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kvm tools, setup: Create private directory
[linux-2.6/next.git] / fs / ext4 / ext4.h
blob1921392cd7085d4b2679ea398979ec78d17d2099
1 /*
2 * ext4.h
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/include/linux/minix_fs.h
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 */
15
16 #ifndef _EXT4_H
17 #define _EXT4_H
18
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/wait.h>
30 #include <linux/blockgroup_lock.h>
31 #include <linux/percpu_counter.h>
32 #ifdef __KERNEL__
33 #include <linux/compat.h>
34 #endif
35
36 /*
37 * The fourth extended filesystem constants/structures
38 */
39
40 /*
41 * Define EXT4FS_DEBUG to produce debug messages
42 */
43 #undef EXT4FS_DEBUG
44
45 /*
46 * Debug code
47 */
48 #ifdef EXT4FS_DEBUG
49 #define ext4_debug(f, a...) \
50 do { \
51 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:", \
52 __FILE__, __LINE__, __func__); \
53 printk(KERN_DEBUG f, ## a); \
54 } while (0)
55 #else
56 #define ext4_debug(f, a...) do {} while (0)
57 #endif
58
59 #define EXT4_ERROR_INODE(inode, fmt, a...) \
60 ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
61
62 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...) \
63 ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
64
65 #define EXT4_ERROR_FILE(file, block, fmt, a...) \
66 ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
67
68 /* data type for block offset of block group */
69 typedef int ext4_grpblk_t;
70
71 /* data type for filesystem-wide blocks number */
72 typedef unsigned long long ext4_fsblk_t;
73
74 /* data type for file logical block number */
75 typedef __u32 ext4_lblk_t;
76
77 /* data type for block group number */
78 typedef unsigned int ext4_group_t;
79
80 /*
81 * Flags used in mballoc's allocation_context flags field.
82 *
83 * Also used to show what's going on for debugging purposes when the
84 * flag field is exported via the traceport interface
85 */
86
87 /* prefer goal again. length */
88 #define EXT4_MB_HINT_MERGE 0x0001
89 /* blocks already reserved */
90 #define EXT4_MB_HINT_RESERVED 0x0002
91 /* metadata is being allocated */
92 #define EXT4_MB_HINT_METADATA 0x0004
93 /* first blocks in the file */
94 #define EXT4_MB_HINT_FIRST 0x0008
95 /* search for the best chunk */
96 #define EXT4_MB_HINT_BEST 0x0010
97 /* data is being allocated */
98 #define EXT4_MB_HINT_DATA 0x0020
99 /* don't preallocate (for tails) */
100 #define EXT4_MB_HINT_NOPREALLOC 0x0040
101 /* allocate for locality group */
102 #define EXT4_MB_HINT_GROUP_ALLOC 0x0080
103 /* allocate goal blocks or none */
104 #define EXT4_MB_HINT_GOAL_ONLY 0x0100
105 /* goal is meaningful */
106 #define EXT4_MB_HINT_TRY_GOAL 0x0200
107 /* blocks already pre-reserved by delayed allocation */
108 #define EXT4_MB_DELALLOC_RESERVED 0x0400
109 /* We are doing stream allocation */
110 #define EXT4_MB_STREAM_ALLOC 0x0800
111 /* Use reserved root blocks if needed */
112 #define EXT4_MB_USE_ROOT_BLOCKS 0x1000
113
114 struct ext4_allocation_request {
115 /* target inode for block we're allocating */
116 struct inode *inode;
117 /* how many blocks we want to allocate */
118 unsigned int len;
119 /* logical block in target inode */
120 ext4_lblk_t logical;
121 /* the closest logical allocated block to the left */
122 ext4_lblk_t lleft;
123 /* the closest logical allocated block to the right */
124 ext4_lblk_t lright;
125 /* phys. target (a hint) */
126 ext4_fsblk_t goal;
127 /* phys. block for the closest logical allocated block to the left */
128 ext4_fsblk_t pleft;
129 /* phys. block for the closest logical allocated block to the right */
130 ext4_fsblk_t pright;
131 /* flags. see above EXT4_MB_HINT_* */
132 unsigned int flags;
133 };
134
135 /*
136 * Logical to physical block mapping, used by ext4_map_blocks()
137 *
138 * This structure is used to pass requests into ext4_map_blocks() as
139 * well as to store the information returned by ext4_map_blocks(). It
140 * takes less room on the stack than a struct buffer_head.
141 */
142 #define EXT4_MAP_NEW (1 << BH_New)
143 #define EXT4_MAP_MAPPED (1 << BH_Mapped)
144 #define EXT4_MAP_UNWRITTEN (1 << BH_Unwritten)
145 #define EXT4_MAP_BOUNDARY (1 << BH_Boundary)
146 #define EXT4_MAP_UNINIT (1 << BH_Uninit)
147 #define EXT4_MAP_FLAGS (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
148 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
149 EXT4_MAP_UNINIT)
150
151 struct ext4_map_blocks {
152 ext4_fsblk_t m_pblk;
153 ext4_lblk_t m_lblk;
154 unsigned int m_len;
155 unsigned int m_flags;
156 };
157
158 /*
159 * For delayed allocation tracking
160 */
161 struct mpage_da_data {
162 struct inode *inode;
163 sector_t b_blocknr; /* start block number of extent */
164 size_t b_size; /* size of extent */
165 unsigned long b_state; /* state of the extent */
166 unsigned long first_page, next_page; /* extent of pages */
167 struct writeback_control *wbc;
168 int io_done;
169 int pages_written;
170 int retval;
171 };
172
173 /*
174 * Flags for ext4_io_end->flags
175 */
176 #define EXT4_IO_END_UNWRITTEN 0x0001
177 #define EXT4_IO_END_ERROR 0x0002
178
179 struct ext4_io_page {
180 struct page *p_page;
181 atomic_t p_count;
182 };
183
184 #define MAX_IO_PAGES 128
185
186 typedef struct ext4_io_end {
187 struct list_head list; /* per-file finished IO list */
188 struct inode *inode; /* file being written to */
189 unsigned int flag; /* unwritten or not */
190 struct page *page; /* page struct for buffer write */
191 loff_t offset; /* offset in the file */
192 ssize_t size; /* size of the extent */
193 struct work_struct work; /* data work queue */
194 struct kiocb *iocb; /* iocb struct for AIO */
195 int result; /* error value for AIO */
196 int num_io_pages;
197 struct ext4_io_page *pages[MAX_IO_PAGES];
198 } ext4_io_end_t;
199
200 struct ext4_io_submit {
201 int io_op;
202 struct bio *io_bio;
203 ext4_io_end_t *io_end;
204 struct ext4_io_page *io_page;
205 sector_t io_next_block;
206 };
207
208 /*
209 * Special inodes numbers
210 */
211 #define EXT4_BAD_INO 1 /* Bad blocks inode */
212 #define EXT4_ROOT_INO 2 /* Root inode */
213 #define EXT4_USR_QUOTA_INO 3 /* User quota inode */
214 #define EXT4_GRP_QUOTA_INO 4 /* Group quota inode */
215 #define EXT4_BOOT_LOADER_INO 5 /* Boot loader inode */
216 #define EXT4_UNDEL_DIR_INO 6 /* Undelete directory inode */
217 #define EXT4_RESIZE_INO 7 /* Reserved group descriptors inode */
218 #define EXT4_JOURNAL_INO 8 /* Journal inode */
219
220 /* First non-reserved inode for old ext4 filesystems */
221 #define EXT4_GOOD_OLD_FIRST_INO 11
222
223 /*
224 * Maximal count of links to a file
225 */
226 #define EXT4_LINK_MAX 65000
227
228 /*
229 * Macro-instructions used to manage several block sizes
230 */
231 #define EXT4_MIN_BLOCK_SIZE 1024
232 #define EXT4_MAX_BLOCK_SIZE 65536
233 #define EXT4_MIN_BLOCK_LOG_SIZE 10
234 #define EXT4_MAX_BLOCK_LOG_SIZE 16
235 #ifdef __KERNEL__
236 # define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize)
237 #else
238 # define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
239 #endif
240 #define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
241 #ifdef __KERNEL__
242 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
243 #else
244 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
245 #endif
246 #ifdef __KERNEL__
247 #define EXT4_ADDR_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_addr_per_block_bits)
248 #define EXT4_INODE_SIZE(s) (EXT4_SB(s)->s_inode_size)
249 #define EXT4_FIRST_INO(s) (EXT4_SB(s)->s_first_ino)
250 #else
251 #define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
252 EXT4_GOOD_OLD_INODE_SIZE : \
253 (s)->s_inode_size)
254 #define EXT4_FIRST_INO(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
255 EXT4_GOOD_OLD_FIRST_INO : \
256 (s)->s_first_ino)
257 #endif
258 #define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
259
260 /*
261 * Structure of a blocks group descriptor
262 */
263 struct ext4_group_desc
264 {
265 __le32 bg_block_bitmap_lo; /* Blocks bitmap block */
266 __le32 bg_inode_bitmap_lo; /* Inodes bitmap block */
267 __le32 bg_inode_table_lo; /* Inodes table block */
268 __le16 bg_free_blocks_count_lo;/* Free blocks count */
269 __le16 bg_free_inodes_count_lo;/* Free inodes count */
270 __le16 bg_used_dirs_count_lo; /* Directories count */
271 __le16 bg_flags; /* EXT4_BG_flags (INODE_UNINIT, etc) */
272 __u32 bg_reserved[2]; /* Likely block/inode bitmap checksum */
273 __le16 bg_itable_unused_lo; /* Unused inodes count */
274 __le16 bg_checksum; /* crc16(sb_uuid+group+desc) */
275 __le32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
276 __le32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
277 __le32 bg_inode_table_hi; /* Inodes table block MSB */
278 __le16 bg_free_blocks_count_hi;/* Free blocks count MSB */
279 __le16 bg_free_inodes_count_hi;/* Free inodes count MSB */
280 __le16 bg_used_dirs_count_hi; /* Directories count MSB */
281 __le16 bg_itable_unused_hi; /* Unused inodes count MSB */
282 __u32 bg_reserved2[3];
283 };
284
285 /*
286 * Structure of a flex block group info
287 */
288
289 struct flex_groups {
290 atomic_t free_inodes;
291 atomic_t free_blocks;
292 atomic_t used_dirs;
293 };
294
295 #define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */
296 #define EXT4_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */
297 #define EXT4_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
298
299 /*
300 * Macro-instructions used to manage group descriptors
301 */
302 #define EXT4_MIN_DESC_SIZE 32
303 #define EXT4_MIN_DESC_SIZE_64BIT 64
304 #define EXT4_MAX_DESC_SIZE EXT4_MIN_BLOCK_SIZE
305 #define EXT4_DESC_SIZE(s) (EXT4_SB(s)->s_desc_size)
306 #ifdef __KERNEL__
307 # define EXT4_BLOCKS_PER_GROUP(s) (EXT4_SB(s)->s_blocks_per_group)
308 # define EXT4_DESC_PER_BLOCK(s) (EXT4_SB(s)->s_desc_per_block)
309 # define EXT4_INODES_PER_GROUP(s) (EXT4_SB(s)->s_inodes_per_group)
310 # define EXT4_DESC_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_desc_per_block_bits)
311 #else
312 # define EXT4_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
313 # define EXT4_DESC_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
314 # define EXT4_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
315 #endif
316
317 /*
318 * Constants relative to the data blocks
319 */
320 #define EXT4_NDIR_BLOCKS 12
321 #define EXT4_IND_BLOCK EXT4_NDIR_BLOCKS
322 #define EXT4_DIND_BLOCK (EXT4_IND_BLOCK + 1)
323 #define EXT4_TIND_BLOCK (EXT4_DIND_BLOCK + 1)
324 #define EXT4_N_BLOCKS (EXT4_TIND_BLOCK + 1)
325
326 /*
327 * Inode flags
328 */
329 #define EXT4_SECRM_FL 0x00000001 /* Secure deletion */
330 #define EXT4_UNRM_FL 0x00000002 /* Undelete */
331 #define EXT4_COMPR_FL 0x00000004 /* Compress file */
332 #define EXT4_SYNC_FL 0x00000008 /* Synchronous updates */
333 #define EXT4_IMMUTABLE_FL 0x00000010 /* Immutable file */
334 #define EXT4_APPEND_FL 0x00000020 /* writes to file may only append */
335 #define EXT4_NODUMP_FL 0x00000040 /* do not dump file */
336 #define EXT4_NOATIME_FL 0x00000080 /* do not update atime */
337 /* Reserved for compression usage... */
338 #define EXT4_DIRTY_FL 0x00000100
339 #define EXT4_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
340 #define EXT4_NOCOMPR_FL 0x00000400 /* Don't compress */
341 #define EXT4_ECOMPR_FL 0x00000800 /* Compression error */
342 /* End compression flags --- maybe not all used */
343 #define EXT4_INDEX_FL 0x00001000 /* hash-indexed directory */
344 #define EXT4_IMAGIC_FL 0x00002000 /* AFS directory */
345 #define EXT4_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
346 #define EXT4_NOTAIL_FL 0x00008000 /* file tail should not be merged */
347 #define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
348 #define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
349 #define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
350 #define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
351 #define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */
352 #define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */
353 #define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
354
355 #define EXT4_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */
356 #define EXT4_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */
357
358 /* Flags that should be inherited by new inodes from their parent. */
359 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
360 EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
361 EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
362 EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
363 EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
364
365 /* Flags that are appropriate for regular files (all but dir-specific ones). */
366 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
367
368 /* Flags that are appropriate for non-directories/regular files. */
369 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
370
371 /* Mask out flags that are inappropriate for the given type of inode. */
372 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
373 {
374 if (S_ISDIR(mode))
375 return flags;
376 else if (S_ISREG(mode))
377 return flags & EXT4_REG_FLMASK;
378 else
379 return flags & EXT4_OTHER_FLMASK;
380 }
381
382 /*
383 * Inode flags used for atomic set/get
384 */
385 enum {
386 EXT4_INODE_SECRM = 0, /* Secure deletion */
387 EXT4_INODE_UNRM = 1, /* Undelete */
388 EXT4_INODE_COMPR = 2, /* Compress file */
389 EXT4_INODE_SYNC = 3, /* Synchronous updates */
390 EXT4_INODE_IMMUTABLE = 4, /* Immutable file */
391 EXT4_INODE_APPEND = 5, /* writes to file may only append */
392 EXT4_INODE_NODUMP = 6, /* do not dump file */
393 EXT4_INODE_NOATIME = 7, /* do not update atime */
394 /* Reserved for compression usage... */
395 EXT4_INODE_DIRTY = 8,
396 EXT4_INODE_COMPRBLK = 9, /* One or more compressed clusters */
397 EXT4_INODE_NOCOMPR = 10, /* Don't compress */
398 EXT4_INODE_ECOMPR = 11, /* Compression error */
399 /* End compression flags --- maybe not all used */
400 EXT4_INODE_INDEX = 12, /* hash-indexed directory */
401 EXT4_INODE_IMAGIC = 13, /* AFS directory */
402 EXT4_INODE_JOURNAL_DATA = 14, /* file data should be journaled */
403 EXT4_INODE_NOTAIL = 15, /* file tail should not be merged */
404 EXT4_INODE_DIRSYNC = 16, /* dirsync behaviour (directories only) */
405 EXT4_INODE_TOPDIR = 17, /* Top of directory hierarchies*/
406 EXT4_INODE_HUGE_FILE = 18, /* Set to each huge file */
407 EXT4_INODE_EXTENTS = 19, /* Inode uses extents */
408 EXT4_INODE_EA_INODE = 21, /* Inode used for large EA */
409 EXT4_INODE_EOFBLOCKS = 22, /* Blocks allocated beyond EOF */
410 EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */
411 };
412
413 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
414 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
415 printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
416 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
417
418 /*
419 * Since it's pretty easy to mix up bit numbers and hex values, and we
420 * can't do a compile-time test for ENUM values, we use a run-time
421 * test to make sure that EXT4_XXX_FL is consistent with respect to
422 * EXT4_INODE_XXX. If all is well the printk and BUG_ON will all drop
423 * out so it won't cost any extra space in the compiled kernel image.
424 * But it's important that these values are the same, since we are
425 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
426 * must be consistent with the values of FS_XXX_FL defined in
427 * include/linux/fs.h and the on-disk values found in ext2, ext3, and
428 * ext4 filesystems, and of course the values defined in e2fsprogs.
429 *
430 * It's not paranoia if the Murphy's Law really *is* out to get you. :-)
431 */
432 static inline void ext4_check_flag_values(void)
433 {
434 CHECK_FLAG_VALUE(SECRM);
435 CHECK_FLAG_VALUE(UNRM);
436 CHECK_FLAG_VALUE(COMPR);
437 CHECK_FLAG_VALUE(SYNC);
438 CHECK_FLAG_VALUE(IMMUTABLE);
439 CHECK_FLAG_VALUE(APPEND);
440 CHECK_FLAG_VALUE(NODUMP);
441 CHECK_FLAG_VALUE(NOATIME);
442 CHECK_FLAG_VALUE(DIRTY);
443 CHECK_FLAG_VALUE(COMPRBLK);
444 CHECK_FLAG_VALUE(NOCOMPR);
445 CHECK_FLAG_VALUE(ECOMPR);
446 CHECK_FLAG_VALUE(INDEX);
447 CHECK_FLAG_VALUE(IMAGIC);
448 CHECK_FLAG_VALUE(JOURNAL_DATA);
449 CHECK_FLAG_VALUE(NOTAIL);
450 CHECK_FLAG_VALUE(DIRSYNC);
451 CHECK_FLAG_VALUE(TOPDIR);
452 CHECK_FLAG_VALUE(HUGE_FILE);
453 CHECK_FLAG_VALUE(EXTENTS);
454 CHECK_FLAG_VALUE(EA_INODE);
455 CHECK_FLAG_VALUE(EOFBLOCKS);
456 CHECK_FLAG_VALUE(RESERVED);
457 }
458
459 /* Used to pass group descriptor data when online resize is done */
460 struct ext4_new_group_input {
461 __u32 group; /* Group number for this data */
462 __u64 block_bitmap; /* Absolute block number of block bitmap */
463 __u64 inode_bitmap; /* Absolute block number of inode bitmap */
464 __u64 inode_table; /* Absolute block number of inode table start */
465 __u32 blocks_count; /* Total number of blocks in this group */
466 __u16 reserved_blocks; /* Number of reserved blocks in this group */
467 __u16 unused;
468 };
469
470 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
471 struct compat_ext4_new_group_input {
472 u32 group;
473 compat_u64 block_bitmap;
474 compat_u64 inode_bitmap;
475 compat_u64 inode_table;
476 u32 blocks_count;
477 u16 reserved_blocks;
478 u16 unused;
479 };
480 #endif
481
482 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
483 struct ext4_new_group_data {
484 __u32 group;
485 __u64 block_bitmap;
486 __u64 inode_bitmap;
487 __u64 inode_table;
488 __u32 blocks_count;
489 __u16 reserved_blocks;
490 __u16 unused;
491 __u32 free_blocks_count;
492 };
493
494 /*
495 * Flags used by ext4_map_blocks()
496 */
497 /* Allocate any needed blocks and/or convert an unitialized
498 extent to be an initialized ext4 */
499 #define EXT4_GET_BLOCKS_CREATE 0x0001
500 /* Request the creation of an unitialized extent */
501 #define EXT4_GET_BLOCKS_UNINIT_EXT 0x0002
502 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT (EXT4_GET_BLOCKS_UNINIT_EXT|\
503 EXT4_GET_BLOCKS_CREATE)
504 /* Caller is from the delayed allocation writeout path,
505 so set the magic i_delalloc_reserve_flag after taking the
506 inode allocation semaphore for */
507 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE 0x0004
508 /* caller is from the direct IO path, request to creation of an
509 unitialized extents if not allocated, split the uninitialized
510 extent if blocks has been preallocated already*/
511 #define EXT4_GET_BLOCKS_PRE_IO 0x0008
512 #define EXT4_GET_BLOCKS_CONVERT 0x0010
513 #define EXT4_GET_BLOCKS_IO_CREATE_EXT (EXT4_GET_BLOCKS_PRE_IO|\
514 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
515 /* Convert extent to initialized after IO complete */
516 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT (EXT4_GET_BLOCKS_CONVERT|\
517 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
518 /* Punch out blocks of an extent */
519 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT 0x0020
520 /* Don't normalize allocation size (used for fallocate) */
521 #define EXT4_GET_BLOCKS_NO_NORMALIZE 0x0040
522
523 /*
524 * Flags used by ext4_free_blocks
525 */
526 #define EXT4_FREE_BLOCKS_METADATA 0x0001
527 #define EXT4_FREE_BLOCKS_FORGET 0x0002
528 #define EXT4_FREE_BLOCKS_VALIDATED 0x0004
529
530 /*
531 * ioctl commands
532 */
533 #define EXT4_IOC_GETFLAGS FS_IOC_GETFLAGS
534 #define EXT4_IOC_SETFLAGS FS_IOC_SETFLAGS
535 #define EXT4_IOC_GETVERSION _IOR('f', 3, long)
536 #define EXT4_IOC_SETVERSION _IOW('f', 4, long)
537 #define EXT4_IOC_GETVERSION_OLD FS_IOC_GETVERSION
538 #define EXT4_IOC_SETVERSION_OLD FS_IOC_SETVERSION
539 #ifdef CONFIG_JBD2_DEBUG
540 #define EXT4_IOC_WAIT_FOR_READONLY _IOR('f', 99, long)
541 #endif
542 #define EXT4_IOC_GETRSVSZ _IOR('f', 5, long)
543 #define EXT4_IOC_SETRSVSZ _IOW('f', 6, long)
544 #define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
545 #define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
546 #define EXT4_IOC_MIGRATE _IO('f', 9)
547 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
548 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
549 #define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12)
550 #define EXT4_IOC_MOVE_EXT _IOWR('f', 15, struct move_extent)
551
552 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
553 /*
554 * ioctl commands in 32 bit emulation
555 */
556 #define EXT4_IOC32_GETFLAGS FS_IOC32_GETFLAGS
557 #define EXT4_IOC32_SETFLAGS FS_IOC32_SETFLAGS
558 #define EXT4_IOC32_GETVERSION _IOR('f', 3, int)
559 #define EXT4_IOC32_SETVERSION _IOW('f', 4, int)
560 #define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int)
561 #define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int)
562 #define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int)
563 #define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input)
564 #ifdef CONFIG_JBD2_DEBUG
565 #define EXT4_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int)
566 #endif
567 #define EXT4_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION
568 #define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
569 #endif
570
571 /* Max physical block we can address w/o extents */
572 #define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF
573
574 /*
575 * Structure of an inode on the disk
576 */
577 struct ext4_inode {
578 __le16 i_mode; /* File mode */
579 __le16 i_uid; /* Low 16 bits of Owner Uid */
580 __le32 i_size_lo; /* Size in bytes */
581 __le32 i_atime; /* Access time */
582 __le32 i_ctime; /* Inode Change time */
583 __le32 i_mtime; /* Modification time */
584 __le32 i_dtime; /* Deletion Time */
585 __le16 i_gid; /* Low 16 bits of Group Id */
586 __le16 i_links_count; /* Links count */
587 __le32 i_blocks_lo; /* Blocks count */
588 __le32 i_flags; /* File flags */
589 union {
590 struct {
591 __le32 l_i_version;
592 } linux1;
593 struct {
594 __u32 h_i_translator;
595 } hurd1;
596 struct {
597 __u32 m_i_reserved1;
598 } masix1;
599 } osd1; /* OS dependent 1 */
600 __le32 i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
601 __le32 i_generation; /* File version (for NFS) */
602 __le32 i_file_acl_lo; /* File ACL */
603 __le32 i_size_high;
604 __le32 i_obso_faddr; /* Obsoleted fragment address */
605 union {
606 struct {
607 __le16 l_i_blocks_high; /* were l_i_reserved1 */
608 __le16 l_i_file_acl_high;
609 __le16 l_i_uid_high; /* these 2 fields */
610 __le16 l_i_gid_high; /* were reserved2[0] */
611 __u32 l_i_reserved2;
612 } linux2;
613 struct {
614 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
615 __u16 h_i_mode_high;
616 __u16 h_i_uid_high;
617 __u16 h_i_gid_high;
618 __u32 h_i_author;
619 } hurd2;
620 struct {
621 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
622 __le16 m_i_file_acl_high;
623 __u32 m_i_reserved2[2];
624 } masix2;
625 } osd2; /* OS dependent 2 */
626 __le16 i_extra_isize;
627 __le16 i_pad1;
628 __le32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
629 __le32 i_mtime_extra; /* extra Modification time(nsec << 2 | epoch) */
630 __le32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
631 __le32 i_crtime; /* File Creation time */
632 __le32 i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
633 __le32 i_version_hi; /* high 32 bits for 64-bit version */
634 };
635
636 struct move_extent {
637 __u32 reserved; /* should be zero */
638 __u32 donor_fd; /* donor file descriptor */
639 __u64 orig_start; /* logical start offset in block for orig */
640 __u64 donor_start; /* logical start offset in block for donor */
641 __u64 len; /* block length to be moved */
642 __u64 moved_len; /* moved block length */
643 };
644
645 #define EXT4_EPOCH_BITS 2
646 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
647 #define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS)
648
649 /*
650 * Extended fields will fit into an inode if the filesystem was formatted
651 * with large inodes (-I 256 or larger) and there are not currently any EAs
652 * consuming all of the available space. For new inodes we always reserve
653 * enough space for the kernel's known extended fields, but for inodes
654 * created with an old kernel this might not have been the case. None of
655 * the extended inode fields is critical for correct filesystem operation.
656 * This macro checks if a certain field fits in the inode. Note that
657 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
658 */
659 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field) \
660 ((offsetof(typeof(*ext4_inode), field) + \
661 sizeof((ext4_inode)->field)) \
662 <= (EXT4_GOOD_OLD_INODE_SIZE + \
663 (einode)->i_extra_isize)) \
664
665 static inline __le32 ext4_encode_extra_time(struct timespec *time)
666 {
667 return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
668 (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
669 ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
670 }
671
672 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
673 {
674 if (sizeof(time->tv_sec) > 4)
675 time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
676 << 32;
677 time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
678 }
679
680 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode) \
681 do { \
682 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \
683 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
684 (raw_inode)->xtime ## _extra = \
685 ext4_encode_extra_time(&(inode)->xtime); \
686 } while (0)
687
688 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \
689 do { \
690 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
691 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec); \
692 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
693 (raw_inode)->xtime ## _extra = \
694 ext4_encode_extra_time(&(einode)->xtime); \
695 } while (0)
696
697 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode) \
698 do { \
699 (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime); \
700 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
701 ext4_decode_extra_time(&(inode)->xtime, \
702 raw_inode->xtime ## _extra); \
703 else \
704 (inode)->xtime.tv_nsec = 0; \
705 } while (0)
706
707 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode) \
708 do { \
709 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
710 (einode)->xtime.tv_sec = \
711 (signed)le32_to_cpu((raw_inode)->xtime); \
712 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
713 ext4_decode_extra_time(&(einode)->xtime, \
714 raw_inode->xtime ## _extra); \
715 else \
716 (einode)->xtime.tv_nsec = 0; \
717 } while (0)
718
719 #define i_disk_version osd1.linux1.l_i_version
720
721 #if defined(__KERNEL__) || defined(__linux__)
722 #define i_reserved1 osd1.linux1.l_i_reserved1
723 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
724 #define i_blocks_high osd2.linux2.l_i_blocks_high
725 #define i_uid_low i_uid
726 #define i_gid_low i_gid
727 #define i_uid_high osd2.linux2.l_i_uid_high
728 #define i_gid_high osd2.linux2.l_i_gid_high
729 #define i_reserved2 osd2.linux2.l_i_reserved2
730
731 #elif defined(__GNU__)
732
733 #define i_translator osd1.hurd1.h_i_translator
734 #define i_uid_high osd2.hurd2.h_i_uid_high
735 #define i_gid_high osd2.hurd2.h_i_gid_high
736 #define i_author osd2.hurd2.h_i_author
737
738 #elif defined(__masix__)
739
740 #define i_reserved1 osd1.masix1.m_i_reserved1
741 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
742 #define i_reserved2 osd2.masix2.m_i_reserved2
743
744 #endif /* defined(__KERNEL__) || defined(__linux__) */
745
746 /*
747 * storage for cached extent
748 * If ec_len == 0, then the cache is invalid.
749 * If ec_start == 0, then the cache represents a gap (null mapping)
750 */
751 struct ext4_ext_cache {
752 ext4_fsblk_t ec_start;
753 ext4_lblk_t ec_block;
754 __u32 ec_len; /* must be 32bit to return holes */
755 };
756
757 /*
758 * fourth extended file system inode data in memory
759 */
760 struct ext4_inode_info {
761 __le32 i_data[15]; /* unconverted */
762 __u32 i_dtime;
763 ext4_fsblk_t i_file_acl;
764
765 /*
766 * i_block_group is the number of the block group which contains
767 * this file's inode. Constant across the lifetime of the inode,
768 * it is ued for making block allocation decisions - we try to
769 * place a file's data blocks near its inode block, and new inodes
770 * near to their parent directory's inode.
771 */
772 ext4_group_t i_block_group;
773 ext4_lblk_t i_dir_start_lookup;
774 #if (BITS_PER_LONG < 64)
775 unsigned long i_state_flags; /* Dynamic state flags */
776 #endif
777 unsigned long i_flags;
778
779 #ifdef CONFIG_EXT4_FS_XATTR
780 /*
781 * Extended attributes can be read independently of the main file
782 * data. Taking i_mutex even when reading would cause contention
783 * between readers of EAs and writers of regular file data, so
784 * instead we synchronize on xattr_sem when reading or changing
785 * EAs.
786 */
787 struct rw_semaphore xattr_sem;
788 #endif
789
790 struct list_head i_orphan; /* unlinked but open inodes */
791
792 /*
793 * i_disksize keeps track of what the inode size is ON DISK, not
794 * in memory. During truncate, i_size is set to the new size by
795 * the VFS prior to calling ext4_truncate(), but the filesystem won't
796 * set i_disksize to 0 until the truncate is actually under way.
797 *
798 * The intent is that i_disksize always represents the blocks which
799 * are used by this file. This allows recovery to restart truncate
800 * on orphans if we crash during truncate. We actually write i_disksize
801 * into the on-disk inode when writing inodes out, instead of i_size.
802 *
803 * The only time when i_disksize and i_size may be different is when
804 * a truncate is in progress. The only things which change i_disksize
805 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
806 */
807 loff_t i_disksize;
808
809 /*
810 * i_data_sem is for serialising ext4_truncate() against
811 * ext4_getblock(). In the 2.4 ext2 design, great chunks of inode's
812 * data tree are chopped off during truncate. We can't do that in
813 * ext4 because whenever we perform intermediate commits during
814 * truncate, the inode and all the metadata blocks *must* be in a
815 * consistent state which allows truncation of the orphans to restart
816 * during recovery. Hence we must fix the get_block-vs-truncate race
817 * by other means, so we have i_data_sem.
818 */
819 struct rw_semaphore i_data_sem;
820 struct inode vfs_inode;
821 struct jbd2_inode *jinode;
822
823 struct ext4_ext_cache i_cached_extent;
824 /*
825 * File creation time. Its function is same as that of
826 * struct timespec i_{a,c,m}time in the generic inode.
827 */
828 struct timespec i_crtime;
829
830 /* mballoc */
831 struct list_head i_prealloc_list;
832 spinlock_t i_prealloc_lock;
833
834 /* ialloc */
835 ext4_group_t i_last_alloc_group;
836
837 /* allocation reservation info for delalloc */
838 unsigned int i_reserved_data_blocks;
839 unsigned int i_reserved_meta_blocks;
840 unsigned int i_allocated_meta_blocks;
841 ext4_lblk_t i_da_metadata_calc_last_lblock;
842 int i_da_metadata_calc_len;
843
844 /* on-disk additional length */
845 __u16 i_extra_isize;
846
847 #ifdef CONFIG_QUOTA
848 /* quota space reservation, managed internally by quota code */
849 qsize_t i_reserved_quota;
850 #endif
851
852 /* completed IOs that might need unwritten extents handling */
853 struct list_head i_completed_io_list;
854 spinlock_t i_completed_io_lock;
855 atomic_t i_ioend_count; /* Number of outstanding io_end structs */
856 /* current io_end structure for async DIO write*/
857 ext4_io_end_t *cur_aio_dio;
858 atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
859
860 spinlock_t i_block_reservation_lock;
861
862 /*
863 * Transactions that contain inode's metadata needed to complete
864 * fsync and fdatasync, respectively.
865 */
866 tid_t i_sync_tid;
867 tid_t i_datasync_tid;
868 };
869
870 /*
871 * File system states
872 */
873 #define EXT4_VALID_FS 0x0001 /* Unmounted cleanly */
874 #define EXT4_ERROR_FS 0x0002 /* Errors detected */
875 #define EXT4_ORPHAN_FS 0x0004 /* Orphans being recovered */
876
877 /*
878 * Misc. filesystem flags
879 */
880 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
881 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
882 #define EXT2_FLAGS_TEST_FILESYS 0x0004 /* to test development code */
883
884 /*
885 * Mount flags
886 */
887 #define EXT4_MOUNT_OLDALLOC 0x00002 /* Don't use the new Orlov allocator */
888 #define EXT4_MOUNT_GRPID 0x00004 /* Create files with directory's group */
889 #define EXT4_MOUNT_DEBUG 0x00008 /* Some debugging messages */
890 #define EXT4_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */
891 #define EXT4_MOUNT_ERRORS_RO 0x00020 /* Remount fs ro on errors */
892 #define EXT4_MOUNT_ERRORS_PANIC 0x00040 /* Panic on errors */
893 #define EXT4_MOUNT_MINIX_DF 0x00080 /* Mimics the Minix statfs */
894 #define EXT4_MOUNT_NOLOAD 0x00100 /* Don't use existing journal*/
895 #define EXT4_MOUNT_DATA_FLAGS 0x00C00 /* Mode for data writes: */
896 #define EXT4_MOUNT_JOURNAL_DATA 0x00400 /* Write data to journal */
897 #define EXT4_MOUNT_ORDERED_DATA 0x00800 /* Flush data before commit */
898 #define EXT4_MOUNT_WRITEBACK_DATA 0x00C00 /* No data ordering */
899 #define EXT4_MOUNT_UPDATE_JOURNAL 0x01000 /* Update the journal format */
900 #define EXT4_MOUNT_NO_UID32 0x02000 /* Disable 32-bit UIDs */
901 #define EXT4_MOUNT_XATTR_USER 0x04000 /* Extended user attributes */
902 #define EXT4_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */
903 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */
904 #define EXT4_MOUNT_BARRIER 0x20000 /* Use block barriers */
905 #define EXT4_MOUNT_QUOTA 0x80000 /* Some quota option set */
906 #define EXT4_MOUNT_USRQUOTA 0x100000 /* "old" user quota */
907 #define EXT4_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */
908 #define EXT4_MOUNT_DIOREAD_NOLOCK 0x400000 /* Enable support for dio read nolocking */
909 #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */
910 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
911 #define EXT4_MOUNT_I_VERSION 0x2000000 /* i_version support */
912 #define EXT4_MOUNT_MBLK_IO_SUBMIT 0x4000000 /* multi-block io submits */
913 #define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */
914 #define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */
915 #define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */
916 #define EXT4_MOUNT_DISCARD 0x40000000 /* Issue DISCARD requests */
917 #define EXT4_MOUNT_INIT_INODE_TABLE 0x80000000 /* Initialize uninitialized itables */
918
919 #define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \
920 ~EXT4_MOUNT_##opt
921 #define set_opt(sb, opt) EXT4_SB(sb)->s_mount_opt |= \
922 EXT4_MOUNT_##opt
923 #define test_opt(sb, opt) (EXT4_SB(sb)->s_mount_opt & \
924 EXT4_MOUNT_##opt)
925
926 #define clear_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 &= \
927 ~EXT4_MOUNT2_##opt
928 #define set_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 |= \
929 EXT4_MOUNT2_##opt
930 #define test_opt2(sb, opt) (EXT4_SB(sb)->s_mount_opt2 & \
931 EXT4_MOUNT2_##opt)
932
933 #define ext4_set_bit __test_and_set_bit_le
934 #define ext4_set_bit_atomic ext2_set_bit_atomic
935 #define ext4_clear_bit __test_and_clear_bit_le
936 #define ext4_clear_bit_atomic ext2_clear_bit_atomic
937 #define ext4_test_bit test_bit_le
938 #define ext4_find_first_zero_bit find_first_zero_bit_le
939 #define ext4_find_next_zero_bit find_next_zero_bit_le
940 #define ext4_find_next_bit find_next_bit_le
941
942 /*
943 * Maximal mount counts between two filesystem checks
944 */
945 #define EXT4_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
946 #define EXT4_DFL_CHECKINTERVAL 0 /* Don't use interval check */
947
948 /*
949 * Behaviour when detecting errors
950 */
951 #define EXT4_ERRORS_CONTINUE 1 /* Continue execution */
952 #define EXT4_ERRORS_RO 2 /* Remount fs read-only */
953 #define EXT4_ERRORS_PANIC 3 /* Panic */
954 #define EXT4_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE
955
956 /*
957 * Structure of the super block
958 */
959 struct ext4_super_block {
960 /*00*/ __le32 s_inodes_count; /* Inodes count */
961 __le32 s_blocks_count_lo; /* Blocks count */
962 __le32 s_r_blocks_count_lo; /* Reserved blocks count */
963 __le32 s_free_blocks_count_lo; /* Free blocks count */
964 /*10*/ __le32 s_free_inodes_count; /* Free inodes count */
965 __le32 s_first_data_block; /* First Data Block */
966 __le32 s_log_block_size; /* Block size */
967 __le32 s_obso_log_frag_size; /* Obsoleted fragment size */
968 /*20*/ __le32 s_blocks_per_group; /* # Blocks per group */
969 __le32 s_obso_frags_per_group; /* Obsoleted fragments per group */
970 __le32 s_inodes_per_group; /* # Inodes per group */
971 __le32 s_mtime; /* Mount time */
972 /*30*/ __le32 s_wtime; /* Write time */
973 __le16 s_mnt_count; /* Mount count */
974 __le16 s_max_mnt_count; /* Maximal mount count */
975 __le16 s_magic; /* Magic signature */
976 __le16 s_state; /* File system state */
977 __le16 s_errors; /* Behaviour when detecting errors */
978 __le16 s_minor_rev_level; /* minor revision level */
979 /*40*/ __le32 s_lastcheck; /* time of last check */
980 __le32 s_checkinterval; /* max. time between checks */
981 __le32 s_creator_os; /* OS */
982 __le32 s_rev_level; /* Revision level */
983 /*50*/ __le16 s_def_resuid; /* Default uid for reserved blocks */
984 __le16 s_def_resgid; /* Default gid for reserved blocks */
985 /*
986 * These fields are for EXT4_DYNAMIC_REV superblocks only.
987 *
988 * Note: the difference between the compatible feature set and
989 * the incompatible feature set is that if there is a bit set
990 * in the incompatible feature set that the kernel doesn't
991 * know about, it should refuse to mount the filesystem.
992 *
993 * e2fsck's requirements are more strict; if it doesn't know
994 * about a feature in either the compatible or incompatible
995 * feature set, it must abort and not try to meddle with
996 * things it doesn't understand...
997 */
998 __le32 s_first_ino; /* First non-reserved inode */
999 __le16 s_inode_size; /* size of inode structure */
1000 __le16 s_block_group_nr; /* block group # of this superblock */
1001 __le32 s_feature_compat; /* compatible feature set */
1002 /*60*/ __le32 s_feature_incompat; /* incompatible feature set */
1003 __le32 s_feature_ro_compat; /* readonly-compatible feature set */
1004 /*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */
1005 /*78*/ char s_volume_name[16]; /* volume name */
1006 /*88*/ char s_last_mounted[64]; /* directory where last mounted */
1007 /*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */
1008 /*
1009 * Performance hints. Directory preallocation should only
1010 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1011 */
1012 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
1013 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
1014 __le16 s_reserved_gdt_blocks; /* Per group desc for online growth */
1015 /*
1016 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1017 */
1018 /*D0*/ __u8 s_journal_uuid[16]; /* uuid of journal superblock */
1019 /*E0*/ __le32 s_journal_inum; /* inode number of journal file */
1020 __le32 s_journal_dev; /* device number of journal file */
1021 __le32 s_last_orphan; /* start of list of inodes to delete */
1022 __le32 s_hash_seed[4]; /* HTREE hash seed */
1023 __u8 s_def_hash_version; /* Default hash version to use */
1024 __u8 s_jnl_backup_type;
1025 __le16 s_desc_size; /* size of group descriptor */
1026 /*100*/ __le32 s_default_mount_opts;
1027 __le32 s_first_meta_bg; /* First metablock block group */
1028 __le32 s_mkfs_time; /* When the filesystem was created */
1029 __le32 s_jnl_blocks[17]; /* Backup of the journal inode */
1030 /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1031 /*150*/ __le32 s_blocks_count_hi; /* Blocks count */
1032 __le32 s_r_blocks_count_hi; /* Reserved blocks count */
1033 __le32 s_free_blocks_count_hi; /* Free blocks count */
1034 __le16 s_min_extra_isize; /* All inodes have at least # bytes */
1035 __le16 s_want_extra_isize; /* New inodes should reserve # bytes */
1036 __le32 s_flags; /* Miscellaneous flags */
1037 __le16 s_raid_stride; /* RAID stride */
1038 __le16 s_mmp_update_interval; /* # seconds to wait in MMP checking */
1039 __le64 s_mmp_block; /* Block for multi-mount protection */
1040 __le32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
1041 __u8 s_log_groups_per_flex; /* FLEX_BG group size */
1042 __u8 s_reserved_char_pad;
1043 __le16 s_reserved_pad;
1044 __le64 s_kbytes_written; /* nr of lifetime kilobytes written */
1045 __le32 s_snapshot_inum; /* Inode number of active snapshot */
1046 __le32 s_snapshot_id; /* sequential ID of active snapshot */
1047 __le64 s_snapshot_r_blocks_count; /* reserved blocks for active
1048 snapshot's future use */
1049 __le32 s_snapshot_list; /* inode number of the head of the
1050 on-disk snapshot list */
1051 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1052 __le32 s_error_count; /* number of fs errors */
1053 __le32 s_first_error_time; /* first time an error happened */
1054 __le32 s_first_error_ino; /* inode involved in first error */
1055 __le64 s_first_error_block; /* block involved of first error */
1056 __u8 s_first_error_func[32]; /* function where the error happened */
1057 __le32 s_first_error_line; /* line number where error happened */
1058 __le32 s_last_error_time; /* most recent time of an error */
1059 __le32 s_last_error_ino; /* inode involved in last error */
1060 __le32 s_last_error_line; /* line number where error happened */
1061 __le64 s_last_error_block; /* block involved of last error */
1062 __u8 s_last_error_func[32]; /* function where the error happened */
1063 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1064 __u8 s_mount_opts[64];
1065 __le32 s_reserved[112]; /* Padding to the end of the block */
1066 };
1067
1068 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1069
1070 #ifdef __KERNEL__
1071
1072 /*
1073 * run-time mount flags
1074 */
1075 #define EXT4_MF_MNTDIR_SAMPLED 0x0001
1076 #define EXT4_MF_FS_ABORTED 0x0002 /* Fatal error detected */
1077
1078 /*
1079 * fourth extended-fs super-block data in memory
1080 */
1081 struct ext4_sb_info {
1082 unsigned long s_desc_size; /* Size of a group descriptor in bytes */
1083 unsigned long s_inodes_per_block;/* Number of inodes per block */
1084 unsigned long s_blocks_per_group;/* Number of blocks in a group */
1085 unsigned long s_inodes_per_group;/* Number of inodes in a group */
1086 unsigned long s_itb_per_group; /* Number of inode table blocks per group */
1087 unsigned long s_gdb_count; /* Number of group descriptor blocks */
1088 unsigned long s_desc_per_block; /* Number of group descriptors per block */
1089 ext4_group_t s_groups_count; /* Number of groups in the fs */
1090 ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1091 unsigned long s_overhead_last; /* Last calculated overhead */
1092 unsigned long s_blocks_last; /* Last seen block count */
1093 loff_t s_bitmap_maxbytes; /* max bytes for bitmap files */
1094 struct buffer_head * s_sbh; /* Buffer containing the super block */
1095 struct ext4_super_block *s_es; /* Pointer to the super block in the buffer */
1096 struct buffer_head **s_group_desc;
1097 unsigned int s_mount_opt;
1098 unsigned int s_mount_opt2;
1099 unsigned int s_mount_flags;
1100 ext4_fsblk_t s_sb_block;
1101 uid_t s_resuid;
1102 gid_t s_resgid;
1103 unsigned short s_mount_state;
1104 unsigned short s_pad;
1105 int s_addr_per_block_bits;
1106 int s_desc_per_block_bits;
1107 int s_inode_size;
1108 int s_first_ino;
1109 unsigned int s_inode_readahead_blks;
1110 unsigned int s_inode_goal;
1111 spinlock_t s_next_gen_lock;
1112 u32 s_next_generation;
1113 u32 s_hash_seed[4];
1114 int s_def_hash_version;
1115 int s_hash_unsigned; /* 3 if hash should be signed, 0 if not */
1116 struct percpu_counter s_freeblocks_counter;
1117 struct percpu_counter s_freeinodes_counter;
1118 struct percpu_counter s_dirs_counter;
1119 struct percpu_counter s_dirtyblocks_counter;
1120 struct blockgroup_lock *s_blockgroup_lock;
1121 struct proc_dir_entry *s_proc;
1122 struct kobject s_kobj;
1123 struct completion s_kobj_unregister;
1124
1125 /* Journaling */
1126 struct journal_s *s_journal;
1127 struct list_head s_orphan;
1128 struct mutex s_orphan_lock;
1129 struct mutex s_resize_lock;
1130 unsigned long s_commit_interval;
1131 u32 s_max_batch_time;
1132 u32 s_min_batch_time;
1133 struct block_device *journal_bdev;
1134 #ifdef CONFIG_JBD2_DEBUG
1135 struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */
1136 wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */
1137 #endif
1138 #ifdef CONFIG_QUOTA
1139 char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
1140 int s_jquota_fmt; /* Format of quota to use */
1141 #endif
1142 unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1143 struct rb_root system_blks;
1144
1145 #ifdef EXTENTS_STATS
1146 /* ext4 extents stats */
1147 unsigned long s_ext_min;
1148 unsigned long s_ext_max;
1149 unsigned long s_depth_max;
1150 spinlock_t s_ext_stats_lock;
1151 unsigned long s_ext_blocks;
1152 unsigned long s_ext_extents;
1153 #endif
1154 /* ext4 extent cache stats */
1155 unsigned long extent_cache_hits;
1156 unsigned long extent_cache_misses;
1157
1158 /* for buddy allocator */
1159 struct ext4_group_info ***s_group_info;
1160 struct inode *s_buddy_cache;
1161 spinlock_t s_md_lock;
1162 unsigned short *s_mb_offsets;
1163 unsigned int *s_mb_maxs;
1164
1165 /* tunables */
1166 unsigned long s_stripe;
1167 unsigned int s_mb_stream_request;
1168 unsigned int s_mb_max_to_scan;
1169 unsigned int s_mb_min_to_scan;
1170 unsigned int s_mb_stats;
1171 unsigned int s_mb_order2_reqs;
1172 unsigned int s_mb_group_prealloc;
1173 unsigned int s_max_writeback_mb_bump;
1174 /* where last allocation was done - for stream allocation */
1175 unsigned long s_mb_last_group;
1176 unsigned long s_mb_last_start;
1177
1178 /* stats for buddy allocator */
1179 atomic_t s_bal_reqs; /* number of reqs with len > 1 */
1180 atomic_t s_bal_success; /* we found long enough chunks */
1181 atomic_t s_bal_allocated; /* in blocks */
1182 atomic_t s_bal_ex_scanned; /* total extents scanned */
1183 atomic_t s_bal_goals; /* goal hits */
1184 atomic_t s_bal_breaks; /* too long searches */
1185 atomic_t s_bal_2orders; /* 2^order hits */
1186 spinlock_t s_bal_lock;
1187 unsigned long s_mb_buddies_generated;
1188 unsigned long long s_mb_generation_time;
1189 atomic_t s_mb_lost_chunks;
1190 atomic_t s_mb_preallocated;
1191 atomic_t s_mb_discarded;
1192 atomic_t s_lock_busy;
1193
1194 /* locality groups */
1195 struct ext4_locality_group __percpu *s_locality_groups;
1196
1197 /* for write statistics */
1198 unsigned long s_sectors_written_start;
1199 u64 s_kbytes_written;
1200
1201 unsigned int s_log_groups_per_flex;
1202 struct flex_groups *s_flex_groups;
1203
1204 /* workqueue for dio unwritten */
1205 struct workqueue_struct *dio_unwritten_wq;
1206
1207 /* timer for periodic error stats printing */
1208 struct timer_list s_err_report;
1209
1210 /* Lazy inode table initialization info */
1211 struct ext4_li_request *s_li_request;
1212 /* Wait multiplier for lazy initialization thread */
1213 unsigned int s_li_wait_mult;
1214
1215 /* Kernel thread for multiple mount protection */
1216 struct task_struct *s_mmp_tsk;
1217 };
1218
1219 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1220 {
1221 return sb->s_fs_info;
1222 }
1223 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1224 {
1225 return container_of(inode, struct ext4_inode_info, vfs_inode);
1226 }
1227
1228 static inline struct timespec ext4_current_time(struct inode *inode)
1229 {
1230 return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1231 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1232 }
1233
1234 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1235 {
1236 return ino == EXT4_ROOT_INO ||
1237 ino == EXT4_JOURNAL_INO ||
1238 ino == EXT4_RESIZE_INO ||
1239 (ino >= EXT4_FIRST_INO(sb) &&
1240 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1241 }
1242
1243 /*
1244 * Inode dynamic state flags
1245 */
1246 enum {
1247 EXT4_STATE_JDATA, /* journaled data exists */
1248 EXT4_STATE_NEW, /* inode is newly created */
1249 EXT4_STATE_XATTR, /* has in-inode xattrs */
1250 EXT4_STATE_NO_EXPAND, /* No space for expansion */
1251 EXT4_STATE_DA_ALLOC_CLOSE, /* Alloc DA blks on close */
1252 EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */
1253 EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/
1254 EXT4_STATE_NEWENTRY, /* File just added to dir */
1255 EXT4_STATE_DELALLOC_RESERVED, /* blks already reserved for delalloc */
1256 };
1257
1258 #define EXT4_INODE_BIT_FNS(name, field, offset) \
1259 static inline int ext4_test_inode_##name(struct inode *inode, int bit) \
1260 { \
1261 return test_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1262 } \
1263 static inline void ext4_set_inode_##name(struct inode *inode, int bit) \
1264 { \
1265 set_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1266 } \
1267 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1268 { \
1269 clear_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1270 }
1271
1272 EXT4_INODE_BIT_FNS(flag, flags, 0)
1273 #if (BITS_PER_LONG < 64)
1274 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1275
1276 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1277 {
1278 (ei)->i_state_flags = 0;
1279 }
1280 #else
1281 EXT4_INODE_BIT_FNS(state, flags, 32)
1282
1283 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1284 {
1285 /* We depend on the fact that callers will set i_flags */
1286 }
1287 #endif
1288 #else
1289 /* Assume that user mode programs are passing in an ext4fs superblock, not
1290 * a kernel struct super_block. This will allow us to call the feature-test
1291 * macros from user land. */
1292 #define EXT4_SB(sb) (sb)
1293 #endif
1294
1295 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1296
1297 /*
1298 * Codes for operating systems
1299 */
1300 #define EXT4_OS_LINUX 0
1301 #define EXT4_OS_HURD 1
1302 #define EXT4_OS_MASIX 2
1303 #define EXT4_OS_FREEBSD 3
1304 #define EXT4_OS_LITES 4
1305
1306 /*
1307 * Revision levels
1308 */
1309 #define EXT4_GOOD_OLD_REV 0 /* The good old (original) format */
1310 #define EXT4_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
1311
1312 #define EXT4_CURRENT_REV EXT4_GOOD_OLD_REV
1313 #define EXT4_MAX_SUPP_REV EXT4_DYNAMIC_REV
1314
1315 #define EXT4_GOOD_OLD_INODE_SIZE 128
1316
1317 /*
1318 * Feature set definitions
1319 */
1320
1321 #define EXT4_HAS_COMPAT_FEATURE(sb,mask) \
1322 ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1323 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask) \
1324 ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1325 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask) \
1326 ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1327 #define EXT4_SET_COMPAT_FEATURE(sb,mask) \
1328 EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1329 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask) \
1330 EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1331 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask) \
1332 EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1333 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask) \
1334 EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1335 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
1336 EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1337 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask) \
1338 EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1339
1340 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001
1341 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002
1342 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004
1343 #define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008
1344 #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010
1345 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020
1346
1347 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
1348 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
1349 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
1350 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
1351 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
1352 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
1353 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
1354 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
1355
1356 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
1357 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
1358 #define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
1359 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
1360 #define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
1361 #define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
1362 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
1363 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
1364 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
1365 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */
1366 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */
1367
1368 #define EXT2_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
1369 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1370 EXT4_FEATURE_INCOMPAT_META_BG)
1371 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1372 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1373 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1374
1375 #define EXT3_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
1376 #define EXT3_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1377 EXT4_FEATURE_INCOMPAT_RECOVER| \
1378 EXT4_FEATURE_INCOMPAT_META_BG)
1379 #define EXT3_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1380 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1381 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1382
1383 #define EXT4_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
1384 #define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1385 EXT4_FEATURE_INCOMPAT_RECOVER| \
1386 EXT4_FEATURE_INCOMPAT_META_BG| \
1387 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1388 EXT4_FEATURE_INCOMPAT_64BIT| \
1389 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1390 EXT4_FEATURE_INCOMPAT_MMP)
1391 #define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1392 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1393 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1394 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1395 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1396 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1397 EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1398
1399 /*
1400 * Default values for user and/or group using reserved blocks
1401 */
1402 #define EXT4_DEF_RESUID 0
1403 #define EXT4_DEF_RESGID 0
1404
1405 #define EXT4_DEF_INODE_READAHEAD_BLKS 32
1406
1407 /*
1408 * Default mount options
1409 */
1410 #define EXT4_DEFM_DEBUG 0x0001
1411 #define EXT4_DEFM_BSDGROUPS 0x0002
1412 #define EXT4_DEFM_XATTR_USER 0x0004
1413 #define EXT4_DEFM_ACL 0x0008
1414 #define EXT4_DEFM_UID16 0x0010
1415 #define EXT4_DEFM_JMODE 0x0060
1416 #define EXT4_DEFM_JMODE_DATA 0x0020
1417 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1418 #define EXT4_DEFM_JMODE_WBACK 0x0060
1419 #define EXT4_DEFM_NOBARRIER 0x0100
1420 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1421 #define EXT4_DEFM_DISCARD 0x0400
1422 #define EXT4_DEFM_NODELALLOC 0x0800
1423
1424 /*
1425 * Default journal batch times
1426 */
1427 #define EXT4_DEF_MIN_BATCH_TIME 0
1428 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1429
1430 /*
1431 * Minimum number of groups in a flexgroup before we separate out
1432 * directories into the first block group of a flexgroup
1433 */
1434 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1435
1436 /*
1437 * Structure of a directory entry
1438 */
1439 #define EXT4_NAME_LEN 255
1440
1441 struct ext4_dir_entry {
1442 __le32 inode; /* Inode number */
1443 __le16 rec_len; /* Directory entry length */
1444 __le16 name_len; /* Name length */
1445 char name[EXT4_NAME_LEN]; /* File name */
1446 };
1447
1448 /*
1449 * The new version of the directory entry. Since EXT4 structures are
1450 * stored in intel byte order, and the name_len field could never be
1451 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1452 * file_type field.
1453 */
1454 struct ext4_dir_entry_2 {
1455 __le32 inode; /* Inode number */
1456 __le16 rec_len; /* Directory entry length */
1457 __u8 name_len; /* Name length */
1458 __u8 file_type;
1459 char name[EXT4_NAME_LEN]; /* File name */
1460 };
1461
1462 /*
1463 * Ext4 directory file types. Only the low 3 bits are used. The
1464 * other bits are reserved for now.
1465 */
1466 #define EXT4_FT_UNKNOWN 0
1467 #define EXT4_FT_REG_FILE 1
1468 #define EXT4_FT_DIR 2
1469 #define EXT4_FT_CHRDEV 3
1470 #define EXT4_FT_BLKDEV 4
1471 #define EXT4_FT_FIFO 5
1472 #define EXT4_FT_SOCK 6
1473 #define EXT4_FT_SYMLINK 7
1474
1475 #define EXT4_FT_MAX 8
1476
1477 /*
1478 * EXT4_DIR_PAD defines the directory entries boundaries
1479 *
1480 * NOTE: It must be a multiple of 4
1481 */
1482 #define EXT4_DIR_PAD 4
1483 #define EXT4_DIR_ROUND (EXT4_DIR_PAD - 1)
1484 #define EXT4_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT4_DIR_ROUND) & \
1485 ~EXT4_DIR_ROUND)
1486 #define EXT4_MAX_REC_LEN ((1<<16)-1)
1487
1488 /*
1489 * If we ever get support for fs block sizes > page_size, we'll need
1490 * to remove the #if statements in the next two functions...
1491 */
1492 static inline unsigned int
1493 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1494 {
1495 unsigned len = le16_to_cpu(dlen);
1496
1497 #if (PAGE_CACHE_SIZE >= 65536)
1498 if (len == EXT4_MAX_REC_LEN || len == 0)
1499 return blocksize;
1500 return (len & 65532) | ((len & 3) << 16);
1501 #else
1502 return len;
1503 #endif
1504 }
1505
1506 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1507 {
1508 if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1509 BUG();
1510 #if (PAGE_CACHE_SIZE >= 65536)
1511 if (len < 65536)
1512 return cpu_to_le16(len);
1513 if (len == blocksize) {
1514 if (blocksize == 65536)
1515 return cpu_to_le16(EXT4_MAX_REC_LEN);
1516 else
1517 return cpu_to_le16(0);
1518 }
1519 return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1520 #else
1521 return cpu_to_le16(len);
1522 #endif
1523 }
1524
1525 /*
1526 * Hash Tree Directory indexing
1527 * (c) Daniel Phillips, 2001
1528 */
1529
1530 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1531 EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1532 ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1533 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1534 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1535
1536 /* Legal values for the dx_root hash_version field: */
1537
1538 #define DX_HASH_LEGACY 0
1539 #define DX_HASH_HALF_MD4 1
1540 #define DX_HASH_TEA 2
1541 #define DX_HASH_LEGACY_UNSIGNED 3
1542 #define DX_HASH_HALF_MD4_UNSIGNED 4
1543 #define DX_HASH_TEA_UNSIGNED 5
1544
1545 #ifdef __KERNEL__
1546
1547 /* hash info structure used by the directory hash */
1548 struct dx_hash_info
1549 {
1550 u32 hash;
1551 u32 minor_hash;
1552 int hash_version;
1553 u32 *seed;
1554 };
1555
1556 #define EXT4_HTREE_EOF 0x7fffffff
1557
1558 /*
1559 * Control parameters used by ext4_htree_next_block
1560 */
1561 #define HASH_NB_ALWAYS 1
1562
1563
1564 /*
1565 * Describe an inode's exact location on disk and in memory
1566 */
1567 struct ext4_iloc
1568 {
1569 struct buffer_head *bh;
1570 unsigned long offset;
1571 ext4_group_t block_group;
1572 };
1573
1574 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1575 {
1576 return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1577 }
1578
1579 /*
1580 * This structure is stuffed into the struct file's private_data field
1581 * for directories. It is where we put information so that we can do
1582 * readdir operations in hash tree order.
1583 */
1584 struct dir_private_info {
1585 struct rb_root root;
1586 struct rb_node *curr_node;
1587 struct fname *extra_fname;
1588 loff_t last_pos;
1589 __u32 curr_hash;
1590 __u32 curr_minor_hash;
1591 __u32 next_hash;
1592 };
1593
1594 /* calculate the first block number of the group */
1595 static inline ext4_fsblk_t
1596 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1597 {
1598 return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1599 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1600 }
1601
1602 /*
1603 * Special error return code only used by dx_probe() and its callers.
1604 */
1605 #define ERR_BAD_DX_DIR -75000
1606
1607 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1608 ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1609
1610 /*
1611 * Timeout and state flag for lazy initialization inode thread.
1612 */
1613 #define EXT4_DEF_LI_WAIT_MULT 10
1614 #define EXT4_DEF_LI_MAX_START_DELAY 5
1615 #define EXT4_LAZYINIT_QUIT 0x0001
1616 #define EXT4_LAZYINIT_RUNNING 0x0002
1617
1618 /*
1619 * Lazy inode table initialization info
1620 */
1621 struct ext4_lazy_init {
1622 unsigned long li_state;
1623 struct list_head li_request_list;
1624 struct mutex li_list_mtx;
1625 };
1626
1627 struct ext4_li_request {
1628 struct super_block *lr_super;
1629 struct ext4_sb_info *lr_sbi;
1630 ext4_group_t lr_next_group;
1631 struct list_head lr_request;
1632 unsigned long lr_next_sched;
1633 unsigned long lr_timeout;
1634 };
1635
1636 struct ext4_features {
1637 struct kobject f_kobj;
1638 struct completion f_kobj_unregister;
1639 };
1640
1641 /*
1642 * This structure will be used for multiple mount protection. It will be
1643 * written into the block number saved in the s_mmp_block field in the
1644 * superblock. Programs that check MMP should assume that if
1645 * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1646 * to use the filesystem, regardless of how old the timestamp is.
1647 */
1648 #define EXT4_MMP_MAGIC 0x004D4D50U /* ASCII for MMP */
1649 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1650 #define EXT4_MMP_SEQ_FSCK 0xE24D4D50U /* mmp_seq value when being fscked */
1651 #define EXT4_MMP_SEQ_MAX 0xE24D4D4FU /* maximum valid mmp_seq value */
1652
1653 struct mmp_struct {
1654 __le32 mmp_magic; /* Magic number for MMP */
1655 __le32 mmp_seq; /* Sequence no. updated periodically */
1656
1657 /*
1658 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1659 * purposes and do not affect the correctness of the algorithm
1660 */
1661 __le64 mmp_time; /* Time last updated */
1662 char mmp_nodename[64]; /* Node which last updated MMP block */
1663 char mmp_bdevname[32]; /* Bdev which last updated MMP block */
1664
1665 /*
1666 * mmp_check_interval is used to verify if the MMP block has been
1667 * updated on the block device. The value is updated based on the
1668 * maximum time to write the MMP block during an update cycle.
1669 */
1670 __le16 mmp_check_interval;
1671
1672 __le16 mmp_pad1;
1673 __le32 mmp_pad2[227];
1674 };
1675
1676 /* arguments passed to the mmp thread */
1677 struct mmpd_data {
1678 struct buffer_head *bh; /* bh from initial read_mmp_block() */
1679 struct super_block *sb; /* super block of the fs */
1680 };
1681
1682 /*
1683 * Check interval multiplier
1684 * The MMP block is written every update interval and initially checked every
1685 * update interval x the multiplier (the value is then adapted based on the
1686 * write latency). The reason is that writes can be delayed under load and we
1687 * don't want readers to incorrectly assume that the filesystem is no longer
1688 * in use.
1689 */
1690 #define EXT4_MMP_CHECK_MULT 2UL
1691
1692 /*
1693 * Minimum interval for MMP checking in seconds.
1694 */
1695 #define EXT4_MMP_MIN_CHECK_INTERVAL 5UL
1696
1697 /*
1698 * Maximum interval for MMP checking in seconds.
1699 */
1700 #define EXT4_MMP_MAX_CHECK_INTERVAL 300UL
1701
1702 /*
1703 * Function prototypes
1704 */
1705
1706 /*
1707 * Ok, these declarations are also in <linux/kernel.h> but none of the
1708 * ext4 source programs needs to include it so they are duplicated here.
1709 */
1710 # define NORET_TYPE /**/
1711 # define ATTRIB_NORET __attribute__((noreturn))
1712 # define NORET_AND noreturn,
1713
1714 /* bitmap.c */
1715 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1716
1717 /* balloc.c */
1718 extern unsigned int ext4_block_group(struct super_block *sb,
1719 ext4_fsblk_t blocknr);
1720 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1721 ext4_fsblk_t blocknr);
1722 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1723 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1724 ext4_group_t group);
1725 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1726 ext4_fsblk_t goal,
1727 unsigned int flags,
1728 unsigned long *count,
1729 int *errp);
1730 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
1731 s64 nblocks, unsigned int flags);
1732 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1733 extern void ext4_check_blocks_bitmap(struct super_block *);
1734 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1735 ext4_group_t block_group,
1736 struct buffer_head ** bh);
1737 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1738 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1739 ext4_group_t block_group);
1740 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1741 struct buffer_head *bh,
1742 ext4_group_t group,
1743 struct ext4_group_desc *desc);
1744 #define ext4_free_blocks_after_init(sb, group, desc) \
1745 ext4_init_block_bitmap(sb, NULL, group, desc)
1746
1747 /* dir.c */
1748 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1749 struct file *,
1750 struct ext4_dir_entry_2 *,
1751 struct buffer_head *, unsigned int);
1752 #define ext4_check_dir_entry(dir, filp, de, bh, offset) \
1753 unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1754 (de), (bh), (offset)))
1755 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1756 __u32 minor_hash,
1757 struct ext4_dir_entry_2 *dirent);
1758 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1759
1760 /* fsync.c */
1761 extern int ext4_sync_file(struct file *, int);
1762 extern int ext4_flush_completed_IO(struct inode *);
1763
1764 /* hash.c */
1765 extern int ext4fs_dirhash(const char *name, int len, struct
1766 dx_hash_info *hinfo);
1767
1768 /* ialloc.c */
1769 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1770 const struct qstr *qstr, __u32 goal);
1771 extern void ext4_free_inode(handle_t *, struct inode *);
1772 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1773 extern unsigned long ext4_count_free_inodes(struct super_block *);
1774 extern unsigned long ext4_count_dirs(struct super_block *);
1775 extern void ext4_check_inodes_bitmap(struct super_block *);
1776 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1777 extern int ext4_init_inode_table(struct super_block *sb,
1778 ext4_group_t group, int barrier);
1779
1780 /* mballoc.c */
1781 extern long ext4_mb_stats;
1782 extern long ext4_mb_max_to_scan;
1783 extern int ext4_mb_init(struct super_block *, int);
1784 extern int ext4_mb_release(struct super_block *);
1785 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1786 struct ext4_allocation_request *, int *);
1787 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1788 extern void ext4_discard_preallocations(struct inode *);
1789 extern int __init ext4_init_mballoc(void);
1790 extern void ext4_exit_mballoc(void);
1791 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1792 struct buffer_head *bh, ext4_fsblk_t block,
1793 unsigned long count, int flags);
1794 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1795 ext4_group_t i, struct ext4_group_desc *desc);
1796 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1797 ext4_fsblk_t block, unsigned long count);
1798 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1799
1800 /* inode.c */
1801 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1802 ext4_lblk_t, int, int *);
1803 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1804 ext4_lblk_t, int, int *);
1805 int ext4_get_block(struct inode *inode, sector_t iblock,
1806 struct buffer_head *bh_result, int create);
1807
1808 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1809 extern int ext4_write_inode(struct inode *, struct writeback_control *);
1810 extern int ext4_setattr(struct dentry *, struct iattr *);
1811 extern int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1812 struct kstat *stat);
1813 extern void ext4_evict_inode(struct inode *);
1814 extern void ext4_clear_inode(struct inode *);
1815 extern int ext4_sync_inode(handle_t *, struct inode *);
1816 extern void ext4_dirty_inode(struct inode *, int);
1817 extern int ext4_change_inode_journal_flag(struct inode *, int);
1818 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1819 extern int ext4_can_truncate(struct inode *inode);
1820 extern void ext4_truncate(struct inode *);
1821 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1822 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1823 extern void ext4_set_inode_flags(struct inode *);
1824 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1825 extern int ext4_alloc_da_blocks(struct inode *inode);
1826 extern void ext4_set_aops(struct inode *inode);
1827 extern int ext4_writepage_trans_blocks(struct inode *);
1828 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1829 extern int ext4_block_truncate_page(handle_t *handle,
1830 struct address_space *mapping, loff_t from);
1831 extern int ext4_block_zero_page_range(handle_t *handle,
1832 struct address_space *mapping, loff_t from, loff_t length);
1833 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1834 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1835 extern void ext4_da_update_reserve_space(struct inode *inode,
1836 int used, int quota_claim);
1837 /* ioctl.c */
1838 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1839 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1840
1841 /* migrate.c */
1842 extern int ext4_ext_migrate(struct inode *);
1843
1844 /* namei.c */
1845 extern int ext4_orphan_add(handle_t *, struct inode *);
1846 extern int ext4_orphan_del(handle_t *, struct inode *);
1847 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1848 __u32 start_minor_hash, __u32 *next_hash);
1849
1850 /* resize.c */
1851 extern int ext4_group_add(struct super_block *sb,
1852 struct ext4_new_group_data *input);
1853 extern int ext4_group_extend(struct super_block *sb,
1854 struct ext4_super_block *es,
1855 ext4_fsblk_t n_blocks_count);
1856
1857 /* super.c */
1858 extern void __ext4_error(struct super_block *, const char *, unsigned int,
1859 const char *, ...)
1860 __attribute__ ((format (printf, 4, 5)));
1861 #define ext4_error(sb, message...) __ext4_error(sb, __func__, \
1862 __LINE__, ## message)
1863 extern void ext4_error_inode(struct inode *, const char *, unsigned int,
1864 ext4_fsblk_t, const char *, ...)
1865 __attribute__ ((format (printf, 5, 6)));
1866 extern void ext4_error_file(struct file *, const char *, unsigned int,
1867 ext4_fsblk_t, const char *, ...)
1868 __attribute__ ((format (printf, 5, 6)));
1869 extern void __ext4_std_error(struct super_block *, const char *,
1870 unsigned int, int);
1871 extern void __ext4_abort(struct super_block *, const char *, unsigned int,
1872 const char *, ...)
1873 __attribute__ ((format (printf, 4, 5)));
1874 #define ext4_abort(sb, message...) __ext4_abort(sb, __func__, \
1875 __LINE__, ## message)
1876 extern void __ext4_warning(struct super_block *, const char *, unsigned int,
1877 const char *, ...)
1878 __attribute__ ((format (printf, 4, 5)));
1879 #define ext4_warning(sb, message...) __ext4_warning(sb, __func__, \
1880 __LINE__, ## message)
1881 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1882 __attribute__ ((format (printf, 3, 4)));
1883 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
1884 const char *, unsigned int, const char *);
1885 #define dump_mmp_msg(sb, mmp, msg) __dump_mmp_msg(sb, mmp, __func__, \
1886 __LINE__, msg)
1887 extern void __ext4_grp_locked_error(const char *, unsigned int, \
1888 struct super_block *, ext4_group_t, \
1889 unsigned long, ext4_fsblk_t, \
1890 const char *, ...)
1891 __attribute__ ((format (printf, 7, 8)));
1892 #define ext4_grp_locked_error(sb, grp, message...) \
1893 __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1894 extern void ext4_update_dynamic_rev(struct super_block *sb);
1895 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1896 __u32 compat);
1897 extern int ext4_update_rocompat_feature(handle_t *handle,
1898 struct super_block *sb, __u32 rocompat);
1899 extern int ext4_update_incompat_feature(handle_t *handle,
1900 struct super_block *sb, __u32 incompat);
1901 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1902 struct ext4_group_desc *bg);
1903 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1904 struct ext4_group_desc *bg);
1905 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1906 struct ext4_group_desc *bg);
1907 extern __u32 ext4_free_blks_count(struct super_block *sb,
1908 struct ext4_group_desc *bg);
1909 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1910 struct ext4_group_desc *bg);
1911 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1912 struct ext4_group_desc *bg);
1913 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1914 struct ext4_group_desc *bg);
1915 extern void ext4_block_bitmap_set(struct super_block *sb,
1916 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1917 extern void ext4_inode_bitmap_set(struct super_block *sb,
1918 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1919 extern void ext4_inode_table_set(struct super_block *sb,
1920 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1921 extern void ext4_free_blks_set(struct super_block *sb,
1922 struct ext4_group_desc *bg, __u32 count);
1923 extern void ext4_free_inodes_set(struct super_block *sb,
1924 struct ext4_group_desc *bg, __u32 count);
1925 extern void ext4_used_dirs_set(struct super_block *sb,
1926 struct ext4_group_desc *bg, __u32 count);
1927 extern void ext4_itable_unused_set(struct super_block *sb,
1928 struct ext4_group_desc *bg, __u32 count);
1929 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1930 struct ext4_group_desc *gdp);
1931 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1932 struct ext4_group_desc *gdp);
1933
1934 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1935 {
1936 return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1937 le32_to_cpu(es->s_blocks_count_lo);
1938 }
1939
1940 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1941 {
1942 return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1943 le32_to_cpu(es->s_r_blocks_count_lo);
1944 }
1945
1946 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1947 {
1948 return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1949 le32_to_cpu(es->s_free_blocks_count_lo);
1950 }
1951
1952 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1953 ext4_fsblk_t blk)
1954 {
1955 es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1956 es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1957 }
1958
1959 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1960 ext4_fsblk_t blk)
1961 {
1962 es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1963 es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1964 }
1965
1966 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1967 ext4_fsblk_t blk)
1968 {
1969 es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1970 es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1971 }
1972
1973 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1974 {
1975 if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1976 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1977 le32_to_cpu(raw_inode->i_size_lo);
1978 else
1979 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1980 }
1981
1982 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1983 {
1984 raw_inode->i_size_lo = cpu_to_le32(i_size);
1985 raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1986 }
1987
1988 static inline
1989 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1990 ext4_group_t group)
1991 {
1992 struct ext4_group_info ***grp_info;
1993 long indexv, indexh;
1994 grp_info = EXT4_SB(sb)->s_group_info;
1995 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1996 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1997 return grp_info[indexv][indexh];
1998 }
1999
2000 /*
2001 * Reading s_groups_count requires using smp_rmb() afterwards. See
2002 * the locking protocol documented in the comments of ext4_group_add()
2003 * in resize.c
2004 */
2005 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2006 {
2007 ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2008
2009 smp_rmb();
2010 return ngroups;
2011 }
2012
2013 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2014 ext4_group_t block_group)
2015 {
2016 return block_group >> sbi->s_log_groups_per_flex;
2017 }
2018
2019 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2020 {
2021 return 1 << sbi->s_log_groups_per_flex;
2022 }
2023
2024 #define ext4_std_error(sb, errno) \
2025 do { \
2026 if ((errno)) \
2027 __ext4_std_error((sb), __func__, __LINE__, (errno)); \
2028 } while (0)
2029
2030 #ifdef CONFIG_SMP
2031 /* Each CPU can accumulate percpu_counter_batch blocks in their local
2032 * counters. So we need to make sure we have free blocks more
2033 * than percpu_counter_batch * nr_cpu_ids. Also add a window of 4 times.
2034 */
2035 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2036 #else
2037 #define EXT4_FREEBLOCKS_WATERMARK 0
2038 #endif
2039
2040 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2041 {
2042 /*
2043 * XXX: replace with spinlock if seen contended -bzzz
2044 */
2045 down_write(&EXT4_I(inode)->i_data_sem);
2046 if (newsize > EXT4_I(inode)->i_disksize)
2047 EXT4_I(inode)->i_disksize = newsize;
2048 up_write(&EXT4_I(inode)->i_data_sem);
2049 return ;
2050 }
2051
2052 struct ext4_group_info {
2053 unsigned long bb_state;
2054 struct rb_root bb_free_root;
2055 ext4_grpblk_t bb_first_free; /* first free block */
2056 ext4_grpblk_t bb_free; /* total free blocks */
2057 ext4_grpblk_t bb_fragments; /* nr of freespace fragments */
2058 ext4_grpblk_t bb_largest_free_order;/* order of largest frag in BG */
2059 struct list_head bb_prealloc_list;
2060 #ifdef DOUBLE_CHECK
2061 void *bb_bitmap;
2062 #endif
2063 struct rw_semaphore alloc_sem;
2064 ext4_grpblk_t bb_counters[]; /* Nr of free power-of-two-block
2065 * regions, index is order.
2066 * bb_counters[3] = 5 means
2067 * 5 free 8-block regions. */
2068 };
2069
2070 #define EXT4_GROUP_INFO_NEED_INIT_BIT 0
2071
2072 #define EXT4_MB_GRP_NEED_INIT(grp) \
2073 (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2074
2075 #define EXT4_MAX_CONTENTION 8
2076 #define EXT4_CONTENTION_THRESHOLD 2
2077
2078 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2079 ext4_group_t group)
2080 {
2081 return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2082 }
2083
2084 /*
2085 * Returns true if the filesystem is busy enough that attempts to
2086 * access the block group locks has run into contention.
2087 */
2088 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2089 {
2090 return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2091 }
2092
2093 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2094 {
2095 spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2096 if (spin_trylock(lock))
2097 /*
2098 * We're able to grab the lock right away, so drop the
2099 * lock contention counter.
2100 */
2101 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2102 else {
2103 /*
2104 * The lock is busy, so bump the contention counter,
2105 * and then wait on the spin lock.
2106 */
2107 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2108 EXT4_MAX_CONTENTION);
2109 spin_lock(lock);
2110 }
2111 }
2112
2113 static inline void ext4_unlock_group(struct super_block *sb,
2114 ext4_group_t group)
2115 {
2116 spin_unlock(ext4_group_lock_ptr(sb, group));
2117 }
2118
2119 static inline void ext4_mark_super_dirty(struct super_block *sb)
2120 {
2121 if (EXT4_SB(sb)->s_journal == NULL)
2122 sb->s_dirt =1;
2123 }
2124
2125 /*
2126 * Inodes and files operations
2127 */
2128
2129 /* dir.c */
2130 extern const struct file_operations ext4_dir_operations;
2131
2132 /* file.c */
2133 extern const struct inode_operations ext4_file_inode_operations;
2134 extern const struct file_operations ext4_file_operations;
2135 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2136
2137 /* namei.c */
2138 extern const struct inode_operations ext4_dir_inode_operations;
2139 extern const struct inode_operations ext4_special_inode_operations;
2140 extern struct dentry *ext4_get_parent(struct dentry *child);
2141
2142 /* symlink.c */
2143 extern const struct inode_operations ext4_symlink_inode_operations;
2144 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2145
2146 /* block_validity */
2147 extern void ext4_release_system_zone(struct super_block *sb);
2148 extern int ext4_setup_system_zone(struct super_block *sb);
2149 extern int __init ext4_init_system_zone(void);
2150 extern void ext4_exit_system_zone(void);
2151 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2152 ext4_fsblk_t start_blk,
2153 unsigned int count);
2154
2155 /* extents.c */
2156 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2157 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2158 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2159 int chunk);
2160 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2161 struct ext4_map_blocks *map, int flags);
2162 extern void ext4_ext_truncate(struct inode *);
2163 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2164 loff_t length);
2165 extern void ext4_ext_init(struct super_block *);
2166 extern void ext4_ext_release(struct super_block *);
2167 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2168 loff_t len);
2169 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2170 ssize_t len);
2171 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2172 struct ext4_map_blocks *map, int flags);
2173 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2174 __u64 start, __u64 len);
2175 /* move_extent.c */
2176 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2177 __u64 start_orig, __u64 start_donor,
2178 __u64 len, __u64 *moved_len);
2179
2180 /* page-io.c */
2181 extern int __init ext4_init_pageio(void);
2182 extern void ext4_exit_pageio(void);
2183 extern void ext4_ioend_wait(struct inode *);
2184 extern void ext4_free_io_end(ext4_io_end_t *io);
2185 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2186 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2187 extern void ext4_io_submit(struct ext4_io_submit *io);
2188 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2189 struct page *page,
2190 int len,
2191 struct writeback_control *wbc);
2192
2193 /* mmp.c */
2194 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2195
2196 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2197 enum ext4_state_bits {
2198 BH_Uninit /* blocks are allocated but uninitialized on disk */
2199 = BH_JBDPrivateStart,
2200 };
2201
2202 BUFFER_FNS(Uninit, uninit)
2203 TAS_BUFFER_FNS(Uninit, uninit)
2204
2205 /*
2206 * Add new method to test wether block and inode bitmaps are properly
2207 * initialized. With uninit_bg reading the block from disk is not enough
2208 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2209 */
2210 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2211
2212 static inline int bitmap_uptodate(struct buffer_head *bh)
2213 {
2214 return (buffer_uptodate(bh) &&
2215 test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2216 }
2217 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2218 {
2219 set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2220 }
2221
2222 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2223
2224 /* For ioend & aio unwritten conversion wait queues */
2225 #define EXT4_WQ_HASH_SZ 37
2226 #define ext4_ioend_wq(v) (&ext4__ioend_wq[((unsigned long)(v)) %\
2227 EXT4_WQ_HASH_SZ])
2228 #define ext4_aio_mutex(v) (&ext4__aio_mutex[((unsigned long)(v)) %\
2229 EXT4_WQ_HASH_SZ])
2230 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2231 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2232
2233 #endif /* __KERNEL__ */
2234
2235 #endif /* _EXT4_H */
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