xref: /linux/fs/ext4/ext4.h (revision b68fc09be48edbc47de1a0f3d42ef8adf6c0ac55)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/version.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #define __FS_HAS_ENCRYPTION IS_ENABLED(CONFIG_EXT4_FS_ENCRYPTION)
44 #include <linux/fscrypt.h>
45 
46 #include <linux/compiler.h>
47 
48 /* Until this gets included into linux/compiler-gcc.h */
49 #ifndef __nonstring
50 #if defined(GCC_VERSION) && (GCC_VERSION >= 80000)
51 #define __nonstring __attribute__((nonstring))
52 #else
53 #define __nonstring
54 #endif
55 #endif
56 
57 /*
58  * The fourth extended filesystem constants/structures
59  */
60 
61 /*
62  * with AGGRESSIVE_CHECK allocator runs consistency checks over
63  * structures. these checks slow things down a lot
64  */
65 #define AGGRESSIVE_CHECK__
66 
67 /*
68  * with DOUBLE_CHECK defined mballoc creates persistent in-core
69  * bitmaps, maintains and uses them to check for double allocations
70  */
71 #define DOUBLE_CHECK__
72 
73 /*
74  * Define EXT4FS_DEBUG to produce debug messages
75  */
76 #undef EXT4FS_DEBUG
77 
78 /*
79  * Debug code
80  */
81 #ifdef EXT4FS_DEBUG
82 #define ext4_debug(f, a...)						\
83 	do {								\
84 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
85 			__FILE__, __LINE__, __func__);			\
86 		printk(KERN_DEBUG f, ## a);				\
87 	} while (0)
88 #else
89 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
90 #endif
91 
92 /*
93  * Turn on EXT_DEBUG to get lots of info about extents operations.
94  */
95 #define EXT_DEBUG__
96 #ifdef EXT_DEBUG
97 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
98 #else
99 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
100 #endif
101 
102 /* data type for block offset of block group */
103 typedef int ext4_grpblk_t;
104 
105 /* data type for filesystem-wide blocks number */
106 typedef unsigned long long ext4_fsblk_t;
107 
108 /* data type for file logical block number */
109 typedef __u32 ext4_lblk_t;
110 
111 /* data type for block group number */
112 typedef unsigned int ext4_group_t;
113 
114 enum SHIFT_DIRECTION {
115 	SHIFT_LEFT = 0,
116 	SHIFT_RIGHT,
117 };
118 
119 /*
120  * Flags used in mballoc's allocation_context flags field.
121  *
122  * Also used to show what's going on for debugging purposes when the
123  * flag field is exported via the traceport interface
124  */
125 
126 /* prefer goal again. length */
127 #define EXT4_MB_HINT_MERGE		0x0001
128 /* blocks already reserved */
129 #define EXT4_MB_HINT_RESERVED		0x0002
130 /* metadata is being allocated */
131 #define EXT4_MB_HINT_METADATA		0x0004
132 /* first blocks in the file */
133 #define EXT4_MB_HINT_FIRST		0x0008
134 /* search for the best chunk */
135 #define EXT4_MB_HINT_BEST		0x0010
136 /* data is being allocated */
137 #define EXT4_MB_HINT_DATA		0x0020
138 /* don't preallocate (for tails) */
139 #define EXT4_MB_HINT_NOPREALLOC		0x0040
140 /* allocate for locality group */
141 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
142 /* allocate goal blocks or none */
143 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
144 /* goal is meaningful */
145 #define EXT4_MB_HINT_TRY_GOAL		0x0200
146 /* blocks already pre-reserved by delayed allocation */
147 #define EXT4_MB_DELALLOC_RESERVED	0x0400
148 /* We are doing stream allocation */
149 #define EXT4_MB_STREAM_ALLOC		0x0800
150 /* Use reserved root blocks if needed */
151 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
152 /* Use blocks from reserved pool */
153 #define EXT4_MB_USE_RESERVED		0x2000
154 
155 struct ext4_allocation_request {
156 	/* target inode for block we're allocating */
157 	struct inode *inode;
158 	/* how many blocks we want to allocate */
159 	unsigned int len;
160 	/* logical block in target inode */
161 	ext4_lblk_t logical;
162 	/* the closest logical allocated block to the left */
163 	ext4_lblk_t lleft;
164 	/* the closest logical allocated block to the right */
165 	ext4_lblk_t lright;
166 	/* phys. target (a hint) */
167 	ext4_fsblk_t goal;
168 	/* phys. block for the closest logical allocated block to the left */
169 	ext4_fsblk_t pleft;
170 	/* phys. block for the closest logical allocated block to the right */
171 	ext4_fsblk_t pright;
172 	/* flags. see above EXT4_MB_HINT_* */
173 	unsigned int flags;
174 };
175 
176 /*
177  * Logical to physical block mapping, used by ext4_map_blocks()
178  *
179  * This structure is used to pass requests into ext4_map_blocks() as
180  * well as to store the information returned by ext4_map_blocks().  It
181  * takes less room on the stack than a struct buffer_head.
182  */
183 #define EXT4_MAP_NEW		(1 << BH_New)
184 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
185 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
186 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
187 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
188 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
189 
190 struct ext4_map_blocks {
191 	ext4_fsblk_t m_pblk;
192 	ext4_lblk_t m_lblk;
193 	unsigned int m_len;
194 	unsigned int m_flags;
195 };
196 
197 /*
198  * Flags for ext4_io_end->flags
199  */
200 #define	EXT4_IO_END_UNWRITTEN	0x0001
201 
202 /*
203  * For converting unwritten extents on a work queue. 'handle' is used for
204  * buffered writeback.
205  */
206 typedef struct ext4_io_end {
207 	struct list_head	list;		/* per-file finished IO list */
208 	handle_t		*handle;	/* handle reserved for extent
209 						 * conversion */
210 	struct inode		*inode;		/* file being written to */
211 	struct bio		*bio;		/* Linked list of completed
212 						 * bios covering the extent */
213 	unsigned int		flag;		/* unwritten or not */
214 	atomic_t		count;		/* reference counter */
215 	loff_t			offset;		/* offset in the file */
216 	ssize_t			size;		/* size of the extent */
217 } ext4_io_end_t;
218 
219 struct ext4_io_submit {
220 	struct writeback_control *io_wbc;
221 	struct bio		*io_bio;
222 	ext4_io_end_t		*io_end;
223 	sector_t		io_next_block;
224 };
225 
226 /*
227  * Special inodes numbers
228  */
229 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
230 #define EXT4_ROOT_INO		 2	/* Root inode */
231 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
232 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
233 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
234 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
235 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
236 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
237 
238 /* First non-reserved inode for old ext4 filesystems */
239 #define EXT4_GOOD_OLD_FIRST_INO	11
240 
241 /*
242  * Maximal count of links to a file
243  */
244 #define EXT4_LINK_MAX		65000
245 
246 /*
247  * Macro-instructions used to manage several block sizes
248  */
249 #define EXT4_MIN_BLOCK_SIZE		1024
250 #define	EXT4_MAX_BLOCK_SIZE		65536
251 #define EXT4_MIN_BLOCK_LOG_SIZE		10
252 #define EXT4_MAX_BLOCK_LOG_SIZE		16
253 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
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 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
282 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
283 								  blkbits))
284 
285 /* Translate a block number to a cluster number */
286 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
287 /* Translate a cluster number to a block number */
288 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
289 /* Translate # of blks to # of clusters */
290 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
291 				 (sbi)->s_cluster_bits)
292 /* Mask out the low bits to get the starting block of the cluster */
293 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
294 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
295 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
296 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
297 /* Get the cluster offset */
298 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
299 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
300 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
301 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
302 
303 /*
304  * Structure of a blocks group descriptor
305  */
306 struct ext4_group_desc
307 {
308 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
309 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
310 	__le32	bg_inode_table_lo;	/* Inodes table block */
311 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
312 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
313 	__le16	bg_used_dirs_count_lo;	/* Directories count */
314 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
315 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
316 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
317 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
318 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
319 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
320 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
321 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
322 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
323 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
324 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
325 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
326 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
327 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
328 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
329 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
330 	__u32   bg_reserved;
331 };
332 
333 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
334 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
335 	 sizeof(__le16))
336 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
337 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
338 	 sizeof(__le16))
339 
340 /*
341  * Structure of a flex block group info
342  */
343 
344 struct flex_groups {
345 	atomic64_t	free_clusters;
346 	atomic_t	free_inodes;
347 	atomic_t	used_dirs;
348 };
349 
350 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
351 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
352 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
353 
354 /*
355  * Macro-instructions used to manage group descriptors
356  */
357 #define EXT4_MIN_DESC_SIZE		32
358 #define EXT4_MIN_DESC_SIZE_64BIT	64
359 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
360 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
361 #ifdef __KERNEL__
362 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
363 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
364 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
365 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
366 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
367 #else
368 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
369 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
370 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
371 #endif
372 
373 /*
374  * Constants relative to the data blocks
375  */
376 #define	EXT4_NDIR_BLOCKS		12
377 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
378 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
379 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
380 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
381 
382 /*
383  * Inode flags
384  */
385 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
386 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
387 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
388 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
389 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
390 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
391 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
392 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
393 /* Reserved for compression usage... */
394 #define EXT4_DIRTY_FL			0x00000100
395 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
396 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
397 	/* nb: was previously EXT2_ECOMPR_FL */
398 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
399 /* End compression flags --- maybe not all used */
400 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
401 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
402 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
403 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
404 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
405 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
406 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
407 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
408 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
409 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
410 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
411 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
412 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
413 
414 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
415 #define EXT4_FL_USER_MODIFIABLE		0x204BC0FF /* User modifiable flags */
416 
417 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
418 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
419 					 EXT4_IMMUTABLE_FL | \
420 					 EXT4_APPEND_FL | \
421 					 EXT4_NODUMP_FL | \
422 					 EXT4_NOATIME_FL | \
423 					 EXT4_PROJINHERIT_FL)
424 
425 /* Flags that should be inherited by new inodes from their parent. */
426 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
427 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
428 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
429 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
430 			   EXT4_PROJINHERIT_FL)
431 
432 /* Flags that are appropriate for regular files (all but dir-specific ones). */
433 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
434 
435 /* Flags that are appropriate for non-directories/regular files. */
436 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
437 
438 /* Mask out flags that are inappropriate for the given type of inode. */
439 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
440 {
441 	if (S_ISDIR(mode))
442 		return flags;
443 	else if (S_ISREG(mode))
444 		return flags & EXT4_REG_FLMASK;
445 	else
446 		return flags & EXT4_OTHER_FLMASK;
447 }
448 
449 /*
450  * Inode flags used for atomic set/get
451  */
452 enum {
453 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
454 	EXT4_INODE_UNRM		= 1,	/* Undelete */
455 	EXT4_INODE_COMPR	= 2,	/* Compress file */
456 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
457 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
458 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
459 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
460 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
461 /* Reserved for compression usage... */
462 	EXT4_INODE_DIRTY	= 8,
463 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
464 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
465 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
466 /* End compression flags --- maybe not all used */
467 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
468 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
469 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
470 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
471 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
472 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
473 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
474 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
475 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
476 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
477 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
478 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
479 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
480 };
481 
482 /*
483  * Since it's pretty easy to mix up bit numbers and hex values, we use a
484  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
485  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
486  * any extra space in the compiled kernel image, otherwise, the build will fail.
487  * It's important that these values are the same, since we are using
488  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
489  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
490  * values found in ext2, ext3 and ext4 filesystems, and of course the values
491  * defined in e2fsprogs.
492  *
493  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
494  */
495 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
496 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
497 
498 static inline void ext4_check_flag_values(void)
499 {
500 	CHECK_FLAG_VALUE(SECRM);
501 	CHECK_FLAG_VALUE(UNRM);
502 	CHECK_FLAG_VALUE(COMPR);
503 	CHECK_FLAG_VALUE(SYNC);
504 	CHECK_FLAG_VALUE(IMMUTABLE);
505 	CHECK_FLAG_VALUE(APPEND);
506 	CHECK_FLAG_VALUE(NODUMP);
507 	CHECK_FLAG_VALUE(NOATIME);
508 	CHECK_FLAG_VALUE(DIRTY);
509 	CHECK_FLAG_VALUE(COMPRBLK);
510 	CHECK_FLAG_VALUE(NOCOMPR);
511 	CHECK_FLAG_VALUE(ENCRYPT);
512 	CHECK_FLAG_VALUE(INDEX);
513 	CHECK_FLAG_VALUE(IMAGIC);
514 	CHECK_FLAG_VALUE(JOURNAL_DATA);
515 	CHECK_FLAG_VALUE(NOTAIL);
516 	CHECK_FLAG_VALUE(DIRSYNC);
517 	CHECK_FLAG_VALUE(TOPDIR);
518 	CHECK_FLAG_VALUE(HUGE_FILE);
519 	CHECK_FLAG_VALUE(EXTENTS);
520 	CHECK_FLAG_VALUE(EA_INODE);
521 	CHECK_FLAG_VALUE(EOFBLOCKS);
522 	CHECK_FLAG_VALUE(INLINE_DATA);
523 	CHECK_FLAG_VALUE(PROJINHERIT);
524 	CHECK_FLAG_VALUE(RESERVED);
525 }
526 
527 /* Used to pass group descriptor data when online resize is done */
528 struct ext4_new_group_input {
529 	__u32 group;		/* Group number for this data */
530 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
531 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
532 	__u64 inode_table;	/* Absolute block number of inode table start */
533 	__u32 blocks_count;	/* Total number of blocks in this group */
534 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
535 	__u16 unused;
536 };
537 
538 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
539 struct compat_ext4_new_group_input {
540 	u32 group;
541 	compat_u64 block_bitmap;
542 	compat_u64 inode_bitmap;
543 	compat_u64 inode_table;
544 	u32 blocks_count;
545 	u16 reserved_blocks;
546 	u16 unused;
547 };
548 #endif
549 
550 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
551 struct ext4_new_group_data {
552 	__u32 group;
553 	__u64 block_bitmap;
554 	__u64 inode_bitmap;
555 	__u64 inode_table;
556 	__u32 blocks_count;
557 	__u16 reserved_blocks;
558 	__u16 mdata_blocks;
559 	__u32 free_clusters_count;
560 };
561 
562 /* Indexes used to index group tables in ext4_new_group_data */
563 enum {
564 	BLOCK_BITMAP = 0,	/* block bitmap */
565 	INODE_BITMAP,		/* inode bitmap */
566 	INODE_TABLE,		/* inode tables */
567 	GROUP_TABLE_COUNT,
568 };
569 
570 /*
571  * Flags used by ext4_map_blocks()
572  */
573 	/* Allocate any needed blocks and/or convert an unwritten
574 	   extent to be an initialized ext4 */
575 #define EXT4_GET_BLOCKS_CREATE			0x0001
576 	/* Request the creation of an unwritten extent */
577 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
578 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
579 						 EXT4_GET_BLOCKS_CREATE)
580 	/* Caller is from the delayed allocation writeout path
581 	 * finally doing the actual allocation of delayed blocks */
582 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
583 	/* caller is from the direct IO path, request to creation of an
584 	unwritten extents if not allocated, split the unwritten
585 	extent if blocks has been preallocated already*/
586 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
587 #define EXT4_GET_BLOCKS_CONVERT			0x0010
588 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
589 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
590 	/* Convert extent to initialized after IO complete */
591 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
592 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
593 	/* Eventual metadata allocation (due to growing extent tree)
594 	 * should not fail, so try to use reserved blocks for that.*/
595 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
596 	/* Don't normalize allocation size (used for fallocate) */
597 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
598 	/* Request will not result in inode size update (user for fallocate) */
599 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
600 	/* Convert written extents to unwritten */
601 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
602 	/* Write zeros to newly created written extents */
603 #define EXT4_GET_BLOCKS_ZERO			0x0200
604 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
605 					EXT4_GET_BLOCKS_ZERO)
606 	/* Caller will submit data before dropping transaction handle. This
607 	 * allows jbd2 to avoid submitting data before commit. */
608 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
609 
610 /*
611  * The bit position of these flags must not overlap with any of the
612  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
613  * read_extent_tree_block(), ext4_split_extent_at(),
614  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
615  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
616  * caching the extents when reading from the extent tree while a
617  * truncate or punch hole operation is in progress.
618  */
619 #define EXT4_EX_NOCACHE				0x40000000
620 #define EXT4_EX_FORCE_CACHE			0x20000000
621 
622 /*
623  * Flags used by ext4_free_blocks
624  */
625 #define EXT4_FREE_BLOCKS_METADATA		0x0001
626 #define EXT4_FREE_BLOCKS_FORGET			0x0002
627 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
628 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
629 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
630 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
631 
632 /*
633  * ioctl commands
634  */
635 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
636 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
637 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
638 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
639 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
640 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
641 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
642 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
643 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
644 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
645 #define EXT4_IOC_MIGRATE		_IO('f', 9)
646  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
647  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
648 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
649 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
650 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
651 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
652 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
653 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
654 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
655 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
656 
657 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
658 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
659 
660 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
661 
662 /*
663  * Flags for going down operation
664  */
665 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
666 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
667 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
668 
669 
670 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
671 /*
672  * ioctl commands in 32 bit emulation
673  */
674 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
675 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
676 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
677 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
678 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
679 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
680 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
681 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
682 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
683 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
684 #endif
685 
686 /* Max physical block we can address w/o extents */
687 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
688 
689 /* Max logical block we can support */
690 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFF
691 
692 /*
693  * Structure of an inode on the disk
694  */
695 struct ext4_inode {
696 	__le16	i_mode;		/* File mode */
697 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
698 	__le32	i_size_lo;	/* Size in bytes */
699 	__le32	i_atime;	/* Access time */
700 	__le32	i_ctime;	/* Inode Change time */
701 	__le32	i_mtime;	/* Modification time */
702 	__le32	i_dtime;	/* Deletion Time */
703 	__le16	i_gid;		/* Low 16 bits of Group Id */
704 	__le16	i_links_count;	/* Links count */
705 	__le32	i_blocks_lo;	/* Blocks count */
706 	__le32	i_flags;	/* File flags */
707 	union {
708 		struct {
709 			__le32  l_i_version;
710 		} linux1;
711 		struct {
712 			__u32  h_i_translator;
713 		} hurd1;
714 		struct {
715 			__u32  m_i_reserved1;
716 		} masix1;
717 	} osd1;				/* OS dependent 1 */
718 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
719 	__le32	i_generation;	/* File version (for NFS) */
720 	__le32	i_file_acl_lo;	/* File ACL */
721 	__le32	i_size_high;
722 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
723 	union {
724 		struct {
725 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
726 			__le16	l_i_file_acl_high;
727 			__le16	l_i_uid_high;	/* these 2 fields */
728 			__le16	l_i_gid_high;	/* were reserved2[0] */
729 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
730 			__le16	l_i_reserved;
731 		} linux2;
732 		struct {
733 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
734 			__u16	h_i_mode_high;
735 			__u16	h_i_uid_high;
736 			__u16	h_i_gid_high;
737 			__u32	h_i_author;
738 		} hurd2;
739 		struct {
740 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
741 			__le16	m_i_file_acl_high;
742 			__u32	m_i_reserved2[2];
743 		} masix2;
744 	} osd2;				/* OS dependent 2 */
745 	__le16	i_extra_isize;
746 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
747 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
748 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
749 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
750 	__le32  i_crtime;       /* File Creation time */
751 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
752 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
753 	__le32	i_projid;	/* Project ID */
754 };
755 
756 struct move_extent {
757 	__u32 reserved;		/* should be zero */
758 	__u32 donor_fd;		/* donor file descriptor */
759 	__u64 orig_start;	/* logical start offset in block for orig */
760 	__u64 donor_start;	/* logical start offset in block for donor */
761 	__u64 len;		/* block length to be moved */
762 	__u64 moved_len;	/* moved block length */
763 };
764 
765 #define EXT4_EPOCH_BITS 2
766 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
767 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
768 
769 /*
770  * Extended fields will fit into an inode if the filesystem was formatted
771  * with large inodes (-I 256 or larger) and there are not currently any EAs
772  * consuming all of the available space. For new inodes we always reserve
773  * enough space for the kernel's known extended fields, but for inodes
774  * created with an old kernel this might not have been the case. None of
775  * the extended inode fields is critical for correct filesystem operation.
776  * This macro checks if a certain field fits in the inode. Note that
777  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
778  */
779 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
780 	((offsetof(typeof(*ext4_inode), field) +	\
781 	  sizeof((ext4_inode)->field))			\
782 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
783 	    (einode)->i_extra_isize))			\
784 
785 /*
786  * We use an encoding that preserves the times for extra epoch "00":
787  *
788  * extra  msb of                         adjust for signed
789  * epoch  32-bit                         32-bit tv_sec to
790  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
791  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
792  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
793  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
794  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
795  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
796  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
797  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
798  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
799  *
800  * Note that previous versions of the kernel on 64-bit systems would
801  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
802  * 1970.  e2fsck will correct this, assuming that it is run on the
803  * affected filesystem before 2242.
804  */
805 
806 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
807 {
808 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
809 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
810 }
811 
812 static inline void ext4_decode_extra_time(struct timespec64 *time,
813 					  __le32 extra)
814 {
815 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK))) {
816 
817 #if 1
818 		/* Handle legacy encoding of pre-1970 dates with epoch
819 		 * bits 1,1. (This backwards compatibility may be removed
820 		 * at the discretion of the ext4 developers.)
821 		 */
822 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
823 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
824 			extra_bits = 0;
825 		time->tv_sec += extra_bits << 32;
826 #else
827 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
828 #endif
829 	}
830 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
831 }
832 
833 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
834 do {										\
835 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);		\
836 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
837 		(raw_inode)->xtime ## _extra =					\
838 				ext4_encode_extra_time(&(inode)->xtime);	\
839 		}								\
840 } while (0)
841 
842 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
843 do {									       \
844 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
845 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
846 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
847 		(raw_inode)->xtime ## _extra =				       \
848 				ext4_encode_extra_time(&(einode)->xtime);      \
849 } while (0)
850 
851 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
852 do {										\
853 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
854 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
855 		ext4_decode_extra_time(&(inode)->xtime,				\
856 				       raw_inode->xtime ## _extra);		\
857 		}								\
858 	else									\
859 		(inode)->xtime.tv_nsec = 0;					\
860 } while (0)
861 
862 
863 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
864 do {									       \
865 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
866 		(einode)->xtime.tv_sec = 				       \
867 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
868 	else								       \
869 		(einode)->xtime.tv_sec = 0;				       \
870 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
871 		ext4_decode_extra_time(&(einode)->xtime,		       \
872 				       raw_inode->xtime ## _extra);	       \
873 	else								       \
874 		(einode)->xtime.tv_nsec = 0;				       \
875 } while (0)
876 
877 #define i_disk_version osd1.linux1.l_i_version
878 
879 #if defined(__KERNEL__) || defined(__linux__)
880 #define i_reserved1	osd1.linux1.l_i_reserved1
881 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
882 #define i_blocks_high	osd2.linux2.l_i_blocks_high
883 #define i_uid_low	i_uid
884 #define i_gid_low	i_gid
885 #define i_uid_high	osd2.linux2.l_i_uid_high
886 #define i_gid_high	osd2.linux2.l_i_gid_high
887 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
888 
889 #elif defined(__GNU__)
890 
891 #define i_translator	osd1.hurd1.h_i_translator
892 #define i_uid_high	osd2.hurd2.h_i_uid_high
893 #define i_gid_high	osd2.hurd2.h_i_gid_high
894 #define i_author	osd2.hurd2.h_i_author
895 
896 #elif defined(__masix__)
897 
898 #define i_reserved1	osd1.masix1.m_i_reserved1
899 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
900 #define i_reserved2	osd2.masix2.m_i_reserved2
901 
902 #endif /* defined(__KERNEL__) || defined(__linux__) */
903 
904 #include "extents_status.h"
905 
906 /*
907  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
908  *
909  * These are needed to avoid lockdep false positives when we need to
910  * allocate blocks to the quota inode during ext4_map_blocks(), while
911  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
912  * do quota tracking for the quota inode, this avoids deadlock (as
913  * well as infinite recursion, since it isn't turtles all the way
914  * down...)
915  *
916  *  I_DATA_SEM_NORMAL - Used for most inodes
917  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
918  *			  where the second inode has larger inode number
919  *			  than the first
920  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
921  */
922 enum {
923 	I_DATA_SEM_NORMAL = 0,
924 	I_DATA_SEM_OTHER,
925 	I_DATA_SEM_QUOTA,
926 };
927 
928 
929 /*
930  * fourth extended file system inode data in memory
931  */
932 struct ext4_inode_info {
933 	__le32	i_data[15];	/* unconverted */
934 	__u32	i_dtime;
935 	ext4_fsblk_t	i_file_acl;
936 
937 	/*
938 	 * i_block_group is the number of the block group which contains
939 	 * this file's inode.  Constant across the lifetime of the inode,
940 	 * it is used for making block allocation decisions - we try to
941 	 * place a file's data blocks near its inode block, and new inodes
942 	 * near to their parent directory's inode.
943 	 */
944 	ext4_group_t	i_block_group;
945 	ext4_lblk_t	i_dir_start_lookup;
946 #if (BITS_PER_LONG < 64)
947 	unsigned long	i_state_flags;		/* Dynamic state flags */
948 #endif
949 	unsigned long	i_flags;
950 
951 	/*
952 	 * Extended attributes can be read independently of the main file
953 	 * data. Taking i_mutex even when reading would cause contention
954 	 * between readers of EAs and writers of regular file data, so
955 	 * instead we synchronize on xattr_sem when reading or changing
956 	 * EAs.
957 	 */
958 	struct rw_semaphore xattr_sem;
959 
960 	struct list_head i_orphan;	/* unlinked but open inodes */
961 
962 	/*
963 	 * i_disksize keeps track of what the inode size is ON DISK, not
964 	 * in memory.  During truncate, i_size is set to the new size by
965 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
966 	 * set i_disksize to 0 until the truncate is actually under way.
967 	 *
968 	 * The intent is that i_disksize always represents the blocks which
969 	 * are used by this file.  This allows recovery to restart truncate
970 	 * on orphans if we crash during truncate.  We actually write i_disksize
971 	 * into the on-disk inode when writing inodes out, instead of i_size.
972 	 *
973 	 * The only time when i_disksize and i_size may be different is when
974 	 * a truncate is in progress.  The only things which change i_disksize
975 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
976 	 */
977 	loff_t	i_disksize;
978 
979 	/*
980 	 * i_data_sem is for serialising ext4_truncate() against
981 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
982 	 * data tree are chopped off during truncate. We can't do that in
983 	 * ext4 because whenever we perform intermediate commits during
984 	 * truncate, the inode and all the metadata blocks *must* be in a
985 	 * consistent state which allows truncation of the orphans to restart
986 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
987 	 * by other means, so we have i_data_sem.
988 	 */
989 	struct rw_semaphore i_data_sem;
990 	/*
991 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
992 	 * operations. We have to make sure that new page cannot be faulted in
993 	 * a section of the inode that is being punched. We cannot easily use
994 	 * i_data_sem for this since we need protection for the whole punch
995 	 * operation and i_data_sem ranks below transaction start so we have
996 	 * to occasionally drop it.
997 	 */
998 	struct rw_semaphore i_mmap_sem;
999 	struct inode vfs_inode;
1000 	struct jbd2_inode *jinode;
1001 
1002 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1003 
1004 	/*
1005 	 * File creation time. Its function is same as that of
1006 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1007 	 */
1008 	struct timespec64 i_crtime;
1009 
1010 	/* mballoc */
1011 	struct list_head i_prealloc_list;
1012 	spinlock_t i_prealloc_lock;
1013 
1014 	/* extents status tree */
1015 	struct ext4_es_tree i_es_tree;
1016 	rwlock_t i_es_lock;
1017 	struct list_head i_es_list;
1018 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1019 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1020 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1021 					   extents to shrink. Protected by
1022 					   i_es_lock  */
1023 
1024 	/* ialloc */
1025 	ext4_group_t	i_last_alloc_group;
1026 
1027 	/* allocation reservation info for delalloc */
1028 	/* In case of bigalloc, this refer to clusters rather than blocks */
1029 	unsigned int i_reserved_data_blocks;
1030 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1031 	int i_da_metadata_calc_len;
1032 
1033 	/* on-disk additional length */
1034 	__u16 i_extra_isize;
1035 
1036 	/* Indicate the inline data space. */
1037 	u16 i_inline_off;
1038 	u16 i_inline_size;
1039 
1040 #ifdef CONFIG_QUOTA
1041 	/* quota space reservation, managed internally by quota code */
1042 	qsize_t i_reserved_quota;
1043 #endif
1044 
1045 	/* Lock protecting lists below */
1046 	spinlock_t i_completed_io_lock;
1047 	/*
1048 	 * Completed IOs that need unwritten extents handling and have
1049 	 * transaction reserved
1050 	 */
1051 	struct list_head i_rsv_conversion_list;
1052 	struct work_struct i_rsv_conversion_work;
1053 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1054 
1055 	spinlock_t i_block_reservation_lock;
1056 
1057 	/*
1058 	 * Transactions that contain inode's metadata needed to complete
1059 	 * fsync and fdatasync, respectively.
1060 	 */
1061 	tid_t i_sync_tid;
1062 	tid_t i_datasync_tid;
1063 
1064 #ifdef CONFIG_QUOTA
1065 	struct dquot *i_dquot[MAXQUOTAS];
1066 #endif
1067 
1068 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1069 	__u32 i_csum_seed;
1070 
1071 	kprojid_t i_projid;
1072 };
1073 
1074 /*
1075  * File system states
1076  */
1077 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1078 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1079 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1080 
1081 /*
1082  * Misc. filesystem flags
1083  */
1084 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1085 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1086 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1087 
1088 /*
1089  * Mount flags set via mount options or defaults
1090  */
1091 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1092 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1093 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1094 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1095 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1096 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1097 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1098 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1099 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1100 #ifdef CONFIG_FS_DAX
1101 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1102 #else
1103 #define EXT4_MOUNT_DAX			0
1104 #endif
1105 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1106 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1107 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1108 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1109 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1110 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1111 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1112 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1113 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1114 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1115 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1116 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1117 						 * enable enforcement for hidden
1118 						 * quota files */
1119 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1120 						  * enforcement for hidden quota
1121 						  * files */
1122 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1123 						  * enforcement */
1124 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1125 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1126 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1127 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1128 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1129 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1130 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1131 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1132 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1133 
1134 /*
1135  * Mount flags set either automatically (could not be set by mount option)
1136  * based on per file system feature or property or in special cases such as
1137  * distinguishing between explicit mount option definition and default.
1138  */
1139 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1140 						      specified delalloc */
1141 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1142 						      size of blocksize * 8
1143 						      blocks */
1144 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1145 						      file systems */
1146 
1147 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1148 						specified journal checksum */
1149 
1150 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1151 						~EXT4_MOUNT_##opt
1152 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1153 						EXT4_MOUNT_##opt
1154 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1155 					 EXT4_MOUNT_##opt)
1156 
1157 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1158 						~EXT4_MOUNT2_##opt
1159 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1160 						EXT4_MOUNT2_##opt
1161 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1162 					 EXT4_MOUNT2_##opt)
1163 
1164 #define ext4_test_and_set_bit		__test_and_set_bit_le
1165 #define ext4_set_bit			__set_bit_le
1166 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1167 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1168 #define ext4_clear_bit			__clear_bit_le
1169 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1170 #define ext4_test_bit			test_bit_le
1171 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1172 #define ext4_find_next_bit		find_next_bit_le
1173 
1174 extern void ext4_set_bits(void *bm, int cur, int len);
1175 
1176 /*
1177  * Maximal mount counts between two filesystem checks
1178  */
1179 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1180 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1181 
1182 /*
1183  * Behaviour when detecting errors
1184  */
1185 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1186 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1187 #define EXT4_ERRORS_PANIC		3	/* Panic */
1188 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1189 
1190 /* Metadata checksum algorithm codes */
1191 #define EXT4_CRC32C_CHKSUM		1
1192 
1193 /*
1194  * Structure of the super block
1195  */
1196 struct ext4_super_block {
1197 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1198 	__le32	s_blocks_count_lo;	/* Blocks count */
1199 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1200 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1201 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1202 	__le32	s_first_data_block;	/* First Data Block */
1203 	__le32	s_log_block_size;	/* Block size */
1204 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1205 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1206 	__le32	s_clusters_per_group;	/* # Clusters per group */
1207 	__le32	s_inodes_per_group;	/* # Inodes per group */
1208 	__le32	s_mtime;		/* Mount time */
1209 /*30*/	__le32	s_wtime;		/* Write time */
1210 	__le16	s_mnt_count;		/* Mount count */
1211 	__le16	s_max_mnt_count;	/* Maximal mount count */
1212 	__le16	s_magic;		/* Magic signature */
1213 	__le16	s_state;		/* File system state */
1214 	__le16	s_errors;		/* Behaviour when detecting errors */
1215 	__le16	s_minor_rev_level;	/* minor revision level */
1216 /*40*/	__le32	s_lastcheck;		/* time of last check */
1217 	__le32	s_checkinterval;	/* max. time between checks */
1218 	__le32	s_creator_os;		/* OS */
1219 	__le32	s_rev_level;		/* Revision level */
1220 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1221 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1222 	/*
1223 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1224 	 *
1225 	 * Note: the difference between the compatible feature set and
1226 	 * the incompatible feature set is that if there is a bit set
1227 	 * in the incompatible feature set that the kernel doesn't
1228 	 * know about, it should refuse to mount the filesystem.
1229 	 *
1230 	 * e2fsck's requirements are more strict; if it doesn't know
1231 	 * about a feature in either the compatible or incompatible
1232 	 * feature set, it must abort and not try to meddle with
1233 	 * things it doesn't understand...
1234 	 */
1235 	__le32	s_first_ino;		/* First non-reserved inode */
1236 	__le16  s_inode_size;		/* size of inode structure */
1237 	__le16	s_block_group_nr;	/* block group # of this superblock */
1238 	__le32	s_feature_compat;	/* compatible feature set */
1239 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1240 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1241 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1242 /*78*/	char	s_volume_name[16];	/* volume name */
1243 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1244 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1245 	/*
1246 	 * Performance hints.  Directory preallocation should only
1247 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1248 	 */
1249 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1250 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1251 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1252 	/*
1253 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1254 	 */
1255 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1256 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1257 	__le32	s_journal_dev;		/* device number of journal file */
1258 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1259 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1260 	__u8	s_def_hash_version;	/* Default hash version to use */
1261 	__u8	s_jnl_backup_type;
1262 	__le16  s_desc_size;		/* size of group descriptor */
1263 /*100*/	__le32	s_default_mount_opts;
1264 	__le32	s_first_meta_bg;	/* First metablock block group */
1265 	__le32	s_mkfs_time;		/* When the filesystem was created */
1266 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1267 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1268 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1269 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1270 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1271 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1272 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1273 	__le32	s_flags;		/* Miscellaneous flags */
1274 	__le16  s_raid_stride;		/* RAID stride */
1275 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1276 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1277 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1278 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1279 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1280 	__u8	s_encryption_level;	/* versioning level for encryption */
1281 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1282 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1283 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1284 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1285 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1286 					      snapshot's future use */
1287 	__le32	s_snapshot_list;	/* inode number of the head of the
1288 					   on-disk snapshot list */
1289 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1290 	__le32	s_error_count;		/* number of fs errors */
1291 	__le32	s_first_error_time;	/* first time an error happened */
1292 	__le32	s_first_error_ino;	/* inode involved in first error */
1293 	__le64	s_first_error_block;	/* block involved of first error */
1294 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1295 	__le32	s_first_error_line;	/* line number where error happened */
1296 	__le32	s_last_error_time;	/* most recent time of an error */
1297 	__le32	s_last_error_ino;	/* inode involved in last error */
1298 	__le32	s_last_error_line;	/* line number where error happened */
1299 	__le64	s_last_error_block;	/* block involved of last error */
1300 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1301 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1302 	__u8	s_mount_opts[64];
1303 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1304 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1305 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1306 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1307 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1308 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1309 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1310 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1311 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1312 	__u8	s_wtime_hi;
1313 	__u8	s_mtime_hi;
1314 	__u8	s_mkfs_time_hi;
1315 	__u8	s_lastcheck_hi;
1316 	__u8	s_first_error_time_hi;
1317 	__u8	s_last_error_time_hi;
1318 	__u8	s_pad[2];
1319 	__le32	s_reserved[96];		/* Padding to the end of the block */
1320 	__le32	s_checksum;		/* crc32c(superblock) */
1321 };
1322 
1323 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1324 
1325 #ifdef __KERNEL__
1326 
1327 /*
1328  * run-time mount flags
1329  */
1330 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1331 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1332 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1333 
1334 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1335 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1336 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1337 #else
1338 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1339 #endif
1340 
1341 /* Number of quota types we support */
1342 #define EXT4_MAXQUOTAS 3
1343 
1344 /*
1345  * fourth extended-fs super-block data in memory
1346  */
1347 struct ext4_sb_info {
1348 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1349 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1350 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1351 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1352 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1353 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1354 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1355 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1356 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1357 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1358 	unsigned long s_overhead;  /* # of fs overhead clusters */
1359 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1360 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1361 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1362 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1363 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1364 	struct buffer_head **s_group_desc;
1365 	unsigned int s_mount_opt;
1366 	unsigned int s_mount_opt2;
1367 	unsigned int s_mount_flags;
1368 	unsigned int s_def_mount_opt;
1369 	ext4_fsblk_t s_sb_block;
1370 	atomic64_t s_resv_clusters;
1371 	kuid_t s_resuid;
1372 	kgid_t s_resgid;
1373 	unsigned short s_mount_state;
1374 	unsigned short s_pad;
1375 	int s_addr_per_block_bits;
1376 	int s_desc_per_block_bits;
1377 	int s_inode_size;
1378 	int s_first_ino;
1379 	unsigned int s_inode_readahead_blks;
1380 	unsigned int s_inode_goal;
1381 	u32 s_hash_seed[4];
1382 	int s_def_hash_version;
1383 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1384 	struct percpu_counter s_freeclusters_counter;
1385 	struct percpu_counter s_freeinodes_counter;
1386 	struct percpu_counter s_dirs_counter;
1387 	struct percpu_counter s_dirtyclusters_counter;
1388 	struct blockgroup_lock *s_blockgroup_lock;
1389 	struct proc_dir_entry *s_proc;
1390 	struct kobject s_kobj;
1391 	struct completion s_kobj_unregister;
1392 	struct super_block *s_sb;
1393 
1394 	/* Journaling */
1395 	struct journal_s *s_journal;
1396 	struct list_head s_orphan;
1397 	struct mutex s_orphan_lock;
1398 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1399 	unsigned long s_commit_interval;
1400 	u32 s_max_batch_time;
1401 	u32 s_min_batch_time;
1402 	struct block_device *journal_bdev;
1403 #ifdef CONFIG_QUOTA
1404 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1405 	int s_jquota_fmt;			/* Format of quota to use */
1406 #endif
1407 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1408 	struct rb_root system_blks;
1409 
1410 #ifdef EXTENTS_STATS
1411 	/* ext4 extents stats */
1412 	unsigned long s_ext_min;
1413 	unsigned long s_ext_max;
1414 	unsigned long s_depth_max;
1415 	spinlock_t s_ext_stats_lock;
1416 	unsigned long s_ext_blocks;
1417 	unsigned long s_ext_extents;
1418 #endif
1419 
1420 	/* for buddy allocator */
1421 	struct ext4_group_info ***s_group_info;
1422 	struct inode *s_buddy_cache;
1423 	spinlock_t s_md_lock;
1424 	unsigned short *s_mb_offsets;
1425 	unsigned int *s_mb_maxs;
1426 	unsigned int s_group_info_size;
1427 	unsigned int s_mb_free_pending;
1428 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1429 						   after commit completed */
1430 
1431 	/* tunables */
1432 	unsigned long s_stripe;
1433 	unsigned int s_mb_stream_request;
1434 	unsigned int s_mb_max_to_scan;
1435 	unsigned int s_mb_min_to_scan;
1436 	unsigned int s_mb_stats;
1437 	unsigned int s_mb_order2_reqs;
1438 	unsigned int s_mb_group_prealloc;
1439 	unsigned int s_max_dir_size_kb;
1440 	/* where last allocation was done - for stream allocation */
1441 	unsigned long s_mb_last_group;
1442 	unsigned long s_mb_last_start;
1443 
1444 	/* stats for buddy allocator */
1445 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1446 	atomic_t s_bal_success;	/* we found long enough chunks */
1447 	atomic_t s_bal_allocated;	/* in blocks */
1448 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1449 	atomic_t s_bal_goals;	/* goal hits */
1450 	atomic_t s_bal_breaks;	/* too long searches */
1451 	atomic_t s_bal_2orders;	/* 2^order hits */
1452 	spinlock_t s_bal_lock;
1453 	unsigned long s_mb_buddies_generated;
1454 	unsigned long long s_mb_generation_time;
1455 	atomic_t s_mb_lost_chunks;
1456 	atomic_t s_mb_preallocated;
1457 	atomic_t s_mb_discarded;
1458 	atomic_t s_lock_busy;
1459 
1460 	/* locality groups */
1461 	struct ext4_locality_group __percpu *s_locality_groups;
1462 
1463 	/* for write statistics */
1464 	unsigned long s_sectors_written_start;
1465 	u64 s_kbytes_written;
1466 
1467 	/* the size of zero-out chunk */
1468 	unsigned int s_extent_max_zeroout_kb;
1469 
1470 	unsigned int s_log_groups_per_flex;
1471 	struct flex_groups *s_flex_groups;
1472 	ext4_group_t s_flex_groups_allocated;
1473 
1474 	/* workqueue for reserved extent conversions (buffered io) */
1475 	struct workqueue_struct *rsv_conversion_wq;
1476 
1477 	/* timer for periodic error stats printing */
1478 	struct timer_list s_err_report;
1479 
1480 	/* Lazy inode table initialization info */
1481 	struct ext4_li_request *s_li_request;
1482 	/* Wait multiplier for lazy initialization thread */
1483 	unsigned int s_li_wait_mult;
1484 
1485 	/* Kernel thread for multiple mount protection */
1486 	struct task_struct *s_mmp_tsk;
1487 
1488 	/* record the last minlen when FITRIM is called. */
1489 	atomic_t s_last_trim_minblks;
1490 
1491 	/* Reference to checksum algorithm driver via cryptoapi */
1492 	struct crypto_shash *s_chksum_driver;
1493 
1494 	/* Precomputed FS UUID checksum for seeding other checksums */
1495 	__u32 s_csum_seed;
1496 
1497 	/* Reclaim extents from extent status tree */
1498 	struct shrinker s_es_shrinker;
1499 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1500 	long s_es_nr_inode;
1501 	struct ext4_es_stats s_es_stats;
1502 	struct mb_cache *s_ea_block_cache;
1503 	struct mb_cache *s_ea_inode_cache;
1504 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1505 
1506 	/* Ratelimit ext4 messages. */
1507 	struct ratelimit_state s_err_ratelimit_state;
1508 	struct ratelimit_state s_warning_ratelimit_state;
1509 	struct ratelimit_state s_msg_ratelimit_state;
1510 
1511 	/* Barrier between changing inodes' journal flags and writepages ops. */
1512 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1513 	struct dax_device *s_daxdev;
1514 };
1515 
1516 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1517 {
1518 	return sb->s_fs_info;
1519 }
1520 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1521 {
1522 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1523 }
1524 
1525 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1526 {
1527 	return ino == EXT4_ROOT_INO ||
1528 		(ino >= EXT4_FIRST_INO(sb) &&
1529 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1530 }
1531 
1532 /*
1533  * Inode dynamic state flags
1534  */
1535 enum {
1536 	EXT4_STATE_JDATA,		/* journaled data exists */
1537 	EXT4_STATE_NEW,			/* inode is newly created */
1538 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1539 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1540 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1541 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1542 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1543 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1544 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1545 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1546 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1547 };
1548 
1549 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1550 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1551 {									\
1552 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1553 }									\
1554 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1555 {									\
1556 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1557 }									\
1558 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1559 {									\
1560 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1561 }
1562 
1563 /* Add these declarations here only so that these functions can be
1564  * found by name.  Otherwise, they are very hard to locate. */
1565 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1566 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1567 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1568 EXT4_INODE_BIT_FNS(flag, flags, 0)
1569 
1570 /* Add these declarations here only so that these functions can be
1571  * found by name.  Otherwise, they are very hard to locate. */
1572 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1573 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1574 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1575 #if (BITS_PER_LONG < 64)
1576 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1577 
1578 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1579 {
1580 	(ei)->i_state_flags = 0;
1581 }
1582 #else
1583 EXT4_INODE_BIT_FNS(state, flags, 32)
1584 
1585 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1586 {
1587 	/* We depend on the fact that callers will set i_flags */
1588 }
1589 #endif
1590 #else
1591 /* Assume that user mode programs are passing in an ext4fs superblock, not
1592  * a kernel struct super_block.  This will allow us to call the feature-test
1593  * macros from user land. */
1594 #define EXT4_SB(sb)	(sb)
1595 #endif
1596 
1597 /*
1598  * Returns true if the inode is inode is encrypted
1599  */
1600 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1601 
1602 /*
1603  * Codes for operating systems
1604  */
1605 #define EXT4_OS_LINUX		0
1606 #define EXT4_OS_HURD		1
1607 #define EXT4_OS_MASIX		2
1608 #define EXT4_OS_FREEBSD		3
1609 #define EXT4_OS_LITES		4
1610 
1611 /*
1612  * Revision levels
1613  */
1614 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1615 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1616 
1617 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1618 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1619 
1620 #define EXT4_GOOD_OLD_INODE_SIZE 128
1621 
1622 /*
1623  * Feature set definitions
1624  */
1625 
1626 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1627 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1628 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1629 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1630 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1631 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1632 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1633 
1634 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1635 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1636 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1637 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1638 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1639 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1640 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1641 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1642 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1643 /*
1644  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1645  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1646  * all other data structures' checksums.  However, the METADATA_CSUM and
1647  * GDT_CSUM bits are mutually exclusive.
1648  */
1649 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1650 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1651 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1652 
1653 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1654 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1655 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1656 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1657 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1658 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1659 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1660 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1661 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1662 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1663 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1664 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1665 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1666 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1667 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1668 
1669 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1670 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1671 { \
1672 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1673 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1674 } \
1675 static inline void ext4_set_feature_##name(struct super_block *sb) \
1676 { \
1677 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1678 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1679 } \
1680 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1681 { \
1682 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1683 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1684 }
1685 
1686 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1687 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1688 { \
1689 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1690 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1691 } \
1692 static inline void ext4_set_feature_##name(struct super_block *sb) \
1693 { \
1694 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1695 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1696 } \
1697 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1698 { \
1699 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1700 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1701 }
1702 
1703 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1704 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1705 { \
1706 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1707 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1708 } \
1709 static inline void ext4_set_feature_##name(struct super_block *sb) \
1710 { \
1711 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1712 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1713 } \
1714 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1715 { \
1716 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1717 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1718 }
1719 
1720 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1721 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1722 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1723 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1724 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1725 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1726 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1727 
1728 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1729 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1730 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1731 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1732 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1733 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1734 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1735 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1736 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1737 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1738 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1739 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1740 
1741 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1742 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1743 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1744 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1745 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1746 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1747 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1748 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1749 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1750 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1751 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1752 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1753 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1754 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1755 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1756 
1757 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1758 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1759 					 EXT4_FEATURE_INCOMPAT_META_BG)
1760 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1761 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1762 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1763 
1764 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1765 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1766 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1767 					 EXT4_FEATURE_INCOMPAT_META_BG)
1768 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1769 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1770 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1771 
1772 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1773 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1774 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1775 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1776 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1777 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1778 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1779 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1780 					 EXT4_FEATURE_INCOMPAT_MMP | \
1781 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1782 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1783 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1784 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1785 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1786 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1787 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1788 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1789 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1790 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1791 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1792 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1793 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1794 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1795 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1796 
1797 #define EXTN_FEATURE_FUNCS(ver) \
1798 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1799 { \
1800 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1801 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1802 } \
1803 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1804 { \
1805 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1806 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1807 } \
1808 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1809 { \
1810 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1811 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1812 }
1813 
1814 EXTN_FEATURE_FUNCS(2)
1815 EXTN_FEATURE_FUNCS(3)
1816 EXTN_FEATURE_FUNCS(4)
1817 
1818 static inline bool ext4_has_compat_features(struct super_block *sb)
1819 {
1820 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1821 }
1822 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1823 {
1824 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1825 }
1826 static inline bool ext4_has_incompat_features(struct super_block *sb)
1827 {
1828 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1829 }
1830 
1831 /*
1832  * Superblock flags
1833  */
1834 #define EXT4_FLAGS_RESIZING	0
1835 #define EXT4_FLAGS_SHUTDOWN	1
1836 
1837 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1838 {
1839 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1840 }
1841 
1842 
1843 /*
1844  * Default values for user and/or group using reserved blocks
1845  */
1846 #define	EXT4_DEF_RESUID		0
1847 #define	EXT4_DEF_RESGID		0
1848 
1849 /*
1850  * Default project ID
1851  */
1852 #define	EXT4_DEF_PROJID		0
1853 
1854 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1855 
1856 /*
1857  * Default mount options
1858  */
1859 #define EXT4_DEFM_DEBUG		0x0001
1860 #define EXT4_DEFM_BSDGROUPS	0x0002
1861 #define EXT4_DEFM_XATTR_USER	0x0004
1862 #define EXT4_DEFM_ACL		0x0008
1863 #define EXT4_DEFM_UID16		0x0010
1864 #define EXT4_DEFM_JMODE		0x0060
1865 #define EXT4_DEFM_JMODE_DATA	0x0020
1866 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1867 #define EXT4_DEFM_JMODE_WBACK	0x0060
1868 #define EXT4_DEFM_NOBARRIER	0x0100
1869 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1870 #define EXT4_DEFM_DISCARD	0x0400
1871 #define EXT4_DEFM_NODELALLOC	0x0800
1872 
1873 /*
1874  * Default journal batch times
1875  */
1876 #define EXT4_DEF_MIN_BATCH_TIME	0
1877 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1878 
1879 /*
1880  * Minimum number of groups in a flexgroup before we separate out
1881  * directories into the first block group of a flexgroup
1882  */
1883 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1884 
1885 /*
1886  * Structure of a directory entry
1887  */
1888 #define EXT4_NAME_LEN 255
1889 
1890 struct ext4_dir_entry {
1891 	__le32	inode;			/* Inode number */
1892 	__le16	rec_len;		/* Directory entry length */
1893 	__le16	name_len;		/* Name length */
1894 	char	name[EXT4_NAME_LEN];	/* File name */
1895 };
1896 
1897 /*
1898  * The new version of the directory entry.  Since EXT4 structures are
1899  * stored in intel byte order, and the name_len field could never be
1900  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1901  * file_type field.
1902  */
1903 struct ext4_dir_entry_2 {
1904 	__le32	inode;			/* Inode number */
1905 	__le16	rec_len;		/* Directory entry length */
1906 	__u8	name_len;		/* Name length */
1907 	__u8	file_type;
1908 	char	name[EXT4_NAME_LEN];	/* File name */
1909 };
1910 
1911 /*
1912  * This is a bogus directory entry at the end of each leaf block that
1913  * records checksums.
1914  */
1915 struct ext4_dir_entry_tail {
1916 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1917 	__le16	det_rec_len;		/* 12 */
1918 	__u8	det_reserved_zero2;	/* Zero name length */
1919 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1920 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1921 };
1922 
1923 #define EXT4_DIRENT_TAIL(block, blocksize) \
1924 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1925 					((blocksize) - \
1926 					 sizeof(struct ext4_dir_entry_tail))))
1927 
1928 /*
1929  * Ext4 directory file types.  Only the low 3 bits are used.  The
1930  * other bits are reserved for now.
1931  */
1932 #define EXT4_FT_UNKNOWN		0
1933 #define EXT4_FT_REG_FILE	1
1934 #define EXT4_FT_DIR		2
1935 #define EXT4_FT_CHRDEV		3
1936 #define EXT4_FT_BLKDEV		4
1937 #define EXT4_FT_FIFO		5
1938 #define EXT4_FT_SOCK		6
1939 #define EXT4_FT_SYMLINK		7
1940 
1941 #define EXT4_FT_MAX		8
1942 
1943 #define EXT4_FT_DIR_CSUM	0xDE
1944 
1945 /*
1946  * EXT4_DIR_PAD defines the directory entries boundaries
1947  *
1948  * NOTE: It must be a multiple of 4
1949  */
1950 #define EXT4_DIR_PAD			4
1951 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1952 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1953 					 ~EXT4_DIR_ROUND)
1954 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1955 
1956 /*
1957  * If we ever get support for fs block sizes > page_size, we'll need
1958  * to remove the #if statements in the next two functions...
1959  */
1960 static inline unsigned int
1961 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1962 {
1963 	unsigned len = le16_to_cpu(dlen);
1964 
1965 #if (PAGE_SIZE >= 65536)
1966 	if (len == EXT4_MAX_REC_LEN || len == 0)
1967 		return blocksize;
1968 	return (len & 65532) | ((len & 3) << 16);
1969 #else
1970 	return len;
1971 #endif
1972 }
1973 
1974 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1975 {
1976 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1977 		BUG();
1978 #if (PAGE_SIZE >= 65536)
1979 	if (len < 65536)
1980 		return cpu_to_le16(len);
1981 	if (len == blocksize) {
1982 		if (blocksize == 65536)
1983 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1984 		else
1985 			return cpu_to_le16(0);
1986 	}
1987 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1988 #else
1989 	return cpu_to_le16(len);
1990 #endif
1991 }
1992 
1993 /*
1994  * Hash Tree Directory indexing
1995  * (c) Daniel Phillips, 2001
1996  */
1997 
1998 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
1999 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2000 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2001 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2002 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2003 
2004 /* Legal values for the dx_root hash_version field: */
2005 
2006 #define DX_HASH_LEGACY			0
2007 #define DX_HASH_HALF_MD4		1
2008 #define DX_HASH_TEA			2
2009 #define DX_HASH_LEGACY_UNSIGNED		3
2010 #define DX_HASH_HALF_MD4_UNSIGNED	4
2011 #define DX_HASH_TEA_UNSIGNED		5
2012 
2013 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2014 			      const void *address, unsigned int length)
2015 {
2016 	struct {
2017 		struct shash_desc shash;
2018 		char ctx[4];
2019 	} desc;
2020 
2021 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2022 
2023 	desc.shash.tfm = sbi->s_chksum_driver;
2024 	desc.shash.flags = 0;
2025 	*(u32 *)desc.ctx = crc;
2026 
2027 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2028 
2029 	return *(u32 *)desc.ctx;
2030 }
2031 
2032 #ifdef __KERNEL__
2033 
2034 /* hash info structure used by the directory hash */
2035 struct dx_hash_info
2036 {
2037 	u32		hash;
2038 	u32		minor_hash;
2039 	int		hash_version;
2040 	u32		*seed;
2041 };
2042 
2043 
2044 /* 32 and 64 bit signed EOF for dx directories */
2045 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2046 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2047 
2048 
2049 /*
2050  * Control parameters used by ext4_htree_next_block
2051  */
2052 #define HASH_NB_ALWAYS		1
2053 
2054 struct ext4_filename {
2055 	const struct qstr *usr_fname;
2056 	struct fscrypt_str disk_name;
2057 	struct dx_hash_info hinfo;
2058 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2059 	struct fscrypt_str crypto_buf;
2060 #endif
2061 };
2062 
2063 #define fname_name(p) ((p)->disk_name.name)
2064 #define fname_len(p)  ((p)->disk_name.len)
2065 
2066 /*
2067  * Describe an inode's exact location on disk and in memory
2068  */
2069 struct ext4_iloc
2070 {
2071 	struct buffer_head *bh;
2072 	unsigned long offset;
2073 	ext4_group_t block_group;
2074 };
2075 
2076 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2077 {
2078 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2079 }
2080 
2081 static inline bool ext4_is_quota_file(struct inode *inode)
2082 {
2083 	return IS_NOQUOTA(inode) &&
2084 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2085 }
2086 
2087 /*
2088  * This structure is stuffed into the struct file's private_data field
2089  * for directories.  It is where we put information so that we can do
2090  * readdir operations in hash tree order.
2091  */
2092 struct dir_private_info {
2093 	struct rb_root	root;
2094 	struct rb_node	*curr_node;
2095 	struct fname	*extra_fname;
2096 	loff_t		last_pos;
2097 	__u32		curr_hash;
2098 	__u32		curr_minor_hash;
2099 	__u32		next_hash;
2100 };
2101 
2102 /* calculate the first block number of the group */
2103 static inline ext4_fsblk_t
2104 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2105 {
2106 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2107 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2108 }
2109 
2110 /*
2111  * Special error return code only used by dx_probe() and its callers.
2112  */
2113 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2114 
2115 /* htree levels for ext4 */
2116 #define	EXT4_HTREE_LEVEL_COMPAT	2
2117 #define	EXT4_HTREE_LEVEL	3
2118 
2119 static inline int ext4_dir_htree_level(struct super_block *sb)
2120 {
2121 	return ext4_has_feature_largedir(sb) ?
2122 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2123 }
2124 
2125 /*
2126  * Timeout and state flag for lazy initialization inode thread.
2127  */
2128 #define EXT4_DEF_LI_WAIT_MULT			10
2129 #define EXT4_DEF_LI_MAX_START_DELAY		5
2130 #define EXT4_LAZYINIT_QUIT			0x0001
2131 #define EXT4_LAZYINIT_RUNNING			0x0002
2132 
2133 /*
2134  * Lazy inode table initialization info
2135  */
2136 struct ext4_lazy_init {
2137 	unsigned long		li_state;
2138 	struct list_head	li_request_list;
2139 	struct mutex		li_list_mtx;
2140 };
2141 
2142 struct ext4_li_request {
2143 	struct super_block	*lr_super;
2144 	struct ext4_sb_info	*lr_sbi;
2145 	ext4_group_t		lr_next_group;
2146 	struct list_head	lr_request;
2147 	unsigned long		lr_next_sched;
2148 	unsigned long		lr_timeout;
2149 };
2150 
2151 struct ext4_features {
2152 	struct kobject f_kobj;
2153 	struct completion f_kobj_unregister;
2154 };
2155 
2156 /*
2157  * This structure will be used for multiple mount protection. It will be
2158  * written into the block number saved in the s_mmp_block field in the
2159  * superblock. Programs that check MMP should assume that if
2160  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2161  * to use the filesystem, regardless of how old the timestamp is.
2162  */
2163 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2164 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2165 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2166 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2167 
2168 struct mmp_struct {
2169 	__le32	mmp_magic;		/* Magic number for MMP */
2170 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2171 
2172 	/*
2173 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2174 	 * purposes and do not affect the correctness of the algorithm
2175 	 */
2176 	__le64	mmp_time;		/* Time last updated */
2177 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2178 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2179 
2180 	/*
2181 	 * mmp_check_interval is used to verify if the MMP block has been
2182 	 * updated on the block device. The value is updated based on the
2183 	 * maximum time to write the MMP block during an update cycle.
2184 	 */
2185 	__le16	mmp_check_interval;
2186 
2187 	__le16	mmp_pad1;
2188 	__le32	mmp_pad2[226];
2189 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2190 };
2191 
2192 /* arguments passed to the mmp thread */
2193 struct mmpd_data {
2194 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2195 	struct super_block *sb;  /* super block of the fs */
2196 };
2197 
2198 /*
2199  * Check interval multiplier
2200  * The MMP block is written every update interval and initially checked every
2201  * update interval x the multiplier (the value is then adapted based on the
2202  * write latency). The reason is that writes can be delayed under load and we
2203  * don't want readers to incorrectly assume that the filesystem is no longer
2204  * in use.
2205  */
2206 #define EXT4_MMP_CHECK_MULT		2UL
2207 
2208 /*
2209  * Minimum interval for MMP checking in seconds.
2210  */
2211 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2212 
2213 /*
2214  * Maximum interval for MMP checking in seconds.
2215  */
2216 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2217 
2218 /*
2219  * Function prototypes
2220  */
2221 
2222 /*
2223  * Ok, these declarations are also in <linux/kernel.h> but none of the
2224  * ext4 source programs needs to include it so they are duplicated here.
2225  */
2226 # define NORET_TYPE	/**/
2227 # define ATTRIB_NORET	__attribute__((noreturn))
2228 # define NORET_AND	noreturn,
2229 
2230 /* bitmap.c */
2231 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2232 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2233 				struct ext4_group_desc *gdp,
2234 				struct buffer_head *bh, int sz);
2235 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2236 				  struct ext4_group_desc *gdp,
2237 				  struct buffer_head *bh, int sz);
2238 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2239 				struct ext4_group_desc *gdp,
2240 				struct buffer_head *bh);
2241 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2242 				  struct ext4_group_desc *gdp,
2243 				  struct buffer_head *bh);
2244 
2245 /* balloc.c */
2246 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2247 					 ext4_fsblk_t blocknr,
2248 					 ext4_group_t *blockgrpp,
2249 					 ext4_grpblk_t *offsetp);
2250 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2251 					  ext4_fsblk_t block);
2252 
2253 extern unsigned int ext4_block_group(struct super_block *sb,
2254 			ext4_fsblk_t blocknr);
2255 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2256 			ext4_fsblk_t blocknr);
2257 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2258 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2259 			ext4_group_t group);
2260 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2261 					 ext4_fsblk_t goal,
2262 					 unsigned int flags,
2263 					 unsigned long *count,
2264 					 int *errp);
2265 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2266 				    s64 nclusters, unsigned int flags);
2267 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2268 extern void ext4_check_blocks_bitmap(struct super_block *);
2269 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2270 						    ext4_group_t block_group,
2271 						    struct buffer_head ** bh);
2272 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2273 
2274 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2275 						ext4_group_t block_group);
2276 extern int ext4_wait_block_bitmap(struct super_block *sb,
2277 				  ext4_group_t block_group,
2278 				  struct buffer_head *bh);
2279 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2280 						  ext4_group_t block_group);
2281 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2282 					      ext4_group_t block_group,
2283 					      struct ext4_group_desc *gdp);
2284 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2285 
2286 static inline bool ext4_encrypted_inode(struct inode *inode)
2287 {
2288 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2289 }
2290 
2291 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2292 static inline int ext4_fname_setup_filename(struct inode *dir,
2293 			const struct qstr *iname,
2294 			int lookup, struct ext4_filename *fname)
2295 {
2296 	struct fscrypt_name name;
2297 	int err;
2298 
2299 	memset(fname, 0, sizeof(struct ext4_filename));
2300 
2301 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2302 
2303 	fname->usr_fname = name.usr_fname;
2304 	fname->disk_name = name.disk_name;
2305 	fname->hinfo.hash = name.hash;
2306 	fname->hinfo.minor_hash = name.minor_hash;
2307 	fname->crypto_buf = name.crypto_buf;
2308 	return err;
2309 }
2310 
2311 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2312 {
2313 	struct fscrypt_name name;
2314 
2315 	name.crypto_buf = fname->crypto_buf;
2316 	fscrypt_free_filename(&name);
2317 
2318 	fname->crypto_buf.name = NULL;
2319 	fname->usr_fname = NULL;
2320 	fname->disk_name.name = NULL;
2321 }
2322 #else
2323 static inline int ext4_fname_setup_filename(struct inode *dir,
2324 		const struct qstr *iname,
2325 		int lookup, struct ext4_filename *fname)
2326 {
2327 	fname->usr_fname = iname;
2328 	fname->disk_name.name = (unsigned char *) iname->name;
2329 	fname->disk_name.len = iname->len;
2330 	return 0;
2331 }
2332 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2333 
2334 #endif
2335 
2336 /* dir.c */
2337 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2338 				  struct file *,
2339 				  struct ext4_dir_entry_2 *,
2340 				  struct buffer_head *, char *, int,
2341 				  unsigned int);
2342 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2343 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2344 					(de), (bh), (buf), (size), (offset)))
2345 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2346 				__u32 minor_hash,
2347 				struct ext4_dir_entry_2 *dirent,
2348 				struct fscrypt_str *ent_name);
2349 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2350 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2351 			     struct buffer_head *bh,
2352 			     void *buf, int buf_size,
2353 			     struct ext4_filename *fname,
2354 			     struct ext4_dir_entry_2 **dest_de);
2355 void ext4_insert_dentry(struct inode *inode,
2356 			struct ext4_dir_entry_2 *de,
2357 			int buf_size,
2358 			struct ext4_filename *fname);
2359 static inline void ext4_update_dx_flag(struct inode *inode)
2360 {
2361 	if (!ext4_has_feature_dir_index(inode->i_sb))
2362 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2363 }
2364 static const unsigned char ext4_filetype_table[] = {
2365 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2366 };
2367 
2368 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2369 {
2370 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2371 		return DT_UNKNOWN;
2372 
2373 	return ext4_filetype_table[filetype];
2374 }
2375 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2376 			     void *buf, int buf_size);
2377 
2378 /* fsync.c */
2379 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2380 
2381 /* hash.c */
2382 extern int ext4fs_dirhash(const char *name, int len, struct
2383 			  dx_hash_info *hinfo);
2384 
2385 /* ialloc.c */
2386 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2387 				      const struct qstr *qstr, __u32 goal,
2388 				      uid_t *owner, __u32 i_flags,
2389 				      int handle_type, unsigned int line_no,
2390 				      int nblocks);
2391 
2392 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2393 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2394 			 i_flags, 0, 0, 0)
2395 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2396 				    type, nblocks)		    \
2397 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2398 			 0, (type), __LINE__, (nblocks))
2399 
2400 
2401 extern void ext4_free_inode(handle_t *, struct inode *);
2402 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2403 extern unsigned long ext4_count_free_inodes(struct super_block *);
2404 extern unsigned long ext4_count_dirs(struct super_block *);
2405 extern void ext4_check_inodes_bitmap(struct super_block *);
2406 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2407 extern int ext4_init_inode_table(struct super_block *sb,
2408 				 ext4_group_t group, int barrier);
2409 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2410 
2411 /* mballoc.c */
2412 extern const struct seq_operations ext4_mb_seq_groups_ops;
2413 extern long ext4_mb_stats;
2414 extern long ext4_mb_max_to_scan;
2415 extern int ext4_mb_init(struct super_block *);
2416 extern int ext4_mb_release(struct super_block *);
2417 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2418 				struct ext4_allocation_request *, int *);
2419 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2420 extern void ext4_discard_preallocations(struct inode *);
2421 extern int __init ext4_init_mballoc(void);
2422 extern void ext4_exit_mballoc(void);
2423 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2424 			     struct buffer_head *bh, ext4_fsblk_t block,
2425 			     unsigned long count, int flags);
2426 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2427 				   ext4_group_t ngroups);
2428 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2429 		ext4_group_t i, struct ext4_group_desc *desc);
2430 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2431 				ext4_fsblk_t block, unsigned long count);
2432 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2433 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2434 
2435 /* inode.c */
2436 int ext4_inode_is_fast_symlink(struct inode *inode);
2437 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2438 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2439 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2440 		     bool wait, struct buffer_head **bhs);
2441 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2442 			     struct buffer_head *bh_result, int create);
2443 int ext4_get_block(struct inode *inode, sector_t iblock,
2444 		   struct buffer_head *bh_result, int create);
2445 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2446 		       struct buffer_head *bh_result, int create);
2447 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2448 			   struct buffer_head *bh, int create);
2449 int ext4_walk_page_buffers(handle_t *handle,
2450 			   struct buffer_head *head,
2451 			   unsigned from,
2452 			   unsigned to,
2453 			   int *partial,
2454 			   int (*fn)(handle_t *handle,
2455 				     struct buffer_head *bh));
2456 int do_journal_get_write_access(handle_t *handle,
2457 				struct buffer_head *bh);
2458 #define FALL_BACK_TO_NONDELALLOC 1
2459 #define CONVERT_INLINE_DATA	 2
2460 
2461 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2462 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2463 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2464 extern int  ext4_setattr(struct dentry *, struct iattr *);
2465 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2466 extern void ext4_evict_inode(struct inode *);
2467 extern void ext4_clear_inode(struct inode *);
2468 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2469 extern int  ext4_sync_inode(handle_t *, struct inode *);
2470 extern void ext4_dirty_inode(struct inode *, int);
2471 extern int ext4_change_inode_journal_flag(struct inode *, int);
2472 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2473 extern int ext4_inode_attach_jinode(struct inode *inode);
2474 extern int ext4_can_truncate(struct inode *inode);
2475 extern int ext4_truncate(struct inode *);
2476 extern int ext4_break_layouts(struct inode *);
2477 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2478 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2479 extern void ext4_set_inode_flags(struct inode *);
2480 extern int ext4_alloc_da_blocks(struct inode *inode);
2481 extern void ext4_set_aops(struct inode *inode);
2482 extern int ext4_writepage_trans_blocks(struct inode *);
2483 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2484 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2485 			     loff_t lstart, loff_t lend);
2486 extern int ext4_page_mkwrite(struct vm_fault *vmf);
2487 extern int ext4_filemap_fault(struct vm_fault *vmf);
2488 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2489 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2490 extern void ext4_da_update_reserve_space(struct inode *inode,
2491 					int used, int quota_claim);
2492 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2493 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2494 
2495 /* indirect.c */
2496 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2497 				struct ext4_map_blocks *map, int flags);
2498 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2499 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2500 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2501 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2502 				 ext4_lblk_t start, ext4_lblk_t end);
2503 
2504 /* ioctl.c */
2505 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2506 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2507 
2508 /* migrate.c */
2509 extern int ext4_ext_migrate(struct inode *);
2510 extern int ext4_ind_migrate(struct inode *inode);
2511 
2512 /* namei.c */
2513 extern int ext4_dirent_csum_verify(struct inode *inode,
2514 				   struct ext4_dir_entry *dirent);
2515 extern int ext4_orphan_add(handle_t *, struct inode *);
2516 extern int ext4_orphan_del(handle_t *, struct inode *);
2517 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2518 				__u32 start_minor_hash, __u32 *next_hash);
2519 extern int ext4_search_dir(struct buffer_head *bh,
2520 			   char *search_buf,
2521 			   int buf_size,
2522 			   struct inode *dir,
2523 			   struct ext4_filename *fname,
2524 			   unsigned int offset,
2525 			   struct ext4_dir_entry_2 **res_dir);
2526 extern int ext4_generic_delete_entry(handle_t *handle,
2527 				     struct inode *dir,
2528 				     struct ext4_dir_entry_2 *de_del,
2529 				     struct buffer_head *bh,
2530 				     void *entry_buf,
2531 				     int buf_size,
2532 				     int csum_size);
2533 extern bool ext4_empty_dir(struct inode *inode);
2534 
2535 /* resize.c */
2536 extern int ext4_group_add(struct super_block *sb,
2537 				struct ext4_new_group_data *input);
2538 extern int ext4_group_extend(struct super_block *sb,
2539 				struct ext4_super_block *es,
2540 				ext4_fsblk_t n_blocks_count);
2541 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2542 
2543 /* super.c */
2544 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2545 extern int ext4_calculate_overhead(struct super_block *sb);
2546 extern void ext4_superblock_csum_set(struct super_block *sb);
2547 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2548 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2549 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2550 				    ext4_group_t ngroup);
2551 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2552 				     char nbuf[16]);
2553 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2554 					     ext4_group_t block_group,
2555 					     unsigned int flags);
2556 
2557 extern __printf(4, 5)
2558 void __ext4_error(struct super_block *, const char *, unsigned int,
2559 		  const char *, ...);
2560 extern __printf(5, 6)
2561 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2562 		      const char *, ...);
2563 extern __printf(5, 6)
2564 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2565 		     const char *, ...);
2566 extern void __ext4_std_error(struct super_block *, const char *,
2567 			     unsigned int, int);
2568 extern __printf(4, 5)
2569 void __ext4_abort(struct super_block *, const char *, unsigned int,
2570 		  const char *, ...);
2571 extern __printf(4, 5)
2572 void __ext4_warning(struct super_block *, const char *, unsigned int,
2573 		    const char *, ...);
2574 extern __printf(4, 5)
2575 void __ext4_warning_inode(const struct inode *inode, const char *function,
2576 			  unsigned int line, const char *fmt, ...);
2577 extern __printf(3, 4)
2578 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2579 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2580 			   const char *, unsigned int, const char *);
2581 extern __printf(7, 8)
2582 void __ext4_grp_locked_error(const char *, unsigned int,
2583 			     struct super_block *, ext4_group_t,
2584 			     unsigned long, ext4_fsblk_t,
2585 			     const char *, ...);
2586 
2587 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2588 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2589 
2590 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2591 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2592 
2593 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2594 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2595 
2596 #ifdef CONFIG_PRINTK
2597 
2598 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2599 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2600 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2601 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2602 #define ext4_error(sb, fmt, ...)					\
2603 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2604 #define ext4_abort(sb, fmt, ...)					\
2605 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2606 #define ext4_warning(sb, fmt, ...)					\
2607 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2608 #define ext4_warning_inode(inode, fmt, ...)				\
2609 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2610 #define ext4_msg(sb, level, fmt, ...)				\
2611 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2612 #define dump_mmp_msg(sb, mmp, msg)					\
2613 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2614 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2615 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2616 				fmt, ##__VA_ARGS__)
2617 
2618 #else
2619 
2620 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2621 do {									\
2622 	no_printk(fmt, ##__VA_ARGS__);					\
2623 	__ext4_error_inode(inode, "", 0, block, " ");			\
2624 } while (0)
2625 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2626 do {									\
2627 	no_printk(fmt, ##__VA_ARGS__);					\
2628 	__ext4_error_file(file, "", 0, block, " ");			\
2629 } while (0)
2630 #define ext4_error(sb, fmt, ...)					\
2631 do {									\
2632 	no_printk(fmt, ##__VA_ARGS__);					\
2633 	__ext4_error(sb, "", 0, " ");					\
2634 } while (0)
2635 #define ext4_abort(sb, fmt, ...)					\
2636 do {									\
2637 	no_printk(fmt, ##__VA_ARGS__);					\
2638 	__ext4_abort(sb, "", 0, " ");					\
2639 } while (0)
2640 #define ext4_warning(sb, fmt, ...)					\
2641 do {									\
2642 	no_printk(fmt, ##__VA_ARGS__);					\
2643 	__ext4_warning(sb, "", 0, " ");					\
2644 } while (0)
2645 #define ext4_warning_inode(inode, fmt, ...)				\
2646 do {									\
2647 	no_printk(fmt, ##__VA_ARGS__);					\
2648 	__ext4_warning_inode(inode, "", 0, " ");			\
2649 } while (0)
2650 #define ext4_msg(sb, level, fmt, ...)					\
2651 do {									\
2652 	no_printk(fmt, ##__VA_ARGS__);					\
2653 	__ext4_msg(sb, "", " ");					\
2654 } while (0)
2655 #define dump_mmp_msg(sb, mmp, msg)					\
2656 	__dump_mmp_msg(sb, mmp, "", 0, "")
2657 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2658 do {									\
2659 	no_printk(fmt, ##__VA_ARGS__);				\
2660 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2661 } while (0)
2662 
2663 #endif
2664 
2665 extern void ext4_update_dynamic_rev(struct super_block *sb);
2666 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2667 					__u32 compat);
2668 extern int ext4_update_rocompat_feature(handle_t *handle,
2669 					struct super_block *sb,	__u32 rocompat);
2670 extern int ext4_update_incompat_feature(handle_t *handle,
2671 					struct super_block *sb,	__u32 incompat);
2672 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2673 				      struct ext4_group_desc *bg);
2674 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2675 				      struct ext4_group_desc *bg);
2676 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2677 				     struct ext4_group_desc *bg);
2678 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2679 				      struct ext4_group_desc *bg);
2680 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2681 				 struct ext4_group_desc *bg);
2682 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2683 				struct ext4_group_desc *bg);
2684 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2685 				   struct ext4_group_desc *bg);
2686 extern void ext4_block_bitmap_set(struct super_block *sb,
2687 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2688 extern void ext4_inode_bitmap_set(struct super_block *sb,
2689 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2690 extern void ext4_inode_table_set(struct super_block *sb,
2691 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2692 extern void ext4_free_group_clusters_set(struct super_block *sb,
2693 					 struct ext4_group_desc *bg,
2694 					 __u32 count);
2695 extern void ext4_free_inodes_set(struct super_block *sb,
2696 				struct ext4_group_desc *bg, __u32 count);
2697 extern void ext4_used_dirs_set(struct super_block *sb,
2698 				struct ext4_group_desc *bg, __u32 count);
2699 extern void ext4_itable_unused_set(struct super_block *sb,
2700 				   struct ext4_group_desc *bg, __u32 count);
2701 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2702 				       struct ext4_group_desc *gdp);
2703 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2704 				     struct ext4_group_desc *gdp);
2705 extern int ext4_register_li_request(struct super_block *sb,
2706 				    ext4_group_t first_not_zeroed);
2707 
2708 static inline int ext4_has_metadata_csum(struct super_block *sb)
2709 {
2710 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2711 		     !EXT4_SB(sb)->s_chksum_driver);
2712 
2713 	return ext4_has_feature_metadata_csum(sb) &&
2714 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2715 }
2716 
2717 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2718 {
2719 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2720 }
2721 
2722 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2723 {
2724 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2725 		le32_to_cpu(es->s_blocks_count_lo);
2726 }
2727 
2728 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2729 {
2730 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2731 		le32_to_cpu(es->s_r_blocks_count_lo);
2732 }
2733 
2734 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2735 {
2736 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2737 		le32_to_cpu(es->s_free_blocks_count_lo);
2738 }
2739 
2740 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2741 					 ext4_fsblk_t blk)
2742 {
2743 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2744 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2745 }
2746 
2747 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2748 					      ext4_fsblk_t blk)
2749 {
2750 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2751 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2752 }
2753 
2754 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2755 					   ext4_fsblk_t blk)
2756 {
2757 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2758 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2759 }
2760 
2761 static inline loff_t ext4_isize(struct super_block *sb,
2762 				struct ext4_inode *raw_inode)
2763 {
2764 	if (ext4_has_feature_largedir(sb) ||
2765 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2766 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2767 			le32_to_cpu(raw_inode->i_size_lo);
2768 
2769 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2770 }
2771 
2772 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2773 {
2774 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2775 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2776 }
2777 
2778 static inline
2779 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2780 					    ext4_group_t group)
2781 {
2782 	 struct ext4_group_info ***grp_info;
2783 	 long indexv, indexh;
2784 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2785 	 grp_info = EXT4_SB(sb)->s_group_info;
2786 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2787 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2788 	 return grp_info[indexv][indexh];
2789 }
2790 
2791 /*
2792  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2793  * the locking protocol documented in the comments of ext4_group_add()
2794  * in resize.c
2795  */
2796 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2797 {
2798 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2799 
2800 	smp_rmb();
2801 	return ngroups;
2802 }
2803 
2804 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2805 					     ext4_group_t block_group)
2806 {
2807 	return block_group >> sbi->s_log_groups_per_flex;
2808 }
2809 
2810 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2811 {
2812 	return 1 << sbi->s_log_groups_per_flex;
2813 }
2814 
2815 #define ext4_std_error(sb, errno)				\
2816 do {								\
2817 	if ((errno))						\
2818 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2819 } while (0)
2820 
2821 #ifdef CONFIG_SMP
2822 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2823  * counters. So we need to make sure we have free clusters more
2824  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2825  */
2826 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2827 #else
2828 #define EXT4_FREECLUSTERS_WATERMARK 0
2829 #endif
2830 
2831 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2832 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2833 {
2834 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2835 		     !inode_is_locked(inode));
2836 	down_write(&EXT4_I(inode)->i_data_sem);
2837 	if (newsize > EXT4_I(inode)->i_disksize)
2838 		EXT4_I(inode)->i_disksize = newsize;
2839 	up_write(&EXT4_I(inode)->i_data_sem);
2840 }
2841 
2842 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2843 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2844 {
2845 	int changed = 0;
2846 
2847 	if (newsize > inode->i_size) {
2848 		i_size_write(inode, newsize);
2849 		changed = 1;
2850 	}
2851 	if (newsize > EXT4_I(inode)->i_disksize) {
2852 		ext4_update_i_disksize(inode, newsize);
2853 		changed |= 2;
2854 	}
2855 	return changed;
2856 }
2857 
2858 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2859 				      loff_t len);
2860 
2861 struct ext4_group_info {
2862 	unsigned long   bb_state;
2863 	struct rb_root  bb_free_root;
2864 	ext4_grpblk_t	bb_first_free;	/* first free block */
2865 	ext4_grpblk_t	bb_free;	/* total free blocks */
2866 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2867 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2868 	struct          list_head bb_prealloc_list;
2869 #ifdef DOUBLE_CHECK
2870 	void            *bb_bitmap;
2871 #endif
2872 	struct rw_semaphore alloc_sem;
2873 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2874 					 * regions, index is order.
2875 					 * bb_counters[3] = 5 means
2876 					 * 5 free 8-block regions. */
2877 };
2878 
2879 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2880 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2881 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2882 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2883 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
2884 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
2885 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
2886 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
2887 
2888 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2889 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2890 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2891 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2892 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2893 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2894 
2895 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2896 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2897 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2898 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2899 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2900 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2901 
2902 #define EXT4_MAX_CONTENTION		8
2903 #define EXT4_CONTENTION_THRESHOLD	2
2904 
2905 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2906 					      ext4_group_t group)
2907 {
2908 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2909 }
2910 
2911 /*
2912  * Returns true if the filesystem is busy enough that attempts to
2913  * access the block group locks has run into contention.
2914  */
2915 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2916 {
2917 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2918 }
2919 
2920 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2921 {
2922 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2923 	if (spin_trylock(lock))
2924 		/*
2925 		 * We're able to grab the lock right away, so drop the
2926 		 * lock contention counter.
2927 		 */
2928 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2929 	else {
2930 		/*
2931 		 * The lock is busy, so bump the contention counter,
2932 		 * and then wait on the spin lock.
2933 		 */
2934 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2935 				  EXT4_MAX_CONTENTION);
2936 		spin_lock(lock);
2937 	}
2938 }
2939 
2940 static inline void ext4_unlock_group(struct super_block *sb,
2941 					ext4_group_t group)
2942 {
2943 	spin_unlock(ext4_group_lock_ptr(sb, group));
2944 }
2945 
2946 /*
2947  * Block validity checking
2948  */
2949 #define ext4_check_indirect_blockref(inode, bh)				\
2950 	ext4_check_blockref(__func__, __LINE__, inode,			\
2951 			    (__le32 *)(bh)->b_data,			\
2952 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2953 
2954 #define ext4_ind_check_inode(inode)					\
2955 	ext4_check_blockref(__func__, __LINE__, inode,			\
2956 			    EXT4_I(inode)->i_data,			\
2957 			    EXT4_NDIR_BLOCKS)
2958 
2959 /*
2960  * Inodes and files operations
2961  */
2962 
2963 /* dir.c */
2964 extern const struct file_operations ext4_dir_operations;
2965 
2966 /* file.c */
2967 extern const struct inode_operations ext4_file_inode_operations;
2968 extern const struct file_operations ext4_file_operations;
2969 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2970 
2971 /* inline.c */
2972 extern int ext4_get_max_inline_size(struct inode *inode);
2973 extern int ext4_find_inline_data_nolock(struct inode *inode);
2974 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2975 				 unsigned int len);
2976 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2977 
2978 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2979 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2980 					 struct inode *inode,
2981 					 loff_t pos, unsigned len,
2982 					 unsigned flags,
2983 					 struct page **pagep);
2984 extern int ext4_write_inline_data_end(struct inode *inode,
2985 				      loff_t pos, unsigned len,
2986 				      unsigned copied,
2987 				      struct page *page);
2988 extern struct buffer_head *
2989 ext4_journalled_write_inline_data(struct inode *inode,
2990 				  unsigned len,
2991 				  struct page *page);
2992 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2993 					   struct inode *inode,
2994 					   loff_t pos, unsigned len,
2995 					   unsigned flags,
2996 					   struct page **pagep,
2997 					   void **fsdata);
2998 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2999 					 unsigned len, unsigned copied,
3000 					 struct page *page);
3001 extern int ext4_try_add_inline_entry(handle_t *handle,
3002 				     struct ext4_filename *fname,
3003 				     struct inode *dir, struct inode *inode);
3004 extern int ext4_try_create_inline_dir(handle_t *handle,
3005 				      struct inode *parent,
3006 				      struct inode *inode);
3007 extern int ext4_read_inline_dir(struct file *filp,
3008 				struct dir_context *ctx,
3009 				int *has_inline_data);
3010 extern int htree_inlinedir_to_tree(struct file *dir_file,
3011 				   struct inode *dir, ext4_lblk_t block,
3012 				   struct dx_hash_info *hinfo,
3013 				   __u32 start_hash, __u32 start_minor_hash,
3014 				   int *has_inline_data);
3015 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3016 					struct ext4_filename *fname,
3017 					struct ext4_dir_entry_2 **res_dir,
3018 					int *has_inline_data);
3019 extern int ext4_delete_inline_entry(handle_t *handle,
3020 				    struct inode *dir,
3021 				    struct ext4_dir_entry_2 *de_del,
3022 				    struct buffer_head *bh,
3023 				    int *has_inline_data);
3024 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3025 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3026 					struct ext4_dir_entry_2 **parent_de,
3027 					int *retval);
3028 extern int ext4_inline_data_fiemap(struct inode *inode,
3029 				   struct fiemap_extent_info *fieinfo,
3030 				   int *has_inline, __u64 start, __u64 len);
3031 
3032 struct iomap;
3033 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3034 
3035 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3036 
3037 extern int ext4_convert_inline_data(struct inode *inode);
3038 
3039 static inline int ext4_has_inline_data(struct inode *inode)
3040 {
3041 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3042 	       EXT4_I(inode)->i_inline_off;
3043 }
3044 
3045 /* namei.c */
3046 extern const struct inode_operations ext4_dir_inode_operations;
3047 extern const struct inode_operations ext4_special_inode_operations;
3048 extern struct dentry *ext4_get_parent(struct dentry *child);
3049 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3050 				 struct ext4_dir_entry_2 *de,
3051 				 int blocksize, int csum_size,
3052 				 unsigned int parent_ino, int dotdot_real_len);
3053 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3054 				   unsigned int blocksize);
3055 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3056 					 struct inode *inode,
3057 					 struct buffer_head *bh);
3058 #define S_SHIFT 12
3059 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3060 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3061 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3062 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3063 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3064 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3065 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3066 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3067 };
3068 
3069 static inline void ext4_set_de_type(struct super_block *sb,
3070 				struct ext4_dir_entry_2 *de,
3071 				umode_t mode) {
3072 	if (ext4_has_feature_filetype(sb))
3073 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3074 }
3075 
3076 /* readpages.c */
3077 extern int ext4_mpage_readpages(struct address_space *mapping,
3078 				struct list_head *pages, struct page *page,
3079 				unsigned nr_pages, bool is_readahead);
3080 
3081 /* symlink.c */
3082 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3083 extern const struct inode_operations ext4_symlink_inode_operations;
3084 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3085 
3086 /* sysfs.c */
3087 extern int ext4_register_sysfs(struct super_block *sb);
3088 extern void ext4_unregister_sysfs(struct super_block *sb);
3089 extern int __init ext4_init_sysfs(void);
3090 extern void ext4_exit_sysfs(void);
3091 
3092 /* block_validity */
3093 extern void ext4_release_system_zone(struct super_block *sb);
3094 extern int ext4_setup_system_zone(struct super_block *sb);
3095 extern int __init ext4_init_system_zone(void);
3096 extern void ext4_exit_system_zone(void);
3097 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3098 				 ext4_fsblk_t start_blk,
3099 				 unsigned int count);
3100 extern int ext4_check_blockref(const char *, unsigned int,
3101 			       struct inode *, __le32 *, unsigned int);
3102 
3103 /* extents.c */
3104 struct ext4_ext_path;
3105 struct ext4_extent;
3106 
3107 /*
3108  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3109  * __le32.
3110  */
3111 #define EXT_MAX_BLOCKS	0xffffffff
3112 
3113 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3114 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3115 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3116 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3117 			       struct ext4_map_blocks *map, int flags);
3118 extern int ext4_ext_truncate(handle_t *, struct inode *);
3119 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3120 				 ext4_lblk_t end);
3121 extern void ext4_ext_init(struct super_block *);
3122 extern void ext4_ext_release(struct super_block *);
3123 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3124 			  loff_t len);
3125 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3126 					  loff_t offset, ssize_t len);
3127 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3128 			   struct ext4_map_blocks *map, int flags);
3129 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3130 					 ext4_lblk_t lblocks);
3131 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3132 						   int num,
3133 						   struct ext4_ext_path *path);
3134 extern int ext4_can_extents_be_merged(struct inode *inode,
3135 				      struct ext4_extent *ex1,
3136 				      struct ext4_extent *ex2);
3137 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3138 				  struct ext4_ext_path **,
3139 				  struct ext4_extent *, int);
3140 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3141 					      struct ext4_ext_path **,
3142 					      int flags);
3143 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3144 extern int ext4_ext_check_inode(struct inode *inode);
3145 extern int ext4_find_delalloc_range(struct inode *inode,
3146 				    ext4_lblk_t lblk_start,
3147 				    ext4_lblk_t lblk_end);
3148 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3149 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3150 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3151 			__u64 start, __u64 len);
3152 extern int ext4_ext_precache(struct inode *inode);
3153 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3154 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3155 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3156 				struct inode *inode2, ext4_lblk_t lblk1,
3157 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3158 			     int mark_unwritten,int *err);
3159 
3160 /* move_extent.c */
3161 extern void ext4_double_down_write_data_sem(struct inode *first,
3162 					    struct inode *second);
3163 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3164 					  struct inode *donor_inode);
3165 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3166 			     __u64 start_orig, __u64 start_donor,
3167 			     __u64 len, __u64 *moved_len);
3168 
3169 /* page-io.c */
3170 extern int __init ext4_init_pageio(void);
3171 extern void ext4_exit_pageio(void);
3172 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3173 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3174 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3175 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3176 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3177 				struct writeback_control *wbc);
3178 extern void ext4_end_io_rsv_work(struct work_struct *work);
3179 extern void ext4_io_submit(struct ext4_io_submit *io);
3180 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3181 			       struct page *page,
3182 			       int len,
3183 			       struct writeback_control *wbc,
3184 			       bool keep_towrite);
3185 
3186 /* mmp.c */
3187 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3188 
3189 /*
3190  * Add new method to test whether block and inode bitmaps are properly
3191  * initialized. With uninit_bg reading the block from disk is not enough
3192  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3193  */
3194 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3195 
3196 static inline int bitmap_uptodate(struct buffer_head *bh)
3197 {
3198 	return (buffer_uptodate(bh) &&
3199 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3200 }
3201 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3202 {
3203 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3204 }
3205 
3206 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3207 
3208 /* For ioend & aio unwritten conversion wait queues */
3209 #define EXT4_WQ_HASH_SZ		37
3210 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3211 					    EXT4_WQ_HASH_SZ])
3212 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3213 
3214 extern int ext4_resize_begin(struct super_block *sb);
3215 extern void ext4_resize_end(struct super_block *sb);
3216 
3217 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3218 					      struct ext4_io_end *io_end)
3219 {
3220 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3221 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3222 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3223 	}
3224 }
3225 
3226 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3227 {
3228 	struct inode *inode = io_end->inode;
3229 
3230 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3231 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3232 		/* Wake up anyone waiting on unwritten extent conversion */
3233 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3234 			wake_up_all(ext4_ioend_wq(inode));
3235 	}
3236 }
3237 
3238 extern const struct iomap_ops ext4_iomap_ops;
3239 
3240 #endif	/* __KERNEL__ */
3241 
3242 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3243 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3244 
3245 #endif	/* _EXT4_H */
3246