]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - fs/ext2/super.c
projects / mirror_ubuntu-artful-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Merge tag 'for-linus-20151120' of git://git.infradead.org/linux-mtd
[mirror_ubuntu-artful-kernel.git] / fs / ext2 / super.c
1 /*
2 * linux/fs/ext2/super.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/inode.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * Big-endian to little-endian byte-swapping/bitmaps by
16 * David S. Miller (davem@caip.rutgers.edu), 1995
17 */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/slab.h>
23 #include <linux/init.h>
24 #include <linux/blkdev.h>
25 #include <linux/parser.h>
26 #include <linux/random.h>
27 #include <linux/buffer_head.h>
28 #include <linux/exportfs.h>
29 #include <linux/vfs.h>
30 #include <linux/seq_file.h>
31 #include <linux/mount.h>
32 #include <linux/log2.h>
33 #include <linux/quotaops.h>
34 #include <asm/uaccess.h>
35 #include "ext2.h"
36 #include "xattr.h"
37 #include "acl.h"
38
39 static void ext2_sync_super(struct super_block *sb,
40 struct ext2_super_block *es, int wait);
41 static int ext2_remount (struct super_block * sb, int * flags, char * data);
42 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
43 static int ext2_sync_fs(struct super_block *sb, int wait);
44 static int ext2_freeze(struct super_block *sb);
45 static int ext2_unfreeze(struct super_block *sb);
46
47 void ext2_error(struct super_block *sb, const char *function,
48 const char *fmt, ...)
49 {
50 struct va_format vaf;
51 va_list args;
52 struct ext2_sb_info *sbi = EXT2_SB(sb);
53 struct ext2_super_block *es = sbi->s_es;
54
55 if (!(sb->s_flags & MS_RDONLY)) {
56 spin_lock(&sbi->s_lock);
57 sbi->s_mount_state |= EXT2_ERROR_FS;
58 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
59 spin_unlock(&sbi->s_lock);
60 ext2_sync_super(sb, es, 1);
61 }
62
63 va_start(args, fmt);
64
65 vaf.fmt = fmt;
66 vaf.va = &args;
67
68 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
69 sb->s_id, function, &vaf);
70
71 va_end(args);
72
73 if (test_opt(sb, ERRORS_PANIC))
74 panic("EXT2-fs: panic from previous error\n");
75 if (test_opt(sb, ERRORS_RO)) {
76 ext2_msg(sb, KERN_CRIT,
77 "error: remounting filesystem read-only");
78 sb->s_flags |= MS_RDONLY;
79 }
80 }
81
82 void ext2_msg(struct super_block *sb, const char *prefix,
83 const char *fmt, ...)
84 {
85 struct va_format vaf;
86 va_list args;
87
88 va_start(args, fmt);
89
90 vaf.fmt = fmt;
91 vaf.va = &args;
92
93 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
94
95 va_end(args);
96 }
97
98 /*
99 * This must be called with sbi->s_lock held.
100 */
101 void ext2_update_dynamic_rev(struct super_block *sb)
102 {
103 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
104
105 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
106 return;
107
108 ext2_msg(sb, KERN_WARNING,
109 "warning: updating to rev %d because of "
110 "new feature flag, running e2fsck is recommended",
111 EXT2_DYNAMIC_REV);
112
113 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
114 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
115 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
116 /* leave es->s_feature_*compat flags alone */
117 /* es->s_uuid will be set by e2fsck if empty */
118
119 /*
120 * The rest of the superblock fields should be zero, and if not it
121 * means they are likely already in use, so leave them alone. We
122 * can leave it up to e2fsck to clean up any inconsistencies there.
123 */
124 }
125
126 static void ext2_put_super (struct super_block * sb)
127 {
128 int db_count;
129 int i;
130 struct ext2_sb_info *sbi = EXT2_SB(sb);
131
132 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
133
134 ext2_xattr_put_super(sb);
135 if (!(sb->s_flags & MS_RDONLY)) {
136 struct ext2_super_block *es = sbi->s_es;
137
138 spin_lock(&sbi->s_lock);
139 es->s_state = cpu_to_le16(sbi->s_mount_state);
140 spin_unlock(&sbi->s_lock);
141 ext2_sync_super(sb, es, 1);
142 }
143 db_count = sbi->s_gdb_count;
144 for (i = 0; i < db_count; i++)
145 if (sbi->s_group_desc[i])
146 brelse (sbi->s_group_desc[i]);
147 kfree(sbi->s_group_desc);
148 kfree(sbi->s_debts);
149 percpu_counter_destroy(&sbi->s_freeblocks_counter);
150 percpu_counter_destroy(&sbi->s_freeinodes_counter);
151 percpu_counter_destroy(&sbi->s_dirs_counter);
152 brelse (sbi->s_sbh);
153 sb->s_fs_info = NULL;
154 kfree(sbi->s_blockgroup_lock);
155 kfree(sbi);
156 }
157
158 static struct kmem_cache * ext2_inode_cachep;
159
160 static struct inode *ext2_alloc_inode(struct super_block *sb)
161 {
162 struct ext2_inode_info *ei;
163 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
164 if (!ei)
165 return NULL;
166 ei->i_block_alloc_info = NULL;
167 ei->vfs_inode.i_version = 1;
168 #ifdef CONFIG_QUOTA
169 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
170 #endif
171
172 return &ei->vfs_inode;
173 }
174
175 static void ext2_i_callback(struct rcu_head *head)
176 {
177 struct inode *inode = container_of(head, struct inode, i_rcu);
178 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
179 }
180
181 static void ext2_destroy_inode(struct inode *inode)
182 {
183 call_rcu(&inode->i_rcu, ext2_i_callback);
184 }
185
186 static void init_once(void *foo)
187 {
188 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
189
190 rwlock_init(&ei->i_meta_lock);
191 #ifdef CONFIG_EXT2_FS_XATTR
192 init_rwsem(&ei->xattr_sem);
193 #endif
194 mutex_init(&ei->truncate_mutex);
195 #ifdef CONFIG_FS_DAX
196 init_rwsem(&ei->dax_sem);
197 #endif
198 inode_init_once(&ei->vfs_inode);
199 }
200
201 static int __init init_inodecache(void)
202 {
203 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
204 sizeof(struct ext2_inode_info),
205 0, (SLAB_RECLAIM_ACCOUNT|
206 SLAB_MEM_SPREAD),
207 init_once);
208 if (ext2_inode_cachep == NULL)
209 return -ENOMEM;
210 return 0;
211 }
212
213 static void destroy_inodecache(void)
214 {
215 /*
216 * Make sure all delayed rcu free inodes are flushed before we
217 * destroy cache.
218 */
219 rcu_barrier();
220 kmem_cache_destroy(ext2_inode_cachep);
221 }
222
223 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
224 {
225 struct super_block *sb = root->d_sb;
226 struct ext2_sb_info *sbi = EXT2_SB(sb);
227 struct ext2_super_block *es = sbi->s_es;
228 unsigned long def_mount_opts;
229
230 spin_lock(&sbi->s_lock);
231 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
232
233 if (sbi->s_sb_block != 1)
234 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
235 if (test_opt(sb, MINIX_DF))
236 seq_puts(seq, ",minixdf");
237 if (test_opt(sb, GRPID))
238 seq_puts(seq, ",grpid");
239 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
240 seq_puts(seq, ",nogrpid");
241 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
242 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
243 seq_printf(seq, ",resuid=%u",
244 from_kuid_munged(&init_user_ns, sbi->s_resuid));
245 }
246 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
247 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
248 seq_printf(seq, ",resgid=%u",
249 from_kgid_munged(&init_user_ns, sbi->s_resgid));
250 }
251 if (test_opt(sb, ERRORS_RO)) {
252 int def_errors = le16_to_cpu(es->s_errors);
253
254 if (def_errors == EXT2_ERRORS_PANIC ||
255 def_errors == EXT2_ERRORS_CONTINUE) {
256 seq_puts(seq, ",errors=remount-ro");
257 }
258 }
259 if (test_opt(sb, ERRORS_CONT))
260 seq_puts(seq, ",errors=continue");
261 if (test_opt(sb, ERRORS_PANIC))
262 seq_puts(seq, ",errors=panic");
263 if (test_opt(sb, NO_UID32))
264 seq_puts(seq, ",nouid32");
265 if (test_opt(sb, DEBUG))
266 seq_puts(seq, ",debug");
267 if (test_opt(sb, OLDALLOC))
268 seq_puts(seq, ",oldalloc");
269
270 #ifdef CONFIG_EXT2_FS_XATTR
271 if (test_opt(sb, XATTR_USER))
272 seq_puts(seq, ",user_xattr");
273 if (!test_opt(sb, XATTR_USER) &&
274 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
275 seq_puts(seq, ",nouser_xattr");
276 }
277 #endif
278
279 #ifdef CONFIG_EXT2_FS_POSIX_ACL
280 if (test_opt(sb, POSIX_ACL))
281 seq_puts(seq, ",acl");
282 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
283 seq_puts(seq, ",noacl");
284 #endif
285
286 if (test_opt(sb, NOBH))
287 seq_puts(seq, ",nobh");
288
289 #if defined(CONFIG_QUOTA)
290 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
291 seq_puts(seq, ",usrquota");
292
293 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
294 seq_puts(seq, ",grpquota");
295 #endif
296
297 #ifdef CONFIG_FS_DAX
298 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
299 seq_puts(seq, ",xip");
300 if (sbi->s_mount_opt & EXT2_MOUNT_DAX)
301 seq_puts(seq, ",dax");
302 #endif
303
304 if (!test_opt(sb, RESERVATION))
305 seq_puts(seq, ",noreservation");
306
307 spin_unlock(&sbi->s_lock);
308 return 0;
309 }
310
311 #ifdef CONFIG_QUOTA
312 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
313 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
314 static struct dquot **ext2_get_dquots(struct inode *inode)
315 {
316 return EXT2_I(inode)->i_dquot;
317 }
318 #endif
319
320 static const struct super_operations ext2_sops = {
321 .alloc_inode = ext2_alloc_inode,
322 .destroy_inode = ext2_destroy_inode,
323 .write_inode = ext2_write_inode,
324 .evict_inode = ext2_evict_inode,
325 .put_super = ext2_put_super,
326 .sync_fs = ext2_sync_fs,
327 .freeze_fs = ext2_freeze,
328 .unfreeze_fs = ext2_unfreeze,
329 .statfs = ext2_statfs,
330 .remount_fs = ext2_remount,
331 .show_options = ext2_show_options,
332 #ifdef CONFIG_QUOTA
333 .quota_read = ext2_quota_read,
334 .quota_write = ext2_quota_write,
335 .get_dquots = ext2_get_dquots,
336 #endif
337 };
338
339 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
340 u64 ino, u32 generation)
341 {
342 struct inode *inode;
343
344 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
345 return ERR_PTR(-ESTALE);
346 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
347 return ERR_PTR(-ESTALE);
348
349 /*
350 * ext2_iget isn't quite right if the inode is currently unallocated!
351 * However ext2_iget currently does appropriate checks to handle stale
352 * inodes so everything is OK.
353 */
354 inode = ext2_iget(sb, ino);
355 if (IS_ERR(inode))
356 return ERR_CAST(inode);
357 if (generation && inode->i_generation != generation) {
358 /* we didn't find the right inode.. */
359 iput(inode);
360 return ERR_PTR(-ESTALE);
361 }
362 return inode;
363 }
364
365 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
366 int fh_len, int fh_type)
367 {
368 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
369 ext2_nfs_get_inode);
370 }
371
372 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
373 int fh_len, int fh_type)
374 {
375 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
376 ext2_nfs_get_inode);
377 }
378
379 static const struct export_operations ext2_export_ops = {
380 .fh_to_dentry = ext2_fh_to_dentry,
381 .fh_to_parent = ext2_fh_to_parent,
382 .get_parent = ext2_get_parent,
383 };
384
385 static unsigned long get_sb_block(void **data)
386 {
387 unsigned long sb_block;
388 char *options = (char *) *data;
389
390 if (!options || strncmp(options, "sb=", 3) != 0)
391 return 1; /* Default location */
392 options += 3;
393 sb_block = simple_strtoul(options, &options, 0);
394 if (*options && *options != ',') {
395 printk("EXT2-fs: Invalid sb specification: %s\n",
396 (char *) *data);
397 return 1;
398 }
399 if (*options == ',')
400 options++;
401 *data = (void *) options;
402 return sb_block;
403 }
404
405 enum {
406 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
407 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
408 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
409 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
410 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
411 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
412 };
413
414 static const match_table_t tokens = {
415 {Opt_bsd_df, "bsddf"},
416 {Opt_minix_df, "minixdf"},
417 {Opt_grpid, "grpid"},
418 {Opt_grpid, "bsdgroups"},
419 {Opt_nogrpid, "nogrpid"},
420 {Opt_nogrpid, "sysvgroups"},
421 {Opt_resgid, "resgid=%u"},
422 {Opt_resuid, "resuid=%u"},
423 {Opt_sb, "sb=%u"},
424 {Opt_err_cont, "errors=continue"},
425 {Opt_err_panic, "errors=panic"},
426 {Opt_err_ro, "errors=remount-ro"},
427 {Opt_nouid32, "nouid32"},
428 {Opt_nocheck, "check=none"},
429 {Opt_nocheck, "nocheck"},
430 {Opt_debug, "debug"},
431 {Opt_oldalloc, "oldalloc"},
432 {Opt_orlov, "orlov"},
433 {Opt_nobh, "nobh"},
434 {Opt_user_xattr, "user_xattr"},
435 {Opt_nouser_xattr, "nouser_xattr"},
436 {Opt_acl, "acl"},
437 {Opt_noacl, "noacl"},
438 {Opt_xip, "xip"},
439 {Opt_dax, "dax"},
440 {Opt_grpquota, "grpquota"},
441 {Opt_ignore, "noquota"},
442 {Opt_quota, "quota"},
443 {Opt_usrquota, "usrquota"},
444 {Opt_reservation, "reservation"},
445 {Opt_noreservation, "noreservation"},
446 {Opt_err, NULL}
447 };
448
449 static int parse_options(char *options, struct super_block *sb)
450 {
451 char *p;
452 struct ext2_sb_info *sbi = EXT2_SB(sb);
453 substring_t args[MAX_OPT_ARGS];
454 int option;
455 kuid_t uid;
456 kgid_t gid;
457
458 if (!options)
459 return 1;
460
461 while ((p = strsep (&options, ",")) != NULL) {
462 int token;
463 if (!*p)
464 continue;
465
466 token = match_token(p, tokens, args);
467 switch (token) {
468 case Opt_bsd_df:
469 clear_opt (sbi->s_mount_opt, MINIX_DF);
470 break;
471 case Opt_minix_df:
472 set_opt (sbi->s_mount_opt, MINIX_DF);
473 break;
474 case Opt_grpid:
475 set_opt (sbi->s_mount_opt, GRPID);
476 break;
477 case Opt_nogrpid:
478 clear_opt (sbi->s_mount_opt, GRPID);
479 break;
480 case Opt_resuid:
481 if (match_int(&args[0], &option))
482 return 0;
483 uid = make_kuid(current_user_ns(), option);
484 if (!uid_valid(uid)) {
485 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
486 return 0;
487
488 }
489 sbi->s_resuid = uid;
490 break;
491 case Opt_resgid:
492 if (match_int(&args[0], &option))
493 return 0;
494 gid = make_kgid(current_user_ns(), option);
495 if (!gid_valid(gid)) {
496 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
497 return 0;
498 }
499 sbi->s_resgid = gid;
500 break;
501 case Opt_sb:
502 /* handled by get_sb_block() instead of here */
503 /* *sb_block = match_int(&args[0]); */
504 break;
505 case Opt_err_panic:
506 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
507 clear_opt (sbi->s_mount_opt, ERRORS_RO);
508 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
509 break;
510 case Opt_err_ro:
511 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
512 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
513 set_opt (sbi->s_mount_opt, ERRORS_RO);
514 break;
515 case Opt_err_cont:
516 clear_opt (sbi->s_mount_opt, ERRORS_RO);
517 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
518 set_opt (sbi->s_mount_opt, ERRORS_CONT);
519 break;
520 case Opt_nouid32:
521 set_opt (sbi->s_mount_opt, NO_UID32);
522 break;
523 case Opt_nocheck:
524 clear_opt (sbi->s_mount_opt, CHECK);
525 break;
526 case Opt_debug:
527 set_opt (sbi->s_mount_opt, DEBUG);
528 break;
529 case Opt_oldalloc:
530 set_opt (sbi->s_mount_opt, OLDALLOC);
531 break;
532 case Opt_orlov:
533 clear_opt (sbi->s_mount_opt, OLDALLOC);
534 break;
535 case Opt_nobh:
536 set_opt (sbi->s_mount_opt, NOBH);
537 break;
538 #ifdef CONFIG_EXT2_FS_XATTR
539 case Opt_user_xattr:
540 set_opt (sbi->s_mount_opt, XATTR_USER);
541 break;
542 case Opt_nouser_xattr:
543 clear_opt (sbi->s_mount_opt, XATTR_USER);
544 break;
545 #else
546 case Opt_user_xattr:
547 case Opt_nouser_xattr:
548 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
549 "not supported");
550 break;
551 #endif
552 #ifdef CONFIG_EXT2_FS_POSIX_ACL
553 case Opt_acl:
554 set_opt(sbi->s_mount_opt, POSIX_ACL);
555 break;
556 case Opt_noacl:
557 clear_opt(sbi->s_mount_opt, POSIX_ACL);
558 break;
559 #else
560 case Opt_acl:
561 case Opt_noacl:
562 ext2_msg(sb, KERN_INFO,
563 "(no)acl options not supported");
564 break;
565 #endif
566 case Opt_xip:
567 ext2_msg(sb, KERN_INFO, "use dax instead of xip");
568 set_opt(sbi->s_mount_opt, XIP);
569 /* Fall through */
570 case Opt_dax:
571 #ifdef CONFIG_FS_DAX
572 ext2_msg(sb, KERN_WARNING,
573 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
574 set_opt(sbi->s_mount_opt, DAX);
575 #else
576 ext2_msg(sb, KERN_INFO, "dax option not supported");
577 #endif
578 break;
579
580 #if defined(CONFIG_QUOTA)
581 case Opt_quota:
582 case Opt_usrquota:
583 set_opt(sbi->s_mount_opt, USRQUOTA);
584 break;
585
586 case Opt_grpquota:
587 set_opt(sbi->s_mount_opt, GRPQUOTA);
588 break;
589 #else
590 case Opt_quota:
591 case Opt_usrquota:
592 case Opt_grpquota:
593 ext2_msg(sb, KERN_INFO,
594 "quota operations not supported");
595 break;
596 #endif
597
598 case Opt_reservation:
599 set_opt(sbi->s_mount_opt, RESERVATION);
600 ext2_msg(sb, KERN_INFO, "reservations ON");
601 break;
602 case Opt_noreservation:
603 clear_opt(sbi->s_mount_opt, RESERVATION);
604 ext2_msg(sb, KERN_INFO, "reservations OFF");
605 break;
606 case Opt_ignore:
607 break;
608 default:
609 return 0;
610 }
611 }
612 return 1;
613 }
614
615 static int ext2_setup_super (struct super_block * sb,
616 struct ext2_super_block * es,
617 int read_only)
618 {
619 int res = 0;
620 struct ext2_sb_info *sbi = EXT2_SB(sb);
621
622 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
623 ext2_msg(sb, KERN_ERR,
624 "error: revision level too high, "
625 "forcing read-only mode");
626 res = MS_RDONLY;
627 }
628 if (read_only)
629 return res;
630 if (!(sbi->s_mount_state & EXT2_VALID_FS))
631 ext2_msg(sb, KERN_WARNING,
632 "warning: mounting unchecked fs, "
633 "running e2fsck is recommended");
634 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
635 ext2_msg(sb, KERN_WARNING,
636 "warning: mounting fs with errors, "
637 "running e2fsck is recommended");
638 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
639 le16_to_cpu(es->s_mnt_count) >=
640 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
641 ext2_msg(sb, KERN_WARNING,
642 "warning: maximal mount count reached, "
643 "running e2fsck is recommended");
644 else if (le32_to_cpu(es->s_checkinterval) &&
645 (le32_to_cpu(es->s_lastcheck) +
646 le32_to_cpu(es->s_checkinterval) <= get_seconds()))
647 ext2_msg(sb, KERN_WARNING,
648 "warning: checktime reached, "
649 "running e2fsck is recommended");
650 if (!le16_to_cpu(es->s_max_mnt_count))
651 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
652 le16_add_cpu(&es->s_mnt_count, 1);
653 if (test_opt (sb, DEBUG))
654 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
655 "bpg=%lu, ipg=%lu, mo=%04lx]",
656 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
657 sbi->s_frag_size,
658 sbi->s_groups_count,
659 EXT2_BLOCKS_PER_GROUP(sb),
660 EXT2_INODES_PER_GROUP(sb),
661 sbi->s_mount_opt);
662 return res;
663 }
664
665 static int ext2_check_descriptors(struct super_block *sb)
666 {
667 int i;
668 struct ext2_sb_info *sbi = EXT2_SB(sb);
669
670 ext2_debug ("Checking group descriptors");
671
672 for (i = 0; i < sbi->s_groups_count; i++) {
673 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
674 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
675 ext2_fsblk_t last_block;
676
677 if (i == sbi->s_groups_count - 1)
678 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
679 else
680 last_block = first_block +
681 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
682
683 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
684 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
685 {
686 ext2_error (sb, "ext2_check_descriptors",
687 "Block bitmap for group %d"
688 " not in group (block %lu)!",
689 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
690 return 0;
691 }
692 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
693 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
694 {
695 ext2_error (sb, "ext2_check_descriptors",
696 "Inode bitmap for group %d"
697 " not in group (block %lu)!",
698 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
699 return 0;
700 }
701 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
702 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
703 last_block)
704 {
705 ext2_error (sb, "ext2_check_descriptors",
706 "Inode table for group %d"
707 " not in group (block %lu)!",
708 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
709 return 0;
710 }
711 }
712 return 1;
713 }
714
715 /*
716 * Maximal file size. There is a direct, and {,double-,triple-}indirect
717 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
718 * We need to be 1 filesystem block less than the 2^32 sector limit.
719 */
720 static loff_t ext2_max_size(int bits)
721 {
722 loff_t res = EXT2_NDIR_BLOCKS;
723 int meta_blocks;
724 loff_t upper_limit;
725
726 /* This is calculated to be the largest file size for a
727 * dense, file such that the total number of
728 * sectors in the file, including data and all indirect blocks,
729 * does not exceed 2^32 -1
730 * __u32 i_blocks representing the total number of
731 * 512 bytes blocks of the file
732 */
733 upper_limit = (1LL << 32) - 1;
734
735 /* total blocks in file system block size */
736 upper_limit >>= (bits - 9);
737
738
739 /* indirect blocks */
740 meta_blocks = 1;
741 /* double indirect blocks */
742 meta_blocks += 1 + (1LL << (bits-2));
743 /* tripple indirect blocks */
744 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
745
746 upper_limit -= meta_blocks;
747 upper_limit <<= bits;
748
749 res += 1LL << (bits-2);
750 res += 1LL << (2*(bits-2));
751 res += 1LL << (3*(bits-2));
752 res <<= bits;
753 if (res > upper_limit)
754 res = upper_limit;
755
756 if (res > MAX_LFS_FILESIZE)
757 res = MAX_LFS_FILESIZE;
758
759 return res;
760 }
761
762 static unsigned long descriptor_loc(struct super_block *sb,
763 unsigned long logic_sb_block,
764 int nr)
765 {
766 struct ext2_sb_info *sbi = EXT2_SB(sb);
767 unsigned long bg, first_meta_bg;
768 int has_super = 0;
769
770 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
771
772 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
773 nr < first_meta_bg)
774 return (logic_sb_block + nr + 1);
775 bg = sbi->s_desc_per_block * nr;
776 if (ext2_bg_has_super(sb, bg))
777 has_super = 1;
778
779 return ext2_group_first_block_no(sb, bg) + has_super;
780 }
781
782 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
783 {
784 struct buffer_head * bh;
785 struct ext2_sb_info * sbi;
786 struct ext2_super_block * es;
787 struct inode *root;
788 unsigned long block;
789 unsigned long sb_block = get_sb_block(&data);
790 unsigned long logic_sb_block;
791 unsigned long offset = 0;
792 unsigned long def_mount_opts;
793 long ret = -EINVAL;
794 int blocksize = BLOCK_SIZE;
795 int db_count;
796 int i, j;
797 __le32 features;
798 int err;
799
800 err = -ENOMEM;
801 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
802 if (!sbi)
803 goto failed;
804
805 sbi->s_blockgroup_lock =
806 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
807 if (!sbi->s_blockgroup_lock) {
808 kfree(sbi);
809 goto failed;
810 }
811 sb->s_fs_info = sbi;
812 sbi->s_sb_block = sb_block;
813
814 spin_lock_init(&sbi->s_lock);
815
816 /*
817 * See what the current blocksize for the device is, and
818 * use that as the blocksize. Otherwise (or if the blocksize
819 * is smaller than the default) use the default.
820 * This is important for devices that have a hardware
821 * sectorsize that is larger than the default.
822 */
823 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
824 if (!blocksize) {
825 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
826 goto failed_sbi;
827 }
828
829 /*
830 * If the superblock doesn't start on a hardware sector boundary,
831 * calculate the offset.
832 */
833 if (blocksize != BLOCK_SIZE) {
834 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
835 offset = (sb_block*BLOCK_SIZE) % blocksize;
836 } else {
837 logic_sb_block = sb_block;
838 }
839
840 if (!(bh = sb_bread(sb, logic_sb_block))) {
841 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
842 goto failed_sbi;
843 }
844 /*
845 * Note: s_es must be initialized as soon as possible because
846 * some ext2 macro-instructions depend on its value
847 */
848 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
849 sbi->s_es = es;
850 sb->s_magic = le16_to_cpu(es->s_magic);
851
852 if (sb->s_magic != EXT2_SUPER_MAGIC)
853 goto cantfind_ext2;
854
855 /* Set defaults before we parse the mount options */
856 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
857 if (def_mount_opts & EXT2_DEFM_DEBUG)
858 set_opt(sbi->s_mount_opt, DEBUG);
859 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
860 set_opt(sbi->s_mount_opt, GRPID);
861 if (def_mount_opts & EXT2_DEFM_UID16)
862 set_opt(sbi->s_mount_opt, NO_UID32);
863 #ifdef CONFIG_EXT2_FS_XATTR
864 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
865 set_opt(sbi->s_mount_opt, XATTR_USER);
866 #endif
867 #ifdef CONFIG_EXT2_FS_POSIX_ACL
868 if (def_mount_opts & EXT2_DEFM_ACL)
869 set_opt(sbi->s_mount_opt, POSIX_ACL);
870 #endif
871
872 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
873 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
874 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
875 set_opt(sbi->s_mount_opt, ERRORS_CONT);
876 else
877 set_opt(sbi->s_mount_opt, ERRORS_RO);
878
879 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
880 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
881
882 set_opt(sbi->s_mount_opt, RESERVATION);
883
884 if (!parse_options((char *) data, sb))
885 goto failed_mount;
886
887 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
888 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
889 MS_POSIXACL : 0);
890 sb->s_iflags |= SB_I_CGROUPWB;
891
892 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
893 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
894 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
895 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
896 ext2_msg(sb, KERN_WARNING,
897 "warning: feature flags set on rev 0 fs, "
898 "running e2fsck is recommended");
899 /*
900 * Check feature flags regardless of the revision level, since we
901 * previously didn't change the revision level when setting the flags,
902 * so there is a chance incompat flags are set on a rev 0 filesystem.
903 */
904 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
905 if (features) {
906 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
907 "unsupported optional features (%x)",
908 le32_to_cpu(features));
909 goto failed_mount;
910 }
911 if (!(sb->s_flags & MS_RDONLY) &&
912 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
913 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
914 "unsupported optional features (%x)",
915 le32_to_cpu(features));
916 goto failed_mount;
917 }
918
919 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
920
921 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
922 if (blocksize != PAGE_SIZE) {
923 ext2_msg(sb, KERN_ERR,
924 "error: unsupported blocksize for dax");
925 goto failed_mount;
926 }
927 if (!sb->s_bdev->bd_disk->fops->direct_access) {
928 ext2_msg(sb, KERN_ERR,
929 "error: device does not support dax");
930 goto failed_mount;
931 }
932 }
933
934 /* If the blocksize doesn't match, re-read the thing.. */
935 if (sb->s_blocksize != blocksize) {
936 brelse(bh);
937
938 if (!sb_set_blocksize(sb, blocksize)) {
939 ext2_msg(sb, KERN_ERR,
940 "error: bad blocksize %d", blocksize);
941 goto failed_sbi;
942 }
943
944 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
945 offset = (sb_block*BLOCK_SIZE) % blocksize;
946 bh = sb_bread(sb, logic_sb_block);
947 if(!bh) {
948 ext2_msg(sb, KERN_ERR, "error: couldn't read"
949 "superblock on 2nd try");
950 goto failed_sbi;
951 }
952 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
953 sbi->s_es = es;
954 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
955 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
956 goto failed_mount;
957 }
958 }
959
960 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
961 sb->s_max_links = EXT2_LINK_MAX;
962
963 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
964 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
965 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
966 } else {
967 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
968 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
969 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
970 !is_power_of_2(sbi->s_inode_size) ||
971 (sbi->s_inode_size > blocksize)) {
972 ext2_msg(sb, KERN_ERR,
973 "error: unsupported inode size: %d",
974 sbi->s_inode_size);
975 goto failed_mount;
976 }
977 }
978
979 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
980 le32_to_cpu(es->s_log_frag_size);
981 if (sbi->s_frag_size == 0)
982 goto cantfind_ext2;
983 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
984
985 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
986 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
987 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
988
989 if (EXT2_INODE_SIZE(sb) == 0)
990 goto cantfind_ext2;
991 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
992 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
993 goto cantfind_ext2;
994 sbi->s_itb_per_group = sbi->s_inodes_per_group /
995 sbi->s_inodes_per_block;
996 sbi->s_desc_per_block = sb->s_blocksize /
997 sizeof (struct ext2_group_desc);
998 sbi->s_sbh = bh;
999 sbi->s_mount_state = le16_to_cpu(es->s_state);
1000 sbi->s_addr_per_block_bits =
1001 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1002 sbi->s_desc_per_block_bits =
1003 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1004
1005 if (sb->s_magic != EXT2_SUPER_MAGIC)
1006 goto cantfind_ext2;
1007
1008 if (sb->s_blocksize != bh->b_size) {
1009 if (!silent)
1010 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1011 goto failed_mount;
1012 }
1013
1014 if (sb->s_blocksize != sbi->s_frag_size) {
1015 ext2_msg(sb, KERN_ERR,
1016 "error: fragsize %lu != blocksize %lu"
1017 "(not supported yet)",
1018 sbi->s_frag_size, sb->s_blocksize);
1019 goto failed_mount;
1020 }
1021
1022 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1023 ext2_msg(sb, KERN_ERR,
1024 "error: #blocks per group too big: %lu",
1025 sbi->s_blocks_per_group);
1026 goto failed_mount;
1027 }
1028 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
1029 ext2_msg(sb, KERN_ERR,
1030 "error: #fragments per group too big: %lu",
1031 sbi->s_frags_per_group);
1032 goto failed_mount;
1033 }
1034 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1035 ext2_msg(sb, KERN_ERR,
1036 "error: #inodes per group too big: %lu",
1037 sbi->s_inodes_per_group);
1038 goto failed_mount;
1039 }
1040
1041 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1042 goto cantfind_ext2;
1043 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1044 le32_to_cpu(es->s_first_data_block) - 1)
1045 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1046 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1047 EXT2_DESC_PER_BLOCK(sb);
1048 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
1049 if (sbi->s_group_desc == NULL) {
1050 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1051 goto failed_mount;
1052 }
1053 bgl_lock_init(sbi->s_blockgroup_lock);
1054 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1055 if (!sbi->s_debts) {
1056 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1057 goto failed_mount_group_desc;
1058 }
1059 for (i = 0; i < db_count; i++) {
1060 block = descriptor_loc(sb, logic_sb_block, i);
1061 sbi->s_group_desc[i] = sb_bread(sb, block);
1062 if (!sbi->s_group_desc[i]) {
1063 for (j = 0; j < i; j++)
1064 brelse (sbi->s_group_desc[j]);
1065 ext2_msg(sb, KERN_ERR,
1066 "error: unable to read group descriptors");
1067 goto failed_mount_group_desc;
1068 }
1069 }
1070 if (!ext2_check_descriptors (sb)) {
1071 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1072 goto failed_mount2;
1073 }
1074 sbi->s_gdb_count = db_count;
1075 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1076 spin_lock_init(&sbi->s_next_gen_lock);
1077
1078 /* per fileystem reservation list head & lock */
1079 spin_lock_init(&sbi->s_rsv_window_lock);
1080 sbi->s_rsv_window_root = RB_ROOT;
1081 /*
1082 * Add a single, static dummy reservation to the start of the
1083 * reservation window list --- it gives us a placeholder for
1084 * append-at-start-of-list which makes the allocation logic
1085 * _much_ simpler.
1086 */
1087 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1088 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1089 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1090 sbi->s_rsv_window_head.rsv_goal_size = 0;
1091 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1092
1093 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1094 ext2_count_free_blocks(sb), GFP_KERNEL);
1095 if (!err) {
1096 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1097 ext2_count_free_inodes(sb), GFP_KERNEL);
1098 }
1099 if (!err) {
1100 err = percpu_counter_init(&sbi->s_dirs_counter,
1101 ext2_count_dirs(sb), GFP_KERNEL);
1102 }
1103 if (err) {
1104 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1105 goto failed_mount3;
1106 }
1107 /*
1108 * set up enough so that it can read an inode
1109 */
1110 sb->s_op = &ext2_sops;
1111 sb->s_export_op = &ext2_export_ops;
1112 sb->s_xattr = ext2_xattr_handlers;
1113
1114 #ifdef CONFIG_QUOTA
1115 sb->dq_op = &dquot_operations;
1116 sb->s_qcop = &dquot_quotactl_ops;
1117 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1118 #endif
1119
1120 root = ext2_iget(sb, EXT2_ROOT_INO);
1121 if (IS_ERR(root)) {
1122 ret = PTR_ERR(root);
1123 goto failed_mount3;
1124 }
1125 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1126 iput(root);
1127 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1128 goto failed_mount3;
1129 }
1130
1131 sb->s_root = d_make_root(root);
1132 if (!sb->s_root) {
1133 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1134 ret = -ENOMEM;
1135 goto failed_mount3;
1136 }
1137 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1138 ext2_msg(sb, KERN_WARNING,
1139 "warning: mounting ext3 filesystem as ext2");
1140 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY))
1141 sb->s_flags |= MS_RDONLY;
1142 ext2_write_super(sb);
1143 return 0;
1144
1145 cantfind_ext2:
1146 if (!silent)
1147 ext2_msg(sb, KERN_ERR,
1148 "error: can't find an ext2 filesystem on dev %s.",
1149 sb->s_id);
1150 goto failed_mount;
1151 failed_mount3:
1152 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1153 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1154 percpu_counter_destroy(&sbi->s_dirs_counter);
1155 failed_mount2:
1156 for (i = 0; i < db_count; i++)
1157 brelse(sbi->s_group_desc[i]);
1158 failed_mount_group_desc:
1159 kfree(sbi->s_group_desc);
1160 kfree(sbi->s_debts);
1161 failed_mount:
1162 brelse(bh);
1163 failed_sbi:
1164 sb->s_fs_info = NULL;
1165 kfree(sbi->s_blockgroup_lock);
1166 kfree(sbi);
1167 failed:
1168 return ret;
1169 }
1170
1171 static void ext2_clear_super_error(struct super_block *sb)
1172 {
1173 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1174
1175 if (buffer_write_io_error(sbh)) {
1176 /*
1177 * Oh, dear. A previous attempt to write the
1178 * superblock failed. This could happen because the
1179 * USB device was yanked out. Or it could happen to
1180 * be a transient write error and maybe the block will
1181 * be remapped. Nothing we can do but to retry the
1182 * write and hope for the best.
1183 */
1184 ext2_msg(sb, KERN_ERR,
1185 "previous I/O error to superblock detected\n");
1186 clear_buffer_write_io_error(sbh);
1187 set_buffer_uptodate(sbh);
1188 }
1189 }
1190
1191 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1192 int wait)
1193 {
1194 ext2_clear_super_error(sb);
1195 spin_lock(&EXT2_SB(sb)->s_lock);
1196 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1197 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1198 es->s_wtime = cpu_to_le32(get_seconds());
1199 /* unlock before we do IO */
1200 spin_unlock(&EXT2_SB(sb)->s_lock);
1201 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1202 if (wait)
1203 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1204 }
1205
1206 /*
1207 * In the second extended file system, it is not necessary to
1208 * write the super block since we use a mapping of the
1209 * disk super block in a buffer.
1210 *
1211 * However, this function is still used to set the fs valid
1212 * flags to 0. We need to set this flag to 0 since the fs
1213 * may have been checked while mounted and e2fsck may have
1214 * set s_state to EXT2_VALID_FS after some corrections.
1215 */
1216 static int ext2_sync_fs(struct super_block *sb, int wait)
1217 {
1218 struct ext2_sb_info *sbi = EXT2_SB(sb);
1219 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1220
1221 /*
1222 * Write quota structures to quota file, sync_blockdev() will write
1223 * them to disk later
1224 */
1225 dquot_writeback_dquots(sb, -1);
1226
1227 spin_lock(&sbi->s_lock);
1228 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1229 ext2_debug("setting valid to 0\n");
1230 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1231 }
1232 spin_unlock(&sbi->s_lock);
1233 ext2_sync_super(sb, es, wait);
1234 return 0;
1235 }
1236
1237 static int ext2_freeze(struct super_block *sb)
1238 {
1239 struct ext2_sb_info *sbi = EXT2_SB(sb);
1240
1241 /*
1242 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1243 * because we have unattached inodes and thus filesystem is not fully
1244 * consistent.
1245 */
1246 if (atomic_long_read(&sb->s_remove_count)) {
1247 ext2_sync_fs(sb, 1);
1248 return 0;
1249 }
1250 /* Set EXT2_FS_VALID flag */
1251 spin_lock(&sbi->s_lock);
1252 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1253 spin_unlock(&sbi->s_lock);
1254 ext2_sync_super(sb, sbi->s_es, 1);
1255
1256 return 0;
1257 }
1258
1259 static int ext2_unfreeze(struct super_block *sb)
1260 {
1261 /* Just write sb to clear EXT2_VALID_FS flag */
1262 ext2_write_super(sb);
1263
1264 return 0;
1265 }
1266
1267 void ext2_write_super(struct super_block *sb)
1268 {
1269 if (!(sb->s_flags & MS_RDONLY))
1270 ext2_sync_fs(sb, 1);
1271 }
1272
1273 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1274 {
1275 struct ext2_sb_info * sbi = EXT2_SB(sb);
1276 struct ext2_super_block * es;
1277 struct ext2_mount_options old_opts;
1278 unsigned long old_sb_flags;
1279 int err;
1280
1281 sync_filesystem(sb);
1282 spin_lock(&sbi->s_lock);
1283
1284 /* Store the old options */
1285 old_sb_flags = sb->s_flags;
1286 old_opts.s_mount_opt = sbi->s_mount_opt;
1287 old_opts.s_resuid = sbi->s_resuid;
1288 old_opts.s_resgid = sbi->s_resgid;
1289
1290 /*
1291 * Allow the "check" option to be passed as a remount option.
1292 */
1293 if (!parse_options(data, sb)) {
1294 err = -EINVAL;
1295 goto restore_opts;
1296 }
1297
1298 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1299 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1300
1301 es = sbi->s_es;
1302 if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1303 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1304 "dax flag with busy inodes while remounting");
1305 sbi->s_mount_opt ^= EXT2_MOUNT_DAX;
1306 }
1307 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
1308 spin_unlock(&sbi->s_lock);
1309 return 0;
1310 }
1311 if (*flags & MS_RDONLY) {
1312 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1313 !(sbi->s_mount_state & EXT2_VALID_FS)) {
1314 spin_unlock(&sbi->s_lock);
1315 return 0;
1316 }
1317
1318 /*
1319 * OK, we are remounting a valid rw partition rdonly, so set
1320 * the rdonly flag and then mark the partition as valid again.
1321 */
1322 es->s_state = cpu_to_le16(sbi->s_mount_state);
1323 es->s_mtime = cpu_to_le32(get_seconds());
1324 spin_unlock(&sbi->s_lock);
1325
1326 err = dquot_suspend(sb, -1);
1327 if (err < 0) {
1328 spin_lock(&sbi->s_lock);
1329 goto restore_opts;
1330 }
1331
1332 ext2_sync_super(sb, es, 1);
1333 } else {
1334 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1335 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1336 if (ret) {
1337 ext2_msg(sb, KERN_WARNING,
1338 "warning: couldn't remount RDWR because of "
1339 "unsupported optional features (%x).",
1340 le32_to_cpu(ret));
1341 err = -EROFS;
1342 goto restore_opts;
1343 }
1344 /*
1345 * Mounting a RDONLY partition read-write, so reread and
1346 * store the current valid flag. (It may have been changed
1347 * by e2fsck since we originally mounted the partition.)
1348 */
1349 sbi->s_mount_state = le16_to_cpu(es->s_state);
1350 if (!ext2_setup_super (sb, es, 0))
1351 sb->s_flags &= ~MS_RDONLY;
1352 spin_unlock(&sbi->s_lock);
1353
1354 ext2_write_super(sb);
1355
1356 dquot_resume(sb, -1);
1357 }
1358
1359 return 0;
1360 restore_opts:
1361 sbi->s_mount_opt = old_opts.s_mount_opt;
1362 sbi->s_resuid = old_opts.s_resuid;
1363 sbi->s_resgid = old_opts.s_resgid;
1364 sb->s_flags = old_sb_flags;
1365 spin_unlock(&sbi->s_lock);
1366 return err;
1367 }
1368
1369 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1370 {
1371 struct super_block *sb = dentry->d_sb;
1372 struct ext2_sb_info *sbi = EXT2_SB(sb);
1373 struct ext2_super_block *es = sbi->s_es;
1374 u64 fsid;
1375
1376 spin_lock(&sbi->s_lock);
1377
1378 if (test_opt (sb, MINIX_DF))
1379 sbi->s_overhead_last = 0;
1380 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1381 unsigned long i, overhead = 0;
1382 smp_rmb();
1383
1384 /*
1385 * Compute the overhead (FS structures). This is constant
1386 * for a given filesystem unless the number of block groups
1387 * changes so we cache the previous value until it does.
1388 */
1389
1390 /*
1391 * All of the blocks before first_data_block are
1392 * overhead
1393 */
1394 overhead = le32_to_cpu(es->s_first_data_block);
1395
1396 /*
1397 * Add the overhead attributed to the superblock and
1398 * block group descriptors. If the sparse superblocks
1399 * feature is turned on, then not all groups have this.
1400 */
1401 for (i = 0; i < sbi->s_groups_count; i++)
1402 overhead += ext2_bg_has_super(sb, i) +
1403 ext2_bg_num_gdb(sb, i);
1404
1405 /*
1406 * Every block group has an inode bitmap, a block
1407 * bitmap, and an inode table.
1408 */
1409 overhead += (sbi->s_groups_count *
1410 (2 + sbi->s_itb_per_group));
1411 sbi->s_overhead_last = overhead;
1412 smp_wmb();
1413 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1414 }
1415
1416 buf->f_type = EXT2_SUPER_MAGIC;
1417 buf->f_bsize = sb->s_blocksize;
1418 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1419 buf->f_bfree = ext2_count_free_blocks(sb);
1420 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1421 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1422 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1423 buf->f_bavail = 0;
1424 buf->f_files = le32_to_cpu(es->s_inodes_count);
1425 buf->f_ffree = ext2_count_free_inodes(sb);
1426 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1427 buf->f_namelen = EXT2_NAME_LEN;
1428 fsid = le64_to_cpup((void *)es->s_uuid) ^
1429 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1430 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1431 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1432 spin_unlock(&sbi->s_lock);
1433 return 0;
1434 }
1435
1436 static struct dentry *ext2_mount(struct file_system_type *fs_type,
1437 int flags, const char *dev_name, void *data)
1438 {
1439 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1440 }
1441
1442 #ifdef CONFIG_QUOTA
1443
1444 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1445 * acquiring the locks... As quota files are never truncated and quota code
1446 * itself serializes the operations (and no one else should touch the files)
1447 * we don't have to be afraid of races */
1448 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1449 size_t len, loff_t off)
1450 {
1451 struct inode *inode = sb_dqopt(sb)->files[type];
1452 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1453 int err = 0;
1454 int offset = off & (sb->s_blocksize - 1);
1455 int tocopy;
1456 size_t toread;
1457 struct buffer_head tmp_bh;
1458 struct buffer_head *bh;
1459 loff_t i_size = i_size_read(inode);
1460
1461 if (off > i_size)
1462 return 0;
1463 if (off+len > i_size)
1464 len = i_size-off;
1465 toread = len;
1466 while (toread > 0) {
1467 tocopy = sb->s_blocksize - offset < toread ?
1468 sb->s_blocksize - offset : toread;
1469
1470 tmp_bh.b_state = 0;
1471 tmp_bh.b_size = sb->s_blocksize;
1472 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1473 if (err < 0)
1474 return err;
1475 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1476 memset(data, 0, tocopy);
1477 else {
1478 bh = sb_bread(sb, tmp_bh.b_blocknr);
1479 if (!bh)
1480 return -EIO;
1481 memcpy(data, bh->b_data+offset, tocopy);
1482 brelse(bh);
1483 }
1484 offset = 0;
1485 toread -= tocopy;
1486 data += tocopy;
1487 blk++;
1488 }
1489 return len;
1490 }
1491
1492 /* Write to quotafile */
1493 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1494 const char *data, size_t len, loff_t off)
1495 {
1496 struct inode *inode = sb_dqopt(sb)->files[type];
1497 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1498 int err = 0;
1499 int offset = off & (sb->s_blocksize - 1);
1500 int tocopy;
1501 size_t towrite = len;
1502 struct buffer_head tmp_bh;
1503 struct buffer_head *bh;
1504
1505 while (towrite > 0) {
1506 tocopy = sb->s_blocksize - offset < towrite ?
1507 sb->s_blocksize - offset : towrite;
1508
1509 tmp_bh.b_state = 0;
1510 tmp_bh.b_size = sb->s_blocksize;
1511 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1512 if (err < 0)
1513 goto out;
1514 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1515 bh = sb_bread(sb, tmp_bh.b_blocknr);
1516 else
1517 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1518 if (unlikely(!bh)) {
1519 err = -EIO;
1520 goto out;
1521 }
1522 lock_buffer(bh);
1523 memcpy(bh->b_data+offset, data, tocopy);
1524 flush_dcache_page(bh->b_page);
1525 set_buffer_uptodate(bh);
1526 mark_buffer_dirty(bh);
1527 unlock_buffer(bh);
1528 brelse(bh);
1529 offset = 0;
1530 towrite -= tocopy;
1531 data += tocopy;
1532 blk++;
1533 }
1534 out:
1535 if (len == towrite)
1536 return err;
1537 if (inode->i_size < off+len-towrite)
1538 i_size_write(inode, off+len-towrite);
1539 inode->i_version++;
1540 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1541 mark_inode_dirty(inode);
1542 return len - towrite;
1543 }
1544
1545 #endif
1546
1547 static struct file_system_type ext2_fs_type = {
1548 .owner = THIS_MODULE,
1549 .name = "ext2",
1550 .mount = ext2_mount,
1551 .kill_sb = kill_block_super,
1552 .fs_flags = FS_REQUIRES_DEV,
1553 };
1554 MODULE_ALIAS_FS("ext2");
1555
1556 static int __init init_ext2_fs(void)
1557 {
1558 int err = init_ext2_xattr();
1559 if (err)
1560 return err;
1561 err = init_inodecache();
1562 if (err)
1563 goto out1;
1564 err = register_filesystem(&ext2_fs_type);
1565 if (err)
1566 goto out;
1567 return 0;
1568 out:
1569 destroy_inodecache();
1570 out1:
1571 exit_ext2_xattr();
1572 return err;
1573 }
1574
1575 static void __exit exit_ext2_fs(void)
1576 {
1577 unregister_filesystem(&ext2_fs_type);
1578 destroy_inodecache();
1579 exit_ext2_xattr();
1580 }
1581
1582 MODULE_AUTHOR("Remy Card and others");
1583 MODULE_DESCRIPTION("Second Extended Filesystem");
1584 MODULE_LICENSE("GPL");
1585 module_init(init_ext2_fs)
1586 module_exit(exit_ext2_fs)
Ubuntu Artful kernel mirror