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