1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/fs/ext2/super.c
4 *
5 * Copyright (C) 1992, 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Laboratoire MASI - Institut Blaise Pascal
8 * Universite Pierre et Marie Curie (Paris VI)
9 *
10 * from
11 *
12 * linux/fs/minix/inode.c
13 *
14 * Copyright (C) 1991, 1992 Linus Torvalds
15 *
16 * Big-endian to little-endian byte-swapping/bitmaps by
17 * David S. Miller (davem@caip.rutgers.edu), 1995
18 */
19
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/slab.h>
24 #include <linux/init.h>
25 #include <linux/blkdev.h>
26 #include <linux/parser.h>
27 #include <linux/random.h>
28 #include <linux/buffer_head.h>
29 #include <linux/exportfs.h>
30 #include <linux/vfs.h>
31 #include <linux/seq_file.h>
32 #include <linux/mount.h>
33 #include <linux/log2.h>
34 #include <linux/quotaops.h>
35 #include <linux/uaccess.h>
36 #include <linux/dax.h>
37 #include <linux/iversion.h>
38 #include "ext2.h"
39 #include "xattr.h"
40 #include "acl.h"
41
42 static void ext2_write_super(struct super_block *sb);
43 static int ext2_remount (struct super_block * sb, int * flags, char * data);
44 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
45 static int ext2_sync_fs(struct super_block *sb, int wait);
46 static int ext2_freeze(struct super_block *sb);
47 static int ext2_unfreeze(struct super_block *sb);
48
ext2_error(struct super_block * sb,const char * function,const char * fmt,...)49 void ext2_error(struct super_block *sb, const char *function,
50 const char *fmt, ...)
51 {
52 struct va_format vaf;
53 va_list args;
54 struct ext2_sb_info *sbi = EXT2_SB(sb);
55 struct ext2_super_block *es = sbi->s_es;
56
57 if (!sb_rdonly(sb)) {
58 spin_lock(&sbi->s_lock);
59 sbi->s_mount_state |= EXT2_ERROR_FS;
60 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
61 spin_unlock(&sbi->s_lock);
62 ext2_sync_super(sb, es, 1);
63 }
64
65 va_start(args, fmt);
66
67 vaf.fmt = fmt;
68 vaf.va = &args;
69
70 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
71 sb->s_id, function, &vaf);
72
73 va_end(args);
74
75 if (test_opt(sb, ERRORS_PANIC))
76 panic("EXT2-fs: panic from previous error\n");
77 if (!sb_rdonly(sb) && test_opt(sb, ERRORS_RO)) {
78 ext2_msg(sb, KERN_CRIT,
79 "error: remounting filesystem read-only");
80 sb->s_flags |= SB_RDONLY;
81 }
82 }
83
ext2_msg(struct super_block * sb,const char * prefix,const char * fmt,...)84 void ext2_msg(struct super_block *sb, const char *prefix,
85 const char *fmt, ...)
86 {
87 struct va_format vaf;
88 va_list args;
89
90 va_start(args, fmt);
91
92 vaf.fmt = fmt;
93 vaf.va = &args;
94
95 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
96
97 va_end(args);
98 }
99
100 /*
101 * This must be called with sbi->s_lock held.
102 */
ext2_update_dynamic_rev(struct super_block * sb)103 void ext2_update_dynamic_rev(struct super_block *sb)
104 {
105 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
106
107 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
108 return;
109
110 ext2_msg(sb, KERN_WARNING,
111 "warning: updating to rev %d because of "
112 "new feature flag, running e2fsck is recommended",
113 EXT2_DYNAMIC_REV);
114
115 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
116 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
117 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
118 /* leave es->s_feature_*compat flags alone */
119 /* es->s_uuid will be set by e2fsck if empty */
120
121 /*
122 * The rest of the superblock fields should be zero, and if not it
123 * means they are likely already in use, so leave them alone. We
124 * can leave it up to e2fsck to clean up any inconsistencies there.
125 */
126 }
127
128 #ifdef CONFIG_QUOTA
129 static int ext2_quota_off(struct super_block *sb, int type);
130
ext2_quota_off_umount(struct super_block * sb)131 static void ext2_quota_off_umount(struct super_block *sb)
132 {
133 int type;
134
135 for (type = 0; type < MAXQUOTAS; type++)
136 ext2_quota_off(sb, type);
137 }
138 #else
ext2_quota_off_umount(struct super_block * sb)139 static inline void ext2_quota_off_umount(struct super_block *sb)
140 {
141 }
142 #endif
143
ext2_put_super(struct super_block * sb)144 static void ext2_put_super (struct super_block * sb)
145 {
146 int db_count;
147 int i;
148 struct ext2_sb_info *sbi = EXT2_SB(sb);
149
150 ext2_quota_off_umount(sb);
151
152 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
153 sbi->s_ea_block_cache = NULL;
154
155 if (!sb_rdonly(sb)) {
156 struct ext2_super_block *es = sbi->s_es;
157
158 spin_lock(&sbi->s_lock);
159 es->s_state = cpu_to_le16(sbi->s_mount_state);
160 spin_unlock(&sbi->s_lock);
161 ext2_sync_super(sb, es, 1);
162 }
163 db_count = sbi->s_gdb_count;
164 for (i = 0; i < db_count; i++)
165 brelse(sbi->s_group_desc[i]);
166 kfree(sbi->s_group_desc);
167 kfree(sbi->s_debts);
168 percpu_counter_destroy(&sbi->s_freeblocks_counter);
169 percpu_counter_destroy(&sbi->s_freeinodes_counter);
170 percpu_counter_destroy(&sbi->s_dirs_counter);
171 brelse (sbi->s_sbh);
172 sb->s_fs_info = NULL;
173 kfree(sbi->s_blockgroup_lock);
174 fs_put_dax(sbi->s_daxdev);
175 kfree(sbi);
176 }
177
178 static struct kmem_cache * ext2_inode_cachep;
179
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 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
ext2_free_in_core_inode(struct inode * inode)195 static void ext2_free_in_core_inode(struct inode *inode)
196 {
197 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
198 }
199
init_once(void * foo)200 static void init_once(void *foo)
201 {
202 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
203
204 rwlock_init(&ei->i_meta_lock);
205 #ifdef CONFIG_EXT2_FS_XATTR
206 init_rwsem(&ei->xattr_sem);
207 #endif
208 mutex_init(&ei->truncate_mutex);
209 #ifdef CONFIG_FS_DAX
210 init_rwsem(&ei->dax_sem);
211 #endif
212 inode_init_once(&ei->vfs_inode);
213 }
214
init_inodecache(void)215 static int __init init_inodecache(void)
216 {
217 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",
218 sizeof(struct ext2_inode_info), 0,
219 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
220 SLAB_ACCOUNT),
221 offsetof(struct ext2_inode_info, i_data),
222 sizeof_field(struct ext2_inode_info, i_data),
223 init_once);
224 if (ext2_inode_cachep == NULL)
225 return -ENOMEM;
226 return 0;
227 }
228
destroy_inodecache(void)229 static void destroy_inodecache(void)
230 {
231 /*
232 * Make sure all delayed rcu free inodes are flushed before we
233 * destroy cache.
234 */
235 rcu_barrier();
236 kmem_cache_destroy(ext2_inode_cachep);
237 }
238
ext2_show_options(struct seq_file * seq,struct dentry * root)239 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
240 {
241 struct super_block *sb = root->d_sb;
242 struct ext2_sb_info *sbi = EXT2_SB(sb);
243 struct ext2_super_block *es = sbi->s_es;
244 unsigned long def_mount_opts;
245
246 spin_lock(&sbi->s_lock);
247 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
248
249 if (sbi->s_sb_block != 1)
250 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
251 if (test_opt(sb, MINIX_DF))
252 seq_puts(seq, ",minixdf");
253 if (test_opt(sb, GRPID))
254 seq_puts(seq, ",grpid");
255 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
256 seq_puts(seq, ",nogrpid");
257 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
258 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
259 seq_printf(seq, ",resuid=%u",
260 from_kuid_munged(&init_user_ns, sbi->s_resuid));
261 }
262 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
263 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
264 seq_printf(seq, ",resgid=%u",
265 from_kgid_munged(&init_user_ns, sbi->s_resgid));
266 }
267 if (test_opt(sb, ERRORS_RO)) {
268 int def_errors = le16_to_cpu(es->s_errors);
269
270 if (def_errors == EXT2_ERRORS_PANIC ||
271 def_errors == EXT2_ERRORS_CONTINUE) {
272 seq_puts(seq, ",errors=remount-ro");
273 }
274 }
275 if (test_opt(sb, ERRORS_CONT))
276 seq_puts(seq, ",errors=continue");
277 if (test_opt(sb, ERRORS_PANIC))
278 seq_puts(seq, ",errors=panic");
279 if (test_opt(sb, NO_UID32))
280 seq_puts(seq, ",nouid32");
281 if (test_opt(sb, DEBUG))
282 seq_puts(seq, ",debug");
283 if (test_opt(sb, OLDALLOC))
284 seq_puts(seq, ",oldalloc");
285
286 #ifdef CONFIG_EXT2_FS_XATTR
287 if (test_opt(sb, XATTR_USER))
288 seq_puts(seq, ",user_xattr");
289 if (!test_opt(sb, XATTR_USER) &&
290 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
291 seq_puts(seq, ",nouser_xattr");
292 }
293 #endif
294
295 #ifdef CONFIG_EXT2_FS_POSIX_ACL
296 if (test_opt(sb, POSIX_ACL))
297 seq_puts(seq, ",acl");
298 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
299 seq_puts(seq, ",noacl");
300 #endif
301
302 if (test_opt(sb, NOBH))
303 seq_puts(seq, ",nobh");
304
305 if (test_opt(sb, USRQUOTA))
306 seq_puts(seq, ",usrquota");
307
308 if (test_opt(sb, GRPQUOTA))
309 seq_puts(seq, ",grpquota");
310
311 if (test_opt(sb, XIP))
312 seq_puts(seq, ",xip");
313
314 if (test_opt(sb, DAX))
315 seq_puts(seq, ",dax");
316
317 if (!test_opt(sb, RESERVATION))
318 seq_puts(seq, ",noreservation");
319
320 spin_unlock(&sbi->s_lock);
321 return 0;
322 }
323
324 #ifdef CONFIG_QUOTA
325 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
326 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
327 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
328 const struct path *path);
ext2_get_dquots(struct inode * inode)329 static struct dquot **ext2_get_dquots(struct inode *inode)
330 {
331 return EXT2_I(inode)->i_dquot;
332 }
333
334 static const struct quotactl_ops ext2_quotactl_ops = {
335 .quota_on = ext2_quota_on,
336 .quota_off = ext2_quota_off,
337 .quota_sync = dquot_quota_sync,
338 .get_state = dquot_get_state,
339 .set_info = dquot_set_dqinfo,
340 .get_dqblk = dquot_get_dqblk,
341 .set_dqblk = dquot_set_dqblk,
342 .get_nextdqblk = dquot_get_next_dqblk,
343 };
344 #endif
345
346 static const struct super_operations ext2_sops = {
347 .alloc_inode = ext2_alloc_inode,
348 .free_inode = ext2_free_in_core_inode,
349 .write_inode = ext2_write_inode,
350 .evict_inode = ext2_evict_inode,
351 .put_super = ext2_put_super,
352 .sync_fs = ext2_sync_fs,
353 .freeze_fs = ext2_freeze,
354 .unfreeze_fs = ext2_unfreeze,
355 .statfs = ext2_statfs,
356 .remount_fs = ext2_remount,
357 .show_options = ext2_show_options,
358 #ifdef CONFIG_QUOTA
359 .quota_read = ext2_quota_read,
360 .quota_write = ext2_quota_write,
361 .get_dquots = ext2_get_dquots,
362 #endif
363 };
364
ext2_nfs_get_inode(struct super_block * sb,u64 ino,u32 generation)365 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
366 u64 ino, u32 generation)
367 {
368 struct inode *inode;
369
370 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
371 return ERR_PTR(-ESTALE);
372 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
373 return ERR_PTR(-ESTALE);
374
375 /*
376 * ext2_iget isn't quite right if the inode is currently unallocated!
377 * However ext2_iget currently does appropriate checks to handle stale
378 * inodes so everything is OK.
379 */
380 inode = ext2_iget(sb, ino);
381 if (IS_ERR(inode))
382 return ERR_CAST(inode);
383 if (generation && inode->i_generation != generation) {
384 /* we didn't find the right inode.. */
385 iput(inode);
386 return ERR_PTR(-ESTALE);
387 }
388 return inode;
389 }
390
ext2_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)391 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
392 int fh_len, int fh_type)
393 {
394 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
395 ext2_nfs_get_inode);
396 }
397
ext2_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)398 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
399 int fh_len, int fh_type)
400 {
401 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
402 ext2_nfs_get_inode);
403 }
404
405 static const struct export_operations ext2_export_ops = {
406 .fh_to_dentry = ext2_fh_to_dentry,
407 .fh_to_parent = ext2_fh_to_parent,
408 .get_parent = ext2_get_parent,
409 };
410
get_sb_block(void ** data)411 static unsigned long get_sb_block(void **data)
412 {
413 unsigned long sb_block;
414 char *options = (char *) *data;
415
416 if (!options || strncmp(options, "sb=", 3) != 0)
417 return 1; /* Default location */
418 options += 3;
419 sb_block = simple_strtoul(options, &options, 0);
420 if (*options && *options != ',') {
421 printk("EXT2-fs: Invalid sb specification: %s\n",
422 (char *) *data);
423 return 1;
424 }
425 if (*options == ',')
426 options++;
427 *data = (void *) options;
428 return sb_block;
429 }
430
431 enum {
432 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
433 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
434 Opt_err_ro, Opt_nouid32, Opt_debug,
435 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
436 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
437 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
438 };
439
440 static const match_table_t tokens = {
441 {Opt_bsd_df, "bsddf"},
442 {Opt_minix_df, "minixdf"},
443 {Opt_grpid, "grpid"},
444 {Opt_grpid, "bsdgroups"},
445 {Opt_nogrpid, "nogrpid"},
446 {Opt_nogrpid, "sysvgroups"},
447 {Opt_resgid, "resgid=%u"},
448 {Opt_resuid, "resuid=%u"},
449 {Opt_sb, "sb=%u"},
450 {Opt_err_cont, "errors=continue"},
451 {Opt_err_panic, "errors=panic"},
452 {Opt_err_ro, "errors=remount-ro"},
453 {Opt_nouid32, "nouid32"},
454 {Opt_debug, "debug"},
455 {Opt_oldalloc, "oldalloc"},
456 {Opt_orlov, "orlov"},
457 {Opt_nobh, "nobh"},
458 {Opt_user_xattr, "user_xattr"},
459 {Opt_nouser_xattr, "nouser_xattr"},
460 {Opt_acl, "acl"},
461 {Opt_noacl, "noacl"},
462 {Opt_xip, "xip"},
463 {Opt_dax, "dax"},
464 {Opt_grpquota, "grpquota"},
465 {Opt_ignore, "noquota"},
466 {Opt_quota, "quota"},
467 {Opt_usrquota, "usrquota"},
468 {Opt_reservation, "reservation"},
469 {Opt_noreservation, "noreservation"},
470 {Opt_err, NULL}
471 };
472
parse_options(char * options,struct super_block * sb,struct ext2_mount_options * opts)473 static int parse_options(char *options, struct super_block *sb,
474 struct ext2_mount_options *opts)
475 {
476 char *p;
477 substring_t args[MAX_OPT_ARGS];
478 int option;
479 kuid_t uid;
480 kgid_t gid;
481
482 if (!options)
483 return 1;
484
485 while ((p = strsep (&options, ",")) != NULL) {
486 int token;
487 if (!*p)
488 continue;
489
490 token = match_token(p, tokens, args);
491 switch (token) {
492 case Opt_bsd_df:
493 clear_opt (opts->s_mount_opt, MINIX_DF);
494 break;
495 case Opt_minix_df:
496 set_opt (opts->s_mount_opt, MINIX_DF);
497 break;
498 case Opt_grpid:
499 set_opt (opts->s_mount_opt, GRPID);
500 break;
501 case Opt_nogrpid:
502 clear_opt (opts->s_mount_opt, GRPID);
503 break;
504 case Opt_resuid:
505 if (match_int(&args[0], &option))
506 return 0;
507 uid = make_kuid(current_user_ns(), option);
508 if (!uid_valid(uid)) {
509 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
510 return 0;
511
512 }
513 opts->s_resuid = uid;
514 break;
515 case Opt_resgid:
516 if (match_int(&args[0], &option))
517 return 0;
518 gid = make_kgid(current_user_ns(), option);
519 if (!gid_valid(gid)) {
520 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
521 return 0;
522 }
523 opts->s_resgid = gid;
524 break;
525 case Opt_sb:
526 /* handled by get_sb_block() instead of here */
527 /* *sb_block = match_int(&args[0]); */
528 break;
529 case Opt_err_panic:
530 clear_opt (opts->s_mount_opt, ERRORS_CONT);
531 clear_opt (opts->s_mount_opt, ERRORS_RO);
532 set_opt (opts->s_mount_opt, ERRORS_PANIC);
533 break;
534 case Opt_err_ro:
535 clear_opt (opts->s_mount_opt, ERRORS_CONT);
536 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
537 set_opt (opts->s_mount_opt, ERRORS_RO);
538 break;
539 case Opt_err_cont:
540 clear_opt (opts->s_mount_opt, ERRORS_RO);
541 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
542 set_opt (opts->s_mount_opt, ERRORS_CONT);
543 break;
544 case Opt_nouid32:
545 set_opt (opts->s_mount_opt, NO_UID32);
546 break;
547 case Opt_debug:
548 set_opt (opts->s_mount_opt, DEBUG);
549 break;
550 case Opt_oldalloc:
551 set_opt (opts->s_mount_opt, OLDALLOC);
552 break;
553 case Opt_orlov:
554 clear_opt (opts->s_mount_opt, OLDALLOC);
555 break;
556 case Opt_nobh:
557 set_opt (opts->s_mount_opt, NOBH);
558 break;
559 #ifdef CONFIG_EXT2_FS_XATTR
560 case Opt_user_xattr:
561 set_opt (opts->s_mount_opt, XATTR_USER);
562 break;
563 case Opt_nouser_xattr:
564 clear_opt (opts->s_mount_opt, XATTR_USER);
565 break;
566 #else
567 case Opt_user_xattr:
568 case Opt_nouser_xattr:
569 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
570 "not supported");
571 break;
572 #endif
573 #ifdef CONFIG_EXT2_FS_POSIX_ACL
574 case Opt_acl:
575 set_opt(opts->s_mount_opt, POSIX_ACL);
576 break;
577 case Opt_noacl:
578 clear_opt(opts->s_mount_opt, POSIX_ACL);
579 break;
580 #else
581 case Opt_acl:
582 case Opt_noacl:
583 ext2_msg(sb, KERN_INFO,
584 "(no)acl options not supported");
585 break;
586 #endif
587 case Opt_xip:
588 ext2_msg(sb, KERN_INFO, "use dax instead of xip");
589 set_opt(opts->s_mount_opt, XIP);
590 fallthrough;
591 case Opt_dax:
592 #ifdef CONFIG_FS_DAX
593 ext2_msg(sb, KERN_WARNING,
594 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
595 set_opt(opts->s_mount_opt, DAX);
596 #else
597 ext2_msg(sb, KERN_INFO, "dax option not supported");
598 #endif
599 break;
600
601 #if defined(CONFIG_QUOTA)
602 case Opt_quota:
603 case Opt_usrquota:
604 set_opt(opts->s_mount_opt, USRQUOTA);
605 break;
606
607 case Opt_grpquota:
608 set_opt(opts->s_mount_opt, GRPQUOTA);
609 break;
610 #else
611 case Opt_quota:
612 case Opt_usrquota:
613 case Opt_grpquota:
614 ext2_msg(sb, KERN_INFO,
615 "quota operations not supported");
616 break;
617 #endif
618
619 case Opt_reservation:
620 set_opt(opts->s_mount_opt, RESERVATION);
621 ext2_msg(sb, KERN_INFO, "reservations ON");
622 break;
623 case Opt_noreservation:
624 clear_opt(opts->s_mount_opt, RESERVATION);
625 ext2_msg(sb, KERN_INFO, "reservations OFF");
626 break;
627 case Opt_ignore:
628 break;
629 default:
630 return 0;
631 }
632 }
633 return 1;
634 }
635
ext2_setup_super(struct super_block * sb,struct ext2_super_block * es,int read_only)636 static int ext2_setup_super (struct super_block * sb,
637 struct ext2_super_block * es,
638 int read_only)
639 {
640 int res = 0;
641 struct ext2_sb_info *sbi = EXT2_SB(sb);
642
643 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
644 ext2_msg(sb, KERN_ERR,
645 "error: revision level too high, "
646 "forcing read-only mode");
647 res = SB_RDONLY;
648 }
649 if (read_only)
650 return res;
651 if (!(sbi->s_mount_state & EXT2_VALID_FS))
652 ext2_msg(sb, KERN_WARNING,
653 "warning: mounting unchecked fs, "
654 "running e2fsck is recommended");
655 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
656 ext2_msg(sb, KERN_WARNING,
657 "warning: mounting fs with errors, "
658 "running e2fsck is recommended");
659 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
660 le16_to_cpu(es->s_mnt_count) >=
661 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
662 ext2_msg(sb, KERN_WARNING,
663 "warning: maximal mount count reached, "
664 "running e2fsck is recommended");
665 else if (le32_to_cpu(es->s_checkinterval) &&
666 (le32_to_cpu(es->s_lastcheck) +
667 le32_to_cpu(es->s_checkinterval) <=
668 ktime_get_real_seconds()))
669 ext2_msg(sb, KERN_WARNING,
670 "warning: checktime reached, "
671 "running e2fsck is recommended");
672 if (!le16_to_cpu(es->s_max_mnt_count))
673 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
674 le16_add_cpu(&es->s_mnt_count, 1);
675 if (test_opt (sb, DEBUG))
676 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
677 "bpg=%lu, ipg=%lu, mo=%04lx]",
678 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
679 sbi->s_frag_size,
680 sbi->s_groups_count,
681 EXT2_BLOCKS_PER_GROUP(sb),
682 EXT2_INODES_PER_GROUP(sb),
683 sbi->s_mount_opt);
684 return res;
685 }
686
ext2_check_descriptors(struct super_block * sb)687 static int ext2_check_descriptors(struct super_block *sb)
688 {
689 int i;
690 struct ext2_sb_info *sbi = EXT2_SB(sb);
691
692 ext2_debug ("Checking group descriptors");
693
694 for (i = 0; i < sbi->s_groups_count; i++) {
695 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
696 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
697 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i);
698
699 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
700 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
701 {
702 ext2_error (sb, "ext2_check_descriptors",
703 "Block bitmap for group %d"
704 " not in group (block %lu)!",
705 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
706 return 0;
707 }
708 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
709 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
710 {
711 ext2_error (sb, "ext2_check_descriptors",
712 "Inode bitmap for group %d"
713 " not in group (block %lu)!",
714 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
715 return 0;
716 }
717 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
718 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
719 last_block)
720 {
721 ext2_error (sb, "ext2_check_descriptors",
722 "Inode table for group %d"
723 " not in group (block %lu)!",
724 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
725 return 0;
726 }
727 }
728 return 1;
729 }
730
731 /*
732 * Maximal file size. There is a direct, and {,double-,triple-}indirect
733 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
734 * We need to be 1 filesystem block less than the 2^32 sector limit.
735 */
ext2_max_size(int bits)736 static loff_t ext2_max_size(int bits)
737 {
738 loff_t res = EXT2_NDIR_BLOCKS;
739 int meta_blocks;
740 unsigned int upper_limit;
741 unsigned int ppb = 1 << (bits-2);
742
743 /* This is calculated to be the largest file size for a
744 * dense, file such that the total number of
745 * sectors in the file, including data and all indirect blocks,
746 * does not exceed 2^32 -1
747 * __u32 i_blocks representing the total number of
748 * 512 bytes blocks of the file
749 */
750 upper_limit = (1LL << 32) - 1;
751
752 /* total blocks in file system block size */
753 upper_limit >>= (bits - 9);
754
755 /* Compute how many blocks we can address by block tree */
756 res += 1LL << (bits-2);
757 res += 1LL << (2*(bits-2));
758 res += 1LL << (3*(bits-2));
759 /* Compute how many metadata blocks are needed */
760 meta_blocks = 1;
761 meta_blocks += 1 + ppb;
762 meta_blocks += 1 + ppb + ppb * ppb;
763 /* Does block tree limit file size? */
764 if (res + meta_blocks <= upper_limit)
765 goto check_lfs;
766
767 res = upper_limit;
768 /* How many metadata blocks are needed for addressing upper_limit? */
769 upper_limit -= EXT2_NDIR_BLOCKS;
770 /* indirect blocks */
771 meta_blocks = 1;
772 upper_limit -= ppb;
773 /* double indirect blocks */
774 if (upper_limit < ppb * ppb) {
775 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
776 res -= meta_blocks;
777 goto check_lfs;
778 }
779 meta_blocks += 1 + ppb;
780 upper_limit -= ppb * ppb;
781 /* tripple indirect blocks for the rest */
782 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
783 DIV_ROUND_UP(upper_limit, ppb*ppb);
784 res -= meta_blocks;
785 check_lfs:
786 res <<= bits;
787 if (res > MAX_LFS_FILESIZE)
788 res = MAX_LFS_FILESIZE;
789
790 return res;
791 }
792
descriptor_loc(struct super_block * sb,unsigned long logic_sb_block,int nr)793 static unsigned long descriptor_loc(struct super_block *sb,
794 unsigned long logic_sb_block,
795 int nr)
796 {
797 struct ext2_sb_info *sbi = EXT2_SB(sb);
798 unsigned long bg, first_meta_bg;
799
800 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
801
802 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
803 nr < first_meta_bg)
804 return (logic_sb_block + nr + 1);
805 bg = sbi->s_desc_per_block * nr;
806
807 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);
808 }
809
ext2_fill_super(struct super_block * sb,void * data,int silent)810 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
811 {
812 struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
813 struct buffer_head * bh;
814 struct ext2_sb_info * sbi;
815 struct ext2_super_block * es;
816 struct inode *root;
817 unsigned long block;
818 unsigned long sb_block = get_sb_block(&data);
819 unsigned long logic_sb_block;
820 unsigned long offset = 0;
821 unsigned long def_mount_opts;
822 long ret = -ENOMEM;
823 int blocksize = BLOCK_SIZE;
824 int db_count;
825 int i, j;
826 __le32 features;
827 int err;
828 struct ext2_mount_options opts;
829
830 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
831 if (!sbi)
832 goto failed;
833
834 sbi->s_blockgroup_lock =
835 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
836 if (!sbi->s_blockgroup_lock) {
837 kfree(sbi);
838 goto failed;
839 }
840 sb->s_fs_info = sbi;
841 sbi->s_sb_block = sb_block;
842 sbi->s_daxdev = dax_dev;
843
844 spin_lock_init(&sbi->s_lock);
845 ret = -EINVAL;
846
847 /*
848 * See what the current blocksize for the device is, and
849 * use that as the blocksize. Otherwise (or if the blocksize
850 * is smaller than the default) use the default.
851 * This is important for devices that have a hardware
852 * sectorsize that is larger than the default.
853 */
854 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
855 if (!blocksize) {
856 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
857 goto failed_sbi;
858 }
859
860 /*
861 * If the superblock doesn't start on a hardware sector boundary,
862 * calculate the offset.
863 */
864 if (blocksize != BLOCK_SIZE) {
865 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
866 offset = (sb_block*BLOCK_SIZE) % blocksize;
867 } else {
868 logic_sb_block = sb_block;
869 }
870
871 if (!(bh = sb_bread(sb, logic_sb_block))) {
872 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
873 goto failed_sbi;
874 }
875 /*
876 * Note: s_es must be initialized as soon as possible because
877 * some ext2 macro-instructions depend on its value
878 */
879 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
880 sbi->s_es = es;
881 sb->s_magic = le16_to_cpu(es->s_magic);
882
883 if (sb->s_magic != EXT2_SUPER_MAGIC)
884 goto cantfind_ext2;
885
886 opts.s_mount_opt = 0;
887 /* Set defaults before we parse the mount options */
888 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
889 if (def_mount_opts & EXT2_DEFM_DEBUG)
890 set_opt(opts.s_mount_opt, DEBUG);
891 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
892 set_opt(opts.s_mount_opt, GRPID);
893 if (def_mount_opts & EXT2_DEFM_UID16)
894 set_opt(opts.s_mount_opt, NO_UID32);
895 #ifdef CONFIG_EXT2_FS_XATTR
896 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
897 set_opt(opts.s_mount_opt, XATTR_USER);
898 #endif
899 #ifdef CONFIG_EXT2_FS_POSIX_ACL
900 if (def_mount_opts & EXT2_DEFM_ACL)
901 set_opt(opts.s_mount_opt, POSIX_ACL);
902 #endif
903
904 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
905 set_opt(opts.s_mount_opt, ERRORS_PANIC);
906 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
907 set_opt(opts.s_mount_opt, ERRORS_CONT);
908 else
909 set_opt(opts.s_mount_opt, ERRORS_RO);
910
911 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
912 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
913
914 set_opt(opts.s_mount_opt, RESERVATION);
915
916 if (!parse_options((char *) data, sb, &opts))
917 goto failed_mount;
918
919 sbi->s_mount_opt = opts.s_mount_opt;
920 sbi->s_resuid = opts.s_resuid;
921 sbi->s_resgid = opts.s_resgid;
922
923 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
924 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
925 sb->s_iflags |= SB_I_CGROUPWB;
926
927 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
928 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
929 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
930 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
931 ext2_msg(sb, KERN_WARNING,
932 "warning: feature flags set on rev 0 fs, "
933 "running e2fsck is recommended");
934 /*
935 * Check feature flags regardless of the revision level, since we
936 * previously didn't change the revision level when setting the flags,
937 * so there is a chance incompat flags are set on a rev 0 filesystem.
938 */
939 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
940 if (features) {
941 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
942 "unsupported optional features (%x)",
943 le32_to_cpu(features));
944 goto failed_mount;
945 }
946 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
947 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
948 "unsupported optional features (%x)",
949 le32_to_cpu(features));
950 goto failed_mount;
951 }
952
953 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
954
955 if (test_opt(sb, DAX)) {
956 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
957 ext2_msg(sb, KERN_ERR,
958 "DAX unsupported by block device. Turning off DAX.");
959 clear_opt(sbi->s_mount_opt, DAX);
960 }
961 }
962
963 /* If the blocksize doesn't match, re-read the thing.. */
964 if (sb->s_blocksize != blocksize) {
965 brelse(bh);
966
967 if (!sb_set_blocksize(sb, blocksize)) {
968 ext2_msg(sb, KERN_ERR,
969 "error: bad blocksize %d", blocksize);
970 goto failed_sbi;
971 }
972
973 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
974 offset = (sb_block*BLOCK_SIZE) % blocksize;
975 bh = sb_bread(sb, logic_sb_block);
976 if(!bh) {
977 ext2_msg(sb, KERN_ERR, "error: couldn't read"
978 "superblock on 2nd try");
979 goto failed_sbi;
980 }
981 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
982 sbi->s_es = es;
983 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
984 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
985 goto failed_mount;
986 }
987 }
988
989 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
990 sb->s_max_links = EXT2_LINK_MAX;
991 sb->s_time_min = S32_MIN;
992 sb->s_time_max = S32_MAX;
993
994 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
995 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
996 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
997 } else {
998 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
999 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1000 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1001 !is_power_of_2(sbi->s_inode_size) ||
1002 (sbi->s_inode_size > blocksize)) {
1003 ext2_msg(sb, KERN_ERR,
1004 "error: unsupported inode size: %d",
1005 sbi->s_inode_size);
1006 goto failed_mount;
1007 }
1008 }
1009
1010 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
1011 le32_to_cpu(es->s_log_frag_size);
1012 if (sbi->s_frag_size == 0)
1013 goto cantfind_ext2;
1014 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
1015
1016 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1017 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1018 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1019
1020 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1021 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1022 goto cantfind_ext2;
1023 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1024 sbi->s_inodes_per_block;
1025 sbi->s_desc_per_block = sb->s_blocksize /
1026 sizeof (struct ext2_group_desc);
1027 sbi->s_sbh = bh;
1028 sbi->s_mount_state = le16_to_cpu(es->s_state);
1029 sbi->s_addr_per_block_bits =
1030 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1031 sbi->s_desc_per_block_bits =
1032 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1033
1034 if (sb->s_magic != EXT2_SUPER_MAGIC)
1035 goto cantfind_ext2;
1036
1037 if (sb->s_blocksize != bh->b_size) {
1038 if (!silent)
1039 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1040 goto failed_mount;
1041 }
1042
1043 if (sb->s_blocksize != sbi->s_frag_size) {
1044 ext2_msg(sb, KERN_ERR,
1045 "error: fragsize %lu != blocksize %lu"
1046 "(not supported yet)",
1047 sbi->s_frag_size, sb->s_blocksize);
1048 goto failed_mount;
1049 }
1050
1051 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1052 ext2_msg(sb, KERN_ERR,
1053 "error: #blocks per group too big: %lu",
1054 sbi->s_blocks_per_group);
1055 goto failed_mount;
1056 }
1057 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
1058 ext2_msg(sb, KERN_ERR,
1059 "error: #fragments per group too big: %lu",
1060 sbi->s_frags_per_group);
1061 goto failed_mount;
1062 }
1063 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
1064 sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1065 ext2_msg(sb, KERN_ERR,
1066 "error: invalid #inodes per group: %lu",
1067 sbi->s_inodes_per_group);
1068 goto failed_mount;
1069 }
1070
1071 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1072 goto cantfind_ext2;
1073 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1074 le32_to_cpu(es->s_first_data_block) - 1)
1075 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1076 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=
1077 le32_to_cpu(es->s_inodes_count)) {
1078 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",
1079 le32_to_cpu(es->s_inodes_count),
1080 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);
1081 goto failed_mount;
1082 }
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_array (db_count,
1086 sizeof(struct buffer_head *),
1087 GFP_KERNEL);
1088 if (sbi->s_group_desc == NULL) {
1089 ret = -ENOMEM;
1090 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1091 goto failed_mount;
1092 }
1093 bgl_lock_init(sbi->s_blockgroup_lock);
1094 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1095 if (!sbi->s_debts) {
1096 ret = -ENOMEM;
1097 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1098 goto failed_mount_group_desc;
1099 }
1100 for (i = 0; i < db_count; i++) {
1101 block = descriptor_loc(sb, logic_sb_block, i);
1102 sbi->s_group_desc[i] = sb_bread(sb, block);
1103 if (!sbi->s_group_desc[i]) {
1104 for (j = 0; j < i; j++)
1105 brelse (sbi->s_group_desc[j]);
1106 ext2_msg(sb, KERN_ERR,
1107 "error: unable to read group descriptors");
1108 goto failed_mount_group_desc;
1109 }
1110 }
1111 if (!ext2_check_descriptors (sb)) {
1112 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1113 goto failed_mount2;
1114 }
1115 sbi->s_gdb_count = db_count;
1116 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1117 spin_lock_init(&sbi->s_next_gen_lock);
1118
1119 /* per fileystem reservation list head & lock */
1120 spin_lock_init(&sbi->s_rsv_window_lock);
1121 sbi->s_rsv_window_root = RB_ROOT;
1122 /*
1123 * Add a single, static dummy reservation to the start of the
1124 * reservation window list --- it gives us a placeholder for
1125 * append-at-start-of-list which makes the allocation logic
1126 * _much_ simpler.
1127 */
1128 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1129 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1130 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1131 sbi->s_rsv_window_head.rsv_goal_size = 0;
1132 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1133
1134 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1135 ext2_count_free_blocks(sb), GFP_KERNEL);
1136 if (!err) {
1137 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1138 ext2_count_free_inodes(sb), GFP_KERNEL);
1139 }
1140 if (!err) {
1141 err = percpu_counter_init(&sbi->s_dirs_counter,
1142 ext2_count_dirs(sb), GFP_KERNEL);
1143 }
1144 if (err) {
1145 ret = err;
1146 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1147 goto failed_mount3;
1148 }
1149
1150 #ifdef CONFIG_EXT2_FS_XATTR
1151 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1152 if (!sbi->s_ea_block_cache) {
1153 ret = -ENOMEM;
1154 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1155 goto failed_mount3;
1156 }
1157 #endif
1158 /*
1159 * set up enough so that it can read an inode
1160 */
1161 sb->s_op = &ext2_sops;
1162 sb->s_export_op = &ext2_export_ops;
1163 sb->s_xattr = ext2_xattr_handlers;
1164
1165 #ifdef CONFIG_QUOTA
1166 sb->dq_op = &dquot_operations;
1167 sb->s_qcop = &ext2_quotactl_ops;
1168 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1169 #endif
1170
1171 root = ext2_iget(sb, EXT2_ROOT_INO);
1172 if (IS_ERR(root)) {
1173 ret = PTR_ERR(root);
1174 goto failed_mount3;
1175 }
1176 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1177 iput(root);
1178 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1179 goto failed_mount3;
1180 }
1181
1182 sb->s_root = d_make_root(root);
1183 if (!sb->s_root) {
1184 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1185 ret = -ENOMEM;
1186 goto failed_mount3;
1187 }
1188 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1189 ext2_msg(sb, KERN_WARNING,
1190 "warning: mounting ext3 filesystem as ext2");
1191 if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1192 sb->s_flags |= SB_RDONLY;
1193 ext2_write_super(sb);
1194 return 0;
1195
1196 cantfind_ext2:
1197 if (!silent)
1198 ext2_msg(sb, KERN_ERR,
1199 "error: can't find an ext2 filesystem on dev %s.",
1200 sb->s_id);
1201 goto failed_mount;
1202 failed_mount3:
1203 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1204 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1205 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1206 percpu_counter_destroy(&sbi->s_dirs_counter);
1207 failed_mount2:
1208 for (i = 0; i < db_count; i++)
1209 brelse(sbi->s_group_desc[i]);
1210 failed_mount_group_desc:
1211 kfree(sbi->s_group_desc);
1212 kfree(sbi->s_debts);
1213 failed_mount:
1214 brelse(bh);
1215 failed_sbi:
1216 sb->s_fs_info = NULL;
1217 kfree(sbi->s_blockgroup_lock);
1218 kfree(sbi);
1219 failed:
1220 fs_put_dax(dax_dev);
1221 return ret;
1222 }
1223
ext2_clear_super_error(struct super_block * sb)1224 static void ext2_clear_super_error(struct super_block *sb)
1225 {
1226 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1227
1228 if (buffer_write_io_error(sbh)) {
1229 /*
1230 * Oh, dear. A previous attempt to write the
1231 * superblock failed. This could happen because the
1232 * USB device was yanked out. Or it could happen to
1233 * be a transient write error and maybe the block will
1234 * be remapped. Nothing we can do but to retry the
1235 * write and hope for the best.
1236 */
1237 ext2_msg(sb, KERN_ERR,
1238 "previous I/O error to superblock detected");
1239 clear_buffer_write_io_error(sbh);
1240 set_buffer_uptodate(sbh);
1241 }
1242 }
1243
ext2_sync_super(struct super_block * sb,struct ext2_super_block * es,int wait)1244 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1245 int wait)
1246 {
1247 ext2_clear_super_error(sb);
1248 spin_lock(&EXT2_SB(sb)->s_lock);
1249 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1250 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1251 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1252 /* unlock before we do IO */
1253 spin_unlock(&EXT2_SB(sb)->s_lock);
1254 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1255 if (wait)
1256 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1257 }
1258
1259 /*
1260 * In the second extended file system, it is not necessary to
1261 * write the super block since we use a mapping of the
1262 * disk super block in a buffer.
1263 *
1264 * However, this function is still used to set the fs valid
1265 * flags to 0. We need to set this flag to 0 since the fs
1266 * may have been checked while mounted and e2fsck may have
1267 * set s_state to EXT2_VALID_FS after some corrections.
1268 */
ext2_sync_fs(struct super_block * sb,int wait)1269 static int ext2_sync_fs(struct super_block *sb, int wait)
1270 {
1271 struct ext2_sb_info *sbi = EXT2_SB(sb);
1272 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1273
1274 /*
1275 * Write quota structures to quota file, sync_blockdev() will write
1276 * them to disk later
1277 */
1278 dquot_writeback_dquots(sb, -1);
1279
1280 spin_lock(&sbi->s_lock);
1281 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1282 ext2_debug("setting valid to 0\n");
1283 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1284 }
1285 spin_unlock(&sbi->s_lock);
1286 ext2_sync_super(sb, es, wait);
1287 return 0;
1288 }
1289
ext2_freeze(struct super_block * sb)1290 static int ext2_freeze(struct super_block *sb)
1291 {
1292 struct ext2_sb_info *sbi = EXT2_SB(sb);
1293
1294 /*
1295 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1296 * because we have unattached inodes and thus filesystem is not fully
1297 * consistent.
1298 */
1299 if (atomic_long_read(&sb->s_remove_count)) {
1300 ext2_sync_fs(sb, 1);
1301 return 0;
1302 }
1303 /* Set EXT2_FS_VALID flag */
1304 spin_lock(&sbi->s_lock);
1305 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1306 spin_unlock(&sbi->s_lock);
1307 ext2_sync_super(sb, sbi->s_es, 1);
1308
1309 return 0;
1310 }
1311
ext2_unfreeze(struct super_block * sb)1312 static int ext2_unfreeze(struct super_block *sb)
1313 {
1314 /* Just write sb to clear EXT2_VALID_FS flag */
1315 ext2_write_super(sb);
1316
1317 return 0;
1318 }
1319
ext2_write_super(struct super_block * sb)1320 static void ext2_write_super(struct super_block *sb)
1321 {
1322 if (!sb_rdonly(sb))
1323 ext2_sync_fs(sb, 1);
1324 }
1325
ext2_remount(struct super_block * sb,int * flags,char * data)1326 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1327 {
1328 struct ext2_sb_info * sbi = EXT2_SB(sb);
1329 struct ext2_super_block * es;
1330 struct ext2_mount_options new_opts;
1331 int err;
1332
1333 sync_filesystem(sb);
1334
1335 spin_lock(&sbi->s_lock);
1336 new_opts.s_mount_opt = sbi->s_mount_opt;
1337 new_opts.s_resuid = sbi->s_resuid;
1338 new_opts.s_resgid = sbi->s_resgid;
1339 spin_unlock(&sbi->s_lock);
1340
1341 if (!parse_options(data, sb, &new_opts))
1342 return -EINVAL;
1343
1344 spin_lock(&sbi->s_lock);
1345 es = sbi->s_es;
1346 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1347 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1348 "dax flag with busy inodes while remounting");
1349 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1350 }
1351 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1352 goto out_set;
1353 if (*flags & SB_RDONLY) {
1354 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1355 !(sbi->s_mount_state & EXT2_VALID_FS))
1356 goto out_set;
1357
1358 /*
1359 * OK, we are remounting a valid rw partition rdonly, so set
1360 * the rdonly flag and then mark the partition as valid again.
1361 */
1362 es->s_state = cpu_to_le16(sbi->s_mount_state);
1363 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1364 spin_unlock(&sbi->s_lock);
1365
1366 err = dquot_suspend(sb, -1);
1367 if (err < 0)
1368 return err;
1369
1370 ext2_sync_super(sb, es, 1);
1371 } else {
1372 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1373 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1374 if (ret) {
1375 spin_unlock(&sbi->s_lock);
1376 ext2_msg(sb, KERN_WARNING,
1377 "warning: couldn't remount RDWR because of "
1378 "unsupported optional features (%x).",
1379 le32_to_cpu(ret));
1380 return -EROFS;
1381 }
1382 /*
1383 * Mounting a RDONLY partition read-write, so reread and
1384 * store the current valid flag. (It may have been changed
1385 * by e2fsck since we originally mounted the partition.)
1386 */
1387 sbi->s_mount_state = le16_to_cpu(es->s_state);
1388 if (!ext2_setup_super (sb, es, 0))
1389 sb->s_flags &= ~SB_RDONLY;
1390 spin_unlock(&sbi->s_lock);
1391
1392 ext2_write_super(sb);
1393
1394 dquot_resume(sb, -1);
1395 }
1396
1397 spin_lock(&sbi->s_lock);
1398 out_set:
1399 sbi->s_mount_opt = new_opts.s_mount_opt;
1400 sbi->s_resuid = new_opts.s_resuid;
1401 sbi->s_resgid = new_opts.s_resgid;
1402 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1403 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
1404 spin_unlock(&sbi->s_lock);
1405
1406 return 0;
1407 }
1408
ext2_statfs(struct dentry * dentry,struct kstatfs * buf)1409 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1410 {
1411 struct super_block *sb = dentry->d_sb;
1412 struct ext2_sb_info *sbi = EXT2_SB(sb);
1413 struct ext2_super_block *es = sbi->s_es;
1414 u64 fsid;
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 fsid = le64_to_cpup((void *)es->s_uuid) ^
1469 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1470 buf->f_fsid = u64_to_fsid(fsid);
1471 spin_unlock(&sbi->s_lock);
1472 return 0;
1473 }
1474
ext2_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)1475 static struct dentry *ext2_mount(struct file_system_type *fs_type,
1476 int flags, const char *dev_name, void *data)
1477 {
1478 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1479 }
1480
1481 #ifdef CONFIG_QUOTA
1482
1483 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1484 * acquiring the locks... As quota files are never truncated and quota code
1485 * itself serializes the operations (and no one else should touch the files)
1486 * 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)1487 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1488 size_t len, loff_t off)
1489 {
1490 struct inode *inode = sb_dqopt(sb)->files[type];
1491 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1492 int err = 0;
1493 int offset = off & (sb->s_blocksize - 1);
1494 int tocopy;
1495 size_t toread;
1496 struct buffer_head tmp_bh;
1497 struct buffer_head *bh;
1498 loff_t i_size = i_size_read(inode);
1499
1500 if (off > i_size)
1501 return 0;
1502 if (off+len > i_size)
1503 len = i_size-off;
1504 toread = len;
1505 while (toread > 0) {
1506 tocopy = sb->s_blocksize - offset < toread ?
1507 sb->s_blocksize - offset : toread;
1508
1509 tmp_bh.b_state = 0;
1510 tmp_bh.b_size = sb->s_blocksize;
1511 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1512 if (err < 0)
1513 return err;
1514 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1515 memset(data, 0, tocopy);
1516 else {
1517 bh = sb_bread(sb, tmp_bh.b_blocknr);
1518 if (!bh)
1519 return -EIO;
1520 memcpy(data, bh->b_data+offset, tocopy);
1521 brelse(bh);
1522 }
1523 offset = 0;
1524 toread -= tocopy;
1525 data += tocopy;
1526 blk++;
1527 }
1528 return len;
1529 }
1530
1531 /* Write to quotafile */
ext2_quota_write(struct super_block * sb,int type,const char * data,size_t len,loff_t off)1532 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1533 const char *data, size_t len, loff_t off)
1534 {
1535 struct inode *inode = sb_dqopt(sb)->files[type];
1536 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1537 int err = 0;
1538 int offset = off & (sb->s_blocksize - 1);
1539 int tocopy;
1540 size_t towrite = len;
1541 struct buffer_head tmp_bh;
1542 struct buffer_head *bh;
1543
1544 while (towrite > 0) {
1545 tocopy = sb->s_blocksize - offset < towrite ?
1546 sb->s_blocksize - offset : towrite;
1547
1548 tmp_bh.b_state = 0;
1549 tmp_bh.b_size = sb->s_blocksize;
1550 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1551 if (err < 0)
1552 goto out;
1553 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1554 bh = sb_bread(sb, tmp_bh.b_blocknr);
1555 else
1556 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1557 if (unlikely(!bh)) {
1558 err = -EIO;
1559 goto out;
1560 }
1561 lock_buffer(bh);
1562 memcpy(bh->b_data+offset, data, tocopy);
1563 flush_dcache_page(bh->b_page);
1564 set_buffer_uptodate(bh);
1565 mark_buffer_dirty(bh);
1566 unlock_buffer(bh);
1567 brelse(bh);
1568 offset = 0;
1569 towrite -= tocopy;
1570 data += tocopy;
1571 blk++;
1572 }
1573 out:
1574 if (len == towrite)
1575 return err;
1576 if (inode->i_size < off+len-towrite)
1577 i_size_write(inode, off+len-towrite);
1578 inode_inc_iversion(inode);
1579 inode->i_mtime = inode->i_ctime = current_time(inode);
1580 mark_inode_dirty(inode);
1581 return len - towrite;
1582 }
1583
ext2_quota_on(struct super_block * sb,int type,int format_id,const struct path * path)1584 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1585 const struct path *path)
1586 {
1587 int err;
1588 struct inode *inode;
1589
1590 err = dquot_quota_on(sb, type, format_id, path);
1591 if (err)
1592 return err;
1593
1594 inode = d_inode(path->dentry);
1595 inode_lock(inode);
1596 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1597 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1598 S_NOATIME | S_IMMUTABLE);
1599 inode_unlock(inode);
1600 mark_inode_dirty(inode);
1601
1602 return 0;
1603 }
1604
ext2_quota_off(struct super_block * sb,int type)1605 static int ext2_quota_off(struct super_block *sb, int type)
1606 {
1607 struct inode *inode = sb_dqopt(sb)->files[type];
1608 int err;
1609
1610 if (!inode || !igrab(inode))
1611 goto out;
1612
1613 err = dquot_quota_off(sb, type);
1614 if (err)
1615 goto out_put;
1616
1617 inode_lock(inode);
1618 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1619 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1620 inode_unlock(inode);
1621 mark_inode_dirty(inode);
1622 out_put:
1623 iput(inode);
1624 return err;
1625 out:
1626 return dquot_quota_off(sb, type);
1627 }
1628
1629 #endif
1630
1631 static struct file_system_type ext2_fs_type = {
1632 .owner = THIS_MODULE,
1633 .name = "ext2",
1634 .mount = ext2_mount,
1635 .kill_sb = kill_block_super,
1636 .fs_flags = FS_REQUIRES_DEV,
1637 };
1638 MODULE_ALIAS_FS("ext2");
1639
init_ext2_fs(void)1640 static int __init init_ext2_fs(void)
1641 {
1642 int err;
1643
1644 err = init_inodecache();
1645 if (err)
1646 return err;
1647 err = register_filesystem(&ext2_fs_type);
1648 if (err)
1649 goto out;
1650 return 0;
1651 out:
1652 destroy_inodecache();
1653 return err;
1654 }
1655
exit_ext2_fs(void)1656 static void __exit exit_ext2_fs(void)
1657 {
1658 unregister_filesystem(&ext2_fs_type);
1659 destroy_inodecache();
1660 }
1661
1662 MODULE_AUTHOR("Remy Card and others");
1663 MODULE_DESCRIPTION("Second Extended Filesystem");
1664 MODULE_LICENSE("GPL");
1665 module_init(init_ext2_fs)
1666 module_exit(exit_ext2_fs)
1667