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TOMOYO Linux Cross Reference
Linux/fs/ext4/ext4.h

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  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                 (raw_inode)->xtime ## _extra =                                 \
825                                 ext4_encode_extra_time(&(inode)->xtime);       \
826 } while (0)
827 
828 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
829 do {                                                                           \
830         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
831                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
832         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
833                 (raw_inode)->xtime ## _extra =                                 \
834                                 ext4_encode_extra_time(&(einode)->xtime);      \
835 } while (0)
836 
837 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
838 do {                                                                           \
839         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
840         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
841                 ext4_decode_extra_time(&(inode)->xtime,                        \
842                                        raw_inode->xtime ## _extra);            \
843         else                                                                   \
844                 (inode)->xtime.tv_nsec = 0;                                    \
845 } while (0)
846 
847 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
848 do {                                                                           \
849         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
850                 (einode)->xtime.tv_sec =                                       \
851                         (signed)le32_to_cpu((raw_inode)->xtime);               \
852         else                                                                   \
853                 (einode)->xtime.tv_sec = 0;                                    \
854         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
855                 ext4_decode_extra_time(&(einode)->xtime,                       \
856                                        raw_inode->xtime ## _extra);            \
857         else                                                                   \
858                 (einode)->xtime.tv_nsec = 0;                                   \
859 } while (0)
860 
861 #define i_disk_version osd1.linux1.l_i_version
862 
863 #if defined(__KERNEL__) || defined(__linux__)
864 #define i_reserved1     osd1.linux1.l_i_reserved1
865 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
866 #define i_blocks_high   osd2.linux2.l_i_blocks_high
867 #define i_uid_low       i_uid
868 #define i_gid_low       i_gid
869 #define i_uid_high      osd2.linux2.l_i_uid_high
870 #define i_gid_high      osd2.linux2.l_i_gid_high
871 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
872 
873 #elif defined(__GNU__)
874 
875 #define i_translator    osd1.hurd1.h_i_translator
876 #define i_uid_high      osd2.hurd2.h_i_uid_high
877 #define i_gid_high      osd2.hurd2.h_i_gid_high
878 #define i_author        osd2.hurd2.h_i_author
879 
880 #elif defined(__masix__)
881 
882 #define i_reserved1     osd1.masix1.m_i_reserved1
883 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
884 #define i_reserved2     osd2.masix2.m_i_reserved2
885 
886 #endif /* defined(__KERNEL__) || defined(__linux__) */
887 
888 #include "extents_status.h"
889 
890 /*
891  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
892  *
893  * These are needed to avoid lockdep false positives when we need to
894  * allocate blocks to the quota inode during ext4_map_blocks(), while
895  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
896  * do quota tracking for the quota inode, this avoids deadlock (as
897  * well as infinite recursion, since it isn't turtles all the way
898  * down...)
899  *
900  *  I_DATA_SEM_NORMAL - Used for most inodes
901  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
902  *                        where the second inode has larger inode number
903  *                        than the first
904  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
905  */
906 enum {
907         I_DATA_SEM_NORMAL = 0,
908         I_DATA_SEM_OTHER,
909         I_DATA_SEM_QUOTA,
910 };
911 
912 
913 /*
914  * fourth extended file system inode data in memory
915  */
916 struct ext4_inode_info {
917         __le32  i_data[15];     /* unconverted */
918         __u32   i_dtime;
919         ext4_fsblk_t    i_file_acl;
920 
921         /*
922          * i_block_group is the number of the block group which contains
923          * this file's inode.  Constant across the lifetime of the inode,
924          * it is used for making block allocation decisions - we try to
925          * place a file's data blocks near its inode block, and new inodes
926          * near to their parent directory's inode.
927          */
928         ext4_group_t    i_block_group;
929         ext4_lblk_t     i_dir_start_lookup;
930 #if (BITS_PER_LONG < 64)
931         unsigned long   i_state_flags;          /* Dynamic state flags */
932 #endif
933         unsigned long   i_flags;
934 
935         /*
936          * Extended attributes can be read independently of the main file
937          * data. Taking i_mutex even when reading would cause contention
938          * between readers of EAs and writers of regular file data, so
939          * instead we synchronize on xattr_sem when reading or changing
940          * EAs.
941          */
942         struct rw_semaphore xattr_sem;
943 
944         struct list_head i_orphan;      /* unlinked but open inodes */
945 
946         /*
947          * i_disksize keeps track of what the inode size is ON DISK, not
948          * in memory.  During truncate, i_size is set to the new size by
949          * the VFS prior to calling ext4_truncate(), but the filesystem won't
950          * set i_disksize to 0 until the truncate is actually under way.
951          *
952          * The intent is that i_disksize always represents the blocks which
953          * are used by this file.  This allows recovery to restart truncate
954          * on orphans if we crash during truncate.  We actually write i_disksize
955          * into the on-disk inode when writing inodes out, instead of i_size.
956          *
957          * The only time when i_disksize and i_size may be different is when
958          * a truncate is in progress.  The only things which change i_disksize
959          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
960          */
961         loff_t  i_disksize;
962 
963         /*
964          * i_data_sem is for serialising ext4_truncate() against
965          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
966          * data tree are chopped off during truncate. We can't do that in
967          * ext4 because whenever we perform intermediate commits during
968          * truncate, the inode and all the metadata blocks *must* be in a
969          * consistent state which allows truncation of the orphans to restart
970          * during recovery.  Hence we must fix the get_block-vs-truncate race
971          * by other means, so we have i_data_sem.
972          */
973         struct rw_semaphore i_data_sem;
974         /*
975          * i_mmap_sem is for serializing page faults with truncate / punch hole
976          * operations. We have to make sure that new page cannot be faulted in
977          * a section of the inode that is being punched. We cannot easily use
978          * i_data_sem for this since we need protection for the whole punch
979          * operation and i_data_sem ranks below transaction start so we have
980          * to occasionally drop it.
981          */
982         struct rw_semaphore i_mmap_sem;
983         struct inode vfs_inode;
984         struct jbd2_inode *jinode;
985 
986         spinlock_t i_raw_lock;  /* protects updates to the raw inode */
987 
988         /*
989          * File creation time. Its function is same as that of
990          * struct timespec i_{a,c,m}time in the generic inode.
991          */
992         struct timespec i_crtime;
993 
994         /* mballoc */
995         struct list_head i_prealloc_list;
996         spinlock_t i_prealloc_lock;
997 
998         /* extents status tree */
999         struct ext4_es_tree i_es_tree;
1000         rwlock_t i_es_lock;
1001         struct list_head i_es_list;
1002         unsigned int i_es_all_nr;       /* protected by i_es_lock */
1003         unsigned int i_es_shk_nr;       /* protected by i_es_lock */
1004         ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
1005                                            extents to shrink. Protected by
1006                                            i_es_lock  */
1007 
1008         /* ialloc */
1009         ext4_group_t    i_last_alloc_group;
1010 
1011         /* allocation reservation info for delalloc */
1012         /* In case of bigalloc, this refer to clusters rather than blocks */
1013         unsigned int i_reserved_data_blocks;
1014         ext4_lblk_t i_da_metadata_calc_last_lblock;
1015         int i_da_metadata_calc_len;
1016 
1017         /* on-disk additional length */
1018         __u16 i_extra_isize;
1019 
1020         /* Indicate the inline data space. */
1021         u16 i_inline_off;
1022         u16 i_inline_size;
1023 
1024 #ifdef CONFIG_QUOTA
1025         /* quota space reservation, managed internally by quota code */
1026         qsize_t i_reserved_quota;
1027 #endif
1028 
1029         /* Lock protecting lists below */
1030         spinlock_t i_completed_io_lock;
1031         /*
1032          * Completed IOs that need unwritten extents handling and have
1033          * transaction reserved
1034          */
1035         struct list_head i_rsv_conversion_list;
1036         struct work_struct i_rsv_conversion_work;
1037         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1038 
1039         spinlock_t i_block_reservation_lock;
1040 
1041         /*
1042          * Transactions that contain inode's metadata needed to complete
1043          * fsync and fdatasync, respectively.
1044          */
1045         tid_t i_sync_tid;
1046         tid_t i_datasync_tid;
1047 
1048 #ifdef CONFIG_QUOTA
1049         struct dquot *i_dquot[MAXQUOTAS];
1050 #endif
1051 
1052         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1053         __u32 i_csum_seed;
1054 
1055         kprojid_t i_projid;
1056 };
1057 
1058 /*
1059  * File system states
1060  */
1061 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
1062 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
1063 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
1064 
1065 /*
1066  * Misc. filesystem flags
1067  */
1068 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
1069 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
1070 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
1071 
1072 /*
1073  * Mount flags set via mount options or defaults
1074  */
1075 #define EXT4_MOUNT_NO_MBCACHE           0x00001 /* Do not use mbcache */
1076 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
1077 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
1078 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
1079 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
1080 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
1081 #define EXT4_MOUNT_ERRORS_MASK          0x00070
1082 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
1083 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
1084 #ifdef CONFIG_FS_DAX
1085 #define EXT4_MOUNT_DAX                  0x00200 /* Direct Access */
1086 #else
1087 #define EXT4_MOUNT_DAX                  0
1088 #endif
1089 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
1090 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
1091 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
1092 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
1093 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
1094 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
1095 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
1096 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
1097 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
1098 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
1099 #define EXT4_MOUNT_QUOTA                0x40000 /* Some quota option set */
1100 #define EXT4_MOUNT_USRQUOTA             0x80000 /* "old" user quota,
1101                                                  * enable enforcement for hidden
1102                                                  * quota files */
1103 #define EXT4_MOUNT_GRPQUOTA             0x100000 /* "old" group quota, enable
1104                                                   * enforcement for hidden quota
1105                                                   * files */
1106 #define EXT4_MOUNT_PRJQUOTA             0x200000 /* Enable project quota
1107                                                   * enforcement */
1108 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
1109 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
1110 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
1111 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
1112 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
1113 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
1114 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
1115 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
1116 
1117 /*
1118  * Mount flags set either automatically (could not be set by mount option)
1119  * based on per file system feature or property or in special cases such as
1120  * distinguishing between explicit mount option definition and default.
1121  */
1122 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1123                                                       specified delalloc */
1124 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
1125                                                       size of blocksize * 8
1126                                                       blocks */
1127 #define EXT4_MOUNT2_HURD_COMPAT         0x00000004 /* Support HURD-castrated
1128                                                       file systems */
1129 
1130 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM   0x00000008 /* User explicitly
1131                                                 specified journal checksum */
1132 
1133 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1134                                                 ~EXT4_MOUNT_##opt
1135 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1136                                                 EXT4_MOUNT_##opt
1137 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1138                                          EXT4_MOUNT_##opt)
1139 
1140 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1141                                                 ~EXT4_MOUNT2_##opt
1142 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1143                                                 EXT4_MOUNT2_##opt
1144 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1145                                          EXT4_MOUNT2_##opt)
1146 
1147 #define ext4_test_and_set_bit           __test_and_set_bit_le
1148 #define ext4_set_bit                    __set_bit_le
1149 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1150 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1151 #define ext4_clear_bit                  __clear_bit_le
1152 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1153 #define ext4_test_bit                   test_bit_le
1154 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1155 #define ext4_find_next_bit              find_next_bit_le
1156 
1157 extern void ext4_set_bits(void *bm, int cur, int len);
1158 
1159 /*
1160  * Maximal mount counts between two filesystem checks
1161  */
1162 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1163 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1164 
1165 /*
1166  * Behaviour when detecting errors
1167  */
1168 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1169 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1170 #define EXT4_ERRORS_PANIC               3       /* Panic */
1171 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1172 
1173 /* Metadata checksum algorithm codes */
1174 #define EXT4_CRC32C_CHKSUM              1
1175 
1176 /*
1177  * Structure of the super block
1178  */
1179 struct ext4_super_block {
1180 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1181         __le32  s_blocks_count_lo;      /* Blocks count */
1182         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1183         __le32  s_free_blocks_count_lo; /* Free blocks count */
1184 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1185         __le32  s_first_data_block;     /* First Data Block */
1186         __le32  s_log_block_size;       /* Block size */
1187         __le32  s_log_cluster_size;     /* Allocation cluster size */
1188 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1189         __le32  s_clusters_per_group;   /* # Clusters per group */
1190         __le32  s_inodes_per_group;     /* # Inodes per group */
1191         __le32  s_mtime;                /* Mount time */
1192 /*30*/  __le32  s_wtime;                /* Write time */
1193         __le16  s_mnt_count;            /* Mount count */
1194         __le16  s_max_mnt_count;        /* Maximal mount count */
1195         __le16  s_magic;                /* Magic signature */
1196         __le16  s_state;                /* File system state */
1197         __le16  s_errors;               /* Behaviour when detecting errors */
1198         __le16  s_minor_rev_level;      /* minor revision level */
1199 /*40*/  __le32  s_lastcheck;            /* time of last check */
1200         __le32  s_checkinterval;        /* max. time between checks */
1201         __le32  s_creator_os;           /* OS */
1202         __le32  s_rev_level;            /* Revision level */
1203 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1204         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1205         /*
1206          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1207          *
1208          * Note: the difference between the compatible feature set and
1209          * the incompatible feature set is that if there is a bit set
1210          * in the incompatible feature set that the kernel doesn't
1211          * know about, it should refuse to mount the filesystem.
1212          *
1213          * e2fsck's requirements are more strict; if it doesn't know
1214          * about a feature in either the compatible or incompatible
1215          * feature set, it must abort and not try to meddle with
1216          * things it doesn't understand...
1217          */
1218         __le32  s_first_ino;            /* First non-reserved inode */
1219         __le16  s_inode_size;           /* size of inode structure */
1220         __le16  s_block_group_nr;       /* block group # of this superblock */
1221         __le32  s_feature_compat;       /* compatible feature set */
1222 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1223         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1224 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1225 /*78*/  char    s_volume_name[16];      /* volume name */
1226 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1227 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1228         /*
1229          * Performance hints.  Directory preallocation should only
1230          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1231          */
1232         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1233         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1234         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1235         /*
1236          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1237          */
1238 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1239 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1240         __le32  s_journal_dev;          /* device number of journal file */
1241         __le32  s_last_orphan;          /* start of list of inodes to delete */
1242         __le32  s_hash_seed[4];         /* HTREE hash seed */
1243         __u8    s_def_hash_version;     /* Default hash version to use */
1244         __u8    s_jnl_backup_type;
1245         __le16  s_desc_size;            /* size of group descriptor */
1246 /*100*/ __le32  s_default_mount_opts;
1247         __le32  s_first_meta_bg;        /* First metablock block group */
1248         __le32  s_mkfs_time;            /* When the filesystem was created */
1249         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1250         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1251 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1252         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1253         __le32  s_free_blocks_count_hi; /* Free blocks count */
1254         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1255         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1256         __le32  s_flags;                /* Miscellaneous flags */
1257         __le16  s_raid_stride;          /* RAID stride */
1258         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1259         __le64  s_mmp_block;            /* Block for multi-mount protection */
1260         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1261         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1262         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1263         __u8    s_encryption_level;     /* versioning level for encryption */
1264         __u8    s_reserved_pad;         /* Padding to next 32bits */
1265         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1266         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1267         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1268         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1269                                               snapshot's future use */
1270         __le32  s_snapshot_list;        /* inode number of the head of the
1271                                            on-disk snapshot list */
1272 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1273         __le32  s_error_count;          /* number of fs errors */
1274         __le32  s_first_error_time;     /* first time an error happened */
1275         __le32  s_first_error_ino;      /* inode involved in first error */
1276         __le64  s_first_error_block;    /* block involved of first error */
1277         __u8    s_first_error_func[32]; /* function where the error happened */
1278         __le32  s_first_error_line;     /* line number where error happened */
1279         __le32  s_last_error_time;      /* most recent time of an error */
1280         __le32  s_last_error_ino;       /* inode involved in last error */
1281         __le32  s_last_error_line;      /* line number where error happened */
1282         __le64  s_last_error_block;     /* block involved of last error */
1283         __u8    s_last_error_func[32];  /* function where the error happened */
1284 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1285         __u8    s_mount_opts[64];
1286         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1287         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1288         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1289         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
1290         __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
1291         __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
1292         __le32  s_lpf_ino;              /* Location of the lost+found inode */
1293         __le32  s_prj_quota_inum;       /* inode for tracking project quota */
1294         __le32  s_checksum_seed;        /* crc32c(uuid) if csum_seed set */
1295         __le32  s_reserved[98];         /* Padding to the end of the block */
1296         __le32  s_checksum;             /* crc32c(superblock) */
1297 };
1298 
1299 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1300 
1301 #ifdef __KERNEL__
1302 
1303 /*
1304  * run-time mount flags
1305  */
1306 #define EXT4_MF_MNTDIR_SAMPLED          0x0001
1307 #define EXT4_MF_FS_ABORTED              0x0002  /* Fatal error detected */
1308 #define EXT4_MF_TEST_DUMMY_ENCRYPTION   0x0004
1309 
1310 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1311 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1312                                                 EXT4_MF_TEST_DUMMY_ENCRYPTION))
1313 #else
1314 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1315 #endif
1316 
1317 /* Number of quota types we support */
1318 #define EXT4_MAXQUOTAS 3
1319 
1320 /*
1321  * fourth extended-fs super-block data in memory
1322  */
1323 struct ext4_sb_info {
1324         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1325         unsigned long s_inodes_per_block;/* Number of inodes per block */
1326         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1327         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1328         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1329         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1330         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1331         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1332         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1333         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1334         unsigned long s_overhead;  /* # of fs overhead clusters */
1335         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1336         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1337         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1338         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1339         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1340         struct buffer_head **s_group_desc;
1341         unsigned int s_mount_opt;
1342         unsigned int s_mount_opt2;
1343         unsigned int s_mount_flags;
1344         unsigned int s_def_mount_opt;
1345         ext4_fsblk_t s_sb_block;
1346         atomic64_t s_resv_clusters;
1347         kuid_t s_resuid;
1348         kgid_t s_resgid;
1349         unsigned short s_mount_state;
1350         unsigned short s_pad;
1351         int s_addr_per_block_bits;
1352         int s_desc_per_block_bits;
1353         int s_inode_size;
1354         int s_first_ino;
1355         unsigned int s_inode_readahead_blks;
1356         unsigned int s_inode_goal;
1357         u32 s_hash_seed[4];
1358         int s_def_hash_version;
1359         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1360         struct percpu_counter s_freeclusters_counter;
1361         struct percpu_counter s_freeinodes_counter;
1362         struct percpu_counter s_dirs_counter;
1363         struct percpu_counter s_dirtyclusters_counter;
1364         struct blockgroup_lock *s_blockgroup_lock;
1365         struct proc_dir_entry *s_proc;
1366         struct kobject s_kobj;
1367         struct completion s_kobj_unregister;
1368         struct super_block *s_sb;
1369 
1370         /* Journaling */
1371         struct journal_s *s_journal;
1372         struct list_head s_orphan;
1373         struct mutex s_orphan_lock;
1374         unsigned long s_ext4_flags;             /* Ext4 superblock flags */
1375         unsigned long s_commit_interval;
1376         u32 s_max_batch_time;
1377         u32 s_min_batch_time;
1378         struct block_device *journal_bdev;
1379 #ifdef CONFIG_QUOTA
1380         char *s_qf_names[EXT4_MAXQUOTAS];       /* Names of quota files with journalled quota */
1381         int s_jquota_fmt;                       /* Format of quota to use */
1382 #endif
1383         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1384         struct rb_root system_blks;
1385 
1386 #ifdef EXTENTS_STATS
1387         /* ext4 extents stats */
1388         unsigned long s_ext_min;
1389         unsigned long s_ext_max;
1390         unsigned long s_depth_max;
1391         spinlock_t s_ext_stats_lock;
1392         unsigned long s_ext_blocks;
1393         unsigned long s_ext_extents;
1394 #endif
1395 
1396         /* for buddy allocator */
1397         struct ext4_group_info ***s_group_info;
1398         struct inode *s_buddy_cache;
1399         spinlock_t s_md_lock;
1400         unsigned short *s_mb_offsets;
1401         unsigned int *s_mb_maxs;
1402         unsigned int s_group_info_size;
1403         unsigned int s_mb_free_pending;
1404         struct list_head s_freed_data_list;     /* List of blocks to be freed
1405                                                    after commit completed */
1406 
1407         /* tunables */
1408         unsigned long s_stripe;
1409         unsigned int s_mb_stream_request;
1410         unsigned int s_mb_max_to_scan;
1411         unsigned int s_mb_min_to_scan;
1412         unsigned int s_mb_stats;
1413         unsigned int s_mb_order2_reqs;
1414         unsigned int s_mb_group_prealloc;
1415         unsigned int s_max_dir_size_kb;
1416         /* where last allocation was done - for stream allocation */
1417         unsigned long s_mb_last_group;
1418         unsigned long s_mb_last_start;
1419 
1420         /* stats for buddy allocator */
1421         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1422         atomic_t s_bal_success; /* we found long enough chunks */
1423         atomic_t s_bal_allocated;       /* in blocks */
1424         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1425         atomic_t s_bal_goals;   /* goal hits */
1426         atomic_t s_bal_breaks;  /* too long searches */
1427         atomic_t s_bal_2orders; /* 2^order hits */
1428         spinlock_t s_bal_lock;
1429         unsigned long s_mb_buddies_generated;
1430         unsigned long long s_mb_generation_time;
1431         atomic_t s_mb_lost_chunks;
1432         atomic_t s_mb_preallocated;
1433         atomic_t s_mb_discarded;
1434         atomic_t s_lock_busy;
1435 
1436         /* locality groups */
1437         struct ext4_locality_group __percpu *s_locality_groups;
1438 
1439         /* for write statistics */
1440         unsigned long s_sectors_written_start;
1441         u64 s_kbytes_written;
1442 
1443         /* the size of zero-out chunk */
1444         unsigned int s_extent_max_zeroout_kb;
1445 
1446         unsigned int s_log_groups_per_flex;
1447         struct flex_groups *s_flex_groups;
1448         ext4_group_t s_flex_groups_allocated;
1449 
1450         /* workqueue for reserved extent conversions (buffered io) */
1451         struct workqueue_struct *rsv_conversion_wq;
1452 
1453         /* timer for periodic error stats printing */
1454         struct timer_list s_err_report;
1455 
1456         /* Lazy inode table initialization info */
1457         struct ext4_li_request *s_li_request;
1458         /* Wait multiplier for lazy initialization thread */
1459         unsigned int s_li_wait_mult;
1460 
1461         /* Kernel thread for multiple mount protection */
1462         struct task_struct *s_mmp_tsk;
1463 
1464         /* record the last minlen when FITRIM is called. */
1465         atomic_t s_last_trim_minblks;
1466 
1467         /* Reference to checksum algorithm driver via cryptoapi */
1468         struct crypto_shash *s_chksum_driver;
1469 
1470         /* Precomputed FS UUID checksum for seeding other checksums */
1471         __u32 s_csum_seed;
1472 
1473         /* Reclaim extents from extent status tree */
1474         struct shrinker s_es_shrinker;
1475         struct list_head s_es_list;     /* List of inodes with reclaimable extents */
1476         long s_es_nr_inode;
1477         struct ext4_es_stats s_es_stats;
1478         struct mb_cache *s_ea_block_cache;
1479         struct mb_cache *s_ea_inode_cache;
1480         spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1481 
1482         /* Ratelimit ext4 messages. */
1483         struct ratelimit_state s_err_ratelimit_state;
1484         struct ratelimit_state s_warning_ratelimit_state;
1485         struct ratelimit_state s_msg_ratelimit_state;
1486 
1487         /* Barrier between changing inodes' journal flags and writepages ops. */
1488         struct percpu_rw_semaphore s_journal_flag_rwsem;
1489         struct dax_device *s_daxdev;
1490 };
1491 
1492 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1493 {
1494         return sb->s_fs_info;
1495 }
1496 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1497 {
1498         return container_of(inode, struct ext4_inode_info, vfs_inode);
1499 }
1500 
1501 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1502 {
1503         return ino == EXT4_ROOT_INO ||
1504                 ino == EXT4_USR_QUOTA_INO ||
1505                 ino == EXT4_GRP_QUOTA_INO ||
1506                 ino == EXT4_BOOT_LOADER_INO ||
1507                 ino == EXT4_JOURNAL_INO ||
1508                 ino == EXT4_RESIZE_INO ||
1509                 (ino >= EXT4_FIRST_INO(sb) &&
1510                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1511 }
1512 
1513 /*
1514  * Inode dynamic state flags
1515  */
1516 enum {
1517         EXT4_STATE_JDATA,               /* journaled data exists */
1518         EXT4_STATE_NEW,                 /* inode is newly created */
1519         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1520         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1521         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1522         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1523         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1524         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1525         EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1526                                            nolocking */
1527         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1528         EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
1529         EXT4_STATE_LUSTRE_EA_INODE,     /* Lustre-style ea_inode */
1530 };
1531 
1532 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1533 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1534 {                                                                       \
1535         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1536 }                                                                       \
1537 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1538 {                                                                       \
1539         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1540 }                                                                       \
1541 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1542 {                                                                       \
1543         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1544 }
1545 
1546 /* Add these declarations here only so that these functions can be
1547  * found by name.  Otherwise, they are very hard to locate. */
1548 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1549 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1550 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1551 EXT4_INODE_BIT_FNS(flag, flags, 0)
1552 
1553 /* Add these declarations here only so that these functions can be
1554  * found by name.  Otherwise, they are very hard to locate. */
1555 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1556 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1557 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1558 #if (BITS_PER_LONG < 64)
1559 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1560 
1561 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1562 {
1563         (ei)->i_state_flags = 0;
1564 }
1565 #else
1566 EXT4_INODE_BIT_FNS(state, flags, 32)
1567 
1568 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1569 {
1570         /* We depend on the fact that callers will set i_flags */
1571 }
1572 #endif
1573 #else
1574 /* Assume that user mode programs are passing in an ext4fs superblock, not
1575  * a kernel struct super_block.  This will allow us to call the feature-test
1576  * macros from user land. */
1577 #define EXT4_SB(sb)     (sb)
1578 #endif
1579 
1580 /*
1581  * Returns true if the inode is inode is encrypted
1582  */
1583 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1584 
1585 /*
1586  * Codes for operating systems
1587  */
1588 #define EXT4_OS_LINUX           0
1589 #define EXT4_OS_HURD            1
1590 #define EXT4_OS_MASIX           2
1591 #define EXT4_OS_FREEBSD         3
1592 #define EXT4_OS_LITES           4
1593 
1594 /*
1595  * Revision levels
1596  */
1597 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1598 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1599 
1600 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1601 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1602 
1603 #define EXT4_GOOD_OLD_INODE_SIZE 128
1604 
1605 /*
1606  * Feature set definitions
1607  */
1608 
1609 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1610 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1611 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1612 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1613 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1614 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1615 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2       0x0200
1616 
1617 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1618 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1619 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1620 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1621 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1622 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1623 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1624 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1625 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1626 /*
1627  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1628  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1629  * all other data structures' checksums.  However, the METADATA_CSUM and
1630  * GDT_CSUM bits are mutually exclusive.
1631  */
1632 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1633 #define EXT4_FEATURE_RO_COMPAT_READONLY         0x1000
1634 #define EXT4_FEATURE_RO_COMPAT_PROJECT          0x2000
1635 
1636 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1637 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1638 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1639 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1640 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1641 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1642 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1643 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1644 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1645 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1646 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1647 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED         0x2000
1648 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1649 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1650 #define EXT4_FEATURE_INCOMPAT_ENCRYPT           0x10000
1651 
1652 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1653 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1654 { \
1655         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1656                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1657 } \
1658 static inline void ext4_set_feature_##name(struct super_block *sb) \
1659 { \
1660         EXT4_SB(sb)->s_es->s_feature_compat |= \
1661                 cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1662 } \
1663 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1664 { \
1665         EXT4_SB(sb)->s_es->s_feature_compat &= \
1666                 ~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1667 }
1668 
1669 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1670 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1671 { \
1672         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1673                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1674 } \
1675 static inline void ext4_set_feature_##name(struct super_block *sb) \
1676 { \
1677         EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1678                 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1679 } \
1680 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1681 { \
1682         EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1683                 ~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1684 }
1685 
1686 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1687 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1688 { \
1689         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1690                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1691 } \
1692 static inline void ext4_set_feature_##name(struct super_block *sb) \
1693 { \
1694         EXT4_SB(sb)->s_es->s_feature_incompat |= \
1695                 cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1696 } \
1697 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1698 { \
1699         EXT4_SB(sb)->s_es->s_feature_incompat &= \
1700                 ~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1701 }
1702 
1703 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,         DIR_PREALLOC)
1704 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,        IMAGIC_INODES)
1705 EXT4_FEATURE_COMPAT_FUNCS(journal,              HAS_JOURNAL)
1706 EXT4_FEATURE_COMPAT_FUNCS(xattr,                EXT_ATTR)
1707 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,         RESIZE_INODE)
1708 EXT4_FEATURE_COMPAT_FUNCS(dir_index,            DIR_INDEX)
1709 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,        SPARSE_SUPER2)
1710 
1711 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,      SPARSE_SUPER)
1712 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,        LARGE_FILE)
1713 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,         BTREE_DIR)
1714 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,         HUGE_FILE)
1715 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,          GDT_CSUM)
1716 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,         DIR_NLINK)
1717 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,       EXTRA_ISIZE)
1718 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,             QUOTA)
1719 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,          BIGALLOC)
1720 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,     METADATA_CSUM)
1721 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,          READONLY)
1722 EXT4_FEATURE_RO_COMPAT_FUNCS(project,           PROJECT)
1723 
1724 EXT4_FEATURE_INCOMPAT_FUNCS(compression,        COMPRESSION)
1725 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,           FILETYPE)
1726 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,     RECOVER)
1727 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,        JOURNAL_DEV)
1728 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,            META_BG)
1729 EXT4_FEATURE_INCOMPAT_FUNCS(extents,            EXTENTS)
1730 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,              64BIT)
1731 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,                MMP)
1732 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,            FLEX_BG)
1733 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,           EA_INODE)
1734 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,            DIRDATA)
1735 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,          CSUM_SEED)
1736 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,           LARGEDIR)
1737 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,        INLINE_DATA)
1738 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,            ENCRYPT)
1739 
1740 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1741 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1742                                          EXT4_FEATURE_INCOMPAT_META_BG)
1743 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1744                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1745                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1746 
1747 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1748 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1749                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1750                                          EXT4_FEATURE_INCOMPAT_META_BG)
1751 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1752                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1753                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1754 
1755 #define EXT4_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1756 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1757                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1758                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1759                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1760                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1761                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1762                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
1763                                          EXT4_FEATURE_INCOMPAT_MMP | \
1764                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1765                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1766                                          EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1767                                          EXT4_FEATURE_INCOMPAT_LARGEDIR)
1768 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1769                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1770                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1771                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1772                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1773                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1774                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1775                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1776                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1777                                          EXT4_FEATURE_RO_COMPAT_QUOTA |\
1778                                          EXT4_FEATURE_RO_COMPAT_PROJECT)
1779 
1780 #define EXTN_FEATURE_FUNCS(ver) \
1781 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1782 { \
1783         return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1784                 cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1785 } \
1786 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1787 { \
1788         return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1789                 cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1790 } \
1791 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1792 { \
1793         return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1794                 cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1795 }
1796 
1797 EXTN_FEATURE_FUNCS(2)
1798 EXTN_FEATURE_FUNCS(3)
1799 EXTN_FEATURE_FUNCS(4)
1800 
1801 static inline bool ext4_has_compat_features(struct super_block *sb)
1802 {
1803         return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1804 }
1805 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1806 {
1807         return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1808 }
1809 static inline bool ext4_has_incompat_features(struct super_block *sb)
1810 {
1811         return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1812 }
1813 
1814 /*
1815  * Superblock flags
1816  */
1817 #define EXT4_FLAGS_RESIZING     0
1818 #define EXT4_FLAGS_SHUTDOWN     1
1819 
1820 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1821 {
1822         return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1823 }
1824 
1825 
1826 /*
1827  * Default values for user and/or group using reserved blocks
1828  */
1829 #define EXT4_DEF_RESUID         0
1830 #define EXT4_DEF_RESGID         0
1831 
1832 /*
1833  * Default project ID
1834  */
1835 #define EXT4_DEF_PROJID         0
1836 
1837 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1838 
1839 /*
1840  * Default mount options
1841  */
1842 #define EXT4_DEFM_DEBUG         0x0001
1843 #define EXT4_DEFM_BSDGROUPS     0x0002
1844 #define EXT4_DEFM_XATTR_USER    0x0004
1845 #define EXT4_DEFM_ACL           0x0008
1846 #define EXT4_DEFM_UID16         0x0010
1847 #define EXT4_DEFM_JMODE         0x0060
1848 #define EXT4_DEFM_JMODE_DATA    0x0020
1849 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1850 #define EXT4_DEFM_JMODE_WBACK   0x0060
1851 #define EXT4_DEFM_NOBARRIER     0x0100
1852 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1853 #define EXT4_DEFM_DISCARD       0x0400
1854 #define EXT4_DEFM_NODELALLOC    0x0800
1855 
1856 /*
1857  * Default journal batch times
1858  */
1859 #define EXT4_DEF_MIN_BATCH_TIME 0
1860 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1861 
1862 /*
1863  * Minimum number of groups in a flexgroup before we separate out
1864  * directories into the first block group of a flexgroup
1865  */
1866 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1867 
1868 /*
1869  * Structure of a directory entry
1870  */
1871 #define EXT4_NAME_LEN 255
1872 
1873 struct ext4_dir_entry {
1874         __le32  inode;                  /* Inode number */
1875         __le16  rec_len;                /* Directory entry length */
1876         __le16  name_len;               /* Name length */
1877         char    name[EXT4_NAME_LEN];    /* File name */
1878 };
1879 
1880 /*
1881  * The new version of the directory entry.  Since EXT4 structures are
1882  * stored in intel byte order, and the name_len field could never be
1883  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1884  * file_type field.
1885  */
1886 struct ext4_dir_entry_2 {
1887         __le32  inode;                  /* Inode number */
1888         __le16  rec_len;                /* Directory entry length */
1889         __u8    name_len;               /* Name length */
1890         __u8    file_type;
1891         char    name[EXT4_NAME_LEN];    /* File name */
1892 };
1893 
1894 /*
1895  * This is a bogus directory entry at the end of each leaf block that
1896  * records checksums.
1897  */
1898 struct ext4_dir_entry_tail {
1899         __le32  det_reserved_zero1;     /* Pretend to be unused */
1900         __le16  det_rec_len;            /* 12 */
1901         __u8    det_reserved_zero2;     /* Zero name length */
1902         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1903         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1904 };
1905 
1906 #define EXT4_DIRENT_TAIL(block, blocksize) \
1907         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1908                                         ((blocksize) - \
1909                                          sizeof(struct ext4_dir_entry_tail))))
1910 
1911 /*
1912  * Ext4 directory file types.  Only the low 3 bits are used.  The
1913  * other bits are reserved for now.
1914  */
1915 #define EXT4_FT_UNKNOWN         0
1916 #define EXT4_FT_REG_FILE        1
1917 #define EXT4_FT_DIR             2
1918 #define EXT4_FT_CHRDEV          3
1919 #define EXT4_FT_BLKDEV          4
1920 #define EXT4_FT_FIFO            5
1921 #define EXT4_FT_SOCK            6
1922 #define EXT4_FT_SYMLINK         7
1923 
1924 #define EXT4_FT_MAX             8
1925 
1926 #define EXT4_FT_DIR_CSUM        0xDE
1927 
1928 /*
1929  * EXT4_DIR_PAD defines the directory entries boundaries
1930  *
1931  * NOTE: It must be a multiple of 4
1932  */
1933 #define EXT4_DIR_PAD                    4
1934 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1935 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1936                                          ~EXT4_DIR_ROUND)
1937 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1938 
1939 /*
1940  * If we ever get support for fs block sizes > page_size, we'll need
1941  * to remove the #if statements in the next two functions...
1942  */
1943 static inline unsigned int
1944 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1945 {
1946         unsigned len = le16_to_cpu(dlen);
1947 
1948 #if (PAGE_SIZE >= 65536)
1949         if (len == EXT4_MAX_REC_LEN || len == 0)
1950                 return blocksize;
1951         return (len & 65532) | ((len & 3) << 16);
1952 #else
1953         return len;
1954 #endif
1955 }
1956 
1957 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1958 {
1959         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1960                 BUG();
1961 #if (PAGE_SIZE >= 65536)
1962         if (len < 65536)
1963                 return cpu_to_le16(len);
1964         if (len == blocksize) {
1965                 if (blocksize == 65536)
1966                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1967                 else
1968                         return cpu_to_le16(0);
1969         }
1970         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1971 #else
1972         return cpu_to_le16(len);
1973 #endif
1974 }
1975 
1976 /*
1977  * Hash Tree Directory indexing
1978  * (c) Daniel Phillips, 2001
1979  */
1980 
1981 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
1982                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1983 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
1984                     !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
1985 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1986 
1987 /* Legal values for the dx_root hash_version field: */
1988 
1989 #define DX_HASH_LEGACY          0
1990 #define DX_HASH_HALF_MD4        1
1991 #define DX_HASH_TEA             2
1992 #define DX_HASH_LEGACY_UNSIGNED 3
1993 #define DX_HASH_HALF_MD4_UNSIGNED       4
1994 #define DX_HASH_TEA_UNSIGNED            5
1995 
1996 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1997                               const void *address, unsigned int length)
1998 {
1999         struct {
2000                 struct shash_desc shash;
2001                 char ctx[4];
2002         } desc;
2003         int err;
2004 
2005         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2006 
2007         desc.shash.tfm = sbi->s_chksum_driver;
2008         desc.shash.flags = 0;
2009         *(u32 *)desc.ctx = crc;
2010 
2011         err = crypto_shash_update(&desc.shash, address, length);
2012         BUG_ON(err);
2013 
2014         return *(u32 *)desc.ctx;
2015 }
2016 
2017 #ifdef __KERNEL__
2018 
2019 /* hash info structure used by the directory hash */
2020 struct dx_hash_info
2021 {
2022         u32             hash;
2023         u32             minor_hash;
2024         int             hash_version;
2025         u32             *seed;
2026 };
2027 
2028 
2029 /* 32 and 64 bit signed EOF for dx directories */
2030 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2031 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2032 
2033 
2034 /*
2035  * Control parameters used by ext4_htree_next_block
2036  */
2037 #define HASH_NB_ALWAYS          1
2038 
2039 struct ext4_filename {
2040         const struct qstr *usr_fname;
2041         struct fscrypt_str disk_name;
2042         struct dx_hash_info hinfo;
2043 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2044         struct fscrypt_str crypto_buf;
2045 #endif
2046 };
2047 
2048 #define fname_name(p) ((p)->disk_name.name)
2049 #define fname_len(p)  ((p)->disk_name.len)
2050 
2051 /*
2052  * Describe an inode's exact location on disk and in memory
2053  */
2054 struct ext4_iloc
2055 {
2056         struct buffer_head *bh;
2057         unsigned long offset;
2058         ext4_group_t block_group;
2059 };
2060 
2061 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2062 {
2063         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2064 }
2065 
2066 static inline bool ext4_is_quota_file(struct inode *inode)
2067 {
2068         return IS_NOQUOTA(inode) &&
2069                !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2070 }
2071 
2072 /*
2073  * This structure is stuffed into the struct file's private_data field
2074  * for directories.  It is where we put information so that we can do
2075  * readdir operations in hash tree order.
2076  */
2077 struct dir_private_info {
2078         struct rb_root  root;
2079         struct rb_node  *curr_node;
2080         struct fname    *extra_fname;
2081         loff_t          last_pos;
2082         __u32           curr_hash;
2083         __u32           curr_minor_hash;
2084         __u32           next_hash;
2085 };
2086 
2087 /* calculate the first block number of the group */
2088 static inline ext4_fsblk_t
2089 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2090 {
2091         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2092                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2093 }
2094 
2095 /*
2096  * Special error return code only used by dx_probe() and its callers.
2097  */
2098 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
2099 
2100 /* htree levels for ext4 */
2101 #define EXT4_HTREE_LEVEL_COMPAT 2
2102 #define EXT4_HTREE_LEVEL        3
2103 
2104 static inline int ext4_dir_htree_level(struct super_block *sb)
2105 {
2106         return ext4_has_feature_largedir(sb) ?
2107                 EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2108 }
2109 
2110 /*
2111  * Timeout and state flag for lazy initialization inode thread.
2112  */
2113 #define EXT4_DEF_LI_WAIT_MULT                   10
2114 #define EXT4_DEF_LI_MAX_START_DELAY             5
2115 #define EXT4_LAZYINIT_QUIT                      0x0001
2116 #define EXT4_LAZYINIT_RUNNING                   0x0002
2117 
2118 /*
2119  * Lazy inode table initialization info
2120  */
2121 struct ext4_lazy_init {
2122         unsigned long           li_state;
2123         struct list_head        li_request_list;
2124         struct mutex            li_list_mtx;
2125 };
2126 
2127 struct ext4_li_request {
2128         struct super_block      *lr_super;
2129         struct ext4_sb_info     *lr_sbi;
2130         ext4_group_t            lr_next_group;
2131         struct list_head        lr_request;
2132         unsigned long           lr_next_sched;
2133         unsigned long           lr_timeout;
2134 };
2135 
2136 struct ext4_features {
2137         struct kobject f_kobj;
2138         struct completion f_kobj_unregister;
2139 };
2140 
2141 /*
2142  * This structure will be used for multiple mount protection. It will be
2143  * written into the block number saved in the s_mmp_block field in the
2144  * superblock. Programs that check MMP should assume that if
2145  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2146  * to use the filesystem, regardless of how old the timestamp is.
2147  */
2148 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2149 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2150 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2151 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2152 
2153 struct mmp_struct {
2154         __le32  mmp_magic;              /* Magic number for MMP */
2155         __le32  mmp_seq;                /* Sequence no. updated periodically */
2156 
2157         /*
2158          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2159          * purposes and do not affect the correctness of the algorithm
2160          */
2161         __le64  mmp_time;               /* Time last updated */
2162         char    mmp_nodename[64];       /* Node which last updated MMP block */
2163         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
2164 
2165         /*
2166          * mmp_check_interval is used to verify if the MMP block has been
2167          * updated on the block device. The value is updated based on the
2168          * maximum time to write the MMP block during an update cycle.
2169          */
2170         __le16  mmp_check_interval;
2171 
2172         __le16  mmp_pad1;
2173         __le32  mmp_pad2[226];
2174         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
2175 };
2176 
2177 /* arguments passed to the mmp thread */
2178 struct mmpd_data {
2179         struct buffer_head *bh; /* bh from initial read_mmp_block() */
2180         struct super_block *sb;  /* super block of the fs */
2181 };
2182 
2183 /*
2184  * Check interval multiplier
2185  * The MMP block is written every update interval and initially checked every
2186  * update interval x the multiplier (the value is then adapted based on the
2187  * write latency). The reason is that writes can be delayed under load and we
2188  * don't want readers to incorrectly assume that the filesystem is no longer
2189  * in use.
2190  */
2191 #define EXT4_MMP_CHECK_MULT             2UL
2192 
2193 /*
2194  * Minimum interval for MMP checking in seconds.
2195  */
2196 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
2197 
2198 /*
2199  * Maximum interval for MMP checking in seconds.
2200  */
2201 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
2202 
2203 /*
2204  * Function prototypes
2205  */
2206 
2207 /*
2208  * Ok, these declarations are also in <linux/kernel.h> but none of the
2209  * ext4 source programs needs to include it so they are duplicated here.
2210  */
2211 # define NORET_TYPE     /**/
2212 # define ATTRIB_NORET   __attribute__((noreturn))
2213 # define NORET_AND      noreturn,
2214 
2215 /* bitmap.c */
2216 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2217 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2218                                 struct ext4_group_desc *gdp,
2219                                 struct buffer_head *bh, int sz);
2220 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2221                                   struct ext4_group_desc *gdp,
2222                                   struct buffer_head *bh, int sz);
2223 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2224                                 struct ext4_group_desc *gdp,
2225                                 struct buffer_head *bh);
2226 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2227                                   struct ext4_group_desc *gdp,
2228                                   struct buffer_head *bh);
2229 
2230 /* balloc.c */
2231 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2232                                          ext4_fsblk_t blocknr,
2233                                          ext4_group_t *blockgrpp,
2234                                          ext4_grpblk_t *offsetp);
2235 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2236                                           ext4_fsblk_t block);
2237 
2238 extern unsigned int ext4_block_group(struct super_block *sb,
2239                         ext4_fsblk_t blocknr);
2240 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2241                         ext4_fsblk_t blocknr);
2242 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2243 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2244                         ext4_group_t group);
2245 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2246                                          ext4_fsblk_t goal,
2247                                          unsigned int flags,
2248                                          unsigned long *count,
2249                                          int *errp);
2250 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2251                                     s64 nclusters, unsigned int flags);
2252 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2253 extern void ext4_check_blocks_bitmap(struct super_block *);
2254 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2255                                                     ext4_group_t block_group,
2256                                                     struct buffer_head ** bh);
2257 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2258 
2259 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2260                                                 ext4_group_t block_group);
2261 extern int ext4_wait_block_bitmap(struct super_block *sb,
2262                                   ext4_group_t block_group,
2263                                   struct buffer_head *bh);
2264 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2265                                                   ext4_group_t block_group);
2266 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2267                                               ext4_group_t block_group,
2268                                               struct ext4_group_desc *gdp);
2269 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2270 
2271 static inline bool ext4_encrypted_inode(struct inode *inode)
2272 {
2273         return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2274 }
2275 
2276 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2277 static inline int ext4_fname_setup_filename(struct inode *dir,
2278                         const struct qstr *iname,
2279                         int lookup, struct ext4_filename *fname)
2280 {
2281         struct fscrypt_name name;
2282         int err;
2283 
2284         memset(fname, 0, sizeof(struct ext4_filename));
2285 
2286         err = fscrypt_setup_filename(dir, iname, lookup, &name);
2287 
2288         fname->usr_fname = name.usr_fname;
2289         fname->disk_name = name.disk_name;
2290         fname->hinfo.hash = name.hash;
2291         fname->hinfo.minor_hash = name.minor_hash;
2292         fname->crypto_buf = name.crypto_buf;
2293         return err;
2294 }
2295 
2296 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2297 {
2298         struct fscrypt_name name;
2299 
2300         name.crypto_buf = fname->crypto_buf;
2301         fscrypt_free_filename(&name);
2302 
2303         fname->crypto_buf.name = NULL;
2304         fname->usr_fname = NULL;
2305         fname->disk_name.name = NULL;
2306 }
2307 #else
2308 static inline int ext4_fname_setup_filename(struct inode *dir,
2309                 const struct qstr *iname,
2310                 int lookup, struct ext4_filename *fname)
2311 {
2312         fname->usr_fname = iname;
2313         fname->disk_name.name = (unsigned char *) iname->name;
2314         fname->disk_name.len = iname->len;
2315         return 0;
2316 }
2317 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2318 
2319 #endif
2320 
2321 /* dir.c */
2322 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2323                                   struct file *,
2324                                   struct ext4_dir_entry_2 *,
2325                                   struct buffer_head *, char *, int,
2326                                   unsigned int);
2327 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)      \
2328         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2329                                         (de), (bh), (buf), (size), (offset)))
2330 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2331                                 __u32 minor_hash,
2332                                 struct ext4_dir_entry_2 *dirent,
2333                                 struct fscrypt_str *ent_name);
2334 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2335 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2336                              struct buffer_head *bh,
2337                              void *buf, int buf_size,
2338                              struct ext4_filename *fname,
2339                              struct ext4_dir_entry_2 **dest_de);
2340 void ext4_insert_dentry(struct inode *inode,
2341                         struct ext4_dir_entry_2 *de,
2342                         int buf_size,
2343                         struct ext4_filename *fname);
2344 static inline void ext4_update_dx_flag(struct inode *inode)
2345 {
2346         if (!ext4_has_feature_dir_index(inode->i_sb))
2347                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2348 }
2349 static const unsigned char ext4_filetype_table[] = {
2350         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2351 };
2352 
2353 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2354 {
2355         if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2356                 return DT_UNKNOWN;
2357 
2358         return ext4_filetype_table[filetype];
2359 }
2360 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2361                              void *buf, int buf_size);
2362 
2363 /* fsync.c */
2364 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2365 
2366 /* hash.c */
2367 extern int ext4fs_dirhash(const char *name, int len, struct
2368                           dx_hash_info *hinfo);
2369 
2370 /* ialloc.c */
2371 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2372                                       const struct qstr *qstr, __u32 goal,
2373                                       uid_t *owner, __u32 i_flags,
2374                                       int handle_type, unsigned int line_no,
2375                                       int nblocks);
2376 
2377 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2378         __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2379                          i_flags, 0, 0, 0)
2380 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2381                                     type, nblocks)                  \
2382         __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2383                          0, (type), __LINE__, (nblocks))
2384 
2385 
2386 extern void ext4_free_inode(handle_t *, struct inode *);
2387 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2388 extern unsigned long ext4_count_free_inodes(struct super_block *);
2389 extern unsigned long ext4_count_dirs(struct super_block *);
2390 extern void ext4_check_inodes_bitmap(struct super_block *);
2391 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2392 extern int ext4_init_inode_table(struct super_block *sb,
2393                                  ext4_group_t group, int barrier);
2394 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2395 
2396 /* mballoc.c */
2397 extern const struct file_operations ext4_seq_mb_groups_fops;
2398 extern long ext4_mb_stats;
2399 extern long ext4_mb_max_to_scan;
2400 extern int ext4_mb_init(struct super_block *);
2401 extern int ext4_mb_release(struct super_block *);
2402 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2403                                 struct ext4_allocation_request *, int *);
2404 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2405 extern void ext4_discard_preallocations(struct inode *);
2406 extern int __init ext4_init_mballoc(void);
2407 extern void ext4_exit_mballoc(void);
2408 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2409                              struct buffer_head *bh, ext4_fsblk_t block,
2410                              unsigned long count, int flags);
2411 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2412                                    ext4_group_t ngroups);
2413 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2414                 ext4_group_t i, struct ext4_group_desc *desc);
2415 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2416                                 ext4_fsblk_t block, unsigned long count);
2417 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2418 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2419 
2420 /* inode.c */
2421 int ext4_inode_is_fast_symlink(struct inode *inode);
2422 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2423 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2424 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2425                      bool wait, struct buffer_head **bhs);
2426 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2427                              struct buffer_head *bh_result, int create);
2428 int ext4_get_block(struct inode *inode, sector_t iblock,
2429                    struct buffer_head *bh_result, int create);
2430 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2431                        struct buffer_head *bh_result, int create);
2432 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2433                            struct buffer_head *bh, int create);
2434 int ext4_walk_page_buffers(handle_t *handle,
2435                            struct buffer_head *head,
2436                            unsigned from,
2437                            unsigned to,
2438                            int *partial,
2439                            int (*fn)(handle_t *handle,
2440                                      struct buffer_head *bh));
2441 int do_journal_get_write_access(handle_t *handle,
2442                                 struct buffer_head *bh);
2443 #define FALL_BACK_TO_NONDELALLOC 1
2444 #define CONVERT_INLINE_DATA      2
2445 
2446 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2447 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2448 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2449 extern int  ext4_setattr(struct dentry *, struct iattr *);
2450 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2451 extern void ext4_evict_inode(struct inode *);
2452 extern void ext4_clear_inode(struct inode *);
2453 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2454 extern int  ext4_sync_inode(handle_t *, struct inode *);
2455 extern void ext4_dirty_inode(struct inode *, int);
2456 extern int ext4_change_inode_journal_flag(struct inode *, int);
2457 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2458 extern int ext4_inode_attach_jinode(struct inode *inode);
2459 extern int ext4_can_truncate(struct inode *inode);
2460 extern int ext4_truncate(struct inode *);
2461 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2462 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2463 extern void ext4_set_inode_flags(struct inode *);
2464 extern int ext4_alloc_da_blocks(struct inode *inode);
2465 extern void ext4_set_aops(struct inode *inode);
2466 extern int ext4_writepage_trans_blocks(struct inode *);
2467 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2468 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2469                              loff_t lstart, loff_t lend);
2470 extern int ext4_page_mkwrite(struct vm_fault *vmf);
2471 extern int ext4_filemap_fault(struct vm_fault *vmf);
2472 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2473 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2474 extern void ext4_da_update_reserve_space(struct inode *inode,
2475                                         int used, int quota_claim);
2476 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2477                               ext4_fsblk_t pblk, ext4_lblk_t len);
2478 
2479 /* indirect.c */
2480 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2481                                 struct ext4_map_blocks *map, int flags);
2482 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2483 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2484 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2485 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2486                                  ext4_lblk_t start, ext4_lblk_t end);
2487 
2488 /* ioctl.c */
2489 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2490 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2491 
2492 /* migrate.c */
2493 extern int ext4_ext_migrate(struct inode *);
2494 extern int ext4_ind_migrate(struct inode *inode);
2495 
2496 /* namei.c */
2497 extern int ext4_dirent_csum_verify(struct inode *inode,
2498                                    struct ext4_dir_entry *dirent);
2499 extern int ext4_orphan_add(handle_t *, struct inode *);
2500 extern int ext4_orphan_del(handle_t *, struct inode *);
2501 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2502                                 __u32 start_minor_hash, __u32 *next_hash);
2503 extern int ext4_search_dir(struct buffer_head *bh,
2504                            char *search_buf,
2505                            int buf_size,
2506                            struct inode *dir,
2507                            struct ext4_filename *fname,
2508                            unsigned int offset,
2509                            struct ext4_dir_entry_2 **res_dir);
2510 extern int ext4_generic_delete_entry(handle_t *handle,
2511                                      struct inode *dir,
2512                                      struct ext4_dir_entry_2 *de_del,
2513                                      struct buffer_head *bh,
2514                                      void *entry_buf,
2515                                      int buf_size,
2516                                      int csum_size);
2517 extern bool ext4_empty_dir(struct inode *inode);
2518 
2519 /* resize.c */
2520 extern int ext4_group_add(struct super_block *sb,
2521                                 struct ext4_new_group_data *input);
2522 extern int ext4_group_extend(struct super_block *sb,
2523                                 struct ext4_super_block *es,
2524                                 ext4_fsblk_t n_blocks_count);
2525 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2526 
2527 /* super.c */
2528 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2529 extern int ext4_calculate_overhead(struct super_block *sb);
2530 extern void ext4_superblock_csum_set(struct super_block *sb);
2531 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2532 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2533 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2534                                     ext4_group_t ngroup);
2535 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2536                                      char nbuf[16]);
2537 
2538 extern __printf(4, 5)
2539 void __ext4_error(struct super_block *, const char *, unsigned int,
2540                   const char *, ...);
2541 extern __printf(5, 6)
2542 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2543                       const char *, ...);
2544 extern __printf(5, 6)
2545 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2546                      const char *, ...);
2547 extern void __ext4_std_error(struct super_block *, const char *,
2548                              unsigned int, int);
2549 extern __printf(4, 5)
2550 void __ext4_abort(struct super_block *, const char *, unsigned int,
2551                   const char *, ...);
2552 extern __printf(4, 5)
2553 void __ext4_warning(struct super_block *, const char *, unsigned int,
2554                     const char *, ...);
2555 extern __printf(4, 5)
2556 void __ext4_warning_inode(const struct inode *inode, const char *function,
2557                           unsigned int line, const char *fmt, ...);
2558 extern __printf(3, 4)
2559 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2560 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2561                            const char *, unsigned int, const char *);
2562 extern __printf(7, 8)
2563 void __ext4_grp_locked_error(const char *, unsigned int,
2564                              struct super_block *, ext4_group_t,
2565                              unsigned long, ext4_fsblk_t,
2566                              const char *, ...);
2567 
2568 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2569         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2570 
2571 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
2572         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2573 
2574 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
2575         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2576 
2577 #ifdef CONFIG_PRINTK
2578 
2579 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
2580         __ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2581 #define ext4_error_file(file, func, line, block, fmt, ...)              \
2582         __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2583 #define ext4_error(sb, fmt, ...)                                        \
2584         __ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2585 #define ext4_abort(sb, fmt, ...)                                        \
2586         __ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2587 #define ext4_warning(sb, fmt, ...)                                      \
2588         __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2589 #define ext4_warning_inode(inode, fmt, ...)                             \
2590         __ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2591 #define ext4_msg(sb, level, fmt, ...)                           \
2592         __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2593 #define dump_mmp_msg(sb, mmp, msg)                                      \
2594         __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2595 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
2596         __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2597                                 fmt, ##__VA_ARGS__)
2598 
2599 #else
2600 
2601 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
2602 do {                                                                    \
2603         no_printk(fmt, ##__VA_ARGS__);                                  \
2604         __ext4_error_inode(inode, "", 0, block, " ");                   \
2605 } while (0)
2606 #define ext4_error_file(file, func, line, block, fmt, ...)              \
2607 do {                                                                    \
2608         no_printk(fmt, ##__VA_ARGS__);                                  \
2609         __ext4_error_file(file, "", 0, block, " ");                     \
2610 } while (0)
2611 #define ext4_error(sb, fmt, ...)                                        \
2612 do {                                                                    \
2613         no_printk(fmt, ##__VA_ARGS__);                                  \
2614         __ext4_error(sb, "", 0, " ");                                   \
2615 } while (0)
2616 #define ext4_abort(sb, fmt, ...)                                        \
2617 do {                                                                    \
2618         no_printk(fmt, ##__VA_ARGS__);                                  \
2619         __ext4_abort(sb, "", 0, " ");                                   \
2620 } while (0)
2621 #define ext4_warning(sb, fmt, ...)                                      \
2622 do {                                                                    \
2623         no_printk(fmt, ##__VA_ARGS__);                                  \
2624         __ext4_warning(sb, "", 0, " ");                                 \
2625 } while (0)
2626 #define ext4_warning_inode(inode, fmt, ...)                             \
2627 do {                                                                    \
2628         no_printk(fmt, ##__VA_ARGS__);                                  \
2629         __ext4_warning_inode(inode, "", 0, " ");                        \
2630 } while (0)
2631 #define ext4_msg(sb, level, fmt, ...)                                   \
2632 do {                                                                    \
2633         no_printk(fmt, ##__VA_ARGS__);                                  \
2634         __ext4_msg(sb, "", " ");                                        \
2635 } while (0)
2636 #define dump_mmp_msg(sb, mmp, msg)                                      \
2637         __dump_mmp_msg(sb, mmp, "", 0, "")
2638 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
2639 do {                                                                    \
2640         no_printk(fmt, ##__VA_ARGS__);                          \
2641         __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");       \
2642 } while (0)
2643 
2644 #endif
2645 
2646 extern void ext4_update_dynamic_rev(struct super_block *sb);
2647 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2648                                         __u32 compat);
2649 extern int ext4_update_rocompat_feature(handle_t *handle,
2650                                         struct super_block *sb, __u32 rocompat);
2651 extern int ext4_update_incompat_feature(handle_t *handle,
2652                                         struct super_block *sb, __u32 incompat);
2653 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2654                                       struct ext4_group_desc *bg);
2655 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2656                                       struct ext4_group_desc *bg);
2657 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2658                                      struct ext4_group_desc *bg);
2659 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2660                                       struct ext4_group_desc *bg);
2661 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2662                                  struct ext4_group_desc *bg);
2663 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2664                                 struct ext4_group_desc *bg);
2665 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2666                                    struct ext4_group_desc *bg);
2667 extern void ext4_block_bitmap_set(struct super_block *sb,
2668                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2669 extern void ext4_inode_bitmap_set(struct super_block *sb,
2670                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2671 extern void ext4_inode_table_set(struct super_block *sb,
2672                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2673 extern void ext4_free_group_clusters_set(struct super_block *sb,
2674                                          struct ext4_group_desc *bg,
2675                                          __u32 count);
2676 extern void ext4_free_inodes_set(struct super_block *sb,
2677                                 struct ext4_group_desc *bg, __u32 count);
2678 extern void ext4_used_dirs_set(struct super_block *sb,
2679                                 struct ext4_group_desc *bg, __u32 count);
2680 extern void ext4_itable_unused_set(struct super_block *sb,
2681                                    struct ext4_group_desc *bg, __u32 count);
2682 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2683                                        struct ext4_group_desc *gdp);
2684 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2685                                      struct ext4_group_desc *gdp);
2686 extern int ext4_register_li_request(struct super_block *sb,
2687                                     ext4_group_t first_not_zeroed);
2688 
2689 static inline int ext4_has_metadata_csum(struct super_block *sb)
2690 {
2691         WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2692                      !EXT4_SB(sb)->s_chksum_driver);
2693 
2694         return ext4_has_feature_metadata_csum(sb) &&
2695                (EXT4_SB(sb)->s_chksum_driver != NULL);
2696 }
2697 
2698 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2699 {
2700         return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2701 }
2702 
2703 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2704 {
2705         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2706                 le32_to_cpu(es->s_blocks_count_lo);
2707 }
2708 
2709 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2710 {
2711         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2712                 le32_to_cpu(es->s_r_blocks_count_lo);
2713 }
2714 
2715 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2716 {
2717         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2718                 le32_to_cpu(es->s_free_blocks_count_lo);
2719 }
2720 
2721 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2722                                          ext4_fsblk_t blk)
2723 {
2724         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2725         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2726 }
2727 
2728 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2729                                               ext4_fsblk_t blk)
2730 {
2731         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2732         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2733 }
2734 
2735 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2736                                            ext4_fsblk_t blk)
2737 {
2738         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2739         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2740 }
2741 
2742 static inline loff_t ext4_isize(struct super_block *sb,
2743                                 struct ext4_inode *raw_inode)
2744 {
2745         if (ext4_has_feature_largedir(sb) ||
2746             S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2747                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2748                         le32_to_cpu(raw_inode->i_size_lo);
2749 
2750         return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2751 }
2752 
2753 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2754 {
2755         raw_inode->i_size_lo = cpu_to_le32(i_size);
2756         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2757 }
2758 
2759 static inline
2760 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2761                                             ext4_group_t group)
2762 {
2763          struct ext4_group_info ***grp_info;
2764          long indexv, indexh;
2765          BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2766          grp_info = EXT4_SB(sb)->s_group_info;
2767          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2768          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2769          return grp_info[indexv][indexh];
2770 }
2771 
2772 /*
2773  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2774  * the locking protocol documented in the comments of ext4_group_add()
2775  * in resize.c
2776  */
2777 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2778 {
2779         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2780 
2781         smp_rmb();
2782         return ngroups;
2783 }
2784 
2785 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2786                                              ext4_group_t block_group)
2787 {
2788         return block_group >> sbi->s_log_groups_per_flex;
2789 }
2790 
2791 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2792 {
2793         return 1 << sbi->s_log_groups_per_flex;
2794 }
2795 
2796 #define ext4_std_error(sb, errno)                               \
2797 do {                                                            \
2798         if ((errno))                                            \
2799                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2800 } while (0)
2801 
2802 #ifdef CONFIG_SMP
2803 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2804  * counters. So we need to make sure we have free clusters more
2805  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2806  */
2807 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2808 #else
2809 #define EXT4_FREECLUSTERS_WATERMARK 0
2810 #endif
2811 
2812 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2813 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2814 {
2815         WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2816                      !inode_is_locked(inode));
2817         down_write(&EXT4_I(inode)->i_data_sem);
2818         if (newsize > EXT4_I(inode)->i_disksize)
2819                 EXT4_I(inode)->i_disksize = newsize;
2820         up_write(&EXT4_I(inode)->i_data_sem);
2821 }
2822 
2823 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2824 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2825 {
2826         int changed = 0;
2827 
2828         if (newsize > inode->i_size) {
2829                 i_size_write(inode, newsize);
2830                 changed = 1;
2831         }
2832         if (newsize > EXT4_I(inode)->i_disksize) {
2833                 ext4_update_i_disksize(inode, newsize);
2834                 changed |= 2;
2835         }
2836         return changed;
2837 }
2838 
2839 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2840                                       loff_t len);
2841 
2842 struct ext4_group_info {
2843         unsigned long   bb_state;
2844         struct rb_root  bb_free_root;
2845         ext4_grpblk_t   bb_first_free;  /* first free block */
2846         ext4_grpblk_t   bb_free;        /* total free blocks */
2847         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2848         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2849         struct          list_head bb_prealloc_list;
2850 #ifdef DOUBLE_CHECK
2851         void            *bb_bitmap;
2852 #endif
2853         struct rw_semaphore alloc_sem;
2854         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2855                                          * regions, index is order.
2856                                          * bb_counters[3] = 5 means
2857                                          * 5 free 8-block regions. */
2858 };
2859 
2860 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2861 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2862 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT     2
2863 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT     3
2864 
2865 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2866         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2867 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)        \
2868         (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2869 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)        \
2870         (test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2871 
2872 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2873         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2874 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2875         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2876 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2877         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2878 
2879 #define EXT4_MAX_CONTENTION             8
2880 #define EXT4_CONTENTION_THRESHOLD       2
2881 
2882 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2883                                               ext4_group_t group)
2884 {
2885         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2886 }
2887 
2888 /*
2889  * Returns true if the filesystem is busy enough that attempts to
2890  * access the block group locks has run into contention.
2891  */
2892 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2893 {
2894         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2895 }
2896 
2897 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2898 {
2899         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2900         if (spin_trylock(lock))
2901                 /*
2902                  * We're able to grab the lock right away, so drop the
2903                  * lock contention counter.
2904                  */
2905                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2906         else {
2907                 /*
2908                  * The lock is busy, so bump the contention counter,
2909                  * and then wait on the spin lock.
2910                  */
2911                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2912                                   EXT4_MAX_CONTENTION);
2913                 spin_lock(lock);
2914         }
2915 }
2916 
2917 static inline void ext4_unlock_group(struct super_block *sb,
2918                                         ext4_group_t group)
2919 {
2920         spin_unlock(ext4_group_lock_ptr(sb, group));
2921 }
2922 
2923 /*
2924  * Block validity checking
2925  */
2926 #define ext4_check_indirect_blockref(inode, bh)                         \
2927         ext4_check_blockref(__func__, __LINE__, inode,                  \
2928                             (__le32 *)(bh)->b_data,                     \
2929                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2930 
2931 #define ext4_ind_check_inode(inode)                                     \
2932         ext4_check_blockref(__func__, __LINE__, inode,                  \
2933                             EXT4_I(inode)->i_data,                      \
2934                             EXT4_NDIR_BLOCKS)
2935 
2936 /*
2937  * Inodes and files operations
2938  */
2939 
2940 /* dir.c */
2941 extern const struct file_operations ext4_dir_operations;
2942 
2943 /* file.c */
2944 extern const struct inode_operations ext4_file_inode_operations;
2945 extern const struct file_operations ext4_file_operations;
2946 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2947 
2948 /* inline.c */
2949 extern int ext4_get_max_inline_size(struct inode *inode);
2950 extern int ext4_find_inline_data_nolock(struct inode *inode);
2951 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2952                                  unsigned int len);
2953 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2954 
2955 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2956 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2957                                          struct inode *inode,
2958                                          loff_t pos, unsigned len,
2959                                          unsigned flags,
2960                                          struct page **pagep);
2961 extern int ext4_write_inline_data_end(struct inode *inode,
2962                                       loff_t pos, unsigned len,
2963                                       unsigned copied,
2964                                       struct page *page);
2965 extern struct buffer_head *
2966 ext4_journalled_write_inline_data(struct inode *inode,
2967                                   unsigned len,
2968                                   struct page *page);
2969 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2970                                            struct inode *inode,
2971                                            loff_t pos, unsigned len,
2972                                            unsigned flags,
2973                                            struct page **pagep,
2974                                            void **fsdata);
2975 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2976                                          unsigned len, unsigned copied,
2977                                          struct page *page);
2978 extern int ext4_try_add_inline_entry(handle_t *handle,
2979                                      struct ext4_filename *fname,
2980                                      struct inode *dir, struct inode *inode);
2981 extern int ext4_try_create_inline_dir(handle_t *handle,
2982                                       struct inode *parent,
2983                                       struct inode *inode);
2984 extern int ext4_read_inline_dir(struct file *filp,
2985                                 struct dir_context *ctx,
2986                                 int *has_inline_data);
2987 extern int htree_inlinedir_to_tree(struct file *dir_file,
2988                                    struct inode *dir, ext4_lblk_t block,
2989                                    struct dx_hash_info *hinfo,
2990                                    __u32 start_hash, __u32 start_minor_hash,
2991                                    int *has_inline_data);
2992 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2993                                         struct ext4_filename *fname,
2994                                         struct ext4_dir_entry_2 **res_dir,
2995                                         int *has_inline_data);
2996 extern int ext4_delete_inline_entry(handle_t *handle,
2997                                     struct inode *dir,
2998                                     struct ext4_dir_entry_2 *de_del,
2999                                     struct buffer_head *bh,
3000                                     int *has_inline_data);
3001 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3002 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3003                                         struct ext4_dir_entry_2 **parent_de,
3004                                         int *retval);
3005 extern int ext4_inline_data_fiemap(struct inode *inode,
3006                                    struct fiemap_extent_info *fieinfo,
3007                                    int *has_inline, __u64 start, __u64 len);
3008 
3009 struct iomap;
3010 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3011 
3012 extern int ext4_try_to_evict_inline_data(handle_t *handle,
3013                                          struct inode *inode,
3014                                          int needed);
3015 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3016 
3017 extern int ext4_convert_inline_data(struct inode *inode);
3018 
3019 static inline int ext4_has_inline_data(struct inode *inode)
3020 {
3021         return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3022                EXT4_I(inode)->i_inline_off;
3023 }
3024 
3025 /* namei.c */
3026 extern const struct inode_operations ext4_dir_inode_operations;
3027 extern const struct inode_operations ext4_special_inode_operations;
3028 extern struct dentry *ext4_get_parent(struct dentry *child);
3029 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3030                                  struct ext4_dir_entry_2 *de,
3031                                  int blocksize, int csum_size,
3032                                  unsigned int parent_ino, int dotdot_real_len);
3033 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3034                                    unsigned int blocksize);
3035 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3036                                          struct inode *inode,
3037                                          struct buffer_head *bh);
3038 #define S_SHIFT 12
3039 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3040         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
3041         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
3042         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
3043         [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
3044         [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
3045         [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
3046         [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
3047 };
3048 
3049 static inline void ext4_set_de_type(struct super_block *sb,
3050                                 struct ext4_dir_entry_2 *de,
3051                                 umode_t mode) {
3052         if (ext4_has_feature_filetype(sb))
3053                 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3054 }
3055 
3056 /* readpages.c */
3057 extern int ext4_mpage_readpages(struct address_space *mapping,
3058                                 struct list_head *pages, struct page *page,
3059                                 unsigned nr_pages);
3060 
3061 /* symlink.c */
3062 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3063 extern const struct inode_operations ext4_symlink_inode_operations;
3064 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3065 
3066 /* sysfs.c */
3067 extern int ext4_register_sysfs(struct super_block *sb);
3068 extern void ext4_unregister_sysfs(struct super_block *sb);
3069 extern int __init ext4_init_sysfs(void);
3070 extern void ext4_exit_sysfs(void);
3071 
3072 /* block_validity */
3073 extern void ext4_release_system_zone(struct super_block *sb);
3074 extern int ext4_setup_system_zone(struct super_block *sb);
3075 extern int __init ext4_init_system_zone(void);
3076 extern void ext4_exit_system_zone(void);
3077 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3078                                  ext4_fsblk_t start_blk,
3079                                  unsigned int count);
3080 extern int ext4_check_blockref(const char *, unsigned int,
3081                                struct inode *, __le32 *, unsigned int);
3082 
3083 /* extents.c */
3084 struct ext4_ext_path;
3085 struct ext4_extent;
3086 
3087 /*
3088  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3089  * __le32.
3090  */
3091 #define EXT_MAX_BLOCKS  0xffffffff
3092 
3093 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3094 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3095 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3096 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3097                                struct ext4_map_blocks *map, int flags);
3098 extern int ext4_ext_truncate(handle_t *, struct inode *);
3099 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3100                                  ext4_lblk_t end);
3101 extern void ext4_ext_init(struct super_block *);
3102 extern void ext4_ext_release(struct super_block *);
3103 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3104                           loff_t len);
3105 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3106                                           loff_t offset, ssize_t len);
3107 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3108                            struct ext4_map_blocks *map, int flags);
3109 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3110                                          ext4_lblk_t lblocks);
3111 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3112                                                    int num,
3113                                                    struct ext4_ext_path *path);
3114 extern int ext4_can_extents_be_merged(struct inode *inode,
3115                                       struct ext4_extent *ex1,
3116                                       struct ext4_extent *ex2);
3117 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3118                                   struct ext4_ext_path **,
3119                                   struct ext4_extent *, int);
3120 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3121                                               struct ext4_ext_path **,
3122                                               int flags);
3123 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3124 extern int ext4_ext_check_inode(struct inode *inode);
3125 extern int ext4_find_delalloc_range(struct inode *inode,
3126                                     ext4_lblk_t lblk_start,
3127                                     ext4_lblk_t lblk_end);
3128 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3129 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3130 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3131                         __u64 start, __u64 len);
3132 extern int ext4_ext_precache(struct inode *inode);
3133 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3134 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3135 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3136                                 struct inode *inode2, ext4_lblk_t lblk1,
3137                              ext4_lblk_t lblk2,  ext4_lblk_t count,
3138                              int mark_unwritten,int *err);
3139 
3140 /* move_extent.c */
3141 extern void ext4_double_down_write_data_sem(struct inode *first,
3142                                             struct inode *second);
3143 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3144                                           struct inode *donor_inode);
3145 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3146                              __u64 start_orig, __u64 start_donor,
3147                              __u64 len, __u64 *moved_len);
3148 
3149 /* page-io.c */
3150 extern int __init ext4_init_pageio(void);
3151 extern void ext4_exit_pageio(void);
3152 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3153 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3154 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3155 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3156 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3157                                 struct writeback_control *wbc);
3158 extern void ext4_end_io_rsv_work(struct work_struct *work);
3159 extern void ext4_io_submit(struct ext4_io_submit *io);
3160 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3161                                struct page *page,
3162                                int len,
3163                                struct writeback_control *wbc,
3164                                bool keep_towrite);
3165 
3166 /* mmp.c */
3167 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3168 
3169 /*
3170  * Add new method to test whether block and inode bitmaps are properly
3171  * initialized. With uninit_bg reading the block from disk is not enough
3172  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3173  */
3174 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3175 
3176 static inline int bitmap_uptodate(struct buffer_head *bh)
3177 {
3178         return (buffer_uptodate(bh) &&
3179                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3180 }
3181 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3182 {
3183         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3184 }
3185 
3186 /*
3187  * Disable DIO read nolock optimization, so new dioreaders will be forced
3188  * to grab i_mutex
3189  */
3190 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3191 {
3192         ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3193         smp_mb();
3194 }
3195 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3196 {
3197         smp_mb();
3198         ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3199 }
3200 
3201 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
3202 
3203 /* For ioend & aio unwritten conversion wait queues */
3204 #define EXT4_WQ_HASH_SZ         37
3205 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3206                                             EXT4_WQ_HASH_SZ])
3207 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3208 
3209 extern int ext4_resize_begin(struct super_block *sb);
3210 extern void ext4_resize_end(struct super_block *sb);
3211 
3212 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3213                                               struct ext4_io_end *io_end)
3214 {
3215         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3216                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
3217                 atomic_inc(&EXT4_I(inode)->i_unwritten);
3218         }
3219 }
3220 
3221 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3222 {
3223         struct inode *inode = io_end->inode;
3224 
3225         if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3226                 io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3227                 /* Wake up anyone waiting on unwritten extent conversion */
3228                 if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3229                         wake_up_all(ext4_ioend_wq(inode));
3230         }
3231 }
3232 
3233 extern const struct iomap_ops ext4_iomap_ops;
3234 
3235 #endif  /* __KERNEL__ */
3236 
3237 #define EFSBADCRC       EBADMSG         /* Bad CRC detected */
3238 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
3239 
3240 #endif  /* _EXT4_H */
3241 

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