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xen: cleancache shim to Xen Transcendent Memory
[linux-2.6/next.git] / fs / ext4 / ext4.h
blob4daaf2b753f4fa037fd783ac34e47e15d1438b55
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
112
113 struct ext4_allocation_request {
114 /* target inode for block we're allocating */
115 struct inode *inode;
116 /* how many blocks we want to allocate */
117 unsigned int len;
118 /* logical block in target inode */
119 ext4_lblk_t logical;
120 /* the closest logical allocated block to the left */
121 ext4_lblk_t lleft;
122 /* the closest logical allocated block to the right */
123 ext4_lblk_t lright;
124 /* phys. target (a hint) */
125 ext4_fsblk_t goal;
126 /* phys. block for the closest logical allocated block to the left */
127 ext4_fsblk_t pleft;
128 /* phys. block for the closest logical allocated block to the right */
129 ext4_fsblk_t pright;
130 /* flags. see above EXT4_MB_HINT_* */
131 unsigned int flags;
132 };
133
134 /*
135 * Logical to physical block mapping, used by ext4_map_blocks()
136 *
137 * This structure is used to pass requests into ext4_map_blocks() as
138 * well as to store the information returned by ext4_map_blocks(). It
139 * takes less room on the stack than a struct buffer_head.
140 */
141 #define EXT4_MAP_NEW (1 << BH_New)
142 #define EXT4_MAP_MAPPED (1 << BH_Mapped)
143 #define EXT4_MAP_UNWRITTEN (1 << BH_Unwritten)
144 #define EXT4_MAP_BOUNDARY (1 << BH_Boundary)
145 #define EXT4_MAP_UNINIT (1 << BH_Uninit)
146 #define EXT4_MAP_FLAGS (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
147 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
148 EXT4_MAP_UNINIT)
149
150 struct ext4_map_blocks {
151 ext4_fsblk_t m_pblk;
152 ext4_lblk_t m_lblk;
153 unsigned int m_len;
154 unsigned int m_flags;
155 };
156
157 /*
158 * For delayed allocation tracking
159 */
160 struct mpage_da_data {
161 struct inode *inode;
162 sector_t b_blocknr; /* start block number of extent */
163 size_t b_size; /* size of extent */
164 unsigned long b_state; /* state of the extent */
165 unsigned long first_page, next_page; /* extent of pages */
166 struct writeback_control *wbc;
167 int io_done;
168 int pages_written;
169 int retval;
170 };
171
172 /*
173 * Flags for ext4_io_end->flags
174 */
175 #define EXT4_IO_END_UNWRITTEN 0x0001
176 #define EXT4_IO_END_ERROR 0x0002
177
178 struct ext4_io_page {
179 struct page *p_page;
180 atomic_t p_count;
181 };
182
183 #define MAX_IO_PAGES 128
184
185 typedef struct ext4_io_end {
186 struct list_head list; /* per-file finished IO list */
187 struct inode *inode; /* file being written to */
188 unsigned int flag; /* unwritten or not */
189 struct page *page; /* page struct for buffer write */
190 loff_t offset; /* offset in the file */
191 ssize_t size; /* size of the extent */
192 struct work_struct work; /* data work queue */
193 struct kiocb *iocb; /* iocb struct for AIO */
194 int result; /* error value for AIO */
195 int num_io_pages;
196 struct ext4_io_page *pages[MAX_IO_PAGES];
197 } ext4_io_end_t;
198
199 struct ext4_io_submit {
200 int io_op;
201 struct bio *io_bio;
202 ext4_io_end_t *io_end;
203 struct ext4_io_page *io_page;
204 sector_t io_next_block;
205 };
206
207 /*
208 * Special inodes numbers
209 */
210 #define EXT4_BAD_INO 1 /* Bad blocks inode */
211 #define EXT4_ROOT_INO 2 /* Root inode */
212 #define EXT4_BOOT_LOADER_INO 5 /* Boot loader inode */
213 #define EXT4_UNDEL_DIR_INO 6 /* Undelete directory inode */
214 #define EXT4_RESIZE_INO 7 /* Reserved group descriptors inode */
215 #define EXT4_JOURNAL_INO 8 /* Journal inode */
216
217 /* First non-reserved inode for old ext4 filesystems */
218 #define EXT4_GOOD_OLD_FIRST_INO 11
219
220 /*
221 * Maximal count of links to a file
222 */
223 #define EXT4_LINK_MAX 65000
224
225 /*
226 * Macro-instructions used to manage several block sizes
227 */
228 #define EXT4_MIN_BLOCK_SIZE 1024
229 #define EXT4_MAX_BLOCK_SIZE 65536
230 #define EXT4_MIN_BLOCK_LOG_SIZE 10
231 #define EXT4_MAX_BLOCK_LOG_SIZE 16
232 #ifdef __KERNEL__
233 # define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize)
234 #else
235 # define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
236 #endif
237 #define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
238 #ifdef __KERNEL__
239 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
240 #else
241 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
242 #endif
243 #ifdef __KERNEL__
244 #define EXT4_ADDR_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_addr_per_block_bits)
245 #define EXT4_INODE_SIZE(s) (EXT4_SB(s)->s_inode_size)
246 #define EXT4_FIRST_INO(s) (EXT4_SB(s)->s_first_ino)
247 #else
248 #define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
249 EXT4_GOOD_OLD_INODE_SIZE : \
250 (s)->s_inode_size)
251 #define EXT4_FIRST_INO(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
252 EXT4_GOOD_OLD_FIRST_INO : \
253 (s)->s_first_ino)
254 #endif
255 #define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
256
257 /*
258 * Structure of a blocks group descriptor
259 */
260 struct ext4_group_desc
261 {
262 __le32 bg_block_bitmap_lo; /* Blocks bitmap block */
263 __le32 bg_inode_bitmap_lo; /* Inodes bitmap block */
264 __le32 bg_inode_table_lo; /* Inodes table block */
265 __le16 bg_free_blocks_count_lo;/* Free blocks count */
266 __le16 bg_free_inodes_count_lo;/* Free inodes count */
267 __le16 bg_used_dirs_count_lo; /* Directories count */
268 __le16 bg_flags; /* EXT4_BG_flags (INODE_UNINIT, etc) */
269 __u32 bg_reserved[2]; /* Likely block/inode bitmap checksum */
270 __le16 bg_itable_unused_lo; /* Unused inodes count */
271 __le16 bg_checksum; /* crc16(sb_uuid+group+desc) */
272 __le32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
273 __le32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
274 __le32 bg_inode_table_hi; /* Inodes table block MSB */
275 __le16 bg_free_blocks_count_hi;/* Free blocks count MSB */
276 __le16 bg_free_inodes_count_hi;/* Free inodes count MSB */
277 __le16 bg_used_dirs_count_hi; /* Directories count MSB */
278 __le16 bg_itable_unused_hi; /* Unused inodes count MSB */
279 __u32 bg_reserved2[3];
280 };
281
282 /*
283 * Structure of a flex block group info
284 */
285
286 struct flex_groups {
287 atomic_t free_inodes;
288 atomic_t free_blocks;
289 atomic_t used_dirs;
290 };
291
292 #define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */
293 #define EXT4_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */
294 #define EXT4_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
295
296 /*
297 * Macro-instructions used to manage group descriptors
298 */
299 #define EXT4_MIN_DESC_SIZE 32
300 #define EXT4_MIN_DESC_SIZE_64BIT 64
301 #define EXT4_MAX_DESC_SIZE EXT4_MIN_BLOCK_SIZE
302 #define EXT4_DESC_SIZE(s) (EXT4_SB(s)->s_desc_size)
303 #ifdef __KERNEL__
304 # define EXT4_BLOCKS_PER_GROUP(s) (EXT4_SB(s)->s_blocks_per_group)
305 # define EXT4_DESC_PER_BLOCK(s) (EXT4_SB(s)->s_desc_per_block)
306 # define EXT4_INODES_PER_GROUP(s) (EXT4_SB(s)->s_inodes_per_group)
307 # define EXT4_DESC_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_desc_per_block_bits)
308 #else
309 # define EXT4_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
310 # define EXT4_DESC_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
311 # define EXT4_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
312 #endif
313
314 /*
315 * Constants relative to the data blocks
316 */
317 #define EXT4_NDIR_BLOCKS 12
318 #define EXT4_IND_BLOCK EXT4_NDIR_BLOCKS
319 #define EXT4_DIND_BLOCK (EXT4_IND_BLOCK + 1)
320 #define EXT4_TIND_BLOCK (EXT4_DIND_BLOCK + 1)
321 #define EXT4_N_BLOCKS (EXT4_TIND_BLOCK + 1)
322
323 /*
324 * Inode flags
325 */
326 #define EXT4_SECRM_FL 0x00000001 /* Secure deletion */
327 #define EXT4_UNRM_FL 0x00000002 /* Undelete */
328 #define EXT4_COMPR_FL 0x00000004 /* Compress file */
329 #define EXT4_SYNC_FL 0x00000008 /* Synchronous updates */
330 #define EXT4_IMMUTABLE_FL 0x00000010 /* Immutable file */
331 #define EXT4_APPEND_FL 0x00000020 /* writes to file may only append */
332 #define EXT4_NODUMP_FL 0x00000040 /* do not dump file */
333 #define EXT4_NOATIME_FL 0x00000080 /* do not update atime */
334 /* Reserved for compression usage... */
335 #define EXT4_DIRTY_FL 0x00000100
336 #define EXT4_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
337 #define EXT4_NOCOMPR_FL 0x00000400 /* Don't compress */
338 #define EXT4_ECOMPR_FL 0x00000800 /* Compression error */
339 /* End compression flags --- maybe not all used */
340 #define EXT4_INDEX_FL 0x00001000 /* hash-indexed directory */
341 #define EXT4_IMAGIC_FL 0x00002000 /* AFS directory */
342 #define EXT4_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
343 #define EXT4_NOTAIL_FL 0x00008000 /* file tail should not be merged */
344 #define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
345 #define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
346 #define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
347 #define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
348 #define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */
349 #define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */
350 #define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
351
352 #define EXT4_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */
353 #define EXT4_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */
354
355 /* Flags that should be inherited by new inodes from their parent. */
356 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
357 EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
358 EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
359 EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
360 EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
361
362 /* Flags that are appropriate for regular files (all but dir-specific ones). */
363 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
364
365 /* Flags that are appropriate for non-directories/regular files. */
366 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
367
368 /* Mask out flags that are inappropriate for the given type of inode. */
369 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
370 {
371 if (S_ISDIR(mode))
372 return flags;
373 else if (S_ISREG(mode))
374 return flags & EXT4_REG_FLMASK;
375 else
376 return flags & EXT4_OTHER_FLMASK;
377 }
378
379 /*
380 * Inode flags used for atomic set/get
381 */
382 enum {
383 EXT4_INODE_SECRM = 0, /* Secure deletion */
384 EXT4_INODE_UNRM = 1, /* Undelete */
385 EXT4_INODE_COMPR = 2, /* Compress file */
386 EXT4_INODE_SYNC = 3, /* Synchronous updates */
387 EXT4_INODE_IMMUTABLE = 4, /* Immutable file */
388 EXT4_INODE_APPEND = 5, /* writes to file may only append */
389 EXT4_INODE_NODUMP = 6, /* do not dump file */
390 EXT4_INODE_NOATIME = 7, /* do not update atime */
391 /* Reserved for compression usage... */
392 EXT4_INODE_DIRTY = 8,
393 EXT4_INODE_COMPRBLK = 9, /* One or more compressed clusters */
394 EXT4_INODE_NOCOMPR = 10, /* Don't compress */
395 EXT4_INODE_ECOMPR = 11, /* Compression error */
396 /* End compression flags --- maybe not all used */
397 EXT4_INODE_INDEX = 12, /* hash-indexed directory */
398 EXT4_INODE_IMAGIC = 13, /* AFS directory */
399 EXT4_INODE_JOURNAL_DATA = 14, /* file data should be journaled */
400 EXT4_INODE_NOTAIL = 15, /* file tail should not be merged */
401 EXT4_INODE_DIRSYNC = 16, /* dirsync behaviour (directories only) */
402 EXT4_INODE_TOPDIR = 17, /* Top of directory hierarchies*/
403 EXT4_INODE_HUGE_FILE = 18, /* Set to each huge file */
404 EXT4_INODE_EXTENTS = 19, /* Inode uses extents */
405 EXT4_INODE_EA_INODE = 21, /* Inode used for large EA */
406 EXT4_INODE_EOFBLOCKS = 22, /* Blocks allocated beyond EOF */
407 EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */
408 };
409
410 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
411 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
412 printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
413 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
414
415 /*
416 * Since it's pretty easy to mix up bit numbers and hex values, and we
417 * can't do a compile-time test for ENUM values, we use a run-time
418 * test to make sure that EXT4_XXX_FL is consistent with respect to
419 * EXT4_INODE_XXX. If all is well the printk and BUG_ON will all drop
420 * out so it won't cost any extra space in the compiled kernel image.
421 * But it's important that these values are the same, since we are
422 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
423 * must be consistent with the values of FS_XXX_FL defined in
424 * include/linux/fs.h and the on-disk values found in ext2, ext3, and
425 * ext4 filesystems, and of course the values defined in e2fsprogs.
426 *
427 * It's not paranoia if the Murphy's Law really *is* out to get you. :-)
428 */
429 static inline void ext4_check_flag_values(void)
430 {
431 CHECK_FLAG_VALUE(SECRM);
432 CHECK_FLAG_VALUE(UNRM);
433 CHECK_FLAG_VALUE(COMPR);
434 CHECK_FLAG_VALUE(SYNC);
435 CHECK_FLAG_VALUE(IMMUTABLE);
436 CHECK_FLAG_VALUE(APPEND);
437 CHECK_FLAG_VALUE(NODUMP);
438 CHECK_FLAG_VALUE(NOATIME);
439 CHECK_FLAG_VALUE(DIRTY);
440 CHECK_FLAG_VALUE(COMPRBLK);
441 CHECK_FLAG_VALUE(NOCOMPR);
442 CHECK_FLAG_VALUE(ECOMPR);
443 CHECK_FLAG_VALUE(INDEX);
444 CHECK_FLAG_VALUE(IMAGIC);
445 CHECK_FLAG_VALUE(JOURNAL_DATA);
446 CHECK_FLAG_VALUE(NOTAIL);
447 CHECK_FLAG_VALUE(DIRSYNC);
448 CHECK_FLAG_VALUE(TOPDIR);
449 CHECK_FLAG_VALUE(HUGE_FILE);
450 CHECK_FLAG_VALUE(EXTENTS);
451 CHECK_FLAG_VALUE(EA_INODE);
452 CHECK_FLAG_VALUE(EOFBLOCKS);
453 CHECK_FLAG_VALUE(RESERVED);
454 }
455
456 /* Used to pass group descriptor data when online resize is done */
457 struct ext4_new_group_input {
458 __u32 group; /* Group number for this data */
459 __u64 block_bitmap; /* Absolute block number of block bitmap */
460 __u64 inode_bitmap; /* Absolute block number of inode bitmap */
461 __u64 inode_table; /* Absolute block number of inode table start */
462 __u32 blocks_count; /* Total number of blocks in this group */
463 __u16 reserved_blocks; /* Number of reserved blocks in this group */
464 __u16 unused;
465 };
466
467 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
468 struct compat_ext4_new_group_input {
469 u32 group;
470 compat_u64 block_bitmap;
471 compat_u64 inode_bitmap;
472 compat_u64 inode_table;
473 u32 blocks_count;
474 u16 reserved_blocks;
475 u16 unused;
476 };
477 #endif
478
479 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
480 struct ext4_new_group_data {
481 __u32 group;
482 __u64 block_bitmap;
483 __u64 inode_bitmap;
484 __u64 inode_table;
485 __u32 blocks_count;
486 __u16 reserved_blocks;
487 __u16 unused;
488 __u32 free_blocks_count;
489 };
490
491 /*
492 * Flags used by ext4_map_blocks()
493 */
494 /* Allocate any needed blocks and/or convert an unitialized
495 extent to be an initialized ext4 */
496 #define EXT4_GET_BLOCKS_CREATE 0x0001
497 /* Request the creation of an unitialized extent */
498 #define EXT4_GET_BLOCKS_UNINIT_EXT 0x0002
499 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT (EXT4_GET_BLOCKS_UNINIT_EXT|\
500 EXT4_GET_BLOCKS_CREATE)
501 /* Caller is from the delayed allocation writeout path,
502 so set the magic i_delalloc_reserve_flag after taking the
503 inode allocation semaphore for */
504 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE 0x0004
505 /* caller is from the direct IO path, request to creation of an
506 unitialized extents if not allocated, split the uninitialized
507 extent if blocks has been preallocated already*/
508 #define EXT4_GET_BLOCKS_PRE_IO 0x0008
509 #define EXT4_GET_BLOCKS_CONVERT 0x0010
510 #define EXT4_GET_BLOCKS_IO_CREATE_EXT (EXT4_GET_BLOCKS_PRE_IO|\
511 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
512 /* Convert extent to initialized after IO complete */
513 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT (EXT4_GET_BLOCKS_CONVERT|\
514 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
515
516 /*
517 * Flags used by ext4_free_blocks
518 */
519 #define EXT4_FREE_BLOCKS_METADATA 0x0001
520 #define EXT4_FREE_BLOCKS_FORGET 0x0002
521 #define EXT4_FREE_BLOCKS_VALIDATED 0x0004
522
523 /*
524 * ioctl commands
525 */
526 #define EXT4_IOC_GETFLAGS FS_IOC_GETFLAGS
527 #define EXT4_IOC_SETFLAGS FS_IOC_SETFLAGS
528 #define EXT4_IOC_GETVERSION _IOR('f', 3, long)
529 #define EXT4_IOC_SETVERSION _IOW('f', 4, long)
530 #define EXT4_IOC_GETVERSION_OLD FS_IOC_GETVERSION
531 #define EXT4_IOC_SETVERSION_OLD FS_IOC_SETVERSION
532 #ifdef CONFIG_JBD2_DEBUG
533 #define EXT4_IOC_WAIT_FOR_READONLY _IOR('f', 99, long)
534 #endif
535 #define EXT4_IOC_GETRSVSZ _IOR('f', 5, long)
536 #define EXT4_IOC_SETRSVSZ _IOW('f', 6, long)
537 #define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
538 #define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
539 #define EXT4_IOC_MIGRATE _IO('f', 9)
540 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
541 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
542 #define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12)
543 #define EXT4_IOC_MOVE_EXT _IOWR('f', 15, struct move_extent)
544
545 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
546 /*
547 * ioctl commands in 32 bit emulation
548 */
549 #define EXT4_IOC32_GETFLAGS FS_IOC32_GETFLAGS
550 #define EXT4_IOC32_SETFLAGS FS_IOC32_SETFLAGS
551 #define EXT4_IOC32_GETVERSION _IOR('f', 3, int)
552 #define EXT4_IOC32_SETVERSION _IOW('f', 4, int)
553 #define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int)
554 #define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int)
555 #define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int)
556 #define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input)
557 #ifdef CONFIG_JBD2_DEBUG
558 #define EXT4_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int)
559 #endif
560 #define EXT4_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION
561 #define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
562 #endif
563
564 /* Max physical block we can address w/o extents */
565 #define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF
566
567 /*
568 * Structure of an inode on the disk
569 */
570 struct ext4_inode {
571 __le16 i_mode; /* File mode */
572 __le16 i_uid; /* Low 16 bits of Owner Uid */
573 __le32 i_size_lo; /* Size in bytes */
574 __le32 i_atime; /* Access time */
575 __le32 i_ctime; /* Inode Change time */
576 __le32 i_mtime; /* Modification time */
577 __le32 i_dtime; /* Deletion Time */
578 __le16 i_gid; /* Low 16 bits of Group Id */
579 __le16 i_links_count; /* Links count */
580 __le32 i_blocks_lo; /* Blocks count */
581 __le32 i_flags; /* File flags */
582 union {
583 struct {
584 __le32 l_i_version;
585 } linux1;
586 struct {
587 __u32 h_i_translator;
588 } hurd1;
589 struct {
590 __u32 m_i_reserved1;
591 } masix1;
592 } osd1; /* OS dependent 1 */
593 __le32 i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
594 __le32 i_generation; /* File version (for NFS) */
595 __le32 i_file_acl_lo; /* File ACL */
596 __le32 i_size_high;
597 __le32 i_obso_faddr; /* Obsoleted fragment address */
598 union {
599 struct {
600 __le16 l_i_blocks_high; /* were l_i_reserved1 */
601 __le16 l_i_file_acl_high;
602 __le16 l_i_uid_high; /* these 2 fields */
603 __le16 l_i_gid_high; /* were reserved2[0] */
604 __u32 l_i_reserved2;
605 } linux2;
606 struct {
607 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
608 __u16 h_i_mode_high;
609 __u16 h_i_uid_high;
610 __u16 h_i_gid_high;
611 __u32 h_i_author;
612 } hurd2;
613 struct {
614 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
615 __le16 m_i_file_acl_high;
616 __u32 m_i_reserved2[2];
617 } masix2;
618 } osd2; /* OS dependent 2 */
619 __le16 i_extra_isize;
620 __le16 i_pad1;
621 __le32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
622 __le32 i_mtime_extra; /* extra Modification time(nsec << 2 | epoch) */
623 __le32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
624 __le32 i_crtime; /* File Creation time */
625 __le32 i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
626 __le32 i_version_hi; /* high 32 bits for 64-bit version */
627 };
628
629 struct move_extent {
630 __u32 reserved; /* should be zero */
631 __u32 donor_fd; /* donor file descriptor */
632 __u64 orig_start; /* logical start offset in block for orig */
633 __u64 donor_start; /* logical start offset in block for donor */
634 __u64 len; /* block length to be moved */
635 __u64 moved_len; /* moved block length */
636 };
637
638 #define EXT4_EPOCH_BITS 2
639 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
640 #define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS)
641
642 /*
643 * Extended fields will fit into an inode if the filesystem was formatted
644 * with large inodes (-I 256 or larger) and there are not currently any EAs
645 * consuming all of the available space. For new inodes we always reserve
646 * enough space for the kernel's known extended fields, but for inodes
647 * created with an old kernel this might not have been the case. None of
648 * the extended inode fields is critical for correct filesystem operation.
649 * This macro checks if a certain field fits in the inode. Note that
650 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
651 */
652 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field) \
653 ((offsetof(typeof(*ext4_inode), field) + \
654 sizeof((ext4_inode)->field)) \
655 <= (EXT4_GOOD_OLD_INODE_SIZE + \
656 (einode)->i_extra_isize)) \
657
658 static inline __le32 ext4_encode_extra_time(struct timespec *time)
659 {
660 return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
661 (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
662 ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
663 }
664
665 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
666 {
667 if (sizeof(time->tv_sec) > 4)
668 time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
669 << 32;
670 time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
671 }
672
673 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode) \
674 do { \
675 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \
676 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
677 (raw_inode)->xtime ## _extra = \
678 ext4_encode_extra_time(&(inode)->xtime); \
679 } while (0)
680
681 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \
682 do { \
683 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
684 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec); \
685 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
686 (raw_inode)->xtime ## _extra = \
687 ext4_encode_extra_time(&(einode)->xtime); \
688 } while (0)
689
690 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode) \
691 do { \
692 (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime); \
693 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
694 ext4_decode_extra_time(&(inode)->xtime, \
695 raw_inode->xtime ## _extra); \
696 else \
697 (inode)->xtime.tv_nsec = 0; \
698 } while (0)
699
700 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode) \
701 do { \
702 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
703 (einode)->xtime.tv_sec = \
704 (signed)le32_to_cpu((raw_inode)->xtime); \
705 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
706 ext4_decode_extra_time(&(einode)->xtime, \
707 raw_inode->xtime ## _extra); \
708 else \
709 (einode)->xtime.tv_nsec = 0; \
710 } while (0)
711
712 #define i_disk_version osd1.linux1.l_i_version
713
714 #if defined(__KERNEL__) || defined(__linux__)
715 #define i_reserved1 osd1.linux1.l_i_reserved1
716 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
717 #define i_blocks_high osd2.linux2.l_i_blocks_high
718 #define i_uid_low i_uid
719 #define i_gid_low i_gid
720 #define i_uid_high osd2.linux2.l_i_uid_high
721 #define i_gid_high osd2.linux2.l_i_gid_high
722 #define i_reserved2 osd2.linux2.l_i_reserved2
723
724 #elif defined(__GNU__)
725
726 #define i_translator osd1.hurd1.h_i_translator
727 #define i_uid_high osd2.hurd2.h_i_uid_high
728 #define i_gid_high osd2.hurd2.h_i_gid_high
729 #define i_author osd2.hurd2.h_i_author
730
731 #elif defined(__masix__)
732
733 #define i_reserved1 osd1.masix1.m_i_reserved1
734 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
735 #define i_reserved2 osd2.masix2.m_i_reserved2
736
737 #endif /* defined(__KERNEL__) || defined(__linux__) */
738
739 /*
740 * storage for cached extent
741 * If ec_len == 0, then the cache is invalid.
742 * If ec_start == 0, then the cache represents a gap (null mapping)
743 */
744 struct ext4_ext_cache {
745 ext4_fsblk_t ec_start;
746 ext4_lblk_t ec_block;
747 __u32 ec_len; /* must be 32bit to return holes */
748 };
749
750 /*
751 * fourth extended file system inode data in memory
752 */
753 struct ext4_inode_info {
754 __le32 i_data[15]; /* unconverted */
755 __u32 i_dtime;
756 ext4_fsblk_t i_file_acl;
757
758 /*
759 * i_block_group is the number of the block group which contains
760 * this file's inode. Constant across the lifetime of the inode,
761 * it is ued for making block allocation decisions - we try to
762 * place a file's data blocks near its inode block, and new inodes
763 * near to their parent directory's inode.
764 */
765 ext4_group_t i_block_group;
766 ext4_lblk_t i_dir_start_lookup;
767 #if (BITS_PER_LONG < 64)
768 unsigned long i_state_flags; /* Dynamic state flags */
769 #endif
770 unsigned long i_flags;
771
772 #ifdef CONFIG_EXT4_FS_XATTR
773 /*
774 * Extended attributes can be read independently of the main file
775 * data. Taking i_mutex even when reading would cause contention
776 * between readers of EAs and writers of regular file data, so
777 * instead we synchronize on xattr_sem when reading or changing
778 * EAs.
779 */
780 struct rw_semaphore xattr_sem;
781 #endif
782
783 struct list_head i_orphan; /* unlinked but open inodes */
784
785 /*
786 * i_disksize keeps track of what the inode size is ON DISK, not
787 * in memory. During truncate, i_size is set to the new size by
788 * the VFS prior to calling ext4_truncate(), but the filesystem won't
789 * set i_disksize to 0 until the truncate is actually under way.
790 *
791 * The intent is that i_disksize always represents the blocks which
792 * are used by this file. This allows recovery to restart truncate
793 * on orphans if we crash during truncate. We actually write i_disksize
794 * into the on-disk inode when writing inodes out, instead of i_size.
795 *
796 * The only time when i_disksize and i_size may be different is when
797 * a truncate is in progress. The only things which change i_disksize
798 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
799 */
800 loff_t i_disksize;
801
802 /*
803 * i_data_sem is for serialising ext4_truncate() against
804 * ext4_getblock(). In the 2.4 ext2 design, great chunks of inode's
805 * data tree are chopped off during truncate. We can't do that in
806 * ext4 because whenever we perform intermediate commits during
807 * truncate, the inode and all the metadata blocks *must* be in a
808 * consistent state which allows truncation of the orphans to restart
809 * during recovery. Hence we must fix the get_block-vs-truncate race
810 * by other means, so we have i_data_sem.
811 */
812 struct rw_semaphore i_data_sem;
813 struct inode vfs_inode;
814 struct jbd2_inode *jinode;
815
816 struct ext4_ext_cache i_cached_extent;
817 /*
818 * File creation time. Its function is same as that of
819 * struct timespec i_{a,c,m}time in the generic inode.
820 */
821 struct timespec i_crtime;
822
823 /* mballoc */
824 struct list_head i_prealloc_list;
825 spinlock_t i_prealloc_lock;
826
827 /* ialloc */
828 ext4_group_t i_last_alloc_group;
829
830 /* allocation reservation info for delalloc */
831 unsigned int i_reserved_data_blocks;
832 unsigned int i_reserved_meta_blocks;
833 unsigned int i_allocated_meta_blocks;
834 ext4_lblk_t i_da_metadata_calc_last_lblock;
835 int i_da_metadata_calc_len;
836
837 /* on-disk additional length */
838 __u16 i_extra_isize;
839
840 #ifdef CONFIG_QUOTA
841 /* quota space reservation, managed internally by quota code */
842 qsize_t i_reserved_quota;
843 #endif
844
845 /* completed IOs that might need unwritten extents handling */
846 struct list_head i_completed_io_list;
847 spinlock_t i_completed_io_lock;
848 atomic_t i_ioend_count; /* Number of outstanding io_end structs */
849 /* current io_end structure for async DIO write*/
850 ext4_io_end_t *cur_aio_dio;
851 atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
852
853 spinlock_t i_block_reservation_lock;
854
855 /*
856 * Transactions that contain inode's metadata needed to complete
857 * fsync and fdatasync, respectively.
858 */
859 tid_t i_sync_tid;
860 tid_t i_datasync_tid;
861 };
862
863 /*
864 * File system states
865 */
866 #define EXT4_VALID_FS 0x0001 /* Unmounted cleanly */
867 #define EXT4_ERROR_FS 0x0002 /* Errors detected */
868 #define EXT4_ORPHAN_FS 0x0004 /* Orphans being recovered */
869
870 /*
871 * Misc. filesystem flags
872 */
873 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
874 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
875 #define EXT2_FLAGS_TEST_FILESYS 0x0004 /* to test development code */
876
877 /*
878 * Mount flags
879 */
880 #define EXT4_MOUNT_OLDALLOC 0x00002 /* Don't use the new Orlov allocator */
881 #define EXT4_MOUNT_GRPID 0x00004 /* Create files with directory's group */
882 #define EXT4_MOUNT_DEBUG 0x00008 /* Some debugging messages */
883 #define EXT4_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */
884 #define EXT4_MOUNT_ERRORS_RO 0x00020 /* Remount fs ro on errors */
885 #define EXT4_MOUNT_ERRORS_PANIC 0x00040 /* Panic on errors */
886 #define EXT4_MOUNT_MINIX_DF 0x00080 /* Mimics the Minix statfs */
887 #define EXT4_MOUNT_NOLOAD 0x00100 /* Don't use existing journal*/
888 #define EXT4_MOUNT_DATA_FLAGS 0x00C00 /* Mode for data writes: */
889 #define EXT4_MOUNT_JOURNAL_DATA 0x00400 /* Write data to journal */
890 #define EXT4_MOUNT_ORDERED_DATA 0x00800 /* Flush data before commit */
891 #define EXT4_MOUNT_WRITEBACK_DATA 0x00C00 /* No data ordering */
892 #define EXT4_MOUNT_UPDATE_JOURNAL 0x01000 /* Update the journal format */
893 #define EXT4_MOUNT_NO_UID32 0x02000 /* Disable 32-bit UIDs */
894 #define EXT4_MOUNT_XATTR_USER 0x04000 /* Extended user attributes */
895 #define EXT4_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */
896 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */
897 #define EXT4_MOUNT_BARRIER 0x20000 /* Use block barriers */
898 #define EXT4_MOUNT_QUOTA 0x80000 /* Some quota option set */
899 #define EXT4_MOUNT_USRQUOTA 0x100000 /* "old" user quota */
900 #define EXT4_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */
901 #define EXT4_MOUNT_DIOREAD_NOLOCK 0x400000 /* Enable support for dio read nolocking */
902 #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */
903 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
904 #define EXT4_MOUNT_I_VERSION 0x2000000 /* i_version support */
905 #define EXT4_MOUNT_MBLK_IO_SUBMIT 0x4000000 /* multi-block io submits */
906 #define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */
907 #define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */
908 #define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */
909 #define EXT4_MOUNT_DISCARD 0x40000000 /* Issue DISCARD requests */
910 #define EXT4_MOUNT_INIT_INODE_TABLE 0x80000000 /* Initialize uninitialized itables */
911
912 #define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \
913 ~EXT4_MOUNT_##opt
914 #define set_opt(sb, opt) EXT4_SB(sb)->s_mount_opt |= \
915 EXT4_MOUNT_##opt
916 #define test_opt(sb, opt) (EXT4_SB(sb)->s_mount_opt & \
917 EXT4_MOUNT_##opt)
918
919 #define clear_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 &= \
920 ~EXT4_MOUNT2_##opt
921 #define set_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 |= \
922 EXT4_MOUNT2_##opt
923 #define test_opt2(sb, opt) (EXT4_SB(sb)->s_mount_opt2 & \
924 EXT4_MOUNT2_##opt)
925
926 #define ext4_set_bit __test_and_set_bit_le
927 #define ext4_set_bit_atomic ext2_set_bit_atomic
928 #define ext4_clear_bit __test_and_clear_bit_le
929 #define ext4_clear_bit_atomic ext2_clear_bit_atomic
930 #define ext4_test_bit test_bit_le
931 #define ext4_find_first_zero_bit find_first_zero_bit_le
932 #define ext4_find_next_zero_bit find_next_zero_bit_le
933 #define ext4_find_next_bit find_next_bit_le
934
935 /*
936 * Maximal mount counts between two filesystem checks
937 */
938 #define EXT4_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
939 #define EXT4_DFL_CHECKINTERVAL 0 /* Don't use interval check */
940
941 /*
942 * Behaviour when detecting errors
943 */
944 #define EXT4_ERRORS_CONTINUE 1 /* Continue execution */
945 #define EXT4_ERRORS_RO 2 /* Remount fs read-only */
946 #define EXT4_ERRORS_PANIC 3 /* Panic */
947 #define EXT4_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE
948
949 /*
950 * Structure of the super block
951 */
952 struct ext4_super_block {
953 /*00*/ __le32 s_inodes_count; /* Inodes count */
954 __le32 s_blocks_count_lo; /* Blocks count */
955 __le32 s_r_blocks_count_lo; /* Reserved blocks count */
956 __le32 s_free_blocks_count_lo; /* Free blocks count */
957 /*10*/ __le32 s_free_inodes_count; /* Free inodes count */
958 __le32 s_first_data_block; /* First Data Block */
959 __le32 s_log_block_size; /* Block size */
960 __le32 s_obso_log_frag_size; /* Obsoleted fragment size */
961 /*20*/ __le32 s_blocks_per_group; /* # Blocks per group */
962 __le32 s_obso_frags_per_group; /* Obsoleted fragments per group */
963 __le32 s_inodes_per_group; /* # Inodes per group */
964 __le32 s_mtime; /* Mount time */
965 /*30*/ __le32 s_wtime; /* Write time */
966 __le16 s_mnt_count; /* Mount count */
967 __le16 s_max_mnt_count; /* Maximal mount count */
968 __le16 s_magic; /* Magic signature */
969 __le16 s_state; /* File system state */
970 __le16 s_errors; /* Behaviour when detecting errors */
971 __le16 s_minor_rev_level; /* minor revision level */
972 /*40*/ __le32 s_lastcheck; /* time of last check */
973 __le32 s_checkinterval; /* max. time between checks */
974 __le32 s_creator_os; /* OS */
975 __le32 s_rev_level; /* Revision level */
976 /*50*/ __le16 s_def_resuid; /* Default uid for reserved blocks */
977 __le16 s_def_resgid; /* Default gid for reserved blocks */
978 /*
979 * These fields are for EXT4_DYNAMIC_REV superblocks only.
980 *
981 * Note: the difference between the compatible feature set and
982 * the incompatible feature set is that if there is a bit set
983 * in the incompatible feature set that the kernel doesn't
984 * know about, it should refuse to mount the filesystem.
985 *
986 * e2fsck's requirements are more strict; if it doesn't know
987 * about a feature in either the compatible or incompatible
988 * feature set, it must abort and not try to meddle with
989 * things it doesn't understand...
990 */
991 __le32 s_first_ino; /* First non-reserved inode */
992 __le16 s_inode_size; /* size of inode structure */
993 __le16 s_block_group_nr; /* block group # of this superblock */
994 __le32 s_feature_compat; /* compatible feature set */
995 /*60*/ __le32 s_feature_incompat; /* incompatible feature set */
996 __le32 s_feature_ro_compat; /* readonly-compatible feature set */
997 /*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */
998 /*78*/ char s_volume_name[16]; /* volume name */
999 /*88*/ char s_last_mounted[64]; /* directory where last mounted */
1000 /*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */
1001 /*
1002 * Performance hints. Directory preallocation should only
1003 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1004 */
1005 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
1006 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
1007 __le16 s_reserved_gdt_blocks; /* Per group desc for online growth */
1008 /*
1009 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1010 */
1011 /*D0*/ __u8 s_journal_uuid[16]; /* uuid of journal superblock */
1012 /*E0*/ __le32 s_journal_inum; /* inode number of journal file */
1013 __le32 s_journal_dev; /* device number of journal file */
1014 __le32 s_last_orphan; /* start of list of inodes to delete */
1015 __le32 s_hash_seed[4]; /* HTREE hash seed */
1016 __u8 s_def_hash_version; /* Default hash version to use */
1017 __u8 s_jnl_backup_type;
1018 __le16 s_desc_size; /* size of group descriptor */
1019 /*100*/ __le32 s_default_mount_opts;
1020 __le32 s_first_meta_bg; /* First metablock block group */
1021 __le32 s_mkfs_time; /* When the filesystem was created */
1022 __le32 s_jnl_blocks[17]; /* Backup of the journal inode */
1023 /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1024 /*150*/ __le32 s_blocks_count_hi; /* Blocks count */
1025 __le32 s_r_blocks_count_hi; /* Reserved blocks count */
1026 __le32 s_free_blocks_count_hi; /* Free blocks count */
1027 __le16 s_min_extra_isize; /* All inodes have at least # bytes */
1028 __le16 s_want_extra_isize; /* New inodes should reserve # bytes */
1029 __le32 s_flags; /* Miscellaneous flags */
1030 __le16 s_raid_stride; /* RAID stride */
1031 __le16 s_mmp_interval; /* # seconds to wait in MMP checking */
1032 __le64 s_mmp_block; /* Block for multi-mount protection */
1033 __le32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
1034 __u8 s_log_groups_per_flex; /* FLEX_BG group size */
1035 __u8 s_reserved_char_pad;
1036 __le16 s_reserved_pad;
1037 __le64 s_kbytes_written; /* nr of lifetime kilobytes written */
1038 __le32 s_snapshot_inum; /* Inode number of active snapshot */
1039 __le32 s_snapshot_id; /* sequential ID of active snapshot */
1040 __le64 s_snapshot_r_blocks_count; /* reserved blocks for active
1041 snapshot's future use */
1042 __le32 s_snapshot_list; /* inode number of the head of the
1043 on-disk snapshot list */
1044 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1045 __le32 s_error_count; /* number of fs errors */
1046 __le32 s_first_error_time; /* first time an error happened */
1047 __le32 s_first_error_ino; /* inode involved in first error */
1048 __le64 s_first_error_block; /* block involved of first error */
1049 __u8 s_first_error_func[32]; /* function where the error happened */
1050 __le32 s_first_error_line; /* line number where error happened */
1051 __le32 s_last_error_time; /* most recent time of an error */
1052 __le32 s_last_error_ino; /* inode involved in last error */
1053 __le32 s_last_error_line; /* line number where error happened */
1054 __le64 s_last_error_block; /* block involved of last error */
1055 __u8 s_last_error_func[32]; /* function where the error happened */
1056 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1057 __u8 s_mount_opts[64];
1058 __le32 s_reserved[112]; /* Padding to the end of the block */
1059 };
1060
1061 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1062
1063 #ifdef __KERNEL__
1064
1065 /*
1066 * run-time mount flags
1067 */
1068 #define EXT4_MF_MNTDIR_SAMPLED 0x0001
1069 #define EXT4_MF_FS_ABORTED 0x0002 /* Fatal error detected */
1070
1071 /*
1072 * fourth extended-fs super-block data in memory
1073 */
1074 struct ext4_sb_info {
1075 unsigned long s_desc_size; /* Size of a group descriptor in bytes */
1076 unsigned long s_inodes_per_block;/* Number of inodes per block */
1077 unsigned long s_blocks_per_group;/* Number of blocks in a group */
1078 unsigned long s_inodes_per_group;/* Number of inodes in a group */
1079 unsigned long s_itb_per_group; /* Number of inode table blocks per group */
1080 unsigned long s_gdb_count; /* Number of group descriptor blocks */
1081 unsigned long s_desc_per_block; /* Number of group descriptors per block */
1082 ext4_group_t s_groups_count; /* Number of groups in the fs */
1083 ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1084 unsigned long s_overhead_last; /* Last calculated overhead */
1085 unsigned long s_blocks_last; /* Last seen block count */
1086 loff_t s_bitmap_maxbytes; /* max bytes for bitmap files */
1087 struct buffer_head * s_sbh; /* Buffer containing the super block */
1088 struct ext4_super_block *s_es; /* Pointer to the super block in the buffer */
1089 struct buffer_head **s_group_desc;
1090 unsigned int s_mount_opt;
1091 unsigned int s_mount_opt2;
1092 unsigned int s_mount_flags;
1093 ext4_fsblk_t s_sb_block;
1094 uid_t s_resuid;
1095 gid_t s_resgid;
1096 unsigned short s_mount_state;
1097 unsigned short s_pad;
1098 int s_addr_per_block_bits;
1099 int s_desc_per_block_bits;
1100 int s_inode_size;
1101 int s_first_ino;
1102 unsigned int s_inode_readahead_blks;
1103 unsigned int s_inode_goal;
1104 spinlock_t s_next_gen_lock;
1105 u32 s_next_generation;
1106 u32 s_hash_seed[4];
1107 int s_def_hash_version;
1108 int s_hash_unsigned; /* 3 if hash should be signed, 0 if not */
1109 struct percpu_counter s_freeblocks_counter;
1110 struct percpu_counter s_freeinodes_counter;
1111 struct percpu_counter s_dirs_counter;
1112 struct percpu_counter s_dirtyblocks_counter;
1113 struct blockgroup_lock *s_blockgroup_lock;
1114 struct proc_dir_entry *s_proc;
1115 struct kobject s_kobj;
1116 struct completion s_kobj_unregister;
1117
1118 /* Journaling */
1119 struct journal_s *s_journal;
1120 struct list_head s_orphan;
1121 struct mutex s_orphan_lock;
1122 struct mutex s_resize_lock;
1123 unsigned long s_commit_interval;
1124 u32 s_max_batch_time;
1125 u32 s_min_batch_time;
1126 struct block_device *journal_bdev;
1127 #ifdef CONFIG_JBD2_DEBUG
1128 struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */
1129 wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */
1130 #endif
1131 #ifdef CONFIG_QUOTA
1132 char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
1133 int s_jquota_fmt; /* Format of quota to use */
1134 #endif
1135 unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1136 struct rb_root system_blks;
1137
1138 #ifdef EXTENTS_STATS
1139 /* ext4 extents stats */
1140 unsigned long s_ext_min;
1141 unsigned long s_ext_max;
1142 unsigned long s_depth_max;
1143 spinlock_t s_ext_stats_lock;
1144 unsigned long s_ext_blocks;
1145 unsigned long s_ext_extents;
1146 #endif
1147
1148 /* for buddy allocator */
1149 struct ext4_group_info ***s_group_info;
1150 struct inode *s_buddy_cache;
1151 spinlock_t s_md_lock;
1152 unsigned short *s_mb_offsets;
1153 unsigned int *s_mb_maxs;
1154
1155 /* tunables */
1156 unsigned long s_stripe;
1157 unsigned int s_mb_stream_request;
1158 unsigned int s_mb_max_to_scan;
1159 unsigned int s_mb_min_to_scan;
1160 unsigned int s_mb_stats;
1161 unsigned int s_mb_order2_reqs;
1162 unsigned int s_mb_group_prealloc;
1163 unsigned int s_max_writeback_mb_bump;
1164 /* where last allocation was done - for stream allocation */
1165 unsigned long s_mb_last_group;
1166 unsigned long s_mb_last_start;
1167
1168 /* stats for buddy allocator */
1169 atomic_t s_bal_reqs; /* number of reqs with len > 1 */
1170 atomic_t s_bal_success; /* we found long enough chunks */
1171 atomic_t s_bal_allocated; /* in blocks */
1172 atomic_t s_bal_ex_scanned; /* total extents scanned */
1173 atomic_t s_bal_goals; /* goal hits */
1174 atomic_t s_bal_breaks; /* too long searches */
1175 atomic_t s_bal_2orders; /* 2^order hits */
1176 spinlock_t s_bal_lock;
1177 unsigned long s_mb_buddies_generated;
1178 unsigned long long s_mb_generation_time;
1179 atomic_t s_mb_lost_chunks;
1180 atomic_t s_mb_preallocated;
1181 atomic_t s_mb_discarded;
1182 atomic_t s_lock_busy;
1183
1184 /* locality groups */
1185 struct ext4_locality_group __percpu *s_locality_groups;
1186
1187 /* for write statistics */
1188 unsigned long s_sectors_written_start;
1189 u64 s_kbytes_written;
1190
1191 unsigned int s_log_groups_per_flex;
1192 struct flex_groups *s_flex_groups;
1193
1194 /* workqueue for dio unwritten */
1195 struct workqueue_struct *dio_unwritten_wq;
1196
1197 /* timer for periodic error stats printing */
1198 struct timer_list s_err_report;
1199
1200 /* Lazy inode table initialization info */
1201 struct ext4_li_request *s_li_request;
1202 /* Wait multiplier for lazy initialization thread */
1203 unsigned int s_li_wait_mult;
1204 };
1205
1206 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1207 {
1208 return sb->s_fs_info;
1209 }
1210 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1211 {
1212 return container_of(inode, struct ext4_inode_info, vfs_inode);
1213 }
1214
1215 static inline struct timespec ext4_current_time(struct inode *inode)
1216 {
1217 return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1218 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1219 }
1220
1221 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1222 {
1223 return ino == EXT4_ROOT_INO ||
1224 ino == EXT4_JOURNAL_INO ||
1225 ino == EXT4_RESIZE_INO ||
1226 (ino >= EXT4_FIRST_INO(sb) &&
1227 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1228 }
1229
1230 /*
1231 * Inode dynamic state flags
1232 */
1233 enum {
1234 EXT4_STATE_JDATA, /* journaled data exists */
1235 EXT4_STATE_NEW, /* inode is newly created */
1236 EXT4_STATE_XATTR, /* has in-inode xattrs */
1237 EXT4_STATE_NO_EXPAND, /* No space for expansion */
1238 EXT4_STATE_DA_ALLOC_CLOSE, /* Alloc DA blks on close */
1239 EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */
1240 EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/
1241 EXT4_STATE_NEWENTRY, /* File just added to dir */
1242 EXT4_STATE_DELALLOC_RESERVED, /* blks already reserved for delalloc */
1243 };
1244
1245 #define EXT4_INODE_BIT_FNS(name, field, offset) \
1246 static inline int ext4_test_inode_##name(struct inode *inode, int bit) \
1247 { \
1248 return test_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1249 } \
1250 static inline void ext4_set_inode_##name(struct inode *inode, int bit) \
1251 { \
1252 set_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1253 } \
1254 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1255 { \
1256 clear_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1257 }
1258
1259 EXT4_INODE_BIT_FNS(flag, flags, 0)
1260 #if (BITS_PER_LONG < 64)
1261 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1262
1263 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1264 {
1265 (ei)->i_state_flags = 0;
1266 }
1267 #else
1268 EXT4_INODE_BIT_FNS(state, flags, 32)
1269
1270 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1271 {
1272 /* We depend on the fact that callers will set i_flags */
1273 }
1274 #endif
1275 #else
1276 /* Assume that user mode programs are passing in an ext4fs superblock, not
1277 * a kernel struct super_block. This will allow us to call the feature-test
1278 * macros from user land. */
1279 #define EXT4_SB(sb) (sb)
1280 #endif
1281
1282 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1283
1284 /*
1285 * Codes for operating systems
1286 */
1287 #define EXT4_OS_LINUX 0
1288 #define EXT4_OS_HURD 1
1289 #define EXT4_OS_MASIX 2
1290 #define EXT4_OS_FREEBSD 3
1291 #define EXT4_OS_LITES 4
1292
1293 /*
1294 * Revision levels
1295 */
1296 #define EXT4_GOOD_OLD_REV 0 /* The good old (original) format */
1297 #define EXT4_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
1298
1299 #define EXT4_CURRENT_REV EXT4_GOOD_OLD_REV
1300 #define EXT4_MAX_SUPP_REV EXT4_DYNAMIC_REV
1301
1302 #define EXT4_GOOD_OLD_INODE_SIZE 128
1303
1304 /*
1305 * Feature set definitions
1306 */
1307
1308 #define EXT4_HAS_COMPAT_FEATURE(sb,mask) \
1309 ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1310 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask) \
1311 ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1312 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask) \
1313 ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1314 #define EXT4_SET_COMPAT_FEATURE(sb,mask) \
1315 EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1316 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask) \
1317 EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1318 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask) \
1319 EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1320 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask) \
1321 EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1322 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
1323 EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1324 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask) \
1325 EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1326
1327 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001
1328 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002
1329 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004
1330 #define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008
1331 #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010
1332 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020
1333
1334 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
1335 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
1336 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
1337 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
1338 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
1339 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
1340 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
1341
1342 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
1343 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
1344 #define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
1345 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
1346 #define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
1347 #define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
1348 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
1349 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
1350 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
1351 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */
1352 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */
1353
1354 #define EXT4_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
1355 #define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1356 EXT4_FEATURE_INCOMPAT_RECOVER| \
1357 EXT4_FEATURE_INCOMPAT_META_BG| \
1358 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1359 EXT4_FEATURE_INCOMPAT_64BIT| \
1360 EXT4_FEATURE_INCOMPAT_FLEX_BG)
1361 #define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1362 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1363 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1364 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1365 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1366 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1367 EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1368
1369 /*
1370 * Default values for user and/or group using reserved blocks
1371 */
1372 #define EXT4_DEF_RESUID 0
1373 #define EXT4_DEF_RESGID 0
1374
1375 #define EXT4_DEF_INODE_READAHEAD_BLKS 32
1376
1377 /*
1378 * Default mount options
1379 */
1380 #define EXT4_DEFM_DEBUG 0x0001
1381 #define EXT4_DEFM_BSDGROUPS 0x0002
1382 #define EXT4_DEFM_XATTR_USER 0x0004
1383 #define EXT4_DEFM_ACL 0x0008
1384 #define EXT4_DEFM_UID16 0x0010
1385 #define EXT4_DEFM_JMODE 0x0060
1386 #define EXT4_DEFM_JMODE_DATA 0x0020
1387 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1388 #define EXT4_DEFM_JMODE_WBACK 0x0060
1389 #define EXT4_DEFM_NOBARRIER 0x0100
1390 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1391 #define EXT4_DEFM_DISCARD 0x0400
1392 #define EXT4_DEFM_NODELALLOC 0x0800
1393
1394 /*
1395 * Default journal batch times
1396 */
1397 #define EXT4_DEF_MIN_BATCH_TIME 0
1398 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1399
1400 /*
1401 * Minimum number of groups in a flexgroup before we separate out
1402 * directories into the first block group of a flexgroup
1403 */
1404 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1405
1406 /*
1407 * Structure of a directory entry
1408 */
1409 #define EXT4_NAME_LEN 255
1410
1411 struct ext4_dir_entry {
1412 __le32 inode; /* Inode number */
1413 __le16 rec_len; /* Directory entry length */
1414 __le16 name_len; /* Name length */
1415 char name[EXT4_NAME_LEN]; /* File name */
1416 };
1417
1418 /*
1419 * The new version of the directory entry. Since EXT4 structures are
1420 * stored in intel byte order, and the name_len field could never be
1421 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1422 * file_type field.
1423 */
1424 struct ext4_dir_entry_2 {
1425 __le32 inode; /* Inode number */
1426 __le16 rec_len; /* Directory entry length */
1427 __u8 name_len; /* Name length */
1428 __u8 file_type;
1429 char name[EXT4_NAME_LEN]; /* File name */
1430 };
1431
1432 /*
1433 * Ext4 directory file types. Only the low 3 bits are used. The
1434 * other bits are reserved for now.
1435 */
1436 #define EXT4_FT_UNKNOWN 0
1437 #define EXT4_FT_REG_FILE 1
1438 #define EXT4_FT_DIR 2
1439 #define EXT4_FT_CHRDEV 3
1440 #define EXT4_FT_BLKDEV 4
1441 #define EXT4_FT_FIFO 5
1442 #define EXT4_FT_SOCK 6
1443 #define EXT4_FT_SYMLINK 7
1444
1445 #define EXT4_FT_MAX 8
1446
1447 /*
1448 * EXT4_DIR_PAD defines the directory entries boundaries
1449 *
1450 * NOTE: It must be a multiple of 4
1451 */
1452 #define EXT4_DIR_PAD 4
1453 #define EXT4_DIR_ROUND (EXT4_DIR_PAD - 1)
1454 #define EXT4_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT4_DIR_ROUND) & \
1455 ~EXT4_DIR_ROUND)
1456 #define EXT4_MAX_REC_LEN ((1<<16)-1)
1457
1458 /*
1459 * If we ever get support for fs block sizes > page_size, we'll need
1460 * to remove the #if statements in the next two functions...
1461 */
1462 static inline unsigned int
1463 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1464 {
1465 unsigned len = le16_to_cpu(dlen);
1466
1467 #if (PAGE_CACHE_SIZE >= 65536)
1468 if (len == EXT4_MAX_REC_LEN || len == 0)
1469 return blocksize;
1470 return (len & 65532) | ((len & 3) << 16);
1471 #else
1472 return len;
1473 #endif
1474 }
1475
1476 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1477 {
1478 if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1479 BUG();
1480 #if (PAGE_CACHE_SIZE >= 65536)
1481 if (len < 65536)
1482 return cpu_to_le16(len);
1483 if (len == blocksize) {
1484 if (blocksize == 65536)
1485 return cpu_to_le16(EXT4_MAX_REC_LEN);
1486 else
1487 return cpu_to_le16(0);
1488 }
1489 return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1490 #else
1491 return cpu_to_le16(len);
1492 #endif
1493 }
1494
1495 /*
1496 * Hash Tree Directory indexing
1497 * (c) Daniel Phillips, 2001
1498 */
1499
1500 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1501 EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1502 ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1503 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1504 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1505
1506 /* Legal values for the dx_root hash_version field: */
1507
1508 #define DX_HASH_LEGACY 0
1509 #define DX_HASH_HALF_MD4 1
1510 #define DX_HASH_TEA 2
1511 #define DX_HASH_LEGACY_UNSIGNED 3
1512 #define DX_HASH_HALF_MD4_UNSIGNED 4
1513 #define DX_HASH_TEA_UNSIGNED 5
1514
1515 #ifdef __KERNEL__
1516
1517 /* hash info structure used by the directory hash */
1518 struct dx_hash_info
1519 {
1520 u32 hash;
1521 u32 minor_hash;
1522 int hash_version;
1523 u32 *seed;
1524 };
1525
1526 #define EXT4_HTREE_EOF 0x7fffffff
1527
1528 /*
1529 * Control parameters used by ext4_htree_next_block
1530 */
1531 #define HASH_NB_ALWAYS 1
1532
1533
1534 /*
1535 * Describe an inode's exact location on disk and in memory
1536 */
1537 struct ext4_iloc
1538 {
1539 struct buffer_head *bh;
1540 unsigned long offset;
1541 ext4_group_t block_group;
1542 };
1543
1544 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1545 {
1546 return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1547 }
1548
1549 /*
1550 * This structure is stuffed into the struct file's private_data field
1551 * for directories. It is where we put information so that we can do
1552 * readdir operations in hash tree order.
1553 */
1554 struct dir_private_info {
1555 struct rb_root root;
1556 struct rb_node *curr_node;
1557 struct fname *extra_fname;
1558 loff_t last_pos;
1559 __u32 curr_hash;
1560 __u32 curr_minor_hash;
1561 __u32 next_hash;
1562 };
1563
1564 /* calculate the first block number of the group */
1565 static inline ext4_fsblk_t
1566 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1567 {
1568 return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1569 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1570 }
1571
1572 /*
1573 * Special error return code only used by dx_probe() and its callers.
1574 */
1575 #define ERR_BAD_DX_DIR -75000
1576
1577 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1578 ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1579
1580 /*
1581 * Timeout and state flag for lazy initialization inode thread.
1582 */
1583 #define EXT4_DEF_LI_WAIT_MULT 10
1584 #define EXT4_DEF_LI_MAX_START_DELAY 5
1585 #define EXT4_LAZYINIT_QUIT 0x0001
1586 #define EXT4_LAZYINIT_RUNNING 0x0002
1587
1588 /*
1589 * Lazy inode table initialization info
1590 */
1591 struct ext4_lazy_init {
1592 unsigned long li_state;
1593
1594 wait_queue_head_t li_wait_daemon;
1595 wait_queue_head_t li_wait_task;
1596 struct timer_list li_timer;
1597 struct task_struct *li_task;
1598
1599 struct list_head li_request_list;
1600 struct mutex li_list_mtx;
1601 };
1602
1603 struct ext4_li_request {
1604 struct super_block *lr_super;
1605 struct ext4_sb_info *lr_sbi;
1606 ext4_group_t lr_next_group;
1607 struct list_head lr_request;
1608 unsigned long lr_next_sched;
1609 unsigned long lr_timeout;
1610 };
1611
1612 struct ext4_features {
1613 struct kobject f_kobj;
1614 struct completion f_kobj_unregister;
1615 };
1616
1617 /*
1618 * Function prototypes
1619 */
1620
1621 /*
1622 * Ok, these declarations are also in <linux/kernel.h> but none of the
1623 * ext4 source programs needs to include it so they are duplicated here.
1624 */
1625 # define NORET_TYPE /**/
1626 # define ATTRIB_NORET __attribute__((noreturn))
1627 # define NORET_AND noreturn,
1628
1629 /* bitmap.c */
1630 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1631
1632 /* balloc.c */
1633 extern unsigned int ext4_block_group(struct super_block *sb,
1634 ext4_fsblk_t blocknr);
1635 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1636 ext4_fsblk_t blocknr);
1637 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1638 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1639 ext4_group_t group);
1640 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1641 ext4_fsblk_t goal, unsigned long *count, int *errp);
1642 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1643 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1644 ext4_fsblk_t block, unsigned long count);
1645 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1646 extern void ext4_check_blocks_bitmap(struct super_block *);
1647 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1648 ext4_group_t block_group,
1649 struct buffer_head ** bh);
1650 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1651 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1652 ext4_group_t block_group);
1653 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1654 struct buffer_head *bh,
1655 ext4_group_t group,
1656 struct ext4_group_desc *desc);
1657 #define ext4_free_blocks_after_init(sb, group, desc) \
1658 ext4_init_block_bitmap(sb, NULL, group, desc)
1659
1660 /* dir.c */
1661 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1662 struct file *,
1663 struct ext4_dir_entry_2 *,
1664 struct buffer_head *, unsigned int);
1665 #define ext4_check_dir_entry(dir, filp, de, bh, offset) \
1666 unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1667 (de), (bh), (offset)))
1668 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1669 __u32 minor_hash,
1670 struct ext4_dir_entry_2 *dirent);
1671 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1672
1673 /* fsync.c */
1674 extern int ext4_sync_file(struct file *, int);
1675 extern int ext4_flush_completed_IO(struct inode *);
1676
1677 /* hash.c */
1678 extern int ext4fs_dirhash(const char *name, int len, struct
1679 dx_hash_info *hinfo);
1680
1681 /* ialloc.c */
1682 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1683 const struct qstr *qstr, __u32 goal);
1684 extern void ext4_free_inode(handle_t *, struct inode *);
1685 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1686 extern unsigned long ext4_count_free_inodes(struct super_block *);
1687 extern unsigned long ext4_count_dirs(struct super_block *);
1688 extern void ext4_check_inodes_bitmap(struct super_block *);
1689 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1690 extern int ext4_init_inode_table(struct super_block *sb,
1691 ext4_group_t group, int barrier);
1692
1693 /* mballoc.c */
1694 extern long ext4_mb_stats;
1695 extern long ext4_mb_max_to_scan;
1696 extern int ext4_mb_init(struct super_block *, int);
1697 extern int ext4_mb_release(struct super_block *);
1698 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1699 struct ext4_allocation_request *, int *);
1700 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1701 extern void ext4_discard_preallocations(struct inode *);
1702 extern int __init ext4_init_mballoc(void);
1703 extern void ext4_exit_mballoc(void);
1704 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1705 struct buffer_head *bh, ext4_fsblk_t block,
1706 unsigned long count, int flags);
1707 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1708 ext4_group_t i, struct ext4_group_desc *desc);
1709 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1710
1711 /* inode.c */
1712 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1713 ext4_lblk_t, int, int *);
1714 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1715 ext4_lblk_t, int, int *);
1716 int ext4_get_block(struct inode *inode, sector_t iblock,
1717 struct buffer_head *bh_result, int create);
1718
1719 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1720 extern int ext4_write_inode(struct inode *, struct writeback_control *);
1721 extern int ext4_setattr(struct dentry *, struct iattr *);
1722 extern int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1723 struct kstat *stat);
1724 extern void ext4_evict_inode(struct inode *);
1725 extern void ext4_clear_inode(struct inode *);
1726 extern int ext4_sync_inode(handle_t *, struct inode *);
1727 extern void ext4_dirty_inode(struct inode *);
1728 extern int ext4_change_inode_journal_flag(struct inode *, int);
1729 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1730 extern int ext4_can_truncate(struct inode *inode);
1731 extern void ext4_truncate(struct inode *);
1732 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1733 extern void ext4_set_inode_flags(struct inode *);
1734 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1735 extern int ext4_alloc_da_blocks(struct inode *inode);
1736 extern void ext4_set_aops(struct inode *inode);
1737 extern int ext4_writepage_trans_blocks(struct inode *);
1738 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1739 extern int ext4_block_truncate_page(handle_t *handle,
1740 struct address_space *mapping, loff_t from);
1741 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1742 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1743 extern void ext4_da_update_reserve_space(struct inode *inode,
1744 int used, int quota_claim);
1745 /* ioctl.c */
1746 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1747 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1748
1749 /* migrate.c */
1750 extern int ext4_ext_migrate(struct inode *);
1751
1752 /* namei.c */
1753 extern int ext4_orphan_add(handle_t *, struct inode *);
1754 extern int ext4_orphan_del(handle_t *, struct inode *);
1755 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1756 __u32 start_minor_hash, __u32 *next_hash);
1757
1758 /* resize.c */
1759 extern int ext4_group_add(struct super_block *sb,
1760 struct ext4_new_group_data *input);
1761 extern int ext4_group_extend(struct super_block *sb,
1762 struct ext4_super_block *es,
1763 ext4_fsblk_t n_blocks_count);
1764
1765 /* super.c */
1766 extern void __ext4_error(struct super_block *, const char *, unsigned int,
1767 const char *, ...)
1768 __attribute__ ((format (printf, 4, 5)));
1769 #define ext4_error(sb, message...) __ext4_error(sb, __func__, \
1770 __LINE__, ## message)
1771 extern void ext4_error_inode(struct inode *, const char *, unsigned int,
1772 ext4_fsblk_t, const char *, ...)
1773 __attribute__ ((format (printf, 5, 6)));
1774 extern void ext4_error_file(struct file *, const char *, unsigned int,
1775 ext4_fsblk_t, const char *, ...)
1776 __attribute__ ((format (printf, 5, 6)));
1777 extern void __ext4_std_error(struct super_block *, const char *,
1778 unsigned int, int);
1779 extern void __ext4_abort(struct super_block *, const char *, unsigned int,
1780 const char *, ...)
1781 __attribute__ ((format (printf, 4, 5)));
1782 #define ext4_abort(sb, message...) __ext4_abort(sb, __func__, \
1783 __LINE__, ## message)
1784 extern void __ext4_warning(struct super_block *, const char *, unsigned int,
1785 const char *, ...)
1786 __attribute__ ((format (printf, 4, 5)));
1787 #define ext4_warning(sb, message...) __ext4_warning(sb, __func__, \
1788 __LINE__, ## message)
1789 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1790 __attribute__ ((format (printf, 3, 4)));
1791 extern void __ext4_grp_locked_error(const char *, unsigned int, \
1792 struct super_block *, ext4_group_t, \
1793 unsigned long, ext4_fsblk_t, \
1794 const char *, ...)
1795 __attribute__ ((format (printf, 7, 8)));
1796 #define ext4_grp_locked_error(sb, grp, message...) \
1797 __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1798 extern void ext4_update_dynamic_rev(struct super_block *sb);
1799 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1800 __u32 compat);
1801 extern int ext4_update_rocompat_feature(handle_t *handle,
1802 struct super_block *sb, __u32 rocompat);
1803 extern int ext4_update_incompat_feature(handle_t *handle,
1804 struct super_block *sb, __u32 incompat);
1805 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1806 struct ext4_group_desc *bg);
1807 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1808 struct ext4_group_desc *bg);
1809 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1810 struct ext4_group_desc *bg);
1811 extern __u32 ext4_free_blks_count(struct super_block *sb,
1812 struct ext4_group_desc *bg);
1813 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1814 struct ext4_group_desc *bg);
1815 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1816 struct ext4_group_desc *bg);
1817 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1818 struct ext4_group_desc *bg);
1819 extern void ext4_block_bitmap_set(struct super_block *sb,
1820 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1821 extern void ext4_inode_bitmap_set(struct super_block *sb,
1822 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1823 extern void ext4_inode_table_set(struct super_block *sb,
1824 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1825 extern void ext4_free_blks_set(struct super_block *sb,
1826 struct ext4_group_desc *bg, __u32 count);
1827 extern void ext4_free_inodes_set(struct super_block *sb,
1828 struct ext4_group_desc *bg, __u32 count);
1829 extern void ext4_used_dirs_set(struct super_block *sb,
1830 struct ext4_group_desc *bg, __u32 count);
1831 extern void ext4_itable_unused_set(struct super_block *sb,
1832 struct ext4_group_desc *bg, __u32 count);
1833 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1834 struct ext4_group_desc *gdp);
1835 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1836 struct ext4_group_desc *gdp);
1837
1838 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1839 {
1840 return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1841 le32_to_cpu(es->s_blocks_count_lo);
1842 }
1843
1844 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1845 {
1846 return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1847 le32_to_cpu(es->s_r_blocks_count_lo);
1848 }
1849
1850 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1851 {
1852 return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1853 le32_to_cpu(es->s_free_blocks_count_lo);
1854 }
1855
1856 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1857 ext4_fsblk_t blk)
1858 {
1859 es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1860 es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1861 }
1862
1863 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1864 ext4_fsblk_t blk)
1865 {
1866 es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1867 es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1868 }
1869
1870 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1871 ext4_fsblk_t blk)
1872 {
1873 es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1874 es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1875 }
1876
1877 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1878 {
1879 if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1880 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1881 le32_to_cpu(raw_inode->i_size_lo);
1882 else
1883 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1884 }
1885
1886 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1887 {
1888 raw_inode->i_size_lo = cpu_to_le32(i_size);
1889 raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1890 }
1891
1892 static inline
1893 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1894 ext4_group_t group)
1895 {
1896 struct ext4_group_info ***grp_info;
1897 long indexv, indexh;
1898 grp_info = EXT4_SB(sb)->s_group_info;
1899 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1900 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1901 return grp_info[indexv][indexh];
1902 }
1903
1904 /*
1905 * Reading s_groups_count requires using smp_rmb() afterwards. See
1906 * the locking protocol documented in the comments of ext4_group_add()
1907 * in resize.c
1908 */
1909 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
1910 {
1911 ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
1912
1913 smp_rmb();
1914 return ngroups;
1915 }
1916
1917 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1918 ext4_group_t block_group)
1919 {
1920 return block_group >> sbi->s_log_groups_per_flex;
1921 }
1922
1923 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1924 {
1925 return 1 << sbi->s_log_groups_per_flex;
1926 }
1927
1928 #define ext4_std_error(sb, errno) \
1929 do { \
1930 if ((errno)) \
1931 __ext4_std_error((sb), __func__, __LINE__, (errno)); \
1932 } while (0)
1933
1934 #ifdef CONFIG_SMP
1935 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1936 * counters. So we need to make sure we have free blocks more
1937 * than percpu_counter_batch * nr_cpu_ids. Also add a window of 4 times.
1938 */
1939 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1940 #else
1941 #define EXT4_FREEBLOCKS_WATERMARK 0
1942 #endif
1943
1944 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1945 {
1946 /*
1947 * XXX: replace with spinlock if seen contended -bzzz
1948 */
1949 down_write(&EXT4_I(inode)->i_data_sem);
1950 if (newsize > EXT4_I(inode)->i_disksize)
1951 EXT4_I(inode)->i_disksize = newsize;
1952 up_write(&EXT4_I(inode)->i_data_sem);
1953 return ;
1954 }
1955
1956 struct ext4_group_info {
1957 unsigned long bb_state;
1958 struct rb_root bb_free_root;
1959 ext4_grpblk_t bb_first_free; /* first free block */
1960 ext4_grpblk_t bb_free; /* total free blocks */
1961 ext4_grpblk_t bb_fragments; /* nr of freespace fragments */
1962 ext4_grpblk_t bb_largest_free_order;/* order of largest frag in BG */
1963 struct list_head bb_prealloc_list;
1964 #ifdef DOUBLE_CHECK
1965 void *bb_bitmap;
1966 #endif
1967 struct rw_semaphore alloc_sem;
1968 ext4_grpblk_t bb_counters[]; /* Nr of free power-of-two-block
1969 * regions, index is order.
1970 * bb_counters[3] = 5 means
1971 * 5 free 8-block regions. */
1972 };
1973
1974 #define EXT4_GROUP_INFO_NEED_INIT_BIT 0
1975
1976 #define EXT4_MB_GRP_NEED_INIT(grp) \
1977 (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1978
1979 #define EXT4_MAX_CONTENTION 8
1980 #define EXT4_CONTENTION_THRESHOLD 2
1981
1982 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
1983 ext4_group_t group)
1984 {
1985 return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
1986 }
1987
1988 /*
1989 * Returns true if the filesystem is busy enough that attempts to
1990 * access the block group locks has run into contention.
1991 */
1992 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
1993 {
1994 return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
1995 }
1996
1997 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1998 {
1999 spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2000 if (spin_trylock(lock))
2001 /*
2002 * We're able to grab the lock right away, so drop the
2003 * lock contention counter.
2004 */
2005 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2006 else {
2007 /*
2008 * The lock is busy, so bump the contention counter,
2009 * and then wait on the spin lock.
2010 */
2011 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2012 EXT4_MAX_CONTENTION);
2013 spin_lock(lock);
2014 }
2015 }
2016
2017 static inline void ext4_unlock_group(struct super_block *sb,
2018 ext4_group_t group)
2019 {
2020 spin_unlock(ext4_group_lock_ptr(sb, group));
2021 }
2022
2023 static inline void ext4_mark_super_dirty(struct super_block *sb)
2024 {
2025 if (EXT4_SB(sb)->s_journal == NULL)
2026 sb->s_dirt =1;
2027 }
2028
2029 /*
2030 * Inodes and files operations
2031 */
2032
2033 /* dir.c */
2034 extern const struct file_operations ext4_dir_operations;
2035
2036 /* file.c */
2037 extern const struct inode_operations ext4_file_inode_operations;
2038 extern const struct file_operations ext4_file_operations;
2039 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2040
2041 /* namei.c */
2042 extern const struct inode_operations ext4_dir_inode_operations;
2043 extern const struct inode_operations ext4_special_inode_operations;
2044 extern struct dentry *ext4_get_parent(struct dentry *child);
2045
2046 /* symlink.c */
2047 extern const struct inode_operations ext4_symlink_inode_operations;
2048 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2049
2050 /* block_validity */
2051 extern void ext4_release_system_zone(struct super_block *sb);
2052 extern int ext4_setup_system_zone(struct super_block *sb);
2053 extern int __init ext4_init_system_zone(void);
2054 extern void ext4_exit_system_zone(void);
2055 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2056 ext4_fsblk_t start_blk,
2057 unsigned int count);
2058
2059 /* extents.c */
2060 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2061 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2062 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2063 int chunk);
2064 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2065 struct ext4_map_blocks *map, int flags);
2066 extern void ext4_ext_truncate(struct inode *);
2067 extern void ext4_ext_init(struct super_block *);
2068 extern void ext4_ext_release(struct super_block *);
2069 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2070 loff_t len);
2071 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2072 ssize_t len);
2073 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2074 struct ext4_map_blocks *map, int flags);
2075 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2076 __u64 start, __u64 len);
2077 /* move_extent.c */
2078 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2079 __u64 start_orig, __u64 start_donor,
2080 __u64 len, __u64 *moved_len);
2081
2082 /* page-io.c */
2083 extern int __init ext4_init_pageio(void);
2084 extern void ext4_exit_pageio(void);
2085 extern void ext4_ioend_wait(struct inode *);
2086 extern void ext4_free_io_end(ext4_io_end_t *io);
2087 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2088 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2089 extern void ext4_io_submit(struct ext4_io_submit *io);
2090 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2091 struct page *page,
2092 int len,
2093 struct writeback_control *wbc);
2094
2095 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2096 enum ext4_state_bits {
2097 BH_Uninit /* blocks are allocated but uninitialized on disk */
2098 = BH_JBDPrivateStart,
2099 };
2100
2101 BUFFER_FNS(Uninit, uninit)
2102 TAS_BUFFER_FNS(Uninit, uninit)
2103
2104 /*
2105 * Add new method to test wether block and inode bitmaps are properly
2106 * initialized. With uninit_bg reading the block from disk is not enough
2107 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2108 */
2109 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2110
2111 static inline int bitmap_uptodate(struct buffer_head *bh)
2112 {
2113 return (buffer_uptodate(bh) &&
2114 test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2115 }
2116 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2117 {
2118 set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2119 }
2120
2121 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2122
2123 /* For ioend & aio unwritten conversion wait queues */
2124 #define EXT4_WQ_HASH_SZ 37
2125 #define ext4_ioend_wq(v) (&ext4__ioend_wq[((unsigned long)(v)) %\
2126 EXT4_WQ_HASH_SZ])
2127 #define ext4_aio_mutex(v) (&ext4__aio_mutex[((unsigned long)(v)) %\
2128 EXT4_WQ_HASH_SZ])
2129 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2130 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2131
2132 #endif /* __KERNEL__ */
2133
2134 #endif /* _EXT4_H */
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