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fanotify: merge duplicate events on parent and child
[linux/fpc-iii.git] / fs / ext2 / super.c
blob4a4ab683250df231a31f1713c30b3633e3eb7043
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/parser.h>
27 #include <linux/random.h>
28 #include <linux/buffer_head.h>
29 #include <linux/exportfs.h>
30 #include <linux/vfs.h>
31 #include <linux/seq_file.h>
32 #include <linux/mount.h>
33 #include <linux/log2.h>
34 #include <linux/quotaops.h>
35 #include <linux/uaccess.h>
36 #include <linux/dax.h>
37 #include <linux/iversion.h>
38 #include "ext2.h"
39 #include "xattr.h"
40 #include "acl.h"
41
42 static void ext2_write_super(struct super_block *sb);
43 static int ext2_remount (struct super_block * sb, int * flags, char * data);
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
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
84 void ext2_msg(struct super_block *sb, const char *prefix,
85 const char *fmt, ...)
86 {
87 struct va_format vaf;
88 va_list args;
89
90 va_start(args, fmt);
91
92 vaf.fmt = fmt;
93 vaf.va = &args;
94
95 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
96
97 va_end(args);
98 }
99
100 /*
101 * This must be called with sbi->s_lock held.
102 */
103 void ext2_update_dynamic_rev(struct super_block *sb)
104 {
105 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
106
107 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
108 return;
109
110 ext2_msg(sb, KERN_WARNING,
111 "warning: updating to rev %d because of "
112 "new feature flag, running e2fsck is recommended",
113 EXT2_DYNAMIC_REV);
114
115 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
116 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
117 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
118 /* leave es->s_feature_*compat flags alone */
119 /* es->s_uuid will be set by e2fsck if empty */
120
121 /*
122 * The rest of the superblock fields should be zero, and if not it
123 * means they are likely already in use, so leave them alone. We
124 * can leave it up to e2fsck to clean up any inconsistencies there.
125 */
126 }
127
128 #ifdef CONFIG_QUOTA
129 static int ext2_quota_off(struct super_block *sb, int type);
130
131 static void ext2_quota_off_umount(struct super_block *sb)
132 {
133 int type;
134
135 for (type = 0; type < MAXQUOTAS; type++)
136 ext2_quota_off(sb, type);
137 }
138 #else
139 static inline void ext2_quota_off_umount(struct super_block *sb)
140 {
141 }
142 #endif
143
144 static void ext2_put_super (struct super_block * sb)
145 {
146 int db_count;
147 int i;
148 struct ext2_sb_info *sbi = EXT2_SB(sb);
149
150 ext2_quota_off_umount(sb);
151
152 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
153 sbi->s_ea_block_cache = NULL;
154
155 if (!sb_rdonly(sb)) {
156 struct ext2_super_block *es = sbi->s_es;
157
158 spin_lock(&sbi->s_lock);
159 es->s_state = cpu_to_le16(sbi->s_mount_state);
160 spin_unlock(&sbi->s_lock);
161 ext2_sync_super(sb, es, 1);
162 }
163 db_count = sbi->s_gdb_count;
164 for (i = 0; i < db_count; i++)
165 brelse(sbi->s_group_desc[i]);
166 kfree(sbi->s_group_desc);
167 kfree(sbi->s_debts);
168 percpu_counter_destroy(&sbi->s_freeblocks_counter);
169 percpu_counter_destroy(&sbi->s_freeinodes_counter);
170 percpu_counter_destroy(&sbi->s_dirs_counter);
171 brelse (sbi->s_sbh);
172 sb->s_fs_info = NULL;
173 kfree(sbi->s_blockgroup_lock);
174 fs_put_dax(sbi->s_daxdev);
175 kfree(sbi);
176 }
177
178 static struct kmem_cache * ext2_inode_cachep;
179
180 static struct inode *ext2_alloc_inode(struct super_block *sb)
181 {
182 struct ext2_inode_info *ei;
183 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
184 if (!ei)
185 return NULL;
186 ei->i_block_alloc_info = NULL;
187 inode_set_iversion(&ei->vfs_inode, 1);
188 #ifdef CONFIG_QUOTA
189 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
190 #endif
191
192 return &ei->vfs_inode;
193 }
194
195 static void ext2_free_in_core_inode(struct inode *inode)
196 {
197 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
198 }
199
200 static void init_once(void *foo)
201 {
202 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
203
204 rwlock_init(&ei->i_meta_lock);
205 #ifdef CONFIG_EXT2_FS_XATTR
206 init_rwsem(&ei->xattr_sem);
207 #endif
208 mutex_init(&ei->truncate_mutex);
209 #ifdef CONFIG_FS_DAX
210 init_rwsem(&ei->dax_sem);
211 #endif
212 inode_init_once(&ei->vfs_inode);
213 }
214
215 static int __init init_inodecache(void)
216 {
217 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",
218 sizeof(struct ext2_inode_info), 0,
219 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
220 SLAB_ACCOUNT),
221 offsetof(struct ext2_inode_info, i_data),
222 sizeof_field(struct ext2_inode_info, i_data),
223 init_once);
224 if (ext2_inode_cachep == NULL)
225 return -ENOMEM;
226 return 0;
227 }
228
229 static void destroy_inodecache(void)
230 {
231 /*
232 * Make sure all delayed rcu free inodes are flushed before we
233 * destroy cache.
234 */
235 rcu_barrier();
236 kmem_cache_destroy(ext2_inode_cachep);
237 }
238
239 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
240 {
241 struct super_block *sb = root->d_sb;
242 struct ext2_sb_info *sbi = EXT2_SB(sb);
243 struct ext2_super_block *es = sbi->s_es;
244 unsigned long def_mount_opts;
245
246 spin_lock(&sbi->s_lock);
247 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
248
249 if (sbi->s_sb_block != 1)
250 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
251 if (test_opt(sb, MINIX_DF))
252 seq_puts(seq, ",minixdf");
253 if (test_opt(sb, GRPID))
254 seq_puts(seq, ",grpid");
255 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
256 seq_puts(seq, ",nogrpid");
257 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
258 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
259 seq_printf(seq, ",resuid=%u",
260 from_kuid_munged(&init_user_ns, sbi->s_resuid));
261 }
262 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
263 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
264 seq_printf(seq, ",resgid=%u",
265 from_kgid_munged(&init_user_ns, sbi->s_resgid));
266 }
267 if (test_opt(sb, ERRORS_RO)) {
268 int def_errors = le16_to_cpu(es->s_errors);
269
270 if (def_errors == EXT2_ERRORS_PANIC ||
271 def_errors == EXT2_ERRORS_CONTINUE) {
272 seq_puts(seq, ",errors=remount-ro");
273 }
274 }
275 if (test_opt(sb, ERRORS_CONT))
276 seq_puts(seq, ",errors=continue");
277 if (test_opt(sb, ERRORS_PANIC))
278 seq_puts(seq, ",errors=panic");
279 if (test_opt(sb, NO_UID32))
280 seq_puts(seq, ",nouid32");
281 if (test_opt(sb, DEBUG))
282 seq_puts(seq, ",debug");
283 if (test_opt(sb, OLDALLOC))
284 seq_puts(seq, ",oldalloc");
285
286 #ifdef CONFIG_EXT2_FS_XATTR
287 if (test_opt(sb, XATTR_USER))
288 seq_puts(seq, ",user_xattr");
289 if (!test_opt(sb, XATTR_USER) &&
290 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
291 seq_puts(seq, ",nouser_xattr");
292 }
293 #endif
294
295 #ifdef CONFIG_EXT2_FS_POSIX_ACL
296 if (test_opt(sb, POSIX_ACL))
297 seq_puts(seq, ",acl");
298 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
299 seq_puts(seq, ",noacl");
300 #endif
301
302 if (test_opt(sb, NOBH))
303 seq_puts(seq, ",nobh");
304
305 if (test_opt(sb, USRQUOTA))
306 seq_puts(seq, ",usrquota");
307
308 if (test_opt(sb, GRPQUOTA))
309 seq_puts(seq, ",grpquota");
310
311 if (test_opt(sb, XIP))
312 seq_puts(seq, ",xip");
313
314 if (test_opt(sb, DAX))
315 seq_puts(seq, ",dax");
316
317 if (!test_opt(sb, RESERVATION))
318 seq_puts(seq, ",noreservation");
319
320 spin_unlock(&sbi->s_lock);
321 return 0;
322 }
323
324 #ifdef CONFIG_QUOTA
325 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
326 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
327 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
328 const struct path *path);
329 static struct dquot **ext2_get_dquots(struct inode *inode)
330 {
331 return EXT2_I(inode)->i_dquot;
332 }
333
334 static const struct quotactl_ops ext2_quotactl_ops = {
335 .quota_on = ext2_quota_on,
336 .quota_off = ext2_quota_off,
337 .quota_sync = dquot_quota_sync,
338 .get_state = dquot_get_state,
339 .set_info = dquot_set_dqinfo,
340 .get_dqblk = dquot_get_dqblk,
341 .set_dqblk = dquot_set_dqblk,
342 .get_nextdqblk = dquot_get_next_dqblk,
343 };
344 #endif
345
346 static const struct super_operations ext2_sops = {
347 .alloc_inode = ext2_alloc_inode,
348 .free_inode = ext2_free_in_core_inode,
349 .write_inode = ext2_write_inode,
350 .evict_inode = ext2_evict_inode,
351 .put_super = ext2_put_super,
352 .sync_fs = ext2_sync_fs,
353 .freeze_fs = ext2_freeze,
354 .unfreeze_fs = ext2_unfreeze,
355 .statfs = ext2_statfs,
356 .remount_fs = ext2_remount,
357 .show_options = ext2_show_options,
358 #ifdef CONFIG_QUOTA
359 .quota_read = ext2_quota_read,
360 .quota_write = ext2_quota_write,
361 .get_dquots = ext2_get_dquots,
362 #endif
363 };
364
365 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
366 u64 ino, u32 generation)
367 {
368 struct inode *inode;
369
370 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
371 return ERR_PTR(-ESTALE);
372 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
373 return ERR_PTR(-ESTALE);
374
375 /*
376 * ext2_iget isn't quite right if the inode is currently unallocated!
377 * However ext2_iget currently does appropriate checks to handle stale
378 * inodes so everything is OK.
379 */
380 inode = ext2_iget(sb, ino);
381 if (IS_ERR(inode))
382 return ERR_CAST(inode);
383 if (generation && inode->i_generation != generation) {
384 /* we didn't find the right inode.. */
385 iput(inode);
386 return ERR_PTR(-ESTALE);
387 }
388 return inode;
389 }
390
391 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
392 int fh_len, int fh_type)
393 {
394 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
395 ext2_nfs_get_inode);
396 }
397
398 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
399 int fh_len, int fh_type)
400 {
401 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
402 ext2_nfs_get_inode);
403 }
404
405 static const struct export_operations ext2_export_ops = {
406 .fh_to_dentry = ext2_fh_to_dentry,
407 .fh_to_parent = ext2_fh_to_parent,
408 .get_parent = ext2_get_parent,
409 };
410
411 static unsigned long get_sb_block(void **data)
412 {
413 unsigned long sb_block;
414 char *options = (char *) *data;
415
416 if (!options || strncmp(options, "sb=", 3) != 0)
417 return 1; /* Default location */
418 options += 3;
419 sb_block = simple_strtoul(options, &options, 0);
420 if (*options && *options != ',') {
421 printk("EXT2-fs: Invalid sb specification: %s\n",
422 (char *) *data);
423 return 1;
424 }
425 if (*options == ',')
426 options++;
427 *data = (void *) options;
428 return sb_block;
429 }
430
431 enum {
432 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
433 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
434 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
435 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
436 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
437 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
438 };
439
440 static const match_table_t tokens = {
441 {Opt_bsd_df, "bsddf"},
442 {Opt_minix_df, "minixdf"},
443 {Opt_grpid, "grpid"},
444 {Opt_grpid, "bsdgroups"},
445 {Opt_nogrpid, "nogrpid"},
446 {Opt_nogrpid, "sysvgroups"},
447 {Opt_resgid, "resgid=%u"},
448 {Opt_resuid, "resuid=%u"},
449 {Opt_sb, "sb=%u"},
450 {Opt_err_cont, "errors=continue"},
451 {Opt_err_panic, "errors=panic"},
452 {Opt_err_ro, "errors=remount-ro"},
453 {Opt_nouid32, "nouid32"},
454 {Opt_nocheck, "check=none"},
455 {Opt_nocheck, "nocheck"},
456 {Opt_debug, "debug"},
457 {Opt_oldalloc, "oldalloc"},
458 {Opt_orlov, "orlov"},
459 {Opt_nobh, "nobh"},
460 {Opt_user_xattr, "user_xattr"},
461 {Opt_nouser_xattr, "nouser_xattr"},
462 {Opt_acl, "acl"},
463 {Opt_noacl, "noacl"},
464 {Opt_xip, "xip"},
465 {Opt_dax, "dax"},
466 {Opt_grpquota, "grpquota"},
467 {Opt_ignore, "noquota"},
468 {Opt_quota, "quota"},
469 {Opt_usrquota, "usrquota"},
470 {Opt_reservation, "reservation"},
471 {Opt_noreservation, "noreservation"},
472 {Opt_err, NULL}
473 };
474
475 static int parse_options(char *options, struct super_block *sb,
476 struct ext2_mount_options *opts)
477 {
478 char *p;
479 substring_t args[MAX_OPT_ARGS];
480 int option;
481 kuid_t uid;
482 kgid_t gid;
483
484 if (!options)
485 return 1;
486
487 while ((p = strsep (&options, ",")) != NULL) {
488 int token;
489 if (!*p)
490 continue;
491
492 token = match_token(p, tokens, args);
493 switch (token) {
494 case Opt_bsd_df:
495 clear_opt (opts->s_mount_opt, MINIX_DF);
496 break;
497 case Opt_minix_df:
498 set_opt (opts->s_mount_opt, MINIX_DF);
499 break;
500 case Opt_grpid:
501 set_opt (opts->s_mount_opt, GRPID);
502 break;
503 case Opt_nogrpid:
504 clear_opt (opts->s_mount_opt, GRPID);
505 break;
506 case Opt_resuid:
507 if (match_int(&args[0], &option))
508 return 0;
509 uid = make_kuid(current_user_ns(), option);
510 if (!uid_valid(uid)) {
511 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
512 return 0;
513
514 }
515 opts->s_resuid = uid;
516 break;
517 case Opt_resgid:
518 if (match_int(&args[0], &option))
519 return 0;
520 gid = make_kgid(current_user_ns(), option);
521 if (!gid_valid(gid)) {
522 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
523 return 0;
524 }
525 opts->s_resgid = gid;
526 break;
527 case Opt_sb:
528 /* handled by get_sb_block() instead of here */
529 /* *sb_block = match_int(&args[0]); */
530 break;
531 case Opt_err_panic:
532 clear_opt (opts->s_mount_opt, ERRORS_CONT);
533 clear_opt (opts->s_mount_opt, ERRORS_RO);
534 set_opt (opts->s_mount_opt, ERRORS_PANIC);
535 break;
536 case Opt_err_ro:
537 clear_opt (opts->s_mount_opt, ERRORS_CONT);
538 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
539 set_opt (opts->s_mount_opt, ERRORS_RO);
540 break;
541 case Opt_err_cont:
542 clear_opt (opts->s_mount_opt, ERRORS_RO);
543 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
544 set_opt (opts->s_mount_opt, ERRORS_CONT);
545 break;
546 case Opt_nouid32:
547 set_opt (opts->s_mount_opt, NO_UID32);
548 break;
549 case Opt_nocheck:
550 ext2_msg(sb, KERN_WARNING,
551 "Option nocheck/check=none is deprecated and"
552 " will be removed in June 2020.");
553 clear_opt (opts->s_mount_opt, CHECK);
554 break;
555 case Opt_debug:
556 set_opt (opts->s_mount_opt, DEBUG);
557 break;
558 case Opt_oldalloc:
559 set_opt (opts->s_mount_opt, OLDALLOC);
560 break;
561 case Opt_orlov:
562 clear_opt (opts->s_mount_opt, OLDALLOC);
563 break;
564 case Opt_nobh:
565 set_opt (opts->s_mount_opt, NOBH);
566 break;
567 #ifdef CONFIG_EXT2_FS_XATTR
568 case Opt_user_xattr:
569 set_opt (opts->s_mount_opt, XATTR_USER);
570 break;
571 case Opt_nouser_xattr:
572 clear_opt (opts->s_mount_opt, XATTR_USER);
573 break;
574 #else
575 case Opt_user_xattr:
576 case Opt_nouser_xattr:
577 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
578 "not supported");
579 break;
580 #endif
581 #ifdef CONFIG_EXT2_FS_POSIX_ACL
582 case Opt_acl:
583 set_opt(opts->s_mount_opt, POSIX_ACL);
584 break;
585 case Opt_noacl:
586 clear_opt(opts->s_mount_opt, POSIX_ACL);
587 break;
588 #else
589 case Opt_acl:
590 case Opt_noacl:
591 ext2_msg(sb, KERN_INFO,
592 "(no)acl options not supported");
593 break;
594 #endif
595 case Opt_xip:
596 ext2_msg(sb, KERN_INFO, "use dax instead of xip");
597 set_opt(opts->s_mount_opt, XIP);
598 /* Fall through */
599 case Opt_dax:
600 #ifdef CONFIG_FS_DAX
601 ext2_msg(sb, KERN_WARNING,
602 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
603 set_opt(opts->s_mount_opt, DAX);
604 #else
605 ext2_msg(sb, KERN_INFO, "dax option not supported");
606 #endif
607 break;
608
609 #if defined(CONFIG_QUOTA)
610 case Opt_quota:
611 case Opt_usrquota:
612 set_opt(opts->s_mount_opt, USRQUOTA);
613 break;
614
615 case Opt_grpquota:
616 set_opt(opts->s_mount_opt, GRPQUOTA);
617 break;
618 #else
619 case Opt_quota:
620 case Opt_usrquota:
621 case Opt_grpquota:
622 ext2_msg(sb, KERN_INFO,
623 "quota operations not supported");
624 break;
625 #endif
626
627 case Opt_reservation:
628 set_opt(opts->s_mount_opt, RESERVATION);
629 ext2_msg(sb, KERN_INFO, "reservations ON");
630 break;
631 case Opt_noreservation:
632 clear_opt(opts->s_mount_opt, RESERVATION);
633 ext2_msg(sb, KERN_INFO, "reservations OFF");
634 break;
635 case Opt_ignore:
636 break;
637 default:
638 return 0;
639 }
640 }
641 return 1;
642 }
643
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, fs=%lu, gc=%lu, "
685 "bpg=%lu, ipg=%lu, mo=%04lx]",
686 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
687 sbi->s_frag_size,
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
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 */
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 /* Does block tree limit file size? */
768 if (res < upper_limit)
769 goto check_lfs;
770
771 res = upper_limit;
772 /* How many metadata blocks are needed for addressing upper_limit? */
773 upper_limit -= EXT2_NDIR_BLOCKS;
774 /* indirect blocks */
775 meta_blocks = 1;
776 upper_limit -= ppb;
777 /* double indirect blocks */
778 if (upper_limit < ppb * ppb) {
779 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
780 res -= meta_blocks;
781 goto check_lfs;
782 }
783 meta_blocks += 1 + ppb;
784 upper_limit -= ppb * ppb;
785 /* tripple indirect blocks for the rest */
786 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
787 DIV_ROUND_UP(upper_limit, ppb*ppb);
788 res -= meta_blocks;
789 check_lfs:
790 res <<= bits;
791 if (res > MAX_LFS_FILESIZE)
792 res = MAX_LFS_FILESIZE;
793
794 return res;
795 }
796
797 static unsigned long descriptor_loc(struct super_block *sb,
798 unsigned long logic_sb_block,
799 int nr)
800 {
801 struct ext2_sb_info *sbi = EXT2_SB(sb);
802 unsigned long bg, first_meta_bg;
803
804 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
805
806 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
807 nr < first_meta_bg)
808 return (logic_sb_block + nr + 1);
809 bg = sbi->s_desc_per_block * nr;
810
811 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);
812 }
813
814 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
815 {
816 struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
817 struct buffer_head * bh;
818 struct ext2_sb_info * sbi;
819 struct ext2_super_block * es;
820 struct inode *root;
821 unsigned long block;
822 unsigned long sb_block = get_sb_block(&data);
823 unsigned long logic_sb_block;
824 unsigned long offset = 0;
825 unsigned long def_mount_opts;
826 long ret = -ENOMEM;
827 int blocksize = BLOCK_SIZE;
828 int db_count;
829 int i, j;
830 __le32 features;
831 int err;
832 struct ext2_mount_options opts;
833
834 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
835 if (!sbi)
836 goto failed;
837
838 sbi->s_blockgroup_lock =
839 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
840 if (!sbi->s_blockgroup_lock) {
841 kfree(sbi);
842 goto failed;
843 }
844 sb->s_fs_info = sbi;
845 sbi->s_sb_block = sb_block;
846 sbi->s_daxdev = dax_dev;
847
848 spin_lock_init(&sbi->s_lock);
849 ret = -EINVAL;
850
851 /*
852 * See what the current blocksize for the device is, and
853 * use that as the blocksize. Otherwise (or if the blocksize
854 * is smaller than the default) use the default.
855 * This is important for devices that have a hardware
856 * sectorsize that is larger than the default.
857 */
858 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
859 if (!blocksize) {
860 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
861 goto failed_sbi;
862 }
863
864 /*
865 * If the superblock doesn't start on a hardware sector boundary,
866 * calculate the offset.
867 */
868 if (blocksize != BLOCK_SIZE) {
869 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
870 offset = (sb_block*BLOCK_SIZE) % blocksize;
871 } else {
872 logic_sb_block = sb_block;
873 }
874
875 if (!(bh = sb_bread(sb, logic_sb_block))) {
876 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
877 goto failed_sbi;
878 }
879 /*
880 * Note: s_es must be initialized as soon as possible because
881 * some ext2 macro-instructions depend on its value
882 */
883 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
884 sbi->s_es = es;
885 sb->s_magic = le16_to_cpu(es->s_magic);
886
887 if (sb->s_magic != EXT2_SUPER_MAGIC)
888 goto cantfind_ext2;
889
890 opts.s_mount_opt = 0;
891 /* Set defaults before we parse the mount options */
892 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
893 if (def_mount_opts & EXT2_DEFM_DEBUG)
894 set_opt(opts.s_mount_opt, DEBUG);
895 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
896 set_opt(opts.s_mount_opt, GRPID);
897 if (def_mount_opts & EXT2_DEFM_UID16)
898 set_opt(opts.s_mount_opt, NO_UID32);
899 #ifdef CONFIG_EXT2_FS_XATTR
900 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
901 set_opt(opts.s_mount_opt, XATTR_USER);
902 #endif
903 #ifdef CONFIG_EXT2_FS_POSIX_ACL
904 if (def_mount_opts & EXT2_DEFM_ACL)
905 set_opt(opts.s_mount_opt, POSIX_ACL);
906 #endif
907
908 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
909 set_opt(opts.s_mount_opt, ERRORS_PANIC);
910 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
911 set_opt(opts.s_mount_opt, ERRORS_CONT);
912 else
913 set_opt(opts.s_mount_opt, ERRORS_RO);
914
915 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
916 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
917
918 set_opt(opts.s_mount_opt, RESERVATION);
919
920 if (!parse_options((char *) data, sb, &opts))
921 goto failed_mount;
922
923 sbi->s_mount_opt = opts.s_mount_opt;
924 sbi->s_resuid = opts.s_resuid;
925 sbi->s_resgid = opts.s_resgid;
926
927 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
928 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
929 sb->s_iflags |= SB_I_CGROUPWB;
930
931 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
932 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
933 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
934 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
935 ext2_msg(sb, KERN_WARNING,
936 "warning: feature flags set on rev 0 fs, "
937 "running e2fsck is recommended");
938 /*
939 * Check feature flags regardless of the revision level, since we
940 * previously didn't change the revision level when setting the flags,
941 * so there is a chance incompat flags are set on a rev 0 filesystem.
942 */
943 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
944 if (features) {
945 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
946 "unsupported optional features (%x)",
947 le32_to_cpu(features));
948 goto failed_mount;
949 }
950 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
951 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
952 "unsupported optional features (%x)",
953 le32_to_cpu(features));
954 goto failed_mount;
955 }
956
957 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
958
959 if (test_opt(sb, DAX)) {
960 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
961 ext2_msg(sb, KERN_ERR,
962 "DAX unsupported by block device. Turning off DAX.");
963 clear_opt(sbi->s_mount_opt, DAX);
964 }
965 }
966
967 /* If the blocksize doesn't match, re-read the thing.. */
968 if (sb->s_blocksize != blocksize) {
969 brelse(bh);
970
971 if (!sb_set_blocksize(sb, blocksize)) {
972 ext2_msg(sb, KERN_ERR,
973 "error: bad blocksize %d", blocksize);
974 goto failed_sbi;
975 }
976
977 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
978 offset = (sb_block*BLOCK_SIZE) % blocksize;
979 bh = sb_bread(sb, logic_sb_block);
980 if(!bh) {
981 ext2_msg(sb, KERN_ERR, "error: couldn't read"
982 "superblock on 2nd try");
983 goto failed_sbi;
984 }
985 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
986 sbi->s_es = es;
987 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
988 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
989 goto failed_mount;
990 }
991 }
992
993 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
994 sb->s_max_links = EXT2_LINK_MAX;
995 sb->s_time_min = S32_MIN;
996 sb->s_time_max = S32_MAX;
997
998 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
999 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
1000 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
1001 } else {
1002 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1003 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1004 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1005 !is_power_of_2(sbi->s_inode_size) ||
1006 (sbi->s_inode_size > blocksize)) {
1007 ext2_msg(sb, KERN_ERR,
1008 "error: unsupported inode size: %d",
1009 sbi->s_inode_size);
1010 goto failed_mount;
1011 }
1012 }
1013
1014 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
1015 le32_to_cpu(es->s_log_frag_size);
1016 if (sbi->s_frag_size == 0)
1017 goto cantfind_ext2;
1018 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
1019
1020 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1021 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1022 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1023
1024 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1025 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1026 goto cantfind_ext2;
1027 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1028 sbi->s_inodes_per_block;
1029 sbi->s_desc_per_block = sb->s_blocksize /
1030 sizeof (struct ext2_group_desc);
1031 sbi->s_sbh = bh;
1032 sbi->s_mount_state = le16_to_cpu(es->s_state);
1033 sbi->s_addr_per_block_bits =
1034 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1035 sbi->s_desc_per_block_bits =
1036 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1037
1038 if (sb->s_magic != EXT2_SUPER_MAGIC)
1039 goto cantfind_ext2;
1040
1041 if (sb->s_blocksize != bh->b_size) {
1042 if (!silent)
1043 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1044 goto failed_mount;
1045 }
1046
1047 if (sb->s_blocksize != sbi->s_frag_size) {
1048 ext2_msg(sb, KERN_ERR,
1049 "error: fragsize %lu != blocksize %lu"
1050 "(not supported yet)",
1051 sbi->s_frag_size, sb->s_blocksize);
1052 goto failed_mount;
1053 }
1054
1055 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1056 ext2_msg(sb, KERN_ERR,
1057 "error: #blocks per group too big: %lu",
1058 sbi->s_blocks_per_group);
1059 goto failed_mount;
1060 }
1061 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
1062 ext2_msg(sb, KERN_ERR,
1063 "error: #fragments per group too big: %lu",
1064 sbi->s_frags_per_group);
1065 goto failed_mount;
1066 }
1067 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1068 ext2_msg(sb, KERN_ERR,
1069 "error: #inodes per group too big: %lu",
1070 sbi->s_inodes_per_group);
1071 goto failed_mount;
1072 }
1073
1074 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1075 goto cantfind_ext2;
1076 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1077 le32_to_cpu(es->s_first_data_block) - 1)
1078 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1079 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1080 EXT2_DESC_PER_BLOCK(sb);
1081 sbi->s_group_desc = kmalloc_array (db_count,
1082 sizeof(struct buffer_head *),
1083 GFP_KERNEL);
1084 if (sbi->s_group_desc == NULL) {
1085 ret = -ENOMEM;
1086 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1087 goto failed_mount;
1088 }
1089 bgl_lock_init(sbi->s_blockgroup_lock);
1090 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1091 if (!sbi->s_debts) {
1092 ret = -ENOMEM;
1093 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1094 goto failed_mount_group_desc;
1095 }
1096 for (i = 0; i < db_count; i++) {
1097 block = descriptor_loc(sb, logic_sb_block, i);
1098 sbi->s_group_desc[i] = sb_bread(sb, block);
1099 if (!sbi->s_group_desc[i]) {
1100 for (j = 0; j < i; j++)
1101 brelse (sbi->s_group_desc[j]);
1102 ext2_msg(sb, KERN_ERR,
1103 "error: unable to read group descriptors");
1104 goto failed_mount_group_desc;
1105 }
1106 }
1107 if (!ext2_check_descriptors (sb)) {
1108 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1109 goto failed_mount2;
1110 }
1111 sbi->s_gdb_count = db_count;
1112 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1113 spin_lock_init(&sbi->s_next_gen_lock);
1114
1115 /* per fileystem reservation list head & lock */
1116 spin_lock_init(&sbi->s_rsv_window_lock);
1117 sbi->s_rsv_window_root = RB_ROOT;
1118 /*
1119 * Add a single, static dummy reservation to the start of the
1120 * reservation window list --- it gives us a placeholder for
1121 * append-at-start-of-list which makes the allocation logic
1122 * _much_ simpler.
1123 */
1124 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1125 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1126 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1127 sbi->s_rsv_window_head.rsv_goal_size = 0;
1128 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1129
1130 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1131 ext2_count_free_blocks(sb), GFP_KERNEL);
1132 if (!err) {
1133 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1134 ext2_count_free_inodes(sb), GFP_KERNEL);
1135 }
1136 if (!err) {
1137 err = percpu_counter_init(&sbi->s_dirs_counter,
1138 ext2_count_dirs(sb), GFP_KERNEL);
1139 }
1140 if (err) {
1141 ret = err;
1142 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1143 goto failed_mount3;
1144 }
1145
1146 #ifdef CONFIG_EXT2_FS_XATTR
1147 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1148 if (!sbi->s_ea_block_cache) {
1149 ret = -ENOMEM;
1150 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1151 goto failed_mount3;
1152 }
1153 #endif
1154 /*
1155 * set up enough so that it can read an inode
1156 */
1157 sb->s_op = &ext2_sops;
1158 sb->s_export_op = &ext2_export_ops;
1159 sb->s_xattr = ext2_xattr_handlers;
1160
1161 #ifdef CONFIG_QUOTA
1162 sb->dq_op = &dquot_operations;
1163 sb->s_qcop = &ext2_quotactl_ops;
1164 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1165 #endif
1166
1167 root = ext2_iget(sb, EXT2_ROOT_INO);
1168 if (IS_ERR(root)) {
1169 ret = PTR_ERR(root);
1170 goto failed_mount3;
1171 }
1172 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1173 iput(root);
1174 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1175 goto failed_mount3;
1176 }
1177
1178 sb->s_root = d_make_root(root);
1179 if (!sb->s_root) {
1180 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1181 ret = -ENOMEM;
1182 goto failed_mount3;
1183 }
1184 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1185 ext2_msg(sb, KERN_WARNING,
1186 "warning: mounting ext3 filesystem as ext2");
1187 if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1188 sb->s_flags |= SB_RDONLY;
1189 ext2_write_super(sb);
1190 return 0;
1191
1192 cantfind_ext2:
1193 if (!silent)
1194 ext2_msg(sb, KERN_ERR,
1195 "error: can't find an ext2 filesystem on dev %s.",
1196 sb->s_id);
1197 goto failed_mount;
1198 failed_mount3:
1199 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1200 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1201 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1202 percpu_counter_destroy(&sbi->s_dirs_counter);
1203 failed_mount2:
1204 for (i = 0; i < db_count; i++)
1205 brelse(sbi->s_group_desc[i]);
1206 failed_mount_group_desc:
1207 kfree(sbi->s_group_desc);
1208 kfree(sbi->s_debts);
1209 failed_mount:
1210 brelse(bh);
1211 failed_sbi:
1212 sb->s_fs_info = NULL;
1213 kfree(sbi->s_blockgroup_lock);
1214 kfree(sbi);
1215 failed:
1216 fs_put_dax(dax_dev);
1217 return ret;
1218 }
1219
1220 static void ext2_clear_super_error(struct super_block *sb)
1221 {
1222 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1223
1224 if (buffer_write_io_error(sbh)) {
1225 /*
1226 * Oh, dear. A previous attempt to write the
1227 * superblock failed. This could happen because the
1228 * USB device was yanked out. Or it could happen to
1229 * be a transient write error and maybe the block will
1230 * be remapped. Nothing we can do but to retry the
1231 * write and hope for the best.
1232 */
1233 ext2_msg(sb, KERN_ERR,
1234 "previous I/O error to superblock detected");
1235 clear_buffer_write_io_error(sbh);
1236 set_buffer_uptodate(sbh);
1237 }
1238 }
1239
1240 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1241 int wait)
1242 {
1243 ext2_clear_super_error(sb);
1244 spin_lock(&EXT2_SB(sb)->s_lock);
1245 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1246 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1247 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1248 /* unlock before we do IO */
1249 spin_unlock(&EXT2_SB(sb)->s_lock);
1250 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1251 if (wait)
1252 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1253 }
1254
1255 /*
1256 * In the second extended file system, it is not necessary to
1257 * write the super block since we use a mapping of the
1258 * disk super block in a buffer.
1259 *
1260 * However, this function is still used to set the fs valid
1261 * flags to 0. We need to set this flag to 0 since the fs
1262 * may have been checked while mounted and e2fsck may have
1263 * set s_state to EXT2_VALID_FS after some corrections.
1264 */
1265 static int ext2_sync_fs(struct super_block *sb, int wait)
1266 {
1267 struct ext2_sb_info *sbi = EXT2_SB(sb);
1268 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1269
1270 /*
1271 * Write quota structures to quota file, sync_blockdev() will write
1272 * them to disk later
1273 */
1274 dquot_writeback_dquots(sb, -1);
1275
1276 spin_lock(&sbi->s_lock);
1277 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1278 ext2_debug("setting valid to 0\n");
1279 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1280 }
1281 spin_unlock(&sbi->s_lock);
1282 ext2_sync_super(sb, es, wait);
1283 return 0;
1284 }
1285
1286 static int ext2_freeze(struct super_block *sb)
1287 {
1288 struct ext2_sb_info *sbi = EXT2_SB(sb);
1289
1290 /*
1291 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1292 * because we have unattached inodes and thus filesystem is not fully
1293 * consistent.
1294 */
1295 if (atomic_long_read(&sb->s_remove_count)) {
1296 ext2_sync_fs(sb, 1);
1297 return 0;
1298 }
1299 /* Set EXT2_FS_VALID flag */
1300 spin_lock(&sbi->s_lock);
1301 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1302 spin_unlock(&sbi->s_lock);
1303 ext2_sync_super(sb, sbi->s_es, 1);
1304
1305 return 0;
1306 }
1307
1308 static int ext2_unfreeze(struct super_block *sb)
1309 {
1310 /* Just write sb to clear EXT2_VALID_FS flag */
1311 ext2_write_super(sb);
1312
1313 return 0;
1314 }
1315
1316 static void ext2_write_super(struct super_block *sb)
1317 {
1318 if (!sb_rdonly(sb))
1319 ext2_sync_fs(sb, 1);
1320 }
1321
1322 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1323 {
1324 struct ext2_sb_info * sbi = EXT2_SB(sb);
1325 struct ext2_super_block * es;
1326 struct ext2_mount_options new_opts;
1327 int err;
1328
1329 sync_filesystem(sb);
1330
1331 spin_lock(&sbi->s_lock);
1332 new_opts.s_mount_opt = sbi->s_mount_opt;
1333 new_opts.s_resuid = sbi->s_resuid;
1334 new_opts.s_resgid = sbi->s_resgid;
1335 spin_unlock(&sbi->s_lock);
1336
1337 if (!parse_options(data, sb, &new_opts))
1338 return -EINVAL;
1339
1340 spin_lock(&sbi->s_lock);
1341 es = sbi->s_es;
1342 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1343 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1344 "dax flag with busy inodes while remounting");
1345 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1346 }
1347 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1348 goto out_set;
1349 if (*flags & SB_RDONLY) {
1350 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1351 !(sbi->s_mount_state & EXT2_VALID_FS))
1352 goto out_set;
1353
1354 /*
1355 * OK, we are remounting a valid rw partition rdonly, so set
1356 * the rdonly flag and then mark the partition as valid again.
1357 */
1358 es->s_state = cpu_to_le16(sbi->s_mount_state);
1359 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1360 spin_unlock(&sbi->s_lock);
1361
1362 err = dquot_suspend(sb, -1);
1363 if (err < 0)
1364 return err;
1365
1366 ext2_sync_super(sb, es, 1);
1367 } else {
1368 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1369 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1370 if (ret) {
1371 spin_unlock(&sbi->s_lock);
1372 ext2_msg(sb, KERN_WARNING,
1373 "warning: couldn't remount RDWR because of "
1374 "unsupported optional features (%x).",
1375 le32_to_cpu(ret));
1376 return -EROFS;
1377 }
1378 /*
1379 * Mounting a RDONLY partition read-write, so reread and
1380 * store the current valid flag. (It may have been changed
1381 * by e2fsck since we originally mounted the partition.)
1382 */
1383 sbi->s_mount_state = le16_to_cpu(es->s_state);
1384 if (!ext2_setup_super (sb, es, 0))
1385 sb->s_flags &= ~SB_RDONLY;
1386 spin_unlock(&sbi->s_lock);
1387
1388 ext2_write_super(sb);
1389
1390 dquot_resume(sb, -1);
1391 }
1392
1393 spin_lock(&sbi->s_lock);
1394 out_set:
1395 sbi->s_mount_opt = new_opts.s_mount_opt;
1396 sbi->s_resuid = new_opts.s_resuid;
1397 sbi->s_resgid = new_opts.s_resgid;
1398 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1399 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
1400 spin_unlock(&sbi->s_lock);
1401
1402 return 0;
1403 }
1404
1405 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1406 {
1407 struct super_block *sb = dentry->d_sb;
1408 struct ext2_sb_info *sbi = EXT2_SB(sb);
1409 struct ext2_super_block *es = sbi->s_es;
1410 u64 fsid;
1411
1412 spin_lock(&sbi->s_lock);
1413
1414 if (test_opt (sb, MINIX_DF))
1415 sbi->s_overhead_last = 0;
1416 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1417 unsigned long i, overhead = 0;
1418 smp_rmb();
1419
1420 /*
1421 * Compute the overhead (FS structures). This is constant
1422 * for a given filesystem unless the number of block groups
1423 * changes so we cache the previous value until it does.
1424 */
1425
1426 /*
1427 * All of the blocks before first_data_block are
1428 * overhead
1429 */
1430 overhead = le32_to_cpu(es->s_first_data_block);
1431
1432 /*
1433 * Add the overhead attributed to the superblock and
1434 * block group descriptors. If the sparse superblocks
1435 * feature is turned on, then not all groups have this.
1436 */
1437 for (i = 0; i < sbi->s_groups_count; i++)
1438 overhead += ext2_bg_has_super(sb, i) +
1439 ext2_bg_num_gdb(sb, i);
1440
1441 /*
1442 * Every block group has an inode bitmap, a block
1443 * bitmap, and an inode table.
1444 */
1445 overhead += (sbi->s_groups_count *
1446 (2 + sbi->s_itb_per_group));
1447 sbi->s_overhead_last = overhead;
1448 smp_wmb();
1449 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1450 }
1451
1452 buf->f_type = EXT2_SUPER_MAGIC;
1453 buf->f_bsize = sb->s_blocksize;
1454 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1455 buf->f_bfree = ext2_count_free_blocks(sb);
1456 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1457 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1458 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1459 buf->f_bavail = 0;
1460 buf->f_files = le32_to_cpu(es->s_inodes_count);
1461 buf->f_ffree = ext2_count_free_inodes(sb);
1462 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1463 buf->f_namelen = EXT2_NAME_LEN;
1464 fsid = le64_to_cpup((void *)es->s_uuid) ^
1465 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1466 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1467 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1468 spin_unlock(&sbi->s_lock);
1469 return 0;
1470 }
1471
1472 static struct dentry *ext2_mount(struct file_system_type *fs_type,
1473 int flags, const char *dev_name, void *data)
1474 {
1475 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1476 }
1477
1478 #ifdef CONFIG_QUOTA
1479
1480 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1481 * acquiring the locks... As quota files are never truncated and quota code
1482 * itself serializes the operations (and no one else should touch the files)
1483 * we don't have to be afraid of races */
1484 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1485 size_t len, loff_t off)
1486 {
1487 struct inode *inode = sb_dqopt(sb)->files[type];
1488 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1489 int err = 0;
1490 int offset = off & (sb->s_blocksize - 1);
1491 int tocopy;
1492 size_t toread;
1493 struct buffer_head tmp_bh;
1494 struct buffer_head *bh;
1495 loff_t i_size = i_size_read(inode);
1496
1497 if (off > i_size)
1498 return 0;
1499 if (off+len > i_size)
1500 len = i_size-off;
1501 toread = len;
1502 while (toread > 0) {
1503 tocopy = sb->s_blocksize - offset < toread ?
1504 sb->s_blocksize - offset : toread;
1505
1506 tmp_bh.b_state = 0;
1507 tmp_bh.b_size = sb->s_blocksize;
1508 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1509 if (err < 0)
1510 return err;
1511 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1512 memset(data, 0, tocopy);
1513 else {
1514 bh = sb_bread(sb, tmp_bh.b_blocknr);
1515 if (!bh)
1516 return -EIO;
1517 memcpy(data, bh->b_data+offset, tocopy);
1518 brelse(bh);
1519 }
1520 offset = 0;
1521 toread -= tocopy;
1522 data += tocopy;
1523 blk++;
1524 }
1525 return len;
1526 }
1527
1528 /* Write to quotafile */
1529 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1530 const char *data, size_t len, loff_t off)
1531 {
1532 struct inode *inode = sb_dqopt(sb)->files[type];
1533 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1534 int err = 0;
1535 int offset = off & (sb->s_blocksize - 1);
1536 int tocopy;
1537 size_t towrite = len;
1538 struct buffer_head tmp_bh;
1539 struct buffer_head *bh;
1540
1541 while (towrite > 0) {
1542 tocopy = sb->s_blocksize - offset < towrite ?
1543 sb->s_blocksize - offset : towrite;
1544
1545 tmp_bh.b_state = 0;
1546 tmp_bh.b_size = sb->s_blocksize;
1547 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1548 if (err < 0)
1549 goto out;
1550 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1551 bh = sb_bread(sb, tmp_bh.b_blocknr);
1552 else
1553 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1554 if (unlikely(!bh)) {
1555 err = -EIO;
1556 goto out;
1557 }
1558 lock_buffer(bh);
1559 memcpy(bh->b_data+offset, data, tocopy);
1560 flush_dcache_page(bh->b_page);
1561 set_buffer_uptodate(bh);
1562 mark_buffer_dirty(bh);
1563 unlock_buffer(bh);
1564 brelse(bh);
1565 offset = 0;
1566 towrite -= tocopy;
1567 data += tocopy;
1568 blk++;
1569 }
1570 out:
1571 if (len == towrite)
1572 return err;
1573 if (inode->i_size < off+len-towrite)
1574 i_size_write(inode, off+len-towrite);
1575 inode_inc_iversion(inode);
1576 inode->i_mtime = inode->i_ctime = current_time(inode);
1577 mark_inode_dirty(inode);
1578 return len - towrite;
1579 }
1580
1581 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1582 const struct path *path)
1583 {
1584 int err;
1585 struct inode *inode;
1586
1587 err = dquot_quota_on(sb, type, format_id, path);
1588 if (err)
1589 return err;
1590
1591 inode = d_inode(path->dentry);
1592 inode_lock(inode);
1593 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1594 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1595 S_NOATIME | S_IMMUTABLE);
1596 inode_unlock(inode);
1597 mark_inode_dirty(inode);
1598
1599 return 0;
1600 }
1601
1602 static int ext2_quota_off(struct super_block *sb, int type)
1603 {
1604 struct inode *inode = sb_dqopt(sb)->files[type];
1605 int err;
1606
1607 if (!inode || !igrab(inode))
1608 goto out;
1609
1610 err = dquot_quota_off(sb, type);
1611 if (err)
1612 goto out_put;
1613
1614 inode_lock(inode);
1615 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1616 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1617 inode_unlock(inode);
1618 mark_inode_dirty(inode);
1619 out_put:
1620 iput(inode);
1621 return err;
1622 out:
1623 return dquot_quota_off(sb, type);
1624 }
1625
1626 #endif
1627
1628 static struct file_system_type ext2_fs_type = {
1629 .owner = THIS_MODULE,
1630 .name = "ext2",
1631 .mount = ext2_mount,
1632 .kill_sb = kill_block_super,
1633 .fs_flags = FS_REQUIRES_DEV,
1634 };
1635 MODULE_ALIAS_FS("ext2");
1636
1637 static int __init init_ext2_fs(void)
1638 {
1639 int err;
1640
1641 err = init_inodecache();
1642 if (err)
1643 return err;
1644 err = register_filesystem(&ext2_fs_type);
1645 if (err)
1646 goto out;
1647 return 0;
1648 out:
1649 destroy_inodecache();
1650 return err;
1651 }
1652
1653 static void __exit exit_ext2_fs(void)
1654 {
1655 unregister_filesystem(&ext2_fs_type);
1656 destroy_inodecache();
1657 }
1658
1659 MODULE_AUTHOR("Remy Card and others");
1660 MODULE_DESCRIPTION("Second Extended Filesystem");
1661 MODULE_LICENSE("GPL");
1662 module_init(init_ext2_fs)
1663 module_exit(exit_ext2_fs)
Linux with added FPC-III support