *, int);
2752 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2753 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2754 extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
2755 extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2756 extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
2757 extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
2758 extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *);
2759 extern ssize_t generic_perform_write(struct file *, struct iov_iter *, loff_t);
2761 ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos);
2762 ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos);
2764 /* fs/block_dev.c */
2765 extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);
2766 extern ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from);
2767 extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
2769 extern void block_sync_page(struct page *page);
2772 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
2773 struct pipe_inode_info *, size_t, unsigned int);
2774 extern ssize_t default_file_splice_read(struct file *, loff_t *,
2775 struct pipe_inode_info *, size_t, unsigned int);
2776 extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
2777 struct file *, loff_t *, size_t, unsigned int);
2778 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2779 struct file *out, loff_t *, size_t len, unsigned int flags);
2780 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
2781 loff_t *opos, size_t len, unsigned int flags);
2785 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2786 extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
2787 extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
2788 extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
2789 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
2790 extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
2791 int whence, loff_t maxsize, loff_t eof);
2792 extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
2793 int whence, loff_t size);
2794 extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);
2795 extern loff_t no_seek_end_llseek(struct file *, loff_t, int);
2796 extern int generic_file_open(struct inode * inode, struct file * filp);
2797 extern int nonseekable_open(struct inode * inode, struct file * filp);
2800 typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
2801 loff_t file_offset);
2804 /* need locking between buffered and direct access */
2807 /* filesystem does not support filling holes */
2808 DIO_SKIP_HOLES = 0x02,
2810 /* filesystem can handle aio writes beyond i_size */
2811 DIO_ASYNC_EXTEND = 0x04,
2813 /* inode/fs/bdev does not need truncate protection */
2814 DIO_SKIP_DIO_COUNT = 0x08,
2817 void dio_end_io(struct bio *bio, int error);
2819 ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
2820 struct block_device *bdev, struct iov_iter *iter,
2821 get_block_t get_block,
2822 dio_iodone_t end_io, dio_submit_t submit_io,
2825 static inline ssize_t blockdev_direct_IO(struct kiocb *iocb,
2826 struct inode *inode,
2827 struct iov_iter *iter,
2828 get_block_t get_block)
2830 return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
2831 get_block, NULL, NULL, DIO_LOCKING | DIO_SKIP_HOLES);
2835 void inode_dio_wait(struct inode *inode);
2838 * inode_dio_begin - signal start of a direct I/O requests
2839 * @inode: inode the direct I/O happens on
2841 * This is called once we've finished processing a direct I/O request,
2842 * and is used to wake up callers waiting for direct I/O to be quiesced.
2844 static inline void inode_dio_begin(struct inode *inode)
2846 atomic_inc(&inode->i_dio_count);
2850 * inode_dio_end - signal finish of a direct I/O requests
2851 * @inode: inode the direct I/O happens on
2853 * This is called once we've finished processing a direct I/O request,
2854 * and is used to wake up callers waiting for direct I/O to be quiesced.
2856 static inline void inode_dio_end(struct inode *inode)
2858 if (atomic_dec_and_test(&inode->i_dio_count))
2859 wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
2862 extern void inode_set_flags(struct inode *inode, unsigned int flags,
2865 extern const struct file_operations generic_ro_fops;
2867 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2869 extern int readlink_copy(char __user *, int, const char *);
2870 extern int page_readlink(struct dentry *, char __user *, int);
2871 extern const char *page_get_link(struct dentry *, struct inode *,
2872 struct delayed_call *);
2873 extern void page_put_link(void *);
2874 extern int __page_symlink(struct inode *inode, const char *symname, int len,
2876 extern int page_symlink(struct inode *inode, const char *symname, int len);
2877 extern const struct inode_operations page_symlink_inode_operations;
2878 extern void kfree_link(void *);
2879 extern int generic_readlink(struct dentry *, char __user *, int);
2880 extern void generic_fillattr(struct inode *, struct kstat *);
2881 int vfs_getattr_nosec(struct path *path, struct kstat *stat);
2882 extern int vfs_getattr(struct path *, struct kstat *);
2883 void __inode_add_bytes(struct inode *inode, loff_t bytes);
2884 void inode_add_bytes(struct inode *inode, loff_t bytes);
2885 void __inode_sub_bytes(struct inode *inode, loff_t bytes);
2886 void inode_sub_bytes(struct inode *inode, loff_t bytes);
2887 loff_t inode_get_bytes(struct inode *inode);
2888 void inode_set_bytes(struct inode *inode, loff_t bytes);
2889 const char *simple_get_link(struct dentry *, struct inode *,
2890 struct delayed_call *);
2891 extern const struct inode_operations simple_symlink_inode_operations;
2893 extern int iterate_dir(struct file *, struct dir_context *);
2895 extern int vfs_stat(const char __user *, struct kstat *);
2896 extern int vfs_lstat(const char __user *, struct kstat *);
2897 extern int vfs_fstat(unsigned int, struct kstat *);
2898 extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
2900 extern int __generic_block_fiemap(struct inode *inode,
2901 struct fiemap_extent_info *fieinfo,
2902 loff_t start, loff_t len,
2903 get_block_t *get_block);
2904 extern int generic_block_fiemap(struct inode *inode,
2905 struct fiemap_extent_info *fieinfo, u64 start,
2906 u64 len, get_block_t *get_block);
2908 extern void get_filesystem(struct file_system_type *fs);
2909 extern void put_filesystem(struct file_system_type *fs);
2910 extern struct file_system_type *get_fs_type(const char *name);
2911 extern struct super_block *get_super(struct block_device *);
2912 extern struct super_block *get_super_thawed(struct block_device *);
2913 extern struct super_block *get_active_super(struct block_device *bdev);
2914 extern void drop_super(struct super_block *sb);
2915 extern void iterate_supers(void (*)(struct super_block *, void *), void *);
2916 extern void iterate_supers_type(struct file_system_type *,
2917 void (*)(struct super_block *, void *), void *);
2919 extern int dcache_dir_open(struct inode *, struct file *);
2920 extern int dcache_dir_close(struct inode *, struct file *);
2921 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2922 extern int dcache_readdir(struct file *, struct dir_context *);
2923 extern int simple_setattr(struct dentry *, struct iattr *);
2924 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
2925 extern int simple_statfs(struct dentry *, struct kstatfs *);
2926 extern int simple_open(struct inode *inode, struct file *file);
2927 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
2928 extern int simple_unlink(struct inode *, struct dentry *);
2929 extern int simple_rmdir(struct inode *, struct dentry *);
2930 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
2931 extern int noop_fsync(struct file *, loff_t, loff_t, int);
2932 extern int simple_empty(struct dentry *);
2933 extern int simple_readpage(struct file *file, struct page *page);
2934 extern int simple_write_begin(struct file *file, struct address_space *mapping,
2935 loff_t pos, unsigned len, unsigned flags,
2936 struct page **pagep, void **fsdata);
2937 extern int simple_write_end(struct file *file, struct address_space *mapping,
2938 loff_t pos, unsigned len, unsigned copied,
2939 struct page *page, void *fsdata);
2940 extern int always_delete_dentry(const struct dentry *);
2941 extern struct inode *alloc_anon_inode(struct super_block *);
2942 extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
2943 extern const struct dentry_operations simple_dentry_operations;
2945 extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
2946 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2947 extern const struct file_operations simple_dir_operations;
2948 extern const struct inode_operations simple_dir_inode_operations;
2949 extern void make_empty_dir_inode(struct inode *inode);
2950 extern bool is_empty_dir_inode(struct inode *inode);
2951 struct tree_descr { char *name; const struct file_operations *ops; int mode; };
2952 struct dentry *d_alloc_name(struct dentry *, const char *);
2953 extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
2954 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2955 extern void simple_release_fs(struct vfsmount **mount, int *count);
2957 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2958 loff_t *ppos, const void *from, size_t available);
2959 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
2960 const void __user *from, size_t count);
2962 extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
2963 extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
2965 extern int generic_check_addressable(unsigned, u64);
2967 #ifdef CONFIG_MIGRATION
2968 extern int buffer_migrate_page(struct address_space *,
2969 struct page *, struct page *,
2972 #define buffer_migrate_page NULL
2975 extern int inode_change_ok(const struct inode *, struct iattr *);
2976 extern int inode_newsize_ok(const struct inode *, loff_t offset);
2977 extern void setattr_copy(struct inode *inode, const struct iattr *attr);
2979 extern int file_update_time(struct file *file);
2981 extern int generic_show_options(struct seq_file *m, struct dentry *root);
2982 extern void save_mount_options(struct super_block *sb, char *options);
2983 extern void replace_mount_options(struct super_block *sb, char *options);
2985 static inline bool io_is_direct(struct file *filp)
2987 return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);
2990 static inline int iocb_flags(struct file *file)
2993 if (file->f_flags & O_APPEND)
2995 if (io_is_direct(file))
2997 if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
2999 if (file->f_flags & __O_SYNC)
3004 static inline ino_t parent_ino(struct dentry *dentry)
3009 * Don't strictly need d_lock here? If the parent ino could change
3010 * then surely we'd have a deeper race in the caller?
3012 spin_lock(&dentry->d_lock);
3013 res = dentry->d_parent->d_inode->i_ino;
3014 spin_unlock(&dentry->d_lock);
3018 /* Transaction based IO helpers */
3021 * An argresp is stored in an allocated page and holds the
3022 * size of the argument or response, along with its content
3024 struct simple_transaction_argresp {
3029 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
3031 char *simple_transaction_get(struct file *file, const char __user *buf,
3033 ssize_t simple_transaction_read(struct file *file, char __user *buf,
3034 size_t size, loff_t *pos);
3035 int simple_transaction_release(struct inode *inode, struct file *file);
3037 void simple_transaction_set(struct file *file, size_t n);
3040 * simple attribute files
3042 * These attributes behave similar to those in sysfs:
3044 * Writing to an attribute immediately sets a value, an open file can be
3045 * written to multiple times.
3047 * Reading from an attribute creates a buffer from the value that might get
3048 * read with multiple read calls. When the attribute has been read
3049 * completely, no further read calls are possible until the file is opened
3052 * All attributes contain a text representation of a numeric value
3053 * that are accessed with the get() and set() functions.
3055 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
3056 static int __fops ## _open(struct inode *inode, struct file *file) \
3058 __simple_attr_check_format(__fmt, 0ull); \
3059 return simple_attr_open(inode, file, __get, __set, __fmt); \
3061 static const struct file_operations __fops = { \
3062 .owner = THIS_MODULE, \
3063 .open = __fops ## _open, \
3064 .release = simple_attr_release, \
3065 .read = simple_attr_read, \
3066 .write = simple_attr_write, \
3067 .llseek = generic_file_llseek, \
3070 static inline __printf(1, 2)
3071 void __simple_attr_check_format(const char *fmt, ...)
3073 /* don't do anything, just let the compiler check the arguments; */
3076 int simple_attr_open(struct inode *inode, struct file *file,
3077 int (*get)(void *, u64 *), int (*set)(void *, u64),
3079 int simple_attr_release(struct inode *inode, struct file *file);
3080 ssize_t simple_attr_read(struct file *file, char __user *buf,
3081 size_t len, loff_t *ppos);
3082 ssize_t simple_attr_write(struct file *file, const char __user *buf,
3083 size_t len, loff_t *ppos);
3086 int proc_nr_files(struct ctl_table *table, int write,
3087 void __user *buffer, size_t *lenp, loff_t *ppos);
3088 int proc_nr_dentry(struct ctl_table *table, int write,
3089 void __user *buffer, size_t *lenp, loff_t *ppos);
3090 int proc_nr_inodes(struct ctl_table *table, int write,
3091 void __user *buffer, size_t *lenp, loff_t *ppos);
3092 int __init get_filesystem_list(char *buf);
3094 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
3095 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
3097 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
3098 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
3099 (flag & __FMODE_NONOTIFY)))
3101 static inline bool is_sxid(umode_t mode)
3103 return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
3106 static inline int check_sticky(struct inode *dir, struct inode *inode)
3108 if (!(dir->i_mode & S_ISVTX))
3111 return __check_sticky(dir, inode);
3114 static inline void inode_has_no_xattr(struct inode *inode)
3116 if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC))
3117 inode->i_flags |= S_NOSEC;
3120 static inline bool is_root_inode(struct inode *inode)
3122 return inode == inode->i_sb->s_root->d_inode;
3125 static inline bool dir_emit(struct dir_context *ctx,
3126 const char *name, int namelen,
3127 u64 ino, unsigned type)
3129 return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
3131 static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
3133 return ctx->actor(ctx, ".", 1, ctx->pos,
3134 file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
3136 static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
3138 return ctx->actor(ctx, "..", 2, ctx->pos,
3139 parent_ino(file->f_path.dentry), DT_DIR) == 0;
3141 static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
3143 if (ctx->pos == 0) {
3144 if (!dir_emit_dot(file, ctx))
3148 if (ctx->pos == 1) {
3149 if (!dir_emit_dotdot(file, ctx))
3155 static inline bool dir_relax(struct inode *inode)
3157 inode_unlock(inode);
3159 return !IS_DEADDIR(inode);
3162 static inline bool dir_relax_shared(struct inode *inode)
3164 inode_unlock_shared(inode);
3165 inode_lock_shared(inode);
3166 return !IS_DEADDIR(inode);
3169 extern bool path_noexec(const struct path *path);
3170 extern void inode_nohighmem(struct inode *inode);
3172 #endif /* _LINUX_FS_H */