ehea: fix skb_frag_size typo
[linux-btrfs-devel.git] / fs / ext4 / ext4.h
blobb7d7bd0f066ef4d02d9cba1cf2f72704cb44a4f5
1 /*
2 * ext4.h
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)
9 * from
11 * linux/include/linux/minix_fs.h
13 * Copyright (C) 1991, 1992 Linus Torvalds
16 #ifndef _EXT4_H
17 #define _EXT4_H
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
37 * The fourth extended filesystem constants/structures
41 * Define EXT4FS_DEBUG to produce debug messages
43 #undef EXT4FS_DEBUG
46 * Debug code
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
59 #define EXT4_ERROR_INODE(inode, fmt, a...) \
60 ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
62 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...) \
63 ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
65 #define EXT4_ERROR_FILE(file, block, fmt, a...) \
66 ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
68 /* data type for block offset of block group */
69 typedef int ext4_grpblk_t;
71 /* data type for filesystem-wide blocks number */
72 typedef unsigned long long ext4_fsblk_t;
74 /* data type for file logical block number */
75 typedef __u32 ext4_lblk_t;
77 /* data type for block group number */
78 typedef unsigned int ext4_group_t;
81 * Flags used in mballoc's allocation_context flags field.
83 * Also used to show what's going on for debugging purposes when the
84 * flag field is exported via the traceport interface
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
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;
136 * Logical to physical block mapping, used by ext4_map_blocks()
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.
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)
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;
159 * For delayed allocation tracking
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;
174 * Flags for ext4_io_end->flags
176 #define EXT4_IO_END_UNWRITTEN 0x0001
177 #define EXT4_IO_END_ERROR 0x0002
178 #define EXT4_IO_END_QUEUED 0x0004
180 struct ext4_io_page {
181 struct page *p_page;
182 atomic_t p_count;
185 #define MAX_IO_PAGES 128
187 typedef struct ext4_io_end {
188 struct list_head list; /* per-file finished IO list */
189 struct inode *inode; /* file being written to */
190 unsigned int flag; /* unwritten or not */
191 struct page *page; /* page struct for buffer write */
192 loff_t offset; /* offset in the file */
193 ssize_t size; /* size of the extent */
194 struct work_struct work; /* data work queue */
195 struct kiocb *iocb; /* iocb struct for AIO */
196 int result; /* error value for AIO */
197 int num_io_pages;
198 struct ext4_io_page *pages[MAX_IO_PAGES];
199 } ext4_io_end_t;
201 struct ext4_io_submit {
202 int io_op;
203 struct bio *io_bio;
204 ext4_io_end_t *io_end;
205 struct ext4_io_page *io_page;
206 sector_t io_next_block;
210 * Special inodes numbers
212 #define EXT4_BAD_INO 1 /* Bad blocks inode */
213 #define EXT4_ROOT_INO 2 /* Root inode */
214 #define EXT4_USR_QUOTA_INO 3 /* User quota inode */
215 #define EXT4_GRP_QUOTA_INO 4 /* Group quota inode */
216 #define EXT4_BOOT_LOADER_INO 5 /* Boot loader inode */
217 #define EXT4_UNDEL_DIR_INO 6 /* Undelete directory inode */
218 #define EXT4_RESIZE_INO 7 /* Reserved group descriptors inode */
219 #define EXT4_JOURNAL_INO 8 /* Journal inode */
221 /* First non-reserved inode for old ext4 filesystems */
222 #define EXT4_GOOD_OLD_FIRST_INO 11
225 * Maximal count of links to a file
227 #define EXT4_LINK_MAX 65000
230 * Macro-instructions used to manage several block sizes
232 #define EXT4_MIN_BLOCK_SIZE 1024
233 #define EXT4_MAX_BLOCK_SIZE 65536
234 #define EXT4_MIN_BLOCK_LOG_SIZE 10
235 #define EXT4_MAX_BLOCK_LOG_SIZE 16
236 #ifdef __KERNEL__
237 # define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize)
238 #else
239 # define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
240 #endif
241 #define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
242 #ifdef __KERNEL__
243 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
244 #else
245 # define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
246 #endif
247 #ifdef __KERNEL__
248 #define EXT4_ADDR_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_addr_per_block_bits)
249 #define EXT4_INODE_SIZE(s) (EXT4_SB(s)->s_inode_size)
250 #define EXT4_FIRST_INO(s) (EXT4_SB(s)->s_first_ino)
251 #else
252 #define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
253 EXT4_GOOD_OLD_INODE_SIZE : \
254 (s)->s_inode_size)
255 #define EXT4_FIRST_INO(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
256 EXT4_GOOD_OLD_FIRST_INO : \
257 (s)->s_first_ino)
258 #endif
259 #define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
262 * Structure of a blocks group descriptor
264 struct ext4_group_desc
266 __le32 bg_block_bitmap_lo; /* Blocks bitmap block */
267 __le32 bg_inode_bitmap_lo; /* Inodes bitmap block */
268 __le32 bg_inode_table_lo; /* Inodes table block */
269 __le16 bg_free_blocks_count_lo;/* Free blocks count */
270 __le16 bg_free_inodes_count_lo;/* Free inodes count */
271 __le16 bg_used_dirs_count_lo; /* Directories count */
272 __le16 bg_flags; /* EXT4_BG_flags (INODE_UNINIT, etc) */
273 __u32 bg_reserved[2]; /* Likely block/inode bitmap checksum */
274 __le16 bg_itable_unused_lo; /* Unused inodes count */
275 __le16 bg_checksum; /* crc16(sb_uuid+group+desc) */
276 __le32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
277 __le32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
278 __le32 bg_inode_table_hi; /* Inodes table block MSB */
279 __le16 bg_free_blocks_count_hi;/* Free blocks count MSB */
280 __le16 bg_free_inodes_count_hi;/* Free inodes count MSB */
281 __le16 bg_used_dirs_count_hi; /* Directories count MSB */
282 __le16 bg_itable_unused_hi; /* Unused inodes count MSB */
283 __u32 bg_reserved2[3];
287 * Structure of a flex block group info
290 struct flex_groups {
291 atomic_t free_inodes;
292 atomic_t free_blocks;
293 atomic_t used_dirs;
296 #define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */
297 #define EXT4_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */
298 #define EXT4_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
301 * Macro-instructions used to manage group descriptors
303 #define EXT4_MIN_DESC_SIZE 32
304 #define EXT4_MIN_DESC_SIZE_64BIT 64
305 #define EXT4_MAX_DESC_SIZE EXT4_MIN_BLOCK_SIZE
306 #define EXT4_DESC_SIZE(s) (EXT4_SB(s)->s_desc_size)
307 #ifdef __KERNEL__
308 # define EXT4_BLOCKS_PER_GROUP(s) (EXT4_SB(s)->s_blocks_per_group)
309 # define EXT4_DESC_PER_BLOCK(s) (EXT4_SB(s)->s_desc_per_block)
310 # define EXT4_INODES_PER_GROUP(s) (EXT4_SB(s)->s_inodes_per_group)
311 # define EXT4_DESC_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_desc_per_block_bits)
312 #else
313 # define EXT4_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
314 # define EXT4_DESC_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
315 # define EXT4_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
316 #endif
319 * Constants relative to the data blocks
321 #define EXT4_NDIR_BLOCKS 12
322 #define EXT4_IND_BLOCK EXT4_NDIR_BLOCKS
323 #define EXT4_DIND_BLOCK (EXT4_IND_BLOCK + 1)
324 #define EXT4_TIND_BLOCK (EXT4_DIND_BLOCK + 1)
325 #define EXT4_N_BLOCKS (EXT4_TIND_BLOCK + 1)
328 * Inode flags
330 #define EXT4_SECRM_FL 0x00000001 /* Secure deletion */
331 #define EXT4_UNRM_FL 0x00000002 /* Undelete */
332 #define EXT4_COMPR_FL 0x00000004 /* Compress file */
333 #define EXT4_SYNC_FL 0x00000008 /* Synchronous updates */
334 #define EXT4_IMMUTABLE_FL 0x00000010 /* Immutable file */
335 #define EXT4_APPEND_FL 0x00000020 /* writes to file may only append */
336 #define EXT4_NODUMP_FL 0x00000040 /* do not dump file */
337 #define EXT4_NOATIME_FL 0x00000080 /* do not update atime */
338 /* Reserved for compression usage... */
339 #define EXT4_DIRTY_FL 0x00000100
340 #define EXT4_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
341 #define EXT4_NOCOMPR_FL 0x00000400 /* Don't compress */
342 #define EXT4_ECOMPR_FL 0x00000800 /* Compression error */
343 /* End compression flags --- maybe not all used */
344 #define EXT4_INDEX_FL 0x00001000 /* hash-indexed directory */
345 #define EXT4_IMAGIC_FL 0x00002000 /* AFS directory */
346 #define EXT4_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
347 #define EXT4_NOTAIL_FL 0x00008000 /* file tail should not be merged */
348 #define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
349 #define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
350 #define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
351 #define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
352 #define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */
353 #define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */
354 #define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
356 #define EXT4_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */
357 #define EXT4_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */
359 /* Flags that should be inherited by new inodes from their parent. */
360 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
361 EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
362 EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
363 EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
364 EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
366 /* Flags that are appropriate for regular files (all but dir-specific ones). */
367 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
369 /* Flags that are appropriate for non-directories/regular files. */
370 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
372 /* Mask out flags that are inappropriate for the given type of inode. */
373 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
375 if (S_ISDIR(mode))
376 return flags;
377 else if (S_ISREG(mode))
378 return flags & EXT4_REG_FLMASK;
379 else
380 return flags & EXT4_OTHER_FLMASK;
384 * Inode flags used for atomic set/get
386 enum {
387 EXT4_INODE_SECRM = 0, /* Secure deletion */
388 EXT4_INODE_UNRM = 1, /* Undelete */
389 EXT4_INODE_COMPR = 2, /* Compress file */
390 EXT4_INODE_SYNC = 3, /* Synchronous updates */
391 EXT4_INODE_IMMUTABLE = 4, /* Immutable file */
392 EXT4_INODE_APPEND = 5, /* writes to file may only append */
393 EXT4_INODE_NODUMP = 6, /* do not dump file */
394 EXT4_INODE_NOATIME = 7, /* do not update atime */
395 /* Reserved for compression usage... */
396 EXT4_INODE_DIRTY = 8,
397 EXT4_INODE_COMPRBLK = 9, /* One or more compressed clusters */
398 EXT4_INODE_NOCOMPR = 10, /* Don't compress */
399 EXT4_INODE_ECOMPR = 11, /* Compression error */
400 /* End compression flags --- maybe not all used */
401 EXT4_INODE_INDEX = 12, /* hash-indexed directory */
402 EXT4_INODE_IMAGIC = 13, /* AFS directory */
403 EXT4_INODE_JOURNAL_DATA = 14, /* file data should be journaled */
404 EXT4_INODE_NOTAIL = 15, /* file tail should not be merged */
405 EXT4_INODE_DIRSYNC = 16, /* dirsync behaviour (directories only) */
406 EXT4_INODE_TOPDIR = 17, /* Top of directory hierarchies*/
407 EXT4_INODE_HUGE_FILE = 18, /* Set to each huge file */
408 EXT4_INODE_EXTENTS = 19, /* Inode uses extents */
409 EXT4_INODE_EA_INODE = 21, /* Inode used for large EA */
410 EXT4_INODE_EOFBLOCKS = 22, /* Blocks allocated beyond EOF */
411 EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */
414 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
415 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
416 printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
417 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
420 * Since it's pretty easy to mix up bit numbers and hex values, and we
421 * can't do a compile-time test for ENUM values, we use a run-time
422 * test to make sure that EXT4_XXX_FL is consistent with respect to
423 * EXT4_INODE_XXX. If all is well the printk and BUG_ON will all drop
424 * out so it won't cost any extra space in the compiled kernel image.
425 * But it's important that these values are the same, since we are
426 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
427 * must be consistent with the values of FS_XXX_FL defined in
428 * include/linux/fs.h and the on-disk values found in ext2, ext3, and
429 * ext4 filesystems, and of course the values defined in e2fsprogs.
431 * It's not paranoia if the Murphy's Law really *is* out to get you. :-)
433 static inline void ext4_check_flag_values(void)
435 CHECK_FLAG_VALUE(SECRM);
436 CHECK_FLAG_VALUE(UNRM);
437 CHECK_FLAG_VALUE(COMPR);
438 CHECK_FLAG_VALUE(SYNC);
439 CHECK_FLAG_VALUE(IMMUTABLE);
440 CHECK_FLAG_VALUE(APPEND);
441 CHECK_FLAG_VALUE(NODUMP);
442 CHECK_FLAG_VALUE(NOATIME);
443 CHECK_FLAG_VALUE(DIRTY);
444 CHECK_FLAG_VALUE(COMPRBLK);
445 CHECK_FLAG_VALUE(NOCOMPR);
446 CHECK_FLAG_VALUE(ECOMPR);
447 CHECK_FLAG_VALUE(INDEX);
448 CHECK_FLAG_VALUE(IMAGIC);
449 CHECK_FLAG_VALUE(JOURNAL_DATA);
450 CHECK_FLAG_VALUE(NOTAIL);
451 CHECK_FLAG_VALUE(DIRSYNC);
452 CHECK_FLAG_VALUE(TOPDIR);
453 CHECK_FLAG_VALUE(HUGE_FILE);
454 CHECK_FLAG_VALUE(EXTENTS);
455 CHECK_FLAG_VALUE(EA_INODE);
456 CHECK_FLAG_VALUE(EOFBLOCKS);
457 CHECK_FLAG_VALUE(RESERVED);
460 /* Used to pass group descriptor data when online resize is done */
461 struct ext4_new_group_input {
462 __u32 group; /* Group number for this data */
463 __u64 block_bitmap; /* Absolute block number of block bitmap */
464 __u64 inode_bitmap; /* Absolute block number of inode bitmap */
465 __u64 inode_table; /* Absolute block number of inode table start */
466 __u32 blocks_count; /* Total number of blocks in this group */
467 __u16 reserved_blocks; /* Number of reserved blocks in this group */
468 __u16 unused;
471 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
472 struct compat_ext4_new_group_input {
473 u32 group;
474 compat_u64 block_bitmap;
475 compat_u64 inode_bitmap;
476 compat_u64 inode_table;
477 u32 blocks_count;
478 u16 reserved_blocks;
479 u16 unused;
481 #endif
483 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
484 struct ext4_new_group_data {
485 __u32 group;
486 __u64 block_bitmap;
487 __u64 inode_bitmap;
488 __u64 inode_table;
489 __u32 blocks_count;
490 __u16 reserved_blocks;
491 __u16 unused;
492 __u32 free_blocks_count;
496 * Flags used by ext4_map_blocks()
498 /* Allocate any needed blocks and/or convert an unitialized
499 extent to be an initialized ext4 */
500 #define EXT4_GET_BLOCKS_CREATE 0x0001
501 /* Request the creation of an unitialized extent */
502 #define EXT4_GET_BLOCKS_UNINIT_EXT 0x0002
503 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT (EXT4_GET_BLOCKS_UNINIT_EXT|\
504 EXT4_GET_BLOCKS_CREATE)
505 /* Caller is from the delayed allocation writeout path,
506 so set the magic i_delalloc_reserve_flag after taking the
507 inode allocation semaphore for */
508 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE 0x0004
509 /* caller is from the direct IO path, request to creation of an
510 unitialized extents if not allocated, split the uninitialized
511 extent if blocks has been preallocated already*/
512 #define EXT4_GET_BLOCKS_PRE_IO 0x0008
513 #define EXT4_GET_BLOCKS_CONVERT 0x0010
514 #define EXT4_GET_BLOCKS_IO_CREATE_EXT (EXT4_GET_BLOCKS_PRE_IO|\
515 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
516 /* Convert extent to initialized after IO complete */
517 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT (EXT4_GET_BLOCKS_CONVERT|\
518 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
519 /* Punch out blocks of an extent */
520 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT 0x0020
521 /* Don't normalize allocation size (used for fallocate) */
522 #define EXT4_GET_BLOCKS_NO_NORMALIZE 0x0040
525 * Flags used by ext4_free_blocks
527 #define EXT4_FREE_BLOCKS_METADATA 0x0001
528 #define EXT4_FREE_BLOCKS_FORGET 0x0002
529 #define EXT4_FREE_BLOCKS_VALIDATED 0x0004
530 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
533 * ioctl commands
535 #define EXT4_IOC_GETFLAGS FS_IOC_GETFLAGS
536 #define EXT4_IOC_SETFLAGS FS_IOC_SETFLAGS
537 #define EXT4_IOC_GETVERSION _IOR('f', 3, long)
538 #define EXT4_IOC_SETVERSION _IOW('f', 4, long)
539 #define EXT4_IOC_GETVERSION_OLD FS_IOC_GETVERSION
540 #define EXT4_IOC_SETVERSION_OLD FS_IOC_SETVERSION
541 #ifdef CONFIG_JBD2_DEBUG
542 #define EXT4_IOC_WAIT_FOR_READONLY _IOR('f', 99, long)
543 #endif
544 #define EXT4_IOC_GETRSVSZ _IOR('f', 5, long)
545 #define EXT4_IOC_SETRSVSZ _IOW('f', 6, long)
546 #define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
547 #define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
548 #define EXT4_IOC_MIGRATE _IO('f', 9)
549 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
550 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
551 #define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12)
552 #define EXT4_IOC_MOVE_EXT _IOWR('f', 15, struct move_extent)
554 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
556 * ioctl commands in 32 bit emulation
558 #define EXT4_IOC32_GETFLAGS FS_IOC32_GETFLAGS
559 #define EXT4_IOC32_SETFLAGS FS_IOC32_SETFLAGS
560 #define EXT4_IOC32_GETVERSION _IOR('f', 3, int)
561 #define EXT4_IOC32_SETVERSION _IOW('f', 4, int)
562 #define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int)
563 #define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int)
564 #define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int)
565 #define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input)
566 #ifdef CONFIG_JBD2_DEBUG
567 #define EXT4_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int)
568 #endif
569 #define EXT4_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION
570 #define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
571 #endif
573 /* Max physical block we can address w/o extents */
574 #define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF
577 * Structure of an inode on the disk
579 struct ext4_inode {
580 __le16 i_mode; /* File mode */
581 __le16 i_uid; /* Low 16 bits of Owner Uid */
582 __le32 i_size_lo; /* Size in bytes */
583 __le32 i_atime; /* Access time */
584 __le32 i_ctime; /* Inode Change time */
585 __le32 i_mtime; /* Modification time */
586 __le32 i_dtime; /* Deletion Time */
587 __le16 i_gid; /* Low 16 bits of Group Id */
588 __le16 i_links_count; /* Links count */
589 __le32 i_blocks_lo; /* Blocks count */
590 __le32 i_flags; /* File flags */
591 union {
592 struct {
593 __le32 l_i_version;
594 } linux1;
595 struct {
596 __u32 h_i_translator;
597 } hurd1;
598 struct {
599 __u32 m_i_reserved1;
600 } masix1;
601 } osd1; /* OS dependent 1 */
602 __le32 i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
603 __le32 i_generation; /* File version (for NFS) */
604 __le32 i_file_acl_lo; /* File ACL */
605 __le32 i_size_high;
606 __le32 i_obso_faddr; /* Obsoleted fragment address */
607 union {
608 struct {
609 __le16 l_i_blocks_high; /* were l_i_reserved1 */
610 __le16 l_i_file_acl_high;
611 __le16 l_i_uid_high; /* these 2 fields */
612 __le16 l_i_gid_high; /* were reserved2[0] */
613 __u32 l_i_reserved2;
614 } linux2;
615 struct {
616 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
617 __u16 h_i_mode_high;
618 __u16 h_i_uid_high;
619 __u16 h_i_gid_high;
620 __u32 h_i_author;
621 } hurd2;
622 struct {
623 __le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
624 __le16 m_i_file_acl_high;
625 __u32 m_i_reserved2[2];
626 } masix2;
627 } osd2; /* OS dependent 2 */
628 __le16 i_extra_isize;
629 __le16 i_pad1;
630 __le32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
631 __le32 i_mtime_extra; /* extra Modification time(nsec << 2 | epoch) */
632 __le32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
633 __le32 i_crtime; /* File Creation time */
634 __le32 i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
635 __le32 i_version_hi; /* high 32 bits for 64-bit version */
638 struct move_extent {
639 __u32 reserved; /* should be zero */
640 __u32 donor_fd; /* donor file descriptor */
641 __u64 orig_start; /* logical start offset in block for orig */
642 __u64 donor_start; /* logical start offset in block for donor */
643 __u64 len; /* block length to be moved */
644 __u64 moved_len; /* moved block length */
647 #define EXT4_EPOCH_BITS 2
648 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
649 #define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS)
652 * Extended fields will fit into an inode if the filesystem was formatted
653 * with large inodes (-I 256 or larger) and there are not currently any EAs
654 * consuming all of the available space. For new inodes we always reserve
655 * enough space for the kernel's known extended fields, but for inodes
656 * created with an old kernel this might not have been the case. None of
657 * the extended inode fields is critical for correct filesystem operation.
658 * This macro checks if a certain field fits in the inode. Note that
659 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
661 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field) \
662 ((offsetof(typeof(*ext4_inode), field) + \
663 sizeof((ext4_inode)->field)) \
664 <= (EXT4_GOOD_OLD_INODE_SIZE + \
665 (einode)->i_extra_isize)) \
667 static inline __le32 ext4_encode_extra_time(struct timespec *time)
669 return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
670 (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
671 ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
674 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
676 if (sizeof(time->tv_sec) > 4)
677 time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
678 << 32;
679 time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
682 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode) \
683 do { \
684 (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \
685 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
686 (raw_inode)->xtime ## _extra = \
687 ext4_encode_extra_time(&(inode)->xtime); \
688 } while (0)
690 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \
691 do { \
692 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
693 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec); \
694 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
695 (raw_inode)->xtime ## _extra = \
696 ext4_encode_extra_time(&(einode)->xtime); \
697 } while (0)
699 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode) \
700 do { \
701 (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime); \
702 if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
703 ext4_decode_extra_time(&(inode)->xtime, \
704 raw_inode->xtime ## _extra); \
705 else \
706 (inode)->xtime.tv_nsec = 0; \
707 } while (0)
709 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode) \
710 do { \
711 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
712 (einode)->xtime.tv_sec = \
713 (signed)le32_to_cpu((raw_inode)->xtime); \
714 if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
715 ext4_decode_extra_time(&(einode)->xtime, \
716 raw_inode->xtime ## _extra); \
717 else \
718 (einode)->xtime.tv_nsec = 0; \
719 } while (0)
721 #define i_disk_version osd1.linux1.l_i_version
723 #if defined(__KERNEL__) || defined(__linux__)
724 #define i_reserved1 osd1.linux1.l_i_reserved1
725 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
726 #define i_blocks_high osd2.linux2.l_i_blocks_high
727 #define i_uid_low i_uid
728 #define i_gid_low i_gid
729 #define i_uid_high osd2.linux2.l_i_uid_high
730 #define i_gid_high osd2.linux2.l_i_gid_high
731 #define i_reserved2 osd2.linux2.l_i_reserved2
733 #elif defined(__GNU__)
735 #define i_translator osd1.hurd1.h_i_translator
736 #define i_uid_high osd2.hurd2.h_i_uid_high
737 #define i_gid_high osd2.hurd2.h_i_gid_high
738 #define i_author osd2.hurd2.h_i_author
740 #elif defined(__masix__)
742 #define i_reserved1 osd1.masix1.m_i_reserved1
743 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
744 #define i_reserved2 osd2.masix2.m_i_reserved2
746 #endif /* defined(__KERNEL__) || defined(__linux__) */
749 * storage for cached extent
750 * If ec_len == 0, then the cache is invalid.
751 * If ec_start == 0, then the cache represents a gap (null mapping)
753 struct ext4_ext_cache {
754 ext4_fsblk_t ec_start;
755 ext4_lblk_t ec_block;
756 __u32 ec_len; /* must be 32bit to return holes */
760 * fourth extended file system inode data in memory
762 struct ext4_inode_info {
763 __le32 i_data[15]; /* unconverted */
764 __u32 i_dtime;
765 ext4_fsblk_t i_file_acl;
768 * i_block_group is the number of the block group which contains
769 * this file's inode. Constant across the lifetime of the inode,
770 * it is ued for making block allocation decisions - we try to
771 * place a file's data blocks near its inode block, and new inodes
772 * near to their parent directory's inode.
774 ext4_group_t i_block_group;
775 ext4_lblk_t i_dir_start_lookup;
776 #if (BITS_PER_LONG < 64)
777 unsigned long i_state_flags; /* Dynamic state flags */
778 #endif
779 unsigned long i_flags;
781 #ifdef CONFIG_EXT4_FS_XATTR
783 * Extended attributes can be read independently of the main file
784 * data. Taking i_mutex even when reading would cause contention
785 * between readers of EAs and writers of regular file data, so
786 * instead we synchronize on xattr_sem when reading or changing
787 * EAs.
789 struct rw_semaphore xattr_sem;
790 #endif
792 struct list_head i_orphan; /* unlinked but open inodes */
795 * i_disksize keeps track of what the inode size is ON DISK, not
796 * in memory. During truncate, i_size is set to the new size by
797 * the VFS prior to calling ext4_truncate(), but the filesystem won't
798 * set i_disksize to 0 until the truncate is actually under way.
800 * The intent is that i_disksize always represents the blocks which
801 * are used by this file. This allows recovery to restart truncate
802 * on orphans if we crash during truncate. We actually write i_disksize
803 * into the on-disk inode when writing inodes out, instead of i_size.
805 * The only time when i_disksize and i_size may be different is when
806 * a truncate is in progress. The only things which change i_disksize
807 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
809 loff_t i_disksize;
812 * i_data_sem is for serialising ext4_truncate() against
813 * ext4_getblock(). In the 2.4 ext2 design, great chunks of inode's
814 * data tree are chopped off during truncate. We can't do that in
815 * ext4 because whenever we perform intermediate commits during
816 * truncate, the inode and all the metadata blocks *must* be in a
817 * consistent state which allows truncation of the orphans to restart
818 * during recovery. Hence we must fix the get_block-vs-truncate race
819 * by other means, so we have i_data_sem.
821 struct rw_semaphore i_data_sem;
822 struct inode vfs_inode;
823 struct jbd2_inode *jinode;
825 struct ext4_ext_cache i_cached_extent;
827 * File creation time. Its function is same as that of
828 * struct timespec i_{a,c,m}time in the generic inode.
830 struct timespec i_crtime;
832 /* mballoc */
833 struct list_head i_prealloc_list;
834 spinlock_t i_prealloc_lock;
836 /* ialloc */
837 ext4_group_t i_last_alloc_group;
839 /* allocation reservation info for delalloc */
840 unsigned int i_reserved_data_blocks;
841 unsigned int i_reserved_meta_blocks;
842 unsigned int i_allocated_meta_blocks;
843 ext4_lblk_t i_da_metadata_calc_last_lblock;
844 int i_da_metadata_calc_len;
846 /* on-disk additional length */
847 __u16 i_extra_isize;
849 #ifdef CONFIG_QUOTA
850 /* quota space reservation, managed internally by quota code */
851 qsize_t i_reserved_quota;
852 #endif
854 /* completed IOs that might need unwritten extents handling */
855 struct list_head i_completed_io_list;
856 spinlock_t i_completed_io_lock;
857 atomic_t i_ioend_count; /* Number of outstanding io_end structs */
858 /* current io_end structure for async DIO write*/
859 ext4_io_end_t *cur_aio_dio;
860 atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
862 spinlock_t i_block_reservation_lock;
865 * Transactions that contain inode's metadata needed to complete
866 * fsync and fdatasync, respectively.
868 tid_t i_sync_tid;
869 tid_t i_datasync_tid;
873 * File system states
875 #define EXT4_VALID_FS 0x0001 /* Unmounted cleanly */
876 #define EXT4_ERROR_FS 0x0002 /* Errors detected */
877 #define EXT4_ORPHAN_FS 0x0004 /* Orphans being recovered */
880 * Misc. filesystem flags
882 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
883 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
884 #define EXT2_FLAGS_TEST_FILESYS 0x0004 /* to test development code */
887 * Mount flags
889 #define EXT4_MOUNT_OLDALLOC 0x00002 /* Don't use the new Orlov allocator */
890 #define EXT4_MOUNT_GRPID 0x00004 /* Create files with directory's group */
891 #define EXT4_MOUNT_DEBUG 0x00008 /* Some debugging messages */
892 #define EXT4_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */
893 #define EXT4_MOUNT_ERRORS_RO 0x00020 /* Remount fs ro on errors */
894 #define EXT4_MOUNT_ERRORS_PANIC 0x00040 /* Panic on errors */
895 #define EXT4_MOUNT_MINIX_DF 0x00080 /* Mimics the Minix statfs */
896 #define EXT4_MOUNT_NOLOAD 0x00100 /* Don't use existing journal*/
897 #define EXT4_MOUNT_DATA_FLAGS 0x00C00 /* Mode for data writes: */
898 #define EXT4_MOUNT_JOURNAL_DATA 0x00400 /* Write data to journal */
899 #define EXT4_MOUNT_ORDERED_DATA 0x00800 /* Flush data before commit */
900 #define EXT4_MOUNT_WRITEBACK_DATA 0x00C00 /* No data ordering */
901 #define EXT4_MOUNT_UPDATE_JOURNAL 0x01000 /* Update the journal format */
902 #define EXT4_MOUNT_NO_UID32 0x02000 /* Disable 32-bit UIDs */
903 #define EXT4_MOUNT_XATTR_USER 0x04000 /* Extended user attributes */
904 #define EXT4_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */
905 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */
906 #define EXT4_MOUNT_BARRIER 0x20000 /* Use block barriers */
907 #define EXT4_MOUNT_QUOTA 0x80000 /* Some quota option set */
908 #define EXT4_MOUNT_USRQUOTA 0x100000 /* "old" user quota */
909 #define EXT4_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */
910 #define EXT4_MOUNT_DIOREAD_NOLOCK 0x400000 /* Enable support for dio read nolocking */
911 #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */
912 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
913 #define EXT4_MOUNT_I_VERSION 0x2000000 /* i_version support */
914 #define EXT4_MOUNT_MBLK_IO_SUBMIT 0x4000000 /* multi-block io submits */
915 #define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */
916 #define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */
917 #define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */
918 #define EXT4_MOUNT_DISCARD 0x40000000 /* Issue DISCARD requests */
919 #define EXT4_MOUNT_INIT_INODE_TABLE 0x80000000 /* Initialize uninitialized itables */
921 #define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \
922 ~EXT4_MOUNT_##opt
923 #define set_opt(sb, opt) EXT4_SB(sb)->s_mount_opt |= \
924 EXT4_MOUNT_##opt
925 #define test_opt(sb, opt) (EXT4_SB(sb)->s_mount_opt & \
926 EXT4_MOUNT_##opt)
928 #define clear_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 &= \
929 ~EXT4_MOUNT2_##opt
930 #define set_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 |= \
931 EXT4_MOUNT2_##opt
932 #define test_opt2(sb, opt) (EXT4_SB(sb)->s_mount_opt2 & \
933 EXT4_MOUNT2_##opt)
935 #define ext4_set_bit __test_and_set_bit_le
936 #define ext4_set_bit_atomic ext2_set_bit_atomic
937 #define ext4_clear_bit __test_and_clear_bit_le
938 #define ext4_clear_bit_atomic ext2_clear_bit_atomic
939 #define ext4_test_bit test_bit_le
940 #define ext4_find_first_zero_bit find_first_zero_bit_le
941 #define ext4_find_next_zero_bit find_next_zero_bit_le
942 #define ext4_find_next_bit find_next_bit_le
944 extern void ext4_set_bits(void *bm, int cur, int len);
947 * Maximal mount counts between two filesystem checks
949 #define EXT4_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
950 #define EXT4_DFL_CHECKINTERVAL 0 /* Don't use interval check */
953 * Behaviour when detecting errors
955 #define EXT4_ERRORS_CONTINUE 1 /* Continue execution */
956 #define EXT4_ERRORS_RO 2 /* Remount fs read-only */
957 #define EXT4_ERRORS_PANIC 3 /* Panic */
958 #define EXT4_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE
961 * Structure of the super block
963 struct ext4_super_block {
964 /*00*/ __le32 s_inodes_count; /* Inodes count */
965 __le32 s_blocks_count_lo; /* Blocks count */
966 __le32 s_r_blocks_count_lo; /* Reserved blocks count */
967 __le32 s_free_blocks_count_lo; /* Free blocks count */
968 /*10*/ __le32 s_free_inodes_count; /* Free inodes count */
969 __le32 s_first_data_block; /* First Data Block */
970 __le32 s_log_block_size; /* Block size */
971 __le32 s_obso_log_frag_size; /* Obsoleted fragment size */
972 /*20*/ __le32 s_blocks_per_group; /* # Blocks per group */
973 __le32 s_obso_frags_per_group; /* Obsoleted fragments per group */
974 __le32 s_inodes_per_group; /* # Inodes per group */
975 __le32 s_mtime; /* Mount time */
976 /*30*/ __le32 s_wtime; /* Write time */
977 __le16 s_mnt_count; /* Mount count */
978 __le16 s_max_mnt_count; /* Maximal mount count */
979 __le16 s_magic; /* Magic signature */
980 __le16 s_state; /* File system state */
981 __le16 s_errors; /* Behaviour when detecting errors */
982 __le16 s_minor_rev_level; /* minor revision level */
983 /*40*/ __le32 s_lastcheck; /* time of last check */
984 __le32 s_checkinterval; /* max. time between checks */
985 __le32 s_creator_os; /* OS */
986 __le32 s_rev_level; /* Revision level */
987 /*50*/ __le16 s_def_resuid; /* Default uid for reserved blocks */
988 __le16 s_def_resgid; /* Default gid for reserved blocks */
990 * These fields are for EXT4_DYNAMIC_REV superblocks only.
992 * Note: the difference between the compatible feature set and
993 * the incompatible feature set is that if there is a bit set
994 * in the incompatible feature set that the kernel doesn't
995 * know about, it should refuse to mount the filesystem.
997 * e2fsck's requirements are more strict; if it doesn't know
998 * about a feature in either the compatible or incompatible
999 * feature set, it must abort and not try to meddle with
1000 * things it doesn't understand...
1002 __le32 s_first_ino; /* First non-reserved inode */
1003 __le16 s_inode_size; /* size of inode structure */
1004 __le16 s_block_group_nr; /* block group # of this superblock */
1005 __le32 s_feature_compat; /* compatible feature set */
1006 /*60*/ __le32 s_feature_incompat; /* incompatible feature set */
1007 __le32 s_feature_ro_compat; /* readonly-compatible feature set */
1008 /*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */
1009 /*78*/ char s_volume_name[16]; /* volume name */
1010 /*88*/ char s_last_mounted[64]; /* directory where last mounted */
1011 /*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */
1013 * Performance hints. Directory preallocation should only
1014 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1016 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
1017 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
1018 __le16 s_reserved_gdt_blocks; /* Per group desc for online growth */
1020 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1022 /*D0*/ __u8 s_journal_uuid[16]; /* uuid of journal superblock */
1023 /*E0*/ __le32 s_journal_inum; /* inode number of journal file */
1024 __le32 s_journal_dev; /* device number of journal file */
1025 __le32 s_last_orphan; /* start of list of inodes to delete */
1026 __le32 s_hash_seed[4]; /* HTREE hash seed */
1027 __u8 s_def_hash_version; /* Default hash version to use */
1028 __u8 s_jnl_backup_type;
1029 __le16 s_desc_size; /* size of group descriptor */
1030 /*100*/ __le32 s_default_mount_opts;
1031 __le32 s_first_meta_bg; /* First metablock block group */
1032 __le32 s_mkfs_time; /* When the filesystem was created */
1033 __le32 s_jnl_blocks[17]; /* Backup of the journal inode */
1034 /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1035 /*150*/ __le32 s_blocks_count_hi; /* Blocks count */
1036 __le32 s_r_blocks_count_hi; /* Reserved blocks count */
1037 __le32 s_free_blocks_count_hi; /* Free blocks count */
1038 __le16 s_min_extra_isize; /* All inodes have at least # bytes */
1039 __le16 s_want_extra_isize; /* New inodes should reserve # bytes */
1040 __le32 s_flags; /* Miscellaneous flags */
1041 __le16 s_raid_stride; /* RAID stride */
1042 __le16 s_mmp_update_interval; /* # seconds to wait in MMP checking */
1043 __le64 s_mmp_block; /* Block for multi-mount protection */
1044 __le32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
1045 __u8 s_log_groups_per_flex; /* FLEX_BG group size */
1046 __u8 s_reserved_char_pad;
1047 __le16 s_reserved_pad;
1048 __le64 s_kbytes_written; /* nr of lifetime kilobytes written */
1049 __le32 s_snapshot_inum; /* Inode number of active snapshot */
1050 __le32 s_snapshot_id; /* sequential ID of active snapshot */
1051 __le64 s_snapshot_r_blocks_count; /* reserved blocks for active
1052 snapshot's future use */
1053 __le32 s_snapshot_list; /* inode number of the head of the
1054 on-disk snapshot list */
1055 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1056 __le32 s_error_count; /* number of fs errors */
1057 __le32 s_first_error_time; /* first time an error happened */
1058 __le32 s_first_error_ino; /* inode involved in first error */
1059 __le64 s_first_error_block; /* block involved of first error */
1060 __u8 s_first_error_func[32]; /* function where the error happened */
1061 __le32 s_first_error_line; /* line number where error happened */
1062 __le32 s_last_error_time; /* most recent time of an error */
1063 __le32 s_last_error_ino; /* inode involved in last error */
1064 __le32 s_last_error_line; /* line number where error happened */
1065 __le64 s_last_error_block; /* block involved of last error */
1066 __u8 s_last_error_func[32]; /* function where the error happened */
1067 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1068 __u8 s_mount_opts[64];
1069 __le32 s_reserved[112]; /* Padding to the end of the block */
1072 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1074 #ifdef __KERNEL__
1077 * run-time mount flags
1079 #define EXT4_MF_MNTDIR_SAMPLED 0x0001
1080 #define EXT4_MF_FS_ABORTED 0x0002 /* Fatal error detected */
1083 * fourth extended-fs super-block data in memory
1085 struct ext4_sb_info {
1086 unsigned long s_desc_size; /* Size of a group descriptor in bytes */
1087 unsigned long s_inodes_per_block;/* Number of inodes per block */
1088 unsigned long s_blocks_per_group;/* Number of blocks in a group */
1089 unsigned long s_inodes_per_group;/* Number of inodes in a group */
1090 unsigned long s_itb_per_group; /* Number of inode table blocks per group */
1091 unsigned long s_gdb_count; /* Number of group descriptor blocks */
1092 unsigned long s_desc_per_block; /* Number of group descriptors per block */
1093 ext4_group_t s_groups_count; /* Number of groups in the fs */
1094 ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1095 unsigned long s_overhead_last; /* Last calculated overhead */
1096 unsigned long s_blocks_last; /* Last seen block count */
1097 loff_t s_bitmap_maxbytes; /* max bytes for bitmap files */
1098 struct buffer_head * s_sbh; /* Buffer containing the super block */
1099 struct ext4_super_block *s_es; /* Pointer to the super block in the buffer */
1100 struct buffer_head **s_group_desc;
1101 unsigned int s_mount_opt;
1102 unsigned int s_mount_opt2;
1103 unsigned int s_mount_flags;
1104 ext4_fsblk_t s_sb_block;
1105 uid_t s_resuid;
1106 gid_t s_resgid;
1107 unsigned short s_mount_state;
1108 unsigned short s_pad;
1109 int s_addr_per_block_bits;
1110 int s_desc_per_block_bits;
1111 int s_inode_size;
1112 int s_first_ino;
1113 unsigned int s_inode_readahead_blks;
1114 unsigned int s_inode_goal;
1115 spinlock_t s_next_gen_lock;
1116 u32 s_next_generation;
1117 u32 s_hash_seed[4];
1118 int s_def_hash_version;
1119 int s_hash_unsigned; /* 3 if hash should be signed, 0 if not */
1120 struct percpu_counter s_freeblocks_counter;
1121 struct percpu_counter s_freeinodes_counter;
1122 struct percpu_counter s_dirs_counter;
1123 struct percpu_counter s_dirtyblocks_counter;
1124 struct blockgroup_lock *s_blockgroup_lock;
1125 struct proc_dir_entry *s_proc;
1126 struct kobject s_kobj;
1127 struct completion s_kobj_unregister;
1129 /* Journaling */
1130 struct journal_s *s_journal;
1131 struct list_head s_orphan;
1132 struct mutex s_orphan_lock;
1133 unsigned long s_resize_flags; /* Flags indicating if there
1134 is a resizer */
1135 unsigned long s_commit_interval;
1136 u32 s_max_batch_time;
1137 u32 s_min_batch_time;
1138 struct block_device *journal_bdev;
1139 #ifdef CONFIG_JBD2_DEBUG
1140 struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */
1141 wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */
1142 #endif
1143 #ifdef CONFIG_QUOTA
1144 char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
1145 int s_jquota_fmt; /* Format of quota to use */
1146 #endif
1147 unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1148 struct rb_root system_blks;
1150 #ifdef EXTENTS_STATS
1151 /* ext4 extents stats */
1152 unsigned long s_ext_min;
1153 unsigned long s_ext_max;
1154 unsigned long s_depth_max;
1155 spinlock_t s_ext_stats_lock;
1156 unsigned long s_ext_blocks;
1157 unsigned long s_ext_extents;
1158 #endif
1159 /* ext4 extent cache stats */
1160 unsigned long extent_cache_hits;
1161 unsigned long extent_cache_misses;
1163 /* for buddy allocator */
1164 struct ext4_group_info ***s_group_info;
1165 struct inode *s_buddy_cache;
1166 spinlock_t s_md_lock;
1167 unsigned short *s_mb_offsets;
1168 unsigned int *s_mb_maxs;
1170 /* tunables */
1171 unsigned long s_stripe;
1172 unsigned int s_mb_stream_request;
1173 unsigned int s_mb_max_to_scan;
1174 unsigned int s_mb_min_to_scan;
1175 unsigned int s_mb_stats;
1176 unsigned int s_mb_order2_reqs;
1177 unsigned int s_mb_group_prealloc;
1178 unsigned int s_max_writeback_mb_bump;
1179 /* where last allocation was done - for stream allocation */
1180 unsigned long s_mb_last_group;
1181 unsigned long s_mb_last_start;
1183 /* stats for buddy allocator */
1184 atomic_t s_bal_reqs; /* number of reqs with len > 1 */
1185 atomic_t s_bal_success; /* we found long enough chunks */
1186 atomic_t s_bal_allocated; /* in blocks */
1187 atomic_t s_bal_ex_scanned; /* total extents scanned */
1188 atomic_t s_bal_goals; /* goal hits */
1189 atomic_t s_bal_breaks; /* too long searches */
1190 atomic_t s_bal_2orders; /* 2^order hits */
1191 spinlock_t s_bal_lock;
1192 unsigned long s_mb_buddies_generated;
1193 unsigned long long s_mb_generation_time;
1194 atomic_t s_mb_lost_chunks;
1195 atomic_t s_mb_preallocated;
1196 atomic_t s_mb_discarded;
1197 atomic_t s_lock_busy;
1199 /* locality groups */
1200 struct ext4_locality_group __percpu *s_locality_groups;
1202 /* for write statistics */
1203 unsigned long s_sectors_written_start;
1204 u64 s_kbytes_written;
1206 unsigned int s_log_groups_per_flex;
1207 struct flex_groups *s_flex_groups;
1209 /* workqueue for dio unwritten */
1210 struct workqueue_struct *dio_unwritten_wq;
1212 /* timer for periodic error stats printing */
1213 struct timer_list s_err_report;
1215 /* Lazy inode table initialization info */
1216 struct ext4_li_request *s_li_request;
1217 /* Wait multiplier for lazy initialization thread */
1218 unsigned int s_li_wait_mult;
1220 /* Kernel thread for multiple mount protection */
1221 struct task_struct *s_mmp_tsk;
1223 /* record the last minlen when FITRIM is called. */
1224 atomic_t s_last_trim_minblks;
1227 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1229 return sb->s_fs_info;
1231 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1233 return container_of(inode, struct ext4_inode_info, vfs_inode);
1236 static inline struct timespec ext4_current_time(struct inode *inode)
1238 return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1239 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1242 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1244 return ino == EXT4_ROOT_INO ||
1245 ino == EXT4_JOURNAL_INO ||
1246 ino == EXT4_RESIZE_INO ||
1247 (ino >= EXT4_FIRST_INO(sb) &&
1248 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1252 * Inode dynamic state flags
1254 enum {
1255 EXT4_STATE_JDATA, /* journaled data exists */
1256 EXT4_STATE_NEW, /* inode is newly created */
1257 EXT4_STATE_XATTR, /* has in-inode xattrs */
1258 EXT4_STATE_NO_EXPAND, /* No space for expansion */
1259 EXT4_STATE_DA_ALLOC_CLOSE, /* Alloc DA blks on close */
1260 EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */
1261 EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/
1262 EXT4_STATE_NEWENTRY, /* File just added to dir */
1263 EXT4_STATE_DELALLOC_RESERVED, /* blks already reserved for delalloc */
1266 #define EXT4_INODE_BIT_FNS(name, field, offset) \
1267 static inline int ext4_test_inode_##name(struct inode *inode, int bit) \
1269 return test_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1271 static inline void ext4_set_inode_##name(struct inode *inode, int bit) \
1273 set_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1275 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1277 clear_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1280 EXT4_INODE_BIT_FNS(flag, flags, 0)
1281 #if (BITS_PER_LONG < 64)
1282 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1284 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1286 (ei)->i_state_flags = 0;
1288 #else
1289 EXT4_INODE_BIT_FNS(state, flags, 32)
1291 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1293 /* We depend on the fact that callers will set i_flags */
1295 #endif
1296 #else
1297 /* Assume that user mode programs are passing in an ext4fs superblock, not
1298 * a kernel struct super_block. This will allow us to call the feature-test
1299 * macros from user land. */
1300 #define EXT4_SB(sb) (sb)
1301 #endif
1303 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1306 * Codes for operating systems
1308 #define EXT4_OS_LINUX 0
1309 #define EXT4_OS_HURD 1
1310 #define EXT4_OS_MASIX 2
1311 #define EXT4_OS_FREEBSD 3
1312 #define EXT4_OS_LITES 4
1315 * Revision levels
1317 #define EXT4_GOOD_OLD_REV 0 /* The good old (original) format */
1318 #define EXT4_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
1320 #define EXT4_CURRENT_REV EXT4_GOOD_OLD_REV
1321 #define EXT4_MAX_SUPP_REV EXT4_DYNAMIC_REV
1323 #define EXT4_GOOD_OLD_INODE_SIZE 128
1326 * Feature set definitions
1329 #define EXT4_HAS_COMPAT_FEATURE(sb,mask) \
1330 ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1331 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask) \
1332 ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1333 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask) \
1334 ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1335 #define EXT4_SET_COMPAT_FEATURE(sb,mask) \
1336 EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1337 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask) \
1338 EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1339 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask) \
1340 EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1341 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask) \
1342 EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1343 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
1344 EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1345 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask) \
1346 EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1348 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001
1349 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002
1350 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004
1351 #define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008
1352 #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010
1353 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020
1355 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
1356 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
1357 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
1358 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
1359 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
1360 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
1361 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
1362 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
1364 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
1365 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
1366 #define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
1367 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
1368 #define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
1369 #define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
1370 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
1371 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
1372 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
1373 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */
1374 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */
1376 #define EXT2_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
1377 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1378 EXT4_FEATURE_INCOMPAT_META_BG)
1379 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1380 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1381 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1383 #define EXT3_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
1384 #define EXT3_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1385 EXT4_FEATURE_INCOMPAT_RECOVER| \
1386 EXT4_FEATURE_INCOMPAT_META_BG)
1387 #define EXT3_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1388 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1389 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1391 #define EXT4_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
1392 #define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1393 EXT4_FEATURE_INCOMPAT_RECOVER| \
1394 EXT4_FEATURE_INCOMPAT_META_BG| \
1395 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1396 EXT4_FEATURE_INCOMPAT_64BIT| \
1397 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1398 EXT4_FEATURE_INCOMPAT_MMP)
1399 #define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1400 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1401 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1402 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1403 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1404 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1405 EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1408 * Default values for user and/or group using reserved blocks
1410 #define EXT4_DEF_RESUID 0
1411 #define EXT4_DEF_RESGID 0
1413 #define EXT4_DEF_INODE_READAHEAD_BLKS 32
1416 * Default mount options
1418 #define EXT4_DEFM_DEBUG 0x0001
1419 #define EXT4_DEFM_BSDGROUPS 0x0002
1420 #define EXT4_DEFM_XATTR_USER 0x0004
1421 #define EXT4_DEFM_ACL 0x0008
1422 #define EXT4_DEFM_UID16 0x0010
1423 #define EXT4_DEFM_JMODE 0x0060
1424 #define EXT4_DEFM_JMODE_DATA 0x0020
1425 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1426 #define EXT4_DEFM_JMODE_WBACK 0x0060
1427 #define EXT4_DEFM_NOBARRIER 0x0100
1428 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1429 #define EXT4_DEFM_DISCARD 0x0400
1430 #define EXT4_DEFM_NODELALLOC 0x0800
1433 * Default journal batch times
1435 #define EXT4_DEF_MIN_BATCH_TIME 0
1436 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1439 * Minimum number of groups in a flexgroup before we separate out
1440 * directories into the first block group of a flexgroup
1442 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1445 * Structure of a directory entry
1447 #define EXT4_NAME_LEN 255
1449 struct ext4_dir_entry {
1450 __le32 inode; /* Inode number */
1451 __le16 rec_len; /* Directory entry length */
1452 __le16 name_len; /* Name length */
1453 char name[EXT4_NAME_LEN]; /* File name */
1457 * The new version of the directory entry. Since EXT4 structures are
1458 * stored in intel byte order, and the name_len field could never be
1459 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1460 * file_type field.
1462 struct ext4_dir_entry_2 {
1463 __le32 inode; /* Inode number */
1464 __le16 rec_len; /* Directory entry length */
1465 __u8 name_len; /* Name length */
1466 __u8 file_type;
1467 char name[EXT4_NAME_LEN]; /* File name */
1471 * Ext4 directory file types. Only the low 3 bits are used. The
1472 * other bits are reserved for now.
1474 #define EXT4_FT_UNKNOWN 0
1475 #define EXT4_FT_REG_FILE 1
1476 #define EXT4_FT_DIR 2
1477 #define EXT4_FT_CHRDEV 3
1478 #define EXT4_FT_BLKDEV 4
1479 #define EXT4_FT_FIFO 5
1480 #define EXT4_FT_SOCK 6
1481 #define EXT4_FT_SYMLINK 7
1483 #define EXT4_FT_MAX 8
1486 * EXT4_DIR_PAD defines the directory entries boundaries
1488 * NOTE: It must be a multiple of 4
1490 #define EXT4_DIR_PAD 4
1491 #define EXT4_DIR_ROUND (EXT4_DIR_PAD - 1)
1492 #define EXT4_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT4_DIR_ROUND) & \
1493 ~EXT4_DIR_ROUND)
1494 #define EXT4_MAX_REC_LEN ((1<<16)-1)
1497 * If we ever get support for fs block sizes > page_size, we'll need
1498 * to remove the #if statements in the next two functions...
1500 static inline unsigned int
1501 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1503 unsigned len = le16_to_cpu(dlen);
1505 #if (PAGE_CACHE_SIZE >= 65536)
1506 if (len == EXT4_MAX_REC_LEN || len == 0)
1507 return blocksize;
1508 return (len & 65532) | ((len & 3) << 16);
1509 #else
1510 return len;
1511 #endif
1514 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1516 if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1517 BUG();
1518 #if (PAGE_CACHE_SIZE >= 65536)
1519 if (len < 65536)
1520 return cpu_to_le16(len);
1521 if (len == blocksize) {
1522 if (blocksize == 65536)
1523 return cpu_to_le16(EXT4_MAX_REC_LEN);
1524 else
1525 return cpu_to_le16(0);
1527 return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1528 #else
1529 return cpu_to_le16(len);
1530 #endif
1534 * Hash Tree Directory indexing
1535 * (c) Daniel Phillips, 2001
1538 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1539 EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1540 ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1541 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1542 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1544 /* Legal values for the dx_root hash_version field: */
1546 #define DX_HASH_LEGACY 0
1547 #define DX_HASH_HALF_MD4 1
1548 #define DX_HASH_TEA 2
1549 #define DX_HASH_LEGACY_UNSIGNED 3
1550 #define DX_HASH_HALF_MD4_UNSIGNED 4
1551 #define DX_HASH_TEA_UNSIGNED 5
1553 #ifdef __KERNEL__
1555 /* hash info structure used by the directory hash */
1556 struct dx_hash_info
1558 u32 hash;
1559 u32 minor_hash;
1560 int hash_version;
1561 u32 *seed;
1564 #define EXT4_HTREE_EOF 0x7fffffff
1567 * Control parameters used by ext4_htree_next_block
1569 #define HASH_NB_ALWAYS 1
1573 * Describe an inode's exact location on disk and in memory
1575 struct ext4_iloc
1577 struct buffer_head *bh;
1578 unsigned long offset;
1579 ext4_group_t block_group;
1582 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1584 return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1588 * This structure is stuffed into the struct file's private_data field
1589 * for directories. It is where we put information so that we can do
1590 * readdir operations in hash tree order.
1592 struct dir_private_info {
1593 struct rb_root root;
1594 struct rb_node *curr_node;
1595 struct fname *extra_fname;
1596 loff_t last_pos;
1597 __u32 curr_hash;
1598 __u32 curr_minor_hash;
1599 __u32 next_hash;
1602 /* calculate the first block number of the group */
1603 static inline ext4_fsblk_t
1604 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1606 return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1607 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1611 * Special error return code only used by dx_probe() and its callers.
1613 #define ERR_BAD_DX_DIR -75000
1615 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1616 ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1619 * Timeout and state flag for lazy initialization inode thread.
1621 #define EXT4_DEF_LI_WAIT_MULT 10
1622 #define EXT4_DEF_LI_MAX_START_DELAY 5
1623 #define EXT4_LAZYINIT_QUIT 0x0001
1624 #define EXT4_LAZYINIT_RUNNING 0x0002
1627 * Lazy inode table initialization info
1629 struct ext4_lazy_init {
1630 unsigned long li_state;
1631 struct list_head li_request_list;
1632 struct mutex li_list_mtx;
1635 struct ext4_li_request {
1636 struct super_block *lr_super;
1637 struct ext4_sb_info *lr_sbi;
1638 ext4_group_t lr_next_group;
1639 struct list_head lr_request;
1640 unsigned long lr_next_sched;
1641 unsigned long lr_timeout;
1644 struct ext4_features {
1645 struct kobject f_kobj;
1646 struct completion f_kobj_unregister;
1650 * This structure will be used for multiple mount protection. It will be
1651 * written into the block number saved in the s_mmp_block field in the
1652 * superblock. Programs that check MMP should assume that if
1653 * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1654 * to use the filesystem, regardless of how old the timestamp is.
1656 #define EXT4_MMP_MAGIC 0x004D4D50U /* ASCII for MMP */
1657 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1658 #define EXT4_MMP_SEQ_FSCK 0xE24D4D50U /* mmp_seq value when being fscked */
1659 #define EXT4_MMP_SEQ_MAX 0xE24D4D4FU /* maximum valid mmp_seq value */
1661 struct mmp_struct {
1662 __le32 mmp_magic; /* Magic number for MMP */
1663 __le32 mmp_seq; /* Sequence no. updated periodically */
1666 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1667 * purposes and do not affect the correctness of the algorithm
1669 __le64 mmp_time; /* Time last updated */
1670 char mmp_nodename[64]; /* Node which last updated MMP block */
1671 char mmp_bdevname[32]; /* Bdev which last updated MMP block */
1674 * mmp_check_interval is used to verify if the MMP block has been
1675 * updated on the block device. The value is updated based on the
1676 * maximum time to write the MMP block during an update cycle.
1678 __le16 mmp_check_interval;
1680 __le16 mmp_pad1;
1681 __le32 mmp_pad2[227];
1684 /* arguments passed to the mmp thread */
1685 struct mmpd_data {
1686 struct buffer_head *bh; /* bh from initial read_mmp_block() */
1687 struct super_block *sb; /* super block of the fs */
1691 * Check interval multiplier
1692 * The MMP block is written every update interval and initially checked every
1693 * update interval x the multiplier (the value is then adapted based on the
1694 * write latency). The reason is that writes can be delayed under load and we
1695 * don't want readers to incorrectly assume that the filesystem is no longer
1696 * in use.
1698 #define EXT4_MMP_CHECK_MULT 2UL
1701 * Minimum interval for MMP checking in seconds.
1703 #define EXT4_MMP_MIN_CHECK_INTERVAL 5UL
1706 * Maximum interval for MMP checking in seconds.
1708 #define EXT4_MMP_MAX_CHECK_INTERVAL 300UL
1711 * Function prototypes
1715 * Ok, these declarations are also in <linux/kernel.h> but none of the
1716 * ext4 source programs needs to include it so they are duplicated here.
1718 # define NORET_TYPE /**/
1719 # define ATTRIB_NORET __attribute__((noreturn))
1720 # define NORET_AND noreturn,
1722 /* bitmap.c */
1723 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1725 /* balloc.c */
1726 extern unsigned int ext4_block_group(struct super_block *sb,
1727 ext4_fsblk_t blocknr);
1728 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1729 ext4_fsblk_t blocknr);
1730 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1731 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1732 ext4_group_t group);
1733 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1734 ext4_fsblk_t goal,
1735 unsigned int flags,
1736 unsigned long *count,
1737 int *errp);
1738 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
1739 s64 nblocks, unsigned int flags);
1740 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1741 extern void ext4_check_blocks_bitmap(struct super_block *);
1742 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1743 ext4_group_t block_group,
1744 struct buffer_head ** bh);
1745 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1746 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1747 ext4_group_t block_group);
1748 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1749 struct buffer_head *bh,
1750 ext4_group_t group,
1751 struct ext4_group_desc *desc);
1752 #define ext4_free_blocks_after_init(sb, group, desc) \
1753 ext4_init_block_bitmap(sb, NULL, group, desc)
1754 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1756 /* dir.c */
1757 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1758 struct file *,
1759 struct ext4_dir_entry_2 *,
1760 struct buffer_head *, unsigned int);
1761 #define ext4_check_dir_entry(dir, filp, de, bh, offset) \
1762 unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1763 (de), (bh), (offset)))
1764 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1765 __u32 minor_hash,
1766 struct ext4_dir_entry_2 *dirent);
1767 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1769 /* fsync.c */
1770 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1771 extern int ext4_flush_completed_IO(struct inode *);
1773 /* hash.c */
1774 extern int ext4fs_dirhash(const char *name, int len, struct
1775 dx_hash_info *hinfo);
1777 /* ialloc.c */
1778 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1779 const struct qstr *qstr, __u32 goal);
1780 extern void ext4_free_inode(handle_t *, struct inode *);
1781 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1782 extern unsigned long ext4_count_free_inodes(struct super_block *);
1783 extern unsigned long ext4_count_dirs(struct super_block *);
1784 extern void ext4_check_inodes_bitmap(struct super_block *);
1785 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1786 extern int ext4_init_inode_table(struct super_block *sb,
1787 ext4_group_t group, int barrier);
1789 /* mballoc.c */
1790 extern long ext4_mb_stats;
1791 extern long ext4_mb_max_to_scan;
1792 extern int ext4_mb_init(struct super_block *, int);
1793 extern int ext4_mb_release(struct super_block *);
1794 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1795 struct ext4_allocation_request *, int *);
1796 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1797 extern void ext4_discard_preallocations(struct inode *);
1798 extern int __init ext4_init_mballoc(void);
1799 extern void ext4_exit_mballoc(void);
1800 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1801 struct buffer_head *bh, ext4_fsblk_t block,
1802 unsigned long count, int flags);
1803 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1804 ext4_group_t i, struct ext4_group_desc *desc);
1805 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1806 ext4_fsblk_t block, unsigned long count);
1807 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1809 /* inode.c */
1810 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1811 ext4_lblk_t, int, int *);
1812 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1813 ext4_lblk_t, int, int *);
1814 int ext4_get_block(struct inode *inode, sector_t iblock,
1815 struct buffer_head *bh_result, int create);
1817 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1818 extern int ext4_write_inode(struct inode *, struct writeback_control *);
1819 extern int ext4_setattr(struct dentry *, struct iattr *);
1820 extern int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1821 struct kstat *stat);
1822 extern void ext4_evict_inode(struct inode *);
1823 extern void ext4_clear_inode(struct inode *);
1824 extern int ext4_sync_inode(handle_t *, struct inode *);
1825 extern void ext4_dirty_inode(struct inode *, int);
1826 extern int ext4_change_inode_journal_flag(struct inode *, int);
1827 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1828 extern int ext4_can_truncate(struct inode *inode);
1829 extern void ext4_truncate(struct inode *);
1830 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1831 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1832 extern void ext4_set_inode_flags(struct inode *);
1833 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1834 extern int ext4_alloc_da_blocks(struct inode *inode);
1835 extern void ext4_set_aops(struct inode *inode);
1836 extern int ext4_writepage_trans_blocks(struct inode *);
1837 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1838 extern int ext4_block_truncate_page(handle_t *handle,
1839 struct address_space *mapping, loff_t from);
1840 extern int ext4_block_zero_page_range(handle_t *handle,
1841 struct address_space *mapping, loff_t from, loff_t length);
1842 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1843 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1844 extern void ext4_da_update_reserve_space(struct inode *inode,
1845 int used, int quota_claim);
1847 /* indirect.c */
1848 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
1849 struct ext4_map_blocks *map, int flags);
1850 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
1851 const struct iovec *iov, loff_t offset,
1852 unsigned long nr_segs);
1853 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
1854 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
1855 extern void ext4_ind_truncate(struct inode *inode);
1857 /* ioctl.c */
1858 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1859 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1861 /* migrate.c */
1862 extern int ext4_ext_migrate(struct inode *);
1864 /* namei.c */
1865 extern int ext4_orphan_add(handle_t *, struct inode *);
1866 extern int ext4_orphan_del(handle_t *, struct inode *);
1867 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1868 __u32 start_minor_hash, __u32 *next_hash);
1870 /* resize.c */
1871 extern int ext4_group_add(struct super_block *sb,
1872 struct ext4_new_group_data *input);
1873 extern int ext4_group_extend(struct super_block *sb,
1874 struct ext4_super_block *es,
1875 ext4_fsblk_t n_blocks_count);
1877 /* super.c */
1878 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
1879 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
1880 extern void ext4_kvfree(void *ptr);
1881 extern void __ext4_error(struct super_block *, const char *, unsigned int,
1882 const char *, ...)
1883 __attribute__ ((format (printf, 4, 5)));
1884 #define ext4_error(sb, message...) __ext4_error(sb, __func__, \
1885 __LINE__, ## message)
1886 extern void ext4_error_inode(struct inode *, const char *, unsigned int,
1887 ext4_fsblk_t, const char *, ...)
1888 __attribute__ ((format (printf, 5, 6)));
1889 extern void ext4_error_file(struct file *, const char *, unsigned int,
1890 ext4_fsblk_t, const char *, ...)
1891 __attribute__ ((format (printf, 5, 6)));
1892 extern void __ext4_std_error(struct super_block *, const char *,
1893 unsigned int, int);
1894 extern void __ext4_abort(struct super_block *, const char *, unsigned int,
1895 const char *, ...)
1896 __attribute__ ((format (printf, 4, 5)));
1897 #define ext4_abort(sb, message...) __ext4_abort(sb, __func__, \
1898 __LINE__, ## message)
1899 extern void __ext4_warning(struct super_block *, const char *, unsigned int,
1900 const char *, ...)
1901 __attribute__ ((format (printf, 4, 5)));
1902 #define ext4_warning(sb, message...) __ext4_warning(sb, __func__, \
1903 __LINE__, ## message)
1904 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1905 __attribute__ ((format (printf, 3, 4)));
1906 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
1907 const char *, unsigned int, const char *);
1908 #define dump_mmp_msg(sb, mmp, msg) __dump_mmp_msg(sb, mmp, __func__, \
1909 __LINE__, msg)
1910 extern void __ext4_grp_locked_error(const char *, unsigned int, \
1911 struct super_block *, ext4_group_t, \
1912 unsigned long, ext4_fsblk_t, \
1913 const char *, ...)
1914 __attribute__ ((format (printf, 7, 8)));
1915 #define ext4_grp_locked_error(sb, grp, message...) \
1916 __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1917 extern void ext4_update_dynamic_rev(struct super_block *sb);
1918 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1919 __u32 compat);
1920 extern int ext4_update_rocompat_feature(handle_t *handle,
1921 struct super_block *sb, __u32 rocompat);
1922 extern int ext4_update_incompat_feature(handle_t *handle,
1923 struct super_block *sb, __u32 incompat);
1924 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1925 struct ext4_group_desc *bg);
1926 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1927 struct ext4_group_desc *bg);
1928 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1929 struct ext4_group_desc *bg);
1930 extern __u32 ext4_free_blks_count(struct super_block *sb,
1931 struct ext4_group_desc *bg);
1932 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1933 struct ext4_group_desc *bg);
1934 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1935 struct ext4_group_desc *bg);
1936 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1937 struct ext4_group_desc *bg);
1938 extern void ext4_block_bitmap_set(struct super_block *sb,
1939 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1940 extern void ext4_inode_bitmap_set(struct super_block *sb,
1941 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1942 extern void ext4_inode_table_set(struct super_block *sb,
1943 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1944 extern void ext4_free_blks_set(struct super_block *sb,
1945 struct ext4_group_desc *bg, __u32 count);
1946 extern void ext4_free_inodes_set(struct super_block *sb,
1947 struct ext4_group_desc *bg, __u32 count);
1948 extern void ext4_used_dirs_set(struct super_block *sb,
1949 struct ext4_group_desc *bg, __u32 count);
1950 extern void ext4_itable_unused_set(struct super_block *sb,
1951 struct ext4_group_desc *bg, __u32 count);
1952 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1953 struct ext4_group_desc *gdp);
1954 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1955 struct ext4_group_desc *gdp);
1957 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1959 return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1960 le32_to_cpu(es->s_blocks_count_lo);
1963 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1965 return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1966 le32_to_cpu(es->s_r_blocks_count_lo);
1969 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1971 return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1972 le32_to_cpu(es->s_free_blocks_count_lo);
1975 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1976 ext4_fsblk_t blk)
1978 es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1979 es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1982 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1983 ext4_fsblk_t blk)
1985 es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1986 es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1989 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1990 ext4_fsblk_t blk)
1992 es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1993 es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1996 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1998 if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1999 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2000 le32_to_cpu(raw_inode->i_size_lo);
2001 else
2002 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2005 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2007 raw_inode->i_size_lo = cpu_to_le32(i_size);
2008 raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2011 static inline
2012 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2013 ext4_group_t group)
2015 struct ext4_group_info ***grp_info;
2016 long indexv, indexh;
2017 grp_info = EXT4_SB(sb)->s_group_info;
2018 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2019 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2020 return grp_info[indexv][indexh];
2024 * Reading s_groups_count requires using smp_rmb() afterwards. See
2025 * the locking protocol documented in the comments of ext4_group_add()
2026 * in resize.c
2028 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2030 ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2032 smp_rmb();
2033 return ngroups;
2036 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2037 ext4_group_t block_group)
2039 return block_group >> sbi->s_log_groups_per_flex;
2042 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2044 return 1 << sbi->s_log_groups_per_flex;
2047 #define ext4_std_error(sb, errno) \
2048 do { \
2049 if ((errno)) \
2050 __ext4_std_error((sb), __func__, __LINE__, (errno)); \
2051 } while (0)
2053 #ifdef CONFIG_SMP
2054 /* Each CPU can accumulate percpu_counter_batch blocks in their local
2055 * counters. So we need to make sure we have free blocks more
2056 * than percpu_counter_batch * nr_cpu_ids. Also add a window of 4 times.
2058 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2059 #else
2060 #define EXT4_FREEBLOCKS_WATERMARK 0
2061 #endif
2063 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2066 * XXX: replace with spinlock if seen contended -bzzz
2068 down_write(&EXT4_I(inode)->i_data_sem);
2069 if (newsize > EXT4_I(inode)->i_disksize)
2070 EXT4_I(inode)->i_disksize = newsize;
2071 up_write(&EXT4_I(inode)->i_data_sem);
2072 return ;
2075 struct ext4_group_info {
2076 unsigned long bb_state;
2077 struct rb_root bb_free_root;
2078 ext4_grpblk_t bb_first_free; /* first free block */
2079 ext4_grpblk_t bb_free; /* total free blocks */
2080 ext4_grpblk_t bb_fragments; /* nr of freespace fragments */
2081 ext4_grpblk_t bb_largest_free_order;/* order of largest frag in BG */
2082 struct list_head bb_prealloc_list;
2083 #ifdef DOUBLE_CHECK
2084 void *bb_bitmap;
2085 #endif
2086 struct rw_semaphore alloc_sem;
2087 ext4_grpblk_t bb_counters[]; /* Nr of free power-of-two-block
2088 * regions, index is order.
2089 * bb_counters[3] = 5 means
2090 * 5 free 8-block regions. */
2093 #define EXT4_GROUP_INFO_NEED_INIT_BIT 0
2094 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT 1
2096 #define EXT4_MB_GRP_NEED_INIT(grp) \
2097 (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2099 #define EXT4_MB_GRP_WAS_TRIMMED(grp) \
2100 (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2101 #define EXT4_MB_GRP_SET_TRIMMED(grp) \
2102 (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2103 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp) \
2104 (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2106 #define EXT4_MAX_CONTENTION 8
2107 #define EXT4_CONTENTION_THRESHOLD 2
2109 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2110 ext4_group_t group)
2112 return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2116 * Returns true if the filesystem is busy enough that attempts to
2117 * access the block group locks has run into contention.
2119 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2121 return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2124 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2126 spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2127 if (spin_trylock(lock))
2129 * We're able to grab the lock right away, so drop the
2130 * lock contention counter.
2132 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2133 else {
2135 * The lock is busy, so bump the contention counter,
2136 * and then wait on the spin lock.
2138 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2139 EXT4_MAX_CONTENTION);
2140 spin_lock(lock);
2144 static inline void ext4_unlock_group(struct super_block *sb,
2145 ext4_group_t group)
2147 spin_unlock(ext4_group_lock_ptr(sb, group));
2150 static inline void ext4_mark_super_dirty(struct super_block *sb)
2152 if (EXT4_SB(sb)->s_journal == NULL)
2153 sb->s_dirt =1;
2157 * Block validity checking
2159 #define ext4_check_indirect_blockref(inode, bh) \
2160 ext4_check_blockref(__func__, __LINE__, inode, \
2161 (__le32 *)(bh)->b_data, \
2162 EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2164 #define ext4_ind_check_inode(inode) \
2165 ext4_check_blockref(__func__, __LINE__, inode, \
2166 EXT4_I(inode)->i_data, \
2167 EXT4_NDIR_BLOCKS)
2170 * Inodes and files operations
2173 /* dir.c */
2174 extern const struct file_operations ext4_dir_operations;
2176 /* file.c */
2177 extern const struct inode_operations ext4_file_inode_operations;
2178 extern const struct file_operations ext4_file_operations;
2179 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2181 /* namei.c */
2182 extern const struct inode_operations ext4_dir_inode_operations;
2183 extern const struct inode_operations ext4_special_inode_operations;
2184 extern struct dentry *ext4_get_parent(struct dentry *child);
2186 /* symlink.c */
2187 extern const struct inode_operations ext4_symlink_inode_operations;
2188 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2190 /* block_validity */
2191 extern void ext4_release_system_zone(struct super_block *sb);
2192 extern int ext4_setup_system_zone(struct super_block *sb);
2193 extern int __init ext4_init_system_zone(void);
2194 extern void ext4_exit_system_zone(void);
2195 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2196 ext4_fsblk_t start_blk,
2197 unsigned int count);
2198 extern int ext4_check_blockref(const char *, unsigned int,
2199 struct inode *, __le32 *, unsigned int);
2201 /* extents.c */
2202 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2203 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2204 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2205 int chunk);
2206 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2207 struct ext4_map_blocks *map, int flags);
2208 extern void ext4_ext_truncate(struct inode *);
2209 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2210 loff_t length);
2211 extern void ext4_ext_init(struct super_block *);
2212 extern void ext4_ext_release(struct super_block *);
2213 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2214 loff_t len);
2215 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2216 ssize_t len);
2217 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2218 struct ext4_map_blocks *map, int flags);
2219 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2220 __u64 start, __u64 len);
2221 /* move_extent.c */
2222 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2223 __u64 start_orig, __u64 start_donor,
2224 __u64 len, __u64 *moved_len);
2226 /* page-io.c */
2227 extern int __init ext4_init_pageio(void);
2228 extern void ext4_exit_pageio(void);
2229 extern void ext4_ioend_wait(struct inode *);
2230 extern void ext4_free_io_end(ext4_io_end_t *io);
2231 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2232 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2233 extern void ext4_io_submit(struct ext4_io_submit *io);
2234 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2235 struct page *page,
2236 int len,
2237 struct writeback_control *wbc);
2239 /* mmp.c */
2240 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2242 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2243 enum ext4_state_bits {
2244 BH_Uninit /* blocks are allocated but uninitialized on disk */
2245 = BH_JBDPrivateStart,
2248 BUFFER_FNS(Uninit, uninit)
2249 TAS_BUFFER_FNS(Uninit, uninit)
2252 * Add new method to test wether block and inode bitmaps are properly
2253 * initialized. With uninit_bg reading the block from disk is not enough
2254 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2256 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2258 static inline int bitmap_uptodate(struct buffer_head *bh)
2260 return (buffer_uptodate(bh) &&
2261 test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2263 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2265 set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2268 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2270 /* For ioend & aio unwritten conversion wait queues */
2271 #define EXT4_WQ_HASH_SZ 37
2272 #define ext4_ioend_wq(v) (&ext4__ioend_wq[((unsigned long)(v)) %\
2273 EXT4_WQ_HASH_SZ])
2274 #define ext4_aio_mutex(v) (&ext4__aio_mutex[((unsigned long)(v)) %\
2275 EXT4_WQ_HASH_SZ])
2276 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2277 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2279 #define EXT4_RESIZING 0
2280 extern int ext4_resize_begin(struct super_block *sb);
2281 extern void ext4_resize_end(struct super_block *sb);
2283 #endif /* __KERNEL__ */
2285 #endif /* _EXT4_H */