0b127853c5845aef5bcfeaa9ec2485f47d7939fb
[muen/linux.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/version.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42
43 #define __FS_HAS_ENCRYPTION IS_ENABLED(CONFIG_EXT4_FS_ENCRYPTION)
44 #include <linux/fscrypt.h>
45
46 /*
47  * The fourth extended filesystem constants/structures
48  */
49
50 /*
51  * with AGGRESSIVE_CHECK allocator runs consistency checks over
52  * structures. these checks slow things down a lot
53  */
54 #define AGGRESSIVE_CHECK__
55
56 /*
57  * with DOUBLE_CHECK defined mballoc creates persistent in-core
58  * bitmaps, maintains and uses them to check for double allocations
59  */
60 #define DOUBLE_CHECK__
61
62 /*
63  * Define EXT4FS_DEBUG to produce debug messages
64  */
65 #undef EXT4FS_DEBUG
66
67 /*
68  * Debug code
69  */
70 #ifdef EXT4FS_DEBUG
71 #define ext4_debug(f, a...)                                             \
72         do {                                                            \
73                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
74                         __FILE__, __LINE__, __func__);                  \
75                 printk(KERN_DEBUG f, ## a);                             \
76         } while (0)
77 #else
78 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
79 #endif
80
81 /*
82  * Turn on EXT_DEBUG to get lots of info about extents operations.
83  */
84 #define EXT_DEBUG__
85 #ifdef EXT_DEBUG
86 #define ext_debug(fmt, ...)     printk(fmt, ##__VA_ARGS__)
87 #else
88 #define ext_debug(fmt, ...)     no_printk(fmt, ##__VA_ARGS__)
89 #endif
90
91 /* data type for block offset of block group */
92 typedef int ext4_grpblk_t;
93
94 /* data type for filesystem-wide blocks number */
95 typedef unsigned long long ext4_fsblk_t;
96
97 /* data type for file logical block number */
98 typedef __u32 ext4_lblk_t;
99
100 /* data type for block group number */
101 typedef unsigned int ext4_group_t;
102
103 enum SHIFT_DIRECTION {
104         SHIFT_LEFT = 0,
105         SHIFT_RIGHT,
106 };
107
108 /*
109  * Flags used in mballoc's allocation_context flags field.
110  *
111  * Also used to show what's going on for debugging purposes when the
112  * flag field is exported via the traceport interface
113  */
114
115 /* prefer goal again. length */
116 #define EXT4_MB_HINT_MERGE              0x0001
117 /* blocks already reserved */
118 #define EXT4_MB_HINT_RESERVED           0x0002
119 /* metadata is being allocated */
120 #define EXT4_MB_HINT_METADATA           0x0004
121 /* first blocks in the file */
122 #define EXT4_MB_HINT_FIRST              0x0008
123 /* search for the best chunk */
124 #define EXT4_MB_HINT_BEST               0x0010
125 /* data is being allocated */
126 #define EXT4_MB_HINT_DATA               0x0020
127 /* don't preallocate (for tails) */
128 #define EXT4_MB_HINT_NOPREALLOC         0x0040
129 /* allocate for locality group */
130 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
131 /* allocate goal blocks or none */
132 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
133 /* goal is meaningful */
134 #define EXT4_MB_HINT_TRY_GOAL           0x0200
135 /* blocks already pre-reserved by delayed allocation */
136 #define EXT4_MB_DELALLOC_RESERVED       0x0400
137 /* We are doing stream allocation */
138 #define EXT4_MB_STREAM_ALLOC            0x0800
139 /* Use reserved root blocks if needed */
140 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
141 /* Use blocks from reserved pool */
142 #define EXT4_MB_USE_RESERVED            0x2000
143
144 struct ext4_allocation_request {
145         /* target inode for block we're allocating */
146         struct inode *inode;
147         /* how many blocks we want to allocate */
148         unsigned int len;
149         /* logical block in target inode */
150         ext4_lblk_t logical;
151         /* the closest logical allocated block to the left */
152         ext4_lblk_t lleft;
153         /* the closest logical allocated block to the right */
154         ext4_lblk_t lright;
155         /* phys. target (a hint) */
156         ext4_fsblk_t goal;
157         /* phys. block for the closest logical allocated block to the left */
158         ext4_fsblk_t pleft;
159         /* phys. block for the closest logical allocated block to the right */
160         ext4_fsblk_t pright;
161         /* flags. see above EXT4_MB_HINT_* */
162         unsigned int flags;
163 };
164
165 /*
166  * Logical to physical block mapping, used by ext4_map_blocks()
167  *
168  * This structure is used to pass requests into ext4_map_blocks() as
169  * well as to store the information returned by ext4_map_blocks().  It
170  * takes less room on the stack than a struct buffer_head.
171  */
172 #define EXT4_MAP_NEW            (1 << BH_New)
173 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
174 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
175 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
176 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
177                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
178
179 struct ext4_map_blocks {
180         ext4_fsblk_t m_pblk;
181         ext4_lblk_t m_lblk;
182         unsigned int m_len;
183         unsigned int m_flags;
184 };
185
186 /*
187  * Flags for ext4_io_end->flags
188  */
189 #define EXT4_IO_END_UNWRITTEN   0x0001
190
191 /*
192  * For converting unwritten extents on a work queue. 'handle' is used for
193  * buffered writeback.
194  */
195 typedef struct ext4_io_end {
196         struct list_head        list;           /* per-file finished IO list */
197         handle_t                *handle;        /* handle reserved for extent
198                                                  * conversion */
199         struct inode            *inode;         /* file being written to */
200         struct bio              *bio;           /* Linked list of completed
201                                                  * bios covering the extent */
202         unsigned int            flag;           /* unwritten or not */
203         atomic_t                count;          /* reference counter */
204         loff_t                  offset;         /* offset in the file */
205         ssize_t                 size;           /* size of the extent */
206 } ext4_io_end_t;
207
208 struct ext4_io_submit {
209         struct writeback_control *io_wbc;
210         struct bio              *io_bio;
211         ext4_io_end_t           *io_end;
212         sector_t                io_next_block;
213 };
214
215 /*
216  * Special inodes numbers
217  */
218 #define EXT4_BAD_INO             1      /* Bad blocks inode */
219 #define EXT4_ROOT_INO            2      /* Root inode */
220 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
221 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
222 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
223 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
224 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
225 #define EXT4_JOURNAL_INO         8      /* Journal inode */
226
227 /* First non-reserved inode for old ext4 filesystems */
228 #define EXT4_GOOD_OLD_FIRST_INO 11
229
230 /*
231  * Maximal count of links to a file
232  */
233 #define EXT4_LINK_MAX           65000
234
235 /*
236  * Macro-instructions used to manage several block sizes
237  */
238 #define EXT4_MIN_BLOCK_SIZE             1024
239 #define EXT4_MAX_BLOCK_SIZE             65536
240 #define EXT4_MIN_BLOCK_LOG_SIZE         10
241 #define EXT4_MAX_BLOCK_LOG_SIZE         16
242 #define EXT4_MAX_CLUSTER_LOG_SIZE       30
243 #ifdef __KERNEL__
244 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
245 #else
246 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
247 #endif
248 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
249 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
250                                          EXT4_SB(s)->s_cluster_bits)
251 #ifdef __KERNEL__
252 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
253 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
254 #else
255 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
256 #endif
257 #ifdef __KERNEL__
258 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
259 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
260 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
261 #else
262 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
263                                  EXT4_GOOD_OLD_INODE_SIZE : \
264                                  (s)->s_inode_size)
265 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
266                                  EXT4_GOOD_OLD_FIRST_INO : \
267                                  (s)->s_first_ino)
268 #endif
269 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
270 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
271         ((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
272                                                                   blkbits))
273
274 /* Translate a block number to a cluster number */
275 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
276 /* Translate a cluster number to a block number */
277 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
278 /* Translate # of blks to # of clusters */
279 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
280                                  (sbi)->s_cluster_bits)
281 /* Mask out the low bits to get the starting block of the cluster */
282 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &                              \
283                                   ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
284 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &                              \
285                                   ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
286 /* Get the cluster offset */
287 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &                               \
288                                  ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
289 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &                               \
290                                  ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
291
292 /*
293  * Structure of a blocks group descriptor
294  */
295 struct ext4_group_desc
296 {
297         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
298         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
299         __le32  bg_inode_table_lo;      /* Inodes table block */
300         __le16  bg_free_blocks_count_lo;/* Free blocks count */
301         __le16  bg_free_inodes_count_lo;/* Free inodes count */
302         __le16  bg_used_dirs_count_lo;  /* Directories count */
303         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
304         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
305         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
306         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
307         __le16  bg_itable_unused_lo;    /* Unused inodes count */
308         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
309         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
310         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
311         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
312         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
313         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
314         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
315         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
316         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
317         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
318         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
319         __u32   bg_reserved;
320 };
321
322 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
323         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
324          sizeof(__le16))
325 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
326         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
327          sizeof(__le16))
328
329 /*
330  * Structure of a flex block group info
331  */
332
333 struct flex_groups {
334         atomic64_t      free_clusters;
335         atomic_t        free_inodes;
336         atomic_t        used_dirs;
337 };
338
339 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
340 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
341 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
342
343 /*
344  * Macro-instructions used to manage group descriptors
345  */
346 #define EXT4_MIN_DESC_SIZE              32
347 #define EXT4_MIN_DESC_SIZE_64BIT        64
348 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
349 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
350 #ifdef __KERNEL__
351 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
352 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
353 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
354 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
355 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
356 #else
357 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
358 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
359 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
360 #endif
361
362 /*
363  * Constants relative to the data blocks
364  */
365 #define EXT4_NDIR_BLOCKS                12
366 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
367 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
368 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
369 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
370
371 /*
372  * Inode flags
373  */
374 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
375 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
376 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
377 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
378 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
379 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
380 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
381 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
382 /* Reserved for compression usage... */
383 #define EXT4_DIRTY_FL                   0x00000100
384 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
385 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
386         /* nb: was previously EXT2_ECOMPR_FL */
387 #define EXT4_ENCRYPT_FL                 0x00000800 /* encrypted file */
388 /* End compression flags --- maybe not all used */
389 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
390 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
391 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
392 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
393 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
394 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
395 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
396 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
397 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
398 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
399 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
400 #define EXT4_PROJINHERIT_FL             0x20000000 /* Create with parents projid */
401 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
402
403 #define EXT4_FL_USER_VISIBLE            0x304BDFFF /* User visible flags */
404 #define EXT4_FL_USER_MODIFIABLE         0x204BC0FF /* User modifiable flags */
405
406 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
407 #define EXT4_FL_XFLAG_VISIBLE           (EXT4_SYNC_FL | \
408                                          EXT4_IMMUTABLE_FL | \
409                                          EXT4_APPEND_FL | \
410                                          EXT4_NODUMP_FL | \
411                                          EXT4_NOATIME_FL | \
412                                          EXT4_PROJINHERIT_FL)
413
414 /* Flags that should be inherited by new inodes from their parent. */
415 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
416                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
417                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
418                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
419                            EXT4_PROJINHERIT_FL)
420
421 /* Flags that are appropriate for regular files (all but dir-specific ones). */
422 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
423
424 /* Flags that are appropriate for non-directories/regular files. */
425 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
426
427 /* Mask out flags that are inappropriate for the given type of inode. */
428 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
429 {
430         if (S_ISDIR(mode))
431                 return flags;
432         else if (S_ISREG(mode))
433                 return flags & EXT4_REG_FLMASK;
434         else
435                 return flags & EXT4_OTHER_FLMASK;
436 }
437
438 /*
439  * Inode flags used for atomic set/get
440  */
441 enum {
442         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
443         EXT4_INODE_UNRM         = 1,    /* Undelete */
444         EXT4_INODE_COMPR        = 2,    /* Compress file */
445         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
446         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
447         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
448         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
449         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
450 /* Reserved for compression usage... */
451         EXT4_INODE_DIRTY        = 8,
452         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
453         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
454         EXT4_INODE_ENCRYPT      = 11,   /* Encrypted file */
455 /* End compression flags --- maybe not all used */
456         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
457         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
458         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
459         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
460         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
461         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
462         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
463         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
464         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
465         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
466         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
467         EXT4_INODE_PROJINHERIT  = 29,   /* Create with parents projid */
468         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
469 };
470
471 /*
472  * Since it's pretty easy to mix up bit numbers and hex values, we use a
473  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
474  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
475  * any extra space in the compiled kernel image, otherwise, the build will fail.
476  * It's important that these values are the same, since we are using
477  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
478  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
479  * values found in ext2, ext3 and ext4 filesystems, and of course the values
480  * defined in e2fsprogs.
481  *
482  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
483  */
484 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
485 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
486
487 static inline void ext4_check_flag_values(void)
488 {
489         CHECK_FLAG_VALUE(SECRM);
490         CHECK_FLAG_VALUE(UNRM);
491         CHECK_FLAG_VALUE(COMPR);
492         CHECK_FLAG_VALUE(SYNC);
493         CHECK_FLAG_VALUE(IMMUTABLE);
494         CHECK_FLAG_VALUE(APPEND);
495         CHECK_FLAG_VALUE(NODUMP);
496         CHECK_FLAG_VALUE(NOATIME);
497         CHECK_FLAG_VALUE(DIRTY);
498         CHECK_FLAG_VALUE(COMPRBLK);
499         CHECK_FLAG_VALUE(NOCOMPR);
500         CHECK_FLAG_VALUE(ENCRYPT);
501         CHECK_FLAG_VALUE(INDEX);
502         CHECK_FLAG_VALUE(IMAGIC);
503         CHECK_FLAG_VALUE(JOURNAL_DATA);
504         CHECK_FLAG_VALUE(NOTAIL);
505         CHECK_FLAG_VALUE(DIRSYNC);
506         CHECK_FLAG_VALUE(TOPDIR);
507         CHECK_FLAG_VALUE(HUGE_FILE);
508         CHECK_FLAG_VALUE(EXTENTS);
509         CHECK_FLAG_VALUE(EA_INODE);
510         CHECK_FLAG_VALUE(EOFBLOCKS);
511         CHECK_FLAG_VALUE(INLINE_DATA);
512         CHECK_FLAG_VALUE(PROJINHERIT);
513         CHECK_FLAG_VALUE(RESERVED);
514 }
515
516 /* Used to pass group descriptor data when online resize is done */
517 struct ext4_new_group_input {
518         __u32 group;            /* Group number for this data */
519         __u64 block_bitmap;     /* Absolute block number of block bitmap */
520         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
521         __u64 inode_table;      /* Absolute block number of inode table start */
522         __u32 blocks_count;     /* Total number of blocks in this group */
523         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
524         __u16 unused;
525 };
526
527 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
528 struct compat_ext4_new_group_input {
529         u32 group;
530         compat_u64 block_bitmap;
531         compat_u64 inode_bitmap;
532         compat_u64 inode_table;
533         u32 blocks_count;
534         u16 reserved_blocks;
535         u16 unused;
536 };
537 #endif
538
539 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
540 struct ext4_new_group_data {
541         __u32 group;
542         __u64 block_bitmap;
543         __u64 inode_bitmap;
544         __u64 inode_table;
545         __u32 blocks_count;
546         __u16 reserved_blocks;
547         __u16 mdata_blocks;
548         __u32 free_clusters_count;
549 };
550
551 /* Indexes used to index group tables in ext4_new_group_data */
552 enum {
553         BLOCK_BITMAP = 0,       /* block bitmap */
554         INODE_BITMAP,           /* inode bitmap */
555         INODE_TABLE,            /* inode tables */
556         GROUP_TABLE_COUNT,
557 };
558
559 /*
560  * Flags used by ext4_map_blocks()
561  */
562         /* Allocate any needed blocks and/or convert an unwritten
563            extent to be an initialized ext4 */
564 #define EXT4_GET_BLOCKS_CREATE                  0x0001
565         /* Request the creation of an unwritten extent */
566 #define EXT4_GET_BLOCKS_UNWRIT_EXT              0x0002
567 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT       (EXT4_GET_BLOCKS_UNWRIT_EXT|\
568                                                  EXT4_GET_BLOCKS_CREATE)
569         /* Caller is from the delayed allocation writeout path
570          * finally doing the actual allocation of delayed blocks */
571 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
572         /* caller is from the direct IO path, request to creation of an
573         unwritten extents if not allocated, split the unwritten
574         extent if blocks has been preallocated already*/
575 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
576 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
577 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
578                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
579         /* Convert extent to initialized after IO complete */
580 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
581                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
582         /* Eventual metadata allocation (due to growing extent tree)
583          * should not fail, so try to use reserved blocks for that.*/
584 #define EXT4_GET_BLOCKS_METADATA_NOFAIL         0x0020
585         /* Don't normalize allocation size (used for fallocate) */
586 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
587         /* Request will not result in inode size update (user for fallocate) */
588 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
589         /* Convert written extents to unwritten */
590 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN       0x0100
591         /* Write zeros to newly created written extents */
592 #define EXT4_GET_BLOCKS_ZERO                    0x0200
593 #define EXT4_GET_BLOCKS_CREATE_ZERO             (EXT4_GET_BLOCKS_CREATE |\
594                                         EXT4_GET_BLOCKS_ZERO)
595         /* Caller will submit data before dropping transaction handle. This
596          * allows jbd2 to avoid submitting data before commit. */
597 #define EXT4_GET_BLOCKS_IO_SUBMIT               0x0400
598
599 /*
600  * The bit position of these flags must not overlap with any of the
601  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
602  * read_extent_tree_block(), ext4_split_extent_at(),
603  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
604  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
605  * caching the extents when reading from the extent tree while a
606  * truncate or punch hole operation is in progress.
607  */
608 #define EXT4_EX_NOCACHE                         0x40000000
609 #define EXT4_EX_FORCE_CACHE                     0x20000000
610
611 /*
612  * Flags used by ext4_free_blocks
613  */
614 #define EXT4_FREE_BLOCKS_METADATA               0x0001
615 #define EXT4_FREE_BLOCKS_FORGET                 0x0002
616 #define EXT4_FREE_BLOCKS_VALIDATED              0x0004
617 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE         0x0008
618 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
619 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
620
621 /*
622  * ioctl commands
623  */
624 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
625 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
626 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
627 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
628 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
629 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
630 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
631 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
632 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
633 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
634 #define EXT4_IOC_MIGRATE                _IO('f', 9)
635  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
636  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
637 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
638 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
639 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
640 #define EXT4_IOC_SWAP_BOOT              _IO('f', 17)
641 #define EXT4_IOC_PRECACHE_EXTENTS       _IO('f', 18)
642 #define EXT4_IOC_SET_ENCRYPTION_POLICY  FS_IOC_SET_ENCRYPTION_POLICY
643 #define EXT4_IOC_GET_ENCRYPTION_PWSALT  FS_IOC_GET_ENCRYPTION_PWSALT
644 #define EXT4_IOC_GET_ENCRYPTION_POLICY  FS_IOC_GET_ENCRYPTION_POLICY
645
646 #define EXT4_IOC_FSGETXATTR             FS_IOC_FSGETXATTR
647 #define EXT4_IOC_FSSETXATTR             FS_IOC_FSSETXATTR
648
649 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
650
651 /*
652  * Flags for going down operation
653  */
654 #define EXT4_GOING_FLAGS_DEFAULT                0x0     /* going down */
655 #define EXT4_GOING_FLAGS_LOGFLUSH               0x1     /* flush log but not data */
656 #define EXT4_GOING_FLAGS_NOLOGFLUSH             0x2     /* don't flush log nor data */
657
658
659 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
660 /*
661  * ioctl commands in 32 bit emulation
662  */
663 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
664 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
665 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
666 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
667 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
668 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
669 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
670 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
671 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
672 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
673 #endif
674
675 /* Max physical block we can address w/o extents */
676 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
677
678 /*
679  * Structure of an inode on the disk
680  */
681 struct ext4_inode {
682         __le16  i_mode;         /* File mode */
683         __le16  i_uid;          /* Low 16 bits of Owner Uid */
684         __le32  i_size_lo;      /* Size in bytes */
685         __le32  i_atime;        /* Access time */
686         __le32  i_ctime;        /* Inode Change time */
687         __le32  i_mtime;        /* Modification time */
688         __le32  i_dtime;        /* Deletion Time */
689         __le16  i_gid;          /* Low 16 bits of Group Id */
690         __le16  i_links_count;  /* Links count */
691         __le32  i_blocks_lo;    /* Blocks count */
692         __le32  i_flags;        /* File flags */
693         union {
694                 struct {
695                         __le32  l_i_version;
696                 } linux1;
697                 struct {
698                         __u32  h_i_translator;
699                 } hurd1;
700                 struct {
701                         __u32  m_i_reserved1;
702                 } masix1;
703         } osd1;                         /* OS dependent 1 */
704         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
705         __le32  i_generation;   /* File version (for NFS) */
706         __le32  i_file_acl_lo;  /* File ACL */
707         __le32  i_size_high;
708         __le32  i_obso_faddr;   /* Obsoleted fragment address */
709         union {
710                 struct {
711                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
712                         __le16  l_i_file_acl_high;
713                         __le16  l_i_uid_high;   /* these 2 fields */
714                         __le16  l_i_gid_high;   /* were reserved2[0] */
715                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
716                         __le16  l_i_reserved;
717                 } linux2;
718                 struct {
719                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
720                         __u16   h_i_mode_high;
721                         __u16   h_i_uid_high;
722                         __u16   h_i_gid_high;
723                         __u32   h_i_author;
724                 } hurd2;
725                 struct {
726                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
727                         __le16  m_i_file_acl_high;
728                         __u32   m_i_reserved2[2];
729                 } masix2;
730         } osd2;                         /* OS dependent 2 */
731         __le16  i_extra_isize;
732         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
733         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
734         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
735         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
736         __le32  i_crtime;       /* File Creation time */
737         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
738         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
739         __le32  i_projid;       /* Project ID */
740 };
741
742 struct move_extent {
743         __u32 reserved;         /* should be zero */
744         __u32 donor_fd;         /* donor file descriptor */
745         __u64 orig_start;       /* logical start offset in block for orig */
746         __u64 donor_start;      /* logical start offset in block for donor */
747         __u64 len;              /* block length to be moved */
748         __u64 moved_len;        /* moved block length */
749 };
750
751 #define EXT4_EPOCH_BITS 2
752 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
753 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
754
755 /*
756  * Extended fields will fit into an inode if the filesystem was formatted
757  * with large inodes (-I 256 or larger) and there are not currently any EAs
758  * consuming all of the available space. For new inodes we always reserve
759  * enough space for the kernel's known extended fields, but for inodes
760  * created with an old kernel this might not have been the case. None of
761  * the extended inode fields is critical for correct filesystem operation.
762  * This macro checks if a certain field fits in the inode. Note that
763  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
764  */
765 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
766         ((offsetof(typeof(*ext4_inode), field) +        \
767           sizeof((ext4_inode)->field))                  \
768         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
769             (einode)->i_extra_isize))                   \
770
771 /*
772  * We use an encoding that preserves the times for extra epoch "00":
773  *
774  * extra  msb of                         adjust for signed
775  * epoch  32-bit                         32-bit tv_sec to
776  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
777  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
778  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
779  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
780  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
781  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
782  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
783  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
784  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
785  *
786  * Note that previous versions of the kernel on 64-bit systems would
787  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
788  * 1970.  e2fsck will correct this, assuming that it is run on the
789  * affected filesystem before 2242.
790  */
791
792 static inline __le32 ext4_encode_extra_time(struct timespec *time)
793 {
794         u32 extra = sizeof(time->tv_sec) > 4 ?
795                 ((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
796         return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
797 }
798
799 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
800 {
801         if (unlikely(sizeof(time->tv_sec) > 4 &&
802                         (extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
803
804 #if 1
805                 /* Handle legacy encoding of pre-1970 dates with epoch
806                  * bits 1,1. (This backwards compatibility may be removed
807                  * at the discretion of the ext4 developers.)
808                  */
809                 u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
810                 if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
811                         extra_bits = 0;
812                 time->tv_sec += extra_bits << 32;
813 #else
814                 time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
815 #endif
816         }
817         time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
818 }
819
820 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                           \
821 do {                                                                            \
822         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);                \
823         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
824                 struct timespec ts = timespec64_to_timespec((inode)->xtime);    \
825                 (raw_inode)->xtime ## _extra =                                  \
826                                 ext4_encode_extra_time(&ts);                    \
827                 }                                                               \
828 } while (0)
829
830 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
831 do {                                                                           \
832         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
833                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
834         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
835                 (raw_inode)->xtime ## _extra =                                 \
836                                 ext4_encode_extra_time(&(einode)->xtime);      \
837 } while (0)
838
839 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                           \
840 do {                                                                            \
841         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);        \
842         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {    \
843                 struct timespec ts = timespec64_to_timespec((inode)->xtime);    \
844                 ext4_decode_extra_time(&ts,                                     \
845                                        raw_inode->xtime ## _extra);             \
846                 (inode)->xtime = timespec_to_timespec64(ts);                    \
847                 }                                                               \
848         else                                                                    \
849                 (inode)->xtime.tv_nsec = 0;                                     \
850 } while (0)
851
852
853 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
854 do {                                                                           \
855         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
856                 (einode)->xtime.tv_sec =                                       \
857                         (signed)le32_to_cpu((raw_inode)->xtime);               \
858         else                                                                   \
859                 (einode)->xtime.tv_sec = 0;                                    \
860         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
861                 ext4_decode_extra_time(&(einode)->xtime,                       \
862                                        raw_inode->xtime ## _extra);            \
863         else                                                                   \
864                 (einode)->xtime.tv_nsec = 0;                                   \
865 } while (0)
866
867 #define i_disk_version osd1.linux1.l_i_version
868
869 #if defined(__KERNEL__) || defined(__linux__)
870 #define i_reserved1     osd1.linux1.l_i_reserved1
871 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
872 #define i_blocks_high   osd2.linux2.l_i_blocks_high
873 #define i_uid_low       i_uid
874 #define i_gid_low       i_gid
875 #define i_uid_high      osd2.linux2.l_i_uid_high
876 #define i_gid_high      osd2.linux2.l_i_gid_high
877 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
878
879 #elif defined(__GNU__)
880
881 #define i_translator    osd1.hurd1.h_i_translator
882 #define i_uid_high      osd2.hurd2.h_i_uid_high
883 #define i_gid_high      osd2.hurd2.h_i_gid_high
884 #define i_author        osd2.hurd2.h_i_author
885
886 #elif defined(__masix__)
887
888 #define i_reserved1     osd1.masix1.m_i_reserved1
889 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
890 #define i_reserved2     osd2.masix2.m_i_reserved2
891
892 #endif /* defined(__KERNEL__) || defined(__linux__) */
893
894 #include "extents_status.h"
895
896 /*
897  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
898  *
899  * These are needed to avoid lockdep false positives when we need to
900  * allocate blocks to the quota inode during ext4_map_blocks(), while
901  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
902  * do quota tracking for the quota inode, this avoids deadlock (as
903  * well as infinite recursion, since it isn't turtles all the way
904  * down...)
905  *
906  *  I_DATA_SEM_NORMAL - Used for most inodes
907  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
908  *                        where the second inode has larger inode number
909  *                        than the first
910  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
911  */
912 enum {
913         I_DATA_SEM_NORMAL = 0,
914         I_DATA_SEM_OTHER,
915         I_DATA_SEM_QUOTA,
916 };
917
918
919 /*
920  * fourth extended file system inode data in memory
921  */
922 struct ext4_inode_info {
923         __le32  i_data[15];     /* unconverted */
924         __u32   i_dtime;
925         ext4_fsblk_t    i_file_acl;
926
927         /*
928          * i_block_group is the number of the block group which contains
929          * this file's inode.  Constant across the lifetime of the inode,
930          * it is used for making block allocation decisions - we try to
931          * place a file's data blocks near its inode block, and new inodes
932          * near to their parent directory's inode.
933          */
934         ext4_group_t    i_block_group;
935         ext4_lblk_t     i_dir_start_lookup;
936 #if (BITS_PER_LONG < 64)
937         unsigned long   i_state_flags;          /* Dynamic state flags */
938 #endif
939         unsigned long   i_flags;
940
941         /*
942          * Extended attributes can be read independently of the main file
943          * data. Taking i_mutex even when reading would cause contention
944          * between readers of EAs and writers of regular file data, so
945          * instead we synchronize on xattr_sem when reading or changing
946          * EAs.
947          */
948         struct rw_semaphore xattr_sem;
949
950         struct list_head i_orphan;      /* unlinked but open inodes */
951
952         /*
953          * i_disksize keeps track of what the inode size is ON DISK, not
954          * in memory.  During truncate, i_size is set to the new size by
955          * the VFS prior to calling ext4_truncate(), but the filesystem won't
956          * set i_disksize to 0 until the truncate is actually under way.
957          *
958          * The intent is that i_disksize always represents the blocks which
959          * are used by this file.  This allows recovery to restart truncate
960          * on orphans if we crash during truncate.  We actually write i_disksize
961          * into the on-disk inode when writing inodes out, instead of i_size.
962          *
963          * The only time when i_disksize and i_size may be different is when
964          * a truncate is in progress.  The only things which change i_disksize
965          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
966          */
967         loff_t  i_disksize;
968
969         /*
970          * i_data_sem is for serialising ext4_truncate() against
971          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
972          * data tree are chopped off during truncate. We can't do that in
973          * ext4 because whenever we perform intermediate commits during
974          * truncate, the inode and all the metadata blocks *must* be in a
975          * consistent state which allows truncation of the orphans to restart
976          * during recovery.  Hence we must fix the get_block-vs-truncate race
977          * by other means, so we have i_data_sem.
978          */
979         struct rw_semaphore i_data_sem;
980         /*
981          * i_mmap_sem is for serializing page faults with truncate / punch hole
982          * operations. We have to make sure that new page cannot be faulted in
983          * a section of the inode that is being punched. We cannot easily use
984          * i_data_sem for this since we need protection for the whole punch
985          * operation and i_data_sem ranks below transaction start so we have
986          * to occasionally drop it.
987          */
988         struct rw_semaphore i_mmap_sem;
989         struct inode vfs_inode;
990         struct jbd2_inode *jinode;
991
992         spinlock_t i_raw_lock;  /* protects updates to the raw inode */
993
994         /*
995          * File creation time. Its function is same as that of
996          * struct timespec i_{a,c,m}time in the generic inode.
997          */
998         struct timespec i_crtime;
999
1000         /* mballoc */
1001         struct list_head i_prealloc_list;
1002         spinlock_t i_prealloc_lock;
1003
1004         /* extents status tree */
1005         struct ext4_es_tree i_es_tree;
1006         rwlock_t i_es_lock;
1007         struct list_head i_es_list;
1008         unsigned int i_es_all_nr;       /* protected by i_es_lock */
1009         unsigned int i_es_shk_nr;       /* protected by i_es_lock */
1010         ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
1011                                            extents to shrink. Protected by
1012                                            i_es_lock  */
1013
1014         /* ialloc */
1015         ext4_group_t    i_last_alloc_group;
1016
1017         /* allocation reservation info for delalloc */
1018         /* In case of bigalloc, this refer to clusters rather than blocks */
1019         unsigned int i_reserved_data_blocks;
1020         ext4_lblk_t i_da_metadata_calc_last_lblock;
1021         int i_da_metadata_calc_len;
1022
1023         /* on-disk additional length */
1024         __u16 i_extra_isize;
1025
1026         /* Indicate the inline data space. */
1027         u16 i_inline_off;
1028         u16 i_inline_size;
1029
1030 #ifdef CONFIG_QUOTA
1031         /* quota space reservation, managed internally by quota code */
1032         qsize_t i_reserved_quota;
1033 #endif
1034
1035         /* Lock protecting lists below */
1036         spinlock_t i_completed_io_lock;
1037         /*
1038          * Completed IOs that need unwritten extents handling and have
1039          * transaction reserved
1040          */
1041         struct list_head i_rsv_conversion_list;
1042         struct work_struct i_rsv_conversion_work;
1043         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1044
1045         spinlock_t i_block_reservation_lock;
1046
1047         /*
1048          * Transactions that contain inode's metadata needed to complete
1049          * fsync and fdatasync, respectively.
1050          */
1051         tid_t i_sync_tid;
1052         tid_t i_datasync_tid;
1053
1054 #ifdef CONFIG_QUOTA
1055         struct dquot *i_dquot[MAXQUOTAS];
1056 #endif
1057
1058         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1059         __u32 i_csum_seed;
1060
1061         kprojid_t i_projid;
1062 };
1063
1064 /*
1065  * File system states
1066  */
1067 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
1068 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
1069 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
1070
1071 /*
1072  * Misc. filesystem flags
1073  */
1074 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
1075 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
1076 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
1077
1078 /*
1079  * Mount flags set via mount options or defaults
1080  */
1081 #define EXT4_MOUNT_NO_MBCACHE           0x00001 /* Do not use mbcache */
1082 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
1083 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
1084 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
1085 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
1086 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
1087 #define EXT4_MOUNT_ERRORS_MASK          0x00070
1088 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
1089 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
1090 #ifdef CONFIG_FS_DAX
1091 #define EXT4_MOUNT_DAX                  0x00200 /* Direct Access */
1092 #else
1093 #define EXT4_MOUNT_DAX                  0
1094 #endif
1095 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
1096 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
1097 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
1098 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
1099 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
1100 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
1101 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
1102 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
1103 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
1104 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
1105 #define EXT4_MOUNT_QUOTA                0x40000 /* Some quota option set */
1106 #define EXT4_MOUNT_USRQUOTA             0x80000 /* "old" user quota,
1107                                                  * enable enforcement for hidden
1108                                                  * quota files */
1109 #define EXT4_MOUNT_GRPQUOTA             0x100000 /* "old" group quota, enable
1110                                                   * enforcement for hidden quota
1111                                                   * files */
1112 #define EXT4_MOUNT_PRJQUOTA             0x200000 /* Enable project quota
1113                                                   * enforcement */
1114 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
1115 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
1116 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
1117 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
1118 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
1119 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
1120 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
1121 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
1122
1123 /*
1124  * Mount flags set either automatically (could not be set by mount option)
1125  * based on per file system feature or property or in special cases such as
1126  * distinguishing between explicit mount option definition and default.
1127  */
1128 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1129                                                       specified delalloc */
1130 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
1131                                                       size of blocksize * 8
1132                                                       blocks */
1133 #define EXT4_MOUNT2_HURD_COMPAT         0x00000004 /* Support HURD-castrated
1134                                                       file systems */
1135
1136 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM   0x00000008 /* User explicitly
1137                                                 specified journal checksum */
1138
1139 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1140                                                 ~EXT4_MOUNT_##opt
1141 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1142                                                 EXT4_MOUNT_##opt
1143 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1144                                          EXT4_MOUNT_##opt)
1145
1146 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1147                                                 ~EXT4_MOUNT2_##opt
1148 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1149                                                 EXT4_MOUNT2_##opt
1150 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1151                                          EXT4_MOUNT2_##opt)
1152
1153 #define ext4_test_and_set_bit           __test_and_set_bit_le
1154 #define ext4_set_bit                    __set_bit_le
1155 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1156 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1157 #define ext4_clear_bit                  __clear_bit_le
1158 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1159 #define ext4_test_bit                   test_bit_le
1160 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1161 #define ext4_find_next_bit              find_next_bit_le
1162
1163 extern void ext4_set_bits(void *bm, int cur, int len);
1164
1165 /*
1166  * Maximal mount counts between two filesystem checks
1167  */
1168 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1169 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1170
1171 /*
1172  * Behaviour when detecting errors
1173  */
1174 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1175 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1176 #define EXT4_ERRORS_PANIC               3       /* Panic */
1177 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1178
1179 /* Metadata checksum algorithm codes */
1180 #define EXT4_CRC32C_CHKSUM              1
1181
1182 /*
1183  * Structure of the super block
1184  */
1185 struct ext4_super_block {
1186 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1187         __le32  s_blocks_count_lo;      /* Blocks count */
1188         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1189         __le32  s_free_blocks_count_lo; /* Free blocks count */
1190 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1191         __le32  s_first_data_block;     /* First Data Block */
1192         __le32  s_log_block_size;       /* Block size */
1193         __le32  s_log_cluster_size;     /* Allocation cluster size */
1194 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1195         __le32  s_clusters_per_group;   /* # Clusters per group */
1196         __le32  s_inodes_per_group;     /* # Inodes per group */
1197         __le32  s_mtime;                /* Mount time */
1198 /*30*/  __le32  s_wtime;                /* Write time */
1199         __le16  s_mnt_count;            /* Mount count */
1200         __le16  s_max_mnt_count;        /* Maximal mount count */
1201         __le16  s_magic;                /* Magic signature */
1202         __le16  s_state;                /* File system state */
1203         __le16  s_errors;               /* Behaviour when detecting errors */
1204         __le16  s_minor_rev_level;      /* minor revision level */
1205 /*40*/  __le32  s_lastcheck;            /* time of last check */
1206         __le32  s_checkinterval;        /* max. time between checks */
1207         __le32  s_creator_os;           /* OS */
1208         __le32  s_rev_level;            /* Revision level */
1209 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1210         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1211         /*
1212          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1213          *
1214          * Note: the difference between the compatible feature set and
1215          * the incompatible feature set is that if there is a bit set
1216          * in the incompatible feature set that the kernel doesn't
1217          * know about, it should refuse to mount the filesystem.
1218          *
1219          * e2fsck's requirements are more strict; if it doesn't know
1220          * about a feature in either the compatible or incompatible
1221          * feature set, it must abort and not try to meddle with
1222          * things it doesn't understand...
1223          */
1224         __le32  s_first_ino;            /* First non-reserved inode */
1225         __le16  s_inode_size;           /* size of inode structure */
1226         __le16  s_block_group_nr;       /* block group # of this superblock */
1227         __le32  s_feature_compat;       /* compatible feature set */
1228 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1229         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1230 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1231 /*78*/  char    s_volume_name[16];      /* volume name */
1232 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1233 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1234         /*
1235          * Performance hints.  Directory preallocation should only
1236          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1237          */
1238         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1239         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1240         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1241         /*
1242          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1243          */
1244 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1245 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1246         __le32  s_journal_dev;          /* device number of journal file */
1247         __le32  s_last_orphan;          /* start of list of inodes to delete */
1248         __le32  s_hash_seed[4];         /* HTREE hash seed */
1249         __u8    s_def_hash_version;     /* Default hash version to use */
1250         __u8    s_jnl_backup_type;
1251         __le16  s_desc_size;            /* size of group descriptor */
1252 /*100*/ __le32  s_default_mount_opts;
1253         __le32  s_first_meta_bg;        /* First metablock block group */
1254         __le32  s_mkfs_time;            /* When the filesystem was created */
1255         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1256         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1257 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1258         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1259         __le32  s_free_blocks_count_hi; /* Free blocks count */
1260         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1261         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1262         __le32  s_flags;                /* Miscellaneous flags */
1263         __le16  s_raid_stride;          /* RAID stride */
1264         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1265         __le64  s_mmp_block;            /* Block for multi-mount protection */
1266         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1267         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1268         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1269         __u8    s_encryption_level;     /* versioning level for encryption */
1270         __u8    s_reserved_pad;         /* Padding to next 32bits */
1271         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1272         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1273         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1274         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1275                                               snapshot's future use */
1276         __le32  s_snapshot_list;        /* inode number of the head of the
1277                                            on-disk snapshot list */
1278 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1279         __le32  s_error_count;          /* number of fs errors */
1280         __le32  s_first_error_time;     /* first time an error happened */
1281         __le32  s_first_error_ino;      /* inode involved in first error */
1282         __le64  s_first_error_block;    /* block involved of first error */
1283         __u8    s_first_error_func[32]; /* function where the error happened */
1284         __le32  s_first_error_line;     /* line number where error happened */
1285         __le32  s_last_error_time;      /* most recent time of an error */
1286         __le32  s_last_error_ino;       /* inode involved in last error */
1287         __le32  s_last_error_line;      /* line number where error happened */
1288         __le64  s_last_error_block;     /* block involved of last error */
1289         __u8    s_last_error_func[32];  /* function where the error happened */
1290 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1291         __u8    s_mount_opts[64];
1292         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1293         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1294         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1295         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
1296         __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
1297         __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
1298         __le32  s_lpf_ino;              /* Location of the lost+found inode */
1299         __le32  s_prj_quota_inum;       /* inode for tracking project quota */
1300         __le32  s_checksum_seed;        /* crc32c(uuid) if csum_seed set */
1301         __le32  s_reserved[98];         /* Padding to the end of the block */
1302         __le32  s_checksum;             /* crc32c(superblock) */
1303 };
1304
1305 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1306
1307 #ifdef __KERNEL__
1308
1309 /*
1310  * run-time mount flags
1311  */
1312 #define EXT4_MF_MNTDIR_SAMPLED          0x0001
1313 #define EXT4_MF_FS_ABORTED              0x0002  /* Fatal error detected */
1314 #define EXT4_MF_TEST_DUMMY_ENCRYPTION   0x0004
1315
1316 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1317 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1318                                                 EXT4_MF_TEST_DUMMY_ENCRYPTION))
1319 #else
1320 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1321 #endif
1322
1323 /* Number of quota types we support */
1324 #define EXT4_MAXQUOTAS 3
1325
1326 /*
1327  * fourth extended-fs super-block data in memory
1328  */
1329 struct ext4_sb_info {
1330         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1331         unsigned long s_inodes_per_block;/* Number of inodes per block */
1332         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1333         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1334         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1335         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1336         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1337         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1338         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1339         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1340         unsigned long s_overhead;  /* # of fs overhead clusters */
1341         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1342         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1343         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1344         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1345         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1346         struct buffer_head **s_group_desc;
1347         unsigned int s_mount_opt;
1348         unsigned int s_mount_opt2;
1349         unsigned int s_mount_flags;
1350         unsigned int s_def_mount_opt;
1351         ext4_fsblk_t s_sb_block;
1352         atomic64_t s_resv_clusters;
1353         kuid_t s_resuid;
1354         kgid_t s_resgid;
1355         unsigned short s_mount_state;
1356         unsigned short s_pad;
1357         int s_addr_per_block_bits;
1358         int s_desc_per_block_bits;
1359         int s_inode_size;
1360         int s_first_ino;
1361         unsigned int s_inode_readahead_blks;
1362         unsigned int s_inode_goal;
1363         u32 s_hash_seed[4];
1364         int s_def_hash_version;
1365         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1366         struct percpu_counter s_freeclusters_counter;
1367         struct percpu_counter s_freeinodes_counter;
1368         struct percpu_counter s_dirs_counter;
1369         struct percpu_counter s_dirtyclusters_counter;
1370         struct blockgroup_lock *s_blockgroup_lock;
1371         struct proc_dir_entry *s_proc;
1372         struct kobject s_kobj;
1373         struct completion s_kobj_unregister;
1374         struct super_block *s_sb;
1375
1376         /* Journaling */
1377         struct journal_s *s_journal;
1378         struct list_head s_orphan;
1379         struct mutex s_orphan_lock;
1380         unsigned long s_ext4_flags;             /* Ext4 superblock flags */
1381         unsigned long s_commit_interval;
1382         u32 s_max_batch_time;
1383         u32 s_min_batch_time;
1384         struct block_device *journal_bdev;
1385 #ifdef CONFIG_QUOTA
1386         char *s_qf_names[EXT4_MAXQUOTAS];       /* Names of quota files with journalled quota */
1387         int s_jquota_fmt;                       /* Format of quota to use */
1388 #endif
1389         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1390         struct rb_root system_blks;
1391
1392 #ifdef EXTENTS_STATS
1393         /* ext4 extents stats */
1394         unsigned long s_ext_min;
1395         unsigned long s_ext_max;
1396         unsigned long s_depth_max;
1397         spinlock_t s_ext_stats_lock;
1398         unsigned long s_ext_blocks;
1399         unsigned long s_ext_extents;
1400 #endif
1401
1402         /* for buddy allocator */
1403         struct ext4_group_info ***s_group_info;
1404         struct inode *s_buddy_cache;
1405         spinlock_t s_md_lock;
1406         unsigned short *s_mb_offsets;
1407         unsigned int *s_mb_maxs;
1408         unsigned int s_group_info_size;
1409         unsigned int s_mb_free_pending;
1410         struct list_head s_freed_data_list;     /* List of blocks to be freed
1411                                                    after commit completed */
1412
1413         /* tunables */
1414         unsigned long s_stripe;
1415         unsigned int s_mb_stream_request;
1416         unsigned int s_mb_max_to_scan;
1417         unsigned int s_mb_min_to_scan;
1418         unsigned int s_mb_stats;
1419         unsigned int s_mb_order2_reqs;
1420         unsigned int s_mb_group_prealloc;
1421         unsigned int s_max_dir_size_kb;
1422         /* where last allocation was done - for stream allocation */
1423         unsigned long s_mb_last_group;
1424         unsigned long s_mb_last_start;
1425
1426         /* stats for buddy allocator */
1427         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1428         atomic_t s_bal_success; /* we found long enough chunks */
1429         atomic_t s_bal_allocated;       /* in blocks */
1430         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1431         atomic_t s_bal_goals;   /* goal hits */
1432         atomic_t s_bal_breaks;  /* too long searches */
1433         atomic_t s_bal_2orders; /* 2^order hits */
1434         spinlock_t s_bal_lock;
1435         unsigned long s_mb_buddies_generated;
1436         unsigned long long s_mb_generation_time;
1437         atomic_t s_mb_lost_chunks;
1438         atomic_t s_mb_preallocated;
1439         atomic_t s_mb_discarded;
1440         atomic_t s_lock_busy;
1441
1442         /* locality groups */
1443         struct ext4_locality_group __percpu *s_locality_groups;
1444
1445         /* for write statistics */
1446         unsigned long s_sectors_written_start;
1447         u64 s_kbytes_written;
1448
1449         /* the size of zero-out chunk */
1450         unsigned int s_extent_max_zeroout_kb;
1451
1452         unsigned int s_log_groups_per_flex;
1453         struct flex_groups *s_flex_groups;
1454         ext4_group_t s_flex_groups_allocated;
1455
1456         /* workqueue for reserved extent conversions (buffered io) */
1457         struct workqueue_struct *rsv_conversion_wq;
1458
1459         /* timer for periodic error stats printing */
1460         struct timer_list s_err_report;
1461
1462         /* Lazy inode table initialization info */
1463         struct ext4_li_request *s_li_request;
1464         /* Wait multiplier for lazy initialization thread */
1465         unsigned int s_li_wait_mult;
1466
1467         /* Kernel thread for multiple mount protection */
1468         struct task_struct *s_mmp_tsk;
1469
1470         /* record the last minlen when FITRIM is called. */
1471         atomic_t s_last_trim_minblks;
1472
1473         /* Reference to checksum algorithm driver via cryptoapi */
1474         struct crypto_shash *s_chksum_driver;
1475
1476         /* Precomputed FS UUID checksum for seeding other checksums */
1477         __u32 s_csum_seed;
1478
1479         /* Reclaim extents from extent status tree */
1480         struct shrinker s_es_shrinker;
1481         struct list_head s_es_list;     /* List of inodes with reclaimable extents */
1482         long s_es_nr_inode;
1483         struct ext4_es_stats s_es_stats;
1484         struct mb_cache *s_ea_block_cache;
1485         struct mb_cache *s_ea_inode_cache;
1486         spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1487
1488         /* Ratelimit ext4 messages. */
1489         struct ratelimit_state s_err_ratelimit_state;
1490         struct ratelimit_state s_warning_ratelimit_state;
1491         struct ratelimit_state s_msg_ratelimit_state;
1492
1493         /* Barrier between changing inodes' journal flags and writepages ops. */
1494         struct percpu_rw_semaphore s_journal_flag_rwsem;
1495         struct dax_device *s_daxdev;
1496 };
1497
1498 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1499 {
1500         return sb->s_fs_info;
1501 }
1502 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1503 {
1504         return container_of(inode, struct ext4_inode_info, vfs_inode);
1505 }
1506
1507 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1508 {
1509         return ino == EXT4_ROOT_INO ||
1510                 ino == EXT4_USR_QUOTA_INO ||
1511                 ino == EXT4_GRP_QUOTA_INO ||
1512                 ino == EXT4_BOOT_LOADER_INO ||
1513                 ino == EXT4_JOURNAL_INO ||
1514                 ino == EXT4_RESIZE_INO ||
1515                 (ino >= EXT4_FIRST_INO(sb) &&
1516                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1517 }
1518
1519 /*
1520  * Inode dynamic state flags
1521  */
1522 enum {
1523         EXT4_STATE_JDATA,               /* journaled data exists */
1524         EXT4_STATE_NEW,                 /* inode is newly created */
1525         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1526         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1527         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1528         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1529         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1530         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1531         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1532         EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
1533         EXT4_STATE_LUSTRE_EA_INODE,     /* Lustre-style ea_inode */
1534 };
1535
1536 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1537 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1538 {                                                                       \
1539         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1540 }                                                                       \
1541 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1542 {                                                                       \
1543         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1544 }                                                                       \
1545 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1546 {                                                                       \
1547         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1548 }
1549
1550 /* Add these declarations here only so that these functions can be
1551  * found by name.  Otherwise, they are very hard to locate. */
1552 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1553 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1554 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1555 EXT4_INODE_BIT_FNS(flag, flags, 0)
1556
1557 /* Add these declarations here only so that these functions can be
1558  * found by name.  Otherwise, they are very hard to locate. */
1559 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1560 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1561 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1562 #if (BITS_PER_LONG < 64)
1563 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1564
1565 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1566 {
1567         (ei)->i_state_flags = 0;
1568 }
1569 #else
1570 EXT4_INODE_BIT_FNS(state, flags, 32)
1571
1572 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1573 {
1574         /* We depend on the fact that callers will set i_flags */
1575 }
1576 #endif
1577 #else
1578 /* Assume that user mode programs are passing in an ext4fs superblock, not
1579  * a kernel struct super_block.  This will allow us to call the feature-test
1580  * macros from user land. */
1581 #define EXT4_SB(sb)     (sb)
1582 #endif
1583
1584 /*
1585  * Returns true if the inode is inode is encrypted
1586  */
1587 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1588
1589 /*
1590  * Codes for operating systems
1591  */
1592 #define EXT4_OS_LINUX           0
1593 #define EXT4_OS_HURD            1
1594 #define EXT4_OS_MASIX           2
1595 #define EXT4_OS_FREEBSD         3
1596 #define EXT4_OS_LITES           4
1597
1598 /*
1599  * Revision levels
1600  */
1601 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1602 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1603
1604 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1605 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1606
1607 #define EXT4_GOOD_OLD_INODE_SIZE 128
1608
1609 /*
1610  * Feature set definitions
1611  */
1612
1613 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1614 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1615 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1616 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1617 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1618 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1619 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2       0x0200
1620
1621 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1622 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1623 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1624 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1625 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1626 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1627 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1628 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1629 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1630 /*
1631  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1632  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1633  * all other data structures' checksums.  However, the METADATA_CSUM and
1634  * GDT_CSUM bits are mutually exclusive.
1635  */
1636 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1637 #define EXT4_FEATURE_RO_COMPAT_READONLY         0x1000
1638 #define EXT4_FEATURE_RO_COMPAT_PROJECT          0x2000
1639
1640 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1641 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1642 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1643 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1644 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1645 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1646 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1647 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1648 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1649 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1650 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1651 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED         0x2000
1652 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1653 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1654 #define EXT4_FEATURE_INCOMPAT_ENCRYPT           0x10000
1655
1656 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1657 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1658 { \
1659         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1660                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1661 } \
1662 static inline void ext4_set_feature_##name(struct super_block *sb) \
1663 { \
1664         EXT4_SB(sb)->s_es->s_feature_compat |= \
1665                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1666 } \
1667 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1668 { \
1669         EXT4_SB(sb)->s_es->s_feature_compat &= \
1670                 ~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1671 }
1672
1673 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1674 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1675 { \
1676         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1677                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1678 } \
1679 static inline void ext4_set_feature_##name(struct super_block *sb) \
1680 { \
1681         EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1682                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1683 } \
1684 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1685 { \
1686         EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1687                 ~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1688 }
1689
1690 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1691 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1692 { \
1693         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1694                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1695 } \
1696 static inline void ext4_set_feature_##name(struct super_block *sb) \
1697 { \
1698         EXT4_SB(sb)->s_es->s_feature_incompat |= \
1699                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1700 } \
1701 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1702 { \
1703         EXT4_SB(sb)->s_es->s_feature_incompat &= \
1704                 ~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1705 }
1706
1707 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,         DIR_PREALLOC)
1708 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,        IMAGIC_INODES)
1709 EXT4_FEATURE_COMPAT_FUNCS(journal,              HAS_JOURNAL)
1710 EXT4_FEATURE_COMPAT_FUNCS(xattr,                EXT_ATTR)
1711 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,         RESIZE_INODE)
1712 EXT4_FEATURE_COMPAT_FUNCS(dir_index,            DIR_INDEX)
1713 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,        SPARSE_SUPER2)
1714
1715 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,      SPARSE_SUPER)
1716 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,        LARGE_FILE)
1717 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,         BTREE_DIR)
1718 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,         HUGE_FILE)
1719 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,          GDT_CSUM)
1720 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,         DIR_NLINK)
1721 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,       EXTRA_ISIZE)
1722 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,             QUOTA)
1723 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,          BIGALLOC)
1724 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,     METADATA_CSUM)
1725 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,          READONLY)
1726 EXT4_FEATURE_RO_COMPAT_FUNCS(project,           PROJECT)
1727
1728 EXT4_FEATURE_INCOMPAT_FUNCS(compression,        COMPRESSION)
1729 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,           FILETYPE)
1730 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,     RECOVER)
1731 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,        JOURNAL_DEV)
1732 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,            META_BG)
1733 EXT4_FEATURE_INCOMPAT_FUNCS(extents,            EXTENTS)
1734 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,              64BIT)
1735 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,                MMP)
1736 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,            FLEX_BG)
1737 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,           EA_INODE)
1738 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,            DIRDATA)
1739 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,          CSUM_SEED)
1740 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,           LARGEDIR)
1741 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,        INLINE_DATA)
1742 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,            ENCRYPT)
1743
1744 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1745 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1746                                          EXT4_FEATURE_INCOMPAT_META_BG)
1747 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1748                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1749                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1750
1751 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1752 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1753                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1754                                          EXT4_FEATURE_INCOMPAT_META_BG)
1755 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1756                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1757                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1758
1759 #define EXT4_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1760 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1761                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1762                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1763                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1764                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1765                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1766                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
1767                                          EXT4_FEATURE_INCOMPAT_MMP | \
1768                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1769                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1770                                          EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1771                                          EXT4_FEATURE_INCOMPAT_LARGEDIR)
1772 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1773                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1774                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1775                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1776                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1777                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1778                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1779                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1780                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1781                                          EXT4_FEATURE_RO_COMPAT_QUOTA |\
1782                                          EXT4_FEATURE_RO_COMPAT_PROJECT)
1783
1784 #define EXTN_FEATURE_FUNCS(ver) \
1785 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1786 { \
1787         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1788                 cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1789 } \
1790 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1791 { \
1792         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1793                 cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1794 } \
1795 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1796 { \
1797         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1798                 cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1799 }
1800
1801 EXTN_FEATURE_FUNCS(2)
1802 EXTN_FEATURE_FUNCS(3)
1803 EXTN_FEATURE_FUNCS(4)
1804
1805 static inline bool ext4_has_compat_features(struct super_block *sb)
1806 {
1807         return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1808 }
1809 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1810 {
1811         return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1812 }
1813 static inline bool ext4_has_incompat_features(struct super_block *sb)
1814 {
1815         return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1816 }
1817
1818 /*
1819  * Superblock flags
1820  */
1821 #define EXT4_FLAGS_RESIZING     0
1822 #define EXT4_FLAGS_SHUTDOWN     1
1823
1824 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1825 {
1826         return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1827 }
1828
1829
1830 /*
1831  * Default values for user and/or group using reserved blocks
1832  */
1833 #define EXT4_DEF_RESUID         0
1834 #define EXT4_DEF_RESGID         0
1835
1836 /*
1837  * Default project ID
1838  */
1839 #define EXT4_DEF_PROJID         0
1840
1841 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1842
1843 /*
1844  * Default mount options
1845  */
1846 #define EXT4_DEFM_DEBUG         0x0001
1847 #define EXT4_DEFM_BSDGROUPS     0x0002
1848 #define EXT4_DEFM_XATTR_USER    0x0004
1849 #define EXT4_DEFM_ACL           0x0008
1850 #define EXT4_DEFM_UID16         0x0010
1851 #define EXT4_DEFM_JMODE         0x0060
1852 #define EXT4_DEFM_JMODE_DATA    0x0020
1853 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1854 #define EXT4_DEFM_JMODE_WBACK   0x0060
1855 #define EXT4_DEFM_NOBARRIER     0x0100
1856 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1857 #define EXT4_DEFM_DISCARD       0x0400
1858 #define EXT4_DEFM_NODELALLOC    0x0800
1859
1860 /*
1861  * Default journal batch times
1862  */
1863 #define EXT4_DEF_MIN_BATCH_TIME 0
1864 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1865
1866 /*
1867  * Minimum number of groups in a flexgroup before we separate out
1868  * directories into the first block group of a flexgroup
1869  */
1870 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1871
1872 /*
1873  * Structure of a directory entry
1874  */
1875 #define EXT4_NAME_LEN 255
1876
1877 struct ext4_dir_entry {
1878         __le32  inode;                  /* Inode number */
1879         __le16  rec_len;                /* Directory entry length */
1880         __le16  name_len;               /* Name length */
1881         char    name[EXT4_NAME_LEN];    /* File name */
1882 };
1883
1884 /*
1885  * The new version of the directory entry.  Since EXT4 structures are
1886  * stored in intel byte order, and the name_len field could never be
1887  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1888  * file_type field.
1889  */
1890 struct ext4_dir_entry_2 {
1891         __le32  inode;                  /* Inode number */
1892         __le16  rec_len;                /* Directory entry length */
1893         __u8    name_len;               /* Name length */
1894         __u8    file_type;
1895         char    name[EXT4_NAME_LEN];    /* File name */
1896 };
1897
1898 /*
1899  * This is a bogus directory entry at the end of each leaf block that
1900  * records checksums.
1901  */
1902 struct ext4_dir_entry_tail {
1903         __le32  det_reserved_zero1;     /* Pretend to be unused */
1904         __le16  det_rec_len;            /* 12 */
1905         __u8    det_reserved_zero2;     /* Zero name length */
1906         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1907         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1908 };
1909
1910 #define EXT4_DIRENT_TAIL(block, blocksize) \
1911         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1912                                         ((blocksize) - \
1913                                          sizeof(struct ext4_dir_entry_tail))))
1914
1915 /*
1916  * Ext4 directory file types.  Only the low 3 bits are used.  The
1917  * other bits are reserved for now.
1918  */
1919 #define EXT4_FT_UNKNOWN         0
1920 #define EXT4_FT_REG_FILE        1
1921 #define EXT4_FT_DIR             2
1922 #define EXT4_FT_CHRDEV          3
1923 #define EXT4_FT_BLKDEV          4
1924 #define EXT4_FT_FIFO            5
1925 #define EXT4_FT_SOCK            6
1926 #define EXT4_FT_SYMLINK         7
1927
1928 #define EXT4_FT_MAX             8
1929
1930 #define EXT4_FT_DIR_CSUM        0xDE
1931
1932 /*
1933  * EXT4_DIR_PAD defines the directory entries boundaries
1934  *
1935  * NOTE: It must be a multiple of 4
1936  */
1937 #define EXT4_DIR_PAD                    4
1938 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1939 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1940                                          ~EXT4_DIR_ROUND)
1941 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1942
1943 /*
1944  * If we ever get support for fs block sizes > page_size, we'll need
1945  * to remove the #if statements in the next two functions...
1946  */
1947 static inline unsigned int
1948 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1949 {
1950         unsigned len = le16_to_cpu(dlen);
1951
1952 #if (PAGE_SIZE >= 65536)
1953         if (len == EXT4_MAX_REC_LEN || len == 0)
1954                 return blocksize;
1955         return (len & 65532) | ((len & 3) << 16);
1956 #else
1957         return len;
1958 #endif
1959 }
1960
1961 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1962 {
1963         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1964                 BUG();
1965 #if (PAGE_SIZE >= 65536)
1966         if (len < 65536)
1967                 return cpu_to_le16(len);
1968         if (len == blocksize) {
1969                 if (blocksize == 65536)
1970                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1971                 else
1972                         return cpu_to_le16(0);
1973         }
1974         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1975 #else
1976         return cpu_to_le16(len);
1977 #endif
1978 }
1979
1980 /*
1981  * Hash Tree Directory indexing
1982  * (c) Daniel Phillips, 2001
1983  */
1984
1985 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
1986                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1987 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
1988                     !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
1989 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1990
1991 /* Legal values for the dx_root hash_version field: */
1992
1993 #define DX_HASH_LEGACY                  0
1994 #define DX_HASH_HALF_MD4                1
1995 #define DX_HASH_TEA                     2
1996 #define DX_HASH_LEGACY_UNSIGNED         3
1997 #define DX_HASH_HALF_MD4_UNSIGNED       4
1998 #define DX_HASH_TEA_UNSIGNED            5
1999
2000 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2001                               const void *address, unsigned int length)
2002 {
2003         struct {
2004                 struct shash_desc shash;
2005                 char ctx[4];
2006         } desc;
2007
2008         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2009
2010         desc.shash.tfm = sbi->s_chksum_driver;
2011         desc.shash.flags = 0;
2012         *(u32 *)desc.ctx = crc;
2013
2014         BUG_ON(crypto_shash_update(&desc.shash, address, length));
2015
2016         return *(u32 *)desc.ctx;
2017 }
2018
2019 #ifdef __KERNEL__
2020
2021 /* hash info structure used by the directory hash */
2022 struct dx_hash_info
2023 {
2024         u32             hash;
2025         u32             minor_hash;
2026         int             hash_version;
2027         u32             *seed;
2028 };
2029
2030
2031 /* 32 and 64 bit signed EOF for dx directories */
2032 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2033 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2034
2035
2036 /*
2037  * Control parameters used by ext4_htree_next_block
2038  */
2039 #define HASH_NB_ALWAYS          1
2040
2041 struct ext4_filename {
2042         const struct qstr *usr_fname;
2043         struct fscrypt_str disk_name;
2044         struct dx_hash_info hinfo;
2045 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2046         struct fscrypt_str crypto_buf;
2047 #endif
2048 };
2049
2050 #define fname_name(p) ((p)->disk_name.name)
2051 #define fname_len(p)  ((p)->disk_name.len)
2052
2053 /*
2054  * Describe an inode's exact location on disk and in memory
2055  */
2056 struct ext4_iloc
2057 {
2058         struct buffer_head *bh;
2059         unsigned long offset;
2060         ext4_group_t block_group;
2061 };
2062
2063 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2064 {
2065         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2066 }
2067
2068 static inline bool ext4_is_quota_file(struct inode *inode)
2069 {
2070         return IS_NOQUOTA(inode) &&
2071                !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2072 }
2073
2074 /*
2075  * This structure is stuffed into the struct file's private_data field
2076  * for directories.  It is where we put information so that we can do
2077  * readdir operations in hash tree order.
2078  */
2079 struct dir_private_info {
2080         struct rb_root  root;
2081         struct rb_node  *curr_node;
2082         struct fname    *extra_fname;
2083         loff_t          last_pos;
2084         __u32           curr_hash;
2085         __u32           curr_minor_hash;
2086         __u32           next_hash;
2087 };
2088
2089 /* calculate the first block number of the group */
2090 static inline ext4_fsblk_t
2091 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2092 {
2093         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2094                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2095 }
2096
2097 /*
2098  * Special error return code only used by dx_probe() and its callers.
2099  */
2100 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
2101
2102 /* htree levels for ext4 */
2103 #define EXT4_HTREE_LEVEL_COMPAT 2
2104 #define EXT4_HTREE_LEVEL        3
2105
2106 static inline int ext4_dir_htree_level(struct super_block *sb)
2107 {
2108         return ext4_has_feature_largedir(sb) ?
2109                 EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2110 }
2111
2112 /*
2113  * Timeout and state flag for lazy initialization inode thread.
2114  */
2115 #define EXT4_DEF_LI_WAIT_MULT                   10
2116 #define EXT4_DEF_LI_MAX_START_DELAY             5
2117 #define EXT4_LAZYINIT_QUIT                      0x0001
2118 #define EXT4_LAZYINIT_RUNNING                   0x0002
2119
2120 /*
2121  * Lazy inode table initialization info
2122  */
2123 struct ext4_lazy_init {
2124         unsigned long           li_state;
2125         struct list_head        li_request_list;
2126         struct mutex            li_list_mtx;
2127 };
2128
2129 struct ext4_li_request {
2130         struct super_block      *lr_super;
2131         struct ext4_sb_info     *lr_sbi;
2132         ext4_group_t            lr_next_group;
2133         struct list_head        lr_request;
2134         unsigned long           lr_next_sched;
2135         unsigned long           lr_timeout;
2136 };
2137
2138 struct ext4_features {
2139         struct kobject f_kobj;
2140         struct completion f_kobj_unregister;
2141 };
2142
2143 /*
2144  * This structure will be used for multiple mount protection. It will be
2145  * written into the block number saved in the s_mmp_block field in the
2146  * superblock. Programs that check MMP should assume that if
2147  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2148  * to use the filesystem, regardless of how old the timestamp is.
2149  */
2150 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2151 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2152 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2153 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2154
2155 struct mmp_struct {
2156         __le32  mmp_magic;              /* Magic number for MMP */
2157         __le32  mmp_seq;                /* Sequence no. updated periodically */
2158
2159         /*
2160          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2161          * purposes and do not affect the correctness of the algorithm
2162          */
2163         __le64  mmp_time;               /* Time last updated */
2164         char    mmp_nodename[64];       /* Node which last updated MMP block */
2165         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
2166
2167         /*
2168          * mmp_check_interval is used to verify if the MMP block has been
2169          * updated on the block device. The value is updated based on the
2170          * maximum time to write the MMP block during an update cycle.
2171          */
2172         __le16  mmp_check_interval;
2173
2174         __le16  mmp_pad1;
2175         __le32  mmp_pad2[226];
2176         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
2177 };
2178
2179 /* arguments passed to the mmp thread */
2180 struct mmpd_data {
2181         struct buffer_head *bh; /* bh from initial read_mmp_block() */
2182         struct super_block *sb;  /* super block of the fs */
2183 };
2184
2185 /*
2186  * Check interval multiplier
2187  * The MMP block is written every update interval and initially checked every
2188  * update interval x the multiplier (the value is then adapted based on the
2189  * write latency). The reason is that writes can be delayed under load and we
2190  * don't want readers to incorrectly assume that the filesystem is no longer
2191  * in use.
2192  */
2193 #define EXT4_MMP_CHECK_MULT             2UL
2194
2195 /*
2196  * Minimum interval for MMP checking in seconds.
2197  */
2198 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
2199
2200 /*
2201  * Maximum interval for MMP checking in seconds.
2202  */
2203 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
2204
2205 /*
2206  * Function prototypes
2207  */
2208
2209 /*
2210  * Ok, these declarations are also in <linux/kernel.h> but none of the
2211  * ext4 source programs needs to include it so they are duplicated here.
2212  */
2213 # define NORET_TYPE     /**/
2214 # define ATTRIB_NORET   __attribute__((noreturn))
2215 # define NORET_AND      noreturn,
2216
2217 /* bitmap.c */
2218 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2219 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2220                                 struct ext4_group_desc *gdp,
2221                                 struct buffer_head *bh, int sz);
2222 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2223                                   struct ext4_group_desc *gdp,
2224                                   struct buffer_head *bh, int sz);
2225 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2226                                 struct ext4_group_desc *gdp,
2227                                 struct buffer_head *bh);
2228 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2229                                   struct ext4_group_desc *gdp,
2230                                   struct buffer_head *bh);
2231
2232 /* balloc.c */
2233 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2234                                          ext4_fsblk_t blocknr,
2235                                          ext4_group_t *blockgrpp,
2236                                          ext4_grpblk_t *offsetp);
2237 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2238                                           ext4_fsblk_t block);
2239
2240 extern unsigned int ext4_block_group(struct super_block *sb,
2241                         ext4_fsblk_t blocknr);
2242 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2243                         ext4_fsblk_t blocknr);
2244 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2245 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2246                         ext4_group_t group);
2247 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2248                                          ext4_fsblk_t goal,
2249                                          unsigned int flags,
2250                                          unsigned long *count,
2251                                          int *errp);
2252 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2253                                     s64 nclusters, unsigned int flags);
2254 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2255 extern void ext4_check_blocks_bitmap(struct super_block *);
2256 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2257                                                     ext4_group_t block_group,
2258                                                     struct buffer_head ** bh);
2259 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2260
2261 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2262                                                 ext4_group_t block_group);
2263 extern int ext4_wait_block_bitmap(struct super_block *sb,
2264                                   ext4_group_t block_group,
2265                                   struct buffer_head *bh);
2266 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2267                                                   ext4_group_t block_group);
2268 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2269                                               ext4_group_t block_group,
2270                                               struct ext4_group_desc *gdp);
2271 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2272
2273 static inline bool ext4_encrypted_inode(struct inode *inode)
2274 {
2275         return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2276 }
2277
2278 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2279 static inline int ext4_fname_setup_filename(struct inode *dir,
2280                         const struct qstr *iname,
2281                         int lookup, struct ext4_filename *fname)
2282 {
2283         struct fscrypt_name name;
2284         int err;
2285
2286         memset(fname, 0, sizeof(struct ext4_filename));
2287
2288         err = fscrypt_setup_filename(dir, iname, lookup, &name);
2289
2290         fname->usr_fname = name.usr_fname;
2291         fname->disk_name = name.disk_name;
2292         fname->hinfo.hash = name.hash;
2293         fname->hinfo.minor_hash = name.minor_hash;
2294         fname->crypto_buf = name.crypto_buf;
2295         return err;
2296 }
2297
2298 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2299 {
2300         struct fscrypt_name name;
2301
2302         name.crypto_buf = fname->crypto_buf;
2303         fscrypt_free_filename(&name);
2304
2305         fname->crypto_buf.name = NULL;
2306         fname->usr_fname = NULL;
2307         fname->disk_name.name = NULL;
2308 }
2309 #else
2310 static inline int ext4_fname_setup_filename(struct inode *dir,
2311                 const struct qstr *iname,
2312                 int lookup, struct ext4_filename *fname)
2313 {
2314         fname->usr_fname = iname;
2315         fname->disk_name.name = (unsigned char *) iname->name;
2316         fname->disk_name.len = iname->len;
2317         return 0;
2318 }
2319 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2320
2321 #endif
2322
2323 /* dir.c */
2324 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2325                                   struct file *,
2326                                   struct ext4_dir_entry_2 *,
2327                                   struct buffer_head *, char *, int,
2328                                   unsigned int);
2329 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)      \
2330         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2331                                         (de), (bh), (buf), (size), (offset)))
2332 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2333                                 __u32 minor_hash,
2334                                 struct ext4_dir_entry_2 *dirent,
2335                                 struct fscrypt_str *ent_name);
2336 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2337 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2338                              struct buffer_head *bh,
2339                              void *buf, int buf_size,
2340                              struct ext4_filename *fname,
2341                              struct ext4_dir_entry_2 **dest_de);
2342 void ext4_insert_dentry(struct inode *inode,
2343                         struct ext4_dir_entry_2 *de,
2344                         int buf_size,
2345                         struct ext4_filename *fname);
2346 static inline void ext4_update_dx_flag(struct inode *inode)
2347 {
2348         if (!ext4_has_feature_dir_index(inode->i_sb))
2349                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2350 }
2351 static const unsigned char ext4_filetype_table[] = {
2352         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2353 };
2354
2355 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2356 {
2357         if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2358                 return DT_UNKNOWN;
2359
2360         return ext4_filetype_table[filetype];
2361 }
2362 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2363                              void *buf, int buf_size);
2364
2365 /* fsync.c */
2366 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2367
2368 /* hash.c */
2369 extern int ext4fs_dirhash(const char *name, int len, struct
2370                           dx_hash_info *hinfo);
2371
2372 /* ialloc.c */
2373 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2374                                       const struct qstr *qstr, __u32 goal,
2375                                       uid_t *owner, __u32 i_flags,
2376                                       int handle_type, unsigned int line_no,
2377                                       int nblocks);
2378
2379 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2380         __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2381                          i_flags, 0, 0, 0)
2382 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2383                                     type, nblocks)                  \
2384         __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2385                          0, (type), __LINE__, (nblocks))
2386
2387
2388 extern void ext4_free_inode(handle_t *, struct inode *);
2389 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2390 extern unsigned long ext4_count_free_inodes(struct super_block *);
2391 extern unsigned long ext4_count_dirs(struct super_block *);
2392 extern void ext4_check_inodes_bitmap(struct super_block *);
2393 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2394 extern int ext4_init_inode_table(struct super_block *sb,
2395                                  ext4_group_t group, int barrier);
2396 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2397
2398 /* mballoc.c */
2399 extern const struct seq_operations ext4_mb_seq_groups_ops;
2400 extern long ext4_mb_stats;
2401 extern long ext4_mb_max_to_scan;
2402 extern int ext4_mb_init(struct super_block *);
2403 extern int ext4_mb_release(struct super_block *);
2404 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2405                                 struct ext4_allocation_request *, int *);
2406 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2407 extern void ext4_discard_preallocations(struct inode *);
2408 extern int __init ext4_init_mballoc(void);
2409 extern void ext4_exit_mballoc(void);
2410 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2411                              struct buffer_head *bh, ext4_fsblk_t block,
2412                              unsigned long count, int flags);
2413 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2414                                    ext4_group_t ngroups);
2415 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2416                 ext4_group_t i, struct ext4_group_desc *desc);
2417 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2418                                 ext4_fsblk_t block, unsigned long count);
2419 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2420 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2421
2422 /* inode.c */
2423 int ext4_inode_is_fast_symlink(struct inode *inode);
2424 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2425 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2426 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2427                      bool wait, struct buffer_head **bhs);
2428 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2429                              struct buffer_head *bh_result, int create);
2430 int ext4_get_block(struct inode *inode, sector_t iblock,
2431                    struct buffer_head *bh_result, int create);
2432 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2433                        struct buffer_head *bh_result, int create);
2434 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2435                            struct buffer_head *bh, int create);
2436 int ext4_walk_page_buffers(handle_t *handle,
2437                            struct buffer_head *head,
2438                            unsigned from,
2439                            unsigned to,
2440                            int *partial,
2441                            int (*fn)(handle_t *handle,
2442                                      struct buffer_head *bh));
2443 int do_journal_get_write_access(handle_t *handle,
2444                                 struct buffer_head *bh);
2445 #define FALL_BACK_TO_NONDELALLOC 1
2446 #define CONVERT_INLINE_DATA      2
2447
2448 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2449 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2450 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2451 extern int  ext4_setattr(struct dentry *, struct iattr *);
2452 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2453 extern void ext4_evict_inode(struct inode *);
2454 extern void ext4_clear_inode(struct inode *);
2455 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2456 extern int  ext4_sync_inode(handle_t *, struct inode *);
2457 extern void ext4_dirty_inode(struct inode *, int);
2458 extern int ext4_change_inode_journal_flag(struct inode *, int);
2459 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2460 extern int ext4_inode_attach_jinode(struct inode *inode);
2461 extern int ext4_can_truncate(struct inode *inode);
2462 extern int ext4_truncate(struct inode *);
2463 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2464 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2465 extern void ext4_set_inode_flags(struct inode *);
2466 extern int ext4_alloc_da_blocks(struct inode *inode);
2467 extern void ext4_set_aops(struct inode *inode);
2468 extern int ext4_writepage_trans_blocks(struct inode *);
2469 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2470 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2471                              loff_t lstart, loff_t lend);
2472 extern int ext4_page_mkwrite(struct vm_fault *vmf);
2473 extern int ext4_filemap_fault(struct vm_fault *vmf);
2474 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2475 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2476 extern void ext4_da_update_reserve_space(struct inode *inode,
2477                                         int used, int quota_claim);
2478 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2479                               ext4_fsblk_t pblk, ext4_lblk_t len);
2480
2481 /* indirect.c */
2482 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2483                                 struct ext4_map_blocks *map, int flags);
2484 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2485 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2486 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2487 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2488                                  ext4_lblk_t start, ext4_lblk_t end);
2489
2490 /* ioctl.c */
2491 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2492 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2493
2494 /* migrate.c */
2495 extern int ext4_ext_migrate(struct inode *);
2496 extern int ext4_ind_migrate(struct inode *inode);
2497
2498 /* namei.c */
2499 extern int ext4_dirent_csum_verify(struct inode *inode,
2500                                    struct ext4_dir_entry *dirent);
2501 extern int ext4_orphan_add(handle_t *, struct inode *);
2502 extern int ext4_orphan_del(handle_t *, struct inode *);
2503 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2504                                 __u32 start_minor_hash, __u32 *next_hash);
2505 extern int ext4_search_dir(struct buffer_head *bh,
2506                            char *search_buf,
2507                            int buf_size,
2508                            struct inode *dir,
2509                            struct ext4_filename *fname,
2510                            unsigned int offset,
2511                            struct ext4_dir_entry_2 **res_dir);
2512 extern int ext4_generic_delete_entry(handle_t *handle,
2513                                      struct inode *dir,
2514                                      struct ext4_dir_entry_2 *de_del,
2515                                      struct buffer_head *bh,
2516                                      void *entry_buf,
2517                                      int buf_size,
2518                                      int csum_size);
2519 extern bool ext4_empty_dir(struct inode *inode);
2520
2521 /* resize.c */
2522 extern int ext4_group_add(struct super_block *sb,
2523                                 struct ext4_new_group_data *input);
2524 extern int ext4_group_extend(struct super_block *sb,
2525                                 struct ext4_super_block *es,
2526                                 ext4_fsblk_t n_blocks_count);
2527 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2528
2529 /* super.c */
2530 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2531 extern int ext4_calculate_overhead(struct super_block *sb);
2532 extern void ext4_superblock_csum_set(struct super_block *sb);
2533 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2534 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2535 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2536                                     ext4_group_t ngroup);
2537 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2538                                      char nbuf[16]);
2539 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2540                                              ext4_group_t block_group,
2541                                              unsigned int flags);
2542
2543 extern __printf(4, 5)
2544 void __ext4_error(struct super_block *, const char *, unsigned int,
2545                   const char *, ...);
2546 extern __printf(5, 6)
2547 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2548                       const char *, ...);
2549 extern __printf(5, 6)
2550 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2551                      const char *, ...);
2552 extern void __ext4_std_error(struct super_block *, const char *,
2553                              unsigned int, int);
2554 extern __printf(4, 5)
2555 void __ext4_abort(struct super_block *, const char *, unsigned int,
2556                   const char *, ...);
2557 extern __printf(4, 5)
2558 void __ext4_warning(struct super_block *, const char *, unsigned int,
2559                     const char *, ...);
2560 extern __printf(4, 5)
2561 void __ext4_warning_inode(const struct inode *inode, const char *function,
2562                           unsigned int line, const char *fmt, ...);
2563 extern __printf(3, 4)
2564 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2565 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2566                            const char *, unsigned int, const char *);
2567 extern __printf(7, 8)
2568 void __ext4_grp_locked_error(const char *, unsigned int,
2569                              struct super_block *, ext4_group_t,
2570                              unsigned long, ext4_fsblk_t,
2571                              const char *, ...);
2572
2573 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2574         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2575
2576 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
2577         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2578
2579 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
2580         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2581
2582 #ifdef CONFIG_PRINTK
2583
2584 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
2585         __ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2586 #define ext4_error_file(file, func, line, block, fmt, ...)              \
2587         __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2588 #define ext4_error(sb, fmt, ...)                                        \
2589         __ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2590 #define ext4_abort(sb, fmt, ...)                                        \
2591         __ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2592 #define ext4_warning(sb, fmt, ...)                                      \
2593         __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2594 #define ext4_warning_inode(inode, fmt, ...)                             \
2595         __ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2596 #define ext4_msg(sb, level, fmt, ...)                           \
2597         __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2598 #define dump_mmp_msg(sb, mmp, msg)                                      \
2599         __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2600 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
2601         __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2602                                 fmt, ##__VA_ARGS__)
2603
2604 #else
2605
2606 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
2607 do {                                                                    \
2608         no_printk(fmt, ##__VA_ARGS__);                                  \
2609         __ext4_error_inode(inode, "", 0, block, " ");                   \
2610 } while (0)
2611 #define ext4_error_file(file, func, line, block, fmt, ...)              \
2612 do {                                                                    \
2613         no_printk(fmt, ##__VA_ARGS__);                                  \
2614         __ext4_error_file(file, "", 0, block, " ");                     \
2615 } while (0)
2616 #define ext4_error(sb, fmt, ...)                                        \
2617 do {                                                                    \
2618         no_printk(fmt, ##__VA_ARGS__);                                  \
2619         __ext4_error(sb, "", 0, " ");                                   \
2620 } while (0)
2621 #define ext4_abort(sb, fmt, ...)                                        \
2622 do {                                                                    \
2623         no_printk(fmt, ##__VA_ARGS__);                                  \
2624         __ext4_abort(sb, "", 0, " ");                                   \
2625 } while (0)
2626 #define ext4_warning(sb, fmt, ...)                                      \
2627 do {                                                                    \
2628         no_printk(fmt, ##__VA_ARGS__);                                  \
2629         __ext4_warning(sb, "", 0, " ");                                 \
2630 } while (0)
2631 #define ext4_warning_inode(inode, fmt, ...)                             \
2632 do {                                                                    \
2633         no_printk(fmt, ##__VA_ARGS__);                                  \
2634         __ext4_warning_inode(inode, "", 0, " ");                        \
2635 } while (0)
2636 #define ext4_msg(sb, level, fmt, ...)                                   \
2637 do {                                                                    \
2638         no_printk(fmt, ##__VA_ARGS__);                                  \
2639         __ext4_msg(sb, "", " ");                                        \
2640 } while (0)
2641 #define dump_mmp_msg(sb, mmp, msg)                                      \
2642         __dump_mmp_msg(sb, mmp, "", 0, "")
2643 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
2644 do {                                                                    \
2645         no_printk(fmt, ##__VA_ARGS__);                          \
2646         __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");       \
2647 } while (0)
2648
2649 #endif
2650
2651 extern void ext4_update_dynamic_rev(struct super_block *sb);
2652 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2653                                         __u32 compat);
2654 extern int ext4_update_rocompat_feature(handle_t *handle,
2655                                         struct super_block *sb, __u32 rocompat);
2656 extern int ext4_update_incompat_feature(handle_t *handle,
2657                                         struct super_block *sb, __u32 incompat);
2658 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2659                                       struct ext4_group_desc *bg);
2660 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2661                                       struct ext4_group_desc *bg);
2662 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2663                                      struct ext4_group_desc *bg);
2664 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2665                                       struct ext4_group_desc *bg);
2666 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2667                                  struct ext4_group_desc *bg);
2668 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2669                                 struct ext4_group_desc *bg);
2670 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2671                                    struct ext4_group_desc *bg);
2672 extern void ext4_block_bitmap_set(struct super_block *sb,
2673                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2674 extern void ext4_inode_bitmap_set(struct super_block *sb,
2675                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2676 extern void ext4_inode_table_set(struct super_block *sb,
2677                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2678 extern void ext4_free_group_clusters_set(struct super_block *sb,
2679                                          struct ext4_group_desc *bg,
2680                                          __u32 count);
2681 extern void ext4_free_inodes_set(struct super_block *sb,
2682                                 struct ext4_group_desc *bg, __u32 count);
2683 extern void ext4_used_dirs_set(struct super_block *sb,
2684                                 struct ext4_group_desc *bg, __u32 count);
2685 extern void ext4_itable_unused_set(struct super_block *sb,
2686                                    struct ext4_group_desc *bg, __u32 count);
2687 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2688                                        struct ext4_group_desc *gdp);
2689 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2690                                      struct ext4_group_desc *gdp);
2691 extern int ext4_register_li_request(struct super_block *sb,
2692                                     ext4_group_t first_not_zeroed);
2693
2694 static inline int ext4_has_metadata_csum(struct super_block *sb)
2695 {
2696         WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2697                      !EXT4_SB(sb)->s_chksum_driver);
2698
2699         return ext4_has_feature_metadata_csum(sb) &&
2700                (EXT4_SB(sb)->s_chksum_driver != NULL);
2701 }
2702
2703 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2704 {
2705         return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2706 }
2707
2708 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2709 {
2710         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2711                 le32_to_cpu(es->s_blocks_count_lo);
2712 }
2713
2714 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2715 {
2716         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2717                 le32_to_cpu(es->s_r_blocks_count_lo);
2718 }
2719
2720 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2721 {
2722         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2723                 le32_to_cpu(es->s_free_blocks_count_lo);
2724 }
2725
2726 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2727                                          ext4_fsblk_t blk)
2728 {
2729         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2730         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2731 }
2732
2733 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2734                                               ext4_fsblk_t blk)
2735 {
2736         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2737         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2738 }
2739
2740 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2741                                            ext4_fsblk_t blk)
2742 {
2743         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2744         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2745 }
2746
2747 static inline loff_t ext4_isize(struct super_block *sb,
2748                                 struct ext4_inode *raw_inode)
2749 {
2750         if (ext4_has_feature_largedir(sb) ||
2751             S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2752                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2753                         le32_to_cpu(raw_inode->i_size_lo);
2754
2755         return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2756 }
2757
2758 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2759 {
2760         raw_inode->i_size_lo = cpu_to_le32(i_size);
2761         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2762 }
2763
2764 static inline
2765 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2766                                             ext4_group_t group)
2767 {
2768          struct ext4_group_info ***grp_info;
2769          long indexv, indexh;
2770          BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2771          grp_info = EXT4_SB(sb)->s_group_info;
2772          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2773          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2774          return grp_info[indexv][indexh];
2775 }
2776
2777 /*
2778  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2779  * the locking protocol documented in the comments of ext4_group_add()
2780  * in resize.c
2781  */
2782 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2783 {
2784         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2785
2786         smp_rmb();
2787         return ngroups;
2788 }
2789
2790 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2791                                              ext4_group_t block_group)
2792 {
2793         return block_group >> sbi->s_log_groups_per_flex;
2794 }
2795
2796 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2797 {
2798         return 1 << sbi->s_log_groups_per_flex;
2799 }
2800
2801 #define ext4_std_error(sb, errno)                               \
2802 do {                                                            \
2803         if ((errno))                                            \
2804                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2805 } while (0)
2806
2807 #ifdef CONFIG_SMP
2808 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2809  * counters. So we need to make sure we have free clusters more
2810  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2811  */
2812 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2813 #else
2814 #define EXT4_FREECLUSTERS_WATERMARK 0
2815 #endif
2816
2817 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2818 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2819 {
2820         WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2821                      !inode_is_locked(inode));
2822         down_write(&EXT4_I(inode)->i_data_sem);
2823         if (newsize > EXT4_I(inode)->i_disksize)
2824                 EXT4_I(inode)->i_disksize = newsize;
2825         up_write(&EXT4_I(inode)->i_data_sem);
2826 }
2827
2828 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2829 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2830 {
2831         int changed = 0;
2832
2833         if (newsize > inode->i_size) {
2834                 i_size_write(inode, newsize);
2835                 changed = 1;
2836         }
2837         if (newsize > EXT4_I(inode)->i_disksize) {
2838                 ext4_update_i_disksize(inode, newsize);
2839                 changed |= 2;
2840         }
2841         return changed;
2842 }
2843
2844 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2845                                       loff_t len);
2846
2847 struct ext4_group_info {
2848         unsigned long   bb_state;
2849         struct rb_root  bb_free_root;
2850         ext4_grpblk_t   bb_first_free;  /* first free block */
2851         ext4_grpblk_t   bb_free;        /* total free blocks */
2852         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2853         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2854         struct          list_head bb_prealloc_list;
2855 #ifdef DOUBLE_CHECK
2856         void            *bb_bitmap;
2857 #endif
2858         struct rw_semaphore alloc_sem;
2859         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2860                                          * regions, index is order.
2861                                          * bb_counters[3] = 5 means
2862                                          * 5 free 8-block regions. */
2863 };
2864
2865 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2866 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2867 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT     2
2868 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT     3
2869 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT         \
2870         (1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
2871 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT         \
2872         (1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
2873
2874 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2875         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2876 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)        \
2877         (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2878 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)        \
2879         (test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2880
2881 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2882         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2883 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2884         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2885 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2886         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2887
2888 #define EXT4_MAX_CONTENTION             8
2889 #define EXT4_CONTENTION_THRESHOLD       2
2890
2891 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2892                                               ext4_group_t group)
2893 {
2894         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2895 }
2896
2897 /*
2898  * Returns true if the filesystem is busy enough that attempts to
2899  * access the block group locks has run into contention.
2900  */
2901 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2902 {
2903         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2904 }
2905
2906 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2907 {
2908         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2909         if (spin_trylock(lock))
2910                 /*
2911                  * We're able to grab the lock right away, so drop the
2912                  * lock contention counter.
2913                  */
2914                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2915         else {
2916                 /*
2917                  * The lock is busy, so bump the contention counter,
2918                  * and then wait on the spin lock.
2919                  */
2920                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2921                                   EXT4_MAX_CONTENTION);
2922                 spin_lock(lock);
2923         }
2924 }
2925
2926 static inline void ext4_unlock_group(struct super_block *sb,
2927                                         ext4_group_t group)
2928 {
2929         spin_unlock(ext4_group_lock_ptr(sb, group));
2930 }
2931
2932 /*
2933  * Block validity checking
2934  */
2935 #define ext4_check_indirect_blockref(inode, bh)                         \
2936         ext4_check_blockref(__func__, __LINE__, inode,                  \
2937                             (__le32 *)(bh)->b_data,                     \
2938                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2939
2940 #define ext4_ind_check_inode(inode)                                     \
2941         ext4_check_blockref(__func__, __LINE__, inode,                  \
2942                             EXT4_I(inode)->i_data,                      \
2943                             EXT4_NDIR_BLOCKS)
2944
2945 /*
2946  * Inodes and files operations
2947  */
2948
2949 /* dir.c */
2950 extern const struct file_operations ext4_dir_operations;
2951
2952 /* file.c */
2953 extern const struct inode_operations ext4_file_inode_operations;
2954 extern const struct file_operations ext4_file_operations;
2955 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2956
2957 /* inline.c */
2958 extern int ext4_get_max_inline_size(struct inode *inode);
2959 extern int ext4_find_inline_data_nolock(struct inode *inode);
2960 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2961                                  unsigned int len);
2962 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2963
2964 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2965 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2966                                          struct inode *inode,
2967                                          loff_t pos, unsigned len,
2968                                          unsigned flags,
2969                                          struct page **pagep);
2970 extern int ext4_write_inline_data_end(struct inode *inode,
2971                                       loff_t pos, unsigned len,
2972                                       unsigned copied,
2973                                       struct page *page);
2974 extern struct buffer_head *
2975 ext4_journalled_write_inline_data(struct inode *inode,
2976                                   unsigned len,
2977                                   struct page *page);
2978 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2979                                            struct inode *inode,
2980                                            loff_t pos, unsigned len,
2981                                            unsigned flags,
2982                                            struct page **pagep,
2983                                            void **fsdata);
2984 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2985                                          unsigned len, unsigned copied,
2986                                          struct page *page);
2987 extern int ext4_try_add_inline_entry(handle_t *handle,
2988                                      struct ext4_filename *fname,
2989                                      struct inode *dir, struct inode *inode);
2990 extern int ext4_try_create_inline_dir(handle_t *handle,
2991                                       struct inode *parent,
2992                                       struct inode *inode);
2993 extern int ext4_read_inline_dir(struct file *filp,
2994                                 struct dir_context *ctx,
2995                                 int *has_inline_data);
2996 extern int htree_inlinedir_to_tree(struct file *dir_file,
2997                                    struct inode *dir, ext4_lblk_t block,
2998                                    struct dx_hash_info *hinfo,
2999                                    __u32 start_hash, __u32 start_minor_hash,
3000                                    int *has_inline_data);
3001 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3002                                         struct ext4_filename *fname,
3003                                         struct ext4_dir_entry_2 **res_dir,
3004                                         int *has_inline_data);
3005 extern int ext4_delete_inline_entry(handle_t *handle,
3006                                     struct inode *dir,
3007                                     struct ext4_dir_entry_2 *de_del,
3008                                     struct buffer_head *bh,
3009                                     int *has_inline_data);
3010 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3011 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3012                                         struct ext4_dir_entry_2 **parent_de,
3013                                         int *retval);
3014 extern int ext4_inline_data_fiemap(struct inode *inode,
3015                                    struct fiemap_extent_info *fieinfo,
3016                                    int *has_inline, __u64 start, __u64 len);
3017
3018 struct iomap;
3019 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3020
3021 extern int ext4_try_to_evict_inline_data(handle_t *handle,
3022                                          struct inode *inode,
3023                                          int needed);
3024 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3025
3026 extern int ext4_convert_inline_data(struct inode *inode);
3027
3028 static inline int ext4_has_inline_data(struct inode *inode)
3029 {
3030         return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3031                EXT4_I(inode)->i_inline_off;
3032 }
3033
3034 /* namei.c */
3035 extern const struct inode_operations ext4_dir_inode_operations;
3036 extern const struct inode_operations ext4_special_inode_operations;
3037 extern struct dentry *ext4_get_parent(struct dentry *child);
3038 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3039                                  struct ext4_dir_entry_2 *de,
3040                                  int blocksize, int csum_size,
3041                                  unsigned int parent_ino, int dotdot_real_len);
3042 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3043                                    unsigned int blocksize);
3044 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3045                                          struct inode *inode,
3046                                          struct buffer_head *bh);
3047 #define S_SHIFT 12
3048 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3049         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
3050         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
3051         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
3052         [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
3053         [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
3054         [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
3055         [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
3056 };
3057
3058 static inline void ext4_set_de_type(struct super_block *sb,
3059                                 struct ext4_dir_entry_2 *de,
3060                                 umode_t mode) {
3061         if (ext4_has_feature_filetype(sb))
3062                 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3063 }
3064
3065 /* readpages.c */
3066 extern int ext4_mpage_readpages(struct address_space *mapping,
3067                                 struct list_head *pages, struct page *page,
3068                                 unsigned nr_pages);
3069
3070 /* symlink.c */
3071 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3072 extern const struct inode_operations ext4_symlink_inode_operations;
3073 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3074
3075 /* sysfs.c */
3076 extern int ext4_register_sysfs(struct super_block *sb);
3077 extern void ext4_unregister_sysfs(struct super_block *sb);
3078 extern int __init ext4_init_sysfs(void);
3079 extern void ext4_exit_sysfs(void);
3080
3081 /* block_validity */
3082 extern void ext4_release_system_zone(struct super_block *sb);
3083 extern int ext4_setup_system_zone(struct super_block *sb);
3084 extern int __init ext4_init_system_zone(void);
3085 extern void ext4_exit_system_zone(void);
3086 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3087                                  ext4_fsblk_t start_blk,
3088                                  unsigned int count);
3089 extern int ext4_check_blockref(const char *, unsigned int,
3090                                struct inode *, __le32 *, unsigned int);
3091
3092 /* extents.c */
3093 struct ext4_ext_path;
3094 struct ext4_extent;
3095
3096 /*
3097  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3098  * __le32.
3099  */
3100 #define EXT_MAX_BLOCKS  0xffffffff
3101
3102 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3103 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3104 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3105 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3106                                struct ext4_map_blocks *map, int flags);
3107 extern int ext4_ext_truncate(handle_t *, struct inode *);
3108 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3109                                  ext4_lblk_t end);
3110 extern void ext4_ext_init(struct super_block *);
3111 extern void ext4_ext_release(struct super_block *);
3112 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3113                           loff_t len);
3114 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3115                                           loff_t offset, ssize_t len);
3116 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3117                            struct ext4_map_blocks *map, int flags);
3118 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3119                                          ext4_lblk_t lblocks);
3120 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3121                                                    int num,
3122                                                    struct ext4_ext_path *path);
3123 extern int ext4_can_extents_be_merged(struct inode *inode,
3124                                       struct ext4_extent *ex1,
3125                                       struct ext4_extent *ex2);
3126 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3127                                   struct ext4_ext_path **,
3128                                   struct ext4_extent *, int);
3129 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3130                                               struct ext4_ext_path **,
3131                                               int flags);
3132 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3133 extern int ext4_ext_check_inode(struct inode *inode);
3134 extern int ext4_find_delalloc_range(struct inode *inode,
3135                                     ext4_lblk_t lblk_start,
3136                                     ext4_lblk_t lblk_end);
3137 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3138 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3139 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3140                         __u64 start, __u64 len);
3141 extern int ext4_ext_precache(struct inode *inode);
3142 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3143 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3144 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3145                                 struct inode *inode2, ext4_lblk_t lblk1,
3146                              ext4_lblk_t lblk2,  ext4_lblk_t count,
3147                              int mark_unwritten,int *err);
3148
3149 /* move_extent.c */
3150 extern void ext4_double_down_write_data_sem(struct inode *first,
3151                                             struct inode *second);
3152 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3153                                           struct inode *donor_inode);
3154 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3155                              __u64 start_orig, __u64 start_donor,
3156                              __u64 len, __u64 *moved_len);
3157
3158 /* page-io.c */
3159 extern int __init ext4_init_pageio(void);
3160 extern void ext4_exit_pageio(void);
3161 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3162 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3163 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3164 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3165 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3166                                 struct writeback_control *wbc);
3167 extern void ext4_end_io_rsv_work(struct work_struct *work);
3168 extern void ext4_io_submit(struct ext4_io_submit *io);
3169 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3170                                struct page *page,
3171                                int len,
3172                                struct writeback_control *wbc,
3173                                bool keep_towrite);
3174
3175 /* mmp.c */
3176 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3177
3178 /*
3179  * Add new method to test whether block and inode bitmaps are properly
3180  * initialized. With uninit_bg reading the block from disk is not enough
3181  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3182  */
3183 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3184
3185 static inline int bitmap_uptodate(struct buffer_head *bh)
3186 {
3187         return (buffer_uptodate(bh) &&
3188                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3189 }
3190 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3191 {
3192         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3193 }
3194
3195 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
3196
3197 /* For ioend & aio unwritten conversion wait queues */
3198 #define EXT4_WQ_HASH_SZ         37
3199 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3200                                             EXT4_WQ_HASH_SZ])
3201 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3202
3203 extern int ext4_resize_begin(struct super_block *sb);
3204 extern void ext4_resize_end(struct super_block *sb);
3205
3206 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3207                                               struct ext4_io_end *io_end)
3208 {
3209         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3210                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
3211                 atomic_inc(&EXT4_I(inode)->i_unwritten);
3212         }
3213 }
3214
3215 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3216 {
3217         struct inode *inode = io_end->inode;
3218
3219         if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3220                 io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3221                 /* Wake up anyone waiting on unwritten extent conversion */
3222                 if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3223                         wake_up_all(ext4_ioend_wq(inode));
3224         }
3225 }
3226
3227 extern const struct iomap_ops ext4_iomap_ops;
3228
3229 #endif  /* __KERNEL__ */
3230
3231 #define EFSBADCRC       EBADMSG         /* Bad CRC detected */
3232 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
3233
3234 #endif  /* _EXT4_H */