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 <linux/iversion.h>
37 #include "ext2.h"
38 #include "xattr.h"
39 #include "acl.h"
40
41 static void ext2_write_super(struct super_block *sb);
42 static int ext2_remount (struct super_block * sb, int * flags, char * data);
43 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
44 static int ext2_sync_fs(struct super_block *sb, int wait);
45 static int ext2_freeze(struct super_block *sb);
46 static int ext2_unfreeze(struct super_block *sb);
47
ext2_error(struct super_block * sb,const char * function,const char * fmt,...)48 void ext2_error(struct super_block *sb, const char *function,
49 const char *fmt, ...)
50 {
51 struct va_format vaf;
52 va_list args;
53 struct ext2_sb_info *sbi = EXT2_SB(sb);
54 struct ext2_super_block *es = sbi->s_es;
55
56 if (!sb_rdonly(sb)) {
57 spin_lock(&sbi->s_lock);
58 sbi->s_mount_state |= EXT2_ERROR_FS;
59 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
60 spin_unlock(&sbi->s_lock);
61 ext2_sync_super(sb, es, 1);
62 }
63
64 va_start(args, fmt);
65
66 vaf.fmt = fmt;
67 vaf.va = &args;
68
69 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
70 sb->s_id, function, &vaf);
71
72 va_end(args);
73
74 if (test_opt(sb, ERRORS_PANIC))
75 panic("EXT2-fs: panic from previous error\n");
76 if (test_opt(sb, ERRORS_RO)) {
77 ext2_msg(sb, KERN_CRIT,
78 "error: remounting filesystem read-only");
79 sb->s_flags |= SB_RDONLY;
80 }
81 }
82
ext2_msg(struct super_block * sb,const char * prefix,const char * fmt,...)83 void ext2_msg(struct super_block *sb, const char *prefix,
84 const char *fmt, ...)
85 {
86 struct va_format vaf;
87 va_list args;
88
89 va_start(args, fmt);
90
91 vaf.fmt = fmt;
92 vaf.va = &args;
93
94 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
95
96 va_end(args);
97 }
98
99 /*
100 * This must be called with sbi->s_lock held.
101 */
ext2_update_dynamic_rev(struct super_block * sb)102 void ext2_update_dynamic_rev(struct super_block *sb)
103 {
104 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
105
106 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
107 return;
108
109 ext2_msg(sb, KERN_WARNING,
110 "warning: updating to rev %d because of "
111 "new feature flag, running e2fsck is recommended",
112 EXT2_DYNAMIC_REV);
113
114 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
115 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
116 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
117 /* leave es->s_feature_*compat flags alone */
118 /* es->s_uuid will be set by e2fsck if empty */
119
120 /*
121 * The rest of the superblock fields should be zero, and if not it
122 * means they are likely already in use, so leave them alone. We
123 * can leave it up to e2fsck to clean up any inconsistencies there.
124 */
125 }
126
127 #ifdef CONFIG_QUOTA
128 static int ext2_quota_off(struct super_block *sb, int type);
129
ext2_quota_off_umount(struct super_block * sb)130 static void ext2_quota_off_umount(struct super_block *sb)
131 {
132 int type;
133
134 for (type = 0; type < MAXQUOTAS; type++)
135 ext2_quota_off(sb, type);
136 }
137 #else
ext2_quota_off_umount(struct super_block * sb)138 static inline void ext2_quota_off_umount(struct super_block *sb)
139 {
140 }
141 #endif
142
ext2_put_super(struct super_block * sb)143 static void ext2_put_super (struct super_block * sb)
144 {
145 int db_count;
146 int i;
147 struct ext2_sb_info *sbi = EXT2_SB(sb);
148
149 ext2_quota_off_umount(sb);
150
151 if (sbi->s_ea_block_cache) {
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 if (sbi->s_group_desc[i])
166 brelse (sbi->s_group_desc[i]);
167 kfree(sbi->s_group_desc);
168 kfree(sbi->s_debts);
169 percpu_counter_destroy(&sbi->s_freeblocks_counter);
170 percpu_counter_destroy(&sbi->s_freeinodes_counter);
171 percpu_counter_destroy(&sbi->s_dirs_counter);
172 brelse (sbi->s_sbh);
173 sb->s_fs_info = NULL;
174 kfree(sbi->s_blockgroup_lock);
175 fs_put_dax(sbi->s_daxdev);
176 kfree(sbi);
177 }
178
179 static struct kmem_cache * ext2_inode_cachep;
180
ext2_alloc_inode(struct super_block * sb)181 static struct inode *ext2_alloc_inode(struct super_block *sb)
182 {
183 struct ext2_inode_info *ei;
184 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
185 if (!ei)
186 return NULL;
187 ei->i_block_alloc_info = NULL;
188 inode_set_iversion(&ei->vfs_inode, 1);
189 #ifdef CONFIG_QUOTA
190 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
191 #endif
192
193 return &ei->vfs_inode;
194 }
195
ext2_i_callback(struct rcu_head * head)196 static void ext2_i_callback(struct rcu_head *head)
197 {
198 struct inode *inode = container_of(head, struct inode, i_rcu);
199 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
200 }
201
ext2_destroy_inode(struct inode * inode)202 static void ext2_destroy_inode(struct inode *inode)
203 {
204 call_rcu(&inode->i_rcu, ext2_i_callback);
205 }
206
init_once(void * foo)207 static void init_once(void *foo)
208 {
209 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
210
211 rwlock_init(&ei->i_meta_lock);
212 #ifdef CONFIG_EXT2_FS_XATTR
213 init_rwsem(&ei->xattr_sem);
214 #endif
215 mutex_init(&ei->truncate_mutex);
216 #ifdef CONFIG_FS_DAX
217 init_rwsem(&ei->dax_sem);
218 #endif
219 inode_init_once(&ei->vfs_inode);
220 }
221
init_inodecache(void)222 static int __init init_inodecache(void)
223 {
224 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",
225 sizeof(struct ext2_inode_info), 0,
226 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
227 SLAB_ACCOUNT),
228 offsetof(struct ext2_inode_info, i_data),
229 sizeof_field(struct ext2_inode_info, i_data),
230 init_once);
231 if (ext2_inode_cachep == NULL)
232 return -ENOMEM;
233 return 0;
234 }
235
destroy_inodecache(void)236 static void destroy_inodecache(void)
237 {
238 /*
239 * Make sure all delayed rcu free inodes are flushed before we
240 * destroy cache.
241 */
242 rcu_barrier();
243 kmem_cache_destroy(ext2_inode_cachep);
244 }
245
ext2_show_options(struct seq_file * seq,struct dentry * root)246 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
247 {
248 struct super_block *sb = root->d_sb;
249 struct ext2_sb_info *sbi = EXT2_SB(sb);
250 struct ext2_super_block *es = sbi->s_es;
251 unsigned long def_mount_opts;
252
253 spin_lock(&sbi->s_lock);
254 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
255
256 if (sbi->s_sb_block != 1)
257 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
258 if (test_opt(sb, MINIX_DF))
259 seq_puts(seq, ",minixdf");
260 if (test_opt(sb, GRPID))
261 seq_puts(seq, ",grpid");
262 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
263 seq_puts(seq, ",nogrpid");
264 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
265 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
266 seq_printf(seq, ",resuid=%u",
267 from_kuid_munged(&init_user_ns, sbi->s_resuid));
268 }
269 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
270 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
271 seq_printf(seq, ",resgid=%u",
272 from_kgid_munged(&init_user_ns, sbi->s_resgid));
273 }
274 if (test_opt(sb, ERRORS_RO)) {
275 int def_errors = le16_to_cpu(es->s_errors);
276
277 if (def_errors == EXT2_ERRORS_PANIC ||
278 def_errors == EXT2_ERRORS_CONTINUE) {
279 seq_puts(seq, ",errors=remount-ro");
280 }
281 }
282 if (test_opt(sb, ERRORS_CONT))
283 seq_puts(seq, ",errors=continue");
284 if (test_opt(sb, ERRORS_PANIC))
285 seq_puts(seq, ",errors=panic");
286 if (test_opt(sb, NO_UID32))
287 seq_puts(seq, ",nouid32");
288 if (test_opt(sb, DEBUG))
289 seq_puts(seq, ",debug");
290 if (test_opt(sb, OLDALLOC))
291 seq_puts(seq, ",oldalloc");
292
293 #ifdef CONFIG_EXT2_FS_XATTR
294 if (test_opt(sb, XATTR_USER))
295 seq_puts(seq, ",user_xattr");
296 if (!test_opt(sb, XATTR_USER) &&
297 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
298 seq_puts(seq, ",nouser_xattr");
299 }
300 #endif
301
302 #ifdef CONFIG_EXT2_FS_POSIX_ACL
303 if (test_opt(sb, POSIX_ACL))
304 seq_puts(seq, ",acl");
305 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
306 seq_puts(seq, ",noacl");
307 #endif
308
309 if (test_opt(sb, NOBH))
310 seq_puts(seq, ",nobh");
311
312 #if defined(CONFIG_QUOTA)
313 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
314 seq_puts(seq, ",usrquota");
315
316 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
317 seq_puts(seq, ",grpquota");
318 #endif
319
320 #ifdef CONFIG_FS_DAX
321 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
322 seq_puts(seq, ",xip");
323 if (sbi->s_mount_opt & EXT2_MOUNT_DAX)
324 seq_puts(seq, ",dax");
325 #endif
326
327 if (!test_opt(sb, RESERVATION))
328 seq_puts(seq, ",noreservation");
329
330 spin_unlock(&sbi->s_lock);
331 return 0;
332 }
333
334 #ifdef CONFIG_QUOTA
335 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
336 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
337 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
338 const struct path *path);
ext2_get_dquots(struct inode * inode)339 static struct dquot **ext2_get_dquots(struct inode *inode)
340 {
341 return EXT2_I(inode)->i_dquot;
342 }
343
344 static const struct quotactl_ops ext2_quotactl_ops = {
345 .quota_on = ext2_quota_on,
346 .quota_off = ext2_quota_off,
347 .quota_sync = dquot_quota_sync,
348 .get_state = dquot_get_state,
349 .set_info = dquot_set_dqinfo,
350 .get_dqblk = dquot_get_dqblk,
351 .set_dqblk = dquot_set_dqblk,
352 .get_nextdqblk = dquot_get_next_dqblk,
353 };
354 #endif
355
356 static const struct super_operations ext2_sops = {
357 .alloc_inode = ext2_alloc_inode,
358 .destroy_inode = ext2_destroy_inode,
359 .write_inode = ext2_write_inode,
360 .evict_inode = ext2_evict_inode,
361 .put_super = ext2_put_super,
362 .sync_fs = ext2_sync_fs,
363 .freeze_fs = ext2_freeze,
364 .unfreeze_fs = ext2_unfreeze,
365 .statfs = ext2_statfs,
366 .remount_fs = ext2_remount,
367 .show_options = ext2_show_options,
368 #ifdef CONFIG_QUOTA
369 .quota_read = ext2_quota_read,
370 .quota_write = ext2_quota_write,
371 .get_dquots = ext2_get_dquots,
372 #endif
373 };
374
ext2_nfs_get_inode(struct super_block * sb,u64 ino,u32 generation)375 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
376 u64 ino, u32 generation)
377 {
378 struct inode *inode;
379
380 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
381 return ERR_PTR(-ESTALE);
382 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
383 return ERR_PTR(-ESTALE);
384
385 /*
386 * ext2_iget isn't quite right if the inode is currently unallocated!
387 * However ext2_iget currently does appropriate checks to handle stale
388 * inodes so everything is OK.
389 */
390 inode = ext2_iget(sb, ino);
391 if (IS_ERR(inode))
392 return ERR_CAST(inode);
393 if (generation && inode->i_generation != generation) {
394 /* we didn't find the right inode.. */
395 iput(inode);
396 return ERR_PTR(-ESTALE);
397 }
398 return inode;
399 }
400
ext2_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)401 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
402 int fh_len, int fh_type)
403 {
404 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
405 ext2_nfs_get_inode);
406 }
407
ext2_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)408 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
409 int fh_len, int fh_type)
410 {
411 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
412 ext2_nfs_get_inode);
413 }
414
415 static const struct export_operations ext2_export_ops = {
416 .fh_to_dentry = ext2_fh_to_dentry,
417 .fh_to_parent = ext2_fh_to_parent,
418 .get_parent = ext2_get_parent,
419 };
420
get_sb_block(void ** data)421 static unsigned long get_sb_block(void **data)
422 {
423 unsigned long sb_block;
424 char *options = (char *) *data;
425
426 if (!options || strncmp(options, "sb=", 3) != 0)
427 return 1; /* Default location */
428 options += 3;
429 sb_block = simple_strtoul(options, &options, 0);
430 if (*options && *options != ',') {
431 printk("EXT2-fs: Invalid sb specification: %s\n",
432 (char *) *data);
433 return 1;
434 }
435 if (*options == ',')
436 options++;
437 *data = (void *) options;
438 return sb_block;
439 }
440
441 enum {
442 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
443 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
444 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
445 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
446 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
447 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
448 };
449
450 static const match_table_t tokens = {
451 {Opt_bsd_df, "bsddf"},
452 {Opt_minix_df, "minixdf"},
453 {Opt_grpid, "grpid"},
454 {Opt_grpid, "bsdgroups"},
455 {Opt_nogrpid, "nogrpid"},
456 {Opt_nogrpid, "sysvgroups"},
457 {Opt_resgid, "resgid=%u"},
458 {Opt_resuid, "resuid=%u"},
459 {Opt_sb, "sb=%u"},
460 {Opt_err_cont, "errors=continue"},
461 {Opt_err_panic, "errors=panic"},
462 {Opt_err_ro, "errors=remount-ro"},
463 {Opt_nouid32, "nouid32"},
464 {Opt_nocheck, "check=none"},
465 {Opt_nocheck, "nocheck"},
466 {Opt_debug, "debug"},
467 {Opt_oldalloc, "oldalloc"},
468 {Opt_orlov, "orlov"},
469 {Opt_nobh, "nobh"},
470 {Opt_user_xattr, "user_xattr"},
471 {Opt_nouser_xattr, "nouser_xattr"},
472 {Opt_acl, "acl"},
473 {Opt_noacl, "noacl"},
474 {Opt_xip, "xip"},
475 {Opt_dax, "dax"},
476 {Opt_grpquota, "grpquota"},
477 {Opt_ignore, "noquota"},
478 {Opt_quota, "quota"},
479 {Opt_usrquota, "usrquota"},
480 {Opt_reservation, "reservation"},
481 {Opt_noreservation, "noreservation"},
482 {Opt_err, NULL}
483 };
484
parse_options(char * options,struct super_block * sb,struct ext2_mount_options * opts)485 static int parse_options(char *options, struct super_block *sb,
486 struct ext2_mount_options *opts)
487 {
488 char *p;
489 substring_t args[MAX_OPT_ARGS];
490 int option;
491 kuid_t uid;
492 kgid_t gid;
493
494 if (!options)
495 return 1;
496
497 while ((p = strsep (&options, ",")) != NULL) {
498 int token;
499 if (!*p)
500 continue;
501
502 token = match_token(p, tokens, args);
503 switch (token) {
504 case Opt_bsd_df:
505 clear_opt (opts->s_mount_opt, MINIX_DF);
506 break;
507 case Opt_minix_df:
508 set_opt (opts->s_mount_opt, MINIX_DF);
509 break;
510 case Opt_grpid:
511 set_opt (opts->s_mount_opt, GRPID);
512 break;
513 case Opt_nogrpid:
514 clear_opt (opts->s_mount_opt, GRPID);
515 break;
516 case Opt_resuid:
517 if (match_int(&args[0], &option))
518 return 0;
519 uid = make_kuid(current_user_ns(), option);
520 if (!uid_valid(uid)) {
521 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
522 return 0;
523
524 }
525 opts->s_resuid = uid;
526 break;
527 case Opt_resgid:
528 if (match_int(&args[0], &option))
529 return 0;
530 gid = make_kgid(current_user_ns(), option);
531 if (!gid_valid(gid)) {
532 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
533 return 0;
534 }
535 opts->s_resgid = gid;
536 break;
537 case Opt_sb:
538 /* handled by get_sb_block() instead of here */
539 /* *sb_block = match_int(&args[0]); */
540 break;
541 case Opt_err_panic:
542 clear_opt (opts->s_mount_opt, ERRORS_CONT);
543 clear_opt (opts->s_mount_opt, ERRORS_RO);
544 set_opt (opts->s_mount_opt, ERRORS_PANIC);
545 break;
546 case Opt_err_ro:
547 clear_opt (opts->s_mount_opt, ERRORS_CONT);
548 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
549 set_opt (opts->s_mount_opt, ERRORS_RO);
550 break;
551 case Opt_err_cont:
552 clear_opt (opts->s_mount_opt, ERRORS_RO);
553 clear_opt (opts->s_mount_opt, ERRORS_PANIC);
554 set_opt (opts->s_mount_opt, ERRORS_CONT);
555 break;
556 case Opt_nouid32:
557 set_opt (opts->s_mount_opt, NO_UID32);
558 break;
559 case Opt_nocheck:
560 ext2_msg(sb, KERN_WARNING,
561 "Option nocheck/check=none is deprecated and"
562 " will be removed in June 2020.");
563 clear_opt (opts->s_mount_opt, CHECK);
564 break;
565 case Opt_debug:
566 set_opt (opts->s_mount_opt, DEBUG);
567 break;
568 case Opt_oldalloc:
569 set_opt (opts->s_mount_opt, OLDALLOC);
570 break;
571 case Opt_orlov:
572 clear_opt (opts->s_mount_opt, OLDALLOC);
573 break;
574 case Opt_nobh:
575 set_opt (opts->s_mount_opt, NOBH);
576 break;
577 #ifdef CONFIG_EXT2_FS_XATTR
578 case Opt_user_xattr:
579 set_opt (opts->s_mount_opt, XATTR_USER);
580 break;
581 case Opt_nouser_xattr:
582 clear_opt (opts->s_mount_opt, XATTR_USER);
583 break;
584 #else
585 case Opt_user_xattr:
586 case Opt_nouser_xattr:
587 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
588 "not supported");
589 break;
590 #endif
591 #ifdef CONFIG_EXT2_FS_POSIX_ACL
592 case Opt_acl:
593 set_opt(opts->s_mount_opt, POSIX_ACL);
594 break;
595 case Opt_noacl:
596 clear_opt(opts->s_mount_opt, POSIX_ACL);
597 break;
598 #else
599 case Opt_acl:
600 case Opt_noacl:
601 ext2_msg(sb, KERN_INFO,
602 "(no)acl options not supported");
603 break;
604 #endif
605 case Opt_xip:
606 ext2_msg(sb, KERN_INFO, "use dax instead of xip");
607 set_opt(opts->s_mount_opt, XIP);
608 /* Fall through */
609 case Opt_dax:
610 #ifdef CONFIG_FS_DAX
611 ext2_msg(sb, KERN_WARNING,
612 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
613 set_opt(opts->s_mount_opt, DAX);
614 #else
615 ext2_msg(sb, KERN_INFO, "dax option not supported");
616 #endif
617 break;
618
619 #if defined(CONFIG_QUOTA)
620 case Opt_quota:
621 case Opt_usrquota:
622 set_opt(opts->s_mount_opt, USRQUOTA);
623 break;
624
625 case Opt_grpquota:
626 set_opt(opts->s_mount_opt, GRPQUOTA);
627 break;
628 #else
629 case Opt_quota:
630 case Opt_usrquota:
631 case Opt_grpquota:
632 ext2_msg(sb, KERN_INFO,
633 "quota operations not supported");
634 break;
635 #endif
636
637 case Opt_reservation:
638 set_opt(opts->s_mount_opt, RESERVATION);
639 ext2_msg(sb, KERN_INFO, "reservations ON");
640 break;
641 case Opt_noreservation:
642 clear_opt(opts->s_mount_opt, RESERVATION);
643 ext2_msg(sb, KERN_INFO, "reservations OFF");
644 break;
645 case Opt_ignore:
646 break;
647 default:
648 return 0;
649 }
650 }
651 return 1;
652 }
653
ext2_setup_super(struct super_block * sb,struct ext2_super_block * es,int read_only)654 static int ext2_setup_super (struct super_block * sb,
655 struct ext2_super_block * es,
656 int read_only)
657 {
658 int res = 0;
659 struct ext2_sb_info *sbi = EXT2_SB(sb);
660
661 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
662 ext2_msg(sb, KERN_ERR,
663 "error: revision level too high, "
664 "forcing read-only mode");
665 res = SB_RDONLY;
666 }
667 if (read_only)
668 return res;
669 if (!(sbi->s_mount_state & EXT2_VALID_FS))
670 ext2_msg(sb, KERN_WARNING,
671 "warning: mounting unchecked fs, "
672 "running e2fsck is recommended");
673 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
674 ext2_msg(sb, KERN_WARNING,
675 "warning: mounting fs with errors, "
676 "running e2fsck is recommended");
677 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
678 le16_to_cpu(es->s_mnt_count) >=
679 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
680 ext2_msg(sb, KERN_WARNING,
681 "warning: maximal mount count reached, "
682 "running e2fsck is recommended");
683 else if (le32_to_cpu(es->s_checkinterval) &&
684 (le32_to_cpu(es->s_lastcheck) +
685 le32_to_cpu(es->s_checkinterval) <=
686 ktime_get_real_seconds()))
687 ext2_msg(sb, KERN_WARNING,
688 "warning: checktime reached, "
689 "running e2fsck is recommended");
690 if (!le16_to_cpu(es->s_max_mnt_count))
691 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
692 le16_add_cpu(&es->s_mnt_count, 1);
693 if (test_opt (sb, DEBUG))
694 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
695 "bpg=%lu, ipg=%lu, mo=%04lx]",
696 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
697 sbi->s_frag_size,
698 sbi->s_groups_count,
699 EXT2_BLOCKS_PER_GROUP(sb),
700 EXT2_INODES_PER_GROUP(sb),
701 sbi->s_mount_opt);
702 return res;
703 }
704
ext2_check_descriptors(struct super_block * sb)705 static int ext2_check_descriptors(struct super_block *sb)
706 {
707 int i;
708 struct ext2_sb_info *sbi = EXT2_SB(sb);
709
710 ext2_debug ("Checking group descriptors");
711
712 for (i = 0; i < sbi->s_groups_count; i++) {
713 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
714 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
715 ext2_fsblk_t last_block;
716
717 if (i == sbi->s_groups_count - 1)
718 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
719 else
720 last_block = first_block +
721 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
722
723 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
724 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
725 {
726 ext2_error (sb, "ext2_check_descriptors",
727 "Block bitmap for group %d"
728 " not in group (block %lu)!",
729 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
730 return 0;
731 }
732 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
733 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
734 {
735 ext2_error (sb, "ext2_check_descriptors",
736 "Inode bitmap for group %d"
737 " not in group (block %lu)!",
738 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
739 return 0;
740 }
741 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
742 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
743 last_block)
744 {
745 ext2_error (sb, "ext2_check_descriptors",
746 "Inode table for group %d"
747 " not in group (block %lu)!",
748 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
749 return 0;
750 }
751 }
752 return 1;
753 }
754
755 /*
756 * Maximal file size. There is a direct, and {,double-,triple-}indirect
757 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
758 * We need to be 1 filesystem block less than the 2^32 sector limit.
759 */
ext2_max_size(int bits)760 static loff_t ext2_max_size(int bits)
761 {
762 loff_t res = EXT2_NDIR_BLOCKS;
763 int meta_blocks;
764 loff_t upper_limit;
765
766 /* This is calculated to be the largest file size for a
767 * dense, file such that the total number of
768 * sectors in the file, including data and all indirect blocks,
769 * does not exceed 2^32 -1
770 * __u32 i_blocks representing the total number of
771 * 512 bytes blocks of the file
772 */
773 upper_limit = (1LL << 32) - 1;
774
775 /* total blocks in file system block size */
776 upper_limit >>= (bits - 9);
777
778
779 /* indirect blocks */
780 meta_blocks = 1;
781 /* double indirect blocks */
782 meta_blocks += 1 + (1LL << (bits-2));
783 /* tripple indirect blocks */
784 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
785
786 upper_limit -= meta_blocks;
787 upper_limit <<= bits;
788
789 res += 1LL << (bits-2);
790 res += 1LL << (2*(bits-2));
791 res += 1LL << (3*(bits-2));
792 res <<= bits;
793 if (res > upper_limit)
794 res = upper_limit;
795
796 if (res > MAX_LFS_FILESIZE)
797 res = MAX_LFS_FILESIZE;
798
799 return res;
800 }
801
descriptor_loc(struct super_block * sb,unsigned long logic_sb_block,int nr)802 static unsigned long descriptor_loc(struct super_block *sb,
803 unsigned long logic_sb_block,
804 int nr)
805 {
806 struct ext2_sb_info *sbi = EXT2_SB(sb);
807 unsigned long bg, first_meta_bg;
808 int has_super = 0;
809
810 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
811
812 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
813 nr < first_meta_bg)
814 return (logic_sb_block + nr + 1);
815 bg = sbi->s_desc_per_block * nr;
816 if (ext2_bg_has_super(sb, bg))
817 has_super = 1;
818
819 return ext2_group_first_block_no(sb, bg) + has_super;
820 }
821
ext2_fill_super(struct super_block * sb,void * data,int silent)822 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
823 {
824 struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
825 struct buffer_head * bh;
826 struct ext2_sb_info * sbi;
827 struct ext2_super_block * es;
828 struct inode *root;
829 unsigned long block;
830 unsigned long sb_block = get_sb_block(&data);
831 unsigned long logic_sb_block;
832 unsigned long offset = 0;
833 unsigned long def_mount_opts;
834 long ret = -ENOMEM;
835 int blocksize = BLOCK_SIZE;
836 int db_count;
837 int i, j;
838 __le32 features;
839 int err;
840 struct ext2_mount_options opts;
841
842 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
843 if (!sbi)
844 goto failed;
845
846 sbi->s_blockgroup_lock =
847 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
848 if (!sbi->s_blockgroup_lock) {
849 kfree(sbi);
850 goto failed;
851 }
852 sb->s_fs_info = sbi;
853 sbi->s_sb_block = sb_block;
854 sbi->s_daxdev = dax_dev;
855
856 spin_lock_init(&sbi->s_lock);
857 ret = -EINVAL;
858
859 /*
860 * See what the current blocksize for the device is, and
861 * use that as the blocksize. Otherwise (or if the blocksize
862 * is smaller than the default) use the default.
863 * This is important for devices that have a hardware
864 * sectorsize that is larger than the default.
865 */
866 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
867 if (!blocksize) {
868 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
869 goto failed_sbi;
870 }
871
872 /*
873 * If the superblock doesn't start on a hardware sector boundary,
874 * calculate the offset.
875 */
876 if (blocksize != BLOCK_SIZE) {
877 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
878 offset = (sb_block*BLOCK_SIZE) % blocksize;
879 } else {
880 logic_sb_block = sb_block;
881 }
882
883 if (!(bh = sb_bread(sb, logic_sb_block))) {
884 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
885 goto failed_sbi;
886 }
887 /*
888 * Note: s_es must be initialized as soon as possible because
889 * some ext2 macro-instructions depend on its value
890 */
891 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
892 sbi->s_es = es;
893 sb->s_magic = le16_to_cpu(es->s_magic);
894
895 if (sb->s_magic != EXT2_SUPER_MAGIC)
896 goto cantfind_ext2;
897
898 /* Set defaults before we parse the mount options */
899 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
900 if (def_mount_opts & EXT2_DEFM_DEBUG)
901 set_opt(opts.s_mount_opt, DEBUG);
902 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
903 set_opt(opts.s_mount_opt, GRPID);
904 if (def_mount_opts & EXT2_DEFM_UID16)
905 set_opt(opts.s_mount_opt, NO_UID32);
906 #ifdef CONFIG_EXT2_FS_XATTR
907 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
908 set_opt(opts.s_mount_opt, XATTR_USER);
909 #endif
910 #ifdef CONFIG_EXT2_FS_POSIX_ACL
911 if (def_mount_opts & EXT2_DEFM_ACL)
912 set_opt(opts.s_mount_opt, POSIX_ACL);
913 #endif
914
915 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
916 set_opt(opts.s_mount_opt, ERRORS_PANIC);
917 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
918 set_opt(opts.s_mount_opt, ERRORS_CONT);
919 else
920 set_opt(opts.s_mount_opt, ERRORS_RO);
921
922 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
923 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
924
925 set_opt(opts.s_mount_opt, RESERVATION);
926
927 if (!parse_options((char *) data, sb, &opts))
928 goto failed_mount;
929
930 sbi->s_mount_opt = opts.s_mount_opt;
931 sbi->s_resuid = opts.s_resuid;
932 sbi->s_resgid = opts.s_resgid;
933
934 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
935 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
936 SB_POSIXACL : 0);
937 sb->s_iflags |= SB_I_CGROUPWB;
938
939 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
940 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
941 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
942 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
943 ext2_msg(sb, KERN_WARNING,
944 "warning: feature flags set on rev 0 fs, "
945 "running e2fsck is recommended");
946 /*
947 * Check feature flags regardless of the revision level, since we
948 * previously didn't change the revision level when setting the flags,
949 * so there is a chance incompat flags are set on a rev 0 filesystem.
950 */
951 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
952 if (features) {
953 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
954 "unsupported optional features (%x)",
955 le32_to_cpu(features));
956 goto failed_mount;
957 }
958 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
959 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
960 "unsupported optional features (%x)",
961 le32_to_cpu(features));
962 goto failed_mount;
963 }
964
965 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
966
967 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
968 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
969 ext2_msg(sb, KERN_ERR,
970 "DAX unsupported by block device. Turning off DAX.");
971 sbi->s_mount_opt &= ~EXT2_MOUNT_DAX;
972 }
973 }
974
975 /* If the blocksize doesn't match, re-read the thing.. */
976 if (sb->s_blocksize != blocksize) {
977 brelse(bh);
978
979 if (!sb_set_blocksize(sb, blocksize)) {
980 ext2_msg(sb, KERN_ERR,
981 "error: bad blocksize %d", blocksize);
982 goto failed_sbi;
983 }
984
985 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
986 offset = (sb_block*BLOCK_SIZE) % blocksize;
987 bh = sb_bread(sb, logic_sb_block);
988 if(!bh) {
989 ext2_msg(sb, KERN_ERR, "error: couldn't read"
990 "superblock on 2nd try");
991 goto failed_sbi;
992 }
993 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
994 sbi->s_es = es;
995 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
996 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
997 goto failed_mount;
998 }
999 }
1000
1001 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
1002 sb->s_max_links = EXT2_LINK_MAX;
1003
1004 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
1005 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
1006 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
1007 } else {
1008 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1009 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1010 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1011 !is_power_of_2(sbi->s_inode_size) ||
1012 (sbi->s_inode_size > blocksize)) {
1013 ext2_msg(sb, KERN_ERR,
1014 "error: unsupported inode size: %d",
1015 sbi->s_inode_size);
1016 goto failed_mount;
1017 }
1018 }
1019
1020 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
1021 le32_to_cpu(es->s_log_frag_size);
1022 if (sbi->s_frag_size == 0)
1023 goto cantfind_ext2;
1024 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
1025
1026 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1027 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1028 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1029
1030 if (EXT2_INODE_SIZE(sb) == 0)
1031 goto cantfind_ext2;
1032 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1033 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1034 goto cantfind_ext2;
1035 sbi->s_itb_per_group = sbi->s_inodes_per_group /
1036 sbi->s_inodes_per_block;
1037 sbi->s_desc_per_block = sb->s_blocksize /
1038 sizeof (struct ext2_group_desc);
1039 sbi->s_sbh = bh;
1040 sbi->s_mount_state = le16_to_cpu(es->s_state);
1041 sbi->s_addr_per_block_bits =
1042 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1043 sbi->s_desc_per_block_bits =
1044 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1045
1046 if (sb->s_magic != EXT2_SUPER_MAGIC)
1047 goto cantfind_ext2;
1048
1049 if (sb->s_blocksize != bh->b_size) {
1050 if (!silent)
1051 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1052 goto failed_mount;
1053 }
1054
1055 if (sb->s_blocksize != sbi->s_frag_size) {
1056 ext2_msg(sb, KERN_ERR,
1057 "error: fragsize %lu != blocksize %lu"
1058 "(not supported yet)",
1059 sbi->s_frag_size, sb->s_blocksize);
1060 goto failed_mount;
1061 }
1062
1063 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1064 ext2_msg(sb, KERN_ERR,
1065 "error: #blocks per group too big: %lu",
1066 sbi->s_blocks_per_group);
1067 goto failed_mount;
1068 }
1069 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
1070 ext2_msg(sb, KERN_ERR,
1071 "error: #fragments per group too big: %lu",
1072 sbi->s_frags_per_group);
1073 goto failed_mount;
1074 }
1075 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1076 ext2_msg(sb, KERN_ERR,
1077 "error: #inodes per group too big: %lu",
1078 sbi->s_inodes_per_group);
1079 goto failed_mount;
1080 }
1081
1082 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1083 goto cantfind_ext2;
1084 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1085 le32_to_cpu(es->s_first_data_block) - 1)
1086 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1087 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1088 EXT2_DESC_PER_BLOCK(sb);
1089 sbi->s_group_desc = kmalloc_array (db_count,
1090 sizeof(struct buffer_head *),
1091 GFP_KERNEL);
1092 if (sbi->s_group_desc == NULL) {
1093 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1094 goto failed_mount;
1095 }
1096 bgl_lock_init(sbi->s_blockgroup_lock);
1097 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1098 if (!sbi->s_debts) {
1099 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1100 goto failed_mount_group_desc;
1101 }
1102 for (i = 0; i < db_count; i++) {
1103 block = descriptor_loc(sb, logic_sb_block, i);
1104 sbi->s_group_desc[i] = sb_bread(sb, block);
1105 if (!sbi->s_group_desc[i]) {
1106 for (j = 0; j < i; j++)
1107 brelse (sbi->s_group_desc[j]);
1108 ext2_msg(sb, KERN_ERR,
1109 "error: unable to read group descriptors");
1110 goto failed_mount_group_desc;
1111 }
1112 }
1113 if (!ext2_check_descriptors (sb)) {
1114 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1115 goto failed_mount2;
1116 }
1117 sbi->s_gdb_count = db_count;
1118 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1119 spin_lock_init(&sbi->s_next_gen_lock);
1120
1121 /* per fileystem reservation list head & lock */
1122 spin_lock_init(&sbi->s_rsv_window_lock);
1123 sbi->s_rsv_window_root = RB_ROOT;
1124 /*
1125 * Add a single, static dummy reservation to the start of the
1126 * reservation window list --- it gives us a placeholder for
1127 * append-at-start-of-list which makes the allocation logic
1128 * _much_ simpler.
1129 */
1130 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1131 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1132 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1133 sbi->s_rsv_window_head.rsv_goal_size = 0;
1134 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1135
1136 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1137 ext2_count_free_blocks(sb), GFP_KERNEL);
1138 if (!err) {
1139 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1140 ext2_count_free_inodes(sb), GFP_KERNEL);
1141 }
1142 if (!err) {
1143 err = percpu_counter_init(&sbi->s_dirs_counter,
1144 ext2_count_dirs(sb), GFP_KERNEL);
1145 }
1146 if (err) {
1147 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1148 goto failed_mount3;
1149 }
1150
1151 #ifdef CONFIG_EXT2_FS_XATTR
1152 sbi->s_ea_block_cache = ext2_xattr_create_cache();
1153 if (!sbi->s_ea_block_cache) {
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 if (sbi->s_ea_block_cache)
1204 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1205 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1206 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1207 percpu_counter_destroy(&sbi->s_dirs_counter);
1208 failed_mount2:
1209 for (i = 0; i < db_count; i++)
1210 brelse(sbi->s_group_desc[i]);
1211 failed_mount_group_desc:
1212 kfree(sbi->s_group_desc);
1213 kfree(sbi->s_debts);
1214 failed_mount:
1215 brelse(bh);
1216 failed_sbi:
1217 sb->s_fs_info = NULL;
1218 kfree(sbi->s_blockgroup_lock);
1219 kfree(sbi);
1220 failed:
1221 fs_put_dax(dax_dev);
1222 return ret;
1223 }
1224
ext2_clear_super_error(struct super_block * sb)1225 static void ext2_clear_super_error(struct super_block *sb)
1226 {
1227 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1228
1229 if (buffer_write_io_error(sbh)) {
1230 /*
1231 * Oh, dear. A previous attempt to write the
1232 * superblock failed. This could happen because the
1233 * USB device was yanked out. Or it could happen to
1234 * be a transient write error and maybe the block will
1235 * be remapped. Nothing we can do but to retry the
1236 * write and hope for the best.
1237 */
1238 ext2_msg(sb, KERN_ERR,
1239 "previous I/O error to superblock detected");
1240 clear_buffer_write_io_error(sbh);
1241 set_buffer_uptodate(sbh);
1242 }
1243 }
1244
ext2_sync_super(struct super_block * sb,struct ext2_super_block * es,int wait)1245 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1246 int wait)
1247 {
1248 ext2_clear_super_error(sb);
1249 spin_lock(&EXT2_SB(sb)->s_lock);
1250 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1251 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1252 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1253 /* unlock before we do IO */
1254 spin_unlock(&EXT2_SB(sb)->s_lock);
1255 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1256 if (wait)
1257 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1258 }
1259
1260 /*
1261 * In the second extended file system, it is not necessary to
1262 * write the super block since we use a mapping of the
1263 * disk super block in a buffer.
1264 *
1265 * However, this function is still used to set the fs valid
1266 * flags to 0. We need to set this flag to 0 since the fs
1267 * may have been checked while mounted and e2fsck may have
1268 * set s_state to EXT2_VALID_FS after some corrections.
1269 */
ext2_sync_fs(struct super_block * sb,int wait)1270 static int ext2_sync_fs(struct super_block *sb, int wait)
1271 {
1272 struct ext2_sb_info *sbi = EXT2_SB(sb);
1273 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1274
1275 /*
1276 * Write quota structures to quota file, sync_blockdev() will write
1277 * them to disk later
1278 */
1279 dquot_writeback_dquots(sb, -1);
1280
1281 spin_lock(&sbi->s_lock);
1282 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1283 ext2_debug("setting valid to 0\n");
1284 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1285 }
1286 spin_unlock(&sbi->s_lock);
1287 ext2_sync_super(sb, es, wait);
1288 return 0;
1289 }
1290
ext2_freeze(struct super_block * sb)1291 static int ext2_freeze(struct super_block *sb)
1292 {
1293 struct ext2_sb_info *sbi = EXT2_SB(sb);
1294
1295 /*
1296 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1297 * because we have unattached inodes and thus filesystem is not fully
1298 * consistent.
1299 */
1300 if (atomic_long_read(&sb->s_remove_count)) {
1301 ext2_sync_fs(sb, 1);
1302 return 0;
1303 }
1304 /* Set EXT2_FS_VALID flag */
1305 spin_lock(&sbi->s_lock);
1306 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1307 spin_unlock(&sbi->s_lock);
1308 ext2_sync_super(sb, sbi->s_es, 1);
1309
1310 return 0;
1311 }
1312
ext2_unfreeze(struct super_block * sb)1313 static int ext2_unfreeze(struct super_block *sb)
1314 {
1315 /* Just write sb to clear EXT2_VALID_FS flag */
1316 ext2_write_super(sb);
1317
1318 return 0;
1319 }
1320
ext2_write_super(struct super_block * sb)1321 static void ext2_write_super(struct super_block *sb)
1322 {
1323 if (!sb_rdonly(sb))
1324 ext2_sync_fs(sb, 1);
1325 }
1326
ext2_remount(struct super_block * sb,int * flags,char * data)1327 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1328 {
1329 struct ext2_sb_info * sbi = EXT2_SB(sb);
1330 struct ext2_super_block * es;
1331 struct ext2_mount_options new_opts;
1332 int err;
1333
1334 sync_filesystem(sb);
1335
1336 spin_lock(&sbi->s_lock);
1337 new_opts.s_mount_opt = sbi->s_mount_opt;
1338 new_opts.s_resuid = sbi->s_resuid;
1339 new_opts.s_resgid = sbi->s_resgid;
1340 spin_unlock(&sbi->s_lock);
1341
1342 if (!parse_options(data, sb, &new_opts))
1343 return -EINVAL;
1344
1345 spin_lock(&sbi->s_lock);
1346 es = sbi->s_es;
1347 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1348 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1349 "dax flag with busy inodes while remounting");
1350 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1351 }
1352 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1353 goto out_set;
1354 if (*flags & SB_RDONLY) {
1355 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1356 !(sbi->s_mount_state & EXT2_VALID_FS))
1357 goto out_set;
1358
1359 /*
1360 * OK, we are remounting a valid rw partition rdonly, so set
1361 * the rdonly flag and then mark the partition as valid again.
1362 */
1363 es->s_state = cpu_to_le16(sbi->s_mount_state);
1364 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1365 spin_unlock(&sbi->s_lock);
1366
1367 err = dquot_suspend(sb, -1);
1368 if (err < 0)
1369 return err;
1370
1371 ext2_sync_super(sb, es, 1);
1372 } else {
1373 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1374 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1375 if (ret) {
1376 spin_unlock(&sbi->s_lock);
1377 ext2_msg(sb, KERN_WARNING,
1378 "warning: couldn't remount RDWR because of "
1379 "unsupported optional features (%x).",
1380 le32_to_cpu(ret));
1381 return -EROFS;
1382 }
1383 /*
1384 * Mounting a RDONLY partition read-write, so reread and
1385 * store the current valid flag. (It may have been changed
1386 * by e2fsck since we originally mounted the partition.)
1387 */
1388 sbi->s_mount_state = le16_to_cpu(es->s_state);
1389 if (!ext2_setup_super (sb, es, 0))
1390 sb->s_flags &= ~SB_RDONLY;
1391 spin_unlock(&sbi->s_lock);
1392
1393 ext2_write_super(sb);
1394
1395 dquot_resume(sb, -1);
1396 }
1397
1398 spin_lock(&sbi->s_lock);
1399 out_set:
1400 sbi->s_mount_opt = new_opts.s_mount_opt;
1401 sbi->s_resuid = new_opts.s_resuid;
1402 sbi->s_resgid = new_opts.s_resgid;
1403 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1404 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? SB_POSIXACL : 0);
1405 spin_unlock(&sbi->s_lock);
1406
1407 return 0;
1408 }
1409
ext2_statfs(struct dentry * dentry,struct kstatfs * buf)1410 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1411 {
1412 struct super_block *sb = dentry->d_sb;
1413 struct ext2_sb_info *sbi = EXT2_SB(sb);
1414 struct ext2_super_block *es = sbi->s_es;
1415 u64 fsid;
1416
1417 spin_lock(&sbi->s_lock);
1418
1419 if (test_opt (sb, MINIX_DF))
1420 sbi->s_overhead_last = 0;
1421 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1422 unsigned long i, overhead = 0;
1423 smp_rmb();
1424
1425 /*
1426 * Compute the overhead (FS structures). This is constant
1427 * for a given filesystem unless the number of block groups
1428 * changes so we cache the previous value until it does.
1429 */
1430
1431 /*
1432 * All of the blocks before first_data_block are
1433 * overhead
1434 */
1435 overhead = le32_to_cpu(es->s_first_data_block);
1436
1437 /*
1438 * Add the overhead attributed to the superblock and
1439 * block group descriptors. If the sparse superblocks
1440 * feature is turned on, then not all groups have this.
1441 */
1442 for (i = 0; i < sbi->s_groups_count; i++)
1443 overhead += ext2_bg_has_super(sb, i) +
1444 ext2_bg_num_gdb(sb, i);
1445
1446 /*
1447 * Every block group has an inode bitmap, a block
1448 * bitmap, and an inode table.
1449 */
1450 overhead += (sbi->s_groups_count *
1451 (2 + sbi->s_itb_per_group));
1452 sbi->s_overhead_last = overhead;
1453 smp_wmb();
1454 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1455 }
1456
1457 buf->f_type = EXT2_SUPER_MAGIC;
1458 buf->f_bsize = sb->s_blocksize;
1459 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1460 buf->f_bfree = ext2_count_free_blocks(sb);
1461 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1462 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1463 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1464 buf->f_bavail = 0;
1465 buf->f_files = le32_to_cpu(es->s_inodes_count);
1466 buf->f_ffree = ext2_count_free_inodes(sb);
1467 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1468 buf->f_namelen = EXT2_NAME_LEN;
1469 fsid = le64_to_cpup((void *)es->s_uuid) ^
1470 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1471 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1472 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1473 spin_unlock(&sbi->s_lock);
1474 return 0;
1475 }
1476
ext2_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)1477 static struct dentry *ext2_mount(struct file_system_type *fs_type,
1478 int flags, const char *dev_name, void *data)
1479 {
1480 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1481 }
1482
1483 #ifdef CONFIG_QUOTA
1484
1485 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1486 * acquiring the locks... As quota files are never truncated and quota code
1487 * itself serializes the operations (and no one else should touch the files)
1488 * 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)1489 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1490 size_t len, loff_t off)
1491 {
1492 struct inode *inode = sb_dqopt(sb)->files[type];
1493 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1494 int err = 0;
1495 int offset = off & (sb->s_blocksize - 1);
1496 int tocopy;
1497 size_t toread;
1498 struct buffer_head tmp_bh;
1499 struct buffer_head *bh;
1500 loff_t i_size = i_size_read(inode);
1501
1502 if (off > i_size)
1503 return 0;
1504 if (off+len > i_size)
1505 len = i_size-off;
1506 toread = len;
1507 while (toread > 0) {
1508 tocopy = sb->s_blocksize - offset < toread ?
1509 sb->s_blocksize - offset : toread;
1510
1511 tmp_bh.b_state = 0;
1512 tmp_bh.b_size = sb->s_blocksize;
1513 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1514 if (err < 0)
1515 return err;
1516 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1517 memset(data, 0, tocopy);
1518 else {
1519 bh = sb_bread(sb, tmp_bh.b_blocknr);
1520 if (!bh)
1521 return -EIO;
1522 memcpy(data, bh->b_data+offset, tocopy);
1523 brelse(bh);
1524 }
1525 offset = 0;
1526 toread -= tocopy;
1527 data += tocopy;
1528 blk++;
1529 }
1530 return len;
1531 }
1532
1533 /* Write to quotafile */
ext2_quota_write(struct super_block * sb,int type,const char * data,size_t len,loff_t off)1534 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1535 const char *data, size_t len, loff_t off)
1536 {
1537 struct inode *inode = sb_dqopt(sb)->files[type];
1538 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1539 int err = 0;
1540 int offset = off & (sb->s_blocksize - 1);
1541 int tocopy;
1542 size_t towrite = len;
1543 struct buffer_head tmp_bh;
1544 struct buffer_head *bh;
1545
1546 while (towrite > 0) {
1547 tocopy = sb->s_blocksize - offset < towrite ?
1548 sb->s_blocksize - offset : towrite;
1549
1550 tmp_bh.b_state = 0;
1551 tmp_bh.b_size = sb->s_blocksize;
1552 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1553 if (err < 0)
1554 goto out;
1555 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1556 bh = sb_bread(sb, tmp_bh.b_blocknr);
1557 else
1558 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1559 if (unlikely(!bh)) {
1560 err = -EIO;
1561 goto out;
1562 }
1563 lock_buffer(bh);
1564 memcpy(bh->b_data+offset, data, tocopy);
1565 flush_dcache_page(bh->b_page);
1566 set_buffer_uptodate(bh);
1567 mark_buffer_dirty(bh);
1568 unlock_buffer(bh);
1569 brelse(bh);
1570 offset = 0;
1571 towrite -= tocopy;
1572 data += tocopy;
1573 blk++;
1574 }
1575 out:
1576 if (len == towrite)
1577 return err;
1578 if (inode->i_size < off+len-towrite)
1579 i_size_write(inode, off+len-towrite);
1580 inode_inc_iversion(inode);
1581 inode->i_mtime = inode->i_ctime = current_time(inode);
1582 mark_inode_dirty(inode);
1583 return len - towrite;
1584 }
1585
ext2_quota_on(struct super_block * sb,int type,int format_id,const struct path * path)1586 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1587 const struct path *path)
1588 {
1589 int err;
1590 struct inode *inode;
1591
1592 err = dquot_quota_on(sb, type, format_id, path);
1593 if (err)
1594 return err;
1595
1596 inode = d_inode(path->dentry);
1597 inode_lock(inode);
1598 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1599 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1600 S_NOATIME | S_IMMUTABLE);
1601 inode_unlock(inode);
1602 mark_inode_dirty(inode);
1603
1604 return 0;
1605 }
1606
ext2_quota_off(struct super_block * sb,int type)1607 static int ext2_quota_off(struct super_block *sb, int type)
1608 {
1609 struct inode *inode = sb_dqopt(sb)->files[type];
1610 int err;
1611
1612 if (!inode || !igrab(inode))
1613 goto out;
1614
1615 err = dquot_quota_off(sb, type);
1616 if (err)
1617 goto out_put;
1618
1619 inode_lock(inode);
1620 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1621 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1622 inode_unlock(inode);
1623 mark_inode_dirty(inode);
1624 out_put:
1625 iput(inode);
1626 return err;
1627 out:
1628 return dquot_quota_off(sb, type);
1629 }
1630
1631 #endif
1632
1633 static struct file_system_type ext2_fs_type = {
1634 .owner = THIS_MODULE,
1635 .name = "ext2",
1636 .mount = ext2_mount,
1637 .kill_sb = kill_block_super,
1638 .fs_flags = FS_REQUIRES_DEV,
1639 };
1640 MODULE_ALIAS_FS("ext2");
1641
init_ext2_fs(void)1642 static int __init init_ext2_fs(void)
1643 {
1644 int err;
1645
1646 err = init_inodecache();
1647 if (err)
1648 return err;
1649 err = register_filesystem(&ext2_fs_type);
1650 if (err)
1651 goto out;
1652 return 0;
1653 out:
1654 destroy_inodecache();
1655 return err;
1656 }
1657
exit_ext2_fs(void)1658 static void __exit exit_ext2_fs(void)
1659 {
1660 unregister_filesystem(&ext2_fs_type);
1661 destroy_inodecache();
1662 }
1663
1664 MODULE_AUTHOR("Remy Card and others");
1665 MODULE_DESCRIPTION("Second Extended Filesystem");
1666 MODULE_LICENSE("GPL");
1667 module_init(init_ext2_fs)
1668 module_exit(exit_ext2_fs)
1669
