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1da177e4 LT |
1 | /* |
2 | * linux/fs/ext2/super.c | |
3 | * | |
4 | * Copyright (C) 1992, 1993, 1994, 1995 | |
5 | * Remy Card (card@masi.ibp.fr) | |
6 | * Laboratoire MASI - Institut Blaise Pascal | |
7 | * Universite Pierre et Marie Curie (Paris VI) | |
8 | * | |
9 | * from | |
10 | * | |
11 | * linux/fs/minix/inode.c | |
12 | * | |
13 | * Copyright (C) 1991, 1992 Linus Torvalds | |
14 | * | |
15 | * Big-endian to little-endian byte-swapping/bitmaps by | |
16 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
17 | */ | |
18 | ||
19 | #include <linux/config.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/string.h> | |
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 <asm/uaccess.h> | |
31 | #include "ext2.h" | |
32 | #include "xattr.h" | |
33 | #include "acl.h" | |
34 | ||
35 | static void ext2_sync_super(struct super_block *sb, | |
36 | struct ext2_super_block *es); | |
37 | static int ext2_remount (struct super_block * sb, int * flags, char * data); | |
38 | static int ext2_statfs (struct super_block * sb, struct kstatfs * buf); | |
39 | ||
40 | void ext2_error (struct super_block * sb, const char * function, | |
41 | const char * fmt, ...) | |
42 | { | |
43 | va_list args; | |
44 | struct ext2_sb_info *sbi = EXT2_SB(sb); | |
45 | struct ext2_super_block *es = sbi->s_es; | |
46 | ||
47 | if (!(sb->s_flags & MS_RDONLY)) { | |
48 | sbi->s_mount_state |= EXT2_ERROR_FS; | |
49 | es->s_state = | |
50 | cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS); | |
51 | ext2_sync_super(sb, es); | |
52 | } | |
53 | ||
54 | va_start(args, fmt); | |
55 | printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function); | |
56 | vprintk(fmt, args); | |
57 | printk("\n"); | |
58 | va_end(args); | |
59 | ||
60 | if (test_opt(sb, ERRORS_PANIC)) | |
61 | panic("EXT2-fs panic from previous error\n"); | |
62 | if (test_opt(sb, ERRORS_RO)) { | |
63 | printk("Remounting filesystem read-only\n"); | |
64 | sb->s_flags |= MS_RDONLY; | |
65 | } | |
66 | } | |
67 | ||
68 | void ext2_warning (struct super_block * sb, const char * function, | |
69 | const char * fmt, ...) | |
70 | { | |
71 | va_list args; | |
72 | ||
73 | va_start(args, fmt); | |
74 | printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ", | |
75 | sb->s_id, function); | |
76 | vprintk(fmt, args); | |
77 | printk("\n"); | |
78 | va_end(args); | |
79 | } | |
80 | ||
81 | void ext2_update_dynamic_rev(struct super_block *sb) | |
82 | { | |
83 | struct ext2_super_block *es = EXT2_SB(sb)->s_es; | |
84 | ||
85 | if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) | |
86 | return; | |
87 | ||
88 | ext2_warning(sb, __FUNCTION__, | |
89 | "updating to rev %d because of new feature flag, " | |
90 | "running e2fsck is recommended", | |
91 | EXT2_DYNAMIC_REV); | |
92 | ||
93 | es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); | |
94 | es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); | |
95 | es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); | |
96 | /* leave es->s_feature_*compat flags alone */ | |
97 | /* es->s_uuid will be set by e2fsck if empty */ | |
98 | ||
99 | /* | |
100 | * The rest of the superblock fields should be zero, and if not it | |
101 | * means they are likely already in use, so leave them alone. We | |
102 | * can leave it up to e2fsck to clean up any inconsistencies there. | |
103 | */ | |
104 | } | |
105 | ||
106 | static void ext2_put_super (struct super_block * sb) | |
107 | { | |
108 | int db_count; | |
109 | int i; | |
110 | struct ext2_sb_info *sbi = EXT2_SB(sb); | |
111 | ||
112 | ext2_xattr_put_super(sb); | |
113 | if (!(sb->s_flags & MS_RDONLY)) { | |
114 | struct ext2_super_block *es = sbi->s_es; | |
115 | ||
116 | es->s_state = cpu_to_le16(sbi->s_mount_state); | |
117 | ext2_sync_super(sb, es); | |
118 | } | |
119 | db_count = sbi->s_gdb_count; | |
120 | for (i = 0; i < db_count; i++) | |
121 | if (sbi->s_group_desc[i]) | |
122 | brelse (sbi->s_group_desc[i]); | |
123 | kfree(sbi->s_group_desc); | |
124 | kfree(sbi->s_debts); | |
125 | percpu_counter_destroy(&sbi->s_freeblocks_counter); | |
126 | percpu_counter_destroy(&sbi->s_freeinodes_counter); | |
127 | percpu_counter_destroy(&sbi->s_dirs_counter); | |
128 | brelse (sbi->s_sbh); | |
129 | sb->s_fs_info = NULL; | |
130 | kfree(sbi); | |
131 | ||
132 | return; | |
133 | } | |
134 | ||
135 | static kmem_cache_t * ext2_inode_cachep; | |
136 | ||
137 | static struct inode *ext2_alloc_inode(struct super_block *sb) | |
138 | { | |
139 | struct ext2_inode_info *ei; | |
140 | ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, SLAB_KERNEL); | |
141 | if (!ei) | |
142 | return NULL; | |
143 | #ifdef CONFIG_EXT2_FS_POSIX_ACL | |
144 | ei->i_acl = EXT2_ACL_NOT_CACHED; | |
145 | ei->i_default_acl = EXT2_ACL_NOT_CACHED; | |
146 | #endif | |
147 | ei->vfs_inode.i_version = 1; | |
148 | return &ei->vfs_inode; | |
149 | } | |
150 | ||
151 | static void ext2_destroy_inode(struct inode *inode) | |
152 | { | |
153 | kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); | |
154 | } | |
155 | ||
156 | static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) | |
157 | { | |
158 | struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; | |
159 | ||
160 | if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == | |
161 | SLAB_CTOR_CONSTRUCTOR) { | |
162 | rwlock_init(&ei->i_meta_lock); | |
163 | #ifdef CONFIG_EXT2_FS_XATTR | |
164 | init_rwsem(&ei->xattr_sem); | |
165 | #endif | |
166 | inode_init_once(&ei->vfs_inode); | |
167 | } | |
168 | } | |
169 | ||
170 | static int init_inodecache(void) | |
171 | { | |
172 | ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", | |
173 | sizeof(struct ext2_inode_info), | |
174 | 0, SLAB_RECLAIM_ACCOUNT, | |
175 | init_once, NULL); | |
176 | if (ext2_inode_cachep == NULL) | |
177 | return -ENOMEM; | |
178 | return 0; | |
179 | } | |
180 | ||
181 | static void destroy_inodecache(void) | |
182 | { | |
183 | if (kmem_cache_destroy(ext2_inode_cachep)) | |
184 | printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n"); | |
185 | } | |
186 | ||
187 | static void ext2_clear_inode(struct inode *inode) | |
188 | { | |
189 | #ifdef CONFIG_EXT2_FS_POSIX_ACL | |
190 | struct ext2_inode_info *ei = EXT2_I(inode); | |
191 | ||
192 | if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { | |
193 | posix_acl_release(ei->i_acl); | |
194 | ei->i_acl = EXT2_ACL_NOT_CACHED; | |
195 | } | |
196 | if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { | |
197 | posix_acl_release(ei->i_default_acl); | |
198 | ei->i_default_acl = EXT2_ACL_NOT_CACHED; | |
199 | } | |
200 | #endif | |
201 | if (!is_bad_inode(inode)) | |
202 | ext2_discard_prealloc(inode); | |
203 | } | |
204 | ||
205 | ||
206 | #ifdef CONFIG_QUOTA | |
207 | static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); | |
208 | static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); | |
209 | #endif | |
210 | ||
211 | static struct super_operations ext2_sops = { | |
212 | .alloc_inode = ext2_alloc_inode, | |
213 | .destroy_inode = ext2_destroy_inode, | |
214 | .read_inode = ext2_read_inode, | |
215 | .write_inode = ext2_write_inode, | |
216 | .delete_inode = ext2_delete_inode, | |
217 | .put_super = ext2_put_super, | |
218 | .write_super = ext2_write_super, | |
219 | .statfs = ext2_statfs, | |
220 | .remount_fs = ext2_remount, | |
221 | .clear_inode = ext2_clear_inode, | |
222 | #ifdef CONFIG_QUOTA | |
223 | .quota_read = ext2_quota_read, | |
224 | .quota_write = ext2_quota_write, | |
225 | #endif | |
226 | }; | |
227 | ||
228 | /* Yes, most of these are left as NULL!! | |
229 | * A NULL value implies the default, which works with ext2-like file | |
230 | * systems, but can be improved upon. | |
231 | * Currently only get_parent is required. | |
232 | */ | |
233 | struct dentry *ext2_get_parent(struct dentry *child); | |
234 | static struct export_operations ext2_export_ops = { | |
235 | .get_parent = ext2_get_parent, | |
236 | }; | |
237 | ||
238 | static unsigned long get_sb_block(void **data) | |
239 | { | |
240 | unsigned long sb_block; | |
241 | char *options = (char *) *data; | |
242 | ||
243 | if (!options || strncmp(options, "sb=", 3) != 0) | |
244 | return 1; /* Default location */ | |
245 | options += 3; | |
246 | sb_block = simple_strtoul(options, &options, 0); | |
247 | if (*options && *options != ',') { | |
248 | printk("EXT2-fs: Invalid sb specification: %s\n", | |
249 | (char *) *data); | |
250 | return 1; | |
251 | } | |
252 | if (*options == ',') | |
253 | options++; | |
254 | *data = (void *) options; | |
255 | return sb_block; | |
256 | } | |
257 | ||
258 | enum { | |
259 | Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, | |
260 | Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro, | |
261 | Opt_nouid32, Opt_check, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov, Opt_nobh, | |
262 | Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl, | |
263 | Opt_ignore, Opt_err, | |
264 | }; | |
265 | ||
266 | static match_table_t tokens = { | |
267 | {Opt_bsd_df, "bsddf"}, | |
268 | {Opt_minix_df, "minixdf"}, | |
269 | {Opt_grpid, "grpid"}, | |
270 | {Opt_grpid, "bsdgroups"}, | |
271 | {Opt_nogrpid, "nogrpid"}, | |
272 | {Opt_nogrpid, "sysvgroups"}, | |
273 | {Opt_resgid, "resgid=%u"}, | |
274 | {Opt_resuid, "resuid=%u"}, | |
275 | {Opt_sb, "sb=%u"}, | |
276 | {Opt_err_cont, "errors=continue"}, | |
277 | {Opt_err_panic, "errors=panic"}, | |
278 | {Opt_err_ro, "errors=remount-ro"}, | |
279 | {Opt_nouid32, "nouid32"}, | |
280 | {Opt_nocheck, "check=none"}, | |
281 | {Opt_nocheck, "nocheck"}, | |
282 | {Opt_check, "check"}, | |
283 | {Opt_debug, "debug"}, | |
284 | {Opt_oldalloc, "oldalloc"}, | |
285 | {Opt_orlov, "orlov"}, | |
286 | {Opt_nobh, "nobh"}, | |
287 | {Opt_user_xattr, "user_xattr"}, | |
288 | {Opt_nouser_xattr, "nouser_xattr"}, | |
289 | {Opt_acl, "acl"}, | |
290 | {Opt_noacl, "noacl"}, | |
291 | {Opt_ignore, "grpquota"}, | |
292 | {Opt_ignore, "noquota"}, | |
293 | {Opt_ignore, "quota"}, | |
294 | {Opt_ignore, "usrquota"}, | |
295 | {Opt_err, NULL} | |
296 | }; | |
297 | ||
298 | static int parse_options (char * options, | |
299 | struct ext2_sb_info *sbi) | |
300 | { | |
301 | char * p; | |
302 | substring_t args[MAX_OPT_ARGS]; | |
303 | unsigned long kind = EXT2_MOUNT_ERRORS_CONT; | |
304 | int option; | |
305 | ||
306 | if (!options) | |
307 | return 1; | |
308 | ||
309 | while ((p = strsep (&options, ",")) != NULL) { | |
310 | int token; | |
311 | if (!*p) | |
312 | continue; | |
313 | ||
314 | token = match_token(p, tokens, args); | |
315 | switch (token) { | |
316 | case Opt_bsd_df: | |
317 | clear_opt (sbi->s_mount_opt, MINIX_DF); | |
318 | break; | |
319 | case Opt_minix_df: | |
320 | set_opt (sbi->s_mount_opt, MINIX_DF); | |
321 | break; | |
322 | case Opt_grpid: | |
323 | set_opt (sbi->s_mount_opt, GRPID); | |
324 | break; | |
325 | case Opt_nogrpid: | |
326 | clear_opt (sbi->s_mount_opt, GRPID); | |
327 | break; | |
328 | case Opt_resuid: | |
329 | if (match_int(&args[0], &option)) | |
330 | return 0; | |
331 | sbi->s_resuid = option; | |
332 | break; | |
333 | case Opt_resgid: | |
334 | if (match_int(&args[0], &option)) | |
335 | return 0; | |
336 | sbi->s_resgid = option; | |
337 | break; | |
338 | case Opt_sb: | |
339 | /* handled by get_sb_block() instead of here */ | |
340 | /* *sb_block = match_int(&args[0]); */ | |
341 | break; | |
342 | case Opt_err_panic: | |
343 | kind = EXT2_MOUNT_ERRORS_PANIC; | |
344 | break; | |
345 | case Opt_err_ro: | |
346 | kind = EXT2_MOUNT_ERRORS_RO; | |
347 | break; | |
348 | case Opt_err_cont: | |
349 | kind = EXT2_MOUNT_ERRORS_CONT; | |
350 | break; | |
351 | case Opt_nouid32: | |
352 | set_opt (sbi->s_mount_opt, NO_UID32); | |
353 | break; | |
354 | case Opt_check: | |
355 | #ifdef CONFIG_EXT2_CHECK | |
356 | set_opt (sbi->s_mount_opt, CHECK); | |
357 | #else | |
358 | printk("EXT2 Check option not supported\n"); | |
359 | #endif | |
360 | break; | |
361 | case Opt_nocheck: | |
362 | clear_opt (sbi->s_mount_opt, CHECK); | |
363 | break; | |
364 | case Opt_debug: | |
365 | set_opt (sbi->s_mount_opt, DEBUG); | |
366 | break; | |
367 | case Opt_oldalloc: | |
368 | set_opt (sbi->s_mount_opt, OLDALLOC); | |
369 | break; | |
370 | case Opt_orlov: | |
371 | clear_opt (sbi->s_mount_opt, OLDALLOC); | |
372 | break; | |
373 | case Opt_nobh: | |
374 | set_opt (sbi->s_mount_opt, NOBH); | |
375 | break; | |
376 | #ifdef CONFIG_EXT2_FS_XATTR | |
377 | case Opt_user_xattr: | |
378 | set_opt (sbi->s_mount_opt, XATTR_USER); | |
379 | break; | |
380 | case Opt_nouser_xattr: | |
381 | clear_opt (sbi->s_mount_opt, XATTR_USER); | |
382 | break; | |
383 | #else | |
384 | case Opt_user_xattr: | |
385 | case Opt_nouser_xattr: | |
386 | printk("EXT2 (no)user_xattr options not supported\n"); | |
387 | break; | |
388 | #endif | |
389 | #ifdef CONFIG_EXT2_FS_POSIX_ACL | |
390 | case Opt_acl: | |
391 | set_opt(sbi->s_mount_opt, POSIX_ACL); | |
392 | break; | |
393 | case Opt_noacl: | |
394 | clear_opt(sbi->s_mount_opt, POSIX_ACL); | |
395 | break; | |
396 | #else | |
397 | case Opt_acl: | |
398 | case Opt_noacl: | |
399 | printk("EXT2 (no)acl options not supported\n"); | |
400 | break; | |
401 | #endif | |
402 | case Opt_ignore: | |
403 | break; | |
404 | default: | |
405 | return 0; | |
406 | } | |
407 | } | |
408 | sbi->s_mount_opt |= kind; | |
409 | return 1; | |
410 | } | |
411 | ||
412 | static int ext2_setup_super (struct super_block * sb, | |
413 | struct ext2_super_block * es, | |
414 | int read_only) | |
415 | { | |
416 | int res = 0; | |
417 | struct ext2_sb_info *sbi = EXT2_SB(sb); | |
418 | ||
419 | if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { | |
420 | printk ("EXT2-fs warning: revision level too high, " | |
421 | "forcing read-only mode\n"); | |
422 | res = MS_RDONLY; | |
423 | } | |
424 | if (read_only) | |
425 | return res; | |
426 | if (!(sbi->s_mount_state & EXT2_VALID_FS)) | |
427 | printk ("EXT2-fs warning: mounting unchecked fs, " | |
428 | "running e2fsck is recommended\n"); | |
429 | else if ((sbi->s_mount_state & EXT2_ERROR_FS)) | |
430 | printk ("EXT2-fs warning: mounting fs with errors, " | |
431 | "running e2fsck is recommended\n"); | |
432 | else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && | |
433 | le16_to_cpu(es->s_mnt_count) >= | |
434 | (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) | |
435 | printk ("EXT2-fs warning: maximal mount count reached, " | |
436 | "running e2fsck is recommended\n"); | |
437 | else if (le32_to_cpu(es->s_checkinterval) && | |
438 | (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) | |
439 | printk ("EXT2-fs warning: checktime reached, " | |
440 | "running e2fsck is recommended\n"); | |
441 | if (!le16_to_cpu(es->s_max_mnt_count)) | |
442 | es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); | |
443 | es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); | |
444 | ext2_write_super(sb); | |
445 | if (test_opt (sb, DEBUG)) | |
446 | printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " | |
447 | "bpg=%lu, ipg=%lu, mo=%04lx]\n", | |
448 | EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, | |
449 | sbi->s_frag_size, | |
450 | sbi->s_groups_count, | |
451 | EXT2_BLOCKS_PER_GROUP(sb), | |
452 | EXT2_INODES_PER_GROUP(sb), | |
453 | sbi->s_mount_opt); | |
454 | #ifdef CONFIG_EXT2_CHECK | |
455 | if (test_opt (sb, CHECK)) { | |
456 | ext2_check_blocks_bitmap (sb); | |
457 | ext2_check_inodes_bitmap (sb); | |
458 | } | |
459 | #endif | |
460 | return res; | |
461 | } | |
462 | ||
463 | static int ext2_check_descriptors (struct super_block * sb) | |
464 | { | |
465 | int i; | |
466 | int desc_block = 0; | |
467 | struct ext2_sb_info *sbi = EXT2_SB(sb); | |
468 | unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block); | |
469 | struct ext2_group_desc * gdp = NULL; | |
470 | ||
471 | ext2_debug ("Checking group descriptors"); | |
472 | ||
473 | for (i = 0; i < sbi->s_groups_count; i++) | |
474 | { | |
475 | if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) | |
476 | gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; | |
477 | if (le32_to_cpu(gdp->bg_block_bitmap) < block || | |
478 | le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb)) | |
479 | { | |
480 | ext2_error (sb, "ext2_check_descriptors", | |
481 | "Block bitmap for group %d" | |
482 | " not in group (block %lu)!", | |
483 | i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); | |
484 | return 0; | |
485 | } | |
486 | if (le32_to_cpu(gdp->bg_inode_bitmap) < block || | |
487 | le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb)) | |
488 | { | |
489 | ext2_error (sb, "ext2_check_descriptors", | |
490 | "Inode bitmap for group %d" | |
491 | " not in group (block %lu)!", | |
492 | i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); | |
493 | return 0; | |
494 | } | |
495 | if (le32_to_cpu(gdp->bg_inode_table) < block || | |
496 | le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >= | |
497 | block + EXT2_BLOCKS_PER_GROUP(sb)) | |
498 | { | |
499 | ext2_error (sb, "ext2_check_descriptors", | |
500 | "Inode table for group %d" | |
501 | " not in group (block %lu)!", | |
502 | i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); | |
503 | return 0; | |
504 | } | |
505 | block += EXT2_BLOCKS_PER_GROUP(sb); | |
506 | gdp++; | |
507 | } | |
508 | return 1; | |
509 | } | |
510 | ||
511 | #define log2(n) ffz(~(n)) | |
512 | ||
513 | /* | |
514 | * Maximal file size. There is a direct, and {,double-,triple-}indirect | |
515 | * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. | |
516 | * We need to be 1 filesystem block less than the 2^32 sector limit. | |
517 | */ | |
518 | static loff_t ext2_max_size(int bits) | |
519 | { | |
520 | loff_t res = EXT2_NDIR_BLOCKS; | |
521 | /* This constant is calculated to be the largest file size for a | |
522 | * dense, 4k-blocksize file such that the total number of | |
523 | * sectors in the file, including data and all indirect blocks, | |
524 | * does not exceed 2^32. */ | |
525 | const loff_t upper_limit = 0x1ff7fffd000LL; | |
526 | ||
527 | res += 1LL << (bits-2); | |
528 | res += 1LL << (2*(bits-2)); | |
529 | res += 1LL << (3*(bits-2)); | |
530 | res <<= bits; | |
531 | if (res > upper_limit) | |
532 | res = upper_limit; | |
533 | return res; | |
534 | } | |
535 | ||
536 | static unsigned long descriptor_loc(struct super_block *sb, | |
537 | unsigned long logic_sb_block, | |
538 | int nr) | |
539 | { | |
540 | struct ext2_sb_info *sbi = EXT2_SB(sb); | |
541 | unsigned long bg, first_data_block, first_meta_bg; | |
542 | int has_super = 0; | |
543 | ||
544 | first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); | |
545 | first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); | |
546 | ||
547 | if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || | |
548 | nr < first_meta_bg) | |
549 | return (logic_sb_block + nr + 1); | |
550 | bg = sbi->s_desc_per_block * nr; | |
551 | if (ext2_bg_has_super(sb, bg)) | |
552 | has_super = 1; | |
553 | return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); | |
554 | } | |
555 | ||
556 | static int ext2_fill_super(struct super_block *sb, void *data, int silent) | |
557 | { | |
558 | struct buffer_head * bh; | |
559 | struct ext2_sb_info * sbi; | |
560 | struct ext2_super_block * es; | |
561 | struct inode *root; | |
562 | unsigned long block; | |
563 | unsigned long sb_block = get_sb_block(&data); | |
564 | unsigned long logic_sb_block; | |
565 | unsigned long offset = 0; | |
566 | unsigned long def_mount_opts; | |
567 | int blocksize = BLOCK_SIZE; | |
568 | int db_count; | |
569 | int i, j; | |
570 | __le32 features; | |
571 | ||
572 | sbi = kmalloc(sizeof(*sbi), GFP_KERNEL); | |
573 | if (!sbi) | |
574 | return -ENOMEM; | |
575 | sb->s_fs_info = sbi; | |
576 | memset(sbi, 0, sizeof(*sbi)); | |
577 | ||
578 | /* | |
579 | * See what the current blocksize for the device is, and | |
580 | * use that as the blocksize. Otherwise (or if the blocksize | |
581 | * is smaller than the default) use the default. | |
582 | * This is important for devices that have a hardware | |
583 | * sectorsize that is larger than the default. | |
584 | */ | |
585 | blocksize = sb_min_blocksize(sb, BLOCK_SIZE); | |
586 | if (!blocksize) { | |
587 | printk ("EXT2-fs: unable to set blocksize\n"); | |
588 | goto failed_sbi; | |
589 | } | |
590 | ||
591 | /* | |
592 | * If the superblock doesn't start on a hardware sector boundary, | |
593 | * calculate the offset. | |
594 | */ | |
595 | if (blocksize != BLOCK_SIZE) { | |
596 | logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; | |
597 | offset = (sb_block*BLOCK_SIZE) % blocksize; | |
598 | } else { | |
599 | logic_sb_block = sb_block; | |
600 | } | |
601 | ||
602 | if (!(bh = sb_bread(sb, logic_sb_block))) { | |
603 | printk ("EXT2-fs: unable to read superblock\n"); | |
604 | goto failed_sbi; | |
605 | } | |
606 | /* | |
607 | * Note: s_es must be initialized as soon as possible because | |
608 | * some ext2 macro-instructions depend on its value | |
609 | */ | |
610 | es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); | |
611 | sbi->s_es = es; | |
612 | sb->s_magic = le16_to_cpu(es->s_magic); | |
613 | ||
614 | if (sb->s_magic != EXT2_SUPER_MAGIC) | |
615 | goto cantfind_ext2; | |
616 | ||
617 | /* Set defaults before we parse the mount options */ | |
618 | def_mount_opts = le32_to_cpu(es->s_default_mount_opts); | |
619 | if (def_mount_opts & EXT2_DEFM_DEBUG) | |
620 | set_opt(sbi->s_mount_opt, DEBUG); | |
621 | if (def_mount_opts & EXT2_DEFM_BSDGROUPS) | |
622 | set_opt(sbi->s_mount_opt, GRPID); | |
623 | if (def_mount_opts & EXT2_DEFM_UID16) | |
624 | set_opt(sbi->s_mount_opt, NO_UID32); | |
625 | if (def_mount_opts & EXT2_DEFM_XATTR_USER) | |
626 | set_opt(sbi->s_mount_opt, XATTR_USER); | |
627 | if (def_mount_opts & EXT2_DEFM_ACL) | |
628 | set_opt(sbi->s_mount_opt, POSIX_ACL); | |
629 | ||
630 | if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) | |
631 | set_opt(sbi->s_mount_opt, ERRORS_PANIC); | |
632 | else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) | |
633 | set_opt(sbi->s_mount_opt, ERRORS_RO); | |
634 | ||
635 | sbi->s_resuid = le16_to_cpu(es->s_def_resuid); | |
636 | sbi->s_resgid = le16_to_cpu(es->s_def_resgid); | |
637 | ||
638 | if (!parse_options ((char *) data, sbi)) | |
639 | goto failed_mount; | |
640 | ||
641 | sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | | |
642 | ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? | |
643 | MS_POSIXACL : 0); | |
644 | ||
645 | if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && | |
646 | (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || | |
647 | EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || | |
648 | EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) | |
649 | printk("EXT2-fs warning: feature flags set on rev 0 fs, " | |
650 | "running e2fsck is recommended\n"); | |
651 | /* | |
652 | * Check feature flags regardless of the revision level, since we | |
653 | * previously didn't change the revision level when setting the flags, | |
654 | * so there is a chance incompat flags are set on a rev 0 filesystem. | |
655 | */ | |
656 | features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); | |
657 | if (features) { | |
658 | printk("EXT2-fs: %s: couldn't mount because of " | |
659 | "unsupported optional features (%x).\n", | |
660 | sb->s_id, le32_to_cpu(features)); | |
661 | goto failed_mount; | |
662 | } | |
663 | if (!(sb->s_flags & MS_RDONLY) && | |
664 | (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ | |
665 | printk("EXT2-fs: %s: couldn't mount RDWR because of " | |
666 | "unsupported optional features (%x).\n", | |
667 | sb->s_id, le32_to_cpu(features)); | |
668 | goto failed_mount; | |
669 | } | |
670 | ||
671 | blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); | |
672 | ||
673 | /* If the blocksize doesn't match, re-read the thing.. */ | |
674 | if (sb->s_blocksize != blocksize) { | |
675 | brelse(bh); | |
676 | ||
677 | if (!sb_set_blocksize(sb, blocksize)) { | |
678 | printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); | |
679 | goto failed_sbi; | |
680 | } | |
681 | ||
682 | logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; | |
683 | offset = (sb_block*BLOCK_SIZE) % blocksize; | |
684 | bh = sb_bread(sb, logic_sb_block); | |
685 | if(!bh) { | |
686 | printk("EXT2-fs: Couldn't read superblock on " | |
687 | "2nd try.\n"); | |
688 | goto failed_sbi; | |
689 | } | |
690 | es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); | |
691 | sbi->s_es = es; | |
692 | if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { | |
693 | printk ("EXT2-fs: Magic mismatch, very weird !\n"); | |
694 | goto failed_mount; | |
695 | } | |
696 | } | |
697 | ||
698 | sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); | |
699 | ||
700 | if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { | |
701 | sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; | |
702 | sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; | |
703 | } else { | |
704 | sbi->s_inode_size = le16_to_cpu(es->s_inode_size); | |
705 | sbi->s_first_ino = le32_to_cpu(es->s_first_ino); | |
706 | if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || | |
707 | (sbi->s_inode_size & (sbi->s_inode_size - 1)) || | |
708 | (sbi->s_inode_size > blocksize)) { | |
709 | printk ("EXT2-fs: unsupported inode size: %d\n", | |
710 | sbi->s_inode_size); | |
711 | goto failed_mount; | |
712 | } | |
713 | } | |
714 | ||
715 | sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << | |
716 | le32_to_cpu(es->s_log_frag_size); | |
717 | if (sbi->s_frag_size == 0) | |
718 | goto cantfind_ext2; | |
719 | sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; | |
720 | ||
721 | sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); | |
722 | sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); | |
723 | sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); | |
724 | ||
725 | if (EXT2_INODE_SIZE(sb) == 0) | |
726 | goto cantfind_ext2; | |
727 | sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); | |
728 | if (sbi->s_inodes_per_block == 0) | |
729 | goto cantfind_ext2; | |
730 | sbi->s_itb_per_group = sbi->s_inodes_per_group / | |
731 | sbi->s_inodes_per_block; | |
732 | sbi->s_desc_per_block = sb->s_blocksize / | |
733 | sizeof (struct ext2_group_desc); | |
734 | sbi->s_sbh = bh; | |
735 | sbi->s_mount_state = le16_to_cpu(es->s_state); | |
736 | sbi->s_addr_per_block_bits = | |
737 | log2 (EXT2_ADDR_PER_BLOCK(sb)); | |
738 | sbi->s_desc_per_block_bits = | |
739 | log2 (EXT2_DESC_PER_BLOCK(sb)); | |
740 | ||
741 | if (sb->s_magic != EXT2_SUPER_MAGIC) | |
742 | goto cantfind_ext2; | |
743 | ||
744 | if (sb->s_blocksize != bh->b_size) { | |
745 | if (!silent) | |
746 | printk ("VFS: Unsupported blocksize on dev " | |
747 | "%s.\n", sb->s_id); | |
748 | goto failed_mount; | |
749 | } | |
750 | ||
751 | if (sb->s_blocksize != sbi->s_frag_size) { | |
752 | printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", | |
753 | sbi->s_frag_size, sb->s_blocksize); | |
754 | goto failed_mount; | |
755 | } | |
756 | ||
757 | if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { | |
758 | printk ("EXT2-fs: #blocks per group too big: %lu\n", | |
759 | sbi->s_blocks_per_group); | |
760 | goto failed_mount; | |
761 | } | |
762 | if (sbi->s_frags_per_group > sb->s_blocksize * 8) { | |
763 | printk ("EXT2-fs: #fragments per group too big: %lu\n", | |
764 | sbi->s_frags_per_group); | |
765 | goto failed_mount; | |
766 | } | |
767 | if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { | |
768 | printk ("EXT2-fs: #inodes per group too big: %lu\n", | |
769 | sbi->s_inodes_per_group); | |
770 | goto failed_mount; | |
771 | } | |
772 | ||
773 | if (EXT2_BLOCKS_PER_GROUP(sb) == 0) | |
774 | goto cantfind_ext2; | |
775 | sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) - | |
776 | le32_to_cpu(es->s_first_data_block) + | |
777 | EXT2_BLOCKS_PER_GROUP(sb) - 1) / | |
778 | EXT2_BLOCKS_PER_GROUP(sb); | |
779 | db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / | |
780 | EXT2_DESC_PER_BLOCK(sb); | |
781 | sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); | |
782 | if (sbi->s_group_desc == NULL) { | |
783 | printk ("EXT2-fs: not enough memory\n"); | |
784 | goto failed_mount; | |
785 | } | |
786 | percpu_counter_init(&sbi->s_freeblocks_counter); | |
787 | percpu_counter_init(&sbi->s_freeinodes_counter); | |
788 | percpu_counter_init(&sbi->s_dirs_counter); | |
789 | bgl_lock_init(&sbi->s_blockgroup_lock); | |
790 | sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), | |
791 | GFP_KERNEL); | |
792 | if (!sbi->s_debts) { | |
793 | printk ("EXT2-fs: not enough memory\n"); | |
794 | goto failed_mount_group_desc; | |
795 | } | |
796 | memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); | |
797 | for (i = 0; i < db_count; i++) { | |
798 | block = descriptor_loc(sb, logic_sb_block, i); | |
799 | sbi->s_group_desc[i] = sb_bread(sb, block); | |
800 | if (!sbi->s_group_desc[i]) { | |
801 | for (j = 0; j < i; j++) | |
802 | brelse (sbi->s_group_desc[j]); | |
803 | printk ("EXT2-fs: unable to read group descriptors\n"); | |
804 | goto failed_mount_group_desc; | |
805 | } | |
806 | } | |
807 | if (!ext2_check_descriptors (sb)) { | |
808 | printk ("EXT2-fs: group descriptors corrupted!\n"); | |
809 | db_count = i; | |
810 | goto failed_mount2; | |
811 | } | |
812 | sbi->s_gdb_count = db_count; | |
813 | get_random_bytes(&sbi->s_next_generation, sizeof(u32)); | |
814 | spin_lock_init(&sbi->s_next_gen_lock); | |
815 | /* | |
816 | * set up enough so that it can read an inode | |
817 | */ | |
818 | sb->s_op = &ext2_sops; | |
819 | sb->s_export_op = &ext2_export_ops; | |
820 | sb->s_xattr = ext2_xattr_handlers; | |
821 | root = iget(sb, EXT2_ROOT_INO); | |
822 | sb->s_root = d_alloc_root(root); | |
823 | if (!sb->s_root) { | |
824 | iput(root); | |
825 | printk(KERN_ERR "EXT2-fs: get root inode failed\n"); | |
826 | goto failed_mount2; | |
827 | } | |
828 | if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { | |
829 | dput(sb->s_root); | |
830 | sb->s_root = NULL; | |
831 | printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); | |
832 | goto failed_mount2; | |
833 | } | |
834 | if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) | |
835 | ext2_warning(sb, __FUNCTION__, | |
836 | "mounting ext3 filesystem as ext2\n"); | |
837 | ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); | |
838 | percpu_counter_mod(&sbi->s_freeblocks_counter, | |
839 | ext2_count_free_blocks(sb)); | |
840 | percpu_counter_mod(&sbi->s_freeinodes_counter, | |
841 | ext2_count_free_inodes(sb)); | |
842 | percpu_counter_mod(&sbi->s_dirs_counter, | |
843 | ext2_count_dirs(sb)); | |
844 | return 0; | |
845 | ||
846 | cantfind_ext2: | |
847 | if (!silent) | |
848 | printk("VFS: Can't find an ext2 filesystem on dev %s.\n", | |
849 | sb->s_id); | |
850 | goto failed_mount; | |
851 | ||
852 | failed_mount2: | |
853 | for (i = 0; i < db_count; i++) | |
854 | brelse(sbi->s_group_desc[i]); | |
855 | failed_mount_group_desc: | |
856 | kfree(sbi->s_group_desc); | |
857 | kfree(sbi->s_debts); | |
858 | failed_mount: | |
859 | brelse(bh); | |
860 | failed_sbi: | |
861 | sb->s_fs_info = NULL; | |
862 | kfree(sbi); | |
863 | return -EINVAL; | |
864 | } | |
865 | ||
866 | static void ext2_commit_super (struct super_block * sb, | |
867 | struct ext2_super_block * es) | |
868 | { | |
869 | es->s_wtime = cpu_to_le32(get_seconds()); | |
870 | mark_buffer_dirty(EXT2_SB(sb)->s_sbh); | |
871 | sb->s_dirt = 0; | |
872 | } | |
873 | ||
874 | static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) | |
875 | { | |
876 | es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); | |
877 | es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); | |
878 | es->s_wtime = cpu_to_le32(get_seconds()); | |
879 | mark_buffer_dirty(EXT2_SB(sb)->s_sbh); | |
880 | sync_dirty_buffer(EXT2_SB(sb)->s_sbh); | |
881 | sb->s_dirt = 0; | |
882 | } | |
883 | ||
884 | /* | |
885 | * In the second extended file system, it is not necessary to | |
886 | * write the super block since we use a mapping of the | |
887 | * disk super block in a buffer. | |
888 | * | |
889 | * However, this function is still used to set the fs valid | |
890 | * flags to 0. We need to set this flag to 0 since the fs | |
891 | * may have been checked while mounted and e2fsck may have | |
892 | * set s_state to EXT2_VALID_FS after some corrections. | |
893 | */ | |
894 | ||
895 | void ext2_write_super (struct super_block * sb) | |
896 | { | |
897 | struct ext2_super_block * es; | |
898 | lock_kernel(); | |
899 | if (!(sb->s_flags & MS_RDONLY)) { | |
900 | es = EXT2_SB(sb)->s_es; | |
901 | ||
902 | if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { | |
903 | ext2_debug ("setting valid to 0\n"); | |
904 | es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & | |
905 | ~EXT2_VALID_FS); | |
906 | es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); | |
907 | es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); | |
908 | es->s_mtime = cpu_to_le32(get_seconds()); | |
909 | ext2_sync_super(sb, es); | |
910 | } else | |
911 | ext2_commit_super (sb, es); | |
912 | } | |
913 | sb->s_dirt = 0; | |
914 | unlock_kernel(); | |
915 | } | |
916 | ||
917 | static int ext2_remount (struct super_block * sb, int * flags, char * data) | |
918 | { | |
919 | struct ext2_sb_info * sbi = EXT2_SB(sb); | |
920 | struct ext2_super_block * es; | |
921 | ||
922 | /* | |
923 | * Allow the "check" option to be passed as a remount option. | |
924 | */ | |
925 | if (!parse_options (data, sbi)) | |
926 | return -EINVAL; | |
927 | ||
928 | sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | | |
929 | ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); | |
930 | ||
931 | es = sbi->s_es; | |
932 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) | |
933 | return 0; | |
934 | if (*flags & MS_RDONLY) { | |
935 | if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || | |
936 | !(sbi->s_mount_state & EXT2_VALID_FS)) | |
937 | return 0; | |
938 | /* | |
939 | * OK, we are remounting a valid rw partition rdonly, so set | |
940 | * the rdonly flag and then mark the partition as valid again. | |
941 | */ | |
942 | es->s_state = cpu_to_le16(sbi->s_mount_state); | |
943 | es->s_mtime = cpu_to_le32(get_seconds()); | |
944 | } else { | |
945 | __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, | |
946 | ~EXT2_FEATURE_RO_COMPAT_SUPP); | |
947 | if (ret) { | |
948 | printk("EXT2-fs: %s: couldn't remount RDWR because of " | |
949 | "unsupported optional features (%x).\n", | |
950 | sb->s_id, le32_to_cpu(ret)); | |
951 | return -EROFS; | |
952 | } | |
953 | /* | |
954 | * Mounting a RDONLY partition read-write, so reread and | |
955 | * store the current valid flag. (It may have been changed | |
956 | * by e2fsck since we originally mounted the partition.) | |
957 | */ | |
958 | sbi->s_mount_state = le16_to_cpu(es->s_state); | |
959 | if (!ext2_setup_super (sb, es, 0)) | |
960 | sb->s_flags &= ~MS_RDONLY; | |
961 | } | |
962 | ext2_sync_super(sb, es); | |
963 | return 0; | |
964 | } | |
965 | ||
966 | static int ext2_statfs (struct super_block * sb, struct kstatfs * buf) | |
967 | { | |
968 | struct ext2_sb_info *sbi = EXT2_SB(sb); | |
969 | unsigned long overhead; | |
970 | int i; | |
971 | ||
972 | if (test_opt (sb, MINIX_DF)) | |
973 | overhead = 0; | |
974 | else { | |
975 | /* | |
976 | * Compute the overhead (FS structures) | |
977 | */ | |
978 | ||
979 | /* | |
980 | * All of the blocks before first_data_block are | |
981 | * overhead | |
982 | */ | |
983 | overhead = le32_to_cpu(sbi->s_es->s_first_data_block); | |
984 | ||
985 | /* | |
986 | * Add the overhead attributed to the superblock and | |
987 | * block group descriptors. If the sparse superblocks | |
988 | * feature is turned on, then not all groups have this. | |
989 | */ | |
990 | for (i = 0; i < sbi->s_groups_count; i++) | |
991 | overhead += ext2_bg_has_super(sb, i) + | |
992 | ext2_bg_num_gdb(sb, i); | |
993 | ||
994 | /* | |
995 | * Every block group has an inode bitmap, a block | |
996 | * bitmap, and an inode table. | |
997 | */ | |
998 | overhead += (sbi->s_groups_count * | |
999 | (2 + sbi->s_itb_per_group)); | |
1000 | } | |
1001 | ||
1002 | buf->f_type = EXT2_SUPER_MAGIC; | |
1003 | buf->f_bsize = sb->s_blocksize; | |
1004 | buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead; | |
1005 | buf->f_bfree = ext2_count_free_blocks(sb); | |
1006 | buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count); | |
1007 | if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count)) | |
1008 | buf->f_bavail = 0; | |
1009 | buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count); | |
1010 | buf->f_ffree = ext2_count_free_inodes (sb); | |
1011 | buf->f_namelen = EXT2_NAME_LEN; | |
1012 | return 0; | |
1013 | } | |
1014 | ||
1015 | static struct super_block *ext2_get_sb(struct file_system_type *fs_type, | |
1016 | int flags, const char *dev_name, void *data) | |
1017 | { | |
1018 | return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super); | |
1019 | } | |
1020 | ||
1021 | #ifdef CONFIG_QUOTA | |
1022 | ||
1023 | /* Read data from quotafile - avoid pagecache and such because we cannot afford | |
1024 | * acquiring the locks... As quota files are never truncated and quota code | |
1025 | * itself serializes the operations (and noone else should touch the files) | |
1026 | * we don't have to be afraid of races */ | |
1027 | static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, | |
1028 | size_t len, loff_t off) | |
1029 | { | |
1030 | struct inode *inode = sb_dqopt(sb)->files[type]; | |
1031 | sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); | |
1032 | int err = 0; | |
1033 | int offset = off & (sb->s_blocksize - 1); | |
1034 | int tocopy; | |
1035 | size_t toread; | |
1036 | struct buffer_head tmp_bh; | |
1037 | struct buffer_head *bh; | |
1038 | loff_t i_size = i_size_read(inode); | |
1039 | ||
1040 | if (off > i_size) | |
1041 | return 0; | |
1042 | if (off+len > i_size) | |
1043 | len = i_size-off; | |
1044 | toread = len; | |
1045 | while (toread > 0) { | |
1046 | tocopy = sb->s_blocksize - offset < toread ? | |
1047 | sb->s_blocksize - offset : toread; | |
1048 | ||
1049 | tmp_bh.b_state = 0; | |
1050 | err = ext2_get_block(inode, blk, &tmp_bh, 0); | |
1051 | if (err) | |
1052 | return err; | |
1053 | if (!buffer_mapped(&tmp_bh)) /* A hole? */ | |
1054 | memset(data, 0, tocopy); | |
1055 | else { | |
1056 | bh = sb_bread(sb, tmp_bh.b_blocknr); | |
1057 | if (!bh) | |
1058 | return -EIO; | |
1059 | memcpy(data, bh->b_data+offset, tocopy); | |
1060 | brelse(bh); | |
1061 | } | |
1062 | offset = 0; | |
1063 | toread -= tocopy; | |
1064 | data += tocopy; | |
1065 | blk++; | |
1066 | } | |
1067 | return len; | |
1068 | } | |
1069 | ||
1070 | /* Write to quotafile */ | |
1071 | static ssize_t ext2_quota_write(struct super_block *sb, int type, | |
1072 | const char *data, size_t len, loff_t off) | |
1073 | { | |
1074 | struct inode *inode = sb_dqopt(sb)->files[type]; | |
1075 | sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); | |
1076 | int err = 0; | |
1077 | int offset = off & (sb->s_blocksize - 1); | |
1078 | int tocopy; | |
1079 | size_t towrite = len; | |
1080 | struct buffer_head tmp_bh; | |
1081 | struct buffer_head *bh; | |
1082 | ||
1083 | down(&inode->i_sem); | |
1084 | while (towrite > 0) { | |
1085 | tocopy = sb->s_blocksize - offset < towrite ? | |
1086 | sb->s_blocksize - offset : towrite; | |
1087 | ||
1088 | tmp_bh.b_state = 0; | |
1089 | err = ext2_get_block(inode, blk, &tmp_bh, 1); | |
1090 | if (err) | |
1091 | goto out; | |
1092 | if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) | |
1093 | bh = sb_bread(sb, tmp_bh.b_blocknr); | |
1094 | else | |
1095 | bh = sb_getblk(sb, tmp_bh.b_blocknr); | |
1096 | if (!bh) { | |
1097 | err = -EIO; | |
1098 | goto out; | |
1099 | } | |
1100 | lock_buffer(bh); | |
1101 | memcpy(bh->b_data+offset, data, tocopy); | |
1102 | flush_dcache_page(bh->b_page); | |
1103 | set_buffer_uptodate(bh); | |
1104 | mark_buffer_dirty(bh); | |
1105 | unlock_buffer(bh); | |
1106 | brelse(bh); | |
1107 | offset = 0; | |
1108 | towrite -= tocopy; | |
1109 | data += tocopy; | |
1110 | blk++; | |
1111 | } | |
1112 | out: | |
1113 | if (len == towrite) | |
1114 | return err; | |
1115 | if (inode->i_size < off+len-towrite) | |
1116 | i_size_write(inode, off+len-towrite); | |
1117 | inode->i_version++; | |
1118 | inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
1119 | mark_inode_dirty(inode); | |
1120 | up(&inode->i_sem); | |
1121 | return len - towrite; | |
1122 | } | |
1123 | ||
1124 | #endif | |
1125 | ||
1126 | static struct file_system_type ext2_fs_type = { | |
1127 | .owner = THIS_MODULE, | |
1128 | .name = "ext2", | |
1129 | .get_sb = ext2_get_sb, | |
1130 | .kill_sb = kill_block_super, | |
1131 | .fs_flags = FS_REQUIRES_DEV, | |
1132 | }; | |
1133 | ||
1134 | static int __init init_ext2_fs(void) | |
1135 | { | |
1136 | int err = init_ext2_xattr(); | |
1137 | if (err) | |
1138 | return err; | |
1139 | err = init_inodecache(); | |
1140 | if (err) | |
1141 | goto out1; | |
1142 | err = register_filesystem(&ext2_fs_type); | |
1143 | if (err) | |
1144 | goto out; | |
1145 | return 0; | |
1146 | out: | |
1147 | destroy_inodecache(); | |
1148 | out1: | |
1149 | exit_ext2_xattr(); | |
1150 | return err; | |
1151 | } | |
1152 | ||
1153 | static void __exit exit_ext2_fs(void) | |
1154 | { | |
1155 | unregister_filesystem(&ext2_fs_type); | |
1156 | destroy_inodecache(); | |
1157 | exit_ext2_xattr(); | |
1158 | } | |
1159 | ||
1160 | module_init(init_ext2_fs) | |
1161 | module_exit(exit_ext2_fs) |