ext4: add flag to ext4_has_free_blocks
[linux-2.6.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 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
148                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
149                                  EXT4_MAP_UNINIT)
150
151 struct ext4_map_blocks {
152         ext4_fsblk_t m_pblk;
153         ext4_lblk_t m_lblk;
154         unsigned int m_len;
155         unsigned int m_flags;
156 };
157
158 /*
159  * For delayed allocation tracking
160  */
161 struct mpage_da_data {
162         struct inode *inode;
163         sector_t b_blocknr;             /* start block number of extent */
164         size_t b_size;                  /* size of extent */
165         unsigned long b_state;          /* state of the extent */
166         unsigned long first_page, next_page;    /* extent of pages */
167         struct writeback_control *wbc;
168         int io_done;
169         int pages_written;
170         int retval;
171 };
172
173 /*
174  * Flags for ext4_io_end->flags
175  */
176 #define EXT4_IO_END_UNWRITTEN   0x0001
177 #define EXT4_IO_END_ERROR       0x0002
178
179 struct ext4_io_page {
180         struct page     *p_page;
181         atomic_t        p_count;
182 };
183
184 #define MAX_IO_PAGES 128
185
186 typedef struct ext4_io_end {
187         struct list_head        list;           /* per-file finished IO list */
188         struct inode            *inode;         /* file being written to */
189         unsigned int            flag;           /* unwritten or not */
190         struct page             *page;          /* page struct for buffer write */
191         loff_t                  offset;         /* offset in the file */
192         ssize_t                 size;           /* size of the extent */
193         struct work_struct      work;           /* data work queue */
194         struct kiocb            *iocb;          /* iocb struct for AIO */
195         int                     result;         /* error value for AIO */
196         int                     num_io_pages;
197         struct ext4_io_page     *pages[MAX_IO_PAGES];
198 } ext4_io_end_t;
199
200 struct ext4_io_submit {
201         int                     io_op;
202         struct bio              *io_bio;
203         ext4_io_end_t           *io_end;
204         struct ext4_io_page     *io_page;
205         sector_t                io_next_block;
206 };
207
208 /*
209  * Special inodes numbers
210  */
211 #define EXT4_BAD_INO             1      /* Bad blocks inode */
212 #define EXT4_ROOT_INO            2      /* Root inode */
213 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
214 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
215 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
216 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
217 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
218 #define EXT4_JOURNAL_INO         8      /* Journal inode */
219
220 /* First non-reserved inode for old ext4 filesystems */
221 #define EXT4_GOOD_OLD_FIRST_INO 11
222
223 /*
224  * Maximal count of links to a file
225  */
226 #define EXT4_LINK_MAX           65000
227
228 /*
229  * Macro-instructions used to manage several block sizes
230  */
231 #define EXT4_MIN_BLOCK_SIZE             1024
232 #define EXT4_MAX_BLOCK_SIZE             65536
233 #define EXT4_MIN_BLOCK_LOG_SIZE         10
234 #define EXT4_MAX_BLOCK_LOG_SIZE         16
235 #ifdef __KERNEL__
236 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
237 #else
238 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
239 #endif
240 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
241 #ifdef __KERNEL__
242 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
243 #else
244 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
245 #endif
246 #ifdef __KERNEL__
247 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
248 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
249 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
250 #else
251 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
252                                  EXT4_GOOD_OLD_INODE_SIZE : \
253                                  (s)->s_inode_size)
254 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
255                                  EXT4_GOOD_OLD_FIRST_INO : \
256                                  (s)->s_first_ino)
257 #endif
258 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
259
260 /*
261  * Structure of a blocks group descriptor
262  */
263 struct ext4_group_desc
264 {
265         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
266         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
267         __le32  bg_inode_table_lo;      /* Inodes table block */
268         __le16  bg_free_blocks_count_lo;/* Free blocks count */
269         __le16  bg_free_inodes_count_lo;/* Free inodes count */
270         __le16  bg_used_dirs_count_lo;  /* Directories count */
271         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
272         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
273         __le16  bg_itable_unused_lo;    /* Unused inodes count */
274         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
275         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
276         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
277         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
278         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
279         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
280         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
281         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
282         __u32   bg_reserved2[3];
283 };
284
285 /*
286  * Structure of a flex block group info
287  */
288
289 struct flex_groups {
290         atomic_t free_inodes;
291         atomic_t free_blocks;
292         atomic_t used_dirs;
293 };
294
295 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
296 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
297 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
298
299 /*
300  * Macro-instructions used to manage group descriptors
301  */
302 #define EXT4_MIN_DESC_SIZE              32
303 #define EXT4_MIN_DESC_SIZE_64BIT        64
304 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
305 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
306 #ifdef __KERNEL__
307 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
308 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
309 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
310 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
311 #else
312 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
313 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
314 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
315 #endif
316
317 /*
318  * Constants relative to the data blocks
319  */
320 #define EXT4_NDIR_BLOCKS                12
321 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
322 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
323 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
324 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
325
326 /*
327  * Inode flags
328  */
329 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
330 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
331 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
332 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
333 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
334 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
335 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
336 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
337 /* Reserved for compression usage... */
338 #define EXT4_DIRTY_FL                   0x00000100
339 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
340 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
341 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
342 /* End compression flags --- maybe not all used */
343 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
344 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
345 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
346 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
347 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
348 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
349 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
350 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
351 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
352 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
353 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
354
355 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
356 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
357
358 /* Flags that should be inherited by new inodes from their parent. */
359 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
360                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
361                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
362                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
363                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
364
365 /* Flags that are appropriate for regular files (all but dir-specific ones). */
366 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
367
368 /* Flags that are appropriate for non-directories/regular files. */
369 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
370
371 /* Mask out flags that are inappropriate for the given type of inode. */
372 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
373 {
374         if (S_ISDIR(mode))
375                 return flags;
376         else if (S_ISREG(mode))
377                 return flags & EXT4_REG_FLMASK;
378         else
379                 return flags & EXT4_OTHER_FLMASK;
380 }
381
382 /*
383  * Inode flags used for atomic set/get
384  */
385 enum {
386         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
387         EXT4_INODE_UNRM         = 1,    /* Undelete */
388         EXT4_INODE_COMPR        = 2,    /* Compress file */
389         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
390         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
391         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
392         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
393         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
394 /* Reserved for compression usage... */
395         EXT4_INODE_DIRTY        = 8,
396         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
397         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
398         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
399 /* End compression flags --- maybe not all used */
400         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
401         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
402         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
403         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
404         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
405         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
406         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
407         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
408         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
409         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
410         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
411 };
412
413 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
414 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
415         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
416                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
417
418 /*
419  * Since it's pretty easy to mix up bit numbers and hex values, and we
420  * can't do a compile-time test for ENUM values, we use a run-time
421  * test to make sure that EXT4_XXX_FL is consistent with respect to
422  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
423  * out so it won't cost any extra space in the compiled kernel image.
424  * But it's important that these values are the same, since we are
425  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
426  * must be consistent with the values of FS_XXX_FL defined in
427  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
428  * ext4 filesystems, and of course the values defined in e2fsprogs.
429  *
430  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
431  */
432 static inline void ext4_check_flag_values(void)
433 {
434         CHECK_FLAG_VALUE(SECRM);
435         CHECK_FLAG_VALUE(UNRM);
436         CHECK_FLAG_VALUE(COMPR);
437         CHECK_FLAG_VALUE(SYNC);
438         CHECK_FLAG_VALUE(IMMUTABLE);
439         CHECK_FLAG_VALUE(APPEND);
440         CHECK_FLAG_VALUE(NODUMP);
441         CHECK_FLAG_VALUE(NOATIME);
442         CHECK_FLAG_VALUE(DIRTY);
443         CHECK_FLAG_VALUE(COMPRBLK);
444         CHECK_FLAG_VALUE(NOCOMPR);
445         CHECK_FLAG_VALUE(ECOMPR);
446         CHECK_FLAG_VALUE(INDEX);
447         CHECK_FLAG_VALUE(IMAGIC);
448         CHECK_FLAG_VALUE(JOURNAL_DATA);
449         CHECK_FLAG_VALUE(NOTAIL);
450         CHECK_FLAG_VALUE(DIRSYNC);
451         CHECK_FLAG_VALUE(TOPDIR);
452         CHECK_FLAG_VALUE(HUGE_FILE);
453         CHECK_FLAG_VALUE(EXTENTS);
454         CHECK_FLAG_VALUE(EA_INODE);
455         CHECK_FLAG_VALUE(EOFBLOCKS);
456         CHECK_FLAG_VALUE(RESERVED);
457 }
458
459 /* Used to pass group descriptor data when online resize is done */
460 struct ext4_new_group_input {
461         __u32 group;            /* Group number for this data */
462         __u64 block_bitmap;     /* Absolute block number of block bitmap */
463         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
464         __u64 inode_table;      /* Absolute block number of inode table start */
465         __u32 blocks_count;     /* Total number of blocks in this group */
466         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
467         __u16 unused;
468 };
469
470 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
471 struct compat_ext4_new_group_input {
472         u32 group;
473         compat_u64 block_bitmap;
474         compat_u64 inode_bitmap;
475         compat_u64 inode_table;
476         u32 blocks_count;
477         u16 reserved_blocks;
478         u16 unused;
479 };
480 #endif
481
482 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
483 struct ext4_new_group_data {
484         __u32 group;
485         __u64 block_bitmap;
486         __u64 inode_bitmap;
487         __u64 inode_table;
488         __u32 blocks_count;
489         __u16 reserved_blocks;
490         __u16 unused;
491         __u32 free_blocks_count;
492 };
493
494 /*
495  * Flags used by ext4_map_blocks()
496  */
497         /* Allocate any needed blocks and/or convert an unitialized
498            extent to be an initialized ext4 */
499 #define EXT4_GET_BLOCKS_CREATE                  0x0001
500         /* Request the creation of an unitialized extent */
501 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
502 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
503                                                  EXT4_GET_BLOCKS_CREATE)
504         /* Caller is from the delayed allocation writeout path,
505            so set the magic i_delalloc_reserve_flag after taking the
506            inode allocation semaphore for */
507 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
508         /* caller is from the direct IO path, request to creation of an
509         unitialized extents if not allocated, split the uninitialized
510         extent if blocks has been preallocated already*/
511 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
512 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
513 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
514                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
515         /* Convert extent to initialized after IO complete */
516 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
517                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
518         /* Punch out blocks of an extent */
519 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
520
521 /*
522  * Flags used by ext4_free_blocks
523  */
524 #define EXT4_FREE_BLOCKS_METADATA       0x0001
525 #define EXT4_FREE_BLOCKS_FORGET         0x0002
526 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
527
528 /*
529  * ioctl commands
530  */
531 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
532 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
533 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
534 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
535 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
536 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
537 #ifdef CONFIG_JBD2_DEBUG
538 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
539 #endif
540 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
541 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
542 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
543 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
544 #define EXT4_IOC_MIGRATE                _IO('f', 9)
545  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
546  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
547 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
548 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
549
550 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
551 /*
552  * ioctl commands in 32 bit emulation
553  */
554 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
555 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
556 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
557 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
558 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
559 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
560 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
561 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
562 #ifdef CONFIG_JBD2_DEBUG
563 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
564 #endif
565 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
566 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
567 #endif
568
569 /* Max physical block we can address w/o extents */
570 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
571
572 /*
573  * Structure of an inode on the disk
574  */
575 struct ext4_inode {
576         __le16  i_mode;         /* File mode */
577         __le16  i_uid;          /* Low 16 bits of Owner Uid */
578         __le32  i_size_lo;      /* Size in bytes */
579         __le32  i_atime;        /* Access time */
580         __le32  i_ctime;        /* Inode Change time */
581         __le32  i_mtime;        /* Modification time */
582         __le32  i_dtime;        /* Deletion Time */
583         __le16  i_gid;          /* Low 16 bits of Group Id */
584         __le16  i_links_count;  /* Links count */
585         __le32  i_blocks_lo;    /* Blocks count */
586         __le32  i_flags;        /* File flags */
587         union {
588                 struct {
589                         __le32  l_i_version;
590                 } linux1;
591                 struct {
592                         __u32  h_i_translator;
593                 } hurd1;
594                 struct {
595                         __u32  m_i_reserved1;
596                 } masix1;
597         } osd1;                         /* OS dependent 1 */
598         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
599         __le32  i_generation;   /* File version (for NFS) */
600         __le32  i_file_acl_lo;  /* File ACL */
601         __le32  i_size_high;
602         __le32  i_obso_faddr;   /* Obsoleted fragment address */
603         union {
604                 struct {
605                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
606                         __le16  l_i_file_acl_high;
607                         __le16  l_i_uid_high;   /* these 2 fields */
608                         __le16  l_i_gid_high;   /* were reserved2[0] */
609                         __u32   l_i_reserved2;
610                 } linux2;
611                 struct {
612                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
613                         __u16   h_i_mode_high;
614                         __u16   h_i_uid_high;
615                         __u16   h_i_gid_high;
616                         __u32   h_i_author;
617                 } hurd2;
618                 struct {
619                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
620                         __le16  m_i_file_acl_high;
621                         __u32   m_i_reserved2[2];
622                 } masix2;
623         } osd2;                         /* OS dependent 2 */
624         __le16  i_extra_isize;
625         __le16  i_pad1;
626         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
627         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
628         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
629         __le32  i_crtime;       /* File Creation time */
630         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
631         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
632 };
633
634 struct move_extent {
635         __u32 reserved;         /* should be zero */
636         __u32 donor_fd;         /* donor file descriptor */
637         __u64 orig_start;       /* logical start offset in block for orig */
638         __u64 donor_start;      /* logical start offset in block for donor */
639         __u64 len;              /* block length to be moved */
640         __u64 moved_len;        /* moved block length */
641 };
642
643 #define EXT4_EPOCH_BITS 2
644 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
645 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
646
647 /*
648  * Extended fields will fit into an inode if the filesystem was formatted
649  * with large inodes (-I 256 or larger) and there are not currently any EAs
650  * consuming all of the available space. For new inodes we always reserve
651  * enough space for the kernel's known extended fields, but for inodes
652  * created with an old kernel this might not have been the case. None of
653  * the extended inode fields is critical for correct filesystem operation.
654  * This macro checks if a certain field fits in the inode. Note that
655  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
656  */
657 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
658         ((offsetof(typeof(*ext4_inode), field) +        \
659           sizeof((ext4_inode)->field))                  \
660         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
661             (einode)->i_extra_isize))                   \
662
663 static inline __le32 ext4_encode_extra_time(struct timespec *time)
664 {
665        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
666                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
667                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
668 }
669
670 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
671 {
672        if (sizeof(time->tv_sec) > 4)
673                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
674                                << 32;
675        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
676 }
677
678 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
679 do {                                                                           \
680         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
681         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
682                 (raw_inode)->xtime ## _extra =                                 \
683                                 ext4_encode_extra_time(&(inode)->xtime);       \
684 } while (0)
685
686 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
687 do {                                                                           \
688         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
689                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
690         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
691                 (raw_inode)->xtime ## _extra =                                 \
692                                 ext4_encode_extra_time(&(einode)->xtime);      \
693 } while (0)
694
695 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
696 do {                                                                           \
697         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
698         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
699                 ext4_decode_extra_time(&(inode)->xtime,                        \
700                                        raw_inode->xtime ## _extra);            \
701         else                                                                   \
702                 (inode)->xtime.tv_nsec = 0;                                    \
703 } while (0)
704
705 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
706 do {                                                                           \
707         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
708                 (einode)->xtime.tv_sec =                                       \
709                         (signed)le32_to_cpu((raw_inode)->xtime);               \
710         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
711                 ext4_decode_extra_time(&(einode)->xtime,                       \
712                                        raw_inode->xtime ## _extra);            \
713         else                                                                   \
714                 (einode)->xtime.tv_nsec = 0;                                   \
715 } while (0)
716
717 #define i_disk_version osd1.linux1.l_i_version
718
719 #if defined(__KERNEL__) || defined(__linux__)
720 #define i_reserved1     osd1.linux1.l_i_reserved1
721 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
722 #define i_blocks_high   osd2.linux2.l_i_blocks_high
723 #define i_uid_low       i_uid
724 #define i_gid_low       i_gid
725 #define i_uid_high      osd2.linux2.l_i_uid_high
726 #define i_gid_high      osd2.linux2.l_i_gid_high
727 #define i_reserved2     osd2.linux2.l_i_reserved2
728
729 #elif defined(__GNU__)
730
731 #define i_translator    osd1.hurd1.h_i_translator
732 #define i_uid_high      osd2.hurd2.h_i_uid_high
733 #define i_gid_high      osd2.hurd2.h_i_gid_high
734 #define i_author        osd2.hurd2.h_i_author
735
736 #elif defined(__masix__)
737
738 #define i_reserved1     osd1.masix1.m_i_reserved1
739 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
740 #define i_reserved2     osd2.masix2.m_i_reserved2
741
742 #endif /* defined(__KERNEL__) || defined(__linux__) */
743
744 /*
745  * storage for cached extent
746  * If ec_len == 0, then the cache is invalid.
747  * If ec_start == 0, then the cache represents a gap (null mapping)
748  */
749 struct ext4_ext_cache {
750         ext4_fsblk_t    ec_start;
751         ext4_lblk_t     ec_block;
752         __u32           ec_len; /* must be 32bit to return holes */
753 };
754
755 /*
756  * fourth extended file system inode data in memory
757  */
758 struct ext4_inode_info {
759         __le32  i_data[15];     /* unconverted */
760         __u32   i_dtime;
761         ext4_fsblk_t    i_file_acl;
762
763         /*
764          * i_block_group is the number of the block group which contains
765          * this file's inode.  Constant across the lifetime of the inode,
766          * it is ued for making block allocation decisions - we try to
767          * place a file's data blocks near its inode block, and new inodes
768          * near to their parent directory's inode.
769          */
770         ext4_group_t    i_block_group;
771         ext4_lblk_t     i_dir_start_lookup;
772 #if (BITS_PER_LONG < 64)
773         unsigned long   i_state_flags;          /* Dynamic state flags */
774 #endif
775         unsigned long   i_flags;
776
777 #ifdef CONFIG_EXT4_FS_XATTR
778         /*
779          * Extended attributes can be read independently of the main file
780          * data. Taking i_mutex even when reading would cause contention
781          * between readers of EAs and writers of regular file data, so
782          * instead we synchronize on xattr_sem when reading or changing
783          * EAs.
784          */
785         struct rw_semaphore xattr_sem;
786 #endif
787
788         struct list_head i_orphan;      /* unlinked but open inodes */
789
790         /*
791          * i_disksize keeps track of what the inode size is ON DISK, not
792          * in memory.  During truncate, i_size is set to the new size by
793          * the VFS prior to calling ext4_truncate(), but the filesystem won't
794          * set i_disksize to 0 until the truncate is actually under way.
795          *
796          * The intent is that i_disksize always represents the blocks which
797          * are used by this file.  This allows recovery to restart truncate
798          * on orphans if we crash during truncate.  We actually write i_disksize
799          * into the on-disk inode when writing inodes out, instead of i_size.
800          *
801          * The only time when i_disksize and i_size may be different is when
802          * a truncate is in progress.  The only things which change i_disksize
803          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
804          */
805         loff_t  i_disksize;
806
807         /*
808          * i_data_sem is for serialising ext4_truncate() against
809          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
810          * data tree are chopped off during truncate. We can't do that in
811          * ext4 because whenever we perform intermediate commits during
812          * truncate, the inode and all the metadata blocks *must* be in a
813          * consistent state which allows truncation of the orphans to restart
814          * during recovery.  Hence we must fix the get_block-vs-truncate race
815          * by other means, so we have i_data_sem.
816          */
817         struct rw_semaphore i_data_sem;
818         struct inode vfs_inode;
819         struct jbd2_inode *jinode;
820
821         struct ext4_ext_cache i_cached_extent;
822         /*
823          * File creation time. Its function is same as that of
824          * struct timespec i_{a,c,m}time in the generic inode.
825          */
826         struct timespec i_crtime;
827
828         /* mballoc */
829         struct list_head i_prealloc_list;
830         spinlock_t i_prealloc_lock;
831
832         /* ialloc */
833         ext4_group_t    i_last_alloc_group;
834
835         /* allocation reservation info for delalloc */
836         unsigned int i_reserved_data_blocks;
837         unsigned int i_reserved_meta_blocks;
838         unsigned int i_allocated_meta_blocks;
839         ext4_lblk_t i_da_metadata_calc_last_lblock;
840         int i_da_metadata_calc_len;
841
842         /* on-disk additional length */
843         __u16 i_extra_isize;
844
845 #ifdef CONFIG_QUOTA
846         /* quota space reservation, managed internally by quota code */
847         qsize_t i_reserved_quota;
848 #endif
849
850         /* completed IOs that might need unwritten extents handling */
851         struct list_head i_completed_io_list;
852         spinlock_t i_completed_io_lock;
853         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
854         /* current io_end structure for async DIO write*/
855         ext4_io_end_t *cur_aio_dio;
856         atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
857
858         spinlock_t i_block_reservation_lock;
859
860         /*
861          * Transactions that contain inode's metadata needed to complete
862          * fsync and fdatasync, respectively.
863          */
864         tid_t i_sync_tid;
865         tid_t i_datasync_tid;
866 };
867
868 /*
869  * File system states
870  */
871 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
872 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
873 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
874
875 /*
876  * Misc. filesystem flags
877  */
878 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
879 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
880 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
881
882 /*
883  * Mount flags
884  */
885 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
886 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
887 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
888 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
889 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
890 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
891 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
892 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
893 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
894 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
895 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
896 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
897 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
898 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
899 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
900 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
901 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
902 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
903 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
904 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
905 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
906 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
907 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
908 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
909 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
910 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
911 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
912 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
913 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
914 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
915 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
916
917 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
918                                                 ~EXT4_MOUNT_##opt
919 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
920                                                 EXT4_MOUNT_##opt
921 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
922                                          EXT4_MOUNT_##opt)
923
924 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
925                                                 ~EXT4_MOUNT2_##opt
926 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
927                                                 EXT4_MOUNT2_##opt
928 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
929                                          EXT4_MOUNT2_##opt)
930
931 #define ext4_set_bit                    __test_and_set_bit_le
932 #define ext4_set_bit_atomic             ext2_set_bit_atomic
933 #define ext4_clear_bit                  __test_and_clear_bit_le
934 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
935 #define ext4_test_bit                   test_bit_le
936 #define ext4_find_first_zero_bit        find_first_zero_bit_le
937 #define ext4_find_next_zero_bit         find_next_zero_bit_le
938 #define ext4_find_next_bit              find_next_bit_le
939
940 /*
941  * Maximal mount counts between two filesystem checks
942  */
943 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
944 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
945
946 /*
947  * Behaviour when detecting errors
948  */
949 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
950 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
951 #define EXT4_ERRORS_PANIC               3       /* Panic */
952 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
953
954 /*
955  * Structure of the super block
956  */
957 struct ext4_super_block {
958 /*00*/  __le32  s_inodes_count;         /* Inodes count */
959         __le32  s_blocks_count_lo;      /* Blocks count */
960         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
961         __le32  s_free_blocks_count_lo; /* Free blocks count */
962 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
963         __le32  s_first_data_block;     /* First Data Block */
964         __le32  s_log_block_size;       /* Block size */
965         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
966 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
967         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
968         __le32  s_inodes_per_group;     /* # Inodes per group */
969         __le32  s_mtime;                /* Mount time */
970 /*30*/  __le32  s_wtime;                /* Write time */
971         __le16  s_mnt_count;            /* Mount count */
972         __le16  s_max_mnt_count;        /* Maximal mount count */
973         __le16  s_magic;                /* Magic signature */
974         __le16  s_state;                /* File system state */
975         __le16  s_errors;               /* Behaviour when detecting errors */
976         __le16  s_minor_rev_level;      /* minor revision level */
977 /*40*/  __le32  s_lastcheck;            /* time of last check */
978         __le32  s_checkinterval;        /* max. time between checks */
979         __le32  s_creator_os;           /* OS */
980         __le32  s_rev_level;            /* Revision level */
981 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
982         __le16  s_def_resgid;           /* Default gid for reserved blocks */
983         /*
984          * These fields are for EXT4_DYNAMIC_REV superblocks only.
985          *
986          * Note: the difference between the compatible feature set and
987          * the incompatible feature set is that if there is a bit set
988          * in the incompatible feature set that the kernel doesn't
989          * know about, it should refuse to mount the filesystem.
990          *
991          * e2fsck's requirements are more strict; if it doesn't know
992          * about a feature in either the compatible or incompatible
993          * feature set, it must abort and not try to meddle with
994          * things it doesn't understand...
995          */
996         __le32  s_first_ino;            /* First non-reserved inode */
997         __le16  s_inode_size;           /* size of inode structure */
998         __le16  s_block_group_nr;       /* block group # of this superblock */
999         __le32  s_feature_compat;       /* compatible feature set */
1000 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1001         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1002 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1003 /*78*/  char    s_volume_name[16];      /* volume name */
1004 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1005 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1006         /*
1007          * Performance hints.  Directory preallocation should only
1008          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1009          */
1010         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1011         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1012         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1013         /*
1014          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1015          */
1016 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1017 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1018         __le32  s_journal_dev;          /* device number of journal file */
1019         __le32  s_last_orphan;          /* start of list of inodes to delete */
1020         __le32  s_hash_seed[4];         /* HTREE hash seed */
1021         __u8    s_def_hash_version;     /* Default hash version to use */
1022         __u8    s_jnl_backup_type;
1023         __le16  s_desc_size;            /* size of group descriptor */
1024 /*100*/ __le32  s_default_mount_opts;
1025         __le32  s_first_meta_bg;        /* First metablock block group */
1026         __le32  s_mkfs_time;            /* When the filesystem was created */
1027         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1028         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1029 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1030         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1031         __le32  s_free_blocks_count_hi; /* Free blocks count */
1032         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1033         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1034         __le32  s_flags;                /* Miscellaneous flags */
1035         __le16  s_raid_stride;          /* RAID stride */
1036         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1037         __le64  s_mmp_block;            /* Block for multi-mount protection */
1038         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1039         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1040         __u8    s_reserved_char_pad;
1041         __le16  s_reserved_pad;
1042         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1043         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1044         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1045         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1046                                               snapshot's future use */
1047         __le32  s_snapshot_list;        /* inode number of the head of the
1048                                            on-disk snapshot list */
1049 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1050         __le32  s_error_count;          /* number of fs errors */
1051         __le32  s_first_error_time;     /* first time an error happened */
1052         __le32  s_first_error_ino;      /* inode involved in first error */
1053         __le64  s_first_error_block;    /* block involved of first error */
1054         __u8    s_first_error_func[32]; /* function where the error happened */
1055         __le32  s_first_error_line;     /* line number where error happened */
1056         __le32  s_last_error_time;      /* most recent time of an error */
1057         __le32  s_last_error_ino;       /* inode involved in last error */
1058         __le32  s_last_error_line;      /* line number where error happened */
1059         __le64  s_last_error_block;     /* block involved of last error */
1060         __u8    s_last_error_func[32];  /* function where the error happened */
1061 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1062         __u8    s_mount_opts[64];
1063         __le32  s_reserved[112];        /* Padding to the end of the block */
1064 };
1065
1066 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1067
1068 #ifdef __KERNEL__
1069
1070 /*
1071  * run-time mount flags
1072  */
1073 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1074 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1075
1076 /*
1077  * fourth extended-fs super-block data in memory
1078  */
1079 struct ext4_sb_info {
1080         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1081         unsigned long s_inodes_per_block;/* Number of inodes per block */
1082         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1083         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1084         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1085         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1086         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1087         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1088         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1089         unsigned long s_overhead_last;  /* Last calculated overhead */
1090         unsigned long s_blocks_last;    /* Last seen block count */
1091         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1092         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1093         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1094         struct buffer_head **s_group_desc;
1095         unsigned int s_mount_opt;
1096         unsigned int s_mount_opt2;
1097         unsigned int s_mount_flags;
1098         ext4_fsblk_t s_sb_block;
1099         uid_t s_resuid;
1100         gid_t s_resgid;
1101         unsigned short s_mount_state;
1102         unsigned short s_pad;
1103         int s_addr_per_block_bits;
1104         int s_desc_per_block_bits;
1105         int s_inode_size;
1106         int s_first_ino;
1107         unsigned int s_inode_readahead_blks;
1108         unsigned int s_inode_goal;
1109         spinlock_t s_next_gen_lock;
1110         u32 s_next_generation;
1111         u32 s_hash_seed[4];
1112         int s_def_hash_version;
1113         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1114         struct percpu_counter s_freeblocks_counter;
1115         struct percpu_counter s_freeinodes_counter;
1116         struct percpu_counter s_dirs_counter;
1117         struct percpu_counter s_dirtyblocks_counter;
1118         struct blockgroup_lock *s_blockgroup_lock;
1119         struct proc_dir_entry *s_proc;
1120         struct kobject s_kobj;
1121         struct completion s_kobj_unregister;
1122
1123         /* Journaling */
1124         struct journal_s *s_journal;
1125         struct list_head s_orphan;
1126         struct mutex s_orphan_lock;
1127         struct mutex s_resize_lock;
1128         unsigned long s_commit_interval;
1129         u32 s_max_batch_time;
1130         u32 s_min_batch_time;
1131         struct block_device *journal_bdev;
1132 #ifdef CONFIG_JBD2_DEBUG
1133         struct timer_list turn_ro_timer;        /* For turning read-only (crash simulation) */
1134         wait_queue_head_t ro_wait_queue;        /* For people waiting for the fs to go read-only */
1135 #endif
1136 #ifdef CONFIG_QUOTA
1137         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1138         int s_jquota_fmt;                       /* Format of quota to use */
1139 #endif
1140         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1141         struct rb_root system_blks;
1142
1143 #ifdef EXTENTS_STATS
1144         /* ext4 extents stats */
1145         unsigned long s_ext_min;
1146         unsigned long s_ext_max;
1147         unsigned long s_depth_max;
1148         spinlock_t s_ext_stats_lock;
1149         unsigned long s_ext_blocks;
1150         unsigned long s_ext_extents;
1151 #endif
1152         /* ext4 extent cache stats */
1153         unsigned long extent_cache_hits;
1154         unsigned long extent_cache_misses;
1155
1156         /* for buddy allocator */
1157         struct ext4_group_info ***s_group_info;
1158         struct inode *s_buddy_cache;
1159         spinlock_t s_md_lock;
1160         unsigned short *s_mb_offsets;
1161         unsigned int *s_mb_maxs;
1162
1163         /* tunables */
1164         unsigned long s_stripe;
1165         unsigned int s_mb_stream_request;
1166         unsigned int s_mb_max_to_scan;
1167         unsigned int s_mb_min_to_scan;
1168         unsigned int s_mb_stats;
1169         unsigned int s_mb_order2_reqs;
1170         unsigned int s_mb_group_prealloc;
1171         unsigned int s_max_writeback_mb_bump;
1172         /* where last allocation was done - for stream allocation */
1173         unsigned long s_mb_last_group;
1174         unsigned long s_mb_last_start;
1175
1176         /* stats for buddy allocator */
1177         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1178         atomic_t s_bal_success; /* we found long enough chunks */
1179         atomic_t s_bal_allocated;       /* in blocks */
1180         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1181         atomic_t s_bal_goals;   /* goal hits */
1182         atomic_t s_bal_breaks;  /* too long searches */
1183         atomic_t s_bal_2orders; /* 2^order hits */
1184         spinlock_t s_bal_lock;
1185         unsigned long s_mb_buddies_generated;
1186         unsigned long long s_mb_generation_time;
1187         atomic_t s_mb_lost_chunks;
1188         atomic_t s_mb_preallocated;
1189         atomic_t s_mb_discarded;
1190         atomic_t s_lock_busy;
1191
1192         /* locality groups */
1193         struct ext4_locality_group __percpu *s_locality_groups;
1194
1195         /* for write statistics */
1196         unsigned long s_sectors_written_start;
1197         u64 s_kbytes_written;
1198
1199         unsigned int s_log_groups_per_flex;
1200         struct flex_groups *s_flex_groups;
1201
1202         /* workqueue for dio unwritten */
1203         struct workqueue_struct *dio_unwritten_wq;
1204
1205         /* timer for periodic error stats printing */
1206         struct timer_list s_err_report;
1207
1208         /* Lazy inode table initialization info */
1209         struct ext4_li_request *s_li_request;
1210         /* Wait multiplier for lazy initialization thread */
1211         unsigned int s_li_wait_mult;
1212
1213         /* Kernel thread for multiple mount protection */
1214         struct task_struct *s_mmp_tsk;
1215 };
1216
1217 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1218 {
1219         return sb->s_fs_info;
1220 }
1221 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1222 {
1223         return container_of(inode, struct ext4_inode_info, vfs_inode);
1224 }
1225
1226 static inline struct timespec ext4_current_time(struct inode *inode)
1227 {
1228         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1229                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1230 }
1231
1232 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1233 {
1234         return ino == EXT4_ROOT_INO ||
1235                 ino == EXT4_JOURNAL_INO ||
1236                 ino == EXT4_RESIZE_INO ||
1237                 (ino >= EXT4_FIRST_INO(sb) &&
1238                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1239 }
1240
1241 /*
1242  * Inode dynamic state flags
1243  */
1244 enum {
1245         EXT4_STATE_JDATA,               /* journaled data exists */
1246         EXT4_STATE_NEW,                 /* inode is newly created */
1247         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1248         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1249         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1250         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1251         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1252         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1253         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1254 };
1255
1256 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1257 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1258 {                                                                       \
1259         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1260 }                                                                       \
1261 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1262 {                                                                       \
1263         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1264 }                                                                       \
1265 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1266 {                                                                       \
1267         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1268 }
1269
1270 EXT4_INODE_BIT_FNS(flag, flags, 0)
1271 #if (BITS_PER_LONG < 64)
1272 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1273
1274 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1275 {
1276         (ei)->i_state_flags = 0;
1277 }
1278 #else
1279 EXT4_INODE_BIT_FNS(state, flags, 32)
1280
1281 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1282 {
1283         /* We depend on the fact that callers will set i_flags */
1284 }
1285 #endif
1286 #else
1287 /* Assume that user mode programs are passing in an ext4fs superblock, not
1288  * a kernel struct super_block.  This will allow us to call the feature-test
1289  * macros from user land. */
1290 #define EXT4_SB(sb)     (sb)
1291 #endif
1292
1293 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1294
1295 /*
1296  * Codes for operating systems
1297  */
1298 #define EXT4_OS_LINUX           0
1299 #define EXT4_OS_HURD            1
1300 #define EXT4_OS_MASIX           2
1301 #define EXT4_OS_FREEBSD         3
1302 #define EXT4_OS_LITES           4
1303
1304 /*
1305  * Revision levels
1306  */
1307 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1308 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1309
1310 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1311 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1312
1313 #define EXT4_GOOD_OLD_INODE_SIZE 128
1314
1315 /*
1316  * Feature set definitions
1317  */
1318
1319 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1320         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1321 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1322         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1323 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1324         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1325 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1326         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1327 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1328         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1329 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1330         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1331 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1332         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1333 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1334         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1335 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1336         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1337
1338 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1339 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1340 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1341 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1342 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1343 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1344
1345 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1346 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1347 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1348 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1349 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1350 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1351 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1352 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1353
1354 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1355 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1356 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1357 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1358 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1359 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1360 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1361 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1362 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1363 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1364 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1365
1366 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1367 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1368                                          EXT4_FEATURE_INCOMPAT_META_BG)
1369 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1370                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1371                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1372
1373 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1374 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1375                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1376                                          EXT4_FEATURE_INCOMPAT_META_BG)
1377 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1378                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1379                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1380
1381 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1382 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1383                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1384                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1385                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1386                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1387                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1388                                          EXT4_FEATURE_INCOMPAT_MMP)
1389 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1390                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1391                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1392                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1393                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1394                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1395                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1396
1397 /*
1398  * Default values for user and/or group using reserved blocks
1399  */
1400 #define EXT4_DEF_RESUID         0
1401 #define EXT4_DEF_RESGID         0
1402
1403 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1404
1405 /*
1406  * Default mount options
1407  */
1408 #define EXT4_DEFM_DEBUG         0x0001
1409 #define EXT4_DEFM_BSDGROUPS     0x0002
1410 #define EXT4_DEFM_XATTR_USER    0x0004
1411 #define EXT4_DEFM_ACL           0x0008
1412 #define EXT4_DEFM_UID16         0x0010
1413 #define EXT4_DEFM_JMODE         0x0060
1414 #define EXT4_DEFM_JMODE_DATA    0x0020
1415 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1416 #define EXT4_DEFM_JMODE_WBACK   0x0060
1417 #define EXT4_DEFM_NOBARRIER     0x0100
1418 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1419 #define EXT4_DEFM_DISCARD       0x0400
1420 #define EXT4_DEFM_NODELALLOC    0x0800
1421
1422 /*
1423  * Default journal batch times
1424  */
1425 #define EXT4_DEF_MIN_BATCH_TIME 0
1426 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1427
1428 /*
1429  * Minimum number of groups in a flexgroup before we separate out
1430  * directories into the first block group of a flexgroup
1431  */
1432 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1433
1434 /*
1435  * Structure of a directory entry
1436  */
1437 #define EXT4_NAME_LEN 255
1438
1439 struct ext4_dir_entry {
1440         __le32  inode;                  /* Inode number */
1441         __le16  rec_len;                /* Directory entry length */
1442         __le16  name_len;               /* Name length */
1443         char    name[EXT4_NAME_LEN];    /* File name */
1444 };
1445
1446 /*
1447  * The new version of the directory entry.  Since EXT4 structures are
1448  * stored in intel byte order, and the name_len field could never be
1449  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1450  * file_type field.
1451  */
1452 struct ext4_dir_entry_2 {
1453         __le32  inode;                  /* Inode number */
1454         __le16  rec_len;                /* Directory entry length */
1455         __u8    name_len;               /* Name length */
1456         __u8    file_type;
1457         char    name[EXT4_NAME_LEN];    /* File name */
1458 };
1459
1460 /*
1461  * Ext4 directory file types.  Only the low 3 bits are used.  The
1462  * other bits are reserved for now.
1463  */
1464 #define EXT4_FT_UNKNOWN         0
1465 #define EXT4_FT_REG_FILE        1
1466 #define EXT4_FT_DIR             2
1467 #define EXT4_FT_CHRDEV          3
1468 #define EXT4_FT_BLKDEV          4
1469 #define EXT4_FT_FIFO            5
1470 #define EXT4_FT_SOCK            6
1471 #define EXT4_FT_SYMLINK         7
1472
1473 #define EXT4_FT_MAX             8
1474
1475 /*
1476  * EXT4_DIR_PAD defines the directory entries boundaries
1477  *
1478  * NOTE: It must be a multiple of 4
1479  */
1480 #define EXT4_DIR_PAD                    4
1481 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1482 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1483                                          ~EXT4_DIR_ROUND)
1484 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1485
1486 /*
1487  * If we ever get support for fs block sizes > page_size, we'll need
1488  * to remove the #if statements in the next two functions...
1489  */
1490 static inline unsigned int
1491 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1492 {
1493         unsigned len = le16_to_cpu(dlen);
1494
1495 #if (PAGE_CACHE_SIZE >= 65536)
1496         if (len == EXT4_MAX_REC_LEN || len == 0)
1497                 return blocksize;
1498         return (len & 65532) | ((len & 3) << 16);
1499 #else
1500         return len;
1501 #endif
1502 }
1503
1504 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1505 {
1506         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1507                 BUG();
1508 #if (PAGE_CACHE_SIZE >= 65536)
1509         if (len < 65536)
1510                 return cpu_to_le16(len);
1511         if (len == blocksize) {
1512                 if (blocksize == 65536)
1513                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1514                 else
1515                         return cpu_to_le16(0);
1516         }
1517         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1518 #else
1519         return cpu_to_le16(len);
1520 #endif
1521 }
1522
1523 /*
1524  * Hash Tree Directory indexing
1525  * (c) Daniel Phillips, 2001
1526  */
1527
1528 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1529                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1530                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1531 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1532 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1533
1534 /* Legal values for the dx_root hash_version field: */
1535
1536 #define DX_HASH_LEGACY          0
1537 #define DX_HASH_HALF_MD4        1
1538 #define DX_HASH_TEA             2
1539 #define DX_HASH_LEGACY_UNSIGNED 3
1540 #define DX_HASH_HALF_MD4_UNSIGNED       4
1541 #define DX_HASH_TEA_UNSIGNED            5
1542
1543 #ifdef __KERNEL__
1544
1545 /* hash info structure used by the directory hash */
1546 struct dx_hash_info
1547 {
1548         u32             hash;
1549         u32             minor_hash;
1550         int             hash_version;
1551         u32             *seed;
1552 };
1553
1554 #define EXT4_HTREE_EOF  0x7fffffff
1555
1556 /*
1557  * Control parameters used by ext4_htree_next_block
1558  */
1559 #define HASH_NB_ALWAYS          1
1560
1561
1562 /*
1563  * Describe an inode's exact location on disk and in memory
1564  */
1565 struct ext4_iloc
1566 {
1567         struct buffer_head *bh;
1568         unsigned long offset;
1569         ext4_group_t block_group;
1570 };
1571
1572 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1573 {
1574         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1575 }
1576
1577 /*
1578  * This structure is stuffed into the struct file's private_data field
1579  * for directories.  It is where we put information so that we can do
1580  * readdir operations in hash tree order.
1581  */
1582 struct dir_private_info {
1583         struct rb_root  root;
1584         struct rb_node  *curr_node;
1585         struct fname    *extra_fname;
1586         loff_t          last_pos;
1587         __u32           curr_hash;
1588         __u32           curr_minor_hash;
1589         __u32           next_hash;
1590 };
1591
1592 /* calculate the first block number of the group */
1593 static inline ext4_fsblk_t
1594 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1595 {
1596         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1597                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1598 }
1599
1600 /*
1601  * Special error return code only used by dx_probe() and its callers.
1602  */
1603 #define ERR_BAD_DX_DIR  -75000
1604
1605 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1606                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1607
1608 /*
1609  * Timeout and state flag for lazy initialization inode thread.
1610  */
1611 #define EXT4_DEF_LI_WAIT_MULT                   10
1612 #define EXT4_DEF_LI_MAX_START_DELAY             5
1613 #define EXT4_LAZYINIT_QUIT                      0x0001
1614 #define EXT4_LAZYINIT_RUNNING                   0x0002
1615
1616 /*
1617  * Lazy inode table initialization info
1618  */
1619 struct ext4_lazy_init {
1620         unsigned long           li_state;
1621         struct list_head        li_request_list;
1622         struct mutex            li_list_mtx;
1623 };
1624
1625 struct ext4_li_request {
1626         struct super_block      *lr_super;
1627         struct ext4_sb_info     *lr_sbi;
1628         ext4_group_t            lr_next_group;
1629         struct list_head        lr_request;
1630         unsigned long           lr_next_sched;
1631         unsigned long           lr_timeout;
1632 };
1633
1634 struct ext4_features {
1635         struct kobject f_kobj;
1636         struct completion f_kobj_unregister;
1637 };
1638
1639 /*
1640  * This structure will be used for multiple mount protection. It will be
1641  * written into the block number saved in the s_mmp_block field in the
1642  * superblock. Programs that check MMP should assume that if
1643  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1644  * to use the filesystem, regardless of how old the timestamp is.
1645  */
1646 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1647 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1648 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1649 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1650
1651 struct mmp_struct {
1652         __le32  mmp_magic;              /* Magic number for MMP */
1653         __le32  mmp_seq;                /* Sequence no. updated periodically */
1654
1655         /*
1656          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1657          * purposes and do not affect the correctness of the algorithm
1658          */
1659         __le64  mmp_time;               /* Time last updated */
1660         char    mmp_nodename[64];       /* Node which last updated MMP block */
1661         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1662
1663         /*
1664          * mmp_check_interval is used to verify if the MMP block has been
1665          * updated on the block device. The value is updated based on the
1666          * maximum time to write the MMP block during an update cycle.
1667          */
1668         __le16  mmp_check_interval;
1669
1670         __le16  mmp_pad1;
1671         __le32  mmp_pad2[227];
1672 };
1673
1674 /* arguments passed to the mmp thread */
1675 struct mmpd_data {
1676         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1677         struct super_block *sb;  /* super block of the fs */
1678 };
1679
1680 /*
1681  * Check interval multiplier
1682  * The MMP block is written every update interval and initially checked every
1683  * update interval x the multiplier (the value is then adapted based on the
1684  * write latency). The reason is that writes can be delayed under load and we
1685  * don't want readers to incorrectly assume that the filesystem is no longer
1686  * in use.
1687  */
1688 #define EXT4_MMP_CHECK_MULT             2UL
1689
1690 /*
1691  * Minimum interval for MMP checking in seconds.
1692  */
1693 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1694
1695 /*
1696  * Maximum interval for MMP checking in seconds.
1697  */
1698 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1699
1700 /*
1701  * Function prototypes
1702  */
1703
1704 /*
1705  * Ok, these declarations are also in <linux/kernel.h> but none of the
1706  * ext4 source programs needs to include it so they are duplicated here.
1707  */
1708 # define NORET_TYPE     /**/
1709 # define ATTRIB_NORET   __attribute__((noreturn))
1710 # define NORET_AND      noreturn,
1711
1712 /* bitmap.c */
1713 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1714
1715 /* balloc.c */
1716 extern unsigned int ext4_block_group(struct super_block *sb,
1717                         ext4_fsblk_t blocknr);
1718 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1719                         ext4_fsblk_t blocknr);
1720 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1721 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1722                         ext4_group_t group);
1723 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1724                                          ext4_fsblk_t goal,
1725                                          unsigned int flags,
1726                                          unsigned long *count,
1727                                          int *errp);
1728 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
1729                                   s64 nblocks, unsigned int flags);
1730 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1731 extern void ext4_check_blocks_bitmap(struct super_block *);
1732 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1733                                                     ext4_group_t block_group,
1734                                                     struct buffer_head ** bh);
1735 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1736 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1737                                       ext4_group_t block_group);
1738 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1739                                        struct buffer_head *bh,
1740                                        ext4_group_t group,
1741                                        struct ext4_group_desc *desc);
1742 #define ext4_free_blocks_after_init(sb, group, desc)                    \
1743                 ext4_init_block_bitmap(sb, NULL, group, desc)
1744
1745 /* dir.c */
1746 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1747                                   struct file *,
1748                                   struct ext4_dir_entry_2 *,
1749                                   struct buffer_head *, unsigned int);
1750 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1751         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1752                                         (de), (bh), (offset)))
1753 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1754                                     __u32 minor_hash,
1755                                     struct ext4_dir_entry_2 *dirent);
1756 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1757
1758 /* fsync.c */
1759 extern int ext4_sync_file(struct file *, int);
1760 extern int ext4_flush_completed_IO(struct inode *);
1761
1762 /* hash.c */
1763 extern int ext4fs_dirhash(const char *name, int len, struct
1764                           dx_hash_info *hinfo);
1765
1766 /* ialloc.c */
1767 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1768                                     const struct qstr *qstr, __u32 goal);
1769 extern void ext4_free_inode(handle_t *, struct inode *);
1770 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1771 extern unsigned long ext4_count_free_inodes(struct super_block *);
1772 extern unsigned long ext4_count_dirs(struct super_block *);
1773 extern void ext4_check_inodes_bitmap(struct super_block *);
1774 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1775 extern int ext4_init_inode_table(struct super_block *sb,
1776                                  ext4_group_t group, int barrier);
1777
1778 /* mballoc.c */
1779 extern long ext4_mb_stats;
1780 extern long ext4_mb_max_to_scan;
1781 extern int ext4_mb_init(struct super_block *, int);
1782 extern int ext4_mb_release(struct super_block *);
1783 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1784                                 struct ext4_allocation_request *, int *);
1785 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1786 extern void ext4_discard_preallocations(struct inode *);
1787 extern int __init ext4_init_mballoc(void);
1788 extern void ext4_exit_mballoc(void);
1789 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1790                              struct buffer_head *bh, ext4_fsblk_t block,
1791                              unsigned long count, int flags);
1792 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1793                 ext4_group_t i, struct ext4_group_desc *desc);
1794 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1795                                 ext4_fsblk_t block, unsigned long count);
1796 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1797
1798 /* inode.c */
1799 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1800                                                 ext4_lblk_t, int, int *);
1801 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1802                                                 ext4_lblk_t, int, int *);
1803 int ext4_get_block(struct inode *inode, sector_t iblock,
1804                                 struct buffer_head *bh_result, int create);
1805
1806 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1807 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1808 extern int  ext4_setattr(struct dentry *, struct iattr *);
1809 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1810                                 struct kstat *stat);
1811 extern void ext4_evict_inode(struct inode *);
1812 extern void ext4_clear_inode(struct inode *);
1813 extern int  ext4_sync_inode(handle_t *, struct inode *);
1814 extern void ext4_dirty_inode(struct inode *);
1815 extern int ext4_change_inode_journal_flag(struct inode *, int);
1816 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1817 extern int ext4_can_truncate(struct inode *inode);
1818 extern void ext4_truncate(struct inode *);
1819 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1820 extern void ext4_set_inode_flags(struct inode *);
1821 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1822 extern int ext4_alloc_da_blocks(struct inode *inode);
1823 extern void ext4_set_aops(struct inode *inode);
1824 extern int ext4_writepage_trans_blocks(struct inode *);
1825 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1826 extern int ext4_block_truncate_page(handle_t *handle,
1827                 struct address_space *mapping, loff_t from);
1828 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1829 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1830 extern void ext4_da_update_reserve_space(struct inode *inode,
1831                                         int used, int quota_claim);
1832 /* ioctl.c */
1833 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1834 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1835
1836 /* migrate.c */
1837 extern int ext4_ext_migrate(struct inode *);
1838
1839 /* namei.c */
1840 extern int ext4_orphan_add(handle_t *, struct inode *);
1841 extern int ext4_orphan_del(handle_t *, struct inode *);
1842 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1843                                 __u32 start_minor_hash, __u32 *next_hash);
1844
1845 /* resize.c */
1846 extern int ext4_group_add(struct super_block *sb,
1847                                 struct ext4_new_group_data *input);
1848 extern int ext4_group_extend(struct super_block *sb,
1849                                 struct ext4_super_block *es,
1850                                 ext4_fsblk_t n_blocks_count);
1851
1852 /* super.c */
1853 extern void __ext4_error(struct super_block *, const char *, unsigned int,
1854                          const char *, ...)
1855         __attribute__ ((format (printf, 4, 5)));
1856 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
1857                                                      __LINE__, ## message)
1858 extern void ext4_error_inode(struct inode *, const char *, unsigned int,
1859                              ext4_fsblk_t, const char *, ...)
1860         __attribute__ ((format (printf, 5, 6)));
1861 extern void ext4_error_file(struct file *, const char *, unsigned int,
1862                             ext4_fsblk_t, const char *, ...)
1863         __attribute__ ((format (printf, 5, 6)));
1864 extern void __ext4_std_error(struct super_block *, const char *,
1865                              unsigned int, int);
1866 extern void __ext4_abort(struct super_block *, const char *, unsigned int,
1867                        const char *, ...)
1868         __attribute__ ((format (printf, 4, 5)));
1869 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
1870                                                        __LINE__, ## message)
1871 extern void __ext4_warning(struct super_block *, const char *, unsigned int,
1872                           const char *, ...)
1873         __attribute__ ((format (printf, 4, 5)));
1874 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
1875                                                        __LINE__, ## message)
1876 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1877         __attribute__ ((format (printf, 3, 4)));
1878 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
1879                            const char *, unsigned int, const char *);
1880 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
1881                                                        __LINE__, msg)
1882 extern void __ext4_grp_locked_error(const char *, unsigned int, \
1883                                     struct super_block *, ext4_group_t, \
1884                                     unsigned long, ext4_fsblk_t, \
1885                                     const char *, ...)
1886         __attribute__ ((format (printf, 7, 8)));
1887 #define ext4_grp_locked_error(sb, grp, message...) \
1888         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1889 extern void ext4_update_dynamic_rev(struct super_block *sb);
1890 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1891                                         __u32 compat);
1892 extern int ext4_update_rocompat_feature(handle_t *handle,
1893                                         struct super_block *sb, __u32 rocompat);
1894 extern int ext4_update_incompat_feature(handle_t *handle,
1895                                         struct super_block *sb, __u32 incompat);
1896 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1897                                       struct ext4_group_desc *bg);
1898 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1899                                       struct ext4_group_desc *bg);
1900 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1901                                      struct ext4_group_desc *bg);
1902 extern __u32 ext4_free_blks_count(struct super_block *sb,
1903                                 struct ext4_group_desc *bg);
1904 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1905                                  struct ext4_group_desc *bg);
1906 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1907                                 struct ext4_group_desc *bg);
1908 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1909                                    struct ext4_group_desc *bg);
1910 extern void ext4_block_bitmap_set(struct super_block *sb,
1911                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1912 extern void ext4_inode_bitmap_set(struct super_block *sb,
1913                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1914 extern void ext4_inode_table_set(struct super_block *sb,
1915                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1916 extern void ext4_free_blks_set(struct super_block *sb,
1917                                struct ext4_group_desc *bg, __u32 count);
1918 extern void ext4_free_inodes_set(struct super_block *sb,
1919                                 struct ext4_group_desc *bg, __u32 count);
1920 extern void ext4_used_dirs_set(struct super_block *sb,
1921                                 struct ext4_group_desc *bg, __u32 count);
1922 extern void ext4_itable_unused_set(struct super_block *sb,
1923                                    struct ext4_group_desc *bg, __u32 count);
1924 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1925                                    struct ext4_group_desc *gdp);
1926 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1927                                        struct ext4_group_desc *gdp);
1928
1929 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1930 {
1931         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1932                 le32_to_cpu(es->s_blocks_count_lo);
1933 }
1934
1935 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1936 {
1937         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1938                 le32_to_cpu(es->s_r_blocks_count_lo);
1939 }
1940
1941 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1942 {
1943         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1944                 le32_to_cpu(es->s_free_blocks_count_lo);
1945 }
1946
1947 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1948                                          ext4_fsblk_t blk)
1949 {
1950         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1951         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1952 }
1953
1954 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1955                                               ext4_fsblk_t blk)
1956 {
1957         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1958         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1959 }
1960
1961 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1962                                            ext4_fsblk_t blk)
1963 {
1964         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1965         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1966 }
1967
1968 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1969 {
1970         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1971                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1972                         le32_to_cpu(raw_inode->i_size_lo);
1973         else
1974                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1975 }
1976
1977 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1978 {
1979         raw_inode->i_size_lo = cpu_to_le32(i_size);
1980         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1981 }
1982
1983 static inline
1984 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1985                                             ext4_group_t group)
1986 {
1987          struct ext4_group_info ***grp_info;
1988          long indexv, indexh;
1989          grp_info = EXT4_SB(sb)->s_group_info;
1990          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1991          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1992          return grp_info[indexv][indexh];
1993 }
1994
1995 /*
1996  * Reading s_groups_count requires using smp_rmb() afterwards.  See
1997  * the locking protocol documented in the comments of ext4_group_add()
1998  * in resize.c
1999  */
2000 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2001 {
2002         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2003
2004         smp_rmb();
2005         return ngroups;
2006 }
2007
2008 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2009                                              ext4_group_t block_group)
2010 {
2011         return block_group >> sbi->s_log_groups_per_flex;
2012 }
2013
2014 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2015 {
2016         return 1 << sbi->s_log_groups_per_flex;
2017 }
2018
2019 #define ext4_std_error(sb, errno)                               \
2020 do {                                                            \
2021         if ((errno))                                            \
2022                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2023 } while (0)
2024
2025 #ifdef CONFIG_SMP
2026 /* Each CPU can accumulate percpu_counter_batch blocks in their local
2027  * counters. So we need to make sure we have free blocks more
2028  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2029  */
2030 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2031 #else
2032 #define EXT4_FREEBLOCKS_WATERMARK 0
2033 #endif
2034
2035 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2036 {
2037         /*
2038          * XXX: replace with spinlock if seen contended -bzzz
2039          */
2040         down_write(&EXT4_I(inode)->i_data_sem);
2041         if (newsize > EXT4_I(inode)->i_disksize)
2042                 EXT4_I(inode)->i_disksize = newsize;
2043         up_write(&EXT4_I(inode)->i_data_sem);
2044         return ;
2045 }
2046
2047 struct ext4_group_info {
2048         unsigned long   bb_state;
2049         struct rb_root  bb_free_root;
2050         ext4_grpblk_t   bb_first_free;  /* first free block */
2051         ext4_grpblk_t   bb_free;        /* total free blocks */
2052         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2053         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2054         struct          list_head bb_prealloc_list;
2055 #ifdef DOUBLE_CHECK
2056         void            *bb_bitmap;
2057 #endif
2058         struct rw_semaphore alloc_sem;
2059         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2060                                          * regions, index is order.
2061                                          * bb_counters[3] = 5 means
2062                                          * 5 free 8-block regions. */
2063 };
2064
2065 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
2066
2067 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2068         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2069
2070 #define EXT4_MAX_CONTENTION             8
2071 #define EXT4_CONTENTION_THRESHOLD       2
2072
2073 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2074                                               ext4_group_t group)
2075 {
2076         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2077 }
2078
2079 /*
2080  * Returns true if the filesystem is busy enough that attempts to
2081  * access the block group locks has run into contention.
2082  */
2083 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2084 {
2085         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2086 }
2087
2088 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2089 {
2090         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2091         if (spin_trylock(lock))
2092                 /*
2093                  * We're able to grab the lock right away, so drop the
2094                  * lock contention counter.
2095                  */
2096                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2097         else {
2098                 /*
2099                  * The lock is busy, so bump the contention counter,
2100                  * and then wait on the spin lock.
2101                  */
2102                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2103                                   EXT4_MAX_CONTENTION);
2104                 spin_lock(lock);
2105         }
2106 }
2107
2108 static inline void ext4_unlock_group(struct super_block *sb,
2109                                         ext4_group_t group)
2110 {
2111         spin_unlock(ext4_group_lock_ptr(sb, group));
2112 }
2113
2114 static inline void ext4_mark_super_dirty(struct super_block *sb)
2115 {
2116         if (EXT4_SB(sb)->s_journal == NULL)
2117                 sb->s_dirt =1;
2118 }
2119
2120 /*
2121  * Inodes and files operations
2122  */
2123
2124 /* dir.c */
2125 extern const struct file_operations ext4_dir_operations;
2126
2127 /* file.c */
2128 extern const struct inode_operations ext4_file_inode_operations;
2129 extern const struct file_operations ext4_file_operations;
2130 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2131
2132 /* namei.c */
2133 extern const struct inode_operations ext4_dir_inode_operations;
2134 extern const struct inode_operations ext4_special_inode_operations;
2135 extern struct dentry *ext4_get_parent(struct dentry *child);
2136
2137 /* symlink.c */
2138 extern const struct inode_operations ext4_symlink_inode_operations;
2139 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2140
2141 /* block_validity */
2142 extern void ext4_release_system_zone(struct super_block *sb);
2143 extern int ext4_setup_system_zone(struct super_block *sb);
2144 extern int __init ext4_init_system_zone(void);
2145 extern void ext4_exit_system_zone(void);
2146 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2147                                  ext4_fsblk_t start_blk,
2148                                  unsigned int count);
2149
2150 /* extents.c */
2151 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2152 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2153 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2154                                        int chunk);
2155 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2156                                struct ext4_map_blocks *map, int flags);
2157 extern void ext4_ext_truncate(struct inode *);
2158 extern void ext4_ext_init(struct super_block *);
2159 extern void ext4_ext_release(struct super_block *);
2160 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2161                           loff_t len);
2162 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2163                           ssize_t len);
2164 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2165                            struct ext4_map_blocks *map, int flags);
2166 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2167                         __u64 start, __u64 len);
2168 /* move_extent.c */
2169 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2170                              __u64 start_orig, __u64 start_donor,
2171                              __u64 len, __u64 *moved_len);
2172
2173 /* page-io.c */
2174 extern int __init ext4_init_pageio(void);
2175 extern void ext4_exit_pageio(void);
2176 extern void ext4_ioend_wait(struct inode *);
2177 extern void ext4_free_io_end(ext4_io_end_t *io);
2178 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2179 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2180 extern void ext4_io_submit(struct ext4_io_submit *io);
2181 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2182                                struct page *page,
2183                                int len,
2184                                struct writeback_control *wbc);
2185
2186 /* mmp.c */
2187 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2188
2189 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2190 enum ext4_state_bits {
2191         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2192           = BH_JBDPrivateStart,
2193 };
2194
2195 BUFFER_FNS(Uninit, uninit)
2196 TAS_BUFFER_FNS(Uninit, uninit)
2197
2198 /*
2199  * Add new method to test wether block and inode bitmaps are properly
2200  * initialized. With uninit_bg reading the block from disk is not enough
2201  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2202  */
2203 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2204
2205 static inline int bitmap_uptodate(struct buffer_head *bh)
2206 {
2207         return (buffer_uptodate(bh) &&
2208                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2209 }
2210 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2211 {
2212         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2213 }
2214
2215 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2216
2217 /* For ioend & aio unwritten conversion wait queues */
2218 #define EXT4_WQ_HASH_SZ         37
2219 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2220                                             EXT4_WQ_HASH_SZ])
2221 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2222                                              EXT4_WQ_HASH_SZ])
2223 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2224 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2225
2226 #endif  /* __KERNEL__ */
2227
2228 #endif  /* _EXT4_H */