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