1 #ifndef _LINUX_FS_H 2 #define _LINUX_FS_H 3 4 /* 5 * This file has definitions for some important file table 6 * structures etc. 7 */ 8 9 #include <linux/limits.h> 10 #include <linux/ioctl.h> 11 #include <linux/blk_types.h> 12 #include <linux/types.h> 13 14 /* 15 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change 16 * the file limit at runtime and only root can increase the per-process 17 * nr_file rlimit, so it's safe to set up a ridiculously high absolute 18 * upper limit on files-per-process. 19 * 20 * Some programs (notably those using select()) may have to be 21 * recompiled to take full advantage of the new limits.. 22 */ 23 24 /* Fixed constants first: */ 25 #undef NR_OPEN 26 #define INR_OPEN 1024 /* Initial setting for nfile rlimits */ 27 28 #define BLOCK_SIZE_BITS 10 29 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS) 30 31 #define SEEK_SET 0 /* seek relative to beginning of file */ 32 #define SEEK_CUR 1 /* seek relative to current file position */ 33 #define SEEK_END 2 /* seek relative to end of file */ 34 #define SEEK_MAX SEEK_END 35 36 struct fstrim_range { 37 __u64 start; 38 __u64 len; 39 __u64 minlen; 40 }; 41 42 /* And dynamically-tunable limits and defaults: */ 43 struct files_stat_struct { 44 unsigned long nr_files; /* read only */ 45 unsigned long nr_free_files; /* read only */ 46 unsigned long max_files; /* tunable */ 47 }; 48 49 struct inodes_stat_t { 50 int nr_inodes; 51 int nr_unused; 52 int dummy[5]; /* padding for sysctl ABI compatibility */ 53 }; 54 55 56 #define NR_FILE 8192 /* this can well be larger on a larger system */ 57 58 #define MAY_EXEC 1 59 #define MAY_WRITE 2 60 #define MAY_READ 4 61 #define MAY_APPEND 8 62 #define MAY_ACCESS 16 63 #define MAY_OPEN 32 64 #define MAY_CHDIR 64 65 66 /* 67 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond 68 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open() 69 */ 70 71 /* file is open for reading */ 72 #define FMODE_READ ((__force fmode_t)0x1) 73 /* file is open for writing */ 74 #define FMODE_WRITE ((__force fmode_t)0x2) 75 /* file is seekable */ 76 #define FMODE_LSEEK ((__force fmode_t)0x4) 77 /* file can be accessed using pread */ 78 #define FMODE_PREAD ((__force fmode_t)0x8) 79 /* file can be accessed using pwrite */ 80 #define FMODE_PWRITE ((__force fmode_t)0x10) 81 /* File is opened for execution with sys_execve / sys_uselib */ 82 #define FMODE_EXEC ((__force fmode_t)0x20) 83 /* File is opened with O_NDELAY (only set for block devices) */ 84 #define FMODE_NDELAY ((__force fmode_t)0x40) 85 /* File is opened with O_EXCL (only set for block devices) */ 86 #define FMODE_EXCL ((__force fmode_t)0x80) 87 /* File is opened using open(.., 3, ..) and is writeable only for ioctls 88 (specialy hack for floppy.c) */ 89 #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100) 90 91 /* 92 * Don't update ctime and mtime. 93 * 94 * Currently a special hack for the XFS open_by_handle ioctl, but we'll 95 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon. 96 */ 97 #define FMODE_NOCMTIME ((__force fmode_t)0x800) 98 99 /* Expect random access pattern */ 100 #define FMODE_RANDOM ((__force fmode_t)0x1000) 101 102 /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */ 103 #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000) 104 105 /* File is opened with O_PATH; almost nothing can be done with it */ 106 #define FMODE_PATH ((__force fmode_t)0x4000) 107 108 /* File was opened by fanotify and shouldn't generate fanotify events */ 109 #define FMODE_NONOTIFY ((__force fmode_t)0x1000000) 110 111 /* 112 * The below are the various read and write types that we support. Some of 113 * them include behavioral modifiers that send information down to the 114 * block layer and IO scheduler. Terminology: 115 * 116 * The block layer uses device plugging to defer IO a little bit, in 117 * the hope that we will see more IO very shortly. This increases 118 * coalescing of adjacent IO and thus reduces the number of IOs we 119 * have to send to the device. It also allows for better queuing, 120 * if the IO isn't mergeable. If the caller is going to be waiting 121 * for the IO, then he must ensure that the device is unplugged so 122 * that the IO is dispatched to the driver. 123 * 124 * All IO is handled async in Linux. This is fine for background 125 * writes, but for reads or writes that someone waits for completion 126 * on, we want to notify the block layer and IO scheduler so that they 127 * know about it. That allows them to make better scheduling 128 * decisions. So when the below references 'sync' and 'async', it 129 * is referencing this priority hint. 130 * 131 * With that in mind, the available types are: 132 * 133 * READ A normal read operation. Device will be plugged. 134 * READ_SYNC A synchronous read. Device is not plugged, caller can 135 * immediately wait on this read without caring about 136 * unplugging. 137 * READA Used for read-ahead operations. Lower priority, and the 138 * block layer could (in theory) choose to ignore this 139 * request if it runs into resource problems. 140 * WRITE A normal async write. Device will be plugged. 141 * WRITE_SYNC_PLUG Synchronous write. Identical to WRITE, but passes down 142 * the hint that someone will be waiting on this IO 143 * shortly. The device must still be unplugged explicitly, 144 * WRITE_SYNC_PLUG does not do this as we could be 145 * submitting more writes before we actually wait on any 146 * of them. 147 * WRITE_SYNC Like WRITE_SYNC_PLUG, but also unplugs the device 148 * immediately after submission. The write equivalent 149 * of READ_SYNC. 150 * WRITE_ODIRECT_PLUG Special case write for O_DIRECT only. 151 * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush. 152 * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on 153 * non-volatile media on completion. 154 * WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded 155 * by a cache flush and data is guaranteed to be on 156 * non-volatile media on completion. 157 * 158 */ 159 #define RW_MASK REQ_WRITE 160 #define RWA_MASK REQ_RAHEAD 161 162 #define READ 0 163 #define WRITE RW_MASK 164 #define READA RWA_MASK 165 166 #define READ_SYNC (READ | REQ_SYNC | REQ_UNPLUG) 167 #define READ_META (READ | REQ_META) 168 #define WRITE_SYNC_PLUG (WRITE | REQ_SYNC | REQ_NOIDLE) 169 #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG) 170 #define WRITE_ODIRECT_PLUG (WRITE | REQ_SYNC) 171 #define WRITE_META (WRITE | REQ_META) 172 #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \ 173 REQ_FLUSH) 174 #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \ 175 REQ_FUA) 176 #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \ 177 REQ_FLUSH | REQ_FUA) 178 179 #define SEL_IN 1 180 #define SEL_OUT 2 181 #define SEL_EX 4 182 183 /* public flags for file_system_type */ 184 #define FS_REQUIRES_DEV 1 185 #define FS_BINARY_MOUNTDATA 2 186 #define FS_HAS_SUBTYPE 4 187 #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */ 188 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() 189 * during rename() internally. 190 */ 191 192 /* 193 * These are the fs-independent mount-flags: up to 32 flags are supported 194 */ 195 #define MS_RDONLY 1 /* Mount read-only */ 196 #define MS_NOSUID 2 /* Ignore suid and sgid bits */ 197 #define MS_NODEV 4 /* Disallow access to device special files */ 198 #define MS_NOEXEC 8 /* Disallow program execution */ 199 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */ 200 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */ 201 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */ 202 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */ 203 #define MS_NOATIME 1024 /* Do not update access times. */ 204 #define MS_NODIRATIME 2048 /* Do not update directory access times */ 205 #define MS_BIND 4096 206 #define MS_MOVE 8192 207 #define MS_REC 16384 208 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence. 209 MS_VERBOSE is deprecated. */ 210 #define MS_SILENT 32768 211 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */ 212 #define MS_UNBINDABLE (1<<17) /* change to unbindable */ 213 #define MS_PRIVATE (1<<18) /* change to private */ 214 #define MS_SLAVE (1<<19) /* change to slave */ 215 #define MS_SHARED (1<<20) /* change to shared */ 216 #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */ 217 #define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */ 218 #define MS_I_VERSION (1<<23) /* Update inode I_version field */ 219 #define MS_STRICTATIME (1<<24) /* Always perform atime updates */ 220 #define MS_BORN (1<<29) 221 #define MS_ACTIVE (1<<30) 222 #define MS_NOUSER (1<<31) 223 224 /* 225 * Superblock flags that can be altered by MS_REMOUNT 226 */ 227 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION) 228 229 /* 230 * Old magic mount flag and mask 231 */ 232 #define MS_MGC_VAL 0xC0ED0000 233 #define MS_MGC_MSK 0xffff0000 234 235 /* Inode flags - they have nothing to superblock flags now */ 236 237 #define S_SYNC 1 /* Writes are synced at once */ 238 #define S_NOATIME 2 /* Do not update access times */ 239 #define S_APPEND 4 /* Append-only file */ 240 #define S_IMMUTABLE 8 /* Immutable file */ 241 #define S_DEAD 16 /* removed, but still open directory */ 242 #define S_NOQUOTA 32 /* Inode is not counted to quota */ 243 #define S_DIRSYNC 64 /* Directory modifications are synchronous */ 244 #define S_NOCMTIME 128 /* Do not update file c/mtime */ 245 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */ 246 #define S_PRIVATE 512 /* Inode is fs-internal */ 247 #define S_IMA 1024 /* Inode has an associated IMA struct */ 248 #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */ 249 250 /* 251 * Note that nosuid etc flags are inode-specific: setting some file-system 252 * flags just means all the inodes inherit those flags by default. It might be 253 * possible to override it selectively if you really wanted to with some 254 * ioctl() that is not currently implemented. 255 * 256 * Exception: MS_RDONLY is always applied to the entire file system. 257 * 258 * Unfortunately, it is possible to change a filesystems flags with it mounted 259 * with files in use. This means that all of the inodes will not have their 260 * i_flags updated. Hence, i_flags no longer inherit the superblock mount 261 * flags, so these have to be checked separately. -- [email protected] 262 */ 263 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg)) 264 265 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY) 266 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \ 267 ((inode)->i_flags & S_SYNC)) 268 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \ 269 ((inode)->i_flags & (S_SYNC|S_DIRSYNC))) 270 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK) 271 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME) 272 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION) 273 274 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA) 275 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND) 276 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE) 277 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL) 278 279 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD) 280 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME) 281 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE) 282 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE) 283 #define IS_IMA(inode) ((inode)->i_flags & S_IMA) 284 #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT) 285 286 /* the read-only stuff doesn't really belong here, but any other place is 287 probably as bad and I don't want to create yet another include file. */ 288 289 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */ 290 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */ 291 #define BLKRRPART _IO(0x12,95) /* re-read partition table */ 292 #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */ 293 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */ 294 #define BLKRASET _IO(0x12,98) /* set read ahead for block device */ 295 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */ 296 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */ 297 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */ 298 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */ 299 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */ 300 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */ 301 #if 0 302 #define BLKPG _IO(0x12,105)/* See blkpg.h */ 303 304 /* Some people are morons. Do not use sizeof! */ 305 306 #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */ 307 #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */ 308 /* This was here just to show that the number is taken - 309 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */ 310 #endif 311 /* A jump here: 108-111 have been used for various private purposes. */ 312 #define BLKBSZGET _IOR(0x12,112,size_t) 313 #define BLKBSZSET _IOW(0x12,113,size_t) 314 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ 315 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup) 316 #define BLKTRACESTART _IO(0x12,116) 317 #define BLKTRACESTOP _IO(0x12,117) 318 #define BLKTRACETEARDOWN _IO(0x12,118) 319 #define BLKDISCARD _IO(0x12,119) 320 #define BLKIOMIN _IO(0x12,120) 321 #define BLKIOOPT _IO(0x12,121) 322 #define BLKALIGNOFF _IO(0x12,122) 323 #define BLKPBSZGET _IO(0x12,123) 324 #define BLKDISCARDZEROES _IO(0x12,124) 325 #define BLKSECDISCARD _IO(0x12,125) 326 327 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ 328 #define FIBMAP _IO(0x00,1) /* bmap access */ 329 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */ 330 #define FIFREEZE _IOWR('X', 119, int) /* Freeze */ 331 #define FITHAW _IOWR('X', 120, int) /* Thaw */ 332 #define FITRIM _IOWR('X', 121, struct fstrim_range) /* Trim */ 333 334 #define FS_IOC_GETFLAGS _IOR('f', 1, long) 335 #define FS_IOC_SETFLAGS _IOW('f', 2, long) 336 #define FS_IOC_GETVERSION _IOR('v', 1, long) 337 #define FS_IOC_SETVERSION _IOW('v', 2, long) 338 #define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap) 339 #define FS_IOC32_GETFLAGS _IOR('f', 1, int) 340 #define FS_IOC32_SETFLAGS _IOW('f', 2, int) 341 #define FS_IOC32_GETVERSION _IOR('v', 1, int) 342 #define FS_IOC32_SETVERSION _IOW('v', 2, int) 343 344 /* 345 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS) 346 */ 347 #define FS_SECRM_FL 0x00000001 /* Secure deletion */ 348 #define FS_UNRM_FL 0x00000002 /* Undelete */ 349 #define FS_COMPR_FL 0x00000004 /* Compress file */ 350 #define FS_SYNC_FL 0x00000008 /* Synchronous updates */ 351 #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */ 352 #define FS_APPEND_FL 0x00000020 /* writes to file may only append */ 353 #define FS_NODUMP_FL 0x00000040 /* do not dump file */ 354 #define FS_NOATIME_FL 0x00000080 /* do not update atime */ 355 /* Reserved for compression usage... */ 356 #define FS_DIRTY_FL 0x00000100 357 #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 358 #define FS_NOCOMP_FL 0x00000400 /* Don't compress */ 359 #define FS_ECOMPR_FL 0x00000800 /* Compression error */ 360 /* End compression flags --- maybe not all used */ 361 #define FS_BTREE_FL 0x00001000 /* btree format dir */ 362 #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */ 363 #define FS_IMAGIC_FL 0x00002000 /* AFS directory */ 364 #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */ 365 #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 366 #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */ 367 #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 368 #define FS_EXTENT_FL 0x00080000 /* Extents */ 369 #define FS_DIRECTIO_FL 0x00100000 /* Use direct i/o */ 370 #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 371 372 #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */ 373 #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */ 374 375 376 #define SYNC_FILE_RANGE_WAIT_BEFORE 1 377 #define SYNC_FILE_RANGE_WRITE 2 378 #define SYNC_FILE_RANGE_WAIT_AFTER 4 379 380 #ifdef __KERNEL__ 381 382 #include <linux/linkage.h> 383 #include <linux/wait.h> 384 #include <linux/types.h> 385 #include <linux/kdev_t.h> 386 #include <linux/dcache.h> 387 #include <linux/path.h> 388 #include <linux/stat.h> 389 #include <linux/cache.h> 390 #include <linux/list.h> 391 #include <linux/radix-tree.h> 392 #include <linux/prio_tree.h> 393 #include <linux/init.h> 394 #include <linux/pid.h> 395 #include <linux/mutex.h> 396 #include <linux/capability.h> 397 #include <linux/semaphore.h> 398 #include <linux/fiemap.h> 399 #include <linux/rculist_bl.h> 400 401 #include <asm/atomic.h> 402 #include <asm/byteorder.h> 403 404 struct export_operations; 405 struct hd_geometry; 406 struct iovec; 407 struct nameidata; 408 struct kiocb; 409 struct kobject; 410 struct pipe_inode_info; 411 struct poll_table_struct; 412 struct kstatfs; 413 struct vm_area_struct; 414 struct vfsmount; 415 struct cred; 416 417 extern void __init inode_init(void); 418 extern void __init inode_init_early(void); 419 extern void __init files_init(unsigned long); 420 421 extern struct files_stat_struct files_stat; 422 extern unsigned long get_max_files(void); 423 extern int sysctl_nr_open; 424 extern struct inodes_stat_t inodes_stat; 425 extern int leases_enable, lease_break_time; 426 427 struct buffer_head; 428 typedef int (get_block_t)(struct inode *inode, sector_t iblock, 429 struct buffer_head *bh_result, int create); 430 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset, 431 ssize_t bytes, void *private, int ret, 432 bool is_async); 433 434 /* 435 * Attribute flags. These should be or-ed together to figure out what 436 * has been changed! 437 */ 438 #define ATTR_MODE (1 << 0) 439 #define ATTR_UID (1 << 1) 440 #define ATTR_GID (1 << 2) 441 #define ATTR_SIZE (1 << 3) 442 #define ATTR_ATIME (1 << 4) 443 #define ATTR_MTIME (1 << 5) 444 #define ATTR_CTIME (1 << 6) 445 #define ATTR_ATIME_SET (1 << 7) 446 #define ATTR_MTIME_SET (1 << 8) 447 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */ 448 #define ATTR_ATTR_FLAG (1 << 10) 449 #define ATTR_KILL_SUID (1 << 11) 450 #define ATTR_KILL_SGID (1 << 12) 451 #define ATTR_FILE (1 << 13) 452 #define ATTR_KILL_PRIV (1 << 14) 453 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */ 454 #define ATTR_TIMES_SET (1 << 16) 455 456 /* 457 * This is the Inode Attributes structure, used for notify_change(). It 458 * uses the above definitions as flags, to know which values have changed. 459 * Also, in this manner, a Filesystem can look at only the values it cares 460 * about. Basically, these are the attributes that the VFS layer can 461 * request to change from the FS layer. 462 * 463 * Derek Atkins <[email protected]> 94-10-20 464 */ 465 struct iattr { 466 unsigned int ia_valid; 467 umode_t ia_mode; 468 uid_t ia_uid; 469 gid_t ia_gid; 470 loff_t ia_size; 471 struct timespec ia_atime; 472 struct timespec ia_mtime; 473 struct timespec ia_ctime; 474 475 /* 476 * Not an attribute, but an auxilary info for filesystems wanting to 477 * implement an ftruncate() like method. NOTE: filesystem should 478 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL). 479 */ 480 struct file *ia_file; 481 }; 482 483 /* 484 * Includes for diskquotas. 485 */ 486 #include <linux/quota.h> 487 488 /** 489 * enum positive_aop_returns - aop return codes with specific semantics 490 * 491 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has 492 * completed, that the page is still locked, and 493 * should be considered active. The VM uses this hint 494 * to return the page to the active list -- it won't 495 * be a candidate for writeback again in the near 496 * future. Other callers must be careful to unlock 497 * the page if they get this return. Returned by 498 * writepage(); 499 * 500 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has 501 * unlocked it and the page might have been truncated. 502 * The caller should back up to acquiring a new page and 503 * trying again. The aop will be taking reasonable 504 * precautions not to livelock. If the caller held a page 505 * reference, it should drop it before retrying. Returned 506 * by readpage(). 507 * 508 * address_space_operation functions return these large constants to indicate 509 * special semantics to the caller. These are much larger than the bytes in a 510 * page to allow for functions that return the number of bytes operated on in a 511 * given page. 512 */ 513 514 enum positive_aop_returns { 515 AOP_WRITEPAGE_ACTIVATE = 0x80000, 516 AOP_TRUNCATED_PAGE = 0x80001, 517 }; 518 519 #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */ 520 #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */ 521 #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct 522 * helper code (eg buffer layer) 523 * to clear GFP_FS from alloc */ 524 525 /* 526 * oh the beauties of C type declarations. 527 */ 528 struct page; 529 struct address_space; 530 struct writeback_control; 531 532 struct iov_iter { 533 const struct iovec *iov; 534 unsigned long nr_segs; 535 size_t iov_offset; 536 size_t count; 537 }; 538 539 size_t iov_iter_copy_from_user_atomic(struct page *page, 540 struct iov_iter *i, unsigned long offset, size_t bytes); 541 size_t iov_iter_copy_from_user(struct page *page, 542 struct iov_iter *i, unsigned long offset, size_t bytes); 543 void iov_iter_advance(struct iov_iter *i, size_t bytes); 544 int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes); 545 size_t iov_iter_single_seg_count(struct iov_iter *i); 546 547 static inline void iov_iter_init(struct iov_iter *i, 548 const struct iovec *iov, unsigned long nr_segs, 549 size_t count, size_t written) 550 { 551 i->iov = iov; 552 i->nr_segs = nr_segs; 553 i->iov_offset = 0; 554 i->count = count + written; 555 556 iov_iter_advance(i, written); 557 } 558 559 static inline size_t iov_iter_count(struct iov_iter *i) 560 { 561 return i->count; 562 } 563 564 /* 565 * "descriptor" for what we're up to with a read. 566 * This allows us to use the same read code yet 567 * have multiple different users of the data that 568 * we read from a file. 569 * 570 * The simplest case just copies the data to user 571 * mode. 572 */ 573 typedef struct { 574 size_t written; 575 size_t count; 576 union { 577 char __user *buf; 578 void *data; 579 } arg; 580 int error; 581 } read_descriptor_t; 582 583 typedef int (*read_actor_t)(read_descriptor_t *, struct page *, 584 unsigned long, unsigned long); 585 586 struct address_space_operations { 587 int (*writepage)(struct page *page, struct writeback_control *wbc); 588 int (*readpage)(struct file *, struct page *); 589 void (*sync_page)(struct page *); 590 591 /* Write back some dirty pages from this mapping. */ 592 int (*writepages)(struct address_space *, struct writeback_control *); 593 594 /* Set a page dirty. Return true if this dirtied it */ 595 int (*set_page_dirty)(struct page *page); 596 597 int (*readpages)(struct file *filp, struct address_space *mapping, 598 struct list_head *pages, unsigned nr_pages); 599 600 int (*write_begin)(struct file *, struct address_space *mapping, 601 loff_t pos, unsigned len, unsigned flags, 602 struct page **pagep, void **fsdata); 603 int (*write_end)(struct file *, struct address_space *mapping, 604 loff_t pos, unsigned len, unsigned copied, 605 struct page *page, void *fsdata); 606 607 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */ 608 sector_t (*bmap)(struct address_space *, sector_t); 609 void (*invalidatepage) (struct page *, unsigned long); 610 int (*releasepage) (struct page *, gfp_t); 611 void (*freepage)(struct page *); 612 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov, 613 loff_t offset, unsigned long nr_segs); 614 int (*get_xip_mem)(struct address_space *, pgoff_t, int, 615 void **, unsigned long *); 616 /* migrate the contents of a page to the specified target */ 617 int (*migratepage) (struct address_space *, 618 struct page *, struct page *); 619 int (*launder_page) (struct page *); 620 int (*is_partially_uptodate) (struct page *, read_descriptor_t *, 621 unsigned long); 622 int (*error_remove_page)(struct address_space *, struct page *); 623 }; 624 625 /* 626 * pagecache_write_begin/pagecache_write_end must be used by general code 627 * to write into the pagecache. 628 */ 629 int pagecache_write_begin(struct file *, struct address_space *mapping, 630 loff_t pos, unsigned len, unsigned flags, 631 struct page **pagep, void **fsdata); 632 633 int pagecache_write_end(struct file *, struct address_space *mapping, 634 loff_t pos, unsigned len, unsigned copied, 635 struct page *page, void *fsdata); 636 637 struct backing_dev_info; 638 struct address_space { 639 struct inode *host; /* owner: inode, block_device */ 640 struct radix_tree_root page_tree; /* radix tree of all pages */ 641 spinlock_t tree_lock; /* and lock protecting it */ 642 unsigned int i_mmap_writable;/* count VM_SHARED mappings */ 643 struct prio_tree_root i_mmap; /* tree of private and shared mappings */ 644 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */ 645 spinlock_t i_mmap_lock; /* protect tree, count, list */ 646 unsigned int truncate_count; /* Cover race condition with truncate */ 647 unsigned long nrpages; /* number of total pages */ 648 pgoff_t writeback_index;/* writeback starts here */ 649 const struct address_space_operations *a_ops; /* methods */ 650 unsigned long flags; /* error bits/gfp mask */ 651 struct backing_dev_info *backing_dev_info; /* device readahead, etc */ 652 spinlock_t private_lock; /* for use by the address_space */ 653 struct list_head private_list; /* ditto */ 654 struct address_space *assoc_mapping; /* ditto */ 655 struct mutex unmap_mutex; /* to protect unmapping */ 656 } __attribute__((aligned(sizeof(long)))); 657 /* 658 * On most architectures that alignment is already the case; but 659 * must be enforced here for CRIS, to let the least signficant bit 660 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON. 661 */ 662 663 struct block_device { 664 dev_t bd_dev; /* not a kdev_t - it's a search key */ 665 int bd_openers; 666 struct inode * bd_inode; /* will die */ 667 struct super_block * bd_super; 668 struct mutex bd_mutex; /* open/close mutex */ 669 struct list_head bd_inodes; 670 void * bd_claiming; 671 void * bd_holder; 672 int bd_holders; 673 bool bd_write_holder; 674 #ifdef CONFIG_SYSFS 675 struct list_head bd_holder_disks; 676 #endif 677 struct block_device * bd_contains; 678 unsigned bd_block_size; 679 struct hd_struct * bd_part; 680 /* number of times partitions within this device have been opened. */ 681 unsigned bd_part_count; 682 int bd_invalidated; 683 struct gendisk * bd_disk; 684 struct list_head bd_list; 685 /* 686 * Private data. You must have bd_claim'ed the block_device 687 * to use this. NOTE: bd_claim allows an owner to claim 688 * the same device multiple times, the owner must take special 689 * care to not mess up bd_private for that case. 690 */ 691 unsigned long bd_private; 692 693 /* The counter of freeze processes */ 694 int bd_fsfreeze_count; 695 /* Mutex for freeze */ 696 struct mutex bd_fsfreeze_mutex; 697 }; 698 699 /* 700 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache 701 * radix trees 702 */ 703 #define PAGECACHE_TAG_DIRTY 0 704 #define PAGECACHE_TAG_WRITEBACK 1 705 #define PAGECACHE_TAG_TOWRITE 2 706 707 int mapping_tagged(struct address_space *mapping, int tag); 708 709 /* 710 * Might pages of this file be mapped into userspace? 711 */ 712 static inline int mapping_mapped(struct address_space *mapping) 713 { 714 return !prio_tree_empty(&mapping->i_mmap) || 715 !list_empty(&mapping->i_mmap_nonlinear); 716 } 717 718 /* 719 * Might pages of this file have been modified in userspace? 720 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff 721 * marks vma as VM_SHARED if it is shared, and the file was opened for 722 * writing i.e. vma may be mprotected writable even if now readonly. 723 */ 724 static inline int mapping_writably_mapped(struct address_space *mapping) 725 { 726 return mapping->i_mmap_writable != 0; 727 } 728 729 /* 730 * Use sequence counter to get consistent i_size on 32-bit processors. 731 */ 732 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 733 #include <linux/seqlock.h> 734 #define __NEED_I_SIZE_ORDERED 735 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount) 736 #else 737 #define i_size_ordered_init(inode) do { } while (0) 738 #endif 739 740 struct posix_acl; 741 #define ACL_NOT_CACHED ((void *)(-1)) 742 743 struct inode { 744 /* RCU path lookup touches following: */ 745 umode_t i_mode; 746 uid_t i_uid; 747 gid_t i_gid; 748 const struct inode_operations *i_op; 749 struct super_block *i_sb; 750 751 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */ 752 unsigned int i_flags; 753 struct mutex i_mutex; 754 755 unsigned long i_state; 756 unsigned long dirtied_when; /* jiffies of first dirtying */ 757 758 struct hlist_node i_hash; 759 struct list_head i_wb_list; /* backing dev IO list */ 760 struct list_head i_lru; /* inode LRU list */ 761 struct list_head i_sb_list; 762 union { 763 struct list_head i_dentry; 764 struct rcu_head i_rcu; 765 }; 766 unsigned long i_ino; 767 atomic_t i_count; 768 unsigned int i_nlink; 769 dev_t i_rdev; 770 unsigned int i_blkbits; 771 u64 i_version; 772 loff_t i_size; 773 #ifdef __NEED_I_SIZE_ORDERED 774 seqcount_t i_size_seqcount; 775 #endif 776 struct timespec i_atime; 777 struct timespec i_mtime; 778 struct timespec i_ctime; 779 blkcnt_t i_blocks; 780 unsigned short i_bytes; 781 struct rw_semaphore i_alloc_sem; 782 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */ 783 struct file_lock *i_flock; 784 struct address_space *i_mapping; 785 struct address_space i_data; 786 #ifdef CONFIG_QUOTA 787 struct dquot *i_dquot[MAXQUOTAS]; 788 #endif 789 struct list_head i_devices; 790 union { 791 struct pipe_inode_info *i_pipe; 792 struct block_device *i_bdev; 793 struct cdev *i_cdev; 794 }; 795 796 __u32 i_generation; 797 798 #ifdef CONFIG_FSNOTIFY 799 __u32 i_fsnotify_mask; /* all events this inode cares about */ 800 struct hlist_head i_fsnotify_marks; 801 #endif 802 803 #ifdef CONFIG_IMA 804 atomic_t i_readcount; /* struct files open RO */ 805 #endif 806 atomic_t i_writecount; 807 #ifdef CONFIG_SECURITY 808 void *i_security; 809 #endif 810 #ifdef CONFIG_FS_POSIX_ACL 811 struct posix_acl *i_acl; 812 struct posix_acl *i_default_acl; 813 #endif 814 void *i_private; /* fs or device private pointer */ 815 }; 816 817 static inline int inode_unhashed(struct inode *inode) 818 { 819 return hlist_unhashed(&inode->i_hash); 820 } 821 822 /* 823 * inode->i_mutex nesting subclasses for the lock validator: 824 * 825 * 0: the object of the current VFS operation 826 * 1: parent 827 * 2: child/target 828 * 3: quota file 829 * 830 * The locking order between these classes is 831 * parent -> child -> normal -> xattr -> quota 832 */ 833 enum inode_i_mutex_lock_class 834 { 835 I_MUTEX_NORMAL, 836 I_MUTEX_PARENT, 837 I_MUTEX_CHILD, 838 I_MUTEX_XATTR, 839 I_MUTEX_QUOTA 840 }; 841 842 /* 843 * NOTE: in a 32bit arch with a preemptable kernel and 844 * an UP compile the i_size_read/write must be atomic 845 * with respect to the local cpu (unlike with preempt disabled), 846 * but they don't need to be atomic with respect to other cpus like in 847 * true SMP (so they need either to either locally disable irq around 848 * the read or for example on x86 they can be still implemented as a 849 * cmpxchg8b without the need of the lock prefix). For SMP compiles 850 * and 64bit archs it makes no difference if preempt is enabled or not. 851 */ 852 static inline loff_t i_size_read(const struct inode *inode) 853 { 854 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 855 loff_t i_size; 856 unsigned int seq; 857 858 do { 859 seq = read_seqcount_begin(&inode->i_size_seqcount); 860 i_size = inode->i_size; 861 } while (read_seqcount_retry(&inode->i_size_seqcount, seq)); 862 return i_size; 863 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 864 loff_t i_size; 865 866 preempt_disable(); 867 i_size = inode->i_size; 868 preempt_enable(); 869 return i_size; 870 #else 871 return inode->i_size; 872 #endif 873 } 874 875 /* 876 * NOTE: unlike i_size_read(), i_size_write() does need locking around it 877 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount 878 * can be lost, resulting in subsequent i_size_read() calls spinning forever. 879 */ 880 static inline void i_size_write(struct inode *inode, loff_t i_size) 881 { 882 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 883 write_seqcount_begin(&inode->i_size_seqcount); 884 inode->i_size = i_size; 885 write_seqcount_end(&inode->i_size_seqcount); 886 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 887 preempt_disable(); 888 inode->i_size = i_size; 889 preempt_enable(); 890 #else 891 inode->i_size = i_size; 892 #endif 893 } 894 895 static inline unsigned iminor(const struct inode *inode) 896 { 897 return MINOR(inode->i_rdev); 898 } 899 900 static inline unsigned imajor(const struct inode *inode) 901 { 902 return MAJOR(inode->i_rdev); 903 } 904 905 extern struct block_device *I_BDEV(struct inode *inode); 906 907 struct fown_struct { 908 rwlock_t lock; /* protects pid, uid, euid fields */ 909 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */ 910 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */ 911 uid_t uid, euid; /* uid/euid of process setting the owner */ 912 int signum; /* posix.1b rt signal to be delivered on IO */ 913 }; 914 915 /* 916 * Track a single file's readahead state 917 */ 918 struct file_ra_state { 919 pgoff_t start; /* where readahead started */ 920 unsigned int size; /* # of readahead pages */ 921 unsigned int async_size; /* do asynchronous readahead when 922 there are only # of pages ahead */ 923 924 unsigned int ra_pages; /* Maximum readahead window */ 925 unsigned int mmap_miss; /* Cache miss stat for mmap accesses */ 926 loff_t prev_pos; /* Cache last read() position */ 927 }; 928 929 /* 930 * Check if @index falls in the readahead windows. 931 */ 932 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index) 933 { 934 return (index >= ra->start && 935 index < ra->start + ra->size); 936 } 937 938 #define FILE_MNT_WRITE_TAKEN 1 939 #define FILE_MNT_WRITE_RELEASED 2 940 941 struct file { 942 /* 943 * fu_list becomes invalid after file_free is called and queued via 944 * fu_rcuhead for RCU freeing 945 */ 946 union { 947 struct list_head fu_list; 948 struct rcu_head fu_rcuhead; 949 } f_u; 950 struct path f_path; 951 #define f_dentry f_path.dentry 952 #define f_vfsmnt f_path.mnt 953 const struct file_operations *f_op; 954 spinlock_t f_lock; /* f_ep_links, f_flags, no IRQ */ 955 #ifdef CONFIG_SMP 956 int f_sb_list_cpu; 957 #endif 958 atomic_long_t f_count; 959 unsigned int f_flags; 960 fmode_t f_mode; 961 loff_t f_pos; 962 struct fown_struct f_owner; 963 const struct cred *f_cred; 964 struct file_ra_state f_ra; 965 966 u64 f_version; 967 #ifdef CONFIG_SECURITY 968 void *f_security; 969 #endif 970 /* needed for tty driver, and maybe others */ 971 void *private_data; 972 973 #ifdef CONFIG_EPOLL 974 /* Used by fs/eventpoll.c to link all the hooks to this file */ 975 struct list_head f_ep_links; 976 #endif /* #ifdef CONFIG_EPOLL */ 977 struct address_space *f_mapping; 978 #ifdef CONFIG_DEBUG_WRITECOUNT 979 unsigned long f_mnt_write_state; 980 #endif 981 }; 982 983 struct file_handle { 984 __u32 handle_bytes; 985 int handle_type; 986 /* file identifier */ 987 unsigned char f_handle[0]; 988 }; 989 990 #define get_file(x) atomic_long_inc(&(x)->f_count) 991 #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1) 992 #define file_count(x) atomic_long_read(&(x)->f_count) 993 994 #ifdef CONFIG_DEBUG_WRITECOUNT 995 static inline void file_take_write(struct file *f) 996 { 997 WARN_ON(f->f_mnt_write_state != 0); 998 f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN; 999 } 1000 static inline void file_release_write(struct file *f) 1001 { 1002 f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED; 1003 } 1004 static inline void file_reset_write(struct file *f) 1005 { 1006 f->f_mnt_write_state = 0; 1007 } 1008 static inline void file_check_state(struct file *f) 1009 { 1010 /* 1011 * At this point, either both or neither of these bits 1012 * should be set. 1013 */ 1014 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN); 1015 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED); 1016 } 1017 static inline int file_check_writeable(struct file *f) 1018 { 1019 if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN) 1020 return 0; 1021 printk(KERN_WARNING "writeable file with no " 1022 "mnt_want_write()\n"); 1023 WARN_ON(1); 1024 return -EINVAL; 1025 } 1026 #else /* !CONFIG_DEBUG_WRITECOUNT */ 1027 static inline void file_take_write(struct file *filp) {} 1028 static inline void file_release_write(struct file *filp) {} 1029 static inline void file_reset_write(struct file *filp) {} 1030 static inline void file_check_state(struct file *filp) {} 1031 static inline int file_check_writeable(struct file *filp) 1032 { 1033 return 0; 1034 } 1035 #endif /* CONFIG_DEBUG_WRITECOUNT */ 1036 1037 #define MAX_NON_LFS ((1UL<<31) - 1) 1038 1039 /* Page cache limit. The filesystems should put that into their s_maxbytes 1040 limits, otherwise bad things can happen in VM. */ 1041 #if BITS_PER_LONG==32 1042 #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1) 1043 #elif BITS_PER_LONG==64 1044 #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL 1045 #endif 1046 1047 #define FL_POSIX 1 1048 #define FL_FLOCK 2 1049 #define FL_ACCESS 8 /* not trying to lock, just looking */ 1050 #define FL_EXISTS 16 /* when unlocking, test for existence */ 1051 #define FL_LEASE 32 /* lease held on this file */ 1052 #define FL_CLOSE 64 /* unlock on close */ 1053 #define FL_SLEEP 128 /* A blocking lock */ 1054 1055 /* 1056 * Special return value from posix_lock_file() and vfs_lock_file() for 1057 * asynchronous locking. 1058 */ 1059 #define FILE_LOCK_DEFERRED 1 1060 1061 /* 1062 * The POSIX file lock owner is determined by 1063 * the "struct files_struct" in the thread group 1064 * (or NULL for no owner - BSD locks). 1065 * 1066 * Lockd stuffs a "host" pointer into this. 1067 */ 1068 typedef struct files_struct *fl_owner_t; 1069 1070 struct file_lock_operations { 1071 void (*fl_copy_lock)(struct file_lock *, struct file_lock *); 1072 void (*fl_release_private)(struct file_lock *); 1073 }; 1074 1075 struct lock_manager_operations { 1076 int (*fl_compare_owner)(struct file_lock *, struct file_lock *); 1077 void (*fl_notify)(struct file_lock *); /* unblock callback */ 1078 int (*fl_grant)(struct file_lock *, struct file_lock *, int); 1079 void (*fl_release_private)(struct file_lock *); 1080 void (*fl_break)(struct file_lock *); 1081 int (*fl_change)(struct file_lock **, int); 1082 }; 1083 1084 struct lock_manager { 1085 struct list_head list; 1086 }; 1087 1088 void locks_start_grace(struct lock_manager *); 1089 void locks_end_grace(struct lock_manager *); 1090 int locks_in_grace(void); 1091 1092 /* that will die - we need it for nfs_lock_info */ 1093 #include <linux/nfs_fs_i.h> 1094 1095 struct file_lock { 1096 struct file_lock *fl_next; /* singly linked list for this inode */ 1097 struct list_head fl_link; /* doubly linked list of all locks */ 1098 struct list_head fl_block; /* circular list of blocked processes */ 1099 fl_owner_t fl_owner; 1100 unsigned char fl_flags; 1101 unsigned char fl_type; 1102 unsigned int fl_pid; 1103 struct pid *fl_nspid; 1104 wait_queue_head_t fl_wait; 1105 struct file *fl_file; 1106 loff_t fl_start; 1107 loff_t fl_end; 1108 1109 struct fasync_struct * fl_fasync; /* for lease break notifications */ 1110 unsigned long fl_break_time; /* for nonblocking lease breaks */ 1111 1112 const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */ 1113 const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */ 1114 union { 1115 struct nfs_lock_info nfs_fl; 1116 struct nfs4_lock_info nfs4_fl; 1117 struct { 1118 struct list_head link; /* link in AFS vnode's pending_locks list */ 1119 int state; /* state of grant or error if -ve */ 1120 } afs; 1121 } fl_u; 1122 }; 1123 1124 /* The following constant reflects the upper bound of the file/locking space */ 1125 #ifndef OFFSET_MAX 1126 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1))) 1127 #define OFFSET_MAX INT_LIMIT(loff_t) 1128 #define OFFT_OFFSET_MAX INT_LIMIT(off_t) 1129 #endif 1130 1131 #include <linux/fcntl.h> 1132 1133 extern void send_sigio(struct fown_struct *fown, int fd, int band); 1134 1135 #ifdef CONFIG_FILE_LOCKING 1136 extern int fcntl_getlk(struct file *, struct flock __user *); 1137 extern int fcntl_setlk(unsigned int, struct file *, unsigned int, 1138 struct flock __user *); 1139 1140 #if BITS_PER_LONG == 32 1141 extern int fcntl_getlk64(struct file *, struct flock64 __user *); 1142 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int, 1143 struct flock64 __user *); 1144 #endif 1145 1146 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg); 1147 extern int fcntl_getlease(struct file *filp); 1148 1149 /* fs/locks.c */ 1150 void locks_free_lock(struct file_lock *fl); 1151 extern void locks_init_lock(struct file_lock *); 1152 extern struct file_lock * locks_alloc_lock(void); 1153 extern void locks_copy_lock(struct file_lock *, struct file_lock *); 1154 extern void __locks_copy_lock(struct file_lock *, const struct file_lock *); 1155 extern void locks_remove_posix(struct file *, fl_owner_t); 1156 extern void locks_remove_flock(struct file *); 1157 extern void locks_release_private(struct file_lock *); 1158 extern void posix_test_lock(struct file *, struct file_lock *); 1159 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *); 1160 extern int posix_lock_file_wait(struct file *, struct file_lock *); 1161 extern int posix_unblock_lock(struct file *, struct file_lock *); 1162 extern int vfs_test_lock(struct file *, struct file_lock *); 1163 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *); 1164 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl); 1165 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl); 1166 extern int __break_lease(struct inode *inode, unsigned int flags); 1167 extern void lease_get_mtime(struct inode *, struct timespec *time); 1168 extern int generic_setlease(struct file *, long, struct file_lock **); 1169 extern int vfs_setlease(struct file *, long, struct file_lock **); 1170 extern int lease_modify(struct file_lock **, int); 1171 extern int lock_may_read(struct inode *, loff_t start, unsigned long count); 1172 extern int lock_may_write(struct inode *, loff_t start, unsigned long count); 1173 extern void lock_flocks(void); 1174 extern void unlock_flocks(void); 1175 #else /* !CONFIG_FILE_LOCKING */ 1176 static inline int fcntl_getlk(struct file *file, struct flock __user *user) 1177 { 1178 return -EINVAL; 1179 } 1180 1181 static inline int fcntl_setlk(unsigned int fd, struct file *file, 1182 unsigned int cmd, struct flock __user *user) 1183 { 1184 return -EACCES; 1185 } 1186 1187 #if BITS_PER_LONG == 32 1188 static inline int fcntl_getlk64(struct file *file, struct flock64 __user *user) 1189 { 1190 return -EINVAL; 1191 } 1192 1193 static inline int fcntl_setlk64(unsigned int fd, struct file *file, 1194 unsigned int cmd, struct flock64 __user *user) 1195 { 1196 return -EACCES; 1197 } 1198 #endif 1199 static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg) 1200 { 1201 return 0; 1202 } 1203 1204 static inline int fcntl_getlease(struct file *filp) 1205 { 1206 return 0; 1207 } 1208 1209 static inline void locks_init_lock(struct file_lock *fl) 1210 { 1211 return; 1212 } 1213 1214 static inline void __locks_copy_lock(struct file_lock *new, struct file_lock *fl) 1215 { 1216 return; 1217 } 1218 1219 static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl) 1220 { 1221 return; 1222 } 1223 1224 static inline void locks_remove_posix(struct file *filp, fl_owner_t owner) 1225 { 1226 return; 1227 } 1228 1229 static inline void locks_remove_flock(struct file *filp) 1230 { 1231 return; 1232 } 1233 1234 static inline void posix_test_lock(struct file *filp, struct file_lock *fl) 1235 { 1236 return; 1237 } 1238 1239 static inline int posix_lock_file(struct file *filp, struct file_lock *fl, 1240 struct file_lock *conflock) 1241 { 1242 return -ENOLCK; 1243 } 1244 1245 static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl) 1246 { 1247 return -ENOLCK; 1248 } 1249 1250 static inline int posix_unblock_lock(struct file *filp, 1251 struct file_lock *waiter) 1252 { 1253 return -ENOENT; 1254 } 1255 1256 static inline int vfs_test_lock(struct file *filp, struct file_lock *fl) 1257 { 1258 return 0; 1259 } 1260 1261 static inline int vfs_lock_file(struct file *filp, unsigned int cmd, 1262 struct file_lock *fl, struct file_lock *conf) 1263 { 1264 return -ENOLCK; 1265 } 1266 1267 static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl) 1268 { 1269 return 0; 1270 } 1271 1272 static inline int flock_lock_file_wait(struct file *filp, 1273 struct file_lock *request) 1274 { 1275 return -ENOLCK; 1276 } 1277 1278 static inline int __break_lease(struct inode *inode, unsigned int mode) 1279 { 1280 return 0; 1281 } 1282 1283 static inline void lease_get_mtime(struct inode *inode, struct timespec *time) 1284 { 1285 return; 1286 } 1287 1288 static inline int generic_setlease(struct file *filp, long arg, 1289 struct file_lock **flp) 1290 { 1291 return -EINVAL; 1292 } 1293 1294 static inline int vfs_setlease(struct file *filp, long arg, 1295 struct file_lock **lease) 1296 { 1297 return -EINVAL; 1298 } 1299 1300 static inline int lease_modify(struct file_lock **before, int arg) 1301 { 1302 return -EINVAL; 1303 } 1304 1305 static inline int lock_may_read(struct inode *inode, loff_t start, 1306 unsigned long len) 1307 { 1308 return 1; 1309 } 1310 1311 static inline int lock_may_write(struct inode *inode, loff_t start, 1312 unsigned long len) 1313 { 1314 return 1; 1315 } 1316 1317 static inline void lock_flocks(void) 1318 { 1319 } 1320 1321 static inline void unlock_flocks(void) 1322 { 1323 } 1324 1325 #endif /* !CONFIG_FILE_LOCKING */ 1326 1327 1328 struct fasync_struct { 1329 spinlock_t fa_lock; 1330 int magic; 1331 int fa_fd; 1332 struct fasync_struct *fa_next; /* singly linked list */ 1333 struct file *fa_file; 1334 struct rcu_head fa_rcu; 1335 }; 1336 1337 #define FASYNC_MAGIC 0x4601 1338 1339 /* SMP safe fasync helpers: */ 1340 extern int fasync_helper(int, struct file *, int, struct fasync_struct **); 1341 extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *); 1342 extern int fasync_remove_entry(struct file *, struct fasync_struct **); 1343 extern struct fasync_struct *fasync_alloc(void); 1344 extern void fasync_free(struct fasync_struct *); 1345 1346 /* can be called from interrupts */ 1347 extern void kill_fasync(struct fasync_struct **, int, int); 1348 1349 extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force); 1350 extern int f_setown(struct file *filp, unsigned long arg, int force); 1351 extern void f_delown(struct file *filp); 1352 extern pid_t f_getown(struct file *filp); 1353 extern int send_sigurg(struct fown_struct *fown); 1354 1355 /* 1356 * Umount options 1357 */ 1358 1359 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */ 1360 #define MNT_DETACH 0x00000002 /* Just detach from the tree */ 1361 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */ 1362 #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */ 1363 #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */ 1364 1365 extern struct list_head super_blocks; 1366 extern spinlock_t sb_lock; 1367 1368 struct super_block { 1369 struct list_head s_list; /* Keep this first */ 1370 dev_t s_dev; /* search index; _not_ kdev_t */ 1371 unsigned char s_dirt; 1372 unsigned char s_blocksize_bits; 1373 unsigned long s_blocksize; 1374 loff_t s_maxbytes; /* Max file size */ 1375 struct file_system_type *s_type; 1376 const struct super_operations *s_op; 1377 const struct dquot_operations *dq_op; 1378 const struct quotactl_ops *s_qcop; 1379 const struct export_operations *s_export_op; 1380 unsigned long s_flags; 1381 unsigned long s_magic; 1382 struct dentry *s_root; 1383 struct rw_semaphore s_umount; 1384 struct mutex s_lock; 1385 int s_count; 1386 atomic_t s_active; 1387 #ifdef CONFIG_SECURITY 1388 void *s_security; 1389 #endif 1390 const struct xattr_handler **s_xattr; 1391 1392 struct list_head s_inodes; /* all inodes */ 1393 struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */ 1394 #ifdef CONFIG_SMP 1395 struct list_head __percpu *s_files; 1396 #else 1397 struct list_head s_files; 1398 #endif 1399 /* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */ 1400 struct list_head s_dentry_lru; /* unused dentry lru */ 1401 int s_nr_dentry_unused; /* # of dentry on lru */ 1402 1403 struct block_device *s_bdev; 1404 struct backing_dev_info *s_bdi; 1405 struct mtd_info *s_mtd; 1406 struct list_head s_instances; 1407 struct quota_info s_dquot; /* Diskquota specific options */ 1408 1409 int s_frozen; 1410 wait_queue_head_t s_wait_unfrozen; 1411 1412 char s_id[32]; /* Informational name */ 1413 u8 s_uuid[16]; /* UUID */ 1414 1415 void *s_fs_info; /* Filesystem private info */ 1416 fmode_t s_mode; 1417 1418 /* Granularity of c/m/atime in ns. 1419 Cannot be worse than a second */ 1420 u32 s_time_gran; 1421 1422 /* 1423 * The next field is for VFS *only*. No filesystems have any business 1424 * even looking at it. You had been warned. 1425 */ 1426 struct mutex s_vfs_rename_mutex; /* Kludge */ 1427 1428 /* 1429 * Filesystem subtype. If non-empty the filesystem type field 1430 * in /proc/mounts will be "type.subtype" 1431 */ 1432 char *s_subtype; 1433 1434 /* 1435 * Saved mount options for lazy filesystems using 1436 * generic_show_options() 1437 */ 1438 char __rcu *s_options; 1439 const struct dentry_operations *s_d_op; /* default d_op for dentries */ 1440 }; 1441 1442 extern struct timespec current_fs_time(struct super_block *sb); 1443 1444 /* 1445 * Snapshotting support. 1446 */ 1447 enum { 1448 SB_UNFROZEN = 0, 1449 SB_FREEZE_WRITE = 1, 1450 SB_FREEZE_TRANS = 2, 1451 }; 1452 1453 #define vfs_check_frozen(sb, level) \ 1454 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level))) 1455 1456 #define get_fs_excl() atomic_inc(¤t->fs_excl) 1457 #define put_fs_excl() atomic_dec(¤t->fs_excl) 1458 #define has_fs_excl() atomic_read(¤t->fs_excl) 1459 1460 #define is_owner_or_cap(inode) \ 1461 ((current_fsuid() == (inode)->i_uid) || capable(CAP_FOWNER)) 1462 1463 /* not quite ready to be deprecated, but... */ 1464 extern void lock_super(struct super_block *); 1465 extern void unlock_super(struct super_block *); 1466 1467 /* 1468 * VFS helper functions.. 1469 */ 1470 extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *); 1471 extern int vfs_mkdir(struct inode *, struct dentry *, int); 1472 extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t); 1473 extern int vfs_symlink(struct inode *, struct dentry *, const char *); 1474 extern int vfs_link(struct dentry *, struct inode *, struct dentry *); 1475 extern int vfs_rmdir(struct inode *, struct dentry *); 1476 extern int vfs_unlink(struct inode *, struct dentry *); 1477 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); 1478 1479 /* 1480 * VFS dentry helper functions. 1481 */ 1482 extern void dentry_unhash(struct dentry *dentry); 1483 1484 /* 1485 * VFS file helper functions. 1486 */ 1487 extern int file_permission(struct file *, int); 1488 extern void inode_init_owner(struct inode *inode, const struct inode *dir, 1489 mode_t mode); 1490 /* 1491 * VFS FS_IOC_FIEMAP helper definitions. 1492 */ 1493 struct fiemap_extent_info { 1494 unsigned int fi_flags; /* Flags as passed from user */ 1495 unsigned int fi_extents_mapped; /* Number of mapped extents */ 1496 unsigned int fi_extents_max; /* Size of fiemap_extent array */ 1497 struct fiemap_extent __user *fi_extents_start; /* Start of 1498 fiemap_extent array */ 1499 }; 1500 int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical, 1501 u64 phys, u64 len, u32 flags); 1502 int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); 1503 1504 /* 1505 * File types 1506 * 1507 * NOTE! These match bits 12..15 of stat.st_mode 1508 * (ie "(i_mode >> 12) & 15"). 1509 */ 1510 #define DT_UNKNOWN 0 1511 #define DT_FIFO 1 1512 #define DT_CHR 2 1513 #define DT_DIR 4 1514 #define DT_BLK 6 1515 #define DT_REG 8 1516 #define DT_LNK 10 1517 #define DT_SOCK 12 1518 #define DT_WHT 14 1519 1520 /* 1521 * This is the "filldir" function type, used by readdir() to let 1522 * the kernel specify what kind of dirent layout it wants to have. 1523 * This allows the kernel to read directories into kernel space or 1524 * to have different dirent layouts depending on the binary type. 1525 */ 1526 typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned); 1527 struct block_device_operations; 1528 1529 /* These macros are for out of kernel modules to test that 1530 * the kernel supports the unlocked_ioctl and compat_ioctl 1531 * fields in struct file_operations. */ 1532 #define HAVE_COMPAT_IOCTL 1 1533 #define HAVE_UNLOCKED_IOCTL 1 1534 1535 /* 1536 * NOTE: 1537 * all file operations except setlease can be called without 1538 * the big kernel lock held in all filesystems. 1539 */ 1540 struct file_operations { 1541 struct module *owner; 1542 loff_t (*llseek) (struct file *, loff_t, int); 1543 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); 1544 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); 1545 ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t); 1546 ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); 1547 int (*readdir) (struct file *, void *, filldir_t); 1548 unsigned int (*poll) (struct file *, struct poll_table_struct *); 1549 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); 1550 long (*compat_ioctl) (struct file *, unsigned int, unsigned long); 1551 int (*mmap) (struct file *, struct vm_area_struct *); 1552 int (*open) (struct inode *, struct file *); 1553 int (*flush) (struct file *, fl_owner_t id); 1554 int (*release) (struct inode *, struct file *); 1555 int (*fsync) (struct file *, int datasync); 1556 int (*aio_fsync) (struct kiocb *, int datasync); 1557 int (*fasync) (int, struct file *, int); 1558 int (*lock) (struct file *, int, struct file_lock *); 1559 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int); 1560 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1561 int (*check_flags)(int); 1562 int (*flock) (struct file *, int, struct file_lock *); 1563 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); 1564 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); 1565 int (*setlease)(struct file *, long, struct file_lock **); 1566 long (*fallocate)(struct file *file, int mode, loff_t offset, 1567 loff_t len); 1568 }; 1569 1570 #define IPERM_FLAG_RCU 0x0001 1571 1572 struct inode_operations { 1573 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *); 1574 void * (*follow_link) (struct dentry *, struct nameidata *); 1575 int (*permission) (struct inode *, int, unsigned int); 1576 int (*check_acl)(struct inode *, int, unsigned int); 1577 1578 int (*readlink) (struct dentry *, char __user *,int); 1579 void (*put_link) (struct dentry *, struct nameidata *, void *); 1580 1581 int (*create) (struct inode *,struct dentry *,int, struct nameidata *); 1582 int (*link) (struct dentry *,struct inode *,struct dentry *); 1583 int (*unlink) (struct inode *,struct dentry *); 1584 int (*symlink) (struct inode *,struct dentry *,const char *); 1585 int (*mkdir) (struct inode *,struct dentry *,int); 1586 int (*rmdir) (struct inode *,struct dentry *); 1587 int (*mknod) (struct inode *,struct dentry *,int,dev_t); 1588 int (*rename) (struct inode *, struct dentry *, 1589 struct inode *, struct dentry *); 1590 void (*truncate) (struct inode *); 1591 int (*setattr) (struct dentry *, struct iattr *); 1592 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *); 1593 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); 1594 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t); 1595 ssize_t (*listxattr) (struct dentry *, char *, size_t); 1596 int (*removexattr) (struct dentry *, const char *); 1597 void (*truncate_range)(struct inode *, loff_t, loff_t); 1598 int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, 1599 u64 len); 1600 } ____cacheline_aligned; 1601 1602 struct seq_file; 1603 1604 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, 1605 unsigned long nr_segs, unsigned long fast_segs, 1606 struct iovec *fast_pointer, 1607 struct iovec **ret_pointer); 1608 1609 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); 1610 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); 1611 extern ssize_t vfs_readv(struct file *, const struct iovec __user *, 1612 unsigned long, loff_t *); 1613 extern ssize_t vfs_writev(struct file *, const struct iovec __user *, 1614 unsigned long, loff_t *); 1615 1616 struct super_operations { 1617 struct inode *(*alloc_inode)(struct super_block *sb); 1618 void (*destroy_inode)(struct inode *); 1619 1620 void (*dirty_inode) (struct inode *); 1621 int (*write_inode) (struct inode *, struct writeback_control *wbc); 1622 int (*drop_inode) (struct inode *); 1623 void (*evict_inode) (struct inode *); 1624 void (*put_super) (struct super_block *); 1625 void (*write_super) (struct super_block *); 1626 int (*sync_fs)(struct super_block *sb, int wait); 1627 int (*freeze_fs) (struct super_block *); 1628 int (*unfreeze_fs) (struct super_block *); 1629 int (*statfs) (struct dentry *, struct kstatfs *); 1630 int (*remount_fs) (struct super_block *, int *, char *); 1631 void (*umount_begin) (struct super_block *); 1632 1633 int (*show_options)(struct seq_file *, struct vfsmount *); 1634 int (*show_devname)(struct seq_file *, struct vfsmount *); 1635 int (*show_path)(struct seq_file *, struct vfsmount *); 1636 int (*show_stats)(struct seq_file *, struct vfsmount *); 1637 #ifdef CONFIG_QUOTA 1638 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t); 1639 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); 1640 #endif 1641 int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t); 1642 }; 1643 1644 /* 1645 * Inode state bits. Protected by inode_lock. 1646 * 1647 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC, 1648 * I_DIRTY_DATASYNC and I_DIRTY_PAGES. 1649 * 1650 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW, 1651 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at 1652 * various stages of removing an inode. 1653 * 1654 * Two bits are used for locking and completion notification, I_NEW and I_SYNC. 1655 * 1656 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on 1657 * fdatasync(). i_atime is the usual cause. 1658 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of 1659 * these changes separately from I_DIRTY_SYNC so that we 1660 * don't have to write inode on fdatasync() when only 1661 * mtime has changed in it. 1662 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean. 1663 * I_NEW Serves as both a mutex and completion notification. 1664 * New inodes set I_NEW. If two processes both create 1665 * the same inode, one of them will release its inode and 1666 * wait for I_NEW to be released before returning. 1667 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can 1668 * also cause waiting on I_NEW, without I_NEW actually 1669 * being set. find_inode() uses this to prevent returning 1670 * nearly-dead inodes. 1671 * I_WILL_FREE Must be set when calling write_inode_now() if i_count 1672 * is zero. I_FREEING must be set when I_WILL_FREE is 1673 * cleared. 1674 * I_FREEING Set when inode is about to be freed but still has dirty 1675 * pages or buffers attached or the inode itself is still 1676 * dirty. 1677 * I_CLEAR Added by end_writeback(). In this state the inode is clean 1678 * and can be destroyed. Inode keeps I_FREEING. 1679 * 1680 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are 1681 * prohibited for many purposes. iget() must wait for 1682 * the inode to be completely released, then create it 1683 * anew. Other functions will just ignore such inodes, 1684 * if appropriate. I_NEW is used for waiting. 1685 * 1686 * I_SYNC Synchonized write of dirty inode data. The bits is 1687 * set during data writeback, and cleared with a wakeup 1688 * on the bit address once it is done. 1689 * 1690 * Q: What is the difference between I_WILL_FREE and I_FREEING? 1691 */ 1692 #define I_DIRTY_SYNC (1 << 0) 1693 #define I_DIRTY_DATASYNC (1 << 1) 1694 #define I_DIRTY_PAGES (1 << 2) 1695 #define __I_NEW 3 1696 #define I_NEW (1 << __I_NEW) 1697 #define I_WILL_FREE (1 << 4) 1698 #define I_FREEING (1 << 5) 1699 #define I_CLEAR (1 << 6) 1700 #define __I_SYNC 7 1701 #define I_SYNC (1 << __I_SYNC) 1702 #define I_REFERENCED (1 << 8) 1703 1704 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES) 1705 1706 extern void __mark_inode_dirty(struct inode *, int); 1707 static inline void mark_inode_dirty(struct inode *inode) 1708 { 1709 __mark_inode_dirty(inode, I_DIRTY); 1710 } 1711 1712 static inline void mark_inode_dirty_sync(struct inode *inode) 1713 { 1714 __mark_inode_dirty(inode, I_DIRTY_SYNC); 1715 } 1716 1717 /** 1718 * inc_nlink - directly increment an inode's link count 1719 * @inode: inode 1720 * 1721 * This is a low-level filesystem helper to replace any 1722 * direct filesystem manipulation of i_nlink. Currently, 1723 * it is only here for parity with dec_nlink(). 1724 */ 1725 static inline void inc_nlink(struct inode *inode) 1726 { 1727 inode->i_nlink++; 1728 } 1729 1730 static inline void inode_inc_link_count(struct inode *inode) 1731 { 1732 inc_nlink(inode); 1733 mark_inode_dirty(inode); 1734 } 1735 1736 /** 1737 * drop_nlink - directly drop an inode's link count 1738 * @inode: inode 1739 * 1740 * This is a low-level filesystem helper to replace any 1741 * direct filesystem manipulation of i_nlink. In cases 1742 * where we are attempting to track writes to the 1743 * filesystem, a decrement to zero means an imminent 1744 * write when the file is truncated and actually unlinked 1745 * on the filesystem. 1746 */ 1747 static inline void drop_nlink(struct inode *inode) 1748 { 1749 inode->i_nlink--; 1750 } 1751 1752 /** 1753 * clear_nlink - directly zero an inode's link count 1754 * @inode: inode 1755 * 1756 * This is a low-level filesystem helper to replace any 1757 * direct filesystem manipulation of i_nlink. See 1758 * drop_nlink() for why we care about i_nlink hitting zero. 1759 */ 1760 static inline void clear_nlink(struct inode *inode) 1761 { 1762 inode->i_nlink = 0; 1763 } 1764 1765 static inline void inode_dec_link_count(struct inode *inode) 1766 { 1767 drop_nlink(inode); 1768 mark_inode_dirty(inode); 1769 } 1770 1771 /** 1772 * inode_inc_iversion - increments i_version 1773 * @inode: inode that need to be updated 1774 * 1775 * Every time the inode is modified, the i_version field will be incremented. 1776 * The filesystem has to be mounted with i_version flag 1777 */ 1778 1779 static inline void inode_inc_iversion(struct inode *inode) 1780 { 1781 spin_lock(&inode->i_lock); 1782 inode->i_version++; 1783 spin_unlock(&inode->i_lock); 1784 } 1785 1786 extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry); 1787 static inline void file_accessed(struct file *file) 1788 { 1789 if (!(file->f_flags & O_NOATIME)) 1790 touch_atime(file->f_path.mnt, file->f_path.dentry); 1791 } 1792 1793 int sync_inode(struct inode *inode, struct writeback_control *wbc); 1794 int sync_inode_metadata(struct inode *inode, int wait); 1795 1796 struct file_system_type { 1797 const char *name; 1798 int fs_flags; 1799 struct dentry *(*mount) (struct file_system_type *, int, 1800 const char *, void *); 1801 void (*kill_sb) (struct super_block *); 1802 struct module *owner; 1803 struct file_system_type * next; 1804 struct list_head fs_supers; 1805 1806 struct lock_class_key s_lock_key; 1807 struct lock_class_key s_umount_key; 1808 struct lock_class_key s_vfs_rename_key; 1809 1810 struct lock_class_key i_lock_key; 1811 struct lock_class_key i_mutex_key; 1812 struct lock_class_key i_mutex_dir_key; 1813 struct lock_class_key i_alloc_sem_key; 1814 }; 1815 1816 extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags, 1817 void *data, int (*fill_super)(struct super_block *, void *, int)); 1818 extern struct dentry *mount_bdev(struct file_system_type *fs_type, 1819 int flags, const char *dev_name, void *data, 1820 int (*fill_super)(struct super_block *, void *, int)); 1821 extern struct dentry *mount_single(struct file_system_type *fs_type, 1822 int flags, void *data, 1823 int (*fill_super)(struct super_block *, void *, int)); 1824 extern struct dentry *mount_nodev(struct file_system_type *fs_type, 1825 int flags, void *data, 1826 int (*fill_super)(struct super_block *, void *, int)); 1827 void generic_shutdown_super(struct super_block *sb); 1828 void kill_block_super(struct super_block *sb); 1829 void kill_anon_super(struct super_block *sb); 1830 void kill_litter_super(struct super_block *sb); 1831 void deactivate_super(struct super_block *sb); 1832 void deactivate_locked_super(struct super_block *sb); 1833 int set_anon_super(struct super_block *s, void *data); 1834 struct super_block *sget(struct file_system_type *type, 1835 int (*test)(struct super_block *,void *), 1836 int (*set)(struct super_block *,void *), 1837 void *data); 1838 extern struct dentry *mount_pseudo(struct file_system_type *, char *, 1839 const struct super_operations *ops, 1840 const struct dentry_operations *dops, 1841 unsigned long); 1842 1843 static inline void sb_mark_dirty(struct super_block *sb) 1844 { 1845 sb->s_dirt = 1; 1846 } 1847 static inline void sb_mark_clean(struct super_block *sb) 1848 { 1849 sb->s_dirt = 0; 1850 } 1851 static inline int sb_is_dirty(struct super_block *sb) 1852 { 1853 return sb->s_dirt; 1854 } 1855 1856 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */ 1857 #define fops_get(fops) \ 1858 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL)) 1859 #define fops_put(fops) \ 1860 do { if (fops) module_put((fops)->owner); } while(0) 1861 1862 extern int register_filesystem(struct file_system_type *); 1863 extern int unregister_filesystem(struct file_system_type *); 1864 extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data); 1865 #define kern_mount(type) kern_mount_data(type, NULL) 1866 extern int may_umount_tree(struct vfsmount *); 1867 extern int may_umount(struct vfsmount *); 1868 extern long do_mount(char *, char *, char *, unsigned long, void *); 1869 extern struct vfsmount *collect_mounts(struct path *); 1870 extern void drop_collected_mounts(struct vfsmount *); 1871 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *, 1872 struct vfsmount *); 1873 extern int vfs_statfs(struct path *, struct kstatfs *); 1874 extern int user_statfs(const char __user *, struct kstatfs *); 1875 extern int fd_statfs(int, struct kstatfs *); 1876 extern int statfs_by_dentry(struct dentry *, struct kstatfs *); 1877 extern int freeze_super(struct super_block *super); 1878 extern int thaw_super(struct super_block *super); 1879 1880 extern int current_umask(void); 1881 1882 /* /sys/fs */ 1883 extern struct kobject *fs_kobj; 1884 1885 #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK) 1886 extern int rw_verify_area(int, struct file *, loff_t *, size_t); 1887 1888 #define FLOCK_VERIFY_READ 1 1889 #define FLOCK_VERIFY_WRITE 2 1890 1891 #ifdef CONFIG_FILE_LOCKING 1892 extern int locks_mandatory_locked(struct inode *); 1893 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t); 1894 1895 /* 1896 * Candidates for mandatory locking have the setgid bit set 1897 * but no group execute bit - an otherwise meaningless combination. 1898 */ 1899 1900 static inline int __mandatory_lock(struct inode *ino) 1901 { 1902 return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID; 1903 } 1904 1905 /* 1906 * ... and these candidates should be on MS_MANDLOCK mounted fs, 1907 * otherwise these will be advisory locks 1908 */ 1909 1910 static inline int mandatory_lock(struct inode *ino) 1911 { 1912 return IS_MANDLOCK(ino) && __mandatory_lock(ino); 1913 } 1914 1915 static inline int locks_verify_locked(struct inode *inode) 1916 { 1917 if (mandatory_lock(inode)) 1918 return locks_mandatory_locked(inode); 1919 return 0; 1920 } 1921 1922 static inline int locks_verify_truncate(struct inode *inode, 1923 struct file *filp, 1924 loff_t size) 1925 { 1926 if (inode->i_flock && mandatory_lock(inode)) 1927 return locks_mandatory_area( 1928 FLOCK_VERIFY_WRITE, inode, filp, 1929 size < inode->i_size ? size : inode->i_size, 1930 (size < inode->i_size ? inode->i_size - size 1931 : size - inode->i_size) 1932 ); 1933 return 0; 1934 } 1935 1936 static inline int break_lease(struct inode *inode, unsigned int mode) 1937 { 1938 if (inode->i_flock) 1939 return __break_lease(inode, mode); 1940 return 0; 1941 } 1942 #else /* !CONFIG_FILE_LOCKING */ 1943 static inline int locks_mandatory_locked(struct inode *inode) 1944 { 1945 return 0; 1946 } 1947 1948 static inline int locks_mandatory_area(int rw, struct inode *inode, 1949 struct file *filp, loff_t offset, 1950 size_t count) 1951 { 1952 return 0; 1953 } 1954 1955 static inline int __mandatory_lock(struct inode *inode) 1956 { 1957 return 0; 1958 } 1959 1960 static inline int mandatory_lock(struct inode *inode) 1961 { 1962 return 0; 1963 } 1964 1965 static inline int locks_verify_locked(struct inode *inode) 1966 { 1967 return 0; 1968 } 1969 1970 static inline int locks_verify_truncate(struct inode *inode, struct file *filp, 1971 size_t size) 1972 { 1973 return 0; 1974 } 1975 1976 static inline int break_lease(struct inode *inode, unsigned int mode) 1977 { 1978 return 0; 1979 } 1980 1981 #endif /* CONFIG_FILE_LOCKING */ 1982 1983 /* fs/open.c */ 1984 1985 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs, 1986 struct file *filp); 1987 extern int do_fallocate(struct file *file, int mode, loff_t offset, 1988 loff_t len); 1989 extern long do_sys_open(int dfd, const char __user *filename, int flags, 1990 int mode); 1991 extern struct file *filp_open(const char *, int, int); 1992 extern struct file *file_open_root(struct dentry *, struct vfsmount *, 1993 const char *, int); 1994 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int, 1995 const struct cred *); 1996 extern int filp_close(struct file *, fl_owner_t id); 1997 extern char * getname(const char __user *); 1998 1999 /* fs/ioctl.c */ 2000 2001 extern int ioctl_preallocate(struct file *filp, void __user *argp); 2002 2003 /* fs/dcache.c */ 2004 extern void __init vfs_caches_init_early(void); 2005 extern void __init vfs_caches_init(unsigned long); 2006 2007 extern struct kmem_cache *names_cachep; 2008 2009 #define __getname_gfp(gfp) kmem_cache_alloc(names_cachep, (gfp)) 2010 #define __getname() __getname_gfp(GFP_KERNEL) 2011 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name)) 2012 #ifndef CONFIG_AUDITSYSCALL 2013 #define putname(name) __putname(name) 2014 #else 2015 extern void putname(const char *name); 2016 #endif 2017 2018 #ifdef CONFIG_BLOCK 2019 extern int register_blkdev(unsigned int, const char *); 2020 extern void unregister_blkdev(unsigned int, const char *); 2021 extern struct block_device *bdget(dev_t); 2022 extern struct block_device *bdgrab(struct block_device *bdev); 2023 extern void bd_set_size(struct block_device *, loff_t size); 2024 extern void bd_forget(struct inode *inode); 2025 extern void bdput(struct block_device *); 2026 extern void invalidate_bdev(struct block_device *); 2027 extern int sync_blockdev(struct block_device *bdev); 2028 extern struct super_block *freeze_bdev(struct block_device *); 2029 extern void emergency_thaw_all(void); 2030 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb); 2031 extern int fsync_bdev(struct block_device *); 2032 #else 2033 static inline void bd_forget(struct inode *inode) {} 2034 static inline int sync_blockdev(struct block_device *bdev) { return 0; } 2035 static inline void invalidate_bdev(struct block_device *bdev) {} 2036 2037 static inline struct super_block *freeze_bdev(struct block_device *sb) 2038 { 2039 return NULL; 2040 } 2041 2042 static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb) 2043 { 2044 return 0; 2045 } 2046 #endif 2047 extern int sync_filesystem(struct super_block *); 2048 extern const struct file_operations def_blk_fops; 2049 extern const struct file_operations def_chr_fops; 2050 extern const struct file_operations bad_sock_fops; 2051 extern const struct file_operations def_fifo_fops; 2052 #ifdef CONFIG_BLOCK 2053 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long); 2054 extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long); 2055 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long); 2056 extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder); 2057 extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode, 2058 void *holder); 2059 extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, 2060 void *holder); 2061 extern int blkdev_put(struct block_device *bdev, fmode_t mode); 2062 #ifdef CONFIG_SYSFS 2063 extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk); 2064 extern void bd_unlink_disk_holder(struct block_device *bdev, 2065 struct gendisk *disk); 2066 #else 2067 static inline int bd_link_disk_holder(struct block_device *bdev, 2068 struct gendisk *disk) 2069 { 2070 return 0; 2071 } 2072 static inline void bd_unlink_disk_holder(struct block_device *bdev, 2073 struct gendisk *disk) 2074 { 2075 } 2076 #endif 2077 #endif 2078 2079 /* fs/char_dev.c */ 2080 #define CHRDEV_MAJOR_HASH_SIZE 255 2081 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *); 2082 extern int register_chrdev_region(dev_t, unsigned, const char *); 2083 extern int __register_chrdev(unsigned int major, unsigned int baseminor, 2084 unsigned int count, const char *name, 2085 const struct file_operations *fops); 2086 extern void __unregister_chrdev(unsigned int major, unsigned int baseminor, 2087 unsigned int count, const char *name); 2088 extern void unregister_chrdev_region(dev_t, unsigned); 2089 extern void chrdev_show(struct seq_file *,off_t); 2090 2091 static inline int register_chrdev(unsigned int major, const char *name, 2092 const struct file_operations *fops) 2093 { 2094 return __register_chrdev(major, 0, 256, name, fops); 2095 } 2096 2097 static inline void unregister_chrdev(unsigned int major, const char *name) 2098 { 2099 __unregister_chrdev(major, 0, 256, name); 2100 } 2101 2102 /* fs/block_dev.c */ 2103 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */ 2104 #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */ 2105 2106 #ifdef CONFIG_BLOCK 2107 #define BLKDEV_MAJOR_HASH_SIZE 255 2108 extern const char *__bdevname(dev_t, char *buffer); 2109 extern const char *bdevname(struct block_device *bdev, char *buffer); 2110 extern struct block_device *lookup_bdev(const char *); 2111 extern void blkdev_show(struct seq_file *,off_t); 2112 2113 #else 2114 #define BLKDEV_MAJOR_HASH_SIZE 0 2115 #endif 2116 2117 extern void init_special_inode(struct inode *, umode_t, dev_t); 2118 2119 /* Invalid inode operations -- fs/bad_inode.c */ 2120 extern void make_bad_inode(struct inode *); 2121 extern int is_bad_inode(struct inode *); 2122 2123 extern const struct file_operations read_pipefifo_fops; 2124 extern const struct file_operations write_pipefifo_fops; 2125 extern const struct file_operations rdwr_pipefifo_fops; 2126 2127 extern int fs_may_remount_ro(struct super_block *); 2128 2129 #ifdef CONFIG_BLOCK 2130 /* 2131 * return READ, READA, or WRITE 2132 */ 2133 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK)) 2134 2135 /* 2136 * return data direction, READ or WRITE 2137 */ 2138 #define bio_data_dir(bio) ((bio)->bi_rw & 1) 2139 2140 extern void check_disk_size_change(struct gendisk *disk, 2141 struct block_device *bdev); 2142 extern int revalidate_disk(struct gendisk *); 2143 extern int check_disk_change(struct block_device *); 2144 extern int __invalidate_device(struct block_device *, bool); 2145 extern int invalidate_partition(struct gendisk *, int); 2146 #endif 2147 unsigned long invalidate_mapping_pages(struct address_space *mapping, 2148 pgoff_t start, pgoff_t end); 2149 2150 static inline void invalidate_remote_inode(struct inode *inode) 2151 { 2152 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2153 S_ISLNK(inode->i_mode)) 2154 invalidate_mapping_pages(inode->i_mapping, 0, -1); 2155 } 2156 extern int invalidate_inode_pages2(struct address_space *mapping); 2157 extern int invalidate_inode_pages2_range(struct address_space *mapping, 2158 pgoff_t start, pgoff_t end); 2159 extern int write_inode_now(struct inode *, int); 2160 extern int filemap_fdatawrite(struct address_space *); 2161 extern int filemap_flush(struct address_space *); 2162 extern int filemap_fdatawait(struct address_space *); 2163 extern int filemap_fdatawait_range(struct address_space *, loff_t lstart, 2164 loff_t lend); 2165 extern int filemap_write_and_wait(struct address_space *mapping); 2166 extern int filemap_write_and_wait_range(struct address_space *mapping, 2167 loff_t lstart, loff_t lend); 2168 extern int __filemap_fdatawrite_range(struct address_space *mapping, 2169 loff_t start, loff_t end, int sync_mode); 2170 extern int filemap_fdatawrite_range(struct address_space *mapping, 2171 loff_t start, loff_t end); 2172 2173 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end, 2174 int datasync); 2175 extern int vfs_fsync(struct file *file, int datasync); 2176 extern int generic_write_sync(struct file *file, loff_t pos, loff_t count); 2177 extern void sync_supers(void); 2178 extern void emergency_sync(void); 2179 extern void emergency_remount(void); 2180 #ifdef CONFIG_BLOCK 2181 extern sector_t bmap(struct inode *, sector_t); 2182 #endif 2183 extern int notify_change(struct dentry *, struct iattr *); 2184 extern int inode_permission(struct inode *, int); 2185 extern int generic_permission(struct inode *, int, unsigned int, 2186 int (*check_acl)(struct inode *, int, unsigned int)); 2187 2188 static inline bool execute_ok(struct inode *inode) 2189 { 2190 return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode); 2191 } 2192 2193 extern int get_write_access(struct inode *); 2194 extern int deny_write_access(struct file *); 2195 static inline void put_write_access(struct inode * inode) 2196 { 2197 atomic_dec(&inode->i_writecount); 2198 } 2199 static inline void allow_write_access(struct file *file) 2200 { 2201 if (file) 2202 atomic_inc(&file->f_path.dentry->d_inode->i_writecount); 2203 } 2204 #ifdef CONFIG_IMA 2205 static inline void i_readcount_dec(struct inode *inode) 2206 { 2207 BUG_ON(!atomic_read(&inode->i_readcount)); 2208 atomic_dec(&inode->i_readcount); 2209 } 2210 static inline void i_readcount_inc(struct inode *inode) 2211 { 2212 atomic_inc(&inode->i_readcount); 2213 } 2214 #else 2215 static inline void i_readcount_dec(struct inode *inode) 2216 { 2217 return; 2218 } 2219 static inline void i_readcount_inc(struct inode *inode) 2220 { 2221 return; 2222 } 2223 #endif 2224 extern int do_pipe_flags(int *, int); 2225 extern struct file *create_read_pipe(struct file *f, int flags); 2226 extern struct file *create_write_pipe(int flags); 2227 extern void free_write_pipe(struct file *); 2228 2229 extern int kernel_read(struct file *, loff_t, char *, unsigned long); 2230 extern struct file * open_exec(const char *); 2231 2232 /* fs/dcache.c -- generic fs support functions */ 2233 extern int is_subdir(struct dentry *, struct dentry *); 2234 extern int path_is_under(struct path *, struct path *); 2235 extern ino_t find_inode_number(struct dentry *, struct qstr *); 2236 2237 #include <linux/err.h> 2238 2239 /* needed for stackable file system support */ 2240 extern loff_t default_llseek(struct file *file, loff_t offset, int origin); 2241 2242 extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin); 2243 2244 extern int inode_init_always(struct super_block *, struct inode *); 2245 extern void inode_init_once(struct inode *); 2246 extern void address_space_init_once(struct address_space *mapping); 2247 extern void ihold(struct inode * inode); 2248 extern void iput(struct inode *); 2249 extern struct inode * igrab(struct inode *); 2250 extern ino_t iunique(struct super_block *, ino_t); 2251 extern int inode_needs_sync(struct inode *inode); 2252 extern int generic_delete_inode(struct inode *inode); 2253 extern int generic_drop_inode(struct inode *inode); 2254 2255 extern struct inode *ilookup5_nowait(struct super_block *sb, 2256 unsigned long hashval, int (*test)(struct inode *, void *), 2257 void *data); 2258 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval, 2259 int (*test)(struct inode *, void *), void *data); 2260 extern struct inode *ilookup(struct super_block *sb, unsigned long ino); 2261 2262 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *); 2263 extern struct inode * iget_locked(struct super_block *, unsigned long); 2264 extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *); 2265 extern int insert_inode_locked(struct inode *); 2266 extern void unlock_new_inode(struct inode *); 2267 extern unsigned int get_next_ino(void); 2268 2269 extern void __iget(struct inode * inode); 2270 extern void iget_failed(struct inode *); 2271 extern void end_writeback(struct inode *); 2272 extern void __destroy_inode(struct inode *); 2273 extern struct inode *new_inode(struct super_block *); 2274 extern void free_inode_nonrcu(struct inode *inode); 2275 extern int should_remove_suid(struct dentry *); 2276 extern int file_remove_suid(struct file *); 2277 2278 extern void __insert_inode_hash(struct inode *, unsigned long hashval); 2279 extern void remove_inode_hash(struct inode *); 2280 static inline void insert_inode_hash(struct inode *inode) 2281 { 2282 __insert_inode_hash(inode, inode->i_ino); 2283 } 2284 extern void inode_sb_list_add(struct inode *inode); 2285 2286 #ifdef CONFIG_BLOCK 2287 extern void submit_bio(int, struct bio *); 2288 extern int bdev_read_only(struct block_device *); 2289 #endif 2290 extern int set_blocksize(struct block_device *, int); 2291 extern int sb_set_blocksize(struct super_block *, int); 2292 extern int sb_min_blocksize(struct super_block *, int); 2293 2294 extern int generic_file_mmap(struct file *, struct vm_area_struct *); 2295 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *); 2296 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size); 2297 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk); 2298 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t); 2299 extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, 2300 loff_t *); 2301 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t); 2302 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *, 2303 unsigned long *, loff_t, loff_t *, size_t, size_t); 2304 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *, 2305 unsigned long, loff_t, loff_t *, size_t, ssize_t); 2306 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos); 2307 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos); 2308 extern int generic_segment_checks(const struct iovec *iov, 2309 unsigned long *nr_segs, size_t *count, int access_flags); 2310 2311 /* fs/block_dev.c */ 2312 extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, 2313 unsigned long nr_segs, loff_t pos); 2314 extern int blkdev_fsync(struct file *filp, int datasync); 2315 2316 /* fs/splice.c */ 2317 extern ssize_t generic_file_splice_read(struct file *, loff_t *, 2318 struct pipe_inode_info *, size_t, unsigned int); 2319 extern ssize_t default_file_splice_read(struct file *, loff_t *, 2320 struct pipe_inode_info *, size_t, unsigned int); 2321 extern ssize_t generic_file_splice_write(struct pipe_inode_info *, 2322 struct file *, loff_t *, size_t, unsigned int); 2323 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, 2324 struct file *out, loff_t *, size_t len, unsigned int flags); 2325 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, 2326 size_t len, unsigned int flags); 2327 2328 extern void 2329 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping); 2330 extern loff_t noop_llseek(struct file *file, loff_t offset, int origin); 2331 extern loff_t no_llseek(struct file *file, loff_t offset, int origin); 2332 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin); 2333 extern loff_t generic_file_llseek_unlocked(struct file *file, loff_t offset, 2334 int origin); 2335 extern int generic_file_open(struct inode * inode, struct file * filp); 2336 extern int nonseekable_open(struct inode * inode, struct file * filp); 2337 2338 #ifdef CONFIG_FS_XIP 2339 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len, 2340 loff_t *ppos); 2341 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma); 2342 extern ssize_t xip_file_write(struct file *filp, const char __user *buf, 2343 size_t len, loff_t *ppos); 2344 extern int xip_truncate_page(struct address_space *mapping, loff_t from); 2345 #else 2346 static inline int xip_truncate_page(struct address_space *mapping, loff_t from) 2347 { 2348 return 0; 2349 } 2350 #endif 2351 2352 #ifdef CONFIG_BLOCK 2353 typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode, 2354 loff_t file_offset); 2355 2356 enum { 2357 /* need locking between buffered and direct access */ 2358 DIO_LOCKING = 0x01, 2359 2360 /* filesystem does not support filling holes */ 2361 DIO_SKIP_HOLES = 0x02, 2362 }; 2363 2364 void dio_end_io(struct bio *bio, int error); 2365 2366 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, 2367 struct block_device *bdev, const struct iovec *iov, loff_t offset, 2368 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io, 2369 dio_submit_t submit_io, int flags); 2370 2371 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb, 2372 struct inode *inode, struct block_device *bdev, const struct iovec *iov, 2373 loff_t offset, unsigned long nr_segs, get_block_t get_block, 2374 dio_iodone_t end_io) 2375 { 2376 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset, 2377 nr_segs, get_block, end_io, NULL, 2378 DIO_LOCKING | DIO_SKIP_HOLES); 2379 } 2380 #endif 2381 2382 extern const struct file_operations generic_ro_fops; 2383 2384 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m)) 2385 2386 extern int vfs_readlink(struct dentry *, char __user *, int, const char *); 2387 extern int vfs_follow_link(struct nameidata *, const char *); 2388 extern int page_readlink(struct dentry *, char __user *, int); 2389 extern void *page_follow_link_light(struct dentry *, struct nameidata *); 2390 extern void page_put_link(struct dentry *, struct nameidata *, void *); 2391 extern int __page_symlink(struct inode *inode, const char *symname, int len, 2392 int nofs); 2393 extern int page_symlink(struct inode *inode, const char *symname, int len); 2394 extern const struct inode_operations page_symlink_inode_operations; 2395 extern int generic_readlink(struct dentry *, char __user *, int); 2396 extern void generic_fillattr(struct inode *, struct kstat *); 2397 extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *); 2398 void __inode_add_bytes(struct inode *inode, loff_t bytes); 2399 void inode_add_bytes(struct inode *inode, loff_t bytes); 2400 void inode_sub_bytes(struct inode *inode, loff_t bytes); 2401 loff_t inode_get_bytes(struct inode *inode); 2402 void inode_set_bytes(struct inode *inode, loff_t bytes); 2403 2404 extern int vfs_readdir(struct file *, filldir_t, void *); 2405 2406 extern int vfs_stat(const char __user *, struct kstat *); 2407 extern int vfs_lstat(const char __user *, struct kstat *); 2408 extern int vfs_fstat(unsigned int, struct kstat *); 2409 extern int vfs_fstatat(int , const char __user *, struct kstat *, int); 2410 2411 extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, 2412 unsigned long arg); 2413 extern int __generic_block_fiemap(struct inode *inode, 2414 struct fiemap_extent_info *fieinfo, 2415 loff_t start, loff_t len, 2416 get_block_t *get_block); 2417 extern int generic_block_fiemap(struct inode *inode, 2418 struct fiemap_extent_info *fieinfo, u64 start, 2419 u64 len, get_block_t *get_block); 2420 2421 extern void get_filesystem(struct file_system_type *fs); 2422 extern void put_filesystem(struct file_system_type *fs); 2423 extern struct file_system_type *get_fs_type(const char *name); 2424 extern struct super_block *get_super(struct block_device *); 2425 extern struct super_block *get_active_super(struct block_device *bdev); 2426 extern struct super_block *user_get_super(dev_t); 2427 extern void drop_super(struct super_block *sb); 2428 extern void iterate_supers(void (*)(struct super_block *, void *), void *); 2429 2430 extern int dcache_dir_open(struct inode *, struct file *); 2431 extern int dcache_dir_close(struct inode *, struct file *); 2432 extern loff_t dcache_dir_lseek(struct file *, loff_t, int); 2433 extern int dcache_readdir(struct file *, void *, filldir_t); 2434 extern int simple_setattr(struct dentry *, struct iattr *); 2435 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *); 2436 extern int simple_statfs(struct dentry *, struct kstatfs *); 2437 extern int simple_link(struct dentry *, struct inode *, struct dentry *); 2438 extern int simple_unlink(struct inode *, struct dentry *); 2439 extern int simple_rmdir(struct inode *, struct dentry *); 2440 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); 2441 extern int noop_fsync(struct file *, int); 2442 extern int simple_empty(struct dentry *); 2443 extern int simple_readpage(struct file *file, struct page *page); 2444 extern int simple_write_begin(struct file *file, struct address_space *mapping, 2445 loff_t pos, unsigned len, unsigned flags, 2446 struct page **pagep, void **fsdata); 2447 extern int simple_write_end(struct file *file, struct address_space *mapping, 2448 loff_t pos, unsigned len, unsigned copied, 2449 struct page *page, void *fsdata); 2450 2451 extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *); 2452 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *); 2453 extern const struct file_operations simple_dir_operations; 2454 extern const struct inode_operations simple_dir_inode_operations; 2455 struct tree_descr { char *name; const struct file_operations *ops; int mode; }; 2456 struct dentry *d_alloc_name(struct dentry *, const char *); 2457 extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *); 2458 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count); 2459 extern void simple_release_fs(struct vfsmount **mount, int *count); 2460 2461 extern ssize_t simple_read_from_buffer(void __user *to, size_t count, 2462 loff_t *ppos, const void *from, size_t available); 2463 extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos, 2464 const void __user *from, size_t count); 2465 2466 extern int generic_file_fsync(struct file *, int); 2467 2468 extern int generic_check_addressable(unsigned, u64); 2469 2470 #ifdef CONFIG_MIGRATION 2471 extern int buffer_migrate_page(struct address_space *, 2472 struct page *, struct page *); 2473 #else 2474 #define buffer_migrate_page NULL 2475 #endif 2476 2477 extern int inode_change_ok(const struct inode *, struct iattr *); 2478 extern int inode_newsize_ok(const struct inode *, loff_t offset); 2479 extern void setattr_copy(struct inode *inode, const struct iattr *attr); 2480 2481 extern void file_update_time(struct file *file); 2482 2483 extern int generic_show_options(struct seq_file *m, struct vfsmount *mnt); 2484 extern void save_mount_options(struct super_block *sb, char *options); 2485 extern void replace_mount_options(struct super_block *sb, char *options); 2486 2487 static inline ino_t parent_ino(struct dentry *dentry) 2488 { 2489 ino_t res; 2490 2491 /* 2492 * Don't strictly need d_lock here? If the parent ino could change 2493 * then surely we'd have a deeper race in the caller? 2494 */ 2495 spin_lock(&dentry->d_lock); 2496 res = dentry->d_parent->d_inode->i_ino; 2497 spin_unlock(&dentry->d_lock); 2498 return res; 2499 } 2500 2501 /* Transaction based IO helpers */ 2502 2503 /* 2504 * An argresp is stored in an allocated page and holds the 2505 * size of the argument or response, along with its content 2506 */ 2507 struct simple_transaction_argresp { 2508 ssize_t size; 2509 char data[0]; 2510 }; 2511 2512 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp)) 2513 2514 char *simple_transaction_get(struct file *file, const char __user *buf, 2515 size_t size); 2516 ssize_t simple_transaction_read(struct file *file, char __user *buf, 2517 size_t size, loff_t *pos); 2518 int simple_transaction_release(struct inode *inode, struct file *file); 2519 2520 void simple_transaction_set(struct file *file, size_t n); 2521 2522 /* 2523 * simple attribute files 2524 * 2525 * These attributes behave similar to those in sysfs: 2526 * 2527 * Writing to an attribute immediately sets a value, an open file can be 2528 * written to multiple times. 2529 * 2530 * Reading from an attribute creates a buffer from the value that might get 2531 * read with multiple read calls. When the attribute has been read 2532 * completely, no further read calls are possible until the file is opened 2533 * again. 2534 * 2535 * All attributes contain a text representation of a numeric value 2536 * that are accessed with the get() and set() functions. 2537 */ 2538 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \ 2539 static int __fops ## _open(struct inode *inode, struct file *file) \ 2540 { \ 2541 __simple_attr_check_format(__fmt, 0ull); \ 2542 return simple_attr_open(inode, file, __get, __set, __fmt); \ 2543 } \ 2544 static const struct file_operations __fops = { \ 2545 .owner = THIS_MODULE, \ 2546 .open = __fops ## _open, \ 2547 .release = simple_attr_release, \ 2548 .read = simple_attr_read, \ 2549 .write = simple_attr_write, \ 2550 .llseek = generic_file_llseek, \ 2551 }; 2552 2553 static inline void __attribute__((format(printf, 1, 2))) 2554 __simple_attr_check_format(const char *fmt, ...) 2555 { 2556 /* don't do anything, just let the compiler check the arguments; */ 2557 } 2558 2559 int simple_attr_open(struct inode *inode, struct file *file, 2560 int (*get)(void *, u64 *), int (*set)(void *, u64), 2561 const char *fmt); 2562 int simple_attr_release(struct inode *inode, struct file *file); 2563 ssize_t simple_attr_read(struct file *file, char __user *buf, 2564 size_t len, loff_t *ppos); 2565 ssize_t simple_attr_write(struct file *file, const char __user *buf, 2566 size_t len, loff_t *ppos); 2567 2568 struct ctl_table; 2569 int proc_nr_files(struct ctl_table *table, int write, 2570 void __user *buffer, size_t *lenp, loff_t *ppos); 2571 int proc_nr_dentry(struct ctl_table *table, int write, 2572 void __user *buffer, size_t *lenp, loff_t *ppos); 2573 int proc_nr_inodes(struct ctl_table *table, int write, 2574 void __user *buffer, size_t *lenp, loff_t *ppos); 2575 int __init get_filesystem_list(char *buf); 2576 2577 #define __FMODE_EXEC ((__force int) FMODE_EXEC) 2578 #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY) 2579 2580 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) 2581 #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \ 2582 (flag & __FMODE_NONOTIFY))) 2583 2584 #endif /* __KERNEL__ */ 2585 #endif /* _LINUX_FS_H */ 2586