1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/fs/ext2/super.c
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/fs/minix/inode.c
13 *
14 * Copyright (C) 1991, 1992 Linus Torvalds
15 *
16 * Big-endian to little-endian byte-swapping/bitmaps by
17 * David S. Miller (davem@caip.rutgers.edu), 1995
18 */
19
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/slab.h>
24 #include <linux/init.h>
25 #include <linux/blkdev.h>
26 #include <linux/fs_context.h>
27 #include <linux/fs_parser.h>
28 #include <linux/random.h>
29 #include <linux/buffer_head.h>
30 #include <linux/exportfs.h>
31 #include <linux/vfs.h>
32 #include <linux/seq_file.h>
33 #include <linux/mount.h>
34 #include <linux/log2.h>
35 #include <linux/quotaops.h>
36 #include <linux/uaccess.h>
37 #include <linux/dax.h>
38 #include <linux/iversion.h>
39 #include "ext2.h"
40 #include "xattr.h"
41 #include "acl.h"
42
43 static void ext2_write_super(struct super_block *sb);
44 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
45 static int ext2_sync_fs(struct super_block *sb, int wait);
46 static int ext2_freeze(struct super_block *sb);
47 static int ext2_unfreeze(struct super_block *sb);
48
ext2_error(struct super_block * sb,const char * function,const char * fmt,...)49 void ext2_error(struct super_block *sb, const char *function,
50 const char *fmt, ...)
51 {
52 struct va_format vaf;
53 va_list args;
54 struct ext2_sb_info *sbi = EXT2_SB(sb);
55 struct ext2_super_block *es = sbi->s_es;
56
57 if (!sb_rdonly(sb)) {
58 spin_lock(&sbi->s_lock);
59 sbi->s_mount_state |= EXT2_ERROR_FS;
60 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
61 spin_unlock(&sbi->s_lock);
62 ext2_sync_super(sb, es, 1);
63 }
64
65 va_start(args, fmt);
66
67 vaf.fmt = fmt;
68 vaf.va = &args;
69
70 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
71 sb->s_id, function, &vaf);
72
73 va_end(args);
74
75 if (test_opt(sb, ERRORS_PANIC))
76 panic("EXT2-fs: panic from previous error\n");
77 if (!sb_rdonly(sb) && test_opt(sb, ERRORS_RO)) {
78 ext2_msg(sb, KERN_CRIT,
79 "error: remounting filesystem read-only");
80 sb->s_flags |= SB_RDONLY;
81 }
82 }
83
ext2_msg_fc(struct fs_context * fc,const char * prefix,const char * fmt,...)84 static void ext2_msg_fc(struct fs_context *fc, const char *prefix,
85 const char *fmt, ...)
86 {
87 struct va_format vaf;
88 va_list args;
89 const char *s_id;
90
91 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
92 s_id = fc->root->d_sb->s_id;
93 } else {
94 /* get last path component of source */
95 s_id = strrchr(fc->source, '/');
96 if (s_id)
97 s_id++;
98 else
99 s_id = fc->source;
100 }
101 va_start(args, fmt);
102
103 vaf.fmt = fmt;
104 vaf.va = &args;
105
106 printk("%sEXT2-fs (%s): %pV\n", prefix, s_id, &vaf);
107
108 va_end(args);
109 }
110
ext2_msg(struct super_block * sb,const char * prefix,const char * fmt,...)111 void ext2_msg(struct super_block *sb, const char *prefix,
112 const char *fmt, ...)
113 {
114 struct va_format vaf;
115 va_list args;
116
117 va_start(args, fmt);
118
119 vaf.fmt = fmt;
120 vaf.va = &args;
121
122 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
123
124 va_end(args);
125 }
126
127 /*
128 * This must be called with sbi->s_lock held.
129 */
ext2_update_dynamic_rev(struct super_block * sb)130 void ext2_update_dynamic_rev(struct super_block *sb)
131 {
132 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
133
134 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
135 return;
136
137 ext2_msg(sb, KERN_WARNING,
138 "warning: updating to rev %d because of "
139 "new feature flag, running e2fsck is recommended",
140 EXT2_DYNAMIC_REV);
141
142 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
143 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
144 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
145 /* leave es->s_feature_*compat flags alone */
146 /* es->s_uuid will be set by e2fsck if empty */
147
148 /*
149 * The rest of the superblock fields should be zero, and if not it
150 * means they are likely already in use, so leave them alone. We
151 * can leave it up to e2fsck to clean up any inconsistencies there.
152 */
153 }
154
155 #ifdef CONFIG_QUOTA
156 static int ext2_quota_off(struct super_block *sb, int type);
157
ext2_quota_off_umount(struct super_block * sb)158 static void ext2_quota_off_umount(struct super_block *sb)
159 {
160 int type;
161
162 for (type = 0; type < MAXQUOTAS; type++)
163 ext2_quota_off(sb, type);
164 }
165 #else
ext2_quota_off_umount(struct super_block * sb)166 static inline void ext2_quota_off_umount(struct super_block *sb)
167 {
168 }
169 #endif
170
ext2_put_super(struct super_block * sb)171 static void ext2_put_super (struct super_block * sb)
172 {
173 int db_count;
174 int i;
175 struct ext2_sb_info *sbi = EXT2_SB(sb);
176
177 ext2_quota_off_umount(sb);
178
179 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
180 sbi->s_ea_block_cache = NULL;
181
182 if (!sb_rdonly(sb)) {
183 struct ext2_super_block *es = sbi->s_es;
184
185 spin_lock(&sbi->s_lock);
186 es->s_state = cpu_to_le16(sbi->s_mount_state);
187 spin_unlock(&sbi->s_lock);
188 ext2_sync_super(sb, es, 1);
189 }
190 db_count = sbi->s_gdb_count;
191 for (i = 0; i < db_count; i++)
192 brelse(sbi->s_group_desc[i]);
193 kvfree(sbi->s_group_desc);
194 kfree(sbi->s_debts);
195 percpu_counter_destroy(&sbi->s_freeblocks_counter);
196 percpu_counter_destroy(&sbi->s_freeinodes_counter);
197 percpu_counter_destroy(&sbi->s_dirs_counter);
198 brelse (sbi->s_sbh);
199 sb->s_fs_info = NULL;
200 kfree(sbi->s_blockgroup_lock);
201 fs_put_dax(sbi->s_daxdev, NULL);
202 kfree(sbi);
203 }
204
205 static struct kmem_cache * ext2_inode_cachep;
206
ext2_alloc_inode(struct super_block * sb)207 static struct inode *ext2_alloc_inode(struct super_block *sb)
208 {
209 struct ext2_inode_info *ei;
210 ei = alloc_inode_sb(sb, ext2_inode_cachep, GFP_KERNEL);
211 if (!ei)
212 return NULL;
213 ei->i_block_alloc_info = NULL;
214 inode_set_iversion(&ei->vfs_inode, 1);
215 #ifdef CONFIG_QUOTA
216 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
217 #endif
218
219 return &ei->vfs_inode;
220 }
221
ext2_free_in_core_inode(struct inode * inode)222 static void ext2_free_in_core_inode(struct inode *inode)
223 {
224 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
225 }
226
init_once(void * foo)227 static void init_once(void *foo)
228 {
229 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
230
231 rwlock_init(&ei->i_meta_lock);
232 #ifdef CONFIG_EXT2_FS_XATTR
233 init_rwsem(&ei->xattr_sem);
234 #endif
235 mutex_init(&ei->truncate_mutex);
236 inode_init_once(&ei->vfs_inode);
237 }
238
init_inodecache(void)239 static int __init init_inodecache(void)
240 {
241 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",
242 sizeof(struct ext2_inode_info), 0,
243 SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
244 offsetof(struct ext2_inode_info, i_data),
245 sizeof_field(struct ext2_inode_info, i_data),
246 init_once);
247 if (ext2_inode_cachep == NULL)
248 return -ENOMEM;
249 return 0;
250 }
251
destroy_inodecache(void)252 static void destroy_inodecache(void)
253 {
254 /*
255 * Make sure all delayed rcu free inodes are flushed before we
256 * destroy cache.
257 */
258 rcu_barrier();
259 kmem_cache_destroy(ext2_inode_cachep);
260 }
261
ext2_show_options(struct seq_file * seq,struct dentry * root)262 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
263 {
264 struct super_block *sb = root->d_sb;
265 struct ext2_sb_info *sbi = EXT2_SB(sb);
266 struct ext2_super_block *es = sbi->s_es;
267 unsigned long def_mount_opts;
268
269 spin_lock(&sbi->s_lock);
270 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
271
272 if (sbi->s_sb_block != 1)
273 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
274 if (test_opt(sb, MINIX_DF))
275 seq_puts(seq, ",minixdf");
276 if (test_opt(sb, GRPID))
277 seq_puts(seq, ",grpid");
278 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
279 seq_puts(seq, ",nogrpid");
280 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
281 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
282 seq_printf(seq, ",resuid=%u",
283 from_kuid_munged(&init_user_ns, sbi->s_resuid));
284 }
285 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
286 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
287 seq_printf(seq, ",resgid=%u",
288 from_kgid_munged(&init_user_ns, sbi->s_resgid));
289 }
290 if (test_opt(sb, ERRORS_RO)) {
291 int def_errors = le16_to_cpu(es->s_errors);
292
293 if (def_errors == EXT2_ERRORS_PANIC ||
294 def_errors == EXT2_ERRORS_CONTINUE) {
295 seq_puts(seq, ",errors=remount-ro");
296 }
297 }
298 if (test_opt(sb, ERRORS_CONT))
299 seq_puts(seq, ",errors=continue");
300 if (test_opt(sb, ERRORS_PANIC))
301 seq_puts(seq, ",errors=panic");
302 if (test_opt(sb, NO_UID32))
303 seq_puts(seq, ",nouid32");
304 if (test_opt(sb, DEBUG))
305 seq_puts(seq, ",debug");
306 if (test_opt(sb, OLDALLOC))
307 seq_puts(seq, ",oldalloc");
308
309 #ifdef CONFIG_EXT2_FS_XATTR
310 if (test_opt(sb, XATTR_USER))
311 seq_puts(seq, ",user_xattr");
312 if (!test_opt(sb, XATTR_USER) &&
313 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
314 seq_puts(seq, ",nouser_xattr");
315 }
316 #endif
317
318 #ifdef CONFIG_EXT2_FS_POSIX_ACL
319 if (test_opt(sb, POSIX_ACL))
320 seq_puts(seq, ",acl");
321 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
322 seq_puts(seq, ",noacl");
323 #endif
324
325 if (test_opt(sb, USRQUOTA))
326 seq_puts(seq, ",usrquota");
327
328 if (test_opt(sb, GRPQUOTA))
329 seq_puts(seq, ",grpquota");
330
331 if (test_opt(sb, XIP))
332 seq_puts(seq, ",xip");
333
334 if (test_opt(sb, DAX))
335 seq_puts(seq, ",dax");
336
337 if (!test_opt(sb, RESERVATION))
338 seq_puts(seq, ",noreservation");
339
340 spin_unlock(&sbi->s_lock);
341 return 0;
342 }
343
344 #ifdef CONFIG_QUOTA
345 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
346 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
347 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
348 const struct path *path);
ext2_get_dquots(struct inode * inode)349 static struct dquot __rcu **ext2_get_dquots(struct inode *inode)
350 {
351 return EXT2_I(inode)->i_dquot;
352 }
353
354 static const struct quotactl_ops ext2_quotactl_ops = {
355 .quota_on = ext2_quota_on,
356 .quota_off = ext2_quota_off,
357 .quota_sync = dquot_quota_sync,
358 .get_state = dquot_get_state,
359 .set_info = dquot_set_dqinfo,
360 .get_dqblk = dquot_get_dqblk,
361 .set_dqblk = dquot_set_dqblk,
362 .get_nextdqblk = dquot_get_next_dqblk,
363 };
364 #endif
365
366 static const struct super_operations ext2_sops = {
367 .alloc_inode = ext2_alloc_inode,
368 .free_inode = ext2_free_in_core_inode,
369 .write_inode = ext2_write_inode,
370 .evict_inode = ext2_evict_inode,
371 .put_super = ext2_put_super,
372 .sync_fs = ext2_sync_fs,
373 .freeze_fs = ext2_freeze,
374 .unfreeze_fs = ext2_unfreeze,
375 .statfs = ext2_statfs,
376 .show_options = ext2_show_options,
377 #ifdef CONFIG_QUOTA
378 .quota_read = ext2_quota_read,
379 .quota_write = ext2_quota_write,
380 .get_dquots = ext2_get_dquots,
381 #endif
382 };
383
ext2_nfs_get_inode(struct super_block * sb,u64 ino,u32 generation)384 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
385 u64 ino, u32 generation)
386 {
387 struct inode *inode;
388
389 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
390 return ERR_PTR(-ESTALE);
391 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
392 return ERR_PTR(-ESTALE);
393
394 /*
395 * ext2_iget isn't quite right if the inode is currently unallocated!
396 * However ext2_iget currently does appropriate checks to handle stale
397 * inodes so everything is OK.
398 */
399 inode = ext2_iget(sb, ino);
400 if (IS_ERR(inode))
401 return ERR_CAST(inode);
402 if (generation && inode->i_generation != generation) {
403 /* we didn't find the right inode.. */
404 iput(inode);
405 return ERR_PTR(-ESTALE);
406 }
407 return inode;
408 }
409
ext2_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)410 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
411 int fh_len, int fh_type)
412 {
413 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
414 ext2_nfs_get_inode);
415 }
416
ext2_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)417 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
418 int fh_len, int fh_type)
419 {
420 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
421 ext2_nfs_get_inode);
422 }
423
424 static const struct export_operations ext2_export_ops = {
425 .encode_fh = generic_encode_ino32_fh,
426 .fh_to_dentry = ext2_fh_to_dentry,
427 .fh_to_parent = ext2_fh_to_parent,
428 .get_parent = ext2_get_parent,
429 };
430
431 enum {
432 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, Opt_resgid, Opt_resuid,
433 Opt_sb, Opt_errors, Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
434 Opt_nobh, Opt_user_xattr, Opt_acl, Opt_xip, Opt_dax, Opt_ignore,
435 Opt_quota, Opt_usrquota, Opt_grpquota, Opt_reservation,
436 };
437
438 static const struct constant_table ext2_param_errors[] = {
439 {"continue", EXT2_MOUNT_ERRORS_CONT},
440 {"panic", EXT2_MOUNT_ERRORS_PANIC},
441 {"remount-ro", EXT2_MOUNT_ERRORS_RO},
442 {}
443 };
444
445 static const struct fs_parameter_spec ext2_param_spec[] = {
446 fsparam_flag ("bsddf", Opt_bsd_df),
447 fsparam_flag ("minixdf", Opt_minix_df),
448 fsparam_flag ("grpid", Opt_grpid),
449 fsparam_flag ("bsdgroups", Opt_grpid),
450 fsparam_flag ("nogrpid", Opt_nogrpid),
451 fsparam_flag ("sysvgroups", Opt_nogrpid),
452 fsparam_gid ("resgid", Opt_resgid),
453 fsparam_uid ("resuid", Opt_resuid),
454 fsparam_u32 ("sb", Opt_sb),
455 fsparam_enum ("errors", Opt_errors, ext2_param_errors),
456 fsparam_flag ("nouid32", Opt_nouid32),
457 fsparam_flag ("debug", Opt_debug),
458 fsparam_flag ("oldalloc", Opt_oldalloc),
459 fsparam_flag ("orlov", Opt_orlov),
460 fsparam_flag ("nobh", Opt_nobh),
461 fsparam_flag_no ("user_xattr", Opt_user_xattr),
462 fsparam_flag_no ("acl", Opt_acl),
463 fsparam_flag ("xip", Opt_xip),
464 fsparam_flag ("dax", Opt_dax),
465 fsparam_flag ("grpquota", Opt_grpquota),
466 fsparam_flag ("noquota", Opt_ignore),
467 fsparam_flag ("quota", Opt_quota),
468 fsparam_flag ("usrquota", Opt_usrquota),
469 fsparam_flag_no ("reservation", Opt_reservation),
470 {}
471 };
472
473 #define EXT2_SPEC_s_resuid (1 << 0)
474 #define EXT2_SPEC_s_resgid (1 << 1)
475
476 struct ext2_fs_context {
477 unsigned long vals_s_flags; /* Bits to set in s_flags */
478 unsigned long mask_s_flags; /* Bits changed in s_flags */
479 unsigned int vals_s_mount_opt;
480 unsigned int mask_s_mount_opt;
481 kuid_t s_resuid;
482 kgid_t s_resgid;
483 unsigned long s_sb_block;
484 unsigned int spec;
485
486 };
487
ctx_set_mount_opt(struct ext2_fs_context * ctx,unsigned long flag)488 static inline void ctx_set_mount_opt(struct ext2_fs_context *ctx,
489 unsigned long flag)
490 {
491 ctx->mask_s_mount_opt |= flag;
492 ctx->vals_s_mount_opt |= flag;
493 }
494
ctx_clear_mount_opt(struct ext2_fs_context * ctx,unsigned long flag)495 static inline void ctx_clear_mount_opt(struct ext2_fs_context *ctx,
496 unsigned long flag)
497 {
498 ctx->mask_s_mount_opt |= flag;
499 ctx->vals_s_mount_opt &= ~flag;
500 }
501
502 static inline unsigned long
ctx_test_mount_opt(struct ext2_fs_context * ctx,unsigned long flag)503 ctx_test_mount_opt(struct ext2_fs_context *ctx, unsigned long flag)
504 {
505 return (ctx->vals_s_mount_opt & flag);
506 }
507
508 static inline bool
ctx_parsed_mount_opt(struct ext2_fs_context * ctx,unsigned long flag)509 ctx_parsed_mount_opt(struct ext2_fs_context *ctx, unsigned long flag)
510 {
511 return (ctx->mask_s_mount_opt & flag);
512 }
513
ext2_free_fc(struct fs_context * fc)514 static void ext2_free_fc(struct fs_context *fc)
515 {
516 kfree(fc->fs_private);
517 }
518
ext2_parse_param(struct fs_context * fc,struct fs_parameter * param)519 static int ext2_parse_param(struct fs_context *fc, struct fs_parameter *param)
520 {
521 struct ext2_fs_context *ctx = fc->fs_private;
522 int opt;
523 struct fs_parse_result result;
524
525 opt = fs_parse(fc, ext2_param_spec, param, &result);
526 if (opt < 0)
527 return opt;
528
529 switch (opt) {
530 case Opt_bsd_df:
531 ctx_clear_mount_opt(ctx, EXT2_MOUNT_MINIX_DF);
532 break;
533 case Opt_minix_df:
534 ctx_set_mount_opt(ctx, EXT2_MOUNT_MINIX_DF);
535 break;
536 case Opt_grpid:
537 ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPID);
538 break;
539 case Opt_nogrpid:
540 ctx_clear_mount_opt(ctx, EXT2_MOUNT_GRPID);
541 break;
542 case Opt_resuid:
543 ctx->s_resuid = result.uid;
544 ctx->spec |= EXT2_SPEC_s_resuid;
545 break;
546 case Opt_resgid:
547 ctx->s_resgid = result.gid;
548 ctx->spec |= EXT2_SPEC_s_resgid;
549 break;
550 case Opt_sb:
551 /* Note that this is silently ignored on remount */
552 ctx->s_sb_block = result.uint_32;
553 break;
554 case Opt_errors:
555 ctx_clear_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK);
556 ctx_set_mount_opt(ctx, result.uint_32);
557 break;
558 case Opt_nouid32:
559 ctx_set_mount_opt(ctx, EXT2_MOUNT_NO_UID32);
560 break;
561 case Opt_debug:
562 ctx_set_mount_opt(ctx, EXT2_MOUNT_DEBUG);
563 break;
564 case Opt_oldalloc:
565 ctx_set_mount_opt(ctx, EXT2_MOUNT_OLDALLOC);
566 break;
567 case Opt_orlov:
568 ctx_clear_mount_opt(ctx, EXT2_MOUNT_OLDALLOC);
569 break;
570 case Opt_nobh:
571 ext2_msg_fc(fc, KERN_INFO, "nobh option not supported\n");
572 break;
573 #ifdef CONFIG_EXT2_FS_XATTR
574 case Opt_user_xattr:
575 if (!result.negated)
576 ctx_set_mount_opt(ctx, EXT2_MOUNT_XATTR_USER);
577 else
578 ctx_clear_mount_opt(ctx, EXT2_MOUNT_XATTR_USER);
579 break;
580 #else
581 case Opt_user_xattr:
582 ext2_msg_fc(fc, KERN_INFO, "(no)user_xattr options not supported");
583 break;
584 #endif
585 #ifdef CONFIG_EXT2_FS_POSIX_ACL
586 case Opt_acl:
587 if (!result.negated)
588 ctx_set_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL);
589 else
590 ctx_clear_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL);
591 break;
592 #else
593 case Opt_acl:
594 ext2_msg_fc(fc, KERN_INFO, "(no)acl options not supported");
595 break;
596 #endif
597 case Opt_xip:
598 ext2_msg_fc(fc, KERN_INFO, "use dax instead of xip");
599 ctx_set_mount_opt(ctx, EXT2_MOUNT_XIP);
600 fallthrough;
601 case Opt_dax:
602 #ifdef CONFIG_FS_DAX
603 ext2_msg_fc(fc, KERN_WARNING,
604 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
605 ctx_set_mount_opt(ctx, EXT2_MOUNT_DAX);
606 #else
607 ext2_msg_fc(fc, KERN_INFO, "dax option not supported");
608 #endif
609 break;
610
611 #if defined(CONFIG_QUOTA)
612 case Opt_quota:
613 case Opt_usrquota:
614 ctx_set_mount_opt(ctx, EXT2_MOUNT_USRQUOTA);
615 break;
616
617 case Opt_grpquota:
618 ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPQUOTA);
619 break;
620 #else
621 case Opt_quota:
622 case Opt_usrquota:
623 case Opt_grpquota:
624 ext2_msg_fc(fc, KERN_INFO, "quota operations not supported");
625 break;
626 #endif
627 case Opt_reservation:
628 if (!result.negated) {
629 ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
630 ext2_msg_fc(fc, KERN_INFO, "reservations ON");
631 } else {
632 ctx_clear_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
633 ext2_msg_fc(fc, KERN_INFO, "reservations OFF");
634 }
635 break;
636 case Opt_ignore:
637 break;
638 default:
639 return -EINVAL;
640 }
641 return 0;
642 }
643
ext2_setup_super(struct super_block * sb,struct ext2_super_block * es,int read_only)644 static int ext2_setup_super (struct super_block * sb,
645 struct ext2_super_block * es,
646 int read_only)
647 {
648 int res = 0;
649 struct ext2_sb_info *sbi = EXT2_SB(sb);
650
651 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
652 ext2_msg(sb, KERN_ERR,
653 "error: revision level too high, "
654 "forcing read-only mode");
655 res = SB_RDONLY;
656 }
657 if (read_only)
658 return res;
659 if (!(sbi->s_mount_state & EXT2_VALID_FS))
660 ext2_msg(sb, KERN_WARNING,
661 "warning: mounting unchecked fs, "
662 "running e2fsck is recommended");
663 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
664 ext2_msg(sb, KERN_WARNING,
665 "warning: mounting fs with errors, "
666 "running e2fsck is recommended");
667 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
668 le16_to_cpu(es->s_mnt_count) >=
669 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
670 ext2_msg(sb, KERN_WARNING,
671 "warning: maximal mount count reached, "
672 "running e2fsck is recommended");
673 else if (le32_to_cpu(es->s_checkinterval) &&
674 (le32_to_cpu(es->s_lastcheck) +
675 le32_to_cpu(es->s_checkinterval) <=
676 ktime_get_real_seconds()))
677 ext2_msg(sb, KERN_WARNING,
678 "warning: checktime reached, "
679 "running e2fsck is recommended");
680 if (!le16_to_cpu(es->s_max_mnt_count))
681 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
682 le16_add_cpu(&es->s_mnt_count, 1);
683 if (test_opt (sb, DEBUG))
684 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, "
685 "bpg=%lu, ipg=%lu, mo=%04lx]",
686 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
687 sbi->s_groups_count,
688 EXT2_BLOCKS_PER_GROUP(sb),
689 EXT2_INODES_PER_GROUP(sb),
690 sbi->s_mount_opt);
691 return res;
692 }
693
ext2_check_descriptors(struct super_block * sb)694 static int ext2_check_descriptors(struct super_block *sb)
695 {
696 int i;
697 struct ext2_sb_info *sbi = EXT2_SB(sb);
698
699 ext2_debug ("Checking group descriptors");
700
701 for (i = 0; i < sbi->s_groups_count; i++) {
702 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
703 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
704 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i);
705
706 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
707 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
708 {
709 ext2_error (sb, "ext2_check_descriptors",
710 "Block bitmap for group %d"
711 " not in group (block %lu)!",
712 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
713 return 0;
714 }
715 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
716 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
717 {
718 ext2_error (sb, "ext2_check_descriptors",
719 "Inode bitmap for group %d"
720 " not in group (block %lu)!",
721 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
722 return 0;
723 }
724 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
725 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
726 last_block)
727 {
728 ext2_error (sb, "ext2_check_descriptors",
729 "Inode table for group %d"
730 " not in group (block %lu)!",
731 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
732 return 0;
733 }
734 }
735 return 1;
736 }
737
738 /*
739 * Maximal file size. There is a direct, and {,double-,triple-}indirect
740 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
741 * We need to be 1 filesystem block less than the 2^32 sector limit.
742 */
ext2_max_size(int bits)743 static loff_t ext2_max_size(int bits)
744 {
745 loff_t res = EXT2_NDIR_BLOCKS;
746 int meta_blocks;
747 unsigned int upper_limit;
748 unsigned int ppb = 1 << (bits-2);
749
750 /* This is calculated to be the largest file size for a
751 * dense, file such that the total number of
752 * sectors in the file, including data and all indirect blocks,
753 * does not exceed 2^32 -1
754 * __u32 i_blocks representing the total number of
755 * 512 bytes blocks of the file
756 */
757 upper_limit = (1LL << 32) - 1;
758
759 /* total blocks in file system block size */
760 upper_limit >>= (bits - 9);
761
762 /* Compute how many blocks we can address by block tree */
763 res += 1LL << (bits-2);
764 res += 1LL << (2*(bits-2));
765 res += 1LL << (3*(bits-2));
766 /* Compute how many metadata blocks are needed */
767 meta_blocks = 1;
768 meta_blocks += 1 + ppb;
769 meta_blocks += 1 + ppb + ppb * ppb;
770 /* Does block tree limit file size? */
771 if (res + meta_blocks <= upper_limit)
772 goto check_lfs;
773
774 res = upper_limit;
775 /* How many metadata blocks are needed for addressing upper_limit? */
776 upper_limit -= EXT2_NDIR_BLOCKS;
777 /* indirect blocks */
778 meta_blocks = 1;
779 upper_limit -= ppb;
780 /* double indirect blocks */
781 if (upper_limit < ppb * ppb) {
782 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
783 res -= meta_blocks;
784 goto check_lfs;
785 }
786 meta_blocks += 1 + ppb;
787 upper_limit -= ppb * ppb;
788 /* tripple indirect blocks for the rest */
789 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
790 DIV_ROUND_UP(upper_limit, ppb*ppb);
791 res -= meta_blocks;
792 check_lfs:
793 res <<= bits;
794 if (res > MAX_LFS_FILESIZE)
795 res = MAX_LFS_FILESIZE;
796
797 return res;
798 }
799
descriptor_loc(struct super_block * sb,unsigned long logic_sb_block,int nr)800 static unsigned long descriptor_loc(struct super_block *sb,
801 unsigned long logic_sb_block,
802 int nr)
803 {
804 struct ext2_sb_info *sbi = EXT2_SB(sb);
805 unsigned long bg, first_meta_bg;
806
807 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
808
809 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
810 nr < first_meta_bg)
811 return (logic_sb_block + nr + 1);
812 bg = sbi->s_desc_per_block * nr;
813
814 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);
815 }
816
817 /*
818 * Set all mount options either from defaults on disk, or from parsed
819 * options. Parsed/specified options override on-disk defaults.
820 */
ext2_set_options(struct fs_context * fc,struct ext2_sb_info * sbi)821 static void ext2_set_options(struct fs_context *fc, struct ext2_sb_info *sbi)
822 {
823 struct ext2_fs_context *ctx = fc->fs_private;
824 struct ext2_super_block *es = sbi->s_es;
825 unsigned long def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
826
827 /* Copy parsed mount options to sbi */
828 sbi->s_mount_opt = ctx->vals_s_mount_opt;
829
830 /* Use in-superblock defaults only if not specified during parsing */
831 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_DEBUG) &&
832 def_mount_opts & EXT2_DEFM_DEBUG)
833 set_opt(sbi->s_mount_opt, DEBUG);
834
835 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_GRPID) &&
836 def_mount_opts & EXT2_DEFM_BSDGROUPS)
837 set_opt(sbi->s_mount_opt, GRPID);
838
839 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_NO_UID32) &&
840 def_mount_opts & EXT2_DEFM_UID16)
841 set_opt(sbi->s_mount_opt, NO_UID32);
842
843 #ifdef CONFIG_EXT2_FS_XATTR
844 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_XATTR_USER) &&
845 def_mount_opts & EXT2_DEFM_XATTR_USER)
846 set_opt(sbi->s_mount_opt, XATTR_USER);
847 #endif
848 #ifdef CONFIG_EXT2_FS_POSIX_ACL
849 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL) &&
850 def_mount_opts & EXT2_DEFM_ACL)
851 set_opt(sbi->s_mount_opt, POSIX_ACL);
852 #endif
853
854 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK)) {
855 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
856 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
857 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
858 set_opt(sbi->s_mount_opt, ERRORS_CONT);
859 else
860 set_opt(sbi->s_mount_opt, ERRORS_RO);
861 }
862
863 if (ctx->spec & EXT2_SPEC_s_resuid)
864 sbi->s_resuid = ctx->s_resuid;
865 else
866 sbi->s_resuid = make_kuid(&init_user_ns,
867 le16_to_cpu(es->s_def_resuid));
868
869 if (ctx->spec & EXT2_SPEC_s_resgid)
870 sbi->s_resgid = ctx->s_resgid;
871 else
872 sbi->s_resgid = make_kgid(&init_user_ns,
873 le16_to_cpu(es->s_def_resgid));
874 }
875
ext2_fill_super(struct super_block * sb,struct fs_context * fc)876 static int ext2_fill_super(struct super_block *sb, struct fs_context *fc)
877 {
878 struct ext2_fs_context *ctx = fc->fs_private;
879 int silent = fc->sb_flags & SB_SILENT;
880 struct buffer_head * bh;
881 struct ext2_sb_info * sbi;
882 struct ext2_super_block * es;
883 struct inode *root;
884 unsigned long block;
885 unsigned long sb_block = ctx->s_sb_block;
886 unsigned long logic_sb_block;
887 unsigned long offset = 0;
888 long ret = -ENOMEM;
889 int blocksize = BLOCK_SIZE;
890 int db_count;
891 int i, j;
892 __le32 features;
893 int err;
894
895 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
896 if (!sbi)
897 return -ENOMEM;
898
899 sbi->s_blockgroup_lock =
900 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
901 if (!sbi->s_blockgroup_lock) {
902 kfree(sbi);
903 return -ENOMEM;
904 }
905 sb->s_fs_info = sbi;
906 sbi->s_sb_block = sb_block;
907 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
908 NULL, NULL);
909
910 spin_lock_init(&sbi->s_lock);
911 ret = -EINVAL;
912
913 /*
914 * See what the current blocksize for the device is, and
915 * use that as the blocksize. Otherwise (or if the blocksize
916 * is smaller than the default) use the default.
917 * This is important for devices that have a hardware
918 * sectorsize that is larger than the default.
919 */
920 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
921 if (!blocksize) {
922 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
923 goto failed_sbi;
924 }
925
926 /*
927 * If the superblock doesn't start on a hardware sector boundary,
928 * calculate the offset.
929 */
930 if (blocksize != BLOCK_SIZE) {
931 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
932 offset = (sb_block*BLOCK_SIZE) % blocksize;
933 } else {
934 logic_sb_block = sb_block;
935 }
936
937 if (!(bh = sb_bread(sb, logic_sb_block))) {
938 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
939 goto failed_sbi;
940 }
941 /*
942 * Note: s_es must be initialized as soon as possible because
943 * some ext2 macro-instructions depend on its value
944 */
945 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
946 sbi->s_es = es;
947 sb->s_magic = le16_to_cpu(es->s_magic);
948
949 if (sb->s_magic != EXT2_SUPER_MAGIC)
950 goto cantfind_ext2;
951
952 ext2_set_options(fc, sbi);
953
954 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
955 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
956 sb->s_iflags |= SB_I_CGROUPWB;
957
958 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
959 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
960 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
961 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
962 ext2_msg(sb, KERN_WARNING,
963 "warning: feature flags set on rev 0 fs, "
964 "running e2fsck is recommended");
965 /*
966 * Check feature flags regardless of the revision level, since we
967 * previously didn't change the revision level when setting the flags,
968 * so there is a chance incompat flags are set on a rev 0 filesystem.
969 */
970 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
971 if (features) {
972 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
973 "unsupported optional features (%x)",
974 le32_to_cpu(features));
975 goto failed_mount;
976 }
977 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
978 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
979 "unsupported optional features (%x)",
980 le32_to_cpu(features));
981 goto failed_mount;
982 }
983
984 if (le32_to_cpu(es->s_log_block_size) >
985 (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) {
986 ext2_msg(sb, KERN_ERR,
987 "Invalid log block size: %u",
988 le32_to_cpu(es->s_log_block_size));
989 goto failed_mount;
990 }
991 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
992
993 if (test_opt(sb, DAX)) {
994 if (!sbi->s_daxdev) {
995 ext2_msg(sb, KERN_ERR,
996 "DAX unsupported by block device. Turning off DAX.");
997 clear_opt(sbi->s_mount_opt, DAX);
998 } else if (blocksize != PAGE_SIZE) {
999 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
1000 clear_opt(sbi->s_mount_opt, DAX);
1001 }
1002 }
1003
1004 /* If the blocksize doesn't match, re-read the thing.. */
1005 if (sb->s_blocksize != blocksize) {
1006 brelse(bh);
1007
1008 if (!sb_set_blocksize(sb, blocksize)) {
1009 ext2_msg(sb, KERN_ERR,
1010 "error: bad blocksize %d", blocksize);
1011 goto failed_sbi;
1012 }
1013
1014 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
1015 offset = (sb_block*BLOCK_SIZE) % blocksize;
1016 bh = sb_bread(sb, logic_sb_block);
1017 if(!bh) {
1018 ext2_msg(sb, KERN_ERR, "error: couldn't read"
1019 "superblock on 2nd try");
1020 goto failed_sbi;
1021 }
1022 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
1023 sbi->s_es = es;
1024 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
1025 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
1026 goto failed_mount;
1027 }
1028 }
1029
1030 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
1031 sb->s_max_links = EXT2_LINK_MAX;
1032 sb->s_time_min = S32_MIN;
1033 sb->s_time_max = S32_MAX;
1034
1035 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
1036 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
1037 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
1038 } else {
1039 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1040 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1041 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1042 !is_power_of_2(sbi->s_inode_size) ||
1043 (sbi->s_inode_size > blocksize)) {
1044 ext2_msg(sb, KERN_ERR,
1045 "error: unsupported inode size: %d",
1046 sbi->s_inode_size);
1047 goto failed_mount;
1048 }
1049 }
1050
1051 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1052 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1053
1054 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1055 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1056 goto cantfind_ext2;
1057 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1058 sbi->s_inodes_per_block;
1059 sbi->s_desc_per_block = sb->s_blocksize /
1060 sizeof (struct ext2_group_desc);
1061 sbi->s_sbh = bh;
1062 sbi->s_mount_state = le16_to_cpu(es->s_state);
1063 sbi->s_addr_per_block_bits =
1064 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1065 sbi->s_desc_per_block_bits =
1066 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1067
1068 if (sb->s_magic != EXT2_SUPER_MAGIC)
1069 goto cantfind_ext2;
1070
1071 if (sb->s_blocksize != bh->b_size) {
1072 if (!silent)
1073 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1074 goto failed_mount;
1075 }
1076
1077 if (es->s_log_frag_size != es->s_log_block_size) {
1078 ext2_msg(sb, KERN_ERR,
1079 "error: fragsize log %u != blocksize log %u",
1080 le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits);
1081 goto failed_mount;
1082 }
1083
1084 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1085 ext2_msg(sb, KERN_ERR,
1086 "error: #blocks per group too big: %lu",
1087 sbi->s_blocks_per_group);
1088 goto failed_mount;
1089 }
1090 /* At least inode table, bitmaps, and sb have to fit in one group */
1091 if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) {
1092 ext2_msg(sb, KERN_ERR,
1093 "error: #blocks per group smaller than metadata size: %lu <= %lu",
1094 sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3);
1095 goto failed_mount;
1096 }
1097 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
1098 sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1099 ext2_msg(sb, KERN_ERR,
1100 "error: invalid #inodes per group: %lu",
1101 sbi->s_inodes_per_group);
1102 goto failed_mount;
1103 }
1104 if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) {
1105 ext2_msg(sb, KERN_ERR,
1106 "bad geometry: block count %u exceeds size of device (%u blocks)",
1107 le32_to_cpu(es->s_blocks_count),
1108 (unsigned)sb_bdev_nr_blocks(sb));
1109 goto failed_mount;
1110 }
1111
1112 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1113 le32_to_cpu(es->s_first_data_block) - 1)
1114 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1115 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=
1116 le32_to_cpu(es->s_inodes_count)) {
1117 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",
1118 le32_to_cpu(es->s_inodes_count),
1119 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);
1120 goto failed_mount;
1121 }
1122 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1123 EXT2_DESC_PER_BLOCK(sb);
1124 sbi->s_group_desc = kvmalloc_array(db_count,
1125 sizeof(struct buffer_head *),
1126 GFP_KERNEL);
1127 if (sbi->s_group_desc == NULL) {
1128 ret = -ENOMEM;
1129 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1130 goto failed_mount;
1131 }
1132 bgl_lock_init(sbi->s_blockgroup_lock);
1133 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1134 if (!sbi->s_debts) {
1135 ret = -ENOMEM;
1136 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1137 goto failed_mount_group_desc;
1138 }
1139 for (i = 0; i < db_count; i++) {
1140 block = descriptor_loc(sb, logic_sb_block, i);
1141 sbi->s_group_desc[i] = sb_bread(sb, block);
1142 if (!sbi->s_group_desc[i]) {
1143 for (j = 0; j < i; j++)
1144 brelse (sbi->s_group_desc[j]);
1145 ext2_msg(sb, KERN_ERR,
1146 "error: unable to read group descriptors");
1147 goto failed_mount_group_desc;
1148 }
1149 }
1150 if (!ext2_check_descriptors (sb)) {
1151 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1152 goto failed_mount2;
1153 }
1154 sbi->s_gdb_count = db_count;
1155 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1156 spin_lock_init(&sbi->s_next_gen_lock);
1157
1158 /* per filesystem reservation list head & lock */
1159 spin_lock_init(&sbi->s_rsv_window_lock);
1160 sbi->s_rsv_window_root = RB_ROOT;
1161 /*
1162 * Add a single, static dummy reservation to the start of the
1163 * reservation window list --- it gives us a placeholder for
1164 * append-at-start-of-list which makes the allocation logic
1165 * _much_ simpler.
1166 */
1167 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1168 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1169 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1170 sbi->s_rsv_window_head.rsv_goal_size = 0;
1171 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1172
1173 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1174 ext2_count_free_blocks(sb), GFP_KERNEL);
1175 if (!err) {
1176 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1177 ext2_count_free_inodes(sb), GFP_KERNEL);
1178 }
1179 if (!err) {
1180 err = percpu_counter_init(&sbi->s_dirs_counter,
1181 ext2_count_dirs(sb), GFP_KERNEL);
1182 }
1183 if (err) {
1184 ret = err;
1185 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1186 goto failed_mount3;
1187 }
1188
1189 #ifdef CONFIG_EXT2_FS_XATTR
1190 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1191 if (!sbi->s_ea_block_cache) {
1192 ret = -ENOMEM;
1193 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1194 goto failed_mount3;
1195 }
1196 #endif
1197 /*
1198 * set up enough so that it can read an inode
1199 */
1200 sb->s_op = &ext2_sops;
1201 sb->s_export_op = &ext2_export_ops;
1202 sb->s_xattr = ext2_xattr_handlers;
1203
1204 #ifdef CONFIG_QUOTA
1205 sb->dq_op = &dquot_operations;
1206 sb->s_qcop = &ext2_quotactl_ops;
1207 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1208 #endif
1209
1210 root = ext2_iget(sb, EXT2_ROOT_INO);
1211 if (IS_ERR(root)) {
1212 ret = PTR_ERR(root);
1213 goto failed_mount3;
1214 }
1215 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1216 iput(root);
1217 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1218 goto failed_mount3;
1219 }
1220
1221 sb->s_root = d_make_root(root);
1222 if (!sb->s_root) {
1223 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1224 ret = -ENOMEM;
1225 goto failed_mount3;
1226 }
1227 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1228 ext2_msg(sb, KERN_WARNING,
1229 "warning: mounting ext3 filesystem as ext2");
1230 if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1231 sb->s_flags |= SB_RDONLY;
1232 ext2_write_super(sb);
1233 return 0;
1234
1235 cantfind_ext2:
1236 if (!silent)
1237 ext2_msg(sb, KERN_ERR,
1238 "error: can't find an ext2 filesystem on dev %s.",
1239 sb->s_id);
1240 goto failed_mount;
1241 failed_mount3:
1242 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1243 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1244 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1245 percpu_counter_destroy(&sbi->s_dirs_counter);
1246 failed_mount2:
1247 for (i = 0; i < db_count; i++)
1248 brelse(sbi->s_group_desc[i]);
1249 failed_mount_group_desc:
1250 kvfree(sbi->s_group_desc);
1251 kfree(sbi->s_debts);
1252 failed_mount:
1253 brelse(bh);
1254 failed_sbi:
1255 fs_put_dax(sbi->s_daxdev, NULL);
1256 sb->s_fs_info = NULL;
1257 kfree(sbi->s_blockgroup_lock);
1258 kfree(sbi);
1259 return ret;
1260 }
1261
ext2_clear_super_error(struct super_block * sb)1262 static void ext2_clear_super_error(struct super_block *sb)
1263 {
1264 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1265
1266 if (buffer_write_io_error(sbh)) {
1267 /*
1268 * Oh, dear. A previous attempt to write the
1269 * superblock failed. This could happen because the
1270 * USB device was yanked out. Or it could happen to
1271 * be a transient write error and maybe the block will
1272 * be remapped. Nothing we can do but to retry the
1273 * write and hope for the best.
1274 */
1275 ext2_msg(sb, KERN_ERR,
1276 "previous I/O error to superblock detected");
1277 clear_buffer_write_io_error(sbh);
1278 set_buffer_uptodate(sbh);
1279 }
1280 }
1281
ext2_sync_super(struct super_block * sb,struct ext2_super_block * es,int wait)1282 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1283 int wait)
1284 {
1285 ext2_clear_super_error(sb);
1286 spin_lock(&EXT2_SB(sb)->s_lock);
1287 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1288 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1289 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1290 /* unlock before we do IO */
1291 spin_unlock(&EXT2_SB(sb)->s_lock);
1292 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1293 if (wait)
1294 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1295 }
1296
1297 /*
1298 * In the second extended file system, it is not necessary to
1299 * write the super block since we use a mapping of the
1300 * disk super block in a buffer.
1301 *
1302 * However, this function is still used to set the fs valid
1303 * flags to 0. We need to set this flag to 0 since the fs
1304 * may have been checked while mounted and e2fsck may have
1305 * set s_state to EXT2_VALID_FS after some corrections.
1306 */
ext2_sync_fs(struct super_block * sb,int wait)1307 static int ext2_sync_fs(struct super_block *sb, int wait)
1308 {
1309 struct ext2_sb_info *sbi = EXT2_SB(sb);
1310 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1311
1312 /*
1313 * Write quota structures to quota file, sync_blockdev() will write
1314 * them to disk later
1315 */
1316 dquot_writeback_dquots(sb, -1);
1317
1318 spin_lock(&sbi->s_lock);
1319 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1320 ext2_debug("setting valid to 0\n");
1321 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1322 }
1323 spin_unlock(&sbi->s_lock);
1324 ext2_sync_super(sb, es, wait);
1325 return 0;
1326 }
1327
ext2_freeze(struct super_block * sb)1328 static int ext2_freeze(struct super_block *sb)
1329 {
1330 struct ext2_sb_info *sbi = EXT2_SB(sb);
1331
1332 /*
1333 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1334 * because we have unattached inodes and thus filesystem is not fully
1335 * consistent.
1336 */
1337 if (atomic_long_read(&sb->s_remove_count)) {
1338 ext2_sync_fs(sb, 1);
1339 return 0;
1340 }
1341 /* Set EXT2_FS_VALID flag */
1342 spin_lock(&sbi->s_lock);
1343 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1344 spin_unlock(&sbi->s_lock);
1345 ext2_sync_super(sb, sbi->s_es, 1);
1346
1347 return 0;
1348 }
1349
ext2_unfreeze(struct super_block * sb)1350 static int ext2_unfreeze(struct super_block *sb)
1351 {
1352 /* Just write sb to clear EXT2_VALID_FS flag */
1353 ext2_write_super(sb);
1354
1355 return 0;
1356 }
1357
ext2_write_super(struct super_block * sb)1358 static void ext2_write_super(struct super_block *sb)
1359 {
1360 if (!sb_rdonly(sb))
1361 ext2_sync_fs(sb, 1);
1362 }
1363
ext2_reconfigure(struct fs_context * fc)1364 static int ext2_reconfigure(struct fs_context *fc)
1365 {
1366 struct ext2_fs_context *ctx = fc->fs_private;
1367 struct super_block *sb = fc->root->d_sb;
1368 struct ext2_sb_info * sbi = EXT2_SB(sb);
1369 struct ext2_super_block * es;
1370 struct ext2_mount_options new_opts;
1371 int flags = fc->sb_flags;
1372 int err;
1373
1374 sync_filesystem(sb);
1375
1376 new_opts.s_mount_opt = ctx->vals_s_mount_opt;
1377 new_opts.s_resuid = ctx->s_resuid;
1378 new_opts.s_resgid = ctx->s_resgid;
1379
1380 spin_lock(&sbi->s_lock);
1381 es = sbi->s_es;
1382 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1383 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1384 "dax flag with busy inodes while remounting");
1385 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1386 }
1387 if ((bool)(flags & SB_RDONLY) == sb_rdonly(sb))
1388 goto out_set;
1389 if (flags & SB_RDONLY) {
1390 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1391 !(sbi->s_mount_state & EXT2_VALID_FS))
1392 goto out_set;
1393
1394 /*
1395 * OK, we are remounting a valid rw partition rdonly, so set
1396 * the rdonly flag and then mark the partition as valid again.
1397 */
1398 es->s_state = cpu_to_le16(sbi->s_mount_state);
1399 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1400 spin_unlock(&sbi->s_lock);
1401
1402 err = dquot_suspend(sb, -1);
1403 if (err < 0)
1404 return err;
1405
1406 ext2_sync_super(sb, es, 1);
1407 } else {
1408 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1409 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1410 if (ret) {
1411 spin_unlock(&sbi->s_lock);
1412 ext2_msg(sb, KERN_WARNING,
1413 "warning: couldn't remount RDWR because of "
1414 "unsupported optional features (%x).",
1415 le32_to_cpu(ret));
1416 return -EROFS;
1417 }
1418 /*
1419 * Mounting a RDONLY partition read-write, so reread and
1420 * store the current valid flag. (It may have been changed
1421 * by e2fsck since we originally mounted the partition.)
1422 */
1423 sbi->s_mount_state = le16_to_cpu(es->s_state);
1424 if (!ext2_setup_super (sb, es, 0))
1425 sb->s_flags &= ~SB_RDONLY;
1426 spin_unlock(&sbi->s_lock);
1427
1428 ext2_write_super(sb);
1429
1430 dquot_resume(sb, -1);
1431 }
1432
1433 spin_lock(&sbi->s_lock);
1434 out_set:
1435 sbi->s_mount_opt = new_opts.s_mount_opt;
1436 sbi->s_resuid = new_opts.s_resuid;
1437 sbi->s_resgid = new_opts.s_resgid;
1438 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1439 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
1440 spin_unlock(&sbi->s_lock);
1441
1442 return 0;
1443 }
1444
ext2_statfs(struct dentry * dentry,struct kstatfs * buf)1445 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1446 {
1447 struct super_block *sb = dentry->d_sb;
1448 struct ext2_sb_info *sbi = EXT2_SB(sb);
1449 struct ext2_super_block *es = sbi->s_es;
1450
1451 spin_lock(&sbi->s_lock);
1452
1453 if (test_opt (sb, MINIX_DF))
1454 sbi->s_overhead_last = 0;
1455 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1456 unsigned long i, overhead = 0;
1457 smp_rmb();
1458
1459 /*
1460 * Compute the overhead (FS structures). This is constant
1461 * for a given filesystem unless the number of block groups
1462 * changes so we cache the previous value until it does.
1463 */
1464
1465 /*
1466 * All of the blocks before first_data_block are
1467 * overhead
1468 */
1469 overhead = le32_to_cpu(es->s_first_data_block);
1470
1471 /*
1472 * Add the overhead attributed to the superblock and
1473 * block group descriptors. If the sparse superblocks
1474 * feature is turned on, then not all groups have this.
1475 */
1476 for (i = 0; i < sbi->s_groups_count; i++)
1477 overhead += ext2_bg_has_super(sb, i) +
1478 ext2_bg_num_gdb(sb, i);
1479
1480 /*
1481 * Every block group has an inode bitmap, a block
1482 * bitmap, and an inode table.
1483 */
1484 overhead += (sbi->s_groups_count *
1485 (2 + sbi->s_itb_per_group));
1486 sbi->s_overhead_last = overhead;
1487 smp_wmb();
1488 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1489 }
1490
1491 buf->f_type = EXT2_SUPER_MAGIC;
1492 buf->f_bsize = sb->s_blocksize;
1493 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1494 buf->f_bfree = ext2_count_free_blocks(sb);
1495 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1496 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1497 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1498 buf->f_bavail = 0;
1499 buf->f_files = le32_to_cpu(es->s_inodes_count);
1500 buf->f_ffree = ext2_count_free_inodes(sb);
1501 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1502 buf->f_namelen = EXT2_NAME_LEN;
1503 buf->f_fsid = uuid_to_fsid(es->s_uuid);
1504 spin_unlock(&sbi->s_lock);
1505 return 0;
1506 }
1507
ext2_get_tree(struct fs_context * fc)1508 static int ext2_get_tree(struct fs_context *fc)
1509 {
1510 return get_tree_bdev(fc, ext2_fill_super);
1511 }
1512
1513 #ifdef CONFIG_QUOTA
1514
1515 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1516 * acquiring the locks... As quota files are never truncated and quota code
1517 * itself serializes the operations (and no one else should touch the files)
1518 * we don't have to be afraid of races */
ext2_quota_read(struct super_block * sb,int type,char * data,size_t len,loff_t off)1519 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1520 size_t len, loff_t off)
1521 {
1522 struct inode *inode = sb_dqopt(sb)->files[type];
1523 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1524 int err = 0;
1525 int offset = off & (sb->s_blocksize - 1);
1526 int tocopy;
1527 size_t toread;
1528 struct buffer_head tmp_bh;
1529 struct buffer_head *bh;
1530 loff_t i_size = i_size_read(inode);
1531
1532 if (off > i_size)
1533 return 0;
1534 if (off+len > i_size)
1535 len = i_size-off;
1536 toread = len;
1537 while (toread > 0) {
1538 tocopy = min_t(size_t, sb->s_blocksize - offset, toread);
1539
1540 tmp_bh.b_state = 0;
1541 tmp_bh.b_size = sb->s_blocksize;
1542 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1543 if (err < 0)
1544 return err;
1545 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1546 memset(data, 0, tocopy);
1547 else {
1548 bh = sb_bread(sb, tmp_bh.b_blocknr);
1549 if (!bh)
1550 return -EIO;
1551 memcpy(data, bh->b_data+offset, tocopy);
1552 brelse(bh);
1553 }
1554 offset = 0;
1555 toread -= tocopy;
1556 data += tocopy;
1557 blk++;
1558 }
1559 return len;
1560 }
1561
1562 /* Write to quotafile */
ext2_quota_write(struct super_block * sb,int type,const char * data,size_t len,loff_t off)1563 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1564 const char *data, size_t len, loff_t off)
1565 {
1566 struct inode *inode = sb_dqopt(sb)->files[type];
1567 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1568 int err = 0;
1569 int offset = off & (sb->s_blocksize - 1);
1570 int tocopy;
1571 size_t towrite = len;
1572 struct buffer_head tmp_bh;
1573 struct buffer_head *bh;
1574
1575 while (towrite > 0) {
1576 tocopy = min_t(size_t, sb->s_blocksize - offset, towrite);
1577
1578 tmp_bh.b_state = 0;
1579 tmp_bh.b_size = sb->s_blocksize;
1580 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1581 if (err < 0)
1582 goto out;
1583 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1584 bh = sb_bread(sb, tmp_bh.b_blocknr);
1585 else
1586 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1587 if (unlikely(!bh)) {
1588 err = -EIO;
1589 goto out;
1590 }
1591 lock_buffer(bh);
1592 memcpy(bh->b_data+offset, data, tocopy);
1593 flush_dcache_folio(bh->b_folio);
1594 set_buffer_uptodate(bh);
1595 mark_buffer_dirty(bh);
1596 unlock_buffer(bh);
1597 brelse(bh);
1598 offset = 0;
1599 towrite -= tocopy;
1600 data += tocopy;
1601 blk++;
1602 }
1603 out:
1604 if (len == towrite)
1605 return err;
1606 if (inode->i_size < off+len-towrite)
1607 i_size_write(inode, off+len-towrite);
1608 inode_inc_iversion(inode);
1609 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1610 mark_inode_dirty(inode);
1611 return len - towrite;
1612 }
1613
ext2_quota_on(struct super_block * sb,int type,int format_id,const struct path * path)1614 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1615 const struct path *path)
1616 {
1617 int err;
1618 struct inode *inode;
1619
1620 err = dquot_quota_on(sb, type, format_id, path);
1621 if (err)
1622 return err;
1623
1624 inode = d_inode(path->dentry);
1625 inode_lock(inode);
1626 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1627 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1628 S_NOATIME | S_IMMUTABLE);
1629 inode_unlock(inode);
1630 mark_inode_dirty(inode);
1631
1632 return 0;
1633 }
1634
ext2_quota_off(struct super_block * sb,int type)1635 static int ext2_quota_off(struct super_block *sb, int type)
1636 {
1637 struct inode *inode = sb_dqopt(sb)->files[type];
1638 int err;
1639
1640 if (!inode || !igrab(inode))
1641 goto out;
1642
1643 err = dquot_quota_off(sb, type);
1644 if (err)
1645 goto out_put;
1646
1647 inode_lock(inode);
1648 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1649 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1650 inode_unlock(inode);
1651 mark_inode_dirty(inode);
1652 out_put:
1653 iput(inode);
1654 return err;
1655 out:
1656 return dquot_quota_off(sb, type);
1657 }
1658
1659 #endif
1660
1661 static const struct fs_context_operations ext2_context_ops = {
1662 .parse_param = ext2_parse_param,
1663 .get_tree = ext2_get_tree,
1664 .reconfigure = ext2_reconfigure,
1665 .free = ext2_free_fc,
1666 };
1667
ext2_init_fs_context(struct fs_context * fc)1668 static int ext2_init_fs_context(struct fs_context *fc)
1669 {
1670 struct ext2_fs_context *ctx;
1671
1672 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1673 if (!ctx)
1674 return -ENOMEM;
1675
1676 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
1677 struct super_block *sb = fc->root->d_sb;
1678 struct ext2_sb_info *sbi = EXT2_SB(sb);
1679
1680 spin_lock(&sbi->s_lock);
1681 ctx->vals_s_mount_opt = sbi->s_mount_opt;
1682 ctx->vals_s_flags = sb->s_flags;
1683 ctx->s_resuid = sbi->s_resuid;
1684 ctx->s_resgid = sbi->s_resgid;
1685 spin_unlock(&sbi->s_lock);
1686 } else {
1687 ctx->s_sb_block = 1;
1688 ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
1689 }
1690
1691 fc->fs_private = ctx;
1692 fc->ops = &ext2_context_ops;
1693
1694 return 0;
1695 }
1696
1697 static struct file_system_type ext2_fs_type = {
1698 .owner = THIS_MODULE,
1699 .name = "ext2",
1700 .kill_sb = kill_block_super,
1701 .fs_flags = FS_REQUIRES_DEV,
1702 .init_fs_context = ext2_init_fs_context,
1703 .parameters = ext2_param_spec,
1704 };
1705 MODULE_ALIAS_FS("ext2");
1706
init_ext2_fs(void)1707 static int __init init_ext2_fs(void)
1708 {
1709 int err;
1710
1711 err = init_inodecache();
1712 if (err)
1713 return err;
1714 err = register_filesystem(&ext2_fs_type);
1715 if (err)
1716 goto out;
1717 return 0;
1718 out:
1719 destroy_inodecache();
1720 return err;
1721 }
1722
exit_ext2_fs(void)1723 static void __exit exit_ext2_fs(void)
1724 {
1725 unregister_filesystem(&ext2_fs_type);
1726 destroy_inodecache();
1727 }
1728
1729 MODULE_AUTHOR("Remy Card and others");
1730 MODULE_DESCRIPTION("Second Extended Filesystem");
1731 MODULE_LICENSE("GPL");
1732 module_init(init_ext2_fs)
1733 module_exit(exit_ext2_fs)
1734