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TOMOYO Linux Cross Reference
Linux/fs/ext4/ext4.h

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  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/version.h>
 30 #include <linux/wait.h>
 31 #include <linux/blockgroup_lock.h>
 32 #include <linux/percpu_counter.h>
 33 #ifdef __KERNEL__
 34 #include <linux/compat.h>
 35 #endif
 36 
 37 /*
 38  * The fourth extended filesystem constants/structures
 39  */
 40 
 41 /*
 42  * Define EXT4FS_DEBUG to produce debug messages
 43  */
 44 #undef EXT4FS_DEBUG
 45 
 46 /*
 47  * Debug code
 48  */
 49 #ifdef EXT4FS_DEBUG
 50 #define ext4_debug(f, a...)                                             \
 51         do {                                                            \
 52                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
 53                         __FILE__, __LINE__, __func__);                  \
 54                 printk(KERN_DEBUG f, ## a);                             \
 55         } while (0)
 56 #else
 57 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
 58 #endif
 59 
 60 #define EXT4_ERROR_INODE(inode, fmt, a...) \
 61         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
 62 
 63 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
 64         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
 65 
 66 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
 67         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
 68 
 69 /* data type for block offset of block group */
 70 typedef int ext4_grpblk_t;
 71 
 72 /* data type for filesystem-wide blocks number */
 73 typedef unsigned long long ext4_fsblk_t;
 74 
 75 /* data type for file logical block number */
 76 typedef __u32 ext4_lblk_t;
 77 
 78 /* data type for block group number */
 79 typedef unsigned int ext4_group_t;
 80 
 81 /*
 82  * Flags used in mballoc's allocation_context flags field.
 83  *
 84  * Also used to show what's going on for debugging purposes when the
 85  * flag field is exported via the traceport interface
 86  */
 87 
 88 /* prefer goal again. length */
 89 #define EXT4_MB_HINT_MERGE              0x0001
 90 /* blocks already reserved */
 91 #define EXT4_MB_HINT_RESERVED           0x0002
 92 /* metadata is being allocated */
 93 #define EXT4_MB_HINT_METADATA           0x0004
 94 /* first blocks in the file */
 95 #define EXT4_MB_HINT_FIRST              0x0008
 96 /* search for the best chunk */
 97 #define EXT4_MB_HINT_BEST               0x0010
 98 /* data is being allocated */
 99 #define EXT4_MB_HINT_DATA               0x0020
100 /* don't preallocate (for tails) */
101 #define EXT4_MB_HINT_NOPREALLOC         0x0040
102 /* allocate for locality group */
103 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
104 /* allocate goal blocks or none */
105 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
106 /* goal is meaningful */
107 #define EXT4_MB_HINT_TRY_GOAL           0x0200
108 /* blocks already pre-reserved by delayed allocation */
109 #define EXT4_MB_DELALLOC_RESERVED       0x0400
110 /* We are doing stream allocation */
111 #define EXT4_MB_STREAM_ALLOC            0x0800
112 /* Use reserved root blocks if needed */
113 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
114 
115 struct ext4_allocation_request {
116         /* target inode for block we're allocating */
117         struct inode *inode;
118         /* how many blocks we want to allocate */
119         unsigned int len;
120         /* logical block in target inode */
121         ext4_lblk_t logical;
122         /* the closest logical allocated block to the left */
123         ext4_lblk_t lleft;
124         /* the closest logical allocated block to the right */
125         ext4_lblk_t lright;
126         /* phys. target (a hint) */
127         ext4_fsblk_t goal;
128         /* phys. block for the closest logical allocated block to the left */
129         ext4_fsblk_t pleft;
130         /* phys. block for the closest logical allocated block to the right */
131         ext4_fsblk_t pright;
132         /* flags. see above EXT4_MB_HINT_* */
133         unsigned int flags;
134 };
135 
136 /*
137  * Logical to physical block mapping, used by ext4_map_blocks()
138  *
139  * This structure is used to pass requests into ext4_map_blocks() as
140  * well as to store the information returned by ext4_map_blocks().  It
141  * takes less room on the stack than a struct buffer_head.
142  */
143 #define EXT4_MAP_NEW            (1 << BH_New)
144 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
145 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
146 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
147 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
148 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
149  * ext4_map_blocks wants to know whether or not the underlying cluster has
150  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
151  * the requested mapping was from previously mapped (or delayed allocated)
152  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
153  * should never appear on buffer_head's state flags.
154  */
155 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
156 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
157                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
158                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
159 
160 struct ext4_map_blocks {
161         ext4_fsblk_t m_pblk;
162         ext4_lblk_t m_lblk;
163         unsigned int m_len;
164         unsigned int m_flags;
165 };
166 
167 /*
168  * For delayed allocation tracking
169  */
170 struct mpage_da_data {
171         struct inode *inode;
172         sector_t b_blocknr;             /* start block number of extent */
173         size_t b_size;                  /* size of extent */
174         unsigned long b_state;          /* state of the extent */
175         unsigned long first_page, next_page;    /* extent of pages */
176         struct writeback_control *wbc;
177         int io_done;
178         int pages_written;
179         int retval;
180 };
181 
182 /*
183  * Flags for ext4_io_end->flags
184  */
185 #define EXT4_IO_END_UNWRITTEN   0x0001
186 #define EXT4_IO_END_ERROR       0x0002
187 #define EXT4_IO_END_QUEUED      0x0004
188 #define EXT4_IO_END_DIRECT      0x0008
189 #define EXT4_IO_END_IN_FSYNC    0x0010
190 
191 struct ext4_io_page {
192         struct page     *p_page;
193         atomic_t        p_count;
194 };
195 
196 #define MAX_IO_PAGES 128
197 
198 /*
199  * For converting uninitialized extents on a work queue.
200  *
201  * 'page' is only used from the writepage() path; 'pages' is only used for
202  * buffered writes; they are used to keep page references until conversion
203  * takes place.  For AIO/DIO, neither field is filled in.
204  */
205 typedef struct ext4_io_end {
206         struct list_head        list;           /* per-file finished IO list */
207         struct inode            *inode;         /* file being written to */
208         unsigned int            flag;           /* unwritten or not */
209         struct page             *page;          /* for writepage() path */
210         loff_t                  offset;         /* offset in the file */
211         ssize_t                 size;           /* size of the extent */
212         struct work_struct      work;           /* data work queue */
213         struct kiocb            *iocb;          /* iocb struct for AIO */
214         int                     result;         /* error value for AIO */
215         int                     num_io_pages;   /* for writepages() */
216         struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
217 } ext4_io_end_t;
218 
219 struct ext4_io_submit {
220         int                     io_op;
221         struct bio              *io_bio;
222         ext4_io_end_t           *io_end;
223         struct ext4_io_page     *io_page;
224         sector_t                io_next_block;
225 };
226 
227 /*
228  * Special inodes numbers
229  */
230 #define EXT4_BAD_INO             1      /* Bad blocks inode */
231 #define EXT4_ROOT_INO            2      /* Root inode */
232 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
233 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
234 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
235 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
236 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
237 #define EXT4_JOURNAL_INO         8      /* Journal inode */
238 
239 /* First non-reserved inode for old ext4 filesystems */
240 #define EXT4_GOOD_OLD_FIRST_INO 11
241 
242 /*
243  * Maximal count of links to a file
244  */
245 #define EXT4_LINK_MAX           65000
246 
247 /*
248  * Macro-instructions used to manage several block sizes
249  */
250 #define EXT4_MIN_BLOCK_SIZE             1024
251 #define EXT4_MAX_BLOCK_SIZE             65536
252 #define EXT4_MIN_BLOCK_LOG_SIZE         10
253 #define EXT4_MAX_BLOCK_LOG_SIZE         16
254 #ifdef __KERNEL__
255 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
256 #else
257 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
258 #endif
259 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
260 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
261                                          EXT4_SB(s)->s_cluster_bits)
262 #ifdef __KERNEL__
263 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
264 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
265 #else
266 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
267 #endif
268 #ifdef __KERNEL__
269 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
270 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
271 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
272 #else
273 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
274                                  EXT4_GOOD_OLD_INODE_SIZE : \
275                                  (s)->s_inode_size)
276 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
277                                  EXT4_GOOD_OLD_FIRST_INO : \
278                                  (s)->s_first_ino)
279 #endif
280 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
281 
282 /* Translate a block number to a cluster number */
283 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
284 /* Translate a cluster number to a block number */
285 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
286 /* Translate # of blks to # of clusters */
287 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
288                                  (sbi)->s_cluster_bits)
289 
290 /*
291  * Structure of a blocks group descriptor
292  */
293 struct ext4_group_desc
294 {
295         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
296         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
297         __le32  bg_inode_table_lo;      /* Inodes table block */
298         __le16  bg_free_blocks_count_lo;/* Free blocks count */
299         __le16  bg_free_inodes_count_lo;/* Free inodes count */
300         __le16  bg_used_dirs_count_lo;  /* Directories count */
301         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
302         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
303         __le16  bg_itable_unused_lo;    /* Unused inodes count */
304         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
305         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
306         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
307         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
308         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
309         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
310         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
311         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
312         __u32   bg_reserved2[3];
313 };
314 
315 /*
316  * Structure of a flex block group info
317  */
318 
319 struct flex_groups {
320         atomic64_t      free_clusters;
321         atomic_t        free_inodes;
322         atomic_t        used_dirs;
323 };
324 
325 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
326 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
327 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
328 
329 /*
330  * Macro-instructions used to manage group descriptors
331  */
332 #define EXT4_MIN_DESC_SIZE              32
333 #define EXT4_MIN_DESC_SIZE_64BIT        64
334 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
335 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
336 #ifdef __KERNEL__
337 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
338 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
339 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
340 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
341 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
342 #else
343 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
344 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
345 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
346 #endif
347 
348 /*
349  * Constants relative to the data blocks
350  */
351 #define EXT4_NDIR_BLOCKS                12
352 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
353 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
354 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
355 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
356 
357 /*
358  * Inode flags
359  */
360 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
361 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
362 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
363 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
364 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
365 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
366 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
367 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
368 /* Reserved for compression usage... */
369 #define EXT4_DIRTY_FL                   0x00000100
370 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
371 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
372 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
373 /* End compression flags --- maybe not all used */
374 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
375 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
376 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
377 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
378 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
379 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
380 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
381 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
382 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
383 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
384 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
385 
386 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
387 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
388 
389 /* Flags that should be inherited by new inodes from their parent. */
390 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
391                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
392                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
393                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
394 
395 /* Flags that are appropriate for regular files (all but dir-specific ones). */
396 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
397 
398 /* Flags that are appropriate for non-directories/regular files. */
399 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
400 
401 /* Mask out flags that are inappropriate for the given type of inode. */
402 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
403 {
404         if (S_ISDIR(mode))
405                 return flags;
406         else if (S_ISREG(mode))
407                 return flags & EXT4_REG_FLMASK;
408         else
409                 return flags & EXT4_OTHER_FLMASK;
410 }
411 
412 /*
413  * Inode flags used for atomic set/get
414  */
415 enum {
416         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
417         EXT4_INODE_UNRM         = 1,    /* Undelete */
418         EXT4_INODE_COMPR        = 2,    /* Compress file */
419         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
420         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
421         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
422         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
423         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
424 /* Reserved for compression usage... */
425         EXT4_INODE_DIRTY        = 8,
426         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
427         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
428         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
429 /* End compression flags --- maybe not all used */
430         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
431         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
432         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
433         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
434         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
435         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
436         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
437         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
438         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
439         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
440         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
441 };
442 
443 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
444 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
445         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
446                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
447 
448 /*
449  * Since it's pretty easy to mix up bit numbers and hex values, and we
450  * can't do a compile-time test for ENUM values, we use a run-time
451  * test to make sure that EXT4_XXX_FL is consistent with respect to
452  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
453  * out so it won't cost any extra space in the compiled kernel image.
454  * But it's important that these values are the same, since we are
455  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
456  * must be consistent with the values of FS_XXX_FL defined in
457  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
458  * ext4 filesystems, and of course the values defined in e2fsprogs.
459  *
460  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
461  */
462 static inline void ext4_check_flag_values(void)
463 {
464         CHECK_FLAG_VALUE(SECRM);
465         CHECK_FLAG_VALUE(UNRM);
466         CHECK_FLAG_VALUE(COMPR);
467         CHECK_FLAG_VALUE(SYNC);
468         CHECK_FLAG_VALUE(IMMUTABLE);
469         CHECK_FLAG_VALUE(APPEND);
470         CHECK_FLAG_VALUE(NODUMP);
471         CHECK_FLAG_VALUE(NOATIME);
472         CHECK_FLAG_VALUE(DIRTY);
473         CHECK_FLAG_VALUE(COMPRBLK);
474         CHECK_FLAG_VALUE(NOCOMPR);
475         CHECK_FLAG_VALUE(ECOMPR);
476         CHECK_FLAG_VALUE(INDEX);
477         CHECK_FLAG_VALUE(IMAGIC);
478         CHECK_FLAG_VALUE(JOURNAL_DATA);
479         CHECK_FLAG_VALUE(NOTAIL);
480         CHECK_FLAG_VALUE(DIRSYNC);
481         CHECK_FLAG_VALUE(TOPDIR);
482         CHECK_FLAG_VALUE(HUGE_FILE);
483         CHECK_FLAG_VALUE(EXTENTS);
484         CHECK_FLAG_VALUE(EA_INODE);
485         CHECK_FLAG_VALUE(EOFBLOCKS);
486         CHECK_FLAG_VALUE(RESERVED);
487 }
488 
489 /* Used to pass group descriptor data when online resize is done */
490 struct ext4_new_group_input {
491         __u32 group;            /* Group number for this data */
492         __u64 block_bitmap;     /* Absolute block number of block bitmap */
493         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
494         __u64 inode_table;      /* Absolute block number of inode table start */
495         __u32 blocks_count;     /* Total number of blocks in this group */
496         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
497         __u16 unused;
498 };
499 
500 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
501 struct compat_ext4_new_group_input {
502         u32 group;
503         compat_u64 block_bitmap;
504         compat_u64 inode_bitmap;
505         compat_u64 inode_table;
506         u32 blocks_count;
507         u16 reserved_blocks;
508         u16 unused;
509 };
510 #endif
511 
512 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
513 struct ext4_new_group_data {
514         __u32 group;
515         __u64 block_bitmap;
516         __u64 inode_bitmap;
517         __u64 inode_table;
518         __u32 blocks_count;
519         __u16 reserved_blocks;
520         __u16 unused;
521         __u32 free_blocks_count;
522 };
523 
524 /* Indexes used to index group tables in ext4_new_group_data */
525 enum {
526         BLOCK_BITMAP = 0,       /* block bitmap */
527         INODE_BITMAP,           /* inode bitmap */
528         INODE_TABLE,            /* inode tables */
529         GROUP_TABLE_COUNT,
530 };
531 
532 /*
533  * Flags used by ext4_map_blocks()
534  */
535         /* Allocate any needed blocks and/or convert an unitialized
536            extent to be an initialized ext4 */
537 #define EXT4_GET_BLOCKS_CREATE                  0x0001
538         /* Request the creation of an unitialized extent */
539 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
540 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
541                                                  EXT4_GET_BLOCKS_CREATE)
542         /* Caller is from the delayed allocation writeout path,
543            so set the magic i_delalloc_reserve_flag after taking the
544            inode allocation semaphore for */
545 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
546         /* caller is from the direct IO path, request to creation of an
547         unitialized extents if not allocated, split the uninitialized
548         extent if blocks has been preallocated already*/
549 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
550 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
551 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
552                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
553         /* Convert extent to initialized after IO complete */
554 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
555                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
556         /* Punch out blocks of an extent */
557 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
558         /* Don't normalize allocation size (used for fallocate) */
559 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
560         /* Request will not result in inode size update (user for fallocate) */
561 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
562 
563 /*
564  * Flags used by ext4_free_blocks
565  */
566 #define EXT4_FREE_BLOCKS_METADATA       0x0001
567 #define EXT4_FREE_BLOCKS_FORGET         0x0002
568 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
569 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
570 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
571 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
572 
573 /*
574  * Flags used by ext4_discard_partial_page_buffers
575  */
576 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
577 
578 /*
579  * ioctl commands
580  */
581 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
582 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
583 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
584 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
585 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
586 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
587 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
588 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
589 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
590 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
591 #define EXT4_IOC_MIGRATE                _IO('f', 9)
592  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
593  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
594 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
595 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
596 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
597 
598 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
599 /*
600  * ioctl commands in 32 bit emulation
601  */
602 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
603 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
604 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
605 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
606 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
607 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
608 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
609 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
610 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
611 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
612 #endif
613 
614 /* Max physical block we can address w/o extents */
615 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
616 
617 /*
618  * Structure of an inode on the disk
619  */
620 struct ext4_inode {
621         __le16  i_mode;         /* File mode */
622         __le16  i_uid;          /* Low 16 bits of Owner Uid */
623         __le32  i_size_lo;      /* Size in bytes */
624         __le32  i_atime;        /* Access time */
625         __le32  i_ctime;        /* Inode Change time */
626         __le32  i_mtime;        /* Modification time */
627         __le32  i_dtime;        /* Deletion Time */
628         __le16  i_gid;          /* Low 16 bits of Group Id */
629         __le16  i_links_count;  /* Links count */
630         __le32  i_blocks_lo;    /* Blocks count */
631         __le32  i_flags;        /* File flags */
632         union {
633                 struct {
634                         __le32  l_i_version;
635                 } linux1;
636                 struct {
637                         __u32  h_i_translator;
638                 } hurd1;
639                 struct {
640                         __u32  m_i_reserved1;
641                 } masix1;
642         } osd1;                         /* OS dependent 1 */
643         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
644         __le32  i_generation;   /* File version (for NFS) */
645         __le32  i_file_acl_lo;  /* File ACL */
646         __le32  i_size_high;
647         __le32  i_obso_faddr;   /* Obsoleted fragment address */
648         union {
649                 struct {
650                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
651                         __le16  l_i_file_acl_high;
652                         __le16  l_i_uid_high;   /* these 2 fields */
653                         __le16  l_i_gid_high;   /* were reserved2[0] */
654                         __u32   l_i_reserved2;
655                 } linux2;
656                 struct {
657                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
658                         __u16   h_i_mode_high;
659                         __u16   h_i_uid_high;
660                         __u16   h_i_gid_high;
661                         __u32   h_i_author;
662                 } hurd2;
663                 struct {
664                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
665                         __le16  m_i_file_acl_high;
666                         __u32   m_i_reserved2[2];
667                 } masix2;
668         } osd2;                         /* OS dependent 2 */
669         __le16  i_extra_isize;
670         __le16  i_pad1;
671         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
672         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
673         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
674         __le32  i_crtime;       /* File Creation time */
675         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
676         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
677 };
678 
679 struct move_extent {
680         __u32 reserved;         /* should be zero */
681         __u32 donor_fd;         /* donor file descriptor */
682         __u64 orig_start;       /* logical start offset in block for orig */
683         __u64 donor_start;      /* logical start offset in block for donor */
684         __u64 len;              /* block length to be moved */
685         __u64 moved_len;        /* moved block length */
686 };
687 
688 #define EXT4_EPOCH_BITS 2
689 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
690 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
691 
692 /*
693  * Extended fields will fit into an inode if the filesystem was formatted
694  * with large inodes (-I 256 or larger) and there are not currently any EAs
695  * consuming all of the available space. For new inodes we always reserve
696  * enough space for the kernel's known extended fields, but for inodes
697  * created with an old kernel this might not have been the case. None of
698  * the extended inode fields is critical for correct filesystem operation.
699  * This macro checks if a certain field fits in the inode. Note that
700  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
701  */
702 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
703         ((offsetof(typeof(*ext4_inode), field) +        \
704           sizeof((ext4_inode)->field))                  \
705         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
706             (einode)->i_extra_isize))                   \
707 
708 /*
709  * We use an encoding that preserves the times for extra epoch "00":
710  *
711  * extra  msb of                         adjust for signed
712  * epoch  32-bit                         32-bit tv_sec to
713  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
714  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
715  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
716  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
717  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
718  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
719  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
720  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
721  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
722  *
723  * Note that previous versions of the kernel on 64-bit systems would
724  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
725  * 1970.  e2fsck will correct this, assuming that it is run on the
726  * affected filesystem before 2242.
727  */
728 
729 static inline __le32 ext4_encode_extra_time(struct timespec *time)
730 {
731         u32 extra = sizeof(time->tv_sec) > 4 ?
732                 ((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
733         return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
734 }
735 
736 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
737 {
738         if (unlikely(sizeof(time->tv_sec) > 4 &&
739                         (extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
740 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,20,0)
741                 /* Handle legacy encoding of pre-1970 dates with epoch
742                  * bits 1,1.  We assume that by kernel version 4.20,
743                  * everyone will have run fsck over the affected
744                  * filesystems to correct the problem.  (This
745                  * backwards compatibility may be removed before this
746                  * time, at the discretion of the ext4 developers.)
747                  */
748                 u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
749                 if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
750                         extra_bits = 0;
751                 time->tv_sec += extra_bits << 32;
752 #else
753                 time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
754 #endif
755         }
756         time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
757 }
758 
759 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
760 do {                                                                           \
761         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
762         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
763                 (raw_inode)->xtime ## _extra =                                 \
764                                 ext4_encode_extra_time(&(inode)->xtime);       \
765 } while (0)
766 
767 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
768 do {                                                                           \
769         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
770                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
771         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
772                 (raw_inode)->xtime ## _extra =                                 \
773                                 ext4_encode_extra_time(&(einode)->xtime);      \
774 } while (0)
775 
776 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
777 do {                                                                           \
778         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
779         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
780                 ext4_decode_extra_time(&(inode)->xtime,                        \
781                                        raw_inode->xtime ## _extra);            \
782         else                                                                   \
783                 (inode)->xtime.tv_nsec = 0;                                    \
784 } while (0)
785 
786 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
787 do {                                                                           \
788         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
789                 (einode)->xtime.tv_sec =                                       \
790                         (signed)le32_to_cpu((raw_inode)->xtime);               \
791         else                                                                   \
792                 (einode)->xtime.tv_sec = 0;                                    \
793         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
794                 ext4_decode_extra_time(&(einode)->xtime,                       \
795                                        raw_inode->xtime ## _extra);            \
796         else                                                                   \
797                 (einode)->xtime.tv_nsec = 0;                                   \
798 } while (0)
799 
800 #define i_disk_version osd1.linux1.l_i_version
801 
802 #if defined(__KERNEL__) || defined(__linux__)
803 #define i_reserved1     osd1.linux1.l_i_reserved1
804 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
805 #define i_blocks_high   osd2.linux2.l_i_blocks_high
806 #define i_uid_low       i_uid
807 #define i_gid_low       i_gid
808 #define i_uid_high      osd2.linux2.l_i_uid_high
809 #define i_gid_high      osd2.linux2.l_i_gid_high
810 #define i_reserved2     osd2.linux2.l_i_reserved2
811 
812 #elif defined(__GNU__)
813 
814 #define i_translator    osd1.hurd1.h_i_translator
815 #define i_uid_high      osd2.hurd2.h_i_uid_high
816 #define i_gid_high      osd2.hurd2.h_i_gid_high
817 #define i_author        osd2.hurd2.h_i_author
818 
819 #elif defined(__masix__)
820 
821 #define i_reserved1     osd1.masix1.m_i_reserved1
822 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
823 #define i_reserved2     osd2.masix2.m_i_reserved2
824 
825 #endif /* defined(__KERNEL__) || defined(__linux__) */
826 
827 /*
828  * storage for cached extent
829  * If ec_len == 0, then the cache is invalid.
830  * If ec_start == 0, then the cache represents a gap (null mapping)
831  */
832 struct ext4_ext_cache {
833         ext4_fsblk_t    ec_start;
834         ext4_lblk_t     ec_block;
835         __u32           ec_len; /* must be 32bit to return holes */
836 };
837 
838 /*
839  * fourth extended file system inode data in memory
840  */
841 struct ext4_inode_info {
842         __le32  i_data[15];     /* unconverted */
843         __u32   i_dtime;
844         ext4_fsblk_t    i_file_acl;
845 
846         /*
847          * i_block_group is the number of the block group which contains
848          * this file's inode.  Constant across the lifetime of the inode,
849          * it is ued for making block allocation decisions - we try to
850          * place a file's data blocks near its inode block, and new inodes
851          * near to their parent directory's inode.
852          */
853         ext4_group_t    i_block_group;
854         ext4_lblk_t     i_dir_start_lookup;
855 #if (BITS_PER_LONG < 64)
856         unsigned long   i_state_flags;          /* Dynamic state flags */
857 #endif
858         unsigned long   i_flags;
859 
860 #ifdef CONFIG_EXT4_FS_XATTR
861         /*
862          * Extended attributes can be read independently of the main file
863          * data. Taking i_mutex even when reading would cause contention
864          * between readers of EAs and writers of regular file data, so
865          * instead we synchronize on xattr_sem when reading or changing
866          * EAs.
867          */
868         struct rw_semaphore xattr_sem;
869 #endif
870 
871         struct list_head i_orphan;      /* unlinked but open inodes */
872 
873         /*
874          * i_disksize keeps track of what the inode size is ON DISK, not
875          * in memory.  During truncate, i_size is set to the new size by
876          * the VFS prior to calling ext4_truncate(), but the filesystem won't
877          * set i_disksize to 0 until the truncate is actually under way.
878          *
879          * The intent is that i_disksize always represents the blocks which
880          * are used by this file.  This allows recovery to restart truncate
881          * on orphans if we crash during truncate.  We actually write i_disksize
882          * into the on-disk inode when writing inodes out, instead of i_size.
883          *
884          * The only time when i_disksize and i_size may be different is when
885          * a truncate is in progress.  The only things which change i_disksize
886          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
887          */
888         loff_t  i_disksize;
889 
890         /*
891          * i_data_sem is for serialising ext4_truncate() against
892          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
893          * data tree are chopped off during truncate. We can't do that in
894          * ext4 because whenever we perform intermediate commits during
895          * truncate, the inode and all the metadata blocks *must* be in a
896          * consistent state which allows truncation of the orphans to restart
897          * during recovery.  Hence we must fix the get_block-vs-truncate race
898          * by other means, so we have i_data_sem.
899          */
900         struct rw_semaphore i_data_sem;
901         struct inode vfs_inode;
902         struct jbd2_inode *jinode;
903 
904         struct ext4_ext_cache i_cached_extent;
905         /*
906          * File creation time. Its function is same as that of
907          * struct timespec i_{a,c,m}time in the generic inode.
908          */
909         struct timespec i_crtime;
910 
911         /* mballoc */
912         struct list_head i_prealloc_list;
913         spinlock_t i_prealloc_lock;
914 
915         /* ialloc */
916         ext4_group_t    i_last_alloc_group;
917 
918         /* allocation reservation info for delalloc */
919         /* In case of bigalloc, these refer to clusters rather than blocks */
920         unsigned int i_reserved_data_blocks;
921         unsigned int i_reserved_meta_blocks;
922         unsigned int i_allocated_meta_blocks;
923         ext4_lblk_t i_da_metadata_calc_last_lblock;
924         int i_da_metadata_calc_len;
925 
926         /* on-disk additional length */
927         __u16 i_extra_isize;
928 
929 #ifdef CONFIG_QUOTA
930         /* quota space reservation, managed internally by quota code */
931         qsize_t i_reserved_quota;
932 #endif
933 
934         /* completed IOs that might need unwritten extents handling */
935         struct list_head i_completed_io_list;
936         spinlock_t i_completed_io_lock;
937         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
938         /* current io_end structure for async DIO write*/
939         ext4_io_end_t *cur_aio_dio;
940         atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
941 
942         spinlock_t i_block_reservation_lock;
943 
944         /*
945          * Transactions that contain inode's metadata needed to complete
946          * fsync and fdatasync, respectively.
947          */
948         tid_t i_sync_tid;
949         tid_t i_datasync_tid;
950 };
951 
952 /*
953  * File system states
954  */
955 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
956 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
957 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
958 
959 /*
960  * Misc. filesystem flags
961  */
962 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
963 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
964 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
965 
966 /*
967  * Mount flags
968  */
969 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
970 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
971 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
972 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
973 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
974 #define EXT4_MOUNT_ERRORS_MASK          0x00070
975 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
976 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
977 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
978 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
979 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
980 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
981 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
982 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
983 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
984 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
985 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
986 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
987 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
988 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
989 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
990 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
991 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
992 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
993 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
994 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
995 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
996 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
997 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
998 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
999 
1000 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1001                                                       specified delalloc */
1002 
1003 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1004                                                 ~EXT4_MOUNT_##opt
1005 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1006                                                 EXT4_MOUNT_##opt
1007 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1008                                          EXT4_MOUNT_##opt)
1009 
1010 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1011                                                 ~EXT4_MOUNT2_##opt
1012 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1013                                                 EXT4_MOUNT2_##opt
1014 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1015                                          EXT4_MOUNT2_##opt)
1016 
1017 #define ext4_test_and_set_bit           __test_and_set_bit_le
1018 #define ext4_set_bit                    __set_bit_le
1019 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1020 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1021 #define ext4_clear_bit                  __clear_bit_le
1022 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1023 #define ext4_test_bit                   test_bit_le
1024 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1025 #define ext4_find_next_bit              find_next_bit_le
1026 
1027 extern void ext4_set_bits(void *bm, int cur, int len);
1028 
1029 /*
1030  * Maximal mount counts between two filesystem checks
1031  */
1032 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1033 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1034 
1035 /*
1036  * Behaviour when detecting errors
1037  */
1038 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1039 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1040 #define EXT4_ERRORS_PANIC               3       /* Panic */
1041 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1042 
1043 /*
1044  * Structure of the super block
1045  */
1046 struct ext4_super_block {
1047 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1048         __le32  s_blocks_count_lo;      /* Blocks count */
1049         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1050         __le32  s_free_blocks_count_lo; /* Free blocks count */
1051 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1052         __le32  s_first_data_block;     /* First Data Block */
1053         __le32  s_log_block_size;       /* Block size */
1054         __le32  s_log_cluster_size;     /* Allocation cluster size */
1055 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1056         __le32  s_clusters_per_group;   /* # Clusters per group */
1057         __le32  s_inodes_per_group;     /* # Inodes per group */
1058         __le32  s_mtime;                /* Mount time */
1059 /*30*/  __le32  s_wtime;                /* Write time */
1060         __le16  s_mnt_count;            /* Mount count */
1061         __le16  s_max_mnt_count;        /* Maximal mount count */
1062         __le16  s_magic;                /* Magic signature */
1063         __le16  s_state;                /* File system state */
1064         __le16  s_errors;               /* Behaviour when detecting errors */
1065         __le16  s_minor_rev_level;      /* minor revision level */
1066 /*40*/  __le32  s_lastcheck;            /* time of last check */
1067         __le32  s_checkinterval;        /* max. time between checks */
1068         __le32  s_creator_os;           /* OS */
1069         __le32  s_rev_level;            /* Revision level */
1070 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1071         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1072         /*
1073          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1074          *
1075          * Note: the difference between the compatible feature set and
1076          * the incompatible feature set is that if there is a bit set
1077          * in the incompatible feature set that the kernel doesn't
1078          * know about, it should refuse to mount the filesystem.
1079          *
1080          * e2fsck's requirements are more strict; if it doesn't know
1081          * about a feature in either the compatible or incompatible
1082          * feature set, it must abort and not try to meddle with
1083          * things it doesn't understand...
1084          */
1085         __le32  s_first_ino;            /* First non-reserved inode */
1086         __le16  s_inode_size;           /* size of inode structure */
1087         __le16  s_block_group_nr;       /* block group # of this superblock */
1088         __le32  s_feature_compat;       /* compatible feature set */
1089 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1090         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1091 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1092 /*78*/  char    s_volume_name[16];      /* volume name */
1093 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1094 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1095         /*
1096          * Performance hints.  Directory preallocation should only
1097          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1098          */
1099         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1100         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1101         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1102         /*
1103          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1104          */
1105 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1106 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1107         __le32  s_journal_dev;          /* device number of journal file */
1108         __le32  s_last_orphan;          /* start of list of inodes to delete */
1109         __le32  s_hash_seed[4];         /* HTREE hash seed */
1110         __u8    s_def_hash_version;     /* Default hash version to use */
1111         __u8    s_jnl_backup_type;
1112         __le16  s_desc_size;            /* size of group descriptor */
1113 /*100*/ __le32  s_default_mount_opts;
1114         __le32  s_first_meta_bg;        /* First metablock block group */
1115         __le32  s_mkfs_time;            /* When the filesystem was created */
1116         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1117         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1118 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1119         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1120         __le32  s_free_blocks_count_hi; /* Free blocks count */
1121         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1122         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1123         __le32  s_flags;                /* Miscellaneous flags */
1124         __le16  s_raid_stride;          /* RAID stride */
1125         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1126         __le64  s_mmp_block;            /* Block for multi-mount protection */
1127         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1128         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1129         __u8    s_reserved_char_pad;
1130         __le16  s_reserved_pad;
1131         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1132         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1133         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1134         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1135                                               snapshot's future use */
1136         __le32  s_snapshot_list;        /* inode number of the head of the
1137                                            on-disk snapshot list */
1138 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1139         __le32  s_error_count;          /* number of fs errors */
1140         __le32  s_first_error_time;     /* first time an error happened */
1141         __le32  s_first_error_ino;      /* inode involved in first error */
1142         __le64  s_first_error_block;    /* block involved of first error */
1143         __u8    s_first_error_func[32]; /* function where the error happened */
1144         __le32  s_first_error_line;     /* line number where error happened */
1145         __le32  s_last_error_time;      /* most recent time of an error */
1146         __le32  s_last_error_ino;       /* inode involved in last error */
1147         __le32  s_last_error_line;      /* line number where error happened */
1148         __le64  s_last_error_block;     /* block involved of last error */
1149         __u8    s_last_error_func[32];  /* function where the error happened */
1150 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1151         __u8    s_mount_opts[64];
1152         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1153         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1154         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1155         __le32  s_reserved[109];        /* Padding to the end of the block */
1156 };
1157 
1158 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1159 
1160 #ifdef __KERNEL__
1161 
1162 /*
1163  * run-time mount flags
1164  */
1165 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1166 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1167 
1168 /*
1169  * fourth extended-fs super-block data in memory
1170  */
1171 struct ext4_sb_info {
1172         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1173         unsigned long s_inodes_per_block;/* Number of inodes per block */
1174         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1175         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1176         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1177         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1178         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1179         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1180         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1181         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1182         unsigned long s_overhead;  /* # of fs overhead clusters */
1183         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1184         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1185         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1186         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1187         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1188         struct buffer_head **s_group_desc;
1189         unsigned int s_mount_opt;
1190         unsigned int s_mount_opt2;
1191         unsigned int s_mount_flags;
1192         unsigned int s_def_mount_opt;
1193         ext4_fsblk_t s_sb_block;
1194         uid_t s_resuid;
1195         gid_t s_resgid;
1196         unsigned short s_mount_state;
1197         unsigned short s_pad;
1198         int s_addr_per_block_bits;
1199         int s_desc_per_block_bits;
1200         int s_inode_size;
1201         int s_first_ino;
1202         unsigned int s_inode_readahead_blks;
1203         unsigned int s_inode_goal;
1204         spinlock_t s_next_gen_lock;
1205         u32 s_next_generation;
1206         u32 s_hash_seed[4];
1207         int s_def_hash_version;
1208         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1209         struct percpu_counter s_freeclusters_counter;
1210         struct percpu_counter s_freeinodes_counter;
1211         struct percpu_counter s_dirs_counter;
1212         struct percpu_counter s_dirtyclusters_counter;
1213         struct blockgroup_lock *s_blockgroup_lock;
1214         struct proc_dir_entry *s_proc;
1215         struct kobject s_kobj;
1216         struct completion s_kobj_unregister;
1217 
1218         /* Journaling */
1219         struct journal_s *s_journal;
1220         struct list_head s_orphan;
1221         struct mutex s_orphan_lock;
1222         unsigned long s_resize_flags;           /* Flags indicating if there
1223                                                    is a resizer */
1224         unsigned long s_commit_interval;
1225         u32 s_max_batch_time;
1226         u32 s_min_batch_time;
1227         struct block_device *journal_bdev;
1228 #ifdef CONFIG_QUOTA
1229         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1230         int s_jquota_fmt;                       /* Format of quota to use */
1231 #endif
1232         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1233         struct rb_root system_blks;
1234 
1235 #ifdef EXTENTS_STATS
1236         /* ext4 extents stats */
1237         unsigned long s_ext_min;
1238         unsigned long s_ext_max;
1239         unsigned long s_depth_max;
1240         spinlock_t s_ext_stats_lock;
1241         unsigned long s_ext_blocks;
1242         unsigned long s_ext_extents;
1243 #endif
1244 
1245         /* for buddy allocator */
1246         struct ext4_group_info ***s_group_info;
1247         struct inode *s_buddy_cache;
1248         spinlock_t s_md_lock;
1249         unsigned short *s_mb_offsets;
1250         unsigned int *s_mb_maxs;
1251 
1252         /* tunables */
1253         unsigned long s_stripe;
1254         unsigned int s_mb_stream_request;
1255         unsigned int s_mb_max_to_scan;
1256         unsigned int s_mb_min_to_scan;
1257         unsigned int s_mb_stats;
1258         unsigned int s_mb_order2_reqs;
1259         unsigned int s_mb_group_prealloc;
1260         unsigned int s_max_writeback_mb_bump;
1261         /* where last allocation was done - for stream allocation */
1262         unsigned long s_mb_last_group;
1263         unsigned long s_mb_last_start;
1264 
1265         /* stats for buddy allocator */
1266         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1267         atomic_t s_bal_success; /* we found long enough chunks */
1268         atomic_t s_bal_allocated;       /* in blocks */
1269         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1270         atomic_t s_bal_goals;   /* goal hits */
1271         atomic_t s_bal_breaks;  /* too long searches */
1272         atomic_t s_bal_2orders; /* 2^order hits */
1273         spinlock_t s_bal_lock;
1274         unsigned long s_mb_buddies_generated;
1275         unsigned long long s_mb_generation_time;
1276         atomic_t s_mb_lost_chunks;
1277         atomic_t s_mb_preallocated;
1278         atomic_t s_mb_discarded;
1279         atomic_t s_lock_busy;
1280 
1281         /* locality groups */
1282         struct ext4_locality_group __percpu *s_locality_groups;
1283 
1284         /* for write statistics */
1285         unsigned long s_sectors_written_start;
1286         u64 s_kbytes_written;
1287 
1288         unsigned int s_log_groups_per_flex;
1289         struct flex_groups *s_flex_groups;
1290 
1291         /* workqueue for dio unwritten */
1292         struct workqueue_struct *dio_unwritten_wq;
1293 
1294         /* timer for periodic error stats printing */
1295         struct timer_list s_err_report;
1296 
1297         /* Lazy inode table initialization info */
1298         struct ext4_li_request *s_li_request;
1299         /* Wait multiplier for lazy initialization thread */
1300         unsigned int s_li_wait_mult;
1301 
1302         /* Kernel thread for multiple mount protection */
1303         struct task_struct *s_mmp_tsk;
1304 
1305         /* record the last minlen when FITRIM is called. */
1306         atomic_t s_last_trim_minblks;
1307 };
1308 
1309 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1310 {
1311         return sb->s_fs_info;
1312 }
1313 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1314 {
1315         return container_of(inode, struct ext4_inode_info, vfs_inode);
1316 }
1317 
1318 static inline struct timespec ext4_current_time(struct inode *inode)
1319 {
1320         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1321                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1322 }
1323 
1324 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1325 {
1326         return ino == EXT4_ROOT_INO ||
1327                 ino == EXT4_JOURNAL_INO ||
1328                 ino == EXT4_RESIZE_INO ||
1329                 (ino >= EXT4_FIRST_INO(sb) &&
1330                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1331 }
1332 
1333 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1334                                               struct ext4_io_end *io_end)
1335 {
1336         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1337                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1338                 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
1339         }
1340 }
1341 
1342 /*
1343  * Inode dynamic state flags
1344  */
1345 enum {
1346         EXT4_STATE_JDATA,               /* journaled data exists */
1347         EXT4_STATE_NEW,                 /* inode is newly created */
1348         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1349         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1350         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1351         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1352         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1353         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1354         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1355 };
1356 
1357 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1358 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1359 {                                                                       \
1360         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1361 }                                                                       \
1362 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1363 {                                                                       \
1364         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1365 }                                                                       \
1366 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1367 {                                                                       \
1368         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1369 }
1370 
1371 EXT4_INODE_BIT_FNS(flag, flags, 0)
1372 #if (BITS_PER_LONG < 64)
1373 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1374 
1375 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1376 {
1377         (ei)->i_state_flags = 0;
1378 }
1379 #else
1380 EXT4_INODE_BIT_FNS(state, flags, 32)
1381 
1382 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1383 {
1384         /* We depend on the fact that callers will set i_flags */
1385 }
1386 #endif
1387 #else
1388 /* Assume that user mode programs are passing in an ext4fs superblock, not
1389  * a kernel struct super_block.  This will allow us to call the feature-test
1390  * macros from user land. */
1391 #define EXT4_SB(sb)     (sb)
1392 #endif
1393 
1394 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1395 
1396 /*
1397  * Codes for operating systems
1398  */
1399 #define EXT4_OS_LINUX           0
1400 #define EXT4_OS_HURD            1
1401 #define EXT4_OS_MASIX           2
1402 #define EXT4_OS_FREEBSD         3
1403 #define EXT4_OS_LITES           4
1404 
1405 /*
1406  * Revision levels
1407  */
1408 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1409 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1410 
1411 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1412 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1413 
1414 #define EXT4_GOOD_OLD_INODE_SIZE 128
1415 
1416 /*
1417  * Feature set definitions
1418  */
1419 
1420 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1421         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1422 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1423         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1424 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1425         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1426 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1427         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1428 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1429         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1430 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1431         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1432 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1433         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1434 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1435         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1436 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1437         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1438 
1439 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1440 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1441 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1442 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1443 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1444 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1445 
1446 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1447 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1448 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1449 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1450 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1451 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1452 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1453 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1454 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1455 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1456 
1457 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1458 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1459 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1460 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1461 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1462 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1463 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1464 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1465 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1466 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1467 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1468 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1469 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1470 #define EXT4_FEATURE_INCOMPAT_INLINEDATA        0x8000 /* data in inode */
1471 
1472 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1473 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1474                                          EXT4_FEATURE_INCOMPAT_META_BG)
1475 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1476                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1477                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1478 
1479 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1480 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1481                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1482                                          EXT4_FEATURE_INCOMPAT_META_BG)
1483 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1484                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1485                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1486 
1487 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1488 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1489                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1490                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1491                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1492                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1493                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1494                                          EXT4_FEATURE_INCOMPAT_MMP)
1495 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1496                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1497                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1498                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1499                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1500                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1501                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1502                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC)
1503 
1504 /*
1505  * Default values for user and/or group using reserved blocks
1506  */
1507 #define EXT4_DEF_RESUID         0
1508 #define EXT4_DEF_RESGID         0
1509 
1510 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1511 
1512 /*
1513  * Default mount options
1514  */
1515 #define EXT4_DEFM_DEBUG         0x0001
1516 #define EXT4_DEFM_BSDGROUPS     0x0002
1517 #define EXT4_DEFM_XATTR_USER    0x0004
1518 #define EXT4_DEFM_ACL           0x0008
1519 #define EXT4_DEFM_UID16         0x0010
1520 #define EXT4_DEFM_JMODE         0x0060
1521 #define EXT4_DEFM_JMODE_DATA    0x0020
1522 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1523 #define EXT4_DEFM_JMODE_WBACK   0x0060
1524 #define EXT4_DEFM_NOBARRIER     0x0100
1525 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1526 #define EXT4_DEFM_DISCARD       0x0400
1527 #define EXT4_DEFM_NODELALLOC    0x0800
1528 
1529 /*
1530  * Default journal batch times
1531  */
1532 #define EXT4_DEF_MIN_BATCH_TIME 0
1533 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1534 
1535 /*
1536  * Minimum number of groups in a flexgroup before we separate out
1537  * directories into the first block group of a flexgroup
1538  */
1539 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1540 
1541 /*
1542  * Structure of a directory entry
1543  */
1544 #define EXT4_NAME_LEN 255
1545 
1546 struct ext4_dir_entry {
1547         __le32  inode;                  /* Inode number */
1548         __le16  rec_len;                /* Directory entry length */
1549         __le16  name_len;               /* Name length */
1550         char    name[EXT4_NAME_LEN];    /* File name */
1551 };
1552 
1553 /*
1554  * The new version of the directory entry.  Since EXT4 structures are
1555  * stored in intel byte order, and the name_len field could never be
1556  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1557  * file_type field.
1558  */
1559 struct ext4_dir_entry_2 {
1560         __le32  inode;                  /* Inode number */
1561         __le16  rec_len;                /* Directory entry length */
1562         __u8    name_len;               /* Name length */
1563         __u8    file_type;
1564         char    name[EXT4_NAME_LEN];    /* File name */
1565 };
1566 
1567 /*
1568  * Ext4 directory file types.  Only the low 3 bits are used.  The
1569  * other bits are reserved for now.
1570  */
1571 #define EXT4_FT_UNKNOWN         0
1572 #define EXT4_FT_REG_FILE        1
1573 #define EXT4_FT_DIR             2
1574 #define EXT4_FT_CHRDEV          3
1575 #define EXT4_FT_BLKDEV          4
1576 #define EXT4_FT_FIFO            5
1577 #define EXT4_FT_SOCK            6
1578 #define EXT4_FT_SYMLINK         7
1579 
1580 #define EXT4_FT_MAX             8
1581 
1582 /*
1583  * EXT4_DIR_PAD defines the directory entries boundaries
1584  *
1585  * NOTE: It must be a multiple of 4
1586  */
1587 #define EXT4_DIR_PAD                    4
1588 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1589 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1590                                          ~EXT4_DIR_ROUND)
1591 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1592 
1593 /*
1594  * If we ever get support for fs block sizes > page_size, we'll need
1595  * to remove the #if statements in the next two functions...
1596  */
1597 static inline unsigned int
1598 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1599 {
1600         unsigned len = le16_to_cpu(dlen);
1601 
1602 #if (PAGE_CACHE_SIZE >= 65536)
1603         if (len == EXT4_MAX_REC_LEN || len == 0)
1604                 return blocksize;
1605         return (len & 65532) | ((len & 3) << 16);
1606 #else
1607         return len;
1608 #endif
1609 }
1610 
1611 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1612 {
1613         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1614                 BUG();
1615 #if (PAGE_CACHE_SIZE >= 65536)
1616         if (len < 65536)
1617                 return cpu_to_le16(len);
1618         if (len == blocksize) {
1619                 if (blocksize == 65536)
1620                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1621                 else
1622                         return cpu_to_le16(0);
1623         }
1624         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1625 #else
1626         return cpu_to_le16(len);
1627 #endif
1628 }
1629 
1630 /*
1631  * Hash Tree Directory indexing
1632  * (c) Daniel Phillips, 2001
1633  */
1634 
1635 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1636                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1637                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1638 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1639 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1640 
1641 /* Legal values for the dx_root hash_version field: */
1642 
1643 #define DX_HASH_LEGACY          0
1644 #define DX_HASH_HALF_MD4        1
1645 #define DX_HASH_TEA             2
1646 #define DX_HASH_LEGACY_UNSIGNED 3
1647 #define DX_HASH_HALF_MD4_UNSIGNED       4
1648 #define DX_HASH_TEA_UNSIGNED            5
1649 
1650 #ifdef __KERNEL__
1651 
1652 /* hash info structure used by the directory hash */
1653 struct dx_hash_info
1654 {
1655         u32             hash;
1656         u32             minor_hash;
1657         int             hash_version;
1658         u32             *seed;
1659 };
1660 
1661 
1662 /* 32 and 64 bit signed EOF for dx directories */
1663 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1664 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1665 
1666 
1667 /*
1668  * Control parameters used by ext4_htree_next_block
1669  */
1670 #define HASH_NB_ALWAYS          1
1671 
1672 
1673 /*
1674  * Describe an inode's exact location on disk and in memory
1675  */
1676 struct ext4_iloc
1677 {
1678         struct buffer_head *bh;
1679         unsigned long offset;
1680         ext4_group_t block_group;
1681 };
1682 
1683 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1684 {
1685         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1686 }
1687 
1688 /*
1689  * This structure is stuffed into the struct file's private_data field
1690  * for directories.  It is where we put information so that we can do
1691  * readdir operations in hash tree order.
1692  */
1693 struct dir_private_info {
1694         struct rb_root  root;
1695         struct rb_node  *curr_node;
1696         struct fname    *extra_fname;
1697         loff_t          last_pos;
1698         __u32           curr_hash;
1699         __u32           curr_minor_hash;
1700         __u32           next_hash;
1701 };
1702 
1703 /* calculate the first block number of the group */
1704 static inline ext4_fsblk_t
1705 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1706 {
1707         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1708                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1709 }
1710 
1711 /*
1712  * Special error return code only used by dx_probe() and its callers.
1713  */
1714 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
1715 
1716 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1717                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1718 
1719 /*
1720  * Timeout and state flag for lazy initialization inode thread.
1721  */
1722 #define EXT4_DEF_LI_WAIT_MULT                   10
1723 #define EXT4_DEF_LI_MAX_START_DELAY             5
1724 #define EXT4_LAZYINIT_QUIT                      0x0001
1725 #define EXT4_LAZYINIT_RUNNING                   0x0002
1726 
1727 /*
1728  * Lazy inode table initialization info
1729  */
1730 struct ext4_lazy_init {
1731         unsigned long           li_state;
1732         struct list_head        li_request_list;
1733         struct mutex            li_list_mtx;
1734 };
1735 
1736 struct ext4_li_request {
1737         struct super_block      *lr_super;
1738         struct ext4_sb_info     *lr_sbi;
1739         ext4_group_t            lr_next_group;
1740         struct list_head        lr_request;
1741         unsigned long           lr_next_sched;
1742         unsigned long           lr_timeout;
1743 };
1744 
1745 struct ext4_features {
1746         struct kobject f_kobj;
1747         struct completion f_kobj_unregister;
1748 };
1749 
1750 /*
1751  * This structure will be used for multiple mount protection. It will be
1752  * written into the block number saved in the s_mmp_block field in the
1753  * superblock. Programs that check MMP should assume that if
1754  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1755  * to use the filesystem, regardless of how old the timestamp is.
1756  */
1757 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1758 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1759 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1760 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1761 
1762 struct mmp_struct {
1763         __le32  mmp_magic;              /* Magic number for MMP */
1764         __le32  mmp_seq;                /* Sequence no. updated periodically */
1765 
1766         /*
1767          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1768          * purposes and do not affect the correctness of the algorithm
1769          */
1770         __le64  mmp_time;               /* Time last updated */
1771         char    mmp_nodename[64];       /* Node which last updated MMP block */
1772         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1773 
1774         /*
1775          * mmp_check_interval is used to verify if the MMP block has been
1776          * updated on the block device. The value is updated based on the
1777          * maximum time to write the MMP block during an update cycle.
1778          */
1779         __le16  mmp_check_interval;
1780 
1781         __le16  mmp_pad1;
1782         __le32  mmp_pad2[227];
1783 };
1784 
1785 /* arguments passed to the mmp thread */
1786 struct mmpd_data {
1787         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1788         struct super_block *sb;  /* super block of the fs */
1789 };
1790 
1791 /*
1792  * Check interval multiplier
1793  * The MMP block is written every update interval and initially checked every
1794  * update interval x the multiplier (the value is then adapted based on the
1795  * write latency). The reason is that writes can be delayed under load and we
1796  * don't want readers to incorrectly assume that the filesystem is no longer
1797  * in use.
1798  */
1799 #define EXT4_MMP_CHECK_MULT             2UL
1800 
1801 /*
1802  * Minimum interval for MMP checking in seconds.
1803  */
1804 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1805 
1806 /*
1807  * Maximum interval for MMP checking in seconds.
1808  */
1809 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1810 
1811 /*
1812  * Function prototypes
1813  */
1814 
1815 /*
1816  * Ok, these declarations are also in <linux/kernel.h> but none of the
1817  * ext4 source programs needs to include it so they are duplicated here.
1818  */
1819 # define NORET_TYPE     /**/
1820 # define ATTRIB_NORET   __attribute__((noreturn))
1821 # define NORET_AND      noreturn,
1822 
1823 /* bitmap.c */
1824 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1825 
1826 /* balloc.c */
1827 extern unsigned int ext4_block_group(struct super_block *sb,
1828                         ext4_fsblk_t blocknr);
1829 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1830                         ext4_fsblk_t blocknr);
1831 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1832 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1833                         ext4_group_t group);
1834 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1835                                          ext4_fsblk_t goal,
1836                                          unsigned int flags,
1837                                          unsigned long *count,
1838                                          int *errp);
1839 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1840                                     s64 nclusters, unsigned int flags);
1841 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1842 extern void ext4_check_blocks_bitmap(struct super_block *);
1843 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1844                                                     ext4_group_t block_group,
1845                                                     struct buffer_head ** bh);
1846 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1847 
1848 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1849                                                 ext4_group_t block_group);
1850 extern int ext4_wait_block_bitmap(struct super_block *sb,
1851                                   ext4_group_t block_group,
1852                                   struct buffer_head *bh);
1853 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1854                                                   ext4_group_t block_group);
1855 extern void ext4_init_block_bitmap(struct super_block *sb,
1856                                    struct buffer_head *bh,
1857                                    ext4_group_t group,
1858                                    struct ext4_group_desc *desc);
1859 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1860                                               ext4_group_t block_group,
1861                                               struct ext4_group_desc *gdp);
1862 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1863                                            ext4_group_t block_group,
1864                                            struct ext4_group_desc *gdp);
1865 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1866 
1867 /* dir.c */
1868 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1869                                   struct file *,
1870                                   struct ext4_dir_entry_2 *,
1871                                   struct buffer_head *, unsigned int);
1872 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1873         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1874                                         (de), (bh), (offset)))
1875 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1876                                     __u32 minor_hash,
1877                                     struct ext4_dir_entry_2 *dirent);
1878 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1879 
1880 /* fsync.c */
1881 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1882 extern int ext4_flush_completed_IO(struct inode *);
1883 
1884 /* hash.c */
1885 extern int ext4fs_dirhash(const char *name, int len, struct
1886                           dx_hash_info *hinfo);
1887 
1888 /* ialloc.c */
1889 extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1890                                     const struct qstr *qstr, __u32 goal,
1891                                     uid_t *owner);
1892 extern void ext4_free_inode(handle_t *, struct inode *);
1893 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1894 extern unsigned long ext4_count_free_inodes(struct super_block *);
1895 extern unsigned long ext4_count_dirs(struct super_block *);
1896 extern void ext4_check_inodes_bitmap(struct super_block *);
1897 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1898 extern int ext4_init_inode_table(struct super_block *sb,
1899                                  ext4_group_t group, int barrier);
1900 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1901 
1902 /* mballoc.c */
1903 extern long ext4_mb_stats;
1904 extern long ext4_mb_max_to_scan;
1905 extern int ext4_mb_init(struct super_block *, int);
1906 extern int ext4_mb_release(struct super_block *);
1907 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1908                                 struct ext4_allocation_request *, int *);
1909 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1910 extern void ext4_discard_preallocations(struct inode *);
1911 extern int __init ext4_init_mballoc(void);
1912 extern void ext4_exit_mballoc(void);
1913 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1914                              struct buffer_head *bh, ext4_fsblk_t block,
1915                              unsigned long count, int flags);
1916 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1917                 ext4_group_t i, struct ext4_group_desc *desc);
1918 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1919                                 ext4_fsblk_t block, unsigned long count);
1920 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1921 
1922 /* inode.c */
1923 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1924                                                 ext4_lblk_t, int, int *);
1925 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1926                                                 ext4_lblk_t, int, int *);
1927 int ext4_get_block(struct inode *inode, sector_t iblock,
1928                                 struct buffer_head *bh_result, int create);
1929 
1930 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1931 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
1932 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1933 extern int  ext4_setattr(struct dentry *, struct iattr *);
1934 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1935                                 struct kstat *stat);
1936 extern void ext4_evict_inode(struct inode *);
1937 extern void ext4_clear_inode(struct inode *);
1938 extern int  ext4_sync_inode(handle_t *, struct inode *);
1939 extern void ext4_dirty_inode(struct inode *, int);
1940 extern int ext4_change_inode_journal_flag(struct inode *, int);
1941 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1942 extern int ext4_can_truncate(struct inode *inode);
1943 extern void ext4_truncate(struct inode *);
1944 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1945 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1946 extern void ext4_set_inode_flags(struct inode *);
1947 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1948 extern int ext4_alloc_da_blocks(struct inode *inode);
1949 extern void ext4_set_aops(struct inode *inode);
1950 extern int ext4_writepage_trans_blocks(struct inode *);
1951 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1952 extern int ext4_discard_partial_page_buffers(handle_t *handle,
1953                 struct address_space *mapping, loff_t from,
1954                 loff_t length, int flags);
1955 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1956 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1957 extern void ext4_da_update_reserve_space(struct inode *inode,
1958                                         int used, int quota_claim);
1959 
1960 /* indirect.c */
1961 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
1962                                 struct ext4_map_blocks *map, int flags);
1963 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
1964                                 const struct iovec *iov, loff_t offset,
1965                                 unsigned long nr_segs);
1966 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
1967 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
1968 extern void ext4_ind_truncate(struct inode *inode);
1969 
1970 /* ioctl.c */
1971 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1972 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1973 
1974 /* migrate.c */
1975 extern int ext4_ext_migrate(struct inode *);
1976 
1977 /* namei.c */
1978 extern int ext4_orphan_add(handle_t *, struct inode *);
1979 extern int ext4_orphan_del(handle_t *, struct inode *);
1980 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1981                                 __u32 start_minor_hash, __u32 *next_hash);
1982 
1983 /* resize.c */
1984 extern int ext4_group_add(struct super_block *sb,
1985                                 struct ext4_new_group_data *input);
1986 extern int ext4_group_extend(struct super_block *sb,
1987                                 struct ext4_super_block *es,
1988                                 ext4_fsblk_t n_blocks_count);
1989 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
1990 
1991 /* super.c */
1992 extern int ext4_calculate_overhead(struct super_block *sb);
1993 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
1994 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
1995 extern void ext4_kvfree(void *ptr);
1996 extern __printf(4, 5)
1997 void __ext4_error(struct super_block *, const char *, unsigned int,
1998                   const char *, ...);
1999 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2000                                                      __LINE__, ## message)
2001 extern __printf(5, 6)
2002 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2003                       const char *, ...);
2004 extern __printf(5, 6)
2005 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2006                      const char *, ...);
2007 extern void __ext4_std_error(struct super_block *, const char *,
2008                              unsigned int, int);
2009 extern __printf(4, 5)
2010 void __ext4_abort(struct super_block *, const char *, unsigned int,
2011                   const char *, ...);
2012 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2013                                                        __LINE__, ## message)
2014 extern __printf(4, 5)
2015 void __ext4_warning(struct super_block *, const char *, unsigned int,
2016                     const char *, ...);
2017 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2018                                                        __LINE__, ## message)
2019 extern __printf(3, 4)
2020 void ext4_msg(struct super_block *, const char *, const char *, ...);
2021 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2022                            const char *, unsigned int, const char *);
2023 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2024                                                        __LINE__, msg)
2025 extern __printf(7, 8)
2026 void __ext4_grp_locked_error(const char *, unsigned int,
2027                              struct super_block *, ext4_group_t,
2028                              unsigned long, ext4_fsblk_t,
2029                              const char *, ...);
2030 #define ext4_grp_locked_error(sb, grp, message...) \
2031         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2032 extern void ext4_update_dynamic_rev(struct super_block *sb);
2033 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2034                                         __u32 compat);
2035 extern int ext4_update_rocompat_feature(handle_t *handle,
2036                                         struct super_block *sb, __u32 rocompat);
2037 extern int ext4_update_incompat_feature(handle_t *handle,
2038                                         struct super_block *sb, __u32 incompat);
2039 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2040                                       struct ext4_group_desc *bg);
2041 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2042                                       struct ext4_group_desc *bg);
2043 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2044                                      struct ext4_group_desc *bg);
2045 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2046                                       struct ext4_group_desc *bg);
2047 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2048                                  struct ext4_group_desc *bg);
2049 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2050                                 struct ext4_group_desc *bg);
2051 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2052                                    struct ext4_group_desc *bg);
2053 extern void ext4_block_bitmap_set(struct super_block *sb,
2054                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2055 extern void ext4_inode_bitmap_set(struct super_block *sb,
2056                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2057 extern void ext4_inode_table_set(struct super_block *sb,
2058                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2059 extern void ext4_free_group_clusters_set(struct super_block *sb,
2060                                          struct ext4_group_desc *bg,
2061                                          __u32 count);
2062 extern void ext4_free_inodes_set(struct super_block *sb,
2063                                 struct ext4_group_desc *bg, __u32 count);
2064 extern void ext4_used_dirs_set(struct super_block *sb,
2065                                 struct ext4_group_desc *bg, __u32 count);
2066 extern void ext4_itable_unused_set(struct super_block *sb,
2067                                    struct ext4_group_desc *bg, __u32 count);
2068 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
2069                                    struct ext4_group_desc *gdp);
2070 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
2071                                        struct ext4_group_desc *gdp);
2072 
2073 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2074 {
2075         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2076                 le32_to_cpu(es->s_blocks_count_lo);
2077 }
2078 
2079 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2080 {
2081         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2082                 le32_to_cpu(es->s_r_blocks_count_lo);
2083 }
2084 
2085 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2086 {
2087         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2088                 le32_to_cpu(es->s_free_blocks_count_lo);
2089 }
2090 
2091 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2092                                          ext4_fsblk_t blk)
2093 {
2094         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2095         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2096 }
2097 
2098 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2099                                               ext4_fsblk_t blk)
2100 {
2101         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2102         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2103 }
2104 
2105 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2106                                            ext4_fsblk_t blk)
2107 {
2108         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2109         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2110 }
2111 
2112 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2113 {
2114         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2115                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2116                         le32_to_cpu(raw_inode->i_size_lo);
2117         else
2118                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2119 }
2120 
2121 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2122 {
2123         raw_inode->i_size_lo = cpu_to_le32(i_size);
2124         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2125 }
2126 
2127 static inline
2128 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2129                                             ext4_group_t group)
2130 {
2131          struct ext4_group_info ***grp_info;
2132          long indexv, indexh;
2133          grp_info = EXT4_SB(sb)->s_group_info;
2134          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2135          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2136          return grp_info[indexv][indexh];
2137 }
2138 
2139 /*
2140  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2141  * the locking protocol documented in the comments of ext4_group_add()
2142  * in resize.c
2143  */
2144 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2145 {
2146         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2147 
2148         smp_rmb();
2149         return ngroups;
2150 }
2151 
2152 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2153                                              ext4_group_t block_group)
2154 {
2155         return block_group >> sbi->s_log_groups_per_flex;
2156 }
2157 
2158 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2159 {
2160         return 1 << sbi->s_log_groups_per_flex;
2161 }
2162 
2163 #define ext4_std_error(sb, errno)                               \
2164 do {                                                            \
2165         if ((errno))                                            \
2166                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2167 } while (0)
2168 
2169 #ifdef CONFIG_SMP
2170 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2171  * counters. So we need to make sure we have free clusters more
2172  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2173  */
2174 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2175 #else
2176 #define EXT4_FREECLUSTERS_WATERMARK 0
2177 #endif
2178 
2179 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2180 {
2181         /*
2182          * XXX: replace with spinlock if seen contended -bzzz
2183          */
2184         down_write(&EXT4_I(inode)->i_data_sem);
2185         if (newsize > EXT4_I(inode)->i_disksize)
2186                 EXT4_I(inode)->i_disksize = newsize;
2187         up_write(&EXT4_I(inode)->i_data_sem);
2188         return ;
2189 }
2190 
2191 struct ext4_group_info {
2192         unsigned long   bb_state;
2193         struct rb_root  bb_free_root;
2194         ext4_grpblk_t   bb_first_free;  /* first free block */
2195         ext4_grpblk_t   bb_free;        /* total free blocks */
2196         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2197         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2198         struct          list_head bb_prealloc_list;
2199 #ifdef DOUBLE_CHECK
2200         void            *bb_bitmap;
2201 #endif
2202         struct rw_semaphore alloc_sem;
2203         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2204                                          * regions, index is order.
2205                                          * bb_counters[3] = 5 means
2206                                          * 5 free 8-block regions. */
2207 };
2208 
2209 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2210 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2211 
2212 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2213         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2214 
2215 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2216         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2217 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2218         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2219 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2220         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2221 
2222 #define EXT4_MAX_CONTENTION             8
2223 #define EXT4_CONTENTION_THRESHOLD       2
2224 
2225 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2226                                               ext4_group_t group)
2227 {
2228         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2229 }
2230 
2231 /*
2232  * Returns true if the filesystem is busy enough that attempts to
2233  * access the block group locks has run into contention.
2234  */
2235 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2236 {
2237         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2238 }
2239 
2240 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2241 {
2242         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2243         if (spin_trylock(lock))
2244                 /*
2245                  * We're able to grab the lock right away, so drop the
2246                  * lock contention counter.
2247                  */
2248                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2249         else {
2250                 /*
2251                  * The lock is busy, so bump the contention counter,
2252                  * and then wait on the spin lock.
2253                  */
2254                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2255                                   EXT4_MAX_CONTENTION);
2256                 spin_lock(lock);
2257         }
2258 }
2259 
2260 static inline void ext4_unlock_group(struct super_block *sb,
2261                                         ext4_group_t group)
2262 {
2263         spin_unlock(ext4_group_lock_ptr(sb, group));
2264 }
2265 
2266 static inline void ext4_mark_super_dirty(struct super_block *sb)
2267 {
2268         if (EXT4_SB(sb)->s_journal == NULL)
2269                 sb->s_dirt =1;
2270 }
2271 
2272 /*
2273  * Block validity checking
2274  */
2275 #define ext4_check_indirect_blockref(inode, bh)                         \
2276         ext4_check_blockref(__func__, __LINE__, inode,                  \
2277                             (__le32 *)(bh)->b_data,                     \
2278                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2279 
2280 #define ext4_ind_check_inode(inode)                                     \
2281         ext4_check_blockref(__func__, __LINE__, inode,                  \
2282                             EXT4_I(inode)->i_data,                      \
2283                             EXT4_NDIR_BLOCKS)
2284 
2285 /*
2286  * Inodes and files operations
2287  */
2288 
2289 /* dir.c */
2290 extern const struct file_operations ext4_dir_operations;
2291 
2292 /* file.c */
2293 extern const struct inode_operations ext4_file_inode_operations;
2294 extern const struct file_operations ext4_file_operations;
2295 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2296 
2297 /* namei.c */
2298 extern const struct inode_operations ext4_dir_inode_operations;
2299 extern const struct inode_operations ext4_special_inode_operations;
2300 extern struct dentry *ext4_get_parent(struct dentry *child);
2301 
2302 /* symlink.c */
2303 extern const struct inode_operations ext4_symlink_inode_operations;
2304 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2305 
2306 /* block_validity */
2307 extern void ext4_release_system_zone(struct super_block *sb);
2308 extern int ext4_setup_system_zone(struct super_block *sb);
2309 extern int __init ext4_init_system_zone(void);
2310 extern void ext4_exit_system_zone(void);
2311 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2312                                  ext4_fsblk_t start_blk,
2313                                  unsigned int count);
2314 extern int ext4_check_blockref(const char *, unsigned int,
2315                                struct inode *, __le32 *, unsigned int);
2316 
2317 /* extents.c */
2318 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2319 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2320 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2321                                        int chunk);
2322 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2323                                struct ext4_map_blocks *map, int flags);
2324 extern void ext4_ext_truncate(struct inode *);
2325 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2326                                 loff_t length);
2327 extern void ext4_ext_init(struct super_block *);
2328 extern void ext4_ext_release(struct super_block *);
2329 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2330                           loff_t len);
2331 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2332                           ssize_t len);
2333 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2334                            struct ext4_map_blocks *map, int flags);
2335 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2336                         __u64 start, __u64 len);
2337 /* move_extent.c */
2338 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2339                              __u64 start_orig, __u64 start_donor,
2340                              __u64 len, __u64 *moved_len);
2341 
2342 /* page-io.c */
2343 extern int __init ext4_init_pageio(void);
2344 extern void ext4_exit_pageio(void);
2345 extern void ext4_ioend_wait(struct inode *);
2346 extern void ext4_free_io_end(ext4_io_end_t *io);
2347 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2348 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2349 extern void ext4_io_submit(struct ext4_io_submit *io);
2350 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2351                                struct page *page,
2352                                int len,
2353                                struct writeback_control *wbc);
2354 
2355 /* mmp.c */
2356 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2357 
2358 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2359 enum ext4_state_bits {
2360         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2361           = BH_JBDPrivateStart,
2362         BH_AllocFromCluster,    /* allocated blocks were part of already
2363                                  * allocated cluster. Note that this flag will
2364                                  * never, ever appear in a buffer_head's state
2365                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2366                                  * this is used. */
2367         BH_Da_Mapped,   /* Delayed allocated block that now has a mapping. This
2368                          * flag is set when ext4_map_blocks is called on a
2369                          * delayed allocated block to get its real mapping. */
2370 };
2371 
2372 BUFFER_FNS(Uninit, uninit)
2373 TAS_BUFFER_FNS(Uninit, uninit)
2374 BUFFER_FNS(Da_Mapped, da_mapped)
2375 
2376 /*
2377  * Add new method to test wether block and inode bitmaps are properly
2378  * initialized. With uninit_bg reading the block from disk is not enough
2379  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2380  */
2381 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2382 
2383 static inline int bitmap_uptodate(struct buffer_head *bh)
2384 {
2385         return (buffer_uptodate(bh) &&
2386                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2387 }
2388 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2389 {
2390         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2391 }
2392 
2393 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2394 
2395 /* For ioend & aio unwritten conversion wait queues */
2396 #define EXT4_WQ_HASH_SZ         37
2397 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2398                                             EXT4_WQ_HASH_SZ])
2399 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2400                                              EXT4_WQ_HASH_SZ])
2401 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2402 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2403 
2404 #define EXT4_RESIZING   0
2405 extern int ext4_resize_begin(struct super_block *sb);
2406 extern void ext4_resize_end(struct super_block *sb);
2407 
2408 #endif  /* __KERNEL__ */
2409 
2410 #include "ext4_extents.h"
2411 
2412 #endif  /* _EXT4_H */
2413 

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