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[PATCH] Fix for minix crash
[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
1da177e4
LT		 19#include <linux/module.h>
20#include <linux/string.h>
8fc2751b 21#include <linux/fs.h>
1da177e4
LT		 22#include <linux/slab.h>
23#include <linux/init.h>
24#include <linux/blkdev.h>
25#include <linux/parser.h>
26#include <linux/random.h>
27#include <linux/buffer_head.h>
28#include <linux/smp_lock.h>
29#include <linux/vfs.h>
8fc2751b
MB		 30#include <linux/seq_file.h>
31#include <linux/mount.h>
1da177e4
LT		 32#include <asm/uaccess.h>
33#include "ext2.h"
34#include "xattr.h"
35#include "acl.h"
6d79125b 36#include "xip.h"
1da177e4
LT		 37
38static void ext2_sync_super(struct super_block *sb,
39 struct ext2_super_block *es);
40static int ext2_remount (struct super_block * sb, int * flags, char * data);
726c3342 41static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
1da177e4
LT		 42
43void ext2_error (struct super_block * sb, const char * function,
44 const char * fmt, ...)
45{
46 va_list args;
47 struct ext2_sb_info *sbi = EXT2_SB(sb);
48 struct ext2_super_block *es = sbi->s_es;
49
50 if (!(sb->s_flags & MS_RDONLY)) {
51 sbi->s_mount_state |= EXT2_ERROR_FS;
52 es->s_state =
53 cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS);
54 ext2_sync_super(sb, es);
55 }
56
57 va_start(args, fmt);
58 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function);
59 vprintk(fmt, args);
60 printk("\n");
61 va_end(args);
62
63 if (test_opt(sb, ERRORS_PANIC))
64 panic("EXT2-fs panic from previous error\n");
65 if (test_opt(sb, ERRORS_RO)) {
66 printk("Remounting filesystem read-only\n");
67 sb->s_flags |= MS_RDONLY;
68 }
69}
70
71void ext2_warning (struct super_block * sb, const char * function,
72 const char * fmt, ...)
73{
74 va_list args;
75
76 va_start(args, fmt);
77 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ",
78 sb->s_id, function);
79 vprintk(fmt, args);
80 printk("\n");
81 va_end(args);
82}
83
84void ext2_update_dynamic_rev(struct super_block *sb)
85{
86 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
87
88 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
89 return;
90
91 ext2_warning(sb, __FUNCTION__,
92 "updating to rev %d because of new feature flag, "
93 "running e2fsck is recommended",
94 EXT2_DYNAMIC_REV);
95
96 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
97 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
98 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
99 /* leave es->s_feature_*compat flags alone */
100 /* es->s_uuid will be set by e2fsck if empty */
101
102 /*
103 * The rest of the superblock fields should be zero, and if not it
104 * means they are likely already in use, so leave them alone. We
105 * can leave it up to e2fsck to clean up any inconsistencies there.
106 */
107}
108
109static void ext2_put_super (struct super_block * sb)
110{
111 int db_count;
112 int i;
113 struct ext2_sb_info *sbi = EXT2_SB(sb);
114
115 ext2_xattr_put_super(sb);
116 if (!(sb->s_flags & MS_RDONLY)) {
117 struct ext2_super_block *es = sbi->s_es;
118
119 es->s_state = cpu_to_le16(sbi->s_mount_state);
120 ext2_sync_super(sb, es);
121 }
122 db_count = sbi->s_gdb_count;
123 for (i = 0; i < db_count; i++)
124 if (sbi->s_group_desc[i])
125 brelse (sbi->s_group_desc[i]);
126 kfree(sbi->s_group_desc);
127 kfree(sbi->s_debts);
128 percpu_counter_destroy(&sbi->s_freeblocks_counter);
129 percpu_counter_destroy(&sbi->s_freeinodes_counter);
130 percpu_counter_destroy(&sbi->s_dirs_counter);
131 brelse (sbi->s_sbh);
132 sb->s_fs_info = NULL;
133 kfree(sbi);
134
135 return;
136}
137
138static kmem_cache_t * ext2_inode_cachep;
139
140static struct inode *ext2_alloc_inode(struct super_block *sb)
141{
142 struct ext2_inode_info *ei;
143 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, SLAB_KERNEL);
144 if (!ei)
145 return NULL;
146#ifdef CONFIG_EXT2_FS_POSIX_ACL
147 ei->i_acl = EXT2_ACL_NOT_CACHED;
148 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
149#endif
150 ei->vfs_inode.i_version = 1;
151 return &ei->vfs_inode;
152}
153
154static void ext2_destroy_inode(struct inode *inode)
155{
156 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
157}
158
159static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
160{
161 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
162
163 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
164 SLAB_CTOR_CONSTRUCTOR) {
165 rwlock_init(&ei->i_meta_lock);
166#ifdef CONFIG_EXT2_FS_XATTR
167 init_rwsem(&ei->xattr_sem);
168#endif
169 inode_init_once(&ei->vfs_inode);
170 }
171}
172
173static int init_inodecache(void)
174{
175 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
176 sizeof(struct ext2_inode_info),
fffb60f9
PJ		 177 0, (SLAB_RECLAIM_ACCOUNT|
178 SLAB_MEM_SPREAD),
1da177e4
LT		 179 init_once, NULL);
180 if (ext2_inode_cachep == NULL)
181 return -ENOMEM;
182 return 0;
183}
184
185static void destroy_inodecache(void)
186{
187 if (kmem_cache_destroy(ext2_inode_cachep))
188 printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n");
189}
190
191static void ext2_clear_inode(struct inode *inode)
192{
193#ifdef CONFIG_EXT2_FS_POSIX_ACL
194 struct ext2_inode_info *ei = EXT2_I(inode);
195
196 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
197 posix_acl_release(ei->i_acl);
198 ei->i_acl = EXT2_ACL_NOT_CACHED;
199 }
200 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
201 posix_acl_release(ei->i_default_acl);
202 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
203 }
204#endif
1da177e4
LT		 205}
206
8fc2751b
MB		 207static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
208{
209 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
210
211 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
212 seq_puts(seq, ",grpid");
8fc2751b
MB		 213
214#if defined(CONFIG_QUOTA)
215 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
216 seq_puts(seq, ",usrquota");
217
218 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
219 seq_puts(seq, ",grpquota");
220#endif
221
83541796
CO		 222#if defined(CONFIG_EXT2_FS_XIP)
223 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
224 seq_puts(seq, ",xip");
225#endif
226
8fc2751b
MB		 227 return 0;
228}
229
1da177e4
LT		 230#ifdef CONFIG_QUOTA
231static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
232static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
233#endif
234
235static struct super_operations ext2_sops = {
236 .alloc_inode = ext2_alloc_inode,
237 .destroy_inode = ext2_destroy_inode,
238 .read_inode = ext2_read_inode,
239 .write_inode = ext2_write_inode,
e072c6f2 240 .put_inode = ext2_put_inode,
1da177e4
LT		 241 .delete_inode = ext2_delete_inode,
242 .put_super = ext2_put_super,
243 .write_super = ext2_write_super,
244 .statfs = ext2_statfs,
245 .remount_fs = ext2_remount,
246 .clear_inode = ext2_clear_inode,
8fc2751b 247 .show_options = ext2_show_options,
1da177e4
LT		 248#ifdef CONFIG_QUOTA
249 .quota_read = ext2_quota_read,
250 .quota_write = ext2_quota_write,
251#endif
252};
253
254/* Yes, most of these are left as NULL!!
255 * A NULL value implies the default, which works with ext2-like file
256 * systems, but can be improved upon.
257 * Currently only get_parent is required.
258 */
1da177e4
LT		 259static struct export_operations ext2_export_ops = {
260 .get_parent = ext2_get_parent,
261};
262
263static unsigned long get_sb_block(void **data)
264{
265 unsigned long sb_block;
266 char *options = (char *) *data;
267
268 if (!options || strncmp(options, "sb=", 3) != 0)
269 return 1; /* Default location */
270 options += 3;
271 sb_block = simple_strtoul(options, &options, 0);
272 if (*options && *options != ',') {
273 printk("EXT2-fs: Invalid sb specification: %s\n",
274 (char *) *data);
275 return 1;
276 }
277 if (*options == ',')
278 options++;
279 *data = (void *) options;
280 return sb_block;
281}
282
283enum {
284 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
8fc2751b 285 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
2860b733 286 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
8fc2751b
MB		 287 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
288 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
289 Opt_usrquota, Opt_grpquota
1da177e4
LT		 290};
291
292static match_table_t tokens = {
293 {Opt_bsd_df, "bsddf"},
294 {Opt_minix_df, "minixdf"},
295 {Opt_grpid, "grpid"},
296 {Opt_grpid, "bsdgroups"},
297 {Opt_nogrpid, "nogrpid"},
298 {Opt_nogrpid, "sysvgroups"},
299 {Opt_resgid, "resgid=%u"},
300 {Opt_resuid, "resuid=%u"},
301 {Opt_sb, "sb=%u"},
302 {Opt_err_cont, "errors=continue"},
303 {Opt_err_panic, "errors=panic"},
304 {Opt_err_ro, "errors=remount-ro"},
305 {Opt_nouid32, "nouid32"},
306 {Opt_nocheck, "check=none"},
307 {Opt_nocheck, "nocheck"},
1da177e4
LT		 308 {Opt_debug, "debug"},
309 {Opt_oldalloc, "oldalloc"},
310 {Opt_orlov, "orlov"},
311 {Opt_nobh, "nobh"},
312 {Opt_user_xattr, "user_xattr"},
313 {Opt_nouser_xattr, "nouser_xattr"},
314 {Opt_acl, "acl"},
315 {Opt_noacl, "noacl"},
6d79125b 316 {Opt_xip, "xip"},
8fc2751b 317 {Opt_grpquota, "grpquota"},
1da177e4 318 {Opt_ignore, "noquota"},
8fc2751b
MB		 319 {Opt_quota, "quota"},
320 {Opt_usrquota, "usrquota"},
1da177e4
LT		 321 {Opt_err, NULL}
322};
323
324static int parse_options (char * options,
325 struct ext2_sb_info *sbi)
326{
327 char * p;
328 substring_t args[MAX_OPT_ARGS];
329 unsigned long kind = EXT2_MOUNT_ERRORS_CONT;
330 int option;
331
332 if (!options)
333 return 1;
334
335 while ((p = strsep (&options, ",")) != NULL) {
336 int token;
337 if (!*p)
338 continue;
339
340 token = match_token(p, tokens, args);
341 switch (token) {
342 case Opt_bsd_df:
343 clear_opt (sbi->s_mount_opt, MINIX_DF);
344 break;
345 case Opt_minix_df:
346 set_opt (sbi->s_mount_opt, MINIX_DF);
347 break;
348 case Opt_grpid:
349 set_opt (sbi->s_mount_opt, GRPID);
350 break;
351 case Opt_nogrpid:
352 clear_opt (sbi->s_mount_opt, GRPID);
353 break;
354 case Opt_resuid:
355 if (match_int(&args[0], &option))
356 return 0;
357 sbi->s_resuid = option;
358 break;
359 case Opt_resgid:
360 if (match_int(&args[0], &option))
361 return 0;
362 sbi->s_resgid = option;
363 break;
364 case Opt_sb:
365 /* handled by get_sb_block() instead of here */
366 /* *sb_block = match_int(&args[0]); */
367 break;
368 case Opt_err_panic:
369 kind = EXT2_MOUNT_ERRORS_PANIC;
370 break;
371 case Opt_err_ro:
372 kind = EXT2_MOUNT_ERRORS_RO;
373 break;
374 case Opt_err_cont:
375 kind = EXT2_MOUNT_ERRORS_CONT;
376 break;
377 case Opt_nouid32:
378 set_opt (sbi->s_mount_opt, NO_UID32);
379 break;
1da177e4
LT		 380 case Opt_nocheck:
381 clear_opt (sbi->s_mount_opt, CHECK);
382 break;
383 case Opt_debug:
384 set_opt (sbi->s_mount_opt, DEBUG);
385 break;
386 case Opt_oldalloc:
387 set_opt (sbi->s_mount_opt, OLDALLOC);
388 break;
389 case Opt_orlov:
390 clear_opt (sbi->s_mount_opt, OLDALLOC);
391 break;
392 case Opt_nobh:
393 set_opt (sbi->s_mount_opt, NOBH);
394 break;
395#ifdef CONFIG_EXT2_FS_XATTR
396 case Opt_user_xattr:
397 set_opt (sbi->s_mount_opt, XATTR_USER);
398 break;
399 case Opt_nouser_xattr:
400 clear_opt (sbi->s_mount_opt, XATTR_USER);
401 break;
402#else
403 case Opt_user_xattr:
404 case Opt_nouser_xattr:
405 printk("EXT2 (no)user_xattr options not supported\n");
406 break;
407#endif
408#ifdef CONFIG_EXT2_FS_POSIX_ACL
409 case Opt_acl:
410 set_opt(sbi->s_mount_opt, POSIX_ACL);
411 break;
412 case Opt_noacl:
413 clear_opt(sbi->s_mount_opt, POSIX_ACL);
414 break;
415#else
416 case Opt_acl:
417 case Opt_noacl:
418 printk("EXT2 (no)acl options not supported\n");
419 break;
420#endif
6d79125b
CO		 421 case Opt_xip:
422#ifdef CONFIG_EXT2_FS_XIP
423 set_opt (sbi->s_mount_opt, XIP);
424#else
425 printk("EXT2 xip option not supported\n");
426#endif
427 break;
8fc2751b
MB		 428
429#if defined(CONFIG_QUOTA)
430 case Opt_quota:
431 case Opt_usrquota:
432 set_opt(sbi->s_mount_opt, USRQUOTA);
433 break;
434
435 case Opt_grpquota:
436 set_opt(sbi->s_mount_opt, GRPQUOTA);
437 break;
438#else
439 case Opt_quota:
440 case Opt_usrquota:
441 case Opt_grpquota:
442 printk(KERN_ERR
443 "EXT2-fs: quota operations not supported.\n");
444
445 break;
446#endif
447
1da177e4
LT		 448 case Opt_ignore:
449 break;
450 default:
451 return 0;
452 }
453 }
454 sbi->s_mount_opt |= kind;
455 return 1;
456}
457
458static int ext2_setup_super (struct super_block * sb,
459 struct ext2_super_block * es,
460 int read_only)
461{
462 int res = 0;
463 struct ext2_sb_info *sbi = EXT2_SB(sb);
464
465 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
466 printk ("EXT2-fs warning: revision level too high, "
467 "forcing read-only mode\n");
468 res = MS_RDONLY;
469 }
470 if (read_only)
471 return res;
472 if (!(sbi->s_mount_state & EXT2_VALID_FS))
473 printk ("EXT2-fs warning: mounting unchecked fs, "
474 "running e2fsck is recommended\n");
475 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
476 printk ("EXT2-fs warning: mounting fs with errors, "
477 "running e2fsck is recommended\n");
478 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
479 le16_to_cpu(es->s_mnt_count) >=
480 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
481 printk ("EXT2-fs warning: maximal mount count reached, "
482 "running e2fsck is recommended\n");
483 else if (le32_to_cpu(es->s_checkinterval) &&
484 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
485 printk ("EXT2-fs warning: checktime reached, "
486 "running e2fsck is recommended\n");
487 if (!le16_to_cpu(es->s_max_mnt_count))
488 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
489 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
490 ext2_write_super(sb);
491 if (test_opt (sb, DEBUG))
492 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
493 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
494 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
495 sbi->s_frag_size,
496 sbi->s_groups_count,
497 EXT2_BLOCKS_PER_GROUP(sb),
498 EXT2_INODES_PER_GROUP(sb),
499 sbi->s_mount_opt);
1da177e4
LT		 500 return res;
501}
502
503static int ext2_check_descriptors (struct super_block * sb)
504{
505 int i;
506 int desc_block = 0;
507 struct ext2_sb_info *sbi = EXT2_SB(sb);
508 unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block);
509 struct ext2_group_desc * gdp = NULL;
510
511 ext2_debug ("Checking group descriptors");
512
513 for (i = 0; i < sbi->s_groups_count; i++)
514 {
515 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
516 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
517 if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
518 le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
519 {
520 ext2_error (sb, "ext2_check_descriptors",
521 "Block bitmap for group %d"
522 " not in group (block %lu)!",
523 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
524 return 0;
525 }
526 if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
527 le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
528 {
529 ext2_error (sb, "ext2_check_descriptors",
530 "Inode bitmap for group %d"
531 " not in group (block %lu)!",
532 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
533 return 0;
534 }
535 if (le32_to_cpu(gdp->bg_inode_table) < block ||
536 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >=
537 block + EXT2_BLOCKS_PER_GROUP(sb))
538 {
539 ext2_error (sb, "ext2_check_descriptors",
540 "Inode table for group %d"
541 " not in group (block %lu)!",
542 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
543 return 0;
544 }
545 block += EXT2_BLOCKS_PER_GROUP(sb);
546 gdp++;
547 }
548 return 1;
549}
550
551#define log2(n) ffz(~(n))
552
553/*
554 * Maximal file size. There is a direct, and {,double-,triple-}indirect
555 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
556 * We need to be 1 filesystem block less than the 2^32 sector limit.
557 */
558static loff_t ext2_max_size(int bits)
559{
560 loff_t res = EXT2_NDIR_BLOCKS;
561 /* This constant is calculated to be the largest file size for a
562 * dense, 4k-blocksize file such that the total number of
563 * sectors in the file, including data and all indirect blocks,
564 * does not exceed 2^32. */
565 const loff_t upper_limit = 0x1ff7fffd000LL;
566
567 res += 1LL << (bits-2);
568 res += 1LL << (2*(bits-2));
569 res += 1LL << (3*(bits-2));
570 res <<= bits;
571 if (res > upper_limit)
572 res = upper_limit;
573 return res;
574}
575
576static unsigned long descriptor_loc(struct super_block *sb,
577 unsigned long logic_sb_block,
578 int nr)
579{
580 struct ext2_sb_info *sbi = EXT2_SB(sb);
581 unsigned long bg, first_data_block, first_meta_bg;
582 int has_super = 0;
583
584 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
585 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
586
587 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
588 nr < first_meta_bg)
589 return (logic_sb_block + nr + 1);
590 bg = sbi->s_desc_per_block * nr;
591 if (ext2_bg_has_super(sb, bg))
592 has_super = 1;
593 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
594}
595
596static int ext2_fill_super(struct super_block *sb, void *data, int silent)
597{
598 struct buffer_head * bh;
599 struct ext2_sb_info * sbi;
600 struct ext2_super_block * es;
601 struct inode *root;
602 unsigned long block;
603 unsigned long sb_block = get_sb_block(&data);
604 unsigned long logic_sb_block;
605 unsigned long offset = 0;
606 unsigned long def_mount_opts;
607 int blocksize = BLOCK_SIZE;
608 int db_count;
609 int i, j;
610 __le32 features;
611
612 sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
613 if (!sbi)
614 return -ENOMEM;
615 sb->s_fs_info = sbi;
616 memset(sbi, 0, sizeof(*sbi));
617
618 /*
619 * See what the current blocksize for the device is, and
620 * use that as the blocksize. Otherwise (or if the blocksize
621 * is smaller than the default) use the default.
622 * This is important for devices that have a hardware
623 * sectorsize that is larger than the default.
624 */
625 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
626 if (!blocksize) {
627 printk ("EXT2-fs: unable to set blocksize\n");
628 goto failed_sbi;
629 }
630
631 /*
632 * If the superblock doesn't start on a hardware sector boundary,
633 * calculate the offset.
634 */
635 if (blocksize != BLOCK_SIZE) {
636 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
637 offset = (sb_block*BLOCK_SIZE) % blocksize;
638 } else {
639 logic_sb_block = sb_block;
640 }
641
642 if (!(bh = sb_bread(sb, logic_sb_block))) {
643 printk ("EXT2-fs: unable to read superblock\n");
644 goto failed_sbi;
645 }
646 /*
647 * Note: s_es must be initialized as soon as possible because
648 * some ext2 macro-instructions depend on its value
649 */
650 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
651 sbi->s_es = es;
652 sb->s_magic = le16_to_cpu(es->s_magic);
653
654 if (sb->s_magic != EXT2_SUPER_MAGIC)
655 goto cantfind_ext2;
656
657 /* Set defaults before we parse the mount options */
658 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
659 if (def_mount_opts & EXT2_DEFM_DEBUG)
660 set_opt(sbi->s_mount_opt, DEBUG);
661 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
662 set_opt(sbi->s_mount_opt, GRPID);
663 if (def_mount_opts & EXT2_DEFM_UID16)
664 set_opt(sbi->s_mount_opt, NO_UID32);
665 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
666 set_opt(sbi->s_mount_opt, XATTR_USER);
667 if (def_mount_opts & EXT2_DEFM_ACL)
668 set_opt(sbi->s_mount_opt, POSIX_ACL);
669
670 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
671 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
672 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
673 set_opt(sbi->s_mount_opt, ERRORS_RO);
674
675 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
676 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
677
678 if (!parse_options ((char *) data, sbi))
679 goto failed_mount;
680
681 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
682 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
683 MS_POSIXACL : 0);
684
6d79125b
CO		 685 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
686 EXT2_MOUNT_XIP if not */
687
1da177e4
LT		 688 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
689 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
690 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
691 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
692 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
693 "running e2fsck is recommended\n");
694 /*
695 * Check feature flags regardless of the revision level, since we
696 * previously didn't change the revision level when setting the flags,
697 * so there is a chance incompat flags are set on a rev 0 filesystem.
698 */
699 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
700 if (features) {
701 printk("EXT2-fs: %s: couldn't mount because of "
702 "unsupported optional features (%x).\n",
703 sb->s_id, le32_to_cpu(features));
704 goto failed_mount;
705 }
706 if (!(sb->s_flags & MS_RDONLY) &&
707 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
708 printk("EXT2-fs: %s: couldn't mount RDWR because of "
709 "unsupported optional features (%x).\n",
710 sb->s_id, le32_to_cpu(features));
711 goto failed_mount;
712 }
713
714 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
715
6d79125b
CO		 716 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
717 (sb->s_blocksize != blocksize))) {
718 if (!silent)
719 printk("XIP: Unsupported blocksize\n");
720 goto failed_mount;
721 }
722
1da177e4
LT		 723 /* If the blocksize doesn't match, re-read the thing.. */
724 if (sb->s_blocksize != blocksize) {
725 brelse(bh);
726
727 if (!sb_set_blocksize(sb, blocksize)) {
728 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
729 goto failed_sbi;
730 }
731
732 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
733 offset = (sb_block*BLOCK_SIZE) % blocksize;
734 bh = sb_bread(sb, logic_sb_block);
735 if(!bh) {
736 printk("EXT2-fs: Couldn't read superblock on "
737 "2nd try.\n");
738 goto failed_sbi;
739 }
740 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
741 sbi->s_es = es;
742 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
743 printk ("EXT2-fs: Magic mismatch, very weird !\n");
744 goto failed_mount;
745 }
746 }
747
748 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
749
750 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
751 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
752 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
753 } else {
754 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
755 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
756 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
757 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
758 (sbi->s_inode_size > blocksize)) {
759 printk ("EXT2-fs: unsupported inode size: %d\n",
760 sbi->s_inode_size);
761 goto failed_mount;
762 }
763 }
764
765 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
766 le32_to_cpu(es->s_log_frag_size);
767 if (sbi->s_frag_size == 0)
768 goto cantfind_ext2;
769 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
770
771 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
772 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
773 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
774
775 if (EXT2_INODE_SIZE(sb) == 0)
776 goto cantfind_ext2;
777 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
778 if (sbi->s_inodes_per_block == 0)
779 goto cantfind_ext2;
780 sbi->s_itb_per_group = sbi->s_inodes_per_group /
781 sbi->s_inodes_per_block;
782 sbi->s_desc_per_block = sb->s_blocksize /
783 sizeof (struct ext2_group_desc);
784 sbi->s_sbh = bh;
785 sbi->s_mount_state = le16_to_cpu(es->s_state);
786 sbi->s_addr_per_block_bits =
787 log2 (EXT2_ADDR_PER_BLOCK(sb));
788 sbi->s_desc_per_block_bits =
789 log2 (EXT2_DESC_PER_BLOCK(sb));
790
791 if (sb->s_magic != EXT2_SUPER_MAGIC)
792 goto cantfind_ext2;
793
794 if (sb->s_blocksize != bh->b_size) {
795 if (!silent)
796 printk ("VFS: Unsupported blocksize on dev "
797 "%s.\n", sb->s_id);
798 goto failed_mount;
799 }
800
801 if (sb->s_blocksize != sbi->s_frag_size) {
802 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
803 sbi->s_frag_size, sb->s_blocksize);
804 goto failed_mount;
805 }
806
807 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
808 printk ("EXT2-fs: #blocks per group too big: %lu\n",
809 sbi->s_blocks_per_group);
810 goto failed_mount;
811 }
812 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
813 printk ("EXT2-fs: #fragments per group too big: %lu\n",
814 sbi->s_frags_per_group);
815 goto failed_mount;
816 }
817 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
818 printk ("EXT2-fs: #inodes per group too big: %lu\n",
819 sbi->s_inodes_per_group);
820 goto failed_mount;
821 }
822
823 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
824 goto cantfind_ext2;
825 sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
826 le32_to_cpu(es->s_first_data_block) +
827 EXT2_BLOCKS_PER_GROUP(sb) - 1) /
828 EXT2_BLOCKS_PER_GROUP(sb);
829 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
830 EXT2_DESC_PER_BLOCK(sb);
831 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
832 if (sbi->s_group_desc == NULL) {
833 printk ("EXT2-fs: not enough memory\n");
834 goto failed_mount;
835 }
1da177e4
LT		 836 bgl_lock_init(&sbi->s_blockgroup_lock);
837 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
838 GFP_KERNEL);
839 if (!sbi->s_debts) {
840 printk ("EXT2-fs: not enough memory\n");
841 goto failed_mount_group_desc;
842 }
843 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
844 for (i = 0; i < db_count; i++) {
845 block = descriptor_loc(sb, logic_sb_block, i);
846 sbi->s_group_desc[i] = sb_bread(sb, block);
847 if (!sbi->s_group_desc[i]) {
848 for (j = 0; j < i; j++)
849 brelse (sbi->s_group_desc[j]);
850 printk ("EXT2-fs: unable to read group descriptors\n");
851 goto failed_mount_group_desc;
852 }
853 }
854 if (!ext2_check_descriptors (sb)) {
855 printk ("EXT2-fs: group descriptors corrupted!\n");
1da177e4
LT		 856 goto failed_mount2;
857 }
858 sbi->s_gdb_count = db_count;
859 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
860 spin_lock_init(&sbi->s_next_gen_lock);
0216bfcf
MC		 861
862 percpu_counter_init(&sbi->s_freeblocks_counter,
863 ext2_count_free_blocks(sb));
864 percpu_counter_init(&sbi->s_freeinodes_counter,
865 ext2_count_free_inodes(sb));
866 percpu_counter_init(&sbi->s_dirs_counter,
867 ext2_count_dirs(sb));
1da177e4
LT		 868 /*
869 * set up enough so that it can read an inode
870 */
871 sb->s_op = &ext2_sops;
872 sb->s_export_op = &ext2_export_ops;
873 sb->s_xattr = ext2_xattr_handlers;
874 root = iget(sb, EXT2_ROOT_INO);
875 sb->s_root = d_alloc_root(root);
876 if (!sb->s_root) {
877 iput(root);
878 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
0216bfcf 879 goto failed_mount3;
1da177e4
LT		 880 }
881 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
882 dput(sb->s_root);
883 sb->s_root = NULL;
884 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
0216bfcf 885 goto failed_mount3;
1da177e4
LT		 886 }
887 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
888 ext2_warning(sb, __FUNCTION__,
ec63f22d 889 "mounting ext3 filesystem as ext2");
1da177e4 890 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
1da177e4
LT		 891 return 0;
892
893cantfind_ext2:
894 if (!silent)
895 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
896 sb->s_id);
897 goto failed_mount;
0216bfcf
MC		 898failed_mount3:
899 percpu_counter_destroy(&sbi->s_freeblocks_counter);
900 percpu_counter_destroy(&sbi->s_freeinodes_counter);
901 percpu_counter_destroy(&sbi->s_dirs_counter);
1da177e4
LT		 902failed_mount2:
903 for (i = 0; i < db_count; i++)
904 brelse(sbi->s_group_desc[i]);
905failed_mount_group_desc:
906 kfree(sbi->s_group_desc);
907 kfree(sbi->s_debts);
908failed_mount:
909 brelse(bh);
910failed_sbi:
911 sb->s_fs_info = NULL;
912 kfree(sbi);
913 return -EINVAL;
914}
915
916static void ext2_commit_super (struct super_block * sb,
917 struct ext2_super_block * es)
918{
919 es->s_wtime = cpu_to_le32(get_seconds());
920 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
921 sb->s_dirt = 0;
922}
923
924static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
925{
926 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
927 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
928 es->s_wtime = cpu_to_le32(get_seconds());
929 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
930 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
931 sb->s_dirt = 0;
932}
933
934/*
935 * In the second extended file system, it is not necessary to
936 * write the super block since we use a mapping of the
937 * disk super block in a buffer.
938 *
939 * However, this function is still used to set the fs valid
940 * flags to 0. We need to set this flag to 0 since the fs
941 * may have been checked while mounted and e2fsck may have
942 * set s_state to EXT2_VALID_FS after some corrections.
943 */
944
945void ext2_write_super (struct super_block * sb)
946{
947 struct ext2_super_block * es;
948 lock_kernel();
949 if (!(sb->s_flags & MS_RDONLY)) {
950 es = EXT2_SB(sb)->s_es;
951
952 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
953 ext2_debug ("setting valid to 0\n");
954 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
955 ~EXT2_VALID_FS);
956 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
957 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
958 es->s_mtime = cpu_to_le32(get_seconds());
959 ext2_sync_super(sb, es);
960 } else
961 ext2_commit_super (sb, es);
962 }
963 sb->s_dirt = 0;
964 unlock_kernel();
965}
966
967static int ext2_remount (struct super_block * sb, int * flags, char * data)
968{
969 struct ext2_sb_info * sbi = EXT2_SB(sb);
970 struct ext2_super_block * es;
6d79125b 971 unsigned long old_mount_opt = sbi->s_mount_opt;
50a52234
JK		 972 struct ext2_mount_options old_opts;
973 unsigned long old_sb_flags;
974 int err;
975
976 /* Store the old options */
977 old_sb_flags = sb->s_flags;
978 old_opts.s_mount_opt = sbi->s_mount_opt;
979 old_opts.s_resuid = sbi->s_resuid;
980 old_opts.s_resgid = sbi->s_resgid;
1da177e4
LT		 981
982 /*
983 * Allow the "check" option to be passed as a remount option.
984 */
50a52234
JK		 985 if (!parse_options (data, sbi)) {
986 err = -EINVAL;
987 goto restore_opts;
988 }
1da177e4
LT		 989
990 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
991 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
992
993 es = sbi->s_es;
6d79125b
CO		 994 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
995 (old_mount_opt & EXT2_MOUNT_XIP)) &&
996 invalidate_inodes(sb))
997 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
998 "xip remain in cache (no functional problem)");
1da177e4
LT		 999 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1000 return 0;
1001 if (*flags & MS_RDONLY) {
1002 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1003 !(sbi->s_mount_state & EXT2_VALID_FS))
1004 return 0;
1005 /*
1006 * OK, we are remounting a valid rw partition rdonly, so set
1007 * the rdonly flag and then mark the partition as valid again.
1008 */
1009 es->s_state = cpu_to_le16(sbi->s_mount_state);
1010 es->s_mtime = cpu_to_le32(get_seconds());
1011 } else {
1012 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1013 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1014 if (ret) {
1015 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1016 "unsupported optional features (%x).\n",
1017 sb->s_id, le32_to_cpu(ret));
50a52234
JK		 1018 err = -EROFS;
1019 goto restore_opts;
1da177e4
LT		 1020 }
1021 /*
1022 * Mounting a RDONLY partition read-write, so reread and
1023 * store the current valid flag. (It may have been changed
1024 * by e2fsck since we originally mounted the partition.)
1025 */
1026 sbi->s_mount_state = le16_to_cpu(es->s_state);
1027 if (!ext2_setup_super (sb, es, 0))
1028 sb->s_flags &= ~MS_RDONLY;
1029 }
1030 ext2_sync_super(sb, es);
1031 return 0;
50a52234
JK		 1032restore_opts:
1033 sbi->s_mount_opt = old_opts.s_mount_opt;
1034 sbi->s_resuid = old_opts.s_resuid;
1035 sbi->s_resgid = old_opts.s_resgid;
1036 sb->s_flags = old_sb_flags;
1037 return err;
1da177e4
LT		 1038}
1039
726c3342 1040static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1da177e4 1041{
726c3342 1042 struct super_block *sb = dentry->d_sb;
1da177e4
LT		 1043 struct ext2_sb_info *sbi = EXT2_SB(sb);
1044 unsigned long overhead;
1045 int i;
1046
21730eed 1047 lock_super(sb);
1da177e4
LT		 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;
21730eed 1088 unlock_super(sb);
1da177e4
LT		 1089 return 0;
1090}
1091
454e2398
DH		 1092static int ext2_get_sb(struct file_system_type *fs_type,
1093 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1da177e4 1094{
454e2398 1095 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1da177e4
LT		 1096}
1097
1098#ifdef CONFIG_QUOTA
1099
1100/* Read data from quotafile - avoid pagecache and such because we cannot afford
1101 * acquiring the locks... As quota files are never truncated and quota code
1102 * itself serializes the operations (and noone else should touch the files)
1103 * we don't have to be afraid of races */
1104static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1105 size_t len, loff_t off)
1106{
1107 struct inode *inode = sb_dqopt(sb)->files[type];
1108 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1109 int err = 0;
1110 int offset = off & (sb->s_blocksize - 1);
1111 int tocopy;
1112 size_t toread;
1113 struct buffer_head tmp_bh;
1114 struct buffer_head *bh;
1115 loff_t i_size = i_size_read(inode);
1116
1117 if (off > i_size)
1118 return 0;
1119 if (off+len > i_size)
1120 len = i_size-off;
1121 toread = len;
1122 while (toread > 0) {
1123 tocopy = sb->s_blocksize - offset < toread ?
1124 sb->s_blocksize - offset : toread;
1125
1126 tmp_bh.b_state = 0;
1127 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1128 if (err)
1129 return err;
1130 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1131 memset(data, 0, tocopy);
1132 else {
1133 bh = sb_bread(sb, tmp_bh.b_blocknr);
1134 if (!bh)
1135 return -EIO;
1136 memcpy(data, bh->b_data+offset, tocopy);
1137 brelse(bh);
1138 }
1139 offset = 0;
1140 toread -= tocopy;
1141 data += tocopy;
1142 blk++;
1143 }
1144 return len;
1145}
1146
1147/* Write to quotafile */
1148static ssize_t ext2_quota_write(struct super_block *sb, int type,
1149 const char *data, size_t len, loff_t off)
1150{
1151 struct inode *inode = sb_dqopt(sb)->files[type];
1152 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1153 int err = 0;
1154 int offset = off & (sb->s_blocksize - 1);
1155 int tocopy;
1156 size_t towrite = len;
1157 struct buffer_head tmp_bh;
1158 struct buffer_head *bh;
1159
5c81a419 1160 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1da177e4
LT		 1161 while (towrite > 0) {
1162 tocopy = sb->s_blocksize - offset < towrite ?
1163 sb->s_blocksize - offset : towrite;
1164
1165 tmp_bh.b_state = 0;
1166 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1167 if (err)
1168 goto out;
1169 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1170 bh = sb_bread(sb, tmp_bh.b_blocknr);
1171 else
1172 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1173 if (!bh) {
1174 err = -EIO;
1175 goto out;
1176 }
1177 lock_buffer(bh);
1178 memcpy(bh->b_data+offset, data, tocopy);
1179 flush_dcache_page(bh->b_page);
1180 set_buffer_uptodate(bh);
1181 mark_buffer_dirty(bh);
1182 unlock_buffer(bh);
1183 brelse(bh);
1184 offset = 0;
1185 towrite -= tocopy;
1186 data += tocopy;
1187 blk++;
1188 }
1189out:
1190 if (len == towrite)
1191 return err;
1192 if (inode->i_size < off+len-towrite)
1193 i_size_write(inode, off+len-towrite);
1194 inode->i_version++;
1195 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1196 mark_inode_dirty(inode);
1b1dcc1b 1197 mutex_unlock(&inode->i_mutex);
1da177e4
LT		 1198 return len - towrite;
1199}
1200
1201#endif
1202
1203static struct file_system_type ext2_fs_type = {
1204 .owner = THIS_MODULE,
1205 .name = "ext2",
1206 .get_sb = ext2_get_sb,
1207 .kill_sb = kill_block_super,
1208 .fs_flags = FS_REQUIRES_DEV,
1209};
1210
1211static int __init init_ext2_fs(void)
1212{
1213 int err = init_ext2_xattr();
1214 if (err)
1215 return err;
1216 err = init_inodecache();
1217 if (err)
1218 goto out1;
1219 err = register_filesystem(&ext2_fs_type);
1220 if (err)
1221 goto out;
1222 return 0;
1223out:
1224 destroy_inodecache();
1225out1:
1226 exit_ext2_xattr();
1227 return err;
1228}
1229
1230static void __exit exit_ext2_fs(void)
1231{
1232 unregister_filesystem(&ext2_fs_type);
1233 destroy_inodecache();
1234 exit_ext2_xattr();
1235}
1236
1237module_init(init_ext2_fs)
1238module_exit(exit_ext2_fs)
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