fs/ext4/ext4.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  ext4.h
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/include/linux/minix_fs.h
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  */
  16
  17 #ifndef _EXT4_H
  18 #define _EXT4_H
  19
  20 #include <linux/types.h>
  21 #include <linux/blkdev.h>
  22 #include <linux/magic.h>
  23 #include <linux/jbd2.h>
  24 #include <linux/quota.h>
  25 #include <linux/rwsem.h>
  26 #include <linux/rbtree.h>
  27 #include <linux/seqlock.h>
  28 #include <linux/mutex.h>
  29 #include <linux/timer.h>
  30 #include <linux/wait.h>
  31 #include <linux/sched/signal.h>
  32 #include <linux/blockgroup_lock.h>
  33 #include <linux/percpu_counter.h>
  34 #include <linux/ratelimit.h>
  35 #include <crypto/hash.h>
  36 #include <linux/falloc.h>
  37 #include <linux/percpu-rwsem.h>
  38 #include <linux/fiemap.h>
  39 #ifdef __KERNEL__
  40 #include <linux/compat.h>
  41 #endif
  42
  43 #include <linux/fscrypt.h>
  44 #include <linux/fsverity.h>
  45
  46 #include <linux/compiler.h>
  47
  48 /*
  49  * The fourth extended filesystem constants/structures
  50  */
  51
  52 /*
  53  * with AGGRESSIVE_CHECK allocator runs consistency checks over
  54  * structures. these checks slow things down a lot
  55  */
  56 #define AGGRESSIVE_CHECK__
  57
  58 /*
  59  * with DOUBLE_CHECK defined mballoc creates persistent in-core
  60  * bitmaps, maintains and uses them to check for double allocations
  61  */
  62 #define DOUBLE_CHECK__
  63
  64 /*
  65  * Define EXT4FS_DEBUG to produce debug messages
  66  */
  67 #undef EXT4FS_DEBUG
  68
  69 /*
  70  * Debug code
  71  */
  72 #ifdef EXT4FS_DEBUG
  73 #define ext4_debug(f, a...)                                             \
  74         do {                                                            \
  75                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  76                         __FILE__, __LINE__, __func__);                  \
  77                 printk(KERN_DEBUG f, ## a);                             \
  78         } while (0)
  79 #else
  80 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
  81 #endif
  82
  83  /*
  84   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
  85   */
  86 #define EXT_DEBUG__
  87
  88 /*
  89  * Dynamic printk for controlled extents debugging.
  90  */
  91 #ifdef CONFIG_EXT4_DEBUG
  92 #define ext_debug(ino, fmt, ...)                                        \
  93         pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,    \
  94                  current->comm, task_pid_nr(current),                   \
  95                  ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,       \
  96                  __func__, ##__VA_ARGS__)
  97 #else
  98 #define ext_debug(ino, fmt, ...)        no_printk(fmt, ##__VA_ARGS__)
  99 #endif
 100
 101 #define ASSERT(assert)                                          \
 102 do {                                                                    \
 103         if (unlikely(!(assert))) {                                      \
 104                 printk(KERN_EMERG                                       \
 105                        "Assertion failure in %s() at %s:%d: '%s'\n",    \
 106                        __func__, __FILE__, __LINE__, #assert);          \
 107                 BUG();                                                  \
 108         }                                                               \
 109 } while (0)
 110
 111 /* data type for block offset of block group */
 112 typedef int ext4_grpblk_t;
 113
 114 /* data type for filesystem-wide blocks number */
 115 typedef unsigned long long ext4_fsblk_t;
 116
 117 /* data type for file logical block number */
 118 typedef __u32 ext4_lblk_t;
 119
 120 /* data type for block group number */
 121 typedef unsigned int ext4_group_t;
 122
 123 enum SHIFT_DIRECTION {
 124         SHIFT_LEFT = 0,
 125         SHIFT_RIGHT,
 126 };
 127
 128 /*
 129  * Flags used in mballoc's allocation_context flags field.
 130  *
 131  * Also used to show what's going on for debugging purposes when the
 132  * flag field is exported via the traceport interface
 133  */
 134
 135 /* prefer goal again. length */
 136 #define EXT4_MB_HINT_MERGE              0x0001
 137 /* blocks already reserved */
 138 #define EXT4_MB_HINT_RESERVED           0x0002
 139 /* metadata is being allocated */
 140 #define EXT4_MB_HINT_METADATA           0x0004
 141 /* first blocks in the file */
 142 #define EXT4_MB_HINT_FIRST              0x0008
 143 /* search for the best chunk */
 144 #define EXT4_MB_HINT_BEST               0x0010
 145 /* data is being allocated */
 146 #define EXT4_MB_HINT_DATA               0x0020
 147 /* don't preallocate (for tails) */
 148 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 149 /* allocate for locality group */
 150 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 151 /* allocate goal blocks or none */
 152 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 153 /* goal is meaningful */
 154 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 155 /* blocks already pre-reserved by delayed allocation */
 156 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 157 /* We are doing stream allocation */
 158 #define EXT4_MB_STREAM_ALLOC            0x0800
 159 /* Use reserved root blocks if needed */
 160 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 161 /* Use blocks from reserved pool */
 162 #define EXT4_MB_USE_RESERVED            0x2000
 163 /* Do strict check for free blocks while retrying block allocation */
 164 #define EXT4_MB_STRICT_CHECK            0x4000
 165 /* Large fragment size list lookup succeeded at least once for cr = 0 */
 166 #define EXT4_MB_CR0_OPTIMIZED           0x8000
 167 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1 */
 168 #define EXT4_MB_CR1_OPTIMIZED           0x00010000
 169 /* Perform linear traversal for one group */
 170 #define EXT4_MB_SEARCH_NEXT_LINEAR      0x00020000
 171 struct ext4_allocation_request {
 172         /* target inode for block we're allocating */
 173         struct inode *inode;
 174         /* how many blocks we want to allocate */
 175         unsigned int len;
 176         /* logical block in target inode */
 177         ext4_lblk_t logical;
 178         /* the closest logical allocated block to the left */
 179         ext4_lblk_t lleft;
 180         /* the closest logical allocated block to the right */
 181         ext4_lblk_t lright;
 182         /* phys. target (a hint) */
 183         ext4_fsblk_t goal;
 184         /* phys. block for the closest logical allocated block to the left */
 185         ext4_fsblk_t pleft;
 186         /* phys. block for the closest logical allocated block to the right */
 187         ext4_fsblk_t pright;
 188         /* flags. see above EXT4_MB_HINT_* */
 189         unsigned int flags;
 190 };
 191
 192 /*
 193  * Logical to physical block mapping, used by ext4_map_blocks()
 194  *
 195  * This structure is used to pass requests into ext4_map_blocks() as
 196  * well as to store the information returned by ext4_map_blocks().  It
 197  * takes less room on the stack than a struct buffer_head.
 198  */
 199 #define EXT4_MAP_NEW            BIT(BH_New)
 200 #define EXT4_MAP_MAPPED         BIT(BH_Mapped)
 201 #define EXT4_MAP_UNWRITTEN      BIT(BH_Unwritten)
 202 #define EXT4_MAP_BOUNDARY       BIT(BH_Boundary)
 203 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 204                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
 205
 206 struct ext4_map_blocks {
 207         ext4_fsblk_t m_pblk;
 208         ext4_lblk_t m_lblk;
 209         unsigned int m_len;
 210         unsigned int m_flags;
 211 };
 212
 213 /*
 214  * Block validity checking, system zone rbtree.
 215  */
 216 struct ext4_system_blocks {
 217         struct rb_root root;
 218         struct rcu_head rcu;
 219 };
 220
 221 /*
 222  * Flags for ext4_io_end->flags
 223  */
 224 #define EXT4_IO_END_UNWRITTEN   0x0001
 225
 226 struct ext4_io_end_vec {
 227         struct list_head list;          /* list of io_end_vec */
 228         loff_t offset;                  /* offset in the file */
 229         ssize_t size;                   /* size of the extent */
 230 };
 231
 232 /*
 233  * For converting unwritten extents on a work queue. 'handle' is used for
 234  * buffered writeback.
 235  */
 236 typedef struct ext4_io_end {
 237         struct list_head        list;           /* per-file finished IO list */
 238         handle_t                *handle;        /* handle reserved for extent
 239                                                  * conversion */
 240         struct inode            *inode;         /* file being written to */
 241         struct bio              *bio;           /* Linked list of completed
 242                                                  * bios covering the extent */
 243         unsigned int            flag;           /* unwritten or not */
 244         atomic_t                count;          /* reference counter */
 245         struct list_head        list_vec;       /* list of ext4_io_end_vec */
 246 } ext4_io_end_t;
 247
 248 struct ext4_io_submit {
 249         struct writeback_control *io_wbc;
 250         struct bio              *io_bio;
 251         ext4_io_end_t           *io_end;
 252         sector_t                io_next_block;
 253 };
 254
 255 /*
 256  * Special inodes numbers
 257  */
 258 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 259 #define EXT4_ROOT_INO            2      /* Root inode */
 260 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 261 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 262 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 263 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 264 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 265 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 266
 267 /* First non-reserved inode for old ext4 filesystems */
 268 #define EXT4_GOOD_OLD_FIRST_INO 11
 269
 270 /*
 271  * Maximal count of links to a file
 272  */
 273 #define EXT4_LINK_MAX           65000
 274
 275 /*
 276  * Macro-instructions used to manage several block sizes
 277  */
 278 #define EXT4_MIN_BLOCK_SIZE             1024
 279 #define EXT4_MAX_BLOCK_SIZE             65536
 280 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 281 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 282 #define EXT4_MAX_CLUSTER_LOG_SIZE       30
 283 #ifdef __KERNEL__
 284 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 285 #else
 286 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 287 #endif
 288 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 289 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 290                                          EXT4_SB(s)->s_cluster_bits)
 291 #ifdef __KERNEL__
 292 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 293 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 294 #else
 295 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 296 #endif
 297 #ifdef __KERNEL__
 298 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 299 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 300 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 301 #else
 302 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 303                                  EXT4_GOOD_OLD_INODE_SIZE : \
 304                                  (s)->s_inode_size)
 305 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 306                                  EXT4_GOOD_OLD_FIRST_INO : \
 307                                  (s)->s_first_ino)
 308 #endif
 309 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 310 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
 311         ((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
 312                                                                   blkbits))
 313
 314 /* Translate a block number to a cluster number */
 315 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 316 /* Translate a cluster number to a block number */
 317 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 318 /* Translate # of blks to # of clusters */
 319 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 320                                  (sbi)->s_cluster_bits)
 321 /* Mask out the low bits to get the starting block of the cluster */
 322 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &                              \
 323                                   ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
 324 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &                              \
 325                                   ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
 326 /* Fill in the low bits to get the last block of the cluster */
 327 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |                            \
 328                                     ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
 329 /* Get the cluster offset */
 330 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &                               \
 331                                  ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
 332 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &                               \
 333                                  ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
 334
 335 /*
 336  * Structure of a blocks group descriptor
 337  */
 338 struct ext4_group_desc
 339 {
 340         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 341         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 342         __le32  bg_inode_table_lo;      /* Inodes table block */
 343         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 344         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 345         __le16  bg_used_dirs_count_lo;  /* Directories count */
 346         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 347         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 348         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 349         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 350         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 351         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 352         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 353         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 354         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 355         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 356         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 357         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 358         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 359         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 360         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 361         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 362         __u32   bg_reserved;
 363 };
 364
 365 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 366         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 367          sizeof(__le16))
 368 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 369         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 370          sizeof(__le16))
 371
 372 /*
 373  * Structure of a flex block group info
 374  */
 375
 376 struct flex_groups {
 377         atomic64_t      free_clusters;
 378         atomic_t        free_inodes;
 379         atomic_t        used_dirs;
 380 };
 381
 382 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 383 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 384 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 385
 386 /*
 387  * Macro-instructions used to manage group descriptors
 388  */
 389 #define EXT4_MIN_DESC_SIZE              32
 390 #define EXT4_MIN_DESC_SIZE_64BIT        64
 391 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 392 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 393 #ifdef __KERNEL__
 394 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 395 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 396 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 397 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 398 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 399 #else
 400 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 401 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 402 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 403 #endif
 404
 405 /*
 406  * Constants relative to the data blocks
 407  */
 408 #define EXT4_NDIR_BLOCKS                12
 409 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 410 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 411 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 412 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 413
 414 /*
 415  * Inode flags
 416  */
 417 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 418 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 419 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 420 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 421 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 422 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 423 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 424 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 425 /* Reserved for compression usage... */
 426 #define EXT4_DIRTY_FL                   0x00000100
 427 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 428 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 429         /* nb: was previously EXT2_ECOMPR_FL */
 430 #define EXT4_ENCRYPT_FL                 0x00000800 /* encrypted file */
 431 /* End compression flags --- maybe not all used */
 432 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 433 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 434 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 435 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 436 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 437 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 438 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 439 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 440 #define EXT4_VERITY_FL                  0x00100000 /* Verity protected inode */
 441 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 442 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
 443
 444 #define EXT4_DAX_FL                     0x02000000 /* Inode is DAX */
 445
 446 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
 447 #define EXT4_PROJINHERIT_FL             0x20000000 /* Create with parents projid */
 448 #define EXT4_CASEFOLD_FL                0x40000000 /* Casefolded directory */
 449 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 450
 451 /* User modifiable flags */
 452 #define EXT4_FL_USER_MODIFIABLE         (EXT4_SECRM_FL | \
 453                                          EXT4_UNRM_FL | \
 454                                          EXT4_COMPR_FL | \
 455                                          EXT4_SYNC_FL | \
 456                                          EXT4_IMMUTABLE_FL | \
 457                                          EXT4_APPEND_FL | \
 458                                          EXT4_NODUMP_FL | \
 459                                          EXT4_NOATIME_FL | \
 460                                          EXT4_JOURNAL_DATA_FL | \
 461                                          EXT4_NOTAIL_FL | \
 462                                          EXT4_DIRSYNC_FL | \
 463                                          EXT4_TOPDIR_FL | \
 464                                          EXT4_EXTENTS_FL | \
 465                                          0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
 466                                          EXT4_DAX_FL | \
 467                                          EXT4_PROJINHERIT_FL | \
 468                                          EXT4_CASEFOLD_FL)
 469
 470 /* User visible flags */
 471 #define EXT4_FL_USER_VISIBLE            (EXT4_FL_USER_MODIFIABLE | \
 472                                          EXT4_DIRTY_FL | \
 473                                          EXT4_COMPRBLK_FL | \
 474                                          EXT4_NOCOMPR_FL | \
 475                                          EXT4_ENCRYPT_FL | \
 476                                          EXT4_INDEX_FL | \
 477                                          EXT4_VERITY_FL | \
 478                                          EXT4_INLINE_DATA_FL)
 479
 480 /* Flags that should be inherited by new inodes from their parent. */
 481 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 482                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 483                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 484                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
 485                            EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
 486                            EXT4_DAX_FL)
 487
 488 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 489 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
 490                            EXT4_PROJINHERIT_FL))
 491
 492 /* Flags that are appropriate for non-directories/regular files. */
 493 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 494
 495 /* The only flags that should be swapped */
 496 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
 497
 498 /* Flags which are mutually exclusive to DAX */
 499 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
 500                            EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_FL)
 501
 502 /* Mask out flags that are inappropriate for the given type of inode. */
 503 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 504 {
 505         if (S_ISDIR(mode))
 506                 return flags;
 507         else if (S_ISREG(mode))
 508                 return flags & EXT4_REG_FLMASK;
 509         else
 510                 return flags & EXT4_OTHER_FLMASK;
 511 }
 512
 513 /*
 514  * Inode flags used for atomic set/get
 515  */
 516 enum {
 517         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 518         EXT4_INODE_UNRM         = 1,    /* Undelete */
 519         EXT4_INODE_COMPR        = 2,    /* Compress file */
 520         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 521         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 522         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 523         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 524         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 525 /* Reserved for compression usage... */
 526         EXT4_INODE_DIRTY        = 8,
 527         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 528         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 529         EXT4_INODE_ENCRYPT      = 11,   /* Encrypted file */
 530 /* End compression flags --- maybe not all used */
 531         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 532         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 533         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 534         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 535         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 536         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 537         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 538         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 539         EXT4_INODE_VERITY       = 20,   /* Verity protected inode */
 540         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 541 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
 542         EXT4_INODE_DAX          = 25,   /* Inode is DAX */
 543         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
 544         EXT4_INODE_PROJINHERIT  = 29,   /* Create with parents projid */
 545         EXT4_INODE_CASEFOLD     = 30,   /* Casefolded directory */
 546         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 547 };
 548
 549 /*
 550  * Since it's pretty easy to mix up bit numbers and hex values, we use a
 551  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
 552  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
 553  * any extra space in the compiled kernel image, otherwise, the build will fail.
 554  * It's important that these values are the same, since we are using
 555  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
 556  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
 557  * values found in ext2, ext3 and ext4 filesystems, and of course the values
 558  * defined in e2fsprogs.
 559  *
 560  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 561  */
 562 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 563 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
 564
 565 static inline void ext4_check_flag_values(void)
 566 {
 567         CHECK_FLAG_VALUE(SECRM);
 568         CHECK_FLAG_VALUE(UNRM);
 569         CHECK_FLAG_VALUE(COMPR);
 570         CHECK_FLAG_VALUE(SYNC);
 571         CHECK_FLAG_VALUE(IMMUTABLE);
 572         CHECK_FLAG_VALUE(APPEND);
 573         CHECK_FLAG_VALUE(NODUMP);
 574         CHECK_FLAG_VALUE(NOATIME);
 575         CHECK_FLAG_VALUE(DIRTY);
 576         CHECK_FLAG_VALUE(COMPRBLK);
 577         CHECK_FLAG_VALUE(NOCOMPR);
 578         CHECK_FLAG_VALUE(ENCRYPT);
 579         CHECK_FLAG_VALUE(INDEX);
 580         CHECK_FLAG_VALUE(IMAGIC);
 581         CHECK_FLAG_VALUE(JOURNAL_DATA);
 582         CHECK_FLAG_VALUE(NOTAIL);
 583         CHECK_FLAG_VALUE(DIRSYNC);
 584         CHECK_FLAG_VALUE(TOPDIR);
 585         CHECK_FLAG_VALUE(HUGE_FILE);
 586         CHECK_FLAG_VALUE(EXTENTS);
 587         CHECK_FLAG_VALUE(VERITY);
 588         CHECK_FLAG_VALUE(EA_INODE);
 589         CHECK_FLAG_VALUE(INLINE_DATA);
 590         CHECK_FLAG_VALUE(PROJINHERIT);
 591         CHECK_FLAG_VALUE(CASEFOLD);
 592         CHECK_FLAG_VALUE(RESERVED);
 593 }
 594
 595 /* Used to pass group descriptor data when online resize is done */
 596 struct ext4_new_group_input {
 597         __u32 group;            /* Group number for this data */
 598         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 599         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 600         __u64 inode_table;      /* Absolute block number of inode table start */
 601         __u32 blocks_count;     /* Total number of blocks in this group */
 602         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 603         __u16 unused;
 604 };
 605
 606 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 607 struct compat_ext4_new_group_input {
 608         u32 group;
 609         compat_u64 block_bitmap;
 610         compat_u64 inode_bitmap;
 611         compat_u64 inode_table;
 612         u32 blocks_count;
 613         u16 reserved_blocks;
 614         u16 unused;
 615 };
 616 #endif
 617
 618 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 619 struct ext4_new_group_data {
 620         __u32 group;
 621         __u64 block_bitmap;
 622         __u64 inode_bitmap;
 623         __u64 inode_table;
 624         __u32 blocks_count;
 625         __u16 reserved_blocks;
 626         __u16 mdata_blocks;
 627         __u32 free_clusters_count;
 628 };
 629
 630 /* Indexes used to index group tables in ext4_new_group_data */
 631 enum {
 632         BLOCK_BITMAP = 0,       /* block bitmap */
 633         INODE_BITMAP,           /* inode bitmap */
 634         INODE_TABLE,            /* inode tables */
 635         GROUP_TABLE_COUNT,
 636 };
 637
 638 /*
 639  * Flags used by ext4_map_blocks()
 640  */
 641         /* Allocate any needed blocks and/or convert an unwritten
 642            extent to be an initialized ext4 */
 643 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 644         /* Request the creation of an unwritten extent */
 645 #define EXT4_GET_BLOCKS_UNWRIT_EXT              0x0002
 646 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT       (EXT4_GET_BLOCKS_UNWRIT_EXT|\
 647                                                  EXT4_GET_BLOCKS_CREATE)
 648         /* Caller is from the delayed allocation writeout path
 649          * finally doing the actual allocation of delayed blocks */
 650 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 651         /* caller is from the direct IO path, request to creation of an
 652         unwritten extents if not allocated, split the unwritten
 653         extent if blocks has been preallocated already*/
 654 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 655 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 656 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 657                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 658         /* Convert extent to initialized after IO complete */
 659 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 660                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 661         /* Eventual metadata allocation (due to growing extent tree)
 662          * should not fail, so try to use reserved blocks for that.*/
 663 #define EXT4_GET_BLOCKS_METADATA_NOFAIL         0x0020
 664         /* Don't normalize allocation size (used for fallocate) */
 665 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 666         /* Convert written extents to unwritten */
 667 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN       0x0100
 668         /* Write zeros to newly created written extents */
 669 #define EXT4_GET_BLOCKS_ZERO                    0x0200
 670 #define EXT4_GET_BLOCKS_CREATE_ZERO             (EXT4_GET_BLOCKS_CREATE |\
 671                                         EXT4_GET_BLOCKS_ZERO)
 672         /* Caller will submit data before dropping transaction handle. This
 673          * allows jbd2 to avoid submitting data before commit. */
 674 #define EXT4_GET_BLOCKS_IO_SUBMIT               0x0400
 675
 676 /*
 677  * The bit position of these flags must not overlap with any of the
 678  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
 679  * read_extent_tree_block(), ext4_split_extent_at(),
 680  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
 681  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
 682  * caching the extents when reading from the extent tree while a
 683  * truncate or punch hole operation is in progress.
 684  */
 685 #define EXT4_EX_NOCACHE                         0x40000000
 686 #define EXT4_EX_FORCE_CACHE                     0x20000000
 687 #define EXT4_EX_NOFAIL                          0x10000000
 688
 689 /*
 690  * Flags used by ext4_free_blocks
 691  */
 692 #define EXT4_FREE_BLOCKS_METADATA               0x0001
 693 #define EXT4_FREE_BLOCKS_FORGET                 0x0002
 694 #define EXT4_FREE_BLOCKS_VALIDATED              0x0004
 695 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE         0x0008
 696 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 697 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 698 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
 699
 700 /*
 701  * ioctl commands
 702  */
 703 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 704 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 705 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 706 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 707 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 708 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 709 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 710 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 711 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 712  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 713  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 714 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 715 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 716 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 717 #define EXT4_IOC_SWAP_BOOT              _IO('f', 17)
 718 #define EXT4_IOC_PRECACHE_EXTENTS       _IO('f', 18)
 719 /* ioctl codes 19--39 are reserved for fscrypt */
 720 #define EXT4_IOC_CLEAR_ES_CACHE         _IO('f', 40)
 721 #define EXT4_IOC_GETSTATE               _IOW('f', 41, __u32)
 722 #define EXT4_IOC_GET_ES_CACHE           _IOWR('f', 42, struct fiemap)
 723 #define EXT4_IOC_CHECKPOINT             _IOW('f', 43, __u32)
 724
 725 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
 726
 727 /*
 728  * Flags for going down operation
 729  */
 730 #define EXT4_GOING_FLAGS_DEFAULT                0x0     /* going down */
 731 #define EXT4_GOING_FLAGS_LOGFLUSH               0x1     /* flush log but not data */
 732 #define EXT4_GOING_FLAGS_NOLOGFLUSH             0x2     /* don't flush log nor data */
 733
 734 /*
 735  * Flags returned by EXT4_IOC_GETSTATE
 736  *
 737  * We only expose to userspace a subset of the state flags in
 738  * i_state_flags
 739  */
 740 #define EXT4_STATE_FLAG_EXT_PRECACHED   0x00000001
 741 #define EXT4_STATE_FLAG_NEW             0x00000002
 742 #define EXT4_STATE_FLAG_NEWENTRY        0x00000004
 743 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE  0x00000008
 744
 745 /* flags for ioctl EXT4_IOC_CHECKPOINT */
 746 #define EXT4_IOC_CHECKPOINT_FLAG_DISCARD        0x1
 747 #define EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT        0x2
 748 #define EXT4_IOC_CHECKPOINT_FLAG_DRY_RUN        0x4
 749 #define EXT4_IOC_CHECKPOINT_FLAG_VALID          (EXT4_IOC_CHECKPOINT_FLAG_DISCARD | \
 750                                                 EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT | \
 751                                                 EXT4_IOC_CHECKPOINT_FLAG_DRY_RUN)
 752
 753 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 754 /*
 755  * ioctl commands in 32 bit emulation
 756  */
 757 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 758 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 759 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 760 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 761 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 762 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 763 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 764 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 765 #endif
 766
 767 /*
 768  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
 769  * It indicates that the entry in extent status cache is for a hole.
 770  */
 771 #define EXT4_FIEMAP_EXTENT_HOLE         0x08000000
 772
 773 /* Max physical block we can address w/o extents */
 774 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 775
 776 /* Max logical block we can support */
 777 #define EXT4_MAX_LOGICAL_BLOCK          0xFFFFFFFE
 778
 779 /*
 780  * Structure of an inode on the disk
 781  */
 782 struct ext4_inode {
 783         __le16  i_mode;         /* File mode */
 784         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 785         __le32  i_size_lo;      /* Size in bytes */
 786         __le32  i_atime;        /* Access time */
 787         __le32  i_ctime;        /* Inode Change time */
 788         __le32  i_mtime;        /* Modification time */
 789         __le32  i_dtime;        /* Deletion Time */
 790         __le16  i_gid;          /* Low 16 bits of Group Id */
 791         __le16  i_links_count;  /* Links count */
 792         __le32  i_blocks_lo;    /* Blocks count */
 793         __le32  i_flags;        /* File flags */
 794         union {
 795                 struct {
 796                         __le32  l_i_version;
 797                 } linux1;
 798                 struct {
 799                         __u32  h_i_translator;
 800                 } hurd1;
 801                 struct {
 802                         __u32  m_i_reserved1;
 803                 } masix1;
 804         } osd1;                         /* OS dependent 1 */
 805         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 806         __le32  i_generation;   /* File version (for NFS) */
 807         __le32  i_file_acl_lo;  /* File ACL */
 808         __le32  i_size_high;
 809         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 810         union {
 811                 struct {
 812                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 813                         __le16  l_i_file_acl_high;
 814                         __le16  l_i_uid_high;   /* these 2 fields */
 815                         __le16  l_i_gid_high;   /* were reserved2[0] */
 816                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 817                         __le16  l_i_reserved;
 818                 } linux2;
 819                 struct {
 820                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 821                         __u16   h_i_mode_high;
 822                         __u16   h_i_uid_high;
 823                         __u16   h_i_gid_high;
 824                         __u32   h_i_author;
 825                 } hurd2;
 826                 struct {
 827                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 828                         __le16  m_i_file_acl_high;
 829                         __u32   m_i_reserved2[2];
 830                 } masix2;
 831         } osd2;                         /* OS dependent 2 */
 832         __le16  i_extra_isize;
 833         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 834         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 835         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 836         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 837         __le32  i_crtime;       /* File Creation time */
 838         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 839         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 840         __le32  i_projid;       /* Project ID */
 841 };
 842
 843 struct move_extent {
 844         __u32 reserved;         /* should be zero */
 845         __u32 donor_fd;         /* donor file descriptor */
 846         __u64 orig_start;       /* logical start offset in block for orig */
 847         __u64 donor_start;      /* logical start offset in block for donor */
 848         __u64 len;              /* block length to be moved */
 849         __u64 moved_len;        /* moved block length */
 850 };
 851
 852 #define EXT4_EPOCH_BITS 2
 853 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 854 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 855
 856 /*
 857  * Extended fields will fit into an inode if the filesystem was formatted
 858  * with large inodes (-I 256 or larger) and there are not currently any EAs
 859  * consuming all of the available space. For new inodes we always reserve
 860  * enough space for the kernel's known extended fields, but for inodes
 861  * created with an old kernel this might not have been the case. None of
 862  * the extended inode fields is critical for correct filesystem operation.
 863  * This macro checks if a certain field fits in the inode. Note that
 864  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 865  */
 866 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 867         ((offsetof(typeof(*ext4_inode), field) +        \
 868           sizeof((ext4_inode)->field))                  \
 869         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 870             (einode)->i_extra_isize))                   \
 871
 872 /*
 873  * We use an encoding that preserves the times for extra epoch "00":
 874  *
 875  * extra  msb of                         adjust for signed
 876  * epoch  32-bit                         32-bit tv_sec to
 877  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
 878  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
 879  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
 880  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
 881  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
 882  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
 883  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
 884  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
 885  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
 886  *
 887  * Note that previous versions of the kernel on 64-bit systems would
 888  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
 889  * 1970.  e2fsck will correct this, assuming that it is run on the
 890  * affected filesystem before 2242.
 891  */
 892
 893 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
 894 {
 895         u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
 896         return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
 897 }
 898
 899 static inline void ext4_decode_extra_time(struct timespec64 *time,
 900                                           __le32 extra)
 901 {
 902         if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
 903                 time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
 904         time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 905 }
 906
 907 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                           \
 908 do {                                                                            \
 909         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
 910                 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);        \
 911                 (raw_inode)->xtime ## _extra =                                  \
 912                                 ext4_encode_extra_time(&(inode)->xtime);        \
 913                 }                                                               \
 914         else    \
 915                 (raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));    \
 916 } while (0)
 917
 918 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 919 do {                                                                           \
 920         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 921                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 922         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 923                 (raw_inode)->xtime ## _extra =                                 \
 924                                 ext4_encode_extra_time(&(einode)->xtime);      \
 925 } while (0)
 926
 927 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                           \
 928 do {                                                                            \
 929         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);        \
 930         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {    \
 931                 ext4_decode_extra_time(&(inode)->xtime,                         \
 932                                        raw_inode->xtime ## _extra);             \
 933                 }                                                               \
 934         else                                                                    \
 935                 (inode)->xtime.tv_nsec = 0;                                     \
 936 } while (0)
 937
 938
 939 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 940 do {                                                                           \
 941         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 942                 (einode)->xtime.tv_sec =                                       \
 943                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 944         else                                                                   \
 945                 (einode)->xtime.tv_sec = 0;                                    \
 946         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 947                 ext4_decode_extra_time(&(einode)->xtime,                       \
 948                                        raw_inode->xtime ## _extra);            \
 949         else                                                                   \
 950                 (einode)->xtime.tv_nsec = 0;                                   \
 951 } while (0)
 952
 953 #define i_disk_version osd1.linux1.l_i_version
 954
 955 #if defined(__KERNEL__) || defined(__linux__)
 956 #define i_reserved1     osd1.linux1.l_i_reserved1
 957 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 958 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 959 #define i_uid_low       i_uid
 960 #define i_gid_low       i_gid
 961 #define i_uid_high      osd2.linux2.l_i_uid_high
 962 #define i_gid_high      osd2.linux2.l_i_gid_high
 963 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 964
 965 #elif defined(__GNU__)
 966
 967 #define i_translator    osd1.hurd1.h_i_translator
 968 #define i_uid_high      osd2.hurd2.h_i_uid_high
 969 #define i_gid_high      osd2.hurd2.h_i_gid_high
 970 #define i_author        osd2.hurd2.h_i_author
 971
 972 #elif defined(__masix__)
 973
 974 #define i_reserved1     osd1.masix1.m_i_reserved1
 975 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 976 #define i_reserved2     osd2.masix2.m_i_reserved2
 977
 978 #endif /* defined(__KERNEL__) || defined(__linux__) */
 979
 980 #include "extents_status.h"
 981 #include "fast_commit.h"
 982
 983 /*
 984  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
 985  *
 986  * These are needed to avoid lockdep false positives when we need to
 987  * allocate blocks to the quota inode during ext4_map_blocks(), while
 988  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
 989  * do quota tracking for the quota inode, this avoids deadlock (as
 990  * well as infinite recursion, since it isn't turtles all the way
 991  * down...)
 992  *
 993  *  I_DATA_SEM_NORMAL - Used for most inodes
 994  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
 995  *                        where the second inode has larger inode number
 996  *                        than the first
 997  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
 998  */
 999 enum {
1000         I_DATA_SEM_NORMAL = 0,
1001         I_DATA_SEM_OTHER,
1002         I_DATA_SEM_QUOTA,
1003 };
1004
1005
1006 /*
1007  * fourth extended file system inode data in memory
1008  */
1009 struct ext4_inode_info {
1010         __le32  i_data[15];     /* unconverted */
1011         __u32   i_dtime;
1012         ext4_fsblk_t    i_file_acl;
1013
1014         /*
1015          * i_block_group is the number of the block group which contains
1016          * this file's inode.  Constant across the lifetime of the inode,
1017          * it is used for making block allocation decisions - we try to
1018          * place a file's data blocks near its inode block, and new inodes
1019          * near to their parent directory's inode.
1020          */
1021         ext4_group_t    i_block_group;
1022         ext4_lblk_t     i_dir_start_lookup;
1023 #if (BITS_PER_LONG < 64)
1024         unsigned long   i_state_flags;          /* Dynamic state flags */
1025 #endif
1026         unsigned long   i_flags;
1027
1028         /*
1029          * Extended attributes can be read independently of the main file
1030          * data. Taking i_mutex even when reading would cause contention
1031          * between readers of EAs and writers of regular file data, so
1032          * instead we synchronize on xattr_sem when reading or changing
1033          * EAs.
1034          */
1035         struct rw_semaphore xattr_sem;
1036
1037         struct list_head i_orphan;      /* unlinked but open inodes */
1038
1039         /* Fast commit related info */
1040
1041         struct list_head i_fc_list;     /*
1042                                          * inodes that need fast commit
1043                                          * protected by sbi->s_fc_lock.
1044                                          */
1045
1046         /* Start of lblk range that needs to be committed in this fast commit */
1047         ext4_lblk_t i_fc_lblk_start;
1048
1049         /* End of lblk range that needs to be committed in this fast commit */
1050         ext4_lblk_t i_fc_lblk_len;
1051
1052         /* Number of ongoing updates on this inode */
1053         atomic_t  i_fc_updates;
1054
1055         /* Fast commit wait queue for this inode */
1056         wait_queue_head_t i_fc_wait;
1057
1058         /* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
1059         struct mutex i_fc_lock;
1060
1061         /*
1062          * i_disksize keeps track of what the inode size is ON DISK, not
1063          * in memory.  During truncate, i_size is set to the new size by
1064          * the VFS prior to calling ext4_truncate(), but the filesystem won't
1065          * set i_disksize to 0 until the truncate is actually under way.
1066          *
1067          * The intent is that i_disksize always represents the blocks which
1068          * are used by this file.  This allows recovery to restart truncate
1069          * on orphans if we crash during truncate.  We actually write i_disksize
1070          * into the on-disk inode when writing inodes out, instead of i_size.
1071          *
1072          * The only time when i_disksize and i_size may be different is when
1073          * a truncate is in progress.  The only things which change i_disksize
1074          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1075          */
1076         loff_t  i_disksize;
1077
1078         /*
1079          * i_data_sem is for serialising ext4_truncate() against
1080          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1081          * data tree are chopped off during truncate. We can't do that in
1082          * ext4 because whenever we perform intermediate commits during
1083          * truncate, the inode and all the metadata blocks *must* be in a
1084          * consistent state which allows truncation of the orphans to restart
1085          * during recovery.  Hence we must fix the get_block-vs-truncate race
1086          * by other means, so we have i_data_sem.
1087          */
1088         struct rw_semaphore i_data_sem;
1089         /*
1090          * i_mmap_sem is for serializing page faults with truncate / punch hole
1091          * operations. We have to make sure that new page cannot be faulted in
1092          * a section of the inode that is being punched. We cannot easily use
1093          * i_data_sem for this since we need protection for the whole punch
1094          * operation and i_data_sem ranks below transaction start so we have
1095          * to occasionally drop it.
1096          */
1097         struct rw_semaphore i_mmap_sem;
1098         struct inode vfs_inode;
1099         struct jbd2_inode *jinode;
1100
1101         spinlock_t i_raw_lock;  /* protects updates to the raw inode */
1102
1103         /*
1104          * File creation time. Its function is same as that of
1105          * struct timespec64 i_{a,c,m}time in the generic inode.
1106          */
1107         struct timespec64 i_crtime;
1108
1109         /* mballoc */
1110         atomic_t i_prealloc_active;
1111         struct list_head i_prealloc_list;
1112         spinlock_t i_prealloc_lock;
1113
1114         /* extents status tree */
1115         struct ext4_es_tree i_es_tree;
1116         rwlock_t i_es_lock;
1117         struct list_head i_es_list;
1118         unsigned int i_es_all_nr;       /* protected by i_es_lock */
1119         unsigned int i_es_shk_nr;       /* protected by i_es_lock */
1120         ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
1121                                            extents to shrink. Protected by
1122                                            i_es_lock  */
1123
1124         /* ialloc */
1125         ext4_group_t    i_last_alloc_group;
1126
1127         /* allocation reservation info for delalloc */
1128         /* In case of bigalloc, this refer to clusters rather than blocks */
1129         unsigned int i_reserved_data_blocks;
1130
1131         /* pending cluster reservations for bigalloc file systems */
1132         struct ext4_pending_tree i_pending_tree;
1133
1134         /* on-disk additional length */
1135         __u16 i_extra_isize;
1136
1137         /* Indicate the inline data space. */
1138         u16 i_inline_off;
1139         u16 i_inline_size;
1140
1141 #ifdef CONFIG_QUOTA
1142         /* quota space reservation, managed internally by quota code */
1143         qsize_t i_reserved_quota;
1144 #endif
1145
1146         /* Lock protecting lists below */
1147         spinlock_t i_completed_io_lock;
1148         /*
1149          * Completed IOs that need unwritten extents handling and have
1150          * transaction reserved
1151          */
1152         struct list_head i_rsv_conversion_list;
1153         struct work_struct i_rsv_conversion_work;
1154         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1155
1156         spinlock_t i_block_reservation_lock;
1157
1158         /*
1159          * Transactions that contain inode's metadata needed to complete
1160          * fsync and fdatasync, respectively.
1161          */
1162         tid_t i_sync_tid;
1163         tid_t i_datasync_tid;
1164
1165 #ifdef CONFIG_QUOTA
1166         struct dquot *i_dquot[MAXQUOTAS];
1167 #endif
1168
1169         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1170         __u32 i_csum_seed;
1171
1172         kprojid_t i_projid;
1173 };
1174
1175 /*
1176  * File system states
1177  */
1178 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
1179 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
1180 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
1181 #define EXT4_FC_REPLAY                  0x0020  /* Fast commit replay ongoing */
1182
1183 /*
1184  * Misc. filesystem flags
1185  */
1186 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
1187 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
1188 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
1189
1190 /*
1191  * Mount flags set via mount options or defaults
1192  */
1193 #define EXT4_MOUNT_NO_MBCACHE           0x00001 /* Do not use mbcache */
1194 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
1195 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
1196 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
1197 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
1198 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
1199 #define EXT4_MOUNT_ERRORS_MASK          0x00070
1200 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
1201 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
1202 #ifdef CONFIG_FS_DAX
1203 #define EXT4_MOUNT_DAX_ALWAYS           0x00200 /* Direct Access */
1204 #else
1205 #define EXT4_MOUNT_DAX_ALWAYS           0
1206 #endif
1207 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
1208 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
1209 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
1210 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
1211 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
1212 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
1213 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
1214 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
1215 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
1216 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
1217 #define EXT4_MOUNT_QUOTA                0x40000 /* Some quota option set */
1218 #define EXT4_MOUNT_USRQUOTA             0x80000 /* "old" user quota,
1219                                                  * enable enforcement for hidden
1220                                                  * quota files */
1221 #define EXT4_MOUNT_GRPQUOTA             0x100000 /* "old" group quota, enable
1222                                                   * enforcement for hidden quota
1223                                                   * files */
1224 #define EXT4_MOUNT_PRJQUOTA             0x200000 /* Enable project quota
1225                                                   * enforcement */
1226 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
1227 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
1228 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
1229 #define EXT4_MOUNT_WARN_ON_ERROR        0x2000000 /* Trigger WARN_ON on error */
1230 #define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
1231 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
1232 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
1233 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
1234 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
1235 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
1236
1237 /*
1238  * Mount flags set either automatically (could not be set by mount option)
1239  * based on per file system feature or property or in special cases such as
1240  * distinguishing between explicit mount option definition and default.
1241  */
1242 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1243                                                       specified delalloc */
1244 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
1245                                                       size of blocksize * 8
1246                                                       blocks */
1247 #define EXT4_MOUNT2_HURD_COMPAT         0x00000004 /* Support HURD-castrated
1248                                                       file systems */
1249 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM   0x00000008 /* User explicitly
1250                                                 specified journal checksum */
1251
1252 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT 0x00000010 /* Journal fast commit */
1253 #define EXT4_MOUNT2_DAX_NEVER           0x00000020 /* Do not allow Direct Access */
1254 #define EXT4_MOUNT2_DAX_INODE           0x00000040 /* For printing options only */
1255 #define EXT4_MOUNT2_MB_OPTIMIZE_SCAN    0x00000080 /* Optimize group
1256                                                     * scanning in mballoc
1257                                                     */
1258
1259 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1260                                                 ~EXT4_MOUNT_##opt
1261 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1262                                                 EXT4_MOUNT_##opt
1263 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1264                                          EXT4_MOUNT_##opt)
1265
1266 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1267                                                 ~EXT4_MOUNT2_##opt
1268 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1269                                                 EXT4_MOUNT2_##opt
1270 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1271                                          EXT4_MOUNT2_##opt)
1272
1273 #define ext4_test_and_set_bit           __test_and_set_bit_le
1274 #define ext4_set_bit                    __set_bit_le
1275 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1276 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1277 #define ext4_clear_bit                  __clear_bit_le
1278 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1279 #define ext4_test_bit                   test_bit_le
1280 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1281 #define ext4_find_next_bit              find_next_bit_le
1282
1283 extern void ext4_set_bits(void *bm, int cur, int len);
1284
1285 /*
1286  * Maximal mount counts between two filesystem checks
1287  */
1288 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1289 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1290
1291 /*
1292  * Behaviour when detecting errors
1293  */
1294 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1295 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1296 #define EXT4_ERRORS_PANIC               3       /* Panic */
1297 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1298
1299 /* Metadata checksum algorithm codes */
1300 #define EXT4_CRC32C_CHKSUM              1
1301
1302 /*
1303  * Structure of the super block
1304  */
1305 struct ext4_super_block {
1306 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1307         __le32  s_blocks_count_lo;      /* Blocks count */
1308         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1309         __le32  s_free_blocks_count_lo; /* Free blocks count */
1310 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1311         __le32  s_first_data_block;     /* First Data Block */
1312         __le32  s_log_block_size;       /* Block size */
1313         __le32  s_log_cluster_size;     /* Allocation cluster size */
1314 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1315         __le32  s_clusters_per_group;   /* # Clusters per group */
1316         __le32  s_inodes_per_group;     /* # Inodes per group */
1317         __le32  s_mtime;                /* Mount time */
1318 /*30*/  __le32  s_wtime;                /* Write time */
1319         __le16  s_mnt_count;            /* Mount count */
1320         __le16  s_max_mnt_count;        /* Maximal mount count */
1321         __le16  s_magic;                /* Magic signature */
1322         __le16  s_state;                /* File system state */
1323         __le16  s_errors;               /* Behaviour when detecting errors */
1324         __le16  s_minor_rev_level;      /* minor revision level */
1325 /*40*/  __le32  s_lastcheck;            /* time of last check */
1326         __le32  s_checkinterval;        /* max. time between checks */
1327         __le32  s_creator_os;           /* OS */
1328         __le32  s_rev_level;            /* Revision level */
1329 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1330         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1331         /*
1332          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1333          *
1334          * Note: the difference between the compatible feature set and
1335          * the incompatible feature set is that if there is a bit set
1336          * in the incompatible feature set that the kernel doesn't
1337          * know about, it should refuse to mount the filesystem.
1338          *
1339          * e2fsck's requirements are more strict; if it doesn't know
1340          * about a feature in either the compatible or incompatible
1341          * feature set, it must abort and not try to meddle with
1342          * things it doesn't understand...
1343          */
1344         __le32  s_first_ino;            /* First non-reserved inode */
1345         __le16  s_inode_size;           /* size of inode structure */
1346         __le16  s_block_group_nr;       /* block group # of this superblock */
1347         __le32  s_feature_compat;       /* compatible feature set */
1348 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1349         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1350 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1351 /*78*/  char    s_volume_name[16];      /* volume name */
1352 /*88*/  char    s_last_mounted[64] __nonstring; /* directory where last mounted */
1353 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1354         /*
1355          * Performance hints.  Directory preallocation should only
1356          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1357          */
1358         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1359         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1360         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1361         /*
1362          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1363          */
1364 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1365 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1366         __le32  s_journal_dev;          /* device number of journal file */
1367         __le32  s_last_orphan;          /* start of list of inodes to delete */
1368         __le32  s_hash_seed[4];         /* HTREE hash seed */
1369         __u8    s_def_hash_version;     /* Default hash version to use */
1370         __u8    s_jnl_backup_type;
1371         __le16  s_desc_size;            /* size of group descriptor */
1372 /*100*/ __le32  s_default_mount_opts;
1373         __le32  s_first_meta_bg;        /* First metablock block group */
1374         __le32  s_mkfs_time;            /* When the filesystem was created */
1375         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1376         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1377 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1378         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1379         __le32  s_free_blocks_count_hi; /* Free blocks count */
1380         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1381         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1382         __le32  s_flags;                /* Miscellaneous flags */
1383         __le16  s_raid_stride;          /* RAID stride */
1384         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1385         __le64  s_mmp_block;            /* Block for multi-mount protection */
1386         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1387         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1388         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1389         __u8    s_encryption_level;     /* versioning level for encryption */
1390         __u8    s_reserved_pad;         /* Padding to next 32bits */
1391         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1392         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1393         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1394         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1395                                               snapshot's future use */
1396         __le32  s_snapshot_list;        /* inode number of the head of the
1397                                            on-disk snapshot list */
1398 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1399         __le32  s_error_count;          /* number of fs errors */
1400         __le32  s_first_error_time;     /* first time an error happened */
1401         __le32  s_first_error_ino;      /* inode involved in first error */
1402         __le64  s_first_error_block;    /* block involved of first error */
1403         __u8    s_first_error_func[32] __nonstring;     /* function where the error happened */
1404         __le32  s_first_error_line;     /* line number where error happened */
1405         __le32  s_last_error_time;      /* most recent time of an error */
1406         __le32  s_last_error_ino;       /* inode involved in last error */
1407         __le32  s_last_error_line;      /* line number where error happened */
1408         __le64  s_last_error_block;     /* block involved of last error */
1409         __u8    s_last_error_func[32] __nonstring;      /* function where the error happened */
1410 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1411         __u8    s_mount_opts[64];
1412         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1413         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1414         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1415         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
1416         __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
1417         __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
1418         __le32  s_lpf_ino;              /* Location of the lost+found inode */
1419         __le32  s_prj_quota_inum;       /* inode for tracking project quota */
1420         __le32  s_checksum_seed;        /* crc32c(uuid) if csum_seed set */
1421         __u8    s_wtime_hi;
1422         __u8    s_mtime_hi;
1423         __u8    s_mkfs_time_hi;
1424         __u8    s_lastcheck_hi;
1425         __u8    s_first_error_time_hi;
1426         __u8    s_last_error_time_hi;
1427         __u8    s_first_error_errcode;
1428         __u8    s_last_error_errcode;
1429         __le16  s_encoding;             /* Filename charset encoding */
1430         __le16  s_encoding_flags;       /* Filename charset encoding flags */
1431         __le32  s_reserved[95];         /* Padding to the end of the block */
1432         __le32  s_checksum;             /* crc32c(superblock) */
1433 };
1434
1435 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1436
1437 #ifdef __KERNEL__
1438
1439 #ifdef CONFIG_FS_ENCRYPTION
1440 #define DUMMY_ENCRYPTION_ENABLED(sbi) ((sbi)->s_dummy_enc_policy.policy != NULL)
1441 #else
1442 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1443 #endif
1444
1445 /* Number of quota types we support */
1446 #define EXT4_MAXQUOTAS 3
1447
1448 #define EXT4_ENC_UTF8_12_1      1
1449
1450 /*
1451  * fourth extended-fs super-block data in memory
1452  */
1453 struct ext4_sb_info {
1454         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1455         unsigned long s_inodes_per_block;/* Number of inodes per block */
1456         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1457         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1458         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1459         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1460         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1461         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1462         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1463         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1464         unsigned long s_overhead;  /* # of fs overhead clusters */
1465         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1466         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1467         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1468         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1469         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1470         struct buffer_head * __rcu *s_group_desc;
1471         unsigned int s_mount_opt;
1472         unsigned int s_mount_opt2;
1473         unsigned long s_mount_flags;
1474         unsigned int s_def_mount_opt;
1475         ext4_fsblk_t s_sb_block;
1476         atomic64_t s_resv_clusters;
1477         kuid_t s_resuid;
1478         kgid_t s_resgid;
1479         unsigned short s_mount_state;
1480         unsigned short s_pad;
1481         int s_addr_per_block_bits;
1482         int s_desc_per_block_bits;
1483         int s_inode_size;
1484         int s_first_ino;
1485         unsigned int s_inode_readahead_blks;
1486         unsigned int s_inode_goal;
1487         u32 s_hash_seed[4];
1488         int s_def_hash_version;
1489         int s_hash_unsigned;    /* 3 if hash should be unsigned, 0 if not */
1490         struct percpu_counter s_freeclusters_counter;
1491         struct percpu_counter s_freeinodes_counter;
1492         struct percpu_counter s_dirs_counter;
1493         struct percpu_counter s_dirtyclusters_counter;
1494         struct percpu_counter s_sra_exceeded_retry_limit;
1495         struct blockgroup_lock *s_blockgroup_lock;
1496         struct proc_dir_entry *s_proc;
1497         struct kobject s_kobj;
1498         struct completion s_kobj_unregister;
1499         struct super_block *s_sb;
1500         struct buffer_head *s_mmp_bh;
1501
1502         /* Journaling */
1503         struct journal_s *s_journal;
1504         struct list_head s_orphan;
1505         struct mutex s_orphan_lock;
1506         unsigned long s_ext4_flags;             /* Ext4 superblock flags */
1507         unsigned long s_commit_interval;
1508         u32 s_max_batch_time;
1509         u32 s_min_batch_time;
1510         struct block_device *s_journal_bdev;
1511 #ifdef CONFIG_QUOTA
1512         /* Names of quota files with journalled quota */
1513         char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1514         int s_jquota_fmt;                       /* Format of quota to use */
1515 #endif
1516         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1517         struct ext4_system_blocks __rcu *s_system_blks;
1518
1519 #ifdef EXTENTS_STATS
1520         /* ext4 extents stats */
1521         unsigned long s_ext_min;
1522         unsigned long s_ext_max;
1523         unsigned long s_depth_max;
1524         spinlock_t s_ext_stats_lock;
1525         unsigned long s_ext_blocks;
1526         unsigned long s_ext_extents;
1527 #endif
1528
1529         /* for buddy allocator */
1530         struct ext4_group_info ** __rcu *s_group_info;
1531         struct inode *s_buddy_cache;
1532         spinlock_t s_md_lock;
1533         unsigned short *s_mb_offsets;
1534         unsigned int *s_mb_maxs;
1535         unsigned int s_group_info_size;
1536         unsigned int s_mb_free_pending;
1537         struct list_head s_freed_data_list;     /* List of blocks to be freed
1538                                                    after commit completed */
1539         struct list_head s_discard_list;
1540         struct work_struct s_discard_work;
1541         atomic_t s_retry_alloc_pending;
1542         struct rb_root s_mb_avg_fragment_size_root;
1543         rwlock_t s_mb_rb_lock;
1544         struct list_head *s_mb_largest_free_orders;
1545         rwlock_t *s_mb_largest_free_orders_locks;
1546
1547         /* tunables */
1548         unsigned long s_stripe;
1549         unsigned int s_mb_max_linear_groups;
1550         unsigned int s_mb_stream_request;
1551         unsigned int s_mb_max_to_scan;
1552         unsigned int s_mb_min_to_scan;
1553         unsigned int s_mb_stats;
1554         unsigned int s_mb_order2_reqs;
1555         unsigned int s_mb_group_prealloc;
1556         unsigned int s_mb_max_inode_prealloc;
1557         unsigned int s_max_dir_size_kb;
1558         /* where last allocation was done - for stream allocation */
1559         unsigned long s_mb_last_group;
1560         unsigned long s_mb_last_start;
1561         unsigned int s_mb_prefetch;
1562         unsigned int s_mb_prefetch_limit;
1563
1564         /* stats for buddy allocator */
1565         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1566         atomic_t s_bal_success; /* we found long enough chunks */
1567         atomic_t s_bal_allocated;       /* in blocks */
1568         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1569         atomic_t s_bal_groups_scanned;  /* number of groups scanned */
1570         atomic_t s_bal_goals;   /* goal hits */
1571         atomic_t s_bal_breaks;  /* too long searches */
1572         atomic_t s_bal_2orders; /* 2^order hits */
1573         atomic_t s_bal_cr0_bad_suggestions;
1574         atomic_t s_bal_cr1_bad_suggestions;
1575         atomic64_t s_bal_cX_groups_considered[4];
1576         atomic64_t s_bal_cX_hits[4];
1577         atomic64_t s_bal_cX_failed[4];          /* cX loop didn't find blocks */
1578         atomic_t s_mb_buddies_generated;        /* number of buddies generated */
1579         atomic64_t s_mb_generation_time;
1580         atomic_t s_mb_lost_chunks;
1581         atomic_t s_mb_preallocated;
1582         atomic_t s_mb_discarded;
1583         atomic_t s_lock_busy;
1584
1585         /* locality groups */
1586         struct ext4_locality_group __percpu *s_locality_groups;
1587
1588         /* for write statistics */
1589         unsigned long s_sectors_written_start;
1590         u64 s_kbytes_written;
1591
1592         /* the size of zero-out chunk */
1593         unsigned int s_extent_max_zeroout_kb;
1594
1595         unsigned int s_log_groups_per_flex;
1596         struct flex_groups * __rcu *s_flex_groups;
1597         ext4_group_t s_flex_groups_allocated;
1598
1599         /* workqueue for reserved extent conversions (buffered io) */
1600         struct workqueue_struct *rsv_conversion_wq;
1601
1602         /* timer for periodic error stats printing */
1603         struct timer_list s_err_report;
1604
1605         /* Lazy inode table initialization info */
1606         struct ext4_li_request *s_li_request;
1607         /* Wait multiplier for lazy initialization thread */
1608         unsigned int s_li_wait_mult;
1609
1610         /* Kernel thread for multiple mount protection */
1611         struct task_struct *s_mmp_tsk;
1612
1613         /* record the last minlen when FITRIM is called. */
1614         atomic_t s_last_trim_minblks;
1615
1616         /* Reference to checksum algorithm driver via cryptoapi */
1617         struct crypto_shash *s_chksum_driver;
1618
1619         /* Precomputed FS UUID checksum for seeding other checksums */
1620         __u32 s_csum_seed;
1621
1622         /* Reclaim extents from extent status tree */
1623         struct shrinker s_es_shrinker;
1624         struct list_head s_es_list;     /* List of inodes with reclaimable extents */
1625         long s_es_nr_inode;
1626         struct ext4_es_stats s_es_stats;
1627         struct mb_cache *s_ea_block_cache;
1628         struct mb_cache *s_ea_inode_cache;
1629         spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1630
1631         /* Ratelimit ext4 messages. */
1632         struct ratelimit_state s_err_ratelimit_state;
1633         struct ratelimit_state s_warning_ratelimit_state;
1634         struct ratelimit_state s_msg_ratelimit_state;
1635         atomic_t s_warning_count;
1636         atomic_t s_msg_count;
1637
1638         /* Encryption policy for '-o test_dummy_encryption' */
1639         struct fscrypt_dummy_policy s_dummy_enc_policy;
1640
1641         /*
1642          * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1643          * or EXTENTS flag.
1644          */
1645         struct percpu_rw_semaphore s_writepages_rwsem;
1646         struct dax_device *s_daxdev;
1647 #ifdef CONFIG_EXT4_DEBUG
1648         unsigned long s_simulate_fail;
1649 #endif
1650         /* Record the errseq of the backing block device */
1651         errseq_t s_bdev_wb_err;
1652         spinlock_t s_bdev_wb_lock;
1653
1654         /* Information about errors that happened during this mount */
1655         spinlock_t s_error_lock;
1656         int s_add_error_count;
1657         int s_first_error_code;
1658         __u32 s_first_error_line;
1659         __u32 s_first_error_ino;
1660         __u64 s_first_error_block;
1661         const char *s_first_error_func;
1662         time64_t s_first_error_time;
1663         int s_last_error_code;
1664         __u32 s_last_error_line;
1665         __u32 s_last_error_ino;
1666         __u64 s_last_error_block;
1667         const char *s_last_error_func;
1668         time64_t s_last_error_time;
1669         /*
1670          * If we are in a context where we cannot update error information in
1671          * the on-disk superblock, we queue this work to do it.
1672          */
1673         struct work_struct s_error_work;
1674
1675         /* Ext4 fast commit stuff */
1676         atomic_t s_fc_subtid;
1677         atomic_t s_fc_ineligible_updates;
1678         /*
1679          * After commit starts, the main queue gets locked, and the further
1680          * updates get added in the staging queue.
1681          */
1682 #define FC_Q_MAIN       0
1683 #define FC_Q_STAGING    1
1684         struct list_head s_fc_q[2];     /* Inodes staged for fast commit
1685                                          * that have data changes in them.
1686                                          */
1687         struct list_head s_fc_dentry_q[2];      /* directory entry updates */
1688         unsigned int s_fc_bytes;
1689         /*
1690          * Main fast commit lock. This lock protects accesses to the
1691          * following fields:
1692          * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1693          */
1694         spinlock_t s_fc_lock;
1695         struct buffer_head *s_fc_bh;
1696         struct ext4_fc_stats s_fc_stats;
1697         u64 s_fc_avg_commit_time;
1698 #ifdef CONFIG_EXT4_DEBUG
1699         int s_fc_debug_max_replay;
1700 #endif
1701         struct ext4_fc_replay_state s_fc_replay_state;
1702 };
1703
1704 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1705 {
1706         return sb->s_fs_info;
1707 }
1708 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1709 {
1710         return container_of(inode, struct ext4_inode_info, vfs_inode);
1711 }
1712
1713 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1714 {
1715         return ino == EXT4_ROOT_INO ||
1716                 (ino >= EXT4_FIRST_INO(sb) &&
1717                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1718 }
1719
1720 /*
1721  * Returns: sbi->field[index]
1722  * Used to access an array element from the following sbi fields which require
1723  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1724  * - s_group_desc
1725  * - s_group_info
1726  * - s_flex_group
1727  */
1728 #define sbi_array_rcu_deref(sbi, field, index)                             \
1729 ({                                                                         \
1730         typeof(*((sbi)->field)) _v;                                        \
1731         rcu_read_lock();                                                   \
1732         _v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];          \
1733         rcu_read_unlock();                                                 \
1734         _v;                                                                \
1735 })
1736
1737 /*
1738  * run-time mount flags
1739  */
1740 enum {
1741         EXT4_MF_MNTDIR_SAMPLED,
1742         EXT4_MF_FS_ABORTED,     /* Fatal error detected */
1743         EXT4_MF_FC_INELIGIBLE,  /* Fast commit ineligible */
1744         EXT4_MF_FC_COMMITTING   /* File system underoing a fast
1745                                  * commit.
1746                                  */
1747 };
1748
1749 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
1750 {
1751         set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1752 }
1753
1754 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
1755 {
1756         clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1757 }
1758
1759 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
1760 {
1761         return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1762 }
1763
1764
1765 /*
1766  * Simulate_fail codes
1767  */
1768 #define EXT4_SIM_BBITMAP_EIO    1
1769 #define EXT4_SIM_BBITMAP_CRC    2
1770 #define EXT4_SIM_IBITMAP_EIO    3
1771 #define EXT4_SIM_IBITMAP_CRC    4
1772 #define EXT4_SIM_INODE_EIO      5
1773 #define EXT4_SIM_INODE_CRC      6
1774 #define EXT4_SIM_DIRBLOCK_EIO   7
1775 #define EXT4_SIM_DIRBLOCK_CRC   8
1776
1777 static inline bool ext4_simulate_fail(struct super_block *sb,
1778                                      unsigned long code)
1779 {
1780 #ifdef CONFIG_EXT4_DEBUG
1781         struct ext4_sb_info *sbi = EXT4_SB(sb);
1782
1783         if (unlikely(sbi->s_simulate_fail == code)) {
1784                 sbi->s_simulate_fail = 0;
1785                 return true;
1786         }
1787 #endif
1788         return false;
1789 }
1790
1791 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1792                                          struct buffer_head *bh,
1793                                          unsigned long code)
1794 {
1795         if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1796                 clear_buffer_uptodate(bh);
1797 }
1798
1799 /*
1800  * Error number codes for s_{first,last}_error_errno
1801  *
1802  * Linux errno numbers are architecture specific, so we need to translate
1803  * them into something which is architecture independent.   We don't define
1804  * codes for all errno's; just the ones which are most likely to be the cause
1805  * of an ext4_error() call.
1806  */
1807 #define EXT4_ERR_UNKNOWN         1
1808 #define EXT4_ERR_EIO             2
1809 #define EXT4_ERR_ENOMEM          3
1810 #define EXT4_ERR_EFSBADCRC       4
1811 #define EXT4_ERR_EFSCORRUPTED    5
1812 #define EXT4_ERR_ENOSPC          6
1813 #define EXT4_ERR_ENOKEY          7
1814 #define EXT4_ERR_EROFS           8
1815 #define EXT4_ERR_EFBIG           9
1816 #define EXT4_ERR_EEXIST         10
1817 #define EXT4_ERR_ERANGE         11
1818 #define EXT4_ERR_EOVERFLOW      12
1819 #define EXT4_ERR_EBUSY          13
1820 #define EXT4_ERR_ENOTDIR        14
1821 #define EXT4_ERR_ENOTEMPTY      15
1822 #define EXT4_ERR_ESHUTDOWN      16
1823 #define EXT4_ERR_EFAULT         17
1824
1825 /*
1826  * Inode dynamic state flags
1827  */
1828 enum {
1829         EXT4_STATE_JDATA,               /* journaled data exists */
1830         EXT4_STATE_NEW,                 /* inode is newly created */
1831         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1832         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1833         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1834         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1835         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1836         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1837         EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
1838         EXT4_STATE_LUSTRE_EA_INODE,     /* Lustre-style ea_inode */
1839         EXT4_STATE_VERITY_IN_PROGRESS,  /* building fs-verity Merkle tree */
1840         EXT4_STATE_FC_COMMITTING,       /* Fast commit ongoing */
1841 };
1842
1843 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1844 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1845 {                                                                       \
1846         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1847 }                                                                       \
1848 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1849 {                                                                       \
1850         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1851 }                                                                       \
1852 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1853 {                                                                       \
1854         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1855 }
1856
1857 /* Add these declarations here only so that these functions can be
1858  * found by name.  Otherwise, they are very hard to locate. */
1859 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1860 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1861 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1862 EXT4_INODE_BIT_FNS(flag, flags, 0)
1863
1864 /* Add these declarations here only so that these functions can be
1865  * found by name.  Otherwise, they are very hard to locate. */
1866 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1867 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1868 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1869 #if (BITS_PER_LONG < 64)
1870 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1871
1872 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1873 {
1874         (ei)->i_state_flags = 0;
1875 }
1876 #else
1877 EXT4_INODE_BIT_FNS(state, flags, 32)
1878
1879 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1880 {
1881         /* We depend on the fact that callers will set i_flags */
1882 }
1883 #endif
1884 #else
1885 /* Assume that user mode programs are passing in an ext4fs superblock, not
1886  * a kernel struct super_block.  This will allow us to call the feature-test
1887  * macros from user land. */
1888 #define EXT4_SB(sb)     (sb)
1889 #endif
1890
1891 static inline bool ext4_verity_in_progress(struct inode *inode)
1892 {
1893         return IS_ENABLED(CONFIG_FS_VERITY) &&
1894                ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1895 }
1896
1897 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1898
1899 /*
1900  * Codes for operating systems
1901  */
1902 #define EXT4_OS_LINUX           0
1903 #define EXT4_OS_HURD            1
1904 #define EXT4_OS_MASIX           2
1905 #define EXT4_OS_FREEBSD         3
1906 #define EXT4_OS_LITES           4
1907
1908 /*
1909  * Revision levels
1910  */
1911 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1912 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1913
1914 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1915
1916 #define EXT4_GOOD_OLD_INODE_SIZE 128
1917
1918 #define EXT4_EXTRA_TIMESTAMP_MAX        (((s64)1 << 34) - 1  + S32_MIN)
1919 #define EXT4_NON_EXTRA_TIMESTAMP_MAX    S32_MAX
1920 #define EXT4_TIMESTAMP_MIN              S32_MIN
1921
1922 /*
1923  * Feature set definitions
1924  */
1925
1926 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1927 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1928 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1929 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1930 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1931 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1932 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2       0x0200
1933 /*
1934  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
1935  * incompatible only if fast commit blocks are present in the FS. Since we
1936  * clear the journal (and thus the fast commit blocks), we don't mark FS as
1937  * incompatible. We also have a JBD2 incompat feature, which gets set when
1938  * there are fast commit blocks present in the journal.
1939  */
1940 #define EXT4_FEATURE_COMPAT_FAST_COMMIT         0x0400
1941 #define EXT4_FEATURE_COMPAT_STABLE_INODES       0x0800
1942
1943 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1944 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1945 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1946 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1947 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1948 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1949 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1950 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1951 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1952 /*
1953  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1954  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1955  * all other data structures' checksums.  However, the METADATA_CSUM and
1956  * GDT_CSUM bits are mutually exclusive.
1957  */
1958 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1959 #define EXT4_FEATURE_RO_COMPAT_READONLY         0x1000
1960 #define EXT4_FEATURE_RO_COMPAT_PROJECT          0x2000
1961 #define EXT4_FEATURE_RO_COMPAT_VERITY           0x8000
1962
1963 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1964 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1965 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1966 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1967 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1968 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1969 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1970 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1971 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1972 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1973 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1974 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED         0x2000
1975 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1976 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1977 #define EXT4_FEATURE_INCOMPAT_ENCRYPT           0x10000
1978 #define EXT4_FEATURE_INCOMPAT_CASEFOLD          0x20000
1979
1980 extern void ext4_update_dynamic_rev(struct super_block *sb);
1981
1982 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1983 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1984 { \
1985         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1986                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1987 } \
1988 static inline void ext4_set_feature_##name(struct super_block *sb) \
1989 { \
1990         ext4_update_dynamic_rev(sb); \
1991         EXT4_SB(sb)->s_es->s_feature_compat |= \
1992                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1993 } \
1994 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1995 { \
1996         EXT4_SB(sb)->s_es->s_feature_compat &= \
1997                 ~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1998 }
1999
2000 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
2001 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2002 { \
2003         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2004                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
2005 } \
2006 static inline void ext4_set_feature_##name(struct super_block *sb) \
2007 { \
2008         ext4_update_dynamic_rev(sb); \
2009         EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
2010                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2011 } \
2012 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2013 { \
2014         EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
2015                 ~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2016 }
2017
2018 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
2019 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2020 { \
2021         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2022                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
2023 } \
2024 static inline void ext4_set_feature_##name(struct super_block *sb) \
2025 { \
2026         ext4_update_dynamic_rev(sb); \
2027         EXT4_SB(sb)->s_es->s_feature_incompat |= \
2028                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2029 } \
2030 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2031 { \
2032         EXT4_SB(sb)->s_es->s_feature_incompat &= \
2033                 ~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2034 }
2035
2036 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,         DIR_PREALLOC)
2037 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,        IMAGIC_INODES)
2038 EXT4_FEATURE_COMPAT_FUNCS(journal,              HAS_JOURNAL)
2039 EXT4_FEATURE_COMPAT_FUNCS(xattr,                EXT_ATTR)
2040 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,         RESIZE_INODE)
2041 EXT4_FEATURE_COMPAT_FUNCS(dir_index,            DIR_INDEX)
2042 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,        SPARSE_SUPER2)
2043 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,          FAST_COMMIT)
2044 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,        STABLE_INODES)
2045
2046 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,      SPARSE_SUPER)
2047 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,        LARGE_FILE)
2048 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,         BTREE_DIR)
2049 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,         HUGE_FILE)
2050 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,          GDT_CSUM)
2051 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,         DIR_NLINK)
2052 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,       EXTRA_ISIZE)
2053 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,             QUOTA)
2054 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,          BIGALLOC)
2055 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,     METADATA_CSUM)
2056 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,          READONLY)
2057 EXT4_FEATURE_RO_COMPAT_FUNCS(project,           PROJECT)
2058 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,            VERITY)
2059
2060 EXT4_FEATURE_INCOMPAT_FUNCS(compression,        COMPRESSION)
2061 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,           FILETYPE)
2062 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,     RECOVER)
2063 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,        JOURNAL_DEV)
2064 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,            META_BG)
2065 EXT4_FEATURE_INCOMPAT_FUNCS(extents,            EXTENTS)
2066 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,              64BIT)
2067 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,                MMP)
2068 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,            FLEX_BG)
2069 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,           EA_INODE)
2070 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,            DIRDATA)
2071 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,          CSUM_SEED)
2072 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,           LARGEDIR)
2073 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,        INLINE_DATA)
2074 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,            ENCRYPT)
2075 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,           CASEFOLD)
2076
2077 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2078 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2079                                          EXT4_FEATURE_INCOMPAT_META_BG)
2080 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2081                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2082                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2083
2084 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2085 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2086                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
2087                                          EXT4_FEATURE_INCOMPAT_META_BG)
2088 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2089                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2090                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2091
2092 #define EXT4_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2093 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2094                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
2095                                          EXT4_FEATURE_INCOMPAT_META_BG| \
2096                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
2097                                          EXT4_FEATURE_INCOMPAT_64BIT| \
2098                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2099                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
2100                                          EXT4_FEATURE_INCOMPAT_MMP | \
2101                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2102                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2103                                          EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2104                                          EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2105                                          EXT4_FEATURE_INCOMPAT_LARGEDIR)
2106 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2107                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2108                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2109                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2110                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2111                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2112                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2113                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2114                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2115                                          EXT4_FEATURE_RO_COMPAT_QUOTA |\
2116                                          EXT4_FEATURE_RO_COMPAT_PROJECT |\
2117                                          EXT4_FEATURE_RO_COMPAT_VERITY)
2118
2119 #define EXTN_FEATURE_FUNCS(ver) \
2120 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2121 { \
2122         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2123                 cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2124 } \
2125 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2126 { \
2127         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2128                 cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2129 } \
2130 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2131 { \
2132         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2133                 cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2134 }
2135
2136 EXTN_FEATURE_FUNCS(2)
2137 EXTN_FEATURE_FUNCS(3)
2138 EXTN_FEATURE_FUNCS(4)
2139
2140 static inline bool ext4_has_compat_features(struct super_block *sb)
2141 {
2142         return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2143 }
2144 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2145 {
2146         return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2147 }
2148 static inline bool ext4_has_incompat_features(struct super_block *sb)
2149 {
2150         return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2151 }
2152
2153 /*
2154  * Superblock flags
2155  */
2156 #define EXT4_FLAGS_RESIZING     0
2157 #define EXT4_FLAGS_SHUTDOWN     1
2158 #define EXT4_FLAGS_BDEV_IS_DAX  2
2159
2160 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2161 {
2162         return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2163 }
2164
2165
2166 /*
2167  * Default values for user and/or group using reserved blocks
2168  */
2169 #define EXT4_DEF_RESUID         0
2170 #define EXT4_DEF_RESGID         0
2171
2172 /*
2173  * Default project ID
2174  */
2175 #define EXT4_DEF_PROJID         0
2176
2177 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
2178
2179 /*
2180  * Default mount options
2181  */
2182 #define EXT4_DEFM_DEBUG         0x0001
2183 #define EXT4_DEFM_BSDGROUPS     0x0002
2184 #define EXT4_DEFM_XATTR_USER    0x0004
2185 #define EXT4_DEFM_ACL           0x0008
2186 #define EXT4_DEFM_UID16         0x0010
2187 #define EXT4_DEFM_JMODE         0x0060
2188 #define EXT4_DEFM_JMODE_DATA    0x0020
2189 #define EXT4_DEFM_JMODE_ORDERED 0x0040
2190 #define EXT4_DEFM_JMODE_WBACK   0x0060
2191 #define EXT4_DEFM_NOBARRIER     0x0100
2192 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2193 #define EXT4_DEFM_DISCARD       0x0400
2194 #define EXT4_DEFM_NODELALLOC    0x0800
2195
2196 /*
2197  * Default journal batch times
2198  */
2199 #define EXT4_DEF_MIN_BATCH_TIME 0
2200 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
2201
2202 /*
2203  * Minimum number of groups in a flexgroup before we separate out
2204  * directories into the first block group of a flexgroup
2205  */
2206 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
2207
2208 /*
2209  * Structure of a directory entry
2210  */
2211 #define EXT4_NAME_LEN 255
2212
2213 struct ext4_dir_entry {
2214         __le32  inode;                  /* Inode number */
2215         __le16  rec_len;                /* Directory entry length */
2216         __le16  name_len;               /* Name length */
2217         char    name[EXT4_NAME_LEN];    /* File name */
2218 };
2219
2220
2221 /*
2222  * Encrypted Casefolded entries require saving the hash on disk. This structure
2223  * followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
2224  * boundary.
2225  */
2226 struct ext4_dir_entry_hash {
2227         __le32 hash;
2228         __le32 minor_hash;
2229 };
2230
2231 /*
2232  * The new version of the directory entry.  Since EXT4 structures are
2233  * stored in intel byte order, and the name_len field could never be
2234  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2235  * file_type field.
2236  */
2237 struct ext4_dir_entry_2 {
2238         __le32  inode;                  /* Inode number */
2239         __le16  rec_len;                /* Directory entry length */
2240         __u8    name_len;               /* Name length */
2241         __u8    file_type;              /* See file type macros EXT4_FT_* below */
2242         char    name[EXT4_NAME_LEN];    /* File name */
2243 };
2244
2245 /*
2246  * Access the hashes at the end of ext4_dir_entry_2
2247  */
2248 #define EXT4_DIRENT_HASHES(entry) \
2249         ((struct ext4_dir_entry_hash *) \
2250                 (((void *)(entry)) + \
2251                 ((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
2252 #define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(de)->hash)
2253 #define EXT4_DIRENT_MINOR_HASH(entry) \
2254                 le32_to_cpu(EXT4_DIRENT_HASHES(de)->minor_hash)
2255
2256 static inline bool ext4_hash_in_dirent(const struct inode *inode)
2257 {
2258         return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
2259 }
2260
2261 /*
2262  * This is a bogus directory entry at the end of each leaf block that
2263  * records checksums.
2264  */
2265 struct ext4_dir_entry_tail {
2266         __le32  det_reserved_zero1;     /* Pretend to be unused */
2267         __le16  det_rec_len;            /* 12 */
2268         __u8    det_reserved_zero2;     /* Zero name length */
2269         __u8    det_reserved_ft;        /* 0xDE, fake file type */
2270         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
2271 };
2272
2273 #define EXT4_DIRENT_TAIL(block, blocksize) \
2274         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2275                                         ((blocksize) - \
2276                                          sizeof(struct ext4_dir_entry_tail))))
2277
2278 /*
2279  * Ext4 directory file types.  Only the low 3 bits are used.  The
2280  * other bits are reserved for now.
2281  */
2282 #define EXT4_FT_UNKNOWN         0
2283 #define EXT4_FT_REG_FILE        1
2284 #define EXT4_FT_DIR             2
2285 #define EXT4_FT_CHRDEV          3
2286 #define EXT4_FT_BLKDEV          4
2287 #define EXT4_FT_FIFO            5
2288 #define EXT4_FT_SOCK            6
2289 #define EXT4_FT_SYMLINK         7
2290
2291 #define EXT4_FT_MAX             8
2292
2293 #define EXT4_FT_DIR_CSUM        0xDE
2294
2295 /*
2296  * EXT4_DIR_PAD defines the directory entries boundaries
2297  *
2298  * NOTE: It must be a multiple of 4
2299  */
2300 #define EXT4_DIR_PAD                    4
2301 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
2302 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
2303
2304 /*
2305  * The rec_len is dependent on the type of directory. Directories that are
2306  * casefolded and encrypted need to store the hash as well, so we add room for
2307  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
2308  * pass NULL for dir, as those entries do not use the extra fields.
2309  */
2310 static inline unsigned int ext4_dir_rec_len(__u8 name_len,
2311                                                 const struct inode *dir)
2312 {
2313         int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
2314
2315         if (dir && ext4_hash_in_dirent(dir))
2316                 rec_len += sizeof(struct ext4_dir_entry_hash);
2317         return (rec_len & ~EXT4_DIR_ROUND);
2318 }
2319
2320 /*
2321  * If we ever get support for fs block sizes > page_size, we'll need
2322  * to remove the #if statements in the next two functions...
2323  */
2324 static inline unsigned int
2325 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2326 {
2327         unsigned len = le16_to_cpu(dlen);
2328
2329 #if (PAGE_SIZE >= 65536)
2330         if (len == EXT4_MAX_REC_LEN || len == 0)
2331                 return blocksize;
2332         return (len & 65532) | ((len & 3) << 16);
2333 #else
2334         return len;
2335 #endif
2336 }
2337
2338 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2339 {
2340         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2341                 BUG();
2342 #if (PAGE_SIZE >= 65536)
2343         if (len < 65536)
2344                 return cpu_to_le16(len);
2345         if (len == blocksize) {
2346                 if (blocksize == 65536)
2347                         return cpu_to_le16(EXT4_MAX_REC_LEN);
2348                 else
2349                         return cpu_to_le16(0);
2350         }
2351         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2352 #else
2353         return cpu_to_le16(len);
2354 #endif
2355 }
2356
2357 /*
2358  * Hash Tree Directory indexing
2359  * (c) Daniel Phillips, 2001
2360  */
2361
2362 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2363                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2364 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2365                     !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2366 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2367
2368 /* Legal values for the dx_root hash_version field: */
2369
2370 #define DX_HASH_LEGACY                  0
2371 #define DX_HASH_HALF_MD4                1
2372 #define DX_HASH_TEA                     2
2373 #define DX_HASH_LEGACY_UNSIGNED         3
2374 #define DX_HASH_HALF_MD4_UNSIGNED       4
2375 #define DX_HASH_TEA_UNSIGNED            5
2376 #define DX_HASH_SIPHASH                 6
2377
2378 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2379                               const void *address, unsigned int length)
2380 {
2381         struct {
2382                 struct shash_desc shash;
2383                 char ctx[4];
2384         } desc;
2385
2386         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2387
2388         desc.shash.tfm = sbi->s_chksum_driver;
2389         *(u32 *)desc.ctx = crc;
2390
2391         BUG_ON(crypto_shash_update(&desc.shash, address, length));
2392
2393         return *(u32 *)desc.ctx;
2394 }
2395
2396 #ifdef __KERNEL__
2397
2398 /* hash info structure used by the directory hash */
2399 struct dx_hash_info
2400 {
2401         u32             hash;
2402         u32             minor_hash;
2403         int             hash_version;
2404         u32             *seed;
2405 };
2406
2407
2408 /* 32 and 64 bit signed EOF for dx directories */
2409 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2410 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2411
2412
2413 /*
2414  * Control parameters used by ext4_htree_next_block
2415  */
2416 #define HASH_NB_ALWAYS          1
2417
2418 struct ext4_filename {
2419         const struct qstr *usr_fname;
2420         struct fscrypt_str disk_name;
2421         struct dx_hash_info hinfo;
2422 #ifdef CONFIG_FS_ENCRYPTION
2423         struct fscrypt_str crypto_buf;
2424 #endif
2425 #ifdef CONFIG_UNICODE
2426         struct fscrypt_str cf_name;
2427 #endif
2428 };
2429
2430 #define fname_name(p) ((p)->disk_name.name)
2431 #define fname_usr_name(p) ((p)->usr_fname->name)
2432 #define fname_len(p)  ((p)->disk_name.len)
2433
2434 /*
2435  * Describe an inode's exact location on disk and in memory
2436  */
2437 struct ext4_iloc
2438 {
2439         struct buffer_head *bh;
2440         unsigned long offset;
2441         ext4_group_t block_group;
2442 };
2443
2444 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2445 {
2446         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2447 }
2448
2449 static inline bool ext4_is_quota_file(struct inode *inode)
2450 {
2451         return IS_NOQUOTA(inode) &&
2452                !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2453 }
2454
2455 /*
2456  * This structure is stuffed into the struct file's private_data field
2457  * for directories.  It is where we put information so that we can do
2458  * readdir operations in hash tree order.
2459  */
2460 struct dir_private_info {
2461         struct rb_root  root;
2462         struct rb_node  *curr_node;
2463         struct fname    *extra_fname;
2464         loff_t          last_pos;
2465         __u32           curr_hash;
2466         __u32           curr_minor_hash;
2467         __u32           next_hash;
2468 };
2469
2470 /* calculate the first block number of the group */
2471 static inline ext4_fsblk_t
2472 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2473 {
2474         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2475                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2476 }
2477
2478 /*
2479  * Special error return code only used by dx_probe() and its callers.
2480  */
2481 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
2482
2483 /* htree levels for ext4 */
2484 #define EXT4_HTREE_LEVEL_COMPAT 2
2485 #define EXT4_HTREE_LEVEL        3
2486
2487 static inline int ext4_dir_htree_level(struct super_block *sb)
2488 {
2489         return ext4_has_feature_largedir(sb) ?
2490                 EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2491 }
2492
2493 /*
2494  * Timeout and state flag for lazy initialization inode thread.
2495  */
2496 #define EXT4_DEF_LI_WAIT_MULT                   10
2497 #define EXT4_DEF_LI_MAX_START_DELAY             5
2498 #define EXT4_LAZYINIT_QUIT                      0x0001
2499 #define EXT4_LAZYINIT_RUNNING                   0x0002
2500
2501 /*
2502  * Lazy inode table initialization info
2503  */
2504 struct ext4_lazy_init {
2505         unsigned long           li_state;
2506         struct list_head        li_request_list;
2507         struct mutex            li_list_mtx;
2508 };
2509
2510 enum ext4_li_mode {
2511         EXT4_LI_MODE_PREFETCH_BBITMAP,
2512         EXT4_LI_MODE_ITABLE,
2513 };
2514
2515 struct ext4_li_request {
2516         struct super_block      *lr_super;
2517         enum ext4_li_mode       lr_mode;
2518         ext4_group_t            lr_first_not_zeroed;
2519         ext4_group_t            lr_next_group;
2520         struct list_head        lr_request;
2521         unsigned long           lr_next_sched;
2522         unsigned long           lr_timeout;
2523 };
2524
2525 struct ext4_features {
2526         struct kobject f_kobj;
2527         struct completion f_kobj_unregister;
2528 };
2529
2530 /*
2531  * This structure will be used for multiple mount protection. It will be
2532  * written into the block number saved in the s_mmp_block field in the
2533  * superblock. Programs that check MMP should assume that if
2534  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2535  * to use the filesystem, regardless of how old the timestamp is.
2536  */
2537 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2538 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2539 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2540 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2541
2542 struct mmp_struct {
2543         __le32  mmp_magic;              /* Magic number for MMP */
2544         __le32  mmp_seq;                /* Sequence no. updated periodically */
2545
2546         /*
2547          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2548          * purposes and do not affect the correctness of the algorithm
2549          */
2550         __le64  mmp_time;               /* Time last updated */
2551         char    mmp_nodename[64];       /* Node which last updated MMP block */
2552         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
2553
2554         /*
2555          * mmp_check_interval is used to verify if the MMP block has been
2556          * updated on the block device. The value is updated based on the
2557          * maximum time to write the MMP block during an update cycle.
2558          */
2559         __le16  mmp_check_interval;
2560
2561         __le16  mmp_pad1;
2562         __le32  mmp_pad2[226];
2563         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
2564 };
2565
2566 /* arguments passed to the mmp thread */
2567 struct mmpd_data {
2568         struct buffer_head *bh; /* bh from initial read_mmp_block() */
2569         struct super_block *sb;  /* super block of the fs */
2570 };
2571
2572 /*
2573  * Check interval multiplier
2574  * The MMP block is written every update interval and initially checked every
2575  * update interval x the multiplier (the value is then adapted based on the
2576  * write latency). The reason is that writes can be delayed under load and we
2577  * don't want readers to incorrectly assume that the filesystem is no longer
2578  * in use.
2579  */
2580 #define EXT4_MMP_CHECK_MULT             2UL
2581
2582 /*
2583  * Minimum interval for MMP checking in seconds.
2584  */
2585 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
2586
2587 /*
2588  * Maximum interval for MMP checking in seconds.
2589  */
2590 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
2591
2592 /*
2593  * Function prototypes
2594  */
2595
2596 /*
2597  * Ok, these declarations are also in <linux/kernel.h> but none of the
2598  * ext4 source programs needs to include it so they are duplicated here.
2599  */
2600 # define NORET_TYPE     /**/
2601 # define ATTRIB_NORET   __attribute__((noreturn))
2602 # define NORET_AND      noreturn,
2603
2604 /* bitmap.c */
2605 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2606 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2607                                 struct ext4_group_desc *gdp,
2608                                 struct buffer_head *bh, int sz);
2609 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2610                                   struct ext4_group_desc *gdp,
2611                                   struct buffer_head *bh, int sz);
2612 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2613                                 struct ext4_group_desc *gdp,
2614                                 struct buffer_head *bh);
2615 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2616                                   struct ext4_group_desc *gdp,
2617                                   struct buffer_head *bh);
2618
2619 /* balloc.c */
2620 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2621                                          ext4_fsblk_t blocknr,
2622                                          ext4_group_t *blockgrpp,
2623                                          ext4_grpblk_t *offsetp);
2624 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2625                                           ext4_fsblk_t block);
2626
2627 extern unsigned int ext4_block_group(struct super_block *sb,
2628                         ext4_fsblk_t blocknr);
2629 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2630                         ext4_fsblk_t blocknr);
2631 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2632 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2633                         ext4_group_t group);
2634 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2635                                          ext4_fsblk_t goal,
2636                                          unsigned int flags,
2637                                          unsigned long *count,
2638                                          int *errp);
2639 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2640                                     s64 nclusters, unsigned int flags);
2641 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2642 extern void ext4_check_blocks_bitmap(struct super_block *);
2643 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2644                                                     ext4_group_t block_group,
2645                                                     struct buffer_head ** bh);
2646 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2647
2648 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2649                                                 ext4_group_t block_group,
2650                                                 bool ignore_locked);
2651 extern int ext4_wait_block_bitmap(struct super_block *sb,
2652                                   ext4_group_t block_group,
2653                                   struct buffer_head *bh);
2654 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2655                                                   ext4_group_t block_group);
2656 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2657                                               ext4_group_t block_group,
2658                                               struct ext4_group_desc *gdp);
2659 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2660
2661 #ifdef CONFIG_UNICODE
2662 extern int ext4_fname_setup_ci_filename(struct inode *dir,
2663                                          const struct qstr *iname,
2664                                          struct ext4_filename *fname);
2665 #endif
2666
2667 #ifdef CONFIG_FS_ENCRYPTION
2668 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2669                                                 const struct fscrypt_name *src)
2670 {
2671         memset(dst, 0, sizeof(*dst));
2672
2673         dst->usr_fname = src->usr_fname;
2674         dst->disk_name = src->disk_name;
2675         dst->hinfo.hash = src->hash;
2676         dst->hinfo.minor_hash = src->minor_hash;
2677         dst->crypto_buf = src->crypto_buf;
2678 }
2679
2680 static inline int ext4_fname_setup_filename(struct inode *dir,
2681                                             const struct qstr *iname,
2682                                             int lookup,
2683                                             struct ext4_filename *fname)
2684 {
2685         struct fscrypt_name name;
2686         int err;
2687
2688         err = fscrypt_setup_filename(dir, iname, lookup, &name);
2689         if (err)
2690                 return err;
2691
2692         ext4_fname_from_fscrypt_name(fname, &name);
2693
2694 #ifdef CONFIG_UNICODE
2695         err = ext4_fname_setup_ci_filename(dir, iname, fname);
2696 #endif
2697         return err;
2698 }
2699
2700 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2701                                             struct dentry *dentry,
2702                                             struct ext4_filename *fname)
2703 {
2704         struct fscrypt_name name;
2705         int err;
2706
2707         err = fscrypt_prepare_lookup(dir, dentry, &name);
2708         if (err)
2709                 return err;
2710
2711         ext4_fname_from_fscrypt_name(fname, &name);
2712
2713 #ifdef CONFIG_UNICODE
2714         err = ext4_fname_setup_ci_filename(dir, &dentry->d_name, fname);
2715 #endif
2716         return err;
2717 }
2718
2719 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2720 {
2721         struct fscrypt_name name;
2722
2723         name.crypto_buf = fname->crypto_buf;
2724         fscrypt_free_filename(&name);
2725
2726         fname->crypto_buf.name = NULL;
2727         fname->usr_fname = NULL;
2728         fname->disk_name.name = NULL;
2729
2730 #ifdef CONFIG_UNICODE
2731         kfree(fname->cf_name.name);
2732         fname->cf_name.name = NULL;
2733 #endif
2734 }
2735 #else /* !CONFIG_FS_ENCRYPTION */
2736 static inline int ext4_fname_setup_filename(struct inode *dir,
2737                                             const struct qstr *iname,
2738                                             int lookup,
2739                                             struct ext4_filename *fname)
2740 {
2741         int err = 0;
2742         fname->usr_fname = iname;
2743         fname->disk_name.name = (unsigned char *) iname->name;
2744         fname->disk_name.len = iname->len;
2745
2746 #ifdef CONFIG_UNICODE
2747         err = ext4_fname_setup_ci_filename(dir, iname, fname);
2748 #endif
2749
2750         return err;
2751 }
2752
2753 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2754                                             struct dentry *dentry,
2755                                             struct ext4_filename *fname)
2756 {
2757         return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2758 }
2759
2760 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2761 {
2762 #ifdef CONFIG_UNICODE
2763         kfree(fname->cf_name.name);
2764         fname->cf_name.name = NULL;
2765 #endif
2766 }
2767 #endif /* !CONFIG_FS_ENCRYPTION */
2768
2769 /* dir.c */
2770 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2771                                   struct file *,
2772                                   struct ext4_dir_entry_2 *,
2773                                   struct buffer_head *, char *, int,
2774                                   unsigned int);
2775 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
2776         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2777                                 (de), (bh), (buf), (size), (offset)))
2778 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2779                                 __u32 minor_hash,
2780                                 struct ext4_dir_entry_2 *dirent,
2781                                 struct fscrypt_str *ent_name);
2782 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2783 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2784                              struct buffer_head *bh,
2785                              void *buf, int buf_size,
2786                              struct ext4_filename *fname,
2787                              struct ext4_dir_entry_2 **dest_de);
2788 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
2789                         struct ext4_dir_entry_2 *de,
2790                         int buf_size,
2791                         struct ext4_filename *fname);
2792 static inline void ext4_update_dx_flag(struct inode *inode)
2793 {
2794         if (!ext4_has_feature_dir_index(inode->i_sb) &&
2795             ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
2796                 /* ext4_iget() should have caught this... */
2797                 WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2798                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2799         }
2800 }
2801 static const unsigned char ext4_filetype_table[] = {
2802         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2803 };
2804
2805 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2806 {
2807         if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2808                 return DT_UNKNOWN;
2809
2810         return ext4_filetype_table[filetype];
2811 }
2812 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2813                              void *buf, int buf_size);
2814
2815 /* fsync.c */
2816 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2817
2818 /* hash.c */
2819 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2820                           struct dx_hash_info *hinfo);
2821
2822 /* ialloc.c */
2823 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2824 extern struct inode *__ext4_new_inode(struct user_namespace *, handle_t *,
2825                                       struct inode *, umode_t,
2826                                       const struct qstr *qstr, __u32 goal,
2827                                       uid_t *owner, __u32 i_flags,
2828                                       int handle_type, unsigned int line_no,
2829                                       int nblocks);
2830
2831 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
2832         __ext4_new_inode(&init_user_ns, (handle), (dir), (mode), (qstr),       \
2833                          (goal), (owner), i_flags, 0, 0, 0)
2834 #define ext4_new_inode_start_handle(mnt_userns, dir, mode, qstr, goal, owner, \
2835                                     type, nblocks)                  \
2836         __ext4_new_inode((mnt_userns), NULL, (dir), (mode), (qstr), (goal), (owner), \
2837                          0, (type), __LINE__, (nblocks))
2838
2839
2840 extern void ext4_free_inode(handle_t *, struct inode *);
2841 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2842 extern unsigned long ext4_count_free_inodes(struct super_block *);
2843 extern unsigned long ext4_count_dirs(struct super_block *);
2844 extern void ext4_check_inodes_bitmap(struct super_block *);
2845 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2846 extern int ext4_init_inode_table(struct super_block *sb,
2847                                  ext4_group_t group, int barrier);
2848 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2849
2850 /* fast_commit.c */
2851 int ext4_fc_info_show(struct seq_file *seq, void *v);
2852 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2853 void ext4_fc_init_inode(struct inode *inode);
2854 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
2855                          ext4_lblk_t end);
2856 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
2857         struct dentry *dentry);
2858 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
2859         struct dentry *dentry);
2860 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
2861 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
2862 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
2863                             struct dentry *dentry);
2864 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
2865 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
2866 void ext4_fc_mark_ineligible(struct super_block *sb, int reason);
2867 void ext4_fc_start_ineligible(struct super_block *sb, int reason);
2868 void ext4_fc_stop_ineligible(struct super_block *sb);
2869 void ext4_fc_start_update(struct inode *inode);
2870 void ext4_fc_stop_update(struct inode *inode);
2871 void ext4_fc_del(struct inode *inode);
2872 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2873 void ext4_fc_replay_cleanup(struct super_block *sb);
2874 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2875 int __init ext4_fc_init_dentry_cache(void);
2876
2877 /* mballoc.c */
2878 extern const struct seq_operations ext4_mb_seq_groups_ops;
2879 extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
2880 extern long ext4_mb_stats;
2881 extern long ext4_mb_max_to_scan;
2882 extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset);
2883 extern int ext4_mb_init(struct super_block *);
2884 extern int ext4_mb_release(struct super_block *);
2885 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2886                                 struct ext4_allocation_request *, int *);
2887 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2888 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2889 extern int __init ext4_init_mballoc(void);
2890 extern void ext4_exit_mballoc(void);
2891 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2892                                      ext4_group_t group,
2893                                      unsigned int nr, int *cnt);
2894 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2895                                   unsigned int nr);
2896
2897 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2898                              struct buffer_head *bh, ext4_fsblk_t block,
2899                              unsigned long count, int flags);
2900 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2901                                    ext4_group_t ngroups);
2902 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2903                 ext4_group_t i, struct ext4_group_desc *desc);
2904 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2905                                 ext4_fsblk_t block, unsigned long count);
2906 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2907 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2908 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2909                        int len, int state);
2910
2911 /* inode.c */
2912 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2913                          struct ext4_inode_info *ei);
2914 int ext4_inode_is_fast_symlink(struct inode *inode);
2915 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2916 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2917 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2918                      bool wait, struct buffer_head **bhs);
2919 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2920                              struct buffer_head *bh_result, int create);
2921 int ext4_get_block(struct inode *inode, sector_t iblock,
2922                    struct buffer_head *bh_result, int create);
2923 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2924                            struct buffer_head *bh, int create);
2925 int ext4_walk_page_buffers(handle_t *handle,
2926                            struct buffer_head *head,
2927                            unsigned from,
2928                            unsigned to,
2929                            int *partial,
2930                            int (*fn)(handle_t *handle,
2931                                      struct buffer_head *bh));
2932 int do_journal_get_write_access(handle_t *handle,
2933                                 struct buffer_head *bh);
2934 #define FALL_BACK_TO_NONDELALLOC 1
2935 #define CONVERT_INLINE_DATA      2
2936
2937 typedef enum {
2938         EXT4_IGET_NORMAL =      0,
2939         EXT4_IGET_SPECIAL =     0x0001, /* OK to iget a system inode */
2940         EXT4_IGET_HANDLE =      0x0002  /* Inode # is from a handle */
2941 } ext4_iget_flags;
2942
2943 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2944                                  ext4_iget_flags flags, const char *function,
2945                                  unsigned int line);
2946
2947 #define ext4_iget(sb, ino, flags) \
2948         __ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2949
2950 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2951 extern int  ext4_setattr(struct user_namespace *, struct dentry *,
2952                          struct iattr *);
2953 extern int  ext4_getattr(struct user_namespace *, const struct path *,
2954                          struct kstat *, u32, unsigned int);
2955 extern void ext4_evict_inode(struct inode *);
2956 extern void ext4_clear_inode(struct inode *);
2957 extern int  ext4_file_getattr(struct user_namespace *, const struct path *,
2958                               struct kstat *, u32, unsigned int);
2959 extern int  ext4_sync_inode(handle_t *, struct inode *);
2960 extern void ext4_dirty_inode(struct inode *, int);
2961 extern int ext4_change_inode_journal_flag(struct inode *, int);
2962 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2963 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2964                           struct ext4_iloc *iloc);
2965 extern int ext4_inode_attach_jinode(struct inode *inode);
2966 extern int ext4_can_truncate(struct inode *inode);
2967 extern int ext4_truncate(struct inode *);
2968 extern int ext4_break_layouts(struct inode *);
2969 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2970 extern void ext4_set_inode_flags(struct inode *, bool init);
2971 extern int ext4_alloc_da_blocks(struct inode *inode);
2972 extern void ext4_set_aops(struct inode *inode);
2973 extern int ext4_writepage_trans_blocks(struct inode *);
2974 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2975 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2976                              loff_t lstart, loff_t lend);
2977 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2978 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2979 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2980 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2981 extern void ext4_da_release_space(struct inode *inode, int to_free);
2982 extern void ext4_da_update_reserve_space(struct inode *inode,
2983                                         int used, int quota_claim);
2984 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2985                               ext4_fsblk_t pblk, ext4_lblk_t len);
2986
2987 /* indirect.c */
2988 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2989                                 struct ext4_map_blocks *map, int flags);
2990 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2991 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2992 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2993                                  ext4_lblk_t start, ext4_lblk_t end);
2994
2995 /* ioctl.c */
2996 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2997 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2998 int ext4_fileattr_set(struct user_namespace *mnt_userns,
2999                       struct dentry *dentry, struct fileattr *fa);
3000 int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa);
3001 extern void ext4_reset_inode_seed(struct inode *inode);
3002
3003 /* migrate.c */
3004 extern int ext4_ext_migrate(struct inode *);
3005 extern int ext4_ind_migrate(struct inode *inode);
3006
3007 /* namei.c */
3008 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
3009                              struct inode *inode);
3010 extern int ext4_dirblock_csum_verify(struct inode *inode,
3011                                      struct buffer_head *bh);
3012 extern int ext4_orphan_add(handle_t *, struct inode *);
3013 extern int ext4_orphan_del(handle_t *, struct inode *);
3014 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
3015                                 __u32 start_minor_hash, __u32 *next_hash);
3016 extern int ext4_search_dir(struct buffer_head *bh,
3017                            char *search_buf,
3018                            int buf_size,
3019                            struct inode *dir,
3020                            struct ext4_filename *fname,
3021                            unsigned int offset,
3022                            struct ext4_dir_entry_2 **res_dir);
3023 extern int ext4_generic_delete_entry(struct inode *dir,
3024                                      struct ext4_dir_entry_2 *de_del,
3025                                      struct buffer_head *bh,
3026                                      void *entry_buf,
3027                                      int buf_size,
3028                                      int csum_size);
3029 extern bool ext4_empty_dir(struct inode *inode);
3030
3031 /* resize.c */
3032 extern void ext4_kvfree_array_rcu(void *to_free);
3033 extern int ext4_group_add(struct super_block *sb,
3034                                 struct ext4_new_group_data *input);
3035 extern int ext4_group_extend(struct super_block *sb,
3036                                 struct ext4_super_block *es,
3037                                 ext4_fsblk_t n_blocks_count);
3038 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
3039
3040 /* super.c */
3041 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
3042                                          sector_t block, int op_flags);
3043 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
3044                                                    sector_t block);
3045 extern void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
3046                                 bh_end_io_t *end_io);
3047 extern int ext4_read_bh(struct buffer_head *bh, int op_flags,
3048                         bh_end_io_t *end_io);
3049 extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
3050 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
3051 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
3052 extern int ext4_calculate_overhead(struct super_block *sb);
3053 extern void ext4_superblock_csum_set(struct super_block *sb);
3054 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
3055                                     ext4_group_t ngroup);
3056 extern const char *ext4_decode_error(struct super_block *sb, int errno,
3057                                      char nbuf[16]);
3058 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
3059                                              ext4_group_t block_group,
3060                                              unsigned int flags);
3061
3062 extern __printf(7, 8)
3063 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
3064                   int, __u64, const char *, ...);
3065 extern __printf(6, 7)
3066 void __ext4_error_inode(struct inode *, const char *, unsigned int,
3067                         ext4_fsblk_t, int, const char *, ...);
3068 extern __printf(5, 6)
3069 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
3070                      const char *, ...);
3071 extern void __ext4_std_error(struct super_block *, const char *,
3072                              unsigned int, int);
3073 extern __printf(4, 5)
3074 void __ext4_warning(struct super_block *, const char *, unsigned int,
3075                     const char *, ...);
3076 extern __printf(4, 5)
3077 void __ext4_warning_inode(const struct inode *inode, const char *function,
3078                           unsigned int line, const char *fmt, ...);
3079 extern __printf(3, 4)
3080 void __ext4_msg(struct super_block *, const char *, const char *, ...);
3081 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
3082                            const char *, unsigned int, const char *);
3083 extern __printf(7, 8)
3084 void __ext4_grp_locked_error(const char *, unsigned int,
3085                              struct super_block *, ext4_group_t,
3086                              unsigned long, ext4_fsblk_t,
3087                              const char *, ...);
3088
3089 #define EXT4_ERROR_INODE(inode, fmt, a...) \
3090         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3091
3092 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)                     \
3093         __ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3094
3095 #define ext4_error_inode_block(inode, block, err, fmt, a...)            \
3096         __ext4_error_inode((inode), __func__, __LINE__, (block), (err), \
3097                            (fmt), ## a)
3098
3099 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
3100         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3101
3102 #define ext4_abort(sb, err, fmt, a...)                                  \
3103         __ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3104
3105 #ifdef CONFIG_PRINTK
3106
3107 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
3108         __ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3109 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
3110         __ext4_error_inode((inode), (func), (line), (block),            \
3111                            (err), (fmt), ##__VA_ARGS__)
3112 #define ext4_error_file(file, func, line, block, fmt, ...)              \
3113         __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3114 #define ext4_error(sb, fmt, ...)                                        \
3115         __ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),      \
3116                 ##__VA_ARGS__)
3117 #define ext4_error_err(sb, err, fmt, ...)                               \
3118         __ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),  \
3119                 ##__VA_ARGS__)
3120 #define ext4_warning(sb, fmt, ...)                                      \
3121         __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3122 #define ext4_warning_inode(inode, fmt, ...)                             \
3123         __ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3124 #define ext4_msg(sb, level, fmt, ...)                           \
3125         __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3126 #define dump_mmp_msg(sb, mmp, msg)                                      \
3127         __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3128 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
3129         __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3130                                 fmt, ##__VA_ARGS__)
3131
3132 #else
3133
3134 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
3135 do {                                                                    \
3136         no_printk(fmt, ##__VA_ARGS__);                                  \
3137         __ext4_error_inode(inode, "", 0, block, 0, " ");                \
3138 } while (0)
3139 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
3140 do {                                                                    \
3141         no_printk(fmt, ##__VA_ARGS__);                                  \
3142         __ext4_error_inode(inode, "", 0, block, err, " ");              \
3143 } while (0)
3144 #define ext4_error_file(file, func, line, block, fmt, ...)              \
3145 do {                                                                    \
3146         no_printk(fmt, ##__VA_ARGS__);                                  \
3147         __ext4_error_file(file, "", 0, block, " ");                     \
3148 } while (0)
3149 #define ext4_error(sb, fmt, ...)                                        \
3150 do {                                                                    \
3151         no_printk(fmt, ##__VA_ARGS__);                                  \
3152         __ext4_error(sb, "", 0, false, 0, 0, " ");                      \
3153 } while (0)
3154 #define ext4_error_err(sb, err, fmt, ...)                               \
3155 do {                                                                    \
3156         no_printk(fmt, ##__VA_ARGS__);                                  \
3157         __ext4_error(sb, "", 0, false, err, 0, " ");                    \
3158 } while (0)
3159 #define ext4_warning(sb, fmt, ...)                                      \
3160 do {                                                                    \
3161         no_printk(fmt, ##__VA_ARGS__);                                  \
3162         __ext4_warning(sb, "", 0, " ");                                 \
3163 } while (0)
3164 #define ext4_warning_inode(inode, fmt, ...)                             \
3165 do {                                                                    \
3166         no_printk(fmt, ##__VA_ARGS__);                                  \
3167         __ext4_warning_inode(inode, "", 0, " ");                        \
3168 } while (0)
3169 #define ext4_msg(sb, level, fmt, ...)                                   \
3170 do {                                                                    \
3171         no_printk(fmt, ##__VA_ARGS__);                                  \
3172         __ext4_msg(sb, "", " ");                                        \
3173 } while (0)
3174 #define dump_mmp_msg(sb, mmp, msg)                                      \
3175         __dump_mmp_msg(sb, mmp, "", 0, "")
3176 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
3177 do {                                                                    \
3178         no_printk(fmt, ##__VA_ARGS__);                          \
3179         __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");       \
3180 } while (0)
3181
3182 #endif
3183
3184 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3185                                       struct ext4_group_desc *bg);
3186 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3187                                       struct ext4_group_desc *bg);
3188 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3189                                      struct ext4_group_desc *bg);
3190 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3191                                       struct ext4_group_desc *bg);
3192 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3193                                  struct ext4_group_desc *bg);
3194 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3195                                 struct ext4_group_desc *bg);
3196 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3197                                    struct ext4_group_desc *bg);
3198 extern void ext4_block_bitmap_set(struct super_block *sb,
3199                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
3200 extern void ext4_inode_bitmap_set(struct super_block *sb,
3201                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
3202 extern void ext4_inode_table_set(struct super_block *sb,
3203                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3204 extern void ext4_free_group_clusters_set(struct super_block *sb,
3205                                          struct ext4_group_desc *bg,
3206                                          __u32 count);
3207 extern void ext4_free_inodes_set(struct super_block *sb,
3208                                 struct ext4_group_desc *bg, __u32 count);
3209 extern void ext4_used_dirs_set(struct super_block *sb,
3210                                 struct ext4_group_desc *bg, __u32 count);
3211 extern void ext4_itable_unused_set(struct super_block *sb,
3212                                    struct ext4_group_desc *bg, __u32 count);
3213 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3214                                        struct ext4_group_desc *gdp);
3215 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3216                                      struct ext4_group_desc *gdp);
3217 extern int ext4_register_li_request(struct super_block *sb,
3218                                     ext4_group_t first_not_zeroed);
3219
3220 static inline int ext4_has_metadata_csum(struct super_block *sb)
3221 {
3222         WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3223                      !EXT4_SB(sb)->s_chksum_driver);
3224
3225         return ext4_has_feature_metadata_csum(sb) &&
3226                (EXT4_SB(sb)->s_chksum_driver != NULL);
3227 }
3228
3229 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3230 {
3231         return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3232 }
3233
3234 #define ext4_read_incompat_64bit_val(es, name) \
3235         (((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3236                 ? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3237                 le32_to_cpu(es->name##_lo))
3238
3239 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3240 {
3241         return ext4_read_incompat_64bit_val(es, s_blocks_count);
3242 }
3243
3244 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3245 {
3246         return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3247 }
3248
3249 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3250 {
3251         return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3252 }
3253
3254 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3255                                          ext4_fsblk_t blk)
3256 {
3257         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3258         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3259 }
3260
3261 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3262                                               ext4_fsblk_t blk)
3263 {
3264         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3265         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3266 }
3267
3268 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3269                                            ext4_fsblk_t blk)
3270 {
3271         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3272         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3273 }
3274
3275 static inline loff_t ext4_isize(struct super_block *sb,
3276                                 struct ext4_inode *raw_inode)
3277 {
3278         if (ext4_has_feature_largedir(sb) ||
3279             S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3280                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3281                         le32_to_cpu(raw_inode->i_size_lo);
3282
3283         return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3284 }
3285
3286 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3287 {
3288         raw_inode->i_size_lo = cpu_to_le32(i_size);
3289         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3290 }
3291
3292 static inline
3293 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3294                                             ext4_group_t group)
3295 {
3296          struct ext4_group_info **grp_info;
3297          long indexv, indexh;
3298          BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3299          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3300          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3301          grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3302          return grp_info[indexh];
3303 }
3304
3305 /*
3306  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3307  * the locking protocol documented in the comments of ext4_group_add()
3308  * in resize.c
3309  */
3310 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3311 {
3312         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
3313
3314         smp_rmb();
3315         return ngroups;
3316 }
3317
3318 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3319                                              ext4_group_t block_group)
3320 {
3321         return block_group >> sbi->s_log_groups_per_flex;
3322 }
3323
3324 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3325 {
3326         return 1 << sbi->s_log_groups_per_flex;
3327 }
3328
3329 #define ext4_std_error(sb, errno)                               \
3330 do {                                                            \
3331         if ((errno))                                            \
3332                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
3333 } while (0)
3334
3335 #ifdef CONFIG_SMP
3336 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3337  * counters. So we need to make sure we have free clusters more
3338  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3339  */
3340 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3341 #else
3342 #define EXT4_FREECLUSTERS_WATERMARK 0
3343 #endif
3344
3345 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
3346 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3347 {
3348         WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3349                      !inode_is_locked(inode));
3350         down_write(&EXT4_I(inode)->i_data_sem);
3351         if (newsize > EXT4_I(inode)->i_disksize)
3352                 WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3353         up_write(&EXT4_I(inode)->i_data_sem);
3354 }
3355
3356 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
3357 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3358 {
3359         int changed = 0;
3360
3361         if (newsize > inode->i_size) {
3362                 i_size_write(inode, newsize);
3363                 changed = 1;
3364         }
3365         if (newsize > EXT4_I(inode)->i_disksize) {
3366                 ext4_update_i_disksize(inode, newsize);
3367                 changed |= 2;
3368         }
3369         return changed;
3370 }
3371
3372 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3373                                       loff_t len);
3374
3375 struct ext4_group_info {
3376         unsigned long   bb_state;
3377 #ifdef AGGRESSIVE_CHECK
3378         unsigned long   bb_check_counter;
3379 #endif
3380         struct rb_root  bb_free_root;
3381         ext4_grpblk_t   bb_first_free;  /* first free block */
3382         ext4_grpblk_t   bb_free;        /* total free blocks */
3383         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
3384         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
3385         ext4_group_t    bb_group;       /* Group number */
3386         struct          list_head bb_prealloc_list;
3387 #ifdef DOUBLE_CHECK
3388         void            *bb_bitmap;
3389 #endif
3390         struct rw_semaphore alloc_sem;
3391         struct rb_node  bb_avg_fragment_size_rb;
3392         struct list_head bb_largest_free_order_node;
3393         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
3394                                          * regions, index is order.
3395                                          * bb_counters[3] = 5 means
3396                                          * 5 free 8-block regions. */
3397 };
3398
3399 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
3400 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
3401 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT     2
3402 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT     3
3403 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT         \
3404         (1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3405 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT         \
3406         (1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3407 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT        4
3408
3409 #define EXT4_MB_GRP_NEED_INIT(grp)      \
3410         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3411 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)        \
3412         (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3413 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)        \
3414         (test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3415
3416 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
3417         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3418 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
3419         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3420 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
3421         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3422 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)      \
3423         (test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3424
3425 #define EXT4_MAX_CONTENTION             8
3426 #define EXT4_CONTENTION_THRESHOLD       2
3427
3428 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3429                                               ext4_group_t group)
3430 {
3431         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3432 }
3433
3434 /*
3435  * Returns true if the filesystem is busy enough that attempts to
3436  * access the block group locks has run into contention.
3437  */
3438 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3439 {
3440         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3441 }
3442
3443 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3444 {
3445         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3446         if (spin_trylock(lock))
3447                 /*
3448                  * We're able to grab the lock right away, so drop the
3449                  * lock contention counter.
3450                  */
3451                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3452         else {
3453                 /*
3454                  * The lock is busy, so bump the contention counter,
3455                  * and then wait on the spin lock.
3456                  */
3457                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3458                                   EXT4_MAX_CONTENTION);
3459                 spin_lock(lock);
3460         }
3461 }
3462
3463 static inline void ext4_unlock_group(struct super_block *sb,
3464                                         ext4_group_t group)
3465 {
3466         spin_unlock(ext4_group_lock_ptr(sb, group));
3467 }
3468
3469 #ifdef CONFIG_QUOTA
3470 static inline bool ext4_quota_capable(struct super_block *sb)
3471 {
3472         return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
3473 }
3474
3475 static inline bool ext4_is_quota_journalled(struct super_block *sb)
3476 {
3477         struct ext4_sb_info *sbi = EXT4_SB(sb);
3478
3479         return (ext4_has_feature_quota(sb) ||
3480                 sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
3481 }
3482 #endif
3483
3484 /*
3485  * Block validity checking
3486  */
3487 #define ext4_check_indirect_blockref(inode, bh)                         \
3488         ext4_check_blockref(__func__, __LINE__, inode,                  \
3489                             (__le32 *)(bh)->b_data,                     \
3490                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3491
3492 #define ext4_ind_check_inode(inode)                                     \
3493         ext4_check_blockref(__func__, __LINE__, inode,                  \
3494                             EXT4_I(inode)->i_data,                      \
3495                             EXT4_NDIR_BLOCKS)
3496
3497 /*
3498  * Inodes and files operations
3499  */
3500
3501 /* dir.c */
3502 extern const struct file_operations ext4_dir_operations;
3503
3504 /* file.c */
3505 extern const struct inode_operations ext4_file_inode_operations;
3506 extern const struct file_operations ext4_file_operations;
3507 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3508
3509 /* inline.c */
3510 extern int ext4_get_max_inline_size(struct inode *inode);
3511 extern int ext4_find_inline_data_nolock(struct inode *inode);
3512 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3513                                  unsigned int len);
3514 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3515
3516 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3517 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3518                                          struct inode *inode,
3519                                          loff_t pos, unsigned len,
3520                                          unsigned flags,
3521                                          struct page **pagep);
3522 extern int ext4_write_inline_data_end(struct inode *inode,
3523                                       loff_t pos, unsigned len,
3524                                       unsigned copied,
3525                                       struct page *page);
3526 extern struct buffer_head *
3527 ext4_journalled_write_inline_data(struct inode *inode,
3528                                   unsigned len,
3529                                   struct page *page);
3530 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3531                                            struct inode *inode,
3532                                            loff_t pos, unsigned len,
3533                                            unsigned flags,
3534                                            struct page **pagep,
3535                                            void **fsdata);
3536 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3537                                          unsigned len, unsigned copied,
3538                                          struct page *page);
3539 extern int ext4_try_add_inline_entry(handle_t *handle,
3540                                      struct ext4_filename *fname,
3541                                      struct inode *dir, struct inode *inode);
3542 extern int ext4_try_create_inline_dir(handle_t *handle,
3543                                       struct inode *parent,
3544                                       struct inode *inode);
3545 extern int ext4_read_inline_dir(struct file *filp,
3546                                 struct dir_context *ctx,
3547                                 int *has_inline_data);
3548 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3549                                   struct inode *dir, ext4_lblk_t block,
3550                                   struct dx_hash_info *hinfo,
3551                                   __u32 start_hash, __u32 start_minor_hash,
3552                                   int *has_inline_data);
3553 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3554                                         struct ext4_filename *fname,
3555                                         struct ext4_dir_entry_2 **res_dir,
3556                                         int *has_inline_data);
3557 extern int ext4_delete_inline_entry(handle_t *handle,
3558                                     struct inode *dir,
3559                                     struct ext4_dir_entry_2 *de_del,
3560                                     struct buffer_head *bh,
3561                                     int *has_inline_data);
3562 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3563 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3564                                         struct ext4_dir_entry_2 **parent_de,
3565                                         int *retval);
3566 extern int ext4_inline_data_fiemap(struct inode *inode,
3567                                    struct fiemap_extent_info *fieinfo,
3568                                    int *has_inline, __u64 start, __u64 len);
3569
3570 struct iomap;
3571 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3572
3573 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3574
3575 extern int ext4_convert_inline_data(struct inode *inode);
3576
3577 static inline int ext4_has_inline_data(struct inode *inode)
3578 {
3579         return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3580                EXT4_I(inode)->i_inline_off;
3581 }
3582
3583 /* namei.c */
3584 extern const struct inode_operations ext4_dir_inode_operations;
3585 extern const struct inode_operations ext4_special_inode_operations;
3586 extern struct dentry *ext4_get_parent(struct dentry *child);
3587 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3588                                  struct ext4_dir_entry_2 *de,
3589                                  int blocksize, int csum_size,
3590                                  unsigned int parent_ino, int dotdot_real_len);
3591 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3592                                         unsigned int blocksize);
3593 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3594                                       struct buffer_head *bh);
3595 extern int __ext4_unlink(handle_t *handle, struct inode *dir, const struct qstr *d_name,
3596                          struct inode *inode);
3597 extern int __ext4_link(struct inode *dir, struct inode *inode,
3598                        struct dentry *dentry);
3599
3600 #define S_SHIFT 12
3601 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3602         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
3603         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
3604         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
3605         [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
3606         [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
3607         [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
3608         [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
3609 };
3610
3611 static inline void ext4_set_de_type(struct super_block *sb,
3612                                 struct ext4_dir_entry_2 *de,
3613                                 umode_t mode) {
3614         if (ext4_has_feature_filetype(sb))
3615                 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3616 }
3617
3618 /* readpages.c */
3619 extern int ext4_mpage_readpages(struct inode *inode,
3620                 struct readahead_control *rac, struct page *page);
3621 extern int __init ext4_init_post_read_processing(void);
3622 extern void ext4_exit_post_read_processing(void);
3623
3624 /* symlink.c */
3625 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3626 extern const struct inode_operations ext4_symlink_inode_operations;
3627 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3628
3629 /* sysfs.c */
3630 extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
3631 extern int ext4_register_sysfs(struct super_block *sb);
3632 extern void ext4_unregister_sysfs(struct super_block *sb);
3633 extern int __init ext4_init_sysfs(void);
3634 extern void ext4_exit_sysfs(void);
3635
3636 /* block_validity */
3637 extern void ext4_release_system_zone(struct super_block *sb);
3638 extern int ext4_setup_system_zone(struct super_block *sb);
3639 extern int __init ext4_init_system_zone(void);
3640 extern void ext4_exit_system_zone(void);
3641 extern int ext4_inode_block_valid(struct inode *inode,
3642                                   ext4_fsblk_t start_blk,
3643                                   unsigned int count);
3644 extern int ext4_check_blockref(const char *, unsigned int,
3645                                struct inode *, __le32 *, unsigned int);
3646
3647 /* extents.c */
3648 struct ext4_ext_path;
3649 struct ext4_extent;
3650
3651 /*
3652  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3653  * __le32.
3654  */
3655 #define EXT_MAX_BLOCKS  0xffffffff
3656
3657 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3658 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3659 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3660                                struct ext4_map_blocks *map, int flags);
3661 extern int ext4_ext_truncate(handle_t *, struct inode *);
3662 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3663                                  ext4_lblk_t end);
3664 extern void ext4_ext_init(struct super_block *);
3665 extern void ext4_ext_release(struct super_block *);
3666 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3667                           loff_t len);
3668 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3669                                           loff_t offset, ssize_t len);
3670 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3671                                              ext4_io_end_t *io_end);
3672 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3673                            struct ext4_map_blocks *map, int flags);
3674 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3675                                                    int num,
3676                                                    struct ext4_ext_path *path);
3677 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3678                                   struct ext4_ext_path **,
3679                                   struct ext4_extent *, int);
3680 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3681                                               struct ext4_ext_path **,
3682                                               int flags);
3683 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3684 extern int ext4_ext_check_inode(struct inode *inode);
3685 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3686 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3687                         __u64 start, __u64 len);
3688 extern int ext4_get_es_cache(struct inode *inode,
3689                              struct fiemap_extent_info *fieinfo,
3690                              __u64 start, __u64 len);
3691 extern int ext4_ext_precache(struct inode *inode);
3692 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3693                                 struct inode *inode2, ext4_lblk_t lblk1,
3694                              ext4_lblk_t lblk2,  ext4_lblk_t count,
3695                              int mark_unwritten,int *err);
3696 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3697 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3698                                        int check_cred, int restart_cred,
3699                                        int revoke_cred);
3700 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3701 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3702 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3703                 int len, int unwritten, ext4_fsblk_t pblk);
3704 extern int ext4_ext_clear_bb(struct inode *inode);
3705
3706
3707 /* move_extent.c */
3708 extern void ext4_double_down_write_data_sem(struct inode *first,
3709                                             struct inode *second);
3710 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3711                                           struct inode *donor_inode);
3712 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3713                              __u64 start_orig, __u64 start_donor,
3714                              __u64 len, __u64 *moved_len);
3715
3716 /* page-io.c */
3717 extern int __init ext4_init_pageio(void);
3718 extern void ext4_exit_pageio(void);
3719 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3720 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3721 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3722 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3723 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3724                                 struct writeback_control *wbc);
3725 extern void ext4_end_io_rsv_work(struct work_struct *work);
3726 extern void ext4_io_submit(struct ext4_io_submit *io);
3727 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3728                                struct page *page,
3729                                int len,
3730                                bool keep_towrite);
3731 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3732 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3733
3734 /* mmp.c */
3735 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3736
3737 /* mmp.c */
3738 extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
3739
3740 /* verity.c */
3741 extern const struct fsverity_operations ext4_verityops;
3742
3743 /*
3744  * Add new method to test whether block and inode bitmaps are properly
3745  * initialized. With uninit_bg reading the block from disk is not enough
3746  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3747  */
3748 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3749
3750 static inline int bitmap_uptodate(struct buffer_head *bh)
3751 {
3752         return (buffer_uptodate(bh) &&
3753                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3754 }
3755 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3756 {
3757         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3758 }
3759
3760 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
3761
3762 /* For ioend & aio unwritten conversion wait queues */
3763 #define EXT4_WQ_HASH_SZ         37
3764 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3765                                             EXT4_WQ_HASH_SZ])
3766 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3767
3768 extern int ext4_resize_begin(struct super_block *sb);
3769 extern void ext4_resize_end(struct super_block *sb);
3770
3771 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3772                                               struct ext4_io_end *io_end)
3773 {
3774         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3775                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
3776                 atomic_inc(&EXT4_I(inode)->i_unwritten);
3777         }
3778 }
3779
3780 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3781 {
3782         struct inode *inode = io_end->inode;
3783
3784         if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3785                 io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3786                 /* Wake up anyone waiting on unwritten extent conversion */
3787                 if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3788                         wake_up_all(ext4_ioend_wq(inode));
3789         }
3790 }
3791
3792 extern const struct iomap_ops ext4_iomap_ops;
3793 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3794 extern const struct iomap_ops ext4_iomap_report_ops;
3795
3796 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3797 {
3798         /*
3799          * If the buffer has the write error flag, we have failed
3800          * to write out data in the block.  In this  case, we don't
3801          * have to read the block because we may read the old data
3802          * successfully.
3803          */
3804         if (buffer_write_io_error(bh))
3805                 set_buffer_uptodate(bh);
3806         return buffer_uptodate(bh);
3807 }
3808
3809 #endif  /* __KERNEL__ */
3810
3811 #define EFSBADCRC       EBADMSG         /* Bad CRC detected */
3812 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
3813
3814 #endif  /* _EXT4_H */