1/*
2 *  ext4.h
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 *  from
10 *
11 *  linux/include/linux/minix_fs.h
12 *
13 *  Copyright (C) 1991, 1992  Linus Torvalds
14 */
15
16#ifndef _EXT4_H
17#define _EXT4_H
18
19#include <linux/types.h>
20#include <linux/blkdev.h>
21#include <linux/magic.h>
22#include <linux/jbd2.h>
23#include <linux/quota.h>
24#include <linux/rwsem.h>
25#include <linux/rbtree.h>
26#include <linux/seqlock.h>
27#include <linux/mutex.h>
28#include <linux/timer.h>
29#include <linux/wait.h>
30#include <linux/blockgroup_lock.h>
31#include <linux/percpu_counter.h>
32#ifdef __KERNEL__
33#include <linux/compat.h>
34#endif
35
36/*
37 * The fourth extended filesystem constants/structures
38 */
39
40/*
41 * Define EXT4FS_DEBUG to produce debug messages
42 */
43#undef EXT4FS_DEBUG
44
45/*
46 * Debug code
47 */
48#ifdef EXT4FS_DEBUG
49#define ext4_debug(f, a...)						\
50	do {								\
51		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
52			__FILE__, __LINE__, __func__);			\
53		printk(KERN_DEBUG f, ## a);				\
54	} while (0)
55#else
56#define ext4_debug(f, a...)	do {} while (0)
57#endif
58
59#define EXT4_ERROR_INODE(inode, fmt, a...) \
60	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
61
62#define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
63	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
64
65#define EXT4_ERROR_FILE(file, fmt, a...)	\
66	ext4_error_file(__func__, __LINE__, (file), (fmt), ## a)
67
68/* data type for block offset of block group */
69typedef int ext4_grpblk_t;
70
71/* data type for filesystem-wide blocks number */
72typedef unsigned long long ext4_fsblk_t;
73
74/* data type for file logical block number */
75typedef __u32 ext4_lblk_t;
76
77/* data type for block group number */
78typedef unsigned int ext4_group_t;
79
80/*
81 * Flags used in mballoc's allocation_context flags field.
82 *
83 * Also used to show what's going on for debugging purposes when the
84 * flag field is exported via the traceport interface
85 */
86
87/* prefer goal again. length */
88#define EXT4_MB_HINT_MERGE		0x0001
89/* blocks already reserved */
90#define EXT4_MB_HINT_RESERVED		0x0002
91/* metadata is being allocated */
92#define EXT4_MB_HINT_METADATA		0x0004
93/* first blocks in the file */
94#define EXT4_MB_HINT_FIRST		0x0008
95/* search for the best chunk */
96#define EXT4_MB_HINT_BEST		0x0010
97/* data is being allocated */
98#define EXT4_MB_HINT_DATA		0x0020
99/* don't preallocate (for tails) */
100#define EXT4_MB_HINT_NOPREALLOC		0x0040
101/* allocate for locality group */
102#define EXT4_MB_HINT_GROUP_ALLOC	0x0080
103/* allocate goal blocks or none */
104#define EXT4_MB_HINT_GOAL_ONLY		0x0100
105/* goal is meaningful */
106#define EXT4_MB_HINT_TRY_GOAL		0x0200
107/* blocks already pre-reserved by delayed allocation */
108#define EXT4_MB_DELALLOC_RESERVED	0x0400
109/* We are doing stream allocation */
110#define EXT4_MB_STREAM_ALLOC		0x0800
111
112
113struct ext4_allocation_request {
114	/* target inode for block we're allocating */
115	struct inode *inode;
116	/* how many blocks we want to allocate */
117	unsigned int len;
118	/* logical block in target inode */
119	ext4_lblk_t logical;
120	/* the closest logical allocated block to the left */
121	ext4_lblk_t lleft;
122	/* the closest logical allocated block to the right */
123	ext4_lblk_t lright;
124	/* phys. target (a hint) */
125	ext4_fsblk_t goal;
126	/* phys. block for the closest logical allocated block to the left */
127	ext4_fsblk_t pleft;
128	/* phys. block for the closest logical allocated block to the right */
129	ext4_fsblk_t pright;
130	/* flags. see above EXT4_MB_HINT_* */
131	unsigned int flags;
132};
133
134/*
135 * Logical to physical block mapping, used by ext4_map_blocks()
136 *
137 * This structure is used to pass requests into ext4_map_blocks() as
138 * well as to store the information returned by ext4_map_blocks().  It
139 * takes less room on the stack than a struct buffer_head.
140 */
141#define EXT4_MAP_NEW		(1 << BH_New)
142#define EXT4_MAP_MAPPED		(1 << BH_Mapped)
143#define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
144#define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
145#define EXT4_MAP_UNINIT		(1 << BH_Uninit)
146#define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
147				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
148				 EXT4_MAP_UNINIT)
149
150struct ext4_map_blocks {
151	ext4_fsblk_t m_pblk;
152	ext4_lblk_t m_lblk;
153	unsigned int m_len;
154	unsigned int m_flags;
155};
156
157/*
158 * For delayed allocation tracking
159 */
160struct mpage_da_data {
161	struct inode *inode;
162	sector_t b_blocknr;		/* start block number of extent */
163	size_t b_size;			/* size of extent */
164	unsigned long b_state;		/* state of the extent */
165	unsigned long first_page, next_page;	/* extent of pages */
166	struct writeback_control *wbc;
167	int io_done;
168	int pages_written;
169	int retval;
170};
171#define	EXT4_IO_UNWRITTEN	0x1
172typedef struct ext4_io_end {
173	struct list_head	list;		/* per-file finished IO list */
174	struct inode		*inode;		/* file being written to */
175	unsigned int		flag;		/* unwritten or not */
176	struct page		*page;		/* page struct for buffer write */
177	loff_t			offset;		/* offset in the file */
178	ssize_t			size;		/* size of the extent */
179	struct work_struct	work;		/* data work queue */
180	struct kiocb		*iocb;		/* iocb struct for AIO */
181	int			result;		/* error value for AIO */
182} ext4_io_end_t;
183
184/*
185 * Special inodes numbers
186 */
187#define	EXT4_BAD_INO		 1	/* Bad blocks inode */
188#define EXT4_ROOT_INO		 2	/* Root inode */
189#define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
190#define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
191#define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
192#define EXT4_JOURNAL_INO	 8	/* Journal inode */
193
194/* First non-reserved inode for old ext4 filesystems */
195#define EXT4_GOOD_OLD_FIRST_INO	11
196
197/*
198 * Maximal count of links to a file
199 */
200#define EXT4_LINK_MAX		65000
201
202/*
203 * Macro-instructions used to manage several block sizes
204 */
205#define EXT4_MIN_BLOCK_SIZE		1024
206#define	EXT4_MAX_BLOCK_SIZE		65536
207#define EXT4_MIN_BLOCK_LOG_SIZE		10
208#ifdef __KERNEL__
209# define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
210#else
211# define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
212#endif
213#define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
214#ifdef __KERNEL__
215# define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
216#else
217# define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
218#endif
219#ifdef __KERNEL__
220#define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
221#define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
222#define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
223#else
224#define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
225				 EXT4_GOOD_OLD_INODE_SIZE : \
226				 (s)->s_inode_size)
227#define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
228				 EXT4_GOOD_OLD_FIRST_INO : \
229				 (s)->s_first_ino)
230#endif
231#define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
232
233/*
234 * Structure of a blocks group descriptor
235 */
236struct ext4_group_desc
237{
238	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
239	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
240	__le32	bg_inode_table_lo;	/* Inodes table block */
241	__le16	bg_free_blocks_count_lo;/* Free blocks count */
242	__le16	bg_free_inodes_count_lo;/* Free inodes count */
243	__le16	bg_used_dirs_count_lo;	/* Directories count */
244	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
245	__u32	bg_reserved[2];		/* Likely block/inode bitmap checksum */
246	__le16  bg_itable_unused_lo;	/* Unused inodes count */
247	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
248	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
249	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
250	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
251	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
252	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
253	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
254	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
255	__u32	bg_reserved2[3];
256};
257
258/*
259 * Structure of a flex block group info
260 */
261
262struct flex_groups {
263	atomic_t free_inodes;
264	atomic_t free_blocks;
265	atomic_t used_dirs;
266};
267
268#define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
269#define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
270#define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
271
272/*
273 * Macro-instructions used to manage group descriptors
274 */
275#define EXT4_MIN_DESC_SIZE		32
276#define EXT4_MIN_DESC_SIZE_64BIT	64
277#define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
278#define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
279#ifdef __KERNEL__
280# define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
281# define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
282# define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
283# define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
284#else
285# define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
286# define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
287# define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
288#endif
289
290/*
291 * Constants relative to the data blocks
292 */
293#define	EXT4_NDIR_BLOCKS		12
294#define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
295#define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
296#define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
297#define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
298
299/*
300 * Inode flags
301 */
302#define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
303#define	EXT4_UNRM_FL			0x00000002 /* Undelete */
304#define	EXT4_COMPR_FL			0x00000004 /* Compress file */
305#define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
306#define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
307#define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
308#define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
309#define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
310/* Reserved for compression usage... */
311#define EXT4_DIRTY_FL			0x00000100
312#define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
313#define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
314#define EXT4_ECOMPR_FL			0x00000800 /* Compression error */
315/* End compression flags --- maybe not all used */
316#define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
317#define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
318#define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
319#define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
320#define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
321#define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
322#define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
323#define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
324#define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
325#define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
326#define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
327
328#define EXT4_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
329#define EXT4_FL_USER_MODIFIABLE		0x004B80FF /* User modifiable flags */
330
331/* Flags that should be inherited by new inodes from their parent. */
332#define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
333			   EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
334			   EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
335			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
336			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
337
338/* Flags that are appropriate for regular files (all but dir-specific ones). */
339#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
340
341/* Flags that are appropriate for non-directories/regular files. */
342#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
343
344/* Mask out flags that are inappropriate for the given type of inode. */
345static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
346{
347	if (S_ISDIR(mode))
348		return flags;
349	else if (S_ISREG(mode))
350		return flags & EXT4_REG_FLMASK;
351	else
352		return flags & EXT4_OTHER_FLMASK;
353}
354
355/*
356 * Inode flags used for atomic set/get
357 */
358enum {
359	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
360	EXT4_INODE_UNRM		= 1,	/* Undelete */
361	EXT4_INODE_COMPR	= 2,	/* Compress file */
362	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
363	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
364	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
365	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
366	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
367/* Reserved for compression usage... */
368	EXT4_INODE_DIRTY	= 8,
369	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
370	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
371	EXT4_INODE_ECOMPR	= 11,	/* Compression error */
372/* End compression flags --- maybe not all used */
373	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
374	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
375	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
376	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
377	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
378	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
379	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
380	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
381	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
382	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
383	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
384};
385
386#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
387#define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
388	printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
389		EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
390
391/*
392 * Since it's pretty easy to mix up bit numbers and hex values, and we
393 * can't do a compile-time test for ENUM values, we use a run-time
394 * test to make sure that EXT4_XXX_FL is consistent with respect to
395 * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
396 * out so it won't cost any extra space in the compiled kernel image.
397 * But it's important that these values are the same, since we are
398 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
399 * must be consistent with the values of FS_XXX_FL defined in
400 * include/linux/fs.h and the on-disk values found in ext2, ext3, and
401 * ext4 filesystems, and of course the values defined in e2fsprogs.
402 *
403 * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
404 */
405static inline void ext4_check_flag_values(void)
406{
407	CHECK_FLAG_VALUE(SECRM);
408	CHECK_FLAG_VALUE(UNRM);
409	CHECK_FLAG_VALUE(COMPR);
410	CHECK_FLAG_VALUE(SYNC);
411	CHECK_FLAG_VALUE(IMMUTABLE);
412	CHECK_FLAG_VALUE(APPEND);
413	CHECK_FLAG_VALUE(NODUMP);
414	CHECK_FLAG_VALUE(NOATIME);
415	CHECK_FLAG_VALUE(DIRTY);
416	CHECK_FLAG_VALUE(COMPRBLK);
417	CHECK_FLAG_VALUE(NOCOMPR);
418	CHECK_FLAG_VALUE(ECOMPR);
419	CHECK_FLAG_VALUE(INDEX);
420	CHECK_FLAG_VALUE(IMAGIC);
421	CHECK_FLAG_VALUE(JOURNAL_DATA);
422	CHECK_FLAG_VALUE(NOTAIL);
423	CHECK_FLAG_VALUE(DIRSYNC);
424	CHECK_FLAG_VALUE(TOPDIR);
425	CHECK_FLAG_VALUE(HUGE_FILE);
426	CHECK_FLAG_VALUE(EXTENTS);
427	CHECK_FLAG_VALUE(EA_INODE);
428	CHECK_FLAG_VALUE(EOFBLOCKS);
429	CHECK_FLAG_VALUE(RESERVED);
430}
431
432/* Used to pass group descriptor data when online resize is done */
433struct ext4_new_group_input {
434	__u32 group;		/* Group number for this data */
435	__u64 block_bitmap;	/* Absolute block number of block bitmap */
436	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
437	__u64 inode_table;	/* Absolute block number of inode table start */
438	__u32 blocks_count;	/* Total number of blocks in this group */
439	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
440	__u16 unused;
441};
442
443#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
444struct compat_ext4_new_group_input {
445	u32 group;
446	compat_u64 block_bitmap;
447	compat_u64 inode_bitmap;
448	compat_u64 inode_table;
449	u32 blocks_count;
450	u16 reserved_blocks;
451	u16 unused;
452};
453#endif
454
455/* The struct ext4_new_group_input in kernel space, with free_blocks_count */
456struct ext4_new_group_data {
457	__u32 group;
458	__u64 block_bitmap;
459	__u64 inode_bitmap;
460	__u64 inode_table;
461	__u32 blocks_count;
462	__u16 reserved_blocks;
463	__u16 unused;
464	__u32 free_blocks_count;
465};
466
467/*
468 * Flags used by ext4_map_blocks()
469 */
470	/* Allocate any needed blocks and/or convert an unitialized
471	   extent to be an initialized ext4 */
472#define EXT4_GET_BLOCKS_CREATE			0x0001
473	/* Request the creation of an unitialized extent */
474#define EXT4_GET_BLOCKS_UNINIT_EXT		0x0002
475#define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT	(EXT4_GET_BLOCKS_UNINIT_EXT|\
476						 EXT4_GET_BLOCKS_CREATE)
477	/* Caller is from the delayed allocation writeout path,
478	   so set the magic i_delalloc_reserve_flag after taking the
479	   inode allocation semaphore for */
480#define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
481	/* caller is from the direct IO path, request to creation of an
482	unitialized extents if not allocated, split the uninitialized
483	extent if blocks has been preallocated already*/
484#define EXT4_GET_BLOCKS_PRE_IO			0x0008
485#define EXT4_GET_BLOCKS_CONVERT			0x0010
486#define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
487					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
488	/* Convert extent to initialized after IO complete */
489#define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
490					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
491
492/*
493 * Flags used by ext4_free_blocks
494 */
495#define EXT4_FREE_BLOCKS_METADATA	0x0001
496#define EXT4_FREE_BLOCKS_FORGET		0x0002
497#define EXT4_FREE_BLOCKS_VALIDATED	0x0004
498
499/*
500 * ioctl commands
501 */
502#define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
503#define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
504#define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
505#define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
506#define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
507#define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
508#ifdef CONFIG_JBD2_DEBUG
509#define EXT4_IOC_WAIT_FOR_READONLY	_IOR('f', 99, long)
510#endif
511#define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
512#define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
513#define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
514#define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
515#define EXT4_IOC_MIGRATE		_IO('f', 9)
516 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
517 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
518#define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
519#define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
520
521#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
522/*
523 * ioctl commands in 32 bit emulation
524 */
525#define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
526#define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
527#define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
528#define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
529#define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
530#define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
531#define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
532#define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
533#ifdef CONFIG_JBD2_DEBUG
534#define EXT4_IOC32_WAIT_FOR_READONLY	_IOR('f', 99, int)
535#endif
536#define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
537#define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
538#endif
539
540
541/*
542 *  Mount options
543 */
544struct ext4_mount_options {
545	unsigned long s_mount_opt;
546	uid_t s_resuid;
547	gid_t s_resgid;
548	unsigned long s_commit_interval;
549	u32 s_min_batch_time, s_max_batch_time;
550#ifdef CONFIG_QUOTA
551	int s_jquota_fmt;
552	char *s_qf_names[MAXQUOTAS];
553#endif
554};
555
556/* Max physical block we can addres w/o extents */
557#define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
558
559/*
560 * Structure of an inode on the disk
561 */
562struct ext4_inode {
563	__le16	i_mode;		/* File mode */
564	__le16	i_uid;		/* Low 16 bits of Owner Uid */
565	__le32	i_size_lo;	/* Size in bytes */
566	__le32	i_atime;	/* Access time */
567	__le32	i_ctime;	/* Inode Change time */
568	__le32	i_mtime;	/* Modification time */
569	__le32	i_dtime;	/* Deletion Time */
570	__le16	i_gid;		/* Low 16 bits of Group Id */
571	__le16	i_links_count;	/* Links count */
572	__le32	i_blocks_lo;	/* Blocks count */
573	__le32	i_flags;	/* File flags */
574	union {
575		struct {
576			__le32  l_i_version;
577		} linux1;
578		struct {
579			__u32  h_i_translator;
580		} hurd1;
581		struct {
582			__u32  m_i_reserved1;
583		} masix1;
584	} osd1;				/* OS dependent 1 */
585	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
586	__le32	i_generation;	/* File version (for NFS) */
587	__le32	i_file_acl_lo;	/* File ACL */
588	__le32	i_size_high;
589	__le32	i_obso_faddr;	/* Obsoleted fragment address */
590	union {
591		struct {
592			__le16	l_i_blocks_high; /* were l_i_reserved1 */
593			__le16	l_i_file_acl_high;
594			__le16	l_i_uid_high;	/* these 2 fields */
595			__le16	l_i_gid_high;	/* were reserved2[0] */
596			__u32	l_i_reserved2;
597		} linux2;
598		struct {
599			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
600			__u16	h_i_mode_high;
601			__u16	h_i_uid_high;
602			__u16	h_i_gid_high;
603			__u32	h_i_author;
604		} hurd2;
605		struct {
606			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
607			__le16	m_i_file_acl_high;
608			__u32	m_i_reserved2[2];
609		} masix2;
610	} osd2;				/* OS dependent 2 */
611	__le16	i_extra_isize;
612	__le16	i_pad1;
613	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
614	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
615	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
616	__le32  i_crtime;       /* File Creation time */
617	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
618	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
619};
620
621struct move_extent {
622	__u32 reserved;		/* should be zero */
623	__u32 donor_fd;		/* donor file descriptor */
624	__u64 orig_start;	/* logical start offset in block for orig */
625	__u64 donor_start;	/* logical start offset in block for donor */
626	__u64 len;		/* block length to be moved */
627	__u64 moved_len;	/* moved block length */
628};
629
630#define EXT4_EPOCH_BITS 2
631#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
632#define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
633
634/*
635 * Extended fields will fit into an inode if the filesystem was formatted
636 * with large inodes (-I 256 or larger) and there are not currently any EAs
637 * consuming all of the available space. For new inodes we always reserve
638 * enough space for the kernel's known extended fields, but for inodes
639 * created with an old kernel this might not have been the case. None of
640 * the extended inode fields is critical for correct filesystem operation.
641 * This macro checks if a certain field fits in the inode. Note that
642 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
643 */
644#define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
645	((offsetof(typeof(*ext4_inode), field) +	\
646	  sizeof((ext4_inode)->field))			\
647	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
648	    (einode)->i_extra_isize))			\
649
650static inline __le32 ext4_encode_extra_time(struct timespec *time)
651{
652       return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
653			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
654                          ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
655}
656
657static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
658{
659       if (sizeof(time->tv_sec) > 4)
660	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
661			       << 32;
662       time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
663}
664
665#define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
666do {									       \
667	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
668	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
669		(raw_inode)->xtime ## _extra =				       \
670				ext4_encode_extra_time(&(inode)->xtime);       \
671} while (0)
672
673#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
674do {									       \
675	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
676		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
677	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
678		(raw_inode)->xtime ## _extra =				       \
679				ext4_encode_extra_time(&(einode)->xtime);      \
680} while (0)
681
682#define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
683do {									       \
684	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
685	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
686		ext4_decode_extra_time(&(inode)->xtime,			       \
687				       raw_inode->xtime ## _extra);	       \
688} while (0)
689
690#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
691do {									       \
692	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
693		(einode)->xtime.tv_sec = 				       \
694			(signed)le32_to_cpu((raw_inode)->xtime);	       \
695	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
696		ext4_decode_extra_time(&(einode)->xtime,		       \
697				       raw_inode->xtime ## _extra);	       \
698} while (0)
699
700#define i_disk_version osd1.linux1.l_i_version
701
702#if defined(__KERNEL__) || defined(__linux__)
703#define i_reserved1	osd1.linux1.l_i_reserved1
704#define i_file_acl_high	osd2.linux2.l_i_file_acl_high
705#define i_blocks_high	osd2.linux2.l_i_blocks_high
706#define i_uid_low	i_uid
707#define i_gid_low	i_gid
708#define i_uid_high	osd2.linux2.l_i_uid_high
709#define i_gid_high	osd2.linux2.l_i_gid_high
710#define i_reserved2	osd2.linux2.l_i_reserved2
711
712#elif defined(__GNU__)
713
714#define i_translator	osd1.hurd1.h_i_translator
715#define i_uid_high	osd2.hurd2.h_i_uid_high
716#define i_gid_high	osd2.hurd2.h_i_gid_high
717#define i_author	osd2.hurd2.h_i_author
718
719#elif defined(__masix__)
720
721#define i_reserved1	osd1.masix1.m_i_reserved1
722#define i_file_acl_high	osd2.masix2.m_i_file_acl_high
723#define i_reserved2	osd2.masix2.m_i_reserved2
724
725#endif /* defined(__KERNEL__) || defined(__linux__) */
726
727/*
728 * storage for cached extent
729 */
730struct ext4_ext_cache {
731	ext4_fsblk_t	ec_start;
732	ext4_lblk_t	ec_block;
733	__u32		ec_len; /* must be 32bit to return holes */
734	__u32		ec_type;
735};
736
737/*
738 * fourth extended file system inode data in memory
739 */
740struct ext4_inode_info {
741	__le32	i_data[15];	/* unconverted */
742	__u32	i_dtime;
743	ext4_fsblk_t	i_file_acl;
744
745	/*
746	 * i_block_group is the number of the block group which contains
747	 * this file's inode.  Constant across the lifetime of the inode,
748	 * it is ued for making block allocation decisions - we try to
749	 * place a file's data blocks near its inode block, and new inodes
750	 * near to their parent directory's inode.
751	 */
752	ext4_group_t	i_block_group;
753	unsigned long	i_state_flags;		/* Dynamic state flags */
754	unsigned long	i_flags;
755
756	ext4_lblk_t		i_dir_start_lookup;
757#ifdef CONFIG_EXT4_FS_XATTR
758	/*
759	 * Extended attributes can be read independently of the main file
760	 * data. Taking i_mutex even when reading would cause contention
761	 * between readers of EAs and writers of regular file data, so
762	 * instead we synchronize on xattr_sem when reading or changing
763	 * EAs.
764	 */
765	struct rw_semaphore xattr_sem;
766#endif
767
768	struct list_head i_orphan;	/* unlinked but open inodes */
769
770	/*
771	 * i_disksize keeps track of what the inode size is ON DISK, not
772	 * in memory.  During truncate, i_size is set to the new size by
773	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
774	 * set i_disksize to 0 until the truncate is actually under way.
775	 *
776	 * The intent is that i_disksize always represents the blocks which
777	 * are used by this file.  This allows recovery to restart truncate
778	 * on orphans if we crash during truncate.  We actually write i_disksize
779	 * into the on-disk inode when writing inodes out, instead of i_size.
780	 *
781	 * The only time when i_disksize and i_size may be different is when
782	 * a truncate is in progress.  The only things which change i_disksize
783	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
784	 */
785	loff_t	i_disksize;
786
787	/*
788	 * i_data_sem is for serialising ext4_truncate() against
789	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
790	 * data tree are chopped off during truncate. We can't do that in
791	 * ext4 because whenever we perform intermediate commits during
792	 * truncate, the inode and all the metadata blocks *must* be in a
793	 * consistent state which allows truncation of the orphans to restart
794	 * during recovery.  Hence we must fix the get_block-vs-truncate race
795	 * by other means, so we have i_data_sem.
796	 */
797	struct rw_semaphore i_data_sem;
798	struct inode vfs_inode;
799	struct jbd2_inode jinode;
800
801	struct ext4_ext_cache i_cached_extent;
802	/*
803	 * File creation time. Its function is same as that of
804	 * struct timespec i_{a,c,m}time in the generic inode.
805	 */
806	struct timespec i_crtime;
807
808	/* mballoc */
809	struct list_head i_prealloc_list;
810	spinlock_t i_prealloc_lock;
811
812	/* ialloc */
813	ext4_group_t	i_last_alloc_group;
814
815	/* allocation reservation info for delalloc */
816	unsigned int i_reserved_data_blocks;
817	unsigned int i_reserved_meta_blocks;
818	unsigned int i_allocated_meta_blocks;
819	unsigned short i_delalloc_reserved_flag;
820	sector_t i_da_metadata_calc_last_lblock;
821	int i_da_metadata_calc_len;
822
823	/* on-disk additional length */
824	__u16 i_extra_isize;
825
826	spinlock_t i_block_reservation_lock;
827#ifdef CONFIG_QUOTA
828	/* quota space reservation, managed internally by quota code */
829	qsize_t i_reserved_quota;
830#endif
831
832	/* completed IOs that might need unwritten extents handling */
833	struct list_head i_completed_io_list;
834	spinlock_t i_completed_io_lock;
835	/* current io_end structure for async DIO write*/
836	ext4_io_end_t *cur_aio_dio;
837
838	/*
839	 * Transactions that contain inode's metadata needed to complete
840	 * fsync and fdatasync, respectively.
841	 */
842	tid_t i_sync_tid;
843	tid_t i_datasync_tid;
844};
845
846/*
847 * File system states
848 */
849#define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
850#define	EXT4_ERROR_FS			0x0002	/* Errors detected */
851#define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
852
853/*
854 * Misc. filesystem flags
855 */
856#define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
857#define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
858#define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
859
860/*
861 * Mount flags
862 */
863#define EXT4_MOUNT_OLDALLOC		0x00002  /* Don't use the new Orlov allocator */
864#define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
865#define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
866#define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
867#define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
868#define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
869#define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
870#define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
871#define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
872#define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
873#define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
874#define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
875#define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
876#define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
877#define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
878#define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
879#define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
880#define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
881#define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
882#define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
883#define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
884#define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
885#define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
886#define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
887#define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
888#define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
889#define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
890#define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
891#define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
892
893#define clear_opt(o, opt)		o &= ~EXT4_MOUNT_##opt
894#define set_opt(o, opt)			o |= EXT4_MOUNT_##opt
895#define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
896					 EXT4_MOUNT_##opt)
897
898#define ext4_set_bit			ext2_set_bit
899#define ext4_set_bit_atomic		ext2_set_bit_atomic
900#define ext4_clear_bit			ext2_clear_bit
901#define ext4_clear_bit_atomic		ext2_clear_bit_atomic
902#define ext4_test_bit			ext2_test_bit
903#define ext4_find_first_zero_bit	ext2_find_first_zero_bit
904#define ext4_find_next_zero_bit		ext2_find_next_zero_bit
905#define ext4_find_next_bit		ext2_find_next_bit
906
907/*
908 * Maximal mount counts between two filesystem checks
909 */
910#define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
911#define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
912
913/*
914 * Behaviour when detecting errors
915 */
916#define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
917#define EXT4_ERRORS_RO			2	/* Remount fs read-only */
918#define EXT4_ERRORS_PANIC		3	/* Panic */
919#define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
920
921/*
922 * Structure of the super block
923 */
924struct ext4_super_block {
925/*00*/	__le32	s_inodes_count;		/* Inodes count */
926	__le32	s_blocks_count_lo;	/* Blocks count */
927	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
928	__le32	s_free_blocks_count_lo;	/* Free blocks count */
929/*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
930	__le32	s_first_data_block;	/* First Data Block */
931	__le32	s_log_block_size;	/* Block size */
932	__le32	s_obso_log_frag_size;	/* Obsoleted fragment size */
933/*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
934	__le32	s_obso_frags_per_group;	/* Obsoleted fragments per group */
935	__le32	s_inodes_per_group;	/* # Inodes per group */
936	__le32	s_mtime;		/* Mount time */
937/*30*/	__le32	s_wtime;		/* Write time */
938	__le16	s_mnt_count;		/* Mount count */
939	__le16	s_max_mnt_count;	/* Maximal mount count */
940	__le16	s_magic;		/* Magic signature */
941	__le16	s_state;		/* File system state */
942	__le16	s_errors;		/* Behaviour when detecting errors */
943	__le16	s_minor_rev_level;	/* minor revision level */
944/*40*/	__le32	s_lastcheck;		/* time of last check */
945	__le32	s_checkinterval;	/* max. time between checks */
946	__le32	s_creator_os;		/* OS */
947	__le32	s_rev_level;		/* Revision level */
948/*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
949	__le16	s_def_resgid;		/* Default gid for reserved blocks */
950	/*
951	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
952	 *
953	 * Note: the difference between the compatible feature set and
954	 * the incompatible feature set is that if there is a bit set
955	 * in the incompatible feature set that the kernel doesn't
956	 * know about, it should refuse to mount the filesystem.
957	 *
958	 * e2fsck's requirements are more strict; if it doesn't know
959	 * about a feature in either the compatible or incompatible
960	 * feature set, it must abort and not try to meddle with
961	 * things it doesn't understand...
962	 */
963	__le32	s_first_ino;		/* First non-reserved inode */
964	__le16  s_inode_size;		/* size of inode structure */
965	__le16	s_block_group_nr;	/* block group # of this superblock */
966	__le32	s_feature_compat;	/* compatible feature set */
967/*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
968	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
969/*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
970/*78*/	char	s_volume_name[16];	/* volume name */
971/*88*/	char	s_last_mounted[64];	/* directory where last mounted */
972/*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
973	/*
974	 * Performance hints.  Directory preallocation should only
975	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
976	 */
977	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
978	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
979	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
980	/*
981	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
982	 */
983/*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
984/*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
985	__le32	s_journal_dev;		/* device number of journal file */
986	__le32	s_last_orphan;		/* start of list of inodes to delete */
987	__le32	s_hash_seed[4];		/* HTREE hash seed */
988	__u8	s_def_hash_version;	/* Default hash version to use */
989	__u8	s_jnl_backup_type;
990	__le16  s_desc_size;		/* size of group descriptor */
991/*100*/	__le32	s_default_mount_opts;
992	__le32	s_first_meta_bg;	/* First metablock block group */
993	__le32	s_mkfs_time;		/* When the filesystem was created */
994	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
995	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
996/*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
997	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
998	__le32	s_free_blocks_count_hi;	/* Free blocks count */
999	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1000	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1001	__le32	s_flags;		/* Miscellaneous flags */
1002	__le16  s_raid_stride;		/* RAID stride */
1003	__le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
1004	__le64  s_mmp_block;            /* Block for multi-mount protection */
1005	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1006	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1007	__u8	s_reserved_char_pad;
1008	__le16  s_reserved_pad;
1009	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1010	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1011	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1012	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1013					      snapshot's future use */
1014	__le32	s_snapshot_list;	/* inode number of the head of the
1015					   on-disk snapshot list */
1016#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1017	__le32	s_error_count;		/* number of fs errors */
1018	__le32	s_first_error_time;	/* first time an error happened */
1019	__le32	s_first_error_ino;	/* inode involved in first error */
1020	__le64	s_first_error_block;	/* block involved of first error */
1021	__u8	s_first_error_func[32];	/* function where the error happened */
1022	__le32	s_first_error_line;	/* line number where error happened */
1023	__le32	s_last_error_time;	/* most recent time of an error */
1024	__le32	s_last_error_ino;	/* inode involved in last error */
1025	__le32	s_last_error_line;	/* line number where error happened */
1026	__le64	s_last_error_block;	/* block involved of last error */
1027	__u8	s_last_error_func[32];	/* function where the error happened */
1028#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1029	__u8	s_mount_opts[64];
1030	__le32	s_reserved[112];        /* Padding to the end of the block */
1031};
1032
1033#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1034
1035#ifdef __KERNEL__
1036
1037/*
1038 * run-time mount flags
1039 */
1040#define EXT4_MF_MNTDIR_SAMPLED	0x0001
1041#define EXT4_MF_FS_ABORTED	0x0002	/* Fatal error detected */
1042
1043/*
1044 * fourth extended-fs super-block data in memory
1045 */
1046struct ext4_sb_info {
1047	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1048	unsigned long s_inodes_per_block;/* Number of inodes per block */
1049	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1050	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1051	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1052	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1053	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1054	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1055	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1056	unsigned long s_overhead_last;  /* Last calculated overhead */
1057	unsigned long s_blocks_last;    /* Last seen block count */
1058	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1059	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1060	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1061	struct buffer_head **s_group_desc;
1062	unsigned int s_mount_opt;
1063	unsigned int s_mount_flags;
1064	ext4_fsblk_t s_sb_block;
1065	uid_t s_resuid;
1066	gid_t s_resgid;
1067	unsigned short s_mount_state;
1068	unsigned short s_pad;
1069	int s_addr_per_block_bits;
1070	int s_desc_per_block_bits;
1071	int s_inode_size;
1072	int s_first_ino;
1073	unsigned int s_inode_readahead_blks;
1074	unsigned int s_inode_goal;
1075	spinlock_t s_next_gen_lock;
1076	u32 s_next_generation;
1077	u32 s_hash_seed[4];
1078	int s_def_hash_version;
1079	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1080	struct percpu_counter s_freeblocks_counter;
1081	struct percpu_counter s_freeinodes_counter;
1082	struct percpu_counter s_dirs_counter;
1083	struct percpu_counter s_dirtyblocks_counter;
1084	struct blockgroup_lock *s_blockgroup_lock;
1085	struct proc_dir_entry *s_proc;
1086	struct kobject s_kobj;
1087	struct completion s_kobj_unregister;
1088
1089	/* Journaling */
1090	struct inode *s_journal_inode;
1091	struct journal_s *s_journal;
1092	struct list_head s_orphan;
1093	struct mutex s_orphan_lock;
1094	struct mutex s_resize_lock;
1095	unsigned long s_commit_interval;
1096	u32 s_max_batch_time;
1097	u32 s_min_batch_time;
1098	struct block_device *journal_bdev;
1099#ifdef CONFIG_JBD2_DEBUG
1100	struct timer_list turn_ro_timer;	/* For turning read-only (crash simulation) */
1101	wait_queue_head_t ro_wait_queue;	/* For people waiting for the fs to go read-only */
1102#endif
1103#ifdef CONFIG_QUOTA
1104	char *s_qf_names[MAXQUOTAS];		/* Names of quota files with journalled quota */
1105	int s_jquota_fmt;			/* Format of quota to use */
1106#endif
1107	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1108	struct rb_root system_blks;
1109
1110#ifdef EXTENTS_STATS
1111	/* ext4 extents stats */
1112	unsigned long s_ext_min;
1113	unsigned long s_ext_max;
1114	unsigned long s_depth_max;
1115	spinlock_t s_ext_stats_lock;
1116	unsigned long s_ext_blocks;
1117	unsigned long s_ext_extents;
1118#endif
1119
1120	/* for buddy allocator */
1121	struct ext4_group_info ***s_group_info;
1122	struct inode *s_buddy_cache;
1123	long s_blocks_reserved;
1124	spinlock_t s_reserve_lock;
1125	spinlock_t s_md_lock;
1126	tid_t s_last_transaction;
1127	unsigned short *s_mb_offsets;
1128	unsigned int *s_mb_maxs;
1129
1130	/* tunables */
1131	unsigned long s_stripe;
1132	unsigned int s_mb_stream_request;
1133	unsigned int s_mb_max_to_scan;
1134	unsigned int s_mb_min_to_scan;
1135	unsigned int s_mb_stats;
1136	unsigned int s_mb_order2_reqs;
1137	unsigned int s_mb_group_prealloc;
1138	unsigned int s_max_writeback_mb_bump;
1139	/* where last allocation was done - for stream allocation */
1140	unsigned long s_mb_last_group;
1141	unsigned long s_mb_last_start;
1142
1143	/* stats for buddy allocator */
1144	spinlock_t s_mb_pa_lock;
1145	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1146	atomic_t s_bal_success;	/* we found long enough chunks */
1147	atomic_t s_bal_allocated;	/* in blocks */
1148	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1149	atomic_t s_bal_goals;	/* goal hits */
1150	atomic_t s_bal_breaks;	/* too long searches */
1151	atomic_t s_bal_2orders;	/* 2^order hits */
1152	spinlock_t s_bal_lock;
1153	unsigned long s_mb_buddies_generated;
1154	unsigned long long s_mb_generation_time;
1155	atomic_t s_mb_lost_chunks;
1156	atomic_t s_mb_preallocated;
1157	atomic_t s_mb_discarded;
1158	atomic_t s_lock_busy;
1159
1160	/* locality groups */
1161	struct ext4_locality_group __percpu *s_locality_groups;
1162
1163	/* for write statistics */
1164	unsigned long s_sectors_written_start;
1165	u64 s_kbytes_written;
1166
1167	unsigned int s_log_groups_per_flex;
1168	struct flex_groups *s_flex_groups;
1169
1170	/* workqueue for dio unwritten */
1171	struct workqueue_struct *dio_unwritten_wq;
1172
1173	/* timer for periodic error stats printing */
1174	struct timer_list s_err_report;
1175};
1176
1177static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1178{
1179	return sb->s_fs_info;
1180}
1181static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1182{
1183	return container_of(inode, struct ext4_inode_info, vfs_inode);
1184}
1185
1186static inline struct timespec ext4_current_time(struct inode *inode)
1187{
1188	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1189		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1190}
1191
1192static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1193{
1194	return ino == EXT4_ROOT_INO ||
1195		ino == EXT4_JOURNAL_INO ||
1196		ino == EXT4_RESIZE_INO ||
1197		(ino >= EXT4_FIRST_INO(sb) &&
1198		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1199}
1200
1201/*
1202 * Inode dynamic state flags
1203 */
1204enum {
1205	EXT4_STATE_JDATA,		/* journaled data exists */
1206	EXT4_STATE_NEW,			/* inode is newly created */
1207	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1208	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1209	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1210	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1211	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1212	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1213};
1214
1215#define EXT4_INODE_BIT_FNS(name, field)					\
1216static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1217{									\
1218	return test_bit(bit, &EXT4_I(inode)->i_##field);		\
1219}									\
1220static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1221{									\
1222	set_bit(bit, &EXT4_I(inode)->i_##field);			\
1223}									\
1224static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1225{									\
1226	clear_bit(bit, &EXT4_I(inode)->i_##field);			\
1227}
1228
1229EXT4_INODE_BIT_FNS(flag, flags)
1230EXT4_INODE_BIT_FNS(state, state_flags)
1231#else
1232/* Assume that user mode programs are passing in an ext4fs superblock, not
1233 * a kernel struct super_block.  This will allow us to call the feature-test
1234 * macros from user land. */
1235#define EXT4_SB(sb)	(sb)
1236#endif
1237
1238#define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1239
1240/*
1241 * Codes for operating systems
1242 */
1243#define EXT4_OS_LINUX		0
1244#define EXT4_OS_HURD		1
1245#define EXT4_OS_MASIX		2
1246#define EXT4_OS_FREEBSD		3
1247#define EXT4_OS_LITES		4
1248
1249/*
1250 * Revision levels
1251 */
1252#define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1253#define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1254
1255#define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1256#define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1257
1258#define EXT4_GOOD_OLD_INODE_SIZE 128
1259
1260/*
1261 * Feature set definitions
1262 */
1263
1264#define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1265	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1266#define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1267	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1268#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1269	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1270#define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1271	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1272#define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1273	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1274#define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1275	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1276#define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1277	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1278#define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1279	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1280#define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1281	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1282
1283#define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1284#define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1285#define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1286#define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1287#define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1288#define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1289
1290#define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1291#define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1292#define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1293#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1294#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1295#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1296#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1297
1298#define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1299#define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1300#define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1301#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1302#define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1303#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1304#define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1305#define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1306#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1307#define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1308#define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1309
1310#define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
1311#define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1312					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1313					 EXT4_FEATURE_INCOMPAT_META_BG| \
1314					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1315					 EXT4_FEATURE_INCOMPAT_64BIT| \
1316					 EXT4_FEATURE_INCOMPAT_FLEX_BG)
1317#define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1318					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1319					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1320					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1321					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1322					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1323					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1324
1325/*
1326 * Default values for user and/or group using reserved blocks
1327 */
1328#define	EXT4_DEF_RESUID		0
1329#define	EXT4_DEF_RESGID		0
1330
1331#define EXT4_DEF_INODE_READAHEAD_BLKS	32
1332
1333/*
1334 * Default mount options
1335 */
1336#define EXT4_DEFM_DEBUG		0x0001
1337#define EXT4_DEFM_BSDGROUPS	0x0002
1338#define EXT4_DEFM_XATTR_USER	0x0004
1339#define EXT4_DEFM_ACL		0x0008
1340#define EXT4_DEFM_UID16		0x0010
1341#define EXT4_DEFM_JMODE		0x0060
1342#define EXT4_DEFM_JMODE_DATA	0x0020
1343#define EXT4_DEFM_JMODE_ORDERED	0x0040
1344#define EXT4_DEFM_JMODE_WBACK	0x0060
1345#define EXT4_DEFM_NOBARRIER	0x0100
1346#define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1347#define EXT4_DEFM_DISCARD	0x0400
1348#define EXT4_DEFM_NODELALLOC	0x0800
1349
1350/*
1351 * Default journal batch times
1352 */
1353#define EXT4_DEF_MIN_BATCH_TIME	0
1354#define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1355
1356/*
1357 * Minimum number of groups in a flexgroup before we separate out
1358 * directories into the first block group of a flexgroup
1359 */
1360#define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1361
1362/*
1363 * Structure of a directory entry
1364 */
1365#define EXT4_NAME_LEN 255
1366
1367struct ext4_dir_entry {
1368	__le32	inode;			/* Inode number */
1369	__le16	rec_len;		/* Directory entry length */
1370	__le16	name_len;		/* Name length */
1371	char	name[EXT4_NAME_LEN];	/* File name */
1372};
1373
1374/*
1375 * The new version of the directory entry.  Since EXT4 structures are
1376 * stored in intel byte order, and the name_len field could never be
1377 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1378 * file_type field.
1379 */
1380struct ext4_dir_entry_2 {
1381	__le32	inode;			/* Inode number */
1382	__le16	rec_len;		/* Directory entry length */
1383	__u8	name_len;		/* Name length */
1384	__u8	file_type;
1385	char	name[EXT4_NAME_LEN];	/* File name */
1386};
1387
1388/*
1389 * Ext4 directory file types.  Only the low 3 bits are used.  The
1390 * other bits are reserved for now.
1391 */
1392#define EXT4_FT_UNKNOWN		0
1393#define EXT4_FT_REG_FILE	1
1394#define EXT4_FT_DIR		2
1395#define EXT4_FT_CHRDEV		3
1396#define EXT4_FT_BLKDEV		4
1397#define EXT4_FT_FIFO		5
1398#define EXT4_FT_SOCK		6
1399#define EXT4_FT_SYMLINK		7
1400
1401#define EXT4_FT_MAX		8
1402
1403/*
1404 * EXT4_DIR_PAD defines the directory entries boundaries
1405 *
1406 * NOTE: It must be a multiple of 4
1407 */
1408#define EXT4_DIR_PAD			4
1409#define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1410#define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1411					 ~EXT4_DIR_ROUND)
1412#define EXT4_MAX_REC_LEN		((1<<16)-1)
1413
1414/*
1415 * If we ever get support for fs block sizes > page_size, we'll need
1416 * to remove the #if statements in the next two functions...
1417 */
1418static inline unsigned int
1419ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1420{
1421	unsigned len = le16_to_cpu(dlen);
1422
1423#if (PAGE_CACHE_SIZE >= 65536)
1424	if (len == EXT4_MAX_REC_LEN || len == 0)
1425		return blocksize;
1426	return (len & 65532) | ((len & 3) << 16);
1427#else
1428	return len;
1429#endif
1430}
1431
1432static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1433{
1434	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1435		BUG();
1436#if (PAGE_CACHE_SIZE >= 65536)
1437	if (len < 65536)
1438		return cpu_to_le16(len);
1439	if (len == blocksize) {
1440		if (blocksize == 65536)
1441			return cpu_to_le16(EXT4_MAX_REC_LEN);
1442		else
1443			return cpu_to_le16(0);
1444	}
1445	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1446#else
1447	return cpu_to_le16(len);
1448#endif
1449}
1450
1451/*
1452 * Hash Tree Directory indexing
1453 * (c) Daniel Phillips, 2001
1454 */
1455
1456#define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1457				      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1458		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1459#define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1460#define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1461
1462/* Legal values for the dx_root hash_version field: */
1463
1464#define DX_HASH_LEGACY		0
1465#define DX_HASH_HALF_MD4	1
1466#define DX_HASH_TEA		2
1467#define DX_HASH_LEGACY_UNSIGNED	3
1468#define DX_HASH_HALF_MD4_UNSIGNED	4
1469#define DX_HASH_TEA_UNSIGNED		5
1470
1471#ifdef __KERNEL__
1472
1473/* hash info structure used by the directory hash */
1474struct dx_hash_info
1475{
1476	u32		hash;
1477	u32		minor_hash;
1478	int		hash_version;
1479	u32		*seed;
1480};
1481
1482#define EXT4_HTREE_EOF	0x7fffffff
1483
1484/*
1485 * Control parameters used by ext4_htree_next_block
1486 */
1487#define HASH_NB_ALWAYS		1
1488
1489
1490/*
1491 * Describe an inode's exact location on disk and in memory
1492 */
1493struct ext4_iloc
1494{
1495	struct buffer_head *bh;
1496	unsigned long offset;
1497	ext4_group_t block_group;
1498};
1499
1500static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1501{
1502	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1503}
1504
1505/*
1506 * This structure is stuffed into the struct file's private_data field
1507 * for directories.  It is where we put information so that we can do
1508 * readdir operations in hash tree order.
1509 */
1510struct dir_private_info {
1511	struct rb_root	root;
1512	struct rb_node	*curr_node;
1513	struct fname	*extra_fname;
1514	loff_t		last_pos;
1515	__u32		curr_hash;
1516	__u32		curr_minor_hash;
1517	__u32		next_hash;
1518};
1519
1520/* calculate the first block number of the group */
1521static inline ext4_fsblk_t
1522ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1523{
1524	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1525		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1526}
1527
1528/*
1529 * Special error return code only used by dx_probe() and its callers.
1530 */
1531#define ERR_BAD_DX_DIR	-75000
1532
1533void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1534			ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1535
1536extern struct proc_dir_entry *ext4_proc_root;
1537
1538/*
1539 * Function prototypes
1540 */
1541
1542/*
1543 * Ok, these declarations are also in <linux/kernel.h> but none of the
1544 * ext4 source programs needs to include it so they are duplicated here.
1545 */
1546# define NORET_TYPE	/**/
1547# define ATTRIB_NORET	__attribute__((noreturn))
1548# define NORET_AND	noreturn,
1549
1550/* bitmap.c */
1551extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1552
1553/* balloc.c */
1554extern unsigned int ext4_block_group(struct super_block *sb,
1555			ext4_fsblk_t blocknr);
1556extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1557			ext4_fsblk_t blocknr);
1558extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1559extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1560			ext4_group_t group);
1561extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1562			ext4_fsblk_t goal, unsigned long *count, int *errp);
1563extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1564extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1565extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1566				ext4_fsblk_t block, unsigned long count);
1567extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1568extern void ext4_check_blocks_bitmap(struct super_block *);
1569extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1570						    ext4_group_t block_group,
1571						    struct buffer_head ** bh);
1572extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1573struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1574				      ext4_group_t block_group);
1575extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1576				       struct buffer_head *bh,
1577				       ext4_group_t group,
1578				       struct ext4_group_desc *desc);
1579#define ext4_free_blocks_after_init(sb, group, desc)			\
1580		ext4_init_block_bitmap(sb, NULL, group, desc)
1581
1582/* dir.c */
1583extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1584				  struct ext4_dir_entry_2 *,
1585				  struct buffer_head *, unsigned int);
1586#define ext4_check_dir_entry(dir, de, bh, offset) \
1587	__ext4_check_dir_entry(__func__, __LINE__, (dir), (de), (bh), (offset))
1588extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1589				    __u32 minor_hash,
1590				    struct ext4_dir_entry_2 *dirent);
1591extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1592
1593/* fsync.c */
1594extern int ext4_sync_file(struct file *, int);
1595
1596/* hash.c */
1597extern int ext4fs_dirhash(const char *name, int len, struct
1598			  dx_hash_info *hinfo);
1599
1600/* ialloc.c */
1601extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1602				    const struct qstr *qstr, __u32 goal);
1603extern void ext4_free_inode(handle_t *, struct inode *);
1604extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1605extern unsigned long ext4_count_free_inodes(struct super_block *);
1606extern unsigned long ext4_count_dirs(struct super_block *);
1607extern void ext4_check_inodes_bitmap(struct super_block *);
1608extern unsigned ext4_init_inode_bitmap(struct super_block *sb,
1609				       struct buffer_head *bh,
1610				       ext4_group_t group,
1611				       struct ext4_group_desc *desc);
1612extern void mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1613
1614/* mballoc.c */
1615extern long ext4_mb_stats;
1616extern long ext4_mb_max_to_scan;
1617extern int ext4_mb_init(struct super_block *, int);
1618extern int ext4_mb_release(struct super_block *);
1619extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1620				struct ext4_allocation_request *, int *);
1621extern int ext4_mb_reserve_blocks(struct super_block *, int);
1622extern void ext4_discard_preallocations(struct inode *);
1623extern int __init init_ext4_mballoc(void);
1624extern void exit_ext4_mballoc(void);
1625extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1626			     struct buffer_head *bh, ext4_fsblk_t block,
1627			     unsigned long count, int flags);
1628extern int ext4_mb_add_groupinfo(struct super_block *sb,
1629		ext4_group_t i, struct ext4_group_desc *desc);
1630extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1631extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1632						ext4_group_t, int);
1633/* inode.c */
1634struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1635						ext4_lblk_t, int, int *);
1636struct buffer_head *ext4_bread(handle_t *, struct inode *,
1637						ext4_lblk_t, int, int *);
1638int ext4_get_block(struct inode *inode, sector_t iblock,
1639				struct buffer_head *bh_result, int create);
1640
1641extern struct inode *ext4_iget(struct super_block *, unsigned long);
1642extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1643extern int  ext4_setattr(struct dentry *, struct iattr *);
1644extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1645				struct kstat *stat);
1646extern void ext4_evict_inode(struct inode *);
1647extern void ext4_clear_inode(struct inode *);
1648extern int  ext4_sync_inode(handle_t *, struct inode *);
1649extern void ext4_dirty_inode(struct inode *);
1650extern int ext4_change_inode_journal_flag(struct inode *, int);
1651extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1652extern int ext4_can_truncate(struct inode *inode);
1653extern void ext4_truncate(struct inode *);
1654extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1655extern void ext4_set_inode_flags(struct inode *);
1656extern void ext4_get_inode_flags(struct ext4_inode_info *);
1657extern int ext4_alloc_da_blocks(struct inode *inode);
1658extern void ext4_set_aops(struct inode *inode);
1659extern int ext4_writepage_trans_blocks(struct inode *);
1660extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1661extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1662extern int ext4_block_truncate_page(handle_t *handle,
1663		struct address_space *mapping, loff_t from);
1664extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1665extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1666extern int flush_completed_IO(struct inode *inode);
1667extern void ext4_da_update_reserve_space(struct inode *inode,
1668					int used, int quota_claim);
1669/* ioctl.c */
1670extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1671extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1672
1673/* migrate.c */
1674extern int ext4_ext_migrate(struct inode *);
1675
1676/* namei.c */
1677extern int ext4_orphan_add(handle_t *, struct inode *);
1678extern int ext4_orphan_del(handle_t *, struct inode *);
1679extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1680				__u32 start_minor_hash, __u32 *next_hash);
1681
1682/* resize.c */
1683extern int ext4_group_add(struct super_block *sb,
1684				struct ext4_new_group_data *input);
1685extern int ext4_group_extend(struct super_block *sb,
1686				struct ext4_super_block *es,
1687				ext4_fsblk_t n_blocks_count);
1688
1689/* super.c */
1690extern void __ext4_error(struct super_block *, const char *, unsigned int,
1691			 const char *, ...)
1692	__attribute__ ((format (printf, 4, 5)));
1693#define ext4_error(sb, message...)	__ext4_error(sb, __func__,	\
1694						     __LINE__, ## message)
1695extern void ext4_error_inode(struct inode *, const char *, unsigned int,
1696			     ext4_fsblk_t, const char *, ...)
1697	__attribute__ ((format (printf, 5, 6)));
1698extern void ext4_error_file(struct file *, const char *, unsigned int,
1699			    const char *, ...)
1700	__attribute__ ((format (printf, 4, 5)));
1701extern void __ext4_std_error(struct super_block *, const char *,
1702			     unsigned int, int);
1703extern void __ext4_abort(struct super_block *, const char *, unsigned int,
1704		       const char *, ...)
1705	__attribute__ ((format (printf, 4, 5)));
1706#define ext4_abort(sb, message...)	__ext4_abort(sb, __func__, \
1707						       __LINE__, ## message)
1708extern void __ext4_warning(struct super_block *, const char *, unsigned int,
1709			  const char *, ...)
1710	__attribute__ ((format (printf, 4, 5)));
1711#define ext4_warning(sb, message...)	__ext4_warning(sb, __func__, \
1712						       __LINE__, ## message)
1713extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1714	__attribute__ ((format (printf, 3, 4)));
1715extern void __ext4_grp_locked_error(const char *, unsigned int, \
1716				    struct super_block *, ext4_group_t, \
1717				    unsigned long, ext4_fsblk_t, \
1718				    const char *, ...)
1719	__attribute__ ((format (printf, 7, 8)));
1720#define ext4_grp_locked_error(sb, grp, message...) \
1721	__ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1722extern void ext4_update_dynamic_rev(struct super_block *sb);
1723extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1724					__u32 compat);
1725extern int ext4_update_rocompat_feature(handle_t *handle,
1726					struct super_block *sb,	__u32 rocompat);
1727extern int ext4_update_incompat_feature(handle_t *handle,
1728					struct super_block *sb,	__u32 incompat);
1729extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1730				      struct ext4_group_desc *bg);
1731extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1732				      struct ext4_group_desc *bg);
1733extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1734				     struct ext4_group_desc *bg);
1735extern __u32 ext4_free_blks_count(struct super_block *sb,
1736				struct ext4_group_desc *bg);
1737extern __u32 ext4_free_inodes_count(struct super_block *sb,
1738				 struct ext4_group_desc *bg);
1739extern __u32 ext4_used_dirs_count(struct super_block *sb,
1740				struct ext4_group_desc *bg);
1741extern __u32 ext4_itable_unused_count(struct super_block *sb,
1742				   struct ext4_group_desc *bg);
1743extern void ext4_block_bitmap_set(struct super_block *sb,
1744				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1745extern void ext4_inode_bitmap_set(struct super_block *sb,
1746				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1747extern void ext4_inode_table_set(struct super_block *sb,
1748				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
1749extern void ext4_free_blks_set(struct super_block *sb,
1750			       struct ext4_group_desc *bg, __u32 count);
1751extern void ext4_free_inodes_set(struct super_block *sb,
1752				struct ext4_group_desc *bg, __u32 count);
1753extern void ext4_used_dirs_set(struct super_block *sb,
1754				struct ext4_group_desc *bg, __u32 count);
1755extern void ext4_itable_unused_set(struct super_block *sb,
1756				   struct ext4_group_desc *bg, __u32 count);
1757extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1758				   struct ext4_group_desc *gdp);
1759extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1760				       struct ext4_group_desc *gdp);
1761
1762static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1763{
1764	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1765		le32_to_cpu(es->s_blocks_count_lo);
1766}
1767
1768static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1769{
1770	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1771		le32_to_cpu(es->s_r_blocks_count_lo);
1772}
1773
1774static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1775{
1776	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1777		le32_to_cpu(es->s_free_blocks_count_lo);
1778}
1779
1780static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1781					 ext4_fsblk_t blk)
1782{
1783	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1784	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1785}
1786
1787static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1788					      ext4_fsblk_t blk)
1789{
1790	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1791	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1792}
1793
1794static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1795					   ext4_fsblk_t blk)
1796{
1797	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1798	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1799}
1800
1801static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1802{
1803	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1804		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1805			le32_to_cpu(raw_inode->i_size_lo);
1806	else
1807		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1808}
1809
1810static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1811{
1812	raw_inode->i_size_lo = cpu_to_le32(i_size);
1813	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1814}
1815
1816static inline
1817struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1818					    ext4_group_t group)
1819{
1820	 struct ext4_group_info ***grp_info;
1821	 long indexv, indexh;
1822	 grp_info = EXT4_SB(sb)->s_group_info;
1823	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1824	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1825	 return grp_info[indexv][indexh];
1826}
1827
1828/*
1829 * Reading s_groups_count requires using smp_rmb() afterwards.  See
1830 * the locking protocol documented in the comments of ext4_group_add()
1831 * in resize.c
1832 */
1833static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
1834{
1835	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
1836
1837	smp_rmb();
1838	return ngroups;
1839}
1840
1841static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1842					     ext4_group_t block_group)
1843{
1844	return block_group >> sbi->s_log_groups_per_flex;
1845}
1846
1847static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1848{
1849	return 1 << sbi->s_log_groups_per_flex;
1850}
1851
1852#define ext4_std_error(sb, errno)				\
1853do {								\
1854	if ((errno))						\
1855		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
1856} while (0)
1857
1858#ifdef CONFIG_SMP
1859/* Each CPU can accumulate percpu_counter_batch blocks in their local
1860 * counters. So we need to make sure we have free blocks more
1861 * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1862 */
1863#define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1864#else
1865#define EXT4_FREEBLOCKS_WATERMARK 0
1866#endif
1867
1868static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1869{
1870	down_write(&EXT4_I(inode)->i_data_sem);
1871	if (newsize > EXT4_I(inode)->i_disksize)
1872		EXT4_I(inode)->i_disksize = newsize;
1873	up_write(&EXT4_I(inode)->i_data_sem);
1874	return ;
1875}
1876
1877struct ext4_group_info {
1878	unsigned long   bb_state;
1879	struct rb_root  bb_free_root;
1880	ext4_grpblk_t	bb_first_free;	/* first free block */
1881	ext4_grpblk_t	bb_free;	/* total free blocks */
1882	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
1883	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
1884	struct          list_head bb_prealloc_list;
1885#ifdef DOUBLE_CHECK
1886	void            *bb_bitmap;
1887#endif
1888	struct rw_semaphore alloc_sem;
1889	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
1890					 * regions, index is order.
1891					 * bb_counters[3] = 5 means
1892					 * 5 free 8-block regions. */
1893};
1894
1895#define EXT4_GROUP_INFO_NEED_INIT_BIT	0
1896
1897#define EXT4_MB_GRP_NEED_INIT(grp)	\
1898	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1899
1900#define EXT4_MAX_CONTENTION		8
1901#define EXT4_CONTENTION_THRESHOLD	2
1902
1903static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
1904					      ext4_group_t group)
1905{
1906	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
1907}
1908
1909/*
1910 * Returns true if the filesystem is busy enough that attempts to
1911 * access the block group locks has run into contention.
1912 */
1913static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
1914{
1915	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
1916}
1917
1918static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1919{
1920	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
1921	if (spin_trylock(lock))
1922		/*
1923		 * We're able to grab the lock right away, so drop the
1924		 * lock contention counter.
1925		 */
1926		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
1927	else {
1928		/*
1929		 * The lock is busy, so bump the contention counter,
1930		 * and then wait on the spin lock.
1931		 */
1932		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
1933				  EXT4_MAX_CONTENTION);
1934		spin_lock(lock);
1935	}
1936}
1937
1938static inline void ext4_unlock_group(struct super_block *sb,
1939					ext4_group_t group)
1940{
1941	spin_unlock(ext4_group_lock_ptr(sb, group));
1942}
1943
1944static inline void ext4_mark_super_dirty(struct super_block *sb)
1945{
1946	if (EXT4_SB(sb)->s_journal == NULL)
1947		sb->s_dirt =1;
1948}
1949
1950/*
1951 * Inodes and files operations
1952 */
1953
1954/* dir.c */
1955extern const struct file_operations ext4_dir_operations;
1956
1957/* file.c */
1958extern const struct inode_operations ext4_file_inode_operations;
1959extern const struct file_operations ext4_file_operations;
1960
1961/* namei.c */
1962extern const struct inode_operations ext4_dir_inode_operations;
1963extern const struct inode_operations ext4_special_inode_operations;
1964extern struct dentry *ext4_get_parent(struct dentry *child);
1965
1966/* symlink.c */
1967extern const struct inode_operations ext4_symlink_inode_operations;
1968extern const struct inode_operations ext4_fast_symlink_inode_operations;
1969
1970/* block_validity */
1971extern void ext4_release_system_zone(struct super_block *sb);
1972extern int ext4_setup_system_zone(struct super_block *sb);
1973extern int __init init_ext4_system_zone(void);
1974extern void exit_ext4_system_zone(void);
1975extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
1976				 ext4_fsblk_t start_blk,
1977				 unsigned int count);
1978
1979/* extents.c */
1980extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1981extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1982extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1983				       int chunk);
1984extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
1985			       struct ext4_map_blocks *map, int flags);
1986extern void ext4_ext_truncate(struct inode *);
1987extern void ext4_ext_init(struct super_block *);
1988extern void ext4_ext_release(struct super_block *);
1989extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1990			  loff_t len);
1991extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
1992			  ssize_t len);
1993extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
1994			   struct ext4_map_blocks *map, int flags);
1995extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1996			__u64 start, __u64 len);
1997/* move_extent.c */
1998extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
1999			     __u64 start_orig, __u64 start_donor,
2000			     __u64 len, __u64 *moved_len);
2001
2002
2003/* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2004enum ext4_state_bits {
2005	BH_Uninit	/* blocks are allocated but uninitialized on disk */
2006	  = BH_JBDPrivateStart,
2007};
2008
2009BUFFER_FNS(Uninit, uninit)
2010TAS_BUFFER_FNS(Uninit, uninit)
2011
2012/*
2013 * Add new method to test wether block and inode bitmaps are properly
2014 * initialized. With uninit_bg reading the block from disk is not enough
2015 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2016 */
2017#define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2018
2019static inline int bitmap_uptodate(struct buffer_head *bh)
2020{
2021	return (buffer_uptodate(bh) &&
2022			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2023}
2024static inline void set_bitmap_uptodate(struct buffer_head *bh)
2025{
2026	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2027}
2028
2029#define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
2030
2031#endif	/* __KERNEL__ */
2032
2033#endif	/* _EXT4_H */
2034