Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso...
[linux-2.6-microblaze.git] / fs / ext4 / ext4.h
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16
17 #ifndef _EXT4_H
18 #define _EXT4_H
19
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/wait.h>
31 #include <linux/sched/signal.h>
32 #include <linux/blockgroup_lock.h>
33 #include <linux/percpu_counter.h>
34 #include <linux/ratelimit.h>
35 #include <crypto/hash.h>
36 #include <linux/falloc.h>
37 #include <linux/percpu-rwsem.h>
38 #include <linux/fiemap.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42
43 #include <linux/fscrypt.h>
44 #include <linux/fsverity.h>
45
46 #include <linux/compiler.h>
47
48 /*
49  * The fourth extended filesystem constants/structures
50  */
51
52 /*
53  * with AGGRESSIVE_CHECK allocator runs consistency checks over
54  * structures. these checks slow things down a lot
55  */
56 #define AGGRESSIVE_CHECK__
57
58 /*
59  * with DOUBLE_CHECK defined mballoc creates persistent in-core
60  * bitmaps, maintains and uses them to check for double allocations
61  */
62 #define DOUBLE_CHECK__
63
64 /*
65  * Define EXT4FS_DEBUG to produce debug messages
66  */
67 #undef EXT4FS_DEBUG
68
69 /*
70  * Debug code
71  */
72 #ifdef EXT4FS_DEBUG
73 #define ext4_debug(f, a...)                                             \
74         do {                                                            \
75                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
76                         __FILE__, __LINE__, __func__);                  \
77                 printk(KERN_DEBUG f, ## a);                             \
78         } while (0)
79 #else
80 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
81 #endif
82
83  /*
84   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
85   */
86 #define EXT_DEBUG__
87
88 /*
89  * Dynamic printk for controlled extents debugging.
90  */
91 #ifdef CONFIG_EXT4_DEBUG
92 #define ext_debug(ino, fmt, ...)                                        \
93         pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,    \
94                  current->comm, task_pid_nr(current),                   \
95                  ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,       \
96                  __func__, ##__VA_ARGS__)
97 #else
98 #define ext_debug(ino, fmt, ...)        no_printk(fmt, ##__VA_ARGS__)
99 #endif
100
101 #define ASSERT(assert)                                          \
102 do {                                                                    \
103         if (unlikely(!(assert))) {                                      \
104                 printk(KERN_EMERG                                       \
105                        "Assertion failure in %s() at %s:%d: '%s'\n",    \
106                        __func__, __FILE__, __LINE__, #assert);          \
107                 BUG();                                                  \
108         }                                                               \
109 } while (0)
110
111 /* data type for block offset of block group */
112 typedef int ext4_grpblk_t;
113
114 /* data type for filesystem-wide blocks number */
115 typedef unsigned long long ext4_fsblk_t;
116
117 /* data type for file logical block number */
118 typedef __u32 ext4_lblk_t;
119
120 /* data type for block group number */
121 typedef unsigned int ext4_group_t;
122
123 enum SHIFT_DIRECTION {
124         SHIFT_LEFT = 0,
125         SHIFT_RIGHT,
126 };
127
128 /*
129  * Flags used in mballoc's allocation_context flags field.
130  *
131  * Also used to show what's going on for debugging purposes when the
132  * flag field is exported via the traceport interface
133  */
134
135 /* prefer goal again. length */
136 #define EXT4_MB_HINT_MERGE              0x0001
137 /* blocks already reserved */
138 #define EXT4_MB_HINT_RESERVED           0x0002
139 /* metadata is being allocated */
140 #define EXT4_MB_HINT_METADATA           0x0004
141 /* first blocks in the file */
142 #define EXT4_MB_HINT_FIRST              0x0008
143 /* search for the best chunk */
144 #define EXT4_MB_HINT_BEST               0x0010
145 /* data is being allocated */
146 #define EXT4_MB_HINT_DATA               0x0020
147 /* don't preallocate (for tails) */
148 #define EXT4_MB_HINT_NOPREALLOC         0x0040
149 /* allocate for locality group */
150 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
151 /* allocate goal blocks or none */
152 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
153 /* goal is meaningful */
154 #define EXT4_MB_HINT_TRY_GOAL           0x0200
155 /* blocks already pre-reserved by delayed allocation */
156 #define EXT4_MB_DELALLOC_RESERVED       0x0400
157 /* We are doing stream allocation */
158 #define EXT4_MB_STREAM_ALLOC            0x0800
159 /* Use reserved root blocks if needed */
160 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
161 /* Use blocks from reserved pool */
162 #define EXT4_MB_USE_RESERVED            0x2000
163 /* Do strict check for free blocks while retrying block allocation */
164 #define EXT4_MB_STRICT_CHECK            0x4000
165
166 struct ext4_allocation_request {
167         /* target inode for block we're allocating */
168         struct inode *inode;
169         /* how many blocks we want to allocate */
170         unsigned int len;
171         /* logical block in target inode */
172         ext4_lblk_t logical;
173         /* the closest logical allocated block to the left */
174         ext4_lblk_t lleft;
175         /* the closest logical allocated block to the right */
176         ext4_lblk_t lright;
177         /* phys. target (a hint) */
178         ext4_fsblk_t goal;
179         /* phys. block for the closest logical allocated block to the left */
180         ext4_fsblk_t pleft;
181         /* phys. block for the closest logical allocated block to the right */
182         ext4_fsblk_t pright;
183         /* flags. see above EXT4_MB_HINT_* */
184         unsigned int flags;
185 };
186
187 /*
188  * Logical to physical block mapping, used by ext4_map_blocks()
189  *
190  * This structure is used to pass requests into ext4_map_blocks() as
191  * well as to store the information returned by ext4_map_blocks().  It
192  * takes less room on the stack than a struct buffer_head.
193  */
194 #define EXT4_MAP_NEW            BIT(BH_New)
195 #define EXT4_MAP_MAPPED         BIT(BH_Mapped)
196 #define EXT4_MAP_UNWRITTEN      BIT(BH_Unwritten)
197 #define EXT4_MAP_BOUNDARY       BIT(BH_Boundary)
198 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
199                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
200
201 struct ext4_map_blocks {
202         ext4_fsblk_t m_pblk;
203         ext4_lblk_t m_lblk;
204         unsigned int m_len;
205         unsigned int m_flags;
206 };
207
208 /*
209  * Block validity checking, system zone rbtree.
210  */
211 struct ext4_system_blocks {
212         struct rb_root root;
213         struct rcu_head rcu;
214 };
215
216 /*
217  * Flags for ext4_io_end->flags
218  */
219 #define EXT4_IO_END_UNWRITTEN   0x0001
220
221 struct ext4_io_end_vec {
222         struct list_head list;          /* list of io_end_vec */
223         loff_t offset;                  /* offset in the file */
224         ssize_t size;                   /* size of the extent */
225 };
226
227 /*
228  * For converting unwritten extents on a work queue. 'handle' is used for
229  * buffered writeback.
230  */
231 typedef struct ext4_io_end {
232         struct list_head        list;           /* per-file finished IO list */
233         handle_t                *handle;        /* handle reserved for extent
234                                                  * conversion */
235         struct inode            *inode;         /* file being written to */
236         struct bio              *bio;           /* Linked list of completed
237                                                  * bios covering the extent */
238         unsigned int            flag;           /* unwritten or not */
239         atomic_t                count;          /* reference counter */
240         struct list_head        list_vec;       /* list of ext4_io_end_vec */
241 } ext4_io_end_t;
242
243 struct ext4_io_submit {
244         struct writeback_control *io_wbc;
245         struct bio              *io_bio;
246         ext4_io_end_t           *io_end;
247         sector_t                io_next_block;
248 };
249
250 /*
251  * Special inodes numbers
252  */
253 #define EXT4_BAD_INO             1      /* Bad blocks inode */
254 #define EXT4_ROOT_INO            2      /* Root inode */
255 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
256 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
257 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
258 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
259 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
260 #define EXT4_JOURNAL_INO         8      /* Journal inode */
261
262 /* First non-reserved inode for old ext4 filesystems */
263 #define EXT4_GOOD_OLD_FIRST_INO 11
264
265 /*
266  * Maximal count of links to a file
267  */
268 #define EXT4_LINK_MAX           65000
269
270 /*
271  * Macro-instructions used to manage several block sizes
272  */
273 #define EXT4_MIN_BLOCK_SIZE             1024
274 #define EXT4_MAX_BLOCK_SIZE             65536
275 #define EXT4_MIN_BLOCK_LOG_SIZE         10
276 #define EXT4_MAX_BLOCK_LOG_SIZE         16
277 #define EXT4_MAX_CLUSTER_LOG_SIZE       30
278 #ifdef __KERNEL__
279 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
280 #else
281 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
282 #endif
283 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
284 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
285                                          EXT4_SB(s)->s_cluster_bits)
286 #ifdef __KERNEL__
287 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
288 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
289 #else
290 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
291 #endif
292 #ifdef __KERNEL__
293 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
294 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
295 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
296 #else
297 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
298                                  EXT4_GOOD_OLD_INODE_SIZE : \
299                                  (s)->s_inode_size)
300 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
301                                  EXT4_GOOD_OLD_FIRST_INO : \
302                                  (s)->s_first_ino)
303 #endif
304 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
305 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
306         ((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
307                                                                   blkbits))
308
309 /* Translate a block number to a cluster number */
310 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
311 /* Translate a cluster number to a block number */
312 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
313 /* Translate # of blks to # of clusters */
314 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
315                                  (sbi)->s_cluster_bits)
316 /* Mask out the low bits to get the starting block of the cluster */
317 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &                              \
318                                   ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
319 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &                              \
320                                   ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
321 /* Fill in the low bits to get the last block of the cluster */
322 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |                            \
323                                     ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
324 /* Get the cluster offset */
325 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &                               \
326                                  ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
327 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &                               \
328                                  ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
329
330 /*
331  * Structure of a blocks group descriptor
332  */
333 struct ext4_group_desc
334 {
335         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
336         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
337         __le32  bg_inode_table_lo;      /* Inodes table block */
338         __le16  bg_free_blocks_count_lo;/* Free blocks count */
339         __le16  bg_free_inodes_count_lo;/* Free inodes count */
340         __le16  bg_used_dirs_count_lo;  /* Directories count */
341         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
342         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
343         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
344         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
345         __le16  bg_itable_unused_lo;    /* Unused inodes count */
346         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
347         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
348         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
349         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
350         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
351         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
352         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
353         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
354         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
355         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
356         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
357         __u32   bg_reserved;
358 };
359
360 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
361         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
362          sizeof(__le16))
363 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
364         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
365          sizeof(__le16))
366
367 /*
368  * Structure of a flex block group info
369  */
370
371 struct flex_groups {
372         atomic64_t      free_clusters;
373         atomic_t        free_inodes;
374         atomic_t        used_dirs;
375 };
376
377 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
378 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
379 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
380
381 /*
382  * Macro-instructions used to manage group descriptors
383  */
384 #define EXT4_MIN_DESC_SIZE              32
385 #define EXT4_MIN_DESC_SIZE_64BIT        64
386 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
387 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
388 #ifdef __KERNEL__
389 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
390 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
391 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
392 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
393 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
394 #else
395 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
396 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
397 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
398 #endif
399
400 /*
401  * Constants relative to the data blocks
402  */
403 #define EXT4_NDIR_BLOCKS                12
404 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
405 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
406 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
407 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
408
409 /*
410  * Inode flags
411  */
412 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
413 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
414 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
415 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
416 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
417 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
418 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
419 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
420 /* Reserved for compression usage... */
421 #define EXT4_DIRTY_FL                   0x00000100
422 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
423 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
424         /* nb: was previously EXT2_ECOMPR_FL */
425 #define EXT4_ENCRYPT_FL                 0x00000800 /* encrypted file */
426 /* End compression flags --- maybe not all used */
427 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
428 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
429 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
430 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
431 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
432 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
433 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
434 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
435 #define EXT4_VERITY_FL                  0x00100000 /* Verity protected inode */
436 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
437 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
438
439 #define EXT4_DAX_FL                     0x02000000 /* Inode is DAX */
440
441 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
442 #define EXT4_PROJINHERIT_FL             0x20000000 /* Create with parents projid */
443 #define EXT4_CASEFOLD_FL                0x40000000 /* Casefolded directory */
444 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
445
446 /* User modifiable flags */
447 #define EXT4_FL_USER_MODIFIABLE         (EXT4_SECRM_FL | \
448                                          EXT4_UNRM_FL | \
449                                          EXT4_COMPR_FL | \
450                                          EXT4_SYNC_FL | \
451                                          EXT4_IMMUTABLE_FL | \
452                                          EXT4_APPEND_FL | \
453                                          EXT4_NODUMP_FL | \
454                                          EXT4_NOATIME_FL | \
455                                          EXT4_JOURNAL_DATA_FL | \
456                                          EXT4_NOTAIL_FL | \
457                                          EXT4_DIRSYNC_FL | \
458                                          EXT4_TOPDIR_FL | \
459                                          EXT4_EXTENTS_FL | \
460                                          0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
461                                          EXT4_DAX_FL | \
462                                          EXT4_PROJINHERIT_FL | \
463                                          EXT4_CASEFOLD_FL)
464
465 /* User visible flags */
466 #define EXT4_FL_USER_VISIBLE            (EXT4_FL_USER_MODIFIABLE | \
467                                          EXT4_DIRTY_FL | \
468                                          EXT4_COMPRBLK_FL | \
469                                          EXT4_NOCOMPR_FL | \
470                                          EXT4_ENCRYPT_FL | \
471                                          EXT4_INDEX_FL | \
472                                          EXT4_VERITY_FL | \
473                                          EXT4_INLINE_DATA_FL)
474
475 /* Flags we can manipulate with through FS_IOC_FSSETXATTR */
476 #define EXT4_FL_XFLAG_VISIBLE           (EXT4_SYNC_FL | \
477                                          EXT4_IMMUTABLE_FL | \
478                                          EXT4_APPEND_FL | \
479                                          EXT4_NODUMP_FL | \
480                                          EXT4_NOATIME_FL | \
481                                          EXT4_PROJINHERIT_FL | \
482                                          EXT4_DAX_FL)
483
484 /* Flags that should be inherited by new inodes from their parent. */
485 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
486                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
487                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
488                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
489                            EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
490                            EXT4_DAX_FL)
491
492 /* Flags that are appropriate for regular files (all but dir-specific ones). */
493 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
494                            EXT4_PROJINHERIT_FL))
495
496 /* Flags that are appropriate for non-directories/regular files. */
497 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
498
499 /* The only flags that should be swapped */
500 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
501
502 /* Flags which are mutually exclusive to DAX */
503 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
504                            EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_FL)
505
506 /* Mask out flags that are inappropriate for the given type of inode. */
507 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
508 {
509         if (S_ISDIR(mode))
510                 return flags;
511         else if (S_ISREG(mode))
512                 return flags & EXT4_REG_FLMASK;
513         else
514                 return flags & EXT4_OTHER_FLMASK;
515 }
516
517 /*
518  * Inode flags used for atomic set/get
519  */
520 enum {
521         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
522         EXT4_INODE_UNRM         = 1,    /* Undelete */
523         EXT4_INODE_COMPR        = 2,    /* Compress file */
524         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
525         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
526         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
527         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
528         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
529 /* Reserved for compression usage... */
530         EXT4_INODE_DIRTY        = 8,
531         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
532         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
533         EXT4_INODE_ENCRYPT      = 11,   /* Encrypted file */
534 /* End compression flags --- maybe not all used */
535         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
536         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
537         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
538         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
539         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
540         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
541         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
542         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
543         EXT4_INODE_VERITY       = 20,   /* Verity protected inode */
544         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
545 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
546         EXT4_INODE_DAX          = 25,   /* Inode is DAX */
547         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
548         EXT4_INODE_PROJINHERIT  = 29,   /* Create with parents projid */
549         EXT4_INODE_CASEFOLD     = 30,   /* Casefolded directory */
550         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
551 };
552
553 /*
554  * Since it's pretty easy to mix up bit numbers and hex values, we use a
555  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
556  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
557  * any extra space in the compiled kernel image, otherwise, the build will fail.
558  * It's important that these values are the same, since we are using
559  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
560  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
561  * values found in ext2, ext3 and ext4 filesystems, and of course the values
562  * defined in e2fsprogs.
563  *
564  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
565  */
566 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
567 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
568
569 static inline void ext4_check_flag_values(void)
570 {
571         CHECK_FLAG_VALUE(SECRM);
572         CHECK_FLAG_VALUE(UNRM);
573         CHECK_FLAG_VALUE(COMPR);
574         CHECK_FLAG_VALUE(SYNC);
575         CHECK_FLAG_VALUE(IMMUTABLE);
576         CHECK_FLAG_VALUE(APPEND);
577         CHECK_FLAG_VALUE(NODUMP);
578         CHECK_FLAG_VALUE(NOATIME);
579         CHECK_FLAG_VALUE(DIRTY);
580         CHECK_FLAG_VALUE(COMPRBLK);
581         CHECK_FLAG_VALUE(NOCOMPR);
582         CHECK_FLAG_VALUE(ENCRYPT);
583         CHECK_FLAG_VALUE(INDEX);
584         CHECK_FLAG_VALUE(IMAGIC);
585         CHECK_FLAG_VALUE(JOURNAL_DATA);
586         CHECK_FLAG_VALUE(NOTAIL);
587         CHECK_FLAG_VALUE(DIRSYNC);
588         CHECK_FLAG_VALUE(TOPDIR);
589         CHECK_FLAG_VALUE(HUGE_FILE);
590         CHECK_FLAG_VALUE(EXTENTS);
591         CHECK_FLAG_VALUE(VERITY);
592         CHECK_FLAG_VALUE(EA_INODE);
593         CHECK_FLAG_VALUE(INLINE_DATA);
594         CHECK_FLAG_VALUE(PROJINHERIT);
595         CHECK_FLAG_VALUE(CASEFOLD);
596         CHECK_FLAG_VALUE(RESERVED);
597 }
598
599 /* Used to pass group descriptor data when online resize is done */
600 struct ext4_new_group_input {
601         __u32 group;            /* Group number for this data */
602         __u64 block_bitmap;     /* Absolute block number of block bitmap */
603         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
604         __u64 inode_table;      /* Absolute block number of inode table start */
605         __u32 blocks_count;     /* Total number of blocks in this group */
606         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
607         __u16 unused;
608 };
609
610 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
611 struct compat_ext4_new_group_input {
612         u32 group;
613         compat_u64 block_bitmap;
614         compat_u64 inode_bitmap;
615         compat_u64 inode_table;
616         u32 blocks_count;
617         u16 reserved_blocks;
618         u16 unused;
619 };
620 #endif
621
622 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
623 struct ext4_new_group_data {
624         __u32 group;
625         __u64 block_bitmap;
626         __u64 inode_bitmap;
627         __u64 inode_table;
628         __u32 blocks_count;
629         __u16 reserved_blocks;
630         __u16 mdata_blocks;
631         __u32 free_clusters_count;
632 };
633
634 /* Indexes used to index group tables in ext4_new_group_data */
635 enum {
636         BLOCK_BITMAP = 0,       /* block bitmap */
637         INODE_BITMAP,           /* inode bitmap */
638         INODE_TABLE,            /* inode tables */
639         GROUP_TABLE_COUNT,
640 };
641
642 /*
643  * Flags used by ext4_map_blocks()
644  */
645         /* Allocate any needed blocks and/or convert an unwritten
646            extent to be an initialized ext4 */
647 #define EXT4_GET_BLOCKS_CREATE                  0x0001
648         /* Request the creation of an unwritten extent */
649 #define EXT4_GET_BLOCKS_UNWRIT_EXT              0x0002
650 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT       (EXT4_GET_BLOCKS_UNWRIT_EXT|\
651                                                  EXT4_GET_BLOCKS_CREATE)
652         /* Caller is from the delayed allocation writeout path
653          * finally doing the actual allocation of delayed blocks */
654 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
655         /* caller is from the direct IO path, request to creation of an
656         unwritten extents if not allocated, split the unwritten
657         extent if blocks has been preallocated already*/
658 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
659 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
660 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
661                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
662         /* Convert extent to initialized after IO complete */
663 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
664                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
665         /* Eventual metadata allocation (due to growing extent tree)
666          * should not fail, so try to use reserved blocks for that.*/
667 #define EXT4_GET_BLOCKS_METADATA_NOFAIL         0x0020
668         /* Don't normalize allocation size (used for fallocate) */
669 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
670         /* Convert written extents to unwritten */
671 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN       0x0100
672         /* Write zeros to newly created written extents */
673 #define EXT4_GET_BLOCKS_ZERO                    0x0200
674 #define EXT4_GET_BLOCKS_CREATE_ZERO             (EXT4_GET_BLOCKS_CREATE |\
675                                         EXT4_GET_BLOCKS_ZERO)
676         /* Caller will submit data before dropping transaction handle. This
677          * allows jbd2 to avoid submitting data before commit. */
678 #define EXT4_GET_BLOCKS_IO_SUBMIT               0x0400
679
680 /*
681  * The bit position of these flags must not overlap with any of the
682  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
683  * read_extent_tree_block(), ext4_split_extent_at(),
684  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
685  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
686  * caching the extents when reading from the extent tree while a
687  * truncate or punch hole operation is in progress.
688  */
689 #define EXT4_EX_NOCACHE                         0x40000000
690 #define EXT4_EX_FORCE_CACHE                     0x20000000
691 #define EXT4_EX_NOFAIL                          0x10000000
692
693 /*
694  * Flags used by ext4_free_blocks
695  */
696 #define EXT4_FREE_BLOCKS_METADATA               0x0001
697 #define EXT4_FREE_BLOCKS_FORGET                 0x0002
698 #define EXT4_FREE_BLOCKS_VALIDATED              0x0004
699 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE         0x0008
700 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
701 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
702 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
703
704 /*
705  * ioctl commands
706  */
707 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
708 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
709 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
710 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
711 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
712 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
713 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
714 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
715 #define EXT4_IOC_MIGRATE                _IO('f', 9)
716  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
717  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
718 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
719 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
720 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
721 #define EXT4_IOC_SWAP_BOOT              _IO('f', 17)
722 #define EXT4_IOC_PRECACHE_EXTENTS       _IO('f', 18)
723 /* ioctl codes 19--39 are reserved for fscrypt */
724 #define EXT4_IOC_CLEAR_ES_CACHE         _IO('f', 40)
725 #define EXT4_IOC_GETSTATE               _IOW('f', 41, __u32)
726 #define EXT4_IOC_GET_ES_CACHE           _IOWR('f', 42, struct fiemap)
727
728 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
729
730 /*
731  * Flags for going down operation
732  */
733 #define EXT4_GOING_FLAGS_DEFAULT                0x0     /* going down */
734 #define EXT4_GOING_FLAGS_LOGFLUSH               0x1     /* flush log but not data */
735 #define EXT4_GOING_FLAGS_NOLOGFLUSH             0x2     /* don't flush log nor data */
736
737 /*
738  * Flags returned by EXT4_IOC_GETSTATE
739  *
740  * We only expose to userspace a subset of the state flags in
741  * i_state_flags
742  */
743 #define EXT4_STATE_FLAG_EXT_PRECACHED   0x00000001
744 #define EXT4_STATE_FLAG_NEW             0x00000002
745 #define EXT4_STATE_FLAG_NEWENTRY        0x00000004
746 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE  0x00000008
747
748 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
749 /*
750  * ioctl commands in 32 bit emulation
751  */
752 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
753 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
754 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
755 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
756 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
757 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
758 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
759 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
760 #endif
761
762 /*
763  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
764  * It indicates that the entry in extent status cache is for a hole.
765  */
766 #define EXT4_FIEMAP_EXTENT_HOLE         0x08000000
767
768 /* Max physical block we can address w/o extents */
769 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
770
771 /* Max logical block we can support */
772 #define EXT4_MAX_LOGICAL_BLOCK          0xFFFFFFFE
773
774 /*
775  * Structure of an inode on the disk
776  */
777 struct ext4_inode {
778         __le16  i_mode;         /* File mode */
779         __le16  i_uid;          /* Low 16 bits of Owner Uid */
780         __le32  i_size_lo;      /* Size in bytes */
781         __le32  i_atime;        /* Access time */
782         __le32  i_ctime;        /* Inode Change time */
783         __le32  i_mtime;        /* Modification time */
784         __le32  i_dtime;        /* Deletion Time */
785         __le16  i_gid;          /* Low 16 bits of Group Id */
786         __le16  i_links_count;  /* Links count */
787         __le32  i_blocks_lo;    /* Blocks count */
788         __le32  i_flags;        /* File flags */
789         union {
790                 struct {
791                         __le32  l_i_version;
792                 } linux1;
793                 struct {
794                         __u32  h_i_translator;
795                 } hurd1;
796                 struct {
797                         __u32  m_i_reserved1;
798                 } masix1;
799         } osd1;                         /* OS dependent 1 */
800         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
801         __le32  i_generation;   /* File version (for NFS) */
802         __le32  i_file_acl_lo;  /* File ACL */
803         __le32  i_size_high;
804         __le32  i_obso_faddr;   /* Obsoleted fragment address */
805         union {
806                 struct {
807                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
808                         __le16  l_i_file_acl_high;
809                         __le16  l_i_uid_high;   /* these 2 fields */
810                         __le16  l_i_gid_high;   /* were reserved2[0] */
811                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
812                         __le16  l_i_reserved;
813                 } linux2;
814                 struct {
815                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
816                         __u16   h_i_mode_high;
817                         __u16   h_i_uid_high;
818                         __u16   h_i_gid_high;
819                         __u32   h_i_author;
820                 } hurd2;
821                 struct {
822                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
823                         __le16  m_i_file_acl_high;
824                         __u32   m_i_reserved2[2];
825                 } masix2;
826         } osd2;                         /* OS dependent 2 */
827         __le16  i_extra_isize;
828         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
829         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
830         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
831         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
832         __le32  i_crtime;       /* File Creation time */
833         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
834         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
835         __le32  i_projid;       /* Project ID */
836 };
837
838 struct move_extent {
839         __u32 reserved;         /* should be zero */
840         __u32 donor_fd;         /* donor file descriptor */
841         __u64 orig_start;       /* logical start offset in block for orig */
842         __u64 donor_start;      /* logical start offset in block for donor */
843         __u64 len;              /* block length to be moved */
844         __u64 moved_len;        /* moved block length */
845 };
846
847 #define EXT4_EPOCH_BITS 2
848 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
849 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
850
851 /*
852  * Extended fields will fit into an inode if the filesystem was formatted
853  * with large inodes (-I 256 or larger) and there are not currently any EAs
854  * consuming all of the available space. For new inodes we always reserve
855  * enough space for the kernel's known extended fields, but for inodes
856  * created with an old kernel this might not have been the case. None of
857  * the extended inode fields is critical for correct filesystem operation.
858  * This macro checks if a certain field fits in the inode. Note that
859  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
860  */
861 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
862         ((offsetof(typeof(*ext4_inode), field) +        \
863           sizeof((ext4_inode)->field))                  \
864         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
865             (einode)->i_extra_isize))                   \
866
867 /*
868  * We use an encoding that preserves the times for extra epoch "00":
869  *
870  * extra  msb of                         adjust for signed
871  * epoch  32-bit                         32-bit tv_sec to
872  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
873  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
874  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
875  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
876  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
877  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
878  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
879  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
880  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
881  *
882  * Note that previous versions of the kernel on 64-bit systems would
883  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
884  * 1970.  e2fsck will correct this, assuming that it is run on the
885  * affected filesystem before 2242.
886  */
887
888 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
889 {
890         u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
891         return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
892 }
893
894 static inline void ext4_decode_extra_time(struct timespec64 *time,
895                                           __le32 extra)
896 {
897         if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
898                 time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
899         time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
900 }
901
902 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                           \
903 do {                                                                            \
904         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
905                 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);        \
906                 (raw_inode)->xtime ## _extra =                                  \
907                                 ext4_encode_extra_time(&(inode)->xtime);        \
908                 }                                                               \
909         else    \
910                 (raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));    \
911 } while (0)
912
913 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
914 do {                                                                           \
915         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
916                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
917         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
918                 (raw_inode)->xtime ## _extra =                                 \
919                                 ext4_encode_extra_time(&(einode)->xtime);      \
920 } while (0)
921
922 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                           \
923 do {                                                                            \
924         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);        \
925         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {    \
926                 ext4_decode_extra_time(&(inode)->xtime,                         \
927                                        raw_inode->xtime ## _extra);             \
928                 }                                                               \
929         else                                                                    \
930                 (inode)->xtime.tv_nsec = 0;                                     \
931 } while (0)
932
933
934 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
935 do {                                                                           \
936         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
937                 (einode)->xtime.tv_sec =                                       \
938                         (signed)le32_to_cpu((raw_inode)->xtime);               \
939         else                                                                   \
940                 (einode)->xtime.tv_sec = 0;                                    \
941         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
942                 ext4_decode_extra_time(&(einode)->xtime,                       \
943                                        raw_inode->xtime ## _extra);            \
944         else                                                                   \
945                 (einode)->xtime.tv_nsec = 0;                                   \
946 } while (0)
947
948 #define i_disk_version osd1.linux1.l_i_version
949
950 #if defined(__KERNEL__) || defined(__linux__)
951 #define i_reserved1     osd1.linux1.l_i_reserved1
952 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
953 #define i_blocks_high   osd2.linux2.l_i_blocks_high
954 #define i_uid_low       i_uid
955 #define i_gid_low       i_gid
956 #define i_uid_high      osd2.linux2.l_i_uid_high
957 #define i_gid_high      osd2.linux2.l_i_gid_high
958 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
959
960 #elif defined(__GNU__)
961
962 #define i_translator    osd1.hurd1.h_i_translator
963 #define i_uid_high      osd2.hurd2.h_i_uid_high
964 #define i_gid_high      osd2.hurd2.h_i_gid_high
965 #define i_author        osd2.hurd2.h_i_author
966
967 #elif defined(__masix__)
968
969 #define i_reserved1     osd1.masix1.m_i_reserved1
970 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
971 #define i_reserved2     osd2.masix2.m_i_reserved2
972
973 #endif /* defined(__KERNEL__) || defined(__linux__) */
974
975 #include "extents_status.h"
976 #include "fast_commit.h"
977
978 /*
979  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
980  *
981  * These are needed to avoid lockdep false positives when we need to
982  * allocate blocks to the quota inode during ext4_map_blocks(), while
983  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
984  * do quota tracking for the quota inode, this avoids deadlock (as
985  * well as infinite recursion, since it isn't turtles all the way
986  * down...)
987  *
988  *  I_DATA_SEM_NORMAL - Used for most inodes
989  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
990  *                        where the second inode has larger inode number
991  *                        than the first
992  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
993  */
994 enum {
995         I_DATA_SEM_NORMAL = 0,
996         I_DATA_SEM_OTHER,
997         I_DATA_SEM_QUOTA,
998 };
999
1000
1001 /*
1002  * fourth extended file system inode data in memory
1003  */
1004 struct ext4_inode_info {
1005         __le32  i_data[15];     /* unconverted */
1006         __u32   i_dtime;
1007         ext4_fsblk_t    i_file_acl;
1008
1009         /*
1010          * i_block_group is the number of the block group which contains
1011          * this file's inode.  Constant across the lifetime of the inode,
1012          * it is used for making block allocation decisions - we try to
1013          * place a file's data blocks near its inode block, and new inodes
1014          * near to their parent directory's inode.
1015          */
1016         ext4_group_t    i_block_group;
1017         ext4_lblk_t     i_dir_start_lookup;
1018 #if (BITS_PER_LONG < 64)
1019         unsigned long   i_state_flags;          /* Dynamic state flags */
1020 #endif
1021         unsigned long   i_flags;
1022
1023         /*
1024          * Extended attributes can be read independently of the main file
1025          * data. Taking i_mutex even when reading would cause contention
1026          * between readers of EAs and writers of regular file data, so
1027          * instead we synchronize on xattr_sem when reading or changing
1028          * EAs.
1029          */
1030         struct rw_semaphore xattr_sem;
1031
1032         struct list_head i_orphan;      /* unlinked but open inodes */
1033
1034         /* Fast commit related info */
1035
1036         struct list_head i_fc_list;     /*
1037                                          * inodes that need fast commit
1038                                          * protected by sbi->s_fc_lock.
1039                                          */
1040
1041         /* Start of lblk range that needs to be committed in this fast commit */
1042         ext4_lblk_t i_fc_lblk_start;
1043
1044         /* End of lblk range that needs to be committed in this fast commit */
1045         ext4_lblk_t i_fc_lblk_len;
1046
1047         /* Number of ongoing updates on this inode */
1048         atomic_t  i_fc_updates;
1049
1050         /* Fast commit wait queue for this inode */
1051         wait_queue_head_t i_fc_wait;
1052
1053         /* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
1054         struct mutex i_fc_lock;
1055
1056         /*
1057          * i_disksize keeps track of what the inode size is ON DISK, not
1058          * in memory.  During truncate, i_size is set to the new size by
1059          * the VFS prior to calling ext4_truncate(), but the filesystem won't
1060          * set i_disksize to 0 until the truncate is actually under way.
1061          *
1062          * The intent is that i_disksize always represents the blocks which
1063          * are used by this file.  This allows recovery to restart truncate
1064          * on orphans if we crash during truncate.  We actually write i_disksize
1065          * into the on-disk inode when writing inodes out, instead of i_size.
1066          *
1067          * The only time when i_disksize and i_size may be different is when
1068          * a truncate is in progress.  The only things which change i_disksize
1069          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1070          */
1071         loff_t  i_disksize;
1072
1073         /*
1074          * i_data_sem is for serialising ext4_truncate() against
1075          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1076          * data tree are chopped off during truncate. We can't do that in
1077          * ext4 because whenever we perform intermediate commits during
1078          * truncate, the inode and all the metadata blocks *must* be in a
1079          * consistent state which allows truncation of the orphans to restart
1080          * during recovery.  Hence we must fix the get_block-vs-truncate race
1081          * by other means, so we have i_data_sem.
1082          */
1083         struct rw_semaphore i_data_sem;
1084         /*
1085          * i_mmap_sem is for serializing page faults with truncate / punch hole
1086          * operations. We have to make sure that new page cannot be faulted in
1087          * a section of the inode that is being punched. We cannot easily use
1088          * i_data_sem for this since we need protection for the whole punch
1089          * operation and i_data_sem ranks below transaction start so we have
1090          * to occasionally drop it.
1091          */
1092         struct rw_semaphore i_mmap_sem;
1093         struct inode vfs_inode;
1094         struct jbd2_inode *jinode;
1095
1096         spinlock_t i_raw_lock;  /* protects updates to the raw inode */
1097
1098         /*
1099          * File creation time. Its function is same as that of
1100          * struct timespec64 i_{a,c,m}time in the generic inode.
1101          */
1102         struct timespec64 i_crtime;
1103
1104         /* mballoc */
1105         atomic_t i_prealloc_active;
1106         struct list_head i_prealloc_list;
1107         spinlock_t i_prealloc_lock;
1108
1109         /* extents status tree */
1110         struct ext4_es_tree i_es_tree;
1111         rwlock_t i_es_lock;
1112         struct list_head i_es_list;
1113         unsigned int i_es_all_nr;       /* protected by i_es_lock */
1114         unsigned int i_es_shk_nr;       /* protected by i_es_lock */
1115         ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
1116                                            extents to shrink. Protected by
1117                                            i_es_lock  */
1118
1119         /* ialloc */
1120         ext4_group_t    i_last_alloc_group;
1121
1122         /* allocation reservation info for delalloc */
1123         /* In case of bigalloc, this refer to clusters rather than blocks */
1124         unsigned int i_reserved_data_blocks;
1125
1126         /* pending cluster reservations for bigalloc file systems */
1127         struct ext4_pending_tree i_pending_tree;
1128
1129         /* on-disk additional length */
1130         __u16 i_extra_isize;
1131
1132         /* Indicate the inline data space. */
1133         u16 i_inline_off;
1134         u16 i_inline_size;
1135
1136 #ifdef CONFIG_QUOTA
1137         /* quota space reservation, managed internally by quota code */
1138         qsize_t i_reserved_quota;
1139 #endif
1140
1141         /* Lock protecting lists below */
1142         spinlock_t i_completed_io_lock;
1143         /*
1144          * Completed IOs that need unwritten extents handling and have
1145          * transaction reserved
1146          */
1147         struct list_head i_rsv_conversion_list;
1148         struct work_struct i_rsv_conversion_work;
1149         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1150
1151         spinlock_t i_block_reservation_lock;
1152
1153         /*
1154          * Transactions that contain inode's metadata needed to complete
1155          * fsync and fdatasync, respectively.
1156          */
1157         tid_t i_sync_tid;
1158         tid_t i_datasync_tid;
1159
1160 #ifdef CONFIG_QUOTA
1161         struct dquot *i_dquot[MAXQUOTAS];
1162 #endif
1163
1164         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1165         __u32 i_csum_seed;
1166
1167         kprojid_t i_projid;
1168 };
1169
1170 /*
1171  * File system states
1172  */
1173 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
1174 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
1175 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
1176 #define EXT4_FC_REPLAY                  0x0020  /* Fast commit replay ongoing */
1177
1178 /*
1179  * Misc. filesystem flags
1180  */
1181 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
1182 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
1183 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
1184
1185 /*
1186  * Mount flags set via mount options or defaults
1187  */
1188 #define EXT4_MOUNT_NO_MBCACHE           0x00001 /* Do not use mbcache */
1189 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
1190 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
1191 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
1192 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
1193 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
1194 #define EXT4_MOUNT_ERRORS_MASK          0x00070
1195 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
1196 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
1197 #ifdef CONFIG_FS_DAX
1198 #define EXT4_MOUNT_DAX_ALWAYS           0x00200 /* Direct Access */
1199 #else
1200 #define EXT4_MOUNT_DAX_ALWAYS           0
1201 #endif
1202 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
1203 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
1204 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
1205 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
1206 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
1207 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
1208 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
1209 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
1210 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
1211 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
1212 #define EXT4_MOUNT_QUOTA                0x40000 /* Some quota option set */
1213 #define EXT4_MOUNT_USRQUOTA             0x80000 /* "old" user quota,
1214                                                  * enable enforcement for hidden
1215                                                  * quota files */
1216 #define EXT4_MOUNT_GRPQUOTA             0x100000 /* "old" group quota, enable
1217                                                   * enforcement for hidden quota
1218                                                   * files */
1219 #define EXT4_MOUNT_PRJQUOTA             0x200000 /* Enable project quota
1220                                                   * enforcement */
1221 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
1222 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
1223 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
1224 #define EXT4_MOUNT_WARN_ON_ERROR        0x2000000 /* Trigger WARN_ON on error */
1225 #define EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS 0x4000000
1226 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
1227 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
1228 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
1229 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
1230 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
1231
1232 /*
1233  * Mount flags set either automatically (could not be set by mount option)
1234  * based on per file system feature or property or in special cases such as
1235  * distinguishing between explicit mount option definition and default.
1236  */
1237 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1238                                                       specified delalloc */
1239 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
1240                                                       size of blocksize * 8
1241                                                       blocks */
1242 #define EXT4_MOUNT2_HURD_COMPAT         0x00000004 /* Support HURD-castrated
1243                                                       file systems */
1244 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM   0x00000008 /* User explicitly
1245                                                 specified journal checksum */
1246
1247 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT 0x00000010 /* Journal fast commit */
1248 #define EXT4_MOUNT2_DAX_NEVER           0x00000020 /* Do not allow Direct Access */
1249 #define EXT4_MOUNT2_DAX_INODE           0x00000040 /* For printing options only */
1250
1251
1252 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1253                                                 ~EXT4_MOUNT_##opt
1254 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1255                                                 EXT4_MOUNT_##opt
1256 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1257                                          EXT4_MOUNT_##opt)
1258
1259 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1260                                                 ~EXT4_MOUNT2_##opt
1261 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1262                                                 EXT4_MOUNT2_##opt
1263 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1264                                          EXT4_MOUNT2_##opt)
1265
1266 #define ext4_test_and_set_bit           __test_and_set_bit_le
1267 #define ext4_set_bit                    __set_bit_le
1268 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1269 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1270 #define ext4_clear_bit                  __clear_bit_le
1271 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1272 #define ext4_test_bit                   test_bit_le
1273 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1274 #define ext4_find_next_bit              find_next_bit_le
1275
1276 extern void ext4_set_bits(void *bm, int cur, int len);
1277
1278 /*
1279  * Maximal mount counts between two filesystem checks
1280  */
1281 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1282 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1283
1284 /*
1285  * Behaviour when detecting errors
1286  */
1287 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1288 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1289 #define EXT4_ERRORS_PANIC               3       /* Panic */
1290 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1291
1292 /* Metadata checksum algorithm codes */
1293 #define EXT4_CRC32C_CHKSUM              1
1294
1295 /*
1296  * Structure of the super block
1297  */
1298 struct ext4_super_block {
1299 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1300         __le32  s_blocks_count_lo;      /* Blocks count */
1301         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1302         __le32  s_free_blocks_count_lo; /* Free blocks count */
1303 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1304         __le32  s_first_data_block;     /* First Data Block */
1305         __le32  s_log_block_size;       /* Block size */
1306         __le32  s_log_cluster_size;     /* Allocation cluster size */
1307 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1308         __le32  s_clusters_per_group;   /* # Clusters per group */
1309         __le32  s_inodes_per_group;     /* # Inodes per group */
1310         __le32  s_mtime;                /* Mount time */
1311 /*30*/  __le32  s_wtime;                /* Write time */
1312         __le16  s_mnt_count;            /* Mount count */
1313         __le16  s_max_mnt_count;        /* Maximal mount count */
1314         __le16  s_magic;                /* Magic signature */
1315         __le16  s_state;                /* File system state */
1316         __le16  s_errors;               /* Behaviour when detecting errors */
1317         __le16  s_minor_rev_level;      /* minor revision level */
1318 /*40*/  __le32  s_lastcheck;            /* time of last check */
1319         __le32  s_checkinterval;        /* max. time between checks */
1320         __le32  s_creator_os;           /* OS */
1321         __le32  s_rev_level;            /* Revision level */
1322 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1323         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1324         /*
1325          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1326          *
1327          * Note: the difference between the compatible feature set and
1328          * the incompatible feature set is that if there is a bit set
1329          * in the incompatible feature set that the kernel doesn't
1330          * know about, it should refuse to mount the filesystem.
1331          *
1332          * e2fsck's requirements are more strict; if it doesn't know
1333          * about a feature in either the compatible or incompatible
1334          * feature set, it must abort and not try to meddle with
1335          * things it doesn't understand...
1336          */
1337         __le32  s_first_ino;            /* First non-reserved inode */
1338         __le16  s_inode_size;           /* size of inode structure */
1339         __le16  s_block_group_nr;       /* block group # of this superblock */
1340         __le32  s_feature_compat;       /* compatible feature set */
1341 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1342         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1343 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1344 /*78*/  char    s_volume_name[16];      /* volume name */
1345 /*88*/  char    s_last_mounted[64] __nonstring; /* directory where last mounted */
1346 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1347         /*
1348          * Performance hints.  Directory preallocation should only
1349          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1350          */
1351         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1352         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1353         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1354         /*
1355          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1356          */
1357 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1358 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1359         __le32  s_journal_dev;          /* device number of journal file */
1360         __le32  s_last_orphan;          /* start of list of inodes to delete */
1361         __le32  s_hash_seed[4];         /* HTREE hash seed */
1362         __u8    s_def_hash_version;     /* Default hash version to use */
1363         __u8    s_jnl_backup_type;
1364         __le16  s_desc_size;            /* size of group descriptor */
1365 /*100*/ __le32  s_default_mount_opts;
1366         __le32  s_first_meta_bg;        /* First metablock block group */
1367         __le32  s_mkfs_time;            /* When the filesystem was created */
1368         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1369         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1370 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1371         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1372         __le32  s_free_blocks_count_hi; /* Free blocks count */
1373         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1374         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1375         __le32  s_flags;                /* Miscellaneous flags */
1376         __le16  s_raid_stride;          /* RAID stride */
1377         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1378         __le64  s_mmp_block;            /* Block for multi-mount protection */
1379         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1380         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1381         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1382         __u8    s_encryption_level;     /* versioning level for encryption */
1383         __u8    s_reserved_pad;         /* Padding to next 32bits */
1384         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1385         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1386         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1387         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1388                                               snapshot's future use */
1389         __le32  s_snapshot_list;        /* inode number of the head of the
1390                                            on-disk snapshot list */
1391 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1392         __le32  s_error_count;          /* number of fs errors */
1393         __le32  s_first_error_time;     /* first time an error happened */
1394         __le32  s_first_error_ino;      /* inode involved in first error */
1395         __le64  s_first_error_block;    /* block involved of first error */
1396         __u8    s_first_error_func[32] __nonstring;     /* function where the error happened */
1397         __le32  s_first_error_line;     /* line number where error happened */
1398         __le32  s_last_error_time;      /* most recent time of an error */
1399         __le32  s_last_error_ino;       /* inode involved in last error */
1400         __le32  s_last_error_line;      /* line number where error happened */
1401         __le64  s_last_error_block;     /* block involved of last error */
1402         __u8    s_last_error_func[32] __nonstring;      /* function where the error happened */
1403 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1404         __u8    s_mount_opts[64];
1405         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1406         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1407         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1408         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
1409         __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
1410         __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
1411         __le32  s_lpf_ino;              /* Location of the lost+found inode */
1412         __le32  s_prj_quota_inum;       /* inode for tracking project quota */
1413         __le32  s_checksum_seed;        /* crc32c(uuid) if csum_seed set */
1414         __u8    s_wtime_hi;
1415         __u8    s_mtime_hi;
1416         __u8    s_mkfs_time_hi;
1417         __u8    s_lastcheck_hi;
1418         __u8    s_first_error_time_hi;
1419         __u8    s_last_error_time_hi;
1420         __u8    s_first_error_errcode;
1421         __u8    s_last_error_errcode;
1422         __le16  s_encoding;             /* Filename charset encoding */
1423         __le16  s_encoding_flags;       /* Filename charset encoding flags */
1424         __le32  s_reserved[95];         /* Padding to the end of the block */
1425         __le32  s_checksum;             /* crc32c(superblock) */
1426 };
1427
1428 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1429
1430 #ifdef __KERNEL__
1431
1432 #ifdef CONFIG_FS_ENCRYPTION
1433 #define DUMMY_ENCRYPTION_ENABLED(sbi) ((sbi)->s_dummy_enc_policy.policy != NULL)
1434 #else
1435 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1436 #endif
1437
1438 /* Number of quota types we support */
1439 #define EXT4_MAXQUOTAS 3
1440
1441 #define EXT4_ENC_UTF8_12_1      1
1442
1443 /*
1444  * fourth extended-fs super-block data in memory
1445  */
1446 struct ext4_sb_info {
1447         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1448         unsigned long s_inodes_per_block;/* Number of inodes per block */
1449         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1450         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1451         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1452         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1453         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1454         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1455         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1456         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1457         unsigned long s_overhead;  /* # of fs overhead clusters */
1458         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1459         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1460         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1461         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1462         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1463         struct buffer_head * __rcu *s_group_desc;
1464         unsigned int s_mount_opt;
1465         unsigned int s_mount_opt2;
1466         unsigned long s_mount_flags;
1467         unsigned int s_def_mount_opt;
1468         ext4_fsblk_t s_sb_block;
1469         atomic64_t s_resv_clusters;
1470         kuid_t s_resuid;
1471         kgid_t s_resgid;
1472         unsigned short s_mount_state;
1473         unsigned short s_pad;
1474         int s_addr_per_block_bits;
1475         int s_desc_per_block_bits;
1476         int s_inode_size;
1477         int s_first_ino;
1478         unsigned int s_inode_readahead_blks;
1479         unsigned int s_inode_goal;
1480         u32 s_hash_seed[4];
1481         int s_def_hash_version;
1482         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1483         struct percpu_counter s_freeclusters_counter;
1484         struct percpu_counter s_freeinodes_counter;
1485         struct percpu_counter s_dirs_counter;
1486         struct percpu_counter s_dirtyclusters_counter;
1487         struct blockgroup_lock *s_blockgroup_lock;
1488         struct proc_dir_entry *s_proc;
1489         struct kobject s_kobj;
1490         struct completion s_kobj_unregister;
1491         struct super_block *s_sb;
1492
1493         /* Journaling */
1494         struct journal_s *s_journal;
1495         struct list_head s_orphan;
1496         struct mutex s_orphan_lock;
1497         unsigned long s_ext4_flags;             /* Ext4 superblock flags */
1498         unsigned long s_commit_interval;
1499         u32 s_max_batch_time;
1500         u32 s_min_batch_time;
1501         struct block_device *s_journal_bdev;
1502 #ifdef CONFIG_QUOTA
1503         /* Names of quota files with journalled quota */
1504         char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1505         int s_jquota_fmt;                       /* Format of quota to use */
1506 #endif
1507         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1508         struct ext4_system_blocks __rcu *s_system_blks;
1509
1510 #ifdef EXTENTS_STATS
1511         /* ext4 extents stats */
1512         unsigned long s_ext_min;
1513         unsigned long s_ext_max;
1514         unsigned long s_depth_max;
1515         spinlock_t s_ext_stats_lock;
1516         unsigned long s_ext_blocks;
1517         unsigned long s_ext_extents;
1518 #endif
1519
1520         /* for buddy allocator */
1521         struct ext4_group_info ** __rcu *s_group_info;
1522         struct inode *s_buddy_cache;
1523         spinlock_t s_md_lock;
1524         unsigned short *s_mb_offsets;
1525         unsigned int *s_mb_maxs;
1526         unsigned int s_group_info_size;
1527         unsigned int s_mb_free_pending;
1528         struct list_head s_freed_data_list;     /* List of blocks to be freed
1529                                                    after commit completed */
1530
1531         /* tunables */
1532         unsigned long s_stripe;
1533         unsigned int s_mb_stream_request;
1534         unsigned int s_mb_max_to_scan;
1535         unsigned int s_mb_min_to_scan;
1536         unsigned int s_mb_stats;
1537         unsigned int s_mb_order2_reqs;
1538         unsigned int s_mb_group_prealloc;
1539         unsigned int s_mb_max_inode_prealloc;
1540         unsigned int s_max_dir_size_kb;
1541         /* where last allocation was done - for stream allocation */
1542         unsigned long s_mb_last_group;
1543         unsigned long s_mb_last_start;
1544         unsigned int s_mb_prefetch;
1545         unsigned int s_mb_prefetch_limit;
1546
1547         /* stats for buddy allocator */
1548         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1549         atomic_t s_bal_success; /* we found long enough chunks */
1550         atomic_t s_bal_allocated;       /* in blocks */
1551         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1552         atomic_t s_bal_goals;   /* goal hits */
1553         atomic_t s_bal_breaks;  /* too long searches */
1554         atomic_t s_bal_2orders; /* 2^order hits */
1555         spinlock_t s_bal_lock;
1556         unsigned long s_mb_buddies_generated;
1557         unsigned long long s_mb_generation_time;
1558         atomic_t s_mb_lost_chunks;
1559         atomic_t s_mb_preallocated;
1560         atomic_t s_mb_discarded;
1561         atomic_t s_lock_busy;
1562
1563         /* locality groups */
1564         struct ext4_locality_group __percpu *s_locality_groups;
1565
1566         /* for write statistics */
1567         unsigned long s_sectors_written_start;
1568         u64 s_kbytes_written;
1569
1570         /* the size of zero-out chunk */
1571         unsigned int s_extent_max_zeroout_kb;
1572
1573         unsigned int s_log_groups_per_flex;
1574         struct flex_groups * __rcu *s_flex_groups;
1575         ext4_group_t s_flex_groups_allocated;
1576
1577         /* workqueue for reserved extent conversions (buffered io) */
1578         struct workqueue_struct *rsv_conversion_wq;
1579
1580         /* timer for periodic error stats printing */
1581         struct timer_list s_err_report;
1582
1583         /* Lazy inode table initialization info */
1584         struct ext4_li_request *s_li_request;
1585         /* Wait multiplier for lazy initialization thread */
1586         unsigned int s_li_wait_mult;
1587
1588         /* Kernel thread for multiple mount protection */
1589         struct task_struct *s_mmp_tsk;
1590
1591         /* record the last minlen when FITRIM is called. */
1592         atomic_t s_last_trim_minblks;
1593
1594         /* Reference to checksum algorithm driver via cryptoapi */
1595         struct crypto_shash *s_chksum_driver;
1596
1597         /* Precomputed FS UUID checksum for seeding other checksums */
1598         __u32 s_csum_seed;
1599
1600         /* Reclaim extents from extent status tree */
1601         struct shrinker s_es_shrinker;
1602         struct list_head s_es_list;     /* List of inodes with reclaimable extents */
1603         long s_es_nr_inode;
1604         struct ext4_es_stats s_es_stats;
1605         struct mb_cache *s_ea_block_cache;
1606         struct mb_cache *s_ea_inode_cache;
1607         spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1608
1609         /* Ratelimit ext4 messages. */
1610         struct ratelimit_state s_err_ratelimit_state;
1611         struct ratelimit_state s_warning_ratelimit_state;
1612         struct ratelimit_state s_msg_ratelimit_state;
1613         atomic_t s_warning_count;
1614         atomic_t s_msg_count;
1615
1616         /* Encryption policy for '-o test_dummy_encryption' */
1617         struct fscrypt_dummy_policy s_dummy_enc_policy;
1618
1619         /*
1620          * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1621          * or EXTENTS flag.
1622          */
1623         struct percpu_rw_semaphore s_writepages_rwsem;
1624         struct dax_device *s_daxdev;
1625 #ifdef CONFIG_EXT4_DEBUG
1626         unsigned long s_simulate_fail;
1627 #endif
1628         /* Record the errseq of the backing block device */
1629         errseq_t s_bdev_wb_err;
1630         spinlock_t s_bdev_wb_lock;
1631
1632         /* Information about errors that happened during this mount */
1633         spinlock_t s_error_lock;
1634         int s_add_error_count;
1635         int s_first_error_code;
1636         __u32 s_first_error_line;
1637         __u32 s_first_error_ino;
1638         __u64 s_first_error_block;
1639         const char *s_first_error_func;
1640         time64_t s_first_error_time;
1641         int s_last_error_code;
1642         __u32 s_last_error_line;
1643         __u32 s_last_error_ino;
1644         __u64 s_last_error_block;
1645         const char *s_last_error_func;
1646         time64_t s_last_error_time;
1647         /*
1648          * If we are in a context where we cannot update error information in
1649          * the on-disk superblock, we queue this work to do it.
1650          */
1651         struct work_struct s_error_work;
1652
1653         /* Ext4 fast commit stuff */
1654         atomic_t s_fc_subtid;
1655         atomic_t s_fc_ineligible_updates;
1656         /*
1657          * After commit starts, the main queue gets locked, and the further
1658          * updates get added in the staging queue.
1659          */
1660 #define FC_Q_MAIN       0
1661 #define FC_Q_STAGING    1
1662         struct list_head s_fc_q[2];     /* Inodes staged for fast commit
1663                                          * that have data changes in them.
1664                                          */
1665         struct list_head s_fc_dentry_q[2];      /* directory entry updates */
1666         unsigned int s_fc_bytes;
1667         /*
1668          * Main fast commit lock. This lock protects accesses to the
1669          * following fields:
1670          * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1671          */
1672         spinlock_t s_fc_lock;
1673         struct buffer_head *s_fc_bh;
1674         struct ext4_fc_stats s_fc_stats;
1675         u64 s_fc_avg_commit_time;
1676 #ifdef CONFIG_EXT4_DEBUG
1677         int s_fc_debug_max_replay;
1678 #endif
1679         struct ext4_fc_replay_state s_fc_replay_state;
1680 };
1681
1682 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1683 {
1684         return sb->s_fs_info;
1685 }
1686 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1687 {
1688         return container_of(inode, struct ext4_inode_info, vfs_inode);
1689 }
1690
1691 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1692 {
1693         return ino == EXT4_ROOT_INO ||
1694                 (ino >= EXT4_FIRST_INO(sb) &&
1695                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1696 }
1697
1698 /*
1699  * Returns: sbi->field[index]
1700  * Used to access an array element from the following sbi fields which require
1701  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1702  * - s_group_desc
1703  * - s_group_info
1704  * - s_flex_group
1705  */
1706 #define sbi_array_rcu_deref(sbi, field, index)                             \
1707 ({                                                                         \
1708         typeof(*((sbi)->field)) _v;                                        \
1709         rcu_read_lock();                                                   \
1710         _v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];          \
1711         rcu_read_unlock();                                                 \
1712         _v;                                                                \
1713 })
1714
1715 /*
1716  * run-time mount flags
1717  */
1718 enum {
1719         EXT4_MF_MNTDIR_SAMPLED,
1720         EXT4_MF_FS_ABORTED,     /* Fatal error detected */
1721         EXT4_MF_FC_INELIGIBLE,  /* Fast commit ineligible */
1722         EXT4_MF_FC_COMMITTING   /* File system underoing a fast
1723                                  * commit.
1724                                  */
1725 };
1726
1727 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
1728 {
1729         set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1730 }
1731
1732 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
1733 {
1734         clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1735 }
1736
1737 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
1738 {
1739         return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1740 }
1741
1742
1743 /*
1744  * Simulate_fail codes
1745  */
1746 #define EXT4_SIM_BBITMAP_EIO    1
1747 #define EXT4_SIM_BBITMAP_CRC    2
1748 #define EXT4_SIM_IBITMAP_EIO    3
1749 #define EXT4_SIM_IBITMAP_CRC    4
1750 #define EXT4_SIM_INODE_EIO      5
1751 #define EXT4_SIM_INODE_CRC      6
1752 #define EXT4_SIM_DIRBLOCK_EIO   7
1753 #define EXT4_SIM_DIRBLOCK_CRC   8
1754
1755 static inline bool ext4_simulate_fail(struct super_block *sb,
1756                                      unsigned long code)
1757 {
1758 #ifdef CONFIG_EXT4_DEBUG
1759         struct ext4_sb_info *sbi = EXT4_SB(sb);
1760
1761         if (unlikely(sbi->s_simulate_fail == code)) {
1762                 sbi->s_simulate_fail = 0;
1763                 return true;
1764         }
1765 #endif
1766         return false;
1767 }
1768
1769 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1770                                          struct buffer_head *bh,
1771                                          unsigned long code)
1772 {
1773         if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1774                 clear_buffer_uptodate(bh);
1775 }
1776
1777 /*
1778  * Error number codes for s_{first,last}_error_errno
1779  *
1780  * Linux errno numbers are architecture specific, so we need to translate
1781  * them into something which is architecture independent.   We don't define
1782  * codes for all errno's; just the ones which are most likely to be the cause
1783  * of an ext4_error() call.
1784  */
1785 #define EXT4_ERR_UNKNOWN         1
1786 #define EXT4_ERR_EIO             2
1787 #define EXT4_ERR_ENOMEM          3
1788 #define EXT4_ERR_EFSBADCRC       4
1789 #define EXT4_ERR_EFSCORRUPTED    5
1790 #define EXT4_ERR_ENOSPC          6
1791 #define EXT4_ERR_ENOKEY          7
1792 #define EXT4_ERR_EROFS           8
1793 #define EXT4_ERR_EFBIG           9
1794 #define EXT4_ERR_EEXIST         10
1795 #define EXT4_ERR_ERANGE         11
1796 #define EXT4_ERR_EOVERFLOW      12
1797 #define EXT4_ERR_EBUSY          13
1798 #define EXT4_ERR_ENOTDIR        14
1799 #define EXT4_ERR_ENOTEMPTY      15
1800 #define EXT4_ERR_ESHUTDOWN      16
1801 #define EXT4_ERR_EFAULT         17
1802
1803 /*
1804  * Inode dynamic state flags
1805  */
1806 enum {
1807         EXT4_STATE_JDATA,               /* journaled data exists */
1808         EXT4_STATE_NEW,                 /* inode is newly created */
1809         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1810         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1811         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1812         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1813         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1814         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1815         EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
1816         EXT4_STATE_LUSTRE_EA_INODE,     /* Lustre-style ea_inode */
1817         EXT4_STATE_VERITY_IN_PROGRESS,  /* building fs-verity Merkle tree */
1818         EXT4_STATE_FC_COMMITTING,       /* Fast commit ongoing */
1819 };
1820
1821 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1822 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1823 {                                                                       \
1824         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1825 }                                                                       \
1826 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1827 {                                                                       \
1828         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1829 }                                                                       \
1830 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1831 {                                                                       \
1832         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1833 }
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_flag(struct inode *inode, int bit);
1838 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1839 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1840 EXT4_INODE_BIT_FNS(flag, flags, 0)
1841
1842 /* Add these declarations here only so that these functions can be
1843  * found by name.  Otherwise, they are very hard to locate. */
1844 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1845 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1846 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1847 #if (BITS_PER_LONG < 64)
1848 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1849
1850 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1851 {
1852         (ei)->i_state_flags = 0;
1853 }
1854 #else
1855 EXT4_INODE_BIT_FNS(state, flags, 32)
1856
1857 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1858 {
1859         /* We depend on the fact that callers will set i_flags */
1860 }
1861 #endif
1862 #else
1863 /* Assume that user mode programs are passing in an ext4fs superblock, not
1864  * a kernel struct super_block.  This will allow us to call the feature-test
1865  * macros from user land. */
1866 #define EXT4_SB(sb)     (sb)
1867 #endif
1868
1869 static inline bool ext4_verity_in_progress(struct inode *inode)
1870 {
1871         return IS_ENABLED(CONFIG_FS_VERITY) &&
1872                ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1873 }
1874
1875 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1876
1877 /*
1878  * Codes for operating systems
1879  */
1880 #define EXT4_OS_LINUX           0
1881 #define EXT4_OS_HURD            1
1882 #define EXT4_OS_MASIX           2
1883 #define EXT4_OS_FREEBSD         3
1884 #define EXT4_OS_LITES           4
1885
1886 /*
1887  * Revision levels
1888  */
1889 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1890 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1891
1892 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1893
1894 #define EXT4_GOOD_OLD_INODE_SIZE 128
1895
1896 #define EXT4_EXTRA_TIMESTAMP_MAX        (((s64)1 << 34) - 1  + S32_MIN)
1897 #define EXT4_NON_EXTRA_TIMESTAMP_MAX    S32_MAX
1898 #define EXT4_TIMESTAMP_MIN              S32_MIN
1899
1900 /*
1901  * Feature set definitions
1902  */
1903
1904 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1905 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1906 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1907 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1908 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1909 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1910 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2       0x0200
1911 /*
1912  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
1913  * incompatible only if fast commit blocks are present in the FS. Since we
1914  * clear the journal (and thus the fast commit blocks), we don't mark FS as
1915  * incompatible. We also have a JBD2 incompat feature, which gets set when
1916  * there are fast commit blocks present in the journal.
1917  */
1918 #define EXT4_FEATURE_COMPAT_FAST_COMMIT         0x0400
1919 #define EXT4_FEATURE_COMPAT_STABLE_INODES       0x0800
1920
1921 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1922 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1923 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1924 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1925 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1926 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1927 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1928 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1929 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1930 /*
1931  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1932  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1933  * all other data structures' checksums.  However, the METADATA_CSUM and
1934  * GDT_CSUM bits are mutually exclusive.
1935  */
1936 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1937 #define EXT4_FEATURE_RO_COMPAT_READONLY         0x1000
1938 #define EXT4_FEATURE_RO_COMPAT_PROJECT          0x2000
1939 #define EXT4_FEATURE_RO_COMPAT_VERITY           0x8000
1940
1941 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1942 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1943 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1944 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1945 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1946 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1947 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1948 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1949 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1950 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1951 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1952 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED         0x2000
1953 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1954 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1955 #define EXT4_FEATURE_INCOMPAT_ENCRYPT           0x10000
1956 #define EXT4_FEATURE_INCOMPAT_CASEFOLD          0x20000
1957
1958 extern void ext4_update_dynamic_rev(struct super_block *sb);
1959
1960 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1961 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1962 { \
1963         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1964                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1965 } \
1966 static inline void ext4_set_feature_##name(struct super_block *sb) \
1967 { \
1968         ext4_update_dynamic_rev(sb); \
1969         EXT4_SB(sb)->s_es->s_feature_compat |= \
1970                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1971 } \
1972 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1973 { \
1974         EXT4_SB(sb)->s_es->s_feature_compat &= \
1975                 ~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1976 }
1977
1978 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1979 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1980 { \
1981         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1982                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1983 } \
1984 static inline void ext4_set_feature_##name(struct super_block *sb) \
1985 { \
1986         ext4_update_dynamic_rev(sb); \
1987         EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1988                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1989 } \
1990 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1991 { \
1992         EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1993                 ~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1994 }
1995
1996 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1997 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1998 { \
1999         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2000                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
2001 } \
2002 static inline void ext4_set_feature_##name(struct super_block *sb) \
2003 { \
2004         ext4_update_dynamic_rev(sb); \
2005         EXT4_SB(sb)->s_es->s_feature_incompat |= \
2006                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2007 } \
2008 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2009 { \
2010         EXT4_SB(sb)->s_es->s_feature_incompat &= \
2011                 ~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2012 }
2013
2014 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,         DIR_PREALLOC)
2015 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,        IMAGIC_INODES)
2016 EXT4_FEATURE_COMPAT_FUNCS(journal,              HAS_JOURNAL)
2017 EXT4_FEATURE_COMPAT_FUNCS(xattr,                EXT_ATTR)
2018 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,         RESIZE_INODE)
2019 EXT4_FEATURE_COMPAT_FUNCS(dir_index,            DIR_INDEX)
2020 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,        SPARSE_SUPER2)
2021 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,          FAST_COMMIT)
2022 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,        STABLE_INODES)
2023
2024 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,      SPARSE_SUPER)
2025 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,        LARGE_FILE)
2026 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,         BTREE_DIR)
2027 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,         HUGE_FILE)
2028 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,          GDT_CSUM)
2029 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,         DIR_NLINK)
2030 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,       EXTRA_ISIZE)
2031 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,             QUOTA)
2032 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,          BIGALLOC)
2033 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,     METADATA_CSUM)
2034 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,          READONLY)
2035 EXT4_FEATURE_RO_COMPAT_FUNCS(project,           PROJECT)
2036 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,            VERITY)
2037
2038 EXT4_FEATURE_INCOMPAT_FUNCS(compression,        COMPRESSION)
2039 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,           FILETYPE)
2040 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,     RECOVER)
2041 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,        JOURNAL_DEV)
2042 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,            META_BG)
2043 EXT4_FEATURE_INCOMPAT_FUNCS(extents,            EXTENTS)
2044 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,              64BIT)
2045 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,                MMP)
2046 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,            FLEX_BG)
2047 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,           EA_INODE)
2048 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,            DIRDATA)
2049 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,          CSUM_SEED)
2050 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,           LARGEDIR)
2051 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,        INLINE_DATA)
2052 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,            ENCRYPT)
2053 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,           CASEFOLD)
2054
2055 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2056 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2057                                          EXT4_FEATURE_INCOMPAT_META_BG)
2058 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2059                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2060                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2061
2062 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2063 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2064                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
2065                                          EXT4_FEATURE_INCOMPAT_META_BG)
2066 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2067                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2068                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2069
2070 #define EXT4_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
2071 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
2072                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
2073                                          EXT4_FEATURE_INCOMPAT_META_BG| \
2074                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
2075                                          EXT4_FEATURE_INCOMPAT_64BIT| \
2076                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2077                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
2078                                          EXT4_FEATURE_INCOMPAT_MMP | \
2079                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2080                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2081                                          EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2082                                          EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2083                                          EXT4_FEATURE_INCOMPAT_LARGEDIR)
2084 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2085                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2086                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2087                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2088                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2089                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2090                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2091                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2092                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2093                                          EXT4_FEATURE_RO_COMPAT_QUOTA |\
2094                                          EXT4_FEATURE_RO_COMPAT_PROJECT |\
2095                                          EXT4_FEATURE_RO_COMPAT_VERITY)
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 /*
2132  * Superblock flags
2133  */
2134 #define EXT4_FLAGS_RESIZING     0
2135 #define EXT4_FLAGS_SHUTDOWN     1
2136 #define EXT4_FLAGS_BDEV_IS_DAX  2
2137
2138 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2139 {
2140         return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2141 }
2142
2143
2144 /*
2145  * Default values for user and/or group using reserved blocks
2146  */
2147 #define EXT4_DEF_RESUID         0
2148 #define EXT4_DEF_RESGID         0
2149
2150 /*
2151  * Default project ID
2152  */
2153 #define EXT4_DEF_PROJID         0
2154
2155 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
2156
2157 /*
2158  * Default mount options
2159  */
2160 #define EXT4_DEFM_DEBUG         0x0001
2161 #define EXT4_DEFM_BSDGROUPS     0x0002
2162 #define EXT4_DEFM_XATTR_USER    0x0004
2163 #define EXT4_DEFM_ACL           0x0008
2164 #define EXT4_DEFM_UID16         0x0010
2165 #define EXT4_DEFM_JMODE         0x0060
2166 #define EXT4_DEFM_JMODE_DATA    0x0020
2167 #define EXT4_DEFM_JMODE_ORDERED 0x0040
2168 #define EXT4_DEFM_JMODE_WBACK   0x0060
2169 #define EXT4_DEFM_NOBARRIER     0x0100
2170 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2171 #define EXT4_DEFM_DISCARD       0x0400
2172 #define EXT4_DEFM_NODELALLOC    0x0800
2173
2174 /*
2175  * Default journal batch times
2176  */
2177 #define EXT4_DEF_MIN_BATCH_TIME 0
2178 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
2179
2180 /*
2181  * Minimum number of groups in a flexgroup before we separate out
2182  * directories into the first block group of a flexgroup
2183  */
2184 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
2185
2186 /*
2187  * Structure of a directory entry
2188  */
2189 #define EXT4_NAME_LEN 255
2190
2191 struct ext4_dir_entry {
2192         __le32  inode;                  /* Inode number */
2193         __le16  rec_len;                /* Directory entry length */
2194         __le16  name_len;               /* Name length */
2195         char    name[EXT4_NAME_LEN];    /* File name */
2196 };
2197
2198 /*
2199  * The new version of the directory entry.  Since EXT4 structures are
2200  * stored in intel byte order, and the name_len field could never be
2201  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2202  * file_type field.
2203  */
2204 struct ext4_dir_entry_2 {
2205         __le32  inode;                  /* Inode number */
2206         __le16  rec_len;                /* Directory entry length */
2207         __u8    name_len;               /* Name length */
2208         __u8    file_type;              /* See file type macros EXT4_FT_* below */
2209         char    name[EXT4_NAME_LEN];    /* File name */
2210 };
2211
2212 /*
2213  * This is a bogus directory entry at the end of each leaf block that
2214  * records checksums.
2215  */
2216 struct ext4_dir_entry_tail {
2217         __le32  det_reserved_zero1;     /* Pretend to be unused */
2218         __le16  det_rec_len;            /* 12 */
2219         __u8    det_reserved_zero2;     /* Zero name length */
2220         __u8    det_reserved_ft;        /* 0xDE, fake file type */
2221         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
2222 };
2223
2224 #define EXT4_DIRENT_TAIL(block, blocksize) \
2225         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2226                                         ((blocksize) - \
2227                                          sizeof(struct ext4_dir_entry_tail))))
2228
2229 /*
2230  * Ext4 directory file types.  Only the low 3 bits are used.  The
2231  * other bits are reserved for now.
2232  */
2233 #define EXT4_FT_UNKNOWN         0
2234 #define EXT4_FT_REG_FILE        1
2235 #define EXT4_FT_DIR             2
2236 #define EXT4_FT_CHRDEV          3
2237 #define EXT4_FT_BLKDEV          4
2238 #define EXT4_FT_FIFO            5
2239 #define EXT4_FT_SOCK            6
2240 #define EXT4_FT_SYMLINK         7
2241
2242 #define EXT4_FT_MAX             8
2243
2244 #define EXT4_FT_DIR_CSUM        0xDE
2245
2246 /*
2247  * EXT4_DIR_PAD defines the directory entries boundaries
2248  *
2249  * NOTE: It must be a multiple of 4
2250  */
2251 #define EXT4_DIR_PAD                    4
2252 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
2253 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
2254                                          ~EXT4_DIR_ROUND)
2255 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
2256
2257 /*
2258  * If we ever get support for fs block sizes > page_size, we'll need
2259  * to remove the #if statements in the next two functions...
2260  */
2261 static inline unsigned int
2262 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2263 {
2264         unsigned len = le16_to_cpu(dlen);
2265
2266 #if (PAGE_SIZE >= 65536)
2267         if (len == EXT4_MAX_REC_LEN || len == 0)
2268                 return blocksize;
2269         return (len & 65532) | ((len & 3) << 16);
2270 #else
2271         return len;
2272 #endif
2273 }
2274
2275 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2276 {
2277         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2278                 BUG();
2279 #if (PAGE_SIZE >= 65536)
2280         if (len < 65536)
2281                 return cpu_to_le16(len);
2282         if (len == blocksize) {
2283                 if (blocksize == 65536)
2284                         return cpu_to_le16(EXT4_MAX_REC_LEN);
2285                 else
2286                         return cpu_to_le16(0);
2287         }
2288         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2289 #else
2290         return cpu_to_le16(len);
2291 #endif
2292 }
2293
2294 /*
2295  * Hash Tree Directory indexing
2296  * (c) Daniel Phillips, 2001
2297  */
2298
2299 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2300                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2301 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2302                     !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2303 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2304
2305 /* Legal values for the dx_root hash_version field: */
2306
2307 #define DX_HASH_LEGACY                  0
2308 #define DX_HASH_HALF_MD4                1
2309 #define DX_HASH_TEA                     2
2310 #define DX_HASH_LEGACY_UNSIGNED         3
2311 #define DX_HASH_HALF_MD4_UNSIGNED       4
2312 #define DX_HASH_TEA_UNSIGNED            5
2313
2314 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2315                               const void *address, unsigned int length)
2316 {
2317         struct {
2318                 struct shash_desc shash;
2319                 char ctx[4];
2320         } desc;
2321
2322         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2323
2324         desc.shash.tfm = sbi->s_chksum_driver;
2325         *(u32 *)desc.ctx = crc;
2326
2327         BUG_ON(crypto_shash_update(&desc.shash, address, length));
2328
2329         return *(u32 *)desc.ctx;
2330 }
2331
2332 #ifdef __KERNEL__
2333
2334 /* hash info structure used by the directory hash */
2335 struct dx_hash_info
2336 {
2337         u32             hash;
2338         u32             minor_hash;
2339         int             hash_version;
2340         u32             *seed;
2341 };
2342
2343
2344 /* 32 and 64 bit signed EOF for dx directories */
2345 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2346 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2347
2348
2349 /*
2350  * Control parameters used by ext4_htree_next_block
2351  */
2352 #define HASH_NB_ALWAYS          1
2353
2354 struct ext4_filename {
2355         const struct qstr *usr_fname;
2356         struct fscrypt_str disk_name;
2357         struct dx_hash_info hinfo;
2358 #ifdef CONFIG_FS_ENCRYPTION
2359         struct fscrypt_str crypto_buf;
2360 #endif
2361 #ifdef CONFIG_UNICODE
2362         struct fscrypt_str cf_name;
2363 #endif
2364 };
2365
2366 #define fname_name(p) ((p)->disk_name.name)
2367 #define fname_len(p)  ((p)->disk_name.len)
2368
2369 /*
2370  * Describe an inode's exact location on disk and in memory
2371  */
2372 struct ext4_iloc
2373 {
2374         struct buffer_head *bh;
2375         unsigned long offset;
2376         ext4_group_t block_group;
2377 };
2378
2379 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2380 {
2381         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2382 }
2383
2384 static inline bool ext4_is_quota_file(struct inode *inode)
2385 {
2386         return IS_NOQUOTA(inode) &&
2387                !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2388 }
2389
2390 /*
2391  * This structure is stuffed into the struct file's private_data field
2392  * for directories.  It is where we put information so that we can do
2393  * readdir operations in hash tree order.
2394  */
2395 struct dir_private_info {
2396         struct rb_root  root;
2397         struct rb_node  *curr_node;
2398         struct fname    *extra_fname;
2399         loff_t          last_pos;
2400         __u32           curr_hash;
2401         __u32           curr_minor_hash;
2402         __u32           next_hash;
2403 };
2404
2405 /* calculate the first block number of the group */
2406 static inline ext4_fsblk_t
2407 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2408 {
2409         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2410                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2411 }
2412
2413 /*
2414  * Special error return code only used by dx_probe() and its callers.
2415  */
2416 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
2417
2418 /* htree levels for ext4 */
2419 #define EXT4_HTREE_LEVEL_COMPAT 2
2420 #define EXT4_HTREE_LEVEL        3
2421
2422 static inline int ext4_dir_htree_level(struct super_block *sb)
2423 {
2424         return ext4_has_feature_largedir(sb) ?
2425                 EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2426 }
2427
2428 /*
2429  * Timeout and state flag for lazy initialization inode thread.
2430  */
2431 #define EXT4_DEF_LI_WAIT_MULT                   10
2432 #define EXT4_DEF_LI_MAX_START_DELAY             5
2433 #define EXT4_LAZYINIT_QUIT                      0x0001
2434 #define EXT4_LAZYINIT_RUNNING                   0x0002
2435
2436 /*
2437  * Lazy inode table initialization info
2438  */
2439 struct ext4_lazy_init {
2440         unsigned long           li_state;
2441         struct list_head        li_request_list;
2442         struct mutex            li_list_mtx;
2443 };
2444
2445 enum ext4_li_mode {
2446         EXT4_LI_MODE_PREFETCH_BBITMAP,
2447         EXT4_LI_MODE_ITABLE,
2448 };
2449
2450 struct ext4_li_request {
2451         struct super_block      *lr_super;
2452         enum ext4_li_mode       lr_mode;
2453         ext4_group_t            lr_first_not_zeroed;
2454         ext4_group_t            lr_next_group;
2455         struct list_head        lr_request;
2456         unsigned long           lr_next_sched;
2457         unsigned long           lr_timeout;
2458 };
2459
2460 struct ext4_features {
2461         struct kobject f_kobj;
2462         struct completion f_kobj_unregister;
2463 };
2464
2465 /*
2466  * This structure will be used for multiple mount protection. It will be
2467  * written into the block number saved in the s_mmp_block field in the
2468  * superblock. Programs that check MMP should assume that if
2469  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2470  * to use the filesystem, regardless of how old the timestamp is.
2471  */
2472 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2473 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2474 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2475 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2476
2477 struct mmp_struct {
2478         __le32  mmp_magic;              /* Magic number for MMP */
2479         __le32  mmp_seq;                /* Sequence no. updated periodically */
2480
2481         /*
2482          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2483          * purposes and do not affect the correctness of the algorithm
2484          */
2485         __le64  mmp_time;               /* Time last updated */
2486         char    mmp_nodename[64];       /* Node which last updated MMP block */
2487         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
2488
2489         /*
2490          * mmp_check_interval is used to verify if the MMP block has been
2491          * updated on the block device. The value is updated based on the
2492          * maximum time to write the MMP block during an update cycle.
2493          */
2494         __le16  mmp_check_interval;
2495
2496         __le16  mmp_pad1;
2497         __le32  mmp_pad2[226];
2498         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
2499 };
2500
2501 /* arguments passed to the mmp thread */
2502 struct mmpd_data {
2503         struct buffer_head *bh; /* bh from initial read_mmp_block() */
2504         struct super_block *sb;  /* super block of the fs */
2505 };
2506
2507 /*
2508  * Check interval multiplier
2509  * The MMP block is written every update interval and initially checked every
2510  * update interval x the multiplier (the value is then adapted based on the
2511  * write latency). The reason is that writes can be delayed under load and we
2512  * don't want readers to incorrectly assume that the filesystem is no longer
2513  * in use.
2514  */
2515 #define EXT4_MMP_CHECK_MULT             2UL
2516
2517 /*
2518  * Minimum interval for MMP checking in seconds.
2519  */
2520 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
2521
2522 /*
2523  * Maximum interval for MMP checking in seconds.
2524  */
2525 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
2526
2527 /*
2528  * Function prototypes
2529  */
2530
2531 /*
2532  * Ok, these declarations are also in <linux/kernel.h> but none of the
2533  * ext4 source programs needs to include it so they are duplicated here.
2534  */
2535 # define NORET_TYPE     /**/
2536 # define ATTRIB_NORET   __attribute__((noreturn))
2537 # define NORET_AND      noreturn,
2538
2539 /* bitmap.c */
2540 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2541 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2542                                 struct ext4_group_desc *gdp,
2543                                 struct buffer_head *bh, int sz);
2544 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2545                                   struct ext4_group_desc *gdp,
2546                                   struct buffer_head *bh, int sz);
2547 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2548                                 struct ext4_group_desc *gdp,
2549                                 struct buffer_head *bh);
2550 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2551                                   struct ext4_group_desc *gdp,
2552                                   struct buffer_head *bh);
2553
2554 /* balloc.c */
2555 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2556                                          ext4_fsblk_t blocknr,
2557                                          ext4_group_t *blockgrpp,
2558                                          ext4_grpblk_t *offsetp);
2559 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2560                                           ext4_fsblk_t block);
2561
2562 extern unsigned int ext4_block_group(struct super_block *sb,
2563                         ext4_fsblk_t blocknr);
2564 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2565                         ext4_fsblk_t blocknr);
2566 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2567 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2568                         ext4_group_t group);
2569 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2570                                          ext4_fsblk_t goal,
2571                                          unsigned int flags,
2572                                          unsigned long *count,
2573                                          int *errp);
2574 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2575                                     s64 nclusters, unsigned int flags);
2576 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2577 extern void ext4_check_blocks_bitmap(struct super_block *);
2578 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2579                                                     ext4_group_t block_group,
2580                                                     struct buffer_head ** bh);
2581 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2582
2583 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2584                                                 ext4_group_t block_group,
2585                                                 bool ignore_locked);
2586 extern int ext4_wait_block_bitmap(struct super_block *sb,
2587                                   ext4_group_t block_group,
2588                                   struct buffer_head *bh);
2589 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2590                                                   ext4_group_t block_group);
2591 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2592                                               ext4_group_t block_group,
2593                                               struct ext4_group_desc *gdp);
2594 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2595
2596 #ifdef CONFIG_UNICODE
2597 extern void ext4_fname_setup_ci_filename(struct inode *dir,
2598                                          const struct qstr *iname,
2599                                          struct fscrypt_str *fname);
2600 #endif
2601
2602 #ifdef CONFIG_FS_ENCRYPTION
2603 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2604                                                 const struct fscrypt_name *src)
2605 {
2606         memset(dst, 0, sizeof(*dst));
2607
2608         dst->usr_fname = src->usr_fname;
2609         dst->disk_name = src->disk_name;
2610         dst->hinfo.hash = src->hash;
2611         dst->hinfo.minor_hash = src->minor_hash;
2612         dst->crypto_buf = src->crypto_buf;
2613 }
2614
2615 static inline int ext4_fname_setup_filename(struct inode *dir,
2616                                             const struct qstr *iname,
2617                                             int lookup,
2618                                             struct ext4_filename *fname)
2619 {
2620         struct fscrypt_name name;
2621         int err;
2622
2623         err = fscrypt_setup_filename(dir, iname, lookup, &name);
2624         if (err)
2625                 return err;
2626
2627         ext4_fname_from_fscrypt_name(fname, &name);
2628
2629 #ifdef CONFIG_UNICODE
2630         ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2631 #endif
2632         return 0;
2633 }
2634
2635 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2636                                             struct dentry *dentry,
2637                                             struct ext4_filename *fname)
2638 {
2639         struct fscrypt_name name;
2640         int err;
2641
2642         err = fscrypt_prepare_lookup(dir, dentry, &name);
2643         if (err)
2644                 return err;
2645
2646         ext4_fname_from_fscrypt_name(fname, &name);
2647
2648 #ifdef CONFIG_UNICODE
2649         ext4_fname_setup_ci_filename(dir, &dentry->d_name, &fname->cf_name);
2650 #endif
2651         return 0;
2652 }
2653
2654 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2655 {
2656         struct fscrypt_name name;
2657
2658         name.crypto_buf = fname->crypto_buf;
2659         fscrypt_free_filename(&name);
2660
2661         fname->crypto_buf.name = NULL;
2662         fname->usr_fname = NULL;
2663         fname->disk_name.name = NULL;
2664
2665 #ifdef CONFIG_UNICODE
2666         kfree(fname->cf_name.name);
2667         fname->cf_name.name = NULL;
2668 #endif
2669 }
2670 #else /* !CONFIG_FS_ENCRYPTION */
2671 static inline int ext4_fname_setup_filename(struct inode *dir,
2672                                             const struct qstr *iname,
2673                                             int lookup,
2674                                             struct ext4_filename *fname)
2675 {
2676         fname->usr_fname = iname;
2677         fname->disk_name.name = (unsigned char *) iname->name;
2678         fname->disk_name.len = iname->len;
2679
2680 #ifdef CONFIG_UNICODE
2681         ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2682 #endif
2683
2684         return 0;
2685 }
2686
2687 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2688                                             struct dentry *dentry,
2689                                             struct ext4_filename *fname)
2690 {
2691         return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2692 }
2693
2694 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2695 {
2696 #ifdef CONFIG_UNICODE
2697         kfree(fname->cf_name.name);
2698         fname->cf_name.name = NULL;
2699 #endif
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 *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(handle_t *, struct inode *, umode_t,
2759                                       const struct qstr *qstr, __u32 goal,
2760                                       uid_t *owner, __u32 i_flags,
2761                                       int handle_type, unsigned int line_no,
2762                                       int nblocks);
2763
2764 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2765         __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2766                          i_flags, 0, 0, 0)
2767 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2768                                     type, nblocks)                  \
2769         __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2770                          0, (type), __LINE__, (nblocks))
2771
2772
2773 extern void ext4_free_inode(handle_t *, struct inode *);
2774 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2775 extern unsigned long ext4_count_free_inodes(struct super_block *);
2776 extern unsigned long ext4_count_dirs(struct super_block *);
2777 extern void ext4_check_inodes_bitmap(struct super_block *);
2778 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2779 extern int ext4_init_inode_table(struct super_block *sb,
2780                                  ext4_group_t group, int barrier);
2781 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2782
2783 /* fast_commit.c */
2784 int ext4_fc_info_show(struct seq_file *seq, void *v);
2785 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2786 void ext4_fc_init_inode(struct inode *inode);
2787 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
2788                          ext4_lblk_t end);
2789 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
2790         struct dentry *dentry);
2791 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
2792         struct dentry *dentry);
2793 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
2794 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
2795 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
2796 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
2797 void ext4_fc_mark_ineligible(struct super_block *sb, int reason);
2798 void ext4_fc_start_ineligible(struct super_block *sb, int reason);
2799 void ext4_fc_stop_ineligible(struct super_block *sb);
2800 void ext4_fc_start_update(struct inode *inode);
2801 void ext4_fc_stop_update(struct inode *inode);
2802 void ext4_fc_del(struct inode *inode);
2803 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2804 void ext4_fc_replay_cleanup(struct super_block *sb);
2805 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2806 int __init ext4_fc_init_dentry_cache(void);
2807
2808 /* mballoc.c */
2809 extern const struct seq_operations ext4_mb_seq_groups_ops;
2810 extern long ext4_mb_stats;
2811 extern long ext4_mb_max_to_scan;
2812 extern int ext4_mb_init(struct super_block *);
2813 extern int ext4_mb_release(struct super_block *);
2814 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2815                                 struct ext4_allocation_request *, int *);
2816 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2817 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2818 extern int __init ext4_init_mballoc(void);
2819 extern void ext4_exit_mballoc(void);
2820 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2821                                      ext4_group_t group,
2822                                      unsigned int nr, int *cnt);
2823 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2824                                   unsigned int nr);
2825
2826 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2827                              struct buffer_head *bh, ext4_fsblk_t block,
2828                              unsigned long count, int flags);
2829 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2830                                    ext4_group_t ngroups);
2831 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2832                 ext4_group_t i, struct ext4_group_desc *desc);
2833 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2834                                 ext4_fsblk_t block, unsigned long count);
2835 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2836 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2837 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2838                        int len, int state);
2839
2840 /* inode.c */
2841 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2842                          struct ext4_inode_info *ei);
2843 int ext4_inode_is_fast_symlink(struct inode *inode);
2844 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2845 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2846 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2847                      bool wait, struct buffer_head **bhs);
2848 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2849                              struct buffer_head *bh_result, int create);
2850 int ext4_get_block(struct inode *inode, sector_t iblock,
2851                    struct buffer_head *bh_result, int create);
2852 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2853                            struct buffer_head *bh, int create);
2854 int ext4_walk_page_buffers(handle_t *handle,
2855                            struct buffer_head *head,
2856                            unsigned from,
2857                            unsigned to,
2858                            int *partial,
2859                            int (*fn)(handle_t *handle,
2860                                      struct buffer_head *bh));
2861 int do_journal_get_write_access(handle_t *handle,
2862                                 struct buffer_head *bh);
2863 #define FALL_BACK_TO_NONDELALLOC 1
2864 #define CONVERT_INLINE_DATA      2
2865
2866 typedef enum {
2867         EXT4_IGET_NORMAL =      0,
2868         EXT4_IGET_SPECIAL =     0x0001, /* OK to iget a system inode */
2869         EXT4_IGET_HANDLE =      0x0002  /* Inode # is from a handle */
2870 } ext4_iget_flags;
2871
2872 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2873                                  ext4_iget_flags flags, const char *function,
2874                                  unsigned int line);
2875
2876 #define ext4_iget(sb, ino, flags) \
2877         __ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2878
2879 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2880 extern int  ext4_setattr(struct dentry *, struct iattr *);
2881 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2882 extern void ext4_evict_inode(struct inode *);
2883 extern void ext4_clear_inode(struct inode *);
2884 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2885 extern int  ext4_sync_inode(handle_t *, struct inode *);
2886 extern void ext4_dirty_inode(struct inode *, int);
2887 extern int ext4_change_inode_journal_flag(struct inode *, int);
2888 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2889 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2890                           struct ext4_iloc *iloc);
2891 extern int ext4_inode_attach_jinode(struct inode *inode);
2892 extern int ext4_can_truncate(struct inode *inode);
2893 extern int ext4_truncate(struct inode *);
2894 extern int ext4_break_layouts(struct inode *);
2895 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2896 extern void ext4_set_inode_flags(struct inode *, bool init);
2897 extern int ext4_alloc_da_blocks(struct inode *inode);
2898 extern void ext4_set_aops(struct inode *inode);
2899 extern int ext4_writepage_trans_blocks(struct inode *);
2900 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2901 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2902                              loff_t lstart, loff_t lend);
2903 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2904 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2905 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2906 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2907 extern void ext4_da_release_space(struct inode *inode, int to_free);
2908 extern void ext4_da_update_reserve_space(struct inode *inode,
2909                                         int used, int quota_claim);
2910 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2911                               ext4_fsblk_t pblk, ext4_lblk_t len);
2912
2913 /* indirect.c */
2914 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2915                                 struct ext4_map_blocks *map, int flags);
2916 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2917 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2918 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2919                                  ext4_lblk_t start, ext4_lblk_t end);
2920
2921 /* ioctl.c */
2922 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2923 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2924 extern void ext4_reset_inode_seed(struct inode *inode);
2925
2926 /* migrate.c */
2927 extern int ext4_ext_migrate(struct inode *);
2928 extern int ext4_ind_migrate(struct inode *inode);
2929
2930 /* namei.c */
2931 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2932                              struct inode *inode);
2933 extern int ext4_dirblock_csum_verify(struct inode *inode,
2934                                      struct buffer_head *bh);
2935 extern int ext4_orphan_add(handle_t *, struct inode *);
2936 extern int ext4_orphan_del(handle_t *, struct inode *);
2937 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2938                                 __u32 start_minor_hash, __u32 *next_hash);
2939 extern int ext4_search_dir(struct buffer_head *bh,
2940                            char *search_buf,
2941                            int buf_size,
2942                            struct inode *dir,
2943                            struct ext4_filename *fname,
2944                            unsigned int offset,
2945                            struct ext4_dir_entry_2 **res_dir);
2946 extern int ext4_generic_delete_entry(struct inode *dir,
2947                                      struct ext4_dir_entry_2 *de_del,
2948                                      struct buffer_head *bh,
2949                                      void *entry_buf,
2950                                      int buf_size,
2951                                      int csum_size);
2952 extern bool ext4_empty_dir(struct inode *inode);
2953
2954 /* resize.c */
2955 extern void ext4_kvfree_array_rcu(void *to_free);
2956 extern int ext4_group_add(struct super_block *sb,
2957                                 struct ext4_new_group_data *input);
2958 extern int ext4_group_extend(struct super_block *sb,
2959                                 struct ext4_super_block *es,
2960                                 ext4_fsblk_t n_blocks_count);
2961 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2962
2963 /* super.c */
2964 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2965                                          sector_t block, int op_flags);
2966 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
2967                                                    sector_t block);
2968 extern void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
2969                                 bh_end_io_t *end_io);
2970 extern int ext4_read_bh(struct buffer_head *bh, int op_flags,
2971                         bh_end_io_t *end_io);
2972 extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
2973 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
2974 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2975 extern int ext4_calculate_overhead(struct super_block *sb);
2976 extern void ext4_superblock_csum_set(struct super_block *sb);
2977 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2978                                     ext4_group_t ngroup);
2979 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2980                                      char nbuf[16]);
2981 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2982                                              ext4_group_t block_group,
2983                                              unsigned int flags);
2984
2985 extern __printf(7, 8)
2986 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
2987                   int, __u64, const char *, ...);
2988 extern __printf(6, 7)
2989 void __ext4_error_inode(struct inode *, const char *, unsigned int,
2990                         ext4_fsblk_t, int, const char *, ...);
2991 extern __printf(5, 6)
2992 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2993                      const char *, ...);
2994 extern void __ext4_std_error(struct super_block *, const char *,
2995                              unsigned int, int);
2996 extern __printf(4, 5)
2997 void __ext4_warning(struct super_block *, const char *, unsigned int,
2998                     const char *, ...);
2999 extern __printf(4, 5)
3000 void __ext4_warning_inode(const struct inode *inode, const char *function,
3001                           unsigned int line, const char *fmt, ...);
3002 extern __printf(3, 4)
3003 void __ext4_msg(struct super_block *, const char *, const char *, ...);
3004 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
3005                            const char *, unsigned int, const char *);
3006 extern __printf(7, 8)
3007 void __ext4_grp_locked_error(const char *, unsigned int,
3008                              struct super_block *, ext4_group_t,
3009                              unsigned long, ext4_fsblk_t,
3010                              const char *, ...);
3011
3012 #define EXT4_ERROR_INODE(inode, fmt, a...) \
3013         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3014
3015 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)                     \
3016         __ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3017
3018 #define ext4_error_inode_block(inode, block, err, fmt, a...)            \
3019         __ext4_error_inode((inode), __func__, __LINE__, (block), (err), \
3020                            (fmt), ## a)
3021
3022 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
3023         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3024
3025 #define ext4_abort(sb, err, fmt, a...)                                  \
3026         __ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3027
3028 #ifdef CONFIG_PRINTK
3029
3030 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
3031         __ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3032 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
3033         __ext4_error_inode((inode), (func), (line), (block),            \
3034                            (err), (fmt), ##__VA_ARGS__)
3035 #define ext4_error_file(file, func, line, block, fmt, ...)              \
3036         __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3037 #define ext4_error(sb, fmt, ...)                                        \
3038         __ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),      \
3039                 ##__VA_ARGS__)
3040 #define ext4_error_err(sb, err, fmt, ...)                               \
3041         __ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),  \
3042                 ##__VA_ARGS__)
3043 #define ext4_warning(sb, fmt, ...)                                      \
3044         __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3045 #define ext4_warning_inode(inode, fmt, ...)                             \
3046         __ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3047 #define ext4_msg(sb, level, fmt, ...)                           \
3048         __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3049 #define dump_mmp_msg(sb, mmp, msg)                                      \
3050         __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3051 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
3052         __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3053                                 fmt, ##__VA_ARGS__)
3054
3055 #else
3056
3057 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
3058 do {                                                                    \
3059         no_printk(fmt, ##__VA_ARGS__);                                  \
3060         __ext4_error_inode(inode, "", 0, block, 0, " ");                \
3061 } while (0)
3062 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
3063 do {                                                                    \
3064         no_printk(fmt, ##__VA_ARGS__);                                  \
3065         __ext4_error_inode(inode, "", 0, block, err, " ");              \
3066 } while (0)
3067 #define ext4_error_file(file, func, line, block, fmt, ...)              \
3068 do {                                                                    \
3069         no_printk(fmt, ##__VA_ARGS__);                                  \
3070         __ext4_error_file(file, "", 0, block, " ");                     \
3071 } while (0)
3072 #define ext4_error(sb, fmt, ...)                                        \
3073 do {                                                                    \
3074         no_printk(fmt, ##__VA_ARGS__);                                  \
3075         __ext4_error(sb, "", 0, false, 0, 0, " ");                      \
3076 } while (0)
3077 #define ext4_error_err(sb, err, fmt, ...)                               \
3078 do {                                                                    \
3079         no_printk(fmt, ##__VA_ARGS__);                                  \
3080         __ext4_error(sb, "", 0, false, err, 0, " ");                    \
3081 } while (0)
3082 #define ext4_warning(sb, fmt, ...)                                      \
3083 do {                                                                    \
3084         no_printk(fmt, ##__VA_ARGS__);                                  \
3085         __ext4_warning(sb, "", 0, " ");                                 \
3086 } while (0)
3087 #define ext4_warning_inode(inode, fmt, ...)                             \
3088 do {                                                                    \
3089         no_printk(fmt, ##__VA_ARGS__);                                  \
3090         __ext4_warning_inode(inode, "", 0, " ");                        \
3091 } while (0)
3092 #define ext4_msg(sb, level, fmt, ...)                                   \
3093 do {                                                                    \
3094         no_printk(fmt, ##__VA_ARGS__);                                  \
3095         __ext4_msg(sb, "", " ");                                        \
3096 } while (0)
3097 #define dump_mmp_msg(sb, mmp, msg)                                      \
3098         __dump_mmp_msg(sb, mmp, "", 0, "")
3099 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
3100 do {                                                                    \
3101         no_printk(fmt, ##__VA_ARGS__);                          \
3102         __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");       \
3103 } while (0)
3104
3105 #endif
3106
3107 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3108                                       struct ext4_group_desc *bg);
3109 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3110                                       struct ext4_group_desc *bg);
3111 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3112                                      struct ext4_group_desc *bg);
3113 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3114                                       struct ext4_group_desc *bg);
3115 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3116                                  struct ext4_group_desc *bg);
3117 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3118                                 struct ext4_group_desc *bg);
3119 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3120                                    struct ext4_group_desc *bg);
3121 extern void ext4_block_bitmap_set(struct super_block *sb,
3122                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
3123 extern void ext4_inode_bitmap_set(struct super_block *sb,
3124                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
3125 extern void ext4_inode_table_set(struct super_block *sb,
3126                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3127 extern void ext4_free_group_clusters_set(struct super_block *sb,
3128                                          struct ext4_group_desc *bg,
3129                                          __u32 count);
3130 extern void ext4_free_inodes_set(struct super_block *sb,
3131                                 struct ext4_group_desc *bg, __u32 count);
3132 extern void ext4_used_dirs_set(struct super_block *sb,
3133                                 struct ext4_group_desc *bg, __u32 count);
3134 extern void ext4_itable_unused_set(struct super_block *sb,
3135                                    struct ext4_group_desc *bg, __u32 count);
3136 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3137                                        struct ext4_group_desc *gdp);
3138 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3139                                      struct ext4_group_desc *gdp);
3140 extern int ext4_register_li_request(struct super_block *sb,
3141                                     ext4_group_t first_not_zeroed);
3142
3143 static inline int ext4_has_metadata_csum(struct super_block *sb)
3144 {
3145         WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3146                      !EXT4_SB(sb)->s_chksum_driver);
3147
3148         return ext4_has_feature_metadata_csum(sb) &&
3149                (EXT4_SB(sb)->s_chksum_driver != NULL);
3150 }
3151
3152 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3153 {
3154         return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3155 }
3156
3157 #define ext4_read_incompat_64bit_val(es, name) \
3158         (((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3159                 ? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3160                 le32_to_cpu(es->name##_lo))
3161
3162 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3163 {
3164         return ext4_read_incompat_64bit_val(es, s_blocks_count);
3165 }
3166
3167 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3168 {
3169         return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3170 }
3171
3172 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3173 {
3174         return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3175 }
3176
3177 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3178                                          ext4_fsblk_t blk)
3179 {
3180         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3181         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3182 }
3183
3184 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3185                                               ext4_fsblk_t blk)
3186 {
3187         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3188         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3189 }
3190
3191 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3192                                            ext4_fsblk_t blk)
3193 {
3194         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3195         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3196 }
3197
3198 static inline loff_t ext4_isize(struct super_block *sb,
3199                                 struct ext4_inode *raw_inode)
3200 {
3201         if (ext4_has_feature_largedir(sb) ||
3202             S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3203                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3204                         le32_to_cpu(raw_inode->i_size_lo);
3205
3206         return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3207 }
3208
3209 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3210 {
3211         raw_inode->i_size_lo = cpu_to_le32(i_size);
3212         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3213 }
3214
3215 static inline
3216 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3217                                             ext4_group_t group)
3218 {
3219          struct ext4_group_info **grp_info;
3220          long indexv, indexh;
3221          BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3222          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3223          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3224          grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3225          return grp_info[indexh];
3226 }
3227
3228 /*
3229  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3230  * the locking protocol documented in the comments of ext4_group_add()
3231  * in resize.c
3232  */
3233 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3234 {
3235         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
3236
3237         smp_rmb();
3238         return ngroups;
3239 }
3240
3241 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3242                                              ext4_group_t block_group)
3243 {
3244         return block_group >> sbi->s_log_groups_per_flex;
3245 }
3246
3247 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3248 {
3249         return 1 << sbi->s_log_groups_per_flex;
3250 }
3251
3252 #define ext4_std_error(sb, errno)                               \
3253 do {                                                            \