?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
firewire: Loop requests to the host controller back into the stack.
[linux-2.6/mini2440.git] / fs / ext2 / super.c
bloba046a419d8afd65a87671a7963da8b2cf3a0b887
1 /*
2 * linux/fs/ext2/super.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/inode.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * Big-endian to little-endian byte-swapping/bitmaps by
16 * David S. Miller (davem@caip.rutgers.edu), 1995
17 */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/slab.h>
23 #include <linux/init.h>
24 #include <linux/blkdev.h>
25 #include <linux/parser.h>
26 #include <linux/random.h>
27 #include <linux/buffer_head.h>
28 #include <linux/smp_lock.h>
29 #include <linux/vfs.h>
30 #include <linux/seq_file.h>
31 #include <linux/mount.h>
32 #include <asm/uaccess.h>
33 #include "ext2.h"
34 #include "xattr.h"
35 #include "acl.h"
36 #include "xip.h"
37
38 static void ext2_sync_super(struct super_block *sb,
39 struct ext2_super_block *es);
40 static int ext2_remount (struct super_block * sb, int * flags, char * data);
41 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
42
43 void 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
71 void 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
84 void 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
109 static 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
138 static struct kmem_cache * ext2_inode_cachep;
139
140 static 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, GFP_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
154 static void ext2_destroy_inode(struct inode *inode)
155 {
156 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
157 }
158
159 static void init_once(void * foo, struct kmem_cache * 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
173 static int init_inodecache(void)
174 {
175 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
176 sizeof(struct ext2_inode_info),
177 0, (SLAB_RECLAIM_ACCOUNT|
178 SLAB_MEM_SPREAD),
179 init_once, NULL);
180 if (ext2_inode_cachep == NULL)
181 return -ENOMEM;
182 return 0;
183 }
184
185 static void destroy_inodecache(void)
186 {
187 kmem_cache_destroy(ext2_inode_cachep);
188 }
189
190 static void ext2_clear_inode(struct inode *inode)
191 {
192 #ifdef CONFIG_EXT2_FS_POSIX_ACL
193 struct ext2_inode_info *ei = EXT2_I(inode);
194
195 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
196 posix_acl_release(ei->i_acl);
197 ei->i_acl = EXT2_ACL_NOT_CACHED;
198 }
199 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
200 posix_acl_release(ei->i_default_acl);
201 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
202 }
203 #endif
204 }
205
206 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
207 {
208 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
209
210 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
211 seq_puts(seq, ",grpid");
212
213 #if defined(CONFIG_QUOTA)
214 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
215 seq_puts(seq, ",usrquota");
216
217 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
218 seq_puts(seq, ",grpquota");
219 #endif
220
221 #if defined(CONFIG_EXT2_FS_XIP)
222 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
223 seq_puts(seq, ",xip");
224 #endif
225
226 return 0;
227 }
228
229 #ifdef CONFIG_QUOTA
230 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
231 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
232 #endif
233
234 static const struct super_operations ext2_sops = {
235 .alloc_inode = ext2_alloc_inode,
236 .destroy_inode = ext2_destroy_inode,
237 .read_inode = ext2_read_inode,
238 .write_inode = ext2_write_inode,
239 .put_inode = ext2_put_inode,
240 .delete_inode = ext2_delete_inode,
241 .put_super = ext2_put_super,
242 .write_super = ext2_write_super,
243 .statfs = ext2_statfs,
244 .remount_fs = ext2_remount,
245 .clear_inode = ext2_clear_inode,
246 .show_options = ext2_show_options,
247 #ifdef CONFIG_QUOTA
248 .quota_read = ext2_quota_read,
249 .quota_write = ext2_quota_write,
250 #endif
251 };
252
253 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp)
254 {
255 __u32 *objp = vobjp;
256 unsigned long ino = objp[0];
257 __u32 generation = objp[1];
258 struct inode *inode;
259 struct dentry *result;
260
261 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
262 return ERR_PTR(-ESTALE);
263 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
264 return ERR_PTR(-ESTALE);
265
266 /* iget isn't really right if the inode is currently unallocated!!
267 * ext2_read_inode currently does appropriate checks, but
268 * it might be "neater" to call ext2_get_inode first and check
269 * if the inode is valid.....
270 */
271 inode = iget(sb, ino);
272 if (inode == NULL)
273 return ERR_PTR(-ENOMEM);
274 if (is_bad_inode(inode) ||
275 (generation && inode->i_generation != generation)) {
276 /* we didn't find the right inode.. */
277 iput(inode);
278 return ERR_PTR(-ESTALE);
279 }
280 /* now to find a dentry.
281 * If possible, get a well-connected one
282 */
283 result = d_alloc_anon(inode);
284 if (!result) {
285 iput(inode);
286 return ERR_PTR(-ENOMEM);
287 }
288 return result;
289 }
290
291 /* Yes, most of these are left as NULL!!
292 * A NULL value implies the default, which works with ext2-like file
293 * systems, but can be improved upon.
294 * Currently only get_parent is required.
295 */
296 static struct export_operations ext2_export_ops = {
297 .get_parent = ext2_get_parent,
298 .get_dentry = ext2_get_dentry,
299 };
300
301 static unsigned long get_sb_block(void **data)
302 {
303 unsigned long sb_block;
304 char *options = (char *) *data;
305
306 if (!options || strncmp(options, "sb=", 3) != 0)
307 return 1; /* Default location */
308 options += 3;
309 sb_block = simple_strtoul(options, &options, 0);
310 if (*options && *options != ',') {
311 printk("EXT2-fs: Invalid sb specification: %s\n",
312 (char *) *data);
313 return 1;
314 }
315 if (*options == ',')
316 options++;
317 *data = (void *) options;
318 return sb_block;
319 }
320
321 enum {
322 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
323 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
324 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
325 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
326 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
327 Opt_usrquota, Opt_grpquota
328 };
329
330 static match_table_t tokens = {
331 {Opt_bsd_df, "bsddf"},
332 {Opt_minix_df, "minixdf"},
333 {Opt_grpid, "grpid"},
334 {Opt_grpid, "bsdgroups"},
335 {Opt_nogrpid, "nogrpid"},
336 {Opt_nogrpid, "sysvgroups"},
337 {Opt_resgid, "resgid=%u"},
338 {Opt_resuid, "resuid=%u"},
339 {Opt_sb, "sb=%u"},
340 {Opt_err_cont, "errors=continue"},
341 {Opt_err_panic, "errors=panic"},
342 {Opt_err_ro, "errors=remount-ro"},
343 {Opt_nouid32, "nouid32"},
344 {Opt_nocheck, "check=none"},
345 {Opt_nocheck, "nocheck"},
346 {Opt_debug, "debug"},
347 {Opt_oldalloc, "oldalloc"},
348 {Opt_orlov, "orlov"},
349 {Opt_nobh, "nobh"},
350 {Opt_user_xattr, "user_xattr"},
351 {Opt_nouser_xattr, "nouser_xattr"},
352 {Opt_acl, "acl"},
353 {Opt_noacl, "noacl"},
354 {Opt_xip, "xip"},
355 {Opt_grpquota, "grpquota"},
356 {Opt_ignore, "noquota"},
357 {Opt_quota, "quota"},
358 {Opt_usrquota, "usrquota"},
359 {Opt_err, NULL}
360 };
361
362 static int parse_options (char * options,
363 struct ext2_sb_info *sbi)
364 {
365 char * p;
366 substring_t args[MAX_OPT_ARGS];
367 int option;
368
369 if (!options)
370 return 1;
371
372 while ((p = strsep (&options, ",")) != NULL) {
373 int token;
374 if (!*p)
375 continue;
376
377 token = match_token(p, tokens, args);
378 switch (token) {
379 case Opt_bsd_df:
380 clear_opt (sbi->s_mount_opt, MINIX_DF);
381 break;
382 case Opt_minix_df:
383 set_opt (sbi->s_mount_opt, MINIX_DF);
384 break;
385 case Opt_grpid:
386 set_opt (sbi->s_mount_opt, GRPID);
387 break;
388 case Opt_nogrpid:
389 clear_opt (sbi->s_mount_opt, GRPID);
390 break;
391 case Opt_resuid:
392 if (match_int(&args[0], &option))
393 return 0;
394 sbi->s_resuid = option;
395 break;
396 case Opt_resgid:
397 if (match_int(&args[0], &option))
398 return 0;
399 sbi->s_resgid = option;
400 break;
401 case Opt_sb:
402 /* handled by get_sb_block() instead of here */
403 /* *sb_block = match_int(&args[0]); */
404 break;
405 case Opt_err_panic:
406 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
407 clear_opt (sbi->s_mount_opt, ERRORS_RO);
408 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
409 break;
410 case Opt_err_ro:
411 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
412 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
413 set_opt (sbi->s_mount_opt, ERRORS_RO);
414 break;
415 case Opt_err_cont:
416 clear_opt (sbi->s_mount_opt, ERRORS_RO);
417 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
418 set_opt (sbi->s_mount_opt, ERRORS_CONT);
419 break;
420 case Opt_nouid32:
421 set_opt (sbi->s_mount_opt, NO_UID32);
422 break;
423 case Opt_nocheck:
424 clear_opt (sbi->s_mount_opt, CHECK);
425 break;
426 case Opt_debug:
427 set_opt (sbi->s_mount_opt, DEBUG);
428 break;
429 case Opt_oldalloc:
430 set_opt (sbi->s_mount_opt, OLDALLOC);
431 break;
432 case Opt_orlov:
433 clear_opt (sbi->s_mount_opt, OLDALLOC);
434 break;
435 case Opt_nobh:
436 set_opt (sbi->s_mount_opt, NOBH);
437 break;
438 #ifdef CONFIG_EXT2_FS_XATTR
439 case Opt_user_xattr:
440 set_opt (sbi->s_mount_opt, XATTR_USER);
441 break;
442 case Opt_nouser_xattr:
443 clear_opt (sbi->s_mount_opt, XATTR_USER);
444 break;
445 #else
446 case Opt_user_xattr:
447 case Opt_nouser_xattr:
448 printk("EXT2 (no)user_xattr options not supported\n");
449 break;
450 #endif
451 #ifdef CONFIG_EXT2_FS_POSIX_ACL
452 case Opt_acl:
453 set_opt(sbi->s_mount_opt, POSIX_ACL);
454 break;
455 case Opt_noacl:
456 clear_opt(sbi->s_mount_opt, POSIX_ACL);
457 break;
458 #else
459 case Opt_acl:
460 case Opt_noacl:
461 printk("EXT2 (no)acl options not supported\n");
462 break;
463 #endif
464 case Opt_xip:
465 #ifdef CONFIG_EXT2_FS_XIP
466 set_opt (sbi->s_mount_opt, XIP);
467 #else
468 printk("EXT2 xip option not supported\n");
469 #endif
470 break;
471
472 #if defined(CONFIG_QUOTA)
473 case Opt_quota:
474 case Opt_usrquota:
475 set_opt(sbi->s_mount_opt, USRQUOTA);
476 break;
477
478 case Opt_grpquota:
479 set_opt(sbi->s_mount_opt, GRPQUOTA);
480 break;
481 #else
482 case Opt_quota:
483 case Opt_usrquota:
484 case Opt_grpquota:
485 printk(KERN_ERR
486 "EXT2-fs: quota operations not supported.\n");
487
488 break;
489 #endif
490
491 case Opt_ignore:
492 break;
493 default:
494 return 0;
495 }
496 }
497 return 1;
498 }
499
500 static int ext2_setup_super (struct super_block * sb,
501 struct ext2_super_block * es,
502 int read_only)
503 {
504 int res = 0;
505 struct ext2_sb_info *sbi = EXT2_SB(sb);
506
507 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
508 printk ("EXT2-fs warning: revision level too high, "
509 "forcing read-only mode\n");
510 res = MS_RDONLY;
511 }
512 if (read_only)
513 return res;
514 if (!(sbi->s_mount_state & EXT2_VALID_FS))
515 printk ("EXT2-fs warning: mounting unchecked fs, "
516 "running e2fsck is recommended\n");
517 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
518 printk ("EXT2-fs warning: mounting fs with errors, "
519 "running e2fsck is recommended\n");
520 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
521 le16_to_cpu(es->s_mnt_count) >=
522 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
523 printk ("EXT2-fs warning: maximal mount count reached, "
524 "running e2fsck is recommended\n");
525 else if (le32_to_cpu(es->s_checkinterval) &&
526 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
527 printk ("EXT2-fs warning: checktime reached, "
528 "running e2fsck is recommended\n");
529 if (!le16_to_cpu(es->s_max_mnt_count))
530 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
531 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
532 ext2_write_super(sb);
533 if (test_opt (sb, DEBUG))
534 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
535 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
536 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
537 sbi->s_frag_size,
538 sbi->s_groups_count,
539 EXT2_BLOCKS_PER_GROUP(sb),
540 EXT2_INODES_PER_GROUP(sb),
541 sbi->s_mount_opt);
542 return res;
543 }
544
545 static int ext2_check_descriptors (struct super_block * sb)
546 {
547 int i;
548 int desc_block = 0;
549 struct ext2_sb_info *sbi = EXT2_SB(sb);
550 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
551 unsigned long last_block;
552 struct ext2_group_desc * gdp = NULL;
553
554 ext2_debug ("Checking group descriptors");
555
556 for (i = 0; i < sbi->s_groups_count; i++)
557 {
558 if (i == sbi->s_groups_count - 1)
559 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
560 else
561 last_block = first_block +
562 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
563
564 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
565 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
566 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
567 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
568 {
569 ext2_error (sb, "ext2_check_descriptors",
570 "Block bitmap for group %d"
571 " not in group (block %lu)!",
572 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
573 return 0;
574 }
575 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
576 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
577 {
578 ext2_error (sb, "ext2_check_descriptors",
579 "Inode bitmap for group %d"
580 " not in group (block %lu)!",
581 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
582 return 0;
583 }
584 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
585 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
586 last_block)
587 {
588 ext2_error (sb, "ext2_check_descriptors",
589 "Inode table for group %d"
590 " not in group (block %lu)!",
591 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
592 return 0;
593 }
594 first_block += EXT2_BLOCKS_PER_GROUP(sb);
595 gdp++;
596 }
597 return 1;
598 }
599
600 /*
601 * Maximal file size. There is a direct, and {,double-,triple-}indirect
602 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
603 * We need to be 1 filesystem block less than the 2^32 sector limit.
604 */
605 static loff_t ext2_max_size(int bits)
606 {
607 loff_t res = EXT2_NDIR_BLOCKS;
608 /* This constant is calculated to be the largest file size for a
609 * dense, 4k-blocksize file such that the total number of
610 * sectors in the file, including data and all indirect blocks,
611 * does not exceed 2^32. */
612 const loff_t upper_limit = 0x1ff7fffd000LL;
613
614 res += 1LL << (bits-2);
615 res += 1LL << (2*(bits-2));
616 res += 1LL << (3*(bits-2));
617 res <<= bits;
618 if (res > upper_limit)
619 res = upper_limit;
620 return res;
621 }
622
623 static unsigned long descriptor_loc(struct super_block *sb,
624 unsigned long logic_sb_block,
625 int nr)
626 {
627 struct ext2_sb_info *sbi = EXT2_SB(sb);
628 unsigned long bg, first_data_block, first_meta_bg;
629 int has_super = 0;
630
631 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
632 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
633
634 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
635 nr < first_meta_bg)
636 return (logic_sb_block + nr + 1);
637 bg = sbi->s_desc_per_block * nr;
638 if (ext2_bg_has_super(sb, bg))
639 has_super = 1;
640 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
641 }
642
643 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
644 {
645 struct buffer_head * bh;
646 struct ext2_sb_info * sbi;
647 struct ext2_super_block * es;
648 struct inode *root;
649 unsigned long block;
650 unsigned long sb_block = get_sb_block(&data);
651 unsigned long logic_sb_block;
652 unsigned long offset = 0;
653 unsigned long def_mount_opts;
654 int blocksize = BLOCK_SIZE;
655 int db_count;
656 int i, j;
657 __le32 features;
658
659 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
660 if (!sbi)
661 return -ENOMEM;
662 sb->s_fs_info = sbi;
663
664 /*
665 * See what the current blocksize for the device is, and
666 * use that as the blocksize. Otherwise (or if the blocksize
667 * is smaller than the default) use the default.
668 * This is important for devices that have a hardware
669 * sectorsize that is larger than the default.
670 */
671 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
672 if (!blocksize) {
673 printk ("EXT2-fs: unable to set blocksize\n");
674 goto failed_sbi;
675 }
676
677 /*
678 * If the superblock doesn't start on a hardware sector boundary,
679 * calculate the offset.
680 */
681 if (blocksize != BLOCK_SIZE) {
682 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
683 offset = (sb_block*BLOCK_SIZE) % blocksize;
684 } else {
685 logic_sb_block = sb_block;
686 }
687
688 if (!(bh = sb_bread(sb, logic_sb_block))) {
689 printk ("EXT2-fs: unable to read superblock\n");
690 goto failed_sbi;
691 }
692 /*
693 * Note: s_es must be initialized as soon as possible because
694 * some ext2 macro-instructions depend on its value
695 */
696 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
697 sbi->s_es = es;
698 sb->s_magic = le16_to_cpu(es->s_magic);
699
700 if (sb->s_magic != EXT2_SUPER_MAGIC)
701 goto cantfind_ext2;
702
703 /* Set defaults before we parse the mount options */
704 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
705 if (def_mount_opts & EXT2_DEFM_DEBUG)
706 set_opt(sbi->s_mount_opt, DEBUG);
707 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
708 set_opt(sbi->s_mount_opt, GRPID);
709 if (def_mount_opts & EXT2_DEFM_UID16)
710 set_opt(sbi->s_mount_opt, NO_UID32);
711 #ifdef CONFIG_EXT2_FS_XATTR
712 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
713 set_opt(sbi->s_mount_opt, XATTR_USER);
714 #endif
715 #ifdef CONFIG_EXT2_FS_POSIX_ACL
716 if (def_mount_opts & EXT2_DEFM_ACL)
717 set_opt(sbi->s_mount_opt, POSIX_ACL);
718 #endif
719
720 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
721 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
722 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
723 set_opt(sbi->s_mount_opt, ERRORS_RO);
724 else
725 set_opt(sbi->s_mount_opt, ERRORS_CONT);
726
727 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
728 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
729
730 if (!parse_options ((char *) data, sbi))
731 goto failed_mount;
732
733 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
734 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
735 MS_POSIXACL : 0);
736
737 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
738 EXT2_MOUNT_XIP if not */
739
740 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
741 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
742 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
743 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
744 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
745 "running e2fsck is recommended\n");
746 /*
747 * Check feature flags regardless of the revision level, since we
748 * previously didn't change the revision level when setting the flags,
749 * so there is a chance incompat flags are set on a rev 0 filesystem.
750 */
751 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
752 if (features) {
753 printk("EXT2-fs: %s: couldn't mount because of "
754 "unsupported optional features (%x).\n",
755 sb->s_id, le32_to_cpu(features));
756 goto failed_mount;
757 }
758 if (!(sb->s_flags & MS_RDONLY) &&
759 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
760 printk("EXT2-fs: %s: couldn't mount RDWR because of "
761 "unsupported optional features (%x).\n",
762 sb->s_id, le32_to_cpu(features));
763 goto failed_mount;
764 }
765
766 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
767
768 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
769 (sb->s_blocksize != blocksize))) {
770 if (!silent)
771 printk("XIP: Unsupported blocksize\n");
772 goto failed_mount;
773 }
774
775 /* If the blocksize doesn't match, re-read the thing.. */
776 if (sb->s_blocksize != blocksize) {
777 brelse(bh);
778
779 if (!sb_set_blocksize(sb, blocksize)) {
780 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
781 goto failed_sbi;
782 }
783
784 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
785 offset = (sb_block*BLOCK_SIZE) % blocksize;
786 bh = sb_bread(sb, logic_sb_block);
787 if(!bh) {
788 printk("EXT2-fs: Couldn't read superblock on "
789 "2nd try.\n");
790 goto failed_sbi;
791 }
792 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
793 sbi->s_es = es;
794 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
795 printk ("EXT2-fs: Magic mismatch, very weird !\n");
796 goto failed_mount;
797 }
798 }
799
800 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
801
802 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
803 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
804 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
805 } else {
806 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
807 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
808 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
809 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
810 (sbi->s_inode_size > blocksize)) {
811 printk ("EXT2-fs: unsupported inode size: %d\n",
812 sbi->s_inode_size);
813 goto failed_mount;
814 }
815 }
816
817 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
818 le32_to_cpu(es->s_log_frag_size);
819 if (sbi->s_frag_size == 0)
820 goto cantfind_ext2;
821 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
822
823 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
824 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
825 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
826
827 if (EXT2_INODE_SIZE(sb) == 0)
828 goto cantfind_ext2;
829 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
830 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
831 goto cantfind_ext2;
832 sbi->s_itb_per_group = sbi->s_inodes_per_group /
833 sbi->s_inodes_per_block;
834 sbi->s_desc_per_block = sb->s_blocksize /
835 sizeof (struct ext2_group_desc);
836 sbi->s_sbh = bh;
837 sbi->s_mount_state = le16_to_cpu(es->s_state);
838 sbi->s_addr_per_block_bits =
839 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
840 sbi->s_desc_per_block_bits =
841 ilog2 (EXT2_DESC_PER_BLOCK(sb));
842
843 if (sb->s_magic != EXT2_SUPER_MAGIC)
844 goto cantfind_ext2;
845
846 if (sb->s_blocksize != bh->b_size) {
847 if (!silent)
848 printk ("VFS: Unsupported blocksize on dev "
849 "%s.\n", sb->s_id);
850 goto failed_mount;
851 }
852
853 if (sb->s_blocksize != sbi->s_frag_size) {
854 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
855 sbi->s_frag_size, sb->s_blocksize);
856 goto failed_mount;
857 }
858
859 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
860 printk ("EXT2-fs: #blocks per group too big: %lu\n",
861 sbi->s_blocks_per_group);
862 goto failed_mount;
863 }
864 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
865 printk ("EXT2-fs: #fragments per group too big: %lu\n",
866 sbi->s_frags_per_group);
867 goto failed_mount;
868 }
869 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
870 printk ("EXT2-fs: #inodes per group too big: %lu\n",
871 sbi->s_inodes_per_group);
872 goto failed_mount;
873 }
874
875 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
876 goto cantfind_ext2;
877 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
878 le32_to_cpu(es->s_first_data_block) - 1)
879 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
880 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
881 EXT2_DESC_PER_BLOCK(sb);
882 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
883 if (sbi->s_group_desc == NULL) {
884 printk ("EXT2-fs: not enough memory\n");
885 goto failed_mount;
886 }
887 bgl_lock_init(&sbi->s_blockgroup_lock);
888 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
889 GFP_KERNEL);
890 if (!sbi->s_debts) {
891 printk ("EXT2-fs: not enough memory\n");
892 goto failed_mount_group_desc;
893 }
894 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
895 for (i = 0; i < db_count; i++) {
896 block = descriptor_loc(sb, logic_sb_block, i);
897 sbi->s_group_desc[i] = sb_bread(sb, block);
898 if (!sbi->s_group_desc[i]) {
899 for (j = 0; j < i; j++)
900 brelse (sbi->s_group_desc[j]);
901 printk ("EXT2-fs: unable to read group descriptors\n");
902 goto failed_mount_group_desc;
903 }
904 }
905 if (!ext2_check_descriptors (sb)) {
906 printk ("EXT2-fs: group descriptors corrupted!\n");
907 goto failed_mount2;
908 }
909 sbi->s_gdb_count = db_count;
910 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
911 spin_lock_init(&sbi->s_next_gen_lock);
912
913 percpu_counter_init(&sbi->s_freeblocks_counter,
914 ext2_count_free_blocks(sb));
915 percpu_counter_init(&sbi->s_freeinodes_counter,
916 ext2_count_free_inodes(sb));
917 percpu_counter_init(&sbi->s_dirs_counter,
918 ext2_count_dirs(sb));
919 /*
920 * set up enough so that it can read an inode
921 */
922 sb->s_op = &ext2_sops;
923 sb->s_export_op = &ext2_export_ops;
924 sb->s_xattr = ext2_xattr_handlers;
925 root = iget(sb, EXT2_ROOT_INO);
926 sb->s_root = d_alloc_root(root);
927 if (!sb->s_root) {
928 iput(root);
929 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
930 goto failed_mount3;
931 }
932 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
933 dput(sb->s_root);
934 sb->s_root = NULL;
935 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
936 goto failed_mount3;
937 }
938 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
939 ext2_warning(sb, __FUNCTION__,
940 "mounting ext3 filesystem as ext2");
941 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
942 return 0;
943
944 cantfind_ext2:
945 if (!silent)
946 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
947 sb->s_id);
948 goto failed_mount;
949 failed_mount3:
950 percpu_counter_destroy(&sbi->s_freeblocks_counter);
951 percpu_counter_destroy(&sbi->s_freeinodes_counter);
952 percpu_counter_destroy(&sbi->s_dirs_counter);
953 failed_mount2:
954 for (i = 0; i < db_count; i++)
955 brelse(sbi->s_group_desc[i]);
956 failed_mount_group_desc:
957 kfree(sbi->s_group_desc);
958 kfree(sbi->s_debts);
959 failed_mount:
960 brelse(bh);
961 failed_sbi:
962 sb->s_fs_info = NULL;
963 kfree(sbi);
964 return -EINVAL;
965 }
966
967 static void ext2_commit_super (struct super_block * sb,
968 struct ext2_super_block * es)
969 {
970 es->s_wtime = cpu_to_le32(get_seconds());
971 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
972 sb->s_dirt = 0;
973 }
974
975 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
976 {
977 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
978 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
979 es->s_wtime = cpu_to_le32(get_seconds());
980 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
981 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
982 sb->s_dirt = 0;
983 }
984
985 /*
986 * In the second extended file system, it is not necessary to
987 * write the super block since we use a mapping of the
988 * disk super block in a buffer.
989 *
990 * However, this function is still used to set the fs valid
991 * flags to 0. We need to set this flag to 0 since the fs
992 * may have been checked while mounted and e2fsck may have
993 * set s_state to EXT2_VALID_FS after some corrections.
994 */
995
996 void ext2_write_super (struct super_block * sb)
997 {
998 struct ext2_super_block * es;
999 lock_kernel();
1000 if (!(sb->s_flags & MS_RDONLY)) {
1001 es = EXT2_SB(sb)->s_es;
1002
1003 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
1004 ext2_debug ("setting valid to 0\n");
1005 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
1006 ~EXT2_VALID_FS);
1007 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1008 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1009 es->s_mtime = cpu_to_le32(get_seconds());
1010 ext2_sync_super(sb, es);
1011 } else
1012 ext2_commit_super (sb, es);
1013 }
1014 sb->s_dirt = 0;
1015 unlock_kernel();
1016 }
1017
1018 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1019 {
1020 struct ext2_sb_info * sbi = EXT2_SB(sb);
1021 struct ext2_super_block * es;
1022 unsigned long old_mount_opt = sbi->s_mount_opt;
1023 struct ext2_mount_options old_opts;
1024 unsigned long old_sb_flags;
1025 int err;
1026
1027 /* Store the old options */
1028 old_sb_flags = sb->s_flags;
1029 old_opts.s_mount_opt = sbi->s_mount_opt;
1030 old_opts.s_resuid = sbi->s_resuid;
1031 old_opts.s_resgid = sbi->s_resgid;
1032
1033 /*
1034 * Allow the "check" option to be passed as a remount option.
1035 */
1036 if (!parse_options (data, sbi)) {
1037 err = -EINVAL;
1038 goto restore_opts;
1039 }
1040
1041 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1042 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1043
1044 es = sbi->s_es;
1045 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1046 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1047 invalidate_inodes(sb))
1048 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1049 "xip remain in cache (no functional problem)");
1050 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1051 return 0;
1052 if (*flags & MS_RDONLY) {
1053 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1054 !(sbi->s_mount_state & EXT2_VALID_FS))
1055 return 0;
1056 /*
1057 * OK, we are remounting a valid rw partition rdonly, so set
1058 * the rdonly flag and then mark the partition as valid again.
1059 */
1060 es->s_state = cpu_to_le16(sbi->s_mount_state);
1061 es->s_mtime = cpu_to_le32(get_seconds());
1062 } else {
1063 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1064 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1065 if (ret) {
1066 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1067 "unsupported optional features (%x).\n",
1068 sb->s_id, le32_to_cpu(ret));
1069 err = -EROFS;
1070 goto restore_opts;
1071 }
1072 /*
1073 * Mounting a RDONLY partition read-write, so reread and
1074 * store the current valid flag. (It may have been changed
1075 * by e2fsck since we originally mounted the partition.)
1076 */
1077 sbi->s_mount_state = le16_to_cpu(es->s_state);
1078 if (!ext2_setup_super (sb, es, 0))
1079 sb->s_flags &= ~MS_RDONLY;
1080 }
1081 ext2_sync_super(sb, es);
1082 return 0;
1083 restore_opts:
1084 sbi->s_mount_opt = old_opts.s_mount_opt;
1085 sbi->s_resuid = old_opts.s_resuid;
1086 sbi->s_resgid = old_opts.s_resgid;
1087 sb->s_flags = old_sb_flags;
1088 return err;
1089 }
1090
1091 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1092 {
1093 struct super_block *sb = dentry->d_sb;
1094 struct ext2_sb_info *sbi = EXT2_SB(sb);
1095 struct ext2_super_block *es = sbi->s_es;
1096 unsigned long overhead;
1097 int i;
1098 u64 fsid;
1099
1100 if (test_opt (sb, MINIX_DF))
1101 overhead = 0;
1102 else {
1103 /*
1104 * Compute the overhead (FS structures)
1105 */
1106
1107 /*
1108 * All of the blocks before first_data_block are
1109 * overhead
1110 */
1111 overhead = le32_to_cpu(es->s_first_data_block);
1112
1113 /*
1114 * Add the overhead attributed to the superblock and
1115 * block group descriptors. If the sparse superblocks
1116 * feature is turned on, then not all groups have this.
1117 */
1118 for (i = 0; i < sbi->s_groups_count; i++)
1119 overhead += ext2_bg_has_super(sb, i) +
1120 ext2_bg_num_gdb(sb, i);
1121
1122 /*
1123 * Every block group has an inode bitmap, a block
1124 * bitmap, and an inode table.
1125 */
1126 overhead += (sbi->s_groups_count *
1127 (2 + sbi->s_itb_per_group));
1128 }
1129
1130 buf->f_type = EXT2_SUPER_MAGIC;
1131 buf->f_bsize = sb->s_blocksize;
1132 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead;
1133 buf->f_bfree = ext2_count_free_blocks(sb);
1134 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1135 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1136 buf->f_bavail = 0;
1137 buf->f_files = le32_to_cpu(es->s_inodes_count);
1138 buf->f_ffree = ext2_count_free_inodes(sb);
1139 buf->f_namelen = EXT2_NAME_LEN;
1140 fsid = le64_to_cpup((void *)es->s_uuid) ^
1141 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1142 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1143 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1144 return 0;
1145 }
1146
1147 static int ext2_get_sb(struct file_system_type *fs_type,
1148 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1149 {
1150 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1151 }
1152
1153 #ifdef CONFIG_QUOTA
1154
1155 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1156 * acquiring the locks... As quota files are never truncated and quota code
1157 * itself serializes the operations (and noone else should touch the files)
1158 * we don't have to be afraid of races */
1159 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1160 size_t len, loff_t off)
1161 {
1162 struct inode *inode = sb_dqopt(sb)->files[type];
1163 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1164 int err = 0;
1165 int offset = off & (sb->s_blocksize - 1);
1166 int tocopy;
1167 size_t toread;
1168 struct buffer_head tmp_bh;
1169 struct buffer_head *bh;
1170 loff_t i_size = i_size_read(inode);
1171
1172 if (off > i_size)
1173 return 0;
1174 if (off+len > i_size)
1175 len = i_size-off;
1176 toread = len;
1177 while (toread > 0) {
1178 tocopy = sb->s_blocksize - offset < toread ?
1179 sb->s_blocksize - offset : toread;
1180
1181 tmp_bh.b_state = 0;
1182 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1183 if (err)
1184 return err;
1185 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1186 memset(data, 0, tocopy);
1187 else {
1188 bh = sb_bread(sb, tmp_bh.b_blocknr);
1189 if (!bh)
1190 return -EIO;
1191 memcpy(data, bh->b_data+offset, tocopy);
1192 brelse(bh);
1193 }
1194 offset = 0;
1195 toread -= tocopy;
1196 data += tocopy;
1197 blk++;
1198 }
1199 return len;
1200 }
1201
1202 /* Write to quotafile */
1203 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1204 const char *data, size_t len, loff_t off)
1205 {
1206 struct inode *inode = sb_dqopt(sb)->files[type];
1207 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1208 int err = 0;
1209 int offset = off & (sb->s_blocksize - 1);
1210 int tocopy;
1211 size_t towrite = len;
1212 struct buffer_head tmp_bh;
1213 struct buffer_head *bh;
1214
1215 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1216 while (towrite > 0) {
1217 tocopy = sb->s_blocksize - offset < towrite ?
1218 sb->s_blocksize - offset : towrite;
1219
1220 tmp_bh.b_state = 0;
1221 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1222 if (err)
1223 goto out;
1224 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1225 bh = sb_bread(sb, tmp_bh.b_blocknr);
1226 else
1227 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1228 if (!bh) {
1229 err = -EIO;
1230 goto out;
1231 }
1232 lock_buffer(bh);
1233 memcpy(bh->b_data+offset, data, tocopy);
1234 flush_dcache_page(bh->b_page);
1235 set_buffer_uptodate(bh);
1236 mark_buffer_dirty(bh);
1237 unlock_buffer(bh);
1238 brelse(bh);
1239 offset = 0;
1240 towrite -= tocopy;
1241 data += tocopy;
1242 blk++;
1243 }
1244 out:
1245 if (len == towrite)
1246 return err;
1247 if (inode->i_size < off+len-towrite)
1248 i_size_write(inode, off+len-towrite);
1249 inode->i_version++;
1250 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1251 mark_inode_dirty(inode);
1252 mutex_unlock(&inode->i_mutex);
1253 return len - towrite;
1254 }
1255
1256 #endif
1257
1258 static struct file_system_type ext2_fs_type = {
1259 .owner = THIS_MODULE,
1260 .name = "ext2",
1261 .get_sb = ext2_get_sb,
1262 .kill_sb = kill_block_super,
1263 .fs_flags = FS_REQUIRES_DEV,
1264 };
1265
1266 static int __init init_ext2_fs(void)
1267 {
1268 int err = init_ext2_xattr();
1269 if (err)
1270 return err;
1271 err = init_inodecache();
1272 if (err)
1273 goto out1;
1274 err = register_filesystem(&ext2_fs_type);
1275 if (err)
1276 goto out;
1277 return 0;
1278 out:
1279 destroy_inodecache();
1280 out1:
1281 exit_ext2_xattr();
1282 return err;
1283 }
1284
1285 static void __exit exit_ext2_fs(void)
1286 {
1287 unregister_filesystem(&ext2_fs_type);
1288 destroy_inodecache();
1289 exit_ext2_xattr();
1290 }
1291
1292 module_init(init_ext2_fs)
1293 module_exit(exit_ext2_fs)
Support for the Chinese Samsung S3C2440 based development boards