projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
[PATCH] Really ignore kmem_cache_destroy return value
[deliverable/linux.git] / fs / ext2 / super.c
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 kmem_cache_t * 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, 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
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, 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
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 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 unsigned long kind = EXT2_MOUNT_ERRORS_CONT;
368 int option;
369
370 if (!options)
371 return 1;
372
373 while ((p = strsep (&options, ",")) != NULL) {
374 int token;
375 if (!*p)
376 continue;
377
378 token = match_token(p, tokens, args);
379 switch (token) {
380 case Opt_bsd_df:
381 clear_opt (sbi->s_mount_opt, MINIX_DF);
382 break;
383 case Opt_minix_df:
384 set_opt (sbi->s_mount_opt, MINIX_DF);
385 break;
386 case Opt_grpid:
387 set_opt (sbi->s_mount_opt, GRPID);
388 break;
389 case Opt_nogrpid:
390 clear_opt (sbi->s_mount_opt, GRPID);
391 break;
392 case Opt_resuid:
393 if (match_int(&args[0], &option))
394 return 0;
395 sbi->s_resuid = option;
396 break;
397 case Opt_resgid:
398 if (match_int(&args[0], &option))
399 return 0;
400 sbi->s_resgid = option;
401 break;
402 case Opt_sb:
403 /* handled by get_sb_block() instead of here */
404 /* *sb_block = match_int(&args[0]); */
405 break;
406 case Opt_err_panic:
407 kind = EXT2_MOUNT_ERRORS_PANIC;
408 break;
409 case Opt_err_ro:
410 kind = EXT2_MOUNT_ERRORS_RO;
411 break;
412 case Opt_err_cont:
413 kind = EXT2_MOUNT_ERRORS_CONT;
414 break;
415 case Opt_nouid32:
416 set_opt (sbi->s_mount_opt, NO_UID32);
417 break;
418 case Opt_nocheck:
419 clear_opt (sbi->s_mount_opt, CHECK);
420 break;
421 case Opt_debug:
422 set_opt (sbi->s_mount_opt, DEBUG);
423 break;
424 case Opt_oldalloc:
425 set_opt (sbi->s_mount_opt, OLDALLOC);
426 break;
427 case Opt_orlov:
428 clear_opt (sbi->s_mount_opt, OLDALLOC);
429 break;
430 case Opt_nobh:
431 set_opt (sbi->s_mount_opt, NOBH);
432 break;
433 #ifdef CONFIG_EXT2_FS_XATTR
434 case Opt_user_xattr:
435 set_opt (sbi->s_mount_opt, XATTR_USER);
436 break;
437 case Opt_nouser_xattr:
438 clear_opt (sbi->s_mount_opt, XATTR_USER);
439 break;
440 #else
441 case Opt_user_xattr:
442 case Opt_nouser_xattr:
443 printk("EXT2 (no)user_xattr options not supported\n");
444 break;
445 #endif
446 #ifdef CONFIG_EXT2_FS_POSIX_ACL
447 case Opt_acl:
448 set_opt(sbi->s_mount_opt, POSIX_ACL);
449 break;
450 case Opt_noacl:
451 clear_opt(sbi->s_mount_opt, POSIX_ACL);
452 break;
453 #else
454 case Opt_acl:
455 case Opt_noacl:
456 printk("EXT2 (no)acl options not supported\n");
457 break;
458 #endif
459 case Opt_xip:
460 #ifdef CONFIG_EXT2_FS_XIP
461 set_opt (sbi->s_mount_opt, XIP);
462 #else
463 printk("EXT2 xip option not supported\n");
464 #endif
465 break;
466
467 #if defined(CONFIG_QUOTA)
468 case Opt_quota:
469 case Opt_usrquota:
470 set_opt(sbi->s_mount_opt, USRQUOTA);
471 break;
472
473 case Opt_grpquota:
474 set_opt(sbi->s_mount_opt, GRPQUOTA);
475 break;
476 #else
477 case Opt_quota:
478 case Opt_usrquota:
479 case Opt_grpquota:
480 printk(KERN_ERR
481 "EXT2-fs: quota operations not supported.\n");
482
483 break;
484 #endif
485
486 case Opt_ignore:
487 break;
488 default:
489 return 0;
490 }
491 }
492 sbi->s_mount_opt |= kind;
493 return 1;
494 }
495
496 static int ext2_setup_super (struct super_block * sb,
497 struct ext2_super_block * es,
498 int read_only)
499 {
500 int res = 0;
501 struct ext2_sb_info *sbi = EXT2_SB(sb);
502
503 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
504 printk ("EXT2-fs warning: revision level too high, "
505 "forcing read-only mode\n");
506 res = MS_RDONLY;
507 }
508 if (read_only)
509 return res;
510 if (!(sbi->s_mount_state & EXT2_VALID_FS))
511 printk ("EXT2-fs warning: mounting unchecked fs, "
512 "running e2fsck is recommended\n");
513 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
514 printk ("EXT2-fs warning: mounting fs with errors, "
515 "running e2fsck is recommended\n");
516 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
517 le16_to_cpu(es->s_mnt_count) >=
518 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
519 printk ("EXT2-fs warning: maximal mount count reached, "
520 "running e2fsck is recommended\n");
521 else if (le32_to_cpu(es->s_checkinterval) &&
522 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
523 printk ("EXT2-fs warning: checktime reached, "
524 "running e2fsck is recommended\n");
525 if (!le16_to_cpu(es->s_max_mnt_count))
526 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
527 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
528 ext2_write_super(sb);
529 if (test_opt (sb, DEBUG))
530 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
531 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
532 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
533 sbi->s_frag_size,
534 sbi->s_groups_count,
535 EXT2_BLOCKS_PER_GROUP(sb),
536 EXT2_INODES_PER_GROUP(sb),
537 sbi->s_mount_opt);
538 return res;
539 }
540
541 static int ext2_check_descriptors (struct super_block * sb)
542 {
543 int i;
544 int desc_block = 0;
545 struct ext2_sb_info *sbi = EXT2_SB(sb);
546 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
547 unsigned long last_block;
548 struct ext2_group_desc * gdp = NULL;
549
550 ext2_debug ("Checking group descriptors");
551
552 for (i = 0; i < sbi->s_groups_count; i++)
553 {
554 if (i == sbi->s_groups_count - 1)
555 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
556 else
557 last_block = first_block +
558 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
559
560 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
561 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
562 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
563 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
564 {
565 ext2_error (sb, "ext2_check_descriptors",
566 "Block bitmap for group %d"
567 " not in group (block %lu)!",
568 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
569 return 0;
570 }
571 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
572 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
573 {
574 ext2_error (sb, "ext2_check_descriptors",
575 "Inode bitmap for group %d"
576 " not in group (block %lu)!",
577 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
578 return 0;
579 }
580 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
581 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
582 last_block)
583 {
584 ext2_error (sb, "ext2_check_descriptors",
585 "Inode table for group %d"
586 " not in group (block %lu)!",
587 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
588 return 0;
589 }
590 first_block += EXT2_BLOCKS_PER_GROUP(sb);
591 gdp++;
592 }
593 return 1;
594 }
595
596 #define log2(n) ffz(~(n))
597
598 /*
599 * Maximal file size. There is a direct, and {,double-,triple-}indirect
600 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
601 * We need to be 1 filesystem block less than the 2^32 sector limit.
602 */
603 static loff_t ext2_max_size(int bits)
604 {
605 loff_t res = EXT2_NDIR_BLOCKS;
606 /* This constant is calculated to be the largest file size for a
607 * dense, 4k-blocksize file such that the total number of
608 * sectors in the file, including data and all indirect blocks,
609 * does not exceed 2^32. */
610 const loff_t upper_limit = 0x1ff7fffd000LL;
611
612 res += 1LL << (bits-2);
613 res += 1LL << (2*(bits-2));
614 res += 1LL << (3*(bits-2));
615 res <<= bits;
616 if (res > upper_limit)
617 res = upper_limit;
618 return res;
619 }
620
621 static unsigned long descriptor_loc(struct super_block *sb,
622 unsigned long logic_sb_block,
623 int nr)
624 {
625 struct ext2_sb_info *sbi = EXT2_SB(sb);
626 unsigned long bg, first_data_block, first_meta_bg;
627 int has_super = 0;
628
629 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
630 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
631
632 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
633 nr < first_meta_bg)
634 return (logic_sb_block + nr + 1);
635 bg = sbi->s_desc_per_block * nr;
636 if (ext2_bg_has_super(sb, bg))
637 has_super = 1;
638 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
639 }
640
641 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
642 {
643 struct buffer_head * bh;
644 struct ext2_sb_info * sbi;
645 struct ext2_super_block * es;
646 struct inode *root;
647 unsigned long block;
648 unsigned long sb_block = get_sb_block(&data);
649 unsigned long logic_sb_block;
650 unsigned long offset = 0;
651 unsigned long def_mount_opts;
652 int blocksize = BLOCK_SIZE;
653 int db_count;
654 int i, j;
655 __le32 features;
656
657 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
658 if (!sbi)
659 return -ENOMEM;
660 sb->s_fs_info = sbi;
661
662 /*
663 * See what the current blocksize for the device is, and
664 * use that as the blocksize. Otherwise (or if the blocksize
665 * is smaller than the default) use the default.
666 * This is important for devices that have a hardware
667 * sectorsize that is larger than the default.
668 */
669 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
670 if (!blocksize) {
671 printk ("EXT2-fs: unable to set blocksize\n");
672 goto failed_sbi;
673 }
674
675 /*
676 * If the superblock doesn't start on a hardware sector boundary,
677 * calculate the offset.
678 */
679 if (blocksize != BLOCK_SIZE) {
680 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
681 offset = (sb_block*BLOCK_SIZE) % blocksize;
682 } else {
683 logic_sb_block = sb_block;
684 }
685
686 if (!(bh = sb_bread(sb, logic_sb_block))) {
687 printk ("EXT2-fs: unable to read superblock\n");
688 goto failed_sbi;
689 }
690 /*
691 * Note: s_es must be initialized as soon as possible because
692 * some ext2 macro-instructions depend on its value
693 */
694 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
695 sbi->s_es = es;
696 sb->s_magic = le16_to_cpu(es->s_magic);
697
698 if (sb->s_magic != EXT2_SUPER_MAGIC)
699 goto cantfind_ext2;
700
701 /* Set defaults before we parse the mount options */
702 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
703 if (def_mount_opts & EXT2_DEFM_DEBUG)
704 set_opt(sbi->s_mount_opt, DEBUG);
705 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
706 set_opt(sbi->s_mount_opt, GRPID);
707 if (def_mount_opts & EXT2_DEFM_UID16)
708 set_opt(sbi->s_mount_opt, NO_UID32);
709 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
710 set_opt(sbi->s_mount_opt, XATTR_USER);
711 if (def_mount_opts & EXT2_DEFM_ACL)
712 set_opt(sbi->s_mount_opt, POSIX_ACL);
713
714 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
715 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
716 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
717 set_opt(sbi->s_mount_opt, ERRORS_RO);
718
719 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
720 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
721
722 if (!parse_options ((char *) data, sbi))
723 goto failed_mount;
724
725 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
726 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
727 MS_POSIXACL : 0);
728
729 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
730 EXT2_MOUNT_XIP if not */
731
732 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
733 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
734 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
735 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
736 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
737 "running e2fsck is recommended\n");
738 /*
739 * Check feature flags regardless of the revision level, since we
740 * previously didn't change the revision level when setting the flags,
741 * so there is a chance incompat flags are set on a rev 0 filesystem.
742 */
743 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
744 if (features) {
745 printk("EXT2-fs: %s: couldn't mount because of "
746 "unsupported optional features (%x).\n",
747 sb->s_id, le32_to_cpu(features));
748 goto failed_mount;
749 }
750 if (!(sb->s_flags & MS_RDONLY) &&
751 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
752 printk("EXT2-fs: %s: couldn't mount RDWR because of "
753 "unsupported optional features (%x).\n",
754 sb->s_id, le32_to_cpu(features));
755 goto failed_mount;
756 }
757
758 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
759
760 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
761 (sb->s_blocksize != blocksize))) {
762 if (!silent)
763 printk("XIP: Unsupported blocksize\n");
764 goto failed_mount;
765 }
766
767 /* If the blocksize doesn't match, re-read the thing.. */
768 if (sb->s_blocksize != blocksize) {
769 brelse(bh);
770
771 if (!sb_set_blocksize(sb, blocksize)) {
772 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
773 goto failed_sbi;
774 }
775
776 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
777 offset = (sb_block*BLOCK_SIZE) % blocksize;
778 bh = sb_bread(sb, logic_sb_block);
779 if(!bh) {
780 printk("EXT2-fs: Couldn't read superblock on "
781 "2nd try.\n");
782 goto failed_sbi;
783 }
784 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
785 sbi->s_es = es;
786 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
787 printk ("EXT2-fs: Magic mismatch, very weird !\n");
788 goto failed_mount;
789 }
790 }
791
792 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
793
794 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
795 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
796 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
797 } else {
798 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
799 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
800 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
801 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
802 (sbi->s_inode_size > blocksize)) {
803 printk ("EXT2-fs: unsupported inode size: %d\n",
804 sbi->s_inode_size);
805 goto failed_mount;
806 }
807 }
808
809 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
810 le32_to_cpu(es->s_log_frag_size);
811 if (sbi->s_frag_size == 0)
812 goto cantfind_ext2;
813 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
814
815 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
816 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
817 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
818
819 if (EXT2_INODE_SIZE(sb) == 0)
820 goto cantfind_ext2;
821 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
822 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
823 goto cantfind_ext2;
824 sbi->s_itb_per_group = sbi->s_inodes_per_group /
825 sbi->s_inodes_per_block;
826 sbi->s_desc_per_block = sb->s_blocksize /
827 sizeof (struct ext2_group_desc);
828 sbi->s_sbh = bh;
829 sbi->s_mount_state = le16_to_cpu(es->s_state);
830 sbi->s_addr_per_block_bits =
831 log2 (EXT2_ADDR_PER_BLOCK(sb));
832 sbi->s_desc_per_block_bits =
833 log2 (EXT2_DESC_PER_BLOCK(sb));
834
835 if (sb->s_magic != EXT2_SUPER_MAGIC)
836 goto cantfind_ext2;
837
838 if (sb->s_blocksize != bh->b_size) {
839 if (!silent)
840 printk ("VFS: Unsupported blocksize on dev "
841 "%s.\n", sb->s_id);
842 goto failed_mount;
843 }
844
845 if (sb->s_blocksize != sbi->s_frag_size) {
846 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
847 sbi->s_frag_size, sb->s_blocksize);
848 goto failed_mount;
849 }
850
851 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
852 printk ("EXT2-fs: #blocks per group too big: %lu\n",
853 sbi->s_blocks_per_group);
854 goto failed_mount;
855 }
856 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
857 printk ("EXT2-fs: #fragments per group too big: %lu\n",
858 sbi->s_frags_per_group);
859 goto failed_mount;
860 }
861 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
862 printk ("EXT2-fs: #inodes per group too big: %lu\n",
863 sbi->s_inodes_per_group);
864 goto failed_mount;
865 }
866
867 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
868 goto cantfind_ext2;
869 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
870 le32_to_cpu(es->s_first_data_block) - 1)
871 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
872 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
873 EXT2_DESC_PER_BLOCK(sb);
874 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
875 if (sbi->s_group_desc == NULL) {
876 printk ("EXT2-fs: not enough memory\n");
877 goto failed_mount;
878 }
879 bgl_lock_init(&sbi->s_blockgroup_lock);
880 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
881 GFP_KERNEL);
882 if (!sbi->s_debts) {
883 printk ("EXT2-fs: not enough memory\n");
884 goto failed_mount_group_desc;
885 }
886 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
887 for (i = 0; i < db_count; i++) {
888 block = descriptor_loc(sb, logic_sb_block, i);
889 sbi->s_group_desc[i] = sb_bread(sb, block);
890 if (!sbi->s_group_desc[i]) {
891 for (j = 0; j < i; j++)
892 brelse (sbi->s_group_desc[j]);
893 printk ("EXT2-fs: unable to read group descriptors\n");
894 goto failed_mount_group_desc;
895 }
896 }
897 if (!ext2_check_descriptors (sb)) {
898 printk ("EXT2-fs: group descriptors corrupted!\n");
899 goto failed_mount2;
900 }
901 sbi->s_gdb_count = db_count;
902 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
903 spin_lock_init(&sbi->s_next_gen_lock);
904
905 percpu_counter_init(&sbi->s_freeblocks_counter,
906 ext2_count_free_blocks(sb));
907 percpu_counter_init(&sbi->s_freeinodes_counter,
908 ext2_count_free_inodes(sb));
909 percpu_counter_init(&sbi->s_dirs_counter,
910 ext2_count_dirs(sb));
911 /*
912 * set up enough so that it can read an inode
913 */
914 sb->s_op = &ext2_sops;
915 sb->s_export_op = &ext2_export_ops;
916 sb->s_xattr = ext2_xattr_handlers;
917 root = iget(sb, EXT2_ROOT_INO);
918 sb->s_root = d_alloc_root(root);
919 if (!sb->s_root) {
920 iput(root);
921 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
922 goto failed_mount3;
923 }
924 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
925 dput(sb->s_root);
926 sb->s_root = NULL;
927 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
928 goto failed_mount3;
929 }
930 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
931 ext2_warning(sb, __FUNCTION__,
932 "mounting ext3 filesystem as ext2");
933 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
934 return 0;
935
936 cantfind_ext2:
937 if (!silent)
938 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
939 sb->s_id);
940 goto failed_mount;
941 failed_mount3:
942 percpu_counter_destroy(&sbi->s_freeblocks_counter);
943 percpu_counter_destroy(&sbi->s_freeinodes_counter);
944 percpu_counter_destroy(&sbi->s_dirs_counter);
945 failed_mount2:
946 for (i = 0; i < db_count; i++)
947 brelse(sbi->s_group_desc[i]);
948 failed_mount_group_desc:
949 kfree(sbi->s_group_desc);
950 kfree(sbi->s_debts);
951 failed_mount:
952 brelse(bh);
953 failed_sbi:
954 sb->s_fs_info = NULL;
955 kfree(sbi);
956 return -EINVAL;
957 }
958
959 static void ext2_commit_super (struct super_block * sb,
960 struct ext2_super_block * es)
961 {
962 es->s_wtime = cpu_to_le32(get_seconds());
963 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
964 sb->s_dirt = 0;
965 }
966
967 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
968 {
969 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
970 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
971 es->s_wtime = cpu_to_le32(get_seconds());
972 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
973 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
974 sb->s_dirt = 0;
975 }
976
977 /*
978 * In the second extended file system, it is not necessary to
979 * write the super block since we use a mapping of the
980 * disk super block in a buffer.
981 *
982 * However, this function is still used to set the fs valid
983 * flags to 0. We need to set this flag to 0 since the fs
984 * may have been checked while mounted and e2fsck may have
985 * set s_state to EXT2_VALID_FS after some corrections.
986 */
987
988 void ext2_write_super (struct super_block * sb)
989 {
990 struct ext2_super_block * es;
991 lock_kernel();
992 if (!(sb->s_flags & MS_RDONLY)) {
993 es = EXT2_SB(sb)->s_es;
994
995 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
996 ext2_debug ("setting valid to 0\n");
997 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
998 ~EXT2_VALID_FS);
999 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1000 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1001 es->s_mtime = cpu_to_le32(get_seconds());
1002 ext2_sync_super(sb, es);
1003 } else
1004 ext2_commit_super (sb, es);
1005 }
1006 sb->s_dirt = 0;
1007 unlock_kernel();
1008 }
1009
1010 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1011 {
1012 struct ext2_sb_info * sbi = EXT2_SB(sb);
1013 struct ext2_super_block * es;
1014 unsigned long old_mount_opt = sbi->s_mount_opt;
1015 struct ext2_mount_options old_opts;
1016 unsigned long old_sb_flags;
1017 int err;
1018
1019 /* Store the old options */
1020 old_sb_flags = sb->s_flags;
1021 old_opts.s_mount_opt = sbi->s_mount_opt;
1022 old_opts.s_resuid = sbi->s_resuid;
1023 old_opts.s_resgid = sbi->s_resgid;
1024
1025 /*
1026 * Allow the "check" option to be passed as a remount option.
1027 */
1028 if (!parse_options (data, sbi)) {
1029 err = -EINVAL;
1030 goto restore_opts;
1031 }
1032
1033 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1034 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1035
1036 es = sbi->s_es;
1037 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1038 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1039 invalidate_inodes(sb))
1040 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1041 "xip remain in cache (no functional problem)");
1042 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1043 return 0;
1044 if (*flags & MS_RDONLY) {
1045 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1046 !(sbi->s_mount_state & EXT2_VALID_FS))
1047 return 0;
1048 /*
1049 * OK, we are remounting a valid rw partition rdonly, so set
1050 * the rdonly flag and then mark the partition as valid again.
1051 */
1052 es->s_state = cpu_to_le16(sbi->s_mount_state);
1053 es->s_mtime = cpu_to_le32(get_seconds());
1054 } else {
1055 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1056 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1057 if (ret) {
1058 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1059 "unsupported optional features (%x).\n",
1060 sb->s_id, le32_to_cpu(ret));
1061 err = -EROFS;
1062 goto restore_opts;
1063 }
1064 /*
1065 * Mounting a RDONLY partition read-write, so reread and
1066 * store the current valid flag. (It may have been changed
1067 * by e2fsck since we originally mounted the partition.)
1068 */
1069 sbi->s_mount_state = le16_to_cpu(es->s_state);
1070 if (!ext2_setup_super (sb, es, 0))
1071 sb->s_flags &= ~MS_RDONLY;
1072 }
1073 ext2_sync_super(sb, es);
1074 return 0;
1075 restore_opts:
1076 sbi->s_mount_opt = old_opts.s_mount_opt;
1077 sbi->s_resuid = old_opts.s_resuid;
1078 sbi->s_resgid = old_opts.s_resgid;
1079 sb->s_flags = old_sb_flags;
1080 return err;
1081 }
1082
1083 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1084 {
1085 struct super_block *sb = dentry->d_sb;
1086 struct ext2_sb_info *sbi = EXT2_SB(sb);
1087 unsigned long overhead;
1088 int i;
1089
1090 if (test_opt (sb, MINIX_DF))
1091 overhead = 0;
1092 else {
1093 /*
1094 * Compute the overhead (FS structures)
1095 */
1096
1097 /*
1098 * All of the blocks before first_data_block are
1099 * overhead
1100 */
1101 overhead = le32_to_cpu(sbi->s_es->s_first_data_block);
1102
1103 /*
1104 * Add the overhead attributed to the superblock and
1105 * block group descriptors. If the sparse superblocks
1106 * feature is turned on, then not all groups have this.
1107 */
1108 for (i = 0; i < sbi->s_groups_count; i++)
1109 overhead += ext2_bg_has_super(sb, i) +
1110 ext2_bg_num_gdb(sb, i);
1111
1112 /*
1113 * Every block group has an inode bitmap, a block
1114 * bitmap, and an inode table.
1115 */
1116 overhead += (sbi->s_groups_count *
1117 (2 + sbi->s_itb_per_group));
1118 }
1119
1120 buf->f_type = EXT2_SUPER_MAGIC;
1121 buf->f_bsize = sb->s_blocksize;
1122 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead;
1123 buf->f_bfree = ext2_count_free_blocks(sb);
1124 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count);
1125 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count))
1126 buf->f_bavail = 0;
1127 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count);
1128 buf->f_ffree = ext2_count_free_inodes (sb);
1129 buf->f_namelen = EXT2_NAME_LEN;
1130 return 0;
1131 }
1132
1133 static int ext2_get_sb(struct file_system_type *fs_type,
1134 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1135 {
1136 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1137 }
1138
1139 #ifdef CONFIG_QUOTA
1140
1141 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1142 * acquiring the locks... As quota files are never truncated and quota code
1143 * itself serializes the operations (and noone else should touch the files)
1144 * we don't have to be afraid of races */
1145 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1146 size_t len, loff_t off)
1147 {
1148 struct inode *inode = sb_dqopt(sb)->files[type];
1149 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1150 int err = 0;
1151 int offset = off & (sb->s_blocksize - 1);
1152 int tocopy;
1153 size_t toread;
1154 struct buffer_head tmp_bh;
1155 struct buffer_head *bh;
1156 loff_t i_size = i_size_read(inode);
1157
1158 if (off > i_size)
1159 return 0;
1160 if (off+len > i_size)
1161 len = i_size-off;
1162 toread = len;
1163 while (toread > 0) {
1164 tocopy = sb->s_blocksize - offset < toread ?
1165 sb->s_blocksize - offset : toread;
1166
1167 tmp_bh.b_state = 0;
1168 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1169 if (err)
1170 return err;
1171 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1172 memset(data, 0, tocopy);
1173 else {
1174 bh = sb_bread(sb, tmp_bh.b_blocknr);
1175 if (!bh)
1176 return -EIO;
1177 memcpy(data, bh->b_data+offset, tocopy);
1178 brelse(bh);
1179 }
1180 offset = 0;
1181 toread -= tocopy;
1182 data += tocopy;
1183 blk++;
1184 }
1185 return len;
1186 }
1187
1188 /* Write to quotafile */
1189 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1190 const char *data, size_t len, loff_t off)
1191 {
1192 struct inode *inode = sb_dqopt(sb)->files[type];
1193 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1194 int err = 0;
1195 int offset = off & (sb->s_blocksize - 1);
1196 int tocopy;
1197 size_t towrite = len;
1198 struct buffer_head tmp_bh;
1199 struct buffer_head *bh;
1200
1201 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1202 while (towrite > 0) {
1203 tocopy = sb->s_blocksize - offset < towrite ?
1204 sb->s_blocksize - offset : towrite;
1205
1206 tmp_bh.b_state = 0;
1207 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1208 if (err)
1209 goto out;
1210 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1211 bh = sb_bread(sb, tmp_bh.b_blocknr);
1212 else
1213 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1214 if (!bh) {
1215 err = -EIO;
1216 goto out;
1217 }
1218 lock_buffer(bh);
1219 memcpy(bh->b_data+offset, data, tocopy);
1220 flush_dcache_page(bh->b_page);
1221 set_buffer_uptodate(bh);
1222 mark_buffer_dirty(bh);
1223 unlock_buffer(bh);
1224 brelse(bh);
1225 offset = 0;
1226 towrite -= tocopy;
1227 data += tocopy;
1228 blk++;
1229 }
1230 out:
1231 if (len == towrite)
1232 return err;
1233 if (inode->i_size < off+len-towrite)
1234 i_size_write(inode, off+len-towrite);
1235 inode->i_version++;
1236 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1237 mark_inode_dirty(inode);
1238 mutex_unlock(&inode->i_mutex);
1239 return len - towrite;
1240 }
1241
1242 #endif
1243
1244 static struct file_system_type ext2_fs_type = {
1245 .owner = THIS_MODULE,
1246 .name = "ext2",
1247 .get_sb = ext2_get_sb,
1248 .kill_sb = kill_block_super,
1249 .fs_flags = FS_REQUIRES_DEV,
1250 };
1251
1252 static int __init init_ext2_fs(void)
1253 {
1254 int err = init_ext2_xattr();
1255 if (err)
1256 return err;
1257 err = init_inodecache();
1258 if (err)
1259 goto out1;
1260 err = register_filesystem(&ext2_fs_type);
1261 if (err)
1262 goto out;
1263 return 0;
1264 out:
1265 destroy_inodecache();
1266 out1:
1267 exit_ext2_xattr();
1268 return err;
1269 }
1270
1271 static void __exit exit_ext2_fs(void)
1272 {
1273 unregister_filesystem(&ext2_fs_type);
1274 destroy_inodecache();
1275 exit_ext2_xattr();
1276 }
1277
1278 module_init(init_ext2_fs)
1279 module_exit(exit_ext2_fs)
Linux kernel - Deliverables
This page took 0.056257 seconds and 5 git commands to generate.