ia64/linux-2.6.18-xen.hg

view fs/affs/super.c @ 524:7f8b544237bf

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This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 /*
2 * linux/fs/affs/inode.c
3 *
4 * (c) 1996 Hans-Joachim Widmaier - Rewritten
5 *
6 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
7 *
8 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
9 *
10 * (C) 1991 Linus Torvalds - minix filesystem
11 */
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/statfs.h>
16 #include <linux/parser.h>
17 #include "affs.h"
19 extern struct timezone sys_tz;
21 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
22 static int affs_remount (struct super_block *sb, int *flags, char *data);
24 static void
25 affs_put_super(struct super_block *sb)
26 {
27 struct affs_sb_info *sbi = AFFS_SB(sb);
28 pr_debug("AFFS: put_super()\n");
30 if (!(sb->s_flags & MS_RDONLY)) {
31 AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->bm_flag = cpu_to_be32(1);
32 secs_to_datestamp(get_seconds(),
33 &AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->disk_change);
34 affs_fix_checksum(sb, sbi->s_root_bh);
35 mark_buffer_dirty(sbi->s_root_bh);
36 }
38 kfree(sbi->s_prefix);
39 affs_free_bitmap(sb);
40 affs_brelse(sbi->s_root_bh);
41 kfree(sbi);
42 sb->s_fs_info = NULL;
43 return;
44 }
46 static void
47 affs_write_super(struct super_block *sb)
48 {
49 int clean = 2;
50 struct affs_sb_info *sbi = AFFS_SB(sb);
52 if (!(sb->s_flags & MS_RDONLY)) {
53 // if (sbi->s_bitmap[i].bm_bh) {
54 // if (buffer_dirty(sbi->s_bitmap[i].bm_bh)) {
55 // clean = 0;
56 AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->bm_flag = cpu_to_be32(clean);
57 secs_to_datestamp(get_seconds(),
58 &AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->disk_change);
59 affs_fix_checksum(sb, sbi->s_root_bh);
60 mark_buffer_dirty(sbi->s_root_bh);
61 sb->s_dirt = !clean; /* redo until bitmap synced */
62 } else
63 sb->s_dirt = 0;
65 pr_debug("AFFS: write_super() at %lu, clean=%d\n", get_seconds(), clean);
66 }
68 static kmem_cache_t * affs_inode_cachep;
70 static struct inode *affs_alloc_inode(struct super_block *sb)
71 {
72 struct affs_inode_info *ei;
73 ei = (struct affs_inode_info *)kmem_cache_alloc(affs_inode_cachep, SLAB_KERNEL);
74 if (!ei)
75 return NULL;
76 ei->vfs_inode.i_version = 1;
77 return &ei->vfs_inode;
78 }
80 static void affs_destroy_inode(struct inode *inode)
81 {
82 kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
83 }
85 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
86 {
87 struct affs_inode_info *ei = (struct affs_inode_info *) foo;
89 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
90 SLAB_CTOR_CONSTRUCTOR) {
91 init_MUTEX(&ei->i_link_lock);
92 init_MUTEX(&ei->i_ext_lock);
93 inode_init_once(&ei->vfs_inode);
94 }
95 }
97 static int init_inodecache(void)
98 {
99 affs_inode_cachep = kmem_cache_create("affs_inode_cache",
100 sizeof(struct affs_inode_info),
101 0, (SLAB_RECLAIM_ACCOUNT|
102 SLAB_MEM_SPREAD),
103 init_once, NULL);
104 if (affs_inode_cachep == NULL)
105 return -ENOMEM;
106 return 0;
107 }
109 static void destroy_inodecache(void)
110 {
111 if (kmem_cache_destroy(affs_inode_cachep))
112 printk(KERN_INFO "affs_inode_cache: not all structures were freed\n");
113 }
115 static struct super_operations affs_sops = {
116 .alloc_inode = affs_alloc_inode,
117 .destroy_inode = affs_destroy_inode,
118 .read_inode = affs_read_inode,
119 .write_inode = affs_write_inode,
120 .put_inode = affs_put_inode,
121 .delete_inode = affs_delete_inode,
122 .clear_inode = affs_clear_inode,
123 .put_super = affs_put_super,
124 .write_super = affs_write_super,
125 .statfs = affs_statfs,
126 .remount_fs = affs_remount,
127 };
129 enum {
130 Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect,
131 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
132 Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
133 };
135 static match_table_t tokens = {
136 {Opt_bs, "bs=%u"},
137 {Opt_mode, "mode=%o"},
138 {Opt_mufs, "mufs"},
139 {Opt_prefix, "prefix=%s"},
140 {Opt_protect, "protect"},
141 {Opt_reserved, "reserved=%u"},
142 {Opt_root, "root=%u"},
143 {Opt_setgid, "setgid=%u"},
144 {Opt_setuid, "setuid=%u"},
145 {Opt_verbose, "verbose"},
146 {Opt_volume, "volume=%s"},
147 {Opt_ignore, "grpquota"},
148 {Opt_ignore, "noquota"},
149 {Opt_ignore, "quota"},
150 {Opt_ignore, "usrquota"},
151 {Opt_err, NULL},
152 };
154 static int
155 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root,
156 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
157 {
158 char *p;
159 substring_t args[MAX_OPT_ARGS];
161 /* Fill in defaults */
163 *uid = current->uid;
164 *gid = current->gid;
165 *reserved = 2;
166 *root = -1;
167 *blocksize = -1;
168 volume[0] = ':';
169 volume[1] = 0;
170 *mount_opts = 0;
171 if (!options)
172 return 1;
174 while ((p = strsep(&options, ",")) != NULL) {
175 int token, n, option;
176 if (!*p)
177 continue;
179 token = match_token(p, tokens, args);
180 switch (token) {
181 case Opt_bs:
182 if (match_int(&args[0], &n))
183 return -EINVAL;
184 if (n != 512 && n != 1024 && n != 2048
185 && n != 4096) {
186 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
187 return 0;
188 }
189 *blocksize = n;
190 break;
191 case Opt_mode:
192 if (match_octal(&args[0], &option))
193 return 1;
194 *mode = option & 0777;
195 *mount_opts |= SF_SETMODE;
196 break;
197 case Opt_mufs:
198 *mount_opts |= SF_MUFS;
199 break;
200 case Opt_prefix:
201 /* Free any previous prefix */
202 kfree(*prefix);
203 *prefix = NULL;
204 *prefix = match_strdup(&args[0]);
205 if (!*prefix)
206 return 0;
207 *mount_opts |= SF_PREFIX;
208 break;
209 case Opt_protect:
210 *mount_opts |= SF_IMMUTABLE;
211 break;
212 case Opt_reserved:
213 if (match_int(&args[0], reserved))
214 return 1;
215 break;
216 case Opt_root:
217 if (match_int(&args[0], root))
218 return 1;
219 break;
220 case Opt_setgid:
221 if (match_int(&args[0], &option))
222 return 1;
223 *gid = option;
224 *mount_opts |= SF_SETGID;
225 break;
226 case Opt_setuid:
227 if (match_int(&args[0], &option))
228 return -EINVAL;
229 *uid = option;
230 *mount_opts |= SF_SETUID;
231 break;
232 case Opt_verbose:
233 *mount_opts |= SF_VERBOSE;
234 break;
235 case Opt_volume: {
236 char *vol = match_strdup(&args[0]);
237 strlcpy(volume, vol, 32);
238 kfree(vol);
239 break;
240 }
241 case Opt_ignore:
242 /* Silently ignore the quota options */
243 break;
244 default:
245 printk("AFFS: Unrecognized mount option \"%s\" "
246 "or missing value\n", p);
247 return 0;
248 }
249 }
250 return 1;
251 }
253 /* This function definitely needs to be split up. Some fine day I'll
254 * hopefully have the guts to do so. Until then: sorry for the mess.
255 */
257 static int affs_fill_super(struct super_block *sb, void *data, int silent)
258 {
259 struct affs_sb_info *sbi;
260 struct buffer_head *root_bh = NULL;
261 struct buffer_head *boot_bh;
262 struct inode *root_inode = NULL;
263 s32 root_block;
264 int size, blocksize;
265 u32 chksum;
266 int num_bm;
267 int i, j;
268 s32 key;
269 uid_t uid;
270 gid_t gid;
271 int reserved;
272 unsigned long mount_flags;
273 int tmp_flags; /* fix remount prototype... */
274 u8 sig[4];
276 pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options");
278 sb->s_magic = AFFS_SUPER_MAGIC;
279 sb->s_op = &affs_sops;
280 sb->s_flags |= MS_NODIRATIME;
282 sbi = kmalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
283 if (!sbi)
284 return -ENOMEM;
285 sb->s_fs_info = sbi;
286 memset(sbi, 0, sizeof(*sbi));
287 init_MUTEX(&sbi->s_bmlock);
289 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
290 &blocksize,&sbi->s_prefix,
291 sbi->s_volume, &mount_flags)) {
292 printk(KERN_ERR "AFFS: Error parsing options\n");
293 return -EINVAL;
294 }
295 /* N.B. after this point s_prefix must be released */
297 sbi->s_flags = mount_flags;
298 sbi->s_mode = i;
299 sbi->s_uid = uid;
300 sbi->s_gid = gid;
301 sbi->s_reserved= reserved;
303 /* Get the size of the device in 512-byte blocks.
304 * If we later see that the partition uses bigger
305 * blocks, we will have to change it.
306 */
308 size = sb->s_bdev->bd_inode->i_size >> 9;
309 pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size);
311 affs_set_blocksize(sb, PAGE_SIZE);
312 /* Try to find root block. Its location depends on the block size. */
314 i = 512;
315 j = 4096;
316 if (blocksize > 0) {
317 i = j = blocksize;
318 size = size / (blocksize / 512);
319 }
320 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) {
321 sbi->s_root_block = root_block;
322 if (root_block < 0)
323 sbi->s_root_block = (reserved + size - 1) / 2;
324 pr_debug("AFFS: setting blocksize to %d\n", blocksize);
325 affs_set_blocksize(sb, blocksize);
326 sbi->s_partition_size = size;
328 /* The root block location that was calculated above is not
329 * correct if the partition size is an odd number of 512-
330 * byte blocks, which will be rounded down to a number of
331 * 1024-byte blocks, and if there were an even number of
332 * reserved blocks. Ideally, all partition checkers should
333 * report the real number of blocks of the real blocksize,
334 * but since this just cannot be done, we have to try to
335 * find the root block anyways. In the above case, it is one
336 * block behind the calculated one. So we check this one, too.
337 */
338 for (num_bm = 0; num_bm < 2; num_bm++) {
339 pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, "
340 "size=%d, reserved=%d\n",
341 sb->s_id,
342 sbi->s_root_block + num_bm,
343 blocksize, size, reserved);
344 root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
345 if (!root_bh)
346 continue;
347 if (!affs_checksum_block(sb, root_bh) &&
348 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
349 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
350 sbi->s_hashsize = blocksize / 4 - 56;
351 sbi->s_root_block += num_bm;
352 key = 1;
353 goto got_root;
354 }
355 affs_brelse(root_bh);
356 root_bh = NULL;
357 }
358 }
359 if (!silent)
360 printk(KERN_ERR "AFFS: No valid root block on device %s\n",
361 sb->s_id);
362 goto out_error;
364 /* N.B. after this point bh must be released */
365 got_root:
366 root_block = sbi->s_root_block;
368 /* Find out which kind of FS we have */
369 boot_bh = sb_bread(sb, 0);
370 if (!boot_bh) {
371 printk(KERN_ERR "AFFS: Cannot read boot block\n");
372 goto out_error;
373 }
374 memcpy(sig, boot_bh->b_data, 4);
375 brelse(boot_bh);
376 chksum = be32_to_cpu(*(__be32 *)sig);
378 /* Dircache filesystems are compatible with non-dircache ones
379 * when reading. As long as they aren't supported, writing is
380 * not recommended.
381 */
382 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
383 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) {
384 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n",
385 sb->s_id);
386 sb->s_flags |= MS_RDONLY;
387 }
388 switch (chksum) {
389 case MUFS_FS:
390 case MUFS_INTLFFS:
391 case MUFS_DCFFS:
392 sbi->s_flags |= SF_MUFS;
393 /* fall thru */
394 case FS_INTLFFS:
395 case FS_DCFFS:
396 sbi->s_flags |= SF_INTL;
397 break;
398 case MUFS_FFS:
399 sbi->s_flags |= SF_MUFS;
400 break;
401 case FS_FFS:
402 break;
403 case MUFS_OFS:
404 sbi->s_flags |= SF_MUFS;
405 /* fall thru */
406 case FS_OFS:
407 sbi->s_flags |= SF_OFS;
408 sb->s_flags |= MS_NOEXEC;
409 break;
410 case MUFS_DCOFS:
411 case MUFS_INTLOFS:
412 sbi->s_flags |= SF_MUFS;
413 case FS_DCOFS:
414 case FS_INTLOFS:
415 sbi->s_flags |= SF_INTL | SF_OFS;
416 sb->s_flags |= MS_NOEXEC;
417 break;
418 default:
419 printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n",
420 sb->s_id, chksum);
421 goto out_error;
422 }
424 if (mount_flags & SF_VERBOSE) {
425 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
426 printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
427 len > 31 ? 31 : len,
428 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
429 sig, sig[3] + '0', blocksize);
430 }
432 sb->s_flags |= MS_NODEV | MS_NOSUID;
434 sbi->s_data_blksize = sb->s_blocksize;
435 if (sbi->s_flags & SF_OFS)
436 sbi->s_data_blksize -= 24;
438 /* Keep super block in cache */
439 sbi->s_root_bh = root_bh;
440 /* N.B. after this point s_root_bh must be released */
442 tmp_flags = sb->s_flags;
443 if (affs_init_bitmap(sb, &tmp_flags))
444 goto out_error;
445 sb->s_flags = tmp_flags;
447 /* set up enough so that it can read an inode */
449 root_inode = iget(sb, root_block);
450 sb->s_root = d_alloc_root(root_inode);
451 if (!sb->s_root) {
452 printk(KERN_ERR "AFFS: Get root inode failed\n");
453 goto out_error;
454 }
455 sb->s_root->d_op = &affs_dentry_operations;
457 pr_debug("AFFS: s_flags=%lX\n",sb->s_flags);
458 return 0;
460 /*
461 * Begin the cascaded cleanup ...
462 */
463 out_error:
464 if (root_inode)
465 iput(root_inode);
466 kfree(sbi->s_bitmap);
467 affs_brelse(root_bh);
468 kfree(sbi->s_prefix);
469 kfree(sbi);
470 sb->s_fs_info = NULL;
471 return -EINVAL;
472 }
474 static int
475 affs_remount(struct super_block *sb, int *flags, char *data)
476 {
477 struct affs_sb_info *sbi = AFFS_SB(sb);
478 int blocksize;
479 uid_t uid;
480 gid_t gid;
481 int mode;
482 int reserved;
483 int root_block;
484 unsigned long mount_flags;
485 int res = 0;
487 pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data);
489 *flags |= MS_NODIRATIME;
491 if (!parse_options(data,&uid,&gid,&mode,&reserved,&root_block,
492 &blocksize,&sbi->s_prefix,sbi->s_volume,&mount_flags))
493 return -EINVAL;
494 sbi->s_flags = mount_flags;
495 sbi->s_mode = mode;
496 sbi->s_uid = uid;
497 sbi->s_gid = gid;
499 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
500 return 0;
501 if (*flags & MS_RDONLY) {
502 sb->s_dirt = 1;
503 while (sb->s_dirt)
504 affs_write_super(sb);
505 affs_free_bitmap(sb);
506 } else
507 res = affs_init_bitmap(sb, flags);
509 return res;
510 }
512 static int
513 affs_statfs(struct dentry *dentry, struct kstatfs *buf)
514 {
515 struct super_block *sb = dentry->d_sb;
516 int free;
518 pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size,
519 AFFS_SB(sb)->s_reserved);
521 free = affs_count_free_blocks(sb);
522 buf->f_type = AFFS_SUPER_MAGIC;
523 buf->f_bsize = sb->s_blocksize;
524 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
525 buf->f_bfree = free;
526 buf->f_bavail = free;
527 return 0;
528 }
530 static int affs_get_sb(struct file_system_type *fs_type,
531 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
532 {
533 return get_sb_bdev(fs_type, flags, dev_name, data, affs_fill_super,
534 mnt);
535 }
537 static struct file_system_type affs_fs_type = {
538 .owner = THIS_MODULE,
539 .name = "affs",
540 .get_sb = affs_get_sb,
541 .kill_sb = kill_block_super,
542 .fs_flags = FS_REQUIRES_DEV,
543 };
545 static int __init init_affs_fs(void)
546 {
547 int err = init_inodecache();
548 if (err)
549 goto out1;
550 err = register_filesystem(&affs_fs_type);
551 if (err)
552 goto out;
553 return 0;
554 out:
555 destroy_inodecache();
556 out1:
557 return err;
558 }
560 static void __exit exit_affs_fs(void)
561 {
562 unregister_filesystem(&affs_fs_type);
563 destroy_inodecache();
564 }
566 MODULE_DESCRIPTION("Amiga filesystem support for Linux");
567 MODULE_LICENSE("GPL");
569 module_init(init_affs_fs)
570 module_exit(exit_affs_fs)