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/refcount.h>
  21 #include <linux/types.h>
  22 #include <linux/blkdev.h>
  23 #include <linux/magic.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/quota.h>
  26 #include <linux/rwsem.h>
  27 #include <linux/rbtree.h>
  28 #include <linux/seqlock.h>
  29 #include <linux/mutex.h>
  30 #include <linux/timer.h>
  31 #include <linux/wait.h>
  32 #include <linux/sched/signal.h>
  33 #include <linux/blockgroup_lock.h>
  34 #include <linux/percpu_counter.h>
  35 #include <linux/ratelimit.h>
  36 #include <crypto/hash.h>
  37 #include <linux/falloc.h>
  38 #include <linux/percpu-rwsem.h>
  39 #include <linux/fiemap.h>
  40 #ifdef __KERNEL__
  41 #include <linux/compat.h>
  42 #endif
  43 #include <uapi/linux/ext4.h>
  44
  45 #include <linux/fscrypt.h>
  46 #include <linux/fsverity.h>
  47
  48 #include <linux/compiler.h>
  49
  50 /*
  51  * The fourth extended filesystem constants/structures
  52  */
  53
  54 /*
  55  * with AGGRESSIVE_CHECK allocator runs consistency checks over
  56  * structures. these checks slow things down a lot
  57  */
  58 #define AGGRESSIVE_CHECK__
  59
  60 /*
  61  * with DOUBLE_CHECK defined mballoc creates persistent in-core
  62  * bitmaps, maintains and uses them to check for double allocations
  63  */
  64 #define DOUBLE_CHECK__
  65
  66 /*
  67  * Define EXT4FS_DEBUG to produce debug messages
  68  */
  69 #undef EXT4FS_DEBUG
  70
  71 /*
  72  * Debug code
  73  */
  74 #ifdef EXT4FS_DEBUG
  75 #define ext4_debug(f, a...)                                             \
  76         do {                                                            \
  77                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  78                         __FILE__, __LINE__, __func__);                  \
  79                 printk(KERN_DEBUG f, ## a);                             \
  80         } while (0)
  81 #else
  82 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
  83 #endif
  84
  85  /*
  86   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
  87   */
  88 #define EXT_DEBUG__
  89
  90 /*
  91  * Dynamic printk for controlled extents debugging.
  92  */
  93 #ifdef CONFIG_EXT4_DEBUG
  94 #define ext_debug(ino, fmt, ...)                                        \
  95         pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,    \
  96                  current->comm, task_pid_nr(current),                   \
  97                  ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,       \
  98                  __func__, ##__VA_ARGS__)
  99 #else
 100 #define ext_debug(ino, fmt, ...)        no_printk(fmt, ##__VA_ARGS__)
 101 #endif
 102
 103 #define ASSERT(assert)                                          \
 104 do {                                                                    \
 105         if (unlikely(!(assert))) {                                      \
 106                 printk(KERN_EMERG                                       \
 107                        "Assertion failure in %s() at %s:%d: '%s'\n",    \
 108                        __func__, __FILE__, __LINE__, #assert);          \
 109                 BUG();                                                  \
 110         }                                                               \
 111 } while (0)
 112
 113 /* data type for block offset of block group */
 114 typedef int ext4_grpblk_t;
 115
 116 /* data type for filesystem-wide blocks number */
 117 typedef unsigned long long ext4_fsblk_t;
 118
 119 /* data type for file logical block number */
 120 typedef __u32 ext4_lblk_t;
 121
 122 /* data type for block group number */
 123 typedef unsigned int ext4_group_t;
 124
 125 enum SHIFT_DIRECTION {
 126         SHIFT_LEFT = 0,
 127         SHIFT_RIGHT,
 128 };
 129
 130 /*
 131  * Flags used in mballoc's allocation_context flags field.
 132  *
 133  * Also used to show what's going on for debugging purposes when the
 134  * flag field is exported via the traceport interface
 135  */
 136
 137 /* prefer goal again. length */
 138 #define EXT4_MB_HINT_MERGE              0x0001
 139 /* blocks already reserved */
 140 #define EXT4_MB_HINT_RESERVED           0x0002
 141 /* metadata is being allocated */
 142 #define EXT4_MB_HINT_METADATA           0x0004
 143 /* first blocks in the file */
 144 #define EXT4_MB_HINT_FIRST              0x0008
 145 /* search for the best chunk */
 146 #define EXT4_MB_HINT_BEST               0x0010
 147 /* data is being allocated */
 148 #define EXT4_MB_HINT_DATA               0x0020
 149 /* don't preallocate (for tails) */
 150 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 151 /* allocate for locality group */
 152 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 153 /* allocate goal blocks or none */
 154 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 155 /* goal is meaningful */
 156 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 157 /* blocks already pre-reserved by delayed allocation */
 158 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 159 /* We are doing stream allocation */
 160 #define EXT4_MB_STREAM_ALLOC            0x0800
 161 /* Use reserved root blocks if needed */
 162 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 163 /* Use blocks from reserved pool */
 164 #define EXT4_MB_USE_RESERVED            0x2000
 165 /* Do strict check for free blocks while retrying block allocation */
 166 #define EXT4_MB_STRICT_CHECK            0x4000
 167 /* Large fragment size list lookup succeeded at least once for cr = 0 */
 168 #define EXT4_MB_CR0_OPTIMIZED           0x8000
 169 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1 */
 170 #define EXT4_MB_CR1_OPTIMIZED           0x00010000
 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         refcount_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 == (1U << 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 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 596 struct compat_ext4_new_group_input {
 597         u32 group;
 598         compat_u64 block_bitmap;
 599         compat_u64 inode_bitmap;
 600         compat_u64 inode_table;
 601         u32 blocks_count;
 602         u16 reserved_blocks;
 603         u16 unused;
 604 };
 605 #endif
 606
 607 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 608 struct ext4_new_group_data {
 609         __u32 group;
 610         __u64 block_bitmap;
 611         __u64 inode_bitmap;
 612         __u64 inode_table;
 613         __u32 blocks_count;
 614         __u16 reserved_blocks;
 615         __u16 mdata_blocks;
 616         __u32 free_clusters_count;
 617 };
 618
 619 /* Indexes used to index group tables in ext4_new_group_data */
 620 enum {
 621         BLOCK_BITMAP = 0,       /* block bitmap */
 622         INODE_BITMAP,           /* inode bitmap */
 623         INODE_TABLE,            /* inode tables */
 624         GROUP_TABLE_COUNT,
 625 };
 626
 627 /*
 628  * Flags used by ext4_map_blocks()
 629  */
 630         /* Allocate any needed blocks and/or convert an unwritten
 631            extent to be an initialized ext4 */
 632 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 633         /* Request the creation of an unwritten extent */
 634 #define EXT4_GET_BLOCKS_UNWRIT_EXT              0x0002
 635 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT       (EXT4_GET_BLOCKS_UNWRIT_EXT|\
 636                                                  EXT4_GET_BLOCKS_CREATE)
 637         /* Caller is from the delayed allocation writeout path
 638          * finally doing the actual allocation of delayed blocks */
 639 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 640         /* caller is from the direct IO path, request to creation of an
 641         unwritten extents if not allocated, split the unwritten
 642         extent if blocks has been preallocated already*/
 643 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 644 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 645 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 646                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 647         /* Convert extent to initialized after IO complete */
 648 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 649                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 650         /* Eventual metadata allocation (due to growing extent tree)
 651          * should not fail, so try to use reserved blocks for that.*/
 652 #define EXT4_GET_BLOCKS_METADATA_NOFAIL         0x0020
 653         /* Don't normalize allocation size (used for fallocate) */
 654 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 655         /* Convert written extents to unwritten */
 656 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN       0x0100
 657         /* Write zeros to newly created written extents */
 658 #define EXT4_GET_BLOCKS_ZERO                    0x0200
 659 #define EXT4_GET_BLOCKS_CREATE_ZERO             (EXT4_GET_BLOCKS_CREATE |\
 660                                         EXT4_GET_BLOCKS_ZERO)
 661         /* Caller will submit data before dropping transaction handle. This
 662          * allows jbd2 to avoid submitting data before commit. */
 663 #define EXT4_GET_BLOCKS_IO_SUBMIT               0x0400
 664         /* Caller is in the atomic contex, find extent if it has been cached */
 665 #define EXT4_GET_BLOCKS_CACHED_NOWAIT           0x0800
 666
 667 /*
 668  * The bit position of these flags must not overlap with any of the
 669  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
 670  * read_extent_tree_block(), ext4_split_extent_at(),
 671  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
 672  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
 673  * caching the extents when reading from the extent tree while a
 674  * truncate or punch hole operation is in progress.
 675  */
 676 #define EXT4_EX_NOCACHE                         0x40000000
 677 #define EXT4_EX_FORCE_CACHE                     0x20000000
 678 #define EXT4_EX_NOFAIL                          0x10000000
 679
 680 /*
 681  * Flags used by ext4_free_blocks
 682  */
 683 #define EXT4_FREE_BLOCKS_METADATA               0x0001
 684 #define EXT4_FREE_BLOCKS_FORGET                 0x0002
 685 #define EXT4_FREE_BLOCKS_VALIDATED              0x0004
 686 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE         0x0008
 687 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 688 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 689 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
 690
 691 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 692 /*
 693  * ioctl commands in 32 bit emulation
 694  */
 695 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 696 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 697 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 698 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 699 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 700 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 701 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 702 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 703 #endif
 704
 705 /* Max physical block we can address w/o extents */
 706 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 707
 708 /* Max logical block we can support */
 709 #define EXT4_MAX_LOGICAL_BLOCK          0xFFFFFFFE
 710
 711 /*
 712  * Structure of an inode on the disk
 713  */
 714 struct ext4_inode {
 715         __le16  i_mode;         /* File mode */
 716         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 717         __le32  i_size_lo;      /* Size in bytes */
 718         __le32  i_atime;        /* Access time */
 719         __le32  i_ctime;        /* Inode Change time */
 720         __le32  i_mtime;        /* Modification time */
 721         __le32  i_dtime;        /* Deletion Time */
 722         __le16  i_gid;          /* Low 16 bits of Group Id */
 723         __le16  i_links_count;  /* Links count */
 724         __le32  i_blocks_lo;    /* Blocks count */
 725         __le32  i_flags;        /* File flags */
 726         union {
 727                 struct {
 728                         __le32  l_i_version;
 729                 } linux1;
 730                 struct {
 731                         __u32  h_i_translator;
 732                 } hurd1;
 733                 struct {
 734                         __u32  m_i_reserved1;
 735                 } masix1;
 736         } osd1;                         /* OS dependent 1 */
 737         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 738         __le32  i_generation;   /* File version (for NFS) */
 739         __le32  i_file_acl_lo;  /* File ACL */
 740         __le32  i_size_high;
 741         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 742         union {
 743                 struct {
 744                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 745                         __le16  l_i_file_acl_high;
 746                         __le16  l_i_uid_high;   /* these 2 fields */
 747                         __le16  l_i_gid_high;   /* were reserved2[0] */
 748                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 749                         __le16  l_i_reserved;
 750                 } linux2;
 751                 struct {
 752                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 753                         __u16   h_i_mode_high;
 754                         __u16   h_i_uid_high;
 755                         __u16   h_i_gid_high;
 756                         __u32   h_i_author;
 757                 } hurd2;
 758                 struct {
 759                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 760                         __le16  m_i_file_acl_high;
 761                         __u32   m_i_reserved2[2];
 762                 } masix2;
 763         } osd2;                         /* OS dependent 2 */
 764         __le16  i_extra_isize;
 765         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 766         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 767         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 768         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 769         __le32  i_crtime;       /* File Creation time */
 770         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 771         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 772         __le32  i_projid;       /* Project ID */
 773 };
 774
 775 #define EXT4_EPOCH_BITS 2
 776 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 777 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 778
 779 /*
 780  * Extended fields will fit into an inode if the filesystem was formatted
 781  * with large inodes (-I 256 or larger) and there are not currently any EAs
 782  * consuming all of the available space. For new inodes we always reserve
 783  * enough space for the kernel's known extended fields, but for inodes
 784  * created with an old kernel this might not have been the case. None of
 785  * the extended inode fields is critical for correct filesystem operation.
 786  * This macro checks if a certain field fits in the inode. Note that
 787  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 788  */
 789 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 790         ((offsetof(typeof(*ext4_inode), field) +        \
 791           sizeof((ext4_inode)->field))                  \
 792         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 793             (einode)->i_extra_isize))                   \
 794
 795 /*
 796  * We use an encoding that preserves the times for extra epoch "00":
 797  *
 798  * extra  msb of                         adjust for signed
 799  * epoch  32-bit                         32-bit tv_sec to
 800  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
 801  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
 802  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
 803  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
 804  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
 805  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
 806  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
 807  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
 808  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
 809  *
 810  * Note that previous versions of the kernel on 64-bit systems would
 811  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
 812  * 1970.  e2fsck will correct this, assuming that it is run on the
 813  * affected filesystem before 2242.
 814  */
 815
 816 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
 817 {
 818         u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
 819         return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
 820 }
 821
 822 static inline void ext4_decode_extra_time(struct timespec64 *time,
 823                                           __le32 extra)
 824 {
 825         if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
 826                 time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
 827         time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 828 }
 829
 830 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                           \
 831 do {                                                                            \
 832         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
 833                 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);        \
 834                 (raw_inode)->xtime ## _extra =                                  \
 835                                 ext4_encode_extra_time(&(inode)->xtime);        \
 836                 }                                                               \
 837         else    \
 838                 (raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));    \
 839 } while (0)
 840
 841 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 842 do {                                                                           \
 843         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 844                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 845         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 846                 (raw_inode)->xtime ## _extra =                                 \
 847                                 ext4_encode_extra_time(&(einode)->xtime);      \
 848 } while (0)
 849
 850 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                           \
 851 do {                                                                            \
 852         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);        \
 853         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {    \
 854                 ext4_decode_extra_time(&(inode)->xtime,                         \
 855                                        raw_inode->xtime ## _extra);             \
 856                 }                                                               \
 857         else                                                                    \
 858                 (inode)->xtime.tv_nsec = 0;                                     \
 859 } while (0)
 860
 861
 862 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 863 do {                                                                           \
 864         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 865                 (einode)->xtime.tv_sec =                                       \
 866                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 867         else                                                                   \
 868                 (einode)->xtime.tv_sec = 0;                                    \
 869         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 870                 ext4_decode_extra_time(&(einode)->xtime,                       \
 871                                        raw_inode->xtime ## _extra);            \
 872         else                                                                   \
 873                 (einode)->xtime.tv_nsec = 0;                                   \
 874 } while (0)
 875
 876 #define i_disk_version osd1.linux1.l_i_version
 877
 878 #if defined(__KERNEL__) || defined(__linux__)
 879 #define i_reserved1     osd1.linux1.l_i_reserved1
 880 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 881 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 882 #define i_uid_low       i_uid
 883 #define i_gid_low       i_gid
 884 #define i_uid_high      osd2.linux2.l_i_uid_high
 885 #define i_gid_high      osd2.linux2.l_i_gid_high
 886 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 887
 888 #elif defined(__GNU__)
 889
 890 #define i_translator    osd1.hurd1.h_i_translator
 891 #define i_uid_high      osd2.hurd2.h_i_uid_high
 892 #define i_gid_high      osd2.hurd2.h_i_gid_high
 893 #define i_author        osd2.hurd2.h_i_author
 894
 895 #elif defined(__masix__)
 896
 897 #define i_reserved1     osd1.masix1.m_i_reserved1
 898 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 899 #define i_reserved2     osd2.masix2.m_i_reserved2
 900
 901 #endif /* defined(__KERNEL__) || defined(__linux__) */
 902
 903 #include "extents_status.h"
 904 #include "fast_commit.h"
 905
 906 /*
 907  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
 908  *
 909  * These are needed to avoid lockdep false positives when we need to
 910  * allocate blocks to the quota inode during ext4_map_blocks(), while
 911  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
 912  * do quota tracking for the quota inode, this avoids deadlock (as
 913  * well as infinite recursion, since it isn't turtles all the way
 914  * down...)
 915  *
 916  *  I_DATA_SEM_NORMAL - Used for most inodes
 917  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
 918  *                        where the second inode has larger inode number
 919  *                        than the first
 920  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
 921  */
 922 enum {
 923         I_DATA_SEM_NORMAL = 0,
 924         I_DATA_SEM_OTHER,
 925         I_DATA_SEM_QUOTA,
 926 };
 927
 928
 929 /*
 930  * fourth extended file system inode data in memory
 931  */
 932 struct ext4_inode_info {
 933         __le32  i_data[15];     /* unconverted */
 934         __u32   i_dtime;
 935         ext4_fsblk_t    i_file_acl;
 936
 937         /*
 938          * i_block_group is the number of the block group which contains
 939          * this file's inode.  Constant across the lifetime of the inode,
 940          * it is used for making block allocation decisions - we try to
 941          * place a file's data blocks near its inode block, and new inodes
 942          * near to their parent directory's inode.
 943          */
 944         ext4_group_t    i_block_group;
 945         ext4_lblk_t     i_dir_start_lookup;
 946 #if (BITS_PER_LONG < 64)
 947         unsigned long   i_state_flags;          /* Dynamic state flags */
 948 #endif
 949         unsigned long   i_flags;
 950
 951         /*
 952          * Extended attributes can be read independently of the main file
 953          * data. Taking i_rwsem even when reading would cause contention
 954          * between readers of EAs and writers of regular file data, so
 955          * instead we synchronize on xattr_sem when reading or changing
 956          * EAs.
 957          */
 958         struct rw_semaphore xattr_sem;
 959
 960         /*
 961          * Inodes with EXT4_STATE_ORPHAN_FILE use i_orphan_idx. Otherwise
 962          * i_orphan is used.
 963          */
 964         union {
 965                 struct list_head i_orphan;      /* unlinked but open inodes */
 966                 unsigned int i_orphan_idx;      /* Index in orphan file */
 967         };
 968
 969         /* Fast commit related info */
 970
 971         /* For tracking dentry create updates */
 972         struct list_head i_fc_dilist;
 973         struct list_head i_fc_list;     /*
 974                                          * inodes that need fast commit
 975                                          * protected by sbi->s_fc_lock.
 976                                          */
 977
 978         /* Start of lblk range that needs to be committed in this fast commit */
 979         ext4_lblk_t i_fc_lblk_start;
 980
 981         /* End of lblk range that needs to be committed in this fast commit */
 982         ext4_lblk_t i_fc_lblk_len;
 983
 984         /* Number of ongoing updates on this inode */
 985         atomic_t  i_fc_updates;
 986
 987         /* Fast commit wait queue for this inode */
 988         wait_queue_head_t i_fc_wait;
 989
 990         /* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
 991         struct mutex i_fc_lock;
 992
 993         /*
 994          * i_disksize keeps track of what the inode size is ON DISK, not
 995          * in memory.  During truncate, i_size is set to the new size by
 996          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 997          * set i_disksize to 0 until the truncate is actually under way.
 998          *
 999          * The intent is that i_disksize always represents the blocks which
1000          * are used by this file.  This allows recovery to restart truncate
1001          * on orphans if we crash during truncate.  We actually write i_disksize
1002          * into the on-disk inode when writing inodes out, instead of i_size.
1003          *
1004          * The only time when i_disksize and i_size may be different is when
1005          * a truncate is in progress.  The only things which change i_disksize
1006          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1007          */
1008         loff_t  i_disksize;
1009
1010         /*
1011          * i_data_sem is for serialising ext4_truncate() against
1012          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1013          * data tree are chopped off during truncate. We can't do that in
1014          * ext4 because whenever we perform intermediate commits during
1015          * truncate, the inode and all the metadata blocks *must* be in a
1016          * consistent state which allows truncation of the orphans to restart
1017          * during recovery.  Hence we must fix the get_block-vs-truncate race
1018          * by other means, so we have i_data_sem.
1019          */
1020         struct rw_semaphore i_data_sem;
1021         struct inode vfs_inode;
1022         struct jbd2_inode *jinode;
1023
1024         spinlock_t i_raw_lock;  /* protects updates to the raw inode */
1025
1026         /*
1027          * File creation time. Its function is same as that of
1028          * struct timespec64 i_{a,c,m}time in the generic inode.
1029          */
1030         struct timespec64 i_crtime;
1031
1032         /* mballoc */
1033         atomic_t i_prealloc_active;
1034         struct rb_root i_prealloc_node;
1035         rwlock_t i_prealloc_lock;
1036
1037         /* extents status tree */
1038         struct ext4_es_tree i_es_tree;
1039         rwlock_t i_es_lock;
1040         struct list_head i_es_list;
1041         unsigned int i_es_all_nr;       /* protected by i_es_lock */
1042         unsigned int i_es_shk_nr;       /* protected by i_es_lock */
1043         ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
1044                                            extents to shrink. Protected by
1045                                            i_es_lock  */
1046
1047         /* ialloc */
1048         ext4_group_t    i_last_alloc_group;
1049
1050         /* allocation reservation info for delalloc */
1051         /* In case of bigalloc, this refer to clusters rather than blocks */
1052         unsigned int i_reserved_data_blocks;
1053
1054         /* pending cluster reservations for bigalloc file systems */
1055         struct ext4_pending_tree i_pending_tree;
1056
1057         /* on-disk additional length */
1058         __u16 i_extra_isize;
1059
1060         /* Indicate the inline data space. */
1061         u16 i_inline_off;
1062         u16 i_inline_size;
1063
1064 #ifdef CONFIG_QUOTA
1065         /* quota space reservation, managed internally by quota code */
1066         qsize_t i_reserved_quota;
1067 #endif
1068
1069         /* Lock protecting lists below */
1070         spinlock_t i_completed_io_lock;
1071         /*
1072          * Completed IOs that need unwritten extents handling and have
1073          * transaction reserved
1074          */
1075         struct list_head i_rsv_conversion_list;
1076         struct work_struct i_rsv_conversion_work;
1077         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1078
1079         spinlock_t i_block_reservation_lock;
1080
1081         /*
1082          * Transactions that contain inode's metadata needed to complete
1083          * fsync and fdatasync, respectively.
1084          */
1085         tid_t i_sync_tid;
1086         tid_t i_datasync_tid;
1087
1088 #ifdef CONFIG_QUOTA
1089         struct dquot *i_dquot[MAXQUOTAS];
1090 #endif
1091
1092         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1093         __u32 i_csum_seed;
1094
1095         kprojid_t i_projid;
1096 };
1097
1098 /*
1099  * File system states
1100  */
1101 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
1102 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
1103 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
1104 #define EXT4_FC_REPLAY                  0x0020  /* Fast commit replay ongoing */
1105
1106 /*
1107  * Misc. filesystem flags
1108  */
1109 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
1110 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
1111 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
1112
1113 /*
1114  * Mount flags set via mount options or defaults
1115  */
1116 #define EXT4_MOUNT_NO_MBCACHE           0x00001 /* Do not use mbcache */
1117 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
1118 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
1119 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
1120 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
1121 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
1122 #define EXT4_MOUNT_ERRORS_MASK          0x00070
1123 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
1124 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
1125 #ifdef CONFIG_FS_DAX
1126 #define EXT4_MOUNT_DAX_ALWAYS           0x00200 /* Direct Access */
1127 #else
1128 #define EXT4_MOUNT_DAX_ALWAYS           0
1129 #endif
1130 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
1131 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
1132 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
1133 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
1134 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
1135 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
1136 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
1137 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
1138 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
1139 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
1140 #define EXT4_MOUNT_QUOTA                0x40000 /* Some quota option set */
1141 #define EXT4_MOUNT_USRQUOTA             0x80000 /* "old" user quota,
1142                                                  * enable enforcement for hidden
1143                                                  * quota files */
1144 #define EXT4_MOUNT_GRPQUOTA             0x100000 /* "old" group quota, enable
1145                                                   * enforcement for hidden quota
1146                                                   * files */
1147 #define EXT4_MOUNT_PRJQUOTA             0x200000 /* Enable project quota
1148                                                   * enforcement */
1149 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
1150 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
1151 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
1152 #define EXT4_MOUNT_WARN_ON_ERROR        0x2000000 /* Trigger WARN_ON on error */
1153 #define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
1154 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
1155 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
1156 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
1157 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
1158 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
1159
1160 /*
1161  * Mount flags set either automatically (could not be set by mount option)
1162  * based on per file system feature or property or in special cases such as
1163  * distinguishing between explicit mount option definition and default.
1164  */
1165 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1166                                                       specified delalloc */
1167 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
1168                                                       size of blocksize * 8
1169                                                       blocks */
1170 #define EXT4_MOUNT2_HURD_COMPAT         0x00000004 /* Support HURD-castrated
1171                                                       file systems */
1172 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM   0x00000008 /* User explicitly
1173                                                 specified journal checksum */
1174
1175 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT 0x00000010 /* Journal fast commit */
1176 #define EXT4_MOUNT2_DAX_NEVER           0x00000020 /* Do not allow Direct Access */
1177 #define EXT4_MOUNT2_DAX_INODE           0x00000040 /* For printing options only */
1178 #define EXT4_MOUNT2_MB_OPTIMIZE_SCAN    0x00000080 /* Optimize group
1179                                                     * scanning in mballoc
1180                                                     */
1181
1182 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1183                                                 ~EXT4_MOUNT_##opt
1184 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1185                                                 EXT4_MOUNT_##opt
1186 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1187                                          EXT4_MOUNT_##opt)
1188
1189 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1190                                                 ~EXT4_MOUNT2_##opt
1191 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1192                                                 EXT4_MOUNT2_##opt
1193 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1194                                          EXT4_MOUNT2_##opt)
1195
1196 #define ext4_test_and_set_bit           __test_and_set_bit_le
1197 #define ext4_set_bit                    __set_bit_le
1198 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1199 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1200 #define ext4_clear_bit                  __clear_bit_le
1201 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1202 #define ext4_test_bit                   test_bit_le
1203 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1204 #define ext4_find_next_bit              find_next_bit_le
1205
1206 extern void mb_set_bits(void *bm, int cur, int len);
1207
1208 /*
1209  * Maximal mount counts between two filesystem checks
1210  */
1211 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1212 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1213
1214 /*
1215  * Behaviour when detecting errors
1216  */
1217 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1218 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1219 #define EXT4_ERRORS_PANIC               3       /* Panic */
1220 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1221
1222 /* Metadata checksum algorithm codes */
1223 #define EXT4_CRC32C_CHKSUM              1
1224
1225 #define EXT4_LABEL_MAX                  16
1226
1227 /*
1228  * Structure of the super block
1229  */
1230 struct ext4_super_block {
1231 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1232         __le32  s_blocks_count_lo;      /* Blocks count */
1233         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1234         __le32  s_free_blocks_count_lo; /* Free blocks count */
1235 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1236         __le32  s_first_data_block;     /* First Data Block */
1237         __le32  s_log_block_size;       /* Block size */
1238         __le32  s_log_cluster_size;     /* Allocation cluster size */
1239 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1240         __le32  s_clusters_per_group;   /* # Clusters per group */
1241         __le32  s_inodes_per_group;     /* # Inodes per group */
1242         __le32  s_mtime;                /* Mount time */
1243 /*30*/  __le32  s_wtime;                /* Write time */
1244         __le16  s_mnt_count;            /* Mount count */
1245         __le16  s_max_mnt_count;        /* Maximal mount count */
1246         __le16  s_magic;                /* Magic signature */
1247         __le16  s_state;                /* File system state */
1248         __le16  s_errors;               /* Behaviour when detecting errors */
1249         __le16  s_minor_rev_level;      /* minor revision level */
1250 /*40*/  __le32  s_lastcheck;            /* time of last check */
1251         __le32  s_checkinterval;        /* max. time between checks */
1252         __le32  s_creator_os;           /* OS */
1253         __le32  s_rev_level;            /* Revision level */
1254 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1255         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1256         /*
1257          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1258          *
1259          * Note: the difference between the compatible feature set and
1260          * the incompatible feature set is that if there is a bit set
1261          * in the incompatible feature set that the kernel doesn't
1262          * know about, it should refuse to mount the filesystem.
1263          *
1264          * e2fsck's requirements are more strict; if it doesn't know
1265          * about a feature in either the compatible or incompatible
1266          * feature set, it must abort and not try to meddle with
1267          * things it doesn't understand...
1268          */
1269         __le32  s_first_ino;            /* First non-reserved inode */
1270         __le16  s_inode_size;           /* size of inode structure */
1271         __le16  s_block_group_nr;       /* block group # of this superblock */
1272         __le32  s_feature_compat;       /* compatible feature set */
1273 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1274         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1275 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1276 /*78*/  char    s_volume_name[EXT4_LABEL_MAX];  /* volume name */
1277 /*88*/  char    s_last_mounted[64] __nonstring; /* directory where last mounted */
1278 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1279         /*
1280          * Performance hints.  Directory preallocation should only
1281          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1282          */
1283         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1284         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1285         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1286         /*
1287          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1288          */
1289 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1290 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1291         __le32  s_journal_dev;          /* device number of journal file */
1292         __le32  s_last_orphan;          /* start of list of inodes to delete */
1293         __le32  s_hash_seed[4];         /* HTREE hash seed */
1294         __u8    s_def_hash_version;     /* Default hash version to use */
1295         __u8    s_jnl_backup_type;
1296         __le16  s_desc_size;            /* size of group descriptor */
1297 /*100*/ __le32  s_default_mount_opts;
1298         __le32  s_first_meta_bg;        /* First metablock block group */
1299         __le32  s_mkfs_time;            /* When the filesystem was created */
1300         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1301         /* 64bit support valid if EXT4_FEATURE_INCOMPAT_64BIT */
1302 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1303         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1304         __le32  s_free_blocks_count_hi; /* Free blocks count */
1305         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1306         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1307         __le32  s_flags;                /* Miscellaneous flags */
1308         __le16  s_raid_stride;          /* RAID stride */
1309         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1310         __le64  s_mmp_block;            /* Block for multi-mount protection */
1311         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1312         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1313         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1314         __u8    s_encryption_level;     /* versioning level for encryption */
1315         __u8    s_reserved_pad;         /* Padding to next 32bits */
1316         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1317         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1318         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1319         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1320                                               snapshot's future use */
1321         __le32  s_snapshot_list;        /* inode number of the head of the
1322                                            on-disk snapshot list */
1323 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1324         __le32  s_error_count;          /* number of fs errors */
1325         __le32  s_first_error_time;     /* first time an error happened */
1326         __le32  s_first_error_ino;      /* inode involved in first error */
1327         __le64  s_first_error_block;    /* block involved of first error */
1328         __u8    s_first_error_func[32] __nonstring;     /* function where the error happened */
1329         __le32  s_first_error_line;     /* line number where error happened */
1330         __le32  s_last_error_time;      /* most recent time of an error */
1331         __le32  s_last_error_ino;       /* inode involved in last error */
1332         __le32  s_last_error_line;      /* line number where error happened */
1333         __le64  s_last_error_block;     /* block involved of last error */
1334         __u8    s_last_error_func[32] __nonstring;      /* function where the error happened */
1335 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1336         __u8    s_mount_opts[64];
1337         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1338         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1339         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1340         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
1341         __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
1342         __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
1343         __le32  s_lpf_ino;              /* Location of the lost+found inode */
1344         __le32  s_prj_quota_inum;       /* inode for tracking project quota */
1345         __le32  s_checksum_seed;        /* crc32c(uuid) if csum_seed set */
1346         __u8    s_wtime_hi;
1347         __u8    s_mtime_hi;
1348         __u8    s_mkfs_time_hi;
1349         __u8    s_lastcheck_hi;
1350         __u8    s_first_error_time_hi;
1351         __u8    s_last_error_time_hi;
1352         __u8    s_first_error_errcode;
1353         __u8    s_last_error_errcode;
1354         __le16  s_encoding;             /* Filename charset encoding */
1355         __le16  s_encoding_flags;       /* Filename charset encoding flags */
1356         __le32  s_orphan_file_inum;     /* Inode for tracking orphan inodes */
1357         __le32  s_reserved[94];         /* Padding to the end of the block */
1358         __le32  s_checksum;             /* crc32c(superblock) */
1359 };
1360
1361 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1362
1363 #ifdef __KERNEL__
1364
1365 /* Number of quota types we support */
1366 #define EXT4_MAXQUOTAS 3
1367
1368 #define EXT4_ENC_UTF8_12_1      1
1369
1370 /* Types of ext4 journal triggers */
1371 enum ext4_journal_trigger_type {
1372         EXT4_JTR_ORPHAN_FILE,
1373         EXT4_JTR_NONE   /* This must be the last entry for indexing to work! */
1374 };
1375
1376 #define EXT4_JOURNAL_TRIGGER_COUNT EXT4_JTR_NONE
1377
1378 struct ext4_journal_trigger {
1379         struct jbd2_buffer_trigger_type tr_triggers;
1380         struct super_block *sb;
1381 };
1382
1383 static inline struct ext4_journal_trigger *EXT4_TRIGGER(
1384                                 struct jbd2_buffer_trigger_type *trigger)
1385 {
1386         return container_of(trigger, struct ext4_journal_trigger, tr_triggers);
1387 }
1388
1389 #define EXT4_ORPHAN_BLOCK_MAGIC 0x0b10ca04
1390
1391 /* Structure at the tail of orphan block */
1392 struct ext4_orphan_block_tail {
1393         __le32 ob_magic;
1394         __le32 ob_checksum;
1395 };
1396
1397 static inline int ext4_inodes_per_orphan_block(struct super_block *sb)
1398 {
1399         return (sb->s_blocksize - sizeof(struct ext4_orphan_block_tail)) /
1400                         sizeof(u32);
1401 }
1402
1403 struct ext4_orphan_block {
1404         atomic_t ob_free_entries;       /* Number of free orphan entries in block */
1405         struct buffer_head *ob_bh;      /* Buffer for orphan block */
1406 };
1407
1408 /*
1409  * Info about orphan file.
1410  */
1411 struct ext4_orphan_info {
1412         int of_blocks;                  /* Number of orphan blocks in a file */
1413         __u32 of_csum_seed;             /* Checksum seed for orphan file */
1414         struct ext4_orphan_block *of_binfo;     /* Array with info about orphan
1415                                                  * file blocks */
1416 };
1417
1418 /*
1419  * fourth extended-fs super-block data in memory
1420  */
1421 struct ext4_sb_info {
1422         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1423         unsigned long s_inodes_per_block;/* Number of inodes per block */
1424         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1425         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1426         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1427         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1428         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1429         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1430         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1431         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1432         unsigned long s_overhead;  /* # of fs overhead clusters */
1433         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1434         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1435         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1436         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1437         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1438         struct buffer_head * __rcu *s_group_desc;
1439         unsigned int s_mount_opt;
1440         unsigned int s_mount_opt2;
1441         unsigned long s_mount_flags;
1442         unsigned int s_def_mount_opt;
1443         unsigned int s_def_mount_opt2;
1444         ext4_fsblk_t s_sb_block;
1445         atomic64_t s_resv_clusters;
1446         kuid_t s_resuid;
1447         kgid_t s_resgid;
1448         unsigned short s_mount_state;
1449         unsigned short s_pad;
1450         int s_addr_per_block_bits;
1451         int s_desc_per_block_bits;
1452         int s_inode_size;
1453         int s_first_ino;
1454         unsigned int s_inode_readahead_blks;
1455         unsigned int s_inode_goal;
1456         u32 s_hash_seed[4];
1457         int s_def_hash_version;
1458         int s_hash_unsigned;    /* 3 if hash should be unsigned, 0 if not */
1459         struct percpu_counter s_freeclusters_counter;
1460         struct percpu_counter s_freeinodes_counter;
1461         struct percpu_counter s_dirs_counter;
1462         struct percpu_counter s_dirtyclusters_counter;
1463         struct percpu_counter s_sra_exceeded_retry_limit;
1464         struct blockgroup_lock *s_blockgroup_lock;
1465         struct proc_dir_entry *s_proc;
1466         struct kobject s_kobj;
1467         struct completion s_kobj_unregister;
1468         struct super_block *s_sb;
1469         struct buffer_head *s_mmp_bh;
1470
1471         /* Journaling */
1472         struct journal_s *s_journal;
1473         unsigned long s_ext4_flags;             /* Ext4 superblock flags */
1474         struct mutex s_orphan_lock;     /* Protects on disk list changes */
1475         struct list_head s_orphan;      /* List of orphaned inodes in on disk
1476                                            list */
1477         struct ext4_orphan_info s_orphan_info;
1478         unsigned long s_commit_interval;
1479         u32 s_max_batch_time;
1480         u32 s_min_batch_time;
1481         struct block_device *s_journal_bdev;
1482 #ifdef CONFIG_QUOTA
1483         /* Names of quota files with journalled quota */
1484         char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1485         int s_jquota_fmt;                       /* Format of quota to use */
1486 #endif
1487         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1488         struct ext4_system_blocks __rcu *s_system_blks;
1489
1490 #ifdef EXTENTS_STATS
1491         /* ext4 extents stats */
1492         unsigned long s_ext_min;
1493         unsigned long s_ext_max;
1494         unsigned long s_depth_max;
1495         spinlock_t s_ext_stats_lock;
1496         unsigned long s_ext_blocks;
1497         unsigned long s_ext_extents;
1498 #endif
1499
1500         /* for buddy allocator */
1501         struct ext4_group_info ** __rcu *s_group_info;
1502         struct inode *s_buddy_cache;
1503         spinlock_t s_md_lock;
1504         unsigned short *s_mb_offsets;
1505         unsigned int *s_mb_maxs;
1506         unsigned int s_group_info_size;
1507         unsigned int s_mb_free_pending;
1508         struct list_head s_freed_data_list;     /* List of blocks to be freed
1509                                                    after commit completed */
1510         struct list_head s_discard_list;
1511         struct work_struct s_discard_work;
1512         atomic_t s_retry_alloc_pending;
1513         struct list_head *s_mb_avg_fragment_size;
1514         rwlock_t *s_mb_avg_fragment_size_locks;
1515         struct list_head *s_mb_largest_free_orders;
1516         rwlock_t *s_mb_largest_free_orders_locks;
1517
1518         /* tunables */
1519         unsigned long s_stripe;
1520         unsigned int s_mb_max_linear_groups;
1521         unsigned int s_mb_stream_request;
1522         unsigned int s_mb_max_to_scan;
1523         unsigned int s_mb_min_to_scan;
1524         unsigned int s_mb_stats;
1525         unsigned int s_mb_order2_reqs;
1526         unsigned int s_mb_group_prealloc;
1527         unsigned int s_max_dir_size_kb;
1528         /* where last allocation was done - for stream allocation */
1529         unsigned long s_mb_last_group;
1530         unsigned long s_mb_last_start;
1531         unsigned int s_mb_prefetch;
1532         unsigned int s_mb_prefetch_limit;
1533
1534         /* stats for buddy allocator */
1535         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1536         atomic_t s_bal_success; /* we found long enough chunks */
1537         atomic_t s_bal_allocated;       /* in blocks */
1538         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1539         atomic_t s_bal_groups_scanned;  /* number of groups scanned */
1540         atomic_t s_bal_goals;   /* goal hits */
1541         atomic_t s_bal_breaks;  /* too long searches */
1542         atomic_t s_bal_2orders; /* 2^order hits */
1543         atomic_t s_bal_cr0_bad_suggestions;
1544         atomic_t s_bal_cr1_bad_suggestions;
1545         atomic64_t s_bal_cX_groups_considered[4];
1546         atomic64_t s_bal_cX_hits[4];
1547         atomic64_t s_bal_cX_failed[4];          /* cX loop didn't find blocks */
1548         atomic_t s_mb_buddies_generated;        /* number of buddies generated */
1549         atomic64_t s_mb_generation_time;
1550         atomic_t s_mb_lost_chunks;
1551         atomic_t s_mb_preallocated;
1552         atomic_t s_mb_discarded;
1553         atomic_t s_lock_busy;
1554
1555         /* locality groups */
1556         struct ext4_locality_group __percpu *s_locality_groups;
1557
1558         /* for write statistics */
1559         unsigned long s_sectors_written_start;
1560         u64 s_kbytes_written;
1561
1562         /* the size of zero-out chunk */
1563         unsigned int s_extent_max_zeroout_kb;
1564
1565         unsigned int s_log_groups_per_flex;
1566         struct flex_groups * __rcu *s_flex_groups;
1567         ext4_group_t s_flex_groups_allocated;
1568
1569         /* workqueue for reserved extent conversions (buffered io) */
1570         struct workqueue_struct *rsv_conversion_wq;
1571
1572         /* timer for periodic error stats printing */
1573         struct timer_list s_err_report;
1574
1575         /* Lazy inode table initialization info */
1576         struct ext4_li_request *s_li_request;
1577         /* Wait multiplier for lazy initialization thread */
1578         unsigned int s_li_wait_mult;
1579
1580         /* Kernel thread for multiple mount protection */
1581         struct task_struct *s_mmp_tsk;
1582
1583         /* record the last minlen when FITRIM is called. */
1584         unsigned long s_last_trim_minblks;
1585
1586         /* Reference to checksum algorithm driver via cryptoapi */
1587         struct crypto_shash *s_chksum_driver;
1588
1589         /* Precomputed FS UUID checksum for seeding other checksums */
1590         __u32 s_csum_seed;
1591
1592         /* Reclaim extents from extent status tree */
1593         struct shrinker s_es_shrinker;
1594         struct list_head s_es_list;     /* List of inodes with reclaimable extents */
1595         long s_es_nr_inode;
1596         struct ext4_es_stats s_es_stats;
1597         struct mb_cache *s_ea_block_cache;
1598         struct mb_cache *s_ea_inode_cache;
1599         spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1600
1601         /* Journal triggers for checksum computation */
1602         struct ext4_journal_trigger s_journal_triggers[EXT4_JOURNAL_TRIGGER_COUNT];
1603
1604         /* Ratelimit ext4 messages. */
1605         struct ratelimit_state s_err_ratelimit_state;
1606         struct ratelimit_state s_warning_ratelimit_state;
1607         struct ratelimit_state s_msg_ratelimit_state;
1608         atomic_t s_warning_count;
1609         atomic_t s_msg_count;
1610
1611         /* Encryption policy for '-o test_dummy_encryption' */
1612         struct fscrypt_dummy_policy s_dummy_enc_policy;
1613
1614         /*
1615          * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1616          * or EXTENTS flag.
1617          */
1618         struct percpu_rw_semaphore s_writepages_rwsem;
1619         struct dax_device *s_daxdev;
1620         u64 s_dax_part_off;
1621 #ifdef CONFIG_EXT4_DEBUG
1622         unsigned long s_simulate_fail;
1623 #endif
1624         /* Record the errseq of the backing block device */
1625         errseq_t s_bdev_wb_err;
1626         spinlock_t s_bdev_wb_lock;
1627
1628         /* Information about errors that happened during this mount */
1629         spinlock_t s_error_lock;
1630         int s_add_error_count;
1631         int s_first_error_code;
1632         __u32 s_first_error_line;
1633         __u32 s_first_error_ino;
1634         __u64 s_first_error_block;
1635         const char *s_first_error_func;
1636         time64_t s_first_error_time;
1637         int s_last_error_code;
1638         __u32 s_last_error_line;
1639         __u32 s_last_error_ino;
1640         __u64 s_last_error_block;
1641         const char *s_last_error_func;
1642         time64_t s_last_error_time;
1643         /*
1644          * If we are in a context where we cannot update error information in
1645          * the on-disk superblock, we queue this work to do it.
1646          */
1647         struct work_struct s_error_work;
1648
1649         /* Ext4 fast commit sub transaction ID */
1650         atomic_t s_fc_subtid;
1651
1652         /*
1653          * After commit starts, the main queue gets locked, and the further
1654          * updates get added in the staging queue.
1655          */
1656 #define FC_Q_MAIN       0
1657 #define FC_Q_STAGING    1
1658         struct list_head s_fc_q[2];     /* Inodes staged for fast commit
1659                                          * that have data changes in them.
1660                                          */
1661         struct list_head s_fc_dentry_q[2];      /* directory entry updates */
1662         unsigned int s_fc_bytes;
1663         /*
1664          * Main fast commit lock. This lock protects accesses to the
1665          * following fields:
1666          * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1667          */
1668         spinlock_t s_fc_lock;
1669         struct buffer_head *s_fc_bh;
1670         struct ext4_fc_stats s_fc_stats;
1671         tid_t s_fc_ineligible_tid;
1672 #ifdef CONFIG_EXT4_DEBUG
1673         int s_fc_debug_max_replay;
1674 #endif
1675         struct ext4_fc_replay_state s_fc_replay_state;
1676 };
1677
1678 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1679 {
1680         return sb->s_fs_info;
1681 }
1682 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1683 {
1684         return container_of(inode, struct ext4_inode_info, vfs_inode);
1685 }
1686
1687 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1688 {
1689         return ino == EXT4_ROOT_INO ||
1690                 (ino >= EXT4_FIRST_INO(sb) &&
1691                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1692 }
1693
1694 /*
1695  * Returns: sbi->field[index]
1696  * Used to access an array element from the following sbi fields which require
1697  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1698  * - s_group_desc
1699  * - s_group_info
1700  * - s_flex_group
1701  */
1702 #define sbi_array_rcu_deref(sbi, field, index)                             \
1703 ({                                                                         \
1704         typeof(*((sbi)->field)) _v;                                        \
1705         rcu_read_lock();                                                   \
1706         _v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];          \
1707         rcu_read_unlock();                                                 \
1708         _v;                                                                \
1709 })
1710
1711 /*
1712  * run-time mount flags
1713  */
1714 enum {
1715         EXT4_MF_MNTDIR_SAMPLED,
1716         EXT4_MF_FS_ABORTED,     /* Fatal error detected */
1717         EXT4_MF_FC_INELIGIBLE   /* Fast commit ineligible */
1718 };
1719
1720 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
1721 {
1722         set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1723 }
1724
1725 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
1726 {
1727         clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1728 }
1729
1730 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
1731 {
1732         return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1733 }
1734
1735
1736 /*
1737  * Simulate_fail codes
1738  */
1739 #define EXT4_SIM_BBITMAP_EIO    1
1740 #define EXT4_SIM_BBITMAP_CRC    2
1741 #define EXT4_SIM_IBITMAP_EIO    3
1742 #define EXT4_SIM_IBITMAP_CRC    4
1743 #define EXT4_SIM_INODE_EIO      5
1744 #define EXT4_SIM_INODE_CRC      6
1745 #define EXT4_SIM_DIRBLOCK_EIO   7
1746 #define EXT4_SIM_DIRBLOCK_CRC   8
1747
1748 static inline bool ext4_simulate_fail(struct super_block *sb,
1749                                      unsigned long code)
1750 {
1751 #ifdef CONFIG_EXT4_DEBUG
1752         struct ext4_sb_info *sbi = EXT4_SB(sb);
1753
1754         if (unlikely(sbi->s_simulate_fail == code)) {
1755                 sbi->s_simulate_fail = 0;
1756                 return true;
1757         }
1758 #endif
1759         return false;
1760 }
1761
1762 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1763                                          struct buffer_head *bh,
1764                                          unsigned long code)
1765 {
1766         if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1767                 clear_buffer_uptodate(bh);
1768 }
1769
1770 /*
1771  * Error number codes for s_{first,last}_error_errno
1772  *
1773  * Linux errno numbers are architecture specific, so we need to translate
1774  * them into something which is architecture independent.   We don't define
1775  * codes for all errno's; just the ones which are most likely to be the cause
1776  * of an ext4_error() call.
1777  */
1778 #define EXT4_ERR_UNKNOWN         1
1779 #define EXT4_ERR_EIO             2
1780 #define EXT4_ERR_ENOMEM          3
1781 #define EXT4_ERR_EFSBADCRC       4
1782 #define EXT4_ERR_EFSCORRUPTED    5
1783 #define EXT4_ERR_ENOSPC          6
1784 #define EXT4_ERR_ENOKEY          7
1785 #define EXT4_ERR_EROFS           8
1786 #define EXT4_ERR_EFBIG           9
1787 #define EXT4_ERR_EEXIST         10
1788 #define EXT4_ERR_ERANGE         11
1789 #define EXT4_ERR_EOVERFLOW      12
1790 #define EXT4_ERR_EBUSY          13
1791 #define EXT4_ERR_ENOTDIR        14
1792 #define EXT4_ERR_ENOTEMPTY      15
1793 #define EXT4_ERR_ESHUTDOWN      16
1794 #define EXT4_ERR_EFAULT         17
1795
1796 /*
1797  * Inode dynamic state flags
1798  */
1799 enum {
1800         EXT4_STATE_NEW,                 /* inode is newly created */
1801         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1802         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1803         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1804         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1805         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1806         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1807         EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
1808         EXT4_STATE_LUSTRE_EA_INODE,     /* Lustre-style ea_inode */
1809         EXT4_STATE_VERITY_IN_PROGRESS,  /* building fs-verity Merkle tree */
1810         EXT4_STATE_FC_COMMITTING,       /* Fast commit ongoing */
1811         EXT4_STATE_ORPHAN_FILE,         /* Inode orphaned in orphan file */
1812 };
1813
1814 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1815 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1816 {                                                                       \
1817         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1818 }                                                                       \
1819 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1820 {                                                                       \
1821         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1822 }                                                                       \
1823 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1824 {                                                                       \
1825         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1826 }
1827
1828 /* Add these declarations here only so that these functions can be
1829  * found by name.  Otherwise, they are very hard to locate. */
1830 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1831 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1832 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1833 EXT4_INODE_BIT_FNS(flag, flags, 0)
1834
1835 /* Add these declarations here only so that these functions can be
1836  * found by name.  Otherwise, they are very hard to locate. */
1837 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1838 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1839 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1840 #if (BITS_PER_LONG < 64)
1841 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1842
1843 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1844 {
1845         (ei)->i_state_flags = 0;
1846 }
1847 #else
1848 EXT4_INODE_BIT_FNS(state, flags, 32)
1849
1850 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1851 {
1852         /* We depend on the fact that callers will set i_flags */
1853 }
1854 #endif
1855 #else
1856 /* Assume that user mode programs are passing in an ext4fs superblock, not
1857  * a kernel struct super_block.  This will allow us to call the feature-test
1858  * macros from user land. */
1859 #define EXT4_SB(sb)     (sb)
1860 #endif
1861
1862 static inline bool ext4_verity_in_progress(struct inode *inode)
1863 {
1864         return IS_ENABLED(CONFIG_FS_VERITY) &&
1865                ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1866 }
1867
1868 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1869
1870 /*
1871  * Codes for operating systems
1872  */
1873 #define EXT4_OS_LINUX           0
1874 #define EXT4_OS_HURD            1
1875 #define EXT4_OS_MASIX           2
1876 #define EXT4_OS_FREEBSD         3
1877 #define EXT4_OS_LITES           4
1878
1879 /*
1880  * Revision levels
1881  */
1882 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1883 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1884
1885 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1886
1887 #define EXT4_GOOD_OLD_INODE_SIZE 128
1888
1889 #define EXT4_EXTRA_TIMESTAMP_MAX        (((s64)1 << 34) - 1  + S32_MIN)
1890 #define EXT4_NON_EXTRA_TIMESTAMP_MAX    S32_MAX
1891 #define EXT4_TIMESTAMP_MIN              S32_MIN
1892
1893 /*
1894  * Feature set definitions
1895  */
1896
1897 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1898 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1899 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1900 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1901 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1902 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1903 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2       0x0200
1904 /*
1905  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
1906  * incompatible only if fast commit blocks are present in the FS. Since we
1907  * clear the journal (and thus the fast commit blocks), we don't mark FS as
1908  * incompatible. We also have a JBD2 incompat feature, which gets set when
1909  * there are fast commit blocks present in the journal.
1910  */
1911 #define EXT4_FEATURE_COMPAT_FAST_COMMIT         0x0400
1912 #define EXT4_FEATURE_COMPAT_STABLE_INODES       0x0800
1913 #define EXT4_FEATURE_COMPAT_ORPHAN_FILE         0x1000  /* Orphan file exists */
1914
1915 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1916 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1917 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1918 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1919 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1920 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1921 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1922 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1923 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1924 /*
1925  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1926  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1927  * all other data structures' checksums.  However, the METADATA_CSUM and
1928  * GDT_CSUM bits are mutually exclusive.
1929  */
1930 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1931 #define EXT4_FEATURE_RO_COMPAT_READONLY         0x1000
1932 #define EXT4_FEATURE_RO_COMPAT_PROJECT          0x2000
1933 #define EXT4_FEATURE_RO_COMPAT_VERITY           0x8000
1934 #define EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT   0x10000 /* Orphan file may be
1935                                                            non-empty */
1936
1937 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1938 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1939 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1940 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1941 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1942 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1943 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1944 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1945 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1946 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1947 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1948 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED         0x2000
1949 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1950 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1951 #define EXT4_FEATURE_INCOMPAT_ENCRYPT           0x10000
1952 #define EXT4_FEATURE_INCOMPAT_CASEFOLD          0x20000
1953
1954 extern void ext4_update_dynamic_rev(struct super_block *sb);
1955
1956 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1957 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1958 { \
1959         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1960                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1961 } \
1962 static inline void ext4_set_feature_##name(struct super_block *sb) \
1963 { \
1964         ext4_update_dynamic_rev(sb); \
1965         EXT4_SB(sb)->s_es->s_feature_compat |= \
1966                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1967 } \
1968 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1969 { \
1970         EXT4_SB(sb)->s_es->s_feature_compat &= \
1971                 ~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1972 }
1973
1974 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1975 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1976 { \
1977         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1978                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1979 } \
1980 static inline void ext4_set_feature_##name(struct super_block *sb) \
1981 { \
1982         ext4_update_dynamic_rev(sb); \
1983         EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1984                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1985 } \
1986 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1987 { \
1988         EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1989                 ~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1990 }
1991
1992 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1993 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1994 { \
1995         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1996                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1997 } \
1998 static inline void ext4_set_feature_##name(struct super_block *sb) \
1999 { \
2000         ext4_update_dynamic_rev(sb); \
2001         EXT4_SB(sb)->s_es->s_feature_incompat |= \
2002                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2003 } \
2004 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2005 { \
2006         EXT4_SB(sb)->s_es->s_feature_incompat &= \
2007                 ~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2008 }
2009
2010 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,         DIR_PREALLOC)
2011 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,        IMAGIC_INODES)
2012 EXT4_FEATURE_COMPAT_FUNCS(journal,              HAS_JOURNAL)
2013 EXT4_FEATURE_COMPAT_FUNCS(xattr,                EXT_ATTR)
2014 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,         RESIZE_INODE)
2015 EXT4_FEATURE_COMPAT_FUNCS(dir_index,            DIR_INDEX)
2016 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,        SPARSE_SUPER2)
2017 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,          FAST_COMMIT)
2018 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,        STABLE_INODES)
2019 EXT4_FEATURE_COMPAT_FUNCS(orphan_file,          ORPHAN_FILE)
2020
2021 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,      SPARSE_SUPER)
2022 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,        LARGE_FILE)
2023 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,         BTREE_DIR)
2024 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,         HUGE_FILE)
2025 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,          GDT_CSUM)
2026 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,         DIR_NLINK)
2027 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,       EXTRA_ISIZE)
2028 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,             QUOTA)
2029 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,          BIGALLOC)
2030 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,     METADATA_CSUM)
2031 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,          READONLY)
2032 EXT4_FEATURE_RO_COMPAT_FUNCS(project,           PROJECT)
2033 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,            VERITY)
2034 EXT4_FEATURE_RO_COMPAT_FUNCS(orphan_present,    ORPHAN_PRESENT)
2035
2036 EXT4_FEATURE_INCOMPAT_FUNCS(compression,        COMPRESSION)
2037 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,           FILETYPE)
2038 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,     RECOVER)
2039 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,        JOURNAL_DEV)
2040 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,            META_BG)
2041 EXT4_FEATURE_INCOMPAT_FUNCS(extents,            EXTENTS)
2042 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,              64BIT)
2043 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,                MMP)
2044 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,            FLEX_BG)
2045 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,           EA_INODE)
2046 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,            DIRDATA)
2047 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,          CSUM_SEED)
2048 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,           LARGEDIR)
2049 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,        INLINE_DATA)
2050 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,            ENCRYPT)
2051 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,           CASEFOLD)
2052
2053 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2054 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2055                                          EXT4_FEATURE_INCOMPAT_META_BG)
2056 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2057                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2058                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2059
2060 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2061 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2062                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
2063                                          EXT4_FEATURE_INCOMPAT_META_BG)
2064 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2065                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2066                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2067
2068 #define EXT4_FEATURE_COMPAT_SUPP        (EXT4_FEATURE_COMPAT_EXT_ATTR| \
2069                                          EXT4_FEATURE_COMPAT_ORPHAN_FILE)
2070 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2071                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
2072                                          EXT4_FEATURE_INCOMPAT_META_BG| \
2073                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
2074                                          EXT4_FEATURE_INCOMPAT_64BIT| \
2075                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2076                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
2077                                          EXT4_FEATURE_INCOMPAT_MMP | \
2078                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2079                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2080                                          EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2081                                          EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2082                                          EXT4_FEATURE_INCOMPAT_LARGEDIR)
2083 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2084                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2085                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2086                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2087                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2088                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2089                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2090                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2091                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2092                                          EXT4_FEATURE_RO_COMPAT_QUOTA |\
2093                                          EXT4_FEATURE_RO_COMPAT_PROJECT |\
2094                                          EXT4_FEATURE_RO_COMPAT_VERITY |\
2095                                          EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT)
2096
2097 #define EXTN_FEATURE_FUNCS(ver) \
2098 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2099 { \
2100         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2101                 cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2102 } \
2103 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2104 { \
2105         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2106                 cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2107 } \
2108 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2109 { \
2110         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2111                 cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2112 }
2113
2114 EXTN_FEATURE_FUNCS(2)
2115 EXTN_FEATURE_FUNCS(3)
2116 EXTN_FEATURE_FUNCS(4)
2117
2118 static inline bool ext4_has_compat_features(struct super_block *sb)
2119 {
2120         return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2121 }
2122 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2123 {
2124         return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2125 }
2126 static inline bool ext4_has_incompat_features(struct super_block *sb)
2127 {
2128         return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2129 }
2130
2131 extern int ext4_feature_set_ok(struct super_block *sb, int readonly);
2132
2133 /*
2134  * Superblock flags
2135  */
2136 #define EXT4_FLAGS_RESIZING     0
2137 #define EXT4_FLAGS_SHUTDOWN     1
2138 #define EXT4_FLAGS_BDEV_IS_DAX  2
2139
2140 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2141 {
2142         return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2143 }
2144
2145 /*
2146  * Default values for user and/or group using reserved blocks
2147  */
2148 #define EXT4_DEF_RESUID         0
2149 #define EXT4_DEF_RESGID         0
2150
2151 /*
2152  * Default project ID
2153  */
2154 #define EXT4_DEF_PROJID         0
2155
2156 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
2157
2158 /*
2159  * Default mount options
2160  */
2161 #define EXT4_DEFM_DEBUG         0x0001
2162 #define EXT4_DEFM_BSDGROUPS     0x0002
2163 #define EXT4_DEFM_XATTR_USER    0x0004
2164 #define EXT4_DEFM_ACL           0x0008
2165 #define EXT4_DEFM_UID16         0x0010
2166 #define EXT4_DEFM_JMODE         0x0060
2167 #define EXT4_DEFM_JMODE_DATA    0x0020
2168 #define EXT4_DEFM_JMODE_ORDERED 0x0040
2169 #define EXT4_DEFM_JMODE_WBACK   0x0060
2170 #define EXT4_DEFM_NOBARRIER     0x0100
2171 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2172 #define EXT4_DEFM_DISCARD       0x0400
2173 #define EXT4_DEFM_NODELALLOC    0x0800
2174
2175 /*
2176  * Default journal batch times
2177  */
2178 #define EXT4_DEF_MIN_BATCH_TIME 0
2179 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
2180
2181 /*
2182  * Minimum number of groups in a flexgroup before we separate out
2183  * directories into the first block group of a flexgroup
2184  */
2185 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
2186
2187 /*
2188  * Structure of a directory entry
2189  */
2190 #define EXT4_NAME_LEN 255
2191 /*
2192  * Base length of the ext4 directory entry excluding the name length
2193  */
2194 #define EXT4_BASE_DIR_LEN (sizeof(struct ext4_dir_entry_2) - EXT4_NAME_LEN)
2195
2196 struct ext4_dir_entry {
2197         __le32  inode;                  /* Inode number */
2198         __le16  rec_len;                /* Directory entry length */
2199         __le16  name_len;               /* Name length */
2200         char    name[EXT4_NAME_LEN];    /* File name */
2201 };
2202
2203
2204 /*
2205  * Encrypted Casefolded entries require saving the hash on disk. This structure
2206  * followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
2207  * boundary.
2208  */
2209 struct ext4_dir_entry_hash {
2210         __le32 hash;
2211         __le32 minor_hash;
2212 };
2213
2214 /*
2215  * The new version of the directory entry.  Since EXT4 structures are
2216  * stored in intel byte order, and the name_len field could never be
2217  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2218  * file_type field.
2219  */
2220 struct ext4_dir_entry_2 {
2221         __le32  inode;                  /* Inode number */
2222         __le16  rec_len;                /* Directory entry length */
2223         __u8    name_len;               /* Name length */
2224         __u8    file_type;              /* See file type macros EXT4_FT_* below */
2225         char    name[EXT4_NAME_LEN];    /* File name */
2226 };
2227
2228 /*
2229  * Access the hashes at the end of ext4_dir_entry_2
2230  */
2231 #define EXT4_DIRENT_HASHES(entry) \
2232         ((struct ext4_dir_entry_hash *) \
2233                 (((void *)(entry)) + \
2234                 ((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
2235 #define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(de)->hash)
2236 #define EXT4_DIRENT_MINOR_HASH(entry) \
2237                 le32_to_cpu(EXT4_DIRENT_HASHES(de)->minor_hash)
2238
2239 static inline bool ext4_hash_in_dirent(const struct inode *inode)
2240 {
2241         return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
2242 }
2243
2244 /*
2245  * This is a bogus directory entry at the end of each leaf block that
2246  * records checksums.
2247  */
2248 struct ext4_dir_entry_tail {
2249         __le32  det_reserved_zero1;     /* Pretend to be unused */
2250         __le16  det_rec_len;            /* 12 */
2251         __u8    det_reserved_zero2;     /* Zero name length */
2252         __u8    det_reserved_ft;        /* 0xDE, fake file type */
2253         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
2254 };
2255
2256 #define EXT4_DIRENT_TAIL(block, blocksize) \
2257         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2258                                         ((blocksize) - \
2259                                          sizeof(struct ext4_dir_entry_tail))))
2260
2261 /*
2262  * Ext4 directory file types.  Only the low 3 bits are used.  The
2263  * other bits are reserved for now.
2264  */
2265 #define EXT4_FT_UNKNOWN         0
2266 #define EXT4_FT_REG_FILE        1
2267 #define EXT4_FT_DIR             2
2268 #define EXT4_FT_CHRDEV          3
2269 #define EXT4_FT_BLKDEV          4
2270 #define EXT4_FT_FIFO            5
2271 #define EXT4_FT_SOCK            6
2272 #define EXT4_FT_SYMLINK         7
2273
2274 #define EXT4_FT_MAX             8
2275
2276 #define EXT4_FT_DIR_CSUM        0xDE
2277
2278 /*
2279  * EXT4_DIR_PAD defines the directory entries boundaries
2280  *
2281  * NOTE: It must be a multiple of 4
2282  */
2283 #define EXT4_DIR_PAD                    4
2284 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
2285 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
2286
2287 /*
2288  * The rec_len is dependent on the type of directory. Directories that are
2289  * casefolded and encrypted need to store the hash as well, so we add room for
2290  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
2291  * pass NULL for dir, as those entries do not use the extra fields.
2292  */
2293 static inline unsigned int ext4_dir_rec_len(__u8 name_len,
2294                                                 const struct inode *dir)
2295 {
2296         int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
2297
2298         if (dir && ext4_hash_in_dirent(dir))
2299                 rec_len += sizeof(struct ext4_dir_entry_hash);
2300         return (rec_len & ~EXT4_DIR_ROUND);
2301 }
2302
2303 /*
2304  * If we ever get support for fs block sizes > page_size, we'll need
2305  * to remove the #if statements in the next two functions...
2306  */
2307 static inline unsigned int
2308 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2309 {
2310         unsigned len = le16_to_cpu(dlen);
2311
2312 #if (PAGE_SIZE >= 65536)
2313         if (len == EXT4_MAX_REC_LEN || len == 0)
2314                 return blocksize;
2315         return (len & 65532) | ((len & 3) << 16);
2316 #else
2317         return len;
2318 #endif
2319 }
2320
2321 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2322 {
2323         BUG_ON((len > blocksize) || (blocksize > (1 << 18)) || (len & 3));
2324 #if (PAGE_SIZE >= 65536)
2325         if (len < 65536)
2326                 return cpu_to_le16(len);
2327         if (len == blocksize) {
2328                 if (blocksize == 65536)
2329                         return cpu_to_le16(EXT4_MAX_REC_LEN);
2330                 else
2331                         return cpu_to_le16(0);
2332         }
2333         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2334 #else
2335         return cpu_to_le16(len);
2336 #endif
2337 }
2338
2339 /*
2340  * Hash Tree Directory indexing
2341  * (c) Daniel Phillips, 2001
2342  */
2343
2344 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2345                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2346 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2347                     !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2348 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2349
2350 /* Legal values for the dx_root hash_version field: */
2351
2352 #define DX_HASH_LEGACY                  0
2353 #define DX_HASH_HALF_MD4                1
2354 #define DX_HASH_TEA                     2
2355 #define DX_HASH_LEGACY_UNSIGNED         3
2356 #define DX_HASH_HALF_MD4_UNSIGNED       4
2357 #define DX_HASH_TEA_UNSIGNED            5
2358 #define DX_HASH_SIPHASH                 6
2359
2360 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2361                               const void *address, unsigned int length)
2362 {
2363         struct {
2364                 struct shash_desc shash;
2365                 char ctx[4];
2366         } desc;
2367
2368         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2369
2370         desc.shash.tfm = sbi->s_chksum_driver;
2371         *(u32 *)desc.ctx = crc;
2372
2373         BUG_ON(crypto_shash_update(&desc.shash, address, length));
2374
2375         return *(u32 *)desc.ctx;
2376 }
2377
2378 #ifdef __KERNEL__
2379
2380 /* hash info structure used by the directory hash */
2381 struct dx_hash_info
2382 {
2383         u32             hash;
2384         u32             minor_hash;
2385         int             hash_version;
2386         u32             *seed;
2387 };
2388
2389
2390 /* 32 and 64 bit signed EOF for dx directories */
2391 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2392 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2393
2394
2395 /*
2396  * Control parameters used by ext4_htree_next_block
2397  */
2398 #define HASH_NB_ALWAYS          1
2399
2400 struct ext4_filename {
2401         const struct qstr *usr_fname;
2402         struct fscrypt_str disk_name;
2403         struct dx_hash_info hinfo;
2404 #ifdef CONFIG_FS_ENCRYPTION
2405         struct fscrypt_str crypto_buf;
2406 #endif
2407 #if IS_ENABLED(CONFIG_UNICODE)
2408         struct fscrypt_str cf_name;
2409 #endif
2410 };
2411
2412 #define fname_name(p) ((p)->disk_name.name)
2413 #define fname_usr_name(p) ((p)->usr_fname->name)
2414 #define fname_len(p)  ((p)->disk_name.len)
2415
2416 /*
2417  * Describe an inode's exact location on disk and in memory
2418  */
2419 struct ext4_iloc
2420 {
2421         struct buffer_head *bh;
2422         unsigned long offset;
2423         ext4_group_t block_group;
2424 };
2425
2426 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2427 {
2428         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2429 }
2430
2431 static inline bool ext4_is_quota_file(struct inode *inode)
2432 {
2433         return IS_NOQUOTA(inode) &&
2434                !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2435 }
2436
2437 /*
2438  * This structure is stuffed into the struct file's private_data field
2439  * for directories.  It is where we put information so that we can do
2440  * readdir operations in hash tree order.
2441  */
2442 struct dir_private_info {
2443         struct rb_root  root;
2444         struct rb_node  *curr_node;
2445         struct fname    *extra_fname;
2446         loff_t          last_pos;
2447         __u32           curr_hash;
2448         __u32           curr_minor_hash;
2449         __u32           next_hash;
2450 };
2451
2452 /* calculate the first block number of the group */
2453 static inline ext4_fsblk_t
2454 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2455 {
2456         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2457                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2458 }
2459
2460 /*
2461  * Special error return code only used by dx_probe() and its callers.
2462  */
2463 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
2464
2465 /* htree levels for ext4 */
2466 #define EXT4_HTREE_LEVEL_COMPAT 2
2467 #define EXT4_HTREE_LEVEL        3
2468
2469 static inline int ext4_dir_htree_level(struct super_block *sb)
2470 {
2471         return ext4_has_feature_largedir(sb) ?
2472                 EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2473 }
2474
2475 /*
2476  * Timeout and state flag for lazy initialization inode thread.
2477  */
2478 #define EXT4_DEF_LI_WAIT_MULT                   10
2479 #define EXT4_DEF_LI_MAX_START_DELAY             5
2480 #define EXT4_LAZYINIT_QUIT                      0x0001
2481 #define EXT4_LAZYINIT_RUNNING                   0x0002
2482
2483 /*
2484  * Lazy inode table initialization info
2485  */
2486 struct ext4_lazy_init {
2487         unsigned long           li_state;
2488         struct list_head        li_request_list;
2489         struct mutex            li_list_mtx;
2490 };
2491
2492 enum ext4_li_mode {
2493         EXT4_LI_MODE_PREFETCH_BBITMAP,
2494         EXT4_LI_MODE_ITABLE,
2495 };
2496
2497 struct ext4_li_request {
2498         struct super_block      *lr_super;
2499         enum ext4_li_mode       lr_mode;
2500         ext4_group_t            lr_first_not_zeroed;
2501         ext4_group_t            lr_next_group;
2502         struct list_head        lr_request;
2503         unsigned long           lr_next_sched;
2504         unsigned long           lr_timeout;
2505 };
2506
2507 struct ext4_features {
2508         struct kobject f_kobj;
2509         struct completion f_kobj_unregister;
2510 };
2511
2512 /*
2513  * This structure will be used for multiple mount protection. It will be
2514  * written into the block number saved in the s_mmp_block field in the
2515  * superblock. Programs that check MMP should assume that if
2516  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2517  * to use the filesystem, regardless of how old the timestamp is.
2518  */
2519 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2520 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2521 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2522 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2523
2524 struct mmp_struct {
2525         __le32  mmp_magic;              /* Magic number for MMP */
2526         __le32  mmp_seq;                /* Sequence no. updated periodically */
2527
2528         /*
2529          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2530          * purposes and do not affect the correctness of the algorithm
2531          */
2532         __le64  mmp_time;               /* Time last updated */
2533         char    mmp_nodename[64];       /* Node which last updated MMP block */
2534         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
2535
2536         /*
2537          * mmp_check_interval is used to verify if the MMP block has been
2538          * updated on the block device. The value is updated based on the
2539          * maximum time to write the MMP block during an update cycle.
2540          */
2541         __le16  mmp_check_interval;
2542
2543         __le16  mmp_pad1;
2544         __le32  mmp_pad2[226];
2545         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
2546 };
2547
2548 /* arguments passed to the mmp thread */
2549 struct mmpd_data {
2550         struct buffer_head *bh; /* bh from initial read_mmp_block() */
2551         struct super_block *sb;  /* super block of the fs */
2552 };
2553
2554 /*
2555  * Check interval multiplier
2556  * The MMP block is written every update interval and initially checked every
2557  * update interval x the multiplier (the value is then adapted based on the
2558  * write latency). The reason is that writes can be delayed under load and we
2559  * don't want readers to incorrectly assume that the filesystem is no longer
2560  * in use.
2561  */
2562 #define EXT4_MMP_CHECK_MULT             2UL
2563
2564 /*
2565  * Minimum interval for MMP checking in seconds.
2566  */
2567 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
2568
2569 /*
2570  * Maximum interval for MMP checking in seconds.
2571  */
2572 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
2573
2574 /*
2575  * Function prototypes
2576  */
2577
2578 /*
2579  * Ok, these declarations are also in <linux/kernel.h> but none of the
2580  * ext4 source programs needs to include it so they are duplicated here.
2581  */
2582 # define NORET_TYPE     /**/
2583 # define ATTRIB_NORET   __attribute__((noreturn))
2584 # define NORET_AND      noreturn,
2585
2586 /* bitmap.c */
2587 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2588 void ext4_inode_bitmap_csum_set(struct super_block *sb,
2589                                 struct ext4_group_desc *gdp,
2590                                 struct buffer_head *bh, int sz);
2591 int ext4_inode_bitmap_csum_verify(struct super_block *sb,
2592                                   struct ext4_group_desc *gdp,
2593                                   struct buffer_head *bh, int sz);
2594 void ext4_block_bitmap_csum_set(struct super_block *sb,
2595                                 struct ext4_group_desc *gdp,
2596                                 struct buffer_head *bh);
2597 int ext4_block_bitmap_csum_verify(struct super_block *sb,
2598                                   struct ext4_group_desc *gdp,
2599                                   struct buffer_head *bh);
2600
2601 /* balloc.c */
2602 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2603                                          ext4_fsblk_t blocknr,
2604                                          ext4_group_t *blockgrpp,
2605                                          ext4_grpblk_t *offsetp);
2606 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2607                                           ext4_fsblk_t block);
2608
2609 extern unsigned int ext4_block_group(struct super_block *sb,
2610                         ext4_fsblk_t blocknr);
2611 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2612                         ext4_fsblk_t blocknr);
2613 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2614 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2615                         ext4_group_t group);
2616 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2617                                          ext4_fsblk_t goal,
2618                                          unsigned int flags,
2619                                          unsigned long *count,
2620                                          int *errp);
2621 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2622                                     s64 nclusters, unsigned int flags);
2623 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2624 extern void ext4_check_blocks_bitmap(struct super_block *);
2625 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2626                                                     ext4_group_t block_group,
2627                                                     struct buffer_head ** bh);
2628 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2629
2630 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2631                                                 ext4_group_t block_group,
2632                                                 bool ignore_locked);
2633 extern int ext4_wait_block_bitmap(struct super_block *sb,
2634                                   ext4_group_t block_group,
2635                                   struct buffer_head *bh);
2636 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2637                                                   ext4_group_t block_group);
2638 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2639                                               ext4_group_t block_group,
2640                                               struct ext4_group_desc *gdp);
2641 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2642
2643 #if IS_ENABLED(CONFIG_UNICODE)
2644 extern int ext4_fname_setup_ci_filename(struct inode *dir,
2645                                          const struct qstr *iname,
2646                                          struct ext4_filename *fname);
2647 #endif
2648
2649 /* ext4 encryption related stuff goes here crypto.c */
2650 #ifdef CONFIG_FS_ENCRYPTION
2651 extern const struct fscrypt_operations ext4_cryptops;
2652
2653 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
2654                               int lookup, struct ext4_filename *fname);
2655
2656 int ext4_fname_prepare_lookup(struct inode *dir, struct dentry *dentry,
2657                               struct ext4_filename *fname);
2658
2659 void ext4_fname_free_filename(struct ext4_filename *fname);
2660
2661 int ext4_ioctl_get_encryption_pwsalt(struct file *filp, void __user *arg);
2662
2663 #else /* !CONFIG_FS_ENCRYPTION */
2664 static inline int ext4_fname_setup_filename(struct inode *dir,
2665                                             const struct qstr *iname,
2666                                             int lookup,
2667                                             struct ext4_filename *fname)
2668 {
2669         int err = 0;
2670         fname->usr_fname = iname;
2671         fname->disk_name.name = (unsigned char *) iname->name;
2672         fname->disk_name.len = iname->len;
2673
2674 #if IS_ENABLED(CONFIG_UNICODE)
2675         err = ext4_fname_setup_ci_filename(dir, iname, fname);
2676 #endif
2677
2678         return err;
2679 }
2680
2681 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2682                                             struct dentry *dentry,
2683                                             struct ext4_filename *fname)
2684 {
2685         return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2686 }
2687
2688 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2689 {
2690 #if IS_ENABLED(CONFIG_UNICODE)
2691         kfree(fname->cf_name.name);
2692         fname->cf_name.name = NULL;
2693 #endif
2694 }
2695
2696 static inline int ext4_ioctl_get_encryption_pwsalt(struct file *filp,
2697                                                    void __user *arg)
2698 {
2699         return -EOPNOTSUPP;
2700 }
2701 #endif /* !CONFIG_FS_ENCRYPTION */
2702
2703 /* dir.c */
2704 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2705                                   struct file *,
2706                                   struct ext4_dir_entry_2 *,
2707                                   struct buffer_head *, char *, int,
2708                                   unsigned int);
2709 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
2710         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2711                                 (de), (bh), (buf), (size), (offset)))
2712 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2713                                 __u32 minor_hash,
2714                                 struct ext4_dir_entry_2 *dirent,
2715                                 struct fscrypt_str *ent_name);
2716 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2717 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2718                              struct buffer_head *bh,
2719                              void *buf, int buf_size,
2720                              struct ext4_filename *fname,
2721                              struct ext4_dir_entry_2 **dest_de);
2722 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
2723                         struct ext4_dir_entry_2 *de,
2724                         int buf_size,
2725                         struct ext4_filename *fname);
2726 static inline void ext4_update_dx_flag(struct inode *inode)
2727 {
2728         if (!ext4_has_feature_dir_index(inode->i_sb) &&
2729             ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
2730                 /* ext4_iget() should have caught this... */
2731                 WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2732                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2733         }
2734 }
2735 static const unsigned char ext4_filetype_table[] = {
2736         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2737 };
2738
2739 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2740 {
2741         if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2742                 return DT_UNKNOWN;
2743
2744         return ext4_filetype_table[filetype];
2745 }
2746 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2747                              void *buf, int buf_size);
2748
2749 /* fsync.c */
2750 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2751
2752 /* hash.c */
2753 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2754                           struct dx_hash_info *hinfo);
2755
2756 /* ialloc.c */
2757 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2758 extern struct inode *__ext4_new_inode(struct mnt_idmap *, handle_t *,
2759                                       struct inode *, umode_t,
2760                                       const struct qstr *qstr, __u32 goal,
2761                                       uid_t *owner, __u32 i_flags,
2762                                       int handle_type, unsigned int line_no,
2763                                       int nblocks);
2764
2765 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
2766         __ext4_new_inode(&nop_mnt_idmap, (handle), (dir), (mode), (qstr),      \
2767                          (goal), (owner), i_flags, 0, 0, 0)
2768 #define ext4_new_inode_start_handle(idmap, dir, mode, qstr, goal, owner, \
2769                                     type, nblocks)                  \
2770         __ext4_new_inode((idmap), NULL, (dir), (mode), (qstr), (goal), (owner), \
2771                          0, (type), __LINE__, (nblocks))
2772
2773
2774 extern void ext4_free_inode(handle_t *, struct inode *);
2775 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2776 extern unsigned long ext4_count_free_inodes(struct super_block *);
2777 extern unsigned long ext4_count_dirs(struct super_block *);
2778 extern void ext4_check_inodes_bitmap(struct super_block *);
2779 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2780 extern int ext4_init_inode_table(struct super_block *sb,
2781                                  ext4_group_t group, int barrier);
2782 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2783
2784 /* fast_commit.c */
2785 int ext4_fc_info_show(struct seq_file *seq, void *v);
2786 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2787 void ext4_fc_init_inode(struct inode *inode);
2788 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
2789                          ext4_lblk_t end);
2790 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
2791         struct dentry *dentry);
2792 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
2793         struct dentry *dentry);
2794 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
2795 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
2796 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
2797                             struct dentry *dentry);
2798 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
2799 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
2800 void ext4_fc_mark_ineligible(struct super_block *sb, int reason, handle_t *handle);
2801 void ext4_fc_start_update(struct inode *inode);
2802 void ext4_fc_stop_update(struct inode *inode);
2803 void ext4_fc_del(struct inode *inode);
2804 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2805 void ext4_fc_replay_cleanup(struct super_block *sb);
2806 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2807 int __init ext4_fc_init_dentry_cache(void);
2808 void ext4_fc_destroy_dentry_cache(void);
2809 int ext4_fc_record_regions(struct super_block *sb, int ino,
2810                            ext4_lblk_t lblk, ext4_fsblk_t pblk,
2811                            int len, int replay);
2812
2813 /* mballoc.c */
2814 extern const struct seq_operations ext4_mb_seq_groups_ops;
2815 extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
2816 extern long ext4_mb_stats;
2817 extern long ext4_mb_max_to_scan;
2818 extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset);
2819 extern int ext4_mb_init(struct super_block *);
2820 extern int ext4_mb_release(struct super_block *);
2821 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2822                                 struct ext4_allocation_request *, int *);
2823 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2824 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2825 extern int __init ext4_init_mballoc(void);
2826 extern void ext4_exit_mballoc(void);
2827 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2828                                      ext4_group_t group,
2829                                      unsigned int nr, int *cnt);
2830 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2831                                   unsigned int nr);
2832
2833 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2834                              struct buffer_head *bh, ext4_fsblk_t block,
2835                              unsigned long count, int flags);
2836 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2837                                    ext4_group_t ngroups);
2838 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2839                 ext4_group_t i, struct ext4_group_desc *desc);
2840 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2841                                 ext4_fsblk_t block, unsigned long count);
2842 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2843 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2844 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2845                        int len, int state);
2846
2847 /* inode.c */
2848 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2849                          struct ext4_inode_info *ei);
2850 int ext4_inode_is_fast_symlink(struct inode *inode);
2851 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2852 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2853 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2854                      bool wait, struct buffer_head **bhs);
2855 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2856                              struct buffer_head *bh_result, int create);
2857 int ext4_get_block(struct inode *inode, sector_t iblock,
2858                    struct buffer_head *bh_result, int create);
2859 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2860                            struct buffer_head *bh, int create);
2861 int ext4_walk_page_buffers(handle_t *handle,
2862                            struct inode *inode,
2863                            struct buffer_head *head,
2864                            unsigned from,
2865                            unsigned to,
2866                            int *partial,
2867                            int (*fn)(handle_t *handle, struct inode *inode,
2868                                      struct buffer_head *bh));
2869 int do_journal_get_write_access(handle_t *handle, struct inode *inode,
2870                                 struct buffer_head *bh);
2871 #define FALL_BACK_TO_NONDELALLOC 1
2872 #define CONVERT_INLINE_DATA      2
2873
2874 typedef enum {
2875         EXT4_IGET_NORMAL =      0,
2876         EXT4_IGET_SPECIAL =     0x0001, /* OK to iget a system inode */
2877         EXT4_IGET_HANDLE =      0x0002, /* Inode # is from a handle */
2878         EXT4_IGET_BAD =         0x0004  /* Allow to iget a bad inode */
2879 } ext4_iget_flags;
2880
2881 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2882                                  ext4_iget_flags flags, const char *function,
2883                                  unsigned int line);
2884
2885 #define ext4_iget(sb, ino, flags) \
2886         __ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2887
2888 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2889 extern int  ext4_setattr(struct mnt_idmap *, struct dentry *,
2890                          struct iattr *);
2891 extern u32  ext4_dio_alignment(struct inode *inode);
2892 extern int  ext4_getattr(struct mnt_idmap *, const struct path *,
2893                          struct kstat *, u32, unsigned int);
2894 extern void ext4_evict_inode(struct inode *);
2895 extern void ext4_clear_inode(struct inode *);
2896 extern int  ext4_file_getattr(struct mnt_idmap *, const struct path *,
2897                               struct kstat *, u32, unsigned int);
2898 extern int  ext4_sync_inode(handle_t *, struct inode *);
2899 extern void ext4_dirty_inode(struct inode *, int);
2900 extern int ext4_change_inode_journal_flag(struct inode *, int);
2901 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2902 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2903                           struct ext4_iloc *iloc);
2904 extern int ext4_inode_attach_jinode(struct inode *inode);
2905 extern int ext4_can_truncate(struct inode *inode);
2906 extern int ext4_truncate(struct inode *);
2907 extern int ext4_break_layouts(struct inode *);
2908 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2909 extern void ext4_set_inode_flags(struct inode *, bool init);
2910 extern int ext4_alloc_da_blocks(struct inode *inode);
2911 extern void ext4_set_aops(struct inode *inode);
2912 extern int ext4_writepage_trans_blocks(struct inode *);
2913 extern int ext4_normal_submit_inode_data_buffers(struct jbd2_inode *jinode);
2914 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2915 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2916                              loff_t lstart, loff_t lend);
2917 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2918 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2919 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2920 extern void ext4_da_release_space(struct inode *inode, int to_free);
2921 extern void ext4_da_update_reserve_space(struct inode *inode,
2922                                         int used, int quota_claim);
2923 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2924                               ext4_fsblk_t pblk, ext4_lblk_t len);
2925
2926 /* indirect.c */
2927 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2928                                 struct ext4_map_blocks *map, int flags);
2929 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2930 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2931 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2932                                  ext4_lblk_t start, ext4_lblk_t end);
2933
2934 /* ioctl.c */
2935 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2936 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2937 int ext4_fileattr_set(struct mnt_idmap *idmap,
2938                       struct dentry *dentry, struct fileattr *fa);
2939 int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa);
2940 extern void ext4_reset_inode_seed(struct inode *inode);
2941 int ext4_update_overhead(struct super_block *sb, bool force);
2942
2943 /* migrate.c */
2944 extern int ext4_ext_migrate(struct inode *);
2945 extern int ext4_ind_migrate(struct inode *inode);
2946
2947 /* namei.c */
2948 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2949                              struct inode *inode);
2950 extern int ext4_dirblock_csum_verify(struct inode *inode,
2951                                      struct buffer_head *bh);
2952 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2953                                 __u32 start_minor_hash, __u32 *next_hash);
2954 extern int ext4_search_dir(struct buffer_head *bh,
2955                            char *search_buf,
2956                            int buf_size,
2957                            struct inode *dir,
2958                            struct ext4_filename *fname,
2959                            unsigned int offset,
2960                            struct ext4_dir_entry_2 **res_dir);
2961 extern int ext4_generic_delete_entry(struct inode *dir,
2962                                      struct ext4_dir_entry_2 *de_del,
2963                                      struct buffer_head *bh,
2964                                      void *entry_buf,
2965                                      int buf_size,
2966                                      int csum_size);
2967 extern bool ext4_empty_dir(struct inode *inode);
2968
2969 /* resize.c */
2970 extern void ext4_kvfree_array_rcu(void *to_free);
2971 extern int ext4_group_add(struct super_block *sb,
2972                                 struct ext4_new_group_data *input);
2973 extern int ext4_group_extend(struct super_block *sb,
2974                                 struct ext4_super_block *es,
2975                                 ext4_fsblk_t n_blocks_count);
2976 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2977 extern unsigned int ext4_list_backups(struct super_block *sb,
2978                                       unsigned int *three, unsigned int *five,
2979                                       unsigned int *seven);
2980
2981 /* super.c */
2982 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2983                                          sector_t block, blk_opf_t op_flags);
2984 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
2985                                                    sector_t block);
2986 extern void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
2987                                 bh_end_io_t *end_io);
2988 extern int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
2989                         bh_end_io_t *end_io);
2990 extern int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait);
2991 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
2992 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2993 extern int ext4_calculate_overhead(struct super_block *sb);
2994 extern __le32 ext4_superblock_csum(struct super_block *sb,
2995                                    struct ext4_super_block *es);
2996 extern void ext4_superblock_csum_set(struct super_block *sb);
2997 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2998                                     ext4_group_t ngroup);
2999 extern const char *ext4_decode_error(struct super_block *sb, int errno,
3000                                      char nbuf[16]);
3001 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
3002                                              ext4_group_t block_group,
3003                                              unsigned int flags);
3004
3005 extern __printf(7, 8)
3006 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
3007                   int, __u64, const char *, ...);
3008 extern __printf(6, 7)
3009 void __ext4_error_inode(struct inode *, const char *, unsigned int,
3010                         ext4_fsblk_t, int, const char *, ...);
3011 extern __printf(5, 6)
3012 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
3013                      const char *, ...);
3014 extern void __ext4_std_error(struct super_block *, const char *,
3015                              unsigned int, int);
3016 extern __printf(4, 5)
3017 void __ext4_warning(struct super_block *, const char *, unsigned int,
3018                     const char *, ...);
3019 extern __printf(4, 5)
3020 void __ext4_warning_inode(const struct inode *inode, const char *function,
3021                           unsigned int line, const char *fmt, ...);
3022 extern __printf(3, 4)
3023 void __ext4_msg(struct super_block *, const char *, const char *, ...);
3024 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
3025                            const char *, unsigned int, const char *);
3026 extern __printf(7, 8)
3027 void __ext4_grp_locked_error(const char *, unsigned int,
3028                              struct super_block *, ext4_group_t,
3029                              unsigned long, ext4_fsblk_t,
3030                              const char *, ...);
3031
3032 #define EXT4_ERROR_INODE(inode, fmt, a...) \
3033         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3034
3035 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)                     \
3036         __ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3037
3038 #define ext4_error_inode_block(inode, block, err, fmt, a...)            \
3039         __ext4_error_inode((inode), __func__, __LINE__, (block), (err), \
3040                            (fmt), ## a)
3041
3042 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
3043         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3044
3045 #define ext4_abort(sb, err, fmt, a...)                                  \
3046         __ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3047
3048 #ifdef CONFIG_PRINTK
3049
3050 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
3051         __ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3052 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
3053         __ext4_error_inode((inode), (func), (line), (block),            \
3054                            (err), (fmt), ##__VA_ARGS__)
3055 #define ext4_error_file(file, func, line, block, fmt, ...)              \
3056         __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3057 #define ext4_error(sb, fmt, ...)                                        \
3058         __ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),      \
3059                 ##__VA_ARGS__)
3060 #define ext4_error_err(sb, err, fmt, ...)                               \
3061         __ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),  \
3062                 ##__VA_ARGS__)
3063 #define ext4_warning(sb, fmt, ...)                                      \
3064         __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3065 #define ext4_warning_inode(inode, fmt, ...)                             \
3066         __ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3067 #define ext4_msg(sb, level, fmt, ...)                           \
3068         __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3069 #define dump_mmp_msg(sb, mmp, msg)                                      \
3070         __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3071 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
3072         __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3073                                 fmt, ##__VA_ARGS__)
3074
3075 #else
3076
3077 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
3078 do {                                                                    \
3079         no_printk(fmt, ##__VA_ARGS__);                                  \
3080         __ext4_error_inode(inode, "", 0, block, 0, " ");                \
3081 } while (0)
3082 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
3083 do {                                                                    \
3084         no_printk(fmt, ##__VA_ARGS__);                                  \
3085         __ext4_error_inode(inode, "", 0, block, err, " ");              \
3086 } while (0)
3087 #define ext4_error_file(file, func, line, block, fmt, ...)              \
3088 do {                                                                    \
3089         no_printk(fmt, ##__VA_ARGS__);                                  \
3090         __ext4_error_file(file, "", 0, block, " ");                     \
3091 } while (0)
3092 #define ext4_error(sb, fmt, ...)                                        \
3093 do {                                                                    \
3094         no_printk(fmt, ##__VA_ARGS__);                                  \
3095         __ext4_error(sb, "", 0, false, 0, 0, " ");                      \
3096 } while (0)
3097 #define ext4_error_err(sb, err, fmt, ...)                               \
3098 do {                                                                    \
3099         no_printk(fmt, ##__VA_ARGS__);                                  \
3100         __ext4_error(sb, "", 0, false, err, 0, " ");                    \
3101 } while (0)
3102 #define ext4_warning(sb, fmt, ...)                                      \
3103 do {                                                                    \
3104         no_printk(fmt, ##__VA_ARGS__);                                  \
3105         __ext4_warning(sb, "", 0, " ");                                 \
3106 } while (0)
3107 #define ext4_warning_inode(inode, fmt, ...)                             \
3108 do {                                                                    \
3109         no_printk(fmt, ##__VA_ARGS__);                                  \
3110         __ext4_warning_inode(inode, "", 0, " ");                        \
3111 } while (0)
3112 #define ext4_msg(sb, level, fmt, ...)                                   \
3113 do {                                                                    \
3114         no_printk(fmt, ##__VA_ARGS__);                                  \
3115         __ext4_msg(sb, "", " ");                                        \
3116 } while (0)
3117 #define dump_mmp_msg(sb, mmp, msg)                                      \
3118         __dump_mmp_msg(sb, mmp, "", 0, "")
3119 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
3120 do {                                                                    \
3121         no_printk(fmt, ##__VA_ARGS__);                          \
3122         __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");       \
3123 } while (0)
3124
3125 #endif
3126
3127 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3128                                       struct ext4_group_desc *bg);
3129 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3130                                       struct ext4_group_desc *bg);
3131 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3132                                      struct ext4_group_desc *bg);
3133 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3134                                       struct ext4_group_desc *bg);
3135 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3136                                  struct ext4_group_desc *bg);
3137 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3138                                 struct ext4_group_desc *bg);
3139 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3140                                    struct ext4_group_desc *bg);
3141 extern void ext4_block_bitmap_set(struct super_block *sb,
3142                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
3143 extern void ext4_inode_bitmap_set(struct super_block *sb,
3144                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
3145 extern void ext4_inode_table_set(struct super_block *sb,
3146                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3147 extern void ext4_free_group_clusters_set(struct super_block *sb,
3148                                          struct ext4_group_desc *bg,
3149                                          __u32 count);
3150 extern void ext4_free_inodes_set(struct super_block *sb,
3151                                 struct ext4_group_desc *bg, __u32 count);
3152 extern void ext4_used_dirs_set(struct super_block *sb,
3153                                 struct ext4_group_desc *bg, __u32 count);
3154 extern void ext4_itable_unused_set(struct super_block *sb,
3155                                    struct ext4_group_desc *bg, __u32 count);
3156 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3157                                        struct ext4_group_desc *gdp);
3158 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3159                                      struct ext4_group_desc *gdp);
3160 extern int ext4_register_li_request(struct super_block *sb,
3161                                     ext4_group_t first_not_zeroed);
3162
3163 static inline int ext4_has_metadata_csum(struct super_block *sb)
3164 {
3165         WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3166                      !EXT4_SB(sb)->s_chksum_driver);
3167
3168         return ext4_has_feature_metadata_csum(sb) &&
3169                (EXT4_SB(sb)->s_chksum_driver != NULL);
3170 }
3171
3172 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3173 {
3174         return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3175 }
3176
3177 #define ext4_read_incompat_64bit_val(es, name) \
3178         (((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3179                 ? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3180                 le32_to_cpu(es->name##_lo))
3181
3182 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3183 {
3184         return ext4_read_incompat_64bit_val(es, s_blocks_count);
3185 }
3186
3187 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3188 {
3189         return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3190 }
3191
3192 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3193 {
3194         return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3195 }
3196
3197 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3198                                          ext4_fsblk_t blk)
3199 {
3200         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3201         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3202 }
3203
3204 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3205                                               ext4_fsblk_t blk)
3206 {
3207         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3208         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3209 }
3210
3211 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3212                                            ext4_fsblk_t blk)
3213 {
3214         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3215         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3216 }
3217
3218 static inline loff_t ext4_isize(struct super_block *sb,
3219                                 struct ext4_inode *raw_inode)
3220 {
3221         if (ext4_has_feature_largedir(sb) ||
3222             S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3223                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3224                         le32_to_cpu(raw_inode->i_size_lo);
3225
3226         return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3227 }
3228
3229 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3230 {
3231         raw_inode->i_size_lo = cpu_to_le32(i_size);
3232         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3233 }
3234
3235 static inline
3236 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3237                                             ext4_group_t group)
3238 {
3239          struct ext4_group_info **grp_info;
3240          long indexv, indexh;
3241          BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3242          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3243          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3244          grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3245          return grp_info[indexh];
3246 }
3247
3248 /*
3249  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3250  * the locking protocol documented in the comments of ext4_group_add()
3251  * in resize.c
3252  */
3253 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3254 {
3255         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
3256
3257         smp_rmb();
3258         return ngroups;
3259 }
3260
3261 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3262                                              ext4_group_t block_group)
3263 {
3264         return block_group >> sbi->s_log_groups_per_flex;
3265 }
3266
3267 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3268 {
3269         return 1 << sbi->s_log_groups_per_flex;
3270 }
3271
3272 #define ext4_std_error(sb, errno)                               \
3273 do {                                                            \
3274         if ((errno))                                            \
3275                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
3276 } while (0)
3277
3278 #ifdef CONFIG_SMP
3279 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3280  * counters. So we need to make sure we have free clusters more
3281  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3282  */
3283 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3284 #else
3285 #define EXT4_FREECLUSTERS_WATERMARK 0
3286 #endif
3287
3288 /* Update i_disksize. Requires i_rwsem to avoid races with truncate */
3289 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3290 {
3291         WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3292                      !inode_is_locked(inode));
3293         down_write(&EXT4_I(inode)->i_data_sem);
3294         if (newsize > EXT4_I(inode)->i_disksize)
3295                 WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3296         up_write(&EXT4_I(inode)->i_data_sem);
3297 }
3298
3299 /* Update i_size, i_disksize. Requires i_rwsem to avoid races with truncate */
3300 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3301 {
3302         int changed = 0;
3303
3304         if (newsize > inode->i_size) {
3305                 i_size_write(inode, newsize);
3306                 changed = 1;
3307         }
3308         if (newsize > EXT4_I(inode)->i_disksize) {
3309                 ext4_update_i_disksize(inode, newsize);
3310                 changed |= 2;
3311         }
3312         return changed;
3313 }
3314
3315 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3316                                       loff_t len);
3317
3318 struct ext4_group_info {
3319         unsigned long   bb_state;
3320 #ifdef AGGRESSIVE_CHECK
3321         unsigned long   bb_check_counter;
3322 #endif
3323         struct rb_root  bb_free_root;
3324         ext4_grpblk_t   bb_first_free;  /* first free block */
3325         ext4_grpblk_t   bb_free;        /* total free blocks */
3326         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
3327         int             bb_avg_fragment_size_order;     /* order of average
3328                                                            fragment in BG */
3329         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
3330         ext4_group_t    bb_group;       /* Group number */
3331         struct          list_head bb_prealloc_list;
3332 #ifdef DOUBLE_CHECK
3333         void            *bb_bitmap;
3334 #endif
3335         struct rw_semaphore alloc_sem;
3336         struct list_head bb_avg_fragment_size_node;
3337         struct list_head bb_largest_free_order_node;
3338         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
3339                                          * regions, index is order.
3340                                          * bb_counters[3] = 5 means
3341                                          * 5 free 8-block regions. */
3342 };
3343
3344 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
3345 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
3346 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT     2
3347 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT     3
3348 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT         \
3349         (1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3350 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT         \
3351         (1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3352 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT        4
3353
3354 #define EXT4_MB_GRP_NEED_INIT(grp)      \
3355         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3356 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)        \
3357         (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3358 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)        \
3359         (test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3360
3361 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
3362         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3363 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
3364         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3365 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
3366         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3367 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)      \
3368         (test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3369
3370 #define EXT4_MAX_CONTENTION             8
3371 #define EXT4_CONTENTION_THRESHOLD       2
3372
3373 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3374                                               ext4_group_t group)
3375 {
3376         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3377 }
3378
3379 /*
3380  * Returns true if the filesystem is busy enough that attempts to
3381  * access the block group locks has run into contention.
3382  */
3383 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3384 {
3385         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3386 }
3387
3388 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3389 {
3390         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3391         if (spin_trylock(lock))
3392                 /*
3393                  * We're able to grab the lock right away, so drop the
3394                  * lock contention counter.
3395                  */
3396                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3397         else {
3398                 /*
3399                  * The lock is busy, so bump the contention counter,
3400                  * and then wait on the spin lock.
3401                  */
3402                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3403                                   EXT4_MAX_CONTENTION);
3404                 spin_lock(lock);
3405         }
3406 }
3407
3408 static inline void ext4_unlock_group(struct super_block *sb,
3409                                         ext4_group_t group)
3410 {
3411         spin_unlock(ext4_group_lock_ptr(sb, group));
3412 }
3413
3414 #ifdef CONFIG_QUOTA
3415 static inline bool ext4_quota_capable(struct super_block *sb)
3416 {
3417         return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
3418 }
3419
3420 static inline bool ext4_is_quota_journalled(struct super_block *sb)
3421 {
3422         struct ext4_sb_info *sbi = EXT4_SB(sb);
3423
3424         return (ext4_has_feature_quota(sb) ||
3425                 sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
3426 }
3427 int ext4_enable_quotas(struct super_block *sb);
3428 #endif
3429
3430 /*
3431  * Block validity checking
3432  */
3433 #define ext4_check_indirect_blockref(inode, bh)                         \
3434         ext4_check_blockref(__func__, __LINE__, inode,                  \
3435                             (__le32 *)(bh)->b_data,                     \
3436                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3437
3438 #define ext4_ind_check_inode(inode)                                     \
3439         ext4_check_blockref(__func__, __LINE__, inode,                  \
3440                             EXT4_I(inode)->i_data,                      \
3441                             EXT4_NDIR_BLOCKS)
3442
3443 /*
3444  * Inodes and files operations
3445  */
3446
3447 /* dir.c */
3448 extern const struct file_operations ext4_dir_operations;
3449
3450 /* file.c */
3451 extern const struct inode_operations ext4_file_inode_operations;
3452 extern const struct file_operations ext4_file_operations;
3453 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3454
3455 /* inline.c */
3456 extern int ext4_get_max_inline_size(struct inode *inode);
3457 extern int ext4_find_inline_data_nolock(struct inode *inode);
3458 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3459                                  unsigned int len);
3460 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3461
3462 int ext4_readpage_inline(struct inode *inode, struct folio *folio);
3463 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3464                                          struct inode *inode,
3465                                          loff_t pos, unsigned len,
3466                                          struct page **pagep);
3467 extern int ext4_write_inline_data_end(struct inode *inode,
3468                                       loff_t pos, unsigned len,
3469                                       unsigned copied,
3470                                       struct page *page);
3471 extern struct buffer_head *
3472 ext4_journalled_write_inline_data(struct inode *inode,
3473                                   unsigned len,
3474                                   struct page *page);
3475 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3476                                            struct inode *inode,
3477                                            loff_t pos, unsigned len,
3478                                            struct page **pagep,
3479                                            void **fsdata);
3480 extern int ext4_try_add_inline_entry(handle_t *handle,
3481                                      struct ext4_filename *fname,
3482                                      struct inode *dir, struct inode *inode);
3483 extern int ext4_try_create_inline_dir(handle_t *handle,
3484                                       struct inode *parent,
3485                                       struct inode *inode);
3486 extern int ext4_read_inline_dir(struct file *filp,
3487                                 struct dir_context *ctx,
3488                                 int *has_inline_data);
3489 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3490                                   struct inode *dir, ext4_lblk_t block,
3491                                   struct dx_hash_info *hinfo,
3492                                   __u32 start_hash, __u32 start_minor_hash,
3493                                   int *has_inline_data);
3494 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3495                                         struct ext4_filename *fname,
3496                                         struct ext4_dir_entry_2 **res_dir,
3497                                         int *has_inline_data);
3498 extern int ext4_delete_inline_entry(handle_t *handle,
3499                                     struct inode *dir,
3500                                     struct ext4_dir_entry_2 *de_del,
3501                                     struct buffer_head *bh,
3502                                     int *has_inline_data);
3503 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3504 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3505                                         struct ext4_dir_entry_2 **parent_de,
3506                                         int *retval);
3507 extern void *ext4_read_inline_link(struct inode *inode);
3508
3509 struct iomap;
3510 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3511
3512 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3513
3514 extern int ext4_convert_inline_data(struct inode *inode);
3515
3516 static inline int ext4_has_inline_data(struct inode *inode)
3517 {
3518         return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3519                EXT4_I(inode)->i_inline_off;
3520 }
3521
3522 /* namei.c */
3523 extern const struct inode_operations ext4_dir_inode_operations;
3524 extern const struct inode_operations ext4_special_inode_operations;
3525 extern struct dentry *ext4_get_parent(struct dentry *child);
3526 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3527                                  struct ext4_dir_entry_2 *de,
3528                                  int blocksize, int csum_size,
3529                                  unsigned int parent_ino, int dotdot_real_len);
3530 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3531                                         unsigned int blocksize);
3532 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3533                                       struct buffer_head *bh);
3534 extern int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
3535                          struct inode *inode, struct dentry *dentry);
3536 extern int __ext4_link(struct inode *dir, struct inode *inode,
3537                        struct dentry *dentry);
3538
3539 #define S_SHIFT 12
3540 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3541         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
3542         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
3543         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
3544         [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
3545         [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
3546         [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
3547         [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
3548 };
3549
3550 static inline void ext4_set_de_type(struct super_block *sb,
3551                                 struct ext4_dir_entry_2 *de,
3552                                 umode_t mode) {
3553         if (ext4_has_feature_filetype(sb))
3554                 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3555 }
3556
3557 /* readpages.c */
3558 extern int ext4_mpage_readpages(struct inode *inode,
3559                 struct readahead_control *rac, struct folio *folio);
3560 extern int __init ext4_init_post_read_processing(void);
3561 extern void ext4_exit_post_read_processing(void);
3562
3563 /* symlink.c */
3564 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3565 extern const struct inode_operations ext4_symlink_inode_operations;
3566 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3567
3568 /* sysfs.c */
3569 extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
3570 extern int ext4_register_sysfs(struct super_block *sb);
3571 extern void ext4_unregister_sysfs(struct super_block *sb);
3572 extern int __init ext4_init_sysfs(void);
3573 extern void ext4_exit_sysfs(void);
3574
3575 /* block_validity */
3576 extern void ext4_release_system_zone(struct super_block *sb);
3577 extern int ext4_setup_system_zone(struct super_block *sb);
3578 extern int __init ext4_init_system_zone(void);
3579 extern void ext4_exit_system_zone(void);
3580 extern int ext4_inode_block_valid(struct inode *inode,
3581                                   ext4_fsblk_t start_blk,
3582                                   unsigned int count);
3583 extern int ext4_check_blockref(const char *, unsigned int,
3584                                struct inode *, __le32 *, unsigned int);
3585 extern int ext4_sb_block_valid(struct super_block *sb, struct inode *inode,
3586                                 ext4_fsblk_t start_blk, unsigned int count);
3587
3588
3589 /* extents.c */
3590 struct ext4_ext_path;
3591 struct ext4_extent;
3592
3593 /*
3594  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3595  * __le32.
3596  */
3597 #define EXT_MAX_BLOCKS  0xffffffff
3598
3599 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3600 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3601 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3602                                struct ext4_map_blocks *map, int flags);
3603 extern int ext4_ext_truncate(handle_t *, struct inode *);
3604 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3605                                  ext4_lblk_t end);
3606 extern void ext4_ext_init(struct super_block *);
3607 extern void ext4_ext_release(struct super_block *);
3608 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3609                           loff_t len);
3610 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3611                                           loff_t offset, ssize_t len);
3612 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3613                                              ext4_io_end_t *io_end);
3614 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3615                            struct ext4_map_blocks *map, int flags);
3616 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3617                                                    int num,
3618                                                    struct ext4_ext_path *path);
3619 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3620                                   struct ext4_ext_path **,
3621                                   struct ext4_extent *, int);
3622 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3623                                               struct ext4_ext_path **,
3624                                               int flags);
3625 extern void ext4_free_ext_path(struct ext4_ext_path *);
3626 extern int ext4_ext_check_inode(struct inode *inode);
3627 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3628 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3629                         __u64 start, __u64 len);
3630 extern int ext4_get_es_cache(struct inode *inode,
3631                              struct fiemap_extent_info *fieinfo,
3632                              __u64 start, __u64 len);
3633 extern int ext4_ext_precache(struct inode *inode);
3634 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3635                                 struct inode *inode2, ext4_lblk_t lblk1,
3636                              ext4_lblk_t lblk2,  ext4_lblk_t count,
3637                              int mark_unwritten,int *err);
3638 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3639 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3640                                        int check_cred, int restart_cred,
3641                                        int revoke_cred);
3642 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3643 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3644 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3645                 int len, int unwritten, ext4_fsblk_t pblk);
3646 extern int ext4_ext_clear_bb(struct inode *inode);
3647
3648
3649 /* move_extent.c */
3650 extern void ext4_double_down_write_data_sem(struct inode *first,
3651                                             struct inode *second);
3652 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3653                                           struct inode *donor_inode);
3654 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3655                              __u64 start_orig, __u64 start_donor,
3656                              __u64 len, __u64 *moved_len);
3657
3658 /* page-io.c */
3659 extern int __init ext4_init_pageio(void);
3660 extern void ext4_exit_pageio(void);
3661 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3662 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3663 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3664 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3665 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3666                                 struct writeback_control *wbc);
3667 extern void ext4_end_io_rsv_work(struct work_struct *work);
3668 extern void ext4_io_submit(struct ext4_io_submit *io);
3669 int ext4_bio_write_folio(struct ext4_io_submit *io, struct folio *page,
3670                 size_t len);
3671 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3672 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3673
3674 /* mmp.c */
3675 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3676
3677 /* mmp.c */
3678 extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
3679
3680 /* verity.c */
3681 extern const struct fsverity_operations ext4_verityops;
3682
3683 /* orphan.c */
3684 extern int ext4_orphan_add(handle_t *, struct inode *);
3685 extern int ext4_orphan_del(handle_t *, struct inode *);
3686 extern void ext4_orphan_cleanup(struct super_block *sb,
3687                                 struct ext4_super_block *es);
3688 extern void ext4_release_orphan_info(struct super_block *sb);
3689 extern int ext4_init_orphan_info(struct super_block *sb);
3690 extern int ext4_orphan_file_empty(struct super_block *sb);
3691 extern void ext4_orphan_file_block_trigger(
3692                                 struct jbd2_buffer_trigger_type *triggers,
3693                                 struct buffer_head *bh,
3694                                 void *data, size_t size);
3695
3696 /*
3697  * Add new method to test whether block and inode bitmaps are properly
3698  * initialized. With uninit_bg reading the block from disk is not enough
3699  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3700  */
3701 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3702
3703 static inline int bitmap_uptodate(struct buffer_head *bh)
3704 {
3705         return (buffer_uptodate(bh) &&
3706                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3707 }
3708 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3709 {
3710         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3711 }
3712
3713 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
3714
3715 /* For ioend & aio unwritten conversion wait queues */
3716 #define EXT4_WQ_HASH_SZ         37
3717 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3718                                             EXT4_WQ_HASH_SZ])
3719 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3720
3721 extern int ext4_resize_begin(struct super_block *sb);
3722 extern int ext4_resize_end(struct super_block *sb, bool update_backups);
3723
3724 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3725                                               struct ext4_io_end *io_end)
3726 {
3727         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3728                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
3729                 atomic_inc(&EXT4_I(inode)->i_unwritten);
3730         }
3731 }
3732
3733 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3734 {
3735         struct inode *inode = io_end->inode;
3736
3737         if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3738                 io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3739                 /* Wake up anyone waiting on unwritten extent conversion */
3740                 if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3741                         wake_up_all(ext4_ioend_wq(inode));
3742         }
3743 }
3744
3745 extern const struct iomap_ops ext4_iomap_ops;
3746 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3747 extern const struct iomap_ops ext4_iomap_report_ops;
3748
3749 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3750 {
3751         /*
3752          * If the buffer has the write error flag, we have failed
3753          * to write out data in the block.  In this  case, we don't
3754          * have to read the block because we may read the old data
3755          * successfully.
3756          */
3757         if (buffer_write_io_error(bh))
3758                 set_buffer_uptodate(bh);
3759         return buffer_uptodate(bh);
3760 }
3761
3762 #endif  /* __KERNEL__ */
3763
3764 #define EFSBADCRC       EBADMSG         /* Bad CRC detected */
3765 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
3766
3767 #endif  /* _EXT4_H */