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 12 /* 13 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change 14 * the file limit at runtime and only root can increase the per-process 15 * nr_file rlimit, so it's safe to set up a ridiculously high absolute 16 * upper limit on files-per-process. 17 * 18 * Some programs (notably those using select()) may have to be 19 * recompiled to take full advantage of the new limits.. 20 */ 21 22 /* Fixed constants first: */ 23 #undef NR_OPEN 24 #define INR_OPEN 1024 /* Initial setting for nfile rlimits */ 25 26 #define BLOCK_SIZE_BITS 10 27 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS) 28 29 #define SEEK_SET 0 /* seek relative to beginning of file */ 30 #define SEEK_CUR 1 /* seek relative to current file position */ 31 #define SEEK_END 2 /* seek relative to end of file */ 32 #define SEEK_MAX SEEK_END 33 34 /* And dynamically-tunable limits and defaults: */ 35 struct files_stat_struct { 36 int nr_files; /* read only */ 37 int nr_free_files; /* read only */ 38 int max_files; /* tunable */ 39 }; 40 41 struct inodes_stat_t { 42 int nr_inodes; 43 int nr_unused; 44 int dummy[5]; /* padding for sysctl ABI compatibility */ 45 }; 46 47 48 #define NR_FILE 8192 /* this can well be larger on a larger system */ 49 50 #define MAY_EXEC 1 51 #define MAY_WRITE 2 52 #define MAY_READ 4 53 #define MAY_APPEND 8 54 #define MAY_ACCESS 16 55 #define MAY_OPEN 32 56 57 /* 58 * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond 59 * to O_WRONLY and O_RDWR via the strange trick in __dentry_open() 60 */ 61 62 /* file is open for reading */ 63 #define FMODE_READ ((fmode_t)1) 64 /* file is open for writing */ 65 #define FMODE_WRITE ((fmode_t)2) 66 /* file is seekable */ 67 #define FMODE_LSEEK ((fmode_t)4) 68 /* file can be accessed using pread */ 69 #define FMODE_PREAD ((fmode_t)8) 70 /* file can be accessed using pwrite */ 71 #define FMODE_PWRITE ((fmode_t)16) 72 /* File is opened for execution with sys_execve / sys_uselib */ 73 #define FMODE_EXEC ((fmode_t)32) 74 /* File is opened with O_NDELAY (only set for block devices) */ 75 #define FMODE_NDELAY ((fmode_t)64) 76 /* File is opened with O_EXCL (only set for block devices) */ 77 #define FMODE_EXCL ((fmode_t)128) 78 /* File is opened using open(.., 3, ..) and is writeable only for ioctls 79 (specialy hack for floppy.c) */ 80 #define FMODE_WRITE_IOCTL ((fmode_t)256) 81 82 /* 83 * Don't update ctime and mtime. 84 * 85 * Currently a special hack for the XFS open_by_handle ioctl, but we'll 86 * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon. 87 */ 88 #define FMODE_NOCMTIME ((fmode_t)2048) 89 90 /* Expect random access pattern */ 91 #define FMODE_RANDOM ((fmode_t)4096) 92 93 /* 94 * The below are the various read and write types that we support. Some of 95 * them include behavioral modifiers that send information down to the 96 * block layer and IO scheduler. Terminology: 97 * 98 * The block layer uses device plugging to defer IO a little bit, in 99 * the hope that we will see more IO very shortly. This increases 100 * coalescing of adjacent IO and thus reduces the number of IOs we 101 * have to send to the device. It also allows for better queuing, 102 * if the IO isn't mergeable. If the caller is going to be waiting 103 * for the IO, then he must ensure that the device is unplugged so 104 * that the IO is dispatched to the driver. 105 * 106 * All IO is handled async in Linux. This is fine for background 107 * writes, but for reads or writes that someone waits for completion 108 * on, we want to notify the block layer and IO scheduler so that they 109 * know about it. That allows them to make better scheduling 110 * decisions. So when the below references 'sync' and 'async', it 111 * is referencing this priority hint. 112 * 113 * With that in mind, the available types are: 114 * 115 * READ A normal read operation. Device will be plugged. 116 * READ_SYNC A synchronous read. Device is not plugged, caller can 117 * immediately wait on this read without caring about 118 * unplugging. 119 * READA Used for read-ahead operations. Lower priority, and the 120 * block layer could (in theory) choose to ignore this 121 * request if it runs into resource problems. 122 * WRITE A normal async write. Device will be plugged. 123 * SWRITE Like WRITE, but a special case for ll_rw_block() that 124 * tells it to lock the buffer first. Normally a buffer 125 * must be locked before doing IO. 126 * WRITE_SYNC_PLUG Synchronous write. Identical to WRITE, but passes down 127 * the hint that someone will be waiting on this IO 128 * shortly. The device must still be unplugged explicitly, 129 * WRITE_SYNC_PLUG does not do this as we could be 130 * submitting more writes before we actually wait on any 131 * of them. 132 * WRITE_SYNC Like WRITE_SYNC_PLUG, but also unplugs the device 133 * immediately after submission. The write equivalent 134 * of READ_SYNC. 135 * WRITE_ODIRECT Special case write for O_DIRECT only. 136 * SWRITE_SYNC 137 * SWRITE_SYNC_PLUG Like WRITE_SYNC/WRITE_SYNC_PLUG, but locks the buffer. 138 * See SWRITE. 139 * WRITE_BARRIER Like WRITE, but tells the block layer that all 140 * previously submitted writes must be safely on storage 141 * before this one is started. Also guarantees that when 142 * this write is complete, it itself is also safely on 143 * storage. Prevents reordering of writes on both sides 144 * of this IO. 145 * 146 */ 147 #define RW_MASK 1 148 #define RWA_MASK 2 149 #define READ 0 150 #define WRITE 1 151 #define READA 2 /* read-ahead - don't block if no resources */ 152 #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */ 153 #define READ_SYNC (READ | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG)) 154 #define READ_META (READ | (1 << BIO_RW_META)) 155 #define WRITE_SYNC_PLUG (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE)) 156 #define WRITE_SYNC (WRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG)) 157 #define WRITE_ODIRECT (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG)) 158 #define SWRITE_SYNC_PLUG \ 159 (SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE)) 160 #define SWRITE_SYNC (SWRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG)) 161 #define WRITE_BARRIER (WRITE | (1 << BIO_RW_BARRIER)) 162 163 /* 164 * These aren't really reads or writes, they pass down information about 165 * parts of device that are now unused by the file system. 166 */ 167 #define DISCARD_NOBARRIER (WRITE | (1 << BIO_RW_DISCARD)) 168 #define DISCARD_BARRIER (DISCARD_NOBARRIER | (1 << BIO_RW_BARRIER)) 169 170 #define SEL_IN 1 171 #define SEL_OUT 2 172 #define SEL_EX 4 173 174 /* public flags for file_system_type */ 175 #define FS_REQUIRES_DEV 1 176 #define FS_BINARY_MOUNTDATA 2 177 #define FS_HAS_SUBTYPE 4 178 #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */ 179 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() 180 * during rename() internally. 181 */ 182 183 /* 184 * These are the fs-independent mount-flags: up to 32 flags are supported 185 */ 186 #define MS_RDONLY 1 /* Mount read-only */ 187 #define MS_NOSUID 2 /* Ignore suid and sgid bits */ 188 #define MS_NODEV 4 /* Disallow access to device special files */ 189 #define MS_NOEXEC 8 /* Disallow program execution */ 190 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */ 191 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */ 192 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */ 193 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */ 194 #define MS_NOATIME 1024 /* Do not update access times. */ 195 #define MS_NODIRATIME 2048 /* Do not update directory access times */ 196 #define MS_BIND 4096 197 #define MS_MOVE 8192 198 #define MS_REC 16384 199 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence. 200 MS_VERBOSE is deprecated. */ 201 #define MS_SILENT 32768 202 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */ 203 #define MS_UNBINDABLE (1<<17) /* change to unbindable */ 204 #define MS_PRIVATE (1<<18) /* change to private */ 205 #define MS_SLAVE (1<<19) /* change to slave */ 206 #define MS_SHARED (1<<20) /* change to shared */ 207 #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */ 208 #define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */ 209 #define MS_I_VERSION (1<<23) /* Update inode I_version field */ 210 #define MS_STRICTATIME (1<<24) /* Always perform atime updates */ 211 #define MS_ACTIVE (1<<30) 212 #define MS_NOUSER (1<<31) 213 214 /* 215 * Superblock flags that can be altered by MS_REMOUNT 216 */ 217 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION) 218 219 /* 220 * Old magic mount flag and mask 221 */ 222 #define MS_MGC_VAL 0xC0ED0000 223 #define MS_MGC_MSK 0xffff0000 224 225 /* Inode flags - they have nothing to superblock flags now */ 226 227 #define S_SYNC 1 /* Writes are synced at once */ 228 #define S_NOATIME 2 /* Do not update access times */ 229 #define S_APPEND 4 /* Append-only file */ 230 #define S_IMMUTABLE 8 /* Immutable file */ 231 #define S_DEAD 16 /* removed, but still open directory */ 232 #define S_NOQUOTA 32 /* Inode is not counted to quota */ 233 #define S_DIRSYNC 64 /* Directory modifications are synchronous */ 234 #define S_NOCMTIME 128 /* Do not update file c/mtime */ 235 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */ 236 #define S_PRIVATE 512 /* Inode is fs-internal */ 237 238 /* 239 * Note that nosuid etc flags are inode-specific: setting some file-system 240 * flags just means all the inodes inherit those flags by default. It might be 241 * possible to override it selectively if you really wanted to with some 242 * ioctl() that is not currently implemented. 243 * 244 * Exception: MS_RDONLY is always applied to the entire file system. 245 * 246 * Unfortunately, it is possible to change a filesystems flags with it mounted 247 * with files in use. This means that all of the inodes will not have their 248 * i_flags updated. Hence, i_flags no longer inherit the superblock mount 249 * flags, so these have to be checked separately. -- rmk (at) arm.uk.linux.org 250 */ 251 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg)) 252 253 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY) 254 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \ 255 ((inode)->i_flags & S_SYNC)) 256 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \ 257 ((inode)->i_flags & (S_SYNC|S_DIRSYNC))) 258 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK) 259 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME) 260 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION) 261 262 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA) 263 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND) 264 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE) 265 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL) 266 267 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD) 268 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME) 269 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE) 270 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE) 271 272 /* the read-only stuff doesn't really belong here, but any other place is 273 probably as bad and I don't want to create yet another include file. */ 274 275 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */ 276 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */ 277 #define BLKRRPART _IO(0x12,95) /* re-read partition table */ 278 #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */ 279 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */ 280 #define BLKRASET _IO(0x12,98) /* set read ahead for block device */ 281 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */ 282 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */ 283 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */ 284 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */ 285 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */ 286 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */ 287 #if 0 288 #define BLKPG _IO(0x12,105)/* See blkpg.h */ 289 290 /* Some people are morons. Do not use sizeof! */ 291 292 #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */ 293 #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */ 294 /* This was here just to show that the number is taken - 295 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */ 296 #endif 297 /* A jump here: 108-111 have been used for various private purposes. */ 298 #define BLKBSZGET _IOR(0x12,112,size_t) 299 #define BLKBSZSET _IOW(0x12,113,size_t) 300 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ 301 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup) 302 #define BLKTRACESTART _IO(0x12,116) 303 #define BLKTRACESTOP _IO(0x12,117) 304 #define BLKTRACETEARDOWN _IO(0x12,118) 305 #define BLKDISCARD _IO(0x12,119) 306 #define BLKIOMIN _IO(0x12,120) 307 #define BLKIOOPT _IO(0x12,121) 308 #define BLKALIGNOFF _IO(0x12,122) 309 #define BLKPBSZGET _IO(0x12,123) 310 311 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ 312 #define FIBMAP _IO(0x00,1) /* bmap access */ 313 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */ 314 #define FIFREEZE _IOWR('X', 119, int) /* Freeze */ 315 #define FITHAW _IOWR('X', 120, int) /* Thaw */ 316 317 #define FS_IOC_GETFLAGS _IOR('f', 1, long) 318 #define FS_IOC_SETFLAGS _IOW('f', 2, long) 319 #define FS_IOC_GETVERSION _IOR('v', 1, long) 320 #define FS_IOC_SETVERSION _IOW('v', 2, long) 321 #define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap) 322 #define FS_IOC32_GETFLAGS _IOR('f', 1, int) 323 #define FS_IOC32_SETFLAGS _IOW('f', 2, int) 324 #define FS_IOC32_GETVERSION _IOR('v', 1, int) 325 #define FS_IOC32_SETVERSION _IOW('v', 2, int) 326 327 /* 328 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS) 329 */ 330 #define FS_SECRM_FL 0x00000001 /* Secure deletion */ 331 #define FS_UNRM_FL 0x00000002 /* Undelete */ 332 #define FS_COMPR_FL 0x00000004 /* Compress file */ 333 #define FS_SYNC_FL 0x00000008 /* Synchronous updates */ 334 #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */ 335 #define FS_APPEND_FL 0x00000020 /* writes to file may only append */ 336 #define FS_NODUMP_FL 0x00000040 /* do not dump file */ 337 #define FS_NOATIME_FL 0x00000080 /* do not update atime */ 338 /* Reserved for compression usage... */ 339 #define FS_DIRTY_FL 0x00000100 340 #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 341 #define FS_NOCOMP_FL 0x00000400 /* Don't compress */ 342 #define FS_ECOMPR_FL 0x00000800 /* Compression error */ 343 /* End compression flags --- maybe not all used */ 344 #define FS_BTREE_FL 0x00001000 /* btree format dir */ 345 #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */ 346 #define FS_IMAGIC_FL 0x00002000 /* AFS directory */ 347 #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */ 348 #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 349 #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */ 350 #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 351 #define FS_EXTENT_FL 0x00080000 /* Extents */ 352 #define FS_DIRECTIO_FL 0x00100000 /* Use direct i/o */ 353 #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 354 355 #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */ 356 #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */ 357 358 359 #define SYNC_FILE_RANGE_WAIT_BEFORE 1 360 #define SYNC_FILE_RANGE_WRITE 2 361 #define SYNC_FILE_RANGE_WAIT_AFTER 4 362 363 #endif /* _LINUX_FS_H */ 364
