ext4: use ext4_get_block_write in buffer write
[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
33 /*
34  * The fourth extended filesystem constants/structures
35  */
36
37 /*
38  * Define EXT4FS_DEBUG to produce debug messages
39  */
40 #undef EXT4FS_DEBUG
41
42 /*
43  * Debug code
44  */
45 #ifdef EXT4FS_DEBUG
46 #define ext4_debug(f, a...)                                             \
47         do {                                                            \
48                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
49                         __FILE__, __LINE__, __func__);                  \
50                 printk(KERN_DEBUG f, ## a);                             \
51         } while (0)
52 #else
53 #define ext4_debug(f, a...)     do {} while (0)
54 #endif
55
56 /* data type for block offset of block group */
57 typedef int ext4_grpblk_t;
58
59 /* data type for filesystem-wide blocks number */
60 typedef unsigned long long ext4_fsblk_t;
61
62 /* data type for file logical block number */
63 typedef __u32 ext4_lblk_t;
64
65 /* data type for block group number */
66 typedef unsigned int ext4_group_t;
67
68 /*
69  * Flags used in mballoc's allocation_context flags field.  
70  *
71  * Also used to show what's going on for debugging purposes when the
72  * flag field is exported via the traceport interface
73  */
74
75 /* prefer goal again. length */
76 #define EXT4_MB_HINT_MERGE              0x0001
77 /* blocks already reserved */
78 #define EXT4_MB_HINT_RESERVED           0x0002
79 /* metadata is being allocated */
80 #define EXT4_MB_HINT_METADATA           0x0004
81 /* first blocks in the file */
82 #define EXT4_MB_HINT_FIRST              0x0008
83 /* search for the best chunk */
84 #define EXT4_MB_HINT_BEST               0x0010
85 /* data is being allocated */
86 #define EXT4_MB_HINT_DATA               0x0020
87 /* don't preallocate (for tails) */
88 #define EXT4_MB_HINT_NOPREALLOC         0x0040
89 /* allocate for locality group */
90 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
91 /* allocate goal blocks or none */
92 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
93 /* goal is meaningful */
94 #define EXT4_MB_HINT_TRY_GOAL           0x0200
95 /* blocks already pre-reserved by delayed allocation */
96 #define EXT4_MB_DELALLOC_RESERVED       0x0400
97 /* We are doing stream allocation */
98 #define EXT4_MB_STREAM_ALLOC            0x0800
99
100
101 struct ext4_allocation_request {
102         /* target inode for block we're allocating */
103         struct inode *inode;
104         /* how many blocks we want to allocate */
105         unsigned int len;
106         /* logical block in target inode */
107         ext4_lblk_t logical;
108         /* the closest logical allocated block to the left */
109         ext4_lblk_t lleft;
110         /* the closest logical allocated block to the right */
111         ext4_lblk_t lright;
112         /* phys. target (a hint) */
113         ext4_fsblk_t goal;
114         /* phys. block for the closest logical allocated block to the left */
115         ext4_fsblk_t pleft;
116         /* phys. block for the closest logical allocated block to the right */
117         ext4_fsblk_t pright;
118         /* flags. see above EXT4_MB_HINT_* */
119         unsigned int flags;
120 };
121
122 /*
123  * For delayed allocation tracking
124  */
125 struct mpage_da_data {
126         struct inode *inode;
127         sector_t b_blocknr;             /* start block number of extent */
128         size_t b_size;                  /* size of extent */
129         unsigned long b_state;          /* state of the extent */
130         unsigned long first_page, next_page;    /* extent of pages */
131         struct writeback_control *wbc;
132         int io_done;
133         int pages_written;
134         int retval;
135 };
136 #define EXT4_IO_UNWRITTEN       0x1
137 typedef struct ext4_io_end {
138         struct list_head        list;           /* per-file finished AIO list */
139         struct inode            *inode;         /* file being written to */
140         unsigned int            flag;           /* unwritten or not */
141         struct page             *page;          /* page struct for buffer write */
142         loff_t                  offset;         /* offset in the file */
143         ssize_t                 size;           /* size of the extent */
144         struct work_struct      work;           /* data work queue */
145 } ext4_io_end_t;
146
147 /*
148  * Special inodes numbers
149  */
150 #define EXT4_BAD_INO             1      /* Bad blocks inode */
151 #define EXT4_ROOT_INO            2      /* Root inode */
152 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
153 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
154 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
155 #define EXT4_JOURNAL_INO         8      /* Journal inode */
156
157 /* First non-reserved inode for old ext4 filesystems */
158 #define EXT4_GOOD_OLD_FIRST_INO 11
159
160 /*
161  * Maximal count of links to a file
162  */
163 #define EXT4_LINK_MAX           65000
164
165 /*
166  * Macro-instructions used to manage several block sizes
167  */
168 #define EXT4_MIN_BLOCK_SIZE             1024
169 #define EXT4_MAX_BLOCK_SIZE             65536
170 #define EXT4_MIN_BLOCK_LOG_SIZE         10
171 #ifdef __KERNEL__
172 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
173 #else
174 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
175 #endif
176 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
177 #ifdef __KERNEL__
178 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
179 #else
180 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
181 #endif
182 #ifdef __KERNEL__
183 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
184 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
185 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
186 #else
187 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
188                                  EXT4_GOOD_OLD_INODE_SIZE : \
189                                  (s)->s_inode_size)
190 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
191                                  EXT4_GOOD_OLD_FIRST_INO : \
192                                  (s)->s_first_ino)
193 #endif
194 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
195
196 /*
197  * Structure of a blocks group descriptor
198  */
199 struct ext4_group_desc
200 {
201         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
202         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
203         __le32  bg_inode_table_lo;      /* Inodes table block */
204         __le16  bg_free_blocks_count_lo;/* Free blocks count */
205         __le16  bg_free_inodes_count_lo;/* Free inodes count */
206         __le16  bg_used_dirs_count_lo;  /* Directories count */
207         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
208         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
209         __le16  bg_itable_unused_lo;    /* Unused inodes count */
210         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
211         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
212         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
213         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
214         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
215         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
216         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
217         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
218         __u32   bg_reserved2[3];
219 };
220
221 /*
222  * Structure of a flex block group info
223  */
224
225 struct flex_groups {
226         atomic_t free_inodes;
227         atomic_t free_blocks;
228         atomic_t used_dirs;
229 };
230
231 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
232 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
233 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
234
235 /*
236  * Macro-instructions used to manage group descriptors
237  */
238 #define EXT4_MIN_DESC_SIZE              32
239 #define EXT4_MIN_DESC_SIZE_64BIT        64
240 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
241 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
242 #ifdef __KERNEL__
243 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
244 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
245 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
246 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
247 #else
248 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
249 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
250 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
251 #endif
252
253 /*
254  * Constants relative to the data blocks
255  */
256 #define EXT4_NDIR_BLOCKS                12
257 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
258 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
259 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
260 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
261
262 /*
263  * Inode flags
264  */
265 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
266 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
267 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
268 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
269 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
270 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
271 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
272 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
273 /* Reserved for compression usage... */
274 #define EXT4_DIRTY_FL                   0x00000100
275 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
276 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
277 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
278 /* End compression flags --- maybe not all used */
279 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
280 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
281 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
282 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
283 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
284 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
285 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
286 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
287 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
288 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
289 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
290
291 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
292 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
293
294 /* Flags that should be inherited by new inodes from their parent. */
295 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
296                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
297                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
298                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
299                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
300
301 /* Flags that are appropriate for regular files (all but dir-specific ones). */
302 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
303
304 /* Flags that are appropriate for non-directories/regular files. */
305 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
306
307 /* Mask out flags that are inappropriate for the given type of inode. */
308 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
309 {
310         if (S_ISDIR(mode))
311                 return flags;
312         else if (S_ISREG(mode))
313                 return flags & EXT4_REG_FLMASK;
314         else
315                 return flags & EXT4_OTHER_FLMASK;
316 }
317
318 /* Used to pass group descriptor data when online resize is done */
319 struct ext4_new_group_input {
320         __u32 group;            /* Group number for this data */
321         __u64 block_bitmap;     /* Absolute block number of block bitmap */
322         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
323         __u64 inode_table;      /* Absolute block number of inode table start */
324         __u32 blocks_count;     /* Total number of blocks in this group */
325         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
326         __u16 unused;
327 };
328
329 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
330 struct ext4_new_group_data {
331         __u32 group;
332         __u64 block_bitmap;
333         __u64 inode_bitmap;
334         __u64 inode_table;
335         __u32 blocks_count;
336         __u16 reserved_blocks;
337         __u16 unused;
338         __u32 free_blocks_count;
339 };
340
341 /*
342  * Flags used by ext4_get_blocks()
343  */
344         /* Allocate any needed blocks and/or convert an unitialized
345            extent to be an initialized ext4 */
346 #define EXT4_GET_BLOCKS_CREATE                  0x0001
347         /* Request the creation of an unitialized extent */
348 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
349 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
350                                                  EXT4_GET_BLOCKS_CREATE)
351         /* Caller is from the delayed allocation writeout path,
352            so set the magic i_delalloc_reserve_flag after taking the 
353            inode allocation semaphore for */
354 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
355         /* caller is from the direct IO path, request to creation of an
356         unitialized extents if not allocated, split the uninitialized
357         extent if blocks has been preallocated already*/
358 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
359 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
360 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
361                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
362         /* Convert extent to initialized after IO complete */
363 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
364                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
365
366 /*
367  * Flags used by ext4_free_blocks
368  */
369 #define EXT4_FREE_BLOCKS_METADATA       0x0001
370 #define EXT4_FREE_BLOCKS_FORGET         0x0002
371 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
372
373 /*
374  * ioctl commands
375  */
376 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
377 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
378 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
379 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
380 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
381 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
382 #ifdef CONFIG_JBD2_DEBUG
383 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
384 #endif
385 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
386 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
387 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
388 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
389 #define EXT4_IOC_MIGRATE                _IO('f', 9)
390  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
391  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
392 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
393 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
394
395 /*
396  * ioctl commands in 32 bit emulation
397  */
398 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
399 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
400 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
401 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
402 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
403 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
404 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
405 #ifdef CONFIG_JBD2_DEBUG
406 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
407 #endif
408 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
409 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
410
411
412 /*
413  *  Mount options
414  */
415 struct ext4_mount_options {
416         unsigned long s_mount_opt;
417         uid_t s_resuid;
418         gid_t s_resgid;
419         unsigned long s_commit_interval;
420         u32 s_min_batch_time, s_max_batch_time;
421 #ifdef CONFIG_QUOTA
422         int s_jquota_fmt;
423         char *s_qf_names[MAXQUOTAS];
424 #endif
425 };
426
427 /* Max physical block we can addres w/o extents */
428 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
429
430 /*
431  * Structure of an inode on the disk
432  */
433 struct ext4_inode {
434         __le16  i_mode;         /* File mode */
435         __le16  i_uid;          /* Low 16 bits of Owner Uid */
436         __le32  i_size_lo;      /* Size in bytes */
437         __le32  i_atime;        /* Access time */
438         __le32  i_ctime;        /* Inode Change time */
439         __le32  i_mtime;        /* Modification time */
440         __le32  i_dtime;        /* Deletion Time */
441         __le16  i_gid;          /* Low 16 bits of Group Id */
442         __le16  i_links_count;  /* Links count */
443         __le32  i_blocks_lo;    /* Blocks count */
444         __le32  i_flags;        /* File flags */
445         union {
446                 struct {
447                         __le32  l_i_version;
448                 } linux1;
449                 struct {
450                         __u32  h_i_translator;
451                 } hurd1;
452                 struct {
453                         __u32  m_i_reserved1;
454                 } masix1;
455         } osd1;                         /* OS dependent 1 */
456         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
457         __le32  i_generation;   /* File version (for NFS) */
458         __le32  i_file_acl_lo;  /* File ACL */
459         __le32  i_size_high;
460         __le32  i_obso_faddr;   /* Obsoleted fragment address */
461         union {
462                 struct {
463                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
464                         __le16  l_i_file_acl_high;
465                         __le16  l_i_uid_high;   /* these 2 fields */
466                         __le16  l_i_gid_high;   /* were reserved2[0] */
467                         __u32   l_i_reserved2;
468                 } linux2;
469                 struct {
470                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
471                         __u16   h_i_mode_high;
472                         __u16   h_i_uid_high;
473                         __u16   h_i_gid_high;
474                         __u32   h_i_author;
475                 } hurd2;
476                 struct {
477                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
478                         __le16  m_i_file_acl_high;
479                         __u32   m_i_reserved2[2];
480                 } masix2;
481         } osd2;                         /* OS dependent 2 */
482         __le16  i_extra_isize;
483         __le16  i_pad1;
484         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
485         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
486         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
487         __le32  i_crtime;       /* File Creation time */
488         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
489         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
490 };
491
492 struct move_extent {
493         __u32 reserved;         /* should be zero */
494         __u32 donor_fd;         /* donor file descriptor */
495         __u64 orig_start;       /* logical start offset in block for orig */
496         __u64 donor_start;      /* logical start offset in block for donor */
497         __u64 len;              /* block length to be moved */
498         __u64 moved_len;        /* moved block length */
499 };
500
501 #define EXT4_EPOCH_BITS 2
502 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
503 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
504
505 /*
506  * Extended fields will fit into an inode if the filesystem was formatted
507  * with large inodes (-I 256 or larger) and there are not currently any EAs
508  * consuming all of the available space. For new inodes we always reserve
509  * enough space for the kernel's known extended fields, but for inodes
510  * created with an old kernel this might not have been the case. None of
511  * the extended inode fields is critical for correct filesystem operation.
512  * This macro checks if a certain field fits in the inode. Note that
513  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
514  */
515 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
516         ((offsetof(typeof(*ext4_inode), field) +        \
517           sizeof((ext4_inode)->field))                  \
518         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
519             (einode)->i_extra_isize))                   \
520
521 static inline __le32 ext4_encode_extra_time(struct timespec *time)
522 {
523        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
524                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
525                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
526 }
527
528 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
529 {
530        if (sizeof(time->tv_sec) > 4)
531                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
532                                << 32;
533        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
534 }
535
536 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
537 do {                                                                           \
538         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
539         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
540                 (raw_inode)->xtime ## _extra =                                 \
541                                 ext4_encode_extra_time(&(inode)->xtime);       \
542 } while (0)
543
544 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
545 do {                                                                           \
546         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
547                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
548         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
549                 (raw_inode)->xtime ## _extra =                                 \
550                                 ext4_encode_extra_time(&(einode)->xtime);      \
551 } while (0)
552
553 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
554 do {                                                                           \
555         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
556         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
557                 ext4_decode_extra_time(&(inode)->xtime,                        \
558                                        raw_inode->xtime ## _extra);            \
559 } while (0)
560
561 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
562 do {                                                                           \
563         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
564                 (einode)->xtime.tv_sec =                                       \
565                         (signed)le32_to_cpu((raw_inode)->xtime);               \
566         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
567                 ext4_decode_extra_time(&(einode)->xtime,                       \
568                                        raw_inode->xtime ## _extra);            \
569 } while (0)
570
571 #define i_disk_version osd1.linux1.l_i_version
572
573 #if defined(__KERNEL__) || defined(__linux__)
574 #define i_reserved1     osd1.linux1.l_i_reserved1
575 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
576 #define i_blocks_high   osd2.linux2.l_i_blocks_high
577 #define i_uid_low       i_uid
578 #define i_gid_low       i_gid
579 #define i_uid_high      osd2.linux2.l_i_uid_high
580 #define i_gid_high      osd2.linux2.l_i_gid_high
581 #define i_reserved2     osd2.linux2.l_i_reserved2
582
583 #elif defined(__GNU__)
584
585 #define i_translator    osd1.hurd1.h_i_translator
586 #define i_uid_high      osd2.hurd2.h_i_uid_high
587 #define i_gid_high      osd2.hurd2.h_i_gid_high
588 #define i_author        osd2.hurd2.h_i_author
589
590 #elif defined(__masix__)
591
592 #define i_reserved1     osd1.masix1.m_i_reserved1
593 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
594 #define i_reserved2     osd2.masix2.m_i_reserved2
595
596 #endif /* defined(__KERNEL__) || defined(__linux__) */
597
598 /*
599  * storage for cached extent
600  */
601 struct ext4_ext_cache {
602         ext4_fsblk_t    ec_start;
603         ext4_lblk_t     ec_block;
604         __u32           ec_len; /* must be 32bit to return holes */
605         __u32           ec_type;
606 };
607
608 /*
609  * fourth extended file system inode data in memory
610  */
611 struct ext4_inode_info {
612         __le32  i_data[15];     /* unconverted */
613         __u32   i_flags;
614         ext4_fsblk_t    i_file_acl;
615         __u32   i_dtime;
616
617         /*
618          * i_block_group is the number of the block group which contains
619          * this file's inode.  Constant across the lifetime of the inode,
620          * it is ued for making block allocation decisions - we try to
621          * place a file's data blocks near its inode block, and new inodes
622          * near to their parent directory's inode.
623          */
624         ext4_group_t    i_block_group;
625         unsigned long   i_state_flags;          /* Dynamic state flags */
626
627         ext4_lblk_t             i_dir_start_lookup;
628 #ifdef CONFIG_EXT4_FS_XATTR
629         /*
630          * Extended attributes can be read independently of the main file
631          * data. Taking i_mutex even when reading would cause contention
632          * between readers of EAs and writers of regular file data, so
633          * instead we synchronize on xattr_sem when reading or changing
634          * EAs.
635          */
636         struct rw_semaphore xattr_sem;
637 #endif
638
639         struct list_head i_orphan;      /* unlinked but open inodes */
640
641         /*
642          * i_disksize keeps track of what the inode size is ON DISK, not
643          * in memory.  During truncate, i_size is set to the new size by
644          * the VFS prior to calling ext4_truncate(), but the filesystem won't
645          * set i_disksize to 0 until the truncate is actually under way.
646          *
647          * The intent is that i_disksize always represents the blocks which
648          * are used by this file.  This allows recovery to restart truncate
649          * on orphans if we crash during truncate.  We actually write i_disksize
650          * into the on-disk inode when writing inodes out, instead of i_size.
651          *
652          * The only time when i_disksize and i_size may be different is when
653          * a truncate is in progress.  The only things which change i_disksize
654          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
655          */
656         loff_t  i_disksize;
657
658         /*
659          * i_data_sem is for serialising ext4_truncate() against
660          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
661          * data tree are chopped off during truncate. We can't do that in
662          * ext4 because whenever we perform intermediate commits during
663          * truncate, the inode and all the metadata blocks *must* be in a
664          * consistent state which allows truncation of the orphans to restart
665          * during recovery.  Hence we must fix the get_block-vs-truncate race
666          * by other means, so we have i_data_sem.
667          */
668         struct rw_semaphore i_data_sem;
669         struct inode vfs_inode;
670         struct jbd2_inode jinode;
671
672         struct ext4_ext_cache i_cached_extent;
673         /*
674          * File creation time. Its function is same as that of
675          * struct timespec i_{a,c,m}time in the generic inode.
676          */
677         struct timespec i_crtime;
678
679         /* mballoc */
680         struct list_head i_prealloc_list;
681         spinlock_t i_prealloc_lock;
682
683         /* ialloc */
684         ext4_group_t    i_last_alloc_group;
685
686         /* allocation reservation info for delalloc */
687         unsigned int i_reserved_data_blocks;
688         unsigned int i_reserved_meta_blocks;
689         unsigned int i_allocated_meta_blocks;
690         unsigned short i_delalloc_reserved_flag;
691         sector_t i_da_metadata_calc_last_lblock;
692         int i_da_metadata_calc_len;
693
694         /* on-disk additional length */
695         __u16 i_extra_isize;
696
697         spinlock_t i_block_reservation_lock;
698 #ifdef CONFIG_QUOTA
699         /* quota space reservation, managed internally by quota code */
700         qsize_t i_reserved_quota;
701 #endif
702
703         /* completed IOs that might need unwritten extents handling */
704         struct list_head i_completed_io_list;
705         spinlock_t i_completed_io_lock;
706         /* current io_end structure for async DIO write*/
707         ext4_io_end_t *cur_aio_dio;
708
709         /*
710          * Transactions that contain inode's metadata needed to complete
711          * fsync and fdatasync, respectively.
712          */
713         tid_t i_sync_tid;
714         tid_t i_datasync_tid;
715 };
716
717 /*
718  * File system states
719  */
720 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
721 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
722 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
723
724 /*
725  * Misc. filesystem flags
726  */
727 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
728 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
729 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
730
731 /*
732  * Mount flags
733  */
734 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
735 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
736 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
737 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
738 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
739 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
740 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
741 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
742 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
743 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
744 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
745 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
746 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
747 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
748 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
749 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
750 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
751 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
752 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
753 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
754 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
755 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
756 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
757 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
758 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
759 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
760 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
761 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
762 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
763 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
764
765 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
766 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
767 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
768                                          EXT4_MOUNT_##opt)
769
770 #define ext4_set_bit                    ext2_set_bit
771 #define ext4_set_bit_atomic             ext2_set_bit_atomic
772 #define ext4_clear_bit                  ext2_clear_bit
773 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
774 #define ext4_test_bit                   ext2_test_bit
775 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
776 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
777 #define ext4_find_next_bit              ext2_find_next_bit
778
779 /*
780  * Maximal mount counts between two filesystem checks
781  */
782 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
783 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
784
785 /*
786  * Behaviour when detecting errors
787  */
788 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
789 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
790 #define EXT4_ERRORS_PANIC               3       /* Panic */
791 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
792
793 /*
794  * Structure of the super block
795  */
796 struct ext4_super_block {
797 /*00*/  __le32  s_inodes_count;         /* Inodes count */
798         __le32  s_blocks_count_lo;      /* Blocks count */
799         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
800         __le32  s_free_blocks_count_lo; /* Free blocks count */
801 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
802         __le32  s_first_data_block;     /* First Data Block */
803         __le32  s_log_block_size;       /* Block size */
804         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
805 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
806         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
807         __le32  s_inodes_per_group;     /* # Inodes per group */
808         __le32  s_mtime;                /* Mount time */
809 /*30*/  __le32  s_wtime;                /* Write time */
810         __le16  s_mnt_count;            /* Mount count */
811         __le16  s_max_mnt_count;        /* Maximal mount count */
812         __le16  s_magic;                /* Magic signature */
813         __le16  s_state;                /* File system state */
814         __le16  s_errors;               /* Behaviour when detecting errors */
815         __le16  s_minor_rev_level;      /* minor revision level */
816 /*40*/  __le32  s_lastcheck;            /* time of last check */
817         __le32  s_checkinterval;        /* max. time between checks */
818         __le32  s_creator_os;           /* OS */
819         __le32  s_rev_level;            /* Revision level */
820 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
821         __le16  s_def_resgid;           /* Default gid for reserved blocks */
822         /*
823          * These fields are for EXT4_DYNAMIC_REV superblocks only.
824          *
825          * Note: the difference between the compatible feature set and
826          * the incompatible feature set is that if there is a bit set
827          * in the incompatible feature set that the kernel doesn't
828          * know about, it should refuse to mount the filesystem.
829          *
830          * e2fsck's requirements are more strict; if it doesn't know
831          * about a feature in either the compatible or incompatible
832          * feature set, it must abort and not try to meddle with
833          * things it doesn't understand...
834          */
835         __le32  s_first_ino;            /* First non-reserved inode */
836         __le16  s_inode_size;           /* size of inode structure */
837         __le16  s_block_group_nr;       /* block group # of this superblock */
838         __le32  s_feature_compat;       /* compatible feature set */
839 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
840         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
841 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
842 /*78*/  char    s_volume_name[16];      /* volume name */
843 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
844 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
845         /*
846          * Performance hints.  Directory preallocation should only
847          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
848          */
849         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
850         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
851         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
852         /*
853          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
854          */
855 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
856 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
857         __le32  s_journal_dev;          /* device number of journal file */
858         __le32  s_last_orphan;          /* start of list of inodes to delete */
859         __le32  s_hash_seed[4];         /* HTREE hash seed */
860         __u8    s_def_hash_version;     /* Default hash version to use */
861         __u8    s_reserved_char_pad;
862         __le16  s_desc_size;            /* size of group descriptor */
863 /*100*/ __le32  s_default_mount_opts;
864         __le32  s_first_meta_bg;        /* First metablock block group */
865         __le32  s_mkfs_time;            /* When the filesystem was created */
866         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
867         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
868 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
869         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
870         __le32  s_free_blocks_count_hi; /* Free blocks count */
871         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
872         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
873         __le32  s_flags;                /* Miscellaneous flags */
874         __le16  s_raid_stride;          /* RAID stride */
875         __le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
876         __le64  s_mmp_block;            /* Block for multi-mount protection */
877         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
878         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
879         __u8    s_reserved_char_pad2;
880         __le16  s_reserved_pad;
881         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
882         __u32   s_reserved[160];        /* Padding to the end of the block */
883 };
884
885 #ifdef __KERNEL__
886
887 /*
888  * run-time mount flags
889  */
890 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
891 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
892
893 /*
894  * fourth extended-fs super-block data in memory
895  */
896 struct ext4_sb_info {
897         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
898         unsigned long s_inodes_per_block;/* Number of inodes per block */
899         unsigned long s_blocks_per_group;/* Number of blocks in a group */
900         unsigned long s_inodes_per_group;/* Number of inodes in a group */
901         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
902         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
903         unsigned long s_desc_per_block; /* Number of group descriptors per block */
904         ext4_group_t s_groups_count;    /* Number of groups in the fs */
905         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
906         unsigned long s_overhead_last;  /* Last calculated overhead */
907         unsigned long s_blocks_last;    /* Last seen block count */
908         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
909         struct buffer_head * s_sbh;     /* Buffer containing the super block */
910         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
911         struct buffer_head **s_group_desc;
912         unsigned int s_mount_opt;
913         unsigned int s_mount_flags;
914         ext4_fsblk_t s_sb_block;
915         uid_t s_resuid;
916         gid_t s_resgid;
917         unsigned short s_mount_state;
918         unsigned short s_pad;
919         int s_addr_per_block_bits;
920         int s_desc_per_block_bits;
921         int s_inode_size;
922         int s_first_ino;
923         unsigned int s_inode_readahead_blks;
924         unsigned int s_inode_goal;
925         spinlock_t s_next_gen_lock;
926         u32 s_next_generation;
927         u32 s_hash_seed[4];
928         int s_def_hash_version;
929         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
930         struct percpu_counter s_freeblocks_counter;
931         struct percpu_counter s_freeinodes_counter;
932         struct percpu_counter s_dirs_counter;
933         struct percpu_counter s_dirtyblocks_counter;
934         struct blockgroup_lock *s_blockgroup_lock;
935         struct proc_dir_entry *s_proc;
936         struct kobject s_kobj;
937         struct completion s_kobj_unregister;
938
939         /* Journaling */
940         struct inode *s_journal_inode;
941         struct journal_s *s_journal;
942         struct list_head s_orphan;
943         struct mutex s_orphan_lock;
944         struct mutex s_resize_lock;
945         unsigned long s_commit_interval;
946         u32 s_max_batch_time;
947         u32 s_min_batch_time;
948         struct block_device *journal_bdev;
949 #ifdef CONFIG_JBD2_DEBUG
950         struct timer_list turn_ro_timer;        /* For turning read-only (crash simulation) */
951         wait_queue_head_t ro_wait_queue;        /* For people waiting for the fs to go read-only */
952 #endif
953 #ifdef CONFIG_QUOTA
954         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
955         int s_jquota_fmt;                       /* Format of quota to use */
956 #endif
957         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
958         struct rb_root system_blks;
959
960 #ifdef EXTENTS_STATS
961         /* ext4 extents stats */
962         unsigned long s_ext_min;
963         unsigned long s_ext_max;
964         unsigned long s_depth_max;
965         spinlock_t s_ext_stats_lock;
966         unsigned long s_ext_blocks;
967         unsigned long s_ext_extents;
968 #endif
969
970         /* for buddy allocator */
971         struct ext4_group_info ***s_group_info;
972         struct inode *s_buddy_cache;
973         long s_blocks_reserved;
974         spinlock_t s_reserve_lock;
975         spinlock_t s_md_lock;
976         tid_t s_last_transaction;
977         unsigned short *s_mb_offsets;
978         unsigned int *s_mb_maxs;
979
980         /* tunables */
981         unsigned long s_stripe;
982         unsigned int s_mb_stream_request;
983         unsigned int s_mb_max_to_scan;
984         unsigned int s_mb_min_to_scan;
985         unsigned int s_mb_stats;
986         unsigned int s_mb_order2_reqs;
987         unsigned int s_mb_group_prealloc;
988         unsigned int s_max_writeback_mb_bump;
989         /* where last allocation was done - for stream allocation */
990         unsigned long s_mb_last_group;
991         unsigned long s_mb_last_start;
992
993         /* stats for buddy allocator */
994         spinlock_t s_mb_pa_lock;
995         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
996         atomic_t s_bal_success; /* we found long enough chunks */
997         atomic_t s_bal_allocated;       /* in blocks */
998         atomic_t s_bal_ex_scanned;      /* total extents scanned */
999         atomic_t s_bal_goals;   /* goal hits */
1000         atomic_t s_bal_breaks;  /* too long searches */
1001         atomic_t s_bal_2orders; /* 2^order hits */
1002         spinlock_t s_bal_lock;
1003         unsigned long s_mb_buddies_generated;
1004         unsigned long long s_mb_generation_time;
1005         atomic_t s_mb_lost_chunks;
1006         atomic_t s_mb_preallocated;
1007         atomic_t s_mb_discarded;
1008         atomic_t s_lock_busy;
1009
1010         /* locality groups */
1011         struct ext4_locality_group *s_locality_groups;
1012
1013         /* for write statistics */
1014         unsigned long s_sectors_written_start;
1015         u64 s_kbytes_written;
1016
1017         unsigned int s_log_groups_per_flex;
1018         struct flex_groups *s_flex_groups;
1019
1020         /* workqueue for dio unwritten */
1021         struct workqueue_struct *dio_unwritten_wq;
1022 };
1023
1024 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1025 {
1026         return sb->s_fs_info;
1027 }
1028 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1029 {
1030         return container_of(inode, struct ext4_inode_info, vfs_inode);
1031 }
1032
1033 static inline struct timespec ext4_current_time(struct inode *inode)
1034 {
1035         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1036                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1037 }
1038
1039 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1040 {
1041         return ino == EXT4_ROOT_INO ||
1042                 ino == EXT4_JOURNAL_INO ||
1043                 ino == EXT4_RESIZE_INO ||
1044                 (ino >= EXT4_FIRST_INO(sb) &&
1045                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1046 }
1047
1048 /*
1049  * Inode dynamic state flags
1050  */
1051 enum {
1052         EXT4_STATE_JDATA,               /* journaled data exists */
1053         EXT4_STATE_NEW,                 /* inode is newly created */
1054         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1055         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1056         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1057         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1058         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1059 };
1060
1061 static inline int ext4_test_inode_state(struct inode *inode, int bit)
1062 {
1063         return test_bit(bit, &EXT4_I(inode)->i_state_flags);
1064 }
1065
1066 static inline void ext4_set_inode_state(struct inode *inode, int bit)
1067 {
1068         set_bit(bit, &EXT4_I(inode)->i_state_flags);
1069 }
1070
1071 static inline void ext4_clear_inode_state(struct inode *inode, int bit)
1072 {
1073         clear_bit(bit, &EXT4_I(inode)->i_state_flags);
1074 }
1075 #else
1076 /* Assume that user mode programs are passing in an ext4fs superblock, not
1077  * a kernel struct super_block.  This will allow us to call the feature-test
1078  * macros from user land. */
1079 #define EXT4_SB(sb)     (sb)
1080 #endif
1081
1082 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1083
1084 /*
1085  * Codes for operating systems
1086  */
1087 #define EXT4_OS_LINUX           0
1088 #define EXT4_OS_HURD            1
1089 #define EXT4_OS_MASIX           2
1090 #define EXT4_OS_FREEBSD         3
1091 #define EXT4_OS_LITES           4
1092
1093 /*
1094  * Revision levels
1095  */
1096 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1097 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1098
1099 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1100 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1101
1102 #define EXT4_GOOD_OLD_INODE_SIZE 128
1103
1104 /*
1105  * Feature set definitions
1106  */
1107
1108 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1109         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1110 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1111         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1112 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1113         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1114 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1115         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1116 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1117         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1118 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1119         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1120 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1121         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1122 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1123         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1124 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1125         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1126
1127 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1128 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1129 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1130 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1131 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1132 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1133
1134 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1135 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1136 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1137 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1138 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1139 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1140 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1141
1142 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1143 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1144 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1145 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1146 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1147 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1148 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1149 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1150 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1151 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1152 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1153
1154 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1155 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1156                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1157                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1158                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1159                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1160                                          EXT4_FEATURE_INCOMPAT_FLEX_BG)
1161 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1162                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1163                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1164                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1165                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1166                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1167                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1168
1169 /*
1170  * Default values for user and/or group using reserved blocks
1171  */
1172 #define EXT4_DEF_RESUID         0
1173 #define EXT4_DEF_RESGID         0
1174
1175 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1176
1177 /*
1178  * Default mount options
1179  */
1180 #define EXT4_DEFM_DEBUG         0x0001
1181 #define EXT4_DEFM_BSDGROUPS     0x0002
1182 #define EXT4_DEFM_XATTR_USER    0x0004
1183 #define EXT4_DEFM_ACL           0x0008
1184 #define EXT4_DEFM_UID16         0x0010
1185 #define EXT4_DEFM_JMODE         0x0060
1186 #define EXT4_DEFM_JMODE_DATA    0x0020
1187 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1188 #define EXT4_DEFM_JMODE_WBACK   0x0060
1189
1190 /*
1191  * Default journal batch times
1192  */
1193 #define EXT4_DEF_MIN_BATCH_TIME 0
1194 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1195
1196 /*
1197  * Minimum number of groups in a flexgroup before we separate out
1198  * directories into the first block group of a flexgroup
1199  */
1200 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1201
1202 /*
1203  * Structure of a directory entry
1204  */
1205 #define EXT4_NAME_LEN 255
1206
1207 struct ext4_dir_entry {
1208         __le32  inode;                  /* Inode number */
1209         __le16  rec_len;                /* Directory entry length */
1210         __le16  name_len;               /* Name length */
1211         char    name[EXT4_NAME_LEN];    /* File name */
1212 };
1213
1214 /*
1215  * The new version of the directory entry.  Since EXT4 structures are
1216  * stored in intel byte order, and the name_len field could never be
1217  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1218  * file_type field.
1219  */
1220 struct ext4_dir_entry_2 {
1221         __le32  inode;                  /* Inode number */
1222         __le16  rec_len;                /* Directory entry length */
1223         __u8    name_len;               /* Name length */
1224         __u8    file_type;
1225         char    name[EXT4_NAME_LEN];    /* File name */
1226 };
1227
1228 /*
1229  * Ext4 directory file types.  Only the low 3 bits are used.  The
1230  * other bits are reserved for now.
1231  */
1232 #define EXT4_FT_UNKNOWN         0
1233 #define EXT4_FT_REG_FILE        1
1234 #define EXT4_FT_DIR             2
1235 #define EXT4_FT_CHRDEV          3
1236 #define EXT4_FT_BLKDEV          4
1237 #define EXT4_FT_FIFO            5
1238 #define EXT4_FT_SOCK            6
1239 #define EXT4_FT_SYMLINK         7
1240
1241 #define EXT4_FT_MAX             8
1242
1243 /*
1244  * EXT4_DIR_PAD defines the directory entries boundaries
1245  *
1246  * NOTE: It must be a multiple of 4
1247  */
1248 #define EXT4_DIR_PAD                    4
1249 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1250 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1251                                          ~EXT4_DIR_ROUND)
1252 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1253
1254 /*
1255  * Hash Tree Directory indexing
1256  * (c) Daniel Phillips, 2001
1257  */
1258
1259 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1260                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1261                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
1262 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1263 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1264
1265 /* Legal values for the dx_root hash_version field: */
1266
1267 #define DX_HASH_LEGACY          0
1268 #define DX_HASH_HALF_MD4        1
1269 #define DX_HASH_TEA             2
1270 #define DX_HASH_LEGACY_UNSIGNED 3
1271 #define DX_HASH_HALF_MD4_UNSIGNED       4
1272 #define DX_HASH_TEA_UNSIGNED            5
1273
1274 #ifdef __KERNEL__
1275
1276 /* hash info structure used by the directory hash */
1277 struct dx_hash_info
1278 {
1279         u32             hash;
1280         u32             minor_hash;
1281         int             hash_version;
1282         u32             *seed;
1283 };
1284
1285 #define EXT4_HTREE_EOF  0x7fffffff
1286
1287 /*
1288  * Control parameters used by ext4_htree_next_block
1289  */
1290 #define HASH_NB_ALWAYS          1
1291
1292
1293 /*
1294  * Describe an inode's exact location on disk and in memory
1295  */
1296 struct ext4_iloc
1297 {
1298         struct buffer_head *bh;
1299         unsigned long offset;
1300         ext4_group_t block_group;
1301 };
1302
1303 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1304 {
1305         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1306 }
1307
1308 /*
1309  * This structure is stuffed into the struct file's private_data field
1310  * for directories.  It is where we put information so that we can do
1311  * readdir operations in hash tree order.
1312  */
1313 struct dir_private_info {
1314         struct rb_root  root;
1315         struct rb_node  *curr_node;
1316         struct fname    *extra_fname;
1317         loff_t          last_pos;
1318         __u32           curr_hash;
1319         __u32           curr_minor_hash;
1320         __u32           next_hash;
1321 };
1322
1323 /* calculate the first block number of the group */
1324 static inline ext4_fsblk_t
1325 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1326 {
1327         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1328                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1329 }
1330
1331 /*
1332  * Special error return code only used by dx_probe() and its callers.
1333  */
1334 #define ERR_BAD_DX_DIR  -75000
1335
1336 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1337                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1338
1339 extern struct proc_dir_entry *ext4_proc_root;
1340
1341 /*
1342  * Function prototypes
1343  */
1344
1345 /*
1346  * Ok, these declarations are also in <linux/kernel.h> but none of the
1347  * ext4 source programs needs to include it so they are duplicated here.
1348  */
1349 # define NORET_TYPE     /**/
1350 # define ATTRIB_NORET   __attribute__((noreturn))
1351 # define NORET_AND      noreturn,
1352
1353 /* bitmap.c */
1354 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1355
1356 /* balloc.c */
1357 extern unsigned int ext4_block_group(struct super_block *sb,
1358                         ext4_fsblk_t blocknr);
1359 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1360                         ext4_fsblk_t blocknr);
1361 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1362 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1363                         ext4_group_t group);
1364 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1365                         ext4_fsblk_t goal, unsigned long *count, int *errp);
1366 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1367 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1368 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1369                                 ext4_fsblk_t block, unsigned long count);
1370 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1371 extern void ext4_check_blocks_bitmap(struct super_block *);
1372 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1373                                                     ext4_group_t block_group,
1374                                                     struct buffer_head ** bh);
1375 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1376 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1377                                       ext4_group_t block_group);
1378 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1379                                        struct buffer_head *bh,
1380                                        ext4_group_t group,
1381                                        struct ext4_group_desc *desc);
1382 #define ext4_free_blocks_after_init(sb, group, desc)                    \
1383                 ext4_init_block_bitmap(sb, NULL, group, desc)
1384
1385 /* dir.c */
1386 extern int ext4_check_dir_entry(const char *, struct inode *,
1387                                 struct ext4_dir_entry_2 *,
1388                                 struct buffer_head *, unsigned int);
1389 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1390                                     __u32 minor_hash,
1391                                     struct ext4_dir_entry_2 *dirent);
1392 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1393
1394 /* fsync.c */
1395 extern int ext4_sync_file(struct file *, struct dentry *, int);
1396
1397 /* hash.c */
1398 extern int ext4fs_dirhash(const char *name, int len, struct
1399                           dx_hash_info *hinfo);
1400
1401 /* ialloc.c */
1402 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1403                                     const struct qstr *qstr, __u32 goal);
1404 extern void ext4_free_inode(handle_t *, struct inode *);
1405 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1406 extern unsigned long ext4_count_free_inodes(struct super_block *);
1407 extern unsigned long ext4_count_dirs(struct super_block *);
1408 extern void ext4_check_inodes_bitmap(struct super_block *);
1409 extern unsigned ext4_init_inode_bitmap(struct super_block *sb,
1410                                        struct buffer_head *bh,
1411                                        ext4_group_t group,
1412                                        struct ext4_group_desc *desc);
1413 extern void mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1414
1415 /* mballoc.c */
1416 extern long ext4_mb_stats;
1417 extern long ext4_mb_max_to_scan;
1418 extern int ext4_mb_init(struct super_block *, int);
1419 extern int ext4_mb_release(struct super_block *);
1420 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1421                                 struct ext4_allocation_request *, int *);
1422 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1423 extern void ext4_discard_preallocations(struct inode *);
1424 extern int __init init_ext4_mballoc(void);
1425 extern void exit_ext4_mballoc(void);
1426 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1427                              struct buffer_head *bh, ext4_fsblk_t block,
1428                              unsigned long count, int flags);
1429 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1430                 ext4_group_t i, struct ext4_group_desc *desc);
1431 extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1432 extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1433                                                 ext4_group_t, int);
1434 /* inode.c */
1435 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1436                                                 ext4_lblk_t, int, int *);
1437 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1438                                                 ext4_lblk_t, int, int *);
1439 int ext4_get_block(struct inode *inode, sector_t iblock,
1440                                 struct buffer_head *bh_result, int create);
1441
1442 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1443 extern int  ext4_write_inode(struct inode *, int);
1444 extern int  ext4_setattr(struct dentry *, struct iattr *);
1445 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1446                                 struct kstat *stat);
1447 extern void ext4_delete_inode(struct inode *);
1448 extern int  ext4_sync_inode(handle_t *, struct inode *);
1449 extern void ext4_dirty_inode(struct inode *);
1450 extern int ext4_change_inode_journal_flag(struct inode *, int);
1451 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1452 extern int ext4_can_truncate(struct inode *inode);
1453 extern void ext4_truncate(struct inode *);
1454 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1455 extern void ext4_set_inode_flags(struct inode *);
1456 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1457 extern int ext4_alloc_da_blocks(struct inode *inode);
1458 extern void ext4_set_aops(struct inode *inode);
1459 extern int ext4_writepage_trans_blocks(struct inode *);
1460 extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1461 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1462 extern int ext4_block_truncate_page(handle_t *handle,
1463                 struct address_space *mapping, loff_t from);
1464 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1465 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1466 extern int flush_completed_IO(struct inode *inode);
1467 extern void ext4_da_update_reserve_space(struct inode *inode,
1468                                         int used, int quota_claim);
1469 /* ioctl.c */
1470 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1471 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1472
1473 /* migrate.c */
1474 extern int ext4_ext_migrate(struct inode *);
1475
1476 /* namei.c */
1477 extern unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize);
1478 extern __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize);
1479 extern int ext4_orphan_add(handle_t *, struct inode *);
1480 extern int ext4_orphan_del(handle_t *, struct inode *);
1481 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1482                                 __u32 start_minor_hash, __u32 *next_hash);
1483
1484 /* resize.c */
1485 extern int ext4_group_add(struct super_block *sb,
1486                                 struct ext4_new_group_data *input);
1487 extern int ext4_group_extend(struct super_block *sb,
1488                                 struct ext4_super_block *es,
1489                                 ext4_fsblk_t n_blocks_count);
1490
1491 /* super.c */
1492 extern void __ext4_error(struct super_block *, const char *, const char *, ...)
1493         __attribute__ ((format (printf, 3, 4)));
1494 #define ext4_error(sb, message...)      __ext4_error(sb, __func__, ## message)
1495 extern void __ext4_std_error(struct super_block *, const char *, int);
1496 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
1497         __attribute__ ((format (printf, 3, 4)));
1498 extern void __ext4_warning(struct super_block *, const char *,
1499                           const char *, ...)
1500         __attribute__ ((format (printf, 3, 4)));
1501 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, ## message)
1502 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1503         __attribute__ ((format (printf, 3, 4)));
1504 extern void ext4_grp_locked_error(struct super_block *, ext4_group_t,
1505                                 const char *, const char *, ...)
1506         __attribute__ ((format (printf, 4, 5)));
1507 extern void ext4_update_dynamic_rev(struct super_block *sb);
1508 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1509                                         __u32 compat);
1510 extern int ext4_update_rocompat_feature(handle_t *handle,
1511                                         struct super_block *sb, __u32 rocompat);
1512 extern int ext4_update_incompat_feature(handle_t *handle,
1513                                         struct super_block *sb, __u32 incompat);
1514 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1515                                       struct ext4_group_desc *bg);
1516 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1517                                       struct ext4_group_desc *bg);
1518 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1519                                      struct ext4_group_desc *bg);
1520 extern __u32 ext4_free_blks_count(struct super_block *sb,
1521                                 struct ext4_group_desc *bg);
1522 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1523                                  struct ext4_group_desc *bg);
1524 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1525                                 struct ext4_group_desc *bg);
1526 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1527                                    struct ext4_group_desc *bg);
1528 extern void ext4_block_bitmap_set(struct super_block *sb,
1529                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1530 extern void ext4_inode_bitmap_set(struct super_block *sb,
1531                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1532 extern void ext4_inode_table_set(struct super_block *sb,
1533                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1534 extern void ext4_free_blks_set(struct super_block *sb,
1535                                struct ext4_group_desc *bg, __u32 count);
1536 extern void ext4_free_inodes_set(struct super_block *sb,
1537                                 struct ext4_group_desc *bg, __u32 count);
1538 extern void ext4_used_dirs_set(struct super_block *sb,
1539                                 struct ext4_group_desc *bg, __u32 count);
1540 extern void ext4_itable_unused_set(struct super_block *sb,
1541                                    struct ext4_group_desc *bg, __u32 count);
1542 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1543                                    struct ext4_group_desc *gdp);
1544 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1545                                        struct ext4_group_desc *gdp);
1546
1547 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1548 {
1549         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1550                 le32_to_cpu(es->s_blocks_count_lo);
1551 }
1552
1553 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1554 {
1555         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1556                 le32_to_cpu(es->s_r_blocks_count_lo);
1557 }
1558
1559 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1560 {
1561         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1562                 le32_to_cpu(es->s_free_blocks_count_lo);
1563 }
1564
1565 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1566                                          ext4_fsblk_t blk)
1567 {
1568         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1569         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1570 }
1571
1572 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1573                                               ext4_fsblk_t blk)
1574 {
1575         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1576         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1577 }
1578
1579 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1580                                            ext4_fsblk_t blk)
1581 {
1582         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1583         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1584 }
1585
1586 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1587 {
1588         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1589                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1590                         le32_to_cpu(raw_inode->i_size_lo);
1591         else
1592                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1593 }
1594
1595 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1596 {
1597         raw_inode->i_size_lo = cpu_to_le32(i_size);
1598         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1599 }
1600
1601 static inline
1602 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1603                                             ext4_group_t group)
1604 {
1605          struct ext4_group_info ***grp_info;
1606          long indexv, indexh;
1607          grp_info = EXT4_SB(sb)->s_group_info;
1608          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1609          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1610          return grp_info[indexv][indexh];
1611 }
1612
1613 /*
1614  * Reading s_groups_count requires using smp_rmb() afterwards.  See
1615  * the locking protocol documented in the comments of ext4_group_add()
1616  * in resize.c
1617  */
1618 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
1619 {
1620         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
1621
1622         smp_rmb();
1623         return ngroups;
1624 }
1625
1626 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1627                                              ext4_group_t block_group)
1628 {
1629         return block_group >> sbi->s_log_groups_per_flex;
1630 }
1631
1632 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1633 {
1634         return 1 << sbi->s_log_groups_per_flex;
1635 }
1636
1637 #define ext4_std_error(sb, errno)                               \
1638 do {                                                            \
1639         if ((errno))                                            \
1640                 __ext4_std_error((sb), __func__, (errno));      \
1641 } while (0)
1642
1643 #ifdef CONFIG_SMP
1644 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1645  * counters. So we need to make sure we have free blocks more
1646  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1647  */
1648 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1649 #else
1650 #define EXT4_FREEBLOCKS_WATERMARK 0
1651 #endif
1652
1653 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1654 {
1655         /*
1656          * XXX: replace with spinlock if seen contended -bzzz
1657          */
1658         down_write(&EXT4_I(inode)->i_data_sem);
1659         if (newsize > EXT4_I(inode)->i_disksize)
1660                 EXT4_I(inode)->i_disksize = newsize;
1661         up_write(&EXT4_I(inode)->i_data_sem);
1662         return ;
1663 }
1664
1665 struct ext4_group_info {
1666         unsigned long   bb_state;
1667         struct rb_root  bb_free_root;
1668         ext4_grpblk_t   bb_first_free;  /* first free block */
1669         ext4_grpblk_t   bb_free;        /* total free blocks */
1670         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
1671         struct          list_head bb_prealloc_list;
1672 #ifdef DOUBLE_CHECK
1673         void            *bb_bitmap;
1674 #endif
1675         struct rw_semaphore alloc_sem;
1676         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
1677                                          * regions, index is order.
1678                                          * bb_counters[3] = 5 means
1679                                          * 5 free 8-block regions. */
1680 };
1681
1682 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
1683
1684 #define EXT4_MB_GRP_NEED_INIT(grp)      \
1685         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1686
1687 #define EXT4_MAX_CONTENTION             8
1688 #define EXT4_CONTENTION_THRESHOLD       2
1689
1690 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
1691                                               ext4_group_t group)
1692 {
1693         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
1694 }
1695
1696 /*
1697  * Returns true if the filesystem is busy enough that attempts to
1698  * access the block group locks has run into contention.
1699  */
1700 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
1701 {
1702         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
1703 }
1704
1705 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1706 {
1707         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
1708         if (spin_trylock(lock))
1709                 /*
1710                  * We're able to grab the lock right away, so drop the
1711                  * lock contention counter.
1712                  */
1713                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
1714         else {
1715                 /*
1716                  * The lock is busy, so bump the contention counter,
1717                  * and then wait on the spin lock.
1718                  */
1719                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
1720                                   EXT4_MAX_CONTENTION);
1721                 spin_lock(lock);
1722         }
1723 }
1724
1725 static inline void ext4_unlock_group(struct super_block *sb,
1726                                         ext4_group_t group)
1727 {
1728         spin_unlock(ext4_group_lock_ptr(sb, group));
1729 }
1730
1731 /*
1732  * Inodes and files operations
1733  */
1734
1735 /* dir.c */
1736 extern const struct file_operations ext4_dir_operations;
1737
1738 /* file.c */
1739 extern const struct inode_operations ext4_file_inode_operations;
1740 extern const struct file_operations ext4_file_operations;
1741
1742 /* namei.c */
1743 extern const struct inode_operations ext4_dir_inode_operations;
1744 extern const struct inode_operations ext4_special_inode_operations;
1745 extern struct dentry *ext4_get_parent(struct dentry *child);
1746
1747 /* symlink.c */
1748 extern const struct inode_operations ext4_symlink_inode_operations;
1749 extern const struct inode_operations ext4_fast_symlink_inode_operations;
1750
1751 /* block_validity */
1752 extern void ext4_release_system_zone(struct super_block *sb);
1753 extern int ext4_setup_system_zone(struct super_block *sb);
1754 extern int __init init_ext4_system_zone(void);
1755 extern void exit_ext4_system_zone(void);
1756 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
1757                                  ext4_fsblk_t start_blk,
1758                                  unsigned int count);
1759
1760 /* extents.c */
1761 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1762 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1763 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1764                                        int chunk);
1765 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1766                                ext4_lblk_t iblock, unsigned int max_blocks,
1767                                struct buffer_head *bh_result, int flags);
1768 extern void ext4_ext_truncate(struct inode *);
1769 extern void ext4_ext_init(struct super_block *);
1770 extern void ext4_ext_release(struct super_block *);
1771 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1772                           loff_t len);
1773 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
1774                           ssize_t len);
1775 extern int ext4_get_blocks(handle_t *handle, struct inode *inode,
1776                            sector_t block, unsigned int max_blocks,
1777                            struct buffer_head *bh, int flags);
1778 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1779                         __u64 start, __u64 len);
1780 /* move_extent.c */
1781 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
1782                              __u64 start_orig, __u64 start_donor,
1783                              __u64 len, __u64 *moved_len);
1784
1785
1786 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
1787 enum ext4_state_bits {
1788         BH_Uninit       /* blocks are allocated but uninitialized on disk */
1789           = BH_JBDPrivateStart,
1790 };
1791
1792 BUFFER_FNS(Uninit, uninit)
1793 TAS_BUFFER_FNS(Uninit, uninit)
1794
1795 /*
1796  * Add new method to test wether block and inode bitmaps are properly
1797  * initialized. With uninit_bg reading the block from disk is not enough
1798  * to mark the bitmap uptodate. We need to also zero-out the bitmap
1799  */
1800 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
1801
1802 static inline int bitmap_uptodate(struct buffer_head *bh)
1803 {
1804         return (buffer_uptodate(bh) &&
1805                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
1806 }
1807 static inline void set_bitmap_uptodate(struct buffer_head *bh)
1808 {
1809         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
1810 }
1811
1812 #endif  /* __KERNEL__ */
1813
1814 #endif  /* _EXT4_H */