ext4.h source code [Linux/fs/ext4/ext4.h]

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/refcount.h>
21	#include <linux/types.h>
22	#include <linux/blkdev.h>
23	#include <linux/magic.h>
24	#include <linux/jbd2.h>
25	#include <linux/quota.h>
26	#include <linux/rwsem.h>
27	#include <linux/rbtree.h>
28	#include <linux/seqlock.h>
29	#include <linux/mutex.h>
30	#include <linux/timer.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 <linux/crc32c.h>
37	#include <linux/falloc.h>
38	#include <linux/percpu-rwsem.h>
39	#include <linux/fiemap.h>
40	#ifdef __KERNEL__
41	#include <linux/compat.h>
42	#endif
43	#include <uapi/linux/ext4.h>
44
45	#include <linux/fscrypt.h>
46	#include <linux/fsverity.h>
47
48	#include <linux/compiler.h>
49
50	/*
51	* The fourth extended filesystem constants/structures
52	*/
53
54	/*
55	* with AGGRESSIVE_CHECK allocator runs consistency checks over
56	* structures. these checks slow things down a lot
57	*/
58	#define AGGRESSIVE_CHECK__
59
60	/*
61	* with DOUBLE_CHECK defined mballoc creates persistent in-core
62	* bitmaps, maintains and uses them to check for double allocations
63	*/
64	#define DOUBLE_CHECK__
65
66	/*
67	* Define EXT4FS_DEBUG to produce debug messages
68	*/
69	#undef EXT4FS_DEBUG
70
71	/*
72	* Debug code
73	*/
74	#ifdef EXT4FS_DEBUG
75	#define ext4_debug(f, a...) \
76	do { \
77	printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:", \
78	__FILE__, __LINE__, __func__); \
79	printk(KERN_DEBUG f, ## a); \
80	} while (0)
81	#else
82	#define ext4_debug(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
83	#endif
84
85	/*
86	* Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
87	*/
88	#define EXT_DEBUG__
89
90	/*
91	* Dynamic printk for controlled extents debugging.
92	*/
93	#ifdef CONFIG_EXT4_DEBUG
94	#define ext_debug(ino, fmt, ...) \
95	pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt, \
96	current->comm, task_pid_nr(current), \
97	ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__, \
98	__func__, ##__VA_ARGS__)
99	#else
100	#define ext_debug(ino, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
101	#endif
102
103	#define ASSERT(assert) \
104	do { \
105	if (unlikely(!(assert))) { \
106	printk(KERN_EMERG \
107	"Assertion failure in %s() at %s:%d: '%s'\n", \
108	__func__, __FILE__, __LINE__, #assert); \
109	BUG(); \
110	} \
111	} while (0)
112
113	/ data type for block offset of block group /
114	typedef int ext4_grpblk_t;
115
116	/ data type for filesystem-wide blocks number /
117	typedef unsigned long long ext4_fsblk_t;
118
119	/ data type for file logical block number /
120	typedef __u32 ext4_lblk_t;
121
122	/ data type for block group number /
123	typedef unsigned int ext4_group_t;
124
125	enum SHIFT_DIRECTION {
126	SHIFT_LEFT = `0`,
127	SHIFT_RIGHT,
128	};
129
130	/*
131	* For each criteria, mballoc has slightly different way of finding
132	* the required blocks nad usually, higher the criteria the slower the
133	* allocation. We start at lower criterias and keep falling back to
134	* higher ones if we are not able to find any blocks. Lower (earlier)
135	* criteria are faster.
136	*/
137	enum criteria {
138	/*
139	* Used when number of blocks needed is a power of 2. This
140	* doesn't trigger any disk IO except prefetch and is the
141	* fastest criteria.
142	*/
143	CR_POWER2_ALIGNED,
144
145	/*
146	* Tries to lookup in-memory data structures to find the most
147	* suitable group that satisfies goal request. No disk IO
148	* except block prefetch.
149	*/
150	CR_GOAL_LEN_FAST,
151
152	/*
153	* Same as CR_GOAL_LEN_FAST but is allowed to reduce the goal
154	* length to the best available length for faster allocation.
155	*/
156	CR_BEST_AVAIL_LEN,
157
158	/*
159	* Reads each block group sequentially, performing disk IO if
160	* necessary, to find suitable block group. Tries to
161	* allocate goal length but might trim the request if nothing
162	* is found after enough tries.
163	*/
164	CR_GOAL_LEN_SLOW,
165
166	/*
167	* Finds the first free set of blocks and allocates
168	* those. This is only used in rare cases when
169	* CR_GOAL_LEN_SLOW also fails to allocate anything.
170	*/
171	CR_ANY_FREE,
172
173	/*
174	* Number of criterias defined.
175	*/
176	EXT4_MB_NUM_CRS
177	};
178
179	/*
180	* Flags used in mballoc's allocation_context flags field.
181	*
182	* Also used to show what's going on for debugging purposes when the
183	* flag field is exported via the traceport interface
184	*/
185
186	/ prefer goal again. length /
187	#define EXT4_MB_HINT_MERGE 0x0001
188	/ first blocks in the file /
189	#define EXT4_MB_HINT_FIRST 0x0008
190	/ data is being allocated /
191	#define EXT4_MB_HINT_DATA 0x0020
192	/ don't preallocate (for tails) /
193	#define EXT4_MB_HINT_NOPREALLOC 0x0040
194	/ allocate for locality group /
195	#define EXT4_MB_HINT_GROUP_ALLOC 0x0080
196	/ allocate goal blocks or none /
197	#define EXT4_MB_HINT_GOAL_ONLY 0x0100
198	/ goal is meaningful /
199	#define EXT4_MB_HINT_TRY_GOAL 0x0200
200	/ blocks already pre-reserved by delayed allocation /
201	#define EXT4_MB_DELALLOC_RESERVED 0x0400
202	/ We are doing stream allocation /
203	#define EXT4_MB_STREAM_ALLOC 0x0800
204	/ Use reserved root blocks if needed /
205	#define EXT4_MB_USE_ROOT_BLOCKS 0x1000
206	/ Use blocks from reserved pool /
207	#define EXT4_MB_USE_RESERVED 0x2000
208	/ Do strict check for free blocks while retrying block allocation /
209	#define EXT4_MB_STRICT_CHECK 0x4000
210
211	struct ext4_allocation_request {
212	/ target inode for block we're allocating /
213	struct inode *inode;
214	/ how many blocks we want to allocate /
215	unsigned int len;
216	/ logical block in target inode /
217	ext4_lblk_t logical;
218	/ the closest logical allocated block to the left /
219	ext4_lblk_t lleft;
220	/ the closest logical allocated block to the right /
221	ext4_lblk_t lright;
222	/ phys. target (a hint) /
223	ext4_fsblk_t goal;
224	/ phys. block for the closest logical allocated block to the left /
225	ext4_fsblk_t pleft;
226	/ phys. block for the closest logical allocated block to the right /
227	ext4_fsblk_t pright;
228	/ flags. see above EXT4_MB_HINT_* /
229	unsigned int flags;
230	};
231
232	/*
233	* Logical to physical block mapping, used by ext4_map_blocks()
234	*
235	* This structure is used to pass requests into ext4_map_blocks() as
236	* well as to store the information returned by ext4_map_blocks(). It
237	* takes less room on the stack than a struct buffer_head.
238	*/
239	#define EXT4_MAP_NEW BIT(BH_New)
240	#define EXT4_MAP_MAPPED BIT(BH_Mapped)
241	#define EXT4_MAP_UNWRITTEN BIT(BH_Unwritten)
242	#define EXT4_MAP_BOUNDARY BIT(BH_Boundary)
243	#define EXT4_MAP_DELAYED BIT(BH_Delay)
244	/*
245	* This is for use in ext4_map_query_blocks() for a special case where we can
246	* have a physically and logically contiguous blocks split across two leaf
247	* nodes instead of a single extent. This is required in case of atomic writes
248	* to know whether the returned extent is last in leaf. If yes, then lookup for
249	* next in leaf block in ext4_map_query_blocks_next_in_leaf().
250	* - This is never going to be added to any buffer head state.
251	* - We use the next available bit after BH_BITMAP_UPTODATE.
252	*/
253	#define EXT4_MAP_QUERY_LAST_IN_LEAF BIT(BH_BITMAP_UPTODATE + 1)
254	#define EXT4_MAP_FLAGS (EXT4_MAP_NEW \| EXT4_MAP_MAPPED \|\
255	EXT4_MAP_UNWRITTEN \| EXT4_MAP_BOUNDARY \|\
256	EXT4_MAP_DELAYED \| EXT4_MAP_QUERY_LAST_IN_LEAF)
257
258	struct ext4_map_blocks {
259	ext4_fsblk_t m_pblk;
260	ext4_lblk_t m_lblk;
261	unsigned int m_len;
262	unsigned int m_flags;
263	};
264
265	/*
266	* Block validity checking, system zone rbtree.
267	*/
268	struct ext4_system_blocks {
269	struct rb_root root;
270	struct rcu_head rcu;
271	};
272
273	/*
274	* Flags for ext4_io_end->flags
275	*/
276	#define EXT4_IO_END_UNWRITTEN 0x0001
277	#define EXT4_IO_END_FAILED 0x0002
278
279	#define EXT4_IO_END_DEFER_COMPLETION (EXT4_IO_END_UNWRITTEN \| EXT4_IO_END_FAILED)
280
281	struct ext4_io_end_vec {
282	struct list_head list; / list of io_end_vec /
283	loff_t offset; / offset in the file /
284	ssize_t size; / size of the extent /
285	};
286
287	/*
288	* For converting unwritten extents on a work queue. 'handle' is used for
289	* buffered writeback.
290	*/
291	typedef struct ext4_io_end {
292	struct list_head list; / per-file finished IO list /
293	handle_t handle; /* handle reserved for extent*
294	* conversion */
295	struct inode inode; /* file being written to /
296	struct bio bio; /* Linked list of completed*
297	* bios covering the extent */
298	unsigned int flag; / unwritten or not /
299	refcount_t count; / reference counter /
300	struct list_head list_vec; / list of ext4_io_end_vec /
301	} ext4_io_end_t;
302
303	struct ext4_io_submit {
304	struct writeback_control *io_wbc;
305	struct bio *io_bio;
306	ext4_io_end_t *io_end;
307	sector_t io_next_block;
308	};
309
310	/*
311	* Special inodes numbers
312	*/
313	#define EXT4_BAD_INO 1 /* Bad blocks inode */
314	#define EXT4_ROOT_INO 2 /* Root inode */
315	#define EXT4_USR_QUOTA_INO 3 /* User quota inode */
316	#define EXT4_GRP_QUOTA_INO 4 /* Group quota inode */
317	#define EXT4_BOOT_LOADER_INO 5 /* Boot loader inode */
318	#define EXT4_UNDEL_DIR_INO 6 /* Undelete directory inode */
319	#define EXT4_RESIZE_INO 7 /* Reserved group descriptors inode */
320	#define EXT4_JOURNAL_INO 8 /* Journal inode */
321
322	/ First non-reserved inode for old ext4 filesystems /
323	#define EXT4_GOOD_OLD_FIRST_INO 11
324
325	/*
326	* Maximal count of links to a file
327	*/
328	#define EXT4_LINK_MAX 65000
329
330	/*
331	* Macro-instructions used to manage several block sizes
332	*/
333	#define EXT4_MIN_BLOCK_SIZE 1024
334	#define EXT4_MAX_BLOCK_SIZE 65536
335	#define EXT4_MIN_BLOCK_LOG_SIZE 10
336	#define EXT4_MAX_BLOCK_LOG_SIZE 16
337	#define EXT4_MAX_CLUSTER_LOG_SIZE 30
338	#ifdef __KERNEL__
339	# define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize)
340	#else
341	# define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
342	#endif
343	#define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
344	#define EXT4_CLUSTER_SIZE(s) (EXT4_BLOCK_SIZE(s) << \
345	EXT4_SB(s)->s_cluster_bits)
346	#ifdef __KERNEL__
347	# define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
348	# define EXT4_CLUSTER_BITS(s) (EXT4_SB(s)->s_cluster_bits)
349	#else
350	# define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
351	#endif
352	#ifdef __KERNEL__
353	#define EXT4_ADDR_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_addr_per_block_bits)
354	#define EXT4_INODE_SIZE(s) (EXT4_SB(s)->s_inode_size)
355	#define EXT4_FIRST_INO(s) (EXT4_SB(s)->s_first_ino)
356	#else
357	#define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
358	EXT4_GOOD_OLD_INODE_SIZE : \
359	(s)->s_inode_size)
360	#define EXT4_FIRST_INO(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
361	EXT4_GOOD_OLD_FIRST_INO : \
362	(s)->s_first_ino)
363	#endif
364	#define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
365	#define EXT4_MAX_BLOCKS(size, offset, blkbits) \
366	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
367	blkbits))
368	#define EXT4_B_TO_LBLK(inode, offset) \
369	(round_up((offset), i_blocksize(inode)) >> (inode)->i_blkbits)
370
371	/ Translate a block number to a cluster number /
372	#define EXT4_B2C(sbi, blk) ((blk) >> (sbi)->s_cluster_bits)
373	/ Translate a cluster number to a block number /
374	#define EXT4_C2B(sbi, cluster) ((cluster) << (sbi)->s_cluster_bits)
375	/ Translate # of blks to # of clusters /
376	#define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
377	(sbi)->s_cluster_bits)
378	/ Mask out the low bits to get the starting block of the cluster /
379	#define EXT4_PBLK_CMASK(s, pblk) ((pblk) & \
380	~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
381	#define EXT4_LBLK_CMASK(s, lblk) ((lblk) & \
382	~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
383	/ Fill in the low bits to get the last block of the cluster /
384	#define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) \| \
385	((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
386	/ Get the cluster offset /
387	#define EXT4_PBLK_COFF(s, pblk) ((pblk) & \
388	((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
389	#define EXT4_LBLK_COFF(s, lblk) ((lblk) & \
390	((ext4_lblk_t) (s)->s_cluster_ratio - 1))
391
392	/*
393	* Structure of a blocks group descriptor
394	*/
395	struct ext4_group_desc
396	{
397	__le32 bg_block_bitmap_lo; / Blocks bitmap block /
398	__le32 bg_inode_bitmap_lo; / Inodes bitmap block /
399	__le32 bg_inode_table_lo; / Inodes table block /
400	__le16 bg_free_blocks_count_lo;/ Free blocks count /
401	__le16 bg_free_inodes_count_lo;/ Free inodes count /
402	__le16 bg_used_dirs_count_lo; / Directories count /
403	__le16 bg_flags; / EXT4_BG_flags (INODE_UNINIT, etc) /
404	__le32 bg_exclude_bitmap_lo; / Exclude bitmap for snapshots /
405	__le16 bg_block_bitmap_csum_lo;/ crc32c(s_uuid+grp_num+bbitmap) LE /
406	__le16 bg_inode_bitmap_csum_lo;/ crc32c(s_uuid+grp_num+ibitmap) LE /
407	__le16 bg_itable_unused_lo; / Unused inodes count /
408	__le16 bg_checksum; / crc16(sb_uuid+group+desc) /
409	__le32 bg_block_bitmap_hi; / Blocks bitmap block MSB /
410	__le32 bg_inode_bitmap_hi; / Inodes bitmap block MSB /
411	__le32 bg_inode_table_hi; / Inodes table block MSB /
412	__le16 bg_free_blocks_count_hi;/ Free blocks count MSB /
413	__le16 bg_free_inodes_count_hi;/ Free inodes count MSB /
414	__le16 bg_used_dirs_count_hi; / Directories count MSB /
415	__le16 bg_itable_unused_hi; / Unused inodes count MSB /
416	__le32 bg_exclude_bitmap_hi; / Exclude bitmap block MSB /
417	__le16 bg_block_bitmap_csum_hi;/ crc32c(s_uuid+grp_num+bbitmap) BE /
418	__le16 bg_inode_bitmap_csum_hi;/ crc32c(s_uuid+grp_num+ibitmap) BE /
419	__u32 bg_reserved;
420	};
421
422	#define EXT4_BG_INODE_BITMAP_CSUM_HI_END \
423	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
424	sizeof(__le16))
425	#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END \
426	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
427	sizeof(__le16))
428
429	/*
430	* Structure of a flex block group info
431	*/
432
433	struct flex_groups {
434	atomic64_t free_clusters;
435	atomic_t free_inodes;
436	atomic_t used_dirs;
437	};
438
439	#define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */
440	#define EXT4_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */
441	#define EXT4_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
442
443	/*
444	* Macro-instructions used to manage group descriptors
445	*/
446	#define EXT4_MIN_DESC_SIZE 32
447	#define EXT4_MIN_DESC_SIZE_64BIT 64
448	#define EXT4_MAX_DESC_SIZE EXT4_MIN_BLOCK_SIZE
449	#define EXT4_DESC_SIZE(s) (EXT4_SB(s)->s_desc_size)
450	#ifdef __KERNEL__
451	# define EXT4_BLOCKS_PER_GROUP(s) (EXT4_SB(s)->s_blocks_per_group)
452	# define EXT4_CLUSTERS_PER_GROUP(s) (EXT4_SB(s)->s_clusters_per_group)
453	# define EXT4_DESC_PER_BLOCK(s) (EXT4_SB(s)->s_desc_per_block)
454	# define EXT4_INODES_PER_GROUP(s) (EXT4_SB(s)->s_inodes_per_group)
455	# define EXT4_DESC_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_desc_per_block_bits)
456	#else
457	# define EXT4_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
458	# define EXT4_DESC_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
459	# define EXT4_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
460	#endif
461
462	/*
463	* Constants relative to the data blocks
464	*/
465	#define EXT4_NDIR_BLOCKS 12
466	#define EXT4_IND_BLOCK EXT4_NDIR_BLOCKS
467	#define EXT4_DIND_BLOCK (EXT4_IND_BLOCK + 1)
468	#define EXT4_TIND_BLOCK (EXT4_DIND_BLOCK + 1)
469	#define EXT4_N_BLOCKS (EXT4_TIND_BLOCK + 1)
470
471	/*
472	* Inode flags
473	*/
474	#define EXT4_SECRM_FL 0x00000001 /* Secure deletion */
475	#define EXT4_UNRM_FL 0x00000002 /* Undelete */
476	#define EXT4_COMPR_FL 0x00000004 /* Compress file */
477	#define EXT4_SYNC_FL 0x00000008 /* Synchronous updates */
478	#define EXT4_IMMUTABLE_FL 0x00000010 /* Immutable file */
479	#define EXT4_APPEND_FL 0x00000020 /* writes to file may only append */
480	#define EXT4_NODUMP_FL 0x00000040 /* do not dump file */
481	#define EXT4_NOATIME_FL 0x00000080 /* do not update atime */
482	/ Reserved for compression usage... /
483	#define EXT4_DIRTY_FL 0x00000100
484	#define EXT4_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
485	#define EXT4_NOCOMPR_FL 0x00000400 /* Don't compress */
486	/ nb: was previously EXT2_ECOMPR_FL /
487	#define EXT4_ENCRYPT_FL 0x00000800 /* encrypted file */
488	/ End compression flags --- maybe not all used /
489	#define EXT4_INDEX_FL 0x00001000 /* hash-indexed directory */
490	#define EXT4_IMAGIC_FL 0x00002000 /* AFS directory */
491	#define EXT4_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
492	#define EXT4_NOTAIL_FL 0x00008000 /* file tail should not be merged */
493	#define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
494	#define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
495	#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
496	#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
497	#define EXT4_VERITY_FL 0x00100000 /* Verity protected inode */
498	#define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */
499	/ 0x00400000 was formerly EXT4_EOFBLOCKS_FL /
500
501	#define EXT4_DAX_FL 0x02000000 /* Inode is DAX */
502
503	#define EXT4_INLINE_DATA_FL 0x10000000 /* Inode has inline data. */
504	#define EXT4_PROJINHERIT_FL 0x20000000 /* Create with parents projid */
505	#define EXT4_CASEFOLD_FL 0x40000000 /* Casefolded directory */
506	#define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
507
508	/ User modifiable flags /
509	#define EXT4_FL_USER_MODIFIABLE (EXT4_SECRM_FL \| \
510	EXT4_UNRM_FL \| \
511	EXT4_COMPR_FL \| \
512	EXT4_SYNC_FL \| \
513	EXT4_IMMUTABLE_FL \| \
514	EXT4_APPEND_FL \| \
515	EXT4_NODUMP_FL \| \
516	EXT4_NOATIME_FL \| \
517	EXT4_JOURNAL_DATA_FL \| \
518	EXT4_NOTAIL_FL \| \
519	EXT4_DIRSYNC_FL \| \
520	EXT4_TOPDIR_FL \| \
521	EXT4_EXTENTS_FL \| \
522	0x00400000 /* EXT4_EOFBLOCKS_FL */ \| \
523	EXT4_DAX_FL \| \
524	EXT4_PROJINHERIT_FL \| \
525	EXT4_CASEFOLD_FL)
526
527	/ User visible flags /
528	#define EXT4_FL_USER_VISIBLE (EXT4_FL_USER_MODIFIABLE \| \
529	EXT4_DIRTY_FL \| \
530	EXT4_COMPRBLK_FL \| \
531	EXT4_NOCOMPR_FL \| \
532	EXT4_ENCRYPT_FL \| \
533	EXT4_INDEX_FL \| \
534	EXT4_VERITY_FL \| \
535	EXT4_INLINE_DATA_FL)
536
537	/ Flags that should be inherited by new inodes from their parent. /
538	#define EXT4_FL_INHERITED (EXT4_SECRM_FL \| EXT4_UNRM_FL \| EXT4_COMPR_FL \|\
539	EXT4_SYNC_FL \| EXT4_NODUMP_FL \| EXT4_NOATIME_FL \|\
540	EXT4_NOCOMPR_FL \| EXT4_JOURNAL_DATA_FL \|\
541	EXT4_NOTAIL_FL \| EXT4_DIRSYNC_FL \|\
542	EXT4_PROJINHERIT_FL \| EXT4_CASEFOLD_FL \|\
543	EXT4_DAX_FL)
544
545	/ Flags that are appropriate for regular files (all but dir-specific ones). /
546	#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL \| EXT4_TOPDIR_FL \| EXT4_CASEFOLD_FL \|\
547	EXT4_PROJINHERIT_FL))
548
549	/ Flags that are appropriate for non-directories/regular files. /
550	#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL \| EXT4_NOATIME_FL)
551
552	/ The only flags that should be swapped /
553	#define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL \| EXT4_EXTENTS_FL)
554
555	/ Flags which are mutually exclusive to DAX /
556	#define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL \| EXT4_ENCRYPT_FL \|\
557	EXT4_JOURNAL_DATA_FL \| EXT4_INLINE_DATA_FL)
558
559	/ Mask out flags that are inappropriate for the given type of inode. /
560	static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
561	{
562	if (S_ISDIR(mode))
563	return flags;
564	else if (S_ISREG(mode))
565	return flags & EXT4_REG_FLMASK;
566	else
567	return flags & EXT4_OTHER_FLMASK;
568	}
569
570	/*
571	* Inode flags used for atomic set/get
572	*/
573	enum {
574	EXT4_INODE_SECRM = `0`, / Secure deletion /
575	EXT4_INODE_UNRM = `1`, / Undelete /
576	EXT4_INODE_COMPR = `2`, / Compress file /
577	EXT4_INODE_SYNC = `3`, / Synchronous updates /
578	EXT4_INODE_IMMUTABLE = `4`, / Immutable file /
579	EXT4_INODE_APPEND = `5`, / writes to file may only append /
580	EXT4_INODE_NODUMP = `6`, / do not dump file /
581	EXT4_INODE_NOATIME = `7`, / do not update atime /
582	/ Reserved for compression usage... /
583	EXT4_INODE_DIRTY = `8`,
584	EXT4_INODE_COMPRBLK = `9`, / One or more compressed clusters /
585	EXT4_INODE_NOCOMPR = `10`, / Don't compress /
586	EXT4_INODE_ENCRYPT = `11`, / Encrypted file /
587	/ End compression flags --- maybe not all used /
588	EXT4_INODE_INDEX = `12`, / hash-indexed directory /
589	EXT4_INODE_IMAGIC = `13`, / AFS directory /
590	EXT4_INODE_JOURNAL_DATA = `14`, / file data should be journaled /
591	EXT4_INODE_NOTAIL = `15`, / file tail should not be merged /
592	EXT4_INODE_DIRSYNC = `16`, / dirsync behaviour (directories only) /
593	EXT4_INODE_TOPDIR = `17`, / Top of directory hierarchies/
594	EXT4_INODE_HUGE_FILE = `18`, / Set to each huge file /
595	EXT4_INODE_EXTENTS = `19`, / Inode uses extents /
596	EXT4_INODE_VERITY = `20`, / Verity protected inode /
597	EXT4_INODE_EA_INODE = `21`, / Inode used for large EA /
598	/ 22 was formerly EXT4_INODE_EOFBLOCKS /
599	EXT4_INODE_DAX = `25`, / Inode is DAX /
600	EXT4_INODE_INLINE_DATA = `28`, / Data in inode. /
601	EXT4_INODE_PROJINHERIT = `29`, / Create with parents projid /
602	EXT4_INODE_CASEFOLD = `30`, / Casefolded directory /
603	EXT4_INODE_RESERVED = `31`, / reserved for ext4 lib /
604	};
605
606	/*
607	* Since it's pretty easy to mix up bit numbers and hex values, we use a
608	* build-time check to make sure that EXT4_XXX_FL is consistent with respect to
609	* EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
610	* any extra space in the compiled kernel image, otherwise, the build will fail.
611	* It's important that these values are the same, since we are using
612	* EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
613	* with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
614	* values found in ext2, ext3 and ext4 filesystems, and of course the values
615	* defined in e2fsprogs.
616	*
617	* It's not paranoia if the Murphy's Law really is out to get you. :-)
618	*/
619	#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1U << EXT4_INODE_##FLAG))
620	#define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
621
622	static inline void ext4_check_flag_values(void)
623	{
624	CHECK_FLAG_VALUE(SECRM);
625	CHECK_FLAG_VALUE(UNRM);
626	CHECK_FLAG_VALUE(COMPR);
627	CHECK_FLAG_VALUE(SYNC);
628	CHECK_FLAG_VALUE(IMMUTABLE);
629	CHECK_FLAG_VALUE(APPEND);
630	CHECK_FLAG_VALUE(NODUMP);
631	CHECK_FLAG_VALUE(NOATIME);
632	CHECK_FLAG_VALUE(DIRTY);
633	CHECK_FLAG_VALUE(COMPRBLK);
634	CHECK_FLAG_VALUE(NOCOMPR);
635	CHECK_FLAG_VALUE(ENCRYPT);
636	CHECK_FLAG_VALUE(INDEX);
637	CHECK_FLAG_VALUE(IMAGIC);
638	CHECK_FLAG_VALUE(JOURNAL_DATA);
639	CHECK_FLAG_VALUE(NOTAIL);
640	CHECK_FLAG_VALUE(DIRSYNC);
641	CHECK_FLAG_VALUE(TOPDIR);
642	CHECK_FLAG_VALUE(HUGE_FILE);
643	CHECK_FLAG_VALUE(EXTENTS);
644	CHECK_FLAG_VALUE(VERITY);
645	CHECK_FLAG_VALUE(EA_INODE);
646	CHECK_FLAG_VALUE(INLINE_DATA);
647	CHECK_FLAG_VALUE(PROJINHERIT);
648	CHECK_FLAG_VALUE(CASEFOLD);
649	CHECK_FLAG_VALUE(RESERVED);
650	}
651
652	#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
653	struct compat_ext4_new_group_input {
654	u32 group;
655	compat_u64 block_bitmap;
656	compat_u64 inode_bitmap;
657	compat_u64 inode_table;
658	u32 blocks_count;
659	u16 reserved_blocks;
660	u16 unused;
661	};
662	#endif
663
664	/ The struct ext4_new_group_input in kernel space, with free_blocks_count /
665	struct ext4_new_group_data {
666	__u32 group;
667	__u64 block_bitmap;
668	__u64 inode_bitmap;
669	__u64 inode_table;
670	__u32 blocks_count;
671	__u16 reserved_blocks;
672	__u16 mdata_blocks;
673	__u32 free_clusters_count;
674	};
675
676	/ Indexes used to index group tables in ext4_new_group_data /
677	enum {
678	BLOCK_BITMAP = `0`, / block bitmap /
679	INODE_BITMAP, / inode bitmap /
680	INODE_TABLE, / inode tables /
681	GROUP_TABLE_COUNT,
682	};
683
684	/*
685	* Flags used by ext4_map_blocks()
686	*/
687	/ Allocate any needed blocks and/or convert an unwritten*
688	extent to be an initialized ext4 /*
689	#define EXT4_GET_BLOCKS_CREATE 0x0001
690	/ Request the creation of an unwritten extent /
691	#define EXT4_GET_BLOCKS_UNWRIT_EXT 0x0002
692	#define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT (EXT4_GET_BLOCKS_UNWRIT_EXT\|\
693	EXT4_GET_BLOCKS_CREATE)
694	/ Caller is from the delayed allocation writeout path*
695	* finally doing the actual allocation of delayed blocks */
696	#define EXT4_GET_BLOCKS_DELALLOC_RESERVE 0x0004
697	/ caller is from the direct IO path, request to creation of an*
698	unwritten extents if not allocated, split the unwritten
699	extent if blocks has been preallocated already/*
700	#define EXT4_GET_BLOCKS_PRE_IO 0x0008
701	#define EXT4_GET_BLOCKS_CONVERT 0x0010
702	#define EXT4_GET_BLOCKS_IO_CREATE_EXT (EXT4_GET_BLOCKS_PRE_IO\|\
703	EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
704	/ Eventual metadata allocation (due to growing extent tree)*
705	* should not fail, so try to use reserved blocks for that.*/
706	#define EXT4_GET_BLOCKS_METADATA_NOFAIL 0x0020
707	/ Don't normalize allocation size (used for fallocate) /
708	#define EXT4_GET_BLOCKS_NO_NORMALIZE 0x0040
709	/ Convert written extents to unwritten /
710	#define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN 0x0100
711	/ Write zeros to newly created written extents /
712	#define EXT4_GET_BLOCKS_ZERO 0x0200
713	#define EXT4_GET_BLOCKS_CREATE_ZERO (EXT4_GET_BLOCKS_CREATE \|\
714	EXT4_GET_BLOCKS_ZERO)
715	/ Caller is in the context of data submission, such as writeback,*
716	* fsync, etc. Especially, in the generic writeback path, caller will
717	* submit data before dropping transaction handle. This allows jbd2
718	* to avoid submitting data before commit. */
719	#define EXT4_GET_BLOCKS_IO_SUBMIT 0x0400
720	/ Convert extent to initialized after IO complete /
721	#define EXT4_GET_BLOCKS_IO_CONVERT_EXT (EXT4_GET_BLOCKS_CONVERT \|\
722	EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT \|\
723	EXT4_GET_BLOCKS_IO_SUBMIT)
724	/ Caller is in the atomic contex, find extent if it has been cached /
725	#define EXT4_GET_BLOCKS_CACHED_NOWAIT 0x0800
726	/*
727	* Atomic write caller needs this to query in the slow path of mixed mapping
728	* case, when a contiguous extent can be split across two adjacent leaf nodes.
729	* Look EXT4_MAP_QUERY_LAST_IN_LEAF.
730	*/
731	#define EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF 0x1000
732
733	/*
734	* The bit position of these flags must not overlap with any of the
735	* EXT4_GET_BLOCKS_*. They are used by ext4_find_extent(),
736	* read_extent_tree_block(), ext4_split_extent_at(),
737	* ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
738	* EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
739	* caching the extents when reading from the extent tree while a
740	* truncate or punch hole operation is in progress.
741	*/
742	#define EXT4_EX_NOCACHE 0x40000000
743	#define EXT4_EX_FORCE_CACHE 0x20000000
744	#define EXT4_EX_NOFAIL 0x10000000
745	/*
746	* ext4_map_query_blocks() uses this filter mask to filter the flags needed to
747	* pass while lookup/querying of on disk extent tree.
748	*/
749	#define EXT4_EX_QUERY_FILTER (EXT4_EX_NOCACHE \| EXT4_EX_FORCE_CACHE \|\
750	EXT4_EX_NOFAIL \|\
751	EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF)
752
753	/*
754	* Flags used by ext4_free_blocks
755	*/
756	#define EXT4_FREE_BLOCKS_METADATA 0x0001
757	#define EXT4_FREE_BLOCKS_FORGET 0x0002
758	#define EXT4_FREE_BLOCKS_VALIDATED 0x0004
759	#define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
760	#define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER 0x0010
761	#define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER 0x0020
762	#define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER 0x0040
763
764	#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
765	/*
766	* ioctl commands in 32 bit emulation
767	*/
768	#define EXT4_IOC32_GETVERSION _IOR('f', 3, int)
769	#define EXT4_IOC32_SETVERSION _IOW('f', 4, int)
770	#define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int)
771	#define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int)
772	#define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int)
773	#define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input)
774	#define EXT4_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION
775	#define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
776	#endif
777
778	/ Max physical block we can address w/o extents /
779	#define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF
780
781	/ Max logical block we can support /
782	#define EXT4_MAX_LOGICAL_BLOCK 0xFFFFFFFE
783
784	/*
785	* Structure of an inode on the disk
786	*/
787	struct ext4_inode {
788	__le16 i_mode; / File mode /
789	__le16 i_uid; / Low 16 bits of Owner Uid /
790	__le32 i_size_lo; / Size in bytes /
791	__le32 i_atime; / Access time /
792	__le32 i_ctime; / Inode Change time /
793	__le32 i_mtime; / Modification time /
794	__le32 i_dtime; / Deletion Time /
795	__le16 i_gid; / Low 16 bits of Group Id /
796	__le16 i_links_count; / Links count /
797	__le32 i_blocks_lo; / Blocks count /
798	__le32 i_flags; / File flags /
799	union {
800	struct {
801	__le32 l_i_version;
802	} linux1;
803	struct {
804	__u32 h_i_translator;
805	} hurd1;
806	struct {
807	__u32 m_i_reserved1;
808	} masix1;
809	} osd1; / OS dependent 1 /
810	__le32 i_block[EXT4_N_BLOCKS];/ Pointers to blocks /
811	__le32 i_generation; / File version (for NFS) /
812	__le32 i_file_acl_lo; / File ACL /
813	__le32 i_size_high;
814	__le32 i_obso_faddr; / Obsoleted fragment address /
815	union {
816	struct {
817	__le16 l_i_blocks_high; / were l_i_reserved1 /
818	__le16 l_i_file_acl_high;
819	__le16 l_i_uid_high; / these 2 fields /
820	__le16 l_i_gid_high; / were reserved2[0] /
821	__le16 l_i_checksum_lo;/ crc32c(uuid+inum+inode) LE /
822	__le16 l_i_reserved;
823	} linux2;
824	struct {
825	__le16 h_i_reserved1; / Obsoleted fragment number/size which are removed in ext4 /
826	__u16 h_i_mode_high;
827	__u16 h_i_uid_high;
828	__u16 h_i_gid_high;
829	__u32 h_i_author;
830	} hurd2;
831	struct {
832	__le16 h_i_reserved1; / Obsoleted fragment number/size which are removed in ext4 /
833	__le16 m_i_file_acl_high;
834	__u32 m_i_reserved2[`2`];
835	} masix2;
836	} osd2; / OS dependent 2 /
837	__le16 i_extra_isize;
838	__le16 i_checksum_hi; / crc32c(uuid+inum+inode) BE /
839	__le32 i_ctime_extra; / extra Change time (nsec << 2 \| epoch) /
840	__le32 i_mtime_extra; / extra Modification time(nsec << 2 \| epoch) /
841	__le32 i_atime_extra; / extra Access time (nsec << 2 \| epoch) /
842	__le32 i_crtime; / File Creation time /
843	__le32 i_crtime_extra; / extra FileCreationtime (nsec << 2 \| epoch) /
844	__le32 i_version_hi; / high 32 bits for 64-bit version /
845	__le32 i_projid; / Project ID /
846	};
847
848	#define EXT4_EPOCH_BITS 2
849	#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
850	#define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS)
851
852	/*
853	* Extended fields will fit into an inode if the filesystem was formatted
854	* with large inodes (-I 256 or larger) and there are not currently any EAs
855	* consuming all of the available space. For new inodes we always reserve
856	* enough space for the kernel's known extended fields, but for inodes
857	* created with an old kernel this might not have been the case. None of
858	* the extended inode fields is critical for correct filesystem operation.
859	* This macro checks if a certain field fits in the inode. Note that
860	* inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
861	*/
862	#define EXT4_FITS_IN_INODE(ext4_inode, einode, field) \
863	((offsetof(typeof(*ext4_inode), field) + \
864	sizeof((ext4_inode)->field)) \
865	<= (EXT4_GOOD_OLD_INODE_SIZE + \
866	(einode)->i_extra_isize)) \
867
868	/*
869	* We use an encoding that preserves the times for extra epoch "00":
870	*
871	* extra msb of adjust for signed
872	* epoch 32-bit 32-bit tv_sec to
873	* bits time decoded 64-bit tv_sec 64-bit tv_sec valid time range
874	* 0 0 1 -0x80000000..-0x00000001 0x000000000 1901-12-13..1969-12-31
875	* 0 0 0 0x000000000..0x07fffffff 0x000000000 1970-01-01..2038-01-19
876	* 0 1 1 0x080000000..0x0ffffffff 0x100000000 2038-01-19..2106-02-07
877	* 0 1 0 0x100000000..0x17fffffff 0x100000000 2106-02-07..2174-02-25
878	* 1 0 1 0x180000000..0x1ffffffff 0x200000000 2174-02-25..2242-03-16
879	* 1 0 0 0x200000000..0x27fffffff 0x200000000 2242-03-16..2310-04-04
880	* 1 1 1 0x280000000..0x2ffffffff 0x300000000 2310-04-04..2378-04-22
881	* 1 1 0 0x300000000..0x37fffffff 0x300000000 2378-04-22..2446-05-10
882	*
883	* Note that previous versions of the kernel on 64-bit systems would
884	* incorrectly use extra epoch bits 1,1 for dates between 1901 and
885	* 1970. e2fsck will correct this, assuming that it is run on the
886	* affected filesystem before 2242.
887	*/
888
889	static inline __le32 ext4_encode_extra_time(struct timespec64 ts)
890	{
891	u32 extra = ((ts.tv_sec - (s32)ts.tv_sec) >> `32`) & EXT4_EPOCH_MASK;
892	return cpu_to_le32(extra \| (ts.tv_nsec << EXT4_EPOCH_BITS));
893	}
894
895	static inline struct timespec64 ext4_decode_extra_time(__le32 base,
896	__le32 extra)
897	{
898	struct timespec64 ts = { .tv_sec = (signed)le32_to_cpu(base) };
899
900	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
901	ts.tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << `32`;
902	ts.tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
903	return ts;
904	}
905
906	#define EXT4_INODE_SET_XTIME_VAL(xtime, inode, raw_inode, ts) \
907	do { \
908	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) { \
909	(raw_inode)->xtime = cpu_to_le32((ts).tv_sec); \
910	(raw_inode)->xtime ## _extra = ext4_encode_extra_time(ts); \
911	} else \
912	(raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (ts).tv_sec, S32_MIN, S32_MAX)); \
913	} while (0)
914
915	#define EXT4_INODE_SET_ATIME(inode, raw_inode) \
916	EXT4_INODE_SET_XTIME_VAL(i_atime, inode, raw_inode, inode_get_atime(inode))
917
918	#define EXT4_INODE_SET_MTIME(inode, raw_inode) \
919	EXT4_INODE_SET_XTIME_VAL(i_mtime, inode, raw_inode, inode_get_mtime(inode))
920
921	#define EXT4_INODE_SET_CTIME(inode, raw_inode) \
922	EXT4_INODE_SET_XTIME_VAL(i_ctime, inode, raw_inode, inode_get_ctime(inode))
923
924	#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \
925	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
926	EXT4_INODE_SET_XTIME_VAL(xtime, &((einode)->vfs_inode), \
927	raw_inode, (einode)->xtime)
928
929	#define EXT4_INODE_GET_XTIME_VAL(xtime, inode, raw_inode) \
930	(EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra) ? \
931	ext4_decode_extra_time((raw_inode)->xtime, \
932	(raw_inode)->xtime ## _extra) : \
933	(struct timespec64) { \
934	.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime) \
935	})
936
937	#define EXT4_INODE_GET_ATIME(inode, raw_inode) \
938	do { \
939	inode_set_atime_to_ts(inode, \
940	EXT4_INODE_GET_XTIME_VAL(i_atime, inode, raw_inode)); \
941	} while (0)
942
943	#define EXT4_INODE_GET_MTIME(inode, raw_inode) \
944	do { \
945	inode_set_mtime_to_ts(inode, \
946	EXT4_INODE_GET_XTIME_VAL(i_mtime, inode, raw_inode)); \
947	} while (0)
948
949	#define EXT4_INODE_GET_CTIME(inode, raw_inode) \
950	do { \
951	inode_set_ctime_to_ts(inode, \
952	EXT4_INODE_GET_XTIME_VAL(i_ctime, inode, raw_inode)); \
953	} while (0)
954
955	#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode) \
956	do { \
957	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
958	(einode)->xtime = \
959	EXT4_INODE_GET_XTIME_VAL(xtime, &(einode->vfs_inode), \
960	raw_inode); \
961	else \
962	(einode)->xtime = (struct timespec64){0, 0}; \
963	} while (0)
964
965	#define i_disk_version osd1.linux1.l_i_version
966
967	#if defined(__KERNEL__) \|\| defined(__linux__)
968	#define i_reserved1 osd1.linux1.l_i_reserved1
969	#define i_file_acl_high osd2.linux2.l_i_file_acl_high
970	#define i_blocks_high osd2.linux2.l_i_blocks_high
971	#define i_uid_low i_uid
972	#define i_gid_low i_gid
973	#define i_uid_high osd2.linux2.l_i_uid_high
974	#define i_gid_high osd2.linux2.l_i_gid_high
975	#define i_checksum_lo osd2.linux2.l_i_checksum_lo
976
977	#elif defined(__GNU__)
978
979	#define i_translator osd1.hurd1.h_i_translator
980	#define i_uid_high osd2.hurd2.h_i_uid_high
981	#define i_gid_high osd2.hurd2.h_i_gid_high
982	#define i_author osd2.hurd2.h_i_author
983
984	#elif defined(__masix__)
985
986	#define i_reserved1 osd1.masix1.m_i_reserved1
987	#define i_file_acl_high osd2.masix2.m_i_file_acl_high
988	#define i_reserved2 osd2.masix2.m_i_reserved2
989
990	#endif /* defined(__KERNEL__) \|\| defined(__linux__) */
991
992	#include "extents_status.h"
993	#include "fast_commit.h"
994
995	/*
996	* Lock subclasses for i_data_sem in the ext4_inode_info structure.
997	*
998	* These are needed to avoid lockdep false positives when we need to
999	* allocate blocks to the quota inode during ext4_map_blocks(), while
1000	* holding i_data_sem for a normal (non-quota) inode. Since we don't
1001	* do quota tracking for the quota inode, this avoids deadlock (as
1002	* well as infinite recursion, since it isn't turtles all the way
1003	* down...)
1004	*
1005	* I_DATA_SEM_NORMAL - Used for most inodes
1006	* I_DATA_SEM_OTHER - Used by move_inode.c for the second normal inode
1007	* where the second inode has larger inode number
1008	* than the first
1009	* I_DATA_SEM_QUOTA - Used for quota inodes only
1010	* I_DATA_SEM_EA - Used for ea_inodes only
1011	*/
1012	enum {
1013	I_DATA_SEM_NORMAL = `0`,
1014	I_DATA_SEM_OTHER,
1015	I_DATA_SEM_QUOTA,
1016	I_DATA_SEM_EA
1017	};
1018
1019
1020	/*
1021	* fourth extended file system inode data in memory
1022	*/
1023	struct ext4_inode_info {
1024	__le32 i_data[`15`]; / unconverted /
1025	__u32 i_dtime;
1026	ext4_fsblk_t i_file_acl;
1027
1028	/*
1029	* i_block_group is the number of the block group which contains
1030	* this file's inode. Constant across the lifetime of the inode,
1031	* it is used for making block allocation decisions - we try to
1032	* place a file's data blocks near its inode block, and new inodes
1033	* near to their parent directory's inode.
1034	*/
1035	ext4_group_t i_block_group;
1036	ext4_lblk_t i_dir_start_lookup;
1037	#if (BITS_PER_LONG < 64)
1038	unsigned long i_state_flags; / Dynamic state flags /
1039	#endif
1040	unsigned long i_flags;
1041
1042	/*
1043	* Extended attributes can be read independently of the main file
1044	* data. Taking i_rwsem even when reading would cause contention
1045	* between readers of EAs and writers of regular file data, so
1046	* instead we synchronize on xattr_sem when reading or changing
1047	* EAs.
1048	*/
1049	struct rw_semaphore xattr_sem;
1050
1051	/*
1052	* Inodes with EXT4_STATE_ORPHAN_FILE use i_orphan_idx. Otherwise
1053	* i_orphan is used.
1054	*/
1055	union {
1056	struct list_head i_orphan; / unlinked but open inodes /
1057	unsigned int i_orphan_idx; / Index in orphan file /
1058	};
1059
1060	/ Fast commit related info /
1061
1062	/ For tracking dentry create updates /
1063	struct list_head i_fc_dilist;
1064	struct list_head i_fc_list; /*
1065	* inodes that need fast commit
1066	* protected by sbi->s_fc_lock.
1067	*/
1068
1069	/ Start of lblk range that needs to be committed in this fast commit /
1070	ext4_lblk_t i_fc_lblk_start;
1071
1072	/ End of lblk range that needs to be committed in this fast commit /
1073	ext4_lblk_t i_fc_lblk_len;
1074
1075	spinlock_t i_raw_lock; / protects updates to the raw inode /
1076
1077	/ Fast commit wait queue for this inode /
1078	wait_queue_head_t i_fc_wait;
1079
1080	/*
1081	* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len
1082	* and inode's EXT4_FC_STATE_COMMITTING state bit.
1083	*/
1084	spinlock_t i_fc_lock;
1085
1086	/*
1087	* i_disksize keeps track of what the inode size is ON DISK, not
1088	* in memory. During truncate, i_size is set to the new size by
1089	* the VFS prior to calling ext4_truncate(), but the filesystem won't
1090	* set i_disksize to 0 until the truncate is actually under way.
1091	*
1092	* The intent is that i_disksize always represents the blocks which
1093	* are used by this file. This allows recovery to restart truncate
1094	* on orphans if we crash during truncate. We actually write i_disksize
1095	* into the on-disk inode when writing inodes out, instead of i_size.
1096	*
1097	* The only time when i_disksize and i_size may be different is when
1098	* a truncate is in progress. The only things which change i_disksize
1099	* are ext4_get_block (growth) and ext4_truncate (shrinkth).
1100	*/
1101	loff_t i_disksize;
1102
1103	/*
1104	* i_data_sem is for serialising ext4_truncate() against
1105	* ext4_getblock(). In the 2.4 ext2 design, great chunks of inode's
1106	* data tree are chopped off during truncate. We can't do that in
1107	* ext4 because whenever we perform intermediate commits during
1108	* truncate, the inode and all the metadata blocks must be in a
1109	* consistent state which allows truncation of the orphans to restart
1110	* during recovery. Hence we must fix the get_block-vs-truncate race
1111	* by other means, so we have i_data_sem.
1112	*/
1113	struct rw_semaphore i_data_sem;
1114	struct inode vfs_inode;
1115	struct jbd2_inode *jinode;
1116
1117	/*
1118	* File creation time. Its function is same as that of
1119	* struct timespec64 i_{a,c,m}time in the generic inode.
1120	*/
1121	struct timespec64 i_crtime;
1122
1123	/ mballoc /
1124	atomic_t i_prealloc_active;
1125
1126	/ allocation reservation info for delalloc /
1127	/ In case of bigalloc, this refer to clusters rather than blocks /
1128	unsigned int i_reserved_data_blocks;
1129	struct rb_root i_prealloc_node;
1130	rwlock_t i_prealloc_lock;
1131
1132	/ extents status tree /
1133	struct ext4_es_tree i_es_tree;
1134	rwlock_t i_es_lock;
1135	struct list_head i_es_list;
1136	unsigned int i_es_all_nr; / protected by i_es_lock /
1137	unsigned int i_es_shk_nr; / protected by i_es_lock /
1138	ext4_lblk_t i_es_shrink_lblk; / Offset where we start searching for*
1139	extents to shrink. Protected by
1140	i_es_lock /*
1141
1142	/ ialloc /
1143	ext4_group_t i_last_alloc_group;
1144
1145	/ pending cluster reservations for bigalloc file systems /
1146	struct ext4_pending_tree i_pending_tree;
1147
1148	/ on-disk additional length /
1149	__u16 i_extra_isize;
1150
1151	/ Indicate the inline data space. /
1152	u16 i_inline_off;
1153	u16 i_inline_size;
1154
1155	#ifdef CONFIG_QUOTA
1156	/ quota space reservation, managed internally by quota code /
1157	qsize_t i_reserved_quota;
1158	#endif
1159	spinlock_t i_block_reservation_lock;
1160
1161	/ Lock protecting lists below /
1162	spinlock_t i_completed_io_lock;
1163	/*
1164	* Completed IOs that need unwritten extents handling and have
1165	* transaction reserved
1166	*/
1167	struct list_head i_rsv_conversion_list;
1168	struct work_struct i_rsv_conversion_work;
1169
1170	/*
1171	* Transactions that contain inode's metadata needed to complete
1172	* fsync and fdatasync, respectively.
1173	*/
1174	tid_t i_sync_tid;
1175	tid_t i_datasync_tid;
1176
1177	#ifdef CONFIG_QUOTA
1178	struct dquot __rcu *i_dquot[MAXQUOTAS];
1179	#endif
1180
1181	/ Precomputed uuid+inum+igen checksum for seeding inode checksums /
1182	__u32 i_csum_seed;
1183
1184	kprojid_t i_projid;
1185
1186	#ifdef CONFIG_FS_ENCRYPTION
1187	struct fscrypt_inode_info *i_crypt_info;
1188	#endif
1189
1190	#ifdef CONFIG_FS_VERITY
1191	struct fsverity_info *i_verity_info;
1192	#endif
1193	};
1194
1195	/*
1196	* File system states
1197	*/
1198	#define EXT4_VALID_FS 0x0001 /* Unmounted cleanly */
1199	#define EXT4_ERROR_FS 0x0002 /* Errors detected */
1200	#define EXT4_ORPHAN_FS 0x0004 /* Orphans being recovered */
1201	#define EXT4_FC_REPLAY 0x0020 /* Fast commit replay ongoing */
1202
1203	/*
1204	* Misc. filesystem flags
1205	*/
1206	#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
1207	#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
1208	#define EXT2_FLAGS_TEST_FILESYS 0x0004 /* to test development code */
1209
1210	/*
1211	* Mount flags set via mount options or defaults
1212	*/
1213	#define EXT4_MOUNT_NO_MBCACHE 0x00001 /* Do not use mbcache */
1214	#define EXT4_MOUNT_GRPID 0x00004 /* Create files with directory's group */
1215	#define EXT4_MOUNT_DEBUG 0x00008 /* Some debugging messages */
1216	#define EXT4_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */
1217	#define EXT4_MOUNT_ERRORS_RO 0x00020 /* Remount fs ro on errors */
1218	#define EXT4_MOUNT_ERRORS_PANIC 0x00040 /* Panic on errors */
1219	#define EXT4_MOUNT_ERRORS_MASK 0x00070
1220	#define EXT4_MOUNT_MINIX_DF 0x00080 /* Mimics the Minix statfs */
1221	#define EXT4_MOUNT_NOLOAD 0x00100 /* Don't use existing journal*/
1222	#ifdef CONFIG_FS_DAX
1223	#define EXT4_MOUNT_DAX_ALWAYS 0x00200 /* Direct Access */
1224	#else
1225	#define EXT4_MOUNT_DAX_ALWAYS 0
1226	#endif
1227	#define EXT4_MOUNT_DATA_FLAGS 0x00C00 /* Mode for data writes: */
1228	#define EXT4_MOUNT_JOURNAL_DATA 0x00400 /* Write data to journal */
1229	#define EXT4_MOUNT_ORDERED_DATA 0x00800 /* Flush data before commit */
1230	#define EXT4_MOUNT_WRITEBACK_DATA 0x00C00 /* No data ordering */
1231	#define EXT4_MOUNT_UPDATE_JOURNAL 0x01000 /* Update the journal format */
1232	#define EXT4_MOUNT_NO_UID32 0x02000 /* Disable 32-bit UIDs */
1233	#define EXT4_MOUNT_XATTR_USER 0x04000 /* Extended user attributes */
1234	#define EXT4_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */
1235	#define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */
1236	#define EXT4_MOUNT_BARRIER 0x20000 /* Use block barriers */
1237	#define EXT4_MOUNT_QUOTA 0x40000 /* Some quota option set */
1238	#define EXT4_MOUNT_USRQUOTA 0x80000 /* "old" user quota,
1239	* enable enforcement for hidden
1240	* quota files */
1241	#define EXT4_MOUNT_GRPQUOTA 0x100000 /* "old" group quota, enable
1242	* enforcement for hidden quota
1243	* files */
1244	#define EXT4_MOUNT_PRJQUOTA 0x200000 /* Enable project quota
1245	* enforcement */
1246	#define EXT4_MOUNT_DIOREAD_NOLOCK 0x400000 /* Enable support for dio read nolocking */
1247	#define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */
1248	#define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
1249	#define EXT4_MOUNT_WARN_ON_ERROR 0x2000000 /* Trigger WARN_ON on error */
1250	#define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
1251	#define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */
1252	#define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */
1253	#define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */
1254	#define EXT4_MOUNT_DISCARD 0x40000000 /* Issue DISCARD requests */
1255	#define EXT4_MOUNT_INIT_INODE_TABLE 0x80000000 /* Initialize uninitialized itables */
1256
1257	/*
1258	* Mount flags set either automatically (could not be set by mount option)
1259	* based on per file system feature or property or in special cases such as
1260	* distinguishing between explicit mount option definition and default.
1261	*/
1262	#define EXT4_MOUNT2_EXPLICIT_DELALLOC 0x00000001 /* User explicitly
1263	specified delalloc */
1264	#define EXT4_MOUNT2_STD_GROUP_SIZE 0x00000002 /* We have standard group
1265	size of blocksize * 8
1266	blocks */
1267	#define EXT4_MOUNT2_HURD_COMPAT 0x00000004 /* Support HURD-castrated
1268	file systems */
1269	#define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM 0x00000008 /* User explicitly
1270	specified journal checksum */
1271
1272	#define EXT4_MOUNT2_JOURNAL_FAST_COMMIT 0x00000010 /* Journal fast commit */
1273	#define EXT4_MOUNT2_DAX_NEVER 0x00000020 /* Do not allow Direct Access */
1274	#define EXT4_MOUNT2_DAX_INODE 0x00000040 /* For printing options only */
1275	#define EXT4_MOUNT2_MB_OPTIMIZE_SCAN 0x00000080 /* Optimize group
1276	* scanning in mballoc
1277	*/
1278	#define EXT4_MOUNT2_ABORT 0x00000100 /* Abort filesystem */
1279
1280	#define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \
1281	~EXT4_MOUNT_##opt
1282	#define set_opt(sb, opt) EXT4_SB(sb)->s_mount_opt \|= \
1283	EXT4_MOUNT_##opt
1284	#define test_opt(sb, opt) (EXT4_SB(sb)->s_mount_opt & \
1285	EXT4_MOUNT_##opt)
1286
1287	#define clear_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 &= \
1288	~EXT4_MOUNT2_##opt
1289	#define set_opt2(sb, opt) EXT4_SB(sb)->s_mount_opt2 \|= \
1290	EXT4_MOUNT2_##opt
1291	#define test_opt2(sb, opt) (EXT4_SB(sb)->s_mount_opt2 & \
1292	EXT4_MOUNT2_##opt)
1293
1294	#define ext4_test_and_set_bit __test_and_set_bit_le
1295	#define ext4_set_bit __set_bit_le
1296	#define ext4_test_and_clear_bit __test_and_clear_bit_le
1297	#define ext4_clear_bit __clear_bit_le
1298	#define ext4_test_bit test_bit_le
1299	#define ext4_find_next_zero_bit find_next_zero_bit_le
1300	#define ext4_find_next_bit find_next_bit_le
1301
1302	extern void mb_set_bits(void bm, int* cur, int len);
1303
1304	/*
1305	* Maximal mount counts between two filesystem checks
1306	*/
1307	#define EXT4_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
1308	#define EXT4_DFL_CHECKINTERVAL 0 /* Don't use interval check */
1309
1310	/*
1311	* Behaviour when detecting errors
1312	*/
1313	#define EXT4_ERRORS_CONTINUE 1 /* Continue execution */
1314	#define EXT4_ERRORS_RO 2 /* Remount fs read-only */
1315	#define EXT4_ERRORS_PANIC 3 /* Panic */
1316	#define EXT4_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE
1317
1318	/ Metadata checksum algorithm codes /
1319	#define EXT4_CRC32C_CHKSUM 1
1320
1321	#define EXT4_LABEL_MAX 16
1322
1323	/*
1324	* Structure of the super block
1325	*/
1326	struct ext4_super_block {
1327	/00/ __le32 s_inodes_count; / Inodes count /
1328	__le32 s_blocks_count_lo; / Blocks count /
1329	__le32 s_r_blocks_count_lo; / Reserved blocks count /
1330	__le32 s_free_blocks_count_lo; / Free blocks count /
1331	/10/ __le32 s_free_inodes_count; / Free inodes count /
1332	__le32 s_first_data_block; / First Data Block /
1333	__le32 s_log_block_size; / Block size /
1334	__le32 s_log_cluster_size; / Allocation cluster size /
1335	/20/ __le32 s_blocks_per_group; / # Blocks per group /
1336	__le32 s_clusters_per_group; / # Clusters per group /
1337	__le32 s_inodes_per_group; / # Inodes per group /
1338	__le32 s_mtime; / Mount time /
1339	/30/ __le32 s_wtime; / Write time /
1340	__le16 s_mnt_count; / Mount count /
1341	__le16 s_max_mnt_count; / Maximal mount count /
1342	__le16 s_magic; / Magic signature /
1343	__le16 s_state; / File system state /
1344	__le16 s_errors; / Behaviour when detecting errors /
1345	__le16 s_minor_rev_level; / minor revision level /
1346	/40/ __le32 s_lastcheck; / time of last check /
1347	__le32 s_checkinterval; / max. time between checks /
1348	__le32 s_creator_os; / OS /
1349	__le32 s_rev_level; / Revision level /
1350	/50/ __le16 s_def_resuid; / Default uid for reserved blocks /
1351	__le16 s_def_resgid; / Default gid for reserved blocks /
1352	/*
1353	* These fields are for EXT4_DYNAMIC_REV superblocks only.
1354	*
1355	* Note: the difference between the compatible feature set and
1356	* the incompatible feature set is that if there is a bit set
1357	* in the incompatible feature set that the kernel doesn't
1358	* know about, it should refuse to mount the filesystem.
1359	*
1360	* e2fsck's requirements are more strict; if it doesn't know
1361	* about a feature in either the compatible or incompatible
1362	* feature set, it must abort and not try to meddle with
1363	* things it doesn't understand...
1364	*/
1365	__le32 s_first_ino; / First non-reserved inode /
1366	__le16 s_inode_size; / size of inode structure /
1367	__le16 s_block_group_nr; / block group # of this superblock /
1368	__le32 s_feature_compat; / compatible feature set /
1369	/60/ __le32 s_feature_incompat; / incompatible feature set /
1370	__le32 s_feature_ro_compat; / readonly-compatible feature set /
1371	/68/ __u8 s_uuid[`16`]; / 128-bit uuid for volume /
1372	/78/ char s_volume_name[EXT4_LABEL_MAX] __nonstring; / volume name /
1373	/88/ char s_last_mounted[`64`] __nonstring; / directory where last mounted /
1374	/C8/ __le32 s_algorithm_usage_bitmap; / For compression /
1375	/*
1376	* Performance hints. Directory preallocation should only
1377	* happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1378	*/
1379	__u8 s_prealloc_blocks; / Nr of blocks to try to preallocate/
1380	__u8 s_prealloc_dir_blocks; / Nr to preallocate for dirs /
1381	__le16 s_reserved_gdt_blocks; / Per group desc for online growth /
1382	/*
1383	* Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1384	*/
1385	/D0/ __u8 s_journal_uuid[`16`]; / uuid of journal superblock /
1386	/E0/ __le32 s_journal_inum; / inode number of journal file /
1387	__le32 s_journal_dev; / device number of journal file /
1388	__le32 s_last_orphan; / start of list of inodes to delete /
1389	__le32 s_hash_seed[`4`]; / HTREE hash seed /
1390	__u8 s_def_hash_version; / Default hash version to use /
1391	__u8 s_jnl_backup_type;
1392	__le16 s_desc_size; / size of group descriptor /
1393	/100/ __le32 s_default_mount_opts;
1394	__le32 s_first_meta_bg; / First metablock block group /
1395	__le32 s_mkfs_time; / When the filesystem was created /
1396	__le32 s_jnl_blocks[`17`]; / Backup of the journal inode /
1397	/ 64bit support valid if EXT4_FEATURE_INCOMPAT_64BIT /
1398	/150/ __le32 s_blocks_count_hi; / Blocks count /
1399	__le32 s_r_blocks_count_hi; / Reserved blocks count /
1400	__le32 s_free_blocks_count_hi; / Free blocks count /
1401	__le16 s_min_extra_isize; / All inodes have at least # bytes /
1402	__le16 s_want_extra_isize; / New inodes should reserve # bytes /
1403	__le32 s_flags; / Miscellaneous flags /
1404	__le16 s_raid_stride; / RAID stride /
1405	__le16 s_mmp_update_interval; / # seconds to wait in MMP checking /
1406	__le64 s_mmp_block; / Block for multi-mount protection /
1407	__le32 s_raid_stripe_width; / blocks on all data disks (Nstride)/*
1408	__u8 s_log_groups_per_flex; / FLEX_BG group size /
1409	__u8 s_checksum_type; / metadata checksum algorithm used /
1410	__u8 s_encryption_level; / versioning level for encryption /
1411	__u8 s_reserved_pad; / Padding to next 32bits /
1412	__le64 s_kbytes_written; / nr of lifetime kilobytes written /
1413	__le32 s_snapshot_inum; / Inode number of active snapshot /
1414	__le32 s_snapshot_id; / sequential ID of active snapshot /
1415	__le64 s_snapshot_r_blocks_count; / reserved blocks for active*
1416	snapshot's future use /*
1417	__le32 s_snapshot_list; / inode number of the head of the*
1418	on-disk snapshot list /*
1419	#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1420	__le32 s_error_count; / number of fs errors /
1421	__le32 s_first_error_time; / first time an error happened /
1422	__le32 s_first_error_ino; / inode involved in first error /
1423	__le64 s_first_error_block; / block involved of first error /
1424	__u8 s_first_error_func[`32`] __nonstring; / function where the error happened /
1425	__le32 s_first_error_line; / line number where error happened /
1426	__le32 s_last_error_time; / most recent time of an error /
1427	__le32 s_last_error_ino; / inode involved in last error /
1428	__le32 s_last_error_line; / line number where error happened /
1429	__le64 s_last_error_block; / block involved of last error /
1430	__u8 s_last_error_func[`32`] __nonstring; / function where the error happened /
1431	#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1432	__u8 s_mount_opts[`64`];
1433	__le32 s_usr_quota_inum; / inode for tracking user quota /
1434	__le32 s_grp_quota_inum; / inode for tracking group quota /
1435	__le32 s_overhead_clusters; / overhead blocks/clusters in fs /
1436	__le32 s_backup_bgs[`2`]; / groups with sparse_super2 SBs /
1437	__u8 s_encrypt_algos[`4`]; / Encryption algorithms in use /
1438	__u8 s_encrypt_pw_salt[`16`]; / Salt used for string2key algorithm /
1439	__le32 s_lpf_ino; / Location of the lost+found inode /
1440	__le32 s_prj_quota_inum; / inode for tracking project quota /
1441	__le32 s_checksum_seed; / crc32c(uuid) if csum_seed set /
1442	__u8 s_wtime_hi;
1443	__u8 s_mtime_hi;
1444	__u8 s_mkfs_time_hi;
1445	__u8 s_lastcheck_hi;
1446	__u8 s_first_error_time_hi;
1447	__u8 s_last_error_time_hi;
1448	__u8 s_first_error_errcode;
1449	__u8 s_last_error_errcode;
1450	__le16 s_encoding; / Filename charset encoding /
1451	__le16 s_encoding_flags; / Filename charset encoding flags /
1452	__le32 s_orphan_file_inum; / Inode for tracking orphan inodes /
1453	__le16 s_def_resuid_hi;
1454	__le16 s_def_resgid_hi;
1455	__le32 s_reserved[`93`]; / Padding to the end of the block /
1456	__le32 s_checksum; / crc32c(superblock) /
1457	};
1458
1459	#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1460
1461	#ifdef __KERNEL__
1462
1463	/ Number of quota types we support /
1464	#define EXT4_MAXQUOTAS 3
1465
1466	#define EXT4_ENC_UTF8_12_1 1
1467
1468	/ Types of ext4 journal triggers /
1469	enum ext4_journal_trigger_type {
1470	EXT4_JTR_ORPHAN_FILE,
1471	EXT4_JTR_NONE / This must be the last entry for indexing to work! /
1472	};
1473
1474	#define EXT4_JOURNAL_TRIGGER_COUNT EXT4_JTR_NONE
1475
1476	struct ext4_journal_trigger {
1477	struct jbd2_buffer_trigger_type tr_triggers;
1478	struct super_block *sb;
1479	};
1480
1481	static inline struct ext4_journal_trigger *EXT4_TRIGGER(
1482	struct jbd2_buffer_trigger_type *trigger)
1483	{
1484	return container_of(trigger, struct ext4_journal_trigger, tr_triggers);
1485	}
1486
1487	#define EXT4_ORPHAN_BLOCK_MAGIC 0x0b10ca04
1488
1489	/ Structure at the tail of orphan block /
1490	struct ext4_orphan_block_tail {
1491	__le32 ob_magic;
1492	__le32 ob_checksum;
1493	};
1494
1495	static inline int ext4_inodes_per_orphan_block(struct super_block *sb)
1496	{
1497	return (sb->s_blocksize - sizeof(struct ext4_orphan_block_tail)) /
1498	sizeof(u32);
1499	}
1500
1501	struct ext4_orphan_block {
1502	atomic_t ob_free_entries; / Number of free orphan entries in block /
1503	struct buffer_head ob_bh; /* Buffer for orphan block /
1504	};
1505
1506	/*
1507	* Info about orphan file.
1508	*/
1509	struct ext4_orphan_info {
1510	int of_blocks; / Number of orphan blocks in a file /
1511	__u32 of_csum_seed; / Checksum seed for orphan file /
1512	struct ext4_orphan_block of_binfo; /* Array with info about orphan*
1513	* file blocks */
1514	};
1515
1516	/*
1517	* fourth extended-fs super-block data in memory
1518	*/
1519	struct ext4_sb_info {
1520	unsigned long s_desc_size; / Size of a group descriptor in bytes /
1521	unsigned long s_inodes_per_block;/ Number of inodes per block /
1522	unsigned long s_blocks_per_group;/ Number of blocks in a group /
1523	unsigned long s_clusters_per_group; / Number of clusters in a group /
1524	unsigned long s_inodes_per_group;/ Number of inodes in a group /
1525	unsigned long s_itb_per_group; / Number of inode table blocks per group /
1526	unsigned long s_gdb_count; / Number of group descriptor blocks /
1527	unsigned long s_desc_per_block; / Number of group descriptors per block /
1528	ext4_group_t s_groups_count; / Number of groups in the fs /
1529	ext4_group_t s_blockfile_groups;/ Groups acceptable for non-extent files /
1530	unsigned long s_overhead; / # of fs overhead clusters /
1531	unsigned int s_cluster_ratio; / Number of blocks per cluster /
1532	unsigned int s_cluster_bits; / log2 of s_cluster_ratio /
1533	loff_t s_bitmap_maxbytes; / max bytes for bitmap files /
1534	struct buffer_head * s_sbh; / Buffer containing the super block /
1535	struct ext4_super_block s_es; /* Pointer to the super block in the buffer /
1536	/ Array of bh's for the block group descriptors /
1537	struct buffer_head * __rcu *s_group_desc;
1538	unsigned int s_mount_opt;
1539	unsigned int s_mount_opt2;
1540	unsigned long s_mount_flags;
1541	unsigned int s_def_mount_opt;
1542	unsigned int s_def_mount_opt2;
1543	ext4_fsblk_t s_sb_block;
1544	atomic64_t s_resv_clusters;
1545	kuid_t s_resuid;
1546	kgid_t s_resgid;
1547	unsigned short s_mount_state;
1548	unsigned short s_pad;
1549	int s_addr_per_block_bits;
1550	int s_desc_per_block_bits;
1551	int s_inode_size;
1552	int s_first_ino;
1553	unsigned int s_inode_readahead_blks;
1554	unsigned int s_inode_goal;
1555	u32 s_hash_seed[`4`];
1556	int s_def_hash_version;
1557	int s_hash_unsigned; / 3 if hash should be unsigned, 0 if not /
1558	struct percpu_counter s_freeclusters_counter;
1559	struct percpu_counter s_freeinodes_counter;
1560	struct percpu_counter s_dirs_counter;
1561	struct percpu_counter s_dirtyclusters_counter;
1562	struct percpu_counter s_sra_exceeded_retry_limit;
1563	struct blockgroup_lock *s_blockgroup_lock;
1564	struct proc_dir_entry *s_proc;
1565	struct kobject s_kobj;
1566	struct completion s_kobj_unregister;
1567	struct super_block *s_sb;
1568	struct buffer_head *s_mmp_bh;
1569
1570	/ Journaling /
1571	struct journal_s *s_journal;
1572	unsigned long s_ext4_flags; / Ext4 superblock flags /
1573	struct mutex s_orphan_lock; / Protects on disk list changes /
1574	struct list_head s_orphan; / List of orphaned inodes in on disk*
1575	list /*
1576	struct ext4_orphan_info s_orphan_info;
1577	unsigned long s_commit_interval;
1578	u32 s_max_batch_time;
1579	u32 s_min_batch_time;
1580	struct file *s_journal_bdev_file;
1581	#ifdef CONFIG_QUOTA
1582	/ Names of quota files with journalled quota /
1583	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1584	int s_jquota_fmt; / Format of quota to use /
1585	#endif
1586	unsigned int s_want_extra_isize; / New inodes should reserve # bytes /
1587	struct ext4_system_blocks __rcu *s_system_blks;
1588
1589	#ifdef EXTENTS_STATS
1590	/ ext4 extents stats /
1591	unsigned long s_ext_min;
1592	unsigned long s_ext_max;
1593	unsigned long s_depth_max;
1594	spinlock_t s_ext_stats_lock;
1595	unsigned long s_ext_blocks;
1596	unsigned long s_ext_extents;
1597	#endif
1598
1599	/ for buddy allocator /
1600	struct ext4_group_info ** __rcu *s_group_info;
1601	struct inode *s_buddy_cache;
1602	spinlock_t s_md_lock;
1603	unsigned short *s_mb_offsets;
1604	unsigned int *s_mb_maxs;
1605	unsigned int s_group_info_size;
1606	atomic_t s_mb_free_pending;
1607	struct list_head s_freed_data_list[`2`]; / List of blocks to be freed*
1608	after commit completed /*
1609	struct list_head s_discard_list;
1610	struct work_struct s_discard_work;
1611	atomic_t s_retry_alloc_pending;
1612	struct xarray *s_mb_avg_fragment_size;
1613	struct xarray *s_mb_largest_free_orders;
1614
1615	/ tunables /
1616	unsigned long s_stripe;
1617	unsigned int s_mb_max_linear_groups;
1618	unsigned int s_mb_stream_request;
1619	unsigned int s_mb_max_to_scan;
1620	unsigned int s_mb_min_to_scan;
1621	unsigned int s_mb_stats;
1622	unsigned int s_mb_order2_reqs;
1623	unsigned int s_mb_group_prealloc;
1624	unsigned int s_max_dir_size_kb;
1625	unsigned int s_mb_prefetch;
1626	unsigned int s_mb_prefetch_limit;
1627	unsigned int s_mb_best_avail_max_trim_order;
1628	unsigned int s_sb_update_sec;
1629	unsigned int s_sb_update_kb;
1630
1631	/ where last allocation was done - for stream allocation /
1632	ext4_group_t *s_mb_last_groups;
1633	unsigned int s_mb_nr_global_goals;
1634
1635	/ stats for buddy allocator /
1636	atomic_t s_bal_reqs; / number of reqs with len > 1 /
1637	atomic_t s_bal_success; / we found long enough chunks /
1638	atomic_t s_bal_allocated; / in blocks /
1639	atomic_t s_bal_ex_scanned; / total extents scanned /
1640	atomic_t s_bal_cX_ex_scanned[EXT4_MB_NUM_CRS]; / total extents scanned /
1641	atomic_t s_bal_groups_scanned; / number of groups scanned /
1642	atomic_t s_bal_goals; / goal hits /
1643	atomic_t s_bal_stream_goals; / stream allocation global goal hits /
1644	atomic_t s_bal_len_goals; / len goal hits /
1645	atomic_t s_bal_breaks; / too long searches /
1646	atomic_t s_bal_2orders; / 2^order hits /
1647	atomic64_t s_bal_cX_groups_considered[EXT4_MB_NUM_CRS];
1648	atomic64_t s_bal_cX_hits[EXT4_MB_NUM_CRS];
1649	atomic64_t s_bal_cX_failed[EXT4_MB_NUM_CRS]; / cX loop didn't find blocks /
1650	atomic_t s_mb_buddies_generated; / number of buddies generated /
1651	atomic64_t s_mb_generation_time;
1652	atomic_t s_mb_lost_chunks;
1653	atomic_t s_mb_preallocated;
1654	atomic_t s_mb_discarded;
1655	atomic_t s_lock_busy;
1656
1657	/ locality groups /
1658	struct ext4_locality_group __percpu *s_locality_groups;
1659
1660	/ for write statistics /
1661	unsigned long s_sectors_written_start;
1662	u64 s_kbytes_written;
1663
1664	/ the size of zero-out chunk /
1665	unsigned int s_extent_max_zeroout_kb;
1666
1667	unsigned int s_log_groups_per_flex;
1668	struct flex_groups * __rcu *s_flex_groups;
1669	ext4_group_t s_flex_groups_allocated;
1670
1671	/ workqueue for reserved extent conversions (buffered io) /
1672	struct workqueue_struct *rsv_conversion_wq;
1673
1674	/ timer for periodic error stats printing /
1675	struct timer_list s_err_report;
1676
1677	/ Lazy inode table initialization info /
1678	struct ext4_li_request *s_li_request;
1679	/ Wait multiplier for lazy initialization thread /
1680	unsigned int s_li_wait_mult;
1681
1682	/ Kernel thread for multiple mount protection /
1683	struct task_struct *s_mmp_tsk;
1684
1685	/ record the last minlen when FITRIM is called. /
1686	unsigned long s_last_trim_minblks;
1687
1688	/ Precomputed FS UUID checksum for seeding other checksums /
1689	__u32 s_csum_seed;
1690
1691	/ Reclaim extents from extent status tree /
1692	struct shrinker *s_es_shrinker;
1693	struct list_head s_es_list; / List of inodes with reclaimable extents /
1694	long s_es_nr_inode;
1695	struct ext4_es_stats s_es_stats;
1696	struct mb_cache *s_ea_block_cache;
1697	struct mb_cache *s_ea_inode_cache;
1698	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1699
1700	/ Journal triggers for checksum computation /
1701	struct ext4_journal_trigger s_journal_triggers[EXT4_JOURNAL_TRIGGER_COUNT];
1702
1703	/ Ratelimit ext4 messages. /
1704	struct ratelimit_state s_err_ratelimit_state;
1705	struct ratelimit_state s_warning_ratelimit_state;
1706	struct ratelimit_state s_msg_ratelimit_state;
1707	atomic_t s_warning_count;
1708	atomic_t s_msg_count;
1709
1710	/ Encryption policy for '-o test_dummy_encryption' /
1711	struct fscrypt_dummy_policy s_dummy_enc_policy;
1712
1713	/*
1714	* Barrier between writepages ops and changing any inode's JOURNAL_DATA
1715	* or EXTENTS flag or between writepages ops and changing DELALLOC or
1716	* DIOREAD_NOLOCK mount options on remount.
1717	*/
1718	struct percpu_rw_semaphore s_writepages_rwsem;
1719	struct dax_device *s_daxdev;
1720	u64 s_dax_part_off;
1721	#ifdef CONFIG_EXT4_DEBUG
1722	unsigned long s_simulate_fail;
1723	#endif
1724	/ Record the errseq of the backing block device /
1725	errseq_t s_bdev_wb_err;
1726	spinlock_t s_bdev_wb_lock;
1727
1728	/ Information about errors that happened during this mount /
1729	spinlock_t s_error_lock;
1730	int s_add_error_count;
1731	int s_first_error_code;
1732	__u32 s_first_error_line;
1733	__u32 s_first_error_ino;
1734	__u64 s_first_error_block;
1735	const char *s_first_error_func;
1736	time64_t s_first_error_time;
1737	int s_last_error_code;
1738	__u32 s_last_error_line;
1739	__u32 s_last_error_ino;
1740	__u64 s_last_error_block;
1741	const char *s_last_error_func;
1742	time64_t s_last_error_time;
1743	/*
1744	* If we are in a context where we cannot update the on-disk
1745	* superblock, we queue the work here. This is used to update
1746	* the error information in the superblock, and for periodic
1747	* updates of the superblock called from the commit callback
1748	* function.
1749	*/
1750	struct work_struct s_sb_upd_work;
1751
1752	/ Atomic write unit values in bytes /
1753	unsigned int s_awu_min;
1754	unsigned int s_awu_max;
1755
1756	/ Ext4 fast commit sub transaction ID /
1757	atomic_t s_fc_subtid;
1758
1759	/*
1760	* After commit starts, the main queue gets locked, and the further
1761	* updates get added in the staging queue.
1762	*/
1763	#define FC_Q_MAIN 0
1764	#define FC_Q_STAGING 1
1765	struct list_head s_fc_q[`2`]; / Inodes staged for fast commit*
1766	* that have data changes in them.
1767	*/
1768	struct list_head s_fc_dentry_q[`2`]; / directory entry updates /
1769	unsigned int s_fc_bytes;
1770	/*
1771	* Main fast commit lock. This lock protects accesses to the
1772	* following fields:
1773	* ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1774	*/
1775	struct mutex s_fc_lock;
1776	struct buffer_head *s_fc_bh;
1777	struct ext4_fc_stats s_fc_stats;
1778	tid_t s_fc_ineligible_tid;
1779	#ifdef CONFIG_EXT4_DEBUG
1780	int s_fc_debug_max_replay;
1781	#endif
1782	struct ext4_fc_replay_state s_fc_replay_state;
1783	};
1784
1785	static inline struct ext4_sb_info EXT4_SB(struct* super_block *sb)
1786	{
1787	return sb->s_fs_info;
1788	}
1789	static inline struct ext4_inode_info EXT4_I(struct* inode *inode)
1790	{
1791	return container_of(inode, struct ext4_inode_info, vfs_inode);
1792	}
1793
1794	static inline int ext4_writepages_down_read(struct super_block *sb)
1795	{
1796	percpu_down_read(sem: &EXT4_SB(sb)->s_writepages_rwsem);
1797	return memalloc_nofs_save();
1798	}
1799
1800	static inline void ext4_writepages_up_read(struct super_block sb, int* ctx)
1801	{
1802	memalloc_nofs_restore(flags: ctx);
1803	percpu_up_read(sem: &EXT4_SB(sb)->s_writepages_rwsem);
1804	}
1805
1806	static inline int ext4_writepages_down_write(struct super_block *sb)
1807	{
1808	percpu_down_write(&EXT4_SB(sb)->s_writepages_rwsem);
1809	return memalloc_nofs_save();
1810	}
1811
1812	static inline void ext4_writepages_up_write(struct super_block sb, int* ctx)
1813	{
1814	memalloc_nofs_restore(flags: ctx);
1815	percpu_up_write(&EXT4_SB(sb)->s_writepages_rwsem);
1816	}
1817
1818	static inline int ext4_valid_inum(struct super_block sb, unsigned* long ino)
1819	{
1820	return ino == EXT4_ROOT_INO \|\|
1821	(ino >= EXT4_FIRST_INO(sb) &&
1822	ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1823	}
1824
1825	static inline int ext4_get_resuid(struct ext4_super_block *es)
1826	{
1827	return le16_to_cpu(es->s_def_resuid) \|
1828	le16_to_cpu(es->s_def_resuid_hi) << `16`;
1829	}
1830
1831	static inline int ext4_get_resgid(struct ext4_super_block *es)
1832	{
1833	return le16_to_cpu(es->s_def_resgid) \|
1834	le16_to_cpu(es->s_def_resgid_hi) << `16`;
1835	}
1836
1837	/*
1838	* Returns: sbi->field[index]
1839	* Used to access an array element from the following sbi fields which require
1840	* rcu protection to avoid dereferencing an invalid pointer due to reassignment
1841	* - s_group_desc
1842	* - s_group_info
1843	* - s_flex_group
1844	*/
1845	#define sbi_array_rcu_deref(sbi, field, index) \
1846	({ \
1847	typeof(*((sbi)->field)) _v; \
1848	rcu_read_lock(); \
1849	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index]; \
1850	rcu_read_unlock(); \
1851	_v; \
1852	})
1853
1854	/*
1855	* run-time mount flags
1856	*/
1857	enum {
1858	EXT4_MF_MNTDIR_SAMPLED,
1859	EXT4_MF_FC_INELIGIBLE, / Fast commit ineligible /
1860	EXT4_MF_JOURNAL_DESTROY / Journal is in process of destroying /
1861	};
1862
1863	static inline void ext4_set_mount_flag(struct super_block sb, int* bit)
1864	{
1865	set_bit(nr: bit, addr: &EXT4_SB(sb)->s_mount_flags);
1866	}
1867
1868	static inline void ext4_clear_mount_flag(struct super_block sb, int* bit)
1869	{
1870	clear_bit(nr: bit, addr: &EXT4_SB(sb)->s_mount_flags);
1871	}
1872
1873	static inline int ext4_test_mount_flag(struct super_block sb, int* bit)
1874	{
1875	return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1876	}
1877
1878
1879	/*
1880	* Simulate_fail codes
1881	*/
1882	#define EXT4_SIM_BBITMAP_EIO 1
1883	#define EXT4_SIM_BBITMAP_CRC 2
1884	#define EXT4_SIM_IBITMAP_EIO 3
1885	#define EXT4_SIM_IBITMAP_CRC 4
1886	#define EXT4_SIM_INODE_EIO 5
1887	#define EXT4_SIM_INODE_CRC 6
1888	#define EXT4_SIM_DIRBLOCK_EIO 7
1889	#define EXT4_SIM_DIRBLOCK_CRC 8
1890
1891	static inline bool ext4_simulate_fail(struct super_block *sb,
1892	unsigned long code)
1893	{
1894	#ifdef CONFIG_EXT4_DEBUG
1895	struct ext4_sb_info *sbi = EXT4_SB(sb);
1896
1897	if (unlikely(sbi->s_simulate_fail == code)) {
1898	sbi->s_simulate_fail = `0`;
1899	return true;
1900	}
1901	#endif
1902	return false;
1903	}
1904
1905	/*
1906	* Error number codes for s_{first,last}_error_errno
1907	*
1908	* Linux errno numbers are architecture specific, so we need to translate
1909	* them into something which is architecture independent. We don't define
1910	* codes for all errno's; just the ones which are most likely to be the cause
1911	* of an ext4_error() call.
1912	*/
1913	#define EXT4_ERR_UNKNOWN 1
1914	#define EXT4_ERR_EIO 2
1915	#define EXT4_ERR_ENOMEM 3
1916	#define EXT4_ERR_EFSBADCRC 4
1917	#define EXT4_ERR_EFSCORRUPTED 5
1918	#define EXT4_ERR_ENOSPC 6
1919	#define EXT4_ERR_ENOKEY 7
1920	#define EXT4_ERR_EROFS 8
1921	#define EXT4_ERR_EFBIG 9
1922	#define EXT4_ERR_EEXIST 10
1923	#define EXT4_ERR_ERANGE 11
1924	#define EXT4_ERR_EOVERFLOW 12
1925	#define EXT4_ERR_EBUSY 13
1926	#define EXT4_ERR_ENOTDIR 14
1927	#define EXT4_ERR_ENOTEMPTY 15
1928	#define EXT4_ERR_ESHUTDOWN 16
1929	#define EXT4_ERR_EFAULT 17
1930
1931	/*
1932	* Inode dynamic state flags
1933	*/
1934	enum {
1935	EXT4_STATE_NEW, / inode is newly created /
1936	EXT4_STATE_XATTR, / has in-inode xattrs /
1937	EXT4_STATE_NO_EXPAND, / No space for expansion /
1938	EXT4_STATE_DA_ALLOC_CLOSE, / Alloc DA blks on close /
1939	EXT4_STATE_EXT_MIGRATE, / Inode is migrating /
1940	EXT4_STATE_NEWENTRY, / File just added to dir /
1941	EXT4_STATE_MAY_INLINE_DATA, / may have in-inode data /
1942	EXT4_STATE_EXT_PRECACHED, / extents have been precached /
1943	EXT4_STATE_LUSTRE_EA_INODE, / Lustre-style ea_inode /
1944	EXT4_STATE_VERITY_IN_PROGRESS, / building fs-verity Merkle tree /
1945	EXT4_STATE_FC_COMMITTING, / Fast commit ongoing /
1946	EXT4_STATE_FC_FLUSHING_DATA, / Fast commit flushing data /
1947	EXT4_STATE_ORPHAN_FILE, / Inode orphaned in orphan file /
1948	};
1949
1950	#define EXT4_INODE_BIT_FNS(name, field, offset) \
1951	static inline int ext4_test_inode_##name(struct inode *inode, int bit) \
1952	{ \
1953	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1954	} \
1955	static inline void ext4_set_inode_##name(struct inode *inode, int bit) \
1956	{ \
1957	set_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1958	} \
1959	static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1960	{ \
1961	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
1962	}
1963
1964	/ Add these declarations here only so that these functions can be*
1965	* found by name. Otherwise, they are very hard to locate. */
1966	static inline int ext4_test_inode_flag(struct inode inode, int* bit);
1967	static inline void ext4_set_inode_flag(struct inode inode, int* bit);
1968	static inline void ext4_clear_inode_flag(struct inode inode, int* bit);
1969	EXT4_INODE_BIT_FNS(flag, flags, `0`)
1970
1971	/ Add these declarations here only so that these functions can be*
1972	* found by name. Otherwise, they are very hard to locate. */
1973	static inline int ext4_test_inode_state(struct inode inode, int* bit);
1974	static inline void ext4_set_inode_state(struct inode inode, int* bit);
1975	static inline void ext4_clear_inode_state(struct inode inode, int* bit);
1976	#if (BITS_PER_LONG < 64)
1977	EXT4_INODE_BIT_FNS(state, state_flags, `0`)
1978
1979	static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1980	{
1981	(ei)->i_state_flags = `0`;
1982	}
1983	#else
1984	EXT4_INODE_BIT_FNS(state, flags, `32`)
1985
1986	static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1987	{
1988	/ We depend on the fact that callers will set i_flags /
1989	}
1990	#endif
1991	#else
1992	/ Assume that user mode programs are passing in an ext4fs superblock, not*
1993	* a kernel struct super_block. This will allow us to call the feature-test
1994	* macros from user land. */
1995	#define EXT4_SB(sb) (sb)
1996	#endif
1997
1998	static inline bool ext4_verity_in_progress(struct inode *inode)
1999	{
2000	return IS_ENABLED(CONFIG_FS_VERITY) &&
2001	ext4_test_inode_state(inode, bit: EXT4_STATE_VERITY_IN_PROGRESS);
2002	}
2003
2004	#define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
2005
2006	/*
2007	* Check whether the inode is tracked as orphan (either in orphan file or
2008	* orphan list).
2009	*/
2010	static inline bool ext4_inode_orphan_tracked(struct inode *inode)
2011	{
2012	return ext4_test_inode_state(inode, bit: EXT4_STATE_ORPHAN_FILE) \|\|
2013	!list_empty(head: &EXT4_I(inode)->i_orphan);
2014	}
2015
2016	/*
2017	* Codes for operating systems
2018	*/
2019	#define EXT4_OS_LINUX 0
2020	#define EXT4_OS_HURD 1
2021	#define EXT4_OS_MASIX 2
2022	#define EXT4_OS_FREEBSD 3
2023	#define EXT4_OS_LITES 4
2024
2025	/*
2026	* Revision levels
2027	*/
2028	#define EXT4_GOOD_OLD_REV 0 /* The good old (original) format */
2029	#define EXT4_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
2030
2031	#define EXT4_MAX_SUPP_REV EXT4_DYNAMIC_REV
2032
2033	#define EXT4_GOOD_OLD_INODE_SIZE 128
2034
2035	#define EXT4_EXTRA_TIMESTAMP_MAX (((s64)1 << 34) - 1 + S32_MIN)
2036	#define EXT4_NON_EXTRA_TIMESTAMP_MAX S32_MAX
2037	#define EXT4_TIMESTAMP_MIN S32_MIN
2038
2039	/*
2040	* Feature set definitions
2041	*/
2042
2043	#define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001
2044	#define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002
2045	#define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004
2046	#define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008
2047	#define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010
2048	#define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020
2049	#define EXT4_FEATURE_COMPAT_SPARSE_SUPER2 0x0200
2050	/*
2051	* The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
2052	* incompatible only if fast commit blocks are present in the FS. Since we
2053	* clear the journal (and thus the fast commit blocks), we don't mark FS as
2054	* incompatible. We also have a JBD2 incompat feature, which gets set when
2055	* there are fast commit blocks present in the journal.
2056	*/
2057	#define EXT4_FEATURE_COMPAT_FAST_COMMIT 0x0400
2058	#define EXT4_FEATURE_COMPAT_STABLE_INODES 0x0800
2059	#define EXT4_FEATURE_COMPAT_ORPHAN_FILE 0x1000 /* Orphan file exists */
2060
2061	#define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
2062	#define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
2063	#define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
2064	#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
2065	#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
2066	#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
2067	#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
2068	#define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
2069	#define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200
2070	/*
2071	* METADATA_CSUM also enables group descriptor checksums (GDT_CSUM). When
2072	* METADATA_CSUM is set, group descriptor checksums use the same algorithm as
2073	* all other data structures' checksums. However, the METADATA_CSUM and
2074	* GDT_CSUM bits are mutually exclusive.
2075	*/
2076	#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
2077	#define EXT4_FEATURE_RO_COMPAT_READONLY 0x1000
2078	#define EXT4_FEATURE_RO_COMPAT_PROJECT 0x2000
2079	#define EXT4_FEATURE_RO_COMPAT_VERITY 0x8000
2080	#define EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT 0x10000 /* Orphan file may be
2081	non-empty */
2082
2083	#define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
2084	#define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
2085	#define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
2086	#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
2087	#define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
2088	#define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
2089	#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
2090	#define EXT4_FEATURE_INCOMPAT_MMP 0x0100
2091	#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
2092	#define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */
2093	#define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */
2094	#define EXT4_FEATURE_INCOMPAT_CSUM_SEED 0x2000
2095	#define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000 /* >2GB or 3-lvl htree */
2096	#define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000 /* data in inode */
2097	#define EXT4_FEATURE_INCOMPAT_ENCRYPT 0x10000
2098	#define EXT4_FEATURE_INCOMPAT_CASEFOLD 0x20000
2099
2100	extern void ext4_update_dynamic_rev(struct super_block *sb);
2101
2102	#define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
2103	static inline bool ext4_has_feature_##name(struct super_block *sb) \
2104	{ \
2105	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2106	cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
2107	} \
2108	static inline void ext4_set_feature_##name(struct super_block *sb) \
2109	{ \
2110	ext4_update_dynamic_rev(sb); \
2111	EXT4_SB(sb)->s_es->s_feature_compat \|= \
2112	cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
2113	} \
2114	static inline void ext4_clear_feature_##name(struct super_block *sb) \
2115	{ \
2116	EXT4_SB(sb)->s_es->s_feature_compat &= \
2117	~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
2118	}
2119
2120	#define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
2121	static inline bool ext4_has_feature_##name(struct super_block *sb) \
2122	{ \
2123	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2124	cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
2125	} \
2126	static inline void ext4_set_feature_##name(struct super_block *sb) \
2127	{ \
2128	ext4_update_dynamic_rev(sb); \
2129	EXT4_SB(sb)->s_es->s_feature_ro_compat \|= \
2130	cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2131	} \
2132	static inline void ext4_clear_feature_##name(struct super_block *sb) \
2133	{ \
2134	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
2135	~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2136	}
2137
2138	#define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
2139	static inline bool ext4_has_feature_##name(struct super_block *sb) \
2140	{ \
2141	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2142	cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
2143	} \
2144	static inline void ext4_set_feature_##name(struct super_block *sb) \
2145	{ \
2146	ext4_update_dynamic_rev(sb); \
2147	EXT4_SB(sb)->s_es->s_feature_incompat \|= \
2148	cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2149	} \
2150	static inline void ext4_clear_feature_##name(struct super_block *sb) \
2151	{ \
2152	EXT4_SB(sb)->s_es->s_feature_incompat &= \
2153	~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2154	}
2155
2156	EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc, DIR_PREALLOC)
2157	EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes, IMAGIC_INODES)
2158	EXT4_FEATURE_COMPAT_FUNCS(journal, HAS_JOURNAL)
2159	EXT4_FEATURE_COMPAT_FUNCS(xattr, EXT_ATTR)
2160	EXT4_FEATURE_COMPAT_FUNCS(resize_inode, RESIZE_INODE)
2161	EXT4_FEATURE_COMPAT_FUNCS(dir_index, DIR_INDEX)
2162	EXT4_FEATURE_COMPAT_FUNCS(sparse_super2, SPARSE_SUPER2)
2163	EXT4_FEATURE_COMPAT_FUNCS(fast_commit, FAST_COMMIT)
2164	EXT4_FEATURE_COMPAT_FUNCS(stable_inodes, STABLE_INODES)
2165	EXT4_FEATURE_COMPAT_FUNCS(orphan_file, ORPHAN_FILE)
2166
2167	EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super, SPARSE_SUPER)
2168	EXT4_FEATURE_RO_COMPAT_FUNCS(large_file, LARGE_FILE)
2169	EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir, BTREE_DIR)
2170	EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file, HUGE_FILE)
2171	EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum, GDT_CSUM)
2172	EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink, DIR_NLINK)
2173	EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize, EXTRA_ISIZE)
2174	EXT4_FEATURE_RO_COMPAT_FUNCS(quota, QUOTA)
2175	EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc, BIGALLOC)
2176	EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum, METADATA_CSUM)
2177	EXT4_FEATURE_RO_COMPAT_FUNCS(readonly, READONLY)
2178	EXT4_FEATURE_RO_COMPAT_FUNCS(project, PROJECT)
2179	EXT4_FEATURE_RO_COMPAT_FUNCS(verity, VERITY)
2180	EXT4_FEATURE_RO_COMPAT_FUNCS(orphan_present, ORPHAN_PRESENT)
2181
2182	EXT4_FEATURE_INCOMPAT_FUNCS(compression, COMPRESSION)
2183	EXT4_FEATURE_INCOMPAT_FUNCS(filetype, FILETYPE)
2184	EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery, RECOVER)
2185	EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev, JOURNAL_DEV)
2186	EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg, META_BG)
2187	EXT4_FEATURE_INCOMPAT_FUNCS(extents, EXTENTS)
2188	EXT4_FEATURE_INCOMPAT_FUNCS(`64bit`, `64BIT`)
2189	EXT4_FEATURE_INCOMPAT_FUNCS(mmp, MMP)
2190	EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg, FLEX_BG)
2191	EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode, EA_INODE)
2192	EXT4_FEATURE_INCOMPAT_FUNCS(dirdata, DIRDATA)
2193	EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed, CSUM_SEED)
2194	EXT4_FEATURE_INCOMPAT_FUNCS(largedir, LARGEDIR)
2195	EXT4_FEATURE_INCOMPAT_FUNCS(inline_data, INLINE_DATA)
2196	EXT4_FEATURE_INCOMPAT_FUNCS(encrypt, ENCRYPT)
2197	EXT4_FEATURE_INCOMPAT_FUNCS(casefold, CASEFOLD)
2198
2199	#define EXT2_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
2200	#define EXT2_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE\| \
2201	EXT4_FEATURE_INCOMPAT_META_BG)
2202	#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER\| \
2203	EXT4_FEATURE_RO_COMPAT_LARGE_FILE\| \
2204	EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2205
2206	#define EXT3_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
2207	#define EXT3_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE\| \
2208	EXT4_FEATURE_INCOMPAT_RECOVER\| \
2209	EXT4_FEATURE_INCOMPAT_META_BG)
2210	#define EXT3_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER\| \
2211	EXT4_FEATURE_RO_COMPAT_LARGE_FILE\| \
2212	EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2213
2214	#define EXT4_FEATURE_COMPAT_SUPP (EXT4_FEATURE_COMPAT_EXT_ATTR\| \
2215	EXT4_FEATURE_COMPAT_ORPHAN_FILE)
2216	#define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE\| \
2217	EXT4_FEATURE_INCOMPAT_RECOVER\| \
2218	EXT4_FEATURE_INCOMPAT_META_BG\| \
2219	EXT4_FEATURE_INCOMPAT_EXTENTS\| \
2220	EXT4_FEATURE_INCOMPAT_64BIT\| \
2221	EXT4_FEATURE_INCOMPAT_FLEX_BG\| \
2222	EXT4_FEATURE_INCOMPAT_EA_INODE\| \
2223	EXT4_FEATURE_INCOMPAT_MMP \| \
2224	EXT4_FEATURE_INCOMPAT_INLINE_DATA \| \
2225	EXT4_FEATURE_INCOMPAT_ENCRYPT \| \
2226	EXT4_FEATURE_INCOMPAT_CASEFOLD \| \
2227	EXT4_FEATURE_INCOMPAT_CSUM_SEED \| \
2228	EXT4_FEATURE_INCOMPAT_LARGEDIR)
2229	#define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER\| \
2230	EXT4_FEATURE_RO_COMPAT_LARGE_FILE\| \
2231	EXT4_FEATURE_RO_COMPAT_GDT_CSUM\| \
2232	EXT4_FEATURE_RO_COMPAT_DIR_NLINK \| \
2233	EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE \| \
2234	EXT4_FEATURE_RO_COMPAT_BTREE_DIR \|\
2235	EXT4_FEATURE_RO_COMPAT_HUGE_FILE \|\
2236	EXT4_FEATURE_RO_COMPAT_BIGALLOC \|\
2237	EXT4_FEATURE_RO_COMPAT_METADATA_CSUM\|\
2238	EXT4_FEATURE_RO_COMPAT_QUOTA \|\
2239	EXT4_FEATURE_RO_COMPAT_PROJECT \|\
2240	EXT4_FEATURE_RO_COMPAT_VERITY \|\
2241	EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT)
2242
2243	#define EXTN_FEATURE_FUNCS(ver) \
2244	static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2245	{ \
2246	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2247	cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2248	} \
2249	static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2250	{ \
2251	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2252	cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2253	} \
2254	static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2255	{ \
2256	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2257	cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2258	}
2259
2260	EXTN_FEATURE_FUNCS(`2`)
2261	EXTN_FEATURE_FUNCS(`3`)
2262	EXTN_FEATURE_FUNCS(`4`)
2263
2264	static inline bool ext4_has_compat_features(struct super_block *sb)
2265	{
2266	return (EXT4_SB(sb)->s_es->s_feature_compat != `0`);
2267	}
2268	static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2269	{
2270	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != `0`);
2271	}
2272	static inline bool ext4_has_incompat_features(struct super_block *sb)
2273	{
2274	return (EXT4_SB(sb)->s_es->s_feature_incompat != `0`);
2275	}
2276
2277	extern int ext4_feature_set_ok(struct super_block sb, int* readonly);
2278
2279	/*
2280	* Superblock flags
2281	*/
2282	enum {
2283	EXT4_FLAGS_RESIZING, / Avoid superblock update and resize race /
2284	EXT4_FLAGS_SHUTDOWN, / Prevent access to the file system /
2285	EXT4_FLAGS_BDEV_IS_DAX, / Current block device support DAX /
2286	EXT4_FLAGS_EMERGENCY_RO,/ Emergency read-only due to fs errors /
2287	};
2288
2289	static inline int ext4_forced_shutdown(struct super_block *sb)
2290	{
2291	return test_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);
2292	}
2293
2294	static inline int ext4_emergency_ro(struct super_block *sb)
2295	{
2296	return test_bit(EXT4_FLAGS_EMERGENCY_RO, &EXT4_SB(sb)->s_ext4_flags);
2297	}
2298
2299	static inline int ext4_emergency_state(struct super_block *sb)
2300	{
2301	if (unlikely(ext4_forced_shutdown(sb)))
2302	return -EIO;
2303	if (unlikely(ext4_emergency_ro(sb)))
2304	return -EROFS;
2305	return `0`;
2306	}
2307
2308	/*
2309	* Default values for user and/or group using reserved blocks
2310	*/
2311	#define EXT4_DEF_RESUID 0
2312	#define EXT4_DEF_RESGID 0
2313
2314	/*
2315	* Default project ID
2316	*/
2317	#define EXT4_DEF_PROJID 0
2318
2319	#define EXT4_DEF_INODE_READAHEAD_BLKS 32
2320
2321	/*
2322	* Default mount options
2323	*/
2324	#define EXT4_DEFM_DEBUG 0x0001
2325	#define EXT4_DEFM_BSDGROUPS 0x0002
2326	#define EXT4_DEFM_XATTR_USER 0x0004
2327	#define EXT4_DEFM_ACL 0x0008
2328	#define EXT4_DEFM_UID16 0x0010
2329	#define EXT4_DEFM_JMODE 0x0060
2330	#define EXT4_DEFM_JMODE_DATA 0x0020
2331	#define EXT4_DEFM_JMODE_ORDERED 0x0040
2332	#define EXT4_DEFM_JMODE_WBACK 0x0060
2333	#define EXT4_DEFM_NOBARRIER 0x0100
2334	#define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2335	#define EXT4_DEFM_DISCARD 0x0400
2336	#define EXT4_DEFM_NODELALLOC 0x0800
2337
2338	/*
2339	* Default journal batch times and ioprio.
2340	*/
2341	#define EXT4_DEF_MIN_BATCH_TIME 0
2342	#define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
2343	#define EXT4_DEF_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
2344
2345
2346	/*
2347	* Default values for superblock update
2348	*/
2349	#define EXT4_DEF_SB_UPDATE_INTERVAL_SEC (3600) /* seconds (1 hour) */
2350	#define EXT4_DEF_SB_UPDATE_INTERVAL_KB (16384) /* kilobytes (16MB) */
2351
2352
2353	/*
2354	* Minimum number of groups in a flexgroup before we separate out
2355	* directories into the first block group of a flexgroup
2356	*/
2357	#define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
2358
2359	/*
2360	* Structure of a directory entry
2361	*/
2362	#define EXT4_NAME_LEN 255
2363	/*
2364	* Base length of the ext4 directory entry excluding the name length
2365	*/
2366	#define EXT4_BASE_DIR_LEN (sizeof(struct ext4_dir_entry_2) - EXT4_NAME_LEN)
2367
2368	struct ext4_dir_entry {
2369	__le32 inode; / Inode number /
2370	__le16 rec_len; / Directory entry length /
2371	__le16 name_len; / Name length /
2372	char name[EXT4_NAME_LEN]; / File name /
2373	};
2374
2375
2376	/*
2377	* Encrypted Casefolded entries require saving the hash on disk. This structure
2378	* followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
2379	* boundary.
2380	*/
2381	struct ext4_dir_entry_hash {
2382	__le32 hash;
2383	__le32 minor_hash;
2384	};
2385
2386	/*
2387	* The new version of the directory entry. Since EXT4 structures are
2388	* stored in intel byte order, and the name_len field could never be
2389	* bigger than 255 chars, it's safe to reclaim the extra byte for the
2390	* file_type field.
2391	*/
2392	struct ext4_dir_entry_2 {
2393	__le32 inode; / Inode number /
2394	__le16 rec_len; / Directory entry length /
2395	__u8 name_len; / Name length /
2396	__u8 file_type; / See file type macros EXT4_FT_* below /
2397	char name[EXT4_NAME_LEN]; / File name /
2398	};
2399
2400	/*
2401	* Access the hashes at the end of ext4_dir_entry_2
2402	*/
2403	#define EXT4_DIRENT_HASHES(entry) \
2404	((struct ext4_dir_entry_hash *) \
2405	(((void *)(entry)) + \
2406	((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
2407	#define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(entry)->hash)
2408	#define EXT4_DIRENT_MINOR_HASH(entry) \
2409	le32_to_cpu(EXT4_DIRENT_HASHES(entry)->minor_hash)
2410
2411	static inline bool ext4_hash_in_dirent(const struct inode *inode)
2412	{
2413	return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
2414	}
2415
2416	/*
2417	* This is a bogus directory entry at the end of each leaf block that
2418	* records checksums.
2419	*/
2420	struct ext4_dir_entry_tail {
2421	__le32 det_reserved_zero1; / Pretend to be unused /
2422	__le16 det_rec_len; / 12 /
2423	__u8 det_reserved_zero2; / Zero name length /
2424	__u8 det_reserved_ft; / 0xDE, fake file type /
2425	__le32 det_checksum; / crc32c(uuid+inum+dirblock) /
2426	};
2427
2428	#define EXT4_DIRENT_TAIL(block, blocksize) \
2429	((struct ext4_dir_entry_tail )(((void )(block)) + \
2430	((blocksize) - \
2431	sizeof(struct ext4_dir_entry_tail))))
2432
2433	/*
2434	* Ext4 directory file types. Only the low 3 bits are used. The
2435	* other bits are reserved for now.
2436	*/
2437	#define EXT4_FT_UNKNOWN 0
2438	#define EXT4_FT_REG_FILE 1
2439	#define EXT4_FT_DIR 2
2440	#define EXT4_FT_CHRDEV 3
2441	#define EXT4_FT_BLKDEV 4
2442	#define EXT4_FT_FIFO 5
2443	#define EXT4_FT_SOCK 6
2444	#define EXT4_FT_SYMLINK 7
2445
2446	#define EXT4_FT_MAX 8
2447
2448	#define EXT4_FT_DIR_CSUM 0xDE
2449
2450	/*
2451	* EXT4_DIR_PAD defines the directory entries boundaries
2452	*
2453	* NOTE: It must be a multiple of 4
2454	*/
2455	#define EXT4_DIR_PAD 4
2456	#define EXT4_DIR_ROUND (EXT4_DIR_PAD - 1)
2457	#define EXT4_MAX_REC_LEN ((1<<16)-1)
2458
2459	/*
2460	* The rec_len is dependent on the type of directory. Directories that are
2461	* casefolded and encrypted need to store the hash as well, so we add room for
2462	* ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
2463	* pass NULL for dir, as those entries do not use the extra fields.
2464	*/
2465	static inline unsigned int ext4_dir_rec_len(__u8 name_len,
2466	const struct inode *dir)
2467	{
2468	int rec_len = (name_len + `8` + EXT4_DIR_ROUND);
2469
2470	if (dir && ext4_hash_in_dirent(inode: dir))
2471	rec_len += sizeof(struct ext4_dir_entry_hash);
2472	return (rec_len & ~EXT4_DIR_ROUND);
2473	}
2474
2475	/*
2476	* If we ever get support for fs block sizes > page_size, we'll need
2477	* to remove the #if statements in the next two functions...
2478	*/
2479	static inline unsigned int
2480	ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2481	{
2482	unsigned len = le16_to_cpu(dlen);
2483
2484	#if (PAGE_SIZE >= 65536)
2485	if (len == EXT4_MAX_REC_LEN \|\| len == `0`)
2486	return blocksize;
2487	return (len & `65532`) \| ((len & `3`) << `16`);
2488	#else
2489	return len;
2490	#endif
2491	}
2492
2493	static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2494	{
2495	BUG_ON((len > blocksize) \|\| (blocksize > (`1` << `18`)) \|\| (len & `3`));
2496	#if (PAGE_SIZE >= 65536)
2497	if (len < `65536`)
2498	return cpu_to_le16(len);
2499	if (len == blocksize) {
2500	if (blocksize == `65536`)
2501	return cpu_to_le16(EXT4_MAX_REC_LEN);
2502	else
2503	return cpu_to_le16(`0`);
2504	}
2505	return cpu_to_le16((len & `65532`) \| ((len >> `16`) & `3`));
2506	#else
2507	return cpu_to_le16(len);
2508	#endif
2509	}
2510
2511	/*
2512	* Hash Tree Directory indexing
2513	* (c) Daniel Phillips, 2001
2514	*/
2515
2516	#define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2517	ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2518	#define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2519	!(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2520	#define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 \|\| (dir)->i_nlink == 1)
2521
2522	/ Legal values for the dx_root hash_version field: /
2523
2524	#define DX_HASH_LEGACY 0
2525	#define DX_HASH_HALF_MD4 1
2526	#define DX_HASH_TEA 2
2527	#define DX_HASH_LEGACY_UNSIGNED 3
2528	#define DX_HASH_HALF_MD4_UNSIGNED 4
2529	#define DX_HASH_TEA_UNSIGNED 5
2530	#define DX_HASH_SIPHASH 6
2531	#define DX_HASH_LAST DX_HASH_SIPHASH
2532
2533	static inline u32 ext4_chksum(u32 crc, const void address, unsigned* int length)
2534	{
2535	return crc32c(crc, p: address, len: length);
2536	}
2537
2538	#ifdef __KERNEL__
2539
2540	/ hash info structure used by the directory hash /
2541	struct dx_hash_info
2542	{
2543	u32 hash;
2544	u32 minor_hash;
2545	int hash_version;
2546	u32 *seed;
2547	};
2548
2549
2550	/ 32 and 64 bit signed EOF for dx directories /
2551	#define EXT4_HTREE_EOF_32BIT ((1UL << (32 - 1)) - 1)
2552	#define EXT4_HTREE_EOF_64BIT ((1ULL << (64 - 1)) - 1)
2553
2554
2555	/*
2556	* Control parameters used by ext4_htree_next_block
2557	*/
2558	#define HASH_NB_ALWAYS 1
2559
2560	struct ext4_filename {
2561	const struct qstr *usr_fname;
2562	struct fscrypt_str disk_name;
2563	struct dx_hash_info hinfo;
2564	#ifdef CONFIG_FS_ENCRYPTION
2565	struct fscrypt_str crypto_buf;
2566	#endif
2567	#if IS_ENABLED(CONFIG_UNICODE)
2568	struct qstr cf_name;
2569	#endif
2570	};
2571
2572	#define fname_name(p) ((p)->disk_name.name)
2573	#define fname_usr_name(p) ((p)->usr_fname->name)
2574	#define fname_len(p) ((p)->disk_name.len)
2575
2576	/*
2577	* Describe an inode's exact location on disk and in memory
2578	*/
2579	struct ext4_iloc
2580	{
2581	struct buffer_head *bh;
2582	unsigned long offset;
2583	ext4_group_t block_group;
2584	};
2585
2586	static inline struct ext4_inode ext4_raw_inode(struct* ext4_iloc *iloc)
2587	{
2588	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2589	}
2590
2591	static inline bool ext4_is_quota_file(struct inode *inode)
2592	{
2593	return IS_NOQUOTA(inode) &&
2594	!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2595	}
2596
2597	/*
2598	* This structure is stuffed into the struct file's private_data field
2599	* for directories. It is where we put information so that we can do
2600	* readdir operations in hash tree order.
2601	*/
2602	struct dir_private_info {
2603	struct rb_root root;
2604	struct rb_node *curr_node;
2605	struct fname *extra_fname;
2606	loff_t last_pos;
2607	__u32 curr_hash;
2608	__u32 curr_minor_hash;
2609	__u32 next_hash;
2610	u64 cookie;
2611	bool initialized;
2612	};
2613
2614	/ calculate the first block number of the group /
2615	static inline ext4_fsblk_t
2616	ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2617	{
2618	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2619	le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2620	}
2621
2622	/*
2623	* Special error return code only used by dx_probe() and its callers.
2624	*/
2625	#define ERR_BAD_DX_DIR (-(MAX_ERRNO - 1))
2626
2627	/ htree levels for ext4 /
2628	#define EXT4_HTREE_LEVEL_COMPAT 2
2629	#define EXT4_HTREE_LEVEL 3
2630
2631	static inline int ext4_dir_htree_level(struct super_block *sb)
2632	{
2633	return ext4_has_feature_largedir(sb) ?
2634	EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2635	}
2636
2637	/*
2638	* Timeout and state flag for lazy initialization inode thread.
2639	*/
2640	#define EXT4_DEF_LI_WAIT_MULT 10
2641	#define EXT4_DEF_LI_MAX_START_DELAY 5
2642	#define EXT4_LAZYINIT_QUIT 0x0001
2643	#define EXT4_LAZYINIT_RUNNING 0x0002
2644
2645	/*
2646	* Lazy inode table initialization info
2647	*/
2648	struct ext4_lazy_init {
2649	unsigned long li_state;
2650	struct list_head li_request_list;
2651	struct mutex li_list_mtx;
2652	};
2653
2654	enum ext4_li_mode {
2655	EXT4_LI_MODE_PREFETCH_BBITMAP,
2656	EXT4_LI_MODE_ITABLE,
2657	};
2658
2659	struct ext4_li_request {
2660	struct super_block *lr_super;
2661	enum ext4_li_mode lr_mode;
2662	ext4_group_t lr_first_not_zeroed;
2663	ext4_group_t lr_next_group;
2664	struct list_head lr_request;
2665	unsigned long lr_next_sched;
2666	unsigned long lr_timeout;
2667	};
2668
2669	struct ext4_features {
2670	struct kobject f_kobj;
2671	struct completion f_kobj_unregister;
2672	};
2673
2674	/*
2675	* This structure will be used for multiple mount protection. It will be
2676	* written into the block number saved in the s_mmp_block field in the
2677	* superblock. Programs that check MMP should assume that if
2678	* SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2679	* to use the filesystem, regardless of how old the timestamp is.
2680	*/
2681	#define EXT4_MMP_MAGIC 0x004D4D50U /* ASCII for MMP */
2682	#define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2683	#define EXT4_MMP_SEQ_FSCK 0xE24D4D50U /* mmp_seq value when being fscked */
2684	#define EXT4_MMP_SEQ_MAX 0xE24D4D4FU /* maximum valid mmp_seq value */
2685
2686	struct mmp_struct {
2687	__le32 mmp_magic; / Magic number for MMP /
2688	__le32 mmp_seq; / Sequence no. updated periodically /
2689
2690	/*
2691	* mmp_time, mmp_nodename & mmp_bdevname are only used for information
2692	* purposes and do not affect the correctness of the algorithm
2693	*/
2694	__le64 mmp_time; / Time last updated /
2695	char mmp_nodename[`64`]; / Node which last updated MMP block /
2696	char mmp_bdevname[`32`]; / Bdev which last updated MMP block /
2697
2698	/*
2699	* mmp_check_interval is used to verify if the MMP block has been
2700	* updated on the block device. The value is updated based on the
2701	* maximum time to write the MMP block during an update cycle.
2702	*/
2703	__le16 mmp_check_interval;
2704
2705	__le16 mmp_pad1;
2706	__le32 mmp_pad2[`226`];
2707	__le32 mmp_checksum; / crc32c(uuid+mmp_block) /
2708	};
2709
2710	/ arguments passed to the mmp thread /
2711	struct mmpd_data {
2712	struct buffer_head bh; /* bh from initial read_mmp_block() /
2713	struct super_block sb; /* super block of the fs /
2714	};
2715
2716	/*
2717	* Check interval multiplier
2718	* The MMP block is written every update interval and initially checked every
2719	* update interval x the multiplier (the value is then adapted based on the
2720	* write latency). The reason is that writes can be delayed under load and we
2721	* don't want readers to incorrectly assume that the filesystem is no longer
2722	* in use.
2723	*/
2724	#define EXT4_MMP_CHECK_MULT 2UL
2725
2726	/*
2727	* Minimum interval for MMP checking in seconds.
2728	*/
2729	#define EXT4_MMP_MIN_CHECK_INTERVAL 5UL
2730
2731	/*
2732	* Maximum interval for MMP checking in seconds.
2733	*/
2734	#define EXT4_MMP_MAX_CHECK_INTERVAL 300UL
2735
2736	/*
2737	* Function prototypes
2738	*/
2739
2740	/*
2741	* Ok, these declarations are also in <linux/kernel.h> but none of the
2742	* ext4 source programs needs to include it so they are duplicated here.
2743	*/
2744	# define NORET_TYPE /**/
2745	# define ATTRIB_NORET __attribute__((noreturn))
2746	# define NORET_AND noreturn,
2747
2748	/ bitmap.c /
2749	extern unsigned int ext4_count_free(char bitmap, unsigned* numchars);
2750	void ext4_inode_bitmap_csum_set(struct super_block *sb,
2751	struct ext4_group_desc *gdp,
2752	struct buffer_head *bh);
2753	int ext4_inode_bitmap_csum_verify(struct super_block *sb,
2754	struct ext4_group_desc *gdp,
2755	struct buffer_head *bh);
2756	void ext4_block_bitmap_csum_set(struct super_block *sb,
2757	struct ext4_group_desc *gdp,
2758	struct buffer_head *bh);
2759	int ext4_block_bitmap_csum_verify(struct super_block *sb,
2760	struct ext4_group_desc *gdp,
2761	struct buffer_head *bh);
2762
2763	/ balloc.c /
2764	extern void ext4_get_group_no_and_offset(struct super_block *sb,
2765	ext4_fsblk_t blocknr,
2766	ext4_group_t *blockgrpp,
2767	ext4_grpblk_t *offsetp);
2768	extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2769	ext4_fsblk_t block);
2770
2771	extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2772	extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2773	ext4_group_t group);
2774	extern ext4_fsblk_t ext4_new_meta_blocks(handle_t handle, struct* inode *inode,
2775	ext4_fsblk_t goal,
2776	unsigned int flags,
2777	unsigned long *count,
2778	int *errp);
2779	extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2780	s64 nclusters, unsigned int flags);
2781	extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2782	extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2783	ext4_group_t block_group,
2784	struct buffer_head ** bh);
2785	extern struct ext4_group_info ext4_get_group_info(struct* super_block *sb,
2786	ext4_group_t group);
2787	extern int ext4_should_retry_alloc(struct super_block sb, int* *retries);
2788
2789	extern struct buffer_head ext4_read_block_bitmap_nowait(struct* super_block *sb,
2790	ext4_group_t block_group,
2791	bool ignore_locked);
2792	extern int ext4_wait_block_bitmap(struct super_block *sb,
2793	ext4_group_t block_group,
2794	struct buffer_head *bh);
2795	extern struct buffer_head ext4_read_block_bitmap(struct* super_block *sb,
2796	ext4_group_t block_group);
2797	extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2798	ext4_group_t block_group,
2799	struct ext4_group_desc *gdp);
2800	ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2801
2802	#if IS_ENABLED(CONFIG_UNICODE)
2803	extern int ext4_fname_setup_ci_filename(struct inode *dir,
2804	const struct qstr *iname,
2805	struct ext4_filename *fname);
2806
2807	static inline void ext4_fname_free_ci_filename(struct ext4_filename *fname)
2808	{
2809	kfree(fname->cf_name.name);
2810	fname->cf_name.name = NULL;
2811	}
2812	#else
2813	static inline int ext4_fname_setup_ci_filename(struct inode *dir,
2814	const struct qstr *iname,
2815	struct ext4_filename *fname)
2816	{
2817	return `0`;
2818	}
2819
2820	static inline void ext4_fname_free_ci_filename(struct ext4_filename *fname)
2821	{
2822	}
2823	#endif
2824
2825	/ ext4 encryption related stuff goes here crypto.c /
2826	#ifdef CONFIG_FS_ENCRYPTION
2827	extern const struct fscrypt_operations ext4_cryptops;
2828
2829	int ext4_fname_setup_filename(struct inode dir, const* struct qstr *iname,
2830	int lookup, struct ext4_filename *fname);
2831
2832	int ext4_fname_prepare_lookup(struct inode dir, struct* dentry *dentry,
2833	struct ext4_filename *fname);
2834
2835	void ext4_fname_free_filename(struct ext4_filename *fname);
2836
2837	int ext4_ioctl_get_encryption_pwsalt(struct file filp, void* __user *arg);
2838
2839	#else /* !CONFIG_FS_ENCRYPTION */
2840	static inline int ext4_fname_setup_filename(struct inode *dir,
2841	const struct qstr *iname,
2842	int lookup,
2843	struct ext4_filename *fname)
2844	{
2845	fname->usr_fname = iname;
2846	fname->disk_name.name = (unsigned char *) iname->name;
2847	fname->disk_name.len = iname->len;
2848
2849	return ext4_fname_setup_ci_filename(dir, iname, fname);
2850	}
2851
2852	static inline int ext4_fname_prepare_lookup(struct inode *dir,
2853	struct dentry *dentry,
2854	struct ext4_filename *fname)
2855	{
2856	return ext4_fname_setup_filename(dir, iname: &dentry->d_name, lookup: `1`, fname);
2857	}
2858
2859	static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2860	{
2861	ext4_fname_free_ci_filename(fname);
2862	}
2863
2864	static inline int ext4_ioctl_get_encryption_pwsalt(struct file *filp,
2865	void __user *arg)
2866	{
2867	return -EOPNOTSUPP;
2868	}
2869	#endif /* !CONFIG_FS_ENCRYPTION */
2870
2871	/ dir.c /
2872	extern int __ext4_check_dir_entry(const char , unsigned* int, struct inode *,
2873	struct file *,
2874	struct ext4_dir_entry_2 *,
2875	struct buffer_head , char* , int*,
2876	unsigned int);
2877	#define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
2878	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2879	(de), (bh), (buf), (size), (offset)))
2880	extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2881	__u32 minor_hash,
2882	struct ext4_dir_entry_2 *dirent,
2883	struct fscrypt_str *ent_name);
2884	extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2885	extern int ext4_find_dest_de(struct inode dir, struct* buffer_head *bh,
2886	void buf, int* buf_size,
2887	struct ext4_filename *fname,
2888	struct ext4_dir_entry_2 **dest_de);
2889	void ext4_insert_dentry(struct inode dir, struct* inode *inode,
2890	struct ext4_dir_entry_2 *de,
2891	int buf_size,
2892	struct ext4_filename *fname);
2893	static inline void ext4_update_dx_flag(struct inode *inode)
2894	{
2895	if (!ext4_has_feature_dir_index(sb: inode->i_sb) &&
2896	ext4_test_inode_flag(inode, bit: EXT4_INODE_INDEX)) {
2897	/ ext4_iget() should have caught this... /
2898	WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2899	ext4_clear_inode_flag(inode, bit: EXT4_INODE_INDEX);
2900	}
2901	}
2902	static const unsigned char ext4_filetype_table[] = {
2903	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2904	};
2905
2906	static inline unsigned char get_dtype(struct super_block sb, int* filetype)
2907	{
2908	if (!ext4_has_feature_filetype(sb) \|\| filetype >= EXT4_FT_MAX)
2909	return DT_UNKNOWN;
2910
2911	return ext4_filetype_table[filetype];
2912	}
2913	extern int ext4_check_all_de(struct inode dir, struct* buffer_head *bh,
2914	void buf, int* buf_size);
2915
2916	/ fsync.c /
2917	extern int ext4_sync_file(struct file , loff_t, loff_t, int*);
2918
2919	/ hash.c /
2920	extern int ext4fs_dirhash(const struct inode dir, const* char name, int* len,
2921	struct dx_hash_info *hinfo);
2922
2923	/ ialloc.c /
2924	extern int ext4_mark_inode_used(struct super_block sb, int* ino);
2925	extern struct inode __ext4_new_inode(struct* mnt_idmap , handle_t ,
2926	struct inode *, umode_t,
2927	const struct qstr *qstr, __u32 goal,
2928	uid_t *owner, __u32 i_flags,
2929	int handle_type, unsigned int line_no,
2930	int nblocks);
2931
2932	#define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2933	__ext4_new_inode(&nop_mnt_idmap, (handle), (dir), (mode), (qstr), \
2934	(goal), (owner), i_flags, 0, 0, 0)
2935	#define ext4_new_inode_start_handle(idmap, dir, mode, qstr, goal, owner, \
2936	type, nblocks) \
2937	__ext4_new_inode((idmap), NULL, (dir), (mode), (qstr), (goal), (owner), \
2938	0, (type), __LINE__, (nblocks))
2939
2940
2941	extern void ext4_free_inode(handle_t , struct* inode *);
2942	extern struct inode * ext4_orphan_get(struct super_block , unsigned* long);
2943	extern unsigned long ext4_count_free_inodes(struct super_block *);
2944	extern unsigned long ext4_count_dirs(struct super_block *);
2945	extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2946	extern int ext4_init_inode_table(struct super_block *sb,
2947	ext4_group_t group, int barrier);
2948	extern void ext4_end_bitmap_read(struct buffer_head bh, int* uptodate);
2949
2950	/ fast_commit.c /
2951	int ext4_fc_info_show(struct seq_file seq, void* *v);
2952	void ext4_fc_init(struct super_block sb, journal_t journal);
2953	void ext4_fc_init_inode(struct inode *inode);
2954	void ext4_fc_track_range(handle_t handle, struct* inode *inode, ext4_lblk_t start,
2955	ext4_lblk_t end);
2956	void __ext4_fc_track_unlink(handle_t handle, struct* inode *inode,
2957	struct dentry *dentry);
2958	void __ext4_fc_track_link(handle_t handle, struct* inode *inode,
2959	struct dentry *dentry);
2960	void ext4_fc_track_unlink(handle_t handle, struct* dentry *dentry);
2961	void ext4_fc_track_link(handle_t handle, struct* dentry *dentry);
2962	void __ext4_fc_track_create(handle_t handle, struct* inode *inode,
2963	struct dentry *dentry);
2964	void ext4_fc_track_create(handle_t handle, struct* dentry *dentry);
2965	void ext4_fc_track_inode(handle_t handle, struct* inode *inode);
2966	void ext4_fc_mark_ineligible(struct super_block sb, int* reason, handle_t *handle);
2967	void ext4_fc_del(struct inode *inode);
2968	bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2969	void ext4_fc_replay_cleanup(struct super_block *sb);
2970	int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2971	int __init ext4_fc_init_dentry_cache(void);
2972	void ext4_fc_destroy_dentry_cache(void);
2973	int ext4_fc_record_regions(struct super_block sb, int* ino,
2974	ext4_lblk_t lblk, ext4_fsblk_t pblk,
2975	int len, int replay);
2976
2977	/ mballoc.c /
2978	extern const struct seq_operations ext4_mb_seq_groups_ops;
2979	extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
2980	extern int ext4_seq_mb_stats_show(struct seq_file seq, void* *offset);
2981	extern int ext4_mb_init(struct super_block *);
2982	extern void ext4_mb_release(struct super_block *);
2983	extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2984	struct ext4_allocation_request , int* *);
2985	extern void ext4_discard_preallocations(struct inode *);
2986	extern int __init ext4_init_mballoc(void);
2987	extern void ext4_exit_mballoc(void);
2988	extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2989	ext4_group_t group,
2990	unsigned int nr, int *cnt);
2991	extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2992	unsigned int nr);
2993
2994	extern void ext4_free_blocks(handle_t handle, struct* inode *inode,
2995	struct buffer_head *bh, ext4_fsblk_t block,
2996	unsigned long count, int flags);
2997	extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2998	ext4_group_t ngroups);
2999	extern int ext4_mb_add_groupinfo(struct super_block *sb,
3000	ext4_group_t i, struct ext4_group_desc *desc);
3001	extern int ext4_group_add_blocks(handle_t handle, struct* super_block *sb,
3002	ext4_fsblk_t block, unsigned long count);
3003	extern int ext4_trim_fs(struct super_block , struct* fstrim_range *);
3004	extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
3005	extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
3006	int len, bool state);
3007	static inline bool ext4_mb_cr_expensive(enum criteria cr)
3008	{
3009	return cr >= CR_GOAL_LEN_SLOW;
3010	}
3011
3012	/ inode.c /
3013	void ext4_inode_csum_set(struct inode inode, struct* ext4_inode *raw,
3014	struct ext4_inode_info *ei);
3015	int ext4_inode_is_fast_symlink(struct inode *inode);
3016	void ext4_check_map_extents_env(struct inode *inode);
3017	struct buffer_head ext4_getblk(handle_t , struct inode , ext4_lblk_t, int*);
3018	struct buffer_head ext4_bread(handle_t , struct inode , ext4_lblk_t, int*);
3019	int ext4_bread_batch(struct inode inode, ext4_lblk_t block, int* bh_count,
3020	bool wait, struct buffer_head **bhs);
3021	int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
3022	struct buffer_head bh_result, int* create);
3023	int ext4_get_block(struct inode *inode, sector_t iblock,
3024	struct buffer_head bh_result, int* create);
3025	int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
3026	struct buffer_head bh, int* create);
3027	int ext4_walk_page_buffers(handle_t *handle,
3028	struct inode *inode,
3029	struct buffer_head *head,
3030	unsigned from,
3031	unsigned to,
3032	int *partial,
3033	int (fn)(handle_t handle, struct inode *inode,
3034	struct buffer_head *bh));
3035	int do_journal_get_write_access(handle_t handle, struct* inode *inode,
3036	struct buffer_head *bh);
3037	void ext4_set_inode_mapping_order(struct inode *inode);
3038	#define FALL_BACK_TO_NONDELALLOC 1
3039	#define CONVERT_INLINE_DATA 2
3040
3041	typedef enum {
3042	EXT4_IGET_NORMAL = `0`,
3043	EXT4_IGET_SPECIAL = `0x0001`, / OK to iget a system inode /
3044	EXT4_IGET_HANDLE = `0x0002`, / Inode # is from a handle /
3045	EXT4_IGET_BAD = `0x0004`, / Allow to iget a bad inode /
3046	EXT4_IGET_EA_INODE = `0x0008` / Inode should contain an EA value /
3047	} ext4_iget_flags;
3048
3049	extern struct inode __ext4_iget(struct* super_block sb, unsigned* long ino,
3050	ext4_iget_flags flags, const char *function,
3051	unsigned int line);
3052
3053	#define ext4_iget(sb, ino, flags) \
3054	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
3055
3056	extern int ext4_write_inode(struct inode , struct* writeback_control *);
3057	extern int ext4_setattr(struct mnt_idmap , struct* dentry *,
3058	struct iattr *);
3059	extern u32 ext4_dio_alignment(struct inode *inode);
3060	extern int ext4_getattr(struct mnt_idmap , const* struct path *,
3061	struct kstat , u32, unsigned* int);
3062	extern void ext4_evict_inode(struct inode *);
3063	extern void ext4_clear_inode(struct inode *);
3064	extern int ext4_file_getattr(struct mnt_idmap , const* struct path *,
3065	struct kstat , u32, unsigned* int);
3066	extern void ext4_dirty_inode(struct inode , int*);
3067	extern int ext4_change_inode_journal_flag(struct inode , int*);
3068	extern int ext4_get_inode_loc(struct inode , struct* ext4_iloc *);
3069	extern int ext4_get_fc_inode_loc(struct super_block sb, unsigned* long ino,
3070	struct ext4_iloc *iloc);
3071	extern int ext4_inode_attach_jinode(struct inode *inode);
3072	extern int ext4_can_truncate(struct inode *inode);
3073	extern int ext4_truncate(struct inode *);
3074	extern int ext4_break_layouts(struct inode *);
3075	extern int ext4_truncate_page_cache_block_range(struct inode *inode,
3076	loff_t start, loff_t end);
3077	extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
3078	extern void ext4_set_inode_flags(struct inode *, bool init);
3079	extern int ext4_alloc_da_blocks(struct inode *inode);
3080	extern void ext4_set_aops(struct inode *inode);
3081	extern int ext4_normal_submit_inode_data_buffers(struct jbd2_inode *jinode);
3082	extern int ext4_chunk_trans_blocks(struct inode , int* nrblocks);
3083	extern int ext4_chunk_trans_extent(struct inode inode, int* nrblocks);
3084	extern int ext4_meta_trans_blocks(struct inode inode, int* lblocks,
3085	int pextents);
3086	extern int ext4_zero_partial_blocks(handle_t handle, struct* inode *inode,
3087	loff_t lstart, loff_t lend);
3088	extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
3089	extern qsize_t ext4_get_reserved_space(struct* inode *inode);
3090	extern int ext4_get_projid(struct inode inode, kprojid_t projid);
3091	extern void ext4_da_release_space(struct inode inode, int* to_free);
3092	extern void ext4_da_update_reserve_space(struct inode *inode,
3093	int used, int quota_claim);
3094	extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
3095	ext4_fsblk_t pblk, ext4_lblk_t len);
3096
3097	static inline bool is_special_ino(struct super_block sb, unsigned* long ino)
3098	{
3099	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3100
3101	return (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO) \|\|
3102	ino == le32_to_cpu(es->s_usr_quota_inum) \|\|
3103	ino == le32_to_cpu(es->s_grp_quota_inum) \|\|
3104	ino == le32_to_cpu(es->s_prj_quota_inum) \|\|
3105	ino == le32_to_cpu(es->s_orphan_file_inum);
3106	}
3107
3108	/ indirect.c /
3109	extern int ext4_ind_map_blocks(handle_t handle, struct* inode *inode,
3110	struct ext4_map_blocks map, int* flags);
3111	extern int ext4_ind_trans_blocks(struct inode inode, int* nrblocks);
3112	extern void ext4_ind_truncate(handle_t , struct* inode *inode);
3113	extern int ext4_ind_remove_space(handle_t handle, struct* inode *inode,
3114	ext4_lblk_t start, ext4_lblk_t end);
3115
3116	/ ioctl.c /
3117	extern long ext4_ioctl(struct file , unsigned* int, unsigned long);
3118	extern long ext4_compat_ioctl(struct file , unsigned* int, unsigned long);
3119	int ext4_fileattr_set(struct mnt_idmap *idmap,
3120	struct dentry dentry, struct* file_kattr *fa);
3121	int ext4_fileattr_get(struct dentry dentry, struct* file_kattr *fa);
3122	extern void ext4_reset_inode_seed(struct inode *inode);
3123	int ext4_update_overhead(struct super_block *sb, bool force);
3124	int ext4_force_shutdown(struct super_block *sb, u32 flags);
3125
3126	/ migrate.c /
3127	extern int ext4_ext_migrate(struct inode *);
3128	extern int ext4_ind_migrate(struct inode *inode);
3129
3130	/ namei.c /
3131	extern int ext4_init_new_dir(handle_t handle, struct* inode *dir,
3132	struct inode *inode);
3133	extern int ext4_dirblock_csum_verify(struct inode *inode,
3134	struct buffer_head *bh);
3135	extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
3136	__u32 start_minor_hash, __u32 *next_hash);
3137	extern int ext4_search_dir(struct buffer_head *bh,
3138	char *search_buf,
3139	int buf_size,
3140	struct inode *dir,
3141	struct ext4_filename *fname,
3142	unsigned int offset,
3143	struct ext4_dir_entry_2 **res_dir);
3144	extern int ext4_generic_delete_entry(struct inode *dir,
3145	struct ext4_dir_entry_2 *de_del,
3146	struct buffer_head *bh,
3147	void *entry_buf,
3148	int buf_size,
3149	int csum_size);
3150	extern bool ext4_empty_dir(struct inode *inode);
3151
3152	/ resize.c /
3153	extern void ext4_kvfree_array_rcu(void *to_free);
3154	extern int ext4_group_add(struct super_block *sb,
3155	struct ext4_new_group_data *input);
3156	extern int ext4_group_extend(struct super_block *sb,
3157	struct ext4_super_block *es,
3158	ext4_fsblk_t n_blocks_count);
3159	extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
3160	extern unsigned int ext4_list_backups(struct super_block *sb,
3161	unsigned int three, unsigned* int *five,
3162	unsigned int *seven);
3163
3164	/ super.c /
3165	extern struct buffer_head ext4_sb_bread(struct* super_block *sb,
3166	sector_t block, blk_opf_t op_flags);
3167	extern struct buffer_head ext4_sb_bread_unmovable(struct* super_block *sb,
3168	sector_t block);
3169	extern struct buffer_head ext4_sb_bread_nofail(struct* super_block *sb,
3170	sector_t block);
3171	extern void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
3172	bh_end_io_t *end_io, bool simu_fail);
3173	extern int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
3174	bh_end_io_t *end_io, bool simu_fail);
3175	extern int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait);
3176	extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
3177	extern int ext4_seq_options_show(struct seq_file seq, void* *offset);
3178	extern int ext4_calculate_overhead(struct super_block *sb);
3179	extern __le32 ext4_superblock_csum(struct ext4_super_block *es);
3180	extern void ext4_superblock_csum_set(struct super_block *sb);
3181	extern int ext4_alloc_flex_bg_array(struct super_block *sb,
3182	ext4_group_t ngroup);
3183	extern const char ext4_decode_error(struct* super_block sb, int* errno,
3184	char nbuf[`16`]);
3185	extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
3186	ext4_group_t block_group,
3187	unsigned int flags);
3188	extern unsigned int ext4_num_base_meta_blocks(struct super_block *sb,
3189	ext4_group_t block_group);
3190
3191	extern __printf(`7`, `8`)
3192	void __ext4_error(struct super_block , const* char , unsigned* int, bool,
3193	int, __u64, const char *, ...);
3194	extern __printf(`6`, `7`)
3195	void __ext4_error_inode(struct inode , const* char , unsigned* int,
3196	ext4_fsblk_t, int, const char *, ...);
3197	extern __printf(`5`, `6`)
3198	void __ext4_error_file(struct file , const* char , unsigned* int, ext4_fsblk_t,
3199	const char *, ...);
3200	extern void __ext4_std_error(struct super_block , const* char *,
3201	unsigned int, int);
3202	extern __printf(`4`, `5`)
3203	void __ext4_warning(struct super_block , const* char , unsigned* int,
3204	const char *, ...);
3205	extern __printf(`4`, `5`)
3206	void __ext4_warning_inode(const struct inode inode, const* char *function,
3207	unsigned int line, const char *fmt, ...);
3208	extern __printf(`3`, `4`)
3209	void __ext4_msg(struct super_block , const* char , const* char *, ...);
3210	extern void __dump_mmp_msg(struct super_block , struct* mmp_struct *mmp,
3211	const char , unsigned* int, const char *);
3212	extern __printf(`7`, `8`)
3213	void __ext4_grp_locked_error(const char , unsigned* int,
3214	struct super_block *, ext4_group_t,
3215	unsigned long, ext4_fsblk_t,
3216	const char *, ...);
3217
3218	#define EXT4_ERROR_INODE(inode, fmt, a...) \
3219	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3220
3221	#define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...) \
3222	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3223
3224	#define ext4_error_inode_block(inode, block, err, fmt, a...) \
3225	__ext4_error_inode((inode), __func__, __LINE__, (block), (err), \
3226	(fmt), ## a)
3227
3228	#define EXT4_ERROR_FILE(file, block, fmt, a...) \
3229	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3230
3231	#define ext4_abort(sb, err, fmt, a...) \
3232	__ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3233
3234	#ifdef CONFIG_PRINTK
3235
3236	#define ext4_error_inode(inode, func, line, block, fmt, ...) \
3237	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3238	#define ext4_error_inode_err(inode, func, line, block, err, fmt, ...) \
3239	__ext4_error_inode((inode), (func), (line), (block), \
3240	(err), (fmt), ##__VA_ARGS__)
3241	#define ext4_error_file(file, func, line, block, fmt, ...) \
3242	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3243	#define ext4_error(sb, fmt, ...) \
3244	__ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt), \
3245	##__VA_ARGS__)
3246	#define ext4_error_err(sb, err, fmt, ...) \
3247	__ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt), \
3248	##__VA_ARGS__)
3249	#define ext4_warning(sb, fmt, ...) \
3250	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3251	#define ext4_warning_inode(inode, fmt, ...) \
3252	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3253	#define ext4_msg(sb, level, fmt, ...) \
3254	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3255	#define dump_mmp_msg(sb, mmp, msg) \
3256	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3257	#define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...) \
3258	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3259	fmt, ##__VA_ARGS__)
3260
3261	#else
3262
3263	#define ext4_error_inode(inode, func, line, block, fmt, ...) \
3264	do { \
3265	no_printk(fmt, ##__VA_ARGS__); \
3266	__ext4_error_inode(inode, "", 0, block, 0, " "); \
3267	} while (0)
3268	#define ext4_error_inode_err(inode, func, line, block, err, fmt, ...) \
3269	do { \
3270	no_printk(fmt, ##__VA_ARGS__); \
3271	__ext4_error_inode(inode, "", 0, block, err, " "); \
3272	} while (0)
3273	#define ext4_error_file(file, func, line, block, fmt, ...) \
3274	do { \
3275	no_printk(fmt, ##__VA_ARGS__); \
3276	__ext4_error_file(file, "", 0, block, " "); \
3277	} while (0)
3278	#define ext4_error(sb, fmt, ...) \
3279	do { \
3280	no_printk(fmt, ##__VA_ARGS__); \
3281	__ext4_error(sb, "", 0, false, 0, 0, " "); \
3282	} while (0)
3283	#define ext4_error_err(sb, err, fmt, ...) \
3284	do { \
3285	no_printk(fmt, ##__VA_ARGS__); \
3286	__ext4_error(sb, "", 0, false, err, 0, " "); \
3287	} while (0)
3288	#define ext4_warning(sb, fmt, ...) \
3289	do { \
3290	no_printk(fmt, ##__VA_ARGS__); \
3291	__ext4_warning(sb, "", 0, " "); \
3292	} while (0)
3293	#define ext4_warning_inode(inode, fmt, ...) \
3294	do { \
3295	no_printk(fmt, ##__VA_ARGS__); \
3296	__ext4_warning_inode(inode, "", 0, " "); \
3297	} while (0)
3298	#define ext4_msg(sb, level, fmt, ...) \
3299	do { \
3300	no_printk(fmt, ##__VA_ARGS__); \
3301	__ext4_msg(sb, "", " "); \
3302	} while (0)
3303	#define dump_mmp_msg(sb, mmp, msg) \
3304	__dump_mmp_msg(sb, mmp, "", 0, "")
3305	#define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...) \
3306	do { \
3307	no_printk(fmt, ##__VA_ARGS__); \
3308	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " "); \
3309	} while (0)
3310
3311	#endif
3312
3313	extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3314	struct ext4_group_desc *bg);
3315	extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3316	struct ext4_group_desc *bg);
3317	extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3318	struct ext4_group_desc *bg);
3319	extern __u32 ext4_free_group_clusters(struct super_block *sb,
3320	struct ext4_group_desc *bg);
3321	extern __u32 ext4_free_inodes_count(struct super_block *sb,
3322	struct ext4_group_desc *bg);
3323	extern __u32 ext4_used_dirs_count(struct super_block *sb,
3324	struct ext4_group_desc *bg);
3325	extern __u32 ext4_itable_unused_count(struct super_block *sb,
3326	struct ext4_group_desc *bg);
3327	extern void ext4_block_bitmap_set(struct super_block *sb,
3328	struct ext4_group_desc *bg, ext4_fsblk_t blk);
3329	extern void ext4_inode_bitmap_set(struct super_block *sb,
3330	struct ext4_group_desc *bg, ext4_fsblk_t blk);
3331	extern void ext4_inode_table_set(struct super_block *sb,
3332	struct ext4_group_desc *bg, ext4_fsblk_t blk);
3333	extern void ext4_free_group_clusters_set(struct super_block *sb,
3334	struct ext4_group_desc *bg,
3335	__u32 count);
3336	extern void ext4_free_inodes_set(struct super_block *sb,
3337	struct ext4_group_desc *bg, __u32 count);
3338	extern void ext4_used_dirs_set(struct super_block *sb,
3339	struct ext4_group_desc *bg, __u32 count);
3340	extern void ext4_itable_unused_set(struct super_block *sb,
3341	struct ext4_group_desc *bg, __u32 count);
3342	extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3343	struct ext4_group_desc *gdp);
3344	extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3345	struct ext4_group_desc *gdp);
3346	extern int ext4_register_li_request(struct super_block *sb,
3347	ext4_group_t first_not_zeroed);
3348
3349	static inline int ext4_has_group_desc_csum(struct super_block *sb)
3350	{
3351	return ext4_has_feature_gdt_csum(sb) \|\|
3352	ext4_has_feature_metadata_csum(sb);
3353	}
3354
3355	#define ext4_read_incompat_64bit_val(es, name) \
3356	(((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3357	? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) \| \
3358	le32_to_cpu(es->name##_lo))
3359
3360	static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3361	{
3362	return ext4_read_incompat_64bit_val(es, s_blocks_count);
3363	}
3364
3365	static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3366	{
3367	return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3368	}
3369
3370	static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3371	{
3372	return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3373	}
3374
3375	static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3376	ext4_fsblk_t blk)
3377	{
3378	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3379	es->s_blocks_count_hi = cpu_to_le32(blk >> `32`);
3380	}
3381
3382	static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3383	ext4_fsblk_t blk)
3384	{
3385	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3386	es->s_free_blocks_count_hi = cpu_to_le32(blk >> `32`);
3387	}
3388
3389	static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3390	ext4_fsblk_t blk)
3391	{
3392	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3393	es->s_r_blocks_count_hi = cpu_to_le32(blk >> `32`);
3394	}
3395
3396	static inline loff_t ext4_isize(struct super_block *sb,
3397	struct ext4_inode *raw_inode)
3398	{
3399	if (ext4_has_feature_largedir(sb) \|\|
3400	S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3401	return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << `32`) \|
3402	le32_to_cpu(raw_inode->i_size_lo);
3403
3404	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3405	}
3406
3407	static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3408	{
3409	raw_inode->i_size_lo = cpu_to_le32(i_size);
3410	raw_inode->i_size_high = cpu_to_le32(i_size >> `32`);
3411	}
3412
3413	/*
3414	* Reading s_groups_count requires using smp_rmb() afterwards. See
3415	* the locking protocol documented in the comments of ext4_group_add()
3416	* in resize.c
3417	*/
3418	static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3419	{
3420	ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3421
3422	smp_rmb();
3423	return ngroups;
3424	}
3425
3426	static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3427	ext4_group_t block_group)
3428	{
3429	return block_group >> sbi->s_log_groups_per_flex;
3430	}
3431
3432	static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3433	{
3434	return `1` << sbi->s_log_groups_per_flex;
3435	}
3436
3437	static inline loff_t ext4_get_maxbytes(struct inode *inode)
3438	{
3439	if (ext4_test_inode_flag(inode, bit: EXT4_INODE_EXTENTS))
3440	return inode->i_sb->s_maxbytes;
3441	return EXT4_SB(sb: inode->i_sb)->s_bitmap_maxbytes;
3442	}
3443
3444	#define ext4_std_error(sb, errno) \
3445	do { \
3446	if ((errno)) \
3447	__ext4_std_error((sb), __func__, __LINE__, (errno)); \
3448	} while (0)
3449
3450	#ifdef CONFIG_SMP
3451	/ Each CPU can accumulate percpu_counter_batch clusters in their local*
3452	* counters. So we need to make sure we have free clusters more
3453	* than percpu_counter_batch * nr_cpu_ids. Also add a window of 4 times.
3454	*/
3455	#define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3456	#else
3457	#define EXT4_FREECLUSTERS_WATERMARK 0
3458	#endif
3459
3460	/ Update i_disksize. Requires i_rwsem to avoid races with truncate /
3461	static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3462	{
3463	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3464	!inode_is_locked(inode));
3465	down_write(sem: &EXT4_I(inode)->i_data_sem);
3466	if (newsize > EXT4_I(inode)->i_disksize)
3467	WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3468	up_write(sem: &EXT4_I(inode)->i_data_sem);
3469	}
3470
3471	/ Update i_size, i_disksize. Requires i_rwsem to avoid races with truncate /
3472	static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3473	{
3474	int changed = `0`;
3475
3476	if (newsize > inode->i_size) {
3477	i_size_write(inode, i_size: newsize);
3478	changed = `1`;
3479	}
3480	if (newsize > EXT4_I(inode)->i_disksize) {
3481	ext4_update_i_disksize(inode, newsize);
3482	changed \|= `2`;
3483	}
3484	return changed;
3485	}
3486
3487	int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3488	loff_t len);
3489
3490	struct ext4_group_info {
3491	unsigned long bb_state;
3492	#ifdef AGGRESSIVE_CHECK
3493	unsigned long bb_check_counter;
3494	#endif
3495	struct rb_root bb_free_root;
3496	ext4_grpblk_t bb_first_free; / first free block /
3497	ext4_grpblk_t bb_free; / total free blocks /
3498	ext4_grpblk_t bb_fragments; / nr of freespace fragments /
3499	int bb_avg_fragment_size_order; / order of average*
3500	fragment in BG /*
3501	ext4_grpblk_t bb_largest_free_order;/ order of largest frag in BG /
3502	ext4_group_t bb_group; / Group number /
3503	struct list_head bb_prealloc_list;
3504	#ifdef DOUBLE_CHECK
3505	void *bb_bitmap;
3506	#endif
3507	struct rw_semaphore alloc_sem;
3508	ext4_grpblk_t bb_counters[]; / Nr of free power-of-two-block*
3509	* regions, index is order.
3510	* bb_counters[3] = 5 means
3511	* 5 free 8-block regions. */
3512	};
3513
3514	#define EXT4_GROUP_INFO_NEED_INIT_BIT 0
3515	#define EXT4_GROUP_INFO_WAS_TRIMMED_BIT 1
3516	#define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT 2
3517	#define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT 3
3518	#define EXT4_GROUP_INFO_BBITMAP_CORRUPT \
3519	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3520	#define EXT4_GROUP_INFO_IBITMAP_CORRUPT \
3521	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3522	#define EXT4_GROUP_INFO_BBITMAP_READ_BIT 4
3523
3524	#define EXT4_MB_GRP_NEED_INIT(grp) \
3525	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3526	#define EXT4_MB_GRP_BBITMAP_CORRUPT(grp) \
3527	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3528	#define EXT4_MB_GRP_IBITMAP_CORRUPT(grp) \
3529	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3530
3531	#define EXT4_MB_GRP_WAS_TRIMMED(grp) \
3532	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3533	#define EXT4_MB_GRP_SET_TRIMMED(grp) \
3534	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3535	#define EXT4_MB_GRP_CLEAR_TRIMMED(grp) \
3536	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3537	#define EXT4_MB_GRP_TEST_AND_SET_READ(grp) \
3538	(test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3539
3540	#define EXT4_MAX_CONTENTION 8
3541	#define EXT4_CONTENTION_THRESHOLD 2
3542
3543	static inline spinlock_t ext4_group_lock_ptr(struct* super_block *sb,
3544	ext4_group_t group)
3545	{
3546	return bgl_lock_ptr(bgl: EXT4_SB(sb)->s_blockgroup_lock, block_group: group);
3547	}
3548
3549	/*
3550	* Returns true if the filesystem is busy enough that attempts to
3551	* access the block group locks has run into contention.
3552	*/
3553	static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3554	{
3555	return (atomic_read(v: &sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3556	}
3557
3558	static inline bool ext4_try_lock_group(struct super_block *sb, ext4_group_t group)
3559	{
3560	if (!spin_trylock(lock: ext4_group_lock_ptr(sb, group)))
3561	return false;
3562	/*
3563	* We're able to grab the lock right away, so drop the lock
3564	* contention counter.
3565	*/
3566	atomic_add_unless(v: &EXT4_SB(sb)->s_lock_busy, a: -`1`, u: `0`);
3567	return true;
3568	}
3569
3570	static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3571	{
3572	if (!ext4_try_lock_group(sb, group)) {
3573	/*
3574	* The lock is busy, so bump the contention counter,
3575	* and then wait on the spin lock.
3576	*/
3577	atomic_add_unless(v: &EXT4_SB(sb)->s_lock_busy, a: `1`,
3578	EXT4_MAX_CONTENTION);
3579	spin_lock(lock: ext4_group_lock_ptr(sb, group));
3580	}
3581	}
3582
3583	static inline void ext4_unlock_group(struct super_block *sb,
3584	ext4_group_t group)
3585	{
3586	spin_unlock(lock: ext4_group_lock_ptr(sb, group));
3587	}
3588
3589	#ifdef CONFIG_QUOTA
3590	static inline bool ext4_quota_capable(struct super_block *sb)
3591	{
3592	return (test_opt(sb, QUOTA) \|\| ext4_has_feature_quota(sb));
3593	}
3594
3595	static inline bool ext4_is_quota_journalled(struct super_block *sb)
3596	{
3597	struct ext4_sb_info *sbi = EXT4_SB(sb);
3598
3599	return (ext4_has_feature_quota(sb) \|\|
3600	sbi->s_qf_names[USRQUOTA] \|\| sbi->s_qf_names[GRPQUOTA]);
3601	}
3602	int ext4_enable_quotas(struct super_block *sb);
3603	#endif
3604
3605	/*
3606	* Block validity checking
3607	*/
3608	#define ext4_check_indirect_blockref(inode, bh) \
3609	ext4_check_blockref(__func__, __LINE__, inode, \
3610	(__le32 *)(bh)->b_data, \
3611	EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3612
3613	#define ext4_ind_check_inode(inode) \
3614	ext4_check_blockref(__func__, __LINE__, inode, \
3615	EXT4_I(inode)->i_data, \
3616	EXT4_NDIR_BLOCKS)
3617
3618	/*
3619	* Inodes and files operations
3620	*/
3621
3622	/ dir.c /
3623	extern const struct file_operations ext4_dir_operations;
3624
3625	/ file.c /
3626	extern const struct inode_operations ext4_file_inode_operations;
3627	extern const struct file_operations ext4_file_operations;
3628	extern loff_t ext4_llseek(struct file file, loff_t offset, int* origin);
3629
3630	/ inline.c /
3631	extern int ext4_get_max_inline_size(struct inode *inode);
3632	extern int ext4_find_inline_data_nolock(struct inode *inode);
3633	extern int ext4_destroy_inline_data(handle_t handle, struct* inode *inode);
3634	extern void ext4_update_final_de(void de_buf, int* old_size, int new_size);
3635
3636	int ext4_readpage_inline(struct inode inode, struct* folio *folio);
3637	extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3638	struct inode *inode,
3639	loff_t pos, unsigned len,
3640	struct folio **foliop);
3641	int ext4_write_inline_data_end(struct inode inode, loff_t pos, unsigned* len,
3642	unsigned copied, struct folio *folio);
3643	extern int ext4_generic_write_inline_data(struct address_space *mapping,
3644	struct inode *inode,
3645	loff_t pos, unsigned len,
3646	struct folio **foliop,
3647	void **fsdata, bool da);
3648	extern int ext4_try_add_inline_entry(handle_t *handle,
3649	struct ext4_filename *fname,
3650	struct inode dir, struct* inode *inode);
3651	extern int ext4_try_create_inline_dir(handle_t *handle,
3652	struct inode *parent,
3653	struct inode *inode);
3654	extern int ext4_read_inline_dir(struct file *filp,
3655	struct dir_context *ctx,
3656	int *has_inline_data);
3657	extern int ext4_inlinedir_to_tree(struct file *dir_file,
3658	struct inode *dir, ext4_lblk_t block,
3659	struct dx_hash_info *hinfo,
3660	__u32 start_hash, __u32 start_minor_hash,
3661	int *has_inline_data);
3662	extern struct buffer_head ext4_find_inline_entry(struct* inode *dir,
3663	struct ext4_filename *fname,
3664	struct ext4_dir_entry_2 **res_dir,
3665	int *has_inline_data);
3666	extern int ext4_delete_inline_entry(handle_t *handle,
3667	struct inode *dir,
3668	struct ext4_dir_entry_2 *de_del,
3669	struct buffer_head *bh,
3670	int *has_inline_data);
3671	extern bool empty_inline_dir(struct inode dir, int* *has_inline_data);
3672	extern struct buffer_head ext4_get_first_inline_block(struct* inode *inode,
3673	struct ext4_dir_entry_2 **parent_de,
3674	int *retval);
3675	extern void ext4_read_inline_link(struct* inode *inode);
3676
3677	struct iomap;
3678	extern int ext4_inline_data_iomap(struct inode inode, struct* iomap *iomap);
3679
3680	extern int ext4_inline_data_truncate(struct inode inode, int* *has_inline);
3681
3682	extern int ext4_convert_inline_data(struct inode *inode);
3683
3684	static inline int ext4_has_inline_data(struct inode *inode)
3685	{
3686	return ext4_test_inode_flag(inode, bit: EXT4_INODE_INLINE_DATA) &&
3687	EXT4_I(inode)->i_inline_off;
3688	}
3689
3690	/ namei.c /
3691	extern const struct inode_operations ext4_dir_inode_operations;
3692	extern const struct inode_operations ext4_special_inode_operations;
3693	extern struct dentry ext4_get_parent(struct* dentry *child);
3694	extern int ext4_init_dirblock(handle_t handle, struct* inode *inode,
3695	struct buffer_head *dir_block,
3696	unsigned int parent_ino, void *inline_buf,
3697	int inline_size);
3698	extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3699	unsigned int blocksize);
3700	extern int ext4_handle_dirty_dirblock(handle_t handle, struct* inode *inode,
3701	struct buffer_head *bh);
3702	extern int __ext4_unlink(struct inode dir, const* struct qstr *d_name,
3703	struct inode inode, struct* dentry *dentry);
3704	extern int __ext4_link(struct inode dir, struct* inode *inode,
3705	struct dentry *dentry);
3706
3707	#define S_SHIFT 12
3708	static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + `1`] = {
3709	[S_IFREG >> S_SHIFT] = EXT4_FT_REG_FILE,
3710	[S_IFDIR >> S_SHIFT] = EXT4_FT_DIR,
3711	[S_IFCHR >> S_SHIFT] = EXT4_FT_CHRDEV,
3712	[S_IFBLK >> S_SHIFT] = EXT4_FT_BLKDEV,
3713	[S_IFIFO >> S_SHIFT] = EXT4_FT_FIFO,
3714	[S_IFSOCK >> S_SHIFT] = EXT4_FT_SOCK,
3715	[S_IFLNK >> S_SHIFT] = EXT4_FT_SYMLINK,
3716	};
3717
3718	static inline void ext4_set_de_type(struct super_block *sb,
3719	struct ext4_dir_entry_2 *de,
3720	umode_t mode) {
3721	if (ext4_has_feature_filetype(sb))
3722	de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3723	}
3724
3725	/ readpages.c /
3726	extern int ext4_mpage_readpages(struct inode *inode,
3727	struct readahead_control rac, struct* folio *folio);
3728	extern int __init ext4_init_post_read_processing(void);
3729	extern void ext4_exit_post_read_processing(void);
3730
3731	/ symlink.c /
3732	extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3733	extern const struct inode_operations ext4_symlink_inode_operations;
3734	extern const struct inode_operations ext4_fast_symlink_inode_operations;
3735
3736	/ sysfs.c /
3737	extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
3738	extern int ext4_register_sysfs(struct super_block *sb);
3739	extern void ext4_unregister_sysfs(struct super_block *sb);
3740	extern int __init ext4_init_sysfs(void);
3741	extern void ext4_exit_sysfs(void);
3742
3743	/ block_validity /
3744	extern void ext4_release_system_zone(struct super_block *sb);
3745	extern int ext4_setup_system_zone(struct super_block *sb);
3746	extern int __init ext4_init_system_zone(void);
3747	extern void ext4_exit_system_zone(void);
3748	extern int ext4_inode_block_valid(struct inode *inode,
3749	ext4_fsblk_t start_blk,
3750	unsigned int count);
3751	extern int ext4_check_blockref(const char , unsigned* int,
3752	struct inode , __le32 , unsigned int);
3753	extern int ext4_sb_block_valid(struct super_block sb, struct* inode *inode,
3754	ext4_fsblk_t start_blk, unsigned int count);
3755
3756
3757	/ extents.c /
3758	struct ext4_ext_path;
3759	struct ext4_extent;
3760
3761	/*
3762	* Maximum number of logical blocks in a file; ext4_extent's ee_block is
3763	* __le32.
3764	*/
3765	#define EXT_MAX_BLOCKS 0xffffffff
3766
3767	extern void ext4_ext_tree_init(handle_t handle, struct* inode *inode);
3768	extern int ext4_ext_index_trans_blocks(struct inode inode, int* extents);
3769	extern int ext4_ext_map_blocks(handle_t handle, struct* inode *inode,
3770	struct ext4_map_blocks map, int* flags);
3771	extern int ext4_ext_truncate(handle_t , struct* inode *);
3772	extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3773	ext4_lblk_t end);
3774	extern void ext4_ext_init(struct super_block *);
3775	extern void ext4_ext_release(struct super_block *);
3776	extern long ext4_fallocate(struct file file, int* mode, loff_t offset,
3777	loff_t len);
3778	extern int ext4_convert_unwritten_extents(handle_t handle, struct* inode *inode,
3779	loff_t offset, ssize_t len);
3780	extern int ext4_convert_unwritten_extents_atomic(handle_t *handle,
3781	struct inode *inode, loff_t offset, ssize_t len);
3782	extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3783	ext4_io_end_t *io_end);
3784	extern int ext4_map_blocks(handle_t handle, struct* inode *inode,
3785	struct ext4_map_blocks map, int* flags);
3786	extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3787	int num,
3788	struct ext4_ext_path *path);
3789	extern struct ext4_ext_path *ext4_ext_insert_extent(
3790	handle_t handle, struct* inode *inode,
3791	struct ext4_ext_path *path,
3792	struct ext4_extent newext, int* gb_flags);
3793	extern struct ext4_ext_path ext4_find_extent(struct* inode *, ext4_lblk_t,
3794	struct ext4_ext_path *,
3795	int flags);
3796	extern void ext4_free_ext_path(struct ext4_ext_path *);
3797	extern int ext4_ext_check_inode(struct inode *inode);
3798	extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3799	extern int ext4_fiemap(struct inode inode, struct* fiemap_extent_info *fieinfo,
3800	__u64 start, __u64 len);
3801	extern int ext4_get_es_cache(struct inode *inode,
3802	struct fiemap_extent_info *fieinfo,
3803	__u64 start, __u64 len);
3804	extern int ext4_ext_precache(struct inode *inode);
3805	extern int ext4_swap_extents(handle_t handle, struct* inode *inode1,
3806	struct inode *inode2, ext4_lblk_t lblk1,
3807	ext4_lblk_t lblk2, ext4_lblk_t count,
3808	int mark_unwritten,int *err);
3809	extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3810	extern int ext4_datasem_ensure_credits(handle_t handle, struct* inode *inode,
3811	int check_cred, int restart_cred,
3812	int revoke_cred);
3813	extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3814	extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3815	extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3816	int len, int unwritten, ext4_fsblk_t pblk);
3817	extern int ext4_ext_clear_bb(struct inode *inode);
3818
3819
3820	/ move_extent.c /
3821	extern void ext4_double_down_write_data_sem(struct inode *first,
3822	struct inode *second);
3823	extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3824	struct inode *donor_inode);
3825	extern int ext4_move_extents(struct file o_filp, struct* file *d_filp,
3826	__u64 start_orig, __u64 start_donor,
3827	__u64 len, __u64 *moved_len);
3828
3829	/ page-io.c /
3830	extern int __init ext4_init_pageio(void);
3831	extern void ext4_exit_pageio(void);
3832	extern ext4_io_end_t ext4_init_io_end(struct* inode *inode, gfp_t flags);
3833	extern ext4_io_end_t ext4_get_io_end(ext4_io_end_t io_end);
3834	extern int ext4_put_io_end(ext4_io_end_t *io_end);
3835	extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3836	extern void ext4_io_submit_init(struct ext4_io_submit *io,
3837	struct writeback_control *wbc);
3838	extern void ext4_end_io_rsv_work(struct work_struct *work);
3839	extern void ext4_io_submit(struct ext4_io_submit *io);
3840	int ext4_bio_write_folio(struct ext4_io_submit io, struct* folio *page,
3841	size_t len);
3842	extern struct ext4_io_end_vec ext4_alloc_io_end_vec(ext4_io_end_t io_end);
3843	extern struct ext4_io_end_vec ext4_last_io_end_vec(ext4_io_end_t io_end);
3844
3845	/ mmp.c /
3846	extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3847
3848	/ mmp.c /
3849	extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
3850
3851	/ verity.c /
3852	extern const struct fsverity_operations ext4_verityops;
3853
3854	/ orphan.c /
3855	extern int ext4_orphan_add(handle_t , struct* inode *);
3856	extern int ext4_orphan_del(handle_t , struct* inode *);
3857	extern void ext4_orphan_cleanup(struct super_block *sb,
3858	struct ext4_super_block *es);
3859	extern void ext4_release_orphan_info(struct super_block *sb);
3860	extern int ext4_init_orphan_info(struct super_block *sb);
3861	extern int ext4_orphan_file_empty(struct super_block *sb);
3862	extern void ext4_orphan_file_block_trigger(
3863	struct jbd2_buffer_trigger_type *triggers,
3864	struct buffer_head *bh,
3865	void *data, size_t size);
3866
3867	/*
3868	* Add new method to test whether block and inode bitmaps are properly
3869	* initialized. With uninit_bg reading the block from disk is not enough
3870	* to mark the bitmap uptodate. We need to also zero-out the bitmap
3871	*/
3872	#define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3873
3874	static inline int bitmap_uptodate(struct buffer_head *bh)
3875	{
3876	return (buffer_uptodate(bh) &&
3877	test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3878	}
3879	static inline void set_bitmap_uptodate(struct buffer_head *bh)
3880	{
3881	set_bit(BH_BITMAP_UPTODATE, addr: &(bh)->b_state);
3882	}
3883
3884	extern int ext4_resize_begin(struct super_block *sb);
3885	extern int ext4_resize_end(struct super_block *sb, bool update_backups);
3886
3887	static inline void ext4_set_io_unwritten_flag(struct ext4_io_end *io_end)
3888	{
3889	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN))
3890	io_end->flag \|= EXT4_IO_END_UNWRITTEN;
3891	}
3892
3893	static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3894	{
3895	if (io_end->flag & EXT4_IO_END_UNWRITTEN)
3896	io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3897	}
3898
3899	extern const struct iomap_ops ext4_iomap_ops;
3900	extern const struct iomap_ops ext4_iomap_overwrite_ops;
3901	extern const struct iomap_ops ext4_iomap_report_ops;
3902
3903	static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3904	{
3905	/*
3906	* If the buffer has the write error flag, we have failed
3907	* to write out data in the block. In this case, we don't
3908	* have to read the block because we may read the old data
3909	* successfully.
3910	*/
3911	if (buffer_write_io_error(bh))
3912	set_buffer_uptodate(bh);
3913	return buffer_uptodate(bh);
3914	}
3915
3916	static inline bool ext4_inode_can_atomic_write(struct inode *inode)
3917	{
3918
3919	return S_ISREG(inode->i_mode) &&
3920	ext4_test_inode_flag(inode, bit: EXT4_INODE_EXTENTS) &&
3921	EXT4_SB(sb: inode->i_sb)->s_awu_min > `0`;
3922	}
3923
3924	extern int ext4_block_write_begin(handle_t handle, struct* folio *folio,
3925	loff_t pos, unsigned len,
3926	get_block_t *get_block);
3927	#endif /* __KERNEL__ */
3928
3929	#define EFSBADCRC EBADMSG /* Bad CRC detected */
3930	#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
3931
3932	#endif /* _EXT4_H */
3933

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