Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[firefly-linux-kernel-4.4.55.git] / fs / ext4 / ext4.h
1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15
16 #ifndef _EXT4_H
17 #define _EXT4_H
18
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/wait.h>
30 #include <linux/blockgroup_lock.h>
31 #include <linux/percpu_counter.h>
32 #ifdef __KERNEL__
33 #include <linux/compat.h>
34 #endif
35
36 /*
37  * The fourth extended filesystem constants/structures
38  */
39
40 /*
41  * Define EXT4FS_DEBUG to produce debug messages
42  */
43 #undef EXT4FS_DEBUG
44
45 /*
46  * Debug code
47  */
48 #ifdef EXT4FS_DEBUG
49 #define ext4_debug(f, a...)                                             \
50         do {                                                            \
51                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
52                         __FILE__, __LINE__, __func__);                  \
53                 printk(KERN_DEBUG f, ## a);                             \
54         } while (0)
55 #else
56 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
57 #endif
58
59 #define EXT4_ERROR_INODE(inode, fmt, a...) \
60         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
61
62 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
63         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
64
65 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
66         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
67
68 /* data type for block offset of block group */
69 typedef int ext4_grpblk_t;
70
71 /* data type for filesystem-wide blocks number */
72 typedef unsigned long long ext4_fsblk_t;
73
74 /* data type for file logical block number */
75 typedef __u32 ext4_lblk_t;
76
77 /* data type for block group number */
78 typedef unsigned int ext4_group_t;
79
80 /*
81  * Flags used in mballoc's allocation_context flags field.
82  *
83  * Also used to show what's going on for debugging purposes when the
84  * flag field is exported via the traceport interface
85  */
86
87 /* prefer goal again. length */
88 #define EXT4_MB_HINT_MERGE              0x0001
89 /* blocks already reserved */
90 #define EXT4_MB_HINT_RESERVED           0x0002
91 /* metadata is being allocated */
92 #define EXT4_MB_HINT_METADATA           0x0004
93 /* first blocks in the file */
94 #define EXT4_MB_HINT_FIRST              0x0008
95 /* search for the best chunk */
96 #define EXT4_MB_HINT_BEST               0x0010
97 /* data is being allocated */
98 #define EXT4_MB_HINT_DATA               0x0020
99 /* don't preallocate (for tails) */
100 #define EXT4_MB_HINT_NOPREALLOC         0x0040
101 /* allocate for locality group */
102 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
103 /* allocate goal blocks or none */
104 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
105 /* goal is meaningful */
106 #define EXT4_MB_HINT_TRY_GOAL           0x0200
107 /* blocks already pre-reserved by delayed allocation */
108 #define EXT4_MB_DELALLOC_RESERVED       0x0400
109 /* We are doing stream allocation */
110 #define EXT4_MB_STREAM_ALLOC            0x0800
111 /* Use reserved root blocks if needed */
112 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
113
114 struct ext4_allocation_request {
115         /* target inode for block we're allocating */
116         struct inode *inode;
117         /* how many blocks we want to allocate */
118         unsigned int len;
119         /* logical block in target inode */
120         ext4_lblk_t logical;
121         /* the closest logical allocated block to the left */
122         ext4_lblk_t lleft;
123         /* the closest logical allocated block to the right */
124         ext4_lblk_t lright;
125         /* phys. target (a hint) */
126         ext4_fsblk_t goal;
127         /* phys. block for the closest logical allocated block to the left */
128         ext4_fsblk_t pleft;
129         /* phys. block for the closest logical allocated block to the right */
130         ext4_fsblk_t pright;
131         /* flags. see above EXT4_MB_HINT_* */
132         unsigned int flags;
133 };
134
135 /*
136  * Logical to physical block mapping, used by ext4_map_blocks()
137  *
138  * This structure is used to pass requests into ext4_map_blocks() as
139  * well as to store the information returned by ext4_map_blocks().  It
140  * takes less room on the stack than a struct buffer_head.
141  */
142 #define EXT4_MAP_NEW            (1 << BH_New)
143 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
144 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
145 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
146 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
147 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
148  * ext4_map_blocks wants to know whether or not the underlying cluster has
149  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
150  * the requested mapping was from previously mapped (or delayed allocated)
151  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
152  * should never appear on buffer_head's state flags.
153  */
154 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
155 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
156                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
157                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
158
159 struct ext4_map_blocks {
160         ext4_fsblk_t m_pblk;
161         ext4_lblk_t m_lblk;
162         unsigned int m_len;
163         unsigned int m_flags;
164 };
165
166 /*
167  * For delayed allocation tracking
168  */
169 struct mpage_da_data {
170         struct inode *inode;
171         sector_t b_blocknr;             /* start block number of extent */
172         size_t b_size;                  /* size of extent */
173         unsigned long b_state;          /* state of the extent */
174         unsigned long first_page, next_page;    /* extent of pages */
175         struct writeback_control *wbc;
176         int io_done;
177         int pages_written;
178         int retval;
179 };
180
181 /*
182  * Flags for ext4_io_end->flags
183  */
184 #define EXT4_IO_END_UNWRITTEN   0x0001
185 #define EXT4_IO_END_ERROR       0x0002
186 #define EXT4_IO_END_QUEUED      0x0004
187 #define EXT4_IO_END_DIRECT      0x0008
188 #define EXT4_IO_END_IN_FSYNC    0x0010
189
190 struct ext4_io_page {
191         struct page     *p_page;
192         atomic_t        p_count;
193 };
194
195 #define MAX_IO_PAGES 128
196
197 /*
198  * For converting uninitialized extents on a work queue.
199  *
200  * 'page' is only used from the writepage() path; 'pages' is only used for
201  * buffered writes; they are used to keep page references until conversion
202  * takes place.  For AIO/DIO, neither field is filled in.
203  */
204 typedef struct ext4_io_end {
205         struct list_head        list;           /* per-file finished IO list */
206         struct inode            *inode;         /* file being written to */
207         unsigned int            flag;           /* unwritten or not */
208         struct page             *page;          /* for writepage() path */
209         loff_t                  offset;         /* offset in the file */
210         ssize_t                 size;           /* size of the extent */
211         struct work_struct      work;           /* data work queue */
212         struct kiocb            *iocb;          /* iocb struct for AIO */
213         int                     result;         /* error value for AIO */
214         int                     num_io_pages;   /* for writepages() */
215         struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
216 } ext4_io_end_t;
217
218 struct ext4_io_submit {
219         int                     io_op;
220         struct bio              *io_bio;
221         ext4_io_end_t           *io_end;
222         struct ext4_io_page     *io_page;
223         sector_t                io_next_block;
224 };
225
226 /*
227  * Special inodes numbers
228  */
229 #define EXT4_BAD_INO             1      /* Bad blocks inode */
230 #define EXT4_ROOT_INO            2      /* Root inode */
231 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
232 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
233 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
234 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
235 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
236 #define EXT4_JOURNAL_INO         8      /* Journal inode */
237
238 /* First non-reserved inode for old ext4 filesystems */
239 #define EXT4_GOOD_OLD_FIRST_INO 11
240
241 /*
242  * Maximal count of links to a file
243  */
244 #define EXT4_LINK_MAX           65000
245
246 /*
247  * Macro-instructions used to manage several block sizes
248  */
249 #define EXT4_MIN_BLOCK_SIZE             1024
250 #define EXT4_MAX_BLOCK_SIZE             65536
251 #define EXT4_MIN_BLOCK_LOG_SIZE         10
252 #define EXT4_MAX_BLOCK_LOG_SIZE         16
253 #ifdef __KERNEL__
254 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
255 #else
256 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
257 #endif
258 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
259 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
260                                          EXT4_SB(s)->s_cluster_bits)
261 #ifdef __KERNEL__
262 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
263 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
264 #else
265 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
266 #endif
267 #ifdef __KERNEL__
268 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
269 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
270 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
271 #else
272 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
273                                  EXT4_GOOD_OLD_INODE_SIZE : \
274                                  (s)->s_inode_size)
275 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
276                                  EXT4_GOOD_OLD_FIRST_INO : \
277                                  (s)->s_first_ino)
278 #endif
279 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
280
281 /* Translate a block number to a cluster number */
282 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
283 /* Translate a cluster number to a block number */
284 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
285 /* Translate # of blks to # of clusters */
286 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
287                                  (sbi)->s_cluster_bits)
288
289 /*
290  * Structure of a blocks group descriptor
291  */
292 struct ext4_group_desc
293 {
294         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
295         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
296         __le32  bg_inode_table_lo;      /* Inodes table block */
297         __le16  bg_free_blocks_count_lo;/* Free blocks count */
298         __le16  bg_free_inodes_count_lo;/* Free inodes count */
299         __le16  bg_used_dirs_count_lo;  /* Directories count */
300         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
301         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
302         __le16  bg_itable_unused_lo;    /* Unused inodes count */
303         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
304         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
305         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
306         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
307         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
308         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
309         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
310         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
311         __u32   bg_reserved2[3];
312 };
313
314 /*
315  * Structure of a flex block group info
316  */
317
318 struct flex_groups {
319         atomic_t free_inodes;
320         atomic_t free_clusters;
321         atomic_t used_dirs;
322 };
323
324 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
325 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
326 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
327
328 /*
329  * Macro-instructions used to manage group descriptors
330  */
331 #define EXT4_MIN_DESC_SIZE              32
332 #define EXT4_MIN_DESC_SIZE_64BIT        64
333 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
334 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
335 #ifdef __KERNEL__
336 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
337 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
338 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
339 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
340 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
341 #else
342 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
343 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
344 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
345 #endif
346
347 /*
348  * Constants relative to the data blocks
349  */
350 #define EXT4_NDIR_BLOCKS                12
351 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
352 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
353 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
354 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
355
356 /*
357  * Inode flags
358  */
359 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
360 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
361 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
362 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
363 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
364 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
365 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
366 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
367 /* Reserved for compression usage... */
368 #define EXT4_DIRTY_FL                   0x00000100
369 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
370 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
371 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
372 /* End compression flags --- maybe not all used */
373 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
374 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
375 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
376 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
377 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
378 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
379 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
380 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
381 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
382 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
383 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
384
385 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
386 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
387
388 /* Flags that should be inherited by new inodes from their parent. */
389 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
390                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
391                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
392                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
393
394 /* Flags that are appropriate for regular files (all but dir-specific ones). */
395 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
396
397 /* Flags that are appropriate for non-directories/regular files. */
398 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
399
400 /* Mask out flags that are inappropriate for the given type of inode. */
401 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
402 {
403         if (S_ISDIR(mode))
404                 return flags;
405         else if (S_ISREG(mode))
406                 return flags & EXT4_REG_FLMASK;
407         else
408                 return flags & EXT4_OTHER_FLMASK;
409 }
410
411 /*
412  * Inode flags used for atomic set/get
413  */
414 enum {
415         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
416         EXT4_INODE_UNRM         = 1,    /* Undelete */
417         EXT4_INODE_COMPR        = 2,    /* Compress file */
418         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
419         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
420         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
421         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
422         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
423 /* Reserved for compression usage... */
424         EXT4_INODE_DIRTY        = 8,
425         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
426         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
427         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
428 /* End compression flags --- maybe not all used */
429         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
430         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
431         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
432         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
433         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
434         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
435         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
436         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
437         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
438         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
439         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
440 };
441
442 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
443 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
444         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
445                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
446
447 /*
448  * Since it's pretty easy to mix up bit numbers and hex values, and we
449  * can't do a compile-time test for ENUM values, we use a run-time
450  * test to make sure that EXT4_XXX_FL is consistent with respect to
451  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
452  * out so it won't cost any extra space in the compiled kernel image.
453  * But it's important that these values are the same, since we are
454  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
455  * must be consistent with the values of FS_XXX_FL defined in
456  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
457  * ext4 filesystems, and of course the values defined in e2fsprogs.
458  *
459  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
460  */
461 static inline void ext4_check_flag_values(void)
462 {
463         CHECK_FLAG_VALUE(SECRM);
464         CHECK_FLAG_VALUE(UNRM);
465         CHECK_FLAG_VALUE(COMPR);
466         CHECK_FLAG_VALUE(SYNC);
467         CHECK_FLAG_VALUE(IMMUTABLE);
468         CHECK_FLAG_VALUE(APPEND);
469         CHECK_FLAG_VALUE(NODUMP);
470         CHECK_FLAG_VALUE(NOATIME);
471         CHECK_FLAG_VALUE(DIRTY);
472         CHECK_FLAG_VALUE(COMPRBLK);
473         CHECK_FLAG_VALUE(NOCOMPR);
474         CHECK_FLAG_VALUE(ECOMPR);
475         CHECK_FLAG_VALUE(INDEX);
476         CHECK_FLAG_VALUE(IMAGIC);
477         CHECK_FLAG_VALUE(JOURNAL_DATA);
478         CHECK_FLAG_VALUE(NOTAIL);
479         CHECK_FLAG_VALUE(DIRSYNC);
480         CHECK_FLAG_VALUE(TOPDIR);
481         CHECK_FLAG_VALUE(HUGE_FILE);
482         CHECK_FLAG_VALUE(EXTENTS);
483         CHECK_FLAG_VALUE(EA_INODE);
484         CHECK_FLAG_VALUE(EOFBLOCKS);
485         CHECK_FLAG_VALUE(RESERVED);
486 }
487
488 /* Used to pass group descriptor data when online resize is done */
489 struct ext4_new_group_input {
490         __u32 group;            /* Group number for this data */
491         __u64 block_bitmap;     /* Absolute block number of block bitmap */
492         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
493         __u64 inode_table;      /* Absolute block number of inode table start */
494         __u32 blocks_count;     /* Total number of blocks in this group */
495         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
496         __u16 unused;
497 };
498
499 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
500 struct compat_ext4_new_group_input {
501         u32 group;
502         compat_u64 block_bitmap;
503         compat_u64 inode_bitmap;
504         compat_u64 inode_table;
505         u32 blocks_count;
506         u16 reserved_blocks;
507         u16 unused;
508 };
509 #endif
510
511 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
512 struct ext4_new_group_data {
513         __u32 group;
514         __u64 block_bitmap;
515         __u64 inode_bitmap;
516         __u64 inode_table;
517         __u32 blocks_count;
518         __u16 reserved_blocks;
519         __u16 unused;
520         __u32 free_blocks_count;
521 };
522
523 /* Indexes used to index group tables in ext4_new_group_data */
524 enum {
525         BLOCK_BITMAP = 0,       /* block bitmap */
526         INODE_BITMAP,           /* inode bitmap */
527         INODE_TABLE,            /* inode tables */
528         GROUP_TABLE_COUNT,
529 };
530
531 /*
532  * Flags used by ext4_map_blocks()
533  */
534         /* Allocate any needed blocks and/or convert an unitialized
535            extent to be an initialized ext4 */
536 #define EXT4_GET_BLOCKS_CREATE                  0x0001
537         /* Request the creation of an unitialized extent */
538 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
539 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
540                                                  EXT4_GET_BLOCKS_CREATE)
541         /* Caller is from the delayed allocation writeout path,
542            so set the magic i_delalloc_reserve_flag after taking the
543            inode allocation semaphore for */
544 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
545         /* caller is from the direct IO path, request to creation of an
546         unitialized extents if not allocated, split the uninitialized
547         extent if blocks has been preallocated already*/
548 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
549 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
550 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
551                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
552         /* Convert extent to initialized after IO complete */
553 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
554                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
555         /* Punch out blocks of an extent */
556 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
557         /* Don't normalize allocation size (used for fallocate) */
558 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
559         /* Request will not result in inode size update (user for fallocate) */
560 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
561
562 /*
563  * Flags used by ext4_free_blocks
564  */
565 #define EXT4_FREE_BLOCKS_METADATA       0x0001
566 #define EXT4_FREE_BLOCKS_FORGET         0x0002
567 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
568 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
569 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
570 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
571
572 /*
573  * Flags used by ext4_discard_partial_page_buffers
574  */
575 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
576
577 /*
578  * ioctl commands
579  */
580 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
581 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
582 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
583 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
584 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
585 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
586 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
587 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
588 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
589 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
590 #define EXT4_IOC_MIGRATE                _IO('f', 9)
591  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
592  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
593 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
594 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
595 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
596
597 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
598 /*
599  * ioctl commands in 32 bit emulation
600  */
601 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
602 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
603 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
604 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
605 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
606 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
607 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
608 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
609 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
610 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
611 #endif
612
613 /* Max physical block we can address w/o extents */
614 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
615
616 /*
617  * Structure of an inode on the disk
618  */
619 struct ext4_inode {
620         __le16  i_mode;         /* File mode */
621         __le16  i_uid;          /* Low 16 bits of Owner Uid */
622         __le32  i_size_lo;      /* Size in bytes */
623         __le32  i_atime;        /* Access time */
624         __le32  i_ctime;        /* Inode Change time */
625         __le32  i_mtime;        /* Modification time */
626         __le32  i_dtime;        /* Deletion Time */
627         __le16  i_gid;          /* Low 16 bits of Group Id */
628         __le16  i_links_count;  /* Links count */
629         __le32  i_blocks_lo;    /* Blocks count */
630         __le32  i_flags;        /* File flags */
631         union {
632                 struct {
633                         __le32  l_i_version;
634                 } linux1;
635                 struct {
636                         __u32  h_i_translator;
637                 } hurd1;
638                 struct {
639                         __u32  m_i_reserved1;
640                 } masix1;
641         } osd1;                         /* OS dependent 1 */
642         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
643         __le32  i_generation;   /* File version (for NFS) */
644         __le32  i_file_acl_lo;  /* File ACL */
645         __le32  i_size_high;
646         __le32  i_obso_faddr;   /* Obsoleted fragment address */
647         union {
648                 struct {
649                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
650                         __le16  l_i_file_acl_high;
651                         __le16  l_i_uid_high;   /* these 2 fields */
652                         __le16  l_i_gid_high;   /* were reserved2[0] */
653                         __u32   l_i_reserved2;
654                 } linux2;
655                 struct {
656                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
657                         __u16   h_i_mode_high;
658                         __u16   h_i_uid_high;
659                         __u16   h_i_gid_high;
660                         __u32   h_i_author;
661                 } hurd2;
662                 struct {
663                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
664                         __le16  m_i_file_acl_high;
665                         __u32   m_i_reserved2[2];
666                 } masix2;
667         } osd2;                         /* OS dependent 2 */
668         __le16  i_extra_isize;
669         __le16  i_pad1;
670         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
671         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
672         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
673         __le32  i_crtime;       /* File Creation time */
674         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
675         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
676 };
677
678 struct move_extent {
679         __u32 reserved;         /* should be zero */
680         __u32 donor_fd;         /* donor file descriptor */
681         __u64 orig_start;       /* logical start offset in block for orig */
682         __u64 donor_start;      /* logical start offset in block for donor */
683         __u64 len;              /* block length to be moved */
684         __u64 moved_len;        /* moved block length */
685 };
686
687 #define EXT4_EPOCH_BITS 2
688 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
689 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
690
691 /*
692  * Extended fields will fit into an inode if the filesystem was formatted
693  * with large inodes (-I 256 or larger) and there are not currently any EAs
694  * consuming all of the available space. For new inodes we always reserve
695  * enough space for the kernel's known extended fields, but for inodes
696  * created with an old kernel this might not have been the case. None of
697  * the extended inode fields is critical for correct filesystem operation.
698  * This macro checks if a certain field fits in the inode. Note that
699  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
700  */
701 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
702         ((offsetof(typeof(*ext4_inode), field) +        \
703           sizeof((ext4_inode)->field))                  \
704         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
705             (einode)->i_extra_isize))                   \
706
707 static inline __le32 ext4_encode_extra_time(struct timespec *time)
708 {
709        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
710                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
711                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
712 }
713
714 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
715 {
716        if (sizeof(time->tv_sec) > 4)
717                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
718                                << 32;
719        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
720 }
721
722 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
723 do {                                                                           \
724         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
725         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
726                 (raw_inode)->xtime ## _extra =                                 \
727                                 ext4_encode_extra_time(&(inode)->xtime);       \
728 } while (0)
729
730 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
731 do {                                                                           \
732         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
733                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
734         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
735                 (raw_inode)->xtime ## _extra =                                 \
736                                 ext4_encode_extra_time(&(einode)->xtime);      \
737 } while (0)
738
739 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
740 do {                                                                           \
741         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
742         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
743                 ext4_decode_extra_time(&(inode)->xtime,                        \
744                                        raw_inode->xtime ## _extra);            \
745         else                                                                   \
746                 (inode)->xtime.tv_nsec = 0;                                    \
747 } while (0)
748
749 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
750 do {                                                                           \
751         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
752                 (einode)->xtime.tv_sec =                                       \
753                         (signed)le32_to_cpu((raw_inode)->xtime);               \
754         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
755                 ext4_decode_extra_time(&(einode)->xtime,                       \
756                                        raw_inode->xtime ## _extra);            \
757         else                                                                   \
758                 (einode)->xtime.tv_nsec = 0;                                   \
759 } while (0)
760
761 #define i_disk_version osd1.linux1.l_i_version
762
763 #if defined(__KERNEL__) || defined(__linux__)
764 #define i_reserved1     osd1.linux1.l_i_reserved1
765 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
766 #define i_blocks_high   osd2.linux2.l_i_blocks_high
767 #define i_uid_low       i_uid
768 #define i_gid_low       i_gid
769 #define i_uid_high      osd2.linux2.l_i_uid_high
770 #define i_gid_high      osd2.linux2.l_i_gid_high
771 #define i_reserved2     osd2.linux2.l_i_reserved2
772
773 #elif defined(__GNU__)
774
775 #define i_translator    osd1.hurd1.h_i_translator
776 #define i_uid_high      osd2.hurd2.h_i_uid_high
777 #define i_gid_high      osd2.hurd2.h_i_gid_high
778 #define i_author        osd2.hurd2.h_i_author
779
780 #elif defined(__masix__)
781
782 #define i_reserved1     osd1.masix1.m_i_reserved1
783 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
784 #define i_reserved2     osd2.masix2.m_i_reserved2
785
786 #endif /* defined(__KERNEL__) || defined(__linux__) */
787
788 /*
789  * storage for cached extent
790  * If ec_len == 0, then the cache is invalid.
791  * If ec_start == 0, then the cache represents a gap (null mapping)
792  */
793 struct ext4_ext_cache {
794         ext4_fsblk_t    ec_start;
795         ext4_lblk_t     ec_block;
796         __u32           ec_len; /* must be 32bit to return holes */
797 };
798
799 /*
800  * fourth extended file system inode data in memory
801  */
802 struct ext4_inode_info {
803         __le32  i_data[15];     /* unconverted */
804         __u32   i_dtime;
805         ext4_fsblk_t    i_file_acl;
806
807         /*
808          * i_block_group is the number of the block group which contains
809          * this file's inode.  Constant across the lifetime of the inode,
810          * it is ued for making block allocation decisions - we try to
811          * place a file's data blocks near its inode block, and new inodes
812          * near to their parent directory's inode.
813          */
814         ext4_group_t    i_block_group;
815         ext4_lblk_t     i_dir_start_lookup;
816 #if (BITS_PER_LONG < 64)
817         unsigned long   i_state_flags;          /* Dynamic state flags */
818 #endif
819         unsigned long   i_flags;
820
821 #ifdef CONFIG_EXT4_FS_XATTR
822         /*
823          * Extended attributes can be read independently of the main file
824          * data. Taking i_mutex even when reading would cause contention
825          * between readers of EAs and writers of regular file data, so
826          * instead we synchronize on xattr_sem when reading or changing
827          * EAs.
828          */
829         struct rw_semaphore xattr_sem;
830 #endif
831
832         struct list_head i_orphan;      /* unlinked but open inodes */
833
834         /*
835          * i_disksize keeps track of what the inode size is ON DISK, not
836          * in memory.  During truncate, i_size is set to the new size by
837          * the VFS prior to calling ext4_truncate(), but the filesystem won't
838          * set i_disksize to 0 until the truncate is actually under way.
839          *
840          * The intent is that i_disksize always represents the blocks which
841          * are used by this file.  This allows recovery to restart truncate
842          * on orphans if we crash during truncate.  We actually write i_disksize
843          * into the on-disk inode when writing inodes out, instead of i_size.
844          *
845          * The only time when i_disksize and i_size may be different is when
846          * a truncate is in progress.  The only things which change i_disksize
847          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
848          */
849         loff_t  i_disksize;
850
851         /*
852          * i_data_sem is for serialising ext4_truncate() against
853          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
854          * data tree are chopped off during truncate. We can't do that in
855          * ext4 because whenever we perform intermediate commits during
856          * truncate, the inode and all the metadata blocks *must* be in a
857          * consistent state which allows truncation of the orphans to restart
858          * during recovery.  Hence we must fix the get_block-vs-truncate race
859          * by other means, so we have i_data_sem.
860          */
861         struct rw_semaphore i_data_sem;
862         struct inode vfs_inode;
863         struct jbd2_inode *jinode;
864
865         struct ext4_ext_cache i_cached_extent;
866         /*
867          * File creation time. Its function is same as that of
868          * struct timespec i_{a,c,m}time in the generic inode.
869          */
870         struct timespec i_crtime;
871
872         /* mballoc */
873         struct list_head i_prealloc_list;
874         spinlock_t i_prealloc_lock;
875
876         /* ialloc */
877         ext4_group_t    i_last_alloc_group;
878
879         /* allocation reservation info for delalloc */
880         /* In case of bigalloc, these refer to clusters rather than blocks */
881         unsigned int i_reserved_data_blocks;
882         unsigned int i_reserved_meta_blocks;
883         unsigned int i_allocated_meta_blocks;
884         ext4_lblk_t i_da_metadata_calc_last_lblock;
885         int i_da_metadata_calc_len;
886
887         /* on-disk additional length */
888         __u16 i_extra_isize;
889
890 #ifdef CONFIG_QUOTA
891         /* quota space reservation, managed internally by quota code */
892         qsize_t i_reserved_quota;
893 #endif
894
895         /* completed IOs that might need unwritten extents handling */
896         struct list_head i_completed_io_list;
897         spinlock_t i_completed_io_lock;
898         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
899         /* current io_end structure for async DIO write*/
900         ext4_io_end_t *cur_aio_dio;
901         atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
902
903         spinlock_t i_block_reservation_lock;
904
905         /*
906          * Transactions that contain inode's metadata needed to complete
907          * fsync and fdatasync, respectively.
908          */
909         tid_t i_sync_tid;
910         tid_t i_datasync_tid;
911 };
912
913 /*
914  * File system states
915  */
916 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
917 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
918 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
919
920 /*
921  * Misc. filesystem flags
922  */
923 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
924 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
925 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
926
927 /*
928  * Mount flags
929  */
930 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
931 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
932 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
933 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
934 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
935 #define EXT4_MOUNT_ERRORS_MASK          0x00070
936 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
937 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
938 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
939 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
940 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
941 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
942 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
943 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
944 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
945 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
946 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
947 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
948 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
949 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
950 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
951 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
952 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
953 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
954 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
955 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
956 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
957 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
958 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
959 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
960
961 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
962                                                       specified delalloc */
963
964 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
965                                                 ~EXT4_MOUNT_##opt
966 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
967                                                 EXT4_MOUNT_##opt
968 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
969                                          EXT4_MOUNT_##opt)
970
971 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
972                                                 ~EXT4_MOUNT2_##opt
973 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
974                                                 EXT4_MOUNT2_##opt
975 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
976                                          EXT4_MOUNT2_##opt)
977
978 #define ext4_test_and_set_bit           __test_and_set_bit_le
979 #define ext4_set_bit                    __set_bit_le
980 #define ext4_set_bit_atomic             ext2_set_bit_atomic
981 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
982 #define ext4_clear_bit                  __clear_bit_le
983 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
984 #define ext4_test_bit                   test_bit_le
985 #define ext4_find_next_zero_bit         find_next_zero_bit_le
986 #define ext4_find_next_bit              find_next_bit_le
987
988 extern void ext4_set_bits(void *bm, int cur, int len);
989
990 /*
991  * Maximal mount counts between two filesystem checks
992  */
993 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
994 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
995
996 /*
997  * Behaviour when detecting errors
998  */
999 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1000 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1001 #define EXT4_ERRORS_PANIC               3       /* Panic */
1002 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1003
1004 /*
1005  * Structure of the super block
1006  */
1007 struct ext4_super_block {
1008 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1009         __le32  s_blocks_count_lo;      /* Blocks count */
1010         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1011         __le32  s_free_blocks_count_lo; /* Free blocks count */
1012 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1013         __le32  s_first_data_block;     /* First Data Block */
1014         __le32  s_log_block_size;       /* Block size */
1015         __le32  s_log_cluster_size;     /* Allocation cluster size */
1016 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1017         __le32  s_clusters_per_group;   /* # Clusters per group */
1018         __le32  s_inodes_per_group;     /* # Inodes per group */
1019         __le32  s_mtime;                /* Mount time */
1020 /*30*/  __le32  s_wtime;                /* Write time */
1021         __le16  s_mnt_count;            /* Mount count */
1022         __le16  s_max_mnt_count;        /* Maximal mount count */
1023         __le16  s_magic;                /* Magic signature */
1024         __le16  s_state;                /* File system state */
1025         __le16  s_errors;               /* Behaviour when detecting errors */
1026         __le16  s_minor_rev_level;      /* minor revision level */
1027 /*40*/  __le32  s_lastcheck;            /* time of last check */
1028         __le32  s_checkinterval;        /* max. time between checks */
1029         __le32  s_creator_os;           /* OS */
1030         __le32  s_rev_level;            /* Revision level */
1031 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1032         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1033         /*
1034          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1035          *
1036          * Note: the difference between the compatible feature set and
1037          * the incompatible feature set is that if there is a bit set
1038          * in the incompatible feature set that the kernel doesn't
1039          * know about, it should refuse to mount the filesystem.
1040          *
1041          * e2fsck's requirements are more strict; if it doesn't know
1042          * about a feature in either the compatible or incompatible
1043          * feature set, it must abort and not try to meddle with
1044          * things it doesn't understand...
1045          */
1046         __le32  s_first_ino;            /* First non-reserved inode */
1047         __le16  s_inode_size;           /* size of inode structure */
1048         __le16  s_block_group_nr;       /* block group # of this superblock */
1049         __le32  s_feature_compat;       /* compatible feature set */
1050 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1051         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1052 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1053 /*78*/  char    s_volume_name[16];      /* volume name */
1054 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1055 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1056         /*
1057          * Performance hints.  Directory preallocation should only
1058          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1059          */
1060         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1061         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1062         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1063         /*
1064          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1065          */
1066 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1067 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1068         __le32  s_journal_dev;          /* device number of journal file */
1069         __le32  s_last_orphan;          /* start of list of inodes to delete */
1070         __le32  s_hash_seed[4];         /* HTREE hash seed */
1071         __u8    s_def_hash_version;     /* Default hash version to use */
1072         __u8    s_jnl_backup_type;
1073         __le16  s_desc_size;            /* size of group descriptor */
1074 /*100*/ __le32  s_default_mount_opts;
1075         __le32  s_first_meta_bg;        /* First metablock block group */
1076         __le32  s_mkfs_time;            /* When the filesystem was created */
1077         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1078         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1079 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1080         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1081         __le32  s_free_blocks_count_hi; /* Free blocks count */
1082         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1083         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1084         __le32  s_flags;                /* Miscellaneous flags */
1085         __le16  s_raid_stride;          /* RAID stride */
1086         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1087         __le64  s_mmp_block;            /* Block for multi-mount protection */
1088         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1089         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1090         __u8    s_reserved_char_pad;
1091         __le16  s_reserved_pad;
1092         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1093         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1094         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1095         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1096                                               snapshot's future use */
1097         __le32  s_snapshot_list;        /* inode number of the head of the
1098                                            on-disk snapshot list */
1099 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1100         __le32  s_error_count;          /* number of fs errors */
1101         __le32  s_first_error_time;     /* first time an error happened */
1102         __le32  s_first_error_ino;      /* inode involved in first error */
1103         __le64  s_first_error_block;    /* block involved of first error */
1104         __u8    s_first_error_func[32]; /* function where the error happened */
1105         __le32  s_first_error_line;     /* line number where error happened */
1106         __le32  s_last_error_time;      /* most recent time of an error */
1107         __le32  s_last_error_ino;       /* inode involved in last error */
1108         __le32  s_last_error_line;      /* line number where error happened */
1109         __le64  s_last_error_block;     /* block involved of last error */
1110         __u8    s_last_error_func[32];  /* function where the error happened */
1111 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1112         __u8    s_mount_opts[64];
1113         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1114         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1115         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1116         __le32  s_reserved[109];        /* Padding to the end of the block */
1117 };
1118
1119 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1120
1121 #ifdef __KERNEL__
1122
1123 /*
1124  * run-time mount flags
1125  */
1126 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1127 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1128
1129 /*
1130  * fourth extended-fs super-block data in memory
1131  */
1132 struct ext4_sb_info {
1133         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1134         unsigned long s_inodes_per_block;/* Number of inodes per block */
1135         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1136         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1137         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1138         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1139         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1140         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1141         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1142         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1143         unsigned long s_overhead_last;  /* Last calculated overhead */
1144         unsigned long s_blocks_last;    /* Last seen block count */
1145         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1146         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1147         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1148         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1149         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1150         struct buffer_head **s_group_desc;
1151         unsigned int s_mount_opt;
1152         unsigned int s_mount_opt2;
1153         unsigned int s_mount_flags;
1154         unsigned int s_def_mount_opt;
1155         ext4_fsblk_t s_sb_block;
1156         kuid_t s_resuid;
1157         kgid_t s_resgid;
1158         unsigned short s_mount_state;
1159         unsigned short s_pad;
1160         int s_addr_per_block_bits;
1161         int s_desc_per_block_bits;
1162         int s_inode_size;
1163         int s_first_ino;
1164         unsigned int s_inode_readahead_blks;
1165         unsigned int s_inode_goal;
1166         spinlock_t s_next_gen_lock;
1167         u32 s_next_generation;
1168         u32 s_hash_seed[4];
1169         int s_def_hash_version;
1170         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1171         struct percpu_counter s_freeclusters_counter;
1172         struct percpu_counter s_freeinodes_counter;
1173         struct percpu_counter s_dirs_counter;
1174         struct percpu_counter s_dirtyclusters_counter;
1175         struct blockgroup_lock *s_blockgroup_lock;
1176         struct proc_dir_entry *s_proc;
1177         struct kobject s_kobj;
1178         struct completion s_kobj_unregister;
1179
1180         /* Journaling */
1181         struct journal_s *s_journal;
1182         struct list_head s_orphan;
1183         struct mutex s_orphan_lock;
1184         unsigned long s_resize_flags;           /* Flags indicating if there
1185                                                    is a resizer */
1186         unsigned long s_commit_interval;
1187         u32 s_max_batch_time;
1188         u32 s_min_batch_time;
1189         struct block_device *journal_bdev;
1190 #ifdef CONFIG_QUOTA
1191         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1192         int s_jquota_fmt;                       /* Format of quota to use */
1193 #endif
1194         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1195         struct rb_root system_blks;
1196
1197 #ifdef EXTENTS_STATS
1198         /* ext4 extents stats */
1199         unsigned long s_ext_min;
1200         unsigned long s_ext_max;
1201         unsigned long s_depth_max;
1202         spinlock_t s_ext_stats_lock;
1203         unsigned long s_ext_blocks;
1204         unsigned long s_ext_extents;
1205 #endif
1206
1207         /* for buddy allocator */
1208         struct ext4_group_info ***s_group_info;
1209         struct inode *s_buddy_cache;
1210         spinlock_t s_md_lock;
1211         unsigned short *s_mb_offsets;
1212         unsigned int *s_mb_maxs;
1213
1214         /* tunables */
1215         unsigned long s_stripe;
1216         unsigned int s_mb_stream_request;
1217         unsigned int s_mb_max_to_scan;
1218         unsigned int s_mb_min_to_scan;
1219         unsigned int s_mb_stats;
1220         unsigned int s_mb_order2_reqs;
1221         unsigned int s_mb_group_prealloc;
1222         unsigned int s_max_writeback_mb_bump;
1223         /* where last allocation was done - for stream allocation */
1224         unsigned long s_mb_last_group;
1225         unsigned long s_mb_last_start;
1226
1227         /* stats for buddy allocator */
1228         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1229         atomic_t s_bal_success; /* we found long enough chunks */
1230         atomic_t s_bal_allocated;       /* in blocks */
1231         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1232         atomic_t s_bal_goals;   /* goal hits */
1233         atomic_t s_bal_breaks;  /* too long searches */
1234         atomic_t s_bal_2orders; /* 2^order hits */
1235         spinlock_t s_bal_lock;
1236         unsigned long s_mb_buddies_generated;
1237         unsigned long long s_mb_generation_time;
1238         atomic_t s_mb_lost_chunks;
1239         atomic_t s_mb_preallocated;
1240         atomic_t s_mb_discarded;
1241         atomic_t s_lock_busy;
1242
1243         /* locality groups */
1244         struct ext4_locality_group __percpu *s_locality_groups;
1245
1246         /* for write statistics */
1247         unsigned long s_sectors_written_start;
1248         u64 s_kbytes_written;
1249
1250         unsigned int s_log_groups_per_flex;
1251         struct flex_groups *s_flex_groups;
1252
1253         /* workqueue for dio unwritten */
1254         struct workqueue_struct *dio_unwritten_wq;
1255
1256         /* timer for periodic error stats printing */
1257         struct timer_list s_err_report;
1258
1259         /* Lazy inode table initialization info */
1260         struct ext4_li_request *s_li_request;
1261         /* Wait multiplier for lazy initialization thread */
1262         unsigned int s_li_wait_mult;
1263
1264         /* Kernel thread for multiple mount protection */
1265         struct task_struct *s_mmp_tsk;
1266
1267         /* record the last minlen when FITRIM is called. */
1268         atomic_t s_last_trim_minblks;
1269 };
1270
1271 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1272 {
1273         return sb->s_fs_info;
1274 }
1275 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1276 {
1277         return container_of(inode, struct ext4_inode_info, vfs_inode);
1278 }
1279
1280 static inline struct timespec ext4_current_time(struct inode *inode)
1281 {
1282         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1283                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1284 }
1285
1286 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1287 {
1288         return ino == EXT4_ROOT_INO ||
1289                 ino == EXT4_JOURNAL_INO ||
1290                 ino == EXT4_RESIZE_INO ||
1291                 (ino >= EXT4_FIRST_INO(sb) &&
1292                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1293 }
1294
1295 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1296                                               struct ext4_io_end *io_end)
1297 {
1298         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1299                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1300                 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
1301         }
1302 }
1303
1304 /*
1305  * Inode dynamic state flags
1306  */
1307 enum {
1308         EXT4_STATE_JDATA,               /* journaled data exists */
1309         EXT4_STATE_NEW,                 /* inode is newly created */
1310         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1311         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1312         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1313         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1314         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1315         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1316         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1317 };
1318
1319 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1320 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1321 {                                                                       \
1322         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1323 }                                                                       \
1324 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1325 {                                                                       \
1326         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1327 }                                                                       \
1328 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1329 {                                                                       \
1330         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1331 }
1332
1333 EXT4_INODE_BIT_FNS(flag, flags, 0)
1334 #if (BITS_PER_LONG < 64)
1335 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1336
1337 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1338 {
1339         (ei)->i_state_flags = 0;
1340 }
1341 #else
1342 EXT4_INODE_BIT_FNS(state, flags, 32)
1343
1344 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1345 {
1346         /* We depend on the fact that callers will set i_flags */
1347 }
1348 #endif
1349 #else
1350 /* Assume that user mode programs are passing in an ext4fs superblock, not
1351  * a kernel struct super_block.  This will allow us to call the feature-test
1352  * macros from user land. */
1353 #define EXT4_SB(sb)     (sb)
1354 #endif
1355
1356 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1357
1358 /*
1359  * Codes for operating systems
1360  */
1361 #define EXT4_OS_LINUX           0
1362 #define EXT4_OS_HURD            1
1363 #define EXT4_OS_MASIX           2
1364 #define EXT4_OS_FREEBSD         3
1365 #define EXT4_OS_LITES           4
1366
1367 /*
1368  * Revision levels
1369  */
1370 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1371 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1372
1373 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1374 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1375
1376 #define EXT4_GOOD_OLD_INODE_SIZE 128
1377
1378 /*
1379  * Feature set definitions
1380  */
1381
1382 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1383         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1384 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1385         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1386 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1387         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1388 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1389         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1390 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1391         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1392 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1393         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1394 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1395         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1396 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1397         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1398 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1399         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1400
1401 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1402 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1403 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1404 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1405 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1406 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1407
1408 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1409 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1410 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1411 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1412 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1413 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1414 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1415 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1416 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1417 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1418
1419 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1420 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1421 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1422 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1423 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1424 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1425 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1426 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1427 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1428 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1429 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1430 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1431 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1432 #define EXT4_FEATURE_INCOMPAT_INLINEDATA        0x8000 /* data in inode */
1433
1434 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1435 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1436                                          EXT4_FEATURE_INCOMPAT_META_BG)
1437 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1438                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1439                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1440
1441 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1442 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1443                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1444                                          EXT4_FEATURE_INCOMPAT_META_BG)
1445 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1446                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1447                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1448
1449 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1450 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1451                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1452                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1453                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1454                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1455                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1456                                          EXT4_FEATURE_INCOMPAT_MMP)
1457 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1458                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1459                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1460                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1461                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1462                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1463                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1464                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC)
1465
1466 /*
1467  * Default values for user and/or group using reserved blocks
1468  */
1469 #define EXT4_DEF_RESUID         0
1470 #define EXT4_DEF_RESGID         0
1471
1472 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1473
1474 /*
1475  * Default mount options
1476  */
1477 #define EXT4_DEFM_DEBUG         0x0001
1478 #define EXT4_DEFM_BSDGROUPS     0x0002
1479 #define EXT4_DEFM_XATTR_USER    0x0004
1480 #define EXT4_DEFM_ACL           0x0008
1481 #define EXT4_DEFM_UID16         0x0010
1482 #define EXT4_DEFM_JMODE         0x0060
1483 #define EXT4_DEFM_JMODE_DATA    0x0020
1484 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1485 #define EXT4_DEFM_JMODE_WBACK   0x0060
1486 #define EXT4_DEFM_NOBARRIER     0x0100
1487 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1488 #define EXT4_DEFM_DISCARD       0x0400
1489 #define EXT4_DEFM_NODELALLOC    0x0800
1490
1491 /*
1492  * Default journal batch times
1493  */
1494 #define EXT4_DEF_MIN_BATCH_TIME 0
1495 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1496
1497 /*
1498  * Minimum number of groups in a flexgroup before we separate out
1499  * directories into the first block group of a flexgroup
1500  */
1501 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1502
1503 /*
1504  * Structure of a directory entry
1505  */
1506 #define EXT4_NAME_LEN 255
1507
1508 struct ext4_dir_entry {
1509         __le32  inode;                  /* Inode number */
1510         __le16  rec_len;                /* Directory entry length */
1511         __le16  name_len;               /* Name length */
1512         char    name[EXT4_NAME_LEN];    /* File name */
1513 };
1514
1515 /*
1516  * The new version of the directory entry.  Since EXT4 structures are
1517  * stored in intel byte order, and the name_len field could never be
1518  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1519  * file_type field.
1520  */
1521 struct ext4_dir_entry_2 {
1522         __le32  inode;                  /* Inode number */
1523         __le16  rec_len;                /* Directory entry length */
1524         __u8    name_len;               /* Name length */
1525         __u8    file_type;
1526         char    name[EXT4_NAME_LEN];    /* File name */
1527 };
1528
1529 /*
1530  * Ext4 directory file types.  Only the low 3 bits are used.  The
1531  * other bits are reserved for now.
1532  */
1533 #define EXT4_FT_UNKNOWN         0
1534 #define EXT4_FT_REG_FILE        1
1535 #define EXT4_FT_DIR             2
1536 #define EXT4_FT_CHRDEV          3
1537 #define EXT4_FT_BLKDEV          4
1538 #define EXT4_FT_FIFO            5
1539 #define EXT4_FT_SOCK            6
1540 #define EXT4_FT_SYMLINK         7
1541
1542 #define EXT4_FT_MAX             8
1543
1544 /*
1545  * EXT4_DIR_PAD defines the directory entries boundaries
1546  *
1547  * NOTE: It must be a multiple of 4
1548  */
1549 #define EXT4_DIR_PAD                    4
1550 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1551 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1552                                          ~EXT4_DIR_ROUND)
1553 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1554
1555 /*
1556  * If we ever get support for fs block sizes > page_size, we'll need
1557  * to remove the #if statements in the next two functions...
1558  */
1559 static inline unsigned int
1560 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1561 {
1562         unsigned len = le16_to_cpu(dlen);
1563
1564 #if (PAGE_CACHE_SIZE >= 65536)
1565         if (len == EXT4_MAX_REC_LEN || len == 0)
1566                 return blocksize;
1567         return (len & 65532) | ((len & 3) << 16);
1568 #else
1569         return len;
1570 #endif
1571 }
1572
1573 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1574 {
1575         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1576                 BUG();
1577 #if (PAGE_CACHE_SIZE >= 65536)
1578         if (len < 65536)
1579                 return cpu_to_le16(len);
1580         if (len == blocksize) {
1581                 if (blocksize == 65536)
1582                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1583                 else
1584                         return cpu_to_le16(0);
1585         }
1586         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1587 #else
1588         return cpu_to_le16(len);
1589 #endif
1590 }
1591
1592 /*
1593  * Hash Tree Directory indexing
1594  * (c) Daniel Phillips, 2001
1595  */
1596
1597 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1598                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1599                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1600 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1601 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1602
1603 /* Legal values for the dx_root hash_version field: */
1604
1605 #define DX_HASH_LEGACY          0
1606 #define DX_HASH_HALF_MD4        1
1607 #define DX_HASH_TEA             2
1608 #define DX_HASH_LEGACY_UNSIGNED 3
1609 #define DX_HASH_HALF_MD4_UNSIGNED       4
1610 #define DX_HASH_TEA_UNSIGNED            5
1611
1612 #ifdef __KERNEL__
1613
1614 /* hash info structure used by the directory hash */
1615 struct dx_hash_info
1616 {
1617         u32             hash;
1618         u32             minor_hash;
1619         int             hash_version;
1620         u32             *seed;
1621 };
1622
1623
1624 /* 32 and 64 bit signed EOF for dx directories */
1625 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1626 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1627
1628
1629 /*
1630  * Control parameters used by ext4_htree_next_block
1631  */
1632 #define HASH_NB_ALWAYS          1
1633
1634
1635 /*
1636  * Describe an inode's exact location on disk and in memory
1637  */
1638 struct ext4_iloc
1639 {
1640         struct buffer_head *bh;
1641         unsigned long offset;
1642         ext4_group_t block_group;
1643 };
1644
1645 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1646 {
1647         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1648 }
1649
1650 /*
1651  * This structure is stuffed into the struct file's private_data field
1652  * for directories.  It is where we put information so that we can do
1653  * readdir operations in hash tree order.
1654  */
1655 struct dir_private_info {
1656         struct rb_root  root;
1657         struct rb_node  *curr_node;
1658         struct fname    *extra_fname;
1659         loff_t          last_pos;
1660         __u32           curr_hash;
1661         __u32           curr_minor_hash;
1662         __u32           next_hash;
1663 };
1664
1665 /* calculate the first block number of the group */
1666 static inline ext4_fsblk_t
1667 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1668 {
1669         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1670                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1671 }
1672
1673 /*
1674  * Special error return code only used by dx_probe() and its callers.
1675  */
1676 #define ERR_BAD_DX_DIR  -75000
1677
1678 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1679                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1680
1681 /*
1682  * Timeout and state flag for lazy initialization inode thread.
1683  */
1684 #define EXT4_DEF_LI_WAIT_MULT                   10
1685 #define EXT4_DEF_LI_MAX_START_DELAY             5
1686 #define EXT4_LAZYINIT_QUIT                      0x0001
1687 #define EXT4_LAZYINIT_RUNNING                   0x0002
1688
1689 /*
1690  * Lazy inode table initialization info
1691  */
1692 struct ext4_lazy_init {
1693         unsigned long           li_state;
1694         struct list_head        li_request_list;
1695         struct mutex            li_list_mtx;
1696 };
1697
1698 struct ext4_li_request {
1699         struct super_block      *lr_super;
1700         struct ext4_sb_info     *lr_sbi;
1701         ext4_group_t            lr_next_group;
1702         struct list_head        lr_request;
1703         unsigned long           lr_next_sched;
1704         unsigned long           lr_timeout;
1705 };
1706
1707 struct ext4_features {
1708         struct kobject f_kobj;
1709         struct completion f_kobj_unregister;
1710 };
1711
1712 /*
1713  * This structure will be used for multiple mount protection. It will be
1714  * written into the block number saved in the s_mmp_block field in the
1715  * superblock. Programs that check MMP should assume that if
1716  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1717  * to use the filesystem, regardless of how old the timestamp is.
1718  */
1719 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1720 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1721 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1722 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1723
1724 struct mmp_struct {
1725         __le32  mmp_magic;              /* Magic number for MMP */
1726         __le32  mmp_seq;                /* Sequence no. updated periodically */
1727
1728         /*
1729          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1730          * purposes and do not affect the correctness of the algorithm
1731          */
1732         __le64  mmp_time;               /* Time last updated */
1733         char    mmp_nodename[64];       /* Node which last updated MMP block */
1734         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1735
1736         /*
1737          * mmp_check_interval is used to verify if the MMP block has been
1738          * updated on the block device. The value is updated based on the
1739          * maximum time to write the MMP block during an update cycle.
1740          */
1741         __le16  mmp_check_interval;
1742
1743         __le16  mmp_pad1;
1744         __le32  mmp_pad2[227];
1745 };
1746
1747 /* arguments passed to the mmp thread */
1748 struct mmpd_data {
1749         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1750         struct super_block *sb;  /* super block of the fs */
1751 };
1752
1753 /*
1754  * Check interval multiplier
1755  * The MMP block is written every update interval and initially checked every
1756  * update interval x the multiplier (the value is then adapted based on the
1757  * write latency). The reason is that writes can be delayed under load and we
1758  * don't want readers to incorrectly assume that the filesystem is no longer
1759  * in use.
1760  */
1761 #define EXT4_MMP_CHECK_MULT             2UL
1762
1763 /*
1764  * Minimum interval for MMP checking in seconds.
1765  */
1766 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1767
1768 /*
1769  * Maximum interval for MMP checking in seconds.
1770  */
1771 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1772
1773 /*
1774  * Function prototypes
1775  */
1776
1777 /*
1778  * Ok, these declarations are also in <linux/kernel.h> but none of the
1779  * ext4 source programs needs to include it so they are duplicated here.
1780  */
1781 # define NORET_TYPE     /**/
1782 # define ATTRIB_NORET   __attribute__((noreturn))
1783 # define NORET_AND      noreturn,
1784
1785 /* bitmap.c */
1786 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1787
1788 /* balloc.c */
1789 extern unsigned int ext4_block_group(struct super_block *sb,
1790                         ext4_fsblk_t blocknr);
1791 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1792                         ext4_fsblk_t blocknr);
1793 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1794 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1795                         ext4_group_t group);
1796 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1797                                          ext4_fsblk_t goal,
1798                                          unsigned int flags,
1799                                          unsigned long *count,
1800                                          int *errp);
1801 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1802                                     s64 nclusters, unsigned int flags);
1803 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1804 extern void ext4_check_blocks_bitmap(struct super_block *);
1805 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1806                                                     ext4_group_t block_group,
1807                                                     struct buffer_head ** bh);
1808 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1809
1810 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1811                                                 ext4_group_t block_group);
1812 extern int ext4_wait_block_bitmap(struct super_block *sb,
1813                                   ext4_group_t block_group,
1814                                   struct buffer_head *bh);
1815 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1816                                                   ext4_group_t block_group);
1817 extern void ext4_init_block_bitmap(struct super_block *sb,
1818                                    struct buffer_head *bh,
1819                                    ext4_group_t group,
1820                                    struct ext4_group_desc *desc);
1821 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1822                                               ext4_group_t block_group,
1823                                               struct ext4_group_desc *gdp);
1824 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1825                                            ext4_group_t block_group,
1826                                            struct ext4_group_desc *gdp);
1827 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1828
1829 /* dir.c */
1830 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1831                                   struct file *,
1832                                   struct ext4_dir_entry_2 *,
1833                                   struct buffer_head *, unsigned int);
1834 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1835         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1836                                         (de), (bh), (offset)))
1837 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1838                                     __u32 minor_hash,
1839                                     struct ext4_dir_entry_2 *dirent);
1840 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1841
1842 /* fsync.c */
1843 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1844 extern int ext4_flush_completed_IO(struct inode *);
1845
1846 /* hash.c */
1847 extern int ext4fs_dirhash(const char *name, int len, struct
1848                           dx_hash_info *hinfo);
1849
1850 /* ialloc.c */
1851 extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1852                                     const struct qstr *qstr, __u32 goal,
1853                                     uid_t *owner);
1854 extern void ext4_free_inode(handle_t *, struct inode *);
1855 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1856 extern unsigned long ext4_count_free_inodes(struct super_block *);
1857 extern unsigned long ext4_count_dirs(struct super_block *);
1858 extern void ext4_check_inodes_bitmap(struct super_block *);
1859 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1860 extern int ext4_init_inode_table(struct super_block *sb,
1861                                  ext4_group_t group, int barrier);
1862 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1863
1864 /* mballoc.c */
1865 extern long ext4_mb_stats;
1866 extern long ext4_mb_max_to_scan;
1867 extern int ext4_mb_init(struct super_block *, int);
1868 extern int ext4_mb_release(struct super_block *);
1869 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1870                                 struct ext4_allocation_request *, int *);
1871 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1872 extern void ext4_discard_preallocations(struct inode *);
1873 extern int __init ext4_init_mballoc(void);
1874 extern void ext4_exit_mballoc(void);
1875 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1876                              struct buffer_head *bh, ext4_fsblk_t block,
1877                              unsigned long count, int flags);
1878 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1879                 ext4_group_t i, struct ext4_group_desc *desc);
1880 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1881                                 ext4_fsblk_t block, unsigned long count);
1882 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1883
1884 /* inode.c */
1885 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1886                                                 ext4_lblk_t, int, int *);
1887 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1888                                                 ext4_lblk_t, int, int *);
1889 int ext4_get_block(struct inode *inode, sector_t iblock,
1890                                 struct buffer_head *bh_result, int create);
1891
1892 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1893 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1894 extern int  ext4_setattr(struct dentry *, struct iattr *);
1895 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1896                                 struct kstat *stat);
1897 extern void ext4_evict_inode(struct inode *);
1898 extern void ext4_clear_inode(struct inode *);
1899 extern int  ext4_sync_inode(handle_t *, struct inode *);
1900 extern void ext4_dirty_inode(struct inode *, int);
1901 extern int ext4_change_inode_journal_flag(struct inode *, int);
1902 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1903 extern int ext4_can_truncate(struct inode *inode);
1904 extern void ext4_truncate(struct inode *);
1905 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1906 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1907 extern void ext4_set_inode_flags(struct inode *);
1908 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1909 extern int ext4_alloc_da_blocks(struct inode *inode);
1910 extern void ext4_set_aops(struct inode *inode);
1911 extern int ext4_writepage_trans_blocks(struct inode *);
1912 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1913 extern int ext4_discard_partial_page_buffers(handle_t *handle,
1914                 struct address_space *mapping, loff_t from,
1915                 loff_t length, int flags);
1916 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1917 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1918 extern void ext4_da_update_reserve_space(struct inode *inode,
1919                                         int used, int quota_claim);
1920
1921 /* indirect.c */
1922 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
1923                                 struct ext4_map_blocks *map, int flags);
1924 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
1925                                 const struct iovec *iov, loff_t offset,
1926                                 unsigned long nr_segs);
1927 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
1928 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
1929 extern void ext4_ind_truncate(struct inode *inode);
1930
1931 /* ioctl.c */
1932 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1933 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1934
1935 /* migrate.c */
1936 extern int ext4_ext_migrate(struct inode *);
1937
1938 /* namei.c */
1939 extern int ext4_orphan_add(handle_t *, struct inode *);
1940 extern int ext4_orphan_del(handle_t *, struct inode *);
1941 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1942                                 __u32 start_minor_hash, __u32 *next_hash);
1943
1944 /* resize.c */
1945 extern int ext4_group_add(struct super_block *sb,
1946                                 struct ext4_new_group_data *input);
1947 extern int ext4_group_extend(struct super_block *sb,
1948                                 struct ext4_super_block *es,
1949                                 ext4_fsblk_t n_blocks_count);
1950 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
1951
1952 /* super.c */
1953 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
1954 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
1955 extern void ext4_kvfree(void *ptr);
1956 extern __printf(4, 5)
1957 void __ext4_error(struct super_block *, const char *, unsigned int,
1958                   const char *, ...);
1959 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
1960                                                      __LINE__, ## message)
1961 extern __printf(5, 6)
1962 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
1963                       const char *, ...);
1964 extern __printf(5, 6)
1965 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
1966                      const char *, ...);
1967 extern void __ext4_std_error(struct super_block *, const char *,
1968                              unsigned int, int);
1969 extern __printf(4, 5)
1970 void __ext4_abort(struct super_block *, const char *, unsigned int,
1971                   const char *, ...);
1972 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
1973                                                        __LINE__, ## message)
1974 extern __printf(4, 5)
1975 void __ext4_warning(struct super_block *, const char *, unsigned int,
1976                     const char *, ...);
1977 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
1978                                                        __LINE__, ## message)
1979 extern __printf(3, 4)
1980 void ext4_msg(struct super_block *, const char *, const char *, ...);
1981 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
1982                            const char *, unsigned int, const char *);
1983 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
1984                                                        __LINE__, msg)
1985 extern __printf(7, 8)
1986 void __ext4_grp_locked_error(const char *, unsigned int,
1987                              struct super_block *, ext4_group_t,
1988                              unsigned long, ext4_fsblk_t,
1989                              const char *, ...);
1990 #define ext4_grp_locked_error(sb, grp, message...) \
1991         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1992 extern void ext4_update_dynamic_rev(struct super_block *sb);
1993 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1994                                         __u32 compat);
1995 extern int ext4_update_rocompat_feature(handle_t *handle,
1996                                         struct super_block *sb, __u32 rocompat);
1997 extern int ext4_update_incompat_feature(handle_t *handle,
1998                                         struct super_block *sb, __u32 incompat);
1999 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2000                                       struct ext4_group_desc *bg);
2001 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2002                                       struct ext4_group_desc *bg);
2003 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2004                                      struct ext4_group_desc *bg);
2005 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2006                                       struct ext4_group_desc *bg);
2007 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2008                                  struct ext4_group_desc *bg);
2009 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2010                                 struct ext4_group_desc *bg);
2011 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2012                                    struct ext4_group_desc *bg);
2013 extern void ext4_block_bitmap_set(struct super_block *sb,
2014                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2015 extern void ext4_inode_bitmap_set(struct super_block *sb,
2016                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2017 extern void ext4_inode_table_set(struct super_block *sb,
2018                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2019 extern void ext4_free_group_clusters_set(struct super_block *sb,
2020                                          struct ext4_group_desc *bg,
2021                                          __u32 count);
2022 extern void ext4_free_inodes_set(struct super_block *sb,
2023                                 struct ext4_group_desc *bg, __u32 count);
2024 extern void ext4_used_dirs_set(struct super_block *sb,
2025                                 struct ext4_group_desc *bg, __u32 count);
2026 extern void ext4_itable_unused_set(struct super_block *sb,
2027                                    struct ext4_group_desc *bg, __u32 count);
2028 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
2029                                    struct ext4_group_desc *gdp);
2030 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
2031                                        struct ext4_group_desc *gdp);
2032
2033 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2034 {
2035         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2036                 le32_to_cpu(es->s_blocks_count_lo);
2037 }
2038
2039 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2040 {
2041         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2042                 le32_to_cpu(es->s_r_blocks_count_lo);
2043 }
2044
2045 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2046 {
2047         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2048                 le32_to_cpu(es->s_free_blocks_count_lo);
2049 }
2050
2051 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2052                                          ext4_fsblk_t blk)
2053 {
2054         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2055         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2056 }
2057
2058 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2059                                               ext4_fsblk_t blk)
2060 {
2061         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2062         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2063 }
2064
2065 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2066                                            ext4_fsblk_t blk)
2067 {
2068         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2069         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2070 }
2071
2072 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2073 {
2074         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2075                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2076                         le32_to_cpu(raw_inode->i_size_lo);
2077         else
2078                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2079 }
2080
2081 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2082 {
2083         raw_inode->i_size_lo = cpu_to_le32(i_size);
2084         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2085 }
2086
2087 static inline
2088 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2089                                             ext4_group_t group)
2090 {
2091          struct ext4_group_info ***grp_info;
2092          long indexv, indexh;
2093          grp_info = EXT4_SB(sb)->s_group_info;
2094          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2095          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2096          return grp_info[indexv][indexh];
2097 }
2098
2099 /*
2100  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2101  * the locking protocol documented in the comments of ext4_group_add()
2102  * in resize.c
2103  */
2104 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2105 {
2106         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2107
2108         smp_rmb();
2109         return ngroups;
2110 }
2111
2112 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2113                                              ext4_group_t block_group)
2114 {
2115         return block_group >> sbi->s_log_groups_per_flex;
2116 }
2117
2118 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2119 {
2120         return 1 << sbi->s_log_groups_per_flex;
2121 }
2122
2123 #define ext4_std_error(sb, errno)                               \
2124 do {                                                            \
2125         if ((errno))                                            \
2126                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2127 } while (0)
2128
2129 #ifdef CONFIG_SMP
2130 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2131  * counters. So we need to make sure we have free clusters more
2132  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2133  */
2134 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2135 #else
2136 #define EXT4_FREECLUSTERS_WATERMARK 0
2137 #endif
2138
2139 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2140 {
2141         /*
2142          * XXX: replace with spinlock if seen contended -bzzz
2143          */
2144         down_write(&EXT4_I(inode)->i_data_sem);
2145         if (newsize > EXT4_I(inode)->i_disksize)
2146                 EXT4_I(inode)->i_disksize = newsize;
2147         up_write(&EXT4_I(inode)->i_data_sem);
2148         return ;
2149 }
2150
2151 struct ext4_group_info {
2152         unsigned long   bb_state;
2153         struct rb_root  bb_free_root;
2154         ext4_grpblk_t   bb_first_free;  /* first free block */
2155         ext4_grpblk_t   bb_free;        /* total free blocks */
2156         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2157         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2158         struct          list_head bb_prealloc_list;
2159 #ifdef DOUBLE_CHECK
2160         void            *bb_bitmap;
2161 #endif
2162         struct rw_semaphore alloc_sem;
2163         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2164                                          * regions, index is order.
2165                                          * bb_counters[3] = 5 means
2166                                          * 5 free 8-block regions. */
2167 };
2168
2169 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2170 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2171
2172 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2173         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2174
2175 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2176         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2177 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2178         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2179 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2180         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2181
2182 #define EXT4_MAX_CONTENTION             8
2183 #define EXT4_CONTENTION_THRESHOLD       2
2184
2185 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2186                                               ext4_group_t group)
2187 {
2188         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2189 }
2190
2191 /*
2192  * Returns true if the filesystem is busy enough that attempts to
2193  * access the block group locks has run into contention.
2194  */
2195 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2196 {
2197         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2198 }
2199
2200 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2201 {
2202         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2203         if (spin_trylock(lock))
2204                 /*
2205                  * We're able to grab the lock right away, so drop the
2206                  * lock contention counter.
2207                  */
2208                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2209         else {
2210                 /*
2211                  * The lock is busy, so bump the contention counter,
2212                  * and then wait on the spin lock.
2213                  */
2214                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2215                                   EXT4_MAX_CONTENTION);
2216                 spin_lock(lock);
2217         }
2218 }
2219
2220 static inline void ext4_unlock_group(struct super_block *sb,
2221                                         ext4_group_t group)
2222 {
2223         spin_unlock(ext4_group_lock_ptr(sb, group));
2224 }
2225
2226 static inline void ext4_mark_super_dirty(struct super_block *sb)
2227 {
2228         if (EXT4_SB(sb)->s_journal == NULL)
2229                 sb->s_dirt =1;
2230 }
2231
2232 /*
2233  * Block validity checking
2234  */
2235 #define ext4_check_indirect_blockref(inode, bh)                         \
2236         ext4_check_blockref(__func__, __LINE__, inode,                  \
2237                             (__le32 *)(bh)->b_data,                     \
2238                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2239
2240 #define ext4_ind_check_inode(inode)                                     \
2241         ext4_check_blockref(__func__, __LINE__, inode,                  \
2242                             EXT4_I(inode)->i_data,                      \
2243                             EXT4_NDIR_BLOCKS)
2244
2245 /*
2246  * Inodes and files operations
2247  */
2248
2249 /* dir.c */
2250 extern const struct file_operations ext4_dir_operations;
2251
2252 /* file.c */
2253 extern const struct inode_operations ext4_file_inode_operations;
2254 extern const struct file_operations ext4_file_operations;
2255 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2256
2257 /* namei.c */
2258 extern const struct inode_operations ext4_dir_inode_operations;
2259 extern const struct inode_operations ext4_special_inode_operations;
2260 extern struct dentry *ext4_get_parent(struct dentry *child);
2261
2262 /* symlink.c */
2263 extern const struct inode_operations ext4_symlink_inode_operations;
2264 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2265
2266 /* block_validity */
2267 extern void ext4_release_system_zone(struct super_block *sb);
2268 extern int ext4_setup_system_zone(struct super_block *sb);
2269 extern int __init ext4_init_system_zone(void);
2270 extern void ext4_exit_system_zone(void);
2271 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2272                                  ext4_fsblk_t start_blk,
2273                                  unsigned int count);
2274 extern int ext4_check_blockref(const char *, unsigned int,
2275                                struct inode *, __le32 *, unsigned int);
2276
2277 /* extents.c */
2278 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2279 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2280 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2281                                        int chunk);
2282 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2283                                struct ext4_map_blocks *map, int flags);
2284 extern void ext4_ext_truncate(struct inode *);
2285 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2286                                 loff_t length);
2287 extern void ext4_ext_init(struct super_block *);
2288 extern void ext4_ext_release(struct super_block *);
2289 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2290                           loff_t len);
2291 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2292                           ssize_t len);
2293 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2294                            struct ext4_map_blocks *map, int flags);
2295 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2296                         __u64 start, __u64 len);
2297 /* move_extent.c */
2298 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2299                              __u64 start_orig, __u64 start_donor,
2300                              __u64 len, __u64 *moved_len);
2301
2302 /* page-io.c */
2303 extern int __init ext4_init_pageio(void);
2304 extern void ext4_exit_pageio(void);
2305 extern void ext4_ioend_wait(struct inode *);
2306 extern void ext4_free_io_end(ext4_io_end_t *io);
2307 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2308 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2309 extern void ext4_io_submit(struct ext4_io_submit *io);
2310 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2311                                struct page *page,
2312                                int len,
2313                                struct writeback_control *wbc);
2314
2315 /* mmp.c */
2316 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2317
2318 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2319 enum ext4_state_bits {
2320         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2321           = BH_JBDPrivateStart,
2322         BH_AllocFromCluster,    /* allocated blocks were part of already
2323                                  * allocated cluster. Note that this flag will
2324                                  * never, ever appear in a buffer_head's state
2325                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2326                                  * this is used. */
2327         BH_Da_Mapped,   /* Delayed allocated block that now has a mapping. This
2328                          * flag is set when ext4_map_blocks is called on a
2329                          * delayed allocated block to get its real mapping. */
2330 };
2331
2332 BUFFER_FNS(Uninit, uninit)
2333 TAS_BUFFER_FNS(Uninit, uninit)
2334 BUFFER_FNS(Da_Mapped, da_mapped)
2335
2336 /*
2337  * Add new method to test wether block and inode bitmaps are properly
2338  * initialized. With uninit_bg reading the block from disk is not enough
2339  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2340  */
2341 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2342
2343 static inline int bitmap_uptodate(struct buffer_head *bh)
2344 {
2345         return (buffer_uptodate(bh) &&
2346                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2347 }
2348 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2349 {
2350         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2351 }
2352
2353 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2354
2355 /* For ioend & aio unwritten conversion wait queues */
2356 #define EXT4_WQ_HASH_SZ         37
2357 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2358                                             EXT4_WQ_HASH_SZ])
2359 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2360                                              EXT4_WQ_HASH_SZ])
2361 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2362 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2363
2364 #define EXT4_RESIZING   0
2365 extern int ext4_resize_begin(struct super_block *sb);
2366 extern void ext4_resize_end(struct super_block *sb);
2367
2368 #endif  /* __KERNEL__ */
2369
2370 #include "ext4_extents.h"
2371
2372 #endif  /* _EXT4_H */