- Update to 3.3-rc2.
[linux-flexiantxendom0-3.2.10.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(f, a...)     do {} while (0)
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
188 struct ext4_io_page {
189         struct page     *p_page;
190         atomic_t        p_count;
191 };
192
193 #define MAX_IO_PAGES 128
194
195 typedef struct ext4_io_end {
196         struct list_head        list;           /* per-file finished IO list */
197         struct inode            *inode;         /* file being written to */
198         unsigned int            flag;           /* unwritten or not */
199         struct page             *page;          /* page struct for buffer write */
200         loff_t                  offset;         /* offset in the file */
201         ssize_t                 size;           /* size of the extent */
202         struct work_struct      work;           /* data work queue */
203         struct kiocb            *iocb;          /* iocb struct for AIO */
204         int                     result;         /* error value for AIO */
205         int                     num_io_pages;
206         struct ext4_io_page     *pages[MAX_IO_PAGES];
207 } ext4_io_end_t;
208
209 struct ext4_io_submit {
210         int                     io_op;
211         struct bio              *io_bio;
212         ext4_io_end_t           *io_end;
213         struct ext4_io_page     *io_page;
214         sector_t                io_next_block;
215 };
216
217 /*
218  * Special inodes numbers
219  */
220 #define EXT4_BAD_INO             1      /* Bad blocks inode */
221 #define EXT4_ROOT_INO            2      /* Root inode */
222 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
223 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
224 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
225 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
226 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
227 #define EXT4_JOURNAL_INO         8      /* Journal inode */
228
229 /* First non-reserved inode for old ext4 filesystems */
230 #define EXT4_GOOD_OLD_FIRST_INO 11
231
232 /*
233  * Maximal count of links to a file
234  */
235 #define EXT4_LINK_MAX           65000
236
237 /*
238  * Macro-instructions used to manage several block sizes
239  */
240 #define EXT4_MIN_BLOCK_SIZE             1024
241 #define EXT4_MAX_BLOCK_SIZE             65536
242 #define EXT4_MIN_BLOCK_LOG_SIZE         10
243 #define EXT4_MAX_BLOCK_LOG_SIZE         16
244 #ifdef __KERNEL__
245 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
246 #else
247 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
248 #endif
249 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
250 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
251                                          EXT4_SB(s)->s_cluster_bits)
252 #ifdef __KERNEL__
253 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
254 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
255 #else
256 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
257 #endif
258 #ifdef __KERNEL__
259 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
260 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
261 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
262 #else
263 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
264                                  EXT4_GOOD_OLD_INODE_SIZE : \
265                                  (s)->s_inode_size)
266 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
267                                  EXT4_GOOD_OLD_FIRST_INO : \
268                                  (s)->s_first_ino)
269 #endif
270 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
271
272 /* Translate a block number to a cluster number */
273 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
274 /* Translate a cluster number to a block number */
275 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
276 /* Translate # of blks to # of clusters */
277 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
278                                  (sbi)->s_cluster_bits)
279
280 /*
281  * Structure of a blocks group descriptor
282  */
283 struct ext4_group_desc
284 {
285         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
286         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
287         __le32  bg_inode_table_lo;      /* Inodes table block */
288         __le16  bg_free_blocks_count_lo;/* Free blocks count */
289         __le16  bg_free_inodes_count_lo;/* Free inodes count */
290         __le16  bg_used_dirs_count_lo;  /* Directories count */
291         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
292         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
293         __le16  bg_itable_unused_lo;    /* Unused inodes count */
294         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
295         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
296         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
297         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
298         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
299         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
300         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
301         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
302         __u32   bg_reserved2[3];
303 };
304
305 /*
306  * Structure of a flex block group info
307  */
308
309 struct flex_groups {
310         atomic_t free_inodes;
311         atomic_t free_clusters;
312         atomic_t used_dirs;
313 };
314
315 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
316 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
317 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
318
319 /*
320  * Macro-instructions used to manage group descriptors
321  */
322 #define EXT4_MIN_DESC_SIZE              32
323 #define EXT4_MIN_DESC_SIZE_64BIT        64
324 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
325 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
326 #ifdef __KERNEL__
327 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
328 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
329 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
330 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
331 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
332 #else
333 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
334 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
335 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
336 #endif
337
338 /*
339  * Constants relative to the data blocks
340  */
341 #define EXT4_NDIR_BLOCKS                12
342 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
343 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
344 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
345 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
346
347 /*
348  * Inode flags
349  */
350 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
351 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
352 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
353 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
354 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
355 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
356 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
357 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
358 /* Reserved for compression usage... */
359 #define EXT4_DIRTY_FL                   0x00000100
360 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
361 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
362 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
363 /* End compression flags --- maybe not all used */
364 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
365 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
366 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
367 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
368 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
369 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
370 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
371 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
372 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
373 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
374 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
375
376 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
377 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
378
379 /* Flags that should be inherited by new inodes from their parent. */
380 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
381                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
382                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
383                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
384
385 /* Flags that are appropriate for regular files (all but dir-specific ones). */
386 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
387
388 /* Flags that are appropriate for non-directories/regular files. */
389 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
390
391 /* Mask out flags that are inappropriate for the given type of inode. */
392 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
393 {
394         if (S_ISDIR(mode))
395                 return flags;
396         else if (S_ISREG(mode))
397                 return flags & EXT4_REG_FLMASK;
398         else
399                 return flags & EXT4_OTHER_FLMASK;
400 }
401
402 /*
403  * Inode flags used for atomic set/get
404  */
405 enum {
406         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
407         EXT4_INODE_UNRM         = 1,    /* Undelete */
408         EXT4_INODE_COMPR        = 2,    /* Compress file */
409         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
410         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
411         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
412         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
413         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
414 /* Reserved for compression usage... */
415         EXT4_INODE_DIRTY        = 8,
416         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
417         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
418         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
419 /* End compression flags --- maybe not all used */
420         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
421         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
422         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
423         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
424         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
425         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
426         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
427         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
428         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
429         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
430         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
431 };
432
433 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
434 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
435         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
436                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
437
438 /*
439  * Since it's pretty easy to mix up bit numbers and hex values, and we
440  * can't do a compile-time test for ENUM values, we use a run-time
441  * test to make sure that EXT4_XXX_FL is consistent with respect to
442  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
443  * out so it won't cost any extra space in the compiled kernel image.
444  * But it's important that these values are the same, since we are
445  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
446  * must be consistent with the values of FS_XXX_FL defined in
447  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
448  * ext4 filesystems, and of course the values defined in e2fsprogs.
449  *
450  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
451  */
452 static inline void ext4_check_flag_values(void)
453 {
454         CHECK_FLAG_VALUE(SECRM);
455         CHECK_FLAG_VALUE(UNRM);
456         CHECK_FLAG_VALUE(COMPR);
457         CHECK_FLAG_VALUE(SYNC);
458         CHECK_FLAG_VALUE(IMMUTABLE);
459         CHECK_FLAG_VALUE(APPEND);
460         CHECK_FLAG_VALUE(NODUMP);
461         CHECK_FLAG_VALUE(NOATIME);
462         CHECK_FLAG_VALUE(DIRTY);
463         CHECK_FLAG_VALUE(COMPRBLK);
464         CHECK_FLAG_VALUE(NOCOMPR);
465         CHECK_FLAG_VALUE(ECOMPR);
466         CHECK_FLAG_VALUE(INDEX);
467         CHECK_FLAG_VALUE(IMAGIC);
468         CHECK_FLAG_VALUE(JOURNAL_DATA);
469         CHECK_FLAG_VALUE(NOTAIL);
470         CHECK_FLAG_VALUE(DIRSYNC);
471         CHECK_FLAG_VALUE(TOPDIR);
472         CHECK_FLAG_VALUE(HUGE_FILE);
473         CHECK_FLAG_VALUE(EXTENTS);
474         CHECK_FLAG_VALUE(EA_INODE);
475         CHECK_FLAG_VALUE(EOFBLOCKS);
476         CHECK_FLAG_VALUE(RESERVED);
477 }
478
479 /* Used to pass group descriptor data when online resize is done */
480 struct ext4_new_group_input {
481         __u32 group;            /* Group number for this data */
482         __u64 block_bitmap;     /* Absolute block number of block bitmap */
483         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
484         __u64 inode_table;      /* Absolute block number of inode table start */
485         __u32 blocks_count;     /* Total number of blocks in this group */
486         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
487         __u16 unused;
488 };
489
490 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
491 struct compat_ext4_new_group_input {
492         u32 group;
493         compat_u64 block_bitmap;
494         compat_u64 inode_bitmap;
495         compat_u64 inode_table;
496         u32 blocks_count;
497         u16 reserved_blocks;
498         u16 unused;
499 };
500 #endif
501
502 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
503 struct ext4_new_group_data {
504         __u32 group;
505         __u64 block_bitmap;
506         __u64 inode_bitmap;
507         __u64 inode_table;
508         __u32 blocks_count;
509         __u16 reserved_blocks;
510         __u16 unused;
511         __u32 free_blocks_count;
512 };
513
514 /* Indexes used to index group tables in ext4_new_group_data */
515 enum {
516         BLOCK_BITMAP = 0,       /* block bitmap */
517         INODE_BITMAP,           /* inode bitmap */
518         INODE_TABLE,            /* inode tables */
519         GROUP_TABLE_COUNT,
520 };
521
522 /*
523  * Flags used by ext4_map_blocks()
524  */
525         /* Allocate any needed blocks and/or convert an unitialized
526            extent to be an initialized ext4 */
527 #define EXT4_GET_BLOCKS_CREATE                  0x0001
528         /* Request the creation of an unitialized extent */
529 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
530 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
531                                                  EXT4_GET_BLOCKS_CREATE)
532         /* Caller is from the delayed allocation writeout path,
533            so set the magic i_delalloc_reserve_flag after taking the
534            inode allocation semaphore for */
535 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
536         /* caller is from the direct IO path, request to creation of an
537         unitialized extents if not allocated, split the uninitialized
538         extent if blocks has been preallocated already*/
539 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
540 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
541 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
542                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
543         /* Convert extent to initialized after IO complete */
544 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
545                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
546         /* Punch out blocks of an extent */
547 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
548         /* Don't normalize allocation size (used for fallocate) */
549 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
550         /* Request will not result in inode size update (user for fallocate) */
551 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
552
553 /*
554  * Flags used by ext4_free_blocks
555  */
556 #define EXT4_FREE_BLOCKS_METADATA       0x0001
557 #define EXT4_FREE_BLOCKS_FORGET         0x0002
558 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
559 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
560 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
561 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
562
563 /*
564  * Flags used by ext4_discard_partial_page_buffers
565  */
566 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
567
568 /*
569  * ioctl commands
570  */
571 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
572 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
573 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
574 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
575 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
576 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
577 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
578 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
579 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
580 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
581 #define EXT4_IOC_MIGRATE                _IO('f', 9)
582  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
583  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
584 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
585 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
586 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
587
588 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
589 /*
590  * ioctl commands in 32 bit emulation
591  */
592 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
593 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
594 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
595 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
596 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
597 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
598 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
599 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
600 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
601 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
602 #endif
603
604 /* Max physical block we can address w/o extents */
605 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
606
607 /*
608  * Structure of an inode on the disk
609  */
610 struct ext4_inode {
611         __le16  i_mode;         /* File mode */
612         __le16  i_uid;          /* Low 16 bits of Owner Uid */
613         __le32  i_size_lo;      /* Size in bytes */
614         __le32  i_atime;        /* Access time */
615         __le32  i_ctime;        /* Inode Change time */
616         __le32  i_mtime;        /* Modification time */
617         __le32  i_dtime;        /* Deletion Time */
618         __le16  i_gid;          /* Low 16 bits of Group Id */
619         __le16  i_links_count;  /* Links count */
620         __le32  i_blocks_lo;    /* Blocks count */
621         __le32  i_flags;        /* File flags */
622         union {
623                 struct {
624                         __le32  l_i_version;
625                 } linux1;
626                 struct {
627                         __u32  h_i_translator;
628                 } hurd1;
629                 struct {
630                         __u32  m_i_reserved1;
631                 } masix1;
632         } osd1;                         /* OS dependent 1 */
633         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
634         __le32  i_generation;   /* File version (for NFS) */
635         __le32  i_file_acl_lo;  /* File ACL */
636         __le32  i_size_high;
637         __le32  i_obso_faddr;   /* Obsoleted fragment address */
638         union {
639                 struct {
640                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
641                         __le16  l_i_file_acl_high;
642                         __le16  l_i_uid_high;   /* these 2 fields */
643                         __le16  l_i_gid_high;   /* were reserved2[0] */
644                         __u32   l_i_reserved2;
645                 } linux2;
646                 struct {
647                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
648                         __u16   h_i_mode_high;
649                         __u16   h_i_uid_high;
650                         __u16   h_i_gid_high;
651                         __u32   h_i_author;
652                 } hurd2;
653                 struct {
654                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
655                         __le16  m_i_file_acl_high;
656                         __u32   m_i_reserved2[2];
657                 } masix2;
658         } osd2;                         /* OS dependent 2 */
659         __le16  i_extra_isize;
660         __le16  i_pad1;
661         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
662         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
663         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
664         __le32  i_crtime;       /* File Creation time */
665         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
666         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
667 };
668
669 struct move_extent {
670         __u32 reserved;         /* should be zero */
671         __u32 donor_fd;         /* donor file descriptor */
672         __u64 orig_start;       /* logical start offset in block for orig */
673         __u64 donor_start;      /* logical start offset in block for donor */
674         __u64 len;              /* block length to be moved */
675         __u64 moved_len;        /* moved block length */
676 };
677
678 #define EXT4_EPOCH_BITS 2
679 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
680 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
681
682 /*
683  * Extended fields will fit into an inode if the filesystem was formatted
684  * with large inodes (-I 256 or larger) and there are not currently any EAs
685  * consuming all of the available space. For new inodes we always reserve
686  * enough space for the kernel's known extended fields, but for inodes
687  * created with an old kernel this might not have been the case. None of
688  * the extended inode fields is critical for correct filesystem operation.
689  * This macro checks if a certain field fits in the inode. Note that
690  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
691  */
692 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
693         ((offsetof(typeof(*ext4_inode), field) +        \
694           sizeof((ext4_inode)->field))                  \
695         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
696             (einode)->i_extra_isize))                   \
697
698 static inline __le32 ext4_encode_extra_time(struct timespec *time)
699 {
700        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
701                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
702                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
703 }
704
705 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
706 {
707        if (sizeof(time->tv_sec) > 4)
708                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
709                                << 32;
710        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
711 }
712
713 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
714 do {                                                                           \
715         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
716         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
717                 (raw_inode)->xtime ## _extra =                                 \
718                                 ext4_encode_extra_time(&(inode)->xtime);       \
719 } while (0)
720
721 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
722 do {                                                                           \
723         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
724                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
725         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
726                 (raw_inode)->xtime ## _extra =                                 \
727                                 ext4_encode_extra_time(&(einode)->xtime);      \
728 } while (0)
729
730 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
731 do {                                                                           \
732         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
733         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
734                 ext4_decode_extra_time(&(inode)->xtime,                        \
735                                        raw_inode->xtime ## _extra);            \
736         else                                                                   \
737                 (inode)->xtime.tv_nsec = 0;                                    \
738 } while (0)
739
740 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
741 do {                                                                           \
742         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
743                 (einode)->xtime.tv_sec =                                       \
744                         (signed)le32_to_cpu((raw_inode)->xtime);               \
745         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
746                 ext4_decode_extra_time(&(einode)->xtime,                       \
747                                        raw_inode->xtime ## _extra);            \
748         else                                                                   \
749                 (einode)->xtime.tv_nsec = 0;                                   \
750 } while (0)
751
752 #define i_disk_version osd1.linux1.l_i_version
753
754 #if defined(__KERNEL__) || defined(__linux__)
755 #define i_reserved1     osd1.linux1.l_i_reserved1
756 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
757 #define i_blocks_high   osd2.linux2.l_i_blocks_high
758 #define i_uid_low       i_uid
759 #define i_gid_low       i_gid
760 #define i_uid_high      osd2.linux2.l_i_uid_high
761 #define i_gid_high      osd2.linux2.l_i_gid_high
762 #define i_reserved2     osd2.linux2.l_i_reserved2
763
764 #elif defined(__GNU__)
765
766 #define i_translator    osd1.hurd1.h_i_translator
767 #define i_uid_high      osd2.hurd2.h_i_uid_high
768 #define i_gid_high      osd2.hurd2.h_i_gid_high
769 #define i_author        osd2.hurd2.h_i_author
770
771 #elif defined(__masix__)
772
773 #define i_reserved1     osd1.masix1.m_i_reserved1
774 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
775 #define i_reserved2     osd2.masix2.m_i_reserved2
776
777 #endif /* defined(__KERNEL__) || defined(__linux__) */
778
779 /*
780  * storage for cached extent
781  * If ec_len == 0, then the cache is invalid.
782  * If ec_start == 0, then the cache represents a gap (null mapping)
783  */
784 struct ext4_ext_cache {
785         ext4_fsblk_t    ec_start;
786         ext4_lblk_t     ec_block;
787         __u32           ec_len; /* must be 32bit to return holes */
788 };
789
790 /*
791  * fourth extended file system inode data in memory
792  */
793 struct ext4_inode_info {
794         __le32  i_data[15];     /* unconverted */
795         __u32   i_dtime;
796         ext4_fsblk_t    i_file_acl;
797
798         /*
799          * i_block_group is the number of the block group which contains
800          * this file's inode.  Constant across the lifetime of the inode,
801          * it is ued for making block allocation decisions - we try to
802          * place a file's data blocks near its inode block, and new inodes
803          * near to their parent directory's inode.
804          */
805         ext4_group_t    i_block_group;
806         ext4_lblk_t     i_dir_start_lookup;
807 #if (BITS_PER_LONG < 64)
808         unsigned long   i_state_flags;          /* Dynamic state flags */
809 #endif
810         unsigned long   i_flags;
811
812 #ifdef CONFIG_EXT4_FS_XATTR
813         /*
814          * Extended attributes can be read independently of the main file
815          * data. Taking i_mutex even when reading would cause contention
816          * between readers of EAs and writers of regular file data, so
817          * instead we synchronize on xattr_sem when reading or changing
818          * EAs.
819          */
820         struct rw_semaphore xattr_sem;
821 #endif
822
823         struct list_head i_orphan;      /* unlinked but open inodes */
824
825         /*
826          * i_disksize keeps track of what the inode size is ON DISK, not
827          * in memory.  During truncate, i_size is set to the new size by
828          * the VFS prior to calling ext4_truncate(), but the filesystem won't
829          * set i_disksize to 0 until the truncate is actually under way.
830          *
831          * The intent is that i_disksize always represents the blocks which
832          * are used by this file.  This allows recovery to restart truncate
833          * on orphans if we crash during truncate.  We actually write i_disksize
834          * into the on-disk inode when writing inodes out, instead of i_size.
835          *
836          * The only time when i_disksize and i_size may be different is when
837          * a truncate is in progress.  The only things which change i_disksize
838          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
839          */
840         loff_t  i_disksize;
841
842         /*
843          * i_data_sem is for serialising ext4_truncate() against
844          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
845          * data tree are chopped off during truncate. We can't do that in
846          * ext4 because whenever we perform intermediate commits during
847          * truncate, the inode and all the metadata blocks *must* be in a
848          * consistent state which allows truncation of the orphans to restart
849          * during recovery.  Hence we must fix the get_block-vs-truncate race
850          * by other means, so we have i_data_sem.
851          */
852         struct rw_semaphore i_data_sem;
853         struct inode vfs_inode;
854         struct jbd2_inode *jinode;
855
856         struct ext4_ext_cache i_cached_extent;
857         /*
858          * File creation time. Its function is same as that of
859          * struct timespec i_{a,c,m}time in the generic inode.
860          */
861         struct timespec i_crtime;
862
863         /* mballoc */
864         struct list_head i_prealloc_list;
865         spinlock_t i_prealloc_lock;
866
867         /* ialloc */
868         ext4_group_t    i_last_alloc_group;
869
870         /* allocation reservation info for delalloc */
871         /* In case of bigalloc, these refer to clusters rather than blocks */
872         unsigned int i_reserved_data_blocks;
873         unsigned int i_reserved_meta_blocks;
874         unsigned int i_allocated_meta_blocks;
875         ext4_lblk_t i_da_metadata_calc_last_lblock;
876         int i_da_metadata_calc_len;
877
878         /* on-disk additional length */
879         __u16 i_extra_isize;
880
881 #ifdef CONFIG_QUOTA
882         /* quota space reservation, managed internally by quota code */
883         qsize_t i_reserved_quota;
884 #endif
885
886         /* completed IOs that might need unwritten extents handling */
887         struct list_head i_completed_io_list;
888         spinlock_t i_completed_io_lock;
889         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
890         /* current io_end structure for async DIO write*/
891         ext4_io_end_t *cur_aio_dio;
892         atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
893
894         spinlock_t i_block_reservation_lock;
895
896         /*
897          * Transactions that contain inode's metadata needed to complete
898          * fsync and fdatasync, respectively.
899          */
900         tid_t i_sync_tid;
901         tid_t i_datasync_tid;
902 #ifdef CONFIG_EXT4_FS_RICHACL
903         struct richacl   *i_richacl;
904 #endif
905
906 };
907
908 /*
909  * File system states
910  */
911 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
912 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
913 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
914
915 /*
916  * Misc. filesystem flags
917  */
918 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
919 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
920 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
921
922 /*
923  * Mount flags
924  */
925 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
926 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
927 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
928 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
929 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
930 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
931 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
932 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
933 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
934 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
935 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
936 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
937 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
938 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
939 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
940 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
941 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
942 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
943 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
944 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
945 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
946 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
947 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
948 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
949 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
950 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
951 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
952 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
953 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
954
955 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
956                                                       specified delalloc */
957
958 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
959                                                 ~EXT4_MOUNT_##opt
960 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
961                                                 EXT4_MOUNT_##opt
962 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
963                                          EXT4_MOUNT_##opt)
964
965 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
966                                                 ~EXT4_MOUNT2_##opt
967 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
968                                                 EXT4_MOUNT2_##opt
969 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
970                                          EXT4_MOUNT2_##opt)
971
972 #define ext4_test_and_set_bit           __test_and_set_bit_le
973 #define ext4_set_bit                    __set_bit_le
974 #define ext4_set_bit_atomic             ext2_set_bit_atomic
975 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
976 #define ext4_clear_bit                  __clear_bit_le
977 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
978 #define ext4_test_bit                   test_bit_le
979 #define ext4_find_next_zero_bit         find_next_zero_bit_le
980 #define ext4_find_next_bit              find_next_bit_le
981
982 extern void ext4_set_bits(void *bm, int cur, int len);
983
984 /*
985  * Maximal mount counts between two filesystem checks
986  */
987 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
988 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
989
990 /*
991  * Behaviour when detecting errors
992  */
993 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
994 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
995 #define EXT4_ERRORS_PANIC               3       /* Panic */
996 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
997
998 /*
999  * Structure of the super block
1000  */
1001 struct ext4_super_block {
1002 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1003         __le32  s_blocks_count_lo;      /* Blocks count */
1004         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1005         __le32  s_free_blocks_count_lo; /* Free blocks count */
1006 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1007         __le32  s_first_data_block;     /* First Data Block */
1008         __le32  s_log_block_size;       /* Block size */
1009         __le32  s_log_cluster_size;     /* Allocation cluster size */
1010 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1011         __le32  s_clusters_per_group;   /* # Clusters per group */
1012         __le32  s_inodes_per_group;     /* # Inodes per group */
1013         __le32  s_mtime;                /* Mount time */
1014 /*30*/  __le32  s_wtime;                /* Write time */
1015         __le16  s_mnt_count;            /* Mount count */
1016         __le16  s_max_mnt_count;        /* Maximal mount count */
1017         __le16  s_magic;                /* Magic signature */
1018         __le16  s_state;                /* File system state */
1019         __le16  s_errors;               /* Behaviour when detecting errors */
1020         __le16  s_minor_rev_level;      /* minor revision level */
1021 /*40*/  __le32  s_lastcheck;            /* time of last check */
1022         __le32  s_checkinterval;        /* max. time between checks */
1023         __le32  s_creator_os;           /* OS */
1024         __le32  s_rev_level;            /* Revision level */
1025 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1026         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1027         /*
1028          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1029          *
1030          * Note: the difference between the compatible feature set and
1031          * the incompatible feature set is that if there is a bit set
1032          * in the incompatible feature set that the kernel doesn't
1033          * know about, it should refuse to mount the filesystem.
1034          *
1035          * e2fsck's requirements are more strict; if it doesn't know
1036          * about a feature in either the compatible or incompatible
1037          * feature set, it must abort and not try to meddle with
1038          * things it doesn't understand...
1039          */
1040         __le32  s_first_ino;            /* First non-reserved inode */
1041         __le16  s_inode_size;           /* size of inode structure */
1042         __le16  s_block_group_nr;       /* block group # of this superblock */
1043         __le32  s_feature_compat;       /* compatible feature set */
1044 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1045         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1046 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1047 /*78*/  char    s_volume_name[16];      /* volume name */
1048 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1049 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1050         /*
1051          * Performance hints.  Directory preallocation should only
1052          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1053          */
1054         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1055         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1056         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1057         /*
1058          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1059          */
1060 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1061 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1062         __le32  s_journal_dev;          /* device number of journal file */
1063         __le32  s_last_orphan;          /* start of list of inodes to delete */
1064         __le32  s_hash_seed[4];         /* HTREE hash seed */
1065         __u8    s_def_hash_version;     /* Default hash version to use */
1066         __u8    s_jnl_backup_type;
1067         __le16  s_desc_size;            /* size of group descriptor */
1068 /*100*/ __le32  s_default_mount_opts;
1069         __le32  s_first_meta_bg;        /* First metablock block group */
1070         __le32  s_mkfs_time;            /* When the filesystem was created */
1071         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1072         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1073 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1074         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1075         __le32  s_free_blocks_count_hi; /* Free blocks count */
1076         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1077         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1078         __le32  s_flags;                /* Miscellaneous flags */
1079         __le16  s_raid_stride;          /* RAID stride */
1080         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1081         __le64  s_mmp_block;            /* Block for multi-mount protection */
1082         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1083         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1084         __u8    s_reserved_char_pad;
1085         __le16  s_reserved_pad;
1086         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1087         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1088         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1089         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1090                                               snapshot's future use */
1091         __le32  s_snapshot_list;        /* inode number of the head of the
1092                                            on-disk snapshot list */
1093 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1094         __le32  s_error_count;          /* number of fs errors */
1095         __le32  s_first_error_time;     /* first time an error happened */
1096         __le32  s_first_error_ino;      /* inode involved in first error */
1097         __le64  s_first_error_block;    /* block involved of first error */
1098         __u8    s_first_error_func[32]; /* function where the error happened */
1099         __le32  s_first_error_line;     /* line number where error happened */
1100         __le32  s_last_error_time;      /* most recent time of an error */
1101         __le32  s_last_error_ino;       /* inode involved in last error */
1102         __le32  s_last_error_line;      /* line number where error happened */
1103         __le64  s_last_error_block;     /* block involved of last error */
1104         __u8    s_last_error_func[32];  /* function where the error happened */
1105 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1106         __u8    s_mount_opts[64];
1107         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1108         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1109         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1110         __le32  s_reserved[109];        /* Padding to the end of the block */
1111 };
1112
1113 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1114
1115 #ifdef __KERNEL__
1116
1117 /*
1118  * run-time mount flags
1119  */
1120 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1121 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1122
1123 /*
1124  * fourth extended-fs super-block data in memory
1125  */
1126 struct ext4_sb_info {
1127         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1128         unsigned long s_inodes_per_block;/* Number of inodes per block */
1129         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1130         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1131         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1132         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1133         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1134         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1135         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1136         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1137         unsigned long s_overhead_last;  /* Last calculated overhead */
1138         unsigned long s_blocks_last;    /* Last seen block count */
1139         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1140         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1141         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1142         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1143         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1144         struct buffer_head **s_group_desc;
1145         unsigned int s_mount_opt;
1146         unsigned int s_mount_opt2;
1147         unsigned int s_mount_flags;
1148         ext4_fsblk_t s_sb_block;
1149         uid_t s_resuid;
1150         gid_t s_resgid;
1151         unsigned short s_mount_state;
1152         unsigned short s_pad;
1153         int s_addr_per_block_bits;
1154         int s_desc_per_block_bits;
1155         int s_inode_size;
1156         int s_first_ino;
1157         unsigned int s_inode_readahead_blks;
1158         unsigned int s_inode_goal;
1159         spinlock_t s_next_gen_lock;
1160         u32 s_next_generation;
1161         u32 s_hash_seed[4];
1162         int s_def_hash_version;
1163         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1164         struct percpu_counter s_freeclusters_counter;
1165         struct percpu_counter s_freeinodes_counter;
1166         struct percpu_counter s_dirs_counter;
1167         struct percpu_counter s_dirtyclusters_counter;
1168         struct blockgroup_lock *s_blockgroup_lock;
1169         struct proc_dir_entry *s_proc;
1170         struct kobject s_kobj;
1171         struct completion s_kobj_unregister;
1172
1173         /* Journaling */
1174         struct journal_s *s_journal;
1175         struct list_head s_orphan;
1176         struct mutex s_orphan_lock;
1177         unsigned long s_resize_flags;           /* Flags indicating if there
1178                                                    is a resizer */
1179         unsigned long s_commit_interval;
1180         u32 s_max_batch_time;
1181         u32 s_min_batch_time;
1182         struct block_device *journal_bdev;
1183 #ifdef CONFIG_QUOTA
1184         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1185         int s_jquota_fmt;                       /* Format of quota to use */
1186 #endif
1187         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1188         struct rb_root system_blks;
1189
1190 #ifdef EXTENTS_STATS
1191         /* ext4 extents stats */
1192         unsigned long s_ext_min;
1193         unsigned long s_ext_max;
1194         unsigned long s_depth_max;
1195         spinlock_t s_ext_stats_lock;
1196         unsigned long s_ext_blocks;
1197         unsigned long s_ext_extents;
1198 #endif
1199         /* ext4 extent cache stats */
1200         unsigned long extent_cache_hits;
1201         unsigned long extent_cache_misses;
1202
1203         /* for buddy allocator */
1204         struct ext4_group_info ***s_group_info;
1205         struct inode *s_buddy_cache;
1206         spinlock_t s_md_lock;
1207         unsigned short *s_mb_offsets;
1208         unsigned int *s_mb_maxs;
1209
1210         /* tunables */
1211         unsigned long s_stripe;
1212         unsigned int s_mb_stream_request;
1213         unsigned int s_mb_max_to_scan;
1214         unsigned int s_mb_min_to_scan;
1215         unsigned int s_mb_stats;
1216         unsigned int s_mb_order2_reqs;
1217         unsigned int s_mb_group_prealloc;
1218         unsigned int s_max_writeback_mb_bump;
1219         /* where last allocation was done - for stream allocation */
1220         unsigned long s_mb_last_group;
1221         unsigned long s_mb_last_start;
1222
1223         /* stats for buddy allocator */
1224         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1225         atomic_t s_bal_success; /* we found long enough chunks */
1226         atomic_t s_bal_allocated;       /* in blocks */
1227         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1228         atomic_t s_bal_goals;   /* goal hits */
1229         atomic_t s_bal_breaks;  /* too long searches */
1230         atomic_t s_bal_2orders; /* 2^order hits */
1231         spinlock_t s_bal_lock;
1232         unsigned long s_mb_buddies_generated;
1233         unsigned long long s_mb_generation_time;
1234         atomic_t s_mb_lost_chunks;
1235         atomic_t s_mb_preallocated;
1236         atomic_t s_mb_discarded;
1237         atomic_t s_lock_busy;
1238
1239         /* locality groups */
1240         struct ext4_locality_group __percpu *s_locality_groups;
1241
1242         /* for write statistics */
1243         unsigned long s_sectors_written_start;
1244         u64 s_kbytes_written;
1245
1246         unsigned int s_log_groups_per_flex;
1247         struct flex_groups *s_flex_groups;
1248
1249         /* workqueue for dio unwritten */
1250         struct workqueue_struct *dio_unwritten_wq;
1251
1252         /* timer for periodic error stats printing */
1253         struct timer_list s_err_report;
1254
1255         /* Lazy inode table initialization info */
1256         struct ext4_li_request *s_li_request;
1257         /* Wait multiplier for lazy initialization thread */
1258         unsigned int s_li_wait_mult;
1259
1260         /* Kernel thread for multiple mount protection */
1261         struct task_struct *s_mmp_tsk;
1262
1263         /* record the last minlen when FITRIM is called. */
1264         atomic_t s_last_trim_minblks;
1265 };
1266
1267 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1268 {
1269         return sb->s_fs_info;
1270 }
1271 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1272 {
1273         return container_of(inode, struct ext4_inode_info, vfs_inode);
1274 }
1275
1276 static inline struct timespec ext4_current_time(struct inode *inode)
1277 {
1278         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1279                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1280 }
1281
1282 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1283 {
1284         return ino == EXT4_ROOT_INO ||
1285                 ino == EXT4_JOURNAL_INO ||
1286                 ino == EXT4_RESIZE_INO ||
1287                 (ino >= EXT4_FIRST_INO(sb) &&
1288                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1289 }
1290
1291 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1292                                               struct ext4_io_end *io_end)
1293 {
1294         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1295                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1296                 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
1297         }
1298 }
1299
1300 /*
1301  * Inode dynamic state flags
1302  */
1303 enum {
1304         EXT4_STATE_JDATA,               /* journaled data exists */
1305         EXT4_STATE_NEW,                 /* inode is newly created */
1306         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1307         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1308         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1309         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1310         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1311         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1312         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1313 };
1314
1315 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1316 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1317 {                                                                       \
1318         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1319 }                                                                       \
1320 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1321 {                                                                       \
1322         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1323 }                                                                       \
1324 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1325 {                                                                       \
1326         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1327 }
1328
1329 EXT4_INODE_BIT_FNS(flag, flags, 0)
1330 #if (BITS_PER_LONG < 64)
1331 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1332
1333 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1334 {
1335         (ei)->i_state_flags = 0;
1336 }
1337 #else
1338 EXT4_INODE_BIT_FNS(state, flags, 32)
1339
1340 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1341 {
1342         /* We depend on the fact that callers will set i_flags */
1343 }
1344 #endif
1345 #else
1346 /* Assume that user mode programs are passing in an ext4fs superblock, not
1347  * a kernel struct super_block.  This will allow us to call the feature-test
1348  * macros from user land. */
1349 #define EXT4_SB(sb)     (sb)
1350 #endif
1351
1352 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1353
1354 /*
1355  * Codes for operating systems
1356  */
1357 #define EXT4_OS_LINUX           0
1358 #define EXT4_OS_HURD            1
1359 #define EXT4_OS_MASIX           2
1360 #define EXT4_OS_FREEBSD         3
1361 #define EXT4_OS_LITES           4
1362
1363 /*
1364  * Revision levels
1365  */
1366 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1367 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1368
1369 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1370 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1371
1372 #define EXT4_GOOD_OLD_INODE_SIZE 128
1373
1374 /*
1375  * Feature set definitions
1376  */
1377
1378 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1379         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1380 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1381         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1382 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1383         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1384 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1385         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1386 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1387         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1388 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1389         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1390 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1391         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1392 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1393         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1394 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1395         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1396
1397 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1398 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1399 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1400 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1401 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1402 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1403
1404 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1405 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1406 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1407 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1408 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1409 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1410 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1411 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1412 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1413 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1414
1415 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1416 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1417 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1418 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1419 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1420 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1421 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1422 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1423 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1424 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1425 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1426 #define EXT4_FEATURE_INCOMPAT_INLINEDATA        0x2000 /* data in inode */
1427 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1428
1429 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1430 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1431                                          EXT4_FEATURE_INCOMPAT_META_BG)
1432 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1433                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1434                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1435
1436 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1437 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1438                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1439                                          EXT4_FEATURE_INCOMPAT_META_BG)
1440 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1441                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1442                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1443
1444 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1445 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1446                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1447                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1448                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1449                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1450                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1451                                          EXT4_FEATURE_INCOMPAT_MMP)
1452 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1453                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1454                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1455                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1456                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1457                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1458                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1459                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC)
1460
1461 /*
1462  * Default values for user and/or group using reserved blocks
1463  */
1464 #define EXT4_DEF_RESUID         0
1465 #define EXT4_DEF_RESGID         0
1466
1467 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1468
1469 /*
1470  * Default mount options
1471  */
1472 #define EXT4_DEFM_DEBUG         0x0001
1473 #define EXT4_DEFM_BSDGROUPS     0x0002
1474 #define EXT4_DEFM_XATTR_USER    0x0004
1475 #define EXT4_DEFM_ACL           0x0008
1476 #define EXT4_DEFM_UID16         0x0010
1477 #define EXT4_DEFM_JMODE         0x0060
1478 #define EXT4_DEFM_JMODE_DATA    0x0020
1479 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1480 #define EXT4_DEFM_JMODE_WBACK   0x0060
1481 #define EXT4_DEFM_NOBARRIER     0x0100
1482 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1483 #define EXT4_DEFM_DISCARD       0x0400
1484 #define EXT4_DEFM_NODELALLOC    0x0800
1485
1486 /*
1487  * Default journal batch times
1488  */
1489 #define EXT4_DEF_MIN_BATCH_TIME 0
1490 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1491
1492 /*
1493  * Minimum number of groups in a flexgroup before we separate out
1494  * directories into the first block group of a flexgroup
1495  */
1496 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1497
1498 /*
1499  * Structure of a directory entry
1500  */
1501 #define EXT4_NAME_LEN 255
1502
1503 struct ext4_dir_entry {
1504         __le32  inode;                  /* Inode number */
1505         __le16  rec_len;                /* Directory entry length */
1506         __le16  name_len;               /* Name length */
1507         char    name[EXT4_NAME_LEN];    /* File name */
1508 };
1509
1510 /*
1511  * The new version of the directory entry.  Since EXT4 structures are
1512  * stored in intel byte order, and the name_len field could never be
1513  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1514  * file_type field.
1515  */
1516 struct ext4_dir_entry_2 {
1517         __le32  inode;                  /* Inode number */
1518         __le16  rec_len;                /* Directory entry length */
1519         __u8    name_len;               /* Name length */
1520         __u8    file_type;
1521         char    name[EXT4_NAME_LEN];    /* File name */
1522 };
1523
1524 /*
1525  * Ext4 directory file types.  Only the low 3 bits are used.  The
1526  * other bits are reserved for now.
1527  */
1528 #define EXT4_FT_UNKNOWN         0
1529 #define EXT4_FT_REG_FILE        1
1530 #define EXT4_FT_DIR             2
1531 #define EXT4_FT_CHRDEV          3
1532 #define EXT4_FT_BLKDEV          4
1533 #define EXT4_FT_FIFO            5
1534 #define EXT4_FT_SOCK            6
1535 #define EXT4_FT_SYMLINK         7
1536
1537 #define EXT4_FT_MAX             8
1538
1539 /*
1540  * EXT4_DIR_PAD defines the directory entries boundaries
1541  *
1542  * NOTE: It must be a multiple of 4
1543  */
1544 #define EXT4_DIR_PAD                    4
1545 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1546 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1547                                          ~EXT4_DIR_ROUND)
1548 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1549
1550 /*
1551  * If we ever get support for fs block sizes > page_size, we'll need
1552  * to remove the #if statements in the next two functions...
1553  */
1554 static inline unsigned int
1555 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1556 {
1557         unsigned len = le16_to_cpu(dlen);
1558
1559 #if (PAGE_CACHE_SIZE >= 65536)
1560         if (len == EXT4_MAX_REC_LEN || len == 0)
1561                 return blocksize;
1562         return (len & 65532) | ((len & 3) << 16);
1563 #else
1564         return len;
1565 #endif
1566 }
1567
1568 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1569 {
1570         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1571                 BUG();
1572 #if (PAGE_CACHE_SIZE >= 65536)
1573         if (len < 65536)
1574                 return cpu_to_le16(len);
1575         if (len == blocksize) {
1576                 if (blocksize == 65536)
1577                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1578                 else
1579                         return cpu_to_le16(0);
1580         }
1581         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1582 #else
1583         return cpu_to_le16(len);
1584 #endif
1585 }
1586
1587 /*
1588  * Hash Tree Directory indexing
1589  * (c) Daniel Phillips, 2001
1590  */
1591
1592 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1593                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1594                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1595 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1596 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1597
1598 /* Legal values for the dx_root hash_version field: */
1599
1600 #define DX_HASH_LEGACY          0
1601 #define DX_HASH_HALF_MD4        1
1602 #define DX_HASH_TEA             2
1603 #define DX_HASH_LEGACY_UNSIGNED 3
1604 #define DX_HASH_HALF_MD4_UNSIGNED       4
1605 #define DX_HASH_TEA_UNSIGNED            5
1606
1607 #ifdef __KERNEL__
1608
1609 /* hash info structure used by the directory hash */
1610 struct dx_hash_info
1611 {
1612         u32             hash;
1613         u32             minor_hash;
1614         int             hash_version;
1615         u32             *seed;
1616 };
1617
1618 #define EXT4_HTREE_EOF  0x7fffffff
1619
1620 /*
1621  * Control parameters used by ext4_htree_next_block
1622  */
1623 #define HASH_NB_ALWAYS          1
1624
1625
1626 /*
1627  * Describe an inode's exact location on disk and in memory
1628  */
1629 struct ext4_iloc
1630 {
1631         struct buffer_head *bh;
1632         unsigned long offset;
1633         ext4_group_t block_group;
1634 };
1635
1636 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1637 {
1638         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1639 }
1640
1641 /*
1642  * This structure is stuffed into the struct file's private_data field
1643  * for directories.  It is where we put information so that we can do
1644  * readdir operations in hash tree order.
1645  */
1646 struct dir_private_info {
1647         struct rb_root  root;
1648         struct rb_node  *curr_node;
1649         struct fname    *extra_fname;
1650         loff_t          last_pos;
1651         __u32           curr_hash;
1652         __u32           curr_minor_hash;
1653         __u32           next_hash;
1654 };
1655
1656 /* calculate the first block number of the group */
1657 static inline ext4_fsblk_t
1658 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1659 {
1660         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1661                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1662 }
1663
1664 /*
1665  * Special error return code only used by dx_probe() and its callers.
1666  */
1667 #define ERR_BAD_DX_DIR  -75000
1668
1669 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1670                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1671
1672 /*
1673  * Timeout and state flag for lazy initialization inode thread.
1674  */
1675 #define EXT4_DEF_LI_WAIT_MULT                   10
1676 #define EXT4_DEF_LI_MAX_START_DELAY             5
1677 #define EXT4_LAZYINIT_QUIT                      0x0001
1678 #define EXT4_LAZYINIT_RUNNING                   0x0002
1679
1680 /*
1681  * Lazy inode table initialization info
1682  */
1683 struct ext4_lazy_init {
1684         unsigned long           li_state;
1685         struct list_head        li_request_list;
1686         struct mutex            li_list_mtx;
1687 };
1688
1689 struct ext4_li_request {
1690         struct super_block      *lr_super;
1691         struct ext4_sb_info     *lr_sbi;
1692         ext4_group_t            lr_next_group;
1693         struct list_head        lr_request;
1694         unsigned long           lr_next_sched;
1695         unsigned long           lr_timeout;
1696 };
1697
1698 struct ext4_features {
1699         struct kobject f_kobj;
1700         struct completion f_kobj_unregister;
1701 };
1702
1703 /*
1704  * This structure will be used for multiple mount protection. It will be
1705  * written into the block number saved in the s_mmp_block field in the
1706  * superblock. Programs that check MMP should assume that if
1707  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1708  * to use the filesystem, regardless of how old the timestamp is.
1709  */
1710 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1711 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1712 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1713 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1714
1715 struct mmp_struct {
1716         __le32  mmp_magic;              /* Magic number for MMP */
1717         __le32  mmp_seq;                /* Sequence no. updated periodically */
1718
1719         /*
1720          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1721          * purposes and do not affect the correctness of the algorithm
1722          */
1723         __le64  mmp_time;               /* Time last updated */
1724         char    mmp_nodename[64];       /* Node which last updated MMP block */
1725         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1726
1727         /*
1728          * mmp_check_interval is used to verify if the MMP block has been
1729          * updated on the block device. The value is updated based on the
1730          * maximum time to write the MMP block during an update cycle.
1731          */
1732         __le16  mmp_check_interval;
1733
1734         __le16  mmp_pad1;
1735         __le32  mmp_pad2[227];
1736 };
1737
1738 /* arguments passed to the mmp thread */
1739 struct mmpd_data {
1740         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1741         struct super_block *sb;  /* super block of the fs */
1742 };
1743
1744 /*
1745  * Check interval multiplier
1746  * The MMP block is written every update interval and initially checked every
1747  * update interval x the multiplier (the value is then adapted based on the
1748  * write latency). The reason is that writes can be delayed under load and we
1749  * don't want readers to incorrectly assume that the filesystem is no longer
1750  * in use.
1751  */
1752 #define EXT4_MMP_CHECK_MULT             2UL
1753
1754 /*
1755  * Minimum interval for MMP checking in seconds.
1756  */
1757 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1758
1759 /*
1760  * Maximum interval for MMP checking in seconds.
1761  */
1762 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1763
1764 /*
1765  * Function prototypes
1766  */
1767
1768 /*
1769  * Ok, these declarations are also in <linux/kernel.h> but none of the
1770  * ext4 source programs needs to include it so they are duplicated here.
1771  */
1772 # define NORET_TYPE     /**/
1773 # define ATTRIB_NORET   __attribute__((noreturn))
1774 # define NORET_AND      noreturn,
1775
1776 /* bitmap.c */
1777 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1778
1779 /* balloc.c */
1780 extern unsigned int ext4_block_group(struct super_block *sb,
1781                         ext4_fsblk_t blocknr);
1782 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1783                         ext4_fsblk_t blocknr);
1784 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1785 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1786                         ext4_group_t group);
1787 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1788                                          ext4_fsblk_t goal,
1789                                          unsigned int flags,
1790                                          unsigned long *count,
1791                                          int *errp);
1792 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1793                                     s64 nclusters, unsigned int flags);
1794 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1795 extern void ext4_check_blocks_bitmap(struct super_block *);
1796 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1797                                                     ext4_group_t block_group,
1798                                                     struct buffer_head ** bh);
1799 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1800 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1801                                       ext4_group_t block_group);
1802 extern void ext4_init_block_bitmap(struct super_block *sb,
1803                                    struct buffer_head *bh,
1804                                    ext4_group_t group,
1805                                    struct ext4_group_desc *desc);
1806 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1807                                               ext4_group_t block_group,
1808                                               struct ext4_group_desc *gdp);
1809 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1810                                            ext4_group_t block_group,
1811                                            struct ext4_group_desc *gdp);
1812 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1813
1814 /* dir.c */
1815 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1816                                   struct file *,
1817                                   struct ext4_dir_entry_2 *,
1818                                   struct buffer_head *, unsigned int);
1819 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1820         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1821                                         (de), (bh), (offset)))
1822 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1823                                     __u32 minor_hash,
1824                                     struct ext4_dir_entry_2 *dirent);
1825 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1826
1827 /* fsync.c */
1828 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1829 extern int ext4_flush_completed_IO(struct inode *);
1830
1831 /* hash.c */
1832 extern int ext4fs_dirhash(const char *name, int len, struct
1833                           dx_hash_info *hinfo);
1834
1835 /* ialloc.c */
1836 extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1837                                     const struct qstr *qstr, __u32 goal,
1838                                     uid_t *owner);
1839 extern void ext4_free_inode(handle_t *, struct inode *);
1840 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1841 extern unsigned long ext4_count_free_inodes(struct super_block *);
1842 extern unsigned long ext4_count_dirs(struct super_block *);
1843 extern void ext4_check_inodes_bitmap(struct super_block *);
1844 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1845 extern int ext4_init_inode_table(struct super_block *sb,
1846                                  ext4_group_t group, int barrier);
1847
1848 /* mballoc.c */
1849 extern long ext4_mb_stats;
1850 extern long ext4_mb_max_to_scan;
1851 extern int ext4_mb_init(struct super_block *, int);
1852 extern int ext4_mb_release(struct super_block *);
1853 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1854                                 struct ext4_allocation_request *, int *);
1855 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1856 extern void ext4_discard_preallocations(struct inode *);
1857 extern int __init ext4_init_mballoc(void);
1858 extern void ext4_exit_mballoc(void);
1859 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1860                              struct buffer_head *bh, ext4_fsblk_t block,
1861                              unsigned long count, int flags);
1862 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1863                 ext4_group_t i, struct ext4_group_desc *desc);
1864 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1865                                 ext4_fsblk_t block, unsigned long count);
1866 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1867
1868 /* inode.c */
1869 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1870                                                 ext4_lblk_t, int, int *);
1871 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1872                                                 ext4_lblk_t, int, int *);
1873 int ext4_get_block(struct inode *inode, sector_t iblock,
1874                                 struct buffer_head *bh_result, int create);
1875
1876 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1877 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1878 extern int  ext4_setattr(struct dentry *, struct iattr *);
1879 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1880                                 struct kstat *stat);
1881 extern void ext4_evict_inode(struct inode *);
1882 extern void ext4_clear_inode(struct inode *);
1883 extern int  ext4_sync_inode(handle_t *, struct inode *);
1884 extern void ext4_dirty_inode(struct inode *, int);
1885 extern int ext4_change_inode_journal_flag(struct inode *, int);
1886 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1887 extern int ext4_can_truncate(struct inode *inode);
1888 extern void ext4_truncate(struct inode *);
1889 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1890 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1891 extern void ext4_set_inode_flags(struct inode *);
1892 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1893 extern int ext4_alloc_da_blocks(struct inode *inode);
1894 extern void ext4_set_aops(struct inode *inode);
1895 extern int ext4_writepage_trans_blocks(struct inode *);
1896 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1897 extern int ext4_discard_partial_page_buffers(handle_t *handle,
1898                 struct address_space *mapping, loff_t from,
1899                 loff_t length, int flags);
1900 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1901 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1902 extern void ext4_da_update_reserve_space(struct inode *inode,
1903                                         int used, int quota_claim);
1904
1905 /* indirect.c */
1906 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
1907                                 struct ext4_map_blocks *map, int flags);
1908 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
1909                                 const struct iovec *iov, loff_t offset,
1910                                 unsigned long nr_segs);
1911 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
1912 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
1913 extern void ext4_ind_truncate(struct inode *inode);
1914
1915 /* ioctl.c */
1916 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1917 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1918
1919 /* migrate.c */
1920 extern int ext4_ext_migrate(struct inode *);
1921
1922 /* namei.c */
1923 extern int ext4_orphan_add(handle_t *, struct inode *);
1924 extern int ext4_orphan_del(handle_t *, struct inode *);
1925 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1926                                 __u32 start_minor_hash, __u32 *next_hash);
1927
1928 /* resize.c */
1929 extern int ext4_group_add(struct super_block *sb,
1930                                 struct ext4_new_group_data *input);
1931 extern int ext4_group_extend(struct super_block *sb,
1932                                 struct ext4_super_block *es,
1933                                 ext4_fsblk_t n_blocks_count);
1934 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
1935
1936 /* super.c */
1937 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
1938 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
1939 extern void ext4_kvfree(void *ptr);
1940 extern __printf(4, 5)
1941 void __ext4_error(struct super_block *, const char *, unsigned int,
1942                   const char *, ...);
1943 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
1944                                                      __LINE__, ## message)
1945 extern __printf(5, 6)
1946 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
1947                       const char *, ...);
1948 extern __printf(5, 6)
1949 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
1950                      const char *, ...);
1951 extern void __ext4_std_error(struct super_block *, const char *,
1952                              unsigned int, int);
1953 extern __printf(4, 5)
1954 void __ext4_abort(struct super_block *, const char *, unsigned int,
1955                   const char *, ...);
1956 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
1957                                                        __LINE__, ## message)
1958 extern __printf(4, 5)
1959 void __ext4_warning(struct super_block *, const char *, unsigned int,
1960                     const char *, ...);
1961 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
1962                                                        __LINE__, ## message)
1963 extern __printf(3, 4)
1964 void ext4_msg(struct super_block *, const char *, const char *, ...);
1965 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
1966                            const char *, unsigned int, const char *);
1967 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
1968                                                        __LINE__, msg)
1969 extern __printf(7, 8)
1970 void __ext4_grp_locked_error(const char *, unsigned int,
1971                              struct super_block *, ext4_group_t,
1972                              unsigned long, ext4_fsblk_t,
1973                              const char *, ...);
1974 #define ext4_grp_locked_error(sb, grp, message...) \
1975         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1976 extern void ext4_update_dynamic_rev(struct super_block *sb);
1977 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1978                                         __u32 compat);
1979 extern int ext4_update_rocompat_feature(handle_t *handle,
1980                                         struct super_block *sb, __u32 rocompat);
1981 extern int ext4_update_incompat_feature(handle_t *handle,
1982                                         struct super_block *sb, __u32 incompat);
1983 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1984                                       struct ext4_group_desc *bg);
1985 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1986                                       struct ext4_group_desc *bg);
1987 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1988                                      struct ext4_group_desc *bg);
1989 extern __u32 ext4_free_group_clusters(struct super_block *sb,
1990                                       struct ext4_group_desc *bg);
1991 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1992                                  struct ext4_group_desc *bg);
1993 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1994                                 struct ext4_group_desc *bg);
1995 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1996                                    struct ext4_group_desc *bg);
1997 extern void ext4_block_bitmap_set(struct super_block *sb,
1998                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1999 extern void ext4_inode_bitmap_set(struct super_block *sb,
2000                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2001 extern void ext4_inode_table_set(struct super_block *sb,
2002                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2003 extern void ext4_free_group_clusters_set(struct super_block *sb,
2004                                          struct ext4_group_desc *bg,
2005                                          __u32 count);
2006 extern void ext4_free_inodes_set(struct super_block *sb,
2007                                 struct ext4_group_desc *bg, __u32 count);
2008 extern void ext4_used_dirs_set(struct super_block *sb,
2009                                 struct ext4_group_desc *bg, __u32 count);
2010 extern void ext4_itable_unused_set(struct super_block *sb,
2011                                    struct ext4_group_desc *bg, __u32 count);
2012 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
2013                                    struct ext4_group_desc *gdp);
2014 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
2015                                        struct ext4_group_desc *gdp);
2016
2017 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2018 {
2019         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2020                 le32_to_cpu(es->s_blocks_count_lo);
2021 }
2022
2023 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2024 {
2025         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2026                 le32_to_cpu(es->s_r_blocks_count_lo);
2027 }
2028
2029 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2030 {
2031         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2032                 le32_to_cpu(es->s_free_blocks_count_lo);
2033 }
2034
2035 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2036                                          ext4_fsblk_t blk)
2037 {
2038         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2039         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2040 }
2041
2042 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2043                                               ext4_fsblk_t blk)
2044 {
2045         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2046         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2047 }
2048
2049 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2050                                            ext4_fsblk_t blk)
2051 {
2052         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2053         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2054 }
2055
2056 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2057 {
2058         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2059                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2060                         le32_to_cpu(raw_inode->i_size_lo);
2061         else
2062                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2063 }
2064
2065 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2066 {
2067         raw_inode->i_size_lo = cpu_to_le32(i_size);
2068         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2069 }
2070
2071 static inline
2072 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2073                                             ext4_group_t group)
2074 {
2075          struct ext4_group_info ***grp_info;
2076          long indexv, indexh;
2077          grp_info = EXT4_SB(sb)->s_group_info;
2078          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2079          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2080          return grp_info[indexv][indexh];
2081 }
2082
2083 /*
2084  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2085  * the locking protocol documented in the comments of ext4_group_add()
2086  * in resize.c
2087  */
2088 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2089 {
2090         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2091
2092         smp_rmb();
2093         return ngroups;
2094 }
2095
2096 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2097                                              ext4_group_t block_group)
2098 {
2099         return block_group >> sbi->s_log_groups_per_flex;
2100 }
2101
2102 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2103 {
2104         return 1 << sbi->s_log_groups_per_flex;
2105 }
2106
2107 #define ext4_std_error(sb, errno)                               \
2108 do {                                                            \
2109         if ((errno))                                            \
2110                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2111 } while (0)
2112
2113 #ifdef CONFIG_SMP
2114 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2115  * counters. So we need to make sure we have free clusters more
2116  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2117  */
2118 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2119 #else
2120 #define EXT4_FREECLUSTERS_WATERMARK 0
2121 #endif
2122
2123 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2124 {
2125         /*
2126          * XXX: replace with spinlock if seen contended -bzzz
2127          */
2128         down_write(&EXT4_I(inode)->i_data_sem);
2129         if (newsize > EXT4_I(inode)->i_disksize)
2130                 EXT4_I(inode)->i_disksize = newsize;
2131         up_write(&EXT4_I(inode)->i_data_sem);
2132         return ;
2133 }
2134
2135 struct ext4_group_info {
2136         unsigned long   bb_state;
2137         struct rb_root  bb_free_root;
2138         ext4_grpblk_t   bb_first_free;  /* first free block */
2139         ext4_grpblk_t   bb_free;        /* total free blocks */
2140         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2141         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2142         struct          list_head bb_prealloc_list;
2143 #ifdef DOUBLE_CHECK
2144         void            *bb_bitmap;
2145 #endif
2146         struct rw_semaphore alloc_sem;
2147         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2148                                          * regions, index is order.
2149                                          * bb_counters[3] = 5 means
2150                                          * 5 free 8-block regions. */
2151 };
2152
2153 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2154 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2155
2156 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2157         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2158
2159 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2160         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2161 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2162         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2163 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2164         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2165
2166 #define EXT4_MAX_CONTENTION             8
2167 #define EXT4_CONTENTION_THRESHOLD       2
2168
2169 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2170                                               ext4_group_t group)
2171 {
2172         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2173 }
2174
2175 /*
2176  * Returns true if the filesystem is busy enough that attempts to
2177  * access the block group locks has run into contention.
2178  */
2179 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2180 {
2181         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2182 }
2183
2184 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2185 {
2186         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2187         if (spin_trylock(lock))
2188                 /*
2189                  * We're able to grab the lock right away, so drop the
2190                  * lock contention counter.
2191                  */
2192                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2193         else {
2194                 /*
2195                  * The lock is busy, so bump the contention counter,
2196                  * and then wait on the spin lock.
2197                  */
2198                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2199                                   EXT4_MAX_CONTENTION);
2200                 spin_lock(lock);
2201         }
2202 }
2203
2204 static inline void ext4_unlock_group(struct super_block *sb,
2205                                         ext4_group_t group)
2206 {
2207         spin_unlock(ext4_group_lock_ptr(sb, group));
2208 }
2209
2210 static inline void ext4_mark_super_dirty(struct super_block *sb)
2211 {
2212         if (EXT4_SB(sb)->s_journal == NULL)
2213                 sb->s_dirt =1;
2214 }
2215
2216 /*
2217  * Block validity checking
2218  */
2219 #define ext4_check_indirect_blockref(inode, bh)                         \
2220         ext4_check_blockref(__func__, __LINE__, inode,                  \
2221                             (__le32 *)(bh)->b_data,                     \
2222                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2223
2224 #define ext4_ind_check_inode(inode)                                     \
2225         ext4_check_blockref(__func__, __LINE__, inode,                  \
2226                             EXT4_I(inode)->i_data,                      \
2227                             EXT4_NDIR_BLOCKS)
2228
2229 /*
2230  * Inodes and files operations
2231  */
2232
2233 /* dir.c */
2234 extern const struct file_operations ext4_dir_operations;
2235
2236 /* file.c */
2237 extern const struct inode_operations ext4_file_inode_operations;
2238 extern const struct file_operations ext4_file_operations;
2239 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2240
2241 /* namei.c */
2242 extern const struct inode_operations ext4_dir_inode_operations;
2243 extern const struct inode_operations ext4_special_inode_operations;
2244 extern struct dentry *ext4_get_parent(struct dentry *child);
2245
2246 /* symlink.c */
2247 extern const struct inode_operations ext4_symlink_inode_operations;
2248 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2249
2250 /* block_validity */
2251 extern void ext4_release_system_zone(struct super_block *sb);
2252 extern int ext4_setup_system_zone(struct super_block *sb);
2253 extern int __init ext4_init_system_zone(void);
2254 extern void ext4_exit_system_zone(void);
2255 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2256                                  ext4_fsblk_t start_blk,
2257                                  unsigned int count);
2258 extern int ext4_check_blockref(const char *, unsigned int,
2259                                struct inode *, __le32 *, unsigned int);
2260
2261 /* extents.c */
2262 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2263 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2264 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2265                                        int chunk);
2266 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2267                                struct ext4_map_blocks *map, int flags);
2268 extern void ext4_ext_truncate(struct inode *);
2269 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2270                                 loff_t length);
2271 extern void ext4_ext_init(struct super_block *);
2272 extern void ext4_ext_release(struct super_block *);
2273 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2274                           loff_t len);
2275 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2276                           ssize_t len);
2277 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2278                            struct ext4_map_blocks *map, int flags);
2279 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2280                         __u64 start, __u64 len);
2281 /* move_extent.c */
2282 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2283                              __u64 start_orig, __u64 start_donor,
2284                              __u64 len, __u64 *moved_len);
2285
2286 /* page-io.c */
2287 extern int __init ext4_init_pageio(void);
2288 extern void ext4_exit_pageio(void);
2289 extern void ext4_ioend_wait(struct inode *);
2290 extern void ext4_free_io_end(ext4_io_end_t *io);
2291 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2292 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2293 extern void ext4_io_submit(struct ext4_io_submit *io);
2294 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2295                                struct page *page,
2296                                int len,
2297                                struct writeback_control *wbc);
2298
2299 /* mmp.c */
2300 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2301
2302 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2303 enum ext4_state_bits {
2304         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2305           = BH_JBDPrivateStart,
2306         BH_AllocFromCluster,    /* allocated blocks were part of already
2307                                  * allocated cluster. Note that this flag will
2308                                  * never, ever appear in a buffer_head's state
2309                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2310                                  * this is used. */
2311         BH_Da_Mapped,   /* Delayed allocated block that now has a mapping. This
2312                          * flag is set when ext4_map_blocks is called on a
2313                          * delayed allocated block to get its real mapping. */
2314 };
2315
2316 BUFFER_FNS(Uninit, uninit)
2317 TAS_BUFFER_FNS(Uninit, uninit)
2318 BUFFER_FNS(Da_Mapped, da_mapped)
2319
2320 /*
2321  * Add new method to test wether block and inode bitmaps are properly
2322  * initialized. With uninit_bg reading the block from disk is not enough
2323  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2324  */
2325 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2326
2327 static inline int bitmap_uptodate(struct buffer_head *bh)
2328 {
2329         return (buffer_uptodate(bh) &&
2330                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2331 }
2332 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2333 {
2334         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2335 }
2336
2337 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2338
2339 /* For ioend & aio unwritten conversion wait queues */
2340 #define EXT4_WQ_HASH_SZ         37
2341 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2342                                             EXT4_WQ_HASH_SZ])
2343 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2344                                              EXT4_WQ_HASH_SZ])
2345 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2346 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2347
2348 #define EXT4_RESIZING   0
2349 extern int ext4_resize_begin(struct super_block *sb);
2350 extern void ext4_resize_end(struct super_block *sb);
2351
2352 #endif  /* __KERNEL__ */
2353
2354 #include "ext4_extents.h"
2355
2356 #endif  /* _EXT4_H */