1 /* 2 * ext4.h 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/include/linux/minix_fs.h 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 */ 15 16 #ifndef _EXT4_H 17 #define _EXT4_H 18 19 #include <linux/types.h> 20 #include <linux/blkdev.h> 21 #include <linux/magic.h> 22 #include <linux/jbd2.h> 23 #include <linux/quota.h> 24 #include <linux/rwsem.h> 25 #include <linux/rbtree.h> 26 #include <linux/seqlock.h> 27 #include <linux/mutex.h> 28 #include <linux/timer.h> 29 #include <linux/wait.h> 30 #include <linux/blockgroup_lock.h> 31 #include <linux/percpu_counter.h> 32 #ifdef __KERNEL__ 33 #include <linux/compat.h> 34 #endif 35 36 /* 37 * The fourth extended filesystem constants/structures 38 */ 39 40 /* 41 * Define EXT4FS_DEBUG to produce debug messages 42 */ 43 #undef EXT4FS_DEBUG 44 45 /* 46 * Debug code 47 */ 48 #ifdef EXT4FS_DEBUG 49 #define ext4_debug(f, a...) \ 50 do { \ 51 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:", \ 52 __FILE__, __LINE__, __func__); \ 53 printk(KERN_DEBUG f, ## a); \ 54 } while (0) 55 #else 56 #define ext4_debug(f, a...) do {} while (0) 57 #endif 58 59 #define EXT4_ERROR_INODE(inode, fmt, a...) \ 60 ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a) 61 62 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...) \ 63 ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a) 64 65 #define EXT4_ERROR_FILE(file, block, fmt, a...) \ 66 ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a) 67 68 /* data type for block offset of block group */ 69 typedef int ext4_grpblk_t; 70 71 /* data type for filesystem-wide blocks number */ 72 typedef unsigned long long ext4_fsblk_t; 73 74 /* data type for file logical block number */ 75 typedef __u32 ext4_lblk_t; 76 77 /* data type for block group number */ 78 typedef unsigned int ext4_group_t; 79 80 /* 81 * Flags used in mballoc's allocation_context flags field. 82 * 83 * Also used to show what's going on for debugging purposes when the 84 * flag field is exported via the traceport interface 85 */ 86 87 /* prefer goal again. length */ 88 #define EXT4_MB_HINT_MERGE 0x0001 89 /* blocks already reserved */ 90 #define EXT4_MB_HINT_RESERVED 0x0002 91 /* metadata is being allocated */ 92 #define EXT4_MB_HINT_METADATA 0x0004 93 /* first blocks in the file */ 94 #define EXT4_MB_HINT_FIRST 0x0008 95 /* search for the best chunk */ 96 #define EXT4_MB_HINT_BEST 0x0010 97 /* data is being allocated */ 98 #define EXT4_MB_HINT_DATA 0x0020 99 /* don't preallocate (for tails) */ 100 #define EXT4_MB_HINT_NOPREALLOC 0x0040 101 /* allocate for locality group */ 102 #define EXT4_MB_HINT_GROUP_ALLOC 0x0080 103 /* allocate goal blocks or none */ 104 #define EXT4_MB_HINT_GOAL_ONLY 0x0100 105 /* goal is meaningful */ 106 #define EXT4_MB_HINT_TRY_GOAL 0x0200 107 /* blocks already pre-reserved by delayed allocation */ 108 #define EXT4_MB_DELALLOC_RESERVED 0x0400 109 /* We are doing stream allocation */ 110 #define EXT4_MB_STREAM_ALLOC 0x0800 111 112 113 struct ext4_allocation_request { 114 /* target inode for block we're allocating */ 115 struct inode *inode; 116 /* how many blocks we want to allocate */ 117 unsigned int len; 118 /* logical block in target inode */ 119 ext4_lblk_t logical; 120 /* the closest logical allocated block to the left */ 121 ext4_lblk_t lleft; 122 /* the closest logical allocated block to the right */ 123 ext4_lblk_t lright; 124 /* phys. target (a hint) */ 125 ext4_fsblk_t goal; 126 /* phys. block for the closest logical allocated block to the left */ 127 ext4_fsblk_t pleft; 128 /* phys. block for the closest logical allocated block to the right */ 129 ext4_fsblk_t pright; 130 /* flags. see above EXT4_MB_HINT_* */ 131 unsigned int flags; 132 }; 133 134 /* 135 * Logical to physical block mapping, used by ext4_map_blocks() 136 * 137 * This structure is used to pass requests into ext4_map_blocks() as 138 * well as to store the information returned by ext4_map_blocks(). It 139 * takes less room on the stack than a struct buffer_head. 140 */ 141 #define EXT4_MAP_NEW (1 << BH_New) 142 #define EXT4_MAP_MAPPED (1 << BH_Mapped) 143 #define EXT4_MAP_UNWRITTEN (1 << BH_Unwritten) 144 #define EXT4_MAP_BOUNDARY (1 << BH_Boundary) 145 #define EXT4_MAP_UNINIT (1 << BH_Uninit) 146 #define EXT4_MAP_FLAGS (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\ 147 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\ 148 EXT4_MAP_UNINIT) 149 150 struct ext4_map_blocks { 151 ext4_fsblk_t m_pblk; 152 ext4_lblk_t m_lblk; 153 unsigned int m_len; 154 unsigned int m_flags; 155 }; 156 157 /* 158 * For delayed allocation tracking 159 */ 160 struct mpage_da_data { 161 struct inode *inode; 162 sector_t b_blocknr; /* start block number of extent */ 163 size_t b_size; /* size of extent */ 164 unsigned long b_state; /* state of the extent */ 165 unsigned long first_page, next_page; /* extent of pages */ 166 struct writeback_control *wbc; 167 int io_done; 168 int pages_written; 169 int retval; 170 }; 171 172 /* 173 * Flags for ext4_io_end->flags 174 */ 175 #define EXT4_IO_END_UNWRITTEN 0x0001 176 #define EXT4_IO_END_ERROR 0x0002 177 178 struct ext4_io_page { 179 struct page *p_page; 180 atomic_t p_count; 181 }; 182 183 #define MAX_IO_PAGES 128 184 185 typedef struct ext4_io_end { 186 struct list_head list; /* per-file finished IO list */ 187 struct inode *inode; /* file being written to */ 188 unsigned int flag; /* unwritten or not */ 189 struct page *page; /* page struct for buffer write */ 190 loff_t offset; /* offset in the file */ 191 ssize_t size; /* size of the extent */ 192 struct work_struct work; /* data work queue */ 193 struct kiocb *iocb; /* iocb struct for AIO */ 194 int result; /* error value for AIO */ 195 int num_io_pages; 196 struct ext4_io_page *pages[MAX_IO_PAGES]; 197 } ext4_io_end_t; 198 199 struct ext4_io_submit { 200 int io_op; 201 struct bio *io_bio; 202 ext4_io_end_t *io_end; 203 struct ext4_io_page *io_page; 204 sector_t io_next_block; 205 }; 206 207 /* 208 * Special inodes numbers 209 */ 210 #define EXT4_BAD_INO 1 /* Bad blocks inode */ 211 #define EXT4_ROOT_INO 2 /* Root inode */ 212 #define EXT4_BOOT_LOADER_INO 5 /* Boot loader inode */ 213 #define EXT4_UNDEL_DIR_INO 6 /* Undelete directory inode */ 214 #define EXT4_RESIZE_INO 7 /* Reserved group descriptors inode */ 215 #define EXT4_JOURNAL_INO 8 /* Journal inode */ 216 217 /* First non-reserved inode for old ext4 filesystems */ 218 #define EXT4_GOOD_OLD_FIRST_INO 11 219 220 /* 221 * Maximal count of links to a file 222 */ 223 #define EXT4_LINK_MAX 65000 224 225 /* 226 * Macro-instructions used to manage several block sizes 227 */ 228 #define EXT4_MIN_BLOCK_SIZE 1024 229 #define EXT4_MAX_BLOCK_SIZE 65536 230 #define EXT4_MIN_BLOCK_LOG_SIZE 10 231 #define EXT4_MAX_BLOCK_LOG_SIZE 16 232 #ifdef __KERNEL__ 233 # define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize) 234 #else 235 # define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size) 236 #endif 237 #define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof(__u32)) 238 #ifdef __KERNEL__ 239 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits) 240 #else 241 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10) 242 #endif 243 #ifdef __KERNEL__ 244 #define EXT4_ADDR_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_addr_per_block_bits) 245 #define EXT4_INODE_SIZE(s) (EXT4_SB(s)->s_inode_size) 246 #define EXT4_FIRST_INO(s) (EXT4_SB(s)->s_first_ino) 247 #else 248 #define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \ 249 EXT4_GOOD_OLD_INODE_SIZE : \ 250 (s)->s_inode_size) 251 #define EXT4_FIRST_INO(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \ 252 EXT4_GOOD_OLD_FIRST_INO : \ 253 (s)->s_first_ino) 254 #endif 255 #define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits))) 256 257 /* 258 * Structure of a blocks group descriptor 259 */ 260 struct ext4_group_desc 261 { 262 __le32 bg_block_bitmap_lo; /* Blocks bitmap block */ 263 __le32 bg_inode_bitmap_lo; /* Inodes bitmap block */ 264 __le32 bg_inode_table_lo; /* Inodes table block */ 265 __le16 bg_free_blocks_count_lo;/* Free blocks count */ 266 __le16 bg_free_inodes_count_lo;/* Free inodes count */ 267 __le16 bg_used_dirs_count_lo; /* Directories count */ 268 __le16 bg_flags; /* EXT4_BG_flags (INODE_UNINIT, etc) */ 269 __u32 bg_reserved[2]; /* Likely block/inode bitmap checksum */ 270 __le16 bg_itable_unused_lo; /* Unused inodes count */ 271 __le16 bg_checksum; /* crc16(sb_uuid+group+desc) */ 272 __le32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */ 273 __le32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */ 274 __le32 bg_inode_table_hi; /* Inodes table block MSB */ 275 __le16 bg_free_blocks_count_hi;/* Free blocks count MSB */ 276 __le16 bg_free_inodes_count_hi;/* Free inodes count MSB */ 277 __le16 bg_used_dirs_count_hi; /* Directories count MSB */ 278 __le16 bg_itable_unused_hi; /* Unused inodes count MSB */ 279 __u32 bg_reserved2[3]; 280 }; 281 282 /* 283 * Structure of a flex block group info 284 */ 285 286 struct flex_groups { 287 atomic_t free_inodes; 288 atomic_t free_blocks; 289 atomic_t used_dirs; 290 }; 291 292 #define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */ 293 #define EXT4_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */ 294 #define EXT4_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */ 295 296 /* 297 * Macro-instructions used to manage group descriptors 298 */ 299 #define EXT4_MIN_DESC_SIZE 32 300 #define EXT4_MIN_DESC_SIZE_64BIT 64 301 #define EXT4_MAX_DESC_SIZE EXT4_MIN_BLOCK_SIZE 302 #define EXT4_DESC_SIZE(s) (EXT4_SB(s)->s_desc_size) 303 #ifdef __KERNEL__ 304 # define EXT4_BLOCKS_PER_GROUP(s) (EXT4_SB(s)->s_blocks_per_group) 305 # define EXT4_DESC_PER_BLOCK(s) (EXT4_SB(s)->s_desc_per_block) 306 # define EXT4_INODES_PER_GROUP(s) (EXT4_SB(s)->s_inodes_per_group) 307 # define EXT4_DESC_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_desc_per_block_bits) 308 #else 309 # define EXT4_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group) 310 # define EXT4_DESC_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s)) 311 # define EXT4_INODES_PER_GROUP(s) ((s)->s_inodes_per_group) 312 #endif 313 314 /* 315 * Constants relative to the data blocks 316 */ 317 #define EXT4_NDIR_BLOCKS 12 318 #define EXT4_IND_BLOCK EXT4_NDIR_BLOCKS 319 #define EXT4_DIND_BLOCK (EXT4_IND_BLOCK + 1) 320 #define EXT4_TIND_BLOCK (EXT4_DIND_BLOCK + 1) 321 #define EXT4_N_BLOCKS (EXT4_TIND_BLOCK + 1) 322 323 /* 324 * Inode flags 325 */ 326 #define EXT4_SECRM_FL 0x00000001 /* Secure deletion */ 327 #define EXT4_UNRM_FL 0x00000002 /* Undelete */ 328 #define EXT4_COMPR_FL 0x00000004 /* Compress file */ 329 #define EXT4_SYNC_FL 0x00000008 /* Synchronous updates */ 330 #define EXT4_IMMUTABLE_FL 0x00000010 /* Immutable file */ 331 #define EXT4_APPEND_FL 0x00000020 /* writes to file may only append */ 332 #define EXT4_NODUMP_FL 0x00000040 /* do not dump file */ 333 #define EXT4_NOATIME_FL 0x00000080 /* do not update atime */ 334 /* Reserved for compression usage... */ 335 #define EXT4_DIRTY_FL 0x00000100 336 #define EXT4_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 337 #define EXT4_NOCOMPR_FL 0x00000400 /* Don't compress */ 338 #define EXT4_ECOMPR_FL 0x00000800 /* Compression error */ 339 /* End compression flags --- maybe not all used */ 340 #define EXT4_INDEX_FL 0x00001000 /* hash-indexed directory */ 341 #define EXT4_IMAGIC_FL 0x00002000 /* AFS directory */ 342 #define EXT4_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */ 343 #define EXT4_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 344 #define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */ 345 #define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 346 #define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */ 347 #define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */ 348 #define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */ 349 #define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */ 350 #define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */ 351 352 #define EXT4_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */ 353 #define EXT4_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */ 354 355 /* Flags that should be inherited by new inodes from their parent. */ 356 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\ 357 EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\ 358 EXT4_NODUMP_FL | EXT4_NOATIME_FL |\ 359 EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\ 360 EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL) 361 362 /* Flags that are appropriate for regular files (all but dir-specific ones). */ 363 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL)) 364 365 /* Flags that are appropriate for non-directories/regular files. */ 366 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL) 367 368 /* Mask out flags that are inappropriate for the given type of inode. */ 369 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags) 370 { 371 if (S_ISDIR(mode)) 372 return flags; 373 else if (S_ISREG(mode)) 374 return flags & EXT4_REG_FLMASK; 375 else 376 return flags & EXT4_OTHER_FLMASK; 377 } 378 379 /* 380 * Inode flags used for atomic set/get 381 */ 382 enum { 383 EXT4_INODE_SECRM = 0, /* Secure deletion */ 384 EXT4_INODE_UNRM = 1, /* Undelete */ 385 EXT4_INODE_COMPR = 2, /* Compress file */ 386 EXT4_INODE_SYNC = 3, /* Synchronous updates */ 387 EXT4_INODE_IMMUTABLE = 4, /* Immutable file */ 388 EXT4_INODE_APPEND = 5, /* writes to file may only append */ 389 EXT4_INODE_NODUMP = 6, /* do not dump file */ 390 EXT4_INODE_NOATIME = 7, /* do not update atime */ 391 /* Reserved for compression usage... */ 392 EXT4_INODE_DIRTY = 8, 393 EXT4_INODE_COMPRBLK = 9, /* One or more compressed clusters */ 394 EXT4_INODE_NOCOMPR = 10, /* Don't compress */ 395 EXT4_INODE_ECOMPR = 11, /* Compression error */ 396 /* End compression flags --- maybe not all used */ 397 EXT4_INODE_INDEX = 12, /* hash-indexed directory */ 398 EXT4_INODE_IMAGIC = 13, /* AFS directory */ 399 EXT4_INODE_JOURNAL_DATA = 14, /* file data should be journaled */ 400 EXT4_INODE_NOTAIL = 15, /* file tail should not be merged */ 401 EXT4_INODE_DIRSYNC = 16, /* dirsync behaviour (directories only) */ 402 EXT4_INODE_TOPDIR = 17, /* Top of directory hierarchies*/ 403 EXT4_INODE_HUGE_FILE = 18, /* Set to each huge file */ 404 EXT4_INODE_EXTENTS = 19, /* Inode uses extents */ 405 EXT4_INODE_EA_INODE = 21, /* Inode used for large EA */ 406 EXT4_INODE_EOFBLOCKS = 22, /* Blocks allocated beyond EOF */ 407 EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */ 408 }; 409 410 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG)) 411 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \ 412 printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \ 413 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); } 414 415 /* 416 * Since it's pretty easy to mix up bit numbers and hex values, and we 417 * can't do a compile-time test for ENUM values, we use a run-time 418 * test to make sure that EXT4_XXX_FL is consistent with respect to 419 * EXT4_INODE_XXX. If all is well the printk and BUG_ON will all drop 420 * out so it won't cost any extra space in the compiled kernel image. 421 * But it's important that these values are the same, since we are 422 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL 423 * must be consistent with the values of FS_XXX_FL defined in 424 * include/linux/fs.h and the on-disk values found in ext2, ext3, and 425 * ext4 filesystems, and of course the values defined in e2fsprogs. 426 * 427 * It's not paranoia if the Murphy's Law really *is* out to get you. :-) 428 */ 429 static inline void ext4_check_flag_values(void) 430 { 431 CHECK_FLAG_VALUE(SECRM); 432 CHECK_FLAG_VALUE(UNRM); 433 CHECK_FLAG_VALUE(COMPR); 434 CHECK_FLAG_VALUE(SYNC); 435 CHECK_FLAG_VALUE(IMMUTABLE); 436 CHECK_FLAG_VALUE(APPEND); 437 CHECK_FLAG_VALUE(NODUMP); 438 CHECK_FLAG_VALUE(NOATIME); 439 CHECK_FLAG_VALUE(DIRTY); 440 CHECK_FLAG_VALUE(COMPRBLK); 441 CHECK_FLAG_VALUE(NOCOMPR); 442 CHECK_FLAG_VALUE(ECOMPR); 443 CHECK_FLAG_VALUE(INDEX); 444 CHECK_FLAG_VALUE(IMAGIC); 445 CHECK_FLAG_VALUE(JOURNAL_DATA); 446 CHECK_FLAG_VALUE(NOTAIL); 447 CHECK_FLAG_VALUE(DIRSYNC); 448 CHECK_FLAG_VALUE(TOPDIR); 449 CHECK_FLAG_VALUE(HUGE_FILE); 450 CHECK_FLAG_VALUE(EXTENTS); 451 CHECK_FLAG_VALUE(EA_INODE); 452 CHECK_FLAG_VALUE(EOFBLOCKS); 453 CHECK_FLAG_VALUE(RESERVED); 454 } 455 456 /* Used to pass group descriptor data when online resize is done */ 457 struct ext4_new_group_input { 458 __u32 group; /* Group number for this data */ 459 __u64 block_bitmap; /* Absolute block number of block bitmap */ 460 __u64 inode_bitmap; /* Absolute block number of inode bitmap */ 461 __u64 inode_table; /* Absolute block number of inode table start */ 462 __u32 blocks_count; /* Total number of blocks in this group */ 463 __u16 reserved_blocks; /* Number of reserved blocks in this group */ 464 __u16 unused; 465 }; 466 467 #if defined(__KERNEL__) && defined(CONFIG_COMPAT) 468 struct compat_ext4_new_group_input { 469 u32 group; 470 compat_u64 block_bitmap; 471 compat_u64 inode_bitmap; 472 compat_u64 inode_table; 473 u32 blocks_count; 474 u16 reserved_blocks; 475 u16 unused; 476 }; 477 #endif 478 479 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */ 480 struct ext4_new_group_data { 481 __u32 group; 482 __u64 block_bitmap; 483 __u64 inode_bitmap; 484 __u64 inode_table; 485 __u32 blocks_count; 486 __u16 reserved_blocks; 487 __u16 unused; 488 __u32 free_blocks_count; 489 }; 490 491 /* 492 * Flags used by ext4_map_blocks() 493 */ 494 /* Allocate any needed blocks and/or convert an unitialized 495 extent to be an initialized ext4 */ 496 #define EXT4_GET_BLOCKS_CREATE 0x0001 497 /* Request the creation of an unitialized extent */ 498 #define EXT4_GET_BLOCKS_UNINIT_EXT 0x0002 499 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT (EXT4_GET_BLOCKS_UNINIT_EXT|\ 500 EXT4_GET_BLOCKS_CREATE) 501 /* Caller is from the delayed allocation writeout path, 502 so set the magic i_delalloc_reserve_flag after taking the 503 inode allocation semaphore for */ 504 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE 0x0004 505 /* caller is from the direct IO path, request to creation of an 506 unitialized extents if not allocated, split the uninitialized 507 extent if blocks has been preallocated already*/ 508 #define EXT4_GET_BLOCKS_PRE_IO 0x0008 509 #define EXT4_GET_BLOCKS_CONVERT 0x0010 510 #define EXT4_GET_BLOCKS_IO_CREATE_EXT (EXT4_GET_BLOCKS_PRE_IO|\ 511 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT) 512 /* Convert extent to initialized after IO complete */ 513 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT (EXT4_GET_BLOCKS_CONVERT|\ 514 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT) 515 516 /* 517 * Flags used by ext4_free_blocks 518 */ 519 #define EXT4_FREE_BLOCKS_METADATA 0x0001 520 #define EXT4_FREE_BLOCKS_FORGET 0x0002 521 #define EXT4_FREE_BLOCKS_VALIDATED 0x0004 522 523 /* 524 * ioctl commands 525 */ 526 #define EXT4_IOC_GETFLAGS FS_IOC_GETFLAGS 527 #define EXT4_IOC_SETFLAGS FS_IOC_SETFLAGS 528 #define EXT4_IOC_GETVERSION _IOR('f', 3, long) 529 #define EXT4_IOC_SETVERSION _IOW('f', 4, long) 530 #define EXT4_IOC_GETVERSION_OLD FS_IOC_GETVERSION 531 #define EXT4_IOC_SETVERSION_OLD FS_IOC_SETVERSION 532 #ifdef CONFIG_JBD2_DEBUG 533 #define EXT4_IOC_WAIT_FOR_READONLY _IOR('f', 99, long) 534 #endif 535 #define EXT4_IOC_GETRSVSZ _IOR('f', 5, long) 536 #define EXT4_IOC_SETRSVSZ _IOW('f', 6, long) 537 #define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) 538 #define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input) 539 #define EXT4_IOC_MIGRATE _IO('f', 9) 540 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */ 541 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */ 542 #define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12) 543 #define EXT4_IOC_MOVE_EXT _IOWR('f', 15, struct move_extent) 544 545 #if defined(__KERNEL__) && defined(CONFIG_COMPAT) 546 /* 547 * ioctl commands in 32 bit emulation 548 */ 549 #define EXT4_IOC32_GETFLAGS FS_IOC32_GETFLAGS 550 #define EXT4_IOC32_SETFLAGS FS_IOC32_SETFLAGS 551 #define EXT4_IOC32_GETVERSION _IOR('f', 3, int) 552 #define EXT4_IOC32_SETVERSION _IOW('f', 4, int) 553 #define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int) 554 #define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int) 555 #define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int) 556 #define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input) 557 #ifdef CONFIG_JBD2_DEBUG 558 #define EXT4_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int) 559 #endif 560 #define EXT4_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION 561 #define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION 562 #endif 563 564 /* Max physical block we can address w/o extents */ 565 #define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF 566 567 /* 568 * Structure of an inode on the disk 569 */ 570 struct ext4_inode { 571 __le16 i_mode; /* File mode */ 572 __le16 i_uid; /* Low 16 bits of Owner Uid */ 573 __le32 i_size_lo; /* Size in bytes */ 574 __le32 i_atime; /* Access time */ 575 __le32 i_ctime; /* Inode Change time */ 576 __le32 i_mtime; /* Modification time */ 577 __le32 i_dtime; /* Deletion Time */ 578 __le16 i_gid; /* Low 16 bits of Group Id */ 579 __le16 i_links_count; /* Links count */ 580 __le32 i_blocks_lo; /* Blocks count */ 581 __le32 i_flags; /* File flags */ 582 union { 583 struct { 584 __le32 l_i_version; 585 } linux1; 586 struct { 587 __u32 h_i_translator; 588 } hurd1; 589 struct { 590 __u32 m_i_reserved1; 591 } masix1; 592 } osd1; /* OS dependent 1 */ 593 __le32 i_block[EXT4_N_BLOCKS];/* Pointers to blocks */ 594 __le32 i_generation; /* File version (for NFS) */ 595 __le32 i_file_acl_lo; /* File ACL */ 596 __le32 i_size_high; 597 __le32 i_obso_faddr; /* Obsoleted fragment address */ 598 union { 599 struct { 600 __le16 l_i_blocks_high; /* were l_i_reserved1 */ 601 __le16 l_i_file_acl_high; 602 __le16 l_i_uid_high; /* these 2 fields */ 603 __le16 l_i_gid_high; /* were reserved2[0] */ 604 __u32 l_i_reserved2; 605 } linux2; 606 struct { 607 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */ 608 __u16 h_i_mode_high; 609 __u16 h_i_uid_high; 610 __u16 h_i_gid_high; 611 __u32 h_i_author; 612 } hurd2; 613 struct { 614 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */ 615 __le16 m_i_file_acl_high; 616 __u32 m_i_reserved2[2]; 617 } masix2; 618 } osd2; /* OS dependent 2 */ 619 __le16 i_extra_isize; 620 __le16 i_pad1; 621 __le32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */ 622 __le32 i_mtime_extra; /* extra Modification time(nsec << 2 | epoch) */ 623 __le32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */ 624 __le32 i_crtime; /* File Creation time */ 625 __le32 i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */ 626 __le32 i_version_hi; /* high 32 bits for 64-bit version */ 627 }; 628 629 struct move_extent { 630 __u32 reserved; /* should be zero */ 631 __u32 donor_fd; /* donor file descriptor */ 632 __u64 orig_start; /* logical start offset in block for orig */ 633 __u64 donor_start; /* logical start offset in block for donor */ 634 __u64 len; /* block length to be moved */ 635 __u64 moved_len; /* moved block length */ 636 }; 637 638 #define EXT4_EPOCH_BITS 2 639 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1) 640 #define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS) 641 642 /* 643 * Extended fields will fit into an inode if the filesystem was formatted 644 * with large inodes (-I 256 or larger) and there are not currently any EAs 645 * consuming all of the available space. For new inodes we always reserve 646 * enough space for the kernel's known extended fields, but for inodes 647 * created with an old kernel this might not have been the case. None of 648 * the extended inode fields is critical for correct filesystem operation. 649 * This macro checks if a certain field fits in the inode. Note that 650 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize 651 */ 652 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field) \ 653 ((offsetof(typeof(*ext4_inode), field) + \ 654 sizeof((ext4_inode)->field)) \ 655 <= (EXT4_GOOD_OLD_INODE_SIZE + \ 656 (einode)->i_extra_isize)) \ 657 658 static inline __le32 ext4_encode_extra_time(struct timespec *time) 659 { 660 return cpu_to_le32((sizeof(time->tv_sec) > 4 ? 661 (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) | 662 ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK)); 663 } 664 665 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra) 666 { 667 if (sizeof(time->tv_sec) > 4) 668 time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) 669 << 32; 670 time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS; 671 } 672 673 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode) \ 674 do { \ 675 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \ 676 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \ 677 (raw_inode)->xtime ## _extra = \ 678 ext4_encode_extra_time(&(inode)->xtime); \ 679 } while (0) 680 681 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \ 682 do { \ 683 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \ 684 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec); \ 685 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \ 686 (raw_inode)->xtime ## _extra = \ 687 ext4_encode_extra_time(&(einode)->xtime); \ 688 } while (0) 689 690 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode) \ 691 do { \ 692 (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime); \ 693 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \ 694 ext4_decode_extra_time(&(inode)->xtime, \ 695 raw_inode->xtime ## _extra); \ 696 else \ 697 (inode)->xtime.tv_nsec = 0; \ 698 } while (0) 699 700 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode) \ 701 do { \ 702 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \ 703 (einode)->xtime.tv_sec = \ 704 (signed)le32_to_cpu((raw_inode)->xtime); \ 705 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \ 706 ext4_decode_extra_time(&(einode)->xtime, \ 707 raw_inode->xtime ## _extra); \ 708 else \ 709 (einode)->xtime.tv_nsec = 0; \ 710 } while (0) 711 712 #define i_disk_version osd1.linux1.l_i_version 713 714 #if defined(__KERNEL__) || defined(__linux__) 715 #define i_reserved1 osd1.linux1.l_i_reserved1 716 #define i_file_acl_high osd2.linux2.l_i_file_acl_high 717 #define i_blocks_high osd2.linux2.l_i_blocks_high 718 #define i_uid_low i_uid 719 #define i_gid_low i_gid 720 #define i_uid_high osd2.linux2.l_i_uid_high 721 #define i_gid_high osd2.linux2.l_i_gid_high 722 #define i_reserved2 osd2.linux2.l_i_reserved2 723 724 #elif defined(__GNU__) 725 726 #define i_translator osd1.hurd1.h_i_translator 727 #define i_uid_high osd2.hurd2.h_i_uid_high 728 #define i_gid_high osd2.hurd2.h_i_gid_high 729 #define i_author osd2.hurd2.h_i_author 730 731 #elif defined(__masix__) 732 733 #define i_reserved1 osd1.masix1.m_i_reserved1 734 #define i_file_acl_high osd2.masix2.m_i_file_acl_high 735 #define i_reserved2 osd2.masix2.m_i_reserved2 736 737 #endif /* defined(__KERNEL__) || defined(__linux__) */ 738 739 /* 740 * storage for cached extent 741 * If ec_len == 0, then the cache is invalid. 742 * If ec_start == 0, then the cache represents a gap (null mapping) 743 */ 744 struct ext4_ext_cache { 745 ext4_fsblk_t ec_start; 746 ext4_lblk_t ec_block; 747 __u32 ec_len; /* must be 32bit to return holes */ 748 }; 749 750 /* 751 * fourth extended file system inode data in memory 752 */ 753 struct ext4_inode_info { 754 __le32 i_data[15]; /* unconverted */ 755 __u32 i_dtime; 756 ext4_fsblk_t i_file_acl; 757 758 /* 759 * i_block_group is the number of the block group which contains 760 * this file's inode. Constant across the lifetime of the inode, 761 * it is ued for making block allocation decisions - we try to 762 * place a file's data blocks near its inode block, and new inodes 763 * near to their parent directory's inode. 764 */ 765 ext4_group_t i_block_group; 766 ext4_lblk_t i_dir_start_lookup; 767 #if (BITS_PER_LONG < 64) 768 unsigned long i_state_flags; /* Dynamic state flags */ 769 #endif 770 unsigned long i_flags; 771 772 #ifdef CONFIG_EXT4_FS_XATTR 773 /* 774 * Extended attributes can be read independently of the main file 775 * data. Taking i_mutex even when reading would cause contention 776 * between readers of EAs and writers of regular file data, so 777 * instead we synchronize on xattr_sem when reading or changing 778 * EAs. 779 */ 780 struct rw_semaphore xattr_sem; 781 #endif 782 783 struct list_head i_orphan; /* unlinked but open inodes */ 784 785 /* 786 * i_disksize keeps track of what the inode size is ON DISK, not 787 * in memory. During truncate, i_size is set to the new size by 788 * the VFS prior to calling ext4_truncate(), but the filesystem won't 789 * set i_disksize to 0 until the truncate is actually under way. 790 * 791 * The intent is that i_disksize always represents the blocks which 792 * are used by this file. This allows recovery to restart truncate 793 * on orphans if we crash during truncate. We actually write i_disksize 794 * into the on-disk inode when writing inodes out, instead of i_size. 795 * 796 * The only time when i_disksize and i_size may be different is when 797 * a truncate is in progress. The only things which change i_disksize 798 * are ext4_get_block (growth) and ext4_truncate (shrinkth). 799 */ 800 loff_t i_disksize; 801 802 /* 803 * i_data_sem is for serialising ext4_truncate() against 804 * ext4_getblock(). In the 2.4 ext2 design, great chunks of inode's 805 * data tree are chopped off during truncate. We can't do that in 806 * ext4 because whenever we perform intermediate commits during 807 * truncate, the inode and all the metadata blocks *must* be in a 808 * consistent state which allows truncation of the orphans to restart 809 * during recovery. Hence we must fix the get_block-vs-truncate race 810 * by other means, so we have i_data_sem. 811 */ 812 struct rw_semaphore i_data_sem; 813 struct inode vfs_inode; 814 struct jbd2_inode *jinode; 815 816 struct ext4_ext_cache i_cached_extent; 817 /* 818 * File creation time. Its function is same as that of 819 * struct timespec i_{a,c,m}time in the generic inode. 820 */ 821 struct timespec i_crtime; 822 823 /* mballoc */ 824 struct list_head i_prealloc_list; 825 spinlock_t i_prealloc_lock; 826 827 /* ialloc */ 828 ext4_group_t i_last_alloc_group; 829 830 /* allocation reservation info for delalloc */ 831 unsigned int i_reserved_data_blocks; 832 unsigned int i_reserved_meta_blocks; 833 unsigned int i_allocated_meta_blocks; 834 ext4_lblk_t i_da_metadata_calc_last_lblock; 835 int i_da_metadata_calc_len; 836 837 /* on-disk additional length */ 838 __u16 i_extra_isize; 839 840 #ifdef CONFIG_QUOTA 841 /* quota space reservation, managed internally by quota code */ 842 qsize_t i_reserved_quota; 843 #endif 844 845 /* completed IOs that might need unwritten extents handling */ 846 struct list_head i_completed_io_list; 847 spinlock_t i_completed_io_lock; 848 atomic_t i_ioend_count; /* Number of outstanding io_end structs */ 849 /* current io_end structure for async DIO write*/ 850 ext4_io_end_t *cur_aio_dio; 851 852 spinlock_t i_block_reservation_lock; 853 854 /* 855 * Transactions that contain inode's metadata needed to complete 856 * fsync and fdatasync, respectively. 857 */ 858 tid_t i_sync_tid; 859 tid_t i_datasync_tid; 860 }; 861 862 /* 863 * File system states 864 */ 865 #define EXT4_VALID_FS 0x0001 /* Unmounted cleanly */ 866 #define EXT4_ERROR_FS 0x0002 /* Errors detected */ 867 #define EXT4_ORPHAN_FS 0x0004 /* Orphans being recovered */ 868 869 /* 870 * Misc. filesystem flags 871 */ 872 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */ 873 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */ 874 #define EXT2_FLAGS_TEST_FILESYS 0x0004 /* to test development code */ 875 876 /* 877 * Mount flags 878 */ 879 #define EXT4_MOUNT_OLDALLOC 0x00002 /* Don't use the new Orlov allocator */ 880 #define EXT4_MOUNT_GRPID 0x00004 /* Create files with directory's group */ 881 #define EXT4_MOUNT_DEBUG 0x00008 /* Some debugging messages */ 882 #define EXT4_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */ 883 #define EXT4_MOUNT_ERRORS_RO 0x00020 /* Remount fs ro on errors */ 884 #define EXT4_MOUNT_ERRORS_PANIC 0x00040 /* Panic on errors */ 885 #define EXT4_MOUNT_MINIX_DF 0x00080 /* Mimics the Minix statfs */ 886 #define EXT4_MOUNT_NOLOAD 0x00100 /* Don't use existing journal*/ 887 #define EXT4_MOUNT_DATA_FLAGS 0x00C00 /* Mode for data writes: */ 888 #define EXT4_MOUNT_JOURNAL_DATA 0x00400 /* Write data to journal */ 889 #define EXT4_MOUNT_ORDERED_DATA 0x00800 /* Flush data before commit */ 890 #define EXT4_MOUNT_WRITEBACK_DATA 0x00C00 /* No data ordering */ 891 #define EXT4_MOUNT_UPDATE_JOURNAL 0x01000 /* Update the journal format */ 892 #define EXT4_MOUNT_NO_UID32 0x02000 /* Disable 32-bit UIDs */ 893 #define EXT4_MOUNT_XATTR_USER 0x04000 /* Extended user attributes */ 894 #define EXT4_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */ 895 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */ 896 #define EXT4_MOUNT_BARRIER 0x20000 /* Use block barriers */ 897 #define EXT4_MOUNT_QUOTA 0x80000 /* Some quota option set */ 898 #define EXT4_MOUNT_USRQUOTA 0x100000 /* "old" user quota */ 899 #define EXT4_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */ 900 #define EXT4_MOUNT_DIOREAD_NOLOCK 0x400000 /* Enable support for dio read nolocking */ 901 #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */ 902 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */ 903 #define EXT4_MOUNT_I_VERSION 0x2000000 /* i_version support */ 904 #define EXT4_MOUNT_MBLK_IO_SUBMIT 0x4000000 /* multi-block io submits */ 905 #define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */ 906 #define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */ 907 #define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */ 908 #define EXT4_MOUNT_DISCARD 0x40000000 /* Issue DISCARD requests */ 909 #define EXT4_MOUNT_INIT_INODE_TABLE 0x80000000 /* Initialize uninitialized itables */ 910 911 #define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \ 912 ~EXT4_MOUNT_##opt 913 #define set_opt(sb, opt) EXT4_SB(sb)->s_mount_opt |= \ 914 EXT4_MOUNT_##opt 915 #define test_opt(sb, opt) (EXT4_SB(sb)->s_mount_opt & \ 916 EXT4_MOUNT_##opt) 917 918 #define clear_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 &= \ 919 ~EXT4_MOUNT2_##opt 920 #define set_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 |= \ 921 EXT4_MOUNT2_##opt 922 #define test_opt2(sb, opt) (EXT4_SB(sb)->s_mount_opt2 & \ 923 EXT4_MOUNT2_##opt) 924 925 #define ext4_set_bit ext2_set_bit 926 #define ext4_set_bit_atomic ext2_set_bit_atomic 927 #define ext4_clear_bit ext2_clear_bit 928 #define ext4_clear_bit_atomic ext2_clear_bit_atomic 929 #define ext4_test_bit ext2_test_bit 930 #define ext4_find_first_zero_bit ext2_find_first_zero_bit 931 #define ext4_find_next_zero_bit ext2_find_next_zero_bit 932 #define ext4_find_next_bit ext2_find_next_bit 933 934 /* 935 * Maximal mount counts between two filesystem checks 936 */ 937 #define EXT4_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 938 #define EXT4_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 939 940 /* 941 * Behaviour when detecting errors 942 */ 943 #define EXT4_ERRORS_CONTINUE 1 /* Continue execution */ 944 #define EXT4_ERRORS_RO 2 /* Remount fs read-only */ 945 #define EXT4_ERRORS_PANIC 3 /* Panic */ 946 #define EXT4_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE 947 948 /* 949 * Structure of the super block 950 */ 951 struct ext4_super_block { 952 /*00*/ __le32 s_inodes_count; /* Inodes count */ 953 __le32 s_blocks_count_lo; /* Blocks count */ 954 __le32 s_r_blocks_count_lo; /* Reserved blocks count */ 955 __le32 s_free_blocks_count_lo; /* Free blocks count */ 956 /*10*/ __le32 s_free_inodes_count; /* Free inodes count */ 957 __le32 s_first_data_block; /* First Data Block */ 958 __le32 s_log_block_size; /* Block size */ 959 __le32 s_obso_log_frag_size; /* Obsoleted fragment size */ 960 /*20*/ __le32 s_blocks_per_group; /* # Blocks per group */ 961 __le32 s_obso_frags_per_group; /* Obsoleted fragments per group */ 962 __le32 s_inodes_per_group; /* # Inodes per group */ 963 __le32 s_mtime; /* Mount time */ 964 /*30*/ __le32 s_wtime; /* Write time */ 965 __le16 s_mnt_count; /* Mount count */ 966 __le16 s_max_mnt_count; /* Maximal mount count */ 967 __le16 s_magic; /* Magic signature */ 968 __le16 s_state; /* File system state */ 969 __le16 s_errors; /* Behaviour when detecting errors */ 970 __le16 s_minor_rev_level; /* minor revision level */ 971 /*40*/ __le32 s_lastcheck; /* time of last check */ 972 __le32 s_checkinterval; /* max. time between checks */ 973 __le32 s_creator_os; /* OS */ 974 __le32 s_rev_level; /* Revision level */ 975 /*50*/ __le16 s_def_resuid; /* Default uid for reserved blocks */ 976 __le16 s_def_resgid; /* Default gid for reserved blocks */ 977 /* 978 * These fields are for EXT4_DYNAMIC_REV superblocks only. 979 * 980 * Note: the difference between the compatible feature set and 981 * the incompatible feature set is that if there is a bit set 982 * in the incompatible feature set that the kernel doesn't 983 * know about, it should refuse to mount the filesystem. 984 * 985 * e2fsck's requirements are more strict; if it doesn't know 986 * about a feature in either the compatible or incompatible 987 * feature set, it must abort and not try to meddle with 988 * things it doesn't understand... 989 */ 990 __le32 s_first_ino; /* First non-reserved inode */ 991 __le16 s_inode_size; /* size of inode structure */ 992 __le16 s_block_group_nr; /* block group # of this superblock */ 993 __le32 s_feature_compat; /* compatible feature set */ 994 /*60*/ __le32 s_feature_incompat; /* incompatible feature set */ 995 __le32 s_feature_ro_compat; /* readonly-compatible feature set */ 996 /*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */ 997 /*78*/ char s_volume_name[16]; /* volume name */ 998 /*88*/ char s_last_mounted[64]; /* directory where last mounted */ 999 /*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */ 1000 /* 1001 * Performance hints. Directory preallocation should only 1002 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on. 1003 */ 1004 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 1005 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 1006 __le16 s_reserved_gdt_blocks; /* Per group desc for online growth */ 1007 /* 1008 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set. 1009 */ 1010 /*D0*/ __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 1011 /*E0*/ __le32 s_journal_inum; /* inode number of journal file */ 1012 __le32 s_journal_dev; /* device number of journal file */ 1013 __le32 s_last_orphan; /* start of list of inodes to delete */ 1014 __le32 s_hash_seed[4]; /* HTREE hash seed */ 1015 __u8 s_def_hash_version; /* Default hash version to use */ 1016 __u8 s_jnl_backup_type; 1017 __le16 s_desc_size; /* size of group descriptor */ 1018 /*100*/ __le32 s_default_mount_opts; 1019 __le32 s_first_meta_bg; /* First metablock block group */ 1020 __le32 s_mkfs_time; /* When the filesystem was created */ 1021 __le32 s_jnl_blocks[17]; /* Backup of the journal inode */ 1022 /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */ 1023 /*150*/ __le32 s_blocks_count_hi; /* Blocks count */ 1024 __le32 s_r_blocks_count_hi; /* Reserved blocks count */ 1025 __le32 s_free_blocks_count_hi; /* Free blocks count */ 1026 __le16 s_min_extra_isize; /* All inodes have at least # bytes */ 1027 __le16 s_want_extra_isize; /* New inodes should reserve # bytes */ 1028 __le32 s_flags; /* Miscellaneous flags */ 1029 __le16 s_raid_stride; /* RAID stride */ 1030 __le16 s_mmp_interval; /* # seconds to wait in MMP checking */ 1031 __le64 s_mmp_block; /* Block for multi-mount protection */ 1032 __le32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/ 1033 __u8 s_log_groups_per_flex; /* FLEX_BG group size */ 1034 __u8 s_reserved_char_pad; 1035 __le16 s_reserved_pad; 1036 __le64 s_kbytes_written; /* nr of lifetime kilobytes written */ 1037 __le32 s_snapshot_inum; /* Inode number of active snapshot */ 1038 __le32 s_snapshot_id; /* sequential ID of active snapshot */ 1039 __le64 s_snapshot_r_blocks_count; /* reserved blocks for active 1040 snapshot's future use */ 1041 __le32 s_snapshot_list; /* inode number of the head of the 1042 on-disk snapshot list */ 1043 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count) 1044 __le32 s_error_count; /* number of fs errors */ 1045 __le32 s_first_error_time; /* first time an error happened */ 1046 __le32 s_first_error_ino; /* inode involved in first error */ 1047 __le64 s_first_error_block; /* block involved of first error */ 1048 __u8 s_first_error_func[32]; /* function where the error happened */ 1049 __le32 s_first_error_line; /* line number where error happened */ 1050 __le32 s_last_error_time; /* most recent time of an error */ 1051 __le32 s_last_error_ino; /* inode involved in last error */ 1052 __le32 s_last_error_line; /* line number where error happened */ 1053 __le64 s_last_error_block; /* block involved of last error */ 1054 __u8 s_last_error_func[32]; /* function where the error happened */ 1055 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts) 1056 __u8 s_mount_opts[64]; 1057 __le32 s_reserved[112]; /* Padding to the end of the block */ 1058 }; 1059 1060 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START) 1061 1062 #ifdef __KERNEL__ 1063 1064 /* 1065 * run-time mount flags 1066 */ 1067 #define EXT4_MF_MNTDIR_SAMPLED 0x0001 1068 #define EXT4_MF_FS_ABORTED 0x0002 /* Fatal error detected */ 1069 1070 /* 1071 * fourth extended-fs super-block data in memory 1072 */ 1073 struct ext4_sb_info { 1074 unsigned long s_desc_size; /* Size of a group descriptor in bytes */ 1075 unsigned long s_inodes_per_block;/* Number of inodes per block */ 1076 unsigned long s_blocks_per_group;/* Number of blocks in a group */ 1077 unsigned long s_inodes_per_group;/* Number of inodes in a group */ 1078 unsigned long s_itb_per_group; /* Number of inode table blocks per group */ 1079 unsigned long s_gdb_count; /* Number of group descriptor blocks */ 1080 unsigned long s_desc_per_block; /* Number of group descriptors per block */ 1081 ext4_group_t s_groups_count; /* Number of groups in the fs */ 1082 ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */ 1083 unsigned long s_overhead_last; /* Last calculated overhead */ 1084 unsigned long s_blocks_last; /* Last seen block count */ 1085 loff_t s_bitmap_maxbytes; /* max bytes for bitmap files */ 1086 struct buffer_head * s_sbh; /* Buffer containing the super block */ 1087 struct ext4_super_block *s_es; /* Pointer to the super block in the buffer */ 1088 struct buffer_head **s_group_desc; 1089 unsigned int s_mount_opt; 1090 unsigned int s_mount_opt2; 1091 unsigned int s_mount_flags; 1092 ext4_fsblk_t s_sb_block; 1093 uid_t s_resuid; 1094 gid_t s_resgid; 1095 unsigned short s_mount_state; 1096 unsigned short s_pad; 1097 int s_addr_per_block_bits; 1098 int s_desc_per_block_bits; 1099 int s_inode_size; 1100 int s_first_ino; 1101 unsigned int s_inode_readahead_blks; 1102 unsigned int s_inode_goal; 1103 spinlock_t s_next_gen_lock; 1104 u32 s_next_generation; 1105 u32 s_hash_seed[4]; 1106 int s_def_hash_version; 1107 int s_hash_unsigned; /* 3 if hash should be signed, 0 if not */ 1108 struct percpu_counter s_freeblocks_counter; 1109 struct percpu_counter s_freeinodes_counter; 1110 struct percpu_counter s_dirs_counter; 1111 struct percpu_counter s_dirtyblocks_counter; 1112 struct blockgroup_lock *s_blockgroup_lock; 1113 struct proc_dir_entry *s_proc; 1114 struct kobject s_kobj; 1115 struct completion s_kobj_unregister; 1116 1117 /* Journaling */ 1118 struct journal_s *s_journal; 1119 struct list_head s_orphan; 1120 struct mutex s_orphan_lock; 1121 struct mutex s_resize_lock; 1122 unsigned long s_commit_interval; 1123 u32 s_max_batch_time; 1124 u32 s_min_batch_time; 1125 struct block_device *journal_bdev; 1126 #ifdef CONFIG_JBD2_DEBUG 1127 struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */ 1128 wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */ 1129 #endif 1130 #ifdef CONFIG_QUOTA 1131 char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */ 1132 int s_jquota_fmt; /* Format of quota to use */ 1133 #endif 1134 unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */ 1135 struct rb_root system_blks; 1136 1137 #ifdef EXTENTS_STATS 1138 /* ext4 extents stats */ 1139 unsigned long s_ext_min; 1140 unsigned long s_ext_max; 1141 unsigned long s_depth_max; 1142 spinlock_t s_ext_stats_lock; 1143 unsigned long s_ext_blocks; 1144 unsigned long s_ext_extents; 1145 #endif 1146 1147 /* for buddy allocator */ 1148 struct ext4_group_info ***s_group_info; 1149 struct inode *s_buddy_cache; 1150 spinlock_t s_md_lock; 1151 unsigned short *s_mb_offsets; 1152 unsigned int *s_mb_maxs; 1153 1154 /* tunables */ 1155 unsigned long s_stripe; 1156 unsigned int s_mb_stream_request; 1157 unsigned int s_mb_max_to_scan; 1158 unsigned int s_mb_min_to_scan; 1159 unsigned int s_mb_stats; 1160 unsigned int s_mb_order2_reqs; 1161 unsigned int s_mb_group_prealloc; 1162 unsigned int s_max_writeback_mb_bump; 1163 /* where last allocation was done - for stream allocation */ 1164 unsigned long s_mb_last_group; 1165 unsigned long s_mb_last_start; 1166 1167 /* stats for buddy allocator */ 1168 atomic_t s_bal_reqs; /* number of reqs with len > 1 */ 1169 atomic_t s_bal_success; /* we found long enough chunks */ 1170 atomic_t s_bal_allocated; /* in blocks */ 1171 atomic_t s_bal_ex_scanned; /* total extents scanned */ 1172 atomic_t s_bal_goals; /* goal hits */ 1173 atomic_t s_bal_breaks; /* too long searches */ 1174 atomic_t s_bal_2orders; /* 2^order hits */ 1175 spinlock_t s_bal_lock; 1176 unsigned long s_mb_buddies_generated; 1177 unsigned long long s_mb_generation_time; 1178 atomic_t s_mb_lost_chunks; 1179 atomic_t s_mb_preallocated; 1180 atomic_t s_mb_discarded; 1181 atomic_t s_lock_busy; 1182 1183 /* locality groups */ 1184 struct ext4_locality_group __percpu *s_locality_groups; 1185 1186 /* for write statistics */ 1187 unsigned long s_sectors_written_start; 1188 u64 s_kbytes_written; 1189 1190 unsigned int s_log_groups_per_flex; 1191 struct flex_groups *s_flex_groups; 1192 1193 /* workqueue for dio unwritten */ 1194 struct workqueue_struct *dio_unwritten_wq; 1195 1196 /* timer for periodic error stats printing */ 1197 struct timer_list s_err_report; 1198 1199 /* Lazy inode table initialization info */ 1200 struct ext4_li_request *s_li_request; 1201 /* Wait multiplier for lazy initialization thread */ 1202 unsigned int s_li_wait_mult; 1203 }; 1204 1205 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) 1206 { 1207 return sb->s_fs_info; 1208 } 1209 static inline struct ext4_inode_info *EXT4_I(struct inode *inode) 1210 { 1211 return container_of(inode, struct ext4_inode_info, vfs_inode); 1212 } 1213 1214 static inline struct timespec ext4_current_time(struct inode *inode) 1215 { 1216 return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ? 1217 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC; 1218 } 1219 1220 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino) 1221 { 1222 return ino == EXT4_ROOT_INO || 1223 ino == EXT4_JOURNAL_INO || 1224 ino == EXT4_RESIZE_INO || 1225 (ino >= EXT4_FIRST_INO(sb) && 1226 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)); 1227 } 1228 1229 /* 1230 * Inode dynamic state flags 1231 */ 1232 enum { 1233 EXT4_STATE_JDATA, /* journaled data exists */ 1234 EXT4_STATE_NEW, /* inode is newly created */ 1235 EXT4_STATE_XATTR, /* has in-inode xattrs */ 1236 EXT4_STATE_NO_EXPAND, /* No space for expansion */ 1237 EXT4_STATE_DA_ALLOC_CLOSE, /* Alloc DA blks on close */ 1238 EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */ 1239 EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/ 1240 EXT4_STATE_NEWENTRY, /* File just added to dir */ 1241 EXT4_STATE_DELALLOC_RESERVED, /* blks already reserved for delalloc */ 1242 }; 1243 1244 #define EXT4_INODE_BIT_FNS(name, field, offset) \ 1245 static inline int ext4_test_inode_##name(struct inode *inode, int bit) \ 1246 { \ 1247 return test_bit(bit + (offset), &EXT4_I(inode)->i_##field); \ 1248 } \ 1249 static inline void ext4_set_inode_##name(struct inode *inode, int bit) \ 1250 { \ 1251 set_bit(bit + (offset), &EXT4_I(inode)->i_##field); \ 1252 } \ 1253 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \ 1254 { \ 1255 clear_bit(bit + (offset), &EXT4_I(inode)->i_##field); \ 1256 } 1257 1258 EXT4_INODE_BIT_FNS(flag, flags, 0) 1259 #if (BITS_PER_LONG < 64) 1260 EXT4_INODE_BIT_FNS(state, state_flags, 0) 1261 1262 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei) 1263 { 1264 (ei)->i_state_flags = 0; 1265 } 1266 #else 1267 EXT4_INODE_BIT_FNS(state, flags, 32) 1268 1269 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei) 1270 { 1271 /* We depend on the fact that callers will set i_flags */ 1272 } 1273 #endif 1274 #else 1275 /* Assume that user mode programs are passing in an ext4fs superblock, not 1276 * a kernel struct super_block. This will allow us to call the feature-test 1277 * macros from user land. */ 1278 #define EXT4_SB(sb) (sb) 1279 #endif 1280 1281 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime 1282 1283 /* 1284 * Codes for operating systems 1285 */ 1286 #define EXT4_OS_LINUX 0 1287 #define EXT4_OS_HURD 1 1288 #define EXT4_OS_MASIX 2 1289 #define EXT4_OS_FREEBSD 3 1290 #define EXT4_OS_LITES 4 1291 1292 /* 1293 * Revision levels 1294 */ 1295 #define EXT4_GOOD_OLD_REV 0 /* The good old (original) format */ 1296 #define EXT4_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 1297 1298 #define EXT4_CURRENT_REV EXT4_GOOD_OLD_REV 1299 #define EXT4_MAX_SUPP_REV EXT4_DYNAMIC_REV 1300 1301 #define EXT4_GOOD_OLD_INODE_SIZE 128 1302 1303 /* 1304 * Feature set definitions 1305 */ 1306 1307 #define EXT4_HAS_COMPAT_FEATURE(sb,mask) \ 1308 ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0) 1309 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask) \ 1310 ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0) 1311 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask) \ 1312 ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0) 1313 #define EXT4_SET_COMPAT_FEATURE(sb,mask) \ 1314 EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask) 1315 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask) \ 1316 EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask) 1317 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask) \ 1318 EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask) 1319 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask) \ 1320 EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask) 1321 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask) \ 1322 EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask) 1323 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask) \ 1324 EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask) 1325 1326 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001 1327 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002 1328 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004 1329 #define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008 1330 #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010 1331 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020 1332 1333 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 1334 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 1335 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 1336 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 1337 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 1338 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 1339 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 1340 1341 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001 1342 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002 1343 #define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 1344 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 1345 #define EXT4_FEATURE_INCOMPAT_META_BG 0x0010 1346 #define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */ 1347 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 1348 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100 1349 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 1350 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */ 1351 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */ 1352 1353 #define EXT4_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR 1354 #define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \ 1355 EXT4_FEATURE_INCOMPAT_RECOVER| \ 1356 EXT4_FEATURE_INCOMPAT_META_BG| \ 1357 EXT4_FEATURE_INCOMPAT_EXTENTS| \ 1358 EXT4_FEATURE_INCOMPAT_64BIT| \ 1359 EXT4_FEATURE_INCOMPAT_FLEX_BG) 1360 #define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 1361 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \ 1362 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \ 1363 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \ 1364 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \ 1365 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\ 1366 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) 1367 1368 /* 1369 * Default values for user and/or group using reserved blocks 1370 */ 1371 #define EXT4_DEF_RESUID 0 1372 #define EXT4_DEF_RESGID 0 1373 1374 #define EXT4_DEF_INODE_READAHEAD_BLKS 32 1375 1376 /* 1377 * Default mount options 1378 */ 1379 #define EXT4_DEFM_DEBUG 0x0001 1380 #define EXT4_DEFM_BSDGROUPS 0x0002 1381 #define EXT4_DEFM_XATTR_USER 0x0004 1382 #define EXT4_DEFM_ACL 0x0008 1383 #define EXT4_DEFM_UID16 0x0010 1384 #define EXT4_DEFM_JMODE 0x0060 1385 #define EXT4_DEFM_JMODE_DATA 0x0020 1386 #define EXT4_DEFM_JMODE_ORDERED 0x0040 1387 #define EXT4_DEFM_JMODE_WBACK 0x0060 1388 #define EXT4_DEFM_NOBARRIER 0x0100 1389 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200 1390 #define EXT4_DEFM_DISCARD 0x0400 1391 #define EXT4_DEFM_NODELALLOC 0x0800 1392 1393 /* 1394 * Default journal batch times 1395 */ 1396 #define EXT4_DEF_MIN_BATCH_TIME 0 1397 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */ 1398 1399 /* 1400 * Minimum number of groups in a flexgroup before we separate out 1401 * directories into the first block group of a flexgroup 1402 */ 1403 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4 1404 1405 /* 1406 * Structure of a directory entry 1407 */ 1408 #define EXT4_NAME_LEN 255 1409 1410 struct ext4_dir_entry { 1411 __le32 inode; /* Inode number */ 1412 __le16 rec_len; /* Directory entry length */ 1413 __le16 name_len; /* Name length */ 1414 char name[EXT4_NAME_LEN]; /* File name */ 1415 }; 1416 1417 /* 1418 * The new version of the directory entry. Since EXT4 structures are 1419 * stored in intel byte order, and the name_len field could never be 1420 * bigger than 255 chars, it's safe to reclaim the extra byte for the 1421 * file_type field. 1422 */ 1423 struct ext4_dir_entry_2 { 1424 __le32 inode; /* Inode number */ 1425 __le16 rec_len; /* Directory entry length */ 1426 __u8 name_len; /* Name length */ 1427 __u8 file_type; 1428 char name[EXT4_NAME_LEN]; /* File name */ 1429 }; 1430 1431 /* 1432 * Ext4 directory file types. Only the low 3 bits are used. The 1433 * other bits are reserved for now. 1434 */ 1435 #define EXT4_FT_UNKNOWN 0 1436 #define EXT4_FT_REG_FILE 1 1437 #define EXT4_FT_DIR 2 1438 #define EXT4_FT_CHRDEV 3 1439 #define EXT4_FT_BLKDEV 4 1440 #define EXT4_FT_FIFO 5 1441 #define EXT4_FT_SOCK 6 1442 #define EXT4_FT_SYMLINK 7 1443 1444 #define EXT4_FT_MAX 8 1445 1446 /* 1447 * EXT4_DIR_PAD defines the directory entries boundaries 1448 * 1449 * NOTE: It must be a multiple of 4 1450 */ 1451 #define EXT4_DIR_PAD 4 1452 #define EXT4_DIR_ROUND (EXT4_DIR_PAD - 1) 1453 #define EXT4_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT4_DIR_ROUND) & \ 1454 ~EXT4_DIR_ROUND) 1455 #define EXT4_MAX_REC_LEN ((1<<16)-1) 1456 1457 /* 1458 * If we ever get support for fs block sizes > page_size, we'll need 1459 * to remove the #if statements in the next two functions... 1460 */ 1461 static inline unsigned int 1462 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize) 1463 { 1464 unsigned len = le16_to_cpu(dlen); 1465 1466 #if (PAGE_CACHE_SIZE >= 65536) 1467 if (len == EXT4_MAX_REC_LEN || len == 0) 1468 return blocksize; 1469 return (len & 65532) | ((len & 3) << 16); 1470 #else 1471 return len; 1472 #endif 1473 } 1474 1475 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize) 1476 { 1477 if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3)) 1478 BUG(); 1479 #if (PAGE_CACHE_SIZE >= 65536) 1480 if (len < 65536) 1481 return cpu_to_le16(len); 1482 if (len == blocksize) { 1483 if (blocksize == 65536) 1484 return cpu_to_le16(EXT4_MAX_REC_LEN); 1485 else 1486 return cpu_to_le16(0); 1487 } 1488 return cpu_to_le16((len & 65532) | ((len >> 16) & 3)); 1489 #else 1490 return cpu_to_le16(len); 1491 #endif 1492 } 1493 1494 /* 1495 * Hash Tree Directory indexing 1496 * (c) Daniel Phillips, 2001 1497 */ 1498 1499 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \ 1500 EXT4_FEATURE_COMPAT_DIR_INDEX) && \ 1501 ext4_test_inode_flag((dir), EXT4_INODE_INDEX)) 1502 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX) 1503 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1) 1504 1505 /* Legal values for the dx_root hash_version field: */ 1506 1507 #define DX_HASH_LEGACY 0 1508 #define DX_HASH_HALF_MD4 1 1509 #define DX_HASH_TEA 2 1510 #define DX_HASH_LEGACY_UNSIGNED 3 1511 #define DX_HASH_HALF_MD4_UNSIGNED 4 1512 #define DX_HASH_TEA_UNSIGNED 5 1513 1514 #ifdef __KERNEL__ 1515 1516 /* hash info structure used by the directory hash */ 1517 struct dx_hash_info 1518 { 1519 u32 hash; 1520 u32 minor_hash; 1521 int hash_version; 1522 u32 *seed; 1523 }; 1524 1525 #define EXT4_HTREE_EOF 0x7fffffff 1526 1527 /* 1528 * Control parameters used by ext4_htree_next_block 1529 */ 1530 #define HASH_NB_ALWAYS 1 1531 1532 1533 /* 1534 * Describe an inode's exact location on disk and in memory 1535 */ 1536 struct ext4_iloc 1537 { 1538 struct buffer_head *bh; 1539 unsigned long offset; 1540 ext4_group_t block_group; 1541 }; 1542 1543 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc) 1544 { 1545 return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset); 1546 } 1547 1548 /* 1549 * This structure is stuffed into the struct file's private_data field 1550 * for directories. It is where we put information so that we can do 1551 * readdir operations in hash tree order. 1552 */ 1553 struct dir_private_info { 1554 struct rb_root root; 1555 struct rb_node *curr_node; 1556 struct fname *extra_fname; 1557 loff_t last_pos; 1558 __u32 curr_hash; 1559 __u32 curr_minor_hash; 1560 __u32 next_hash; 1561 }; 1562 1563 /* calculate the first block number of the group */ 1564 static inline ext4_fsblk_t 1565 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no) 1566 { 1567 return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) + 1568 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block); 1569 } 1570 1571 /* 1572 * Special error return code only used by dx_probe() and its callers. 1573 */ 1574 #define ERR_BAD_DX_DIR -75000 1575 1576 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr, 1577 ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp); 1578 1579 /* 1580 * Timeout and state flag for lazy initialization inode thread. 1581 */ 1582 #define EXT4_DEF_LI_WAIT_MULT 10 1583 #define EXT4_DEF_LI_MAX_START_DELAY 5 1584 #define EXT4_LAZYINIT_QUIT 0x0001 1585 #define EXT4_LAZYINIT_RUNNING 0x0002 1586 1587 /* 1588 * Lazy inode table initialization info 1589 */ 1590 struct ext4_lazy_init { 1591 unsigned long li_state; 1592 1593 wait_queue_head_t li_wait_daemon; 1594 wait_queue_head_t li_wait_task; 1595 struct timer_list li_timer; 1596 struct task_struct *li_task; 1597 1598 struct list_head li_request_list; 1599 struct mutex li_list_mtx; 1600 }; 1601 1602 struct ext4_li_request { 1603 struct super_block *lr_super; 1604 struct ext4_sb_info *lr_sbi; 1605 ext4_group_t lr_next_group; 1606 struct list_head lr_request; 1607 unsigned long lr_next_sched; 1608 unsigned long lr_timeout; 1609 }; 1610 1611 struct ext4_features { 1612 struct kobject f_kobj; 1613 struct completion f_kobj_unregister; 1614 }; 1615 1616 /* 1617 * Function prototypes 1618 */ 1619 1620 /* 1621 * Ok, these declarations are also in <linux/kernel.h> but none of the 1622 * ext4 source programs needs to include it so they are duplicated here. 1623 */ 1624 # define NORET_TYPE /**/ 1625 # define ATTRIB_NORET __attribute__((noreturn)) 1626 # define NORET_AND noreturn, 1627 1628 /* bitmap.c */ 1629 extern unsigned int ext4_count_free(struct buffer_head *, unsigned); 1630 1631 /* balloc.c */ 1632 extern unsigned int ext4_block_group(struct super_block *sb, 1633 ext4_fsblk_t blocknr); 1634 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb, 1635 ext4_fsblk_t blocknr); 1636 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group); 1637 extern unsigned long ext4_bg_num_gdb(struct super_block *sb, 1638 ext4_group_t group); 1639 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode, 1640 ext4_fsblk_t goal, unsigned long *count, int *errp); 1641 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks); 1642 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb, 1643 ext4_fsblk_t block, unsigned long count); 1644 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *); 1645 extern void ext4_check_blocks_bitmap(struct super_block *); 1646 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb, 1647 ext4_group_t block_group, 1648 struct buffer_head ** bh); 1649 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries); 1650 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb, 1651 ext4_group_t block_group); 1652 extern unsigned ext4_init_block_bitmap(struct super_block *sb, 1653 struct buffer_head *bh, 1654 ext4_group_t group, 1655 struct ext4_group_desc *desc); 1656 #define ext4_free_blocks_after_init(sb, group, desc) \ 1657 ext4_init_block_bitmap(sb, NULL, group, desc) 1658 1659 /* dir.c */ 1660 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *, 1661 struct file *, 1662 struct ext4_dir_entry_2 *, 1663 struct buffer_head *, unsigned int); 1664 #define ext4_check_dir_entry(dir, filp, de, bh, offset) \ 1665 unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \ 1666 (de), (bh), (offset))) 1667 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash, 1668 __u32 minor_hash, 1669 struct ext4_dir_entry_2 *dirent); 1670 extern void ext4_htree_free_dir_info(struct dir_private_info *p); 1671 1672 /* fsync.c */ 1673 extern int ext4_sync_file(struct file *, int); 1674 extern int ext4_flush_completed_IO(struct inode *); 1675 1676 /* hash.c */ 1677 extern int ext4fs_dirhash(const char *name, int len, struct 1678 dx_hash_info *hinfo); 1679 1680 /* ialloc.c */ 1681 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int, 1682 const struct qstr *qstr, __u32 goal); 1683 extern void ext4_free_inode(handle_t *, struct inode *); 1684 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long); 1685 extern unsigned long ext4_count_free_inodes(struct super_block *); 1686 extern unsigned long ext4_count_dirs(struct super_block *); 1687 extern void ext4_check_inodes_bitmap(struct super_block *); 1688 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap); 1689 extern int ext4_init_inode_table(struct super_block *sb, 1690 ext4_group_t group, int barrier); 1691 1692 /* mballoc.c */ 1693 extern long ext4_mb_stats; 1694 extern long ext4_mb_max_to_scan; 1695 extern int ext4_mb_init(struct super_block *, int); 1696 extern int ext4_mb_release(struct super_block *); 1697 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *, 1698 struct ext4_allocation_request *, int *); 1699 extern int ext4_mb_reserve_blocks(struct super_block *, int); 1700 extern void ext4_discard_preallocations(struct inode *); 1701 extern int __init ext4_init_mballoc(void); 1702 extern void ext4_exit_mballoc(void); 1703 extern void ext4_free_blocks(handle_t *handle, struct inode *inode, 1704 struct buffer_head *bh, ext4_fsblk_t block, 1705 unsigned long count, int flags); 1706 extern int ext4_mb_add_groupinfo(struct super_block *sb, 1707 ext4_group_t i, struct ext4_group_desc *desc); 1708 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *); 1709 1710 /* inode.c */ 1711 struct buffer_head *ext4_getblk(handle_t *, struct inode *, 1712 ext4_lblk_t, int, int *); 1713 struct buffer_head *ext4_bread(handle_t *, struct inode *, 1714 ext4_lblk_t, int, int *); 1715 int ext4_get_block(struct inode *inode, sector_t iblock, 1716 struct buffer_head *bh_result, int create); 1717 1718 extern struct inode *ext4_iget(struct super_block *, unsigned long); 1719 extern int ext4_write_inode(struct inode *, struct writeback_control *); 1720 extern int ext4_setattr(struct dentry *, struct iattr *); 1721 extern int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, 1722 struct kstat *stat); 1723 extern void ext4_evict_inode(struct inode *); 1724 extern void ext4_clear_inode(struct inode *); 1725 extern int ext4_sync_inode(handle_t *, struct inode *); 1726 extern void ext4_dirty_inode(struct inode *); 1727 extern int ext4_change_inode_journal_flag(struct inode *, int); 1728 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *); 1729 extern int ext4_can_truncate(struct inode *inode); 1730 extern void ext4_truncate(struct inode *); 1731 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks); 1732 extern void ext4_set_inode_flags(struct inode *); 1733 extern void ext4_get_inode_flags(struct ext4_inode_info *); 1734 extern int ext4_alloc_da_blocks(struct inode *inode); 1735 extern void ext4_set_aops(struct inode *inode); 1736 extern int ext4_writepage_trans_blocks(struct inode *); 1737 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks); 1738 extern int ext4_block_truncate_page(handle_t *handle, 1739 struct address_space *mapping, loff_t from); 1740 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf); 1741 extern qsize_t *ext4_get_reserved_space(struct inode *inode); 1742 extern void ext4_da_update_reserve_space(struct inode *inode, 1743 int used, int quota_claim); 1744 /* ioctl.c */ 1745 extern long ext4_ioctl(struct file *, unsigned int, unsigned long); 1746 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long); 1747 1748 /* migrate.c */ 1749 extern int ext4_ext_migrate(struct inode *); 1750 1751 /* namei.c */ 1752 extern int ext4_orphan_add(handle_t *, struct inode *); 1753 extern int ext4_orphan_del(handle_t *, struct inode *); 1754 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, 1755 __u32 start_minor_hash, __u32 *next_hash); 1756 1757 /* resize.c */ 1758 extern int ext4_group_add(struct super_block *sb, 1759 struct ext4_new_group_data *input); 1760 extern int ext4_group_extend(struct super_block *sb, 1761 struct ext4_super_block *es, 1762 ext4_fsblk_t n_blocks_count); 1763 1764 /* super.c */ 1765 extern void __ext4_error(struct super_block *, const char *, unsigned int, 1766 const char *, ...) 1767 __attribute__ ((format (printf, 4, 5))); 1768 #define ext4_error(sb, message...) __ext4_error(sb, __func__, \ 1769 __LINE__, ## message) 1770 extern void ext4_error_inode(struct inode *, const char *, unsigned int, 1771 ext4_fsblk_t, const char *, ...) 1772 __attribute__ ((format (printf, 5, 6))); 1773 extern void ext4_error_file(struct file *, const char *, unsigned int, 1774 ext4_fsblk_t, const char *, ...) 1775 __attribute__ ((format (printf, 5, 6))); 1776 extern void __ext4_std_error(struct super_block *, const char *, 1777 unsigned int, int); 1778 extern void __ext4_abort(struct super_block *, const char *, unsigned int, 1779 const char *, ...) 1780 __attribute__ ((format (printf, 4, 5))); 1781 #define ext4_abort(sb, message...) __ext4_abort(sb, __func__, \ 1782 __LINE__, ## message) 1783 extern void __ext4_warning(struct super_block *, const char *, unsigned int, 1784 const char *, ...) 1785 __attribute__ ((format (printf, 4, 5))); 1786 #define ext4_warning(sb, message...) __ext4_warning(sb, __func__, \ 1787 __LINE__, ## message) 1788 extern void ext4_msg(struct super_block *, const char *, const char *, ...) 1789 __attribute__ ((format (printf, 3, 4))); 1790 extern void __ext4_grp_locked_error(const char *, unsigned int, \ 1791 struct super_block *, ext4_group_t, \ 1792 unsigned long, ext4_fsblk_t, \ 1793 const char *, ...) 1794 __attribute__ ((format (printf, 7, 8))); 1795 #define ext4_grp_locked_error(sb, grp, message...) \ 1796 __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message) 1797 extern void ext4_update_dynamic_rev(struct super_block *sb); 1798 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb, 1799 __u32 compat); 1800 extern int ext4_update_rocompat_feature(handle_t *handle, 1801 struct super_block *sb, __u32 rocompat); 1802 extern int ext4_update_incompat_feature(handle_t *handle, 1803 struct super_block *sb, __u32 incompat); 1804 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb, 1805 struct ext4_group_desc *bg); 1806 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb, 1807 struct ext4_group_desc *bg); 1808 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb, 1809 struct ext4_group_desc *bg); 1810 extern __u32 ext4_free_blks_count(struct super_block *sb, 1811 struct ext4_group_desc *bg); 1812 extern __u32 ext4_free_inodes_count(struct super_block *sb, 1813 struct ext4_group_desc *bg); 1814 extern __u32 ext4_used_dirs_count(struct super_block *sb, 1815 struct ext4_group_desc *bg); 1816 extern __u32 ext4_itable_unused_count(struct super_block *sb, 1817 struct ext4_group_desc *bg); 1818 extern void ext4_block_bitmap_set(struct super_block *sb, 1819 struct ext4_group_desc *bg, ext4_fsblk_t blk); 1820 extern void ext4_inode_bitmap_set(struct super_block *sb, 1821 struct ext4_group_desc *bg, ext4_fsblk_t blk); 1822 extern void ext4_inode_table_set(struct super_block *sb, 1823 struct ext4_group_desc *bg, ext4_fsblk_t blk); 1824 extern void ext4_free_blks_set(struct super_block *sb, 1825 struct ext4_group_desc *bg, __u32 count); 1826 extern void ext4_free_inodes_set(struct super_block *sb, 1827 struct ext4_group_desc *bg, __u32 count); 1828 extern void ext4_used_dirs_set(struct super_block *sb, 1829 struct ext4_group_desc *bg, __u32 count); 1830 extern void ext4_itable_unused_set(struct super_block *sb, 1831 struct ext4_group_desc *bg, __u32 count); 1832 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group, 1833 struct ext4_group_desc *gdp); 1834 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group, 1835 struct ext4_group_desc *gdp); 1836 1837 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es) 1838 { 1839 return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) | 1840 le32_to_cpu(es->s_blocks_count_lo); 1841 } 1842 1843 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es) 1844 { 1845 return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) | 1846 le32_to_cpu(es->s_r_blocks_count_lo); 1847 } 1848 1849 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es) 1850 { 1851 return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) | 1852 le32_to_cpu(es->s_free_blocks_count_lo); 1853 } 1854 1855 static inline void ext4_blocks_count_set(struct ext4_super_block *es, 1856 ext4_fsblk_t blk) 1857 { 1858 es->s_blocks_count_lo = cpu_to_le32((u32)blk); 1859 es->s_blocks_count_hi = cpu_to_le32(blk >> 32); 1860 } 1861 1862 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es, 1863 ext4_fsblk_t blk) 1864 { 1865 es->s_free_blocks_count_lo = cpu_to_le32((u32)blk); 1866 es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32); 1867 } 1868 1869 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es, 1870 ext4_fsblk_t blk) 1871 { 1872 es->s_r_blocks_count_lo = cpu_to_le32((u32)blk); 1873 es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32); 1874 } 1875 1876 static inline loff_t ext4_isize(struct ext4_inode *raw_inode) 1877 { 1878 if (S_ISREG(le16_to_cpu(raw_inode->i_mode))) 1879 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) | 1880 le32_to_cpu(raw_inode->i_size_lo); 1881 else 1882 return (loff_t) le32_to_cpu(raw_inode->i_size_lo); 1883 } 1884 1885 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size) 1886 { 1887 raw_inode->i_size_lo = cpu_to_le32(i_size); 1888 raw_inode->i_size_high = cpu_to_le32(i_size >> 32); 1889 } 1890 1891 static inline 1892 struct ext4_group_info *ext4_get_group_info(struct super_block *sb, 1893 ext4_group_t group) 1894 { 1895 struct ext4_group_info ***grp_info; 1896 long indexv, indexh; 1897 grp_info = EXT4_SB(sb)->s_group_info; 1898 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb)); 1899 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1); 1900 return grp_info[indexv][indexh]; 1901 } 1902 1903 /* 1904 * Reading s_groups_count requires using smp_rmb() afterwards. See 1905 * the locking protocol documented in the comments of ext4_group_add() 1906 * in resize.c 1907 */ 1908 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb) 1909 { 1910 ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count; 1911 1912 smp_rmb(); 1913 return ngroups; 1914 } 1915 1916 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi, 1917 ext4_group_t block_group) 1918 { 1919 return block_group >> sbi->s_log_groups_per_flex; 1920 } 1921 1922 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi) 1923 { 1924 return 1 << sbi->s_log_groups_per_flex; 1925 } 1926 1927 #define ext4_std_error(sb, errno) \ 1928 do { \ 1929 if ((errno)) \ 1930 __ext4_std_error((sb), __func__, __LINE__, (errno)); \ 1931 } while (0) 1932 1933 #ifdef CONFIG_SMP 1934 /* Each CPU can accumulate percpu_counter_batch blocks in their local 1935 * counters. So we need to make sure we have free blocks more 1936 * than percpu_counter_batch * nr_cpu_ids. Also add a window of 4 times. 1937 */ 1938 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids)) 1939 #else 1940 #define EXT4_FREEBLOCKS_WATERMARK 0 1941 #endif 1942 1943 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize) 1944 { 1945 /* 1946 * XXX: replace with spinlock if seen contended -bzzz 1947 */ 1948 down_write(&EXT4_I(inode)->i_data_sem); 1949 if (newsize > EXT4_I(inode)->i_disksize) 1950 EXT4_I(inode)->i_disksize = newsize; 1951 up_write(&EXT4_I(inode)->i_data_sem); 1952 return ; 1953 } 1954 1955 struct ext4_group_info { 1956 unsigned long bb_state; 1957 struct rb_root bb_free_root; 1958 ext4_grpblk_t bb_first_free; /* first free block */ 1959 ext4_grpblk_t bb_free; /* total free blocks */ 1960 ext4_grpblk_t bb_fragments; /* nr of freespace fragments */ 1961 ext4_grpblk_t bb_largest_free_order;/* order of largest frag in BG */ 1962 struct list_head bb_prealloc_list; 1963 #ifdef DOUBLE_CHECK 1964 void *bb_bitmap; 1965 #endif 1966 struct rw_semaphore alloc_sem; 1967 ext4_grpblk_t bb_counters[]; /* Nr of free power-of-two-block 1968 * regions, index is order. 1969 * bb_counters[3] = 5 means 1970 * 5 free 8-block regions. */ 1971 }; 1972 1973 #define EXT4_GROUP_INFO_NEED_INIT_BIT 0 1974 1975 #define EXT4_MB_GRP_NEED_INIT(grp) \ 1976 (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state))) 1977 1978 #define EXT4_MAX_CONTENTION 8 1979 #define EXT4_CONTENTION_THRESHOLD 2 1980 1981 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb, 1982 ext4_group_t group) 1983 { 1984 return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group); 1985 } 1986 1987 /* 1988 * Returns true if the filesystem is busy enough that attempts to 1989 * access the block group locks has run into contention. 1990 */ 1991 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi) 1992 { 1993 return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD); 1994 } 1995 1996 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group) 1997 { 1998 spinlock_t *lock = ext4_group_lock_ptr(sb, group); 1999 if (spin_trylock(lock)) 2000 /* 2001 * We're able to grab the lock right away, so drop the 2002 * lock contention counter. 2003 */ 2004 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0); 2005 else { 2006 /* 2007 * The lock is busy, so bump the contention counter, 2008 * and then wait on the spin lock. 2009 */ 2010 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1, 2011 EXT4_MAX_CONTENTION); 2012 spin_lock(lock); 2013 } 2014 } 2015 2016 static inline void ext4_unlock_group(struct super_block *sb, 2017 ext4_group_t group) 2018 { 2019 spin_unlock(ext4_group_lock_ptr(sb, group)); 2020 } 2021 2022 static inline void ext4_mark_super_dirty(struct super_block *sb) 2023 { 2024 if (EXT4_SB(sb)->s_journal == NULL) 2025 sb->s_dirt =1; 2026 } 2027 2028 /* 2029 * Inodes and files operations 2030 */ 2031 2032 /* dir.c */ 2033 extern const struct file_operations ext4_dir_operations; 2034 2035 /* file.c */ 2036 extern const struct inode_operations ext4_file_inode_operations; 2037 extern const struct file_operations ext4_file_operations; 2038 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin); 2039 2040 /* namei.c */ 2041 extern const struct inode_operations ext4_dir_inode_operations; 2042 extern const struct inode_operations ext4_special_inode_operations; 2043 extern struct dentry *ext4_get_parent(struct dentry *child); 2044 2045 /* symlink.c */ 2046 extern const struct inode_operations ext4_symlink_inode_operations; 2047 extern const struct inode_operations ext4_fast_symlink_inode_operations; 2048 2049 /* block_validity */ 2050 extern void ext4_release_system_zone(struct super_block *sb); 2051 extern int ext4_setup_system_zone(struct super_block *sb); 2052 extern int __init ext4_init_system_zone(void); 2053 extern void ext4_exit_system_zone(void); 2054 extern int ext4_data_block_valid(struct ext4_sb_info *sbi, 2055 ext4_fsblk_t start_blk, 2056 unsigned int count); 2057 2058 /* extents.c */ 2059 extern int ext4_ext_tree_init(handle_t *handle, struct inode *); 2060 extern int ext4_ext_writepage_trans_blocks(struct inode *, int); 2061 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, 2062 int chunk); 2063 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, 2064 struct ext4_map_blocks *map, int flags); 2065 extern void ext4_ext_truncate(struct inode *); 2066 extern void ext4_ext_init(struct super_block *); 2067 extern void ext4_ext_release(struct super_block *); 2068 extern long ext4_fallocate(struct file *file, int mode, loff_t offset, 2069 loff_t len); 2070 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset, 2071 ssize_t len); 2072 extern int ext4_map_blocks(handle_t *handle, struct inode *inode, 2073 struct ext4_map_blocks *map, int flags); 2074 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 2075 __u64 start, __u64 len); 2076 /* move_extent.c */ 2077 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp, 2078 __u64 start_orig, __u64 start_donor, 2079 __u64 len, __u64 *moved_len); 2080 2081 /* page-io.c */ 2082 extern int __init ext4_init_pageio(void); 2083 extern void ext4_exit_pageio(void); 2084 extern void ext4_ioend_wait(struct inode *); 2085 extern void ext4_free_io_end(ext4_io_end_t *io); 2086 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags); 2087 extern int ext4_end_io_nolock(ext4_io_end_t *io); 2088 extern void ext4_io_submit(struct ext4_io_submit *io); 2089 extern int ext4_bio_write_page(struct ext4_io_submit *io, 2090 struct page *page, 2091 int len, 2092 struct writeback_control *wbc); 2093 2094 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */ 2095 enum ext4_state_bits { 2096 BH_Uninit /* blocks are allocated but uninitialized on disk */ 2097 = BH_JBDPrivateStart, 2098 }; 2099 2100 BUFFER_FNS(Uninit, uninit) 2101 TAS_BUFFER_FNS(Uninit, uninit) 2102 2103 /* 2104 * Add new method to test wether block and inode bitmaps are properly 2105 * initialized. With uninit_bg reading the block from disk is not enough 2106 * to mark the bitmap uptodate. We need to also zero-out the bitmap 2107 */ 2108 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart 2109 2110 static inline int bitmap_uptodate(struct buffer_head *bh) 2111 { 2112 return (buffer_uptodate(bh) && 2113 test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state)); 2114 } 2115 static inline void set_bitmap_uptodate(struct buffer_head *bh) 2116 { 2117 set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state); 2118 } 2119 2120 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1) 2121 2122 #endif /* __KERNEL__ */ 2123 2124 #endif /* _EXT4_H */ 2125