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1 #ifndef _LINUX_FS_H
2 #define _LINUX_FS_H
3
4 /*
5 * This file has definitions for some important file table
6 * structures etc.
7 */
8
9 #include <linux/limits.h>
10 #include <linux/ioctl.h>
11 #include <linux/blk_types.h>
12 #include <linux/types.h>
13
14 /*
15 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
16 * the file limit at runtime and only root can increase the per-process
17 * nr_file rlimit, so it's safe to set up a ridiculously high absolute
18 * upper limit on files-per-process.
19 *
20 * Some programs (notably those using select()) may have to be
21 * recompiled to take full advantage of the new limits..
22 */
23
24 /* Fixed constants first: */
25 #undef NR_OPEN
26 #define INR_OPEN 1024 /* Initial setting for nfile rlimits */
27
28 #define BLOCK_SIZE_BITS 10
29 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
30
31 #define SEEK_SET 0 /* seek relative to beginning of file */
32 #define SEEK_CUR 1 /* seek relative to current file position */
33 #define SEEK_END 2 /* seek relative to end of file */
34 #define SEEK_MAX SEEK_END
35
36 struct fstrim_range {
37 __u64 start;
38 __u64 len;
39 __u64 minlen;
40 };
41
42 /* And dynamically-tunable limits and defaults: */
43 struct files_stat_struct {
44 unsigned long nr_files; /* read only */
45 unsigned long nr_free_files; /* read only */
46 unsigned long max_files; /* tunable */
47 };
48
49 struct inodes_stat_t {
50 int nr_inodes;
51 int nr_unused;
52 int dummy[5]; /* padding for sysctl ABI compatibility */
53 };
54
55
56 #define NR_FILE 8192 /* this can well be larger on a larger system */
57
58 #define MAY_EXEC 1
59 #define MAY_WRITE 2
60 #define MAY_READ 4
61 #define MAY_APPEND 8
62 #define MAY_ACCESS 16
63 #define MAY_OPEN 32
64 #define MAY_CHDIR 64
65
66 /*
67 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond
68 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open()
69 */
70
71 /* file is open for reading */
72 #define FMODE_READ ((__force fmode_t)0x1)
73 /* file is open for writing */
74 #define FMODE_WRITE ((__force fmode_t)0x2)
75 /* file is seekable */
76 #define FMODE_LSEEK ((__force fmode_t)0x4)
77 /* file can be accessed using pread */
78 #define FMODE_PREAD ((__force fmode_t)0x8)
79 /* file can be accessed using pwrite */
80 #define FMODE_PWRITE ((__force fmode_t)0x10)
81 /* File is opened for execution with sys_execve / sys_uselib */
82 #define FMODE_EXEC ((__force fmode_t)0x20)
83 /* File is opened with O_NDELAY (only set for block devices) */
84 #define FMODE_NDELAY ((__force fmode_t)0x40)
85 /* File is opened with O_EXCL (only set for block devices) */
86 #define FMODE_EXCL ((__force fmode_t)0x80)
87 /* File is opened using open(.., 3, ..) and is writeable only for ioctls
88 (specialy hack for floppy.c) */
89 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100)
90
91 /*
92 * Don't update ctime and mtime.
93 *
94 * Currently a special hack for the XFS open_by_handle ioctl, but we'll
95 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
96 */
97 #define FMODE_NOCMTIME ((__force fmode_t)0x800)
98
99 /* Expect random access pattern */
100 #define FMODE_RANDOM ((__force fmode_t)0x1000)
101
102 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */
103 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000)
104
105 /* File is opened with O_PATH; almost nothing can be done with it */
106 #define FMODE_PATH ((__force fmode_t)0x4000)
107
108 /* File was opened by fanotify and shouldn't generate fanotify events */
109 #define FMODE_NONOTIFY ((__force fmode_t)0x1000000)
110
111 /*
112 * The below are the various read and write types that we support. Some of
113 * them include behavioral modifiers that send information down to the
114 * block layer and IO scheduler. Terminology:
115 *
116 * The block layer uses device plugging to defer IO a little bit, in
117 * the hope that we will see more IO very shortly. This increases
118 * coalescing of adjacent IO and thus reduces the number of IOs we
119 * have to send to the device. It also allows for better queuing,
120 * if the IO isn't mergeable. If the caller is going to be waiting
121 * for the IO, then he must ensure that the device is unplugged so
122 * that the IO is dispatched to the driver.
123 *
124 * All IO is handled async in Linux. This is fine for background
125 * writes, but for reads or writes that someone waits for completion
126 * on, we want to notify the block layer and IO scheduler so that they
127 * know about it. That allows them to make better scheduling
128 * decisions. So when the below references 'sync' and 'async', it
129 * is referencing this priority hint.
130 *
131 * With that in mind, the available types are:
132 *
133 * READ A normal read operation. Device will be plugged.
134 * READ_SYNC A synchronous read. Device is not plugged, caller can
135 * immediately wait on this read without caring about
136 * unplugging.
137 * READA Used for read-ahead operations. Lower priority, and the
138 * block layer could (in theory) choose to ignore this
139 * request if it runs into resource problems.
140 * WRITE A normal async write. Device will be plugged.
141 * WRITE_SYNC_PLUG Synchronous write. Identical to WRITE, but passes down
142 * the hint that someone will be waiting on this IO
143 * shortly. The device must still be unplugged explicitly,
144 * WRITE_SYNC_PLUG does not do this as we could be
145 * submitting more writes before we actually wait on any
146 * of them.
147 * WRITE_SYNC Like WRITE_SYNC_PLUG, but also unplugs the device
148 * immediately after submission. The write equivalent
149 * of READ_SYNC.
150 * WRITE_ODIRECT_PLUG Special case write for O_DIRECT only.
151 * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush.
152 * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on
153 * non-volatile media on completion.
154 * WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded
155 * by a cache flush and data is guaranteed to be on
156 * non-volatile media on completion.
157 *
158 */
159 #define RW_MASK REQ_WRITE
160 #define RWA_MASK REQ_RAHEAD
161
162 #define READ 0
163 #define WRITE RW_MASK
164 #define READA RWA_MASK
165
166 #define READ_SYNC (READ | REQ_SYNC | REQ_UNPLUG)
167 #define READ_META (READ | REQ_META)
168 #define WRITE_SYNC_PLUG (WRITE | REQ_SYNC | REQ_NOIDLE)
169 #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG)
170 #define WRITE_ODIRECT_PLUG (WRITE | REQ_SYNC)
171 #define WRITE_META (WRITE | REQ_META)
172 #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
173 REQ_FLUSH)
174 #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
175 REQ_FUA)
176 #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
177 REQ_FLUSH | REQ_FUA)
178
179 #define SEL_IN 1
180 #define SEL_OUT 2
181 #define SEL_EX 4
182
183 /* public flags for file_system_type */
184 #define FS_REQUIRES_DEV 1
185 #define FS_BINARY_MOUNTDATA 2
186 #define FS_HAS_SUBTYPE 4
187 #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
188 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move()
189 * during rename() internally.
190 */
191
192 /*
193 * These are the fs-independent mount-flags: up to 32 flags are supported
194 */
195 #define MS_RDONLY 1 /* Mount read-only */
196 #define MS_NOSUID 2 /* Ignore suid and sgid bits */
197 #define MS_NODEV 4 /* Disallow access to device special files */
198 #define MS_NOEXEC 8 /* Disallow program execution */
199 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */
200 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */
201 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
202 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */
203 #define MS_NOATIME 1024 /* Do not update access times. */
204 #define MS_NODIRATIME 2048 /* Do not update directory access times */
205 #define MS_BIND 4096
206 #define MS_MOVE 8192
207 #define MS_REC 16384
208 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence.
209 MS_VERBOSE is deprecated. */
210 #define MS_SILENT 32768
211 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
212 #define MS_UNBINDABLE (1<<17) /* change to unbindable */
213 #define MS_PRIVATE (1<<18) /* change to private */
214 #define MS_SLAVE (1<<19) /* change to slave */
215 #define MS_SHARED (1<<20) /* change to shared */
216 #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */
217 #define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */
218 #define MS_I_VERSION (1<<23) /* Update inode I_version field */
219 #define MS_STRICTATIME (1<<24) /* Always perform atime updates */
220 #define MS_BORN (1<<29)
221 #define MS_ACTIVE (1<<30)
222 #define MS_NOUSER (1<<31)
223
224 /*
225 * Superblock flags that can be altered by MS_REMOUNT
226 */
227 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION)
228
229 /*
230 * Old magic mount flag and mask
231 */
232 #define MS_MGC_VAL 0xC0ED0000
233 #define MS_MGC_MSK 0xffff0000
234
235 /* Inode flags - they have nothing to superblock flags now */
236
237 #define S_SYNC 1 /* Writes are synced at once */
238 #define S_NOATIME 2 /* Do not update access times */
239 #define S_APPEND 4 /* Append-only file */
240 #define S_IMMUTABLE 8 /* Immutable file */
241 #define S_DEAD 16 /* removed, but still open directory */
242 #define S_NOQUOTA 32 /* Inode is not counted to quota */
243 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
244 #define S_NOCMTIME 128 /* Do not update file c/mtime */
245 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
246 #define S_PRIVATE 512 /* Inode is fs-internal */
247 #define S_IMA 1024 /* Inode has an associated IMA struct */
248 #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */
249
250 /*
251 * Note that nosuid etc flags are inode-specific: setting some file-system
252 * flags just means all the inodes inherit those flags by default. It might be
253 * possible to override it selectively if you really wanted to with some
254 * ioctl() that is not currently implemented.
255 *
256 * Exception: MS_RDONLY is always applied to the entire file system.
257 *
258 * Unfortunately, it is possible to change a filesystems flags with it mounted
259 * with files in use. This means that all of the inodes will not have their
260 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
261 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
262 */
263 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
264
265 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
266 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
267 ((inode)->i_flags & S_SYNC))
268 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
269 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
270 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
271 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
272 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
273
274 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
275 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
276 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
277 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
278
279 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
280 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
281 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
282 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
283 #define IS_IMA(inode) ((inode)->i_flags & S_IMA)
284 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
285
286 /* the read-only stuff doesn't really belong here, but any other place is
287 probably as bad and I don't want to create yet another include file. */
288
289 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
290 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
291 #define BLKRRPART _IO(0x12,95) /* re-read partition table */
292 #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
293 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
294 #define BLKRASET _IO(0x12,98) /* set read ahead for block device */
295 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
296 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
297 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
298 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
299 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
300 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
301 #if 0
302 #define BLKPG _IO(0x12,105)/* See blkpg.h */
303
304 /* Some people are morons. Do not use sizeof! */
305
306 #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
307 #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
308 /* This was here just to show that the number is taken -
309 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
310 #endif
311 /* A jump here: 108-111 have been used for various private purposes. */
312 #define BLKBSZGET _IOR(0x12,112,size_t)
313 #define BLKBSZSET _IOW(0x12,113,size_t)
314 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
315 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
316 #define BLKTRACESTART _IO(0x12,116)
317 #define BLKTRACESTOP _IO(0x12,117)
318 #define BLKTRACETEARDOWN _IO(0x12,118)
319 #define BLKDISCARD _IO(0x12,119)
320 #define BLKIOMIN _IO(0x12,120)
321 #define BLKIOOPT _IO(0x12,121)
322 #define BLKALIGNOFF _IO(0x12,122)
323 #define BLKPBSZGET _IO(0x12,123)
324 #define BLKDISCARDZEROES _IO(0x12,124)
325 #define BLKSECDISCARD _IO(0x12,125)
326
327 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
328 #define FIBMAP _IO(0x00,1) /* bmap access */
329 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
330 #define FIFREEZE _IOWR('X', 119, int) /* Freeze */
331 #define FITHAW _IOWR('X', 120, int) /* Thaw */
332 #define FITRIM _IOWR('X', 121, struct fstrim_range) /* Trim */
333
334 #define FS_IOC_GETFLAGS _IOR('f', 1, long)
335 #define FS_IOC_SETFLAGS _IOW('f', 2, long)
336 #define FS_IOC_GETVERSION _IOR('v', 1, long)
337 #define FS_IOC_SETVERSION _IOW('v', 2, long)
338 #define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap)
339 #define FS_IOC32_GETFLAGS _IOR('f', 1, int)
340 #define FS_IOC32_SETFLAGS _IOW('f', 2, int)
341 #define FS_IOC32_GETVERSION _IOR('v', 1, int)
342 #define FS_IOC32_SETVERSION _IOW('v', 2, int)
343
344 /*
345 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
346 */
347 #define FS_SECRM_FL 0x00000001 /* Secure deletion */
348 #define FS_UNRM_FL 0x00000002 /* Undelete */
349 #define FS_COMPR_FL 0x00000004 /* Compress file */
350 #define FS_SYNC_FL 0x00000008 /* Synchronous updates */
351 #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */
352 #define FS_APPEND_FL 0x00000020 /* writes to file may only append */
353 #define FS_NODUMP_FL 0x00000040 /* do not dump file */
354 #define FS_NOATIME_FL 0x00000080 /* do not update atime */
355 /* Reserved for compression usage... */
356 #define FS_DIRTY_FL 0x00000100
357 #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
358 #define FS_NOCOMP_FL 0x00000400 /* Don't compress */
359 #define FS_ECOMPR_FL 0x00000800 /* Compression error */
360 /* End compression flags --- maybe not all used */
361 #define FS_BTREE_FL 0x00001000 /* btree format dir */
362 #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */
363 #define FS_IMAGIC_FL 0x00002000 /* AFS directory */
364 #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
365 #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */
366 #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
367 #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
368 #define FS_EXTENT_FL 0x00080000 /* Extents */
369 #define FS_DIRECTIO_FL 0x00100000 /* Use direct i/o */
370 #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
371
372 #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
373 #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
374
375
376 #define SYNC_FILE_RANGE_WAIT_BEFORE 1
377 #define SYNC_FILE_RANGE_WRITE 2
378 #define SYNC_FILE_RANGE_WAIT_AFTER 4
379
380 #ifdef __KERNEL__
381
382 #include <linux/linkage.h>
383 #include <linux/wait.h>
384 #include <linux/types.h>
385 #include <linux/kdev_t.h>
386 #include <linux/dcache.h>
387 #include <linux/path.h>
388 #include <linux/stat.h>
389 #include <linux/cache.h>
390 #include <linux/list.h>
391 #include <linux/radix-tree.h>
392 #include <linux/prio_tree.h>
393 #include <linux/init.h>
394 #include <linux/pid.h>
395 #include <linux/mutex.h>
396 #include <linux/capability.h>
397 #include <linux/semaphore.h>
398 #include <linux/fiemap.h>
399 #include <linux/rculist_bl.h>
400
401 #include <asm/atomic.h>
402 #include <asm/byteorder.h>
403
404 struct export_operations;
405 struct hd_geometry;
406 struct iovec;
407 struct nameidata;
408 struct kiocb;
409 struct kobject;
410 struct pipe_inode_info;
411 struct poll_table_struct;
412 struct kstatfs;
413 struct vm_area_struct;
414 struct vfsmount;
415 struct cred;
416
417 extern void __init inode_init(void);
418 extern void __init inode_init_early(void);
419 extern void __init files_init(unsigned long);
420
421 extern struct files_stat_struct files_stat;
422 extern unsigned long get_max_files(void);
423 extern int sysctl_nr_open;
424 extern struct inodes_stat_t inodes_stat;
425 extern int leases_enable, lease_break_time;
426
427 struct buffer_head;
428 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
429 struct buffer_head *bh_result, int create);
430 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
431 ssize_t bytes, void *private, int ret,
432 bool is_async);
433
434 /*
435 * Attribute flags. These should be or-ed together to figure out what
436 * has been changed!
437 */
438 #define ATTR_MODE (1 << 0)
439 #define ATTR_UID (1 << 1)
440 #define ATTR_GID (1 << 2)
441 #define ATTR_SIZE (1 << 3)
442 #define ATTR_ATIME (1 << 4)
443 #define ATTR_MTIME (1 << 5)
444 #define ATTR_CTIME (1 << 6)
445 #define ATTR_ATIME_SET (1 << 7)
446 #define ATTR_MTIME_SET (1 << 8)
447 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
448 #define ATTR_ATTR_FLAG (1 << 10)
449 #define ATTR_KILL_SUID (1 << 11)
450 #define ATTR_KILL_SGID (1 << 12)
451 #define ATTR_FILE (1 << 13)
452 #define ATTR_KILL_PRIV (1 << 14)
453 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
454 #define ATTR_TIMES_SET (1 << 16)
455
456 /*
457 * This is the Inode Attributes structure, used for notify_change(). It
458 * uses the above definitions as flags, to know which values have changed.
459 * Also, in this manner, a Filesystem can look at only the values it cares
460 * about. Basically, these are the attributes that the VFS layer can
461 * request to change from the FS layer.
462 *
463 * Derek Atkins <warlord@MIT.EDU> 94-10-20
464 */
465 struct iattr {
466 unsigned int ia_valid;
467 umode_t ia_mode;
468 uid_t ia_uid;
469 gid_t ia_gid;
470 loff_t ia_size;
471 struct timespec ia_atime;
472 struct timespec ia_mtime;
473 struct timespec ia_ctime;
474
475 /*
476 * Not an attribute, but an auxilary info for filesystems wanting to
477 * implement an ftruncate() like method. NOTE: filesystem should
478 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
479 */
480 struct file *ia_file;
481 };
482
483 /*
484 * Includes for diskquotas.
485 */
486 #include <linux/quota.h>
487
488 /**
489 * enum positive_aop_returns - aop return codes with specific semantics
490 *
491 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
492 * completed, that the page is still locked, and
493 * should be considered active. The VM uses this hint
494 * to return the page to the active list -- it won't
495 * be a candidate for writeback again in the near
496 * future. Other callers must be careful to unlock
497 * the page if they get this return. Returned by
498 * writepage();
499 *
500 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
501 * unlocked it and the page might have been truncated.
502 * The caller should back up to acquiring a new page and
503 * trying again. The aop will be taking reasonable
504 * precautions not to livelock. If the caller held a page
505 * reference, it should drop it before retrying. Returned
506 * by readpage().
507 *
508 * address_space_operation functions return these large constants to indicate
509 * special semantics to the caller. These are much larger than the bytes in a
510 * page to allow for functions that return the number of bytes operated on in a
511 * given page.
512 */
513
514 enum positive_aop_returns {
515 AOP_WRITEPAGE_ACTIVATE = 0x80000,
516 AOP_TRUNCATED_PAGE = 0x80001,
517 };
518
519 #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
520 #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
521 #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct
522 * helper code (eg buffer layer)
523 * to clear GFP_FS from alloc */
524
525 /*
526 * oh the beauties of C type declarations.
527 */
528 struct page;
529 struct address_space;
530 struct writeback_control;
531
532 struct iov_iter {
533 const struct iovec *iov;
534 unsigned long nr_segs;
535 size_t iov_offset;
536 size_t count;
537 };
538
539 size_t iov_iter_copy_from_user_atomic(struct page *page,
540 struct iov_iter *i, unsigned long offset, size_t bytes);
541 size_t iov_iter_copy_from_user(struct page *page,
542 struct iov_iter *i, unsigned long offset, size_t bytes);
543 void iov_iter_advance(struct iov_iter *i, size_t bytes);
544 int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
545 size_t iov_iter_single_seg_count(struct iov_iter *i);
546
547 static inline void iov_iter_init(struct iov_iter *i,
548 const struct iovec *iov, unsigned long nr_segs,
549 size_t count, size_t written)
550 {
551 i->iov = iov;
552 i->nr_segs = nr_segs;
553 i->iov_offset = 0;
554 i->count = count + written;
555
556 iov_iter_advance(i, written);
557 }
558
559 static inline size_t iov_iter_count(struct iov_iter *i)
560 {
561 return i->count;
562 }
563
564 /*
565 * "descriptor" for what we're up to with a read.
566 * This allows us to use the same read code yet
567 * have multiple different users of the data that
568 * we read from a file.
569 *
570 * The simplest case just copies the data to user
571 * mode.
572 */
573 typedef struct {
574 size_t written;
575 size_t count;
576 union {
577 char __user *buf;
578 void *data;
579 } arg;
580 int error;
581 } read_descriptor_t;
582
583 typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
584 unsigned long, unsigned long);
585
586 struct address_space_operations {
587 int (*writepage)(struct page *page, struct writeback_control *wbc);
588 int (*readpage)(struct file *, struct page *);
589 void (*sync_page)(struct page *);
590
591 /* Write back some dirty pages from this mapping. */
592 int (*writepages)(struct address_space *, struct writeback_control *);
593
594 /* Set a page dirty. Return true if this dirtied it */
595 int (*set_page_dirty)(struct page *page);
596
597 int (*readpages)(struct file *filp, struct address_space *mapping,
598 struct list_head *pages, unsigned nr_pages);
599
600 int (*write_begin)(struct file *, struct address_space *mapping,
601 loff_t pos, unsigned len, unsigned flags,
602 struct page **pagep, void **fsdata);
603 int (*write_end)(struct file *, struct address_space *mapping,
604 loff_t pos, unsigned len, unsigned copied,
605 struct page *page, void *fsdata);
606
607 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
608 sector_t (*bmap)(struct address_space *, sector_t);
609 void (*invalidatepage) (struct page *, unsigned long);
610 int (*releasepage) (struct page *, gfp_t);
611 void (*freepage)(struct page *);
612 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
613 loff_t offset, unsigned long nr_segs);
614 int (*get_xip_mem)(struct address_space *, pgoff_t, int,
615 void **, unsigned long *);
616 /* migrate the contents of a page to the specified target */
617 int (*migratepage) (struct address_space *,
618 struct page *, struct page *);
619 int (*launder_page) (struct page *);
620 int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
621 unsigned long);
622 int (*error_remove_page)(struct address_space *, struct page *);
623 };
624
625 /*
626 * pagecache_write_begin/pagecache_write_end must be used by general code
627 * to write into the pagecache.
628 */
629 int pagecache_write_begin(struct file *, struct address_space *mapping,
630 loff_t pos, unsigned len, unsigned flags,
631 struct page **pagep, void **fsdata);
632
633 int pagecache_write_end(struct file *, struct address_space *mapping,
634 loff_t pos, unsigned len, unsigned copied,
635 struct page *page, void *fsdata);
636
637 struct backing_dev_info;
638 struct address_space {
639 struct inode *host; /* owner: inode, block_device */
640 struct radix_tree_root page_tree; /* radix tree of all pages */
641 spinlock_t tree_lock; /* and lock protecting it */
642 unsigned int i_mmap_writable;/* count VM_SHARED mappings */
643 struct prio_tree_root i_mmap; /* tree of private and shared mappings */
644 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
645 spinlock_t i_mmap_lock; /* protect tree, count, list */
646 unsigned int truncate_count; /* Cover race condition with truncate */
647 unsigned long nrpages; /* number of total pages */
648 pgoff_t writeback_index;/* writeback starts here */
649 const struct address_space_operations *a_ops; /* methods */
650 unsigned long flags; /* error bits/gfp mask */
651 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
652 spinlock_t private_lock; /* for use by the address_space */
653 struct list_head private_list; /* ditto */
654 struct address_space *assoc_mapping; /* ditto */
655 struct mutex unmap_mutex; /* to protect unmapping */
656 } __attribute__((aligned(sizeof(long))));
657 /*
658 * On most architectures that alignment is already the case; but
659 * must be enforced here for CRIS, to let the least signficant bit
660 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
661 */
662
663 struct block_device {
664 dev_t bd_dev; /* not a kdev_t - it's a search key */
665 struct inode * bd_inode; /* will die */
666 struct super_block * bd_super;
667 int bd_openers;
668 struct mutex bd_mutex; /* open/close mutex */
669 struct list_head bd_inodes;
670 void * bd_claiming;
671 void * bd_holder;
672 int bd_holders;
673 bool bd_write_holder;
674 #ifdef CONFIG_SYSFS
675 struct list_head bd_holder_disks;
676 #endif
677 struct block_device * bd_contains;
678 unsigned bd_block_size;
679 struct hd_struct * bd_part;
680 /* number of times partitions within this device have been opened. */
681 unsigned bd_part_count;
682 int bd_invalidated;
683 struct gendisk * bd_disk;
684 struct list_head bd_list;
685 /*
686 * Private data. You must have bd_claim'ed the block_device
687 * to use this. NOTE: bd_claim allows an owner to claim
688 * the same device multiple times, the owner must take special
689 * care to not mess up bd_private for that case.
690 */
691 unsigned long bd_private;
692
693 /* The counter of freeze processes */
694 int bd_fsfreeze_count;
695 /* Mutex for freeze */
696 struct mutex bd_fsfreeze_mutex;
697 };
698
699 /*
700 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
701 * radix trees
702 */
703 #define PAGECACHE_TAG_DIRTY 0
704 #define PAGECACHE_TAG_WRITEBACK 1
705 #define PAGECACHE_TAG_TOWRITE 2
706
707 int mapping_tagged(struct address_space *mapping, int tag);
708
709 /*
710 * Might pages of this file be mapped into userspace?
711 */
712 static inline int mapping_mapped(struct address_space *mapping)
713 {
714 return !prio_tree_empty(&mapping->i_mmap) ||
715 !list_empty(&mapping->i_mmap_nonlinear);
716 }
717
718 /*
719 * Might pages of this file have been modified in userspace?
720 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
721 * marks vma as VM_SHARED if it is shared, and the file was opened for
722 * writing i.e. vma may be mprotected writable even if now readonly.
723 */
724 static inline int mapping_writably_mapped(struct address_space *mapping)
725 {
726 return mapping->i_mmap_writable != 0;
727 }
728
729 /*
730 * Use sequence counter to get consistent i_size on 32-bit processors.
731 */
732 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
733 #include <linux/seqlock.h>
734 #define __NEED_I_SIZE_ORDERED
735 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
736 #else
737 #define i_size_ordered_init(inode) do { } while (0)
738 #endif
739
740 struct posix_acl;
741 #define ACL_NOT_CACHED ((void *)(-1))
742
743 struct inode {
744 /* RCU path lookup touches following: */
745 umode_t i_mode;
746 uid_t i_uid;
747 gid_t i_gid;
748 const struct inode_operations *i_op;
749 struct super_block *i_sb;
750
751 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
752 unsigned int i_flags;
753 struct mutex i_mutex;
754
755 unsigned long i_state;
756 unsigned long dirtied_when; /* jiffies of first dirtying */
757
758 struct hlist_node i_hash;
759 struct list_head i_wb_list; /* backing dev IO list */
760 struct list_head i_lru; /* inode LRU list */
761 struct list_head i_sb_list;
762 union {
763 struct list_head i_dentry;
764 struct rcu_head i_rcu;
765 };
766 unsigned long i_ino;
767 atomic_t i_count;
768 unsigned int i_nlink;
769 dev_t i_rdev;
770 unsigned int i_blkbits;
771 u64 i_version;
772 loff_t i_size;
773 #ifdef __NEED_I_SIZE_ORDERED
774 seqcount_t i_size_seqcount;
775 #endif
776 struct timespec i_atime;
777 struct timespec i_mtime;
778 struct timespec i_ctime;
779 blkcnt_t i_blocks;
780 unsigned short i_bytes;
781 struct rw_semaphore i_alloc_sem;
782 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
783 struct file_lock *i_flock;
784 struct address_space *i_mapping;
785 struct address_space i_data;
786 #ifdef CONFIG_QUOTA
787 struct dquot *i_dquot[MAXQUOTAS];
788 #endif
789 struct list_head i_devices;
790 union {
791 struct pipe_inode_info *i_pipe;
792 struct block_device *i_bdev;
793 struct cdev *i_cdev;
794 };
795
796 __u32 i_generation;
797
798 #ifdef CONFIG_FSNOTIFY
799 __u32 i_fsnotify_mask; /* all events this inode cares about */
800 struct hlist_head i_fsnotify_marks;
801 #endif
802
803 #ifdef CONFIG_IMA
804 /* protected by i_lock */
805 unsigned int i_readcount; /* struct files open RO */
806 #endif
807 atomic_t i_writecount;
808 #ifdef CONFIG_SECURITY
809 void *i_security;
810 #endif
811 #ifdef CONFIG_FS_POSIX_ACL
812 struct posix_acl *i_acl;
813 struct posix_acl *i_default_acl;
814 #endif
815 void *i_private; /* fs or device private pointer */
816 };
817
818 static inline int inode_unhashed(struct inode *inode)
819 {
820 return hlist_unhashed(&inode->i_hash);
821 }
822
823 /*
824 * inode->i_mutex nesting subclasses for the lock validator:
825 *
826 * 0: the object of the current VFS operation
827 * 1: parent
828 * 2: child/target
829 * 3: quota file
830 *
831 * The locking order between these classes is
832 * parent -> child -> normal -> xattr -> quota
833 */
834 enum inode_i_mutex_lock_class
835 {
836 I_MUTEX_NORMAL,
837 I_MUTEX_PARENT,
838 I_MUTEX_CHILD,
839 I_MUTEX_XATTR,
840 I_MUTEX_QUOTA
841 };
842
843 /*
844 * NOTE: in a 32bit arch with a preemptable kernel and
845 * an UP compile the i_size_read/write must be atomic
846 * with respect to the local cpu (unlike with preempt disabled),
847 * but they don't need to be atomic with respect to other cpus like in
848 * true SMP (so they need either to either locally disable irq around
849 * the read or for example on x86 they can be still implemented as a
850 * cmpxchg8b without the need of the lock prefix). For SMP compiles
851 * and 64bit archs it makes no difference if preempt is enabled or not.
852 */
853 static inline loff_t i_size_read(const struct inode *inode)
854 {
855 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
856 loff_t i_size;
857 unsigned int seq;
858
859 do {
860 seq = read_seqcount_begin(&inode->i_size_seqcount);
861 i_size = inode->i_size;
862 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
863 return i_size;
864 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
865 loff_t i_size;
866
867 preempt_disable();
868 i_size = inode->i_size;
869 preempt_enable();
870 return i_size;
871 #else
872 return inode->i_size;
873 #endif
874 }
875
876 /*
877 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
878 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
879 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
880 */
881 static inline void i_size_write(struct inode *inode, loff_t i_size)
882 {
883 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
884 write_seqcount_begin(&inode->i_size_seqcount);
885 inode->i_size = i_size;
886 write_seqcount_end(&inode->i_size_seqcount);
887 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
888 preempt_disable();
889 inode->i_size = i_size;
890 preempt_enable();
891 #else
892 inode->i_size = i_size;
893 #endif
894 }
895
896 static inline unsigned iminor(const struct inode *inode)
897 {
898 return MINOR(inode->i_rdev);
899 }
900
901 static inline unsigned imajor(const struct inode *inode)
902 {
903 return MAJOR(inode->i_rdev);
904 }
905
906 extern struct block_device *I_BDEV(struct inode *inode);
907
908 struct fown_struct {
909 rwlock_t lock; /* protects pid, uid, euid fields */
910 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
911 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
912 uid_t uid, euid; /* uid/euid of process setting the owner */
913 int signum; /* posix.1b rt signal to be delivered on IO */
914 };
915
916 /*
917 * Track a single file's readahead state
918 */
919 struct file_ra_state {
920 pgoff_t start; /* where readahead started */
921 unsigned int size; /* # of readahead pages */
922 unsigned int async_size; /* do asynchronous readahead when
923 there are only # of pages ahead */
924
925 unsigned int ra_pages; /* Maximum readahead window */
926 unsigned int mmap_miss; /* Cache miss stat for mmap accesses */
927 loff_t prev_pos; /* Cache last read() position */
928 };
929
930 /*
931 * Check if @index falls in the readahead windows.
932 */
933 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
934 {
935 return (index >= ra->start &&
936 index < ra->start + ra->size);
937 }
938
939 #define FILE_MNT_WRITE_TAKEN 1
940 #define FILE_MNT_WRITE_RELEASED 2
941
942 struct file {
943 /*
944 * fu_list becomes invalid after file_free is called and queued via
945 * fu_rcuhead for RCU freeing
946 */
947 union {
948 struct list_head fu_list;
949 struct rcu_head fu_rcuhead;
950 } f_u;
951 struct path f_path;
952 #define f_dentry f_path.dentry
953 #define f_vfsmnt f_path.mnt
954 const struct file_operations *f_op;
955 spinlock_t f_lock; /* f_ep_links, f_flags, no IRQ */
956 #ifdef CONFIG_SMP
957 int f_sb_list_cpu;
958 #endif
959 atomic_long_t f_count;
960 unsigned int f_flags;
961 fmode_t f_mode;
962 loff_t f_pos;
963 struct fown_struct f_owner;
964 const struct cred *f_cred;
965 struct file_ra_state f_ra;
966
967 u64 f_version;
968 #ifdef CONFIG_SECURITY
969 void *f_security;
970 #endif
971 /* needed for tty driver, and maybe others */
972 void *private_data;
973
974 #ifdef CONFIG_EPOLL
975 /* Used by fs/eventpoll.c to link all the hooks to this file */
976 struct list_head f_ep_links;
977 #endif /* #ifdef CONFIG_EPOLL */
978 struct address_space *f_mapping;
979 #ifdef CONFIG_DEBUG_WRITECOUNT
980 unsigned long f_mnt_write_state;
981 #endif
982 };
983
984 struct file_handle {
985 __u32 handle_bytes;
986 int handle_type;
987 /* file identifier */
988 unsigned char f_handle[0];
989 };
990
991 #define get_file(x) atomic_long_inc(&(x)->f_count)
992 #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1)
993 #define file_count(x) atomic_long_read(&(x)->f_count)
994
995 #ifdef CONFIG_DEBUG_WRITECOUNT
996 static inline void file_take_write(struct file *f)
997 {
998 WARN_ON(f->f_mnt_write_state != 0);
999 f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN;
1000 }
1001 static inline void file_release_write(struct file *f)
1002 {
1003 f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED;
1004 }
1005 static inline void file_reset_write(struct file *f)
1006 {
1007 f->f_mnt_write_state = 0;
1008 }
1009 static inline void file_check_state(struct file *f)
1010 {
1011 /*
1012 * At this point, either both or neither of these bits
1013 * should be set.
1014 */
1015 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN);
1016 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED);
1017 }
1018 static inline int file_check_writeable(struct file *f)
1019 {
1020 if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN)
1021 return 0;
1022 printk(KERN_WARNING "writeable file with no "
1023 "mnt_want_write()\n");
1024 WARN_ON(1);
1025 return -EINVAL;
1026 }
1027 #else /* !CONFIG_DEBUG_WRITECOUNT */
1028 static inline void file_take_write(struct file *filp) {}
1029 static inline void file_release_write(struct file *filp) {}
1030 static inline void file_reset_write(struct file *filp) {}
1031 static inline void file_check_state(struct file *filp) {}
1032 static inline int file_check_writeable(struct file *filp)
1033 {
1034 return 0;
1035 }
1036 #endif /* CONFIG_DEBUG_WRITECOUNT */
1037
1038 #define MAX_NON_LFS ((1UL<<31) - 1)
1039
1040 /* Page cache limit. The filesystems should put that into their s_maxbytes
1041 limits, otherwise bad things can happen in VM. */
1042 #if BITS_PER_LONG==32
1043 #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
1044 #elif BITS_PER_LONG==64
1045 #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
1046 #endif
1047
1048 #define FL_POSIX 1
1049 #define FL_FLOCK 2
1050 #define FL_ACCESS 8 /* not trying to lock, just looking */
1051 #define FL_EXISTS 16 /* when unlocking, test for existence */
1052 #define FL_LEASE 32 /* lease held on this file */
1053 #define FL_CLOSE 64 /* unlock on close */
1054 #define FL_SLEEP 128 /* A blocking lock */
1055
1056 /*
1057 * Special return value from posix_lock_file() and vfs_lock_file() for
1058 * asynchronous locking.
1059 */
1060 #define FILE_LOCK_DEFERRED 1
1061
1062 /*
1063 * The POSIX file lock owner is determined by
1064 * the "struct files_struct" in the thread group
1065 * (or NULL for no owner - BSD locks).
1066 *
1067 * Lockd stuffs a "host" pointer into this.
1068 */
1069 typedef struct files_struct *fl_owner_t;
1070
1071 struct file_lock_operations {
1072 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
1073 void (*fl_release_private)(struct file_lock *);
1074 };
1075
1076 struct lock_manager_operations {
1077 int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
1078 void (*fl_notify)(struct file_lock *); /* unblock callback */
1079 int (*fl_grant)(struct file_lock *, struct file_lock *, int);
1080 void (*fl_release_private)(struct file_lock *);
1081 void (*fl_break)(struct file_lock *);
1082 int (*fl_change)(struct file_lock **, int);
1083 };
1084
1085 struct lock_manager {
1086 struct list_head list;
1087 };
1088
1089 void locks_start_grace(struct lock_manager *);
1090 void locks_end_grace(struct lock_manager *);
1091 int locks_in_grace(void);
1092
1093 /* that will die - we need it for nfs_lock_info */
1094 #include <linux/nfs_fs_i.h>
1095
1096 struct file_lock {
1097 struct file_lock *fl_next; /* singly linked list for this inode */
1098 struct list_head fl_link; /* doubly linked list of all locks */
1099 struct list_head fl_block; /* circular list of blocked processes */
1100 fl_owner_t fl_owner;
1101 unsigned char fl_flags;
1102 unsigned char fl_type;
1103 unsigned int fl_pid;
1104 struct pid *fl_nspid;
1105 wait_queue_head_t fl_wait;
1106 struct file *fl_file;
1107 loff_t fl_start;
1108 loff_t fl_end;
1109
1110 struct fasync_struct * fl_fasync; /* for lease break notifications */
1111 unsigned long fl_break_time; /* for nonblocking lease breaks */
1112
1113 const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
1114 const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
1115 union {
1116 struct nfs_lock_info nfs_fl;
1117 struct nfs4_lock_info nfs4_fl;
1118 struct {
1119 struct list_head link; /* link in AFS vnode's pending_locks list */
1120 int state; /* state of grant or error if -ve */
1121 } afs;
1122 } fl_u;
1123 };
1124
1125 /* The following constant reflects the upper bound of the file/locking space */
1126 #ifndef OFFSET_MAX
1127 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
1128 #define OFFSET_MAX INT_LIMIT(loff_t)
1129 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
1130 #endif
1131
1132 #include <linux/fcntl.h>
1133
1134 extern void send_sigio(struct fown_struct *fown, int fd, int band);
1135
1136 #ifdef CONFIG_FILE_LOCKING
1137 extern int fcntl_getlk(struct file *, struct flock __user *);
1138 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
1139 struct flock __user *);
1140
1141 #if BITS_PER_LONG == 32
1142 extern int fcntl_getlk64(struct file *, struct flock64 __user *);
1143 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
1144 struct flock64 __user *);
1145 #endif
1146
1147 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
1148 extern int fcntl_getlease(struct file *filp);
1149
1150 /* fs/locks.c */
1151 void locks_free_lock(struct file_lock *fl);
1152 extern void locks_init_lock(struct file_lock *);
1153 extern struct file_lock * locks_alloc_lock(void);
1154 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1155 extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);
1156 extern void locks_remove_posix(struct file *, fl_owner_t);
1157 extern void locks_remove_flock(struct file *);
1158 extern void locks_release_private(struct file_lock *);
1159 extern void posix_test_lock(struct file *, struct file_lock *);
1160 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
1161 extern int posix_lock_file_wait(struct file *, struct file_lock *);
1162 extern int posix_unblock_lock(struct file *, struct file_lock *);
1163 extern int vfs_test_lock(struct file *, struct file_lock *);
1164 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
1165 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
1166 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
1167 extern int __break_lease(struct inode *inode, unsigned int flags);
1168 extern void lease_get_mtime(struct inode *, struct timespec *time);
1169 extern int generic_setlease(struct file *, long, struct file_lock **);
1170 extern int vfs_setlease(struct file *, long, struct file_lock **);
1171 extern int lease_modify(struct file_lock **, int);
1172 extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
1173 extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
1174 extern void lock_flocks(void);
1175 extern void unlock_flocks(void);
1176 #else /* !CONFIG_FILE_LOCKING */
1177 static inline int fcntl_getlk(struct file *file, struct flock __user *user)
1178 {
1179 return -EINVAL;
1180 }
1181
1182 static inline int fcntl_setlk(unsigned int fd, struct file *file,
1183 unsigned int cmd, struct flock __user *user)
1184 {
1185 return -EACCES;
1186 }
1187
1188 #if BITS_PER_LONG == 32
1189 static inline int fcntl_getlk64(struct file *file, struct flock64 __user *user)
1190 {
1191 return -EINVAL;
1192 }
1193
1194 static inline int fcntl_setlk64(unsigned int fd, struct file *file,
1195 unsigned int cmd, struct flock64 __user *user)
1196 {
1197 return -EACCES;
1198 }
1199 #endif
1200 static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
1201 {
1202 return 0;
1203 }
1204
1205 static inline int fcntl_getlease(struct file *filp)
1206 {
1207 return 0;
1208 }
1209
1210 static inline void locks_init_lock(struct file_lock *fl)
1211 {
1212 return;
1213 }
1214
1215 static inline void __locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1216 {
1217 return;
1218 }
1219
1220 static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
1221 {
1222 return;
1223 }
1224
1225 static inline void locks_remove_posix(struct file *filp, fl_owner_t owner)
1226 {
1227 return;
1228 }
1229
1230 static inline void locks_remove_flock(struct file *filp)
1231 {
1232 return;
1233 }
1234
1235 static inline void posix_test_lock(struct file *filp, struct file_lock *fl)
1236 {
1237 return;
1238 }
1239
1240 static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
1241 struct file_lock *conflock)
1242 {
1243 return -ENOLCK;
1244 }
1245
1246 static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
1247 {
1248 return -ENOLCK;
1249 }
1250
1251 static inline int posix_unblock_lock(struct file *filp,
1252 struct file_lock *waiter)
1253 {
1254 return -ENOENT;
1255 }
1256
1257 static inline int vfs_test_lock(struct file *filp, struct file_lock *fl)
1258 {
1259 return 0;
1260 }
1261
1262 static inline int vfs_lock_file(struct file *filp, unsigned int cmd,
1263 struct file_lock *fl, struct file_lock *conf)
1264 {
1265 return -ENOLCK;
1266 }
1267
1268 static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
1269 {
1270 return 0;
1271 }
1272
1273 static inline int flock_lock_file_wait(struct file *filp,
1274 struct file_lock *request)
1275 {
1276 return -ENOLCK;
1277 }
1278
1279 static inline int __break_lease(struct inode *inode, unsigned int mode)
1280 {
1281 return 0;
1282 }
1283
1284 static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
1285 {
1286 return;
1287 }
1288
1289 static inline int generic_setlease(struct file *filp, long arg,
1290 struct file_lock **flp)
1291 {
1292 return -EINVAL;
1293 }
1294
1295 static inline int vfs_setlease(struct file *filp, long arg,
1296 struct file_lock **lease)
1297 {
1298 return -EINVAL;
1299 }
1300
1301 static inline int lease_modify(struct file_lock **before, int arg)
1302 {
1303 return -EINVAL;
1304 }
1305
1306 static inline int lock_may_read(struct inode *inode, loff_t start,
1307 unsigned long len)
1308 {
1309 return 1;
1310 }
1311
1312 static inline int lock_may_write(struct inode *inode, loff_t start,
1313 unsigned long len)
1314 {
1315 return 1;
1316 }
1317
1318 static inline void lock_flocks(void)
1319 {
1320 }
1321
1322 static inline void unlock_flocks(void)
1323 {
1324 }
1325
1326 #endif /* !CONFIG_FILE_LOCKING */
1327
1328
1329 struct fasync_struct {
1330 spinlock_t fa_lock;
1331 int magic;
1332 int fa_fd;
1333 struct fasync_struct *fa_next; /* singly linked list */
1334 struct file *fa_file;
1335 struct rcu_head fa_rcu;
1336 };
1337
1338 #define FASYNC_MAGIC 0x4601
1339
1340 /* SMP safe fasync helpers: */
1341 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1342 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *);
1343 extern int fasync_remove_entry(struct file *, struct fasync_struct **);
1344 extern struct fasync_struct *fasync_alloc(void);
1345 extern void fasync_free(struct fasync_struct *);
1346
1347 /* can be called from interrupts */
1348 extern void kill_fasync(struct fasync_struct **, int, int);
1349
1350 extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1351 extern int f_setown(struct file *filp, unsigned long arg, int force);
1352 extern void f_delown(struct file *filp);
1353 extern pid_t f_getown(struct file *filp);
1354 extern int send_sigurg(struct fown_struct *fown);
1355
1356 /*
1357 * Umount options
1358 */
1359
1360 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1361 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1362 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1363 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
1364 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
1365
1366 extern struct list_head super_blocks;
1367 extern spinlock_t sb_lock;
1368
1369 struct super_block {
1370 struct list_head s_list; /* Keep this first */
1371 dev_t s_dev; /* search index; _not_ kdev_t */
1372 unsigned char s_dirt;
1373 unsigned char s_blocksize_bits;
1374 unsigned long s_blocksize;
1375 loff_t s_maxbytes; /* Max file size */
1376 struct file_system_type *s_type;
1377 const struct super_operations *s_op;
1378 const struct dquot_operations *dq_op;
1379 const struct quotactl_ops *s_qcop;
1380 const struct export_operations *s_export_op;
1381 unsigned long s_flags;
1382 unsigned long s_magic;
1383 struct dentry *s_root;
1384 struct rw_semaphore s_umount;
1385 struct mutex s_lock;
1386 int s_count;
1387 atomic_t s_active;
1388 #ifdef CONFIG_SECURITY
1389 void *s_security;
1390 #endif
1391 const struct xattr_handler **s_xattr;
1392
1393 struct list_head s_inodes; /* all inodes */
1394 struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
1395 #ifdef CONFIG_SMP
1396 struct list_head __percpu *s_files;
1397 #else
1398 struct list_head s_files;
1399 #endif
1400 /* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */
1401 struct list_head s_dentry_lru; /* unused dentry lru */
1402 int s_nr_dentry_unused; /* # of dentry on lru */
1403
1404 struct block_device *s_bdev;
1405 struct backing_dev_info *s_bdi;
1406 struct mtd_info *s_mtd;
1407 struct list_head s_instances;
1408 struct quota_info s_dquot; /* Diskquota specific options */
1409
1410 int s_frozen;
1411 wait_queue_head_t s_wait_unfrozen;
1412
1413 char s_id[32]; /* Informational name */
1414 u8 s_uuid[16]; /* UUID */
1415
1416 void *s_fs_info; /* Filesystem private info */
1417 fmode_t s_mode;
1418
1419 /* Granularity of c/m/atime in ns.
1420 Cannot be worse than a second */
1421 u32 s_time_gran;
1422
1423 /*
1424 * The next field is for VFS *only*. No filesystems have any business
1425 * even looking at it. You had been warned.
1426 */
1427 struct mutex s_vfs_rename_mutex; /* Kludge */
1428
1429 /*
1430 * Filesystem subtype. If non-empty the filesystem type field
1431 * in /proc/mounts will be "type.subtype"
1432 */
1433 char *s_subtype;
1434
1435 /*
1436 * Saved mount options for lazy filesystems using
1437 * generic_show_options()
1438 */
1439 char __rcu *s_options;
1440 const struct dentry_operations *s_d_op; /* default d_op for dentries */
1441 };
1442
1443 extern struct timespec current_fs_time(struct super_block *sb);
1444
1445 /*
1446 * Snapshotting support.
1447 */
1448 enum {
1449 SB_UNFROZEN = 0,
1450 SB_FREEZE_WRITE = 1,
1451 SB_FREEZE_TRANS = 2,
1452 };
1453
1454 #define vfs_check_frozen(sb, level) \
1455 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
1456
1457 #define get_fs_excl() atomic_inc(&current->fs_excl)
1458 #define put_fs_excl() atomic_dec(&current->fs_excl)
1459 #define has_fs_excl() atomic_read(&current->fs_excl)
1460
1461 #define is_owner_or_cap(inode) \
1462 ((current_fsuid() == (inode)->i_uid) || capable(CAP_FOWNER))
1463
1464 /* not quite ready to be deprecated, but... */
1465 extern void lock_super(struct super_block *);
1466 extern void unlock_super(struct super_block *);
1467
1468 /*
1469 * VFS helper functions..
1470 */
1471 extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
1472 extern int vfs_mkdir(struct inode *, struct dentry *, int);
1473 extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
1474 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
1475 extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
1476 extern int vfs_rmdir(struct inode *, struct dentry *);
1477 extern int vfs_unlink(struct inode *, struct dentry *);
1478 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1479
1480 /*
1481 * VFS dentry helper functions.
1482 */
1483 extern void dentry_unhash(struct dentry *dentry);
1484
1485 /*
1486 * VFS file helper functions.
1487 */
1488 extern int file_permission(struct file *, int);
1489 extern void inode_init_owner(struct inode *inode, const struct inode *dir,
1490 mode_t mode);
1491 /*
1492 * VFS FS_IOC_FIEMAP helper definitions.
1493 */
1494 struct fiemap_extent_info {
1495 unsigned int fi_flags; /* Flags as passed from user */
1496 unsigned int fi_extents_mapped; /* Number of mapped extents */
1497 unsigned int fi_extents_max; /* Size of fiemap_extent array */
1498 struct fiemap_extent __user *fi_extents_start; /* Start of
1499 fiemap_extent array */
1500 };
1501 int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
1502 u64 phys, u64 len, u32 flags);
1503 int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
1504
1505 /*
1506 * File types
1507 *
1508 * NOTE! These match bits 12..15 of stat.st_mode
1509 * (ie "(i_mode >> 12) & 15").
1510 */
1511 #define DT_UNKNOWN 0
1512 #define DT_FIFO 1
1513 #define DT_CHR 2
1514 #define DT_DIR 4
1515 #define DT_BLK 6
1516 #define DT_REG 8
1517 #define DT_LNK 10
1518 #define DT_SOCK 12
1519 #define DT_WHT 14
1520
1521 /*
1522 * This is the "filldir" function type, used by readdir() to let
1523 * the kernel specify what kind of dirent layout it wants to have.
1524 * This allows the kernel to read directories into kernel space or
1525 * to have different dirent layouts depending on the binary type.
1526 */
1527 typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
1528 struct block_device_operations;
1529
1530 /* These macros are for out of kernel modules to test that
1531 * the kernel supports the unlocked_ioctl and compat_ioctl
1532 * fields in struct file_operations. */
1533 #define HAVE_COMPAT_IOCTL 1
1534 #define HAVE_UNLOCKED_IOCTL 1
1535
1536 /*
1537 * NOTE:
1538 * all file operations except setlease can be called without
1539 * the big kernel lock held in all filesystems.
1540 */
1541 struct file_operations {
1542 struct module *owner;
1543 loff_t (*llseek) (struct file *, loff_t, int);
1544 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1545 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1546 ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1547 ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1548 int (*readdir) (struct file *, void *, filldir_t);
1549 unsigned int (*poll) (struct file *, struct poll_table_struct *);
1550 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1551 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1552 int (*mmap) (struct file *, struct vm_area_struct *);
1553 int (*open) (struct inode *, struct file *);
1554 int (*flush) (struct file *, fl_owner_t id);
1555 int (*release) (struct inode *, struct file *);
1556 int (*fsync) (struct file *, int datasync);
1557 int (*aio_fsync) (struct kiocb *, int datasync);
1558 int (*fasync) (int, struct file *, int);
1559 int (*lock) (struct file *, int, struct file_lock *);
1560 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1561 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1562 int (*check_flags)(int);
1563 int (*flock) (struct file *, int, struct file_lock *);
1564 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1565 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1566 int (*setlease)(struct file *, long, struct file_lock **);
1567 long (*fallocate)(struct file *file, int mode, loff_t offset,
1568 loff_t len);
1569 };
1570
1571 #define IPERM_FLAG_RCU 0x0001
1572
1573 struct inode_operations {
1574 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
1575 void * (*follow_link) (struct dentry *, struct nameidata *);
1576 int (*permission) (struct inode *, int, unsigned int);
1577 int (*check_acl)(struct inode *, int, unsigned int);
1578
1579 int (*readlink) (struct dentry *, char __user *,int);
1580 void (*put_link) (struct dentry *, struct nameidata *, void *);
1581
1582 int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
1583 int (*link) (struct dentry *,struct inode *,struct dentry *);
1584 int (*unlink) (struct inode *,struct dentry *);
1585 int (*symlink) (struct inode *,struct dentry *,const char *);
1586 int (*mkdir) (struct inode *,struct dentry *,int);
1587 int (*rmdir) (struct inode *,struct dentry *);
1588 int (*mknod) (struct inode *,struct dentry *,int,dev_t);
1589 int (*rename) (struct inode *, struct dentry *,
1590 struct inode *, struct dentry *);
1591 void (*truncate) (struct inode *);
1592 int (*setattr) (struct dentry *, struct iattr *);
1593 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1594 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
1595 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1596 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1597 int (*removexattr) (struct dentry *, const char *);
1598 void (*truncate_range)(struct inode *, loff_t, loff_t);
1599 int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
1600 u64 len);
1601 } ____cacheline_aligned;
1602
1603 struct seq_file;
1604
1605 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1606 unsigned long nr_segs, unsigned long fast_segs,
1607 struct iovec *fast_pointer,
1608 struct iovec **ret_pointer);
1609
1610 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1611 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1612 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1613 unsigned long, loff_t *);
1614 extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1615 unsigned long, loff_t *);
1616
1617 struct super_operations {
1618 struct inode *(*alloc_inode)(struct super_block *sb);
1619 void (*destroy_inode)(struct inode *);
1620
1621 void (*dirty_inode) (struct inode *);
1622 int (*write_inode) (struct inode *, struct writeback_control *wbc);
1623 int (*drop_inode) (struct inode *);
1624 void (*evict_inode) (struct inode *);
1625 void (*put_super) (struct super_block *);
1626 void (*write_super) (struct super_block *);
1627 int (*sync_fs)(struct super_block *sb, int wait);
1628 int (*freeze_fs) (struct super_block *);
1629 int (*unfreeze_fs) (struct super_block *);
1630 int (*statfs) (struct dentry *, struct kstatfs *);
1631 int (*remount_fs) (struct super_block *, int *, char *);
1632 void (*umount_begin) (struct super_block *);
1633
1634 int (*show_options)(struct seq_file *, struct vfsmount *);
1635 int (*show_stats)(struct seq_file *, struct vfsmount *);
1636 #ifdef CONFIG_QUOTA
1637 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1638 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1639 #endif
1640 int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
1641 };
1642
1643 /*
1644 * Inode state bits. Protected by inode_lock.
1645 *
1646 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
1647 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
1648 *
1649 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
1650 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
1651 * various stages of removing an inode.
1652 *
1653 * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
1654 *
1655 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
1656 * fdatasync(). i_atime is the usual cause.
1657 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
1658 * these changes separately from I_DIRTY_SYNC so that we
1659 * don't have to write inode on fdatasync() when only
1660 * mtime has changed in it.
1661 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
1662 * I_NEW Serves as both a mutex and completion notification.
1663 * New inodes set I_NEW. If two processes both create
1664 * the same inode, one of them will release its inode and
1665 * wait for I_NEW to be released before returning.
1666 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
1667 * also cause waiting on I_NEW, without I_NEW actually
1668 * being set. find_inode() uses this to prevent returning
1669 * nearly-dead inodes.
1670 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
1671 * is zero. I_FREEING must be set when I_WILL_FREE is
1672 * cleared.
1673 * I_FREEING Set when inode is about to be freed but still has dirty
1674 * pages or buffers attached or the inode itself is still
1675 * dirty.
1676 * I_CLEAR Added by end_writeback(). In this state the inode is clean
1677 * and can be destroyed. Inode keeps I_FREEING.
1678 *
1679 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
1680 * prohibited for many purposes. iget() must wait for
1681 * the inode to be completely released, then create it
1682 * anew. Other functions will just ignore such inodes,
1683 * if appropriate. I_NEW is used for waiting.
1684 *
1685 * I_SYNC Synchonized write of dirty inode data. The bits is
1686 * set during data writeback, and cleared with a wakeup
1687 * on the bit address once it is done.
1688 *
1689 * Q: What is the difference between I_WILL_FREE and I_FREEING?
1690 */
1691 #define I_DIRTY_SYNC (1 << 0)
1692 #define I_DIRTY_DATASYNC (1 << 1)
1693 #define I_DIRTY_PAGES (1 << 2)
1694 #define __I_NEW 3
1695 #define I_NEW (1 << __I_NEW)
1696 #define I_WILL_FREE (1 << 4)
1697 #define I_FREEING (1 << 5)
1698 #define I_CLEAR (1 << 6)
1699 #define __I_SYNC 7
1700 #define I_SYNC (1 << __I_SYNC)
1701 #define I_REFERENCED (1 << 8)
1702
1703 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1704
1705 extern void __mark_inode_dirty(struct inode *, int);
1706 static inline void mark_inode_dirty(struct inode *inode)
1707 {
1708 __mark_inode_dirty(inode, I_DIRTY);
1709 }
1710
1711 static inline void mark_inode_dirty_sync(struct inode *inode)
1712 {
1713 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1714 }
1715
1716 /**
1717 * inc_nlink - directly increment an inode's link count
1718 * @inode: inode
1719 *
1720 * This is a low-level filesystem helper to replace any
1721 * direct filesystem manipulation of i_nlink. Currently,
1722 * it is only here for parity with dec_nlink().
1723 */
1724 static inline void inc_nlink(struct inode *inode)
1725 {
1726 inode->i_nlink++;
1727 }
1728
1729 static inline void inode_inc_link_count(struct inode *inode)
1730 {
1731 inc_nlink(inode);
1732 mark_inode_dirty(inode);
1733 }
1734
1735 /**
1736 * drop_nlink - directly drop an inode's link count
1737 * @inode: inode
1738 *
1739 * This is a low-level filesystem helper to replace any
1740 * direct filesystem manipulation of i_nlink. In cases
1741 * where we are attempting to track writes to the
1742 * filesystem, a decrement to zero means an imminent
1743 * write when the file is truncated and actually unlinked
1744 * on the filesystem.
1745 */
1746 static inline void drop_nlink(struct inode *inode)
1747 {
1748 inode->i_nlink--;
1749 }
1750
1751 /**
1752 * clear_nlink - directly zero an inode's link count
1753 * @inode: inode
1754 *
1755 * This is a low-level filesystem helper to replace any
1756 * direct filesystem manipulation of i_nlink. See
1757 * drop_nlink() for why we care about i_nlink hitting zero.
1758 */
1759 static inline void clear_nlink(struct inode *inode)
1760 {
1761 inode->i_nlink = 0;
1762 }
1763
1764 static inline void inode_dec_link_count(struct inode *inode)
1765 {
1766 drop_nlink(inode);
1767 mark_inode_dirty(inode);
1768 }
1769
1770 /**
1771 * inode_inc_iversion - increments i_version
1772 * @inode: inode that need to be updated
1773 *
1774 * Every time the inode is modified, the i_version field will be incremented.
1775 * The filesystem has to be mounted with i_version flag
1776 */
1777
1778 static inline void inode_inc_iversion(struct inode *inode)
1779 {
1780 spin_lock(&inode->i_lock);
1781 inode->i_version++;
1782 spin_unlock(&inode->i_lock);
1783 }
1784
1785 extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
1786 static inline void file_accessed(struct file *file)
1787 {
1788 if (!(file->f_flags & O_NOATIME))
1789 touch_atime(file->f_path.mnt, file->f_path.dentry);
1790 }
1791
1792 int sync_inode(struct inode *inode, struct writeback_control *wbc);
1793 int sync_inode_metadata(struct inode *inode, int wait);
1794
1795 struct file_system_type {
1796 const char *name;
1797 int fs_flags;
1798 int (*get_sb) (struct file_system_type *, int,
1799 const char *, void *, struct vfsmount *);
1800 struct dentry *(*mount) (struct file_system_type *, int,
1801 const char *, void *);
1802 void (*kill_sb) (struct super_block *);
1803 struct module *owner;
1804 struct file_system_type * next;
1805 struct list_head fs_supers;
1806
1807 struct lock_class_key s_lock_key;
1808 struct lock_class_key s_umount_key;
1809 struct lock_class_key s_vfs_rename_key;
1810
1811 struct lock_class_key i_lock_key;
1812 struct lock_class_key i_mutex_key;
1813 struct lock_class_key i_mutex_dir_key;
1814 struct lock_class_key i_alloc_sem_key;
1815 };
1816
1817 extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags,
1818 void *data, int (*fill_super)(struct super_block *, void *, int));
1819 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
1820 int flags, const char *dev_name, void *data,
1821 int (*fill_super)(struct super_block *, void *, int));
1822 extern int get_sb_bdev(struct file_system_type *fs_type,
1823 int flags, const char *dev_name, void *data,
1824 int (*fill_super)(struct super_block *, void *, int),
1825 struct vfsmount *mnt);
1826 extern struct dentry *mount_single(struct file_system_type *fs_type,
1827 int flags, void *data,
1828 int (*fill_super)(struct super_block *, void *, int));
1829 extern int get_sb_single(struct file_system_type *fs_type,
1830 int flags, void *data,
1831 int (*fill_super)(struct super_block *, void *, int),
1832 struct vfsmount *mnt);
1833 extern struct dentry *mount_nodev(struct file_system_type *fs_type,
1834 int flags, void *data,
1835 int (*fill_super)(struct super_block *, void *, int));
1836 extern int get_sb_nodev(struct file_system_type *fs_type,
1837 int flags, void *data,
1838 int (*fill_super)(struct super_block *, void *, int),
1839 struct vfsmount *mnt);
1840 void generic_shutdown_super(struct super_block *sb);
1841 void kill_block_super(struct super_block *sb);
1842 void kill_anon_super(struct super_block *sb);
1843 void kill_litter_super(struct super_block *sb);
1844 void deactivate_super(struct super_block *sb);
1845 void deactivate_locked_super(struct super_block *sb);
1846 int set_anon_super(struct super_block *s, void *data);
1847 struct super_block *sget(struct file_system_type *type,
1848 int (*test)(struct super_block *,void *),
1849 int (*set)(struct super_block *,void *),
1850 void *data);
1851 extern struct dentry *mount_pseudo(struct file_system_type *, char *,
1852 const struct super_operations *ops,
1853 const struct dentry_operations *dops,
1854 unsigned long);
1855 extern void simple_set_mnt(struct vfsmount *mnt, struct super_block *sb);
1856
1857 static inline void sb_mark_dirty(struct super_block *sb)
1858 {
1859 sb->s_dirt = 1;
1860 }
1861 static inline void sb_mark_clean(struct super_block *sb)
1862 {
1863 sb->s_dirt = 0;
1864 }
1865 static inline int sb_is_dirty(struct super_block *sb)
1866 {
1867 return sb->s_dirt;
1868 }
1869
1870 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1871 #define fops_get(fops) \
1872 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1873 #define fops_put(fops) \
1874 do { if (fops) module_put((fops)->owner); } while(0)
1875
1876 extern int register_filesystem(struct file_system_type *);
1877 extern int unregister_filesystem(struct file_system_type *);
1878 extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
1879 #define kern_mount(type) kern_mount_data(type, NULL)
1880 extern int may_umount_tree(struct vfsmount *);
1881 extern int may_umount(struct vfsmount *);
1882 extern long do_mount(char *, char *, char *, unsigned long, void *);
1883 extern struct vfsmount *collect_mounts(struct path *);
1884 extern void drop_collected_mounts(struct vfsmount *);
1885 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
1886 struct vfsmount *);
1887 extern int vfs_statfs(struct path *, struct kstatfs *);
1888 extern int user_statfs(const char __user *, struct kstatfs *);
1889 extern int fd_statfs(int, struct kstatfs *);
1890 extern int statfs_by_dentry(struct dentry *, struct kstatfs *);
1891 extern int freeze_super(struct super_block *super);
1892 extern int thaw_super(struct super_block *super);
1893
1894 extern int current_umask(void);
1895
1896 /* /sys/fs */
1897 extern struct kobject *fs_kobj;
1898
1899 #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
1900 extern int rw_verify_area(int, struct file *, loff_t *, size_t);
1901
1902 #define FLOCK_VERIFY_READ 1
1903 #define FLOCK_VERIFY_WRITE 2
1904
1905 #ifdef CONFIG_FILE_LOCKING
1906 extern int locks_mandatory_locked(struct inode *);
1907 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1908
1909 /*
1910 * Candidates for mandatory locking have the setgid bit set
1911 * but no group execute bit - an otherwise meaningless combination.
1912 */
1913
1914 static inline int __mandatory_lock(struct inode *ino)
1915 {
1916 return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
1917 }
1918
1919 /*
1920 * ... and these candidates should be on MS_MANDLOCK mounted fs,
1921 * otherwise these will be advisory locks
1922 */
1923
1924 static inline int mandatory_lock(struct inode *ino)
1925 {
1926 return IS_MANDLOCK(ino) && __mandatory_lock(ino);
1927 }
1928
1929 static inline int locks_verify_locked(struct inode *inode)
1930 {
1931 if (mandatory_lock(inode))
1932 return locks_mandatory_locked(inode);
1933 return 0;
1934 }
1935
1936 static inline int locks_verify_truncate(struct inode *inode,
1937 struct file *filp,
1938 loff_t size)
1939 {
1940 if (inode->i_flock && mandatory_lock(inode))
1941 return locks_mandatory_area(
1942 FLOCK_VERIFY_WRITE, inode, filp,
1943 size < inode->i_size ? size : inode->i_size,
1944 (size < inode->i_size ? inode->i_size - size
1945 : size - inode->i_size)
1946 );
1947 return 0;
1948 }
1949
1950 static inline int break_lease(struct inode *inode, unsigned int mode)
1951 {
1952 if (inode->i_flock)
1953 return __break_lease(inode, mode);
1954 return 0;
1955 }
1956 #else /* !CONFIG_FILE_LOCKING */
1957 static inline int locks_mandatory_locked(struct inode *inode)
1958 {
1959 return 0;
1960 }
1961
1962 static inline int locks_mandatory_area(int rw, struct inode *inode,
1963 struct file *filp, loff_t offset,
1964 size_t count)
1965 {
1966 return 0;
1967 }
1968
1969 static inline int __mandatory_lock(struct inode *inode)
1970 {
1971 return 0;
1972 }
1973
1974 static inline int mandatory_lock(struct inode *inode)
1975 {
1976 return 0;
1977 }
1978
1979 static inline int locks_verify_locked(struct inode *inode)
1980 {
1981 return 0;
1982 }
1983
1984 static inline int locks_verify_truncate(struct inode *inode, struct file *filp,
1985 size_t size)
1986 {
1987 return 0;
1988 }
1989
1990 static inline int break_lease(struct inode *inode, unsigned int mode)
1991 {
1992 return 0;
1993 }
1994
1995 #endif /* CONFIG_FILE_LOCKING */
1996
1997 /* fs/open.c */
1998
1999 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
2000 struct file *filp);
2001 extern int do_fallocate(struct file *file, int mode, loff_t offset,
2002 loff_t len);
2003 extern long do_sys_open(int dfd, const char __user *filename, int flags,
2004 int mode);
2005 extern struct file *filp_open(const char *, int, int);
2006 extern struct file *file_open_root(struct dentry *, struct vfsmount *,
2007 const char *, int);
2008 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int,
2009 const struct cred *);
2010 extern int filp_close(struct file *, fl_owner_t id);
2011 extern char * getname(const char __user *);
2012
2013 /* fs/ioctl.c */
2014
2015 extern int ioctl_preallocate(struct file *filp, void __user *argp);
2016
2017 /* fs/dcache.c */
2018 extern void __init vfs_caches_init_early(void);
2019 extern void __init vfs_caches_init(unsigned long);
2020
2021 extern struct kmem_cache *names_cachep;
2022
2023 #define __getname_gfp(gfp) kmem_cache_alloc(names_cachep, (gfp))
2024 #define __getname() __getname_gfp(GFP_KERNEL)
2025 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
2026 #ifndef CONFIG_AUDITSYSCALL
2027 #define putname(name) __putname(name)
2028 #else
2029 extern void putname(const char *name);
2030 #endif
2031
2032 #ifdef CONFIG_BLOCK
2033 extern int register_blkdev(unsigned int, const char *);
2034 extern void unregister_blkdev(unsigned int, const char *);
2035 extern struct block_device *bdget(dev_t);
2036 extern struct block_device *bdgrab(struct block_device *bdev);
2037 extern void bd_set_size(struct block_device *, loff_t size);
2038 extern void bd_forget(struct inode *inode);
2039 extern void bdput(struct block_device *);
2040 extern void invalidate_bdev(struct block_device *);
2041 extern int sync_blockdev(struct block_device *bdev);
2042 extern struct super_block *freeze_bdev(struct block_device *);
2043 extern void emergency_thaw_all(void);
2044 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
2045 extern int fsync_bdev(struct block_device *);
2046 #else
2047 static inline void bd_forget(struct inode *inode) {}
2048 static inline int sync_blockdev(struct block_device *bdev) { return 0; }
2049 static inline void invalidate_bdev(struct block_device *bdev) {}
2050
2051 static inline struct super_block *freeze_bdev(struct block_device *sb)
2052 {
2053 return NULL;
2054 }
2055
2056 static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
2057 {
2058 return 0;
2059 }
2060 #endif
2061 extern int sync_filesystem(struct super_block *);
2062 extern const struct file_operations def_blk_fops;
2063 extern const struct file_operations def_chr_fops;
2064 extern const struct file_operations bad_sock_fops;
2065 extern const struct file_operations def_fifo_fops;
2066 #ifdef CONFIG_BLOCK
2067 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
2068 extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
2069 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
2070 extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
2071 extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
2072 void *holder);
2073 extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
2074 void *holder);
2075 extern int blkdev_put(struct block_device *bdev, fmode_t mode);
2076 #ifdef CONFIG_SYSFS
2077 extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
2078 extern void bd_unlink_disk_holder(struct block_device *bdev,
2079 struct gendisk *disk);
2080 #else
2081 static inline int bd_link_disk_holder(struct block_device *bdev,
2082 struct gendisk *disk)
2083 {
2084 return 0;
2085 }
2086 static inline void bd_unlink_disk_holder(struct block_device *bdev,
2087 struct gendisk *disk)
2088 {
2089 }
2090 #endif
2091 #endif
2092
2093 /* fs/char_dev.c */
2094 #define CHRDEV_MAJOR_HASH_SIZE 255
2095 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
2096 extern int register_chrdev_region(dev_t, unsigned, const char *);
2097 extern int __register_chrdev(unsigned int major, unsigned int baseminor,
2098 unsigned int count, const char *name,
2099 const struct file_operations *fops);
2100 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor,
2101 unsigned int count, const char *name);
2102 extern void unregister_chrdev_region(dev_t, unsigned);
2103 extern void chrdev_show(struct seq_file *,off_t);
2104
2105 static inline int register_chrdev(unsigned int major, const char *name,
2106 const struct file_operations *fops)
2107 {
2108 return __register_chrdev(major, 0, 256, name, fops);
2109 }
2110
2111 static inline void unregister_chrdev(unsigned int major, const char *name)
2112 {
2113 __unregister_chrdev(major, 0, 256, name);
2114 }
2115
2116 /* fs/block_dev.c */
2117 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
2118 #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
2119
2120 #ifdef CONFIG_BLOCK
2121 #define BLKDEV_MAJOR_HASH_SIZE 255
2122 extern const char *__bdevname(dev_t, char *buffer);
2123 extern const char *bdevname(struct block_device *bdev, char *buffer);
2124 extern struct block_device *lookup_bdev(const char *);
2125 extern void blkdev_show(struct seq_file *,off_t);
2126
2127 #else
2128 #define BLKDEV_MAJOR_HASH_SIZE 0
2129 #endif
2130
2131 extern void init_special_inode(struct inode *, umode_t, dev_t);
2132
2133 /* Invalid inode operations -- fs/bad_inode.c */
2134 extern void make_bad_inode(struct inode *);
2135 extern int is_bad_inode(struct inode *);
2136
2137 extern const struct file_operations read_pipefifo_fops;
2138 extern const struct file_operations write_pipefifo_fops;
2139 extern const struct file_operations rdwr_pipefifo_fops;
2140
2141 extern int fs_may_remount_ro(struct super_block *);
2142
2143 #ifdef CONFIG_BLOCK
2144 /*
2145 * return READ, READA, or WRITE
2146 */
2147 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
2148
2149 /*
2150 * return data direction, READ or WRITE
2151 */
2152 #define bio_data_dir(bio) ((bio)->bi_rw & 1)
2153
2154 extern void check_disk_size_change(struct gendisk *disk,
2155 struct block_device *bdev);
2156 extern int revalidate_disk(struct gendisk *);
2157 extern int check_disk_change(struct block_device *);
2158 extern int __invalidate_device(struct block_device *, bool);
2159 extern int invalidate_partition(struct gendisk *, int);
2160 #endif
2161 unsigned long invalidate_mapping_pages(struct address_space *mapping,
2162 pgoff_t start, pgoff_t end);
2163
2164 static inline void invalidate_remote_inode(struct inode *inode)
2165 {
2166 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2167 S_ISLNK(inode->i_mode))
2168 invalidate_mapping_pages(inode->i_mapping, 0, -1);
2169 }
2170 extern int invalidate_inode_pages2(struct address_space *mapping);
2171 extern int invalidate_inode_pages2_range(struct address_space *mapping,
2172 pgoff_t start, pgoff_t end);
2173 extern int write_inode_now(struct inode *, int);
2174 extern int filemap_fdatawrite(struct address_space *);
2175 extern int filemap_flush(struct address_space *);
2176 extern int filemap_fdatawait(struct address_space *);
2177 extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
2178 loff_t lend);
2179 extern int filemap_write_and_wait(struct address_space *mapping);
2180 extern int filemap_write_and_wait_range(struct address_space *mapping,
2181 loff_t lstart, loff_t lend);
2182 extern int __filemap_fdatawrite_range(struct address_space *mapping,
2183 loff_t start, loff_t end, int sync_mode);
2184 extern int filemap_fdatawrite_range(struct address_space *mapping,
2185 loff_t start, loff_t end);
2186
2187 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
2188 int datasync);
2189 extern int vfs_fsync(struct file *file, int datasync);
2190 extern int generic_write_sync(struct file *file, loff_t pos, loff_t count);
2191 extern void sync_supers(void);
2192 extern void emergency_sync(void);
2193 extern void emergency_remount(void);
2194 #ifdef CONFIG_BLOCK
2195 extern sector_t bmap(struct inode *, sector_t);
2196 #endif
2197 extern int notify_change(struct dentry *, struct iattr *);
2198 extern int inode_permission(struct inode *, int);
2199 extern int generic_permission(struct inode *, int, unsigned int,
2200 int (*check_acl)(struct inode *, int, unsigned int));
2201
2202 static inline bool execute_ok(struct inode *inode)
2203 {
2204 return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
2205 }
2206
2207 extern int get_write_access(struct inode *);
2208 extern int deny_write_access(struct file *);
2209 static inline void put_write_access(struct inode * inode)
2210 {
2211 atomic_dec(&inode->i_writecount);
2212 }
2213 static inline void allow_write_access(struct file *file)
2214 {
2215 if (file)
2216 atomic_inc(&file->f_path.dentry->d_inode->i_writecount);
2217 }
2218 extern int do_pipe_flags(int *, int);
2219 extern struct file *create_read_pipe(struct file *f, int flags);
2220 extern struct file *create_write_pipe(int flags);
2221 extern void free_write_pipe(struct file *);
2222
2223 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
2224 extern struct file * open_exec(const char *);
2225
2226 /* fs/dcache.c -- generic fs support functions */
2227 extern int is_subdir(struct dentry *, struct dentry *);
2228 extern int path_is_under(struct path *, struct path *);
2229 extern ino_t find_inode_number(struct dentry *, struct qstr *);
2230
2231 #include <linux/err.h>
2232
2233 /* needed for stackable file system support */
2234 extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
2235
2236 extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
2237
2238 extern int inode_init_always(struct super_block *, struct inode *);
2239 extern void inode_init_once(struct inode *);
2240 extern void address_space_init_once(struct address_space *mapping);
2241 extern void ihold(struct inode * inode);
2242 extern void iput(struct inode *);
2243 extern struct inode * igrab(struct inode *);
2244 extern ino_t iunique(struct super_block *, ino_t);
2245 extern int inode_needs_sync(struct inode *inode);
2246 extern int generic_delete_inode(struct inode *inode);
2247 extern int generic_drop_inode(struct inode *inode);
2248
2249 extern struct inode *ilookup5_nowait(struct super_block *sb,
2250 unsigned long hashval, int (*test)(struct inode *, void *),
2251 void *data);
2252 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
2253 int (*test)(struct inode *, void *), void *data);
2254 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
2255
2256 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
2257 extern struct inode * iget_locked(struct super_block *, unsigned long);
2258 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *);
2259 extern int insert_inode_locked(struct inode *);
2260 extern void unlock_new_inode(struct inode *);
2261 extern unsigned int get_next_ino(void);
2262
2263 extern void __iget(struct inode * inode);
2264 extern void iget_failed(struct inode *);
2265 extern void end_writeback(struct inode *);
2266 extern void __destroy_inode(struct inode *);
2267 extern struct inode *new_inode(struct super_block *);
2268 extern void free_inode_nonrcu(struct inode *inode);
2269 extern int should_remove_suid(struct dentry *);
2270 extern int file_remove_suid(struct file *);
2271
2272 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
2273 extern void remove_inode_hash(struct inode *);
2274 static inline void insert_inode_hash(struct inode *inode)
2275 {
2276 __insert_inode_hash(inode, inode->i_ino);
2277 }
2278 extern void inode_sb_list_add(struct inode *inode);
2279
2280 #ifdef CONFIG_BLOCK
2281 extern void submit_bio(int, struct bio *);
2282 extern int bdev_read_only(struct block_device *);
2283 #endif
2284 extern int set_blocksize(struct block_device *, int);
2285 extern int sb_set_blocksize(struct super_block *, int);
2286 extern int sb_min_blocksize(struct super_block *, int);
2287
2288 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
2289 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
2290 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
2291 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
2292 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
2293 extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
2294 loff_t *);
2295 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
2296 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
2297 unsigned long *, loff_t, loff_t *, size_t, size_t);
2298 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
2299 unsigned long, loff_t, loff_t *, size_t, ssize_t);
2300 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
2301 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
2302 extern int generic_segment_checks(const struct iovec *iov,
2303 unsigned long *nr_segs, size_t *count, int access_flags);
2304
2305 /* fs/block_dev.c */
2306 extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
2307 unsigned long nr_segs, loff_t pos);
2308 extern int blkdev_fsync(struct file *filp, int datasync);
2309
2310 /* fs/splice.c */
2311 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
2312 struct pipe_inode_info *, size_t, unsigned int);
2313 extern ssize_t default_file_splice_read(struct file *, loff_t *,
2314 struct pipe_inode_info *, size_t, unsigned int);
2315 extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
2316 struct file *, loff_t *, size_t, unsigned int);
2317 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
2318 struct file *out, loff_t *, size_t len, unsigned int flags);
2319 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
2320 size_t len, unsigned int flags);
2321
2322 extern void
2323 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
2324 extern loff_t noop_llseek(struct file *file, loff_t offset, int origin);
2325 extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
2326 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
2327 extern loff_t generic_file_llseek_unlocked(struct file *file, loff_t offset,
2328 int origin);
2329 extern int generic_file_open(struct inode * inode, struct file * filp);
2330 extern int nonseekable_open(struct inode * inode, struct file * filp);
2331
2332 #ifdef CONFIG_FS_XIP
2333 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
2334 loff_t *ppos);
2335 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
2336 extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
2337 size_t len, loff_t *ppos);
2338 extern int xip_truncate_page(struct address_space *mapping, loff_t from);
2339 #else
2340 static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
2341 {
2342 return 0;
2343 }
2344 #endif
2345
2346 #ifdef CONFIG_BLOCK
2347 typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
2348 loff_t file_offset);
2349
2350 enum {
2351 /* need locking between buffered and direct access */
2352 DIO_LOCKING = 0x01,
2353
2354 /* filesystem does not support filling holes */
2355 DIO_SKIP_HOLES = 0x02,
2356 };
2357
2358 void dio_end_io(struct bio *bio, int error);
2359
2360 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
2361 struct block_device *bdev, const struct iovec *iov, loff_t offset,
2362 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
2363 dio_submit_t submit_io, int flags);
2364
2365 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
2366 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
2367 loff_t offset, unsigned long nr_segs, get_block_t get_block,
2368 dio_iodone_t end_io)
2369 {
2370 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
2371 nr_segs, get_block, end_io, NULL,
2372 DIO_LOCKING | DIO_SKIP_HOLES);
2373 }
2374 #endif
2375
2376 extern const struct file_operations generic_ro_fops;
2377
2378 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
2379
2380 extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
2381 extern int vfs_follow_link(struct nameidata *, const char *);
2382 extern int page_readlink(struct dentry *, char __user *, int);
2383 extern void *page_follow_link_light(struct dentry *, struct nameidata *);
2384 extern void page_put_link(struct dentry *, struct nameidata *, void *);
2385 extern int __page_symlink(struct inode *inode, const char *symname, int len,
2386 int nofs);
2387 extern int page_symlink(struct inode *inode, const char *symname, int len);
2388 extern const struct inode_operations page_symlink_inode_operations;
2389 extern int generic_readlink(struct dentry *, char __user *, int);
2390 extern void generic_fillattr(struct inode *, struct kstat *);
2391 extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
2392 void __inode_add_bytes(struct inode *inode, loff_t bytes);
2393 void inode_add_bytes(struct inode *inode, loff_t bytes);
2394 void inode_sub_bytes(struct inode *inode, loff_t bytes);
2395 loff_t inode_get_bytes(struct inode *inode);
2396 void inode_set_bytes(struct inode *inode, loff_t bytes);
2397
2398 extern int vfs_readdir(struct file *, filldir_t, void *);
2399
2400 extern int vfs_stat(const char __user *, struct kstat *);
2401 extern int vfs_lstat(const char __user *, struct kstat *);
2402 extern int vfs_fstat(unsigned int, struct kstat *);
2403 extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
2404
2405 extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
2406 unsigned long arg);
2407 extern int __generic_block_fiemap(struct inode *inode,
2408 struct fiemap_extent_info *fieinfo,
2409 loff_t start, loff_t len,
2410 get_block_t *get_block);
2411 extern int generic_block_fiemap(struct inode *inode,
2412 struct fiemap_extent_info *fieinfo, u64 start,
2413 u64 len, get_block_t *get_block);
2414
2415 extern void get_filesystem(struct file_system_type *fs);
2416 extern void put_filesystem(struct file_system_type *fs);
2417 extern struct file_system_type *get_fs_type(const char *name);
2418 extern struct super_block *get_super(struct block_device *);
2419 extern struct super_block *get_active_super(struct block_device *bdev);
2420 extern struct super_block *user_get_super(dev_t);
2421 extern void drop_super(struct super_block *sb);
2422 extern void iterate_supers(void (*)(struct super_block *, void *), void *);
2423
2424 extern int dcache_dir_open(struct inode *, struct file *);
2425 extern int dcache_dir_close(struct inode *, struct file *);
2426 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
2427 extern int dcache_readdir(struct file *, void *, filldir_t);
2428 extern int simple_setattr(struct dentry *, struct iattr *);
2429 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
2430 extern int simple_statfs(struct dentry *, struct kstatfs *);
2431 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
2432 extern int simple_unlink(struct inode *, struct dentry *);
2433 extern int simple_rmdir(struct inode *, struct dentry *);
2434 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
2435 extern int noop_fsync(struct file *, int);
2436 extern int simple_empty(struct dentry *);
2437 extern int simple_readpage(struct file *file, struct page *page);
2438 extern int simple_write_begin(struct file *file, struct address_space *mapping,
2439 loff_t pos, unsigned len, unsigned flags,
2440 struct page **pagep, void **fsdata);
2441 extern int simple_write_end(struct file *file, struct address_space *mapping,
2442 loff_t pos, unsigned len, unsigned copied,
2443 struct page *page, void *fsdata);
2444
2445 extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
2446 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2447 extern const struct file_operations simple_dir_operations;
2448 extern const struct inode_operations simple_dir_inode_operations;
2449 struct tree_descr { char *name; const struct file_operations *ops; int mode; };
2450 struct dentry *d_alloc_name(struct dentry *, const char *);
2451 extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
2452 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2453 extern void simple_release_fs(struct vfsmount **mount, int *count);
2454
2455 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2456 loff_t *ppos, const void *from, size_t available);
2457 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
2458 const void __user *from, size_t count);
2459
2460 extern int generic_file_fsync(struct file *, int);
2461
2462 extern int generic_check_addressable(unsigned, u64);
2463
2464 #ifdef CONFIG_MIGRATION
2465 extern int buffer_migrate_page(struct address_space *,
2466 struct page *, struct page *);
2467 #else
2468 #define buffer_migrate_page NULL
2469 #endif
2470
2471 extern int inode_change_ok(const struct inode *, struct iattr *);
2472 extern int inode_newsize_ok(const struct inode *, loff_t offset);
2473 extern void setattr_copy(struct inode *inode, const struct iattr *attr);
2474
2475 extern void file_update_time(struct file *file);
2476
2477 extern int generic_show_options(struct seq_file *m, struct vfsmount *mnt);
2478 extern void save_mount_options(struct super_block *sb, char *options);
2479 extern void replace_mount_options(struct super_block *sb, char *options);
2480
2481 static inline ino_t parent_ino(struct dentry *dentry)
2482 {
2483 ino_t res;
2484
2485 /*
2486 * Don't strictly need d_lock here? If the parent ino could change
2487 * then surely we'd have a deeper race in the caller?
2488 */
2489 spin_lock(&dentry->d_lock);
2490 res = dentry->d_parent->d_inode->i_ino;
2491 spin_unlock(&dentry->d_lock);
2492 return res;
2493 }
2494
2495 /* Transaction based IO helpers */
2496
2497 /*
2498 * An argresp is stored in an allocated page and holds the
2499 * size of the argument or response, along with its content
2500 */
2501 struct simple_transaction_argresp {
2502 ssize_t size;
2503 char data[0];
2504 };
2505
2506 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
2507
2508 char *simple_transaction_get(struct file *file, const char __user *buf,
2509 size_t size);
2510 ssize_t simple_transaction_read(struct file *file, char __user *buf,
2511 size_t size, loff_t *pos);
2512 int simple_transaction_release(struct inode *inode, struct file *file);
2513
2514 void simple_transaction_set(struct file *file, size_t n);
2515
2516 /*
2517 * simple attribute files
2518 *
2519 * These attributes behave similar to those in sysfs:
2520 *
2521 * Writing to an attribute immediately sets a value, an open file can be
2522 * written to multiple times.
2523 *
2524 * Reading from an attribute creates a buffer from the value that might get
2525 * read with multiple read calls. When the attribute has been read
2526 * completely, no further read calls are possible until the file is opened
2527 * again.
2528 *
2529 * All attributes contain a text representation of a numeric value
2530 * that are accessed with the get() and set() functions.
2531 */
2532 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
2533 static int __fops ## _open(struct inode *inode, struct file *file) \
2534 { \
2535 __simple_attr_check_format(__fmt, 0ull); \
2536 return simple_attr_open(inode, file, __get, __set, __fmt); \
2537 } \
2538 static const struct file_operations __fops = { \
2539 .owner = THIS_MODULE, \
2540 .open = __fops ## _open, \
2541 .release = simple_attr_release, \
2542 .read = simple_attr_read, \
2543 .write = simple_attr_write, \
2544 .llseek = generic_file_llseek, \
2545 };
2546
2547 static inline void __attribute__((format(printf, 1, 2)))
2548 __simple_attr_check_format(const char *fmt, ...)
2549 {
2550 /* don't do anything, just let the compiler check the arguments; */
2551 }
2552
2553 int simple_attr_open(struct inode *inode, struct file *file,
2554 int (*get)(void *, u64 *), int (*set)(void *, u64),
2555 const char *fmt);
2556 int simple_attr_release(struct inode *inode, struct file *file);
2557 ssize_t simple_attr_read(struct file *file, char __user *buf,
2558 size_t len, loff_t *ppos);
2559 ssize_t simple_attr_write(struct file *file, const char __user *buf,
2560 size_t len, loff_t *ppos);
2561
2562 struct ctl_table;
2563 int proc_nr_files(struct ctl_table *table, int write,
2564 void __user *buffer, size_t *lenp, loff_t *ppos);
2565 int proc_nr_dentry(struct ctl_table *table, int write,
2566 void __user *buffer, size_t *lenp, loff_t *ppos);
2567 int proc_nr_inodes(struct ctl_table *table, int write,
2568 void __user *buffer, size_t *lenp, loff_t *ppos);
2569 int __init get_filesystem_list(char *buf);
2570
2571 #define __FMODE_EXEC ((__force int) FMODE_EXEC)
2572 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY)
2573
2574 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
2575 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \
2576 (flag & __FMODE_NONOTIFY)))
2577
2578 #endif /* __KERNEL__ */
2579 #endif /* _LINUX_FS_H */