blob: d89e0b6a2d78d86f7e74772b58b98291bba3aa4a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/module.h>
20#include <linux/string.h>
Mark Bellon8fc27512005-09-06 15:16:54 -070021#include <linux/fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#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>
Christoph Hellwiga5694252007-07-17 04:04:28 -070028#include <linux/exportfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/vfs.h>
Mark Bellon8fc27512005-09-06 15:16:54 -070030#include <linux/seq_file.h>
31#include <linux/mount.h>
vignesh babud8ea6cf2007-10-16 23:27:14 -070032#include <linux/log2.h>
Jan Kara74abb982008-07-25 01:46:51 -070033#include <linux/quotaops.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <asm/uaccess.h>
35#include "ext2.h"
36#include "xattr.h"
37#include "acl.h"
Carsten Otte6d791252005-06-23 22:05:26 -070038#include "xip.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
40static void ext2_sync_super(struct super_block *sb,
Jan Blunckee6921e2010-04-14 14:38:36 +020041 struct ext2_super_block *es, int wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -070042static int ext2_remount (struct super_block * sb, int * flags, char * data);
David Howells726c3342006-06-23 02:02:58 -070043static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
Christoph Hellwig40f31dd2009-06-08 10:04:17 +020044static int ext2_sync_fs(struct super_block *sb, int wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46void ext2_error (struct super_block * sb, const char * function,
47 const char * fmt, ...)
48{
49 va_list args;
50 struct ext2_sb_info *sbi = EXT2_SB(sb);
51 struct ext2_super_block *es = sbi->s_es;
52
53 if (!(sb->s_flags & MS_RDONLY)) {
Jan Blunckc15271f2010-04-14 14:38:38 +020054 spin_lock(&sbi->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 sbi->s_mount_state |= EXT2_ERROR_FS;
Marcin Slusarz31f68e12008-04-28 02:16:00 -070056 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
Jan Blunckc15271f2010-04-14 14:38:38 +020057 spin_unlock(&sbi->s_lock);
Jan Blunckee6921e2010-04-14 14:38:36 +020058 ext2_sync_super(sb, es, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 }
60
61 va_start(args, fmt);
Alexey Fisher2314b072009-11-19 19:12:51 +010062 printk(KERN_CRIT "EXT2-fs (%s): error: %s: ", sb->s_id, function);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 vprintk(fmt, args);
64 printk("\n");
65 va_end(args);
66
67 if (test_opt(sb, ERRORS_PANIC))
Alexey Fisher2314b072009-11-19 19:12:51 +010068 panic("EXT2-fs: panic from previous error\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 if (test_opt(sb, ERRORS_RO)) {
Alexey Fisher2314b072009-11-19 19:12:51 +010070 ext2_msg(sb, KERN_CRIT,
71 "error: remounting filesystem read-only");
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 sb->s_flags |= MS_RDONLY;
73 }
74}
75
Alexey Fisher2314b072009-11-19 19:12:51 +010076void ext2_msg(struct super_block *sb, const char *prefix,
77 const char *fmt, ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078{
79 va_list args;
80
81 va_start(args, fmt);
Alexey Fisher2314b072009-11-19 19:12:51 +010082 printk("%sEXT2-fs (%s): ", prefix, sb->s_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 vprintk(fmt, args);
84 printk("\n");
85 va_end(args);
86}
87
Jan Blunckc15271f2010-04-14 14:38:38 +020088/*
89 * This must be called with sbi->s_lock held.
90 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070091void ext2_update_dynamic_rev(struct super_block *sb)
92{
93 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
94
95 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
96 return;
97
Alexey Fisher2314b072009-11-19 19:12:51 +010098 ext2_msg(sb, KERN_WARNING,
99 "warning: updating to rev %d because of "
100 "new feature flag, running e2fsck is recommended",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 EXT2_DYNAMIC_REV);
102
103 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
104 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
105 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
106 /* leave es->s_feature_*compat flags alone */
107 /* es->s_uuid will be set by e2fsck if empty */
108
109 /*
110 * The rest of the superblock fields should be zero, and if not it
111 * means they are likely already in use, so leave them alone. We
112 * can leave it up to e2fsck to clean up any inconsistencies there.
113 */
114}
115
116static void ext2_put_super (struct super_block * sb)
117{
118 int db_count;
119 int i;
120 struct ext2_sb_info *sbi = EXT2_SB(sb);
121
Christoph Hellwige0ccfd92010-05-19 07:16:42 -0400122 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
123
Christoph Hellwig8c85e122009-04-28 18:00:26 +0200124 if (sb->s_dirt)
125 ext2_write_super(sb);
126
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 ext2_xattr_put_super(sb);
128 if (!(sb->s_flags & MS_RDONLY)) {
129 struct ext2_super_block *es = sbi->s_es;
130
Jan Blunckc15271f2010-04-14 14:38:38 +0200131 spin_lock(&sbi->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 es->s_state = cpu_to_le16(sbi->s_mount_state);
Jan Blunckc15271f2010-04-14 14:38:38 +0200133 spin_unlock(&sbi->s_lock);
Jan Blunckee6921e2010-04-14 14:38:36 +0200134 ext2_sync_super(sb, es, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 }
136 db_count = sbi->s_gdb_count;
137 for (i = 0; i < db_count; i++)
138 if (sbi->s_group_desc[i])
139 brelse (sbi->s_group_desc[i]);
140 kfree(sbi->s_group_desc);
141 kfree(sbi->s_debts);
142 percpu_counter_destroy(&sbi->s_freeblocks_counter);
143 percpu_counter_destroy(&sbi->s_freeinodes_counter);
144 percpu_counter_destroy(&sbi->s_dirs_counter);
145 brelse (sbi->s_sbh);
146 sb->s_fs_info = NULL;
Pekka J Enberg18a82eb2009-01-07 18:07:19 -0800147 kfree(sbi->s_blockgroup_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 kfree(sbi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149}
150
Christoph Lametere18b8902006-12-06 20:33:20 -0800151static struct kmem_cache * ext2_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
153static struct inode *ext2_alloc_inode(struct super_block *sb)
154{
155 struct ext2_inode_info *ei;
Christoph Lametere94b1762006-12-06 20:33:17 -0800156 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 if (!ei)
158 return NULL;
Martin J. Bligha686cd82007-10-16 23:30:46 -0700159 ei->i_block_alloc_info = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 ei->vfs_inode.i_version = 1;
161 return &ei->vfs_inode;
162}
163
164static void ext2_destroy_inode(struct inode *inode)
165{
166 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
167}
168
Alexey Dobriyan51cc5062008-07-25 19:45:34 -0700169static void init_once(void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170{
171 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
172
Christoph Lametera35afb82007-05-16 22:10:57 -0700173 rwlock_init(&ei->i_meta_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174#ifdef CONFIG_EXT2_FS_XATTR
Christoph Lametera35afb82007-05-16 22:10:57 -0700175 init_rwsem(&ei->xattr_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176#endif
Martin J. Bligha686cd82007-10-16 23:30:46 -0700177 mutex_init(&ei->truncate_mutex);
Christoph Lametera35afb82007-05-16 22:10:57 -0700178 inode_init_once(&ei->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179}
Paul Mundt20c2df82007-07-20 10:11:58 +0900180
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181static int init_inodecache(void)
182{
183 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
184 sizeof(struct ext2_inode_info),
Paul Jacksonfffb60f2006-03-24 03:16:06 -0800185 0, (SLAB_RECLAIM_ACCOUNT|
186 SLAB_MEM_SPREAD),
Paul Mundt20c2df82007-07-20 10:11:58 +0900187 init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 if (ext2_inode_cachep == NULL)
189 return -ENOMEM;
190 return 0;
191}
192
193static void destroy_inodecache(void)
194{
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -0700195 kmem_cache_destroy(ext2_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196}
197
Mark Bellon8fc27512005-09-06 15:16:54 -0700198static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
199{
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700200 struct super_block *sb = vfs->mnt_sb;
201 struct ext2_sb_info *sbi = EXT2_SB(sb);
202 struct ext2_super_block *es = sbi->s_es;
203 unsigned long def_mount_opts;
Mark Bellon8fc27512005-09-06 15:16:54 -0700204
Jan Blunckc15271f2010-04-14 14:38:38 +0200205 spin_lock(&sbi->s_lock);
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700206 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
207
208 if (sbi->s_sb_block != 1)
209 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
210 if (test_opt(sb, MINIX_DF))
211 seq_puts(seq, ",minixdf");
212 if (test_opt(sb, GRPID))
Mark Bellon8fc27512005-09-06 15:16:54 -0700213 seq_puts(seq, ",grpid");
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700214 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
215 seq_puts(seq, ",nogrpid");
216 if (sbi->s_resuid != EXT2_DEF_RESUID ||
217 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
218 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
219 }
220 if (sbi->s_resgid != EXT2_DEF_RESGID ||
221 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
222 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
223 }
Aneesh Kumar K.V14e11e12008-02-06 01:36:17 -0800224 if (test_opt(sb, ERRORS_RO)) {
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700225 int def_errors = le16_to_cpu(es->s_errors);
226
227 if (def_errors == EXT2_ERRORS_PANIC ||
Aneesh Kumar K.V14e11e12008-02-06 01:36:17 -0800228 def_errors == EXT2_ERRORS_CONTINUE) {
229 seq_puts(seq, ",errors=remount-ro");
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700230 }
231 }
Aneesh Kumar K.V14e11e12008-02-06 01:36:17 -0800232 if (test_opt(sb, ERRORS_CONT))
233 seq_puts(seq, ",errors=continue");
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700234 if (test_opt(sb, ERRORS_PANIC))
235 seq_puts(seq, ",errors=panic");
236 if (test_opt(sb, NO_UID32))
237 seq_puts(seq, ",nouid32");
238 if (test_opt(sb, DEBUG))
239 seq_puts(seq, ",debug");
240 if (test_opt(sb, OLDALLOC))
241 seq_puts(seq, ",oldalloc");
242
243#ifdef CONFIG_EXT2_FS_XATTR
244 if (test_opt(sb, XATTR_USER))
245 seq_puts(seq, ",user_xattr");
246 if (!test_opt(sb, XATTR_USER) &&
247 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
248 seq_puts(seq, ",nouser_xattr");
249 }
250#endif
251
252#ifdef CONFIG_EXT2_FS_POSIX_ACL
253 if (test_opt(sb, POSIX_ACL))
254 seq_puts(seq, ",acl");
255 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
256 seq_puts(seq, ",noacl");
257#endif
258
259 if (test_opt(sb, NOBH))
260 seq_puts(seq, ",nobh");
Mark Bellon8fc27512005-09-06 15:16:54 -0700261
262#if defined(CONFIG_QUOTA)
263 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
264 seq_puts(seq, ",usrquota");
265
266 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
267 seq_puts(seq, ",grpquota");
268#endif
269
Carsten Otte83541792006-02-03 03:04:25 -0800270#if defined(CONFIG_EXT2_FS_XIP)
271 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
272 seq_puts(seq, ",xip");
273#endif
274
Miklos Szeredi35c879d2008-02-08 04:21:42 -0800275 if (!test_opt(sb, RESERVATION))
276 seq_puts(seq, ",noreservation");
277
Jan Blunckc15271f2010-04-14 14:38:38 +0200278 spin_unlock(&sbi->s_lock);
Mark Bellon8fc27512005-09-06 15:16:54 -0700279 return 0;
280}
281
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282#ifdef CONFIG_QUOTA
283static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
284static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
285#endif
286
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800287static const struct super_operations ext2_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 .alloc_inode = ext2_alloc_inode,
289 .destroy_inode = ext2_destroy_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 .write_inode = ext2_write_inode,
Al Viro72edc4d2010-06-04 23:32:28 -0400291 .evict_inode = ext2_evict_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 .put_super = ext2_put_super,
293 .write_super = ext2_write_super,
Christoph Hellwig40f31dd2009-06-08 10:04:17 +0200294 .sync_fs = ext2_sync_fs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 .statfs = ext2_statfs,
296 .remount_fs = ext2_remount,
Mark Bellon8fc27512005-09-06 15:16:54 -0700297 .show_options = ext2_show_options,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298#ifdef CONFIG_QUOTA
299 .quota_read = ext2_quota_read,
300 .quota_write = ext2_quota_write,
301#endif
302};
303
Christoph Hellwig2e4c68e2007-10-21 16:42:07 -0700304static struct inode *ext2_nfs_get_inode(struct super_block *sb,
305 u64 ino, u32 generation)
NeilBrownecaff752006-09-16 12:15:37 -0700306{
NeilBrownecaff752006-09-16 12:15:37 -0700307 struct inode *inode;
NeilBrownecaff752006-09-16 12:15:37 -0700308
309 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
310 return ERR_PTR(-ESTALE);
311 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
312 return ERR_PTR(-ESTALE);
313
314 /* iget isn't really right if the inode is currently unallocated!!
315 * ext2_read_inode currently does appropriate checks, but
316 * it might be "neater" to call ext2_get_inode first and check
317 * if the inode is valid.....
318 */
David Howells52fcf702008-02-07 00:15:35 -0800319 inode = ext2_iget(sb, ino);
320 if (IS_ERR(inode))
321 return ERR_CAST(inode);
322 if (generation && inode->i_generation != generation) {
NeilBrownecaff752006-09-16 12:15:37 -0700323 /* we didn't find the right inode.. */
324 iput(inode);
325 return ERR_PTR(-ESTALE);
326 }
Christoph Hellwig2e4c68e2007-10-21 16:42:07 -0700327 return inode;
328}
329
330static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
331 int fh_len, int fh_type)
332{
333 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
334 ext2_nfs_get_inode);
335}
336
337static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
338 int fh_len, int fh_type)
339{
340 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
341 ext2_nfs_get_inode);
NeilBrownecaff752006-09-16 12:15:37 -0700342}
343
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344/* Yes, most of these are left as NULL!!
345 * A NULL value implies the default, which works with ext2-like file
346 * systems, but can be improved upon.
347 * Currently only get_parent is required.
348 */
Christoph Hellwig39655162007-10-21 16:42:17 -0700349static const struct export_operations ext2_export_ops = {
Christoph Hellwig2e4c68e2007-10-21 16:42:07 -0700350 .fh_to_dentry = ext2_fh_to_dentry,
351 .fh_to_parent = ext2_fh_to_parent,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 .get_parent = ext2_get_parent,
353};
354
355static unsigned long get_sb_block(void **data)
356{
357 unsigned long sb_block;
358 char *options = (char *) *data;
359
360 if (!options || strncmp(options, "sb=", 3) != 0)
361 return 1; /* Default location */
362 options += 3;
363 sb_block = simple_strtoul(options, &options, 0);
364 if (*options && *options != ',') {
365 printk("EXT2-fs: Invalid sb specification: %s\n",
366 (char *) *data);
367 return 1;
368 }
369 if (*options == ',')
370 options++;
371 *data = (void *) options;
372 return sb_block;
373}
374
375enum {
376 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
Mark Bellon8fc27512005-09-06 15:16:54 -0700377 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
Adrian Bunk2860b732005-11-08 21:34:59 -0800378 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
Mark Bellon8fc27512005-09-06 15:16:54 -0700379 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
380 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
Martin J. Bligha686cd82007-10-16 23:30:46 -0700381 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382};
383
Steven Whitehousea447c092008-10-13 10:46:57 +0100384static const match_table_t tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 {Opt_bsd_df, "bsddf"},
386 {Opt_minix_df, "minixdf"},
387 {Opt_grpid, "grpid"},
388 {Opt_grpid, "bsdgroups"},
389 {Opt_nogrpid, "nogrpid"},
390 {Opt_nogrpid, "sysvgroups"},
391 {Opt_resgid, "resgid=%u"},
392 {Opt_resuid, "resuid=%u"},
393 {Opt_sb, "sb=%u"},
394 {Opt_err_cont, "errors=continue"},
395 {Opt_err_panic, "errors=panic"},
396 {Opt_err_ro, "errors=remount-ro"},
397 {Opt_nouid32, "nouid32"},
398 {Opt_nocheck, "check=none"},
399 {Opt_nocheck, "nocheck"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 {Opt_debug, "debug"},
401 {Opt_oldalloc, "oldalloc"},
402 {Opt_orlov, "orlov"},
403 {Opt_nobh, "nobh"},
404 {Opt_user_xattr, "user_xattr"},
405 {Opt_nouser_xattr, "nouser_xattr"},
406 {Opt_acl, "acl"},
407 {Opt_noacl, "noacl"},
Carsten Otte6d791252005-06-23 22:05:26 -0700408 {Opt_xip, "xip"},
Mark Bellon8fc27512005-09-06 15:16:54 -0700409 {Opt_grpquota, "grpquota"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 {Opt_ignore, "noquota"},
Mark Bellon8fc27512005-09-06 15:16:54 -0700411 {Opt_quota, "quota"},
412 {Opt_usrquota, "usrquota"},
Martin J. Bligha686cd82007-10-16 23:30:46 -0700413 {Opt_reservation, "reservation"},
414 {Opt_noreservation, "noreservation"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 {Opt_err, NULL}
416};
417
Alexey Fisher2314b072009-11-19 19:12:51 +0100418static int parse_options(char *options, struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419{
Alexey Fisher2314b072009-11-19 19:12:51 +0100420 char *p;
421 struct ext2_sb_info *sbi = EXT2_SB(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 substring_t args[MAX_OPT_ARGS];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 int option;
424
425 if (!options)
426 return 1;
427
428 while ((p = strsep (&options, ",")) != NULL) {
429 int token;
430 if (!*p)
431 continue;
432
433 token = match_token(p, tokens, args);
434 switch (token) {
435 case Opt_bsd_df:
436 clear_opt (sbi->s_mount_opt, MINIX_DF);
437 break;
438 case Opt_minix_df:
439 set_opt (sbi->s_mount_opt, MINIX_DF);
440 break;
441 case Opt_grpid:
442 set_opt (sbi->s_mount_opt, GRPID);
443 break;
444 case Opt_nogrpid:
445 clear_opt (sbi->s_mount_opt, GRPID);
446 break;
447 case Opt_resuid:
448 if (match_int(&args[0], &option))
449 return 0;
450 sbi->s_resuid = option;
451 break;
452 case Opt_resgid:
453 if (match_int(&args[0], &option))
454 return 0;
455 sbi->s_resgid = option;
456 break;
457 case Opt_sb:
458 /* handled by get_sb_block() instead of here */
459 /* *sb_block = match_int(&args[0]); */
460 break;
461 case Opt_err_panic:
Vasily Averin5a2b4062006-10-11 01:21:50 -0700462 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
463 clear_opt (sbi->s_mount_opt, ERRORS_RO);
464 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 break;
466 case Opt_err_ro:
Vasily Averin5a2b4062006-10-11 01:21:50 -0700467 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
468 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
469 set_opt (sbi->s_mount_opt, ERRORS_RO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 break;
471 case Opt_err_cont:
Vasily Averin5a2b4062006-10-11 01:21:50 -0700472 clear_opt (sbi->s_mount_opt, ERRORS_RO);
473 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
474 set_opt (sbi->s_mount_opt, ERRORS_CONT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 break;
476 case Opt_nouid32:
477 set_opt (sbi->s_mount_opt, NO_UID32);
478 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 case Opt_nocheck:
480 clear_opt (sbi->s_mount_opt, CHECK);
481 break;
482 case Opt_debug:
483 set_opt (sbi->s_mount_opt, DEBUG);
484 break;
485 case Opt_oldalloc:
486 set_opt (sbi->s_mount_opt, OLDALLOC);
487 break;
488 case Opt_orlov:
489 clear_opt (sbi->s_mount_opt, OLDALLOC);
490 break;
491 case Opt_nobh:
492 set_opt (sbi->s_mount_opt, NOBH);
493 break;
494#ifdef CONFIG_EXT2_FS_XATTR
495 case Opt_user_xattr:
496 set_opt (sbi->s_mount_opt, XATTR_USER);
497 break;
498 case Opt_nouser_xattr:
499 clear_opt (sbi->s_mount_opt, XATTR_USER);
500 break;
501#else
502 case Opt_user_xattr:
503 case Opt_nouser_xattr:
Alexey Fisher2314b072009-11-19 19:12:51 +0100504 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
505 "not supported");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 break;
507#endif
508#ifdef CONFIG_EXT2_FS_POSIX_ACL
509 case Opt_acl:
510 set_opt(sbi->s_mount_opt, POSIX_ACL);
511 break;
512 case Opt_noacl:
513 clear_opt(sbi->s_mount_opt, POSIX_ACL);
514 break;
515#else
516 case Opt_acl:
517 case Opt_noacl:
Alexey Fisher2314b072009-11-19 19:12:51 +0100518 ext2_msg(sb, KERN_INFO,
519 "(no)acl options not supported");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 break;
521#endif
Carsten Otte6d791252005-06-23 22:05:26 -0700522 case Opt_xip:
523#ifdef CONFIG_EXT2_FS_XIP
524 set_opt (sbi->s_mount_opt, XIP);
525#else
Alexey Fisher2314b072009-11-19 19:12:51 +0100526 ext2_msg(sb, KERN_INFO, "xip option not supported");
Carsten Otte6d791252005-06-23 22:05:26 -0700527#endif
528 break;
Mark Bellon8fc27512005-09-06 15:16:54 -0700529
530#if defined(CONFIG_QUOTA)
531 case Opt_quota:
532 case Opt_usrquota:
533 set_opt(sbi->s_mount_opt, USRQUOTA);
534 break;
535
536 case Opt_grpquota:
537 set_opt(sbi->s_mount_opt, GRPQUOTA);
538 break;
539#else
540 case Opt_quota:
541 case Opt_usrquota:
542 case Opt_grpquota:
Alexey Fisher2314b072009-11-19 19:12:51 +0100543 ext2_msg(sb, KERN_INFO,
544 "quota operations not supported");
Mark Bellon8fc27512005-09-06 15:16:54 -0700545 break;
546#endif
547
Martin J. Bligha686cd82007-10-16 23:30:46 -0700548 case Opt_reservation:
549 set_opt(sbi->s_mount_opt, RESERVATION);
Alexey Fisher2314b072009-11-19 19:12:51 +0100550 ext2_msg(sb, KERN_INFO, "reservations ON");
Martin J. Bligha686cd82007-10-16 23:30:46 -0700551 break;
552 case Opt_noreservation:
553 clear_opt(sbi->s_mount_opt, RESERVATION);
Alexey Fisher2314b072009-11-19 19:12:51 +0100554 ext2_msg(sb, KERN_INFO, "reservations OFF");
Martin J. Bligha686cd82007-10-16 23:30:46 -0700555 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 case Opt_ignore:
557 break;
558 default:
559 return 0;
560 }
561 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 return 1;
563}
564
565static int ext2_setup_super (struct super_block * sb,
566 struct ext2_super_block * es,
567 int read_only)
568{
569 int res = 0;
570 struct ext2_sb_info *sbi = EXT2_SB(sb);
571
572 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100573 ext2_msg(sb, KERN_ERR,
574 "error: revision level too high, "
575 "forcing read-only mode");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 res = MS_RDONLY;
577 }
578 if (read_only)
579 return res;
580 if (!(sbi->s_mount_state & EXT2_VALID_FS))
Alexey Fisher2314b072009-11-19 19:12:51 +0100581 ext2_msg(sb, KERN_WARNING,
582 "warning: mounting unchecked fs, "
583 "running e2fsck is recommended");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
Alexey Fisher2314b072009-11-19 19:12:51 +0100585 ext2_msg(sb, KERN_WARNING,
586 "warning: mounting fs with errors, "
587 "running e2fsck is recommended");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
589 le16_to_cpu(es->s_mnt_count) >=
590 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
Alexey Fisher2314b072009-11-19 19:12:51 +0100591 ext2_msg(sb, KERN_WARNING,
592 "warning: maximal mount count reached, "
593 "running e2fsck is recommended");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 else if (le32_to_cpu(es->s_checkinterval) &&
Alexey Fisher2314b072009-11-19 19:12:51 +0100595 (le32_to_cpu(es->s_lastcheck) +
596 le32_to_cpu(es->s_checkinterval) <= get_seconds()))
597 ext2_msg(sb, KERN_WARNING,
598 "warning: checktime reached, "
599 "running e2fsck is recommended");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 if (!le16_to_cpu(es->s_max_mnt_count))
601 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
Marcin Slusarzfba4d392008-04-28 02:15:59 -0700602 le16_add_cpu(&es->s_mnt_count, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 if (test_opt (sb, DEBUG))
Alexey Fisher2314b072009-11-19 19:12:51 +0100604 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
605 "bpg=%lu, ipg=%lu, mo=%04lx]",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
607 sbi->s_frag_size,
608 sbi->s_groups_count,
609 EXT2_BLOCKS_PER_GROUP(sb),
610 EXT2_INODES_PER_GROUP(sb),
611 sbi->s_mount_opt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 return res;
613}
614
Akinobu Mita197cd65a2008-02-06 01:40:16 -0800615static int ext2_check_descriptors(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616{
617 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 struct ext2_sb_info *sbi = EXT2_SB(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619
620 ext2_debug ("Checking group descriptors");
621
Akinobu Mita197cd65a2008-02-06 01:40:16 -0800622 for (i = 0; i < sbi->s_groups_count; i++) {
623 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
Akinobu Mita24097d12008-04-28 02:16:01 -0700624 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
625 ext2_fsblk_t last_block;
Akinobu Mita197cd65a2008-02-06 01:40:16 -0800626
Eric Sandeen41f04d82006-09-27 01:49:30 -0700627 if (i == sbi->s_groups_count - 1)
628 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
629 else
630 last_block = first_block +
631 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
632
Eric Sandeen41f04d82006-09-27 01:49:30 -0700633 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
634 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 {
636 ext2_error (sb, "ext2_check_descriptors",
637 "Block bitmap for group %d"
638 " not in group (block %lu)!",
639 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
640 return 0;
641 }
Eric Sandeen41f04d82006-09-27 01:49:30 -0700642 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
643 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 {
645 ext2_error (sb, "ext2_check_descriptors",
646 "Inode bitmap for group %d"
647 " not in group (block %lu)!",
648 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
649 return 0;
650 }
Eric Sandeen41f04d82006-09-27 01:49:30 -0700651 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
Eric Sandeen780dcdb2007-07-26 10:41:11 -0700652 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
Eric Sandeen41f04d82006-09-27 01:49:30 -0700653 last_block)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 {
655 ext2_error (sb, "ext2_check_descriptors",
656 "Inode table for group %d"
657 " not in group (block %lu)!",
658 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
659 return 0;
660 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 }
662 return 1;
663}
664
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665/*
666 * Maximal file size. There is a direct, and {,double-,triple-}indirect
667 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
668 * We need to be 1 filesystem block less than the 2^32 sector limit.
669 */
670static loff_t ext2_max_size(int bits)
671{
672 loff_t res = EXT2_NDIR_BLOCKS;
Aneesh Kumar K.V902be4c2008-01-28 23:58:26 -0500673 int meta_blocks;
674 loff_t upper_limit;
675
676 /* This is calculated to be the largest file size for a
677 * dense, file such that the total number of
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678 * sectors in the file, including data and all indirect blocks,
Aneesh Kumar K.V902be4c2008-01-28 23:58:26 -0500679 * does not exceed 2^32 -1
680 * __u32 i_blocks representing the total number of
681 * 512 bytes blocks of the file
682 */
683 upper_limit = (1LL << 32) - 1;
684
685 /* total blocks in file system block size */
686 upper_limit >>= (bits - 9);
687
688
689 /* indirect blocks */
690 meta_blocks = 1;
691 /* double indirect blocks */
692 meta_blocks += 1 + (1LL << (bits-2));
693 /* tripple indirect blocks */
694 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
695
696 upper_limit -= meta_blocks;
697 upper_limit <<= bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698
699 res += 1LL << (bits-2);
700 res += 1LL << (2*(bits-2));
701 res += 1LL << (3*(bits-2));
702 res <<= bits;
703 if (res > upper_limit)
704 res = upper_limit;
Aneesh Kumar K.V902be4c2008-01-28 23:58:26 -0500705
706 if (res > MAX_LFS_FILESIZE)
707 res = MAX_LFS_FILESIZE;
708
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 return res;
710}
711
712static unsigned long descriptor_loc(struct super_block *sb,
713 unsigned long logic_sb_block,
714 int nr)
715{
716 struct ext2_sb_info *sbi = EXT2_SB(sb);
Akinobu Mita24097d12008-04-28 02:16:01 -0700717 unsigned long bg, first_meta_bg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 int has_super = 0;
719
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
721
722 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
723 nr < first_meta_bg)
724 return (logic_sb_block + nr + 1);
725 bg = sbi->s_desc_per_block * nr;
726 if (ext2_bg_has_super(sb, bg))
727 has_super = 1;
Akinobu Mita24097d12008-04-28 02:16:01 -0700728
729 return ext2_group_first_block_no(sb, bg) + has_super;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730}
731
732static int ext2_fill_super(struct super_block *sb, void *data, int silent)
733{
734 struct buffer_head * bh;
735 struct ext2_sb_info * sbi;
736 struct ext2_super_block * es;
737 struct inode *root;
738 unsigned long block;
739 unsigned long sb_block = get_sb_block(&data);
740 unsigned long logic_sb_block;
741 unsigned long offset = 0;
742 unsigned long def_mount_opts;
David Howells52fcf702008-02-07 00:15:35 -0800743 long ret = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 int blocksize = BLOCK_SIZE;
745 int db_count;
746 int i, j;
747 __le32 features;
Peter Zijlstra833f4072007-10-16 23:25:45 -0700748 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749
Jan Blunckdb719222010-08-15 22:51:10 +0200750 err = -ENOMEM;
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -0700751 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 if (!sbi)
Jan Blunckdb719222010-08-15 22:51:10 +0200753 goto failed_unlock;
Pekka J Enberg18a82eb2009-01-07 18:07:19 -0800754
755 sbi->s_blockgroup_lock =
756 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
757 if (!sbi->s_blockgroup_lock) {
758 kfree(sbi);
Jan Blunckdb719222010-08-15 22:51:10 +0200759 goto failed_unlock;
Pekka J Enberg18a82eb2009-01-07 18:07:19 -0800760 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 sb->s_fs_info = sbi;
Miklos Szeredi93d44cb2007-10-16 23:26:26 -0700762 sbi->s_sb_block = sb_block;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763
Jan Blunckc15271f2010-04-14 14:38:38 +0200764 spin_lock_init(&sbi->s_lock);
765
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 /*
767 * See what the current blocksize for the device is, and
768 * use that as the blocksize. Otherwise (or if the blocksize
769 * is smaller than the default) use the default.
770 * This is important for devices that have a hardware
771 * sectorsize that is larger than the default.
772 */
773 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
774 if (!blocksize) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100775 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 goto failed_sbi;
777 }
778
779 /*
780 * If the superblock doesn't start on a hardware sector boundary,
781 * calculate the offset.
782 */
783 if (blocksize != BLOCK_SIZE) {
784 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
785 offset = (sb_block*BLOCK_SIZE) % blocksize;
786 } else {
787 logic_sb_block = sb_block;
788 }
789
790 if (!(bh = sb_bread(sb, logic_sb_block))) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100791 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 goto failed_sbi;
793 }
794 /*
795 * Note: s_es must be initialized as soon as possible because
796 * some ext2 macro-instructions depend on its value
797 */
798 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
799 sbi->s_es = es;
800 sb->s_magic = le16_to_cpu(es->s_magic);
801
802 if (sb->s_magic != EXT2_SUPER_MAGIC)
803 goto cantfind_ext2;
804
805 /* Set defaults before we parse the mount options */
806 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
807 if (def_mount_opts & EXT2_DEFM_DEBUG)
808 set_opt(sbi->s_mount_opt, DEBUG);
809 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
810 set_opt(sbi->s_mount_opt, GRPID);
811 if (def_mount_opts & EXT2_DEFM_UID16)
812 set_opt(sbi->s_mount_opt, NO_UID32);
Hugh Dickins2e7842b2007-02-10 01:46:13 -0800813#ifdef CONFIG_EXT2_FS_XATTR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
815 set_opt(sbi->s_mount_opt, XATTR_USER);
Hugh Dickins2e7842b2007-02-10 01:46:13 -0800816#endif
817#ifdef CONFIG_EXT2_FS_POSIX_ACL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 if (def_mount_opts & EXT2_DEFM_ACL)
819 set_opt(sbi->s_mount_opt, POSIX_ACL);
Hugh Dickins2e7842b2007-02-10 01:46:13 -0800820#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821
822 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
823 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
Aneesh Kumar K.V14e11e12008-02-06 01:36:17 -0800824 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
Vasily Averin5a2b4062006-10-11 01:21:50 -0700825 set_opt(sbi->s_mount_opt, ERRORS_CONT);
Aneesh Kumar K.V14e11e12008-02-06 01:36:17 -0800826 else
827 set_opt(sbi->s_mount_opt, ERRORS_RO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828
829 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
830 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
831
Martin J. Bligha686cd82007-10-16 23:30:46 -0700832 set_opt(sbi->s_mount_opt, RESERVATION);
833
Alexey Fisher2314b072009-11-19 19:12:51 +0100834 if (!parse_options((char *) data, sb))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 goto failed_mount;
836
837 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
838 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
839 MS_POSIXACL : 0);
840
Carsten Otte6d791252005-06-23 22:05:26 -0700841 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
842 EXT2_MOUNT_XIP if not */
843
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
845 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
846 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
847 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
Alexey Fisher2314b072009-11-19 19:12:51 +0100848 ext2_msg(sb, KERN_WARNING,
849 "warning: feature flags set on rev 0 fs, "
850 "running e2fsck is recommended");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 /*
852 * Check feature flags regardless of the revision level, since we
853 * previously didn't change the revision level when setting the flags,
854 * so there is a chance incompat flags are set on a rev 0 filesystem.
855 */
856 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
857 if (features) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100858 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
859 "unsupported optional features (%x)",
860 le32_to_cpu(features));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 goto failed_mount;
862 }
863 if (!(sb->s_flags & MS_RDONLY) &&
864 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
Alexey Fisher2314b072009-11-19 19:12:51 +0100865 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
866 "unsupported optional features (%x)",
867 le32_to_cpu(features));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 goto failed_mount;
869 }
870
871 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
872
Nick Piggina8e3eff2008-02-06 01:37:42 -0800873 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) {
Carsten Otte6d791252005-06-23 22:05:26 -0700874 if (!silent)
Alexey Fisher2314b072009-11-19 19:12:51 +0100875 ext2_msg(sb, KERN_ERR,
876 "error: unsupported blocksize for xip");
Carsten Otte6d791252005-06-23 22:05:26 -0700877 goto failed_mount;
878 }
879
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 /* If the blocksize doesn't match, re-read the thing.. */
881 if (sb->s_blocksize != blocksize) {
882 brelse(bh);
883
884 if (!sb_set_blocksize(sb, blocksize)) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100885 ext2_msg(sb, KERN_ERR, "error: blocksize is too small");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 goto failed_sbi;
887 }
888
889 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
890 offset = (sb_block*BLOCK_SIZE) % blocksize;
891 bh = sb_bread(sb, logic_sb_block);
892 if(!bh) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100893 ext2_msg(sb, KERN_ERR, "error: couldn't read"
894 "superblock on 2nd try");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 goto failed_sbi;
896 }
897 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
898 sbi->s_es = es;
899 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100900 ext2_msg(sb, KERN_ERR, "error: magic mismatch");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901 goto failed_mount;
902 }
903 }
904
905 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
906
907 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
908 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
909 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
910 } else {
911 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
912 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
913 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
vignesh babud8ea6cf2007-10-16 23:27:14 -0700914 !is_power_of_2(sbi->s_inode_size) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 (sbi->s_inode_size > blocksize)) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100916 ext2_msg(sb, KERN_ERR,
917 "error: unsupported inode size: %d",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 sbi->s_inode_size);
919 goto failed_mount;
920 }
921 }
922
923 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
924 le32_to_cpu(es->s_log_frag_size);
925 if (sbi->s_frag_size == 0)
926 goto cantfind_ext2;
927 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
928
929 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
930 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
931 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
932
933 if (EXT2_INODE_SIZE(sb) == 0)
934 goto cantfind_ext2;
935 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
Andries Brouwer607eb262006-08-27 01:23:43 -0700936 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700937 goto cantfind_ext2;
938 sbi->s_itb_per_group = sbi->s_inodes_per_group /
939 sbi->s_inodes_per_block;
940 sbi->s_desc_per_block = sb->s_blocksize /
941 sizeof (struct ext2_group_desc);
942 sbi->s_sbh = bh;
943 sbi->s_mount_state = le16_to_cpu(es->s_state);
944 sbi->s_addr_per_block_bits =
David Howellsf0d1b0b2006-12-08 02:37:49 -0800945 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946 sbi->s_desc_per_block_bits =
David Howellsf0d1b0b2006-12-08 02:37:49 -0800947 ilog2 (EXT2_DESC_PER_BLOCK(sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948
949 if (sb->s_magic != EXT2_SUPER_MAGIC)
950 goto cantfind_ext2;
951
952 if (sb->s_blocksize != bh->b_size) {
953 if (!silent)
Alexey Fisher2314b072009-11-19 19:12:51 +0100954 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 goto failed_mount;
956 }
957
958 if (sb->s_blocksize != sbi->s_frag_size) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100959 ext2_msg(sb, KERN_ERR,
960 "error: fragsize %lu != blocksize %lu"
961 "(not supported yet)",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962 sbi->s_frag_size, sb->s_blocksize);
963 goto failed_mount;
964 }
965
966 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100967 ext2_msg(sb, KERN_ERR,
968 "error: #blocks per group too big: %lu",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 sbi->s_blocks_per_group);
970 goto failed_mount;
971 }
972 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100973 ext2_msg(sb, KERN_ERR,
974 "error: #fragments per group too big: %lu",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 sbi->s_frags_per_group);
976 goto failed_mount;
977 }
978 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100979 ext2_msg(sb, KERN_ERR,
980 "error: #inodes per group too big: %lu",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 sbi->s_inodes_per_group);
982 goto failed_mount;
983 }
984
985 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
986 goto cantfind_ext2;
Eric Sandeen41f04d82006-09-27 01:49:30 -0700987 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
988 le32_to_cpu(es->s_first_data_block) - 1)
989 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
991 EXT2_DESC_PER_BLOCK(sb);
992 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
993 if (sbi->s_group_desc == NULL) {
Alexey Fisher2314b072009-11-19 19:12:51 +0100994 ext2_msg(sb, KERN_ERR, "error: not enough memory");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 goto failed_mount;
996 }
Pekka J Enberg18a82eb2009-01-07 18:07:19 -0800997 bgl_lock_init(sbi->s_blockgroup_lock);
Yoann Padioleaudd00cc42007-07-19 01:49:03 -0700998 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700999 if (!sbi->s_debts) {
Alexey Fisher2314b072009-11-19 19:12:51 +01001000 ext2_msg(sb, KERN_ERR, "error: not enough memory");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001 goto failed_mount_group_desc;
1002 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003 for (i = 0; i < db_count; i++) {
1004 block = descriptor_loc(sb, logic_sb_block, i);
1005 sbi->s_group_desc[i] = sb_bread(sb, block);
1006 if (!sbi->s_group_desc[i]) {
1007 for (j = 0; j < i; j++)
1008 brelse (sbi->s_group_desc[j]);
Alexey Fisher2314b072009-11-19 19:12:51 +01001009 ext2_msg(sb, KERN_ERR,
1010 "error: unable to read group descriptors");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 goto failed_mount_group_desc;
1012 }
1013 }
1014 if (!ext2_check_descriptors (sb)) {
Alexey Fisher2314b072009-11-19 19:12:51 +01001015 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 goto failed_mount2;
1017 }
1018 sbi->s_gdb_count = db_count;
1019 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1020 spin_lock_init(&sbi->s_next_gen_lock);
Mingming Cao0216bfc2006-06-23 02:05:41 -07001021
Martin J. Bligha686cd82007-10-16 23:30:46 -07001022 /* per fileystem reservation list head & lock */
1023 spin_lock_init(&sbi->s_rsv_window_lock);
1024 sbi->s_rsv_window_root = RB_ROOT;
1025 /*
1026 * Add a single, static dummy reservation to the start of the
1027 * reservation window list --- it gives us a placeholder for
1028 * append-at-start-of-list which makes the allocation logic
1029 * _much_ simpler.
1030 */
1031 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1032 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1033 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1034 sbi->s_rsv_window_head.rsv_goal_size = 0;
1035 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1036
Peter Zijlstra833f4072007-10-16 23:25:45 -07001037 err = percpu_counter_init(&sbi->s_freeblocks_counter,
Mingming Cao0216bfc2006-06-23 02:05:41 -07001038 ext2_count_free_blocks(sb));
Peter Zijlstra833f4072007-10-16 23:25:45 -07001039 if (!err) {
1040 err = percpu_counter_init(&sbi->s_freeinodes_counter,
Mingming Cao0216bfc2006-06-23 02:05:41 -07001041 ext2_count_free_inodes(sb));
Peter Zijlstra833f4072007-10-16 23:25:45 -07001042 }
1043 if (!err) {
1044 err = percpu_counter_init(&sbi->s_dirs_counter,
Mingming Cao0216bfc2006-06-23 02:05:41 -07001045 ext2_count_dirs(sb));
Peter Zijlstra833f4072007-10-16 23:25:45 -07001046 }
1047 if (err) {
Alexey Fisher2314b072009-11-19 19:12:51 +01001048 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
Peter Zijlstra833f4072007-10-16 23:25:45 -07001049 goto failed_mount3;
1050 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 /*
1052 * set up enough so that it can read an inode
1053 */
1054 sb->s_op = &ext2_sops;
1055 sb->s_export_op = &ext2_export_ops;
1056 sb->s_xattr = ext2_xattr_handlers;
Christoph Hellwig123e9ca2010-05-19 07:16:44 -04001057
1058#ifdef CONFIG_QUOTA
1059 sb->dq_op = &dquot_operations;
Christoph Hellwig287a8092010-05-19 07:16:45 -04001060 sb->s_qcop = &dquot_quotactl_ops;
Christoph Hellwig123e9ca2010-05-19 07:16:44 -04001061#endif
1062
David Howells52fcf702008-02-07 00:15:35 -08001063 root = ext2_iget(sb, EXT2_ROOT_INO);
1064 if (IS_ERR(root)) {
1065 ret = PTR_ERR(root);
1066 goto failed_mount3;
1067 }
1068 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1069 iput(root);
Alexey Fisher2314b072009-11-19 19:12:51 +01001070 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
David Howells52fcf702008-02-07 00:15:35 -08001071 goto failed_mount3;
1072 }
1073
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074 sb->s_root = d_alloc_root(root);
1075 if (!sb->s_root) {
1076 iput(root);
Alexey Fisher2314b072009-11-19 19:12:51 +01001077 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
David Howells52fcf702008-02-07 00:15:35 -08001078 ret = -ENOMEM;
Mingming Cao0216bfc2006-06-23 02:05:41 -07001079 goto failed_mount3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080 }
1081 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
Alexey Fisher2314b072009-11-19 19:12:51 +01001082 ext2_msg(sb, KERN_WARNING,
1083 "warning: mounting ext3 filesystem as ext2");
Jan Blunck4c96a682010-04-14 14:38:37 +02001084 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY))
1085 sb->s_flags |= MS_RDONLY;
1086 ext2_write_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 return 0;
1088
1089cantfind_ext2:
1090 if (!silent)
Alexey Fisher2314b072009-11-19 19:12:51 +01001091 ext2_msg(sb, KERN_ERR,
1092 "error: can't find an ext2 filesystem on dev %s.",
1093 sb->s_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001094 goto failed_mount;
Mingming Cao0216bfc2006-06-23 02:05:41 -07001095failed_mount3:
1096 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1097 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1098 percpu_counter_destroy(&sbi->s_dirs_counter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099failed_mount2:
1100 for (i = 0; i < db_count; i++)
1101 brelse(sbi->s_group_desc[i]);
1102failed_mount_group_desc:
1103 kfree(sbi->s_group_desc);
1104 kfree(sbi->s_debts);
1105failed_mount:
1106 brelse(bh);
1107failed_sbi:
1108 sb->s_fs_info = NULL;
Manish Katiyar0f7ee7c2009-05-17 23:52:51 -04001109 kfree(sbi->s_blockgroup_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 kfree(sbi);
Jan Blunckdb719222010-08-15 22:51:10 +02001111failed_unlock:
David Howells52fcf702008-02-07 00:15:35 -08001112 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113}
1114
Theodore Ts'o7bf0dc92009-12-15 16:46:48 -08001115static void ext2_clear_super_error(struct super_block *sb)
1116{
1117 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1118
1119 if (buffer_write_io_error(sbh)) {
1120 /*
1121 * Oh, dear. A previous attempt to write the
1122 * superblock failed. This could happen because the
1123 * USB device was yanked out. Or it could happen to
1124 * be a transient write error and maybe the block will
1125 * be remapped. Nothing we can do but to retry the
1126 * write and hope for the best.
1127 */
Jan Blunck2b8120e2010-04-14 14:38:33 +02001128 ext2_msg(sb, KERN_ERR,
1129 "previous I/O error to superblock detected\n");
Theodore Ts'o7bf0dc92009-12-15 16:46:48 -08001130 clear_buffer_write_io_error(sbh);
1131 set_buffer_uptodate(sbh);
1132 }
1133}
1134
Jan Blunckee6921e2010-04-14 14:38:36 +02001135static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1136 int wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137{
Theodore Ts'o7bf0dc92009-12-15 16:46:48 -08001138 ext2_clear_super_error(sb);
Jan Blunckc15271f2010-04-14 14:38:38 +02001139 spin_lock(&EXT2_SB(sb)->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1141 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1142 es->s_wtime = cpu_to_le32(get_seconds());
Jan Blunckc15271f2010-04-14 14:38:38 +02001143 /* unlock before we do IO */
1144 spin_unlock(&EXT2_SB(sb)->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
Jan Blunckee6921e2010-04-14 14:38:36 +02001146 if (wait)
1147 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148 sb->s_dirt = 0;
1149}
1150
1151/*
1152 * In the second extended file system, it is not necessary to
1153 * write the super block since we use a mapping of the
1154 * disk super block in a buffer.
1155 *
1156 * However, this function is still used to set the fs valid
1157 * flags to 0. We need to set this flag to 0 since the fs
1158 * may have been checked while mounted and e2fsck may have
1159 * set s_state to EXT2_VALID_FS after some corrections.
1160 */
Christoph Hellwig40f31dd2009-06-08 10:04:17 +02001161static int ext2_sync_fs(struct super_block *sb, int wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162{
Jan Blunckc15271f2010-04-14 14:38:38 +02001163 struct ext2_sb_info *sbi = EXT2_SB(sb);
Christoph Hellwig40f31dd2009-06-08 10:04:17 +02001164 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165
Jan Blunckc15271f2010-04-14 14:38:38 +02001166 spin_lock(&sbi->s_lock);
Christoph Hellwig40f31dd2009-06-08 10:04:17 +02001167 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1168 ext2_debug("setting valid to 0\n");
1169 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170 }
Jan Blunckc15271f2010-04-14 14:38:38 +02001171 spin_unlock(&sbi->s_lock);
Jan Blunckee6921e2010-04-14 14:38:36 +02001172 ext2_sync_super(sb, es, wait);
Christoph Hellwig40f31dd2009-06-08 10:04:17 +02001173 return 0;
1174}
1175
1176
1177void ext2_write_super(struct super_block *sb)
1178{
1179 if (!(sb->s_flags & MS_RDONLY))
1180 ext2_sync_fs(sb, 1);
1181 else
1182 sb->s_dirt = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183}
1184
1185static int ext2_remount (struct super_block * sb, int * flags, char * data)
1186{
1187 struct ext2_sb_info * sbi = EXT2_SB(sb);
1188 struct ext2_super_block * es;
Carsten Otte6d791252005-06-23 22:05:26 -07001189 unsigned long old_mount_opt = sbi->s_mount_opt;
Jan Kara50a52232005-07-12 13:58:29 -07001190 struct ext2_mount_options old_opts;
1191 unsigned long old_sb_flags;
1192 int err;
1193
Jan Blunckc15271f2010-04-14 14:38:38 +02001194 spin_lock(&sbi->s_lock);
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001195
Jan Kara50a52232005-07-12 13:58:29 -07001196 /* Store the old options */
1197 old_sb_flags = sb->s_flags;
1198 old_opts.s_mount_opt = sbi->s_mount_opt;
1199 old_opts.s_resuid = sbi->s_resuid;
1200 old_opts.s_resgid = sbi->s_resgid;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001201
1202 /*
1203 * Allow the "check" option to be passed as a remount option.
1204 */
Alexey Fisher2314b072009-11-19 19:12:51 +01001205 if (!parse_options(data, sb)) {
Jan Kara50a52232005-07-12 13:58:29 -07001206 err = -EINVAL;
1207 goto restore_opts;
1208 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001209
1210 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1211 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1212
Carsten Otte266f5aa2007-06-23 17:16:46 -07001213 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
1214 EXT2_MOUNT_XIP if not */
1215
1216 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) {
Alexey Fisher2314b072009-11-19 19:12:51 +01001217 ext2_msg(sb, KERN_WARNING,
1218 "warning: unsupported blocksize for xip");
Andrew Mortonddc80bd2007-06-27 14:10:08 -07001219 err = -EINVAL;
Carsten Otte266f5aa2007-06-23 17:16:46 -07001220 goto restore_opts;
1221 }
1222
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223 es = sbi->s_es;
Al Viro8e3b9a02010-10-24 09:45:22 -04001224 if ((sbi->s_mount_opt ^ old_mount_opt) & EXT2_MOUNT_XIP) {
Alexey Fisher2314b072009-11-19 19:12:51 +01001225 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1226 "xip flag with busy inodes while remounting");
Carsten Otte0e4a9b52009-02-11 13:04:37 -08001227 sbi->s_mount_opt &= ~EXT2_MOUNT_XIP;
1228 sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP;
1229 }
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001230 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
Jan Blunckc15271f2010-04-14 14:38:38 +02001231 spin_unlock(&sbi->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232 return 0;
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001233 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234 if (*flags & MS_RDONLY) {
1235 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001236 !(sbi->s_mount_state & EXT2_VALID_FS)) {
Jan Blunckc15271f2010-04-14 14:38:38 +02001237 spin_unlock(&sbi->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 return 0;
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001239 }
Christoph Hellwigc79d9672010-05-19 07:16:40 -04001240
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 /*
1242 * OK, we are remounting a valid rw partition rdonly, so set
1243 * the rdonly flag and then mark the partition as valid again.
1244 */
1245 es->s_state = cpu_to_le16(sbi->s_mount_state);
1246 es->s_mtime = cpu_to_le32(get_seconds());
Jan Blunckc15271f2010-04-14 14:38:38 +02001247 spin_unlock(&sbi->s_lock);
Christoph Hellwigc79d9672010-05-19 07:16:40 -04001248
Christoph Hellwig0f0dd622010-05-19 07:16:41 -04001249 err = dquot_suspend(sb, -1);
1250 if (err < 0) {
Christoph Hellwigc79d9672010-05-19 07:16:40 -04001251 spin_lock(&sbi->s_lock);
1252 goto restore_opts;
1253 }
1254
Jan Blunck4c96a682010-04-14 14:38:37 +02001255 ext2_sync_super(sb, es, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256 } else {
1257 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1258 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1259 if (ret) {
Alexey Fisher2314b072009-11-19 19:12:51 +01001260 ext2_msg(sb, KERN_WARNING,
1261 "warning: couldn't remount RDWR because of "
1262 "unsupported optional features (%x).",
1263 le32_to_cpu(ret));
Jan Kara50a52232005-07-12 13:58:29 -07001264 err = -EROFS;
1265 goto restore_opts;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266 }
1267 /*
1268 * Mounting a RDONLY partition read-write, so reread and
1269 * store the current valid flag. (It may have been changed
1270 * by e2fsck since we originally mounted the partition.)
1271 */
1272 sbi->s_mount_state = le16_to_cpu(es->s_state);
1273 if (!ext2_setup_super (sb, es, 0))
1274 sb->s_flags &= ~MS_RDONLY;
Jan Blunckc15271f2010-04-14 14:38:38 +02001275 spin_unlock(&sbi->s_lock);
Christoph Hellwigc79d9672010-05-19 07:16:40 -04001276
Jan Blunck4c96a682010-04-14 14:38:37 +02001277 ext2_write_super(sb);
Christoph Hellwigc79d9672010-05-19 07:16:40 -04001278
Christoph Hellwig0f0dd622010-05-19 07:16:41 -04001279 dquot_resume(sb, -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280 }
Christoph Hellwigc79d9672010-05-19 07:16:40 -04001281
Linus Torvalds1da177e2005-04-16 15:20:36 -07001282 return 0;
Jan Kara50a52232005-07-12 13:58:29 -07001283restore_opts:
1284 sbi->s_mount_opt = old_opts.s_mount_opt;
1285 sbi->s_resuid = old_opts.s_resuid;
1286 sbi->s_resgid = old_opts.s_resgid;
1287 sb->s_flags = old_sb_flags;
Jan Blunckc15271f2010-04-14 14:38:38 +02001288 spin_unlock(&sbi->s_lock);
Jan Kara50a52232005-07-12 13:58:29 -07001289 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290}
1291
David Howells726c3342006-06-23 02:02:58 -07001292static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293{
David Howells726c3342006-06-23 02:02:58 -07001294 struct super_block *sb = dentry->d_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 struct ext2_sb_info *sbi = EXT2_SB(sb);
Pekka Enberge4fca012006-12-06 20:35:27 -08001296 struct ext2_super_block *es = sbi->s_es;
Pekka Enberge4fca012006-12-06 20:35:27 -08001297 u64 fsid;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298
Jan Blunckc15271f2010-04-14 14:38:38 +02001299 spin_lock(&sbi->s_lock);
1300
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301 if (test_opt (sb, MINIX_DF))
Badari Pulavarty22352192007-07-15 23:41:58 -07001302 sbi->s_overhead_last = 0;
1303 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1304 unsigned long i, overhead = 0;
1305 smp_rmb();
1306
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307 /*
Badari Pulavarty22352192007-07-15 23:41:58 -07001308 * Compute the overhead (FS structures). This is constant
1309 * for a given filesystem unless the number of block groups
1310 * changes so we cache the previous value until it does.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001311 */
1312
1313 /*
1314 * All of the blocks before first_data_block are
1315 * overhead
1316 */
Pekka Enberge4fca012006-12-06 20:35:27 -08001317 overhead = le32_to_cpu(es->s_first_data_block);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318
1319 /*
1320 * Add the overhead attributed to the superblock and
1321 * block group descriptors. If the sparse superblocks
1322 * feature is turned on, then not all groups have this.
1323 */
1324 for (i = 0; i < sbi->s_groups_count; i++)
1325 overhead += ext2_bg_has_super(sb, i) +
1326 ext2_bg_num_gdb(sb, i);
1327
1328 /*
1329 * Every block group has an inode bitmap, a block
1330 * bitmap, and an inode table.
1331 */
1332 overhead += (sbi->s_groups_count *
1333 (2 + sbi->s_itb_per_group));
Badari Pulavarty22352192007-07-15 23:41:58 -07001334 sbi->s_overhead_last = overhead;
1335 smp_wmb();
1336 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337 }
1338
1339 buf->f_type = EXT2_SUPER_MAGIC;
1340 buf->f_bsize = sb->s_blocksize;
Badari Pulavarty22352192007-07-15 23:41:58 -07001341 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342 buf->f_bfree = ext2_count_free_blocks(sb);
Badari Pulavarty22352192007-07-15 23:41:58 -07001343 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
Pekka Enberge4fca012006-12-06 20:35:27 -08001344 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1345 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 buf->f_bavail = 0;
Pekka Enberge4fca012006-12-06 20:35:27 -08001347 buf->f_files = le32_to_cpu(es->s_inodes_count);
1348 buf->f_ffree = ext2_count_free_inodes(sb);
Badari Pulavarty22352192007-07-15 23:41:58 -07001349 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350 buf->f_namelen = EXT2_NAME_LEN;
Pekka Enberge4fca012006-12-06 20:35:27 -08001351 fsid = le64_to_cpup((void *)es->s_uuid) ^
1352 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1353 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1354 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
Jan Blunckc15271f2010-04-14 14:38:38 +02001355 spin_unlock(&sbi->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356 return 0;
1357}
1358
Al Viro152a0832010-07-25 00:46:55 +04001359static struct dentry *ext2_mount(struct file_system_type *fs_type,
1360 int flags, const char *dev_name, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361{
Al Viro152a0832010-07-25 00:46:55 +04001362 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363}
1364
1365#ifdef CONFIG_QUOTA
1366
1367/* Read data from quotafile - avoid pagecache and such because we cannot afford
1368 * acquiring the locks... As quota files are never truncated and quota code
1369 * itself serializes the operations (and noone else should touch the files)
1370 * we don't have to be afraid of races */
1371static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1372 size_t len, loff_t off)
1373{
1374 struct inode *inode = sb_dqopt(sb)->files[type];
1375 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1376 int err = 0;
1377 int offset = off & (sb->s_blocksize - 1);
1378 int tocopy;
1379 size_t toread;
1380 struct buffer_head tmp_bh;
1381 struct buffer_head *bh;
1382 loff_t i_size = i_size_read(inode);
1383
1384 if (off > i_size)
1385 return 0;
1386 if (off+len > i_size)
1387 len = i_size-off;
1388 toread = len;
1389 while (toread > 0) {
1390 tocopy = sb->s_blocksize - offset < toread ?
1391 sb->s_blocksize - offset : toread;
1392
1393 tmp_bh.b_state = 0;
Manish Katiyarc16831b2009-02-12 21:57:04 +01001394 tmp_bh.b_size = sb->s_blocksize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001395 err = ext2_get_block(inode, blk, &tmp_bh, 0);
Martin J. Bligha686cd82007-10-16 23:30:46 -07001396 if (err < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397 return err;
1398 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1399 memset(data, 0, tocopy);
1400 else {
1401 bh = sb_bread(sb, tmp_bh.b_blocknr);
1402 if (!bh)
1403 return -EIO;
1404 memcpy(data, bh->b_data+offset, tocopy);
1405 brelse(bh);
1406 }
1407 offset = 0;
1408 toread -= tocopy;
1409 data += tocopy;
1410 blk++;
1411 }
1412 return len;
1413}
1414
1415/* Write to quotafile */
1416static ssize_t ext2_quota_write(struct super_block *sb, int type,
1417 const char *data, size_t len, loff_t off)
1418{
1419 struct inode *inode = sb_dqopt(sb)->files[type];
1420 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1421 int err = 0;
1422 int offset = off & (sb->s_blocksize - 1);
1423 int tocopy;
1424 size_t towrite = len;
1425 struct buffer_head tmp_bh;
1426 struct buffer_head *bh;
1427
Arjan van de Ven5c81a412006-07-03 00:25:20 -07001428 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429 while (towrite > 0) {
1430 tocopy = sb->s_blocksize - offset < towrite ?
1431 sb->s_blocksize - offset : towrite;
1432
1433 tmp_bh.b_state = 0;
1434 err = ext2_get_block(inode, blk, &tmp_bh, 1);
Martin J. Bligha686cd82007-10-16 23:30:46 -07001435 if (err < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001436 goto out;
1437 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1438 bh = sb_bread(sb, tmp_bh.b_blocknr);
1439 else
1440 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1441 if (!bh) {
1442 err = -EIO;
1443 goto out;
1444 }
1445 lock_buffer(bh);
1446 memcpy(bh->b_data+offset, data, tocopy);
1447 flush_dcache_page(bh->b_page);
1448 set_buffer_uptodate(bh);
1449 mark_buffer_dirty(bh);
1450 unlock_buffer(bh);
1451 brelse(bh);
1452 offset = 0;
1453 towrite -= tocopy;
1454 data += tocopy;
1455 blk++;
1456 }
1457out:
Dan Carpentera069e9c2009-04-09 18:07:10 +02001458 if (len == towrite) {
1459 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001460 return err;
Dan Carpentera069e9c2009-04-09 18:07:10 +02001461 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462 if (inode->i_size < off+len-towrite)
1463 i_size_write(inode, off+len-towrite);
1464 inode->i_version++;
1465 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1466 mark_inode_dirty(inode);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001467 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468 return len - towrite;
1469}
1470
1471#endif
1472
1473static struct file_system_type ext2_fs_type = {
1474 .owner = THIS_MODULE,
1475 .name = "ext2",
Al Viro152a0832010-07-25 00:46:55 +04001476 .mount = ext2_mount,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001477 .kill_sb = kill_block_super,
1478 .fs_flags = FS_REQUIRES_DEV,
1479};
1480
1481static int __init init_ext2_fs(void)
1482{
1483 int err = init_ext2_xattr();
1484 if (err)
1485 return err;
1486 err = init_inodecache();
1487 if (err)
1488 goto out1;
1489 err = register_filesystem(&ext2_fs_type);
1490 if (err)
1491 goto out;
1492 return 0;
1493out:
1494 destroy_inodecache();
1495out1:
1496 exit_ext2_xattr();
1497 return err;
1498}
1499
1500static void __exit exit_ext2_fs(void)
1501{
1502 unregister_filesystem(&ext2_fs_type);
1503 destroy_inodecache();
1504 exit_ext2_xattr();
1505}
1506
1507module_init(init_ext2_fs)
1508module_exit(exit_ext2_fs)