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 <linux/uaccess.h>
35 #include <linux/dax.h>
36 #include "ext2.h"
37 #include "xattr.h"
38 #include "acl.h"
39
40 static void ext2_write_super(struct super_block *sb);
41 static int ext2_remount (struct super_block * sb, int * flags, char * data);
42 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
43 static int ext2_sync_fs(struct super_block *sb, int wait);
44 static int ext2_freeze(struct super_block *sb);
45 static int ext2_unfreeze(struct super_block *sb);
46
ext2_error(struct super_block * sb,const char * function,const char * fmt,...)47 void ext2_error(struct super_block *sb, const char *function,
48 const char *fmt, ...)
49 {
50 struct va_format vaf;
51 va_list args;
52 struct ext2_sb_info *sbi = EXT2_SB(sb);
53 struct ext2_super_block *es = sbi->s_es;
54
55 if (!sb_rdonly(sb)) {
56 spin_lock(&sbi->s_lock);
57 sbi->s_mount_state |= EXT2_ERROR_FS;
58 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
59 spin_unlock(&sbi->s_lock);
60 ext2_sync_super(sb, es, 1);
61 }
62
63 va_start(args, fmt);
64
65 vaf.fmt = fmt;
66 vaf.va = &args;
67
68 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
69 sb->s_id, function, &vaf);
70
71 va_end(args);
72
73 if (test_opt(sb, ERRORS_PANIC))
74 panic("EXT2-fs: panic from previous error\n");
75 if (test_opt(sb, ERRORS_RO)) {
76 ext2_msg(sb, KERN_CRIT,
77 "error: remounting filesystem read-only");
78 sb->s_flags |= MS_RDONLY;
79 }
80 }
81
ext2_msg(struct super_block * sb,const char * prefix,const char * fmt,...)82 void ext2_msg(struct super_block *sb, const char *prefix,
83 const char *fmt, ...)
84 {
85 struct va_format vaf;
86 va_list args;
87
88 va_start(args, fmt);
89
90 vaf.fmt = fmt;
91 vaf.va = &args;
92
93 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
94
95 va_end(args);
96 }
97
98 /*
99 * This must be called with sbi->s_lock held.
100 */
ext2_update_dynamic_rev(struct super_block * sb)101 void ext2_update_dynamic_rev(struct super_block *sb)
102 {
103 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
104
105 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
106 return;
107
108 ext2_msg(sb, KERN_WARNING,
109 "warning: updating to rev %d because of "
110 "new feature flag, running e2fsck is recommended",
111 EXT2_DYNAMIC_REV);
112
113 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
114 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
115 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
116 /* leave es->s_feature_*compat flags alone */
117 /* es->s_uuid will be set by e2fsck if empty */
118
119 /*
120 * The rest of the superblock fields should be zero, and if not it
121 * means they are likely already in use, so leave them alone. We
122 * can leave it up to e2fsck to clean up any inconsistencies there.
123 */
124 }
125
126 #ifdef CONFIG_QUOTA
127 static int ext2_quota_off(struct super_block *sb, int type);
128
ext2_quota_off_umount(struct super_block * sb)129 static void ext2_quota_off_umount(struct super_block *sb)
130 {
131 int type;
132
133 for (type = 0; type < MAXQUOTAS; type++)
134 ext2_quota_off(sb, type);
135 }
136 #else
ext2_quota_off_umount(struct super_block * sb)137 static inline void ext2_quota_off_umount(struct super_block *sb)
138 {
139 }
140 #endif
141
ext2_put_super(struct super_block * sb)142 static void ext2_put_super (struct super_block * sb)
143 {
144 int db_count;
145 int i;
146 struct ext2_sb_info *sbi = EXT2_SB(sb);
147
148 ext2_quota_off_umount(sb);
149
150 if (sbi->s_ea_block_cache) {
151 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
152 sbi->s_ea_block_cache = NULL;
153 }
154 if (!sb_rdonly(sb)) {
155 struct ext2_super_block *es = sbi->s_es;
156
157 spin_lock(&sbi->s_lock);
158 es->s_state = cpu_to_le16(sbi->s_mount_state);
159 spin_unlock(&sbi->s_lock);
160 ext2_sync_super(sb, es, 1);
161 }
162 db_count = sbi->s_gdb_count;
163 for (i = 0; i < db_count; i++)
164 if (sbi->s_group_desc[i])
165 brelse (sbi->s_group_desc[i]);
166 kfree(sbi->s_group_desc);
167 kfree(sbi->s_debts);
168 percpu_counter_destroy(&sbi->s_freeblocks_counter);
169 percpu_counter_destroy(&sbi->s_freeinodes_counter);
170 percpu_counter_destroy(&sbi->s_dirs_counter);
171 brelse (sbi->s_sbh);
172 sb->s_fs_info = NULL;
173 kfree(sbi->s_blockgroup_lock);
174 fs_put_dax(sbi->s_daxdev);
175 kfree(sbi);
176 }
177
178 static struct kmem_cache * ext2_inode_cachep;
179
ext2_alloc_inode(struct super_block * sb)180 static struct inode *ext2_alloc_inode(struct super_block *sb)
181 {
182 struct ext2_inode_info *ei;
183 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
184 if (!ei)
185 return NULL;
186 ei->i_block_alloc_info = NULL;
187 ei->vfs_inode.i_version = 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
ext2_i_callback(struct rcu_head * head)195 static void ext2_i_callback(struct rcu_head *head)
196 {
197 struct inode *inode = container_of(head, struct inode, i_rcu);
198 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
199 }
200
ext2_destroy_inode(struct inode * inode)201 static void ext2_destroy_inode(struct inode *inode)
202 {
203 call_rcu(&inode->i_rcu, ext2_i_callback);
204 }
205
init_once(void * foo)206 static void init_once(void *foo)
207 {
208 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
209
210 rwlock_init(&ei->i_meta_lock);
211 #ifdef CONFIG_EXT2_FS_XATTR
212 init_rwsem(&ei->xattr_sem);
213 #endif
214 mutex_init(&ei->truncate_mutex);
215 #ifdef CONFIG_FS_DAX
216 init_rwsem(&ei->dax_sem);
217 #endif
218 inode_init_once(&ei->vfs_inode);
219 }
220
init_inodecache(void)221 static int __init init_inodecache(void)
222 {
223 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
224 sizeof(struct ext2_inode_info),
225 0, (SLAB_RECLAIM_ACCOUNT|
226 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
227 init_once);
228 if (ext2_inode_cachep == NULL)
229 return -ENOMEM;
230 return 0;
231 }
232
destroy_inodecache(void)233 static void destroy_inodecache(void)
234 {
235 /*
236 * Make sure all delayed rcu free inodes are flushed before we
237 * destroy cache.
238 */
239 rcu_barrier();
240 kmem_cache_destroy(ext2_inode_cachep);
241 }
242
ext2_show_options(struct seq_file * seq,struct dentry * root)243 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
244 {
245 struct super_block *sb = root->d_sb;
246 struct ext2_sb_info *sbi = EXT2_SB(sb);
247 struct ext2_super_block *es = sbi->s_es;
248 unsigned long def_mount_opts;
249
250 spin_lock(&sbi->s_lock);
251 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
252
253 if (sbi->s_sb_block != 1)
254 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
255 if (test_opt(sb, MINIX_DF))
256 seq_puts(seq, ",minixdf");
257 if (test_opt(sb, GRPID))
258 seq_puts(seq, ",grpid");
259 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
260 seq_puts(seq, ",nogrpid");
261 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
262 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
263 seq_printf(seq, ",resuid=%u",
264 from_kuid_munged(&init_user_ns, sbi->s_resuid));
265 }
266 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
267 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
268 seq_printf(seq, ",resgid=%u",
269 from_kgid_munged(&init_user_ns, sbi->s_resgid));
270 }
271 if (test_opt(sb, ERRORS_RO)) {
272 int def_errors = le16_to_cpu(es->s_errors);
273
274 if (def_errors == EXT2_ERRORS_PANIC ||
275 def_errors == EXT2_ERRORS_CONTINUE) {
276 seq_puts(seq, ",errors=remount-ro");
277 }
278 }
279 if (test_opt(sb, ERRORS_CONT))
280 seq_puts(seq, ",errors=continue");
281 if (test_opt(sb, ERRORS_PANIC))
282 seq_puts(seq, ",errors=panic");
283 if (test_opt(sb, NO_UID32))
284 seq_puts(seq, ",nouid32");
285 if (test_opt(sb, DEBUG))
286 seq_puts(seq, ",debug");
287 if (test_opt(sb, OLDALLOC))
288 seq_puts(seq, ",oldalloc");
289
290 #ifdef CONFIG_EXT2_FS_XATTR
291 if (test_opt(sb, XATTR_USER))
292 seq_puts(seq, ",user_xattr");
293 if (!test_opt(sb, XATTR_USER) &&
294 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
295 seq_puts(seq, ",nouser_xattr");
296 }
297 #endif
298
299 #ifdef CONFIG_EXT2_FS_POSIX_ACL
300 if (test_opt(sb, POSIX_ACL))
301 seq_puts(seq, ",acl");
302 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
303 seq_puts(seq, ",noacl");
304 #endif
305
306 if (test_opt(sb, NOBH))
307 seq_puts(seq, ",nobh");
308
309 #if defined(CONFIG_QUOTA)
310 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
311 seq_puts(seq, ",usrquota");
312
313 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
314 seq_puts(seq, ",grpquota");
315 #endif
316
317 #ifdef CONFIG_FS_DAX
318 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
319 seq_puts(seq, ",xip");
320 if (sbi->s_mount_opt & EXT2_MOUNT_DAX)
321 seq_puts(seq, ",dax");
322 #endif
323
324 if (!test_opt(sb, RESERVATION))
325 seq_puts(seq, ",noreservation");
326
327 spin_unlock(&sbi->s_lock);
328 return 0;
329 }
330
331 #ifdef CONFIG_QUOTA
332 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
333 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
334 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
335 const struct path *path);
ext2_get_dquots(struct inode * inode)336 static struct dquot **ext2_get_dquots(struct inode *inode)
337 {
338 return EXT2_I(inode)->i_dquot;
339 }
340
341 static const struct quotactl_ops ext2_quotactl_ops = {
342 .quota_on = ext2_quota_on,
343 .quota_off = ext2_quota_off,
344 .quota_sync = dquot_quota_sync,
345 .get_state = dquot_get_state,
346 .set_info = dquot_set_dqinfo,
347 .get_dqblk = dquot_get_dqblk,
348 .set_dqblk = dquot_set_dqblk,
349 .get_nextdqblk = dquot_get_next_dqblk,
350 };
351 #endif
352
353 static const struct super_operations ext2_sops = {
354 .alloc_inode = ext2_alloc_inode,
355 .destroy_inode = ext2_destroy_inode,
356 .write_inode = ext2_write_inode,
357 .evict_inode = ext2_evict_inode,
358 .put_super = ext2_put_super,
359 .sync_fs = ext2_sync_fs,
360 .freeze_fs = ext2_freeze,
361 .unfreeze_fs = ext2_unfreeze,
362 .statfs = ext2_statfs,
363 .remount_fs = ext2_remount,
364 .show_options = ext2_show_options,
365 #ifdef CONFIG_QUOTA
366 .quota_read = ext2_quota_read,
367 .quota_write = ext2_quota_write,
368 .get_dquots = ext2_get_dquots,
369 #endif
370 };
371
ext2_nfs_get_inode(struct super_block * sb,u64 ino,u32 generation)372 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
373 u64 ino, u32 generation)
374 {
375 struct inode *inode;
376
377 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
378 return ERR_PTR(-ESTALE);
379 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
380 return ERR_PTR(-ESTALE);
381
382 /*
383 * ext2_iget isn't quite right if the inode is currently unallocated!
384 * However ext2_iget currently does appropriate checks to handle stale
385 * inodes so everything is OK.
386 */
387 inode = ext2_iget(sb, ino);
388 if (IS_ERR(inode))
389 return ERR_CAST(inode);
390 if (generation && inode->i_generation != generation) {
391 /* we didn't find the right inode.. */
392 iput(inode);
393 return ERR_PTR(-ESTALE);
394 }
395 return inode;
396 }
397
ext2_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)398 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
399 int fh_len, int fh_type)
400 {
401 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
402 ext2_nfs_get_inode);
403 }
404
ext2_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)405 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
406 int fh_len, int fh_type)
407 {
408 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
409 ext2_nfs_get_inode);
410 }
411
412 static const struct export_operations ext2_export_ops = {
413 .fh_to_dentry = ext2_fh_to_dentry,
414 .fh_to_parent = ext2_fh_to_parent,
415 .get_parent = ext2_get_parent,
416 };
417
get_sb_block(void ** data)418 static unsigned long get_sb_block(void **data)
419 {
420 unsigned long sb_block;
421 char *options = (char *) *data;
422
423 if (!options || strncmp(options, "sb=", 3) != 0)
424 return 1; /* Default location */
425 options += 3;
426 sb_block = simple_strtoul(options, &options, 0);
427 if (*options && *options != ',') {
428 printk("EXT2-fs: Invalid sb specification: %s\n",
429 (char *) *data);
430 return 1;
431 }
432 if (*options == ',')
433 options++;
434 *data = (void *) options;
435 return sb_block;
436 }
437
438 enum {
439 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
440 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
441 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
442 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
443 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
444 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
445 };
446
447 static const match_table_t tokens = {
448 {Opt_bsd_df, "bsddf"},
449 {Opt_minix_df, "minixdf"},
450 {Opt_grpid, "grpid"},
451 {Opt_grpid, "bsdgroups"},
452 {Opt_nogrpid, "nogrpid"},
453 {Opt_nogrpid, "sysvgroups"},
454 {Opt_resgid, "resgid=%u"},
455 {Opt_resuid, "resuid=%u"},
456 {Opt_sb, "sb=%u"},
457 {Opt_err_cont, "errors=continue"},
458 {Opt_err_panic, "errors=panic"},
459 {Opt_err_ro, "errors=remount-ro"},
460 {Opt_nouid32, "nouid32"},
461 {Opt_nocheck, "check=none"},
462 {Opt_nocheck, "nocheck"},
463 {Opt_debug, "debug"},
464 {Opt_oldalloc, "oldalloc"},
465 {Opt_orlov, "orlov"},
466 {Opt_nobh, "nobh"},
467 {Opt_user_xattr, "user_xattr"},
468 {Opt_nouser_xattr, "nouser_xattr"},
469 {Opt_acl, "acl"},
470 {Opt_noacl, "noacl"},
471 {Opt_xip, "xip"},
472 {Opt_dax, "dax"},
473 {Opt_grpquota, "grpquota"},
474 {Opt_ignore, "noquota"},
475 {Opt_quota, "quota"},
476 {Opt_usrquota, "usrquota"},
477 {Opt_reservation, "reservation"},
478 {Opt_noreservation, "noreservation"},
479 {Opt_err, NULL}
480 };
481
parse_options(char * options,struct super_block * sb)482 static int parse_options(char *options, struct super_block *sb)
483 {
484 char *p;
485 struct ext2_sb_info *sbi = EXT2_SB(sb);
486 substring_t args[MAX_OPT_ARGS];
487 int option;
488 kuid_t uid;
489 kgid_t gid;
490
491 if (!options)
492 return 1;
493
494 while ((p = strsep (&options, ",")) != NULL) {
495 int token;
496 if (!*p)
497 continue;
498
499 token = match_token(p, tokens, args);
500 switch (token) {
501 case Opt_bsd_df:
502 clear_opt (sbi->s_mount_opt, MINIX_DF);
503 break;
504 case Opt_minix_df:
505 set_opt (sbi->s_mount_opt, MINIX_DF);
506 break;
507 case Opt_grpid:
508 set_opt (sbi->s_mount_opt, GRPID);
509 break;
510 case Opt_nogrpid:
511 clear_opt (sbi->s_mount_opt, GRPID);
512 break;
513 case Opt_resuid:
514 if (match_int(&args[0], &option))
515 return 0;
516 uid = make_kuid(current_user_ns(), option);
517 if (!uid_valid(uid)) {
518 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
519 return 0;
520
521 }
522 sbi->s_resuid = uid;
523 break;
524 case Opt_resgid:
525 if (match_int(&args[0], &option))
526 return 0;
527 gid = make_kgid(current_user_ns(), option);
528 if (!gid_valid(gid)) {
529 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
530 return 0;
531 }
532 sbi->s_resgid = gid;
533 break;
534 case Opt_sb:
535 /* handled by get_sb_block() instead of here */
536 /* *sb_block = match_int(&args[0]); */
537 break;
538 case Opt_err_panic:
539 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
540 clear_opt (sbi->s_mount_opt, ERRORS_RO);
541 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
542 break;
543 case Opt_err_ro:
544 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
545 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
546 set_opt (sbi->s_mount_opt, ERRORS_RO);
547 break;
548 case Opt_err_cont:
549 clear_opt (sbi->s_mount_opt, ERRORS_RO);
550 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
551 set_opt (sbi->s_mount_opt, ERRORS_CONT);
552 break;
553 case Opt_nouid32:
554 set_opt (sbi->s_mount_opt, NO_UID32);
555 break;
556 case Opt_nocheck:
557 clear_opt (sbi->s_mount_opt, CHECK);
558 break;
559 case Opt_debug:
560 set_opt (sbi->s_mount_opt, DEBUG);
561 break;
562 case Opt_oldalloc:
563 set_opt (sbi->s_mount_opt, OLDALLOC);
564 break;
565 case Opt_orlov:
566 clear_opt (sbi->s_mount_opt, OLDALLOC);
567 break;
568 case Opt_nobh:
569 set_opt (sbi->s_mount_opt, NOBH);
570 break;
571 #ifdef CONFIG_EXT2_FS_XATTR
572 case Opt_user_xattr:
573 set_opt (sbi->s_mount_opt, XATTR_USER);
574 break;
575 case Opt_nouser_xattr:
576 clear_opt (sbi->s_mount_opt, XATTR_USER);
577 break;
578 #else
579 case Opt_user_xattr:
580 case Opt_nouser_xattr:
581 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
582 "not supported");
583 break;
584 #endif
585 #ifdef CONFIG_EXT2_FS_POSIX_ACL
586 case Opt_acl:
587 set_opt(sbi->s_mount_opt, POSIX_ACL);
588 break;
589 case Opt_noacl:
590 clear_opt(sbi->s_mount_opt, POSIX_ACL);
591 break;
592 #else
593 case Opt_acl:
594 case Opt_noacl:
595 ext2_msg(sb, KERN_INFO,
596 "(no)acl options not supported");
597 break;
598 #endif
599 case Opt_xip:
600 ext2_msg(sb, KERN_INFO, "use dax instead of xip");
601 set_opt(sbi->s_mount_opt, XIP);
602 /* Fall through */
603 case Opt_dax:
604 #ifdef CONFIG_FS_DAX
605 ext2_msg(sb, KERN_WARNING,
606 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
607 set_opt(sbi->s_mount_opt, DAX);
608 #else
609 ext2_msg(sb, KERN_INFO, "dax option not supported");
610 #endif
611 break;
612
613 #if defined(CONFIG_QUOTA)
614 case Opt_quota:
615 case Opt_usrquota:
616 set_opt(sbi->s_mount_opt, USRQUOTA);
617 break;
618
619 case Opt_grpquota:
620 set_opt(sbi->s_mount_opt, GRPQUOTA);
621 break;
622 #else
623 case Opt_quota:
624 case Opt_usrquota:
625 case Opt_grpquota:
626 ext2_msg(sb, KERN_INFO,
627 "quota operations not supported");
628 break;
629 #endif
630
631 case Opt_reservation:
632 set_opt(sbi->s_mount_opt, RESERVATION);
633 ext2_msg(sb, KERN_INFO, "reservations ON");
634 break;
635 case Opt_noreservation:
636 clear_opt(sbi->s_mount_opt, RESERVATION);
637 ext2_msg(sb, KERN_INFO, "reservations OFF");
638 break;
639 case Opt_ignore:
640 break;
641 default:
642 return 0;
643 }
644 }
645 return 1;
646 }
647
ext2_setup_super(struct super_block * sb,struct ext2_super_block * es,int read_only)648 static int ext2_setup_super (struct super_block * sb,
649 struct ext2_super_block * es,
650 int read_only)
651 {
652 int res = 0;
653 struct ext2_sb_info *sbi = EXT2_SB(sb);
654
655 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
656 ext2_msg(sb, KERN_ERR,
657 "error: revision level too high, "
658 "forcing read-only mode");
659 res = MS_RDONLY;
660 }
661 if (read_only)
662 return res;
663 if (!(sbi->s_mount_state & EXT2_VALID_FS))
664 ext2_msg(sb, KERN_WARNING,
665 "warning: mounting unchecked fs, "
666 "running e2fsck is recommended");
667 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
668 ext2_msg(sb, KERN_WARNING,
669 "warning: mounting fs with errors, "
670 "running e2fsck is recommended");
671 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
672 le16_to_cpu(es->s_mnt_count) >=
673 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
674 ext2_msg(sb, KERN_WARNING,
675 "warning: maximal mount count reached, "
676 "running e2fsck is recommended");
677 else if (le32_to_cpu(es->s_checkinterval) &&
678 (le32_to_cpu(es->s_lastcheck) +
679 le32_to_cpu(es->s_checkinterval) <= get_seconds()))
680 ext2_msg(sb, KERN_WARNING,
681 "warning: checktime reached, "
682 "running e2fsck is recommended");
683 if (!le16_to_cpu(es->s_max_mnt_count))
684 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
685 le16_add_cpu(&es->s_mnt_count, 1);
686 if (test_opt (sb, DEBUG))
687 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
688 "bpg=%lu, ipg=%lu, mo=%04lx]",
689 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
690 sbi->s_frag_size,
691 sbi->s_groups_count,
692 EXT2_BLOCKS_PER_GROUP(sb),
693 EXT2_INODES_PER_GROUP(sb),
694 sbi->s_mount_opt);
695 return res;
696 }
697
ext2_check_descriptors(struct super_block * sb)698 static int ext2_check_descriptors(struct super_block *sb)
699 {
700 int i;
701 struct ext2_sb_info *sbi = EXT2_SB(sb);
702
703 ext2_debug ("Checking group descriptors");
704
705 for (i = 0; i < sbi->s_groups_count; i++) {
706 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
707 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
708 ext2_fsblk_t last_block;
709
710 if (i == sbi->s_groups_count - 1)
711 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
712 else
713 last_block = first_block +
714 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
715
716 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
717 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
718 {
719 ext2_error (sb, "ext2_check_descriptors",
720 "Block bitmap for group %d"
721 " not in group (block %lu)!",
722 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
723 return 0;
724 }
725 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
726 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
727 {
728 ext2_error (sb, "ext2_check_descriptors",
729 "Inode bitmap for group %d"
730 " not in group (block %lu)!",
731 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
732 return 0;
733 }
734 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
735 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
736 last_block)
737 {
738 ext2_error (sb, "ext2_check_descriptors",
739 "Inode table for group %d"
740 " not in group (block %lu)!",
741 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
742 return 0;
743 }
744 }
745 return 1;
746 }
747
748 /*
749 * Maximal file size. There is a direct, and {,double-,triple-}indirect
750 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
751 * We need to be 1 filesystem block less than the 2^32 sector limit.
752 */
ext2_max_size(int bits)753 static loff_t ext2_max_size(int bits)
754 {
755 loff_t res = EXT2_NDIR_BLOCKS;
756 int meta_blocks;
757 unsigned int upper_limit;
758 unsigned int ppb = 1 << (bits-2);
759
760 /* This is calculated to be the largest file size for a
761 * dense, file such that the total number of
762 * sectors in the file, including data and all indirect blocks,
763 * does not exceed 2^32 -1
764 * __u32 i_blocks representing the total number of
765 * 512 bytes blocks of the file
766 */
767 upper_limit = (1LL << 32) - 1;
768
769 /* total blocks in file system block size */
770 upper_limit >>= (bits - 9);
771
772 /* Compute how many blocks we can address by block tree */
773 res += 1LL << (bits-2);
774 res += 1LL << (2*(bits-2));
775 res += 1LL << (3*(bits-2));
776 /* Does block tree limit file size? */
777 if (res < upper_limit)
778 goto check_lfs;
779
780 res = upper_limit;
781 /* How many metadata blocks are needed for addressing upper_limit? */
782 upper_limit -= EXT2_NDIR_BLOCKS;
783 /* indirect blocks */
784 meta_blocks = 1;
785 upper_limit -= ppb;
786 /* double indirect blocks */
787 if (upper_limit < ppb * ppb) {
788 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
789 res -= meta_blocks;
790 goto check_lfs;
791 }
792 meta_blocks += 1 + ppb;
793 upper_limit -= ppb * ppb;
794 /* tripple indirect blocks for the rest */
795 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
796 DIV_ROUND_UP(upper_limit, ppb*ppb);
797 res -= meta_blocks;
798 check_lfs:
799 res <<= bits;
800 if (res > MAX_LFS_FILESIZE)
801 res = MAX_LFS_FILESIZE;
802
803 return res;
804 }
805
descriptor_loc(struct super_block * sb,unsigned long logic_sb_block,int nr)806 static unsigned long descriptor_loc(struct super_block *sb,
807 unsigned long logic_sb_block,
808 int nr)
809 {
810 struct ext2_sb_info *sbi = EXT2_SB(sb);
811 unsigned long bg, first_meta_bg;
812 int has_super = 0;
813
814 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
815
816 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
817 nr < first_meta_bg)
818 return (logic_sb_block + nr + 1);
819 bg = sbi->s_desc_per_block * nr;
820 if (ext2_bg_has_super(sb, bg))
821 has_super = 1;
822
823 return ext2_group_first_block_no(sb, bg) + has_super;
824 }
825
ext2_fill_super(struct super_block * sb,void * data,int silent)826 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
827 {
828 struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
829 struct buffer_head * bh;
830 struct ext2_sb_info * sbi;
831 struct ext2_super_block * es;
832 struct inode *root;
833 unsigned long block;
834 unsigned long sb_block = get_sb_block(&data);
835 unsigned long logic_sb_block;
836 unsigned long offset = 0;
837 unsigned long def_mount_opts;
838 long ret = -EINVAL;
839 int blocksize = BLOCK_SIZE;
840 int db_count;
841 int i, j;
842 __le32 features;
843 int err;
844
845 err = -ENOMEM;
846 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
847 if (!sbi)
848 goto failed;
849
850 sbi->s_blockgroup_lock =
851 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
852 if (!sbi->s_blockgroup_lock) {
853 kfree(sbi);
854 goto failed;
855 }
856 sb->s_fs_info = sbi;
857 sbi->s_sb_block = sb_block;
858 sbi->s_daxdev = dax_dev;
859
860 spin_lock_init(&sbi->s_lock);
861
862 /*
863 * See what the current blocksize for the device is, and
864 * use that as the blocksize. Otherwise (or if the blocksize
865 * is smaller than the default) use the default.
866 * This is important for devices that have a hardware
867 * sectorsize that is larger than the default.
868 */
869 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
870 if (!blocksize) {
871 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
872 goto failed_sbi;
873 }
874
875 /*
876 * If the superblock doesn't start on a hardware sector boundary,
877 * calculate the offset.
878 */
879 if (blocksize != BLOCK_SIZE) {
880 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
881 offset = (sb_block*BLOCK_SIZE) % blocksize;
882 } else {
883 logic_sb_block = sb_block;
884 }
885
886 if (!(bh = sb_bread(sb, logic_sb_block))) {
887 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
888 goto failed_sbi;
889 }
890 /*
891 * Note: s_es must be initialized as soon as possible because
892 * some ext2 macro-instructions depend on its value
893 */
894 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
895 sbi->s_es = es;
896 sb->s_magic = le16_to_cpu(es->s_magic);
897
898 if (sb->s_magic != EXT2_SUPER_MAGIC)
899 goto cantfind_ext2;
900
901 /* Set defaults before we parse the mount options */
902 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
903 if (def_mount_opts & EXT2_DEFM_DEBUG)
904 set_opt(sbi->s_mount_opt, DEBUG);
905 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
906 set_opt(sbi->s_mount_opt, GRPID);
907 if (def_mount_opts & EXT2_DEFM_UID16)
908 set_opt(sbi->s_mount_opt, NO_UID32);
909 #ifdef CONFIG_EXT2_FS_XATTR
910 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
911 set_opt(sbi->s_mount_opt, XATTR_USER);
912 #endif
913 #ifdef CONFIG_EXT2_FS_POSIX_ACL
914 if (def_mount_opts & EXT2_DEFM_ACL)
915 set_opt(sbi->s_mount_opt, POSIX_ACL);
916 #endif
917
918 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
919 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
920 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
921 set_opt(sbi->s_mount_opt, ERRORS_CONT);
922 else
923 set_opt(sbi->s_mount_opt, ERRORS_RO);
924
925 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
926 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
927
928 set_opt(sbi->s_mount_opt, RESERVATION);
929
930 if (!parse_options((char *) data, sb))
931 goto failed_mount;
932
933 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
934 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
935 MS_POSIXACL : 0);
936 sb->s_iflags |= SB_I_CGROUPWB;
937
938 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
939 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
940 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
941 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
942 ext2_msg(sb, KERN_WARNING,
943 "warning: feature flags set on rev 0 fs, "
944 "running e2fsck is recommended");
945 /*
946 * Check feature flags regardless of the revision level, since we
947 * previously didn't change the revision level when setting the flags,
948 * so there is a chance incompat flags are set on a rev 0 filesystem.
949 */
950 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
951 if (features) {
952 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
953 "unsupported optional features (%x)",
954 le32_to_cpu(features));
955 goto failed_mount;
956 }
957 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
958 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
959 "unsupported optional features (%x)",
960 le32_to_cpu(features));
961 goto failed_mount;
962 }
963
964 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
965
966 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
967 if (!bdev_dax_supported(sb->s_bdev, blocksize))
968 goto failed_mount;
969 }
970
971 /* If the blocksize doesn't match, re-read the thing.. */
972 if (sb->s_blocksize != blocksize) {
973 brelse(bh);
974
975 if (!sb_set_blocksize(sb, blocksize)) {
976 ext2_msg(sb, KERN_ERR,
977 "error: bad blocksize %d", blocksize);
978 goto failed_sbi;
979 }
980
981 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
982 offset = (sb_block*BLOCK_SIZE) % blocksize;
983 bh = sb_bread(sb, logic_sb_block);
984 if(!bh) {
985 ext2_msg(sb, KERN_ERR, "error: couldn't read"
986 "superblock on 2nd try");
987 goto failed_sbi;
988 }
989 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
990 sbi->s_es = es;
991 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
992 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
993 goto failed_mount;
994 }
995 }
996
997 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
998 sb->s_max_links = EXT2_LINK_MAX;
999
1000 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
1001 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
1002 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
1003 } else {
1004 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1005 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1006 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1007 !is_power_of_2(sbi->s_inode_size) ||
1008 (sbi->s_inode_size > blocksize)) {
1009 ext2_msg(sb, KERN_ERR,
1010 "error: unsupported inode size: %d",
1011 sbi->s_inode_size);
1012 goto failed_mount;
1013 }
1014 }
1015
1016 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
1017 le32_to_cpu(es->s_log_frag_size);
1018 if (sbi->s_frag_size == 0)
1019 goto cantfind_ext2;
1020 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
1021
1022 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1023 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1024 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1025
1026 if (EXT2_INODE_SIZE(sb) == 0)
1027 goto cantfind_ext2;
1028 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1029 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1030 goto cantfind_ext2;
1031 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1032 sbi->s_inodes_per_block;
1033 sbi->s_desc_per_block = sb->s_blocksize /
1034 sizeof (struct ext2_group_desc);
1035 sbi->s_sbh = bh;
1036 sbi->s_mount_state = le16_to_cpu(es->s_state);
1037 sbi->s_addr_per_block_bits =
1038 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1039 sbi->s_desc_per_block_bits =
1040 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1041
1042 if (sb->s_magic != EXT2_SUPER_MAGIC)
1043 goto cantfind_ext2;
1044
1045 if (sb->s_blocksize != bh->b_size) {
1046 if (!silent)
1047 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1048 goto failed_mount;
1049 }
1050
1051 if (sb->s_blocksize != sbi->s_frag_size) {
1052 ext2_msg(sb, KERN_ERR,
1053 "error: fragsize %lu != blocksize %lu"
1054 "(not supported yet)",
1055 sbi->s_frag_size, sb->s_blocksize);
1056 goto failed_mount;
1057 }
1058
1059 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1060 ext2_msg(sb, KERN_ERR,
1061 "error: #blocks per group too big: %lu",
1062 sbi->s_blocks_per_group);
1063 goto failed_mount;
1064 }
1065 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
1066 ext2_msg(sb, KERN_ERR,
1067 "error: #fragments per group too big: %lu",
1068 sbi->s_frags_per_group);
1069 goto failed_mount;
1070 }
1071 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1072 ext2_msg(sb, KERN_ERR,
1073 "error: #inodes per group too big: %lu",
1074 sbi->s_inodes_per_group);
1075 goto failed_mount;
1076 }
1077
1078 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1079 goto cantfind_ext2;
1080 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1081 le32_to_cpu(es->s_first_data_block) - 1)
1082 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1083 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1084 EXT2_DESC_PER_BLOCK(sb);
1085 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
1086 if (sbi->s_group_desc == NULL) {
1087 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1088 goto failed_mount;
1089 }
1090 bgl_lock_init(sbi->s_blockgroup_lock);
1091 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1092 if (!sbi->s_debts) {
1093 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1094 goto failed_mount_group_desc;
1095 }
1096 for (i = 0; i < db_count; i++) {
1097 block = descriptor_loc(sb, logic_sb_block, i);
1098 sbi->s_group_desc[i] = sb_bread(sb, block);
1099 if (!sbi->s_group_desc[i]) {
1100 for (j = 0; j < i; j++)
1101 brelse (sbi->s_group_desc[j]);
1102 ext2_msg(sb, KERN_ERR,
1103 "error: unable to read group descriptors");
1104 goto failed_mount_group_desc;
1105 }
1106 }
1107 if (!ext2_check_descriptors (sb)) {
1108 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1109 goto failed_mount2;
1110 }
1111 sbi->s_gdb_count = db_count;
1112 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1113 spin_lock_init(&sbi->s_next_gen_lock);
1114
1115 /* per fileystem reservation list head & lock */
1116 spin_lock_init(&sbi->s_rsv_window_lock);
1117 sbi->s_rsv_window_root = RB_ROOT;
1118 /*
1119 * Add a single, static dummy reservation to the start of the
1120 * reservation window list --- it gives us a placeholder for
1121 * append-at-start-of-list which makes the allocation logic
1122 * _much_ simpler.
1123 */
1124 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1125 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1126 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1127 sbi->s_rsv_window_head.rsv_goal_size = 0;
1128 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1129
1130 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1131 ext2_count_free_blocks(sb), GFP_KERNEL);
1132 if (!err) {
1133 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1134 ext2_count_free_inodes(sb), GFP_KERNEL);
1135 }
1136 if (!err) {
1137 err = percpu_counter_init(&sbi->s_dirs_counter,
1138 ext2_count_dirs(sb), GFP_KERNEL);
1139 }
1140 if (err) {
1141 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1142 goto failed_mount3;
1143 }
1144
1145 #ifdef CONFIG_EXT2_FS_XATTR
1146 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1147 if (!sbi->s_ea_block_cache) {
1148 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1149 goto failed_mount3;
1150 }
1151 #endif
1152 /*
1153 * set up enough so that it can read an inode
1154 */
1155 sb->s_op = &ext2_sops;
1156 sb->s_export_op = &ext2_export_ops;
1157 sb->s_xattr = ext2_xattr_handlers;
1158
1159 #ifdef CONFIG_QUOTA
1160 sb->dq_op = &dquot_operations;
1161 sb->s_qcop = &ext2_quotactl_ops;
1162 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1163 #endif
1164
1165 root = ext2_iget(sb, EXT2_ROOT_INO);
1166 if (IS_ERR(root)) {
1167 ret = PTR_ERR(root);
1168 goto failed_mount3;
1169 }
1170 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1171 iput(root);
1172 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1173 goto failed_mount3;
1174 }
1175
1176 sb->s_root = d_make_root(root);
1177 if (!sb->s_root) {
1178 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1179 ret = -ENOMEM;
1180 goto failed_mount3;
1181 }
1182 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1183 ext2_msg(sb, KERN_WARNING,
1184 "warning: mounting ext3 filesystem as ext2");
1185 if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1186 sb->s_flags |= MS_RDONLY;
1187 ext2_write_super(sb);
1188 return 0;
1189
1190 cantfind_ext2:
1191 if (!silent)
1192 ext2_msg(sb, KERN_ERR,
1193 "error: can't find an ext2 filesystem on dev %s.",
1194 sb->s_id);
1195 goto failed_mount;
1196 failed_mount3:
1197 if (sbi->s_ea_block_cache)
1198 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1199 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1200 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1201 percpu_counter_destroy(&sbi->s_dirs_counter);
1202 failed_mount2:
1203 for (i = 0; i < db_count; i++)
1204 brelse(sbi->s_group_desc[i]);
1205 failed_mount_group_desc:
1206 kfree(sbi->s_group_desc);
1207 kfree(sbi->s_debts);
1208 failed_mount:
1209 brelse(bh);
1210 failed_sbi:
1211 sb->s_fs_info = NULL;
1212 kfree(sbi->s_blockgroup_lock);
1213 kfree(sbi);
1214 failed:
1215 fs_put_dax(dax_dev);
1216 return ret;
1217 }
1218
ext2_clear_super_error(struct super_block * sb)1219 static void ext2_clear_super_error(struct super_block *sb)
1220 {
1221 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1222
1223 if (buffer_write_io_error(sbh)) {
1224 /*
1225 * Oh, dear. A previous attempt to write the
1226 * superblock failed. This could happen because the
1227 * USB device was yanked out. Or it could happen to
1228 * be a transient write error and maybe the block will
1229 * be remapped. Nothing we can do but to retry the
1230 * write and hope for the best.
1231 */
1232 ext2_msg(sb, KERN_ERR,
1233 "previous I/O error to superblock detected\n");
1234 clear_buffer_write_io_error(sbh);
1235 set_buffer_uptodate(sbh);
1236 }
1237 }
1238
ext2_sync_super(struct super_block * sb,struct ext2_super_block * es,int wait)1239 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1240 int wait)
1241 {
1242 ext2_clear_super_error(sb);
1243 spin_lock(&EXT2_SB(sb)->s_lock);
1244 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1245 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1246 es->s_wtime = cpu_to_le32(get_seconds());
1247 /* unlock before we do IO */
1248 spin_unlock(&EXT2_SB(sb)->s_lock);
1249 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1250 if (wait)
1251 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1252 }
1253
1254 /*
1255 * In the second extended file system, it is not necessary to
1256 * write the super block since we use a mapping of the
1257 * disk super block in a buffer.
1258 *
1259 * However, this function is still used to set the fs valid
1260 * flags to 0. We need to set this flag to 0 since the fs
1261 * may have been checked while mounted and e2fsck may have
1262 * set s_state to EXT2_VALID_FS after some corrections.
1263 */
ext2_sync_fs(struct super_block * sb,int wait)1264 static int ext2_sync_fs(struct super_block *sb, int wait)
1265 {
1266 struct ext2_sb_info *sbi = EXT2_SB(sb);
1267 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1268
1269 /*
1270 * Write quota structures to quota file, sync_blockdev() will write
1271 * them to disk later
1272 */
1273 dquot_writeback_dquots(sb, -1);
1274
1275 spin_lock(&sbi->s_lock);
1276 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1277 ext2_debug("setting valid to 0\n");
1278 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1279 }
1280 spin_unlock(&sbi->s_lock);
1281 ext2_sync_super(sb, es, wait);
1282 return 0;
1283 }
1284
ext2_freeze(struct super_block * sb)1285 static int ext2_freeze(struct super_block *sb)
1286 {
1287 struct ext2_sb_info *sbi = EXT2_SB(sb);
1288
1289 /*
1290 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1291 * because we have unattached inodes and thus filesystem is not fully
1292 * consistent.
1293 */
1294 if (atomic_long_read(&sb->s_remove_count)) {
1295 ext2_sync_fs(sb, 1);
1296 return 0;
1297 }
1298 /* Set EXT2_FS_VALID flag */
1299 spin_lock(&sbi->s_lock);
1300 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1301 spin_unlock(&sbi->s_lock);
1302 ext2_sync_super(sb, sbi->s_es, 1);
1303
1304 return 0;
1305 }
1306
ext2_unfreeze(struct super_block * sb)1307 static int ext2_unfreeze(struct super_block *sb)
1308 {
1309 /* Just write sb to clear EXT2_VALID_FS flag */
1310 ext2_write_super(sb);
1311
1312 return 0;
1313 }
1314
ext2_write_super(struct super_block * sb)1315 static void ext2_write_super(struct super_block *sb)
1316 {
1317 if (!sb_rdonly(sb))
1318 ext2_sync_fs(sb, 1);
1319 }
1320
ext2_remount(struct super_block * sb,int * flags,char * data)1321 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1322 {
1323 struct ext2_sb_info * sbi = EXT2_SB(sb);
1324 struct ext2_super_block * es;
1325 struct ext2_mount_options old_opts;
1326 unsigned long old_sb_flags;
1327 int err;
1328
1329 sync_filesystem(sb);
1330 spin_lock(&sbi->s_lock);
1331
1332 /* Store the old options */
1333 old_sb_flags = sb->s_flags;
1334 old_opts.s_mount_opt = sbi->s_mount_opt;
1335 old_opts.s_resuid = sbi->s_resuid;
1336 old_opts.s_resgid = sbi->s_resgid;
1337
1338 /*
1339 * Allow the "check" option to be passed as a remount option.
1340 */
1341 if (!parse_options(data, sb)) {
1342 err = -EINVAL;
1343 goto restore_opts;
1344 }
1345
1346 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1347 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1348
1349 es = sbi->s_es;
1350 if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1351 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1352 "dax flag with busy inodes while remounting");
1353 sbi->s_mount_opt ^= EXT2_MOUNT_DAX;
1354 }
1355 if ((bool)(*flags & MS_RDONLY) == sb_rdonly(sb)) {
1356 spin_unlock(&sbi->s_lock);
1357 return 0;
1358 }
1359 if (*flags & MS_RDONLY) {
1360 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1361 !(sbi->s_mount_state & EXT2_VALID_FS)) {
1362 spin_unlock(&sbi->s_lock);
1363 return 0;
1364 }
1365
1366 /*
1367 * OK, we are remounting a valid rw partition rdonly, so set
1368 * the rdonly flag and then mark the partition as valid again.
1369 */
1370 es->s_state = cpu_to_le16(sbi->s_mount_state);
1371 es->s_mtime = cpu_to_le32(get_seconds());
1372 spin_unlock(&sbi->s_lock);
1373
1374 err = dquot_suspend(sb, -1);
1375 if (err < 0) {
1376 spin_lock(&sbi->s_lock);
1377 goto restore_opts;
1378 }
1379
1380 ext2_sync_super(sb, es, 1);
1381 } else {
1382 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1383 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1384 if (ret) {
1385 ext2_msg(sb, KERN_WARNING,
1386 "warning: couldn't remount RDWR because of "
1387 "unsupported optional features (%x).",
1388 le32_to_cpu(ret));
1389 err = -EROFS;
1390 goto restore_opts;
1391 }
1392 /*
1393 * Mounting a RDONLY partition read-write, so reread and
1394 * store the current valid flag. (It may have been changed
1395 * by e2fsck since we originally mounted the partition.)
1396 */
1397 sbi->s_mount_state = le16_to_cpu(es->s_state);
1398 if (!ext2_setup_super (sb, es, 0))
1399 sb->s_flags &= ~MS_RDONLY;
1400 spin_unlock(&sbi->s_lock);
1401
1402 ext2_write_super(sb);
1403
1404 dquot_resume(sb, -1);
1405 }
1406
1407 return 0;
1408 restore_opts:
1409 sbi->s_mount_opt = old_opts.s_mount_opt;
1410 sbi->s_resuid = old_opts.s_resuid;
1411 sbi->s_resgid = old_opts.s_resgid;
1412 sb->s_flags = old_sb_flags;
1413 spin_unlock(&sbi->s_lock);
1414 return err;
1415 }
1416
ext2_statfs(struct dentry * dentry,struct kstatfs * buf)1417 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1418 {
1419 struct super_block *sb = dentry->d_sb;
1420 struct ext2_sb_info *sbi = EXT2_SB(sb);
1421 struct ext2_super_block *es = sbi->s_es;
1422 u64 fsid;
1423
1424 spin_lock(&sbi->s_lock);
1425
1426 if (test_opt (sb, MINIX_DF))
1427 sbi->s_overhead_last = 0;
1428 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1429 unsigned long i, overhead = 0;
1430 smp_rmb();
1431
1432 /*
1433 * Compute the overhead (FS structures). This is constant
1434 * for a given filesystem unless the number of block groups
1435 * changes so we cache the previous value until it does.
1436 */
1437
1438 /*
1439 * All of the blocks before first_data_block are
1440 * overhead
1441 */
1442 overhead = le32_to_cpu(es->s_first_data_block);
1443
1444 /*
1445 * Add the overhead attributed to the superblock and
1446 * block group descriptors. If the sparse superblocks
1447 * feature is turned on, then not all groups have this.
1448 */
1449 for (i = 0; i < sbi->s_groups_count; i++)
1450 overhead += ext2_bg_has_super(sb, i) +
1451 ext2_bg_num_gdb(sb, i);
1452
1453 /*
1454 * Every block group has an inode bitmap, a block
1455 * bitmap, and an inode table.
1456 */
1457 overhead += (sbi->s_groups_count *
1458 (2 + sbi->s_itb_per_group));
1459 sbi->s_overhead_last = overhead;
1460 smp_wmb();
1461 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1462 }
1463
1464 buf->f_type = EXT2_SUPER_MAGIC;
1465 buf->f_bsize = sb->s_blocksize;
1466 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1467 buf->f_bfree = ext2_count_free_blocks(sb);
1468 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1469 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1470 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1471 buf->f_bavail = 0;
1472 buf->f_files = le32_to_cpu(es->s_inodes_count);
1473 buf->f_ffree = ext2_count_free_inodes(sb);
1474 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1475 buf->f_namelen = EXT2_NAME_LEN;
1476 fsid = le64_to_cpup((void *)es->s_uuid) ^
1477 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1478 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1479 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1480 spin_unlock(&sbi->s_lock);
1481 return 0;
1482 }
1483
ext2_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)1484 static struct dentry *ext2_mount(struct file_system_type *fs_type,
1485 int flags, const char *dev_name, void *data)
1486 {
1487 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1488 }
1489
1490 #ifdef CONFIG_QUOTA
1491
1492 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1493 * acquiring the locks... As quota files are never truncated and quota code
1494 * itself serializes the operations (and no one else should touch the files)
1495 * we don't have to be afraid of races */
ext2_quota_read(struct super_block * sb,int type,char * data,size_t len,loff_t off)1496 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1497 size_t len, loff_t off)
1498 {
1499 struct inode *inode = sb_dqopt(sb)->files[type];
1500 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1501 int err = 0;
1502 int offset = off & (sb->s_blocksize - 1);
1503 int tocopy;
1504 size_t toread;
1505 struct buffer_head tmp_bh;
1506 struct buffer_head *bh;
1507 loff_t i_size = i_size_read(inode);
1508
1509 if (off > i_size)
1510 return 0;
1511 if (off+len > i_size)
1512 len = i_size-off;
1513 toread = len;
1514 while (toread > 0) {
1515 tocopy = sb->s_blocksize - offset < toread ?
1516 sb->s_blocksize - offset : toread;
1517
1518 tmp_bh.b_state = 0;
1519 tmp_bh.b_size = sb->s_blocksize;
1520 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1521 if (err < 0)
1522 return err;
1523 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1524 memset(data, 0, tocopy);
1525 else {
1526 bh = sb_bread(sb, tmp_bh.b_blocknr);
1527 if (!bh)
1528 return -EIO;
1529 memcpy(data, bh->b_data+offset, tocopy);
1530 brelse(bh);
1531 }
1532 offset = 0;
1533 toread -= tocopy;
1534 data += tocopy;
1535 blk++;
1536 }
1537 return len;
1538 }
1539
1540 /* Write to quotafile */
ext2_quota_write(struct super_block * sb,int type,const char * data,size_t len,loff_t off)1541 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1542 const char *data, size_t len, loff_t off)
1543 {
1544 struct inode *inode = sb_dqopt(sb)->files[type];
1545 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1546 int err = 0;
1547 int offset = off & (sb->s_blocksize - 1);
1548 int tocopy;
1549 size_t towrite = len;
1550 struct buffer_head tmp_bh;
1551 struct buffer_head *bh;
1552
1553 while (towrite > 0) {
1554 tocopy = sb->s_blocksize - offset < towrite ?
1555 sb->s_blocksize - offset : towrite;
1556
1557 tmp_bh.b_state = 0;
1558 tmp_bh.b_size = sb->s_blocksize;
1559 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1560 if (err < 0)
1561 goto out;
1562 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1563 bh = sb_bread(sb, tmp_bh.b_blocknr);
1564 else
1565 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1566 if (unlikely(!bh)) {
1567 err = -EIO;
1568 goto out;
1569 }
1570 lock_buffer(bh);
1571 memcpy(bh->b_data+offset, data, tocopy);
1572 flush_dcache_page(bh->b_page);
1573 set_buffer_uptodate(bh);
1574 mark_buffer_dirty(bh);
1575 unlock_buffer(bh);
1576 brelse(bh);
1577 offset = 0;
1578 towrite -= tocopy;
1579 data += tocopy;
1580 blk++;
1581 }
1582 out:
1583 if (len == towrite)
1584 return err;
1585 if (inode->i_size < off+len-towrite)
1586 i_size_write(inode, off+len-towrite);
1587 inode->i_version++;
1588 inode->i_mtime = inode->i_ctime = current_time(inode);
1589 mark_inode_dirty(inode);
1590 return len - towrite;
1591 }
1592
ext2_quota_on(struct super_block * sb,int type,int format_id,const struct path * path)1593 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1594 const struct path *path)
1595 {
1596 int err;
1597 struct inode *inode;
1598
1599 err = dquot_quota_on(sb, type, format_id, path);
1600 if (err)
1601 return err;
1602
1603 inode = d_inode(path->dentry);
1604 inode_lock(inode);
1605 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1606 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1607 S_NOATIME | S_IMMUTABLE);
1608 inode_unlock(inode);
1609 mark_inode_dirty(inode);
1610
1611 return 0;
1612 }
1613
ext2_quota_off(struct super_block * sb,int type)1614 static int ext2_quota_off(struct super_block *sb, int type)
1615 {
1616 struct inode *inode = sb_dqopt(sb)->files[type];
1617 int err;
1618
1619 if (!inode || !igrab(inode))
1620 goto out;
1621
1622 err = dquot_quota_off(sb, type);
1623 if (err)
1624 goto out_put;
1625
1626 inode_lock(inode);
1627 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1628 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1629 inode_unlock(inode);
1630 mark_inode_dirty(inode);
1631 out_put:
1632 iput(inode);
1633 return err;
1634 out:
1635 return dquot_quota_off(sb, type);
1636 }
1637
1638 #endif
1639
1640 static struct file_system_type ext2_fs_type = {
1641 .owner = THIS_MODULE,
1642 .name = "ext2",
1643 .mount = ext2_mount,
1644 .kill_sb = kill_block_super,
1645 .fs_flags = FS_REQUIRES_DEV,
1646 };
1647 MODULE_ALIAS_FS("ext2");
1648
init_ext2_fs(void)1649 static int __init init_ext2_fs(void)
1650 {
1651 int err;
1652
1653 err = init_inodecache();
1654 if (err)
1655 return err;
1656 err = register_filesystem(&ext2_fs_type);
1657 if (err)
1658 goto out;
1659 return 0;
1660 out:
1661 destroy_inodecache();
1662 return err;
1663 }
1664
exit_ext2_fs(void)1665 static void __exit exit_ext2_fs(void)
1666 {
1667 unregister_filesystem(&ext2_fs_type);
1668 destroy_inodecache();
1669 }
1670
1671 MODULE_AUTHOR("Remy Card and others");
1672 MODULE_DESCRIPTION("Second Extended Filesystem");
1673 MODULE_LICENSE("GPL");
1674 module_init(init_ext2_fs)
1675 module_exit(exit_ext2_fs)
1676