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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 1992, 1993, 1994, 1995
4 * Remy Card ([email protected])
5 * Laboratoire MASI - Institut Blaise Pascal
6 * Universite Pierre et Marie Curie (Paris VI)
7 *
8 * from
9 *
10 * linux/include/linux/minix_fs.h
11 *
12 * Copyright (C) 1991, 1992 Linus Torvalds
13 */
14#include <linux/fs.h>
15#include <linux/ext2_fs.h>
16#include <linux/blockgroup_lock.h>
17#include <linux/percpu_counter.h>
18#include <linux/rbtree.h>
19#include <linux/mm.h>
20#include <linux/highmem.h>
21
22/* XXX Here for now... not interested in restructing headers JUST now */
23
24/* data type for block offset of block group */
25typedef int ext2_grpblk_t;
26
27/* data type for filesystem-wide blocks number */
28typedef unsigned long ext2_fsblk_t;
29
30#define E2FSBLK "%lu"
31
32struct ext2_reserve_window {
33 ext2_fsblk_t _rsv_start; /* First byte reserved */
34 ext2_fsblk_t _rsv_end; /* Last byte reserved or 0 */
35};
36
37struct ext2_reserve_window_node {
38 struct rb_node rsv_node;
39 __u32 rsv_goal_size;
40 __u32 rsv_alloc_hit;
41 struct ext2_reserve_window rsv_window;
42};
43
44struct ext2_block_alloc_info {
45 /* information about reservation window */
46 struct ext2_reserve_window_node rsv_window_node;
47 /*
48 * was i_next_alloc_block in ext2_inode_info
49 * is the logical (file-relative) number of the
50 * most-recently-allocated block in this file.
51 * We use this for detecting linearly ascending allocation requests.
52 */
53 __u32 last_alloc_logical_block;
54 /*
55 * Was i_next_alloc_goal in ext2_inode_info
56 * is the *physical* companion to i_next_alloc_block.
57 * it is the physical block number of the block which was most-recently
58 * allocated to this file. This gives us the goal (target) for the next
59 * allocation when we detect linearly ascending requests.
60 */
61 ext2_fsblk_t last_alloc_physical_block;
62};
63
64#define rsv_start rsv_window._rsv_start
65#define rsv_end rsv_window._rsv_end
66
67struct mb_cache;
68
69/*
70 * second extended-fs super-block data in memory
71 */
72struct ext2_sb_info {
73 unsigned long s_inodes_per_block;/* Number of inodes per block */
74 unsigned long s_blocks_per_group;/* Number of blocks in a group */
75 unsigned long s_inodes_per_group;/* Number of inodes in a group */
76 unsigned long s_itb_per_group; /* Number of inode table blocks per group */
77 unsigned long s_gdb_count; /* Number of group descriptor blocks */
78 unsigned long s_desc_per_block; /* Number of group descriptors per block */
79 unsigned long s_groups_count; /* Number of groups in the fs */
80 unsigned long s_overhead_last __guarded_by(&s_lock); /* Last calculated overhead */
81 unsigned long s_blocks_last __guarded_by(&s_lock); /* Last seen block count */
82 struct buffer_head * s_sbh; /* Buffer containing the super block */
83 struct ext2_super_block * s_es; /* Pointer to the super block in the buffer */
84 struct buffer_head ** s_group_desc;
85 unsigned long s_mount_opt;
86 unsigned long s_sb_block;
87 kuid_t s_resuid;
88 kgid_t s_resgid;
89 unsigned short s_mount_state __guarded_by(&s_lock);
90 unsigned short s_pad;
91 int s_addr_per_block_bits;
92 int s_desc_per_block_bits;
93 int s_inode_size;
94 int s_first_ino;
95 spinlock_t s_next_gen_lock;
96 u32 s_next_generation __guarded_by(&s_next_gen_lock);
97 unsigned long s_dir_count;
98 u8 *s_debts;
99 struct percpu_counter s_freeblocks_counter;
100 struct percpu_counter s_freeinodes_counter;
101 struct percpu_counter s_dirs_counter;
102 struct blockgroup_lock *s_blockgroup_lock;
103 /* root of the per fs reservation window tree */
104 spinlock_t s_rsv_window_lock;
105 struct rb_root s_rsv_window_root __guarded_by(&s_rsv_window_lock);
106 struct ext2_reserve_window_node s_rsv_window_head;
107 /*
108 * s_lock protects against concurrent modifications of s_mount_state,
109 * s_blocks_last, s_overhead_last and the content of superblock's
110 * buffer pointed to by sbi->s_es.
111 *
112 * Note: It is used in ext2_show_options() to provide a consistent view
113 * of the mount options.
114 */
115 spinlock_t s_lock;
116 struct mb_cache *s_ea_block_cache;
117};
118
119static inline spinlock_t *
120sb_bgl_lock(struct ext2_sb_info *sbi, unsigned int block_group)
121{
122 return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);
123}
124
125/*
126 * Define EXT2FS_DEBUG to produce debug messages
127 */
128#undef EXT2FS_DEBUG
129
130/*
131 * Define EXT2_RESERVATION to reserve data blocks for expanding files
132 */
133#define EXT2_DEFAULT_RESERVE_BLOCKS 8
134/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
135#define EXT2_MAX_RESERVE_BLOCKS 1027
136#define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
137/*
138 * The second extended file system version
139 */
140#define EXT2FS_DATE "95/08/09"
141#define EXT2FS_VERSION "0.5b"
142
143/*
144 * Debug code
145 */
146#ifdef EXT2FS_DEBUG
147# define ext2_debug(f, a...) { \
148 printk ("EXT2-fs DEBUG (%s, %d): %s:", \
149 __FILE__, __LINE__, __func__); \
150 printk (f, ## a); \
151 }
152#else
153# define ext2_debug(f, a...) /**/
154#endif
155
156/*
157 * Special inode numbers
158 */
159#define EXT2_BAD_INO 1 /* Bad blocks inode */
160#define EXT2_ROOT_INO 2 /* Root inode */
161#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
162#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
163
164/* First non-reserved inode for old ext2 filesystems */
165#define EXT2_GOOD_OLD_FIRST_INO 11
166
167static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
168{
169 return sb->s_fs_info;
170}
171
172/*
173 * Macro-instructions used to manage several block sizes
174 */
175#define EXT2_MIN_BLOCK_SIZE 1024
176#define EXT2_MAX_BLOCK_SIZE 65536
177#define EXT2_MIN_BLOCK_LOG_SIZE 10
178#define EXT2_MAX_BLOCK_LOG_SIZE 16
179#define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
180#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
181#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
182#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
183#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
184#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
185
186/*
187 * Structure of a blocks group descriptor
188 */
189struct ext2_group_desc
190{
191 __le32 bg_block_bitmap; /* Blocks bitmap block */
192 __le32 bg_inode_bitmap; /* Inodes bitmap block */
193 __le32 bg_inode_table; /* Inodes table block */
194 __le16 bg_free_blocks_count; /* Free blocks count */
195 __le16 bg_free_inodes_count; /* Free inodes count */
196 __le16 bg_used_dirs_count; /* Directories count */
197 __le16 bg_pad;
198 __le32 bg_reserved[3];
199};
200
201/*
202 * Macro-instructions used to manage group descriptors
203 */
204#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
205#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
206#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
207#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
208
209/*
210 * Constants relative to the data blocks
211 */
212#define EXT2_NDIR_BLOCKS 12
213#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
214#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
215#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
216#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
217
218/*
219 * Inode flags (GETFLAGS/SETFLAGS)
220 */
221#define EXT2_SECRM_FL FS_SECRM_FL /* Secure deletion */
222#define EXT2_UNRM_FL FS_UNRM_FL /* Undelete */
223#define EXT2_COMPR_FL FS_COMPR_FL /* Compress file */
224#define EXT2_SYNC_FL FS_SYNC_FL /* Synchronous updates */
225#define EXT2_IMMUTABLE_FL FS_IMMUTABLE_FL /* Immutable file */
226#define EXT2_APPEND_FL FS_APPEND_FL /* writes to file may only append */
227#define EXT2_NODUMP_FL FS_NODUMP_FL /* do not dump file */
228#define EXT2_NOATIME_FL FS_NOATIME_FL /* do not update atime */
229/* Reserved for compression usage... */
230#define EXT2_DIRTY_FL FS_DIRTY_FL
231#define EXT2_COMPRBLK_FL FS_COMPRBLK_FL /* One or more compressed clusters */
232#define EXT2_NOCOMP_FL FS_NOCOMP_FL /* Don't compress */
233#define EXT2_ECOMPR_FL FS_ECOMPR_FL /* Compression error */
234/* End compression flags --- maybe not all used */
235#define EXT2_BTREE_FL FS_BTREE_FL /* btree format dir */
236#define EXT2_INDEX_FL FS_INDEX_FL /* hash-indexed directory */
237#define EXT2_IMAGIC_FL FS_IMAGIC_FL /* AFS directory */
238#define EXT2_JOURNAL_DATA_FL FS_JOURNAL_DATA_FL /* Reserved for ext3 */
239#define EXT2_NOTAIL_FL FS_NOTAIL_FL /* file tail should not be merged */
240#define EXT2_DIRSYNC_FL FS_DIRSYNC_FL /* dirsync behaviour (directories only) */
241#define EXT2_TOPDIR_FL FS_TOPDIR_FL /* Top of directory hierarchies*/
242#define EXT2_RESERVED_FL FS_RESERVED_FL /* reserved for ext2 lib */
243
244#define EXT2_FL_USER_VISIBLE FS_FL_USER_VISIBLE /* User visible flags */
245#define EXT2_FL_USER_MODIFIABLE FS_FL_USER_MODIFIABLE /* User modifiable flags */
246
247/* Flags that should be inherited by new inodes from their parent. */
248#define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\
249 EXT2_SYNC_FL | EXT2_NODUMP_FL |\
250 EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\
251 EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\
252 EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)
253
254/* Flags that are appropriate for regular files (all but dir-specific ones). */
255#define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))
256
257/* Flags that are appropriate for non-directories/regular files. */
258#define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)
259
260/* Mask out flags that are inappropriate for the given type of inode. */
261static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
262{
263 if (S_ISDIR(mode))
264 return flags;
265 else if (S_ISREG(mode))
266 return flags & EXT2_REG_FLMASK;
267 else
268 return flags & EXT2_OTHER_FLMASK;
269}
270
271/*
272 * ioctl commands
273 */
274#define EXT2_IOC_GETVERSION FS_IOC_GETVERSION
275#define EXT2_IOC_SETVERSION FS_IOC_SETVERSION
276#define EXT2_IOC_GETRSVSZ _IOR('f', 5, long)
277#define EXT2_IOC_SETRSVSZ _IOW('f', 6, long)
278
279/*
280 * ioctl commands in 32 bit emulation
281 */
282#define EXT2_IOC32_GETVERSION FS_IOC32_GETVERSION
283#define EXT2_IOC32_SETVERSION FS_IOC32_SETVERSION
284
285/*
286 * Structure of an inode on the disk
287 */
288struct ext2_inode {
289 __le16 i_mode; /* File mode */
290 __le16 i_uid; /* Low 16 bits of Owner Uid */
291 __le32 i_size; /* Size in bytes */
292 __le32 i_atime; /* Access time */
293 __le32 i_ctime; /* Creation time */
294 __le32 i_mtime; /* Modification time */
295 __le32 i_dtime; /* Deletion Time */
296 __le16 i_gid; /* Low 16 bits of Group Id */
297 __le16 i_links_count; /* Links count */
298 __le32 i_blocks; /* Blocks count */
299 __le32 i_flags; /* File flags */
300 union {
301 struct {
302 __le32 l_i_reserved1;
303 } linux1;
304 struct {
305 __le32 h_i_translator;
306 } hurd1;
307 struct {
308 __le32 m_i_reserved1;
309 } masix1;
310 } osd1; /* OS dependent 1 */
311 __le32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
312 __le32 i_generation; /* File version (for NFS) */
313 __le32 i_file_acl; /* File ACL */
314 __le32 i_dir_acl; /* Directory ACL */
315 __le32 i_faddr; /* Fragment address */
316 union {
317 struct {
318 __u8 l_i_frag; /* Fragment number */
319 __u8 l_i_fsize; /* Fragment size */
320 __u16 i_pad1;
321 __le16 l_i_uid_high; /* these 2 fields */
322 __le16 l_i_gid_high; /* were reserved2[0] */
323 __u32 l_i_reserved2;
324 } linux2;
325 struct {
326 __u8 h_i_frag; /* Fragment number */
327 __u8 h_i_fsize; /* Fragment size */
328 __le16 h_i_mode_high;
329 __le16 h_i_uid_high;
330 __le16 h_i_gid_high;
331 __le32 h_i_author;
332 } hurd2;
333 struct {
334 __u8 m_i_frag; /* Fragment number */
335 __u8 m_i_fsize; /* Fragment size */
336 __u16 m_pad1;
337 __u32 m_i_reserved2[2];
338 } masix2;
339 } osd2; /* OS dependent 2 */
340};
341
342#define i_size_high i_dir_acl
343
344#define i_reserved1 osd1.linux1.l_i_reserved1
345#define i_frag osd2.linux2.l_i_frag
346#define i_fsize osd2.linux2.l_i_fsize
347#define i_uid_low i_uid
348#define i_gid_low i_gid
349#define i_uid_high osd2.linux2.l_i_uid_high
350#define i_gid_high osd2.linux2.l_i_gid_high
351#define i_reserved2 osd2.linux2.l_i_reserved2
352
353/*
354 * File system states
355 */
356#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
357#define EXT2_ERROR_FS 0x0002 /* Errors detected */
358
359/*
360 * Mount flags
361 */
362#define EXT2_MOUNT_OLDALLOC 0x000002 /* Don't use the new Orlov allocator */
363#define EXT2_MOUNT_GRPID 0x000004 /* Create files with directory's group */
364#define EXT2_MOUNT_DEBUG 0x000008 /* Some debugging messages */
365#define EXT2_MOUNT_ERRORS_CONT 0x000010 /* Continue on errors */
366#define EXT2_MOUNT_ERRORS_RO 0x000020 /* Remount fs ro on errors */
367#define EXT2_MOUNT_ERRORS_PANIC 0x000040 /* Panic on errors */
368#define EXT2_MOUNT_ERRORS_MASK 0x000070
369#define EXT2_MOUNT_MINIX_DF 0x000080 /* Mimics the Minix statfs */
370#define EXT2_MOUNT_NOBH 0x000100 /* No buffer_heads */
371#define EXT2_MOUNT_NO_UID32 0x000200 /* Disable 32-bit UIDs */
372#define EXT2_MOUNT_XATTR_USER 0x004000 /* Extended user attributes */
373#define EXT2_MOUNT_POSIX_ACL 0x008000 /* POSIX Access Control Lists */
374#define EXT2_MOUNT_USRQUOTA 0x020000 /* user quota */
375#define EXT2_MOUNT_GRPQUOTA 0x040000 /* group quota */
376#define EXT2_MOUNT_RESERVATION 0x080000 /* Preallocation */
377
378
379#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
380#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
381#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
382 EXT2_MOUNT_##opt)
383/*
384 * Maximal mount counts between two filesystem checks
385 */
386#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
387#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
388
389/*
390 * Behaviour when detecting errors
391 */
392#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
393#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
394#define EXT2_ERRORS_PANIC 3 /* Panic */
395#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
396
397/*
398 * Allocation flags
399 */
400#define EXT2_ALLOC_NORESERVE 0x1 /* Do not use reservation
401 * window for allocation */
402
403/*
404 * Structure of the super block
405 */
406struct ext2_super_block {
407 __le32 s_inodes_count; /* Inodes count */
408 __le32 s_blocks_count; /* Blocks count */
409 __le32 s_r_blocks_count; /* Reserved blocks count */
410 __le32 s_free_blocks_count; /* Free blocks count */
411 __le32 s_free_inodes_count; /* Free inodes count */
412 __le32 s_first_data_block; /* First Data Block */
413 __le32 s_log_block_size; /* Block size */
414 __le32 s_log_frag_size; /* Fragment size */
415 __le32 s_blocks_per_group; /* # Blocks per group */
416 __le32 s_frags_per_group; /* # Fragments per group */
417 __le32 s_inodes_per_group; /* # Inodes per group */
418 __le32 s_mtime; /* Mount time */
419 __le32 s_wtime; /* Write time */
420 __le16 s_mnt_count; /* Mount count */
421 __le16 s_max_mnt_count; /* Maximal mount count */
422 __le16 s_magic; /* Magic signature */
423 __le16 s_state; /* File system state */
424 __le16 s_errors; /* Behaviour when detecting errors */
425 __le16 s_minor_rev_level; /* minor revision level */
426 __le32 s_lastcheck; /* time of last check */
427 __le32 s_checkinterval; /* max. time between checks */
428 __le32 s_creator_os; /* OS */
429 __le32 s_rev_level; /* Revision level */
430 __le16 s_def_resuid; /* Default uid for reserved blocks */
431 __le16 s_def_resgid; /* Default gid for reserved blocks */
432 /*
433 * These fields are for EXT2_DYNAMIC_REV superblocks only.
434 *
435 * Note: the difference between the compatible feature set and
436 * the incompatible feature set is that if there is a bit set
437 * in the incompatible feature set that the kernel doesn't
438 * know about, it should refuse to mount the filesystem.
439 *
440 * e2fsck's requirements are more strict; if it doesn't know
441 * about a feature in either the compatible or incompatible
442 * feature set, it must abort and not try to meddle with
443 * things it doesn't understand...
444 */
445 __le32 s_first_ino; /* First non-reserved inode */
446 __le16 s_inode_size; /* size of inode structure */
447 __le16 s_block_group_nr; /* block group # of this superblock */
448 __le32 s_feature_compat; /* compatible feature set */
449 __le32 s_feature_incompat; /* incompatible feature set */
450 __le32 s_feature_ro_compat; /* readonly-compatible feature set */
451 __u8 s_uuid[16]; /* 128-bit uuid for volume */
452 char s_volume_name[16]; /* volume name */
453 char s_last_mounted[64]; /* directory where last mounted */
454 __le32 s_algorithm_usage_bitmap; /* For compression */
455 /*
456 * Performance hints. Directory preallocation should only
457 * happen if the EXT2_COMPAT_PREALLOC flag is on.
458 */
459 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
460 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
461 __u16 s_padding1;
462 /*
463 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
464 */
465 __u8 s_journal_uuid[16]; /* uuid of journal superblock */
466 __u32 s_journal_inum; /* inode number of journal file */
467 __u32 s_journal_dev; /* device number of journal file */
468 __u32 s_last_orphan; /* start of list of inodes to delete */
469 __u32 s_hash_seed[4]; /* HTREE hash seed */
470 __u8 s_def_hash_version; /* Default hash version to use */
471 __u8 s_reserved_char_pad;
472 __u16 s_reserved_word_pad;
473 __le32 s_default_mount_opts;
474 __le32 s_first_meta_bg; /* First metablock block group */
475 __u32 s_reserved[190]; /* Padding to the end of the block */
476};
477
478/*
479 * Codes for operating systems
480 */
481#define EXT2_OS_LINUX 0
482#define EXT2_OS_HURD 1
483#define EXT2_OS_MASIX 2
484#define EXT2_OS_FREEBSD 3
485#define EXT2_OS_LITES 4
486
487/*
488 * Revision levels
489 */
490#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
491#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
492
493#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
494#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
495
496#define EXT2_GOOD_OLD_INODE_SIZE 128
497
498/*
499 * Feature set definitions
500 */
501
502#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
503 ( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
504#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
505 ( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
506#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
507 ( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
508#define EXT2_SET_COMPAT_FEATURE(sb,mask) \
509 EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
510#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask) \
511 EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
512#define EXT2_SET_INCOMPAT_FEATURE(sb,mask) \
513 EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
514#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask) \
515 EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
516#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
517 EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
518#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask) \
519 EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
520
521#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
522#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
523#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
524#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
525#define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
526#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
527#define EXT2_FEATURE_COMPAT_ANY 0xffffffff
528
529#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
530#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
531#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
532#define EXT2_FEATURE_RO_COMPAT_ANY 0xffffffff
533
534#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
535#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
536#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
537#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
538#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
539#define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
540
541#define EXT2_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
542#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
543 EXT2_FEATURE_INCOMPAT_META_BG)
544#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
545 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
546 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
547#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED ~EXT2_FEATURE_RO_COMPAT_SUPP
548#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED ~EXT2_FEATURE_INCOMPAT_SUPP
549
550/*
551 * Default values for user and/or group using reserved blocks
552 */
553#define EXT2_DEF_RESUID 0
554#define EXT2_DEF_RESGID 0
555
556/*
557 * Default mount options
558 */
559#define EXT2_DEFM_DEBUG 0x0001
560#define EXT2_DEFM_BSDGROUPS 0x0002
561#define EXT2_DEFM_XATTR_USER 0x0004
562#define EXT2_DEFM_ACL 0x0008
563#define EXT2_DEFM_UID16 0x0010
564 /* Not used by ext2, but reserved for use by ext3 */
565#define EXT3_DEFM_JMODE 0x0060
566#define EXT3_DEFM_JMODE_DATA 0x0020
567#define EXT3_DEFM_JMODE_ORDERED 0x0040
568#define EXT3_DEFM_JMODE_WBACK 0x0060
569
570/*
571 * Structure of a directory entry
572 */
573
574struct ext2_dir_entry {
575 __le32 inode; /* Inode number */
576 __le16 rec_len; /* Directory entry length */
577 __le16 name_len; /* Name length */
578 char name[]; /* File name, up to EXT2_NAME_LEN */
579};
580
581/*
582 * The new version of the directory entry. Since EXT2 structures are
583 * stored in intel byte order, and the name_len field could never be
584 * bigger than 255 chars, it's safe to reclaim the extra byte for the
585 * file_type field.
586 */
587struct ext2_dir_entry_2 {
588 __le32 inode; /* Inode number */
589 __le16 rec_len; /* Directory entry length */
590 __u8 name_len; /* Name length */
591 __u8 file_type;
592 char name[]; /* File name, up to EXT2_NAME_LEN */
593};
594
595/*
596 * EXT2_DIR_PAD defines the directory entries boundaries
597 *
598 * NOTE: It must be a multiple of 4
599 */
600#define EXT2_DIR_PAD 4
601#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
602#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
603 ~EXT2_DIR_ROUND)
604#define EXT2_MAX_REC_LEN ((1<<16)-1)
605
606static inline void verify_offsets(void)
607{
608#define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));
609 A(EXT2_SB_MAGIC_OFFSET, s_magic);
610 A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);
611 A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);
612#undef A
613}
614
615/*
616 * ext2 mount options
617 */
618struct ext2_mount_options {
619 unsigned long s_mount_opt;
620 kuid_t s_resuid;
621 kgid_t s_resgid;
622};
623
624/*
625 * second extended file system inode data in memory
626 */
627struct ext2_inode_info {
628 __le32 i_data[15];
629 __u32 i_flags;
630 __u32 i_faddr;
631 __u8 i_frag_no;
632 __u8 i_frag_size;
633 __u16 i_state;
634 __u32 i_file_acl;
635 __u32 i_dir_acl;
636 __u32 i_dtime;
637
638 /*
639 * i_block_group is the number of the block group which contains
640 * this file's inode. Constant across the lifetime of the inode,
641 * it is used for making block allocation decisions - we try to
642 * place a file's data blocks near its inode block, and new inodes
643 * near to their parent directory's inode.
644 */
645 __u32 i_block_group;
646
647 /* block reservation info */
648 struct ext2_block_alloc_info *i_block_alloc_info;
649
650 __u32 i_dir_start_lookup;
651#ifdef CONFIG_EXT2_FS_XATTR
652 /*
653 * Extended attributes can be read independently of the main file
654 * data. Taking i_mutex even when reading would cause contention
655 * between readers of EAs and writers of regular file data, so
656 * instead we synchronize on xattr_sem when reading or changing
657 * EAs.
658 */
659 struct rw_semaphore xattr_sem;
660#endif
661 rwlock_t i_meta_lock;
662
663 /*
664 * truncate_mutex is for serialising ext2_truncate() against
665 * ext2_getblock(). It also protects the internals of the inode's
666 * reservation data structures: ext2_reserve_window and
667 * ext2_reserve_window_node.
668 */
669 struct mutex truncate_mutex;
670 struct inode vfs_inode;
671 struct list_head i_orphan; /* unlinked but open inodes */
672#ifdef CONFIG_QUOTA
673 struct dquot __rcu *i_dquot[MAXQUOTAS];
674#endif
675 struct mapping_metadata_bhs i_metadata_bhs;
676};
677
678/*
679 * Inode dynamic state flags
680 */
681#define EXT2_STATE_NEW 0x00000001 /* inode is newly created */
682
683
684/*
685 * Function prototypes
686 */
687
688/*
689 * Ok, these declarations are also in <linux/kernel.h> but none of the
690 * ext2 source programs needs to include it so they are duplicated here.
691 */
692
693static inline struct ext2_inode_info *EXT2_I(struct inode *inode)
694{
695 return container_of(inode, struct ext2_inode_info, vfs_inode);
696}
697
698/* balloc.c */
699extern int ext2_bg_has_super(struct super_block *sb, int group);
700extern unsigned long ext2_bg_num_gdb(struct super_block *sb, int group);
701extern ext2_fsblk_t ext2_new_blocks(struct inode *, ext2_fsblk_t,
702 unsigned long *, int *, unsigned int);
703extern int ext2_data_block_valid(struct ext2_sb_info *sbi, ext2_fsblk_t start_blk,
704 unsigned int count);
705extern void ext2_free_blocks(struct inode *, ext2_fsblk_t, unsigned long);
706extern unsigned long ext2_count_free_blocks (struct super_block *);
707extern unsigned long ext2_count_dirs (struct super_block *);
708extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
709 unsigned int block_group,
710 struct buffer_head ** bh);
711extern void ext2_discard_reservation (struct inode *);
712extern int ext2_should_retry_alloc(struct super_block *sb, int *retries);
713extern void ext2_init_block_alloc_info(struct inode *inode)
714 __must_hold(&EXT2_I(inode)->truncate_mutex);
715extern void ext2_rsv_window_add(struct super_block *sb, struct ext2_reserve_window_node *rsv)
716 __must_hold(&EXT2_SB(sb)->s_rsv_window_lock);
717
718/* dir.c */
719int ext2_add_link(struct dentry *, struct inode *);
720int ext2_inode_by_name(struct inode *dir,
721 const struct qstr *child, ino_t *ino);
722int ext2_make_empty(struct inode *, struct inode *);
723struct ext2_dir_entry_2 *ext2_find_entry(struct inode *, const struct qstr *,
724 struct folio **foliop);
725int ext2_delete_entry(struct ext2_dir_entry_2 *dir, struct folio *folio);
726int ext2_empty_dir(struct inode *);
727struct ext2_dir_entry_2 *ext2_dotdot(struct inode *dir, struct folio **foliop);
728int ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
729 struct folio *folio, struct inode *inode, bool update_times);
730
731/* ialloc.c */
732extern struct inode * ext2_new_inode (struct inode *, umode_t, const struct qstr *);
733extern void ext2_free_inode (struct inode *);
734extern unsigned long ext2_count_free_inodes (struct super_block *);
735extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
736
737/* inode.c */
738extern struct inode *ext2_iget (struct super_block *, unsigned long);
739extern int ext2_write_inode (struct inode *, struct writeback_control *);
740extern int ext2_sync_inode_metadata(struct inode *, struct writeback_control *);
741extern void ext2_evict_inode(struct inode *);
742void ext2_write_failed(struct address_space *mapping, loff_t to);
743extern int ext2_get_block(struct inode *, sector_t, struct buffer_head *, int);
744extern int ext2_setattr (const struct mnt_idmap *, struct dentry *, struct iattr *);
745extern int ext2_getattr (const struct mnt_idmap *, const struct path *,
746 struct kstat *, u32, unsigned int);
747extern void ext2_set_inode_flags(struct inode *inode);
748extern int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
749 u64 start, u64 len);
750
751/* ioctl.c */
752extern int ext2_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
753extern int ext2_fileattr_set(const struct mnt_idmap *idmap,
754 struct dentry *dentry, struct file_kattr *fa);
755extern long ext2_ioctl(struct file *, unsigned int, unsigned long);
756extern long ext2_compat_ioctl(struct file *, unsigned int, unsigned long);
757
758/* namei.c */
759struct dentry *ext2_get_parent(struct dentry *child);
760
761/* super.c */
762extern __printf(3, 4)
763void ext2_error(struct super_block *, const char *, const char *, ...);
764extern __printf(3, 4)
765void ext2_msg(struct super_block *, const char *, const char *, ...);
766extern void ext2_update_dynamic_rev(struct super_block *sb)
767 __must_hold(&EXT2_SB(sb)->s_lock);
768extern void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
769 int wait);
770
771/*
772 * Inodes and files operations
773 */
774
775/* dir.c */
776extern const struct file_operations ext2_dir_operations;
777
778/* file.c */
779extern const struct inode_operations ext2_file_inode_operations;
780extern const struct file_operations ext2_file_operations;
781
782/* inode.c */
783extern void ext2_set_file_ops(struct inode *inode);
784extern const struct address_space_operations ext2_aops;
785extern const struct iomap_ops ext2_iomap_ops;
786
787/* namei.c */
788extern const struct inode_operations ext2_dir_inode_operations;
789extern const struct inode_operations ext2_special_inode_operations;
790
791/* symlink.c */
792extern const struct inode_operations ext2_fast_symlink_inode_operations;
793extern const struct inode_operations ext2_symlink_inode_operations;
794
795static inline ext2_fsblk_t
796ext2_group_first_block_no(struct super_block *sb, unsigned long group_no)
797{
798 return group_no * (ext2_fsblk_t)EXT2_BLOCKS_PER_GROUP(sb) +
799 le32_to_cpu(EXT2_SB(sb)->s_es->s_first_data_block);
800}
801
802static inline ext2_fsblk_t
803ext2_group_last_block_no(struct super_block *sb, unsigned long group_no)
804{
805 struct ext2_sb_info *sbi = EXT2_SB(sb);
806
807 if (group_no == sbi->s_groups_count - 1)
808 return le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
809 else
810 return ext2_group_first_block_no(sb, group_no) +
811 EXT2_BLOCKS_PER_GROUP(sb) - 1;
812}
813
814#define ext2_set_bit __test_and_set_bit_le
815#define ext2_clear_bit __test_and_clear_bit_le
816#define ext2_test_bit test_bit_le
817#define ext2_find_first_zero_bit find_first_zero_bit_le
818#define ext2_find_next_zero_bit find_next_zero_bit_le