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: DAX support in ext2 driver is deprecated"
605 " and will be removed at the end of 2025. Please use ext4 driver instead.");
606 ctx_set_mount_opt(ctx, EXT2_MOUNT_DAX);
607 #else
608 ext2_msg_fc(fc, KERN_INFO, "dax option not supported");
609 #endif
610 break;
611
612 #if defined(CONFIG_QUOTA)
613 case Opt_quota:
614 case Opt_usrquota:
615 ctx_set_mount_opt(ctx, EXT2_MOUNT_USRQUOTA);
616 break;
617
618 case Opt_grpquota:
619 ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPQUOTA);
620 break;
621 #else
622 case Opt_quota:
623 case Opt_usrquota:
624 case Opt_grpquota:
625 ext2_msg_fc(fc, KERN_INFO, "quota operations not supported");
626 break;
627 #endif
628 case Opt_reservation:
629 if (!result.negated) {
630 ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
631 ext2_msg_fc(fc, KERN_INFO, "reservations ON");
632 } else {
633 ctx_clear_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
634 ext2_msg_fc(fc, KERN_INFO, "reservations OFF");
635 }
636 break;
637 case Opt_ignore:
638 break;
639 default:
640 return -EINVAL;
641 }
642 return 0;
643 }
644
ext2_setup_super(struct super_block * sb,struct ext2_super_block * es,int read_only)645 static int ext2_setup_super (struct super_block * sb,
646 struct ext2_super_block * es,
647 int read_only)
648 {
649 int res = 0;
650 struct ext2_sb_info *sbi = EXT2_SB(sb);
651
652 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
653 ext2_msg(sb, KERN_ERR,
654 "error: revision level too high, "
655 "forcing read-only mode");
656 res = SB_RDONLY;
657 }
658 if (read_only)
659 return res;
660 if (!(sbi->s_mount_state & EXT2_VALID_FS))
661 ext2_msg(sb, KERN_WARNING,
662 "warning: mounting unchecked fs, "
663 "running e2fsck is recommended");
664 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
665 ext2_msg(sb, KERN_WARNING,
666 "warning: mounting fs with errors, "
667 "running e2fsck is recommended");
668 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
669 le16_to_cpu(es->s_mnt_count) >=
670 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
671 ext2_msg(sb, KERN_WARNING,
672 "warning: maximal mount count reached, "
673 "running e2fsck is recommended");
674 else if (le32_to_cpu(es->s_checkinterval) &&
675 (le32_to_cpu(es->s_lastcheck) +
676 le32_to_cpu(es->s_checkinterval) <=
677 ktime_get_real_seconds()))
678 ext2_msg(sb, KERN_WARNING,
679 "warning: checktime reached, "
680 "running e2fsck is recommended");
681 if (!le16_to_cpu(es->s_max_mnt_count))
682 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
683 le16_add_cpu(&es->s_mnt_count, 1);
684 if (test_opt (sb, DEBUG))
685 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, "
686 "bpg=%lu, ipg=%lu, mo=%04lx]",
687 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
688 sbi->s_groups_count,
689 EXT2_BLOCKS_PER_GROUP(sb),
690 EXT2_INODES_PER_GROUP(sb),
691 sbi->s_mount_opt);
692 return res;
693 }
694
ext2_check_descriptors(struct super_block * sb)695 static int ext2_check_descriptors(struct super_block *sb)
696 {
697 int i;
698 struct ext2_sb_info *sbi = EXT2_SB(sb);
699
700 ext2_debug ("Checking group descriptors");
701
702 for (i = 0; i < sbi->s_groups_count; i++) {
703 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
704 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
705 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i);
706
707 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
708 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
709 {
710 ext2_error (sb, "ext2_check_descriptors",
711 "Block bitmap for group %d"
712 " not in group (block %lu)!",
713 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
714 return 0;
715 }
716 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
717 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
718 {
719 ext2_error (sb, "ext2_check_descriptors",
720 "Inode bitmap for group %d"
721 " not in group (block %lu)!",
722 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
723 return 0;
724 }
725 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
726 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
727 last_block)
728 {
729 ext2_error (sb, "ext2_check_descriptors",
730 "Inode table for group %d"
731 " not in group (block %lu)!",
732 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
733 return 0;
734 }
735 }
736 return 1;
737 }
738
739 /*
740 * Maximal file size. There is a direct, and {,double-,triple-}indirect
741 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
742 * We need to be 1 filesystem block less than the 2^32 sector limit.
743 */
ext2_max_size(int bits)744 static loff_t ext2_max_size(int bits)
745 {
746 loff_t res = EXT2_NDIR_BLOCKS;
747 int meta_blocks;
748 unsigned int upper_limit;
749 unsigned int ppb = 1 << (bits-2);
750
751 /* This is calculated to be the largest file size for a
752 * dense, file such that the total number of
753 * sectors in the file, including data and all indirect blocks,
754 * does not exceed 2^32 -1
755 * __u32 i_blocks representing the total number of
756 * 512 bytes blocks of the file
757 */
758 upper_limit = (1LL << 32) - 1;
759
760 /* total blocks in file system block size */
761 upper_limit >>= (bits - 9);
762
763 /* Compute how many blocks we can address by block tree */
764 res += 1LL << (bits-2);
765 res += 1LL << (2*(bits-2));
766 res += 1LL << (3*(bits-2));
767 /* Compute how many metadata blocks are needed */
768 meta_blocks = 1;
769 meta_blocks += 1 + ppb;
770 meta_blocks += 1 + ppb + ppb * ppb;
771 /* Does block tree limit file size? */
772 if (res + meta_blocks <= upper_limit)
773 goto check_lfs;
774
775 res = upper_limit;
776 /* How many metadata blocks are needed for addressing upper_limit? */
777 upper_limit -= EXT2_NDIR_BLOCKS;
778 /* indirect blocks */
779 meta_blocks = 1;
780 upper_limit -= ppb;
781 /* double indirect blocks */
782 if (upper_limit < ppb * ppb) {
783 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
784 res -= meta_blocks;
785 goto check_lfs;
786 }
787 meta_blocks += 1 + ppb;
788 upper_limit -= ppb * ppb;
789 /* tripple indirect blocks for the rest */
790 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
791 DIV_ROUND_UP(upper_limit, ppb*ppb);
792 res -= meta_blocks;
793 check_lfs:
794 res <<= bits;
795 if (res > MAX_LFS_FILESIZE)
796 res = MAX_LFS_FILESIZE;
797
798 return res;
799 }
800
descriptor_loc(struct super_block * sb,unsigned long logic_sb_block,int nr)801 static unsigned long descriptor_loc(struct super_block *sb,
802 unsigned long logic_sb_block,
803 int nr)
804 {
805 struct ext2_sb_info *sbi = EXT2_SB(sb);
806 unsigned long bg, first_meta_bg;
807
808 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
809
810 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
811 nr < first_meta_bg)
812 return (logic_sb_block + nr + 1);
813 bg = sbi->s_desc_per_block * nr;
814
815 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);
816 }
817
818 /*
819 * Set all mount options either from defaults on disk, or from parsed
820 * options. Parsed/specified options override on-disk defaults.
821 */
ext2_set_options(struct fs_context * fc,struct ext2_sb_info * sbi)822 static void ext2_set_options(struct fs_context *fc, struct ext2_sb_info *sbi)
823 {
824 struct ext2_fs_context *ctx = fc->fs_private;
825 struct ext2_super_block *es = sbi->s_es;
826 unsigned long def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
827
828 /* Copy parsed mount options to sbi */
829 sbi->s_mount_opt = ctx->vals_s_mount_opt;
830
831 /* Use in-superblock defaults only if not specified during parsing */
832 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_DEBUG) &&
833 def_mount_opts & EXT2_DEFM_DEBUG)
834 set_opt(sbi->s_mount_opt, DEBUG);
835
836 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_GRPID) &&
837 def_mount_opts & EXT2_DEFM_BSDGROUPS)
838 set_opt(sbi->s_mount_opt, GRPID);
839
840 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_NO_UID32) &&
841 def_mount_opts & EXT2_DEFM_UID16)
842 set_opt(sbi->s_mount_opt, NO_UID32);
843
844 #ifdef CONFIG_EXT2_FS_XATTR
845 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_XATTR_USER) &&
846 def_mount_opts & EXT2_DEFM_XATTR_USER)
847 set_opt(sbi->s_mount_opt, XATTR_USER);
848 #endif
849 #ifdef CONFIG_EXT2_FS_POSIX_ACL
850 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL) &&
851 def_mount_opts & EXT2_DEFM_ACL)
852 set_opt(sbi->s_mount_opt, POSIX_ACL);
853 #endif
854
855 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK)) {
856 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
857 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
858 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
859 set_opt(sbi->s_mount_opt, ERRORS_CONT);
860 else
861 set_opt(sbi->s_mount_opt, ERRORS_RO);
862 }
863
864 if (ctx->spec & EXT2_SPEC_s_resuid)
865 sbi->s_resuid = ctx->s_resuid;
866 else
867 sbi->s_resuid = make_kuid(&init_user_ns,
868 le16_to_cpu(es->s_def_resuid));
869
870 if (ctx->spec & EXT2_SPEC_s_resgid)
871 sbi->s_resgid = ctx->s_resgid;
872 else
873 sbi->s_resgid = make_kgid(&init_user_ns,
874 le16_to_cpu(es->s_def_resgid));
875 }
876
ext2_fill_super(struct super_block * sb,struct fs_context * fc)877 static int ext2_fill_super(struct super_block *sb, struct fs_context *fc)
878 {
879 struct ext2_fs_context *ctx = fc->fs_private;
880 int silent = fc->sb_flags & SB_SILENT;
881 struct buffer_head * bh;
882 struct ext2_sb_info * sbi;
883 struct ext2_super_block * es;
884 struct inode *root;
885 unsigned long block;
886 unsigned long sb_block = ctx->s_sb_block;
887 unsigned long logic_sb_block;
888 unsigned long offset = 0;
889 long ret = -ENOMEM;
890 int blocksize = BLOCK_SIZE;
891 int db_count;
892 int i, j;
893 __le32 features;
894 int err;
895
896 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
897 if (!sbi)
898 return -ENOMEM;
899
900 sbi->s_blockgroup_lock =
901 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
902 if (!sbi->s_blockgroup_lock) {
903 kfree(sbi);
904 return -ENOMEM;
905 }
906 sb->s_fs_info = sbi;
907 sbi->s_sb_block = sb_block;
908 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
909 NULL, NULL);
910
911 spin_lock_init(&sbi->s_lock);
912 ret = -EINVAL;
913
914 /*
915 * See what the current blocksize for the device is, and
916 * use that as the blocksize. Otherwise (or if the blocksize
917 * is smaller than the default) use the default.
918 * This is important for devices that have a hardware
919 * sectorsize that is larger than the default.
920 */
921 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
922 if (!blocksize) {
923 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
924 goto failed_sbi;
925 }
926
927 /*
928 * If the superblock doesn't start on a hardware sector boundary,
929 * calculate the offset.
930 */
931 if (blocksize != BLOCK_SIZE) {
932 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
933 offset = (sb_block*BLOCK_SIZE) % blocksize;
934 } else {
935 logic_sb_block = sb_block;
936 }
937
938 if (!(bh = sb_bread(sb, logic_sb_block))) {
939 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
940 goto failed_sbi;
941 }
942 /*
943 * Note: s_es must be initialized as soon as possible because
944 * some ext2 macro-instructions depend on its value
945 */
946 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
947 sbi->s_es = es;
948 sb->s_magic = le16_to_cpu(es->s_magic);
949
950 if (sb->s_magic != EXT2_SUPER_MAGIC)
951 goto cantfind_ext2;
952
953 ext2_set_options(fc, sbi);
954
955 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
956 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
957 sb->s_iflags |= SB_I_CGROUPWB;
958
959 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
960 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
961 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
962 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
963 ext2_msg(sb, KERN_WARNING,
964 "warning: feature flags set on rev 0 fs, "
965 "running e2fsck is recommended");
966 /*
967 * Check feature flags regardless of the revision level, since we
968 * previously didn't change the revision level when setting the flags,
969 * so there is a chance incompat flags are set on a rev 0 filesystem.
970 */
971 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
972 if (features) {
973 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
974 "unsupported optional features (%x)",
975 le32_to_cpu(features));
976 goto failed_mount;
977 }
978 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
979 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
980 "unsupported optional features (%x)",
981 le32_to_cpu(features));
982 goto failed_mount;
983 }
984
985 if (le32_to_cpu(es->s_log_block_size) >
986 (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) {
987 ext2_msg(sb, KERN_ERR,
988 "Invalid log block size: %u",
989 le32_to_cpu(es->s_log_block_size));
990 goto failed_mount;
991 }
992 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
993
994 if (test_opt(sb, DAX)) {
995 if (!sbi->s_daxdev) {
996 ext2_msg(sb, KERN_ERR,
997 "DAX unsupported by block device. Turning off DAX.");
998 clear_opt(sbi->s_mount_opt, DAX);
999 } else if (blocksize != PAGE_SIZE) {
1000 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
1001 clear_opt(sbi->s_mount_opt, DAX);
1002 }
1003 }
1004
1005 /* If the blocksize doesn't match, re-read the thing.. */
1006 if (sb->s_blocksize != blocksize) {
1007 brelse(bh);
1008
1009 if (!sb_set_blocksize(sb, blocksize)) {
1010 ext2_msg(sb, KERN_ERR,
1011 "error: bad blocksize %d", blocksize);
1012 goto failed_sbi;
1013 }
1014
1015 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
1016 offset = (sb_block*BLOCK_SIZE) % blocksize;
1017 bh = sb_bread(sb, logic_sb_block);
1018 if(!bh) {
1019 ext2_msg(sb, KERN_ERR, "error: couldn't read"
1020 "superblock on 2nd try");
1021 goto failed_sbi;
1022 }
1023 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
1024 sbi->s_es = es;
1025 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
1026 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
1027 goto failed_mount;
1028 }
1029 }
1030
1031 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
1032 sb->s_max_links = EXT2_LINK_MAX;
1033 sb->s_time_min = S32_MIN;
1034 sb->s_time_max = S32_MAX;
1035
1036 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
1037 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
1038 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
1039 } else {
1040 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1041 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1042 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1043 !is_power_of_2(sbi->s_inode_size) ||
1044 (sbi->s_inode_size > blocksize)) {
1045 ext2_msg(sb, KERN_ERR,
1046 "error: unsupported inode size: %d",
1047 sbi->s_inode_size);
1048 goto failed_mount;
1049 }
1050 }
1051
1052 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1053 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1054
1055 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1056 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1057 goto cantfind_ext2;
1058 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1059 sbi->s_inodes_per_block;
1060 sbi->s_desc_per_block = sb->s_blocksize /
1061 sizeof (struct ext2_group_desc);
1062 sbi->s_sbh = bh;
1063 sbi->s_mount_state = le16_to_cpu(es->s_state);
1064 sbi->s_addr_per_block_bits =
1065 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1066 sbi->s_desc_per_block_bits =
1067 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1068
1069 if (sb->s_magic != EXT2_SUPER_MAGIC)
1070 goto cantfind_ext2;
1071
1072 if (sb->s_blocksize != bh->b_size) {
1073 if (!silent)
1074 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1075 goto failed_mount;
1076 }
1077
1078 if (es->s_log_frag_size != es->s_log_block_size) {
1079 ext2_msg(sb, KERN_ERR,
1080 "error: fragsize log %u != blocksize log %u",
1081 le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits);
1082 goto failed_mount;
1083 }
1084
1085 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1086 ext2_msg(sb, KERN_ERR,
1087 "error: #blocks per group too big: %lu",
1088 sbi->s_blocks_per_group);
1089 goto failed_mount;
1090 }
1091 /* At least inode table, bitmaps, and sb have to fit in one group */
1092 if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) {
1093 ext2_msg(sb, KERN_ERR,
1094 "error: #blocks per group smaller than metadata size: %lu <= %lu",
1095 sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3);
1096 goto failed_mount;
1097 }
1098 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
1099 sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1100 ext2_msg(sb, KERN_ERR,
1101 "error: invalid #inodes per group: %lu",
1102 sbi->s_inodes_per_group);
1103 goto failed_mount;
1104 }
1105 if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) {
1106 ext2_msg(sb, KERN_ERR,
1107 "bad geometry: block count %u exceeds size of device (%u blocks)",
1108 le32_to_cpu(es->s_blocks_count),
1109 (unsigned)sb_bdev_nr_blocks(sb));
1110 goto failed_mount;
1111 }
1112
1113 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1114 le32_to_cpu(es->s_first_data_block) - 1)
1115 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1116 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=
1117 le32_to_cpu(es->s_inodes_count)) {
1118 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",
1119 le32_to_cpu(es->s_inodes_count),
1120 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);
1121 goto failed_mount;
1122 }
1123 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1124 EXT2_DESC_PER_BLOCK(sb);
1125 sbi->s_group_desc = kvmalloc_array(db_count,
1126 sizeof(struct buffer_head *),
1127 GFP_KERNEL);
1128 if (sbi->s_group_desc == NULL) {
1129 ret = -ENOMEM;
1130 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1131 goto failed_mount;
1132 }
1133 bgl_lock_init(sbi->s_blockgroup_lock);
1134 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1135 if (!sbi->s_debts) {
1136 ret = -ENOMEM;
1137 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1138 goto failed_mount_group_desc;
1139 }
1140 for (i = 0; i < db_count; i++) {
1141 block = descriptor_loc(sb, logic_sb_block, i);
1142 sbi->s_group_desc[i] = sb_bread(sb, block);
1143 if (!sbi->s_group_desc[i]) {
1144 for (j = 0; j < i; j++)
1145 brelse (sbi->s_group_desc[j]);
1146 ext2_msg(sb, KERN_ERR,
1147 "error: unable to read group descriptors");
1148 goto failed_mount_group_desc;
1149 }
1150 }
1151 if (!ext2_check_descriptors (sb)) {
1152 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1153 goto failed_mount2;
1154 }
1155 sbi->s_gdb_count = db_count;
1156 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1157 spin_lock_init(&sbi->s_next_gen_lock);
1158
1159 /* per filesystem reservation list head & lock */
1160 spin_lock_init(&sbi->s_rsv_window_lock);
1161 sbi->s_rsv_window_root = RB_ROOT;
1162 /*
1163 * Add a single, static dummy reservation to the start of the
1164 * reservation window list --- it gives us a placeholder for
1165 * append-at-start-of-list which makes the allocation logic
1166 * _much_ simpler.
1167 */
1168 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1169 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1170 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1171 sbi->s_rsv_window_head.rsv_goal_size = 0;
1172 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1173
1174 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1175 ext2_count_free_blocks(sb), GFP_KERNEL);
1176 if (!err) {
1177 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1178 ext2_count_free_inodes(sb), GFP_KERNEL);
1179 }
1180 if (!err) {
1181 err = percpu_counter_init(&sbi->s_dirs_counter,
1182 ext2_count_dirs(sb), GFP_KERNEL);
1183 }
1184 if (err) {
1185 ret = err;
1186 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1187 goto failed_mount3;
1188 }
1189
1190 #ifdef CONFIG_EXT2_FS_XATTR
1191 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1192 if (!sbi->s_ea_block_cache) {
1193 ret = -ENOMEM;
1194 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1195 goto failed_mount3;
1196 }
1197 #endif
1198 /*
1199 * set up enough so that it can read an inode
1200 */
1201 sb->s_op = &ext2_sops;
1202 sb->s_export_op = &ext2_export_ops;
1203 sb->s_xattr = ext2_xattr_handlers;
1204
1205 #ifdef CONFIG_QUOTA
1206 sb->dq_op = &dquot_operations;
1207 sb->s_qcop = &ext2_quotactl_ops;
1208 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1209 #endif
1210
1211 root = ext2_iget(sb, EXT2_ROOT_INO);
1212 if (IS_ERR(root)) {
1213 ret = PTR_ERR(root);
1214 goto failed_mount3;
1215 }
1216 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1217 iput(root);
1218 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1219 goto failed_mount3;
1220 }
1221
1222 sb->s_root = d_make_root(root);
1223 if (!sb->s_root) {
1224 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1225 ret = -ENOMEM;
1226 goto failed_mount3;
1227 }
1228 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1229 ext2_msg(sb, KERN_WARNING,
1230 "warning: mounting ext3 filesystem as ext2");
1231 if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1232 sb->s_flags |= SB_RDONLY;
1233 ext2_write_super(sb);
1234 return 0;
1235
1236 cantfind_ext2:
1237 if (!silent)
1238 ext2_msg(sb, KERN_ERR,
1239 "error: can't find an ext2 filesystem on dev %s.",
1240 sb->s_id);
1241 goto failed_mount;
1242 failed_mount3:
1243 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1244 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1245 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1246 percpu_counter_destroy(&sbi->s_dirs_counter);
1247 failed_mount2:
1248 for (i = 0; i < db_count; i++)
1249 brelse(sbi->s_group_desc[i]);
1250 failed_mount_group_desc:
1251 kvfree(sbi->s_group_desc);
1252 kfree(sbi->s_debts);
1253 failed_mount:
1254 brelse(bh);
1255 failed_sbi:
1256 fs_put_dax(sbi->s_daxdev, NULL);
1257 sb->s_fs_info = NULL;
1258 kfree(sbi->s_blockgroup_lock);
1259 kfree(sbi);
1260 return ret;
1261 }
1262
ext2_clear_super_error(struct super_block * sb)1263 static void ext2_clear_super_error(struct super_block *sb)
1264 {
1265 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1266
1267 if (buffer_write_io_error(sbh)) {
1268 /*
1269 * Oh, dear. A previous attempt to write the
1270 * superblock failed. This could happen because the
1271 * USB device was yanked out. Or it could happen to
1272 * be a transient write error and maybe the block will
1273 * be remapped. Nothing we can do but to retry the
1274 * write and hope for the best.
1275 */
1276 ext2_msg(sb, KERN_ERR,
1277 "previous I/O error to superblock detected");
1278 clear_buffer_write_io_error(sbh);
1279 set_buffer_uptodate(sbh);
1280 }
1281 }
1282
ext2_sync_super(struct super_block * sb,struct ext2_super_block * es,int wait)1283 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1284 int wait)
1285 {
1286 ext2_clear_super_error(sb);
1287 spin_lock(&EXT2_SB(sb)->s_lock);
1288 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1289 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1290 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1291 /* unlock before we do IO */
1292 spin_unlock(&EXT2_SB(sb)->s_lock);
1293 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1294 if (wait)
1295 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1296 }
1297
1298 /*
1299 * In the second extended file system, it is not necessary to
1300 * write the super block since we use a mapping of the
1301 * disk super block in a buffer.
1302 *
1303 * However, this function is still used to set the fs valid
1304 * flags to 0. We need to set this flag to 0 since the fs
1305 * may have been checked while mounted and e2fsck may have
1306 * set s_state to EXT2_VALID_FS after some corrections.
1307 */
ext2_sync_fs(struct super_block * sb,int wait)1308 static int ext2_sync_fs(struct super_block *sb, int wait)
1309 {
1310 struct ext2_sb_info *sbi = EXT2_SB(sb);
1311 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1312
1313 /*
1314 * Write quota structures to quota file, sync_blockdev() will write
1315 * them to disk later
1316 */
1317 dquot_writeback_dquots(sb, -1);
1318
1319 spin_lock(&sbi->s_lock);
1320 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1321 ext2_debug("setting valid to 0\n");
1322 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1323 }
1324 spin_unlock(&sbi->s_lock);
1325 ext2_sync_super(sb, es, wait);
1326 return 0;
1327 }
1328
ext2_freeze(struct super_block * sb)1329 static int ext2_freeze(struct super_block *sb)
1330 {
1331 struct ext2_sb_info *sbi = EXT2_SB(sb);
1332
1333 /*
1334 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1335 * because we have unattached inodes and thus filesystem is not fully
1336 * consistent.
1337 */
1338 if (atomic_long_read(&sb->s_remove_count)) {
1339 ext2_sync_fs(sb, 1);
1340 return 0;
1341 }
1342 /* Set EXT2_FS_VALID flag */
1343 spin_lock(&sbi->s_lock);
1344 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1345 spin_unlock(&sbi->s_lock);
1346 ext2_sync_super(sb, sbi->s_es, 1);
1347
1348 return 0;
1349 }
1350
ext2_unfreeze(struct super_block * sb)1351 static int ext2_unfreeze(struct super_block *sb)
1352 {
1353 /* Just write sb to clear EXT2_VALID_FS flag */
1354 ext2_write_super(sb);
1355
1356 return 0;
1357 }
1358
ext2_write_super(struct super_block * sb)1359 static void ext2_write_super(struct super_block *sb)
1360 {
1361 if (!sb_rdonly(sb))
1362 ext2_sync_fs(sb, 1);
1363 }
1364
ext2_reconfigure(struct fs_context * fc)1365 static int ext2_reconfigure(struct fs_context *fc)
1366 {
1367 struct ext2_fs_context *ctx = fc->fs_private;
1368 struct super_block *sb = fc->root->d_sb;
1369 struct ext2_sb_info * sbi = EXT2_SB(sb);
1370 struct ext2_super_block * es;
1371 struct ext2_mount_options new_opts;
1372 int flags = fc->sb_flags;
1373 int err;
1374
1375 sync_filesystem(sb);
1376
1377 new_opts.s_mount_opt = ctx->vals_s_mount_opt;
1378 new_opts.s_resuid = ctx->s_resuid;
1379 new_opts.s_resgid = ctx->s_resgid;
1380
1381 spin_lock(&sbi->s_lock);
1382 es = sbi->s_es;
1383 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1384 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1385 "dax flag with busy inodes while remounting");
1386 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1387 }
1388 if ((bool)(flags & SB_RDONLY) == sb_rdonly(sb))
1389 goto out_set;
1390 if (flags & SB_RDONLY) {
1391 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1392 !(sbi->s_mount_state & EXT2_VALID_FS))
1393 goto out_set;
1394
1395 /*
1396 * OK, we are remounting a valid rw partition rdonly, so set
1397 * the rdonly flag and then mark the partition as valid again.
1398 */
1399 es->s_state = cpu_to_le16(sbi->s_mount_state);
1400 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1401 spin_unlock(&sbi->s_lock);
1402
1403 err = dquot_suspend(sb, -1);
1404 if (err < 0)
1405 return err;
1406
1407 ext2_sync_super(sb, es, 1);
1408 } else {
1409 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1410 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1411 if (ret) {
1412 spin_unlock(&sbi->s_lock);
1413 ext2_msg(sb, KERN_WARNING,
1414 "warning: couldn't remount RDWR because of "
1415 "unsupported optional features (%x).",
1416 le32_to_cpu(ret));
1417 return -EROFS;
1418 }
1419 /*
1420 * Mounting a RDONLY partition read-write, so reread and
1421 * store the current valid flag. (It may have been changed
1422 * by e2fsck since we originally mounted the partition.)
1423 */
1424 sbi->s_mount_state = le16_to_cpu(es->s_state);
1425 if (!ext2_setup_super (sb, es, 0))
1426 sb->s_flags &= ~SB_RDONLY;
1427 spin_unlock(&sbi->s_lock);
1428
1429 ext2_write_super(sb);
1430
1431 dquot_resume(sb, -1);
1432 }
1433
1434 spin_lock(&sbi->s_lock);
1435 out_set:
1436 sbi->s_mount_opt = new_opts.s_mount_opt;
1437 sbi->s_resuid = new_opts.s_resuid;
1438 sbi->s_resgid = new_opts.s_resgid;
1439 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1440 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
1441 spin_unlock(&sbi->s_lock);
1442
1443 return 0;
1444 }
1445
ext2_statfs(struct dentry * dentry,struct kstatfs * buf)1446 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1447 {
1448 struct super_block *sb = dentry->d_sb;
1449 struct ext2_sb_info *sbi = EXT2_SB(sb);
1450 struct ext2_super_block *es = sbi->s_es;
1451
1452 spin_lock(&sbi->s_lock);
1453
1454 if (test_opt (sb, MINIX_DF))
1455 sbi->s_overhead_last = 0;
1456 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1457 unsigned long i, overhead = 0;
1458 smp_rmb();
1459
1460 /*
1461 * Compute the overhead (FS structures). This is constant
1462 * for a given filesystem unless the number of block groups
1463 * changes so we cache the previous value until it does.
1464 */
1465
1466 /*
1467 * All of the blocks before first_data_block are
1468 * overhead
1469 */
1470 overhead = le32_to_cpu(es->s_first_data_block);
1471
1472 /*
1473 * Add the overhead attributed to the superblock and
1474 * block group descriptors. If the sparse superblocks
1475 * feature is turned on, then not all groups have this.
1476 */
1477 for (i = 0; i < sbi->s_groups_count; i++)
1478 overhead += ext2_bg_has_super(sb, i) +
1479 ext2_bg_num_gdb(sb, i);
1480
1481 /*
1482 * Every block group has an inode bitmap, a block
1483 * bitmap, and an inode table.
1484 */
1485 overhead += (sbi->s_groups_count *
1486 (2 + sbi->s_itb_per_group));
1487 sbi->s_overhead_last = overhead;
1488 smp_wmb();
1489 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1490 }
1491
1492 buf->f_type = EXT2_SUPER_MAGIC;
1493 buf->f_bsize = sb->s_blocksize;
1494 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1495 buf->f_bfree = ext2_count_free_blocks(sb);
1496 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1497 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1498 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1499 buf->f_bavail = 0;
1500 buf->f_files = le32_to_cpu(es->s_inodes_count);
1501 buf->f_ffree = ext2_count_free_inodes(sb);
1502 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1503 buf->f_namelen = EXT2_NAME_LEN;
1504 buf->f_fsid = uuid_to_fsid(es->s_uuid);
1505 spin_unlock(&sbi->s_lock);
1506 return 0;
1507 }
1508
ext2_get_tree(struct fs_context * fc)1509 static int ext2_get_tree(struct fs_context *fc)
1510 {
1511 return get_tree_bdev(fc, ext2_fill_super);
1512 }
1513
1514 #ifdef CONFIG_QUOTA
1515
1516 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1517 * acquiring the locks... As quota files are never truncated and quota code
1518 * itself serializes the operations (and no one else should touch the files)
1519 * 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)1520 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1521 size_t len, loff_t off)
1522 {
1523 struct inode *inode = sb_dqopt(sb)->files[type];
1524 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1525 int err = 0;
1526 int offset = off & (sb->s_blocksize - 1);
1527 int tocopy;
1528 size_t toread;
1529 struct buffer_head tmp_bh;
1530 struct buffer_head *bh;
1531 loff_t i_size = i_size_read(inode);
1532
1533 if (off > i_size)
1534 return 0;
1535 if (off+len > i_size)
1536 len = i_size-off;
1537 toread = len;
1538 while (toread > 0) {
1539 tocopy = min_t(size_t, sb->s_blocksize - offset, toread);
1540
1541 tmp_bh.b_state = 0;
1542 tmp_bh.b_size = sb->s_blocksize;
1543 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1544 if (err < 0)
1545 return err;
1546 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1547 memset(data, 0, tocopy);
1548 else {
1549 bh = sb_bread(sb, tmp_bh.b_blocknr);
1550 if (!bh)
1551 return -EIO;
1552 memcpy(data, bh->b_data+offset, tocopy);
1553 brelse(bh);
1554 }
1555 offset = 0;
1556 toread -= tocopy;
1557 data += tocopy;
1558 blk++;
1559 }
1560 return len;
1561 }
1562
1563 /* Write to quotafile */
ext2_quota_write(struct super_block * sb,int type,const char * data,size_t len,loff_t off)1564 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1565 const char *data, size_t len, loff_t off)
1566 {
1567 struct inode *inode = sb_dqopt(sb)->files[type];
1568 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1569 int err = 0;
1570 int offset = off & (sb->s_blocksize - 1);
1571 int tocopy;
1572 size_t towrite = len;
1573 struct buffer_head tmp_bh;
1574 struct buffer_head *bh;
1575
1576 while (towrite > 0) {
1577 tocopy = min_t(size_t, sb->s_blocksize - offset, towrite);
1578
1579 tmp_bh.b_state = 0;
1580 tmp_bh.b_size = sb->s_blocksize;
1581 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1582 if (err < 0)
1583 goto out;
1584 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1585 bh = sb_bread(sb, tmp_bh.b_blocknr);
1586 else
1587 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1588 if (unlikely(!bh)) {
1589 err = -EIO;
1590 goto out;
1591 }
1592 lock_buffer(bh);
1593 memcpy(bh->b_data+offset, data, tocopy);
1594 flush_dcache_folio(bh->b_folio);
1595 set_buffer_uptodate(bh);
1596 mark_buffer_dirty(bh);
1597 unlock_buffer(bh);
1598 brelse(bh);
1599 offset = 0;
1600 towrite -= tocopy;
1601 data += tocopy;
1602 blk++;
1603 }
1604 out:
1605 if (len == towrite)
1606 return err;
1607 if (inode->i_size < off+len-towrite)
1608 i_size_write(inode, off+len-towrite);
1609 inode_inc_iversion(inode);
1610 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1611 mark_inode_dirty(inode);
1612 return len - towrite;
1613 }
1614
ext2_quota_on(struct super_block * sb,int type,int format_id,const struct path * path)1615 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1616 const struct path *path)
1617 {
1618 int err;
1619 struct inode *inode;
1620
1621 err = dquot_quota_on(sb, type, format_id, path);
1622 if (err)
1623 return err;
1624
1625 inode = d_inode(path->dentry);
1626 inode_lock(inode);
1627 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1628 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1629 S_NOATIME | S_IMMUTABLE);
1630 inode_unlock(inode);
1631 mark_inode_dirty(inode);
1632
1633 return 0;
1634 }
1635
ext2_quota_off(struct super_block * sb,int type)1636 static int ext2_quota_off(struct super_block *sb, int type)
1637 {
1638 struct inode *inode = sb_dqopt(sb)->files[type];
1639 int err;
1640
1641 if (!inode || !igrab(inode))
1642 goto out;
1643
1644 err = dquot_quota_off(sb, type);
1645 if (err)
1646 goto out_put;
1647
1648 inode_lock(inode);
1649 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1650 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1651 inode_unlock(inode);
1652 mark_inode_dirty(inode);
1653 out_put:
1654 iput(inode);
1655 return err;
1656 out:
1657 return dquot_quota_off(sb, type);
1658 }
1659
1660 #endif
1661
1662 static const struct fs_context_operations ext2_context_ops = {
1663 .parse_param = ext2_parse_param,
1664 .get_tree = ext2_get_tree,
1665 .reconfigure = ext2_reconfigure,
1666 .free = ext2_free_fc,
1667 };
1668
ext2_init_fs_context(struct fs_context * fc)1669 static int ext2_init_fs_context(struct fs_context *fc)
1670 {
1671 struct ext2_fs_context *ctx;
1672
1673 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1674 if (!ctx)
1675 return -ENOMEM;
1676
1677 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
1678 struct super_block *sb = fc->root->d_sb;
1679 struct ext2_sb_info *sbi = EXT2_SB(sb);
1680
1681 spin_lock(&sbi->s_lock);
1682 ctx->vals_s_mount_opt = sbi->s_mount_opt;
1683 ctx->vals_s_flags = sb->s_flags;
1684 ctx->s_resuid = sbi->s_resuid;
1685 ctx->s_resgid = sbi->s_resgid;
1686 spin_unlock(&sbi->s_lock);
1687 } else {
1688 ctx->s_sb_block = 1;
1689 ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
1690 }
1691
1692 fc->fs_private = ctx;
1693 fc->ops = &ext2_context_ops;
1694
1695 return 0;
1696 }
1697
1698 static struct file_system_type ext2_fs_type = {
1699 .owner = THIS_MODULE,
1700 .name = "ext2",
1701 .kill_sb = kill_block_super,
1702 .fs_flags = FS_REQUIRES_DEV,
1703 .init_fs_context = ext2_init_fs_context,
1704 .parameters = ext2_param_spec,
1705 };
1706 MODULE_ALIAS_FS("ext2");
1707
init_ext2_fs(void)1708 static int __init init_ext2_fs(void)
1709 {
1710 int err;
1711
1712 err = init_inodecache();
1713 if (err)
1714 return err;
1715 err = register_filesystem(&ext2_fs_type);
1716 if (err)
1717 goto out;
1718 return 0;
1719 out:
1720 destroy_inodecache();
1721 return err;
1722 }
1723
exit_ext2_fs(void)1724 static void __exit exit_ext2_fs(void)
1725 {
1726 unregister_filesystem(&ext2_fs_type);
1727 destroy_inodecache();
1728 }
1729
1730 MODULE_AUTHOR("Remy Card and others");
1731 MODULE_DESCRIPTION("Second Extended Filesystem");
1732 MODULE_LICENSE("GPL");
1733 module_init(init_ext2_fs)
1734 module_exit(exit_ext2_fs)
1735