5 #include <linux/linkage.h>
6 #include <linux/wait.h>
7 #include <linux/kdev_t.h>
8 #include <linux/dcache.h>
9 #include <linux/path.h>
10 #include <linux/stat.h>
11 #include <linux/cache.h>
12 #include <linux/list.h>
13 #include <linux/list_lru.h>
14 #include <linux/llist.h>
15 #include <linux/radix-tree.h>
16 #include <linux/rbtree.h>
17 #include <linux/init.h>
18 #include <linux/pid.h>
19 #include <linux/bug.h>
20 #include <linux/mutex.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>
33 #include <asm/byteorder.h>
34 #include <uapi/linux/fs.h>
36 struct export_operations;
42 struct pipe_inode_info;
43 struct poll_table_struct;
45 struct vm_area_struct;
48 struct swap_info_struct;
50 struct workqueue_struct;
53 extern void __init inode_init(void);
54 extern void __init inode_init_early(void);
55 extern void __init files_init(unsigned long);
57 extern struct files_stat_struct files_stat;
58 extern unsigned long get_max_files(void);
59 extern int sysctl_nr_open;
60 extern struct inodes_stat_t inodes_stat;
61 extern int leases_enable, lease_break_time;
62 extern int sysctl_protected_symlinks;
63 extern int sysctl_protected_hardlinks;
66 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
67 struct buffer_head *bh_result, int create);
68 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
69 ssize_t bytes, void *private);
71 #define MAY_EXEC 0x00000001
72 #define MAY_WRITE 0x00000002
73 #define MAY_READ 0x00000004
74 #define MAY_APPEND 0x00000008
75 #define MAY_ACCESS 0x00000010
76 #define MAY_OPEN 0x00000020
77 #define MAY_CHDIR 0x00000040
78 /* called from RCU mode, don't block */
79 #define MAY_NOT_BLOCK 0x00000080
82 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
83 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
86 /* file is open for reading */
87 #define FMODE_READ ((__force fmode_t)0x1)
88 /* file is open for writing */
89 #define FMODE_WRITE ((__force fmode_t)0x2)
90 /* file is seekable */
91 #define FMODE_LSEEK ((__force fmode_t)0x4)
92 /* file can be accessed using pread */
93 #define FMODE_PREAD ((__force fmode_t)0x8)
94 /* file can be accessed using pwrite */
95 #define FMODE_PWRITE ((__force fmode_t)0x10)
96 /* File is opened for execution with sys_execve / sys_uselib */
97 #define FMODE_EXEC ((__force fmode_t)0x20)
98 /* File is opened with O_NDELAY (only set for block devices) */
99 #define FMODE_NDELAY ((__force fmode_t)0x40)
100 /* File is opened with O_EXCL (only set for block devices) */
101 #define FMODE_EXCL ((__force fmode_t)0x80)
102 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
103 (specialy hack for floppy.c) */
104 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
105 /* 32bit hashes as llseek() offset (for directories) */
106 #define FMODE_32BITHASH ((__force fmode_t)0x200)
107 /* 64bit hashes as llseek() offset (for directories) */
108 #define FMODE_64BITHASH ((__force fmode_t)0x400)
111 * Don't update ctime and mtime.
113 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
114 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
116 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
118 /* Expect random access pattern */
119 #define FMODE_RANDOM ((__force fmode_t)0x1000)
121 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
122 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
124 /* File is opened with O_PATH; almost nothing can be done with it */
125 #define FMODE_PATH ((__force fmode_t)0x4000)
127 /* File needs atomic accesses to f_pos */
128 #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
129 /* Write access to underlying fs */
130 #define FMODE_WRITER ((__force fmode_t)0x10000)
131 /* Has read method(s) */
132 #define FMODE_CAN_READ ((__force fmode_t)0x20000)
133 /* Has write method(s) */
134 #define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
136 /* File was opened by fanotify and shouldn't generate fanotify events */
137 #define FMODE_NONOTIFY ((__force fmode_t)0x1000000)
140 * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
141 * that indicates that they should check the contents of the iovec are
142 * valid, but not check the memory that the iovec elements
145 #define CHECK_IOVEC_ONLY -1
148 * The below are the various read and write types that we support. Some of
149 * them include behavioral modifiers that send information down to the
150 * block layer and IO scheduler. Terminology:
152 * The block layer uses device plugging to defer IO a little bit, in
153 * the hope that we will see more IO very shortly. This increases
154 * coalescing of adjacent IO and thus reduces the number of IOs we
155 * have to send to the device. It also allows for better queuing,
156 * if the IO isn't mergeable. If the caller is going to be waiting
157 * for the IO, then he must ensure that the device is unplugged so
158 * that the IO is dispatched to the driver.
160 * All IO is handled async in Linux. This is fine for background
161 * writes, but for reads or writes that someone waits for completion
162 * on, we want to notify the block layer and IO scheduler so that they
163 * know about it. That allows them to make better scheduling
164 * decisions. So when the below references 'sync' and 'async', it
165 * is referencing this priority hint.
167 * With that in mind, the available types are:
169 * READ A normal read operation. Device will be plugged.
170 * READ_SYNC A synchronous read. Device is not plugged, caller can
171 * immediately wait on this read without caring about
173 * READA Used for read-ahead operations. Lower priority, and the
174 * block layer could (in theory) choose to ignore this
175 * request if it runs into resource problems.
176 * WRITE A normal async write. Device will be plugged.
177 * WRITE_SYNC Synchronous write. Identical to WRITE, but passes down
178 * the hint that someone will be waiting on this IO
179 * shortly. The write equivalent of READ_SYNC.
180 * WRITE_ODIRECT Special case write for O_DIRECT only.
181 * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush.
182 * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on
183 * non-volatile media on completion.
184 * WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded
185 * by a cache flush and data is guaranteed to be on
186 * non-volatile media on completion.
189 #define RW_MASK REQ_WRITE
190 #define RWA_MASK REQ_RAHEAD
193 #define WRITE RW_MASK
194 #define READA RWA_MASK
196 #define READ_SYNC (READ | REQ_SYNC)
197 #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE)
198 #define WRITE_ODIRECT (WRITE | REQ_SYNC)
199 #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH)
200 #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
201 #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
204 * Attribute flags. These should be or-ed together to figure out what
207 #define ATTR_MODE (1 << 0)
208 #define ATTR_UID (1 << 1)
209 #define ATTR_GID (1 << 2)
210 #define ATTR_SIZE (1 << 3)
211 #define ATTR_ATIME (1 << 4)
212 #define ATTR_MTIME (1 << 5)
213 #define ATTR_CTIME (1 << 6)
214 #define ATTR_ATIME_SET (1 << 7)
215 #define ATTR_MTIME_SET (1 << 8)
216 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
217 #define ATTR_ATTR_FLAG (1 << 10)
218 #define ATTR_KILL_SUID (1 << 11)
219 #define ATTR_KILL_SGID (1 << 12)
220 #define ATTR_FILE (1 << 13)
221 #define ATTR_KILL_PRIV (1 << 14)
222 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
223 #define ATTR_TIMES_SET (1 << 16)
226 * Whiteout is represented by a char device. The following constants define the
227 * mode and device number to use.
229 #define WHITEOUT_MODE 0
230 #define WHITEOUT_DEV 0
233 * This is the Inode Attributes structure, used for notify_change(). It
234 * uses the above definitions as flags, to know which values have changed.
235 * Also, in this manner, a Filesystem can look at only the values it cares
236 * about. Basically, these are the attributes that the VFS layer can
237 * request to change from the FS layer.
239 * Derek Atkins <warlord@MIT.EDU> 94-10-20
242 unsigned int ia_valid;
247 struct timespec ia_atime;
248 struct timespec ia_mtime;
249 struct timespec ia_ctime;
252 * Not an attribute, but an auxiliary info for filesystems wanting to
253 * implement an ftruncate() like method. NOTE: filesystem should
254 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
256 struct file *ia_file;
260 * Includes for diskquotas.
262 #include <linux/quota.h>
265 * Maximum number of layers of fs stack. Needs to be limited to
266 * prevent kernel stack overflow
268 #define FILESYSTEM_MAX_STACK_DEPTH 2
271 * enum positive_aop_returns - aop return codes with specific semantics
273 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
274 * completed, that the page is still locked, and
275 * should be considered active. The VM uses this hint
276 * to return the page to the active list -- it won't
277 * be a candidate for writeback again in the near
278 * future. Other callers must be careful to unlock
279 * the page if they get this return. Returned by
282 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
283 * unlocked it and the page might have been truncated.
284 * The caller should back up to acquiring a new page and
285 * trying again. The aop will be taking reasonable
286 * precautions not to livelock. If the caller held a page
287 * reference, it should drop it before retrying. Returned
290 * address_space_operation functions return these large constants to indicate
291 * special semantics to the caller. These are much larger than the bytes in a
292 * page to allow for functions that return the number of bytes operated on in a
296 enum positive_aop_returns {
297 AOP_WRITEPAGE_ACTIVATE = 0x80000,
298 AOP_TRUNCATED_PAGE = 0x80001,
301 #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
302 #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
303 #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct
304 * helper code (eg buffer layer)
305 * to clear GFP_FS from alloc */
308 * oh the beauties of C type declarations.
311 struct address_space;
312 struct writeback_control;
315 * "descriptor" for what we're up to with a read.
316 * This allows us to use the same read code yet
317 * have multiple different users of the data that
318 * we read from a file.
320 * The simplest case just copies the data to user
333 typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
334 unsigned long, unsigned long);
336 struct address_space_operations {
337 int (*writepage)(struct page *page, struct writeback_control *wbc);
338 int (*readpage)(struct file *, struct page *);
340 /* Write back some dirty pages from this mapping. */
341 int (*writepages)(struct address_space *, struct writeback_control *);
343 /* Set a page dirty. Return true if this dirtied it */
344 int (*set_page_dirty)(struct page *page);
346 int (*readpages)(struct file *filp, struct address_space *mapping,
347 struct list_head *pages, unsigned nr_pages);
349 int (*write_begin)(struct file *, struct address_space *mapping,
350 loff_t pos, unsigned len, unsigned flags,
351 struct page **pagep, void **fsdata);
352 int (*write_end)(struct file *, struct address_space *mapping,
353 loff_t pos, unsigned len, unsigned copied,
354 struct page *page, void *fsdata);
356 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
357 sector_t (*bmap)(struct address_space *, sector_t);
358 void (*invalidatepage) (struct page *, unsigned int, unsigned int);
359 int (*releasepage) (struct page *, gfp_t);
360 void (*freepage)(struct page *);
361 ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
362 int (*get_xip_mem)(struct address_space *, pgoff_t, int,
363 void **, unsigned long *);
365 * migrate the contents of a page to the specified target. If
366 * migrate_mode is MIGRATE_ASYNC, it must not block.
368 int (*migratepage) (struct address_space *,
369 struct page *, struct page *, enum migrate_mode);
370 int (*launder_page) (struct page *);
371 int (*is_partially_uptodate) (struct page *, unsigned long,
373 void (*is_dirty_writeback) (struct page *, bool *, bool *);
374 int (*error_remove_page)(struct address_space *, struct page *);
376 /* swapfile support */
377 int (*swap_activate)(struct swap_info_struct *sis, struct file *file,
379 void (*swap_deactivate)(struct file *file);
382 extern const struct address_space_operations empty_aops;
385 * pagecache_write_begin/pagecache_write_end must be used by general code
386 * to write into the pagecache.
388 int pagecache_write_begin(struct file *, struct address_space *mapping,
389 loff_t pos, unsigned len, unsigned flags,
390 struct page **pagep, void **fsdata);
392 int pagecache_write_end(struct file *, struct address_space *mapping,
393 loff_t pos, unsigned len, unsigned copied,
394 struct page *page, void *fsdata);
396 struct backing_dev_info;
397 struct address_space {
398 struct inode *host; /* owner: inode, block_device */
399 struct radix_tree_root page_tree; /* radix tree of all pages */
400 spinlock_t tree_lock; /* and lock protecting it */
401 atomic_t i_mmap_writable;/* count VM_SHARED mappings */
402 struct rb_root i_mmap; /* tree of private and shared mappings */
403 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
404 struct mutex i_mmap_mutex; /* protect tree, count, list */
405 /* Protected by tree_lock together with the radix tree */
406 unsigned long nrpages; /* number of total pages */
407 unsigned long nrshadows; /* number of shadow entries */
408 pgoff_t writeback_index;/* writeback starts here */
409 const struct address_space_operations *a_ops; /* methods */
410 unsigned long flags; /* error bits/gfp mask */
411 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
412 spinlock_t private_lock; /* for use by the address_space */
413 struct list_head private_list; /* ditto */
414 void *private_data; /* ditto */
415 } __attribute__((aligned(sizeof(long))));
417 * On most architectures that alignment is already the case; but
418 * must be enforced here for CRIS, to let the least significant bit
419 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
421 struct request_queue;
423 struct block_device {
424 dev_t bd_dev; /* not a kdev_t - it's a search key */
426 struct inode * bd_inode; /* will die */
427 struct super_block * bd_super;
428 struct mutex bd_mutex; /* open/close mutex */
429 struct list_head bd_inodes;
433 bool bd_write_holder;
435 struct list_head bd_holder_disks;
437 struct block_device * bd_contains;
438 unsigned bd_block_size;
439 struct hd_struct * bd_part;
440 /* number of times partitions within this device have been opened. */
441 unsigned bd_part_count;
443 struct gendisk * bd_disk;
444 struct request_queue * bd_queue;
445 struct list_head bd_list;
447 * Private data. You must have bd_claim'ed the block_device
448 * to use this. NOTE: bd_claim allows an owner to claim
449 * the same device multiple times, the owner must take special
450 * care to not mess up bd_private for that case.
452 unsigned long bd_private;
454 /* The counter of freeze processes */
455 int bd_fsfreeze_count;
456 /* Mutex for freeze */
457 struct mutex bd_fsfreeze_mutex;
461 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
464 #define PAGECACHE_TAG_DIRTY 0
465 #define PAGECACHE_TAG_WRITEBACK 1
466 #define PAGECACHE_TAG_TOWRITE 2
468 int mapping_tagged(struct address_space *mapping, int tag);
471 * Might pages of this file be mapped into userspace?
473 static inline int mapping_mapped(struct address_space *mapping)
475 return !RB_EMPTY_ROOT(&mapping->i_mmap) ||
476 !list_empty(&mapping->i_mmap_nonlinear);
480 * Might pages of this file have been modified in userspace?
481 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
482 * marks vma as VM_SHARED if it is shared, and the file was opened for
483 * writing i.e. vma may be mprotected writable even if now readonly.
485 * If i_mmap_writable is negative, no new writable mappings are allowed. You
486 * can only deny writable mappings, if none exists right now.
488 static inline int mapping_writably_mapped(struct address_space *mapping)
490 return atomic_read(&mapping->i_mmap_writable) > 0;
493 static inline int mapping_map_writable(struct address_space *mapping)
495 return atomic_inc_unless_negative(&mapping->i_mmap_writable) ?
499 static inline void mapping_unmap_writable(struct address_space *mapping)
501 atomic_dec(&mapping->i_mmap_writable);
504 static inline int mapping_deny_writable(struct address_space *mapping)
506 return atomic_dec_unless_positive(&mapping->i_mmap_writable) ?
510 static inline void mapping_allow_writable(struct address_space *mapping)
512 atomic_inc(&mapping->i_mmap_writable);
516 * Use sequence counter to get consistent i_size on 32-bit processors.
518 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
519 #include <linux/seqlock.h>
520 #define __NEED_I_SIZE_ORDERED
521 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
523 #define i_size_ordered_init(inode) do { } while (0)
527 #define ACL_NOT_CACHED ((void *)(-1))
529 #define IOP_FASTPERM 0x0001
530 #define IOP_LOOKUP 0x0002
531 #define IOP_NOFOLLOW 0x0004
534 * Keep mostly read-only and often accessed (especially for
535 * the RCU path lookup and 'stat' data) fields at the beginning
536 * of the 'struct inode'
540 unsigned short i_opflags;
543 unsigned int i_flags;
545 #ifdef CONFIG_FS_POSIX_ACL
546 struct posix_acl *i_acl;
547 struct posix_acl *i_default_acl;
550 const struct inode_operations *i_op;
551 struct super_block *i_sb;
552 struct address_space *i_mapping;
554 #ifdef CONFIG_SECURITY
558 /* Stat data, not accessed from path walking */
561 * Filesystems may only read i_nlink directly. They shall use the
562 * following functions for modification:
564 * (set|clear|inc|drop)_nlink
565 * inode_(inc|dec)_link_count
568 const unsigned int i_nlink;
569 unsigned int __i_nlink;
573 struct timespec i_atime;
574 struct timespec i_mtime;
575 struct timespec i_ctime;
576 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
577 unsigned short i_bytes;
578 unsigned int i_blkbits;
581 #ifdef __NEED_I_SIZE_ORDERED
582 seqcount_t i_size_seqcount;
586 unsigned long i_state;
587 struct mutex i_mutex;
589 unsigned long dirtied_when; /* jiffies of first dirtying */
591 struct hlist_node i_hash;
592 struct list_head i_wb_list; /* backing dev IO list */
593 struct list_head i_lru; /* inode LRU list */
594 struct list_head i_sb_list;
596 struct hlist_head i_dentry;
597 struct rcu_head i_rcu;
601 atomic_t i_dio_count;
602 atomic_t i_writecount;
604 atomic_t i_readcount; /* struct files open RO */
606 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
607 struct file_lock *i_flock;
608 struct address_space i_data;
610 struct dquot *i_dquot[MAXQUOTAS];
612 struct list_head i_devices;
614 struct pipe_inode_info *i_pipe;
615 struct block_device *i_bdev;
621 #ifdef CONFIG_FSNOTIFY
622 __u32 i_fsnotify_mask; /* all events this inode cares about */
623 struct hlist_head i_fsnotify_marks;
626 void *i_private; /* fs or device private pointer */
629 static inline int inode_unhashed(struct inode *inode)
631 return hlist_unhashed(&inode->i_hash);
635 * inode->i_mutex nesting subclasses for the lock validator:
637 * 0: the object of the current VFS operation
641 * 4: second non-directory
642 * 5: second parent (when locking independent directories in rename)
644 * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
645 * non-directories at once.
647 * The locking order between these classes is
648 * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
650 enum inode_i_mutex_lock_class
660 void lock_two_nondirectories(struct inode *, struct inode*);
661 void unlock_two_nondirectories(struct inode *, struct inode*);
664 * NOTE: in a 32bit arch with a preemptable kernel and
665 * an UP compile the i_size_read/write must be atomic
666 * with respect to the local cpu (unlike with preempt disabled),
667 * but they don't need to be atomic with respect to other cpus like in
668 * true SMP (so they need either to either locally disable irq around
669 * the read or for example on x86 they can be still implemented as a
670 * cmpxchg8b without the need of the lock prefix). For SMP compiles
671 * and 64bit archs it makes no difference if preempt is enabled or not.
673 static inline loff_t i_size_read(const struct inode *inode)
675 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
680 seq = read_seqcount_begin(&inode->i_size_seqcount);
681 i_size = inode->i_size;
682 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
684 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
688 i_size = inode->i_size;
692 return inode->i_size;
697 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
698 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
699 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
701 static inline void i_size_write(struct inode *inode, loff_t i_size)
703 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
705 write_seqcount_begin(&inode->i_size_seqcount);
706 inode->i_size = i_size;
707 write_seqcount_end(&inode->i_size_seqcount);
709 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
711 inode->i_size = i_size;
714 inode->i_size = i_size;
718 /* Helper functions so that in most cases filesystems will
719 * not need to deal directly with kuid_t and kgid_t and can
720 * instead deal with the raw numeric values that are stored
723 static inline uid_t i_uid_read(const struct inode *inode)
725 return from_kuid(&init_user_ns, inode->i_uid);
728 static inline gid_t i_gid_read(const struct inode *inode)
730 return from_kgid(&init_user_ns, inode->i_gid);
733 static inline void i_uid_write(struct inode *inode, uid_t uid)
735 inode->i_uid = make_kuid(&init_user_ns, uid);
738 static inline void i_gid_write(struct inode *inode, gid_t gid)
740 inode->i_gid = make_kgid(&init_user_ns, gid);
743 static inline unsigned iminor(const struct inode *inode)
745 return MINOR(inode->i_rdev);
748 static inline unsigned imajor(const struct inode *inode)
750 return MAJOR(inode->i_rdev);
753 extern struct block_device *I_BDEV(struct inode *inode);
756 rwlock_t lock; /* protects pid, uid, euid fields */
757 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
758 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
759 kuid_t uid, euid; /* uid/euid of process setting the owner */
760 int signum; /* posix.1b rt signal to be delivered on IO */
764 * Track a single file's readahead state
766 struct file_ra_state {
767 pgoff_t start; /* where readahead started */
768 unsigned int size; /* # of readahead pages */
769 unsigned int async_size; /* do asynchronous readahead when
770 there are only # of pages ahead */
772 unsigned int ra_pages; /* Maximum readahead window */
773 unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
774 loff_t prev_pos; /* Cache last read() position */
778 * Check if @index falls in the readahead windows.
780 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
782 return (index >= ra->start &&
783 index < ra->start + ra->size);
788 struct llist_node fu_llist;
789 struct rcu_head fu_rcuhead;
792 #define f_dentry f_path.dentry
793 struct inode *f_inode; /* cached value */
794 const struct file_operations *f_op;
797 * Protects f_ep_links, f_flags.
798 * Must not be taken from IRQ context.
801 atomic_long_t f_count;
802 unsigned int f_flags;
804 struct mutex f_pos_lock;
806 struct fown_struct f_owner;
807 const struct cred *f_cred;
808 struct file_ra_state f_ra;
811 #ifdef CONFIG_SECURITY
814 /* needed for tty driver, and maybe others */
818 /* Used by fs/eventpoll.c to link all the hooks to this file */
819 struct list_head f_ep_links;
820 struct list_head f_tfile_llink;
821 #endif /* #ifdef CONFIG_EPOLL */
822 struct address_space *f_mapping;
823 } __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */
828 /* file identifier */
829 unsigned char f_handle[0];
832 static inline struct file *get_file(struct file *f)
834 atomic_long_inc(&f->f_count);
837 #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
838 #define file_count(x) atomic_long_read(&(x)->f_count)
840 #define MAX_NON_LFS ((1UL<<31) - 1)
842 /* Page cache limit. The filesystems should put that into their s_maxbytes
843 limits, otherwise bad things can happen in VM. */
844 #if BITS_PER_LONG==32
845 #define MAX_LFS_FILESIZE (((loff_t)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
846 #elif BITS_PER_LONG==64
847 #define MAX_LFS_FILESIZE ((loff_t)0x7fffffffffffffffLL)
852 #define FL_DELEG 4 /* NFSv4 delegation */
853 #define FL_ACCESS 8 /* not trying to lock, just looking */
854 #define FL_EXISTS 16 /* when unlocking, test for existence */
855 #define FL_LEASE 32 /* lease held on this file */
856 #define FL_CLOSE 64 /* unlock on close */
857 #define FL_SLEEP 128 /* A blocking lock */
858 #define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */
859 #define FL_UNLOCK_PENDING 512 /* Lease is being broken */
860 #define FL_OFDLCK 1024 /* lock is "owned" by struct file */
863 * Special return value from posix_lock_file() and vfs_lock_file() for
864 * asynchronous locking.
866 #define FILE_LOCK_DEFERRED 1
868 /* legacy typedef, should eventually be removed */
869 typedef void *fl_owner_t;
871 struct file_lock_operations {
872 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
873 void (*fl_release_private)(struct file_lock *);
876 struct lock_manager_operations {
877 int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
878 unsigned long (*lm_owner_key)(struct file_lock *);
879 void (*lm_get_owner)(struct file_lock *, struct file_lock *);
880 void (*lm_put_owner)(struct file_lock *);
881 void (*lm_notify)(struct file_lock *); /* unblock callback */
882 int (*lm_grant)(struct file_lock *, int);
883 bool (*lm_break)(struct file_lock *);
884 int (*lm_change)(struct file_lock **, int, struct list_head *);
885 void (*lm_setup)(struct file_lock *, void **);
888 struct lock_manager {
889 struct list_head list;
893 void locks_start_grace(struct net *, struct lock_manager *);
894 void locks_end_grace(struct lock_manager *);
895 int locks_in_grace(struct net *);
897 /* that will die - we need it for nfs_lock_info */
898 #include <linux/nfs_fs_i.h>
901 * struct file_lock represents a generic "file lock". It's used to represent
902 * POSIX byte range locks, BSD (flock) locks, and leases. It's important to
903 * note that the same struct is used to represent both a request for a lock and
904 * the lock itself, but the same object is never used for both.
906 * FIXME: should we create a separate "struct lock_request" to help distinguish
909 * The i_flock list is ordered by:
911 * 1) lock type -- FL_LEASEs first, then FL_FLOCK, and finally FL_POSIX
913 * 3) lock range start
916 * Obviously, the last two criteria only matter for POSIX locks.
919 struct file_lock *fl_next; /* singly linked list for this inode */
920 struct hlist_node fl_link; /* node in global lists */
921 struct list_head fl_block; /* circular list of blocked processes */
923 unsigned int fl_flags;
924 unsigned char fl_type;
926 int fl_link_cpu; /* what cpu's list is this on? */
927 struct pid *fl_nspid;
928 wait_queue_head_t fl_wait;
929 struct file *fl_file;
933 struct fasync_struct * fl_fasync; /* for lease break notifications */
934 /* for lease breaks: */
935 unsigned long fl_break_time;
936 unsigned long fl_downgrade_time;
938 const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
939 const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
941 struct nfs_lock_info nfs_fl;
942 struct nfs4_lock_info nfs4_fl;
944 struct list_head link; /* link in AFS vnode's pending_locks list */
945 int state; /* state of grant or error if -ve */
950 /* The following constant reflects the upper bound of the file/locking space */
952 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
953 #define OFFSET_MAX INT_LIMIT(loff_t)
954 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
957 #include <linux/fcntl.h>
959 extern void send_sigio(struct fown_struct *fown, int fd, int band);
961 #ifdef CONFIG_FILE_LOCKING
962 extern int fcntl_getlk(struct file *, unsigned int, struct flock __user *);
963 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
964 struct flock __user *);
966 #if BITS_PER_LONG == 32
967 extern int fcntl_getlk64(struct file *, unsigned int, struct flock64 __user *);
968 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
969 struct flock64 __user *);
972 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
973 extern int fcntl_getlease(struct file *filp);
976 void locks_free_lock(struct file_lock *fl);
977 extern void locks_init_lock(struct file_lock *);
978 extern struct file_lock * locks_alloc_lock(void);
979 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
980 extern void locks_copy_conflock(struct file_lock *, struct file_lock *);
981 extern void locks_remove_posix(struct file *, fl_owner_t);
982 extern void locks_remove_file(struct file *);
983 extern void locks_release_private(struct file_lock *);
984 extern void posix_test_lock(struct file *, struct file_lock *);
985 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
986 extern int posix_lock_file_wait(struct file *, struct file_lock *);
987 extern int posix_unblock_lock(struct file_lock *);
988 extern int vfs_test_lock(struct file *, struct file_lock *);
989 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
990 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
991 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
992 extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
993 extern void lease_get_mtime(struct inode *, struct timespec *time);
994 extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
995 extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
996 extern int lease_modify(struct file_lock **, int, struct list_head *);
997 #else /* !CONFIG_FILE_LOCKING */
998 static inline int fcntl_getlk(struct file *file, unsigned int cmd,
999 struct flock __user *user)
1004 static inline int fcntl_setlk(unsigned int fd, struct file *file,
1005 unsigned int cmd, struct flock __user *user)
1010 #if BITS_PER_LONG == 32
1011 static inline int fcntl_getlk64(struct file *file, unsigned int cmd,
1012 struct flock64 __user *user)
1017 static inline int fcntl_setlk64(unsigned int fd, struct file *file,
1018 unsigned int cmd, struct flock64 __user *user)
1023 static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
1028 static inline int fcntl_getlease(struct file *filp)
1033 static inline void locks_init_lock(struct file_lock *fl)
1038 static inline void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
1043 static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1048 static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
1053 static inline void locks_remove_file(struct file *filp)
1058 static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
1063 static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
1064 struct file_lock *conflock)
1069 static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
1074 static inline int posix_unblock_lock(struct file_lock *waiter)
1079 static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
1084 static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
1085 struct file_lock *fl, struct file_lock *conf)
1090 static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
1095 static inline int flock_lock_file_wait(struct file *filp,
1096 struct file_lock *request)
1101 static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
1106 static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
1111 static inline int generic_setlease(struct file *filp, long arg,
1112 struct file_lock **flp, void **priv)
1117 static inline int vfs_setlease(struct file *filp, long arg,
1118 struct file_lock **lease, void **priv)
1123 static inline int lease_modify(struct file_lock **before, int arg,
1124 struct list_head *dispose)
1128 #endif /* !CONFIG_FILE_LOCKING */
1131 struct fasync_struct {
1135 struct fasync_struct *fa_next; /* singly linked list */
1136 struct file *fa_file;
1137 struct rcu_head fa_rcu;
1140 #define FASYNC_MAGIC 0x4601
1142 /* SMP safe fasync helpers: */
1143 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1144 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1145 extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1146 extern struct fasync_struct *fasync_alloc(void);
1147 extern void fasync_free(struct fasync_struct *);
1149 /* can be called from interrupts */
1150 extern void kill_fasync(struct fasync_struct **, int, int);
1152 extern void __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1153 extern void f_setown(struct file *filp, unsigned long arg, int force);
1154 extern void f_delown(struct file *filp);
1155 extern pid_t f_getown(struct file *filp);
1156 extern int send_sigurg(struct fown_struct *fown);
1164 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1165 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1166 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1167 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1168 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1170 extern struct list_head super_blocks;
1171 extern spinlock_t sb_lock;
1173 /* Possible states of 'frozen' field */
1175 SB_UNFROZEN = 0, /* FS is unfrozen */
1176 SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */
1177 SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */
1178 SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop
1179 * internal threads if needed) */
1180 SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */
1183 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
1186 /* Counters for counting writers at each level */
1187 struct percpu_counter counter[SB_FREEZE_LEVELS];
1188 wait_queue_head_t wait; /* queue for waiting for
1189 writers / faults to finish */
1190 int frozen; /* Is sb frozen? */
1191 wait_queue_head_t wait_unfrozen; /* queue for waiting for
1193 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1194 struct lockdep_map lock_map[SB_FREEZE_LEVELS];
1198 struct super_block {
1199 struct list_head s_list; /* Keep this first */
1200 dev_t s_dev; /* search index; _not_ kdev_t */
1201 unsigned char s_blocksize_bits;
1202 unsigned long s_blocksize;
1203 loff_t s_maxbytes; /* Max file size */
1204 struct file_system_type *s_type;
1205 const struct super_operations *s_op;
1206 const struct dquot_operations *dq_op;
1207 const struct quotactl_ops *s_qcop;
1208 const struct export_operations *s_export_op;
1209 unsigned long s_flags;
1210 unsigned long s_magic;
1211 struct dentry *s_root;
1212 struct rw_semaphore s_umount;
1215 #ifdef CONFIG_SECURITY
1218 const struct xattr_handler **s_xattr;
1220 struct list_head s_inodes; /* all inodes */
1221 struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
1222 struct list_head s_mounts; /* list of mounts; _not_ for fs use */
1223 struct block_device *s_bdev;
1224 struct backing_dev_info *s_bdi;
1225 struct mtd_info *s_mtd;
1226 struct hlist_node s_instances;
1227 unsigned int s_quota_types; /* Bitmask of supported quota types */
1228 struct quota_info s_dquot; /* Diskquota specific options */
1230 struct sb_writers s_writers;
1232 char s_id[32]; /* Informational name */
1233 u8 s_uuid[16]; /* UUID */
1235 void *s_fs_info; /* Filesystem private info */
1236 unsigned int s_max_links;
1239 /* Granularity of c/m/atime in ns.
1240 Cannot be worse than a second */
1244 * The next field is for VFS *only*. No filesystems have any business
1245 * even looking at it. You had been warned.
1247 struct mutex s_vfs_rename_mutex; /* Kludge */
1250 * Filesystem subtype. If non-empty the filesystem type field
1251 * in /proc/mounts will be "type.subtype"
1256 * Saved mount options for lazy filesystems using
1257 * generic_show_options()
1259 char __rcu *s_options;
1260 const struct dentry_operations *s_d_op; /* default d_op for dentries */
1263 * Saved pool identifier for cleancache (-1 means none)
1265 int cleancache_poolid;
1267 struct shrinker s_shrink; /* per-sb shrinker handle */
1269 /* Number of inodes with nlink == 0 but still referenced */
1270 atomic_long_t s_remove_count;
1272 /* Being remounted read-only */
1273 int s_readonly_remount;
1275 /* AIO completions deferred from interrupt context */
1276 struct workqueue_struct *s_dio_done_wq;
1277 struct hlist_head s_pins;
1280 * Keep the lru lists last in the structure so they always sit on their
1281 * own individual cachelines.
1283 struct list_lru s_dentry_lru ____cacheline_aligned_in_smp;
1284 struct list_lru s_inode_lru ____cacheline_aligned_in_smp;
1285 struct rcu_head rcu;
1288 * Indicates how deep in a filesystem stack this SB is
1293 extern struct timespec current_fs_time(struct super_block *sb);
1296 * Snapshotting support.
1299 void __sb_end_write(struct super_block *sb, int level);
1300 int __sb_start_write(struct super_block *sb, int level, bool wait);
1303 * sb_end_write - drop write access to a superblock
1304 * @sb: the super we wrote to
1306 * Decrement number of writers to the filesystem. Wake up possible waiters
1307 * wanting to freeze the filesystem.
1309 static inline void sb_end_write(struct super_block *sb)
1311 __sb_end_write(sb, SB_FREEZE_WRITE);
1315 * sb_end_pagefault - drop write access to a superblock from a page fault
1316 * @sb: the super we wrote to
1318 * Decrement number of processes handling write page fault to the filesystem.
1319 * Wake up possible waiters wanting to freeze the filesystem.
1321 static inline void sb_end_pagefault(struct super_block *sb)
1323 __sb_end_write(sb, SB_FREEZE_PAGEFAULT);
1327 * sb_end_intwrite - drop write access to a superblock for internal fs purposes
1328 * @sb: the super we wrote to
1330 * Decrement fs-internal number of writers to the filesystem. Wake up possible
1331 * waiters wanting to freeze the filesystem.
1333 static inline void sb_end_intwrite(struct super_block *sb)
1335 __sb_end_write(sb, SB_FREEZE_FS);
1339 * sb_start_write - get write access to a superblock
1340 * @sb: the super we write to
1342 * When a process wants to write data or metadata to a file system (i.e. dirty
1343 * a page or an inode), it should embed the operation in a sb_start_write() -
1344 * sb_end_write() pair to get exclusion against file system freezing. This
1345 * function increments number of writers preventing freezing. If the file
1346 * system is already frozen, the function waits until the file system is
1349 * Since freeze protection behaves as a lock, users have to preserve
1350 * ordering of freeze protection and other filesystem locks. Generally,
1351 * freeze protection should be the outermost lock. In particular, we have:
1354 * -> i_mutex (write path, truncate, directory ops, ...)
1355 * -> s_umount (freeze_super, thaw_super)
1357 static inline void sb_start_write(struct super_block *sb)
1359 __sb_start_write(sb, SB_FREEZE_WRITE, true);
1362 static inline int sb_start_write_trylock(struct super_block *sb)
1364 return __sb_start_write(sb, SB_FREEZE_WRITE, false);
1368 * sb_start_pagefault - get write access to a superblock from a page fault
1369 * @sb: the super we write to
1371 * When a process starts handling write page fault, it should embed the
1372 * operation into sb_start_pagefault() - sb_end_pagefault() pair to get
1373 * exclusion against file system freezing. This is needed since the page fault
1374 * is going to dirty a page. This function increments number of running page
1375 * faults preventing freezing. If the file system is already frozen, the
1376 * function waits until the file system is thawed.
1378 * Since page fault freeze protection behaves as a lock, users have to preserve
1379 * ordering of freeze protection and other filesystem locks. It is advised to
1380 * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault
1381 * handling code implies lock dependency:
1384 * -> sb_start_pagefault
1386 static inline void sb_start_pagefault(struct super_block *sb)
1388 __sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
1392 * sb_start_intwrite - get write access to a superblock for internal fs purposes
1393 * @sb: the super we write to
1395 * This is the third level of protection against filesystem freezing. It is
1396 * free for use by a filesystem. The only requirement is that it must rank
1397 * below sb_start_pagefault.
1399 * For example filesystem can call sb_start_intwrite() when starting a
1400 * transaction which somewhat eases handling of freezing for internal sources
1401 * of filesystem changes (internal fs threads, discarding preallocation on file
1404 static inline void sb_start_intwrite(struct super_block *sb)
1406 __sb_start_write(sb, SB_FREEZE_FS, true);
1410 extern bool inode_owner_or_capable(const struct inode *inode);
1413 * VFS helper functions..
1415 extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
1416 extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
1417 extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
1418 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
1419 extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
1420 extern int vfs_rmdir(struct inode *, struct dentry *);
1421 extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
1422 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
1423 extern int vfs_whiteout(struct inode *, struct dentry *);
1426 * VFS dentry helper functions.
1428 extern void dentry_unhash(struct dentry *dentry);
1431 * VFS file helper functions.
1433 extern void inode_init_owner(struct inode *inode, const struct inode *dir,
1436 * VFS FS_IOC_FIEMAP helper definitions.
1438 struct fiemap_extent_info {
1439 unsigned int fi_flags; /* Flags as passed from user */
1440 unsigned int fi_extents_mapped; /* Number of mapped extents */
1441 unsigned int fi_extents_max; /* Size of fiemap_extent array */
1442 struct fiemap_extent __user *fi_extents_start; /* Start of
1443 fiemap_extent array */
1445 int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
1446 u64 phys, u64 len, u32 flags);
1447 int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
1452 * NOTE! These match bits 12..15 of stat.st_mode
1453 * (ie "(i_mode >> 12) & 15").
1455 #define DT_UNKNOWN 0
1466 * This is the "filldir" function type, used by readdir() to let
1467 * the kernel specify what kind of dirent layout it wants to have.
1468 * This allows the kernel to read directories into kernel space or
1469 * to have different dirent layouts depending on the binary type.
1471 typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
1472 struct dir_context {
1473 const filldir_t actor;
1477 struct block_device_operations;
1479 /* These macros are for out of kernel modules to test that
1480 * the kernel supports the unlocked_ioctl and compat_ioctl
1481 * fields in struct file_operations. */
1482 #define HAVE_COMPAT_IOCTL 1
1483 #define HAVE_UNLOCKED_IOCTL 1
1487 struct file_operations {
1488 struct module *owner;
1489 loff_t (*llseek) (struct file *, loff_t, int);
1490 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1491 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1492 ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1493 ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1494 ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
1495 ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
1496 int (*iterate) (struct file *, struct dir_context *);
1497 unsigned int (*poll) (struct file *, struct poll_table_struct *);
1498 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1499 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1500 int (*mmap) (struct file *, struct vm_area_struct *);
1501 int (*open) (struct inode *, struct file *);
1502 int (*flush) (struct file *, fl_owner_t id);
1503 int (*release) (struct inode *, struct file *);
1504 int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1505 int (*aio_fsync) (struct kiocb *, int datasync);
1506 int (*fasync) (int, struct file *, int);
1507 int (*lock) (struct file *, int, struct file_lock *);
1508 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1509 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1510 int (*check_flags)(int);
1511 int (*flock) (struct file *, int, struct file_lock *);
1512 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1513 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1514 int (*setlease)(struct file *, long, struct file_lock **, void **);
1515 long (*fallocate)(struct file *file, int mode, loff_t offset,
1517 int (*show_fdinfo)(struct seq_file *m, struct file *f);
1520 struct inode_operations {
1521 struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
1522 void * (*follow_link) (struct dentry *, struct nameidata *);
1523 int (*permission) (struct inode *, int);
1524 struct posix_acl * (*get_acl)(struct inode *, int);
1526 int (*readlink) (struct dentry *, char __user *,int);
1527 void (*put_link) (struct dentry *, struct nameidata *, void *);
1529 int (*create) (struct inode *,struct dentry *, umode_t, bool);
1530 int (*link) (struct dentry *,struct inode *,struct dentry *);
1531 int (*unlink) (struct inode *,struct dentry *);
1532 int (*symlink) (struct inode *,struct dentry *,const char *);
1533 int (*mkdir) (struct inode *,struct dentry *,umode_t);
1534 int (*rmdir) (struct inode *,struct dentry *);
1535 int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
1536 int (*rename) (struct inode *, struct dentry *,
1537 struct inode *, struct dentry *);
1538 int (*rename2) (struct inode *, struct dentry *,
1539 struct inode *, struct dentry *, unsigned int);
1540 int (*setattr) (struct dentry *, struct iattr *);
1541 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1542 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
1543 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1544 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1545 int (*removexattr) (struct dentry *, const char *);
1546 int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1548 int (*update_time)(struct inode *, struct timespec *, int);
1549 int (*atomic_open)(struct inode *, struct dentry *,
1550 struct file *, unsigned open_flag,
1551 umode_t create_mode, int *opened);
1552 int (*tmpfile) (struct inode *, struct dentry *, umode_t);
1553 int (*set_acl)(struct inode *, struct posix_acl *, int);
1555 /* WARNING: probably going away soon, do not use! */
1556 int (*dentry_open)(struct dentry *, struct file *, const struct cred *);
1557 } ____cacheline_aligned;
1559 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1560 unsigned long nr_segs, unsigned long fast_segs,
1561 struct iovec *fast_pointer,
1562 struct iovec **ret_pointer);
1564 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1565 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1566 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1567 unsigned long, loff_t *);
1568 extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1569 unsigned long, loff_t *);
1571 struct super_operations {
1572 struct inode *(*alloc_inode)(struct super_block *sb);
1573 void (*destroy_inode)(struct inode *);
1575 void (*dirty_inode) (struct inode *, int flags);
1576 int (*write_inode) (struct inode *, struct writeback_control *wbc);
1577 int (*drop_inode) (struct inode *);
1578 void (*evict_inode) (struct inode *);
1579 void (*put_super) (struct super_block *);
1580 int (*sync_fs)(struct super_block *sb, int wait);
1581 int (*freeze_fs) (struct super_block *);
1582 int (*unfreeze_fs) (struct super_block *);
1583 int (*statfs) (struct dentry *, struct kstatfs *);
1584 int (*remount_fs) (struct super_block *, int *, char *);
1585 void (*umount_begin) (struct super_block *);
1587 int (*show_options)(struct seq_file *, struct dentry *);
1588 int (*show_devname)(struct seq_file *, struct dentry *);
1589 int (*show_path)(struct seq_file *, struct dentry *);
1590 int (*show_stats)(struct seq_file *, struct dentry *);
1592 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1593 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1594 struct dquot **(*get_dquots)(struct inode *);
1596 int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
1597 long (*nr_cached_objects)(struct super_block *, int);
1598 long (*free_cached_objects)(struct super_block *, long, int);
1602 * Inode flags - they have no relation to superblock flags now
1604 #define S_SYNC 1 /* Writes are synced at once */
1605 #define S_NOATIME 2 /* Do not update access times */
1606 #define S_APPEND 4 /* Append-only file */
1607 #define S_IMMUTABLE 8 /* Immutable file */
1608 #define S_DEAD 16 /* removed, but still open directory */
1609 #define S_NOQUOTA 32 /* Inode is not counted to quota */
1610 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
1611 #define S_NOCMTIME 128 /* Do not update file c/mtime */
1612 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
1613 #define S_PRIVATE 512 /* Inode is fs-internal */
1614 #define S_IMA 1024 /* Inode has an associated IMA struct */
1615 #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
1616 #define S_NOSEC 4096 /* no suid or xattr security attributes */
1619 * Note that nosuid etc flags are inode-specific: setting some file-system
1620 * flags just means all the inodes inherit those flags by default. It might be
1621 * possible to override it selectively if you really wanted to with some
1622 * ioctl() that is not currently implemented.
1624 * Exception: MS_RDONLY is always applied to the entire file system.
1626 * Unfortunately, it is possible to change a filesystems flags with it mounted
1627 * with files in use. This means that all of the inodes will not have their
1628 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
1629 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
1631 #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg))
1633 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
1634 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
1635 ((inode)->i_flags & S_SYNC))
1636 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
1637 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
1638 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
1639 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
1640 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
1642 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
1643 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
1644 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
1645 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
1647 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
1648 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
1649 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
1650 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
1651 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
1652 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
1653 #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
1655 #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
1656 (inode)->i_rdev == WHITEOUT_DEV)
1659 * Inode state bits. Protected by inode->i_lock
1661 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
1662 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
1664 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
1665 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
1666 * various stages of removing an inode.
1668 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
1670 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
1671 * fdatasync(). i_atime is the usual cause.
1672 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
1673 * these changes separately from I_DIRTY_SYNC so that we
1674 * don't have to write inode on fdatasync() when only
1675 * mtime has changed in it.
1676 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
1677 * I_NEW Serves as both a mutex and completion notification.
1678 * New inodes set I_NEW. If two processes both create
1679 * the same inode, one of them will release its inode and
1680 * wait for I_NEW to be released before returning.
1681 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
1682 * also cause waiting on I_NEW, without I_NEW actually
1683 * being set. find_inode() uses this to prevent returning
1684 * nearly-dead inodes.
1685 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
1686 * is zero. I_FREEING must be set when I_WILL_FREE is
1688 * I_FREEING Set when inode is about to be freed but still has dirty
1689 * pages or buffers attached or the inode itself is still
1691 * I_CLEAR Added by clear_inode(). In this state the inode is
1692 * clean and can be destroyed. Inode keeps I_FREEING.
1694 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
1695 * prohibited for many purposes. iget() must wait for
1696 * the inode to be completely released, then create it
1697 * anew. Other functions will just ignore such inodes,
1698 * if appropriate. I_NEW is used for waiting.
1700 * I_SYNC Writeback of inode is running. The bit is set during
1701 * data writeback, and cleared with a wakeup on the bit
1702 * address once it is done. The bit is also used to pin
1703 * the inode in memory for flusher thread.
1705 * I_REFERENCED Marks the inode as recently references on the LRU list.
1707 * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit().
1709 * Q: What is the difference between I_WILL_FREE and I_FREEING?
1711 #define I_DIRTY_SYNC (1 << 0)
1712 #define I_DIRTY_DATASYNC (1 << 1)
1713 #define I_DIRTY_PAGES (1 << 2)
1715 #define I_NEW (1 << __I_NEW)
1716 #define I_WILL_FREE (1 << 4)
1717 #define I_FREEING (1 << 5)
1718 #define I_CLEAR (1 << 6)
1720 #define I_SYNC (1 << __I_SYNC)
1721 #define I_REFERENCED (1 << 8)
1722 #define __I_DIO_WAKEUP 9
1723 #define I_DIO_WAKEUP (1 << I_DIO_WAKEUP)
1724 #define I_LINKABLE (1 << 10)
1726 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1728 extern void __mark_inode_dirty(struct inode *, int);
1729 static inline void mark_inode_dirty(struct inode *inode)
1731 __mark_inode_dirty(inode, I_DIRTY);
1734 static inline void mark_inode_dirty_sync(struct inode *inode)
1736 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1739 extern void inc_nlink(struct inode *inode);
1740 extern void drop_nlink(struct inode *inode);
1741 extern void clear_nlink(struct inode *inode);
1742 extern void set_nlink(struct inode *inode, unsigned int nlink);
1744 static inline void inode_inc_link_count(struct inode *inode)
1747 mark_inode_dirty(inode);
1750 static inline void inode_dec_link_count(struct inode *inode)
1753 mark_inode_dirty(inode);
1757 * inode_inc_iversion - increments i_version
1758 * @inode: inode that need to be updated
1760 * Every time the inode is modified, the i_version field will be incremented.
1761 * The filesystem has to be mounted with i_version flag
1764 static inline void inode_inc_iversion(struct inode *inode)
1766 spin_lock(&inode->i_lock);
1768 spin_unlock(&inode->i_lock);
1771 enum file_time_flags {
1778 extern void touch_atime(const struct path *);
1779 static inline void file_accessed(struct file *file)
1781 if (!(file->f_flags & O_NOATIME))
1782 touch_atime(&file->f_path);
1785 int sync_inode(struct inode *inode, struct writeback_control *wbc);
1786 int sync_inode_metadata(struct inode *inode, int wait);
1788 struct file_system_type {
1791 #define FS_REQUIRES_DEV 1
1792 #define FS_BINARY_MOUNTDATA 2
1793 #define FS_HAS_SUBTYPE 4
1794 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
1795 #define FS_USERNS_DEV_MOUNT 16 /* A userns mount does not imply MNT_NODEV */
1796 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
1797 struct dentry *(*mount) (struct file_system_type *, int,
1798 const char *, void *);
1799 void (*kill_sb) (struct super_block *);
1800 struct module *owner;
1801 struct file_system_type * next;
1802 struct hlist_head fs_supers;
1804 struct lock_class_key s_lock_key;
1805 struct lock_class_key s_umount_key;
1806 struct lock_class_key s_vfs_rename_key;
1807 struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
1809 struct lock_class_key i_lock_key;
1810 struct lock_class_key i_mutex_key;
1811 struct lock_class_key i_mutex_dir_key;
1814 #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME)
1816 extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
1817 void *data, int (*fill_super)(struct super_block *, void *, int));
1818 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
1819 int flags, const char *dev_name, void *data,
1820 int (*fill_super)(struct super_block *, void *, int));
1821 extern struct dentry *mount_single(struct file_system_type *fs_type,
1822 int flags, void *data,
1823 int (*fill_super)(struct super_block *, void *, int));
1824 extern struct dentry *mount_nodev(struct file_system_type *fs_type,
1825 int flags, void *data,
1826 int (*fill_super)(struct super_block *, void *, int));
1827 extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
1828 void generic_shutdown_super(struct super_block *sb);
1829 void kill_block_super(struct super_block *sb);
1830 void kill_anon_super(struct super_block *sb);
1831 void kill_litter_super(struct super_block *sb);
1832 void deactivate_super(struct super_block *sb);
1833 void deactivate_locked_super(struct super_block *sb);
1834 int set_anon_super(struct super_block *s, void *data);
1835 int get_anon_bdev(dev_t *);
1836 void free_anon_bdev(dev_t);
1837 struct super_block *sget(struct file_system_type *type,
1838 int (*test)(struct super_block *,void *),
1839 int (*set)(struct super_block *,void *),
1840 int flags, void *data);
1841 extern struct dentry *mount_pseudo(struct file_system_type *, char *,
1842 const struct super_operations *ops,
1843 const struct dentry_operations *dops,
1846 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1847 #define fops_get(fops) \
1848 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1849 #define fops_put(fops) \
1850 do { if (fops) module_put((fops)->owner); } while(0)
1852 * This one is to be used *ONLY* from ->open() instances.
1853 * fops must be non-NULL, pinned down *and* module dependencies
1854 * should be sufficient to pin the caller down as well.
1856 #define replace_fops(f, fops) \
1858 struct file *__file = (f); \
1859 fops_put(__file->f_op); \
1860 BUG_ON(!(__file->f_op = (fops))); \
1863 extern int register_filesystem(struct file_system_type *);
1864 extern int unregister_filesystem(struct file_system_type *);
1865 extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
1866 #define kern_mount(type) kern_mount_data(type, NULL)
1867 extern void kern_unmount(struct vfsmount *mnt);
1868 extern int may_umount_tree(struct vfsmount *);
1869 extern int may_umount(struct vfsmount *);
1870 extern long do_mount(const char *, const char __user *,
1871 const char *, unsigned long, void *);
1872 extern struct vfsmount *collect_mounts(struct path *);
1873 extern void drop_collected_mounts(struct vfsmount *);
1874 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
1876 extern int vfs_statfs(struct path *, struct kstatfs *);
1877 extern int user_statfs(const char __user *, struct kstatfs *);
1878 extern int fd_statfs(int, struct kstatfs *);
1879 extern int vfs_ustat(dev_t, struct kstatfs *);
1880 extern int freeze_super(struct super_block *super);
1881 extern int thaw_super(struct super_block *super);
1882 extern bool our_mnt(struct vfsmount *mnt);
1883 extern bool fs_fully_visible(struct file_system_type *);
1885 extern int current_umask(void);
1887 extern void ihold(struct inode * inode);
1888 extern void iput(struct inode *);
1890 static inline struct inode *file_inode(const struct file *f)
1896 extern struct kobject *fs_kobj;
1898 #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
1900 #define FLOCK_VERIFY_READ 1
1901 #define FLOCK_VERIFY_WRITE 2
1903 #ifdef CONFIG_FILE_LOCKING
1904 extern int locks_mandatory_locked(struct file *);
1905 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1908 * Candidates for mandatory locking have the setgid bit set
1909 * but no group execute bit - an otherwise meaningless combination.
1912 static inline int __mandatory_lock(struct inode *ino)
1914 return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
1918 * ... and these candidates should be on MS_MANDLOCK mounted fs,
1919 * otherwise these will be advisory locks
1922 static inline int mandatory_lock(struct inode *ino)
1924 return IS_MANDLOCK(ino) && __mandatory_lock(ino);
1927 static inline int locks_verify_locked(struct file *file)
1929 if (mandatory_lock(file_inode(file)))
1930 return locks_mandatory_locked(file);
1934 static inline int locks_verify_truncate(struct inode *inode,
1938 if (inode->i_flock && mandatory_lock(inode))
1939 return locks_mandatory_area(
1940 FLOCK_VERIFY_WRITE, inode, filp,
1941 size < inode->i_size ? size : inode->i_size,
1942 (size < inode->i_size ? inode->i_size - size
1943 : size - inode->i_size)
1948 static inline int break_lease(struct inode *inode, unsigned int mode)
1951 * Since this check is lockless, we must ensure that any refcounts
1952 * taken are done before checking inode->i_flock. Otherwise, we could
1953 * end up racing with tasks trying to set a new lease on this file.
1957 return __break_lease(inode, mode, FL_LEASE);
1961 static inline int break_deleg(struct inode *inode, unsigned int mode)
1964 * Since this check is lockless, we must ensure that any refcounts
1965 * taken are done before checking inode->i_flock. Otherwise, we could
1966 * end up racing with tasks trying to set a new lease on this file.
1970 return __break_lease(inode, mode, FL_DELEG);
1974 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
1978 ret = break_deleg(inode, O_WRONLY|O_NONBLOCK);
1979 if (ret == -EWOULDBLOCK && delegated_inode) {
1980 *delegated_inode = inode;
1986 static inline int break_deleg_wait(struct inode **delegated_inode)
1990 ret = break_deleg(*delegated_inode, O_WRONLY);
1991 iput(*delegated_inode);
1992 *delegated_inode = NULL;
1996 #else /* !CONFIG_FILE_LOCKING */
1997 static inline int locks_mandatory_locked(struct file *file)
2002 static inline int locks_mandatory_area(int rw, struct inode *inode,
2003 struct file *filp, loff_t offset,
2009 static inline int __mandatory_lock(struct inode *inode)
2014 static inline int mandatory_lock(struct inode *inode)
2019 static inline int locks_verify_locked(struct file *file)
2024 static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
2030 static inline int break_lease(struct inode *inode, unsigned int mode)
2035 static inline int break_deleg(struct inode *inode, unsigned int mode)
2040 static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode)
2045 static inline int break_deleg_wait(struct inode **delegated_inode)
2051 #endif /* CONFIG_FILE_LOCKING */
2056 const char *name; /* pointer to actual string */
2057 const __user char *uptr; /* original userland pointer */
2058 struct audit_names *aname;
2059 bool separate; /* should "name" be freed? */
2062 extern long vfs_truncate(struct path *, loff_t);
2063 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
2065 extern int do_fallocate(struct file *file, int mode, loff_t offset,
2067 extern long do_sys_open(int dfd, const char __user *filename, int flags,
2069 extern struct file *file_open_name(struct filename *, int, umode_t);
2070 extern struct file *filp_open(const char *, int, umode_t);
2071 extern struct file *file_open_root(struct dentry *, struct vfsmount *,
2073 extern int vfs_open(const struct path *, struct file *, const struct cred *);
2074 extern struct file * dentry_open(const struct path *, int, const struct cred *);
2075 extern int filp_close(struct file *, fl_owner_t id);
2077 extern struct filename *getname(const char __user *);
2078 extern struct filename *getname_kernel(const char *);
2084 extern int finish_open(struct file *file, struct dentry *dentry,
2085 int (*open)(struct inode *, struct file *),
2087 extern int finish_no_open(struct file *file, struct dentry *dentry);
2091 extern int ioctl_preallocate(struct file *filp, void __user *argp);
2094 extern void __init vfs_caches_init_early(void);
2095 extern void __init vfs_caches_init(unsigned long);
2097 extern struct kmem_cache *names_cachep;
2099 extern void final_putname(struct filename *name);
2101 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
2102 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2103 #ifndef CONFIG_AUDITSYSCALL
2104 #define putname(name) final_putname(name)
2106 extern void putname(struct filename *name);
2110 extern int register_blkdev(unsigned int, const char *);
2111 extern void unregister_blkdev(unsigned int, const char *);
2112 extern struct block_device *bdget(dev_t);
2113 extern struct block_device *bdgrab(struct block_device *bdev);
2114 extern void bd_set_size(struct block_device *, loff_t size);
2115 extern void bd_forget(struct inode *inode);
2116 extern void bdput(struct block_device *);
2117 extern void invalidate_bdev(struct block_device *);
2118 extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
2119 extern int sync_blockdev(struct block_device *bdev);
2120 extern void kill_bdev(struct block_device *);
2121 extern struct super_block *freeze_bdev(struct block_device *);
2122 extern void emergency_thaw_all(void);
2123 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
2124 extern int fsync_bdev(struct block_device *);
2125 extern int sb_is_blkdev_sb(struct super_block *sb);
2127 static inline void bd_forget(struct inode *inode) {}
2128 static inline int sync_blockdev(struct block_device *bdev) { return 0; }
2129 static inline void kill_bdev(struct block_device *bdev) {}
2130 static inline void invalidate_bdev(struct block_device *bdev) {}
2132 static inline struct super_block *freeze_bdev(struct block_device *sb)
2137 static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
2142 static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
2146 static inline int sb_is_blkdev_sb(struct super_block *sb)
2151 extern int sync_filesystem(struct super_block *);
2152 extern const struct file_operations def_blk_fops;
2153 extern const struct file_operations def_chr_fops;
2154 extern const struct file_operations bad_sock_fops;
2156 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
2157 extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
2158 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
2159 extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
2160 extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
2162 extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
2164 extern void blkdev_put(struct block_device *bdev, fmode_t mode);
2166 extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
2167 extern void bd_unlink_disk_holder(struct block_device *bdev,
2168 struct gendisk *disk);
2170 static inline int bd_link_disk_holder(struct block_device *bdev,
2171 struct gendisk *disk)
2175 static inline void bd_unlink_disk_holder(struct block_device *bdev,
2176 struct gendisk *disk)
2183 #define CHRDEV_MAJOR_HASH_SIZE 255
2184 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2185 extern int register_chrdev_region(dev_t, unsigned, const char *);
2186 extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2187 unsigned int count, const char *name,
2188 const struct file_operations *fops);
2189 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2190 unsigned int count, const char *name);
2191 extern void unregister_chrdev_region(dev_t, unsigned);
2192 extern void chrdev_show(struct seq_file *,off_t);
2194 static inline int register_chrdev(unsigned int major, const char *name,
2195 const struct file_operations *fops)
2197 return __register_chrdev(major, 0, 256, name, fops);
2200 static inline void unregister_chrdev(unsigned int major, const char *name)
2202 __unregister_chrdev(major, 0, 256, name);
2205 /* fs/block_dev.c */
2206 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
2207 #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
2210 #define BLKDEV_MAJOR_HASH_SIZE 255
2211 extern const char *__bdevname(dev_t, char *buffer);
2212 extern const char *bdevname(struct block_device *bdev, char *buffer);
2213 extern struct block_device *lookup_bdev(const char *);
2214 extern void blkdev_show(struct seq_file *,off_t);
2217 #define BLKDEV_MAJOR_HASH_SIZE 0
2220 extern void init_special_inode(struct inode *, umode_t, dev_t);
2222 /* Invalid inode operations -- fs/bad_inode.c */
2223 extern void make_bad_inode(struct inode *);
2224 extern int is_bad_inode(struct inode *);
2228 * return READ, READA, or WRITE
2230 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
2233 * return data direction, READ or WRITE
2235 #define bio_data_dir(bio) ((bio)->bi_rw & 1)
2237 extern void check_disk_size_change(struct gendisk *disk,
2238 struct block_device *bdev);
2239 extern int revalidate_disk(struct gendisk *);
2240 extern int check_disk_change(struct block_device *);
2241 extern int __invalidate_device(struct block_device *, bool);
2242 extern int invalidate_partition(struct gendisk *, int);
2244 unsigned long invalidate_mapping_pages(struct address_space *mapping,
2245 pgoff_t start, pgoff_t end);
2247 static inline void invalidate_remote_inode(struct inode *inode)
2249 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2250 S_ISLNK(inode->i_mode))
2251 invalidate_mapping_pages(inode->i_mapping, 0, -1);
2253 extern int invalidate_inode_pages2(struct address_space *mapping);
2254 extern int invalidate_inode_pages2_range(struct address_space *mapping,
2255 pgoff_t start, pgoff_t end);
2256 extern int write_inode_now(struct inode *, int);
2257 extern int filemap_fdatawrite(struct address_space *);
2258 extern int filemap_flush(struct address_space *);
2259 extern int filemap_fdatawait(struct address_space *);
2260 extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
2262 extern int filemap_write_and_wait(struct address_space *mapping);
2263 extern int filemap_write_and_wait_range(struct address_space *mapping,
2264 loff_t lstart, loff_t lend);
2265 extern int __filemap_fdatawrite_range(struct address_space *mapping,
2266 loff_t start, loff_t end, int sync_mode);
2267 extern int filemap_fdatawrite_range(struct address_space *mapping,
2268 loff_t start, loff_t end);
2270 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2272 extern int vfs_fsync(struct file *file, int datasync);
2273 static inline int generic_write_sync(struct file *file, loff_t pos, loff_t count)
2275 if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
2277 return vfs_fsync_range(file, pos, pos + count - 1,
2278 (file->f_flags & __O_SYNC) ? 0 : 1);
2280 extern void emergency_sync(void);
2281 extern void emergency_remount(void);
2283 extern sector_t bmap(struct inode *, sector_t);
2285 extern int notify_change(struct dentry *, struct iattr *, struct inode **);
2286 extern int inode_permission(struct inode *, int);
2287 extern int __inode_permission(struct inode *, int);
2288 extern int generic_permission(struct inode *, int);
2289 extern int __check_sticky(struct inode *dir, struct inode *inode);
2291 static inline bool execute_ok(struct inode *inode)
2293 return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2296 static inline void file_start_write(struct file *file)
2298 if (!S_ISREG(file_inode(file)->i_mode))
2300 __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
2303 static inline bool file_start_write_trylock(struct file *file)
2305 if (!S_ISREG(file_inode(file)->i_mode))
2307 return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
2310 static inline void file_end_write(struct file *file)
2312 if (!S_ISREG(file_inode(file)->i_mode))
2314 __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
2318 * get_write_access() gets write permission for a file.
2319 * put_write_access() releases this write permission.
2320 * This is used for regular files.
2321 * We cannot support write (and maybe mmap read-write shared) accesses and
2322 * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode
2323 * can have the following values:
2324 * 0: no writers, no VM_DENYWRITE mappings
2325 * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist
2326 * > 0: (i_writecount) users are writing to the file.
2328 * Normally we operate on that counter with atomic_{inc,dec} and it's safe
2329 * except for the cases where we don't hold i_writecount yet. Then we need to
2330 * use {get,deny}_write_access() - these functions check the sign and refuse
2331 * to do the change if sign is wrong.
2333 static inline int get_write_access(struct inode *inode)
2335 return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
2337 static inline int deny_write_access(struct file *file)
2339 struct inode *inode = file_inode(file);
2340 return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY;
2342 static inline void put_write_access(struct inode * inode)
2344 atomic_dec(&inode->i_writecount);
2346 static inline void allow_write_access(struct file *file)
2349 atomic_inc(&file_inode(file)->i_writecount);
2351 static inline bool inode_is_open_for_write(const struct inode *inode)
2353 return atomic_read(&inode->i_writecount) > 0;
2357 static inline void i_readcount_dec(struct inode *inode)
2359 BUG_ON(!atomic_read(&inode->i_readcount));
2360 atomic_dec(&inode->i_readcount);
2362 static inline void i_readcount_inc(struct inode *inode)
2364 atomic_inc(&inode->i_readcount);
2367 static inline void i_readcount_dec(struct inode *inode)
2371 static inline void i_readcount_inc(struct inode *inode)
2376 extern int do_pipe_flags(int *, int);
2378 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
2379 extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
2380 extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
2381 extern struct file * open_exec(const char *);
2383 /* fs/dcache.c -- generic fs support functions */
2384 extern int is_subdir(struct dentry *, struct dentry *);
2385 extern int path_is_under(struct path *, struct path *);
2387 #include <linux/err.h>
2389 /* needed for stackable file system support */
2390 extern loff_t default_llseek(struct file *file, loff_t offset, int whence);
2392 extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence);
2394 extern int inode_init_always(struct super_block *, struct inode *);
2395 extern void inode_init_once(struct inode *);
2396 extern void address_space_init_once(struct address_space *mapping);
2397 extern struct inode * igrab(struct inode *);
2398 extern ino_t iunique(struct super_block *, ino_t);
2399 extern int inode_needs_sync(struct inode *inode);
2400 extern int generic_delete_inode(struct inode *inode);
2401 static inline int generic_drop_inode(struct inode *inode)
2403 return !inode->i_nlink || inode_unhashed(inode);
2406 extern struct inode *ilookup5_nowait(struct super_block *sb,
2407 unsigned long hashval, int (*test)(struct inode *, void *),
2409 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2410 int (*test)(struct inode *, void *), void *data);
2411 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2413 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2414 extern struct inode * iget_locked(struct super_block *, unsigned long);
2415 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2416 extern int insert_inode_locked(struct inode *);
2417 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2418 extern void lockdep_annotate_inode_mutex_key(struct inode *inode);
2420 static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
2422 extern void unlock_new_inode(struct inode *);
2423 extern unsigned int get_next_ino(void);
2425 extern void __iget(struct inode * inode);
2426 extern void iget_failed(struct inode *);
2427 extern void clear_inode(struct inode *);
2428 extern void __destroy_inode(struct inode *);
2429 extern struct inode *new_inode_pseudo(struct super_block *sb);
2430 extern struct inode *new_inode(struct super_block *sb);
2431 extern void free_inode_nonrcu(struct inode *inode);
2432 extern int should_remove_suid(struct dentry *);
2433 extern int file_remove_suid(struct file *);
2435 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2436 static inline void insert_inode_hash(struct inode *inode)
2438 __insert_inode_hash(inode, inode->i_ino);
2441 extern void __remove_inode_hash(struct inode *);
2442 static inline void remove_inode_hash(struct inode *inode)
2444 if (!inode_unhashed(inode))
2445 __remove_inode_hash(inode);
2448 extern void inode_sb_list_add(struct inode *inode);
2451 extern void submit_bio(int, struct bio *);
2452 extern int bdev_read_only(struct block_device *);
2454 extern int set_blocksize(struct block_device *, int);
2455 extern int sb_set_blocksize(struct super_block *, int);
2456 extern int sb_min_blocksize(struct super_block *, int);
2458 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2459 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2460 extern int generic_file_remap_pages(struct vm_area_struct *, unsigned long addr,
2461 unsigned long size, pgoff_t pgoff);
2462 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
2463 extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
2464 extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
2465 extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);
2466 extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *, loff_t);
2467 extern ssize_t generic_perform_write(struct file *, struct iov_iter *, loff_t);
2468 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
2469 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
2470 extern ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
2471 extern ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
2473 /* fs/block_dev.c */
2474 extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);
2475 extern ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from);
2476 extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
2478 extern void block_sync_page(struct page *page);
2481 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
2482 struct pipe_inode_info *, size_t, unsigned int);
2483 extern ssize_t default_file_splice_read(struct file *, loff_t *,
2484 struct pipe_inode_info *, size_t, unsigned int);
2485 extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
2486 struct file *, loff_t *, size_t, unsigned int);
2487 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2488 struct file *out, loff_t *, size_t len, unsigned int flags);
2489 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
2490 loff_t *opos, size_t len, unsigned int flags);
2494 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2495 extern loff_t noop_llseek(struct file *file, loff_t offset, int whence);
2496 extern loff_t no_llseek(struct file *file, loff_t offset, int whence);
2497 extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
2498 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
2499 extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
2500 int whence, loff_t maxsize, loff_t eof);
2501 extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
2502 int whence, loff_t size);
2503 extern int generic_file_open(struct inode * inode, struct file * filp);
2504 extern int nonseekable_open(struct inode * inode, struct file * filp);
2506 #ifdef CONFIG_FS_XIP
2507 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
2509 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
2510 extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
2511 size_t len, loff_t *ppos);
2512 extern int xip_truncate_page(struct address_space *mapping, loff_t from);
2514 static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
2521 typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
2522 loff_t file_offset);
2525 /* need locking between buffered and direct access */
2528 /* filesystem does not support filling holes */
2529 DIO_SKIP_HOLES = 0x02,
2531 /* filesystem can handle aio writes beyond i_size */
2532 DIO_ASYNC_EXTEND = 0x04,
2535 void dio_end_io(struct bio *bio, int error);
2537 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
2538 struct block_device *bdev, struct iov_iter *iter, loff_t offset,
2539 get_block_t get_block, dio_iodone_t end_io,
2540 dio_submit_t submit_io, int flags);
2542 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
2543 struct inode *inode, struct iov_iter *iter, loff_t offset,
2544 get_block_t get_block)
2546 return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iter,
2547 offset, get_block, NULL, NULL,
2548 DIO_LOCKING | DIO_SKIP_HOLES);
2552 void inode_dio_wait(struct inode *inode);
2553 void inode_dio_done(struct inode *inode);
2555 extern void inode_set_flags(struct inode *inode, unsigned int flags,
2558 extern const struct file_operations generic_ro_fops;
2560 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2562 extern int readlink_copy(char __user *, int, const char *);
2563 extern int page_readlink(struct dentry *, char __user *, int);
2564 extern void *page_follow_link_light(struct dentry *, struct nameidata *);
2565 extern void page_put_link(struct dentry *, struct nameidata *, void *);
2566 extern int __page_symlink(struct inode *inode, const char *symname, int len,
2568 extern int page_symlink(struct inode *inode, const char *symname, int len);
2569 extern const struct inode_operations page_symlink_inode_operations;
2570 extern void kfree_put_link(struct dentry *, struct nameidata *, void *);
2571 extern int generic_readlink(struct dentry *, char __user *, int);
2572 extern void generic_fillattr(struct inode *, struct kstat *);
2573 int vfs_getattr_nosec(struct path *path, struct kstat *stat);
2574 extern int vfs_getattr(struct path *, struct kstat *);
2575 void __inode_add_bytes(struct inode *inode, loff_t bytes);
2576 void inode_add_bytes(struct inode *inode, loff_t bytes);
2577 void __inode_sub_bytes(struct inode *inode, loff_t bytes);
2578 void inode_sub_bytes(struct inode *inode, loff_t bytes);
2579 loff_t inode_get_bytes(struct inode *inode);
2580 void inode_set_bytes(struct inode *inode, loff_t bytes);
2582 extern int vfs_readdir(struct file *, filldir_t, void *);
2583 extern int iterate_dir(struct file *, struct dir_context *);
2585 extern int vfs_stat(const char __user *, struct kstat *);
2586 extern int vfs_lstat(const char __user *, struct kstat *);
2587 extern int vfs_fstat(unsigned int, struct kstat *);
2588 extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
2590 extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
2592 extern int __generic_block_fiemap(struct inode *inode,
2593 struct fiemap_extent_info *fieinfo,
2594 loff_t start, loff_t len,
2595 get_block_t *get_block);
2596 extern int generic_block_fiemap(struct inode *inode,
2597 struct fiemap_extent_info *fieinfo, u64 start,
2598 u64 len, get_block_t *get_block);
2600 extern void get_filesystem(struct file_system_type *fs);
2601 extern void put_filesystem(struct file_system_type *fs);
2602 extern struct file_system_type *get_fs_type(const char *name);
2603 extern struct super_block *get_super(struct block_device *);
2604 extern struct super_block *get_super_thawed(struct block_device *);
2605 extern struct super_block *get_active_super(struct block_device *bdev);
2606 extern void drop_super(struct super_block *sb);
2607 extern void iterate_supers(void (*)(struct super_block *, void *), void *);
2608 extern void iterate_supers_type(struct file_system_type *,
2609 void (*)(struct super_block *, void *), void *);
2611 extern int dcache_dir_open(struct inode *, struct file *);
2612 extern int dcache_dir_close(struct inode *, struct file *);
2613 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2614 extern int dcache_readdir(struct file *, struct dir_context *);
2615 extern int simple_setattr(struct dentry *, struct iattr *);
2616 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
2617 extern int simple_statfs(struct dentry *, struct kstatfs *);
2618 extern int simple_open(struct inode *inode, struct file *file);
2619 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
2620 extern int simple_unlink(struct inode *, struct dentry *);
2621 extern int simple_rmdir(struct inode *, struct dentry *);
2622 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
2623 extern int noop_fsync(struct file *, loff_t, loff_t, int);
2624 extern int simple_empty(struct dentry *);
2625 extern int simple_readpage(struct file *file, struct page *page);
2626 extern int simple_write_begin(struct file *file, struct address_space *mapping,
2627 loff_t pos, unsigned len, unsigned flags,
2628 struct page **pagep, void **fsdata);
2629 extern int simple_write_end(struct file *file, struct address_space *mapping,
2630 loff_t pos, unsigned len, unsigned copied,
2631 struct page *page, void *fsdata);
2632 extern int always_delete_dentry(const struct dentry *);
2633 extern struct inode *alloc_anon_inode(struct super_block *);
2634 extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
2635 extern const struct dentry_operations simple_dentry_operations;
2637 extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);
2638 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2639 extern const struct file_operations simple_dir_operations;
2640 extern const struct inode_operations simple_dir_inode_operations;
2641 struct tree_descr { char *name; const struct file_operations *ops; int mode; };
2642 struct dentry *d_alloc_name(struct dentry *, const char *);
2643 extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
2644 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2645 extern void simple_release_fs(struct vfsmount **mount, int *count);
2647 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2648 loff_t *ppos, const void *from, size_t available);
2649 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
2650 const void __user *from, size_t count);
2652 extern int __generic_file_fsync(struct file *, loff_t, loff_t, int);
2653 extern int generic_file_fsync(struct file *, loff_t, loff_t, int);
2655 extern int generic_check_addressable(unsigned, u64);
2657 #ifdef CONFIG_MIGRATION
2658 extern int buffer_migrate_page(struct address_space *,
2659 struct page *, struct page *,
2662 #define buffer_migrate_page NULL
2665 extern int inode_change_ok(const struct inode *, struct iattr *);
2666 extern int inode_newsize_ok(const struct inode *, loff_t offset);
2667 extern void setattr_copy(struct inode *inode, const struct iattr *attr);
2669 extern int file_update_time(struct file *file);
2671 extern int generic_show_options(struct seq_file *m, struct dentry *root);
2672 extern void save_mount_options(struct super_block *sb, char *options);
2673 extern void replace_mount_options(struct super_block *sb, char *options);
2675 static inline ino_t parent_ino(struct dentry *dentry)
2680 * Don't strictly need d_lock here? If the parent ino could change
2681 * then surely we'd have a deeper race in the caller?
2683 spin_lock(&dentry->d_lock);
2684 res = dentry->d_parent->d_inode->i_ino;
2685 spin_unlock(&dentry->d_lock);
2689 /* Transaction based IO helpers */
2692 * An argresp is stored in an allocated page and holds the
2693 * size of the argument or response, along with its content
2695 struct simple_transaction_argresp {
2700 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
2702 char *simple_transaction_get(struct file *file, const char __user *buf,
2704 ssize_t simple_transaction_read(struct file *file, char __user *buf,
2705 size_t size, loff_t *pos);
2706 int simple_transaction_release(struct inode *inode, struct file *file);
2708 void simple_transaction_set(struct file *file, size_t n);
2711 * simple attribute files
2713 * These attributes behave similar to those in sysfs:
2715 * Writing to an attribute immediately sets a value, an open file can be
2716 * written to multiple times.
2718 * Reading from an attribute creates a buffer from the value that might get
2719 * read with multiple read calls. When the attribute has been read
2720 * completely, no further read calls are possible until the file is opened
2723 * All attributes contain a text representation of a numeric value
2724 * that are accessed with the get() and set() functions.
2726 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
2727 static int __fops ## _open(struct inode *inode, struct file *file) \
2729 __simple_attr_check_format(__fmt, 0ull); \
2730 return simple_attr_open(inode, file, __get, __set, __fmt); \
2732 static const struct file_operations __fops = { \
2733 .owner = THIS_MODULE, \
2734 .open = __fops ## _open, \
2735 .release = simple_attr_release, \
2736 .read = simple_attr_read, \
2737 .write = simple_attr_write, \
2738 .llseek = generic_file_llseek, \
2741 static inline __printf(1, 2)
2742 void __simple_attr_check_format(const char *fmt, ...)
2744 /* don't do anything, just let the compiler check the arguments; */
2747 int simple_attr_open(struct inode *inode, struct file *file,
2748 int (*get)(void *, u64 *), int (*set)(void *, u64),
2750 int simple_attr_release(struct inode *inode, struct file *file);
2751 ssize_t simple_attr_read(struct file *file, char __user *buf,
2752 size_t len, loff_t *ppos);
2753 ssize_t simple_attr_write(struct file *file, const char __user *buf,
2754 size_t len, loff_t *ppos);
2757 int proc_nr_files(struct ctl_table *table, int write,
2758 void __user *buffer, size_t *lenp, loff_t *ppos);
2759 int proc_nr_dentry(struct ctl_table *table, int write,
2760 void __user *buffer, size_t *lenp, loff_t *ppos);
2761 int proc_nr_inodes(struct ctl_table *table, int write,
2762 void __user *buffer, size_t *lenp, loff_t *ppos);
2763 int __init get_filesystem_list(char *buf);
2765 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
2766 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
2768 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
2769 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
2770 (flag & __FMODE_NONOTIFY)))
2772 static inline int is_sxid(umode_t mode)
2774 return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
2777 static inline int check_sticky(struct inode *dir, struct inode *inode)
2779 if (!(dir->i_mode & S_ISVTX))
2782 return __check_sticky(dir, inode);
2785 static inline void inode_has_no_xattr(struct inode *inode)
2787 if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC))
2788 inode->i_flags |= S_NOSEC;
2791 static inline bool dir_emit(struct dir_context *ctx,
2792 const char *name, int namelen,
2793 u64 ino, unsigned type)
2795 return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
2797 static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
2799 return ctx->actor(ctx, ".", 1, ctx->pos,
2800 file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
2802 static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
2804 return ctx->actor(ctx, "..", 2, ctx->pos,
2805 parent_ino(file->f_path.dentry), DT_DIR) == 0;
2807 static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
2809 if (ctx->pos == 0) {
2810 if (!dir_emit_dot(file, ctx))
2814 if (ctx->pos == 1) {
2815 if (!dir_emit_dotdot(file, ctx))
2821 static inline bool dir_relax(struct inode *inode)
2823 mutex_unlock(&inode->i_mutex);
2824 mutex_lock(&inode->i_mutex);
2825 return !IS_DEADDIR(inode);
2828 #endif /* _LINUX_FS_H */