Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6] / 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 "ext4_i.h"
25
26 /*
27  * The fourth extended filesystem constants/structures
28  */
29
30 /*
31  * Define EXT4FS_DEBUG to produce debug messages
32  */
33 #undef EXT4FS_DEBUG
34
35 /*
36  * Debug code
37  */
38 #ifdef EXT4FS_DEBUG
39 #define ext4_debug(f, a...)                                             \
40         do {                                                            \
41                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
42                         __FILE__, __LINE__, __func__);                  \
43                 printk(KERN_DEBUG f, ## a);                             \
44         } while (0)
45 #else
46 #define ext4_debug(f, a...)     do {} while (0)
47 #endif
48
49 /* prefer goal again. length */
50 #define EXT4_MB_HINT_MERGE              1
51 /* blocks already reserved */
52 #define EXT4_MB_HINT_RESERVED           2
53 /* metadata is being allocated */
54 #define EXT4_MB_HINT_METADATA           4
55 /* first blocks in the file */
56 #define EXT4_MB_HINT_FIRST              8
57 /* search for the best chunk */
58 #define EXT4_MB_HINT_BEST               16
59 /* data is being allocated */
60 #define EXT4_MB_HINT_DATA               32
61 /* don't preallocate (for tails) */
62 #define EXT4_MB_HINT_NOPREALLOC         64
63 /* allocate for locality group */
64 #define EXT4_MB_HINT_GROUP_ALLOC        128
65 /* allocate goal blocks or none */
66 #define EXT4_MB_HINT_GOAL_ONLY          256
67 /* goal is meaningful */
68 #define EXT4_MB_HINT_TRY_GOAL           512
69 /* blocks already pre-reserved by delayed allocation */
70 #define EXT4_MB_DELALLOC_RESERVED      1024
71
72
73 struct ext4_allocation_request {
74         /* target inode for block we're allocating */
75         struct inode *inode;
76         /* logical block in target inode */
77         ext4_lblk_t logical;
78         /* phys. target (a hint) */
79         ext4_fsblk_t goal;
80         /* the closest logical allocated block to the left */
81         ext4_lblk_t lleft;
82         /* phys. block for ^^^ */
83         ext4_fsblk_t pleft;
84         /* the closest logical allocated block to the right */
85         ext4_lblk_t lright;
86         /* phys. block for ^^^ */
87         ext4_fsblk_t pright;
88         /* how many blocks we want to allocate */
89         unsigned int len;
90         /* flags. see above EXT4_MB_HINT_* */
91         unsigned int flags;
92 };
93
94 /*
95  * Special inodes numbers
96  */
97 #define EXT4_BAD_INO             1      /* Bad blocks inode */
98 #define EXT4_ROOT_INO            2      /* Root inode */
99 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
100 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
101 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
102 #define EXT4_JOURNAL_INO         8      /* Journal inode */
103
104 /* First non-reserved inode for old ext4 filesystems */
105 #define EXT4_GOOD_OLD_FIRST_INO 11
106
107 /*
108  * Maximal count of links to a file
109  */
110 #define EXT4_LINK_MAX           65000
111
112 /*
113  * Macro-instructions used to manage several block sizes
114  */
115 #define EXT4_MIN_BLOCK_SIZE             1024
116 #define EXT4_MAX_BLOCK_SIZE             65536
117 #define EXT4_MIN_BLOCK_LOG_SIZE         10
118 #ifdef __KERNEL__
119 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
120 #else
121 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
122 #endif
123 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
124 #ifdef __KERNEL__
125 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
126 #else
127 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
128 #endif
129 #ifdef __KERNEL__
130 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
131 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
132 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
133 #else
134 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
135                                  EXT4_GOOD_OLD_INODE_SIZE : \
136                                  (s)->s_inode_size)
137 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
138                                  EXT4_GOOD_OLD_FIRST_INO : \
139                                  (s)->s_first_ino)
140 #endif
141 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
142
143 /*
144  * Structure of a blocks group descriptor
145  */
146 struct ext4_group_desc
147 {
148         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
149         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
150         __le32  bg_inode_table_lo;      /* Inodes table block */
151         __le16  bg_free_blocks_count_lo;/* Free blocks count */
152         __le16  bg_free_inodes_count_lo;/* Free inodes count */
153         __le16  bg_used_dirs_count_lo;  /* Directories count */
154         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
155         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
156         __le16  bg_itable_unused_lo;    /* Unused inodes count */
157         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
158         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
159         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
160         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
161         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
162         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
163         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
164         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
165         __u32   bg_reserved2[3];
166 };
167
168 /*
169  * Structure of a flex block group info
170  */
171
172 struct flex_groups {
173         atomic_t free_inodes;
174         atomic_t free_blocks;
175         atomic_t used_dirs;
176 };
177
178 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
179 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
180 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
181
182 #ifdef __KERNEL__
183 #include "ext4_sb.h"
184 #endif
185 /*
186  * Macro-instructions used to manage group descriptors
187  */
188 #define EXT4_MIN_DESC_SIZE              32
189 #define EXT4_MIN_DESC_SIZE_64BIT        64
190 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
191 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
192 #ifdef __KERNEL__
193 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
194 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
195 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
196 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
197 #else
198 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
199 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
200 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
201 #endif
202
203 /*
204  * Constants relative to the data blocks
205  */
206 #define EXT4_NDIR_BLOCKS                12
207 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
208 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
209 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
210 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
211
212 /*
213  * Inode flags
214  */
215 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
216 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
217 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
218 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
219 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
220 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
221 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
222 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
223 /* Reserved for compression usage... */
224 #define EXT4_DIRTY_FL                   0x00000100
225 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
226 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
227 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
228 /* End compression flags --- maybe not all used */
229 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
230 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
231 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
232 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
233 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
234 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
235 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
236 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
237 #define EXT4_EXT_MIGRATE                0x00100000 /* Inode is migrating */
238 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
239
240 #define EXT4_FL_USER_VISIBLE            0x000BDFFF /* User visible flags */
241 #define EXT4_FL_USER_MODIFIABLE         0x000B80FF /* User modifiable flags */
242
243 /* Flags that should be inherited by new inodes from their parent. */
244 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
245                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
246                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
247                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
248                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
249
250 /* Flags that are appropriate for regular files (all but dir-specific ones). */
251 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
252
253 /* Flags that are appropriate for non-directories/regular files. */
254 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
255
256 /* Mask out flags that are inappropriate for the given type of inode. */
257 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
258 {
259         if (S_ISDIR(mode))
260                 return flags;
261         else if (S_ISREG(mode))
262                 return flags & EXT4_REG_FLMASK;
263         else
264                 return flags & EXT4_OTHER_FLMASK;
265 }
266
267 /*
268  * Inode dynamic state flags
269  */
270 #define EXT4_STATE_JDATA                0x00000001 /* journaled data exists */
271 #define EXT4_STATE_NEW                  0x00000002 /* inode is newly created */
272 #define EXT4_STATE_XATTR                0x00000004 /* has in-inode xattrs */
273 #define EXT4_STATE_NO_EXPAND            0x00000008 /* No space for expansion */
274 #define EXT4_STATE_DA_ALLOC_CLOSE       0x00000010 /* Alloc DA blks on close */
275
276 /* Used to pass group descriptor data when online resize is done */
277 struct ext4_new_group_input {
278         __u32 group;            /* Group number for this data */
279         __u64 block_bitmap;     /* Absolute block number of block bitmap */
280         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
281         __u64 inode_table;      /* Absolute block number of inode table start */
282         __u32 blocks_count;     /* Total number of blocks in this group */
283         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
284         __u16 unused;
285 };
286
287 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
288 struct ext4_new_group_data {
289         __u32 group;
290         __u64 block_bitmap;
291         __u64 inode_bitmap;
292         __u64 inode_table;
293         __u32 blocks_count;
294         __u16 reserved_blocks;
295         __u16 unused;
296         __u32 free_blocks_count;
297 };
298
299 /*
300  * Following is used by preallocation code to tell get_blocks() that we
301  * want uninitialzed extents.
302  */
303 #define EXT4_CREATE_UNINITIALIZED_EXT           2
304
305 /*
306  * ioctl commands
307  */
308 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
309 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
310 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
311 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
312 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
313 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
314 #ifdef CONFIG_JBD2_DEBUG
315 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
316 #endif
317 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
318 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
319 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
320 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
321 #define EXT4_IOC_MIGRATE                _IO('f', 9)
322  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
323  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
324 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
325
326 /*
327  * ioctl commands in 32 bit emulation
328  */
329 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
330 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
331 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
332 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
333 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
334 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
335 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
336 #ifdef CONFIG_JBD2_DEBUG
337 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
338 #endif
339 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
340 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
341
342
343 /*
344  *  Mount options
345  */
346 struct ext4_mount_options {
347         unsigned long s_mount_opt;
348         uid_t s_resuid;
349         gid_t s_resgid;
350         unsigned long s_commit_interval;
351         u32 s_min_batch_time, s_max_batch_time;
352 #ifdef CONFIG_QUOTA
353         int s_jquota_fmt;
354         char *s_qf_names[MAXQUOTAS];
355 #endif
356 };
357
358 /*
359  * Structure of an inode on the disk
360  */
361 struct ext4_inode {
362         __le16  i_mode;         /* File mode */
363         __le16  i_uid;          /* Low 16 bits of Owner Uid */
364         __le32  i_size_lo;      /* Size in bytes */
365         __le32  i_atime;        /* Access time */
366         __le32  i_ctime;        /* Inode Change time */
367         __le32  i_mtime;        /* Modification time */
368         __le32  i_dtime;        /* Deletion Time */
369         __le16  i_gid;          /* Low 16 bits of Group Id */
370         __le16  i_links_count;  /* Links count */
371         __le32  i_blocks_lo;    /* Blocks count */
372         __le32  i_flags;        /* File flags */
373         union {
374                 struct {
375                         __le32  l_i_version;
376                 } linux1;
377                 struct {
378                         __u32  h_i_translator;
379                 } hurd1;
380                 struct {
381                         __u32  m_i_reserved1;
382                 } masix1;
383         } osd1;                         /* OS dependent 1 */
384         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
385         __le32  i_generation;   /* File version (for NFS) */
386         __le32  i_file_acl_lo;  /* File ACL */
387         __le32  i_size_high;
388         __le32  i_obso_faddr;   /* Obsoleted fragment address */
389         union {
390                 struct {
391                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
392                         __le16  l_i_file_acl_high;
393                         __le16  l_i_uid_high;   /* these 2 fields */
394                         __le16  l_i_gid_high;   /* were reserved2[0] */
395                         __u32   l_i_reserved2;
396                 } linux2;
397                 struct {
398                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
399                         __u16   h_i_mode_high;
400                         __u16   h_i_uid_high;
401                         __u16   h_i_gid_high;
402                         __u32   h_i_author;
403                 } hurd2;
404                 struct {
405                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
406                         __le16  m_i_file_acl_high;
407                         __u32   m_i_reserved2[2];
408                 } masix2;
409         } osd2;                         /* OS dependent 2 */
410         __le16  i_extra_isize;
411         __le16  i_pad1;
412         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
413         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
414         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
415         __le32  i_crtime;       /* File Creation time */
416         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
417         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
418 };
419
420
421 #define EXT4_EPOCH_BITS 2
422 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
423 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
424
425 /*
426  * Extended fields will fit into an inode if the filesystem was formatted
427  * with large inodes (-I 256 or larger) and there are not currently any EAs
428  * consuming all of the available space. For new inodes we always reserve
429  * enough space for the kernel's known extended fields, but for inodes
430  * created with an old kernel this might not have been the case. None of
431  * the extended inode fields is critical for correct filesystem operation.
432  * This macro checks if a certain field fits in the inode. Note that
433  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
434  */
435 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
436         ((offsetof(typeof(*ext4_inode), field) +        \
437           sizeof((ext4_inode)->field))                  \
438         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
439             (einode)->i_extra_isize))                   \
440
441 static inline __le32 ext4_encode_extra_time(struct timespec *time)
442 {
443        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
444                            time->tv_sec >> 32 : 0) |
445                            ((time->tv_nsec << 2) & EXT4_NSEC_MASK));
446 }
447
448 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
449 {
450        if (sizeof(time->tv_sec) > 4)
451                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
452                                << 32;
453        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> 2;
454 }
455
456 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
457 do {                                                                           \
458         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
459         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
460                 (raw_inode)->xtime ## _extra =                                 \
461                                 ext4_encode_extra_time(&(inode)->xtime);       \
462 } while (0)
463
464 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
465 do {                                                                           \
466         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
467                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
468         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
469                 (raw_inode)->xtime ## _extra =                                 \
470                                 ext4_encode_extra_time(&(einode)->xtime);      \
471 } while (0)
472
473 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
474 do {                                                                           \
475         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
476         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
477                 ext4_decode_extra_time(&(inode)->xtime,                        \
478                                        raw_inode->xtime ## _extra);            \
479 } while (0)
480
481 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
482 do {                                                                           \
483         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
484                 (einode)->xtime.tv_sec =                                       \
485                         (signed)le32_to_cpu((raw_inode)->xtime);               \
486         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
487                 ext4_decode_extra_time(&(einode)->xtime,                       \
488                                        raw_inode->xtime ## _extra);            \
489 } while (0)
490
491 #define i_disk_version osd1.linux1.l_i_version
492
493 #if defined(__KERNEL__) || defined(__linux__)
494 #define i_reserved1     osd1.linux1.l_i_reserved1
495 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
496 #define i_blocks_high   osd2.linux2.l_i_blocks_high
497 #define i_uid_low       i_uid
498 #define i_gid_low       i_gid
499 #define i_uid_high      osd2.linux2.l_i_uid_high
500 #define i_gid_high      osd2.linux2.l_i_gid_high
501 #define i_reserved2     osd2.linux2.l_i_reserved2
502
503 #elif defined(__GNU__)
504
505 #define i_translator    osd1.hurd1.h_i_translator
506 #define i_uid_high      osd2.hurd2.h_i_uid_high
507 #define i_gid_high      osd2.hurd2.h_i_gid_high
508 #define i_author        osd2.hurd2.h_i_author
509
510 #elif defined(__masix__)
511
512 #define i_reserved1     osd1.masix1.m_i_reserved1
513 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
514 #define i_reserved2     osd2.masix2.m_i_reserved2
515
516 #endif /* defined(__KERNEL__) || defined(__linux__) */
517
518 /*
519  * File system states
520  */
521 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
522 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
523 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
524
525 /*
526  * Misc. filesystem flags
527  */
528 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
529 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
530 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
531
532 /*
533  * Mount flags
534  */
535 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
536 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
537 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
538 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
539 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
540 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
541 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
542 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
543 #define EXT4_MOUNT_ABORT                0x00200 /* Fatal error detected */
544 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
545 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
546 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
547 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
548 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
549 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
550 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
551 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
552 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
553 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
554 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
555 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
556 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
557 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
558 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
559 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
560 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
561 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
562 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
563
564 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
565 #ifndef _LINUX_EXT2_FS_H
566 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
567 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
568 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
569                                          EXT4_MOUNT_##opt)
570 #else
571 #define EXT2_MOUNT_NOLOAD               EXT4_MOUNT_NOLOAD
572 #define EXT2_MOUNT_ABORT                EXT4_MOUNT_ABORT
573 #define EXT2_MOUNT_DATA_FLAGS           EXT4_MOUNT_DATA_FLAGS
574 #endif
575
576 #define ext4_set_bit                    ext2_set_bit
577 #define ext4_set_bit_atomic             ext2_set_bit_atomic
578 #define ext4_clear_bit                  ext2_clear_bit
579 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
580 #define ext4_test_bit                   ext2_test_bit
581 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
582 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
583 #define ext4_find_next_bit              ext2_find_next_bit
584
585 /*
586  * Maximal mount counts between two filesystem checks
587  */
588 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
589 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
590
591 /*
592  * Behaviour when detecting errors
593  */
594 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
595 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
596 #define EXT4_ERRORS_PANIC               3       /* Panic */
597 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
598
599 /*
600  * Structure of the super block
601  */
602 struct ext4_super_block {
603 /*00*/  __le32  s_inodes_count;         /* Inodes count */
604         __le32  s_blocks_count_lo;      /* Blocks count */
605         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
606         __le32  s_free_blocks_count_lo; /* Free blocks count */
607 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
608         __le32  s_first_data_block;     /* First Data Block */
609         __le32  s_log_block_size;       /* Block size */
610         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
611 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
612         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
613         __le32  s_inodes_per_group;     /* # Inodes per group */
614         __le32  s_mtime;                /* Mount time */
615 /*30*/  __le32  s_wtime;                /* Write time */
616         __le16  s_mnt_count;            /* Mount count */
617         __le16  s_max_mnt_count;        /* Maximal mount count */
618         __le16  s_magic;                /* Magic signature */
619         __le16  s_state;                /* File system state */
620         __le16  s_errors;               /* Behaviour when detecting errors */
621         __le16  s_minor_rev_level;      /* minor revision level */
622 /*40*/  __le32  s_lastcheck;            /* time of last check */
623         __le32  s_checkinterval;        /* max. time between checks */
624         __le32  s_creator_os;           /* OS */
625         __le32  s_rev_level;            /* Revision level */
626 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
627         __le16  s_def_resgid;           /* Default gid for reserved blocks */
628         /*
629          * These fields are for EXT4_DYNAMIC_REV superblocks only.
630          *
631          * Note: the difference between the compatible feature set and
632          * the incompatible feature set is that if there is a bit set
633          * in the incompatible feature set that the kernel doesn't
634          * know about, it should refuse to mount the filesystem.
635          *
636          * e2fsck's requirements are more strict; if it doesn't know
637          * about a feature in either the compatible or incompatible
638          * feature set, it must abort and not try to meddle with
639          * things it doesn't understand...
640          */
641         __le32  s_first_ino;            /* First non-reserved inode */
642         __le16  s_inode_size;           /* size of inode structure */
643         __le16  s_block_group_nr;       /* block group # of this superblock */
644         __le32  s_feature_compat;       /* compatible feature set */
645 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
646         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
647 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
648 /*78*/  char    s_volume_name[16];      /* volume name */
649 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
650 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
651         /*
652          * Performance hints.  Directory preallocation should only
653          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
654          */
655         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
656         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
657         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
658         /*
659          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
660          */
661 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
662 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
663         __le32  s_journal_dev;          /* device number of journal file */
664         __le32  s_last_orphan;          /* start of list of inodes to delete */
665         __le32  s_hash_seed[4];         /* HTREE hash seed */
666         __u8    s_def_hash_version;     /* Default hash version to use */
667         __u8    s_reserved_char_pad;
668         __le16  s_desc_size;            /* size of group descriptor */
669 /*100*/ __le32  s_default_mount_opts;
670         __le32  s_first_meta_bg;        /* First metablock block group */
671         __le32  s_mkfs_time;            /* When the filesystem was created */
672         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
673         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
674 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
675         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
676         __le32  s_free_blocks_count_hi; /* Free blocks count */
677         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
678         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
679         __le32  s_flags;                /* Miscellaneous flags */
680         __le16  s_raid_stride;          /* RAID stride */
681         __le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
682         __le64  s_mmp_block;            /* Block for multi-mount protection */
683         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
684         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
685         __u8    s_reserved_char_pad2;
686         __le16  s_reserved_pad;
687         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
688         __u32   s_reserved[160];        /* Padding to the end of the block */
689 };
690
691 #ifdef __KERNEL__
692 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
693 {
694         return sb->s_fs_info;
695 }
696 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
697 {
698         return container_of(inode, struct ext4_inode_info, vfs_inode);
699 }
700
701 static inline struct timespec ext4_current_time(struct inode *inode)
702 {
703         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
704                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
705 }
706
707
708 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
709 {
710         return ino == EXT4_ROOT_INO ||
711                 ino == EXT4_JOURNAL_INO ||
712                 ino == EXT4_RESIZE_INO ||
713                 (ino >= EXT4_FIRST_INO(sb) &&
714                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
715 }
716 #else
717 /* Assume that user mode programs are passing in an ext4fs superblock, not
718  * a kernel struct super_block.  This will allow us to call the feature-test
719  * macros from user land. */
720 #define EXT4_SB(sb)     (sb)
721 #endif
722
723 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
724
725 /*
726  * Codes for operating systems
727  */
728 #define EXT4_OS_LINUX           0
729 #define EXT4_OS_HURD            1
730 #define EXT4_OS_MASIX           2
731 #define EXT4_OS_FREEBSD         3
732 #define EXT4_OS_LITES           4
733
734 /*
735  * Revision levels
736  */
737 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
738 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
739
740 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
741 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
742
743 #define EXT4_GOOD_OLD_INODE_SIZE 128
744
745 /*
746  * Feature set definitions
747  */
748
749 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
750         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
751 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
752         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
753 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
754         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
755 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
756         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
757 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
758         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
759 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
760         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
761 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
762         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
763 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
764         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
765 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
766         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
767
768 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
769 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
770 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
771 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
772 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
773 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
774
775 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
776 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
777 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
778 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
779 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
780 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
781 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
782
783 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
784 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
785 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
786 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
787 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
788 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
789 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
790 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
791 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
792
793 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
794 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
795                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
796                                          EXT4_FEATURE_INCOMPAT_META_BG| \
797                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
798                                          EXT4_FEATURE_INCOMPAT_64BIT| \
799                                          EXT4_FEATURE_INCOMPAT_FLEX_BG)
800 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
801                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
802                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
803                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
804                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
805                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
806                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
807
808 /*
809  * Default values for user and/or group using reserved blocks
810  */
811 #define EXT4_DEF_RESUID         0
812 #define EXT4_DEF_RESGID         0
813
814 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
815
816 /*
817  * Default mount options
818  */
819 #define EXT4_DEFM_DEBUG         0x0001
820 #define EXT4_DEFM_BSDGROUPS     0x0002
821 #define EXT4_DEFM_XATTR_USER    0x0004
822 #define EXT4_DEFM_ACL           0x0008
823 #define EXT4_DEFM_UID16         0x0010
824 #define EXT4_DEFM_JMODE         0x0060
825 #define EXT4_DEFM_JMODE_DATA    0x0020
826 #define EXT4_DEFM_JMODE_ORDERED 0x0040
827 #define EXT4_DEFM_JMODE_WBACK   0x0060
828
829 /*
830  * Default journal batch times
831  */
832 #define EXT4_DEF_MIN_BATCH_TIME 0
833 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
834
835 /*
836  * Minimum number of groups in a flexgroup before we separate out
837  * directories into the first block group of a flexgroup
838  */
839 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
840
841 /*
842  * Structure of a directory entry
843  */
844 #define EXT4_NAME_LEN 255
845
846 struct ext4_dir_entry {
847         __le32  inode;                  /* Inode number */
848         __le16  rec_len;                /* Directory entry length */
849         __le16  name_len;               /* Name length */
850         char    name[EXT4_NAME_LEN];    /* File name */
851 };
852
853 /*
854  * The new version of the directory entry.  Since EXT4 structures are
855  * stored in intel byte order, and the name_len field could never be
856  * bigger than 255 chars, it's safe to reclaim the extra byte for the
857  * file_type field.
858  */
859 struct ext4_dir_entry_2 {
860         __le32  inode;                  /* Inode number */
861         __le16  rec_len;                /* Directory entry length */
862         __u8    name_len;               /* Name length */
863         __u8    file_type;
864         char    name[EXT4_NAME_LEN];    /* File name */
865 };
866
867 /*
868  * Ext4 directory file types.  Only the low 3 bits are used.  The
869  * other bits are reserved for now.
870  */
871 #define EXT4_FT_UNKNOWN         0
872 #define EXT4_FT_REG_FILE        1
873 #define EXT4_FT_DIR             2
874 #define EXT4_FT_CHRDEV          3
875 #define EXT4_FT_BLKDEV          4
876 #define EXT4_FT_FIFO            5
877 #define EXT4_FT_SOCK            6
878 #define EXT4_FT_SYMLINK         7
879
880 #define EXT4_FT_MAX             8
881
882 /*
883  * EXT4_DIR_PAD defines the directory entries boundaries
884  *
885  * NOTE: It must be a multiple of 4
886  */
887 #define EXT4_DIR_PAD                    4
888 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
889 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
890                                          ~EXT4_DIR_ROUND)
891 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
892
893 /*
894  * Hash Tree Directory indexing
895  * (c) Daniel Phillips, 2001
896  */
897
898 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
899                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
900                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
901 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
902 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
903
904 /* Legal values for the dx_root hash_version field: */
905
906 #define DX_HASH_LEGACY          0
907 #define DX_HASH_HALF_MD4        1
908 #define DX_HASH_TEA             2
909 #define DX_HASH_LEGACY_UNSIGNED 3
910 #define DX_HASH_HALF_MD4_UNSIGNED       4
911 #define DX_HASH_TEA_UNSIGNED            5
912
913 #ifdef __KERNEL__
914
915 /* hash info structure used by the directory hash */
916 struct dx_hash_info
917 {
918         u32             hash;
919         u32             minor_hash;
920         int             hash_version;
921         u32             *seed;
922 };
923
924 #define EXT4_HTREE_EOF  0x7fffffff
925
926 /*
927  * Control parameters used by ext4_htree_next_block
928  */
929 #define HASH_NB_ALWAYS          1
930
931
932 /*
933  * Describe an inode's exact location on disk and in memory
934  */
935 struct ext4_iloc
936 {
937         struct buffer_head *bh;
938         unsigned long offset;
939         ext4_group_t block_group;
940 };
941
942 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
943 {
944         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
945 }
946
947 /*
948  * This structure is stuffed into the struct file's private_data field
949  * for directories.  It is where we put information so that we can do
950  * readdir operations in hash tree order.
951  */
952 struct dir_private_info {
953         struct rb_root  root;
954         struct rb_node  *curr_node;
955         struct fname    *extra_fname;
956         loff_t          last_pos;
957         __u32           curr_hash;
958         __u32           curr_minor_hash;
959         __u32           next_hash;
960 };
961
962 /* calculate the first block number of the group */
963 static inline ext4_fsblk_t
964 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
965 {
966         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
967                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
968 }
969
970 /*
971  * Special error return code only used by dx_probe() and its callers.
972  */
973 #define ERR_BAD_DX_DIR  -75000
974
975 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
976                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
977
978 extern struct proc_dir_entry *ext4_proc_root;
979
980 /*
981  * Function prototypes
982  */
983
984 /*
985  * Ok, these declarations are also in <linux/kernel.h> but none of the
986  * ext4 source programs needs to include it so they are duplicated here.
987  */
988 # define NORET_TYPE     /**/
989 # define ATTRIB_NORET   __attribute__((noreturn))
990 # define NORET_AND      noreturn,
991
992 /* bitmap.c */
993 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
994
995 /* balloc.c */
996 extern unsigned int ext4_block_group(struct super_block *sb,
997                         ext4_fsblk_t blocknr);
998 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
999                         ext4_fsblk_t blocknr);
1000 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1001 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1002                         ext4_group_t group);
1003 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1004                         ext4_fsblk_t goal, unsigned long *count, int *errp);
1005 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1006 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1007 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1008                         ext4_fsblk_t block, unsigned long count, int metadata);
1009 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1010                                 ext4_fsblk_t block, unsigned long count);
1011 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1012 extern void ext4_check_blocks_bitmap(struct super_block *);
1013 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1014                                                     ext4_group_t block_group,
1015                                                     struct buffer_head ** bh);
1016 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1017
1018 /* dir.c */
1019 extern int ext4_check_dir_entry(const char *, struct inode *,
1020                                 struct ext4_dir_entry_2 *,
1021                                 struct buffer_head *, unsigned int);
1022 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1023                                     __u32 minor_hash,
1024                                     struct ext4_dir_entry_2 *dirent);
1025 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1026
1027 /* fsync.c */
1028 extern int ext4_sync_file(struct file *, struct dentry *, int);
1029
1030 /* hash.c */
1031 extern int ext4fs_dirhash(const char *name, int len, struct
1032                           dx_hash_info *hinfo);
1033
1034 /* ialloc.c */
1035 extern struct inode * ext4_new_inode(handle_t *, struct inode *, int);
1036 extern void ext4_free_inode(handle_t *, struct inode *);
1037 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1038 extern unsigned long ext4_count_free_inodes(struct super_block *);
1039 extern unsigned long ext4_count_dirs(struct super_block *);
1040 extern void ext4_check_inodes_bitmap(struct super_block *);
1041
1042 /* mballoc.c */
1043 extern long ext4_mb_stats;
1044 extern long ext4_mb_max_to_scan;
1045 extern int ext4_mb_init(struct super_block *, int);
1046 extern int ext4_mb_release(struct super_block *);
1047 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1048                                 struct ext4_allocation_request *, int *);
1049 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1050 extern void ext4_discard_preallocations(struct inode *);
1051 extern int __init init_ext4_mballoc(void);
1052 extern void exit_ext4_mballoc(void);
1053 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
1054                 unsigned long, unsigned long, int, unsigned long *);
1055 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1056                 ext4_group_t i, struct ext4_group_desc *desc);
1057 extern void ext4_mb_update_group_info(struct ext4_group_info *grp,
1058                 ext4_grpblk_t add);
1059 extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1060 extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1061                                                 ext4_group_t, int);
1062 /* inode.c */
1063 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
1064                 struct buffer_head *bh, ext4_fsblk_t blocknr);
1065 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1066                                                 ext4_lblk_t, int, int *);
1067 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1068                                                 ext4_lblk_t, int, int *);
1069 int ext4_get_block(struct inode *inode, sector_t iblock,
1070                                 struct buffer_head *bh_result, int create);
1071
1072 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1073 extern int  ext4_write_inode(struct inode *, int);
1074 extern int  ext4_setattr(struct dentry *, struct iattr *);
1075 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1076                                 struct kstat *stat);
1077 extern void ext4_delete_inode(struct inode *);
1078 extern int  ext4_sync_inode(handle_t *, struct inode *);
1079 extern void ext4_dirty_inode(struct inode *);
1080 extern int ext4_change_inode_journal_flag(struct inode *, int);
1081 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1082 extern int ext4_can_truncate(struct inode *inode);
1083 extern void ext4_truncate(struct inode *);
1084 extern void ext4_set_inode_flags(struct inode *);
1085 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1086 extern int ext4_alloc_da_blocks(struct inode *inode);
1087 extern void ext4_set_aops(struct inode *inode);
1088 extern int ext4_writepage_trans_blocks(struct inode *);
1089 extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1090 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1091 extern int ext4_block_truncate_page(handle_t *handle,
1092                 struct address_space *mapping, loff_t from);
1093 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1094 extern qsize_t ext4_get_reserved_space(struct inode *inode);
1095
1096 /* ioctl.c */
1097 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1098 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1099
1100 /* migrate.c */
1101 extern int ext4_ext_migrate(struct inode *);
1102
1103 /* namei.c */
1104 extern unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize);
1105 extern __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize);
1106 extern int ext4_orphan_add(handle_t *, struct inode *);
1107 extern int ext4_orphan_del(handle_t *, struct inode *);
1108 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1109                                 __u32 start_minor_hash, __u32 *next_hash);
1110
1111 /* resize.c */
1112 extern int ext4_group_add(struct super_block *sb,
1113                                 struct ext4_new_group_data *input);
1114 extern int ext4_group_extend(struct super_block *sb,
1115                                 struct ext4_super_block *es,
1116                                 ext4_fsblk_t n_blocks_count);
1117
1118 /* super.c */
1119 extern void ext4_error(struct super_block *, const char *, const char *, ...)
1120         __attribute__ ((format (printf, 3, 4)));
1121 extern void __ext4_std_error(struct super_block *, const char *, int);
1122 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
1123         __attribute__ ((format (printf, 3, 4)));
1124 extern void ext4_warning(struct super_block *, const char *, const char *, ...)
1125         __attribute__ ((format (printf, 3, 4)));
1126 extern void ext4_grp_locked_error(struct super_block *, ext4_group_t,
1127                                 const char *, const char *, ...)
1128         __attribute__ ((format (printf, 4, 5)));
1129 extern void ext4_update_dynamic_rev(struct super_block *sb);
1130 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1131                                         __u32 compat);
1132 extern int ext4_update_rocompat_feature(handle_t *handle,
1133                                         struct super_block *sb, __u32 rocompat);
1134 extern int ext4_update_incompat_feature(handle_t *handle,
1135                                         struct super_block *sb, __u32 incompat);
1136 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1137                                       struct ext4_group_desc *bg);
1138 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1139                                       struct ext4_group_desc *bg);
1140 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1141                                      struct ext4_group_desc *bg);
1142 extern __u32 ext4_free_blks_count(struct super_block *sb,
1143                                 struct ext4_group_desc *bg);
1144 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1145                                  struct ext4_group_desc *bg);
1146 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1147                                 struct ext4_group_desc *bg);
1148 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1149                                    struct ext4_group_desc *bg);
1150 extern void ext4_block_bitmap_set(struct super_block *sb,
1151                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1152 extern void ext4_inode_bitmap_set(struct super_block *sb,
1153                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1154 extern void ext4_inode_table_set(struct super_block *sb,
1155                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1156 extern void ext4_free_blks_set(struct super_block *sb,
1157                                struct ext4_group_desc *bg, __u32 count);
1158 extern void ext4_free_inodes_set(struct super_block *sb,
1159                                 struct ext4_group_desc *bg, __u32 count);
1160 extern void ext4_used_dirs_set(struct super_block *sb,
1161                                 struct ext4_group_desc *bg, __u32 count);
1162 extern void ext4_itable_unused_set(struct super_block *sb,
1163                                    struct ext4_group_desc *bg, __u32 count);
1164
1165 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1166 {
1167         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1168                 le32_to_cpu(es->s_blocks_count_lo);
1169 }
1170
1171 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1172 {
1173         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1174                 le32_to_cpu(es->s_r_blocks_count_lo);
1175 }
1176
1177 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1178 {
1179         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1180                 le32_to_cpu(es->s_free_blocks_count_lo);
1181 }
1182
1183 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1184                                          ext4_fsblk_t blk)
1185 {
1186         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1187         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1188 }
1189
1190 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1191                                               ext4_fsblk_t blk)
1192 {
1193         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1194         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1195 }
1196
1197 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1198                                            ext4_fsblk_t blk)
1199 {
1200         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1201         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1202 }
1203
1204 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1205 {
1206         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1207                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1208                         le32_to_cpu(raw_inode->i_size_lo);
1209         else
1210                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1211 }
1212
1213 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1214 {
1215         raw_inode->i_size_lo = cpu_to_le32(i_size);
1216         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1217 }
1218
1219 static inline
1220 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1221                                             ext4_group_t group)
1222 {
1223          struct ext4_group_info ***grp_info;
1224          long indexv, indexh;
1225          grp_info = EXT4_SB(sb)->s_group_info;
1226          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1227          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1228          return grp_info[indexv][indexh];
1229 }
1230
1231
1232 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1233                                              ext4_group_t block_group)
1234 {
1235         return block_group >> sbi->s_log_groups_per_flex;
1236 }
1237
1238 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1239 {
1240         return 1 << sbi->s_log_groups_per_flex;
1241 }
1242
1243 #define ext4_std_error(sb, errno)                               \
1244 do {                                                            \
1245         if ((errno))                                            \
1246                 __ext4_std_error((sb), __func__, (errno));      \
1247 } while (0)
1248
1249 #ifdef CONFIG_SMP
1250 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1251  * counters. So we need to make sure we have free blocks more
1252  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1253  */
1254 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1255 #else
1256 #define EXT4_FREEBLOCKS_WATERMARK 0
1257 #endif
1258
1259 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1260 {
1261         /*
1262          * XXX: replace with spinlock if seen contended -bzzz
1263          */
1264         down_write(&EXT4_I(inode)->i_data_sem);
1265         if (newsize > EXT4_I(inode)->i_disksize)
1266                 EXT4_I(inode)->i_disksize = newsize;
1267         up_write(&EXT4_I(inode)->i_data_sem);
1268         return ;
1269 }
1270
1271 struct ext4_group_info {
1272         unsigned long   bb_state;
1273         struct rb_root  bb_free_root;
1274         unsigned short  bb_first_free;
1275         unsigned short  bb_free;
1276         unsigned short  bb_fragments;
1277         struct          list_head bb_prealloc_list;
1278 #ifdef DOUBLE_CHECK
1279         void            *bb_bitmap;
1280 #endif
1281         struct rw_semaphore alloc_sem;
1282         unsigned short  bb_counters[];
1283 };
1284
1285 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
1286 #define EXT4_GROUP_INFO_LOCKED_BIT      1
1287
1288 #define EXT4_MB_GRP_NEED_INIT(grp)      \
1289         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1290
1291 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1292 {
1293         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1294
1295         bit_spin_lock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1296 }
1297
1298 static inline void ext4_unlock_group(struct super_block *sb,
1299                                         ext4_group_t group)
1300 {
1301         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1302
1303         bit_spin_unlock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1304 }
1305
1306 static inline int ext4_is_group_locked(struct super_block *sb,
1307                                         ext4_group_t group)
1308 {
1309         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1310
1311         return bit_spin_is_locked(EXT4_GROUP_INFO_LOCKED_BIT,
1312                                                 &(grinfo->bb_state));
1313 }
1314
1315 /*
1316  * Inodes and files operations
1317  */
1318
1319 /* dir.c */
1320 extern const struct file_operations ext4_dir_operations;
1321
1322 /* file.c */
1323 extern const struct inode_operations ext4_file_inode_operations;
1324 extern const struct file_operations ext4_file_operations;
1325
1326 /* namei.c */
1327 extern const struct inode_operations ext4_dir_inode_operations;
1328 extern const struct inode_operations ext4_special_inode_operations;
1329
1330 /* symlink.c */
1331 extern const struct inode_operations ext4_symlink_inode_operations;
1332 extern const struct inode_operations ext4_fast_symlink_inode_operations;
1333
1334 /* extents.c */
1335 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1336 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1337 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1338                                        int chunk);
1339 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1340                                ext4_lblk_t iblock, unsigned int max_blocks,
1341                                struct buffer_head *bh_result,
1342                                int create, int extend_disksize);
1343 extern void ext4_ext_truncate(struct inode *);
1344 extern void ext4_ext_init(struct super_block *);
1345 extern void ext4_ext_release(struct super_block *);
1346 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1347                           loff_t len);
1348 extern int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode,
1349                         sector_t block, unsigned int max_blocks,
1350                         struct buffer_head *bh, int create,
1351                         int extend_disksize, int flag);
1352 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1353                         __u64 start, __u64 len);
1354
1355 /*
1356  * Add new method to test wether block and inode bitmaps are properly
1357  * initialized. With uninit_bg reading the block from disk is not enough
1358  * to mark the bitmap uptodate. We need to also zero-out the bitmap
1359  */
1360 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
1361
1362 static inline int bitmap_uptodate(struct buffer_head *bh)
1363 {
1364         return (buffer_uptodate(bh) &&
1365                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
1366 }
1367 static inline void set_bitmap_uptodate(struct buffer_head *bh)
1368 {
1369         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
1370 }
1371
1372 #endif  /* __KERNEL__ */
1373
1374 #endif  /* _EXT4_H */