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[net-next-2.6.git] / fs / ext2 / super.c
CommitLineData
1da177e4
LT		 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/config.h>
20#include <linux/module.h>
21#include <linux/string.h>
8fc2751b 22#include <linux/fs.h>
1da177e4
LT		 23#include <linux/slab.h>
24#include <linux/init.h>
25#include <linux/blkdev.h>
26#include <linux/parser.h>
27#include <linux/random.h>
28#include <linux/buffer_head.h>
29#include <linux/smp_lock.h>
30#include <linux/vfs.h>
8fc2751b
MB		 31#include <linux/seq_file.h>
32#include <linux/mount.h>
1da177e4
LT		 33#include <asm/uaccess.h>
34#include "ext2.h"
35#include "xattr.h"
36#include "acl.h"
6d79125b 37#include "xip.h"
1da177e4
LT		 38
39static void ext2_sync_super(struct super_block *sb,
40 struct ext2_super_block *es);
41static int ext2_remount (struct super_block * sb, int * flags, char * data);
726c3342 42static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
1da177e4
LT		 43
44void ext2_error (struct super_block * sb, const char * function,
45 const char * fmt, ...)
46{
47 va_list args;
48 struct ext2_sb_info *sbi = EXT2_SB(sb);
49 struct ext2_super_block *es = sbi->s_es;
50
51 if (!(sb->s_flags & MS_RDONLY)) {
52 sbi->s_mount_state |= EXT2_ERROR_FS;
53 es->s_state =
54 cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS);
55 ext2_sync_super(sb, es);
56 }
57
58 va_start(args, fmt);
59 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function);
60 vprintk(fmt, args);
61 printk("\n");
62 va_end(args);
63
64 if (test_opt(sb, ERRORS_PANIC))
65 panic("EXT2-fs panic from previous error\n");
66 if (test_opt(sb, ERRORS_RO)) {
67 printk("Remounting filesystem read-only\n");
68 sb->s_flags |= MS_RDONLY;
69 }
70}
71
72void ext2_warning (struct super_block * sb, const char * function,
73 const char * fmt, ...)
74{
75 va_list args;
76
77 va_start(args, fmt);
78 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ",
79 sb->s_id, function);
80 vprintk(fmt, args);
81 printk("\n");
82 va_end(args);
83}
84
85void ext2_update_dynamic_rev(struct super_block *sb)
86{
87 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
88
89 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
90 return;
91
92 ext2_warning(sb, __FUNCTION__,
93 "updating to rev %d because of new feature flag, "
94 "running e2fsck is recommended",
95 EXT2_DYNAMIC_REV);
96
97 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
98 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
99 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
100 /* leave es->s_feature_*compat flags alone */
101 /* es->s_uuid will be set by e2fsck if empty */
102
103 /*
104 * The rest of the superblock fields should be zero, and if not it
105 * means they are likely already in use, so leave them alone. We
106 * can leave it up to e2fsck to clean up any inconsistencies there.
107 */
108}
109
110static void ext2_put_super (struct super_block * sb)
111{
112 int db_count;
113 int i;
114 struct ext2_sb_info *sbi = EXT2_SB(sb);
115
116 ext2_xattr_put_super(sb);
117 if (!(sb->s_flags & MS_RDONLY)) {
118 struct ext2_super_block *es = sbi->s_es;
119
120 es->s_state = cpu_to_le16(sbi->s_mount_state);
121 ext2_sync_super(sb, es);
122 }
123 db_count = sbi->s_gdb_count;
124 for (i = 0; i < db_count; i++)
125 if (sbi->s_group_desc[i])
126 brelse (sbi->s_group_desc[i]);
127 kfree(sbi->s_group_desc);
128 kfree(sbi->s_debts);
129 percpu_counter_destroy(&sbi->s_freeblocks_counter);
130 percpu_counter_destroy(&sbi->s_freeinodes_counter);
131 percpu_counter_destroy(&sbi->s_dirs_counter);
132 brelse (sbi->s_sbh);
133 sb->s_fs_info = NULL;
134 kfree(sbi);
135
136 return;
137}
138
139static kmem_cache_t * ext2_inode_cachep;
140
141static struct inode *ext2_alloc_inode(struct super_block *sb)
142{
143 struct ext2_inode_info *ei;
144 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, SLAB_KERNEL);
145 if (!ei)
146 return NULL;
147#ifdef CONFIG_EXT2_FS_POSIX_ACL
148 ei->i_acl = EXT2_ACL_NOT_CACHED;
149 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
150#endif
151 ei->vfs_inode.i_version = 1;
152 return &ei->vfs_inode;
153}
154
155static void ext2_destroy_inode(struct inode *inode)
156{
157 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
158}
159
160static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
161{
162 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
163
164 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
165 SLAB_CTOR_CONSTRUCTOR) {
166 rwlock_init(&ei->i_meta_lock);
167#ifdef CONFIG_EXT2_FS_XATTR
168 init_rwsem(&ei->xattr_sem);
169#endif
170 inode_init_once(&ei->vfs_inode);
171 }
172}
173
174static int init_inodecache(void)
175{
176 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
177 sizeof(struct ext2_inode_info),
fffb60f9
PJ		 178 0, (SLAB_RECLAIM_ACCOUNT|
179 SLAB_MEM_SPREAD),
1da177e4
LT		 180 init_once, NULL);
181 if (ext2_inode_cachep == NULL)
182 return -ENOMEM;
183 return 0;
184}
185
186static void destroy_inodecache(void)
187{
188 if (kmem_cache_destroy(ext2_inode_cachep))
189 printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n");
190}
191
192static void ext2_clear_inode(struct inode *inode)
193{
194#ifdef CONFIG_EXT2_FS_POSIX_ACL
195 struct ext2_inode_info *ei = EXT2_I(inode);
196
197 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
198 posix_acl_release(ei->i_acl);
199 ei->i_acl = EXT2_ACL_NOT_CACHED;
200 }
201 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
202 posix_acl_release(ei->i_default_acl);
203 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
204 }
205#endif
1da177e4
LT		 206}
207
8fc2751b
MB		 208static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
209{
210 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
211
212 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
213 seq_puts(seq, ",grpid");
8fc2751b
MB		 214
215#if defined(CONFIG_QUOTA)
216 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
217 seq_puts(seq, ",usrquota");
218
219 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
220 seq_puts(seq, ",grpquota");
221#endif
222
83541796
CO		 223#if defined(CONFIG_EXT2_FS_XIP)
224 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
225 seq_puts(seq, ",xip");
226#endif
227
8fc2751b
MB		 228 return 0;
229}
230
1da177e4
LT		 231#ifdef CONFIG_QUOTA
232static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
233static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
234#endif
235
236static struct super_operations ext2_sops = {
237 .alloc_inode = ext2_alloc_inode,
238 .destroy_inode = ext2_destroy_inode,
239 .read_inode = ext2_read_inode,
240 .write_inode = ext2_write_inode,
e072c6f2 241 .put_inode = ext2_put_inode,
1da177e4
LT		 242 .delete_inode = ext2_delete_inode,
243 .put_super = ext2_put_super,
244 .write_super = ext2_write_super,
245 .statfs = ext2_statfs,
246 .remount_fs = ext2_remount,
247 .clear_inode = ext2_clear_inode,
8fc2751b 248 .show_options = ext2_show_options,
1da177e4
LT		 249#ifdef CONFIG_QUOTA
250 .quota_read = ext2_quota_read,
251 .quota_write = ext2_quota_write,
252#endif
253};
254
255/* Yes, most of these are left as NULL!!
256 * A NULL value implies the default, which works with ext2-like file
257 * systems, but can be improved upon.
258 * Currently only get_parent is required.
259 */
1da177e4
LT		 260static struct export_operations ext2_export_ops = {
261 .get_parent = ext2_get_parent,
262};
263
264static unsigned long get_sb_block(void **data)
265{
266 unsigned long sb_block;
267 char *options = (char *) *data;
268
269 if (!options || strncmp(options, "sb=", 3) != 0)
270 return 1; /* Default location */
271 options += 3;
272 sb_block = simple_strtoul(options, &options, 0);
273 if (*options && *options != ',') {
274 printk("EXT2-fs: Invalid sb specification: %s\n",
275 (char *) *data);
276 return 1;
277 }
278 if (*options == ',')
279 options++;
280 *data = (void *) options;
281 return sb_block;
282}
283
284enum {
285 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
8fc2751b 286 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
2860b733 287 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
8fc2751b
MB		 288 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
289 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
290 Opt_usrquota, Opt_grpquota
1da177e4
LT		 291};
292
293static match_table_t tokens = {
294 {Opt_bsd_df, "bsddf"},
295 {Opt_minix_df, "minixdf"},
296 {Opt_grpid, "grpid"},
297 {Opt_grpid, "bsdgroups"},
298 {Opt_nogrpid, "nogrpid"},
299 {Opt_nogrpid, "sysvgroups"},
300 {Opt_resgid, "resgid=%u"},
301 {Opt_resuid, "resuid=%u"},
302 {Opt_sb, "sb=%u"},
303 {Opt_err_cont, "errors=continue"},
304 {Opt_err_panic, "errors=panic"},
305 {Opt_err_ro, "errors=remount-ro"},
306 {Opt_nouid32, "nouid32"},
307 {Opt_nocheck, "check=none"},
308 {Opt_nocheck, "nocheck"},
1da177e4
LT		 309 {Opt_debug, "debug"},
310 {Opt_oldalloc, "oldalloc"},
311 {Opt_orlov, "orlov"},
312 {Opt_nobh, "nobh"},
313 {Opt_user_xattr, "user_xattr"},
314 {Opt_nouser_xattr, "nouser_xattr"},
315 {Opt_acl, "acl"},
316 {Opt_noacl, "noacl"},
6d79125b 317 {Opt_xip, "xip"},
8fc2751b 318 {Opt_grpquota, "grpquota"},
1da177e4 319 {Opt_ignore, "noquota"},
8fc2751b
MB		 320 {Opt_quota, "quota"},
321 {Opt_usrquota, "usrquota"},
1da177e4
LT		 322 {Opt_err, NULL}
323};
324
325static int parse_options (char * options,
326 struct ext2_sb_info *sbi)
327{
328 char * p;
329 substring_t args[MAX_OPT_ARGS];
330 unsigned long kind = EXT2_MOUNT_ERRORS_CONT;
331 int option;
332
333 if (!options)
334 return 1;
335
336 while ((p = strsep (&options, ",")) != NULL) {
337 int token;
338 if (!*p)
339 continue;
340
341 token = match_token(p, tokens, args);
342 switch (token) {
343 case Opt_bsd_df:
344 clear_opt (sbi->s_mount_opt, MINIX_DF);
345 break;
346 case Opt_minix_df:
347 set_opt (sbi->s_mount_opt, MINIX_DF);
348 break;
349 case Opt_grpid:
350 set_opt (sbi->s_mount_opt, GRPID);
351 break;
352 case Opt_nogrpid:
353 clear_opt (sbi->s_mount_opt, GRPID);
354 break;
355 case Opt_resuid:
356 if (match_int(&args[0], &option))
357 return 0;
358 sbi->s_resuid = option;
359 break;
360 case Opt_resgid:
361 if (match_int(&args[0], &option))
362 return 0;
363 sbi->s_resgid = option;
364 break;
365 case Opt_sb:
366 /* handled by get_sb_block() instead of here */
367 /* *sb_block = match_int(&args[0]); */
368 break;
369 case Opt_err_panic:
370 kind = EXT2_MOUNT_ERRORS_PANIC;
371 break;
372 case Opt_err_ro:
373 kind = EXT2_MOUNT_ERRORS_RO;
374 break;
375 case Opt_err_cont:
376 kind = EXT2_MOUNT_ERRORS_CONT;
377 break;
378 case Opt_nouid32:
379 set_opt (sbi->s_mount_opt, NO_UID32);
380 break;
1da177e4
LT		 381 case Opt_nocheck:
382 clear_opt (sbi->s_mount_opt, CHECK);
383 break;
384 case Opt_debug:
385 set_opt (sbi->s_mount_opt, DEBUG);
386 break;
387 case Opt_oldalloc:
388 set_opt (sbi->s_mount_opt, OLDALLOC);
389 break;
390 case Opt_orlov:
391 clear_opt (sbi->s_mount_opt, OLDALLOC);
392 break;
393 case Opt_nobh:
394 set_opt (sbi->s_mount_opt, NOBH);
395 break;
396#ifdef CONFIG_EXT2_FS_XATTR
397 case Opt_user_xattr:
398 set_opt (sbi->s_mount_opt, XATTR_USER);
399 break;
400 case Opt_nouser_xattr:
401 clear_opt (sbi->s_mount_opt, XATTR_USER);
402 break;
403#else
404 case Opt_user_xattr:
405 case Opt_nouser_xattr:
406 printk("EXT2 (no)user_xattr options not supported\n");
407 break;
408#endif
409#ifdef CONFIG_EXT2_FS_POSIX_ACL
410 case Opt_acl:
411 set_opt(sbi->s_mount_opt, POSIX_ACL);
412 break;
413 case Opt_noacl:
414 clear_opt(sbi->s_mount_opt, POSIX_ACL);
415 break;
416#else
417 case Opt_acl:
418 case Opt_noacl:
419 printk("EXT2 (no)acl options not supported\n");
420 break;
421#endif
6d79125b
CO		 422 case Opt_xip:
423#ifdef CONFIG_EXT2_FS_XIP
424 set_opt (sbi->s_mount_opt, XIP);
425#else
426 printk("EXT2 xip option not supported\n");
427#endif
428 break;
8fc2751b
MB		 429
430#if defined(CONFIG_QUOTA)
431 case Opt_quota:
432 case Opt_usrquota:
433 set_opt(sbi->s_mount_opt, USRQUOTA);
434 break;
435
436 case Opt_grpquota:
437 set_opt(sbi->s_mount_opt, GRPQUOTA);
438 break;
439#else
440 case Opt_quota:
441 case Opt_usrquota:
442 case Opt_grpquota:
443 printk(KERN_ERR
444 "EXT2-fs: quota operations not supported.\n");
445
446 break;
447#endif
448
1da177e4
LT		 449 case Opt_ignore:
450 break;
451 default:
452 return 0;
453 }
454 }
455 sbi->s_mount_opt |= kind;
456 return 1;
457}
458
459static int ext2_setup_super (struct super_block * sb,
460 struct ext2_super_block * es,
461 int read_only)
462{
463 int res = 0;
464 struct ext2_sb_info *sbi = EXT2_SB(sb);
465
466 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
467 printk ("EXT2-fs warning: revision level too high, "
468 "forcing read-only mode\n");
469 res = MS_RDONLY;
470 }
471 if (read_only)
472 return res;
473 if (!(sbi->s_mount_state & EXT2_VALID_FS))
474 printk ("EXT2-fs warning: mounting unchecked fs, "
475 "running e2fsck is recommended\n");
476 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
477 printk ("EXT2-fs warning: mounting fs with errors, "
478 "running e2fsck is recommended\n");
479 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
480 le16_to_cpu(es->s_mnt_count) >=
481 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
482 printk ("EXT2-fs warning: maximal mount count reached, "
483 "running e2fsck is recommended\n");
484 else if (le32_to_cpu(es->s_checkinterval) &&
485 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
486 printk ("EXT2-fs warning: checktime reached, "
487 "running e2fsck is recommended\n");
488 if (!le16_to_cpu(es->s_max_mnt_count))
489 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
490 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
491 ext2_write_super(sb);
492 if (test_opt (sb, DEBUG))
493 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
494 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
495 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
496 sbi->s_frag_size,
497 sbi->s_groups_count,
498 EXT2_BLOCKS_PER_GROUP(sb),
499 EXT2_INODES_PER_GROUP(sb),
500 sbi->s_mount_opt);
1da177e4
LT		 501 return res;
502}
503
504static int ext2_check_descriptors (struct super_block * sb)
505{
506 int i;
507 int desc_block = 0;
508 struct ext2_sb_info *sbi = EXT2_SB(sb);
509 unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block);
510 struct ext2_group_desc * gdp = NULL;
511
512 ext2_debug ("Checking group descriptors");
513
514 for (i = 0; i < sbi->s_groups_count; i++)
515 {
516 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
517 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
518 if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
519 le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
520 {
521 ext2_error (sb, "ext2_check_descriptors",
522 "Block bitmap for group %d"
523 " not in group (block %lu)!",
524 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
525 return 0;
526 }
527 if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
528 le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
529 {
530 ext2_error (sb, "ext2_check_descriptors",
531 "Inode bitmap for group %d"
532 " not in group (block %lu)!",
533 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
534 return 0;
535 }
536 if (le32_to_cpu(gdp->bg_inode_table) < block ||
537 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >=
538 block + EXT2_BLOCKS_PER_GROUP(sb))
539 {
540 ext2_error (sb, "ext2_check_descriptors",
541 "Inode table for group %d"
542 " not in group (block %lu)!",
543 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
544 return 0;
545 }
546 block += EXT2_BLOCKS_PER_GROUP(sb);
547 gdp++;
548 }
549 return 1;
550}
551
552#define log2(n) ffz(~(n))
553
554/*
555 * Maximal file size. There is a direct, and {,double-,triple-}indirect
556 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
557 * We need to be 1 filesystem block less than the 2^32 sector limit.
558 */
559static loff_t ext2_max_size(int bits)
560{
561 loff_t res = EXT2_NDIR_BLOCKS;
562 /* This constant is calculated to be the largest file size for a
563 * dense, 4k-blocksize file such that the total number of
564 * sectors in the file, including data and all indirect blocks,
565 * does not exceed 2^32. */
566 const loff_t upper_limit = 0x1ff7fffd000LL;
567
568 res += 1LL << (bits-2);
569 res += 1LL << (2*(bits-2));
570 res += 1LL << (3*(bits-2));
571 res <<= bits;
572 if (res > upper_limit)
573 res = upper_limit;
574 return res;
575}
576
577static unsigned long descriptor_loc(struct super_block *sb,
578 unsigned long logic_sb_block,
579 int nr)
580{
581 struct ext2_sb_info *sbi = EXT2_SB(sb);
582 unsigned long bg, first_data_block, first_meta_bg;
583 int has_super = 0;
584
585 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
586 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
587
588 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
589 nr < first_meta_bg)
590 return (logic_sb_block + nr + 1);
591 bg = sbi->s_desc_per_block * nr;
592 if (ext2_bg_has_super(sb, bg))
593 has_super = 1;
594 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
595}
596
597static int ext2_fill_super(struct super_block *sb, void *data, int silent)
598{
599 struct buffer_head * bh;
600 struct ext2_sb_info * sbi;
601 struct ext2_super_block * es;
602 struct inode *root;
603 unsigned long block;
604 unsigned long sb_block = get_sb_block(&data);
605 unsigned long logic_sb_block;
606 unsigned long offset = 0;
607 unsigned long def_mount_opts;
608 int blocksize = BLOCK_SIZE;
609 int db_count;
610 int i, j;
611 __le32 features;
612
613 sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
614 if (!sbi)
615 return -ENOMEM;
616 sb->s_fs_info = sbi;
617 memset(sbi, 0, sizeof(*sbi));
618
619 /*
620 * See what the current blocksize for the device is, and
621 * use that as the blocksize. Otherwise (or if the blocksize
622 * is smaller than the default) use the default.
623 * This is important for devices that have a hardware
624 * sectorsize that is larger than the default.
625 */
626 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
627 if (!blocksize) {
628 printk ("EXT2-fs: unable to set blocksize\n");
629 goto failed_sbi;
630 }
631
632 /*
633 * If the superblock doesn't start on a hardware sector boundary,
634 * calculate the offset.
635 */
636 if (blocksize != BLOCK_SIZE) {
637 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
638 offset = (sb_block*BLOCK_SIZE) % blocksize;
639 } else {
640 logic_sb_block = sb_block;
641 }
642
643 if (!(bh = sb_bread(sb, logic_sb_block))) {
644 printk ("EXT2-fs: unable to read superblock\n");
645 goto failed_sbi;
646 }
647 /*
648 * Note: s_es must be initialized as soon as possible because
649 * some ext2 macro-instructions depend on its value
650 */
651 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
652 sbi->s_es = es;
653 sb->s_magic = le16_to_cpu(es->s_magic);
654
655 if (sb->s_magic != EXT2_SUPER_MAGIC)
656 goto cantfind_ext2;
657
658 /* Set defaults before we parse the mount options */
659 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
660 if (def_mount_opts & EXT2_DEFM_DEBUG)
661 set_opt(sbi->s_mount_opt, DEBUG);
662 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
663 set_opt(sbi->s_mount_opt, GRPID);
664 if (def_mount_opts & EXT2_DEFM_UID16)
665 set_opt(sbi->s_mount_opt, NO_UID32);
666 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
667 set_opt(sbi->s_mount_opt, XATTR_USER);
668 if (def_mount_opts & EXT2_DEFM_ACL)
669 set_opt(sbi->s_mount_opt, POSIX_ACL);
670
671 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
672 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
673 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
674 set_opt(sbi->s_mount_opt, ERRORS_RO);
675
676 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
677 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
678
679 if (!parse_options ((char *) data, sbi))
680 goto failed_mount;
681
682 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
683 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
684 MS_POSIXACL : 0);
685
6d79125b
CO		 686 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
687 EXT2_MOUNT_XIP if not */
688
1da177e4
LT		 689 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
690 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
691 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
692 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
693 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
694 "running e2fsck is recommended\n");
695 /*
696 * Check feature flags regardless of the revision level, since we
697 * previously didn't change the revision level when setting the flags,
698 * so there is a chance incompat flags are set on a rev 0 filesystem.
699 */
700 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
701 if (features) {
702 printk("EXT2-fs: %s: couldn't mount because of "
703 "unsupported optional features (%x).\n",
704 sb->s_id, le32_to_cpu(features));
705 goto failed_mount;
706 }
707 if (!(sb->s_flags & MS_RDONLY) &&
708 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
709 printk("EXT2-fs: %s: couldn't mount RDWR because of "
710 "unsupported optional features (%x).\n",
711 sb->s_id, le32_to_cpu(features));
712 goto failed_mount;
713 }
714
715 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
716
6d79125b
CO		 717 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
718 (sb->s_blocksize != blocksize))) {
719 if (!silent)
720 printk("XIP: Unsupported blocksize\n");
721 goto failed_mount;
722 }
723
1da177e4
LT		 724 /* If the blocksize doesn't match, re-read the thing.. */
725 if (sb->s_blocksize != blocksize) {
726 brelse(bh);
727
728 if (!sb_set_blocksize(sb, blocksize)) {
729 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
730 goto failed_sbi;
731 }
732
733 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
734 offset = (sb_block*BLOCK_SIZE) % blocksize;
735 bh = sb_bread(sb, logic_sb_block);
736 if(!bh) {
737 printk("EXT2-fs: Couldn't read superblock on "
738 "2nd try.\n");
739 goto failed_sbi;
740 }
741 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
742 sbi->s_es = es;
743 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
744 printk ("EXT2-fs: Magic mismatch, very weird !\n");
745 goto failed_mount;
746 }
747 }
748
749 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
750
751 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
752 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
753 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
754 } else {
755 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
756 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
757 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
758 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
759 (sbi->s_inode_size > blocksize)) {
760 printk ("EXT2-fs: unsupported inode size: %d\n",
761 sbi->s_inode_size);
762 goto failed_mount;
763 }
764 }
765
766 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
767 le32_to_cpu(es->s_log_frag_size);
768 if (sbi->s_frag_size == 0)
769 goto cantfind_ext2;
770 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
771
772 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
773 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
774 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
775
776 if (EXT2_INODE_SIZE(sb) == 0)
777 goto cantfind_ext2;
778 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
779 if (sbi->s_inodes_per_block == 0)
780 goto cantfind_ext2;
781 sbi->s_itb_per_group = sbi->s_inodes_per_group /
782 sbi->s_inodes_per_block;
783 sbi->s_desc_per_block = sb->s_blocksize /
784 sizeof (struct ext2_group_desc);
785 sbi->s_sbh = bh;
786 sbi->s_mount_state = le16_to_cpu(es->s_state);
787 sbi->s_addr_per_block_bits =
788 log2 (EXT2_ADDR_PER_BLOCK(sb));
789 sbi->s_desc_per_block_bits =
790 log2 (EXT2_DESC_PER_BLOCK(sb));
791
792 if (sb->s_magic != EXT2_SUPER_MAGIC)
793 goto cantfind_ext2;
794
795 if (sb->s_blocksize != bh->b_size) {
796 if (!silent)
797 printk ("VFS: Unsupported blocksize on dev "
798 "%s.\n", sb->s_id);
799 goto failed_mount;
800 }
801
802 if (sb->s_blocksize != sbi->s_frag_size) {
803 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
804 sbi->s_frag_size, sb->s_blocksize);
805 goto failed_mount;
806 }
807
808 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
809 printk ("EXT2-fs: #blocks per group too big: %lu\n",
810 sbi->s_blocks_per_group);
811 goto failed_mount;
812 }
813 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
814 printk ("EXT2-fs: #fragments per group too big: %lu\n",
815 sbi->s_frags_per_group);
816 goto failed_mount;
817 }
818 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
819 printk ("EXT2-fs: #inodes per group too big: %lu\n",
820 sbi->s_inodes_per_group);
821 goto failed_mount;
822 }
823
824 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
825 goto cantfind_ext2;
826 sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
827 le32_to_cpu(es->s_first_data_block) +
828 EXT2_BLOCKS_PER_GROUP(sb) - 1) /
829 EXT2_BLOCKS_PER_GROUP(sb);
830 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
831 EXT2_DESC_PER_BLOCK(sb);
832 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
833 if (sbi->s_group_desc == NULL) {
834 printk ("EXT2-fs: not enough memory\n");
835 goto failed_mount;
836 }
837 percpu_counter_init(&sbi->s_freeblocks_counter);
838 percpu_counter_init(&sbi->s_freeinodes_counter);
839 percpu_counter_init(&sbi->s_dirs_counter);
840 bgl_lock_init(&sbi->s_blockgroup_lock);
841 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
842 GFP_KERNEL);
843 if (!sbi->s_debts) {
844 printk ("EXT2-fs: not enough memory\n");
845 goto failed_mount_group_desc;
846 }
847 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
848 for (i = 0; i < db_count; i++) {
849 block = descriptor_loc(sb, logic_sb_block, i);
850 sbi->s_group_desc[i] = sb_bread(sb, block);
851 if (!sbi->s_group_desc[i]) {
852 for (j = 0; j < i; j++)
853 brelse (sbi->s_group_desc[j]);
854 printk ("EXT2-fs: unable to read group descriptors\n");
855 goto failed_mount_group_desc;
856 }
857 }
858 if (!ext2_check_descriptors (sb)) {
859 printk ("EXT2-fs: group descriptors corrupted!\n");
860 db_count = i;
861 goto failed_mount2;
862 }
863 sbi->s_gdb_count = db_count;
864 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
865 spin_lock_init(&sbi->s_next_gen_lock);
866 /*
867 * set up enough so that it can read an inode
868 */
869 sb->s_op = &ext2_sops;
870 sb->s_export_op = &ext2_export_ops;
871 sb->s_xattr = ext2_xattr_handlers;
872 root = iget(sb, EXT2_ROOT_INO);
873 sb->s_root = d_alloc_root(root);
874 if (!sb->s_root) {
875 iput(root);
876 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
877 goto failed_mount2;
878 }
879 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
880 dput(sb->s_root);
881 sb->s_root = NULL;
882 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
883 goto failed_mount2;
884 }
885 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
886 ext2_warning(sb, __FUNCTION__,
ec63f22d 887 "mounting ext3 filesystem as ext2");
1da177e4
LT		 888 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
889 percpu_counter_mod(&sbi->s_freeblocks_counter,
890 ext2_count_free_blocks(sb));
891 percpu_counter_mod(&sbi->s_freeinodes_counter,
892 ext2_count_free_inodes(sb));
893 percpu_counter_mod(&sbi->s_dirs_counter,
894 ext2_count_dirs(sb));
895 return 0;
896
897cantfind_ext2:
898 if (!silent)
899 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
900 sb->s_id);
901 goto failed_mount;
902
903failed_mount2:
904 for (i = 0; i < db_count; i++)
905 brelse(sbi->s_group_desc[i]);
906failed_mount_group_desc:
907 kfree(sbi->s_group_desc);
908 kfree(sbi->s_debts);
909failed_mount:
910 brelse(bh);
911failed_sbi:
912 sb->s_fs_info = NULL;
913 kfree(sbi);
914 return -EINVAL;
915}
916
917static void ext2_commit_super (struct super_block * sb,
918 struct ext2_super_block * es)
919{
920 es->s_wtime = cpu_to_le32(get_seconds());
921 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
922 sb->s_dirt = 0;
923}
924
925static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
926{
927 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
928 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
929 es->s_wtime = cpu_to_le32(get_seconds());
930 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
931 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
932 sb->s_dirt = 0;
933}
934
935/*
936 * In the second extended file system, it is not necessary to
937 * write the super block since we use a mapping of the
938 * disk super block in a buffer.
939 *
940 * However, this function is still used to set the fs valid
941 * flags to 0. We need to set this flag to 0 since the fs
942 * may have been checked while mounted and e2fsck may have
943 * set s_state to EXT2_VALID_FS after some corrections.
944 */
945
946void ext2_write_super (struct super_block * sb)
947{
948 struct ext2_super_block * es;
949 lock_kernel();
950 if (!(sb->s_flags & MS_RDONLY)) {
951 es = EXT2_SB(sb)->s_es;
952
953 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
954 ext2_debug ("setting valid to 0\n");
955 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
956 ~EXT2_VALID_FS);
957 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
958 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
959 es->s_mtime = cpu_to_le32(get_seconds());
960 ext2_sync_super(sb, es);
961 } else
962 ext2_commit_super (sb, es);
963 }
964 sb->s_dirt = 0;
965 unlock_kernel();
966}
967
968static int ext2_remount (struct super_block * sb, int * flags, char * data)
969{
970 struct ext2_sb_info * sbi = EXT2_SB(sb);
971 struct ext2_super_block * es;
6d79125b 972 unsigned long old_mount_opt = sbi->s_mount_opt;
50a52234
JK		 973 struct ext2_mount_options old_opts;
974 unsigned long old_sb_flags;
975 int err;
976
977 /* Store the old options */
978 old_sb_flags = sb->s_flags;
979 old_opts.s_mount_opt = sbi->s_mount_opt;
980 old_opts.s_resuid = sbi->s_resuid;
981 old_opts.s_resgid = sbi->s_resgid;
1da177e4
LT		 982
983 /*
984 * Allow the "check" option to be passed as a remount option.
985 */
50a52234
JK		 986 if (!parse_options (data, sbi)) {
987 err = -EINVAL;
988 goto restore_opts;
989 }
1da177e4
LT		 990
991 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
992 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
993
994 es = sbi->s_es;
6d79125b
CO		 995 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
996 (old_mount_opt & EXT2_MOUNT_XIP)) &&
997 invalidate_inodes(sb))
998 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
999 "xip remain in cache (no functional problem)");
1da177e4
LT		 1000 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1001 return 0;
1002 if (*flags & MS_RDONLY) {
1003 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1004 !(sbi->s_mount_state & EXT2_VALID_FS))
1005 return 0;
1006 /*
1007 * OK, we are remounting a valid rw partition rdonly, so set
1008 * the rdonly flag and then mark the partition as valid again.
1009 */
1010 es->s_state = cpu_to_le16(sbi->s_mount_state);
1011 es->s_mtime = cpu_to_le32(get_seconds());
1012 } else {
1013 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1014 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1015 if (ret) {
1016 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1017 "unsupported optional features (%x).\n",
1018 sb->s_id, le32_to_cpu(ret));
50a52234
JK		 1019 err = -EROFS;
1020 goto restore_opts;
1da177e4
LT		 1021 }
1022 /*
1023 * Mounting a RDONLY partition read-write, so reread and
1024 * store the current valid flag. (It may have been changed
1025 * by e2fsck since we originally mounted the partition.)
1026 */
1027 sbi->s_mount_state = le16_to_cpu(es->s_state);
1028 if (!ext2_setup_super (sb, es, 0))
1029 sb->s_flags &= ~MS_RDONLY;
1030 }
1031 ext2_sync_super(sb, es);
1032 return 0;
50a52234
JK		 1033restore_opts:
1034 sbi->s_mount_opt = old_opts.s_mount_opt;
1035 sbi->s_resuid = old_opts.s_resuid;
1036 sbi->s_resgid = old_opts.s_resgid;
1037 sb->s_flags = old_sb_flags;
1038 return err;
1da177e4
LT		 1039}
1040
726c3342 1041static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1da177e4 1042{
726c3342 1043 struct super_block *sb = dentry->d_sb;
1da177e4
LT		 1044 struct ext2_sb_info *sbi = EXT2_SB(sb);
1045 unsigned long overhead;
1046 int i;
1047
1048 if (test_opt (sb, MINIX_DF))
1049 overhead = 0;
1050 else {
1051 /*
1052 * Compute the overhead (FS structures)
1053 */
1054
1055 /*
1056 * All of the blocks before first_data_block are
1057 * overhead
1058 */
1059 overhead = le32_to_cpu(sbi->s_es->s_first_data_block);
1060
1061 /*
1062 * Add the overhead attributed to the superblock and
1063 * block group descriptors. If the sparse superblocks
1064 * feature is turned on, then not all groups have this.
1065 */
1066 for (i = 0; i < sbi->s_groups_count; i++)
1067 overhead += ext2_bg_has_super(sb, i) +
1068 ext2_bg_num_gdb(sb, i);
1069
1070 /*
1071 * Every block group has an inode bitmap, a block
1072 * bitmap, and an inode table.
1073 */
1074 overhead += (sbi->s_groups_count *
1075 (2 + sbi->s_itb_per_group));
1076 }
1077
1078 buf->f_type = EXT2_SUPER_MAGIC;
1079 buf->f_bsize = sb->s_blocksize;
1080 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead;
1081 buf->f_bfree = ext2_count_free_blocks(sb);
1082 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count);
1083 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count))
1084 buf->f_bavail = 0;
1085 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count);
1086 buf->f_ffree = ext2_count_free_inodes (sb);
1087 buf->f_namelen = EXT2_NAME_LEN;
1088 return 0;
1089}
1090
454e2398
DH		 1091static int ext2_get_sb(struct file_system_type *fs_type,
1092 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1da177e4 1093{
454e2398 1094 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1da177e4
LT		 1095}
1096
1097#ifdef CONFIG_QUOTA
1098
1099/* Read data from quotafile - avoid pagecache and such because we cannot afford
1100 * acquiring the locks... As quota files are never truncated and quota code
1101 * itself serializes the operations (and noone else should touch the files)
1102 * we don't have to be afraid of races */
1103static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1104 size_t len, loff_t off)
1105{
1106 struct inode *inode = sb_dqopt(sb)->files[type];
1107 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1108 int err = 0;
1109 int offset = off & (sb->s_blocksize - 1);
1110 int tocopy;
1111 size_t toread;
1112 struct buffer_head tmp_bh;
1113 struct buffer_head *bh;
1114 loff_t i_size = i_size_read(inode);
1115
1116 if (off > i_size)
1117 return 0;
1118 if (off+len > i_size)
1119 len = i_size-off;
1120 toread = len;
1121 while (toread > 0) {
1122 tocopy = sb->s_blocksize - offset < toread ?
1123 sb->s_blocksize - offset : toread;
1124
1125 tmp_bh.b_state = 0;
1126 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1127 if (err)
1128 return err;
1129 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1130 memset(data, 0, tocopy);
1131 else {
1132 bh = sb_bread(sb, tmp_bh.b_blocknr);
1133 if (!bh)
1134 return -EIO;
1135 memcpy(data, bh->b_data+offset, tocopy);
1136 brelse(bh);
1137 }
1138 offset = 0;
1139 toread -= tocopy;
1140 data += tocopy;
1141 blk++;
1142 }
1143 return len;
1144}
1145
1146/* Write to quotafile */
1147static ssize_t ext2_quota_write(struct super_block *sb, int type,
1148 const char *data, size_t len, loff_t off)
1149{
1150 struct inode *inode = sb_dqopt(sb)->files[type];
1151 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1152 int err = 0;
1153 int offset = off & (sb->s_blocksize - 1);
1154 int tocopy;
1155 size_t towrite = len;
1156 struct buffer_head tmp_bh;
1157 struct buffer_head *bh;
1158
1b1dcc1b 1159 mutex_lock(&inode->i_mutex);
1da177e4
LT		 1160 while (towrite > 0) {
1161 tocopy = sb->s_blocksize - offset < towrite ?
1162 sb->s_blocksize - offset : towrite;
1163
1164 tmp_bh.b_state = 0;
1165 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1166 if (err)
1167 goto out;
1168 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1169 bh = sb_bread(sb, tmp_bh.b_blocknr);
1170 else
1171 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1172 if (!bh) {
1173 err = -EIO;
1174 goto out;
1175 }
1176 lock_buffer(bh);
1177 memcpy(bh->b_data+offset, data, tocopy);
1178 flush_dcache_page(bh->b_page);
1179 set_buffer_uptodate(bh);
1180 mark_buffer_dirty(bh);
1181 unlock_buffer(bh);
1182 brelse(bh);
1183 offset = 0;
1184 towrite -= tocopy;
1185 data += tocopy;
1186 blk++;
1187 }
1188out:
1189 if (len == towrite)
1190 return err;
1191 if (inode->i_size < off+len-towrite)
1192 i_size_write(inode, off+len-towrite);
1193 inode->i_version++;
1194 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1195 mark_inode_dirty(inode);
1b1dcc1b 1196 mutex_unlock(&inode->i_mutex);
1da177e4
LT		 1197 return len - towrite;
1198}
1199
1200#endif
1201
1202static struct file_system_type ext2_fs_type = {
1203 .owner = THIS_MODULE,
1204 .name = "ext2",
1205 .get_sb = ext2_get_sb,
1206 .kill_sb = kill_block_super,
1207 .fs_flags = FS_REQUIRES_DEV,
1208};
1209
1210static int __init init_ext2_fs(void)
1211{
1212 int err = init_ext2_xattr();
1213 if (err)
1214 return err;
1215 err = init_inodecache();
1216 if (err)
1217 goto out1;
1218 err = register_filesystem(&ext2_fs_type);
1219 if (err)
1220 goto out;
1221 return 0;
1222out:
1223 destroy_inodecache();
1224out1:
1225 exit_ext2_xattr();
1226 return err;
1227}
1228
1229static void __exit exit_ext2_fs(void)
1230{
1231 unregister_filesystem(&ext2_fs_type);
1232 destroy_inodecache();
1233 exit_ext2_xattr();
1234}
1235
1236module_init(init_ext2_fs)
1237module_exit(exit_ext2_fs)
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