Loading...
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
42static void ext2_write_super(struct super_block *sb);
43static int ext2_remount (struct super_block * sb, int * flags, char * data);
44static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
45static int ext2_sync_fs(struct super_block *sb, int wait);
46static int ext2_freeze(struct super_block *sb);
47static int ext2_unfreeze(struct super_block *sb);
48
49void 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
84void 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 */
103void 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
129static int ext2_quota_off(struct super_block *sb, int type);
130
131static 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
139static inline void ext2_quota_off_umount(struct super_block *sb)
140{
141}
142#endif
143
144static 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 kvfree(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, NULL);
175 kfree(sbi);
176}
177
178static struct kmem_cache * ext2_inode_cachep;
179
180static struct inode *ext2_alloc_inode(struct super_block *sb)
181{
182 struct ext2_inode_info *ei;
183 ei = alloc_inode_sb(sb, 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
195static void ext2_free_in_core_inode(struct inode *inode)
196{
197 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
198}
199
200static 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 inode_init_once(&ei->vfs_inode);
210}
211
212static int __init init_inodecache(void)
213{
214 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",
215 sizeof(struct ext2_inode_info), 0,
216 SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
217 offsetof(struct ext2_inode_info, i_data),
218 sizeof_field(struct ext2_inode_info, i_data),
219 init_once);
220 if (ext2_inode_cachep == NULL)
221 return -ENOMEM;
222 return 0;
223}
224
225static void destroy_inodecache(void)
226{
227 /*
228 * Make sure all delayed rcu free inodes are flushed before we
229 * destroy cache.
230 */
231 rcu_barrier();
232 kmem_cache_destroy(ext2_inode_cachep);
233}
234
235static int ext2_show_options(struct seq_file *seq, struct dentry *root)
236{
237 struct super_block *sb = root->d_sb;
238 struct ext2_sb_info *sbi = EXT2_SB(sb);
239 struct ext2_super_block *es = sbi->s_es;
240 unsigned long def_mount_opts;
241
242 spin_lock(&sbi->s_lock);
243 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
244
245 if (sbi->s_sb_block != 1)
246 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
247 if (test_opt(sb, MINIX_DF))
248 seq_puts(seq, ",minixdf");
249 if (test_opt(sb, GRPID))
250 seq_puts(seq, ",grpid");
251 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
252 seq_puts(seq, ",nogrpid");
253 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
254 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
255 seq_printf(seq, ",resuid=%u",
256 from_kuid_munged(&init_user_ns, sbi->s_resuid));
257 }
258 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
259 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
260 seq_printf(seq, ",resgid=%u",
261 from_kgid_munged(&init_user_ns, sbi->s_resgid));
262 }
263 if (test_opt(sb, ERRORS_RO)) {
264 int def_errors = le16_to_cpu(es->s_errors);
265
266 if (def_errors == EXT2_ERRORS_PANIC ||
267 def_errors == EXT2_ERRORS_CONTINUE) {
268 seq_puts(seq, ",errors=remount-ro");
269 }
270 }
271 if (test_opt(sb, ERRORS_CONT))
272 seq_puts(seq, ",errors=continue");
273 if (test_opt(sb, ERRORS_PANIC))
274 seq_puts(seq, ",errors=panic");
275 if (test_opt(sb, NO_UID32))
276 seq_puts(seq, ",nouid32");
277 if (test_opt(sb, DEBUG))
278 seq_puts(seq, ",debug");
279 if (test_opt(sb, OLDALLOC))
280 seq_puts(seq, ",oldalloc");
281
282#ifdef CONFIG_EXT2_FS_XATTR
283 if (test_opt(sb, XATTR_USER))
284 seq_puts(seq, ",user_xattr");
285 if (!test_opt(sb, XATTR_USER) &&
286 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
287 seq_puts(seq, ",nouser_xattr");
288 }
289#endif
290
291#ifdef CONFIG_EXT2_FS_POSIX_ACL
292 if (test_opt(sb, POSIX_ACL))
293 seq_puts(seq, ",acl");
294 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
295 seq_puts(seq, ",noacl");
296#endif
297
298 if (test_opt(sb, USRQUOTA))
299 seq_puts(seq, ",usrquota");
300
301 if (test_opt(sb, GRPQUOTA))
302 seq_puts(seq, ",grpquota");
303
304 if (test_opt(sb, XIP))
305 seq_puts(seq, ",xip");
306
307 if (test_opt(sb, DAX))
308 seq_puts(seq, ",dax");
309
310 if (!test_opt(sb, RESERVATION))
311 seq_puts(seq, ",noreservation");
312
313 spin_unlock(&sbi->s_lock);
314 return 0;
315}
316
317#ifdef CONFIG_QUOTA
318static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
319static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
320static int ext2_quota_on(struct super_block *sb, int type, int format_id,
321 const struct path *path);
322static struct dquot __rcu **ext2_get_dquots(struct inode *inode)
323{
324 return EXT2_I(inode)->i_dquot;
325}
326
327static const struct quotactl_ops ext2_quotactl_ops = {
328 .quota_on = ext2_quota_on,
329 .quota_off = ext2_quota_off,
330 .quota_sync = dquot_quota_sync,
331 .get_state = dquot_get_state,
332 .set_info = dquot_set_dqinfo,
333 .get_dqblk = dquot_get_dqblk,
334 .set_dqblk = dquot_set_dqblk,
335 .get_nextdqblk = dquot_get_next_dqblk,
336};
337#endif
338
339static const struct super_operations ext2_sops = {
340 .alloc_inode = ext2_alloc_inode,
341 .free_inode = ext2_free_in_core_inode,
342 .write_inode = ext2_write_inode,
343 .evict_inode = ext2_evict_inode,
344 .put_super = ext2_put_super,
345 .sync_fs = ext2_sync_fs,
346 .freeze_fs = ext2_freeze,
347 .unfreeze_fs = ext2_unfreeze,
348 .statfs = ext2_statfs,
349 .remount_fs = ext2_remount,
350 .show_options = ext2_show_options,
351#ifdef CONFIG_QUOTA
352 .quota_read = ext2_quota_read,
353 .quota_write = ext2_quota_write,
354 .get_dquots = ext2_get_dquots,
355#endif
356};
357
358static struct inode *ext2_nfs_get_inode(struct super_block *sb,
359 u64 ino, u32 generation)
360{
361 struct inode *inode;
362
363 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
364 return ERR_PTR(-ESTALE);
365 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
366 return ERR_PTR(-ESTALE);
367
368 /*
369 * ext2_iget isn't quite right if the inode is currently unallocated!
370 * However ext2_iget currently does appropriate checks to handle stale
371 * inodes so everything is OK.
372 */
373 inode = ext2_iget(sb, ino);
374 if (IS_ERR(inode))
375 return ERR_CAST(inode);
376 if (generation && inode->i_generation != generation) {
377 /* we didn't find the right inode.. */
378 iput(inode);
379 return ERR_PTR(-ESTALE);
380 }
381 return inode;
382}
383
384static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
385 int fh_len, int fh_type)
386{
387 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
388 ext2_nfs_get_inode);
389}
390
391static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
392 int fh_len, int fh_type)
393{
394 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
395 ext2_nfs_get_inode);
396}
397
398static const struct export_operations ext2_export_ops = {
399 .encode_fh = generic_encode_ino32_fh,
400 .fh_to_dentry = ext2_fh_to_dentry,
401 .fh_to_parent = ext2_fh_to_parent,
402 .get_parent = ext2_get_parent,
403};
404
405static unsigned long get_sb_block(void **data)
406{
407 unsigned long sb_block;
408 char *options = (char *) *data;
409
410 if (!options || strncmp(options, "sb=", 3) != 0)
411 return 1; /* Default location */
412 options += 3;
413 sb_block = simple_strtoul(options, &options, 0);
414 if (*options && *options != ',') {
415 printk("EXT2-fs: Invalid sb specification: %s\n",
416 (char *) *data);
417 return 1;
418 }
419 if (*options == ',')
420 options++;
421 *data = (void *) options;
422 return sb_block;
423}
424
425enum {
426 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
427 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
428 Opt_err_ro, Opt_nouid32, Opt_debug,
429 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
430 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
431 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
432};
433
434static const match_table_t tokens = {
435 {Opt_bsd_df, "bsddf"},
436 {Opt_minix_df, "minixdf"},
437 {Opt_grpid, "grpid"},
438 {Opt_grpid, "bsdgroups"},
439 {Opt_nogrpid, "nogrpid"},
440 {Opt_nogrpid, "sysvgroups"},
441 {Opt_resgid, "resgid=%u"},
442 {Opt_resuid, "resuid=%u"},
443 {Opt_sb, "sb=%u"},
444 {Opt_err_cont, "errors=continue"},
445 {Opt_err_panic, "errors=panic"},
446 {Opt_err_ro, "errors=remount-ro"},
447 {Opt_nouid32, "nouid32"},
448 {Opt_debug, "debug"},
449 {Opt_oldalloc, "oldalloc"},
450 {Opt_orlov, "orlov"},
451 {Opt_nobh, "nobh"},
452 {Opt_user_xattr, "user_xattr"},
453 {Opt_nouser_xattr, "nouser_xattr"},
454 {Opt_acl, "acl"},
455 {Opt_noacl, "noacl"},
456 {Opt_xip, "xip"},
457 {Opt_dax, "dax"},
458 {Opt_grpquota, "grpquota"},
459 {Opt_ignore, "noquota"},
460 {Opt_quota, "quota"},
461 {Opt_usrquota, "usrquota"},
462 {Opt_reservation, "reservation"},
463 {Opt_noreservation, "noreservation"},
464 {Opt_err, NULL}
465};
466
467static int parse_options(char *options, struct super_block *sb,
468 struct ext2_mount_options *opts)
469{
470 char *p;
471 substring_t args[MAX_OPT_ARGS];
472 int option;
473 kuid_t uid;
474 kgid_t gid;
475
476 if (!options)
477 return 1;
478
479 while ((p = strsep (&options, ",")) != NULL) {
480 int token;
481 if (!*p)
482 continue;
483
484 token = match_token(p, tokens, args);
485 switch (token) {
486 case Opt_bsd_df:
487 clear_opt (opts->s_mount_opt, MINIX_DF);
488 break;
489 case Opt_minix_df:
490 set_opt (opts->s_mount_opt, MINIX_DF);
491 break;
492 case Opt_grpid:
493 set_opt (opts->s_mount_opt, GRPID);
494 break;
495 case Opt_nogrpid:
496 clear_opt (opts->s_mount_opt, GRPID);
497 break;
498 case Opt_resuid:
499 if (match_int(&args[0], &option))
500 return 0;
501 uid = make_kuid(current_user_ns(), option);
502 if (!uid_valid(uid)) {
503 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
504 return 0;
505
506 }
507 opts->s_resuid = uid;
508 break;
509 case Opt_resgid:
510 if (match_int(&args[0], &option))
511 return 0;
512 gid = make_kgid(current_user_ns(), option);
513 if (!gid_valid(gid)) {
514 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
515 return 0;
516 }
517 opts->s_resgid = gid;
518 break;
519 case Opt_sb:
520 /* handled by get_sb_block() instead of here */
521 /* *sb_block = match_int(&args[0]); */
522 break;
523 case Opt_err_panic:
524 clear_opt (opts->s_mount_opt, ERRORS_CONT);
525 clear_opt (opts->s_mount_opt, ERRORS_RO);
526 set_opt (opts->s_mount_opt, ERRORS_PANIC);
527 break;
528 case Opt_err_ro:
529 clear_opt (opts->s_mount_opt, ERRORS_CONT);
530 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
531 set_opt (opts->s_mount_opt, ERRORS_RO);
532 break;
533 case Opt_err_cont:
534 clear_opt (opts->s_mount_opt, ERRORS_RO);
535 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
536 set_opt (opts->s_mount_opt, ERRORS_CONT);
537 break;
538 case Opt_nouid32:
539 set_opt (opts->s_mount_opt, NO_UID32);
540 break;
541 case Opt_debug:
542 set_opt (opts->s_mount_opt, DEBUG);
543 break;
544 case Opt_oldalloc:
545 set_opt (opts->s_mount_opt, OLDALLOC);
546 break;
547 case Opt_orlov:
548 clear_opt (opts->s_mount_opt, OLDALLOC);
549 break;
550 case Opt_nobh:
551 ext2_msg(sb, KERN_INFO,
552 "nobh option not supported");
553 break;
554#ifdef CONFIG_EXT2_FS_XATTR
555 case Opt_user_xattr:
556 set_opt (opts->s_mount_opt, XATTR_USER);
557 break;
558 case Opt_nouser_xattr:
559 clear_opt (opts->s_mount_opt, XATTR_USER);
560 break;
561#else
562 case Opt_user_xattr:
563 case Opt_nouser_xattr:
564 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
565 "not supported");
566 break;
567#endif
568#ifdef CONFIG_EXT2_FS_POSIX_ACL
569 case Opt_acl:
570 set_opt(opts->s_mount_opt, POSIX_ACL);
571 break;
572 case Opt_noacl:
573 clear_opt(opts->s_mount_opt, POSIX_ACL);
574 break;
575#else
576 case Opt_acl:
577 case Opt_noacl:
578 ext2_msg(sb, KERN_INFO,
579 "(no)acl options not supported");
580 break;
581#endif
582 case Opt_xip:
583 ext2_msg(sb, KERN_INFO, "use dax instead of xip");
584 set_opt(opts->s_mount_opt, XIP);
585 fallthrough;
586 case Opt_dax:
587#ifdef CONFIG_FS_DAX
588 ext2_msg(sb, KERN_WARNING,
589 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
590 set_opt(opts->s_mount_opt, DAX);
591#else
592 ext2_msg(sb, KERN_INFO, "dax option not supported");
593#endif
594 break;
595
596#if defined(CONFIG_QUOTA)
597 case Opt_quota:
598 case Opt_usrquota:
599 set_opt(opts->s_mount_opt, USRQUOTA);
600 break;
601
602 case Opt_grpquota:
603 set_opt(opts->s_mount_opt, GRPQUOTA);
604 break;
605#else
606 case Opt_quota:
607 case Opt_usrquota:
608 case Opt_grpquota:
609 ext2_msg(sb, KERN_INFO,
610 "quota operations not supported");
611 break;
612#endif
613
614 case Opt_reservation:
615 set_opt(opts->s_mount_opt, RESERVATION);
616 ext2_msg(sb, KERN_INFO, "reservations ON");
617 break;
618 case Opt_noreservation:
619 clear_opt(opts->s_mount_opt, RESERVATION);
620 ext2_msg(sb, KERN_INFO, "reservations OFF");
621 break;
622 case Opt_ignore:
623 break;
624 default:
625 return 0;
626 }
627 }
628 return 1;
629}
630
631static int ext2_setup_super (struct super_block * sb,
632 struct ext2_super_block * es,
633 int read_only)
634{
635 int res = 0;
636 struct ext2_sb_info *sbi = EXT2_SB(sb);
637
638 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
639 ext2_msg(sb, KERN_ERR,
640 "error: revision level too high, "
641 "forcing read-only mode");
642 res = SB_RDONLY;
643 }
644 if (read_only)
645 return res;
646 if (!(sbi->s_mount_state & EXT2_VALID_FS))
647 ext2_msg(sb, KERN_WARNING,
648 "warning: mounting unchecked fs, "
649 "running e2fsck is recommended");
650 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
651 ext2_msg(sb, KERN_WARNING,
652 "warning: mounting fs with errors, "
653 "running e2fsck is recommended");
654 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
655 le16_to_cpu(es->s_mnt_count) >=
656 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
657 ext2_msg(sb, KERN_WARNING,
658 "warning: maximal mount count reached, "
659 "running e2fsck is recommended");
660 else if (le32_to_cpu(es->s_checkinterval) &&
661 (le32_to_cpu(es->s_lastcheck) +
662 le32_to_cpu(es->s_checkinterval) <=
663 ktime_get_real_seconds()))
664 ext2_msg(sb, KERN_WARNING,
665 "warning: checktime reached, "
666 "running e2fsck is recommended");
667 if (!le16_to_cpu(es->s_max_mnt_count))
668 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
669 le16_add_cpu(&es->s_mnt_count, 1);
670 if (test_opt (sb, DEBUG))
671 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, "
672 "bpg=%lu, ipg=%lu, mo=%04lx]",
673 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
674 sbi->s_groups_count,
675 EXT2_BLOCKS_PER_GROUP(sb),
676 EXT2_INODES_PER_GROUP(sb),
677 sbi->s_mount_opt);
678 return res;
679}
680
681static int ext2_check_descriptors(struct super_block *sb)
682{
683 int i;
684 struct ext2_sb_info *sbi = EXT2_SB(sb);
685
686 ext2_debug ("Checking group descriptors");
687
688 for (i = 0; i < sbi->s_groups_count; i++) {
689 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
690 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
691 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i);
692
693 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
694 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
695 {
696 ext2_error (sb, "ext2_check_descriptors",
697 "Block bitmap for group %d"
698 " not in group (block %lu)!",
699 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
700 return 0;
701 }
702 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
703 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
704 {
705 ext2_error (sb, "ext2_check_descriptors",
706 "Inode bitmap for group %d"
707 " not in group (block %lu)!",
708 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
709 return 0;
710 }
711 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
712 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
713 last_block)
714 {
715 ext2_error (sb, "ext2_check_descriptors",
716 "Inode table for group %d"
717 " not in group (block %lu)!",
718 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
719 return 0;
720 }
721 }
722 return 1;
723}
724
725/*
726 * Maximal file size. There is a direct, and {,double-,triple-}indirect
727 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
728 * We need to be 1 filesystem block less than the 2^32 sector limit.
729 */
730static loff_t ext2_max_size(int bits)
731{
732 loff_t res = EXT2_NDIR_BLOCKS;
733 int meta_blocks;
734 unsigned int upper_limit;
735 unsigned int ppb = 1 << (bits-2);
736
737 /* This is calculated to be the largest file size for a
738 * dense, file such that the total number of
739 * sectors in the file, including data and all indirect blocks,
740 * does not exceed 2^32 -1
741 * __u32 i_blocks representing the total number of
742 * 512 bytes blocks of the file
743 */
744 upper_limit = (1LL << 32) - 1;
745
746 /* total blocks in file system block size */
747 upper_limit >>= (bits - 9);
748
749 /* Compute how many blocks we can address by block tree */
750 res += 1LL << (bits-2);
751 res += 1LL << (2*(bits-2));
752 res += 1LL << (3*(bits-2));
753 /* Compute how many metadata blocks are needed */
754 meta_blocks = 1;
755 meta_blocks += 1 + ppb;
756 meta_blocks += 1 + ppb + ppb * ppb;
757 /* Does block tree limit file size? */
758 if (res + meta_blocks <= upper_limit)
759 goto check_lfs;
760
761 res = upper_limit;
762 /* How many metadata blocks are needed for addressing upper_limit? */
763 upper_limit -= EXT2_NDIR_BLOCKS;
764 /* indirect blocks */
765 meta_blocks = 1;
766 upper_limit -= ppb;
767 /* double indirect blocks */
768 if (upper_limit < ppb * ppb) {
769 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
770 res -= meta_blocks;
771 goto check_lfs;
772 }
773 meta_blocks += 1 + ppb;
774 upper_limit -= ppb * ppb;
775 /* tripple indirect blocks for the rest */
776 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
777 DIV_ROUND_UP(upper_limit, ppb*ppb);
778 res -= meta_blocks;
779check_lfs:
780 res <<= bits;
781 if (res > MAX_LFS_FILESIZE)
782 res = MAX_LFS_FILESIZE;
783
784 return res;
785}
786
787static unsigned long descriptor_loc(struct super_block *sb,
788 unsigned long logic_sb_block,
789 int nr)
790{
791 struct ext2_sb_info *sbi = EXT2_SB(sb);
792 unsigned long bg, first_meta_bg;
793
794 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
795
796 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
797 nr < first_meta_bg)
798 return (logic_sb_block + nr + 1);
799 bg = sbi->s_desc_per_block * nr;
800
801 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);
802}
803
804static int ext2_fill_super(struct super_block *sb, void *data, int silent)
805{
806 struct buffer_head * bh;
807 struct ext2_sb_info * sbi;
808 struct ext2_super_block * es;
809 struct inode *root;
810 unsigned long block;
811 unsigned long sb_block = get_sb_block(&data);
812 unsigned long logic_sb_block;
813 unsigned long offset = 0;
814 unsigned long def_mount_opts;
815 long ret = -ENOMEM;
816 int blocksize = BLOCK_SIZE;
817 int db_count;
818 int i, j;
819 __le32 features;
820 int err;
821 struct ext2_mount_options opts;
822
823 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
824 if (!sbi)
825 return -ENOMEM;
826
827 sbi->s_blockgroup_lock =
828 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
829 if (!sbi->s_blockgroup_lock) {
830 kfree(sbi);
831 return -ENOMEM;
832 }
833 sb->s_fs_info = sbi;
834 sbi->s_sb_block = sb_block;
835 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
836 NULL, NULL);
837
838 spin_lock_init(&sbi->s_lock);
839 ret = -EINVAL;
840
841 /*
842 * See what the current blocksize for the device is, and
843 * use that as the blocksize. Otherwise (or if the blocksize
844 * is smaller than the default) use the default.
845 * This is important for devices that have a hardware
846 * sectorsize that is larger than the default.
847 */
848 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
849 if (!blocksize) {
850 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
851 goto failed_sbi;
852 }
853
854 /*
855 * If the superblock doesn't start on a hardware sector boundary,
856 * calculate the offset.
857 */
858 if (blocksize != BLOCK_SIZE) {
859 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
860 offset = (sb_block*BLOCK_SIZE) % blocksize;
861 } else {
862 logic_sb_block = sb_block;
863 }
864
865 if (!(bh = sb_bread(sb, logic_sb_block))) {
866 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
867 goto failed_sbi;
868 }
869 /*
870 * Note: s_es must be initialized as soon as possible because
871 * some ext2 macro-instructions depend on its value
872 */
873 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
874 sbi->s_es = es;
875 sb->s_magic = le16_to_cpu(es->s_magic);
876
877 if (sb->s_magic != EXT2_SUPER_MAGIC)
878 goto cantfind_ext2;
879
880 opts.s_mount_opt = 0;
881 /* Set defaults before we parse the mount options */
882 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
883 if (def_mount_opts & EXT2_DEFM_DEBUG)
884 set_opt(opts.s_mount_opt, DEBUG);
885 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
886 set_opt(opts.s_mount_opt, GRPID);
887 if (def_mount_opts & EXT2_DEFM_UID16)
888 set_opt(opts.s_mount_opt, NO_UID32);
889#ifdef CONFIG_EXT2_FS_XATTR
890 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
891 set_opt(opts.s_mount_opt, XATTR_USER);
892#endif
893#ifdef CONFIG_EXT2_FS_POSIX_ACL
894 if (def_mount_opts & EXT2_DEFM_ACL)
895 set_opt(opts.s_mount_opt, POSIX_ACL);
896#endif
897
898 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
899 set_opt(opts.s_mount_opt, ERRORS_PANIC);
900 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
901 set_opt(opts.s_mount_opt, ERRORS_CONT);
902 else
903 set_opt(opts.s_mount_opt, ERRORS_RO);
904
905 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
906 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
907
908 set_opt(opts.s_mount_opt, RESERVATION);
909
910 if (!parse_options((char *) data, sb, &opts))
911 goto failed_mount;
912
913 sbi->s_mount_opt = opts.s_mount_opt;
914 sbi->s_resuid = opts.s_resuid;
915 sbi->s_resgid = opts.s_resgid;
916
917 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
918 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
919 sb->s_iflags |= SB_I_CGROUPWB;
920
921 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
922 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
923 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
924 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
925 ext2_msg(sb, KERN_WARNING,
926 "warning: feature flags set on rev 0 fs, "
927 "running e2fsck is recommended");
928 /*
929 * Check feature flags regardless of the revision level, since we
930 * previously didn't change the revision level when setting the flags,
931 * so there is a chance incompat flags are set on a rev 0 filesystem.
932 */
933 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
934 if (features) {
935 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
936 "unsupported optional features (%x)",
937 le32_to_cpu(features));
938 goto failed_mount;
939 }
940 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
941 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
942 "unsupported optional features (%x)",
943 le32_to_cpu(features));
944 goto failed_mount;
945 }
946
947 if (le32_to_cpu(es->s_log_block_size) >
948 (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) {
949 ext2_msg(sb, KERN_ERR,
950 "Invalid log block size: %u",
951 le32_to_cpu(es->s_log_block_size));
952 goto failed_mount;
953 }
954 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
955
956 if (test_opt(sb, DAX)) {
957 if (!sbi->s_daxdev) {
958 ext2_msg(sb, KERN_ERR,
959 "DAX unsupported by block device. Turning off DAX.");
960 clear_opt(sbi->s_mount_opt, DAX);
961 } else if (blocksize != PAGE_SIZE) {
962 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
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_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1015 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1016
1017 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1018 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1019 goto cantfind_ext2;
1020 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1021 sbi->s_inodes_per_block;
1022 sbi->s_desc_per_block = sb->s_blocksize /
1023 sizeof (struct ext2_group_desc);
1024 sbi->s_sbh = bh;
1025 sbi->s_mount_state = le16_to_cpu(es->s_state);
1026 sbi->s_addr_per_block_bits =
1027 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1028 sbi->s_desc_per_block_bits =
1029 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1030
1031 if (sb->s_magic != EXT2_SUPER_MAGIC)
1032 goto cantfind_ext2;
1033
1034 if (sb->s_blocksize != bh->b_size) {
1035 if (!silent)
1036 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1037 goto failed_mount;
1038 }
1039
1040 if (es->s_log_frag_size != es->s_log_block_size) {
1041 ext2_msg(sb, KERN_ERR,
1042 "error: fragsize log %u != blocksize log %u",
1043 le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits);
1044 goto failed_mount;
1045 }
1046
1047 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1048 ext2_msg(sb, KERN_ERR,
1049 "error: #blocks per group too big: %lu",
1050 sbi->s_blocks_per_group);
1051 goto failed_mount;
1052 }
1053 /* At least inode table, bitmaps, and sb have to fit in one group */
1054 if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) {
1055 ext2_msg(sb, KERN_ERR,
1056 "error: #blocks per group smaller than metadata size: %lu <= %lu",
1057 sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3);
1058 goto failed_mount;
1059 }
1060 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
1061 sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1062 ext2_msg(sb, KERN_ERR,
1063 "error: invalid #inodes per group: %lu",
1064 sbi->s_inodes_per_group);
1065 goto failed_mount;
1066 }
1067 if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) {
1068 ext2_msg(sb, KERN_ERR,
1069 "bad geometry: block count %u exceeds size of device (%u blocks)",
1070 le32_to_cpu(es->s_blocks_count),
1071 (unsigned)sb_bdev_nr_blocks(sb));
1072 goto failed_mount;
1073 }
1074
1075 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1076 le32_to_cpu(es->s_first_data_block) - 1)
1077 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1078 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=
1079 le32_to_cpu(es->s_inodes_count)) {
1080 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",
1081 le32_to_cpu(es->s_inodes_count),
1082 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);
1083 goto failed_mount;
1084 }
1085 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1086 EXT2_DESC_PER_BLOCK(sb);
1087 sbi->s_group_desc = kvmalloc_array(db_count,
1088 sizeof(struct buffer_head *),
1089 GFP_KERNEL);
1090 if (sbi->s_group_desc == NULL) {
1091 ret = -ENOMEM;
1092 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1093 goto failed_mount;
1094 }
1095 bgl_lock_init(sbi->s_blockgroup_lock);
1096 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1097 if (!sbi->s_debts) {
1098 ret = -ENOMEM;
1099 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1100 goto failed_mount_group_desc;
1101 }
1102 for (i = 0; i < db_count; i++) {
1103 block = descriptor_loc(sb, logic_sb_block, i);
1104 sbi->s_group_desc[i] = sb_bread(sb, block);
1105 if (!sbi->s_group_desc[i]) {
1106 for (j = 0; j < i; j++)
1107 brelse (sbi->s_group_desc[j]);
1108 ext2_msg(sb, KERN_ERR,
1109 "error: unable to read group descriptors");
1110 goto failed_mount_group_desc;
1111 }
1112 }
1113 if (!ext2_check_descriptors (sb)) {
1114 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1115 goto failed_mount2;
1116 }
1117 sbi->s_gdb_count = db_count;
1118 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1119 spin_lock_init(&sbi->s_next_gen_lock);
1120
1121 /* per filesystem reservation list head & lock */
1122 spin_lock_init(&sbi->s_rsv_window_lock);
1123 sbi->s_rsv_window_root = RB_ROOT;
1124 /*
1125 * Add a single, static dummy reservation to the start of the
1126 * reservation window list --- it gives us a placeholder for
1127 * append-at-start-of-list which makes the allocation logic
1128 * _much_ simpler.
1129 */
1130 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1131 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1132 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1133 sbi->s_rsv_window_head.rsv_goal_size = 0;
1134 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1135
1136 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1137 ext2_count_free_blocks(sb), GFP_KERNEL);
1138 if (!err) {
1139 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1140 ext2_count_free_inodes(sb), GFP_KERNEL);
1141 }
1142 if (!err) {
1143 err = percpu_counter_init(&sbi->s_dirs_counter,
1144 ext2_count_dirs(sb), GFP_KERNEL);
1145 }
1146 if (err) {
1147 ret = err;
1148 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1149 goto failed_mount3;
1150 }
1151
1152#ifdef CONFIG_EXT2_FS_XATTR
1153 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1154 if (!sbi->s_ea_block_cache) {
1155 ret = -ENOMEM;
1156 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1157 goto failed_mount3;
1158 }
1159#endif
1160 /*
1161 * set up enough so that it can read an inode
1162 */
1163 sb->s_op = &ext2_sops;
1164 sb->s_export_op = &ext2_export_ops;
1165 sb->s_xattr = ext2_xattr_handlers;
1166
1167#ifdef CONFIG_QUOTA
1168 sb->dq_op = &dquot_operations;
1169 sb->s_qcop = &ext2_quotactl_ops;
1170 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1171#endif
1172
1173 root = ext2_iget(sb, EXT2_ROOT_INO);
1174 if (IS_ERR(root)) {
1175 ret = PTR_ERR(root);
1176 goto failed_mount3;
1177 }
1178 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1179 iput(root);
1180 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1181 goto failed_mount3;
1182 }
1183
1184 sb->s_root = d_make_root(root);
1185 if (!sb->s_root) {
1186 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1187 ret = -ENOMEM;
1188 goto failed_mount3;
1189 }
1190 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1191 ext2_msg(sb, KERN_WARNING,
1192 "warning: mounting ext3 filesystem as ext2");
1193 if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1194 sb->s_flags |= SB_RDONLY;
1195 ext2_write_super(sb);
1196 return 0;
1197
1198cantfind_ext2:
1199 if (!silent)
1200 ext2_msg(sb, KERN_ERR,
1201 "error: can't find an ext2 filesystem on dev %s.",
1202 sb->s_id);
1203 goto failed_mount;
1204failed_mount3:
1205 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1206 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1207 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1208 percpu_counter_destroy(&sbi->s_dirs_counter);
1209failed_mount2:
1210 for (i = 0; i < db_count; i++)
1211 brelse(sbi->s_group_desc[i]);
1212failed_mount_group_desc:
1213 kvfree(sbi->s_group_desc);
1214 kfree(sbi->s_debts);
1215failed_mount:
1216 brelse(bh);
1217failed_sbi:
1218 fs_put_dax(sbi->s_daxdev, NULL);
1219 sb->s_fs_info = NULL;
1220 kfree(sbi->s_blockgroup_lock);
1221 kfree(sbi);
1222 return ret;
1223}
1224
1225static void ext2_clear_super_error(struct super_block *sb)
1226{
1227 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1228
1229 if (buffer_write_io_error(sbh)) {
1230 /*
1231 * Oh, dear. A previous attempt to write the
1232 * superblock failed. This could happen because the
1233 * USB device was yanked out. Or it could happen to
1234 * be a transient write error and maybe the block will
1235 * be remapped. Nothing we can do but to retry the
1236 * write and hope for the best.
1237 */
1238 ext2_msg(sb, KERN_ERR,
1239 "previous I/O error to superblock detected");
1240 clear_buffer_write_io_error(sbh);
1241 set_buffer_uptodate(sbh);
1242 }
1243}
1244
1245void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1246 int wait)
1247{
1248 ext2_clear_super_error(sb);
1249 spin_lock(&EXT2_SB(sb)->s_lock);
1250 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1251 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1252 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1253 /* unlock before we do IO */
1254 spin_unlock(&EXT2_SB(sb)->s_lock);
1255 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1256 if (wait)
1257 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1258}
1259
1260/*
1261 * In the second extended file system, it is not necessary to
1262 * write the super block since we use a mapping of the
1263 * disk super block in a buffer.
1264 *
1265 * However, this function is still used to set the fs valid
1266 * flags to 0. We need to set this flag to 0 since the fs
1267 * may have been checked while mounted and e2fsck may have
1268 * set s_state to EXT2_VALID_FS after some corrections.
1269 */
1270static int ext2_sync_fs(struct super_block *sb, int wait)
1271{
1272 struct ext2_sb_info *sbi = EXT2_SB(sb);
1273 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1274
1275 /*
1276 * Write quota structures to quota file, sync_blockdev() will write
1277 * them to disk later
1278 */
1279 dquot_writeback_dquots(sb, -1);
1280
1281 spin_lock(&sbi->s_lock);
1282 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1283 ext2_debug("setting valid to 0\n");
1284 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1285 }
1286 spin_unlock(&sbi->s_lock);
1287 ext2_sync_super(sb, es, wait);
1288 return 0;
1289}
1290
1291static int ext2_freeze(struct super_block *sb)
1292{
1293 struct ext2_sb_info *sbi = EXT2_SB(sb);
1294
1295 /*
1296 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1297 * because we have unattached inodes and thus filesystem is not fully
1298 * consistent.
1299 */
1300 if (atomic_long_read(&sb->s_remove_count)) {
1301 ext2_sync_fs(sb, 1);
1302 return 0;
1303 }
1304 /* Set EXT2_FS_VALID flag */
1305 spin_lock(&sbi->s_lock);
1306 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1307 spin_unlock(&sbi->s_lock);
1308 ext2_sync_super(sb, sbi->s_es, 1);
1309
1310 return 0;
1311}
1312
1313static int ext2_unfreeze(struct super_block *sb)
1314{
1315 /* Just write sb to clear EXT2_VALID_FS flag */
1316 ext2_write_super(sb);
1317
1318 return 0;
1319}
1320
1321static void ext2_write_super(struct super_block *sb)
1322{
1323 if (!sb_rdonly(sb))
1324 ext2_sync_fs(sb, 1);
1325}
1326
1327static int ext2_remount (struct super_block * sb, int * flags, char * data)
1328{
1329 struct ext2_sb_info * sbi = EXT2_SB(sb);
1330 struct ext2_super_block * es;
1331 struct ext2_mount_options new_opts;
1332 int err;
1333
1334 sync_filesystem(sb);
1335
1336 spin_lock(&sbi->s_lock);
1337 new_opts.s_mount_opt = sbi->s_mount_opt;
1338 new_opts.s_resuid = sbi->s_resuid;
1339 new_opts.s_resgid = sbi->s_resgid;
1340 spin_unlock(&sbi->s_lock);
1341
1342 if (!parse_options(data, sb, &new_opts))
1343 return -EINVAL;
1344
1345 spin_lock(&sbi->s_lock);
1346 es = sbi->s_es;
1347 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1348 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1349 "dax flag with busy inodes while remounting");
1350 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1351 }
1352 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1353 goto out_set;
1354 if (*flags & SB_RDONLY) {
1355 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1356 !(sbi->s_mount_state & EXT2_VALID_FS))
1357 goto out_set;
1358
1359 /*
1360 * OK, we are remounting a valid rw partition rdonly, so set
1361 * the rdonly flag and then mark the partition as valid again.
1362 */
1363 es->s_state = cpu_to_le16(sbi->s_mount_state);
1364 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1365 spin_unlock(&sbi->s_lock);
1366
1367 err = dquot_suspend(sb, -1);
1368 if (err < 0)
1369 return err;
1370
1371 ext2_sync_super(sb, es, 1);
1372 } else {
1373 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1374 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1375 if (ret) {
1376 spin_unlock(&sbi->s_lock);
1377 ext2_msg(sb, KERN_WARNING,
1378 "warning: couldn't remount RDWR because of "
1379 "unsupported optional features (%x).",
1380 le32_to_cpu(ret));
1381 return -EROFS;
1382 }
1383 /*
1384 * Mounting a RDONLY partition read-write, so reread and
1385 * store the current valid flag. (It may have been changed
1386 * by e2fsck since we originally mounted the partition.)
1387 */
1388 sbi->s_mount_state = le16_to_cpu(es->s_state);
1389 if (!ext2_setup_super (sb, es, 0))
1390 sb->s_flags &= ~SB_RDONLY;
1391 spin_unlock(&sbi->s_lock);
1392
1393 ext2_write_super(sb);
1394
1395 dquot_resume(sb, -1);
1396 }
1397
1398 spin_lock(&sbi->s_lock);
1399out_set:
1400 sbi->s_mount_opt = new_opts.s_mount_opt;
1401 sbi->s_resuid = new_opts.s_resuid;
1402 sbi->s_resgid = new_opts.s_resgid;
1403 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1404 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
1405 spin_unlock(&sbi->s_lock);
1406
1407 return 0;
1408}
1409
1410static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1411{
1412 struct super_block *sb = dentry->d_sb;
1413 struct ext2_sb_info *sbi = EXT2_SB(sb);
1414 struct ext2_super_block *es = sbi->s_es;
1415
1416 spin_lock(&sbi->s_lock);
1417
1418 if (test_opt (sb, MINIX_DF))
1419 sbi->s_overhead_last = 0;
1420 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1421 unsigned long i, overhead = 0;
1422 smp_rmb();
1423
1424 /*
1425 * Compute the overhead (FS structures). This is constant
1426 * for a given filesystem unless the number of block groups
1427 * changes so we cache the previous value until it does.
1428 */
1429
1430 /*
1431 * All of the blocks before first_data_block are
1432 * overhead
1433 */
1434 overhead = le32_to_cpu(es->s_first_data_block);
1435
1436 /*
1437 * Add the overhead attributed to the superblock and
1438 * block group descriptors. If the sparse superblocks
1439 * feature is turned on, then not all groups have this.
1440 */
1441 for (i = 0; i < sbi->s_groups_count; i++)
1442 overhead += ext2_bg_has_super(sb, i) +
1443 ext2_bg_num_gdb(sb, i);
1444
1445 /*
1446 * Every block group has an inode bitmap, a block
1447 * bitmap, and an inode table.
1448 */
1449 overhead += (sbi->s_groups_count *
1450 (2 + sbi->s_itb_per_group));
1451 sbi->s_overhead_last = overhead;
1452 smp_wmb();
1453 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1454 }
1455
1456 buf->f_type = EXT2_SUPER_MAGIC;
1457 buf->f_bsize = sb->s_blocksize;
1458 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1459 buf->f_bfree = ext2_count_free_blocks(sb);
1460 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1461 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1462 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1463 buf->f_bavail = 0;
1464 buf->f_files = le32_to_cpu(es->s_inodes_count);
1465 buf->f_ffree = ext2_count_free_inodes(sb);
1466 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1467 buf->f_namelen = EXT2_NAME_LEN;
1468 buf->f_fsid = uuid_to_fsid(es->s_uuid);
1469 spin_unlock(&sbi->s_lock);
1470 return 0;
1471}
1472
1473static struct dentry *ext2_mount(struct file_system_type *fs_type,
1474 int flags, const char *dev_name, void *data)
1475{
1476 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1477}
1478
1479#ifdef CONFIG_QUOTA
1480
1481/* Read data from quotafile - avoid pagecache and such because we cannot afford
1482 * acquiring the locks... As quota files are never truncated and quota code
1483 * itself serializes the operations (and no one else should touch the files)
1484 * we don't have to be afraid of races */
1485static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1486 size_t len, loff_t off)
1487{
1488 struct inode *inode = sb_dqopt(sb)->files[type];
1489 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1490 int err = 0;
1491 int offset = off & (sb->s_blocksize - 1);
1492 int tocopy;
1493 size_t toread;
1494 struct buffer_head tmp_bh;
1495 struct buffer_head *bh;
1496 loff_t i_size = i_size_read(inode);
1497
1498 if (off > i_size)
1499 return 0;
1500 if (off+len > i_size)
1501 len = i_size-off;
1502 toread = len;
1503 while (toread > 0) {
1504 tocopy = min_t(size_t, 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 */
1529static 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 = min_t(size_t, sb->s_blocksize - offset, towrite);
1543
1544 tmp_bh.b_state = 0;
1545 tmp_bh.b_size = sb->s_blocksize;
1546 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1547 if (err < 0)
1548 goto out;
1549 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1550 bh = sb_bread(sb, tmp_bh.b_blocknr);
1551 else
1552 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1553 if (unlikely(!bh)) {
1554 err = -EIO;
1555 goto out;
1556 }
1557 lock_buffer(bh);
1558 memcpy(bh->b_data+offset, data, tocopy);
1559 flush_dcache_page(bh->b_page);
1560 set_buffer_uptodate(bh);
1561 mark_buffer_dirty(bh);
1562 unlock_buffer(bh);
1563 brelse(bh);
1564 offset = 0;
1565 towrite -= tocopy;
1566 data += tocopy;
1567 blk++;
1568 }
1569out:
1570 if (len == towrite)
1571 return err;
1572 if (inode->i_size < off+len-towrite)
1573 i_size_write(inode, off+len-towrite);
1574 inode_inc_iversion(inode);
1575 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1576 mark_inode_dirty(inode);
1577 return len - towrite;
1578}
1579
1580static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1581 const struct path *path)
1582{
1583 int err;
1584 struct inode *inode;
1585
1586 err = dquot_quota_on(sb, type, format_id, path);
1587 if (err)
1588 return err;
1589
1590 inode = d_inode(path->dentry);
1591 inode_lock(inode);
1592 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1593 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1594 S_NOATIME | S_IMMUTABLE);
1595 inode_unlock(inode);
1596 mark_inode_dirty(inode);
1597
1598 return 0;
1599}
1600
1601static int ext2_quota_off(struct super_block *sb, int type)
1602{
1603 struct inode *inode = sb_dqopt(sb)->files[type];
1604 int err;
1605
1606 if (!inode || !igrab(inode))
1607 goto out;
1608
1609 err = dquot_quota_off(sb, type);
1610 if (err)
1611 goto out_put;
1612
1613 inode_lock(inode);
1614 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1615 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1616 inode_unlock(inode);
1617 mark_inode_dirty(inode);
1618out_put:
1619 iput(inode);
1620 return err;
1621out:
1622 return dquot_quota_off(sb, type);
1623}
1624
1625#endif
1626
1627static struct file_system_type ext2_fs_type = {
1628 .owner = THIS_MODULE,
1629 .name = "ext2",
1630 .mount = ext2_mount,
1631 .kill_sb = kill_block_super,
1632 .fs_flags = FS_REQUIRES_DEV,
1633};
1634MODULE_ALIAS_FS("ext2");
1635
1636static int __init init_ext2_fs(void)
1637{
1638 int err;
1639
1640 err = init_inodecache();
1641 if (err)
1642 return err;
1643 err = register_filesystem(&ext2_fs_type);
1644 if (err)
1645 goto out;
1646 return 0;
1647out:
1648 destroy_inodecache();
1649 return err;
1650}
1651
1652static void __exit exit_ext2_fs(void)
1653{
1654 unregister_filesystem(&ext2_fs_type);
1655 destroy_inodecache();
1656}
1657
1658MODULE_AUTHOR("Remy Card and others");
1659MODULE_DESCRIPTION("Second Extended Filesystem");
1660MODULE_LICENSE("GPL");
1661module_init(init_ext2_fs)
1662module_exit(exit_ext2_fs)
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#include "xip.h"
39
40static void ext2_sync_super(struct super_block *sb,
41 struct ext2_super_block *es, int wait);
42static int ext2_remount (struct super_block * sb, int * flags, char * data);
43static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
44static int ext2_sync_fs(struct super_block *sb, int wait);
45
46void ext2_error(struct super_block *sb, const char *function,
47 const char *fmt, ...)
48{
49 struct va_format vaf;
50 va_list args;
51 struct ext2_sb_info *sbi = EXT2_SB(sb);
52 struct ext2_super_block *es = sbi->s_es;
53
54 if (!(sb->s_flags & MS_RDONLY)) {
55 spin_lock(&sbi->s_lock);
56 sbi->s_mount_state |= EXT2_ERROR_FS;
57 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
58 spin_unlock(&sbi->s_lock);
59 ext2_sync_super(sb, es, 1);
60 }
61
62 va_start(args, fmt);
63
64 vaf.fmt = fmt;
65 vaf.va = &args;
66
67 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
68 sb->s_id, function, &vaf);
69
70 va_end(args);
71
72 if (test_opt(sb, ERRORS_PANIC))
73 panic("EXT2-fs: panic from previous error\n");
74 if (test_opt(sb, ERRORS_RO)) {
75 ext2_msg(sb, KERN_CRIT,
76 "error: remounting filesystem read-only");
77 sb->s_flags |= MS_RDONLY;
78 }
79}
80
81void ext2_msg(struct super_block *sb, const char *prefix,
82 const char *fmt, ...)
83{
84 struct va_format vaf;
85 va_list args;
86
87 va_start(args, fmt);
88
89 vaf.fmt = fmt;
90 vaf.va = &args;
91
92 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
93
94 va_end(args);
95}
96
97/*
98 * This must be called with sbi->s_lock held.
99 */
100void ext2_update_dynamic_rev(struct super_block *sb)
101{
102 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
103
104 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
105 return;
106
107 ext2_msg(sb, KERN_WARNING,
108 "warning: updating to rev %d because of "
109 "new feature flag, running e2fsck is recommended",
110 EXT2_DYNAMIC_REV);
111
112 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
113 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
114 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
115 /* leave es->s_feature_*compat flags alone */
116 /* es->s_uuid will be set by e2fsck if empty */
117
118 /*
119 * The rest of the superblock fields should be zero, and if not it
120 * means they are likely already in use, so leave them alone. We
121 * can leave it up to e2fsck to clean up any inconsistencies there.
122 */
123}
124
125static void ext2_put_super (struct super_block * sb)
126{
127 int db_count;
128 int i;
129 struct ext2_sb_info *sbi = EXT2_SB(sb);
130
131 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
132
133 if (sb->s_dirt)
134 ext2_write_super(sb);
135
136 ext2_xattr_put_super(sb);
137 if (!(sb->s_flags & MS_RDONLY)) {
138 struct ext2_super_block *es = sbi->s_es;
139
140 spin_lock(&sbi->s_lock);
141 es->s_state = cpu_to_le16(sbi->s_mount_state);
142 spin_unlock(&sbi->s_lock);
143 ext2_sync_super(sb, es, 1);
144 }
145 db_count = sbi->s_gdb_count;
146 for (i = 0; i < db_count; i++)
147 if (sbi->s_group_desc[i])
148 brelse (sbi->s_group_desc[i]);
149 kfree(sbi->s_group_desc);
150 kfree(sbi->s_debts);
151 percpu_counter_destroy(&sbi->s_freeblocks_counter);
152 percpu_counter_destroy(&sbi->s_freeinodes_counter);
153 percpu_counter_destroy(&sbi->s_dirs_counter);
154 brelse (sbi->s_sbh);
155 sb->s_fs_info = NULL;
156 kfree(sbi->s_blockgroup_lock);
157 kfree(sbi);
158}
159
160static struct kmem_cache * ext2_inode_cachep;
161
162static struct inode *ext2_alloc_inode(struct super_block *sb)
163{
164 struct ext2_inode_info *ei;
165 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
166 if (!ei)
167 return NULL;
168 ei->i_block_alloc_info = NULL;
169 ei->vfs_inode.i_version = 1;
170 return &ei->vfs_inode;
171}
172
173static void ext2_i_callback(struct rcu_head *head)
174{
175 struct inode *inode = container_of(head, struct inode, i_rcu);
176 INIT_LIST_HEAD(&inode->i_dentry);
177 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
178}
179
180static void ext2_destroy_inode(struct inode *inode)
181{
182 call_rcu(&inode->i_rcu, ext2_i_callback);
183}
184
185static void init_once(void *foo)
186{
187 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
188
189 rwlock_init(&ei->i_meta_lock);
190#ifdef CONFIG_EXT2_FS_XATTR
191 init_rwsem(&ei->xattr_sem);
192#endif
193 mutex_init(&ei->truncate_mutex);
194 inode_init_once(&ei->vfs_inode);
195}
196
197static int init_inodecache(void)
198{
199 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
200 sizeof(struct ext2_inode_info),
201 0, (SLAB_RECLAIM_ACCOUNT|
202 SLAB_MEM_SPREAD),
203 init_once);
204 if (ext2_inode_cachep == NULL)
205 return -ENOMEM;
206 return 0;
207}
208
209static void destroy_inodecache(void)
210{
211 kmem_cache_destroy(ext2_inode_cachep);
212}
213
214static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
215{
216 struct super_block *sb = vfs->mnt_sb;
217 struct ext2_sb_info *sbi = EXT2_SB(sb);
218 struct ext2_super_block *es = sbi->s_es;
219 unsigned long def_mount_opts;
220
221 spin_lock(&sbi->s_lock);
222 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
223
224 if (sbi->s_sb_block != 1)
225 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
226 if (test_opt(sb, MINIX_DF))
227 seq_puts(seq, ",minixdf");
228 if (test_opt(sb, GRPID))
229 seq_puts(seq, ",grpid");
230 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
231 seq_puts(seq, ",nogrpid");
232 if (sbi->s_resuid != EXT2_DEF_RESUID ||
233 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
234 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
235 }
236 if (sbi->s_resgid != EXT2_DEF_RESGID ||
237 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
238 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
239 }
240 if (test_opt(sb, ERRORS_RO)) {
241 int def_errors = le16_to_cpu(es->s_errors);
242
243 if (def_errors == EXT2_ERRORS_PANIC ||
244 def_errors == EXT2_ERRORS_CONTINUE) {
245 seq_puts(seq, ",errors=remount-ro");
246 }
247 }
248 if (test_opt(sb, ERRORS_CONT))
249 seq_puts(seq, ",errors=continue");
250 if (test_opt(sb, ERRORS_PANIC))
251 seq_puts(seq, ",errors=panic");
252 if (test_opt(sb, NO_UID32))
253 seq_puts(seq, ",nouid32");
254 if (test_opt(sb, DEBUG))
255 seq_puts(seq, ",debug");
256 if (test_opt(sb, OLDALLOC))
257 seq_puts(seq, ",oldalloc");
258
259#ifdef CONFIG_EXT2_FS_XATTR
260 if (test_opt(sb, XATTR_USER))
261 seq_puts(seq, ",user_xattr");
262 if (!test_opt(sb, XATTR_USER) &&
263 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
264 seq_puts(seq, ",nouser_xattr");
265 }
266#endif
267
268#ifdef CONFIG_EXT2_FS_POSIX_ACL
269 if (test_opt(sb, POSIX_ACL))
270 seq_puts(seq, ",acl");
271 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
272 seq_puts(seq, ",noacl");
273#endif
274
275 if (test_opt(sb, NOBH))
276 seq_puts(seq, ",nobh");
277
278#if defined(CONFIG_QUOTA)
279 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
280 seq_puts(seq, ",usrquota");
281
282 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
283 seq_puts(seq, ",grpquota");
284#endif
285
286#if defined(CONFIG_EXT2_FS_XIP)
287 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
288 seq_puts(seq, ",xip");
289#endif
290
291 if (!test_opt(sb, RESERVATION))
292 seq_puts(seq, ",noreservation");
293
294 spin_unlock(&sbi->s_lock);
295 return 0;
296}
297
298#ifdef CONFIG_QUOTA
299static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
300static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
301#endif
302
303static const struct super_operations ext2_sops = {
304 .alloc_inode = ext2_alloc_inode,
305 .destroy_inode = ext2_destroy_inode,
306 .write_inode = ext2_write_inode,
307 .evict_inode = ext2_evict_inode,
308 .put_super = ext2_put_super,
309 .write_super = ext2_write_super,
310 .sync_fs = ext2_sync_fs,
311 .statfs = ext2_statfs,
312 .remount_fs = ext2_remount,
313 .show_options = ext2_show_options,
314#ifdef CONFIG_QUOTA
315 .quota_read = ext2_quota_read,
316 .quota_write = ext2_quota_write,
317#endif
318};
319
320static struct inode *ext2_nfs_get_inode(struct super_block *sb,
321 u64 ino, u32 generation)
322{
323 struct inode *inode;
324
325 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
326 return ERR_PTR(-ESTALE);
327 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
328 return ERR_PTR(-ESTALE);
329
330 /* iget isn't really right if the inode is currently unallocated!!
331 * ext2_read_inode currently does appropriate checks, but
332 * it might be "neater" to call ext2_get_inode first and check
333 * if the inode is valid.....
334 */
335 inode = ext2_iget(sb, ino);
336 if (IS_ERR(inode))
337 return ERR_CAST(inode);
338 if (generation && inode->i_generation != generation) {
339 /* we didn't find the right inode.. */
340 iput(inode);
341 return ERR_PTR(-ESTALE);
342 }
343 return inode;
344}
345
346static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
347 int fh_len, int fh_type)
348{
349 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
350 ext2_nfs_get_inode);
351}
352
353static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
354 int fh_len, int fh_type)
355{
356 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
357 ext2_nfs_get_inode);
358}
359
360/* Yes, most of these are left as NULL!!
361 * A NULL value implies the default, which works with ext2-like file
362 * systems, but can be improved upon.
363 * Currently only get_parent is required.
364 */
365static const struct export_operations ext2_export_ops = {
366 .fh_to_dentry = ext2_fh_to_dentry,
367 .fh_to_parent = ext2_fh_to_parent,
368 .get_parent = ext2_get_parent,
369};
370
371static unsigned long get_sb_block(void **data)
372{
373 unsigned long sb_block;
374 char *options = (char *) *data;
375
376 if (!options || strncmp(options, "sb=", 3) != 0)
377 return 1; /* Default location */
378 options += 3;
379 sb_block = simple_strtoul(options, &options, 0);
380 if (*options && *options != ',') {
381 printk("EXT2-fs: Invalid sb specification: %s\n",
382 (char *) *data);
383 return 1;
384 }
385 if (*options == ',')
386 options++;
387 *data = (void *) options;
388 return sb_block;
389}
390
391enum {
392 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
393 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
394 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
395 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
396 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
397 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
398};
399
400static const match_table_t tokens = {
401 {Opt_bsd_df, "bsddf"},
402 {Opt_minix_df, "minixdf"},
403 {Opt_grpid, "grpid"},
404 {Opt_grpid, "bsdgroups"},
405 {Opt_nogrpid, "nogrpid"},
406 {Opt_nogrpid, "sysvgroups"},
407 {Opt_resgid, "resgid=%u"},
408 {Opt_resuid, "resuid=%u"},
409 {Opt_sb, "sb=%u"},
410 {Opt_err_cont, "errors=continue"},
411 {Opt_err_panic, "errors=panic"},
412 {Opt_err_ro, "errors=remount-ro"},
413 {Opt_nouid32, "nouid32"},
414 {Opt_nocheck, "check=none"},
415 {Opt_nocheck, "nocheck"},
416 {Opt_debug, "debug"},
417 {Opt_oldalloc, "oldalloc"},
418 {Opt_orlov, "orlov"},
419 {Opt_nobh, "nobh"},
420 {Opt_user_xattr, "user_xattr"},
421 {Opt_nouser_xattr, "nouser_xattr"},
422 {Opt_acl, "acl"},
423 {Opt_noacl, "noacl"},
424 {Opt_xip, "xip"},
425 {Opt_grpquota, "grpquota"},
426 {Opt_ignore, "noquota"},
427 {Opt_quota, "quota"},
428 {Opt_usrquota, "usrquota"},
429 {Opt_reservation, "reservation"},
430 {Opt_noreservation, "noreservation"},
431 {Opt_err, NULL}
432};
433
434static int parse_options(char *options, struct super_block *sb)
435{
436 char *p;
437 struct ext2_sb_info *sbi = EXT2_SB(sb);
438 substring_t args[MAX_OPT_ARGS];
439 int option;
440
441 if (!options)
442 return 1;
443
444 while ((p = strsep (&options, ",")) != NULL) {
445 int token;
446 if (!*p)
447 continue;
448
449 token = match_token(p, tokens, args);
450 switch (token) {
451 case Opt_bsd_df:
452 clear_opt (sbi->s_mount_opt, MINIX_DF);
453 break;
454 case Opt_minix_df:
455 set_opt (sbi->s_mount_opt, MINIX_DF);
456 break;
457 case Opt_grpid:
458 set_opt (sbi->s_mount_opt, GRPID);
459 break;
460 case Opt_nogrpid:
461 clear_opt (sbi->s_mount_opt, GRPID);
462 break;
463 case Opt_resuid:
464 if (match_int(&args[0], &option))
465 return 0;
466 sbi->s_resuid = option;
467 break;
468 case Opt_resgid:
469 if (match_int(&args[0], &option))
470 return 0;
471 sbi->s_resgid = option;
472 break;
473 case Opt_sb:
474 /* handled by get_sb_block() instead of here */
475 /* *sb_block = match_int(&args[0]); */
476 break;
477 case Opt_err_panic:
478 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
479 clear_opt (sbi->s_mount_opt, ERRORS_RO);
480 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
481 break;
482 case Opt_err_ro:
483 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
484 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
485 set_opt (sbi->s_mount_opt, ERRORS_RO);
486 break;
487 case Opt_err_cont:
488 clear_opt (sbi->s_mount_opt, ERRORS_RO);
489 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
490 set_opt (sbi->s_mount_opt, ERRORS_CONT);
491 break;
492 case Opt_nouid32:
493 set_opt (sbi->s_mount_opt, NO_UID32);
494 break;
495 case Opt_nocheck:
496 clear_opt (sbi->s_mount_opt, CHECK);
497 break;
498 case Opt_debug:
499 set_opt (sbi->s_mount_opt, DEBUG);
500 break;
501 case Opt_oldalloc:
502 set_opt (sbi->s_mount_opt, OLDALLOC);
503 break;
504 case Opt_orlov:
505 clear_opt (sbi->s_mount_opt, OLDALLOC);
506 break;
507 case Opt_nobh:
508 set_opt (sbi->s_mount_opt, NOBH);
509 break;
510#ifdef CONFIG_EXT2_FS_XATTR
511 case Opt_user_xattr:
512 set_opt (sbi->s_mount_opt, XATTR_USER);
513 break;
514 case Opt_nouser_xattr:
515 clear_opt (sbi->s_mount_opt, XATTR_USER);
516 break;
517#else
518 case Opt_user_xattr:
519 case Opt_nouser_xattr:
520 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
521 "not supported");
522 break;
523#endif
524#ifdef CONFIG_EXT2_FS_POSIX_ACL
525 case Opt_acl:
526 set_opt(sbi->s_mount_opt, POSIX_ACL);
527 break;
528 case Opt_noacl:
529 clear_opt(sbi->s_mount_opt, POSIX_ACL);
530 break;
531#else
532 case Opt_acl:
533 case Opt_noacl:
534 ext2_msg(sb, KERN_INFO,
535 "(no)acl options not supported");
536 break;
537#endif
538 case Opt_xip:
539#ifdef CONFIG_EXT2_FS_XIP
540 set_opt (sbi->s_mount_opt, XIP);
541#else
542 ext2_msg(sb, KERN_INFO, "xip option not supported");
543#endif
544 break;
545
546#if defined(CONFIG_QUOTA)
547 case Opt_quota:
548 case Opt_usrquota:
549 set_opt(sbi->s_mount_opt, USRQUOTA);
550 break;
551
552 case Opt_grpquota:
553 set_opt(sbi->s_mount_opt, GRPQUOTA);
554 break;
555#else
556 case Opt_quota:
557 case Opt_usrquota:
558 case Opt_grpquota:
559 ext2_msg(sb, KERN_INFO,
560 "quota operations not supported");
561 break;
562#endif
563
564 case Opt_reservation:
565 set_opt(sbi->s_mount_opt, RESERVATION);
566 ext2_msg(sb, KERN_INFO, "reservations ON");
567 break;
568 case Opt_noreservation:
569 clear_opt(sbi->s_mount_opt, RESERVATION);
570 ext2_msg(sb, KERN_INFO, "reservations OFF");
571 break;
572 case Opt_ignore:
573 break;
574 default:
575 return 0;
576 }
577 }
578 return 1;
579}
580
581static int ext2_setup_super (struct super_block * sb,
582 struct ext2_super_block * es,
583 int read_only)
584{
585 int res = 0;
586 struct ext2_sb_info *sbi = EXT2_SB(sb);
587
588 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
589 ext2_msg(sb, KERN_ERR,
590 "error: revision level too high, "
591 "forcing read-only mode");
592 res = MS_RDONLY;
593 }
594 if (read_only)
595 return res;
596 if (!(sbi->s_mount_state & EXT2_VALID_FS))
597 ext2_msg(sb, KERN_WARNING,
598 "warning: mounting unchecked fs, "
599 "running e2fsck is recommended");
600 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
601 ext2_msg(sb, KERN_WARNING,
602 "warning: mounting fs with errors, "
603 "running e2fsck is recommended");
604 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
605 le16_to_cpu(es->s_mnt_count) >=
606 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
607 ext2_msg(sb, KERN_WARNING,
608 "warning: maximal mount count reached, "
609 "running e2fsck is recommended");
610 else if (le32_to_cpu(es->s_checkinterval) &&
611 (le32_to_cpu(es->s_lastcheck) +
612 le32_to_cpu(es->s_checkinterval) <= get_seconds()))
613 ext2_msg(sb, KERN_WARNING,
614 "warning: checktime reached, "
615 "running e2fsck is recommended");
616 if (!le16_to_cpu(es->s_max_mnt_count))
617 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
618 le16_add_cpu(&es->s_mnt_count, 1);
619 if (test_opt (sb, DEBUG))
620 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
621 "bpg=%lu, ipg=%lu, mo=%04lx]",
622 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
623 sbi->s_frag_size,
624 sbi->s_groups_count,
625 EXT2_BLOCKS_PER_GROUP(sb),
626 EXT2_INODES_PER_GROUP(sb),
627 sbi->s_mount_opt);
628 return res;
629}
630
631static int ext2_check_descriptors(struct super_block *sb)
632{
633 int i;
634 struct ext2_sb_info *sbi = EXT2_SB(sb);
635
636 ext2_debug ("Checking group descriptors");
637
638 for (i = 0; i < sbi->s_groups_count; i++) {
639 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
640 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
641 ext2_fsblk_t last_block;
642
643 if (i == sbi->s_groups_count - 1)
644 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
645 else
646 last_block = first_block +
647 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
648
649 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
650 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
651 {
652 ext2_error (sb, "ext2_check_descriptors",
653 "Block bitmap for group %d"
654 " not in group (block %lu)!",
655 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
656 return 0;
657 }
658 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
659 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
660 {
661 ext2_error (sb, "ext2_check_descriptors",
662 "Inode bitmap for group %d"
663 " not in group (block %lu)!",
664 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
665 return 0;
666 }
667 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
668 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
669 last_block)
670 {
671 ext2_error (sb, "ext2_check_descriptors",
672 "Inode table for group %d"
673 " not in group (block %lu)!",
674 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
675 return 0;
676 }
677 }
678 return 1;
679}
680
681/*
682 * Maximal file size. There is a direct, and {,double-,triple-}indirect
683 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
684 * We need to be 1 filesystem block less than the 2^32 sector limit.
685 */
686static loff_t ext2_max_size(int bits)
687{
688 loff_t res = EXT2_NDIR_BLOCKS;
689 int meta_blocks;
690 loff_t upper_limit;
691
692 /* This is calculated to be the largest file size for a
693 * dense, file such that the total number of
694 * sectors in the file, including data and all indirect blocks,
695 * does not exceed 2^32 -1
696 * __u32 i_blocks representing the total number of
697 * 512 bytes blocks of the file
698 */
699 upper_limit = (1LL << 32) - 1;
700
701 /* total blocks in file system block size */
702 upper_limit >>= (bits - 9);
703
704
705 /* indirect blocks */
706 meta_blocks = 1;
707 /* double indirect blocks */
708 meta_blocks += 1 + (1LL << (bits-2));
709 /* tripple indirect blocks */
710 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
711
712 upper_limit -= meta_blocks;
713 upper_limit <<= bits;
714
715 res += 1LL << (bits-2);
716 res += 1LL << (2*(bits-2));
717 res += 1LL << (3*(bits-2));
718 res <<= bits;
719 if (res > upper_limit)
720 res = upper_limit;
721
722 if (res > MAX_LFS_FILESIZE)
723 res = MAX_LFS_FILESIZE;
724
725 return res;
726}
727
728static unsigned long descriptor_loc(struct super_block *sb,
729 unsigned long logic_sb_block,
730 int nr)
731{
732 struct ext2_sb_info *sbi = EXT2_SB(sb);
733 unsigned long bg, first_meta_bg;
734 int has_super = 0;
735
736 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
737
738 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
739 nr < first_meta_bg)
740 return (logic_sb_block + nr + 1);
741 bg = sbi->s_desc_per_block * nr;
742 if (ext2_bg_has_super(sb, bg))
743 has_super = 1;
744
745 return ext2_group_first_block_no(sb, bg) + has_super;
746}
747
748static int ext2_fill_super(struct super_block *sb, void *data, int silent)
749{
750 struct buffer_head * bh;
751 struct ext2_sb_info * sbi;
752 struct ext2_super_block * es;
753 struct inode *root;
754 unsigned long block;
755 unsigned long sb_block = get_sb_block(&data);
756 unsigned long logic_sb_block;
757 unsigned long offset = 0;
758 unsigned long def_mount_opts;
759 long ret = -EINVAL;
760 int blocksize = BLOCK_SIZE;
761 int db_count;
762 int i, j;
763 __le32 features;
764 int err;
765
766 err = -ENOMEM;
767 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
768 if (!sbi)
769 goto failed_unlock;
770
771 sbi->s_blockgroup_lock =
772 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
773 if (!sbi->s_blockgroup_lock) {
774 kfree(sbi);
775 goto failed_unlock;
776 }
777 sb->s_fs_info = sbi;
778 sbi->s_sb_block = sb_block;
779
780 spin_lock_init(&sbi->s_lock);
781
782 /*
783 * See what the current blocksize for the device is, and
784 * use that as the blocksize. Otherwise (or if the blocksize
785 * is smaller than the default) use the default.
786 * This is important for devices that have a hardware
787 * sectorsize that is larger than the default.
788 */
789 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
790 if (!blocksize) {
791 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
792 goto failed_sbi;
793 }
794
795 /*
796 * If the superblock doesn't start on a hardware sector boundary,
797 * calculate the offset.
798 */
799 if (blocksize != BLOCK_SIZE) {
800 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
801 offset = (sb_block*BLOCK_SIZE) % blocksize;
802 } else {
803 logic_sb_block = sb_block;
804 }
805
806 if (!(bh = sb_bread(sb, logic_sb_block))) {
807 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
808 goto failed_sbi;
809 }
810 /*
811 * Note: s_es must be initialized as soon as possible because
812 * some ext2 macro-instructions depend on its value
813 */
814 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
815 sbi->s_es = es;
816 sb->s_magic = le16_to_cpu(es->s_magic);
817
818 if (sb->s_magic != EXT2_SUPER_MAGIC)
819 goto cantfind_ext2;
820
821 /* Set defaults before we parse the mount options */
822 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
823 if (def_mount_opts & EXT2_DEFM_DEBUG)
824 set_opt(sbi->s_mount_opt, DEBUG);
825 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
826 set_opt(sbi->s_mount_opt, GRPID);
827 if (def_mount_opts & EXT2_DEFM_UID16)
828 set_opt(sbi->s_mount_opt, NO_UID32);
829#ifdef CONFIG_EXT2_FS_XATTR
830 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
831 set_opt(sbi->s_mount_opt, XATTR_USER);
832#endif
833#ifdef CONFIG_EXT2_FS_POSIX_ACL
834 if (def_mount_opts & EXT2_DEFM_ACL)
835 set_opt(sbi->s_mount_opt, POSIX_ACL);
836#endif
837
838 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
839 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
840 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
841 set_opt(sbi->s_mount_opt, ERRORS_CONT);
842 else
843 set_opt(sbi->s_mount_opt, ERRORS_RO);
844
845 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
846 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
847
848 set_opt(sbi->s_mount_opt, RESERVATION);
849
850 if (!parse_options((char *) data, sb))
851 goto failed_mount;
852
853 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
854 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
855 MS_POSIXACL : 0);
856
857 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
858 EXT2_MOUNT_XIP if not */
859
860 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
861 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
862 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
863 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
864 ext2_msg(sb, KERN_WARNING,
865 "warning: feature flags set on rev 0 fs, "
866 "running e2fsck is recommended");
867 /*
868 * Check feature flags regardless of the revision level, since we
869 * previously didn't change the revision level when setting the flags,
870 * so there is a chance incompat flags are set on a rev 0 filesystem.
871 */
872 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
873 if (features) {
874 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
875 "unsupported optional features (%x)",
876 le32_to_cpu(features));
877 goto failed_mount;
878 }
879 if (!(sb->s_flags & MS_RDONLY) &&
880 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
881 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
882 "unsupported optional features (%x)",
883 le32_to_cpu(features));
884 goto failed_mount;
885 }
886
887 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
888
889 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) {
890 if (!silent)
891 ext2_msg(sb, KERN_ERR,
892 "error: unsupported blocksize for xip");
893 goto failed_mount;
894 }
895
896 /* If the blocksize doesn't match, re-read the thing.. */
897 if (sb->s_blocksize != blocksize) {
898 brelse(bh);
899
900 if (!sb_set_blocksize(sb, blocksize)) {
901 ext2_msg(sb, KERN_ERR,
902 "error: bad blocksize %d", blocksize);
903 goto failed_sbi;
904 }
905
906 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
907 offset = (sb_block*BLOCK_SIZE) % blocksize;
908 bh = sb_bread(sb, logic_sb_block);
909 if(!bh) {
910 ext2_msg(sb, KERN_ERR, "error: couldn't read"
911 "superblock on 2nd try");
912 goto failed_sbi;
913 }
914 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
915 sbi->s_es = es;
916 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
917 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
918 goto failed_mount;
919 }
920 }
921
922 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
923
924 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
925 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
926 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
927 } else {
928 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
929 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
930 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
931 !is_power_of_2(sbi->s_inode_size) ||
932 (sbi->s_inode_size > blocksize)) {
933 ext2_msg(sb, KERN_ERR,
934 "error: unsupported inode size: %d",
935 sbi->s_inode_size);
936 goto failed_mount;
937 }
938 }
939
940 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
941 le32_to_cpu(es->s_log_frag_size);
942 if (sbi->s_frag_size == 0)
943 goto cantfind_ext2;
944 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
945
946 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
947 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
948 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
949
950 if (EXT2_INODE_SIZE(sb) == 0)
951 goto cantfind_ext2;
952 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
953 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
954 goto cantfind_ext2;
955 sbi->s_itb_per_group = sbi->s_inodes_per_group /
956 sbi->s_inodes_per_block;
957 sbi->s_desc_per_block = sb->s_blocksize /
958 sizeof (struct ext2_group_desc);
959 sbi->s_sbh = bh;
960 sbi->s_mount_state = le16_to_cpu(es->s_state);
961 sbi->s_addr_per_block_bits =
962 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
963 sbi->s_desc_per_block_bits =
964 ilog2 (EXT2_DESC_PER_BLOCK(sb));
965
966 if (sb->s_magic != EXT2_SUPER_MAGIC)
967 goto cantfind_ext2;
968
969 if (sb->s_blocksize != bh->b_size) {
970 if (!silent)
971 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
972 goto failed_mount;
973 }
974
975 if (sb->s_blocksize != sbi->s_frag_size) {
976 ext2_msg(sb, KERN_ERR,
977 "error: fragsize %lu != blocksize %lu"
978 "(not supported yet)",
979 sbi->s_frag_size, sb->s_blocksize);
980 goto failed_mount;
981 }
982
983 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
984 ext2_msg(sb, KERN_ERR,
985 "error: #blocks per group too big: %lu",
986 sbi->s_blocks_per_group);
987 goto failed_mount;
988 }
989 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
990 ext2_msg(sb, KERN_ERR,
991 "error: #fragments per group too big: %lu",
992 sbi->s_frags_per_group);
993 goto failed_mount;
994 }
995 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
996 ext2_msg(sb, KERN_ERR,
997 "error: #inodes per group too big: %lu",
998 sbi->s_inodes_per_group);
999 goto failed_mount;
1000 }
1001
1002 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1003 goto cantfind_ext2;
1004 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1005 le32_to_cpu(es->s_first_data_block) - 1)
1006 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1007 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1008 EXT2_DESC_PER_BLOCK(sb);
1009 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
1010 if (sbi->s_group_desc == NULL) {
1011 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1012 goto failed_mount;
1013 }
1014 bgl_lock_init(sbi->s_blockgroup_lock);
1015 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1016 if (!sbi->s_debts) {
1017 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1018 goto failed_mount_group_desc;
1019 }
1020 for (i = 0; i < db_count; i++) {
1021 block = descriptor_loc(sb, logic_sb_block, i);
1022 sbi->s_group_desc[i] = sb_bread(sb, block);
1023 if (!sbi->s_group_desc[i]) {
1024 for (j = 0; j < i; j++)
1025 brelse (sbi->s_group_desc[j]);
1026 ext2_msg(sb, KERN_ERR,
1027 "error: unable to read group descriptors");
1028 goto failed_mount_group_desc;
1029 }
1030 }
1031 if (!ext2_check_descriptors (sb)) {
1032 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1033 goto failed_mount2;
1034 }
1035 sbi->s_gdb_count = db_count;
1036 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1037 spin_lock_init(&sbi->s_next_gen_lock);
1038
1039 /* per fileystem reservation list head & lock */
1040 spin_lock_init(&sbi->s_rsv_window_lock);
1041 sbi->s_rsv_window_root = RB_ROOT;
1042 /*
1043 * Add a single, static dummy reservation to the start of the
1044 * reservation window list --- it gives us a placeholder for
1045 * append-at-start-of-list which makes the allocation logic
1046 * _much_ simpler.
1047 */
1048 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1049 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1050 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1051 sbi->s_rsv_window_head.rsv_goal_size = 0;
1052 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1053
1054 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1055 ext2_count_free_blocks(sb));
1056 if (!err) {
1057 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1058 ext2_count_free_inodes(sb));
1059 }
1060 if (!err) {
1061 err = percpu_counter_init(&sbi->s_dirs_counter,
1062 ext2_count_dirs(sb));
1063 }
1064 if (err) {
1065 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1066 goto failed_mount3;
1067 }
1068 /*
1069 * set up enough so that it can read an inode
1070 */
1071 sb->s_op = &ext2_sops;
1072 sb->s_export_op = &ext2_export_ops;
1073 sb->s_xattr = ext2_xattr_handlers;
1074
1075#ifdef CONFIG_QUOTA
1076 sb->dq_op = &dquot_operations;
1077 sb->s_qcop = &dquot_quotactl_ops;
1078#endif
1079
1080 root = ext2_iget(sb, EXT2_ROOT_INO);
1081 if (IS_ERR(root)) {
1082 ret = PTR_ERR(root);
1083 goto failed_mount3;
1084 }
1085 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1086 iput(root);
1087 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1088 goto failed_mount3;
1089 }
1090
1091 sb->s_root = d_alloc_root(root);
1092 if (!sb->s_root) {
1093 iput(root);
1094 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1095 ret = -ENOMEM;
1096 goto failed_mount3;
1097 }
1098 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1099 ext2_msg(sb, KERN_WARNING,
1100 "warning: mounting ext3 filesystem as ext2");
1101 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY))
1102 sb->s_flags |= MS_RDONLY;
1103 ext2_write_super(sb);
1104 return 0;
1105
1106cantfind_ext2:
1107 if (!silent)
1108 ext2_msg(sb, KERN_ERR,
1109 "error: can't find an ext2 filesystem on dev %s.",
1110 sb->s_id);
1111 goto failed_mount;
1112failed_mount3:
1113 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1114 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1115 percpu_counter_destroy(&sbi->s_dirs_counter);
1116failed_mount2:
1117 for (i = 0; i < db_count; i++)
1118 brelse(sbi->s_group_desc[i]);
1119failed_mount_group_desc:
1120 kfree(sbi->s_group_desc);
1121 kfree(sbi->s_debts);
1122failed_mount:
1123 brelse(bh);
1124failed_sbi:
1125 sb->s_fs_info = NULL;
1126 kfree(sbi->s_blockgroup_lock);
1127 kfree(sbi);
1128failed_unlock:
1129 return ret;
1130}
1131
1132static void ext2_clear_super_error(struct super_block *sb)
1133{
1134 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1135
1136 if (buffer_write_io_error(sbh)) {
1137 /*
1138 * Oh, dear. A previous attempt to write the
1139 * superblock failed. This could happen because the
1140 * USB device was yanked out. Or it could happen to
1141 * be a transient write error and maybe the block will
1142 * be remapped. Nothing we can do but to retry the
1143 * write and hope for the best.
1144 */
1145 ext2_msg(sb, KERN_ERR,
1146 "previous I/O error to superblock detected\n");
1147 clear_buffer_write_io_error(sbh);
1148 set_buffer_uptodate(sbh);
1149 }
1150}
1151
1152static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1153 int wait)
1154{
1155 ext2_clear_super_error(sb);
1156 spin_lock(&EXT2_SB(sb)->s_lock);
1157 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1158 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1159 es->s_wtime = cpu_to_le32(get_seconds());
1160 /* unlock before we do IO */
1161 spin_unlock(&EXT2_SB(sb)->s_lock);
1162 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1163 if (wait)
1164 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1165 sb->s_dirt = 0;
1166}
1167
1168/*
1169 * In the second extended file system, it is not necessary to
1170 * write the super block since we use a mapping of the
1171 * disk super block in a buffer.
1172 *
1173 * However, this function is still used to set the fs valid
1174 * flags to 0. We need to set this flag to 0 since the fs
1175 * may have been checked while mounted and e2fsck may have
1176 * set s_state to EXT2_VALID_FS after some corrections.
1177 */
1178static int ext2_sync_fs(struct super_block *sb, int wait)
1179{
1180 struct ext2_sb_info *sbi = EXT2_SB(sb);
1181 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1182
1183 spin_lock(&sbi->s_lock);
1184 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1185 ext2_debug("setting valid to 0\n");
1186 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1187 }
1188 spin_unlock(&sbi->s_lock);
1189 ext2_sync_super(sb, es, wait);
1190 return 0;
1191}
1192
1193
1194void ext2_write_super(struct super_block *sb)
1195{
1196 if (!(sb->s_flags & MS_RDONLY))
1197 ext2_sync_fs(sb, 1);
1198 else
1199 sb->s_dirt = 0;
1200}
1201
1202static int ext2_remount (struct super_block * sb, int * flags, char * data)
1203{
1204 struct ext2_sb_info * sbi = EXT2_SB(sb);
1205 struct ext2_super_block * es;
1206 unsigned long old_mount_opt = sbi->s_mount_opt;
1207 struct ext2_mount_options old_opts;
1208 unsigned long old_sb_flags;
1209 int err;
1210
1211 spin_lock(&sbi->s_lock);
1212
1213 /* Store the old options */
1214 old_sb_flags = sb->s_flags;
1215 old_opts.s_mount_opt = sbi->s_mount_opt;
1216 old_opts.s_resuid = sbi->s_resuid;
1217 old_opts.s_resgid = sbi->s_resgid;
1218
1219 /*
1220 * Allow the "check" option to be passed as a remount option.
1221 */
1222 if (!parse_options(data, sb)) {
1223 err = -EINVAL;
1224 goto restore_opts;
1225 }
1226
1227 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1228 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1229
1230 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
1231 EXT2_MOUNT_XIP if not */
1232
1233 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) {
1234 ext2_msg(sb, KERN_WARNING,
1235 "warning: unsupported blocksize for xip");
1236 err = -EINVAL;
1237 goto restore_opts;
1238 }
1239
1240 es = sbi->s_es;
1241 if ((sbi->s_mount_opt ^ old_mount_opt) & EXT2_MOUNT_XIP) {
1242 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1243 "xip flag with busy inodes while remounting");
1244 sbi->s_mount_opt &= ~EXT2_MOUNT_XIP;
1245 sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP;
1246 }
1247 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
1248 spin_unlock(&sbi->s_lock);
1249 return 0;
1250 }
1251 if (*flags & MS_RDONLY) {
1252 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1253 !(sbi->s_mount_state & EXT2_VALID_FS)) {
1254 spin_unlock(&sbi->s_lock);
1255 return 0;
1256 }
1257
1258 /*
1259 * OK, we are remounting a valid rw partition rdonly, so set
1260 * the rdonly flag and then mark the partition as valid again.
1261 */
1262 es->s_state = cpu_to_le16(sbi->s_mount_state);
1263 es->s_mtime = cpu_to_le32(get_seconds());
1264 spin_unlock(&sbi->s_lock);
1265
1266 err = dquot_suspend(sb, -1);
1267 if (err < 0) {
1268 spin_lock(&sbi->s_lock);
1269 goto restore_opts;
1270 }
1271
1272 ext2_sync_super(sb, es, 1);
1273 } else {
1274 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1275 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1276 if (ret) {
1277 ext2_msg(sb, KERN_WARNING,
1278 "warning: couldn't remount RDWR because of "
1279 "unsupported optional features (%x).",
1280 le32_to_cpu(ret));
1281 err = -EROFS;
1282 goto restore_opts;
1283 }
1284 /*
1285 * Mounting a RDONLY partition read-write, so reread and
1286 * store the current valid flag. (It may have been changed
1287 * by e2fsck since we originally mounted the partition.)
1288 */
1289 sbi->s_mount_state = le16_to_cpu(es->s_state);
1290 if (!ext2_setup_super (sb, es, 0))
1291 sb->s_flags &= ~MS_RDONLY;
1292 spin_unlock(&sbi->s_lock);
1293
1294 ext2_write_super(sb);
1295
1296 dquot_resume(sb, -1);
1297 }
1298
1299 return 0;
1300restore_opts:
1301 sbi->s_mount_opt = old_opts.s_mount_opt;
1302 sbi->s_resuid = old_opts.s_resuid;
1303 sbi->s_resgid = old_opts.s_resgid;
1304 sb->s_flags = old_sb_flags;
1305 spin_unlock(&sbi->s_lock);
1306 return err;
1307}
1308
1309static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1310{
1311 struct super_block *sb = dentry->d_sb;
1312 struct ext2_sb_info *sbi = EXT2_SB(sb);
1313 struct ext2_super_block *es = sbi->s_es;
1314 u64 fsid;
1315
1316 spin_lock(&sbi->s_lock);
1317
1318 if (test_opt (sb, MINIX_DF))
1319 sbi->s_overhead_last = 0;
1320 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1321 unsigned long i, overhead = 0;
1322 smp_rmb();
1323
1324 /*
1325 * Compute the overhead (FS structures). This is constant
1326 * for a given filesystem unless the number of block groups
1327 * changes so we cache the previous value until it does.
1328 */
1329
1330 /*
1331 * All of the blocks before first_data_block are
1332 * overhead
1333 */
1334 overhead = le32_to_cpu(es->s_first_data_block);
1335
1336 /*
1337 * Add the overhead attributed to the superblock and
1338 * block group descriptors. If the sparse superblocks
1339 * feature is turned on, then not all groups have this.
1340 */
1341 for (i = 0; i < sbi->s_groups_count; i++)
1342 overhead += ext2_bg_has_super(sb, i) +
1343 ext2_bg_num_gdb(sb, i);
1344
1345 /*
1346 * Every block group has an inode bitmap, a block
1347 * bitmap, and an inode table.
1348 */
1349 overhead += (sbi->s_groups_count *
1350 (2 + sbi->s_itb_per_group));
1351 sbi->s_overhead_last = overhead;
1352 smp_wmb();
1353 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1354 }
1355
1356 buf->f_type = EXT2_SUPER_MAGIC;
1357 buf->f_bsize = sb->s_blocksize;
1358 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1359 buf->f_bfree = ext2_count_free_blocks(sb);
1360 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1361 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1362 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1363 buf->f_bavail = 0;
1364 buf->f_files = le32_to_cpu(es->s_inodes_count);
1365 buf->f_ffree = ext2_count_free_inodes(sb);
1366 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1367 buf->f_namelen = EXT2_NAME_LEN;
1368 fsid = le64_to_cpup((void *)es->s_uuid) ^
1369 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1370 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1371 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1372 spin_unlock(&sbi->s_lock);
1373 return 0;
1374}
1375
1376static struct dentry *ext2_mount(struct file_system_type *fs_type,
1377 int flags, const char *dev_name, void *data)
1378{
1379 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1380}
1381
1382#ifdef CONFIG_QUOTA
1383
1384/* Read data from quotafile - avoid pagecache and such because we cannot afford
1385 * acquiring the locks... As quota files are never truncated and quota code
1386 * itself serializes the operations (and no one else should touch the files)
1387 * we don't have to be afraid of races */
1388static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1389 size_t len, loff_t off)
1390{
1391 struct inode *inode = sb_dqopt(sb)->files[type];
1392 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1393 int err = 0;
1394 int offset = off & (sb->s_blocksize - 1);
1395 int tocopy;
1396 size_t toread;
1397 struct buffer_head tmp_bh;
1398 struct buffer_head *bh;
1399 loff_t i_size = i_size_read(inode);
1400
1401 if (off > i_size)
1402 return 0;
1403 if (off+len > i_size)
1404 len = i_size-off;
1405 toread = len;
1406 while (toread > 0) {
1407 tocopy = sb->s_blocksize - offset < toread ?
1408 sb->s_blocksize - offset : toread;
1409
1410 tmp_bh.b_state = 0;
1411 tmp_bh.b_size = sb->s_blocksize;
1412 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1413 if (err < 0)
1414 return err;
1415 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1416 memset(data, 0, tocopy);
1417 else {
1418 bh = sb_bread(sb, tmp_bh.b_blocknr);
1419 if (!bh)
1420 return -EIO;
1421 memcpy(data, bh->b_data+offset, tocopy);
1422 brelse(bh);
1423 }
1424 offset = 0;
1425 toread -= tocopy;
1426 data += tocopy;
1427 blk++;
1428 }
1429 return len;
1430}
1431
1432/* Write to quotafile */
1433static ssize_t ext2_quota_write(struct super_block *sb, int type,
1434 const char *data, size_t len, loff_t off)
1435{
1436 struct inode *inode = sb_dqopt(sb)->files[type];
1437 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1438 int err = 0;
1439 int offset = off & (sb->s_blocksize - 1);
1440 int tocopy;
1441 size_t towrite = len;
1442 struct buffer_head tmp_bh;
1443 struct buffer_head *bh;
1444
1445 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1446 while (towrite > 0) {
1447 tocopy = sb->s_blocksize - offset < towrite ?
1448 sb->s_blocksize - offset : towrite;
1449
1450 tmp_bh.b_state = 0;
1451 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1452 if (err < 0)
1453 goto out;
1454 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1455 bh = sb_bread(sb, tmp_bh.b_blocknr);
1456 else
1457 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1458 if (!bh) {
1459 err = -EIO;
1460 goto out;
1461 }
1462 lock_buffer(bh);
1463 memcpy(bh->b_data+offset, data, tocopy);
1464 flush_dcache_page(bh->b_page);
1465 set_buffer_uptodate(bh);
1466 mark_buffer_dirty(bh);
1467 unlock_buffer(bh);
1468 brelse(bh);
1469 offset = 0;
1470 towrite -= tocopy;
1471 data += tocopy;
1472 blk++;
1473 }
1474out:
1475 if (len == towrite) {
1476 mutex_unlock(&inode->i_mutex);
1477 return err;
1478 }
1479 if (inode->i_size < off+len-towrite)
1480 i_size_write(inode, off+len-towrite);
1481 inode->i_version++;
1482 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1483 mark_inode_dirty(inode);
1484 mutex_unlock(&inode->i_mutex);
1485 return len - towrite;
1486}
1487
1488#endif
1489
1490static struct file_system_type ext2_fs_type = {
1491 .owner = THIS_MODULE,
1492 .name = "ext2",
1493 .mount = ext2_mount,
1494 .kill_sb = kill_block_super,
1495 .fs_flags = FS_REQUIRES_DEV,
1496};
1497
1498static int __init init_ext2_fs(void)
1499{
1500 int err = init_ext2_xattr();
1501 if (err)
1502 return err;
1503 err = init_inodecache();
1504 if (err)
1505 goto out1;
1506 err = register_filesystem(&ext2_fs_type);
1507 if (err)
1508 goto out;
1509 return 0;
1510out:
1511 destroy_inodecache();
1512out1:
1513 exit_ext2_xattr();
1514 return err;
1515}
1516
1517static void __exit exit_ext2_fs(void)
1518{
1519 unregister_filesystem(&ext2_fs_type);
1520 destroy_inodecache();
1521 exit_ext2_xattr();
1522}
1523
1524module_init(init_ext2_fs)
1525module_exit(exit_ext2_fs)