[PATCH] cpuset memory spread: slab cache filesystems
[linux-2.6.git] / fs / affs / super.c
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  */
12
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/statfs.h>
16 #include <linux/parser.h>
17 #include "affs.h"
18
19 extern struct timezone sys_tz;
20
21 static int affs_statfs(struct super_block *sb, struct kstatfs *buf);
22 static int affs_remount (struct super_block *sb, int *flags, char *data);
23
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");
29
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         }
37
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 }
45
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);
51
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;
64
65         pr_debug("AFFS: write_super() at %lu, clean=%d\n", get_seconds(), clean);
66 }
67
68 static kmem_cache_t * affs_inode_cachep;
69
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 }
79
80 static void affs_destroy_inode(struct inode *inode)
81 {
82         kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
83 }
84
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;
88
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 }
96
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|SLAB_MEM_SPREAD,
102                                              init_once, NULL);
103         if (affs_inode_cachep == NULL)
104                 return -ENOMEM;
105         return 0;
106 }
107
108 static void destroy_inodecache(void)
109 {
110         if (kmem_cache_destroy(affs_inode_cachep))
111                 printk(KERN_INFO "affs_inode_cache: not all structures were freed\n");
112 }
113
114 static struct super_operations affs_sops = {
115         .alloc_inode    = affs_alloc_inode,
116         .destroy_inode  = affs_destroy_inode,
117         .read_inode     = affs_read_inode,
118         .write_inode    = affs_write_inode,
119         .put_inode      = affs_put_inode,
120         .delete_inode   = affs_delete_inode,
121         .clear_inode    = affs_clear_inode,
122         .put_super      = affs_put_super,
123         .write_super    = affs_write_super,
124         .statfs         = affs_statfs,
125         .remount_fs     = affs_remount,
126 };
127
128 enum {
129         Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect,
130         Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
131         Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
132 };
133
134 static match_table_t tokens = {
135         {Opt_bs, "bs=%u"},
136         {Opt_mode, "mode=%o"},
137         {Opt_mufs, "mufs"},
138         {Opt_prefix, "prefix=%s"},
139         {Opt_protect, "protect"},
140         {Opt_reserved, "reserved=%u"},
141         {Opt_root, "root=%u"},
142         {Opt_setgid, "setgid=%u"},
143         {Opt_setuid, "setuid=%u"},
144         {Opt_verbose, "verbose"},
145         {Opt_volume, "volume=%s"},
146         {Opt_ignore, "grpquota"},
147         {Opt_ignore, "noquota"},
148         {Opt_ignore, "quota"},
149         {Opt_ignore, "usrquota"},
150         {Opt_err, NULL},
151 };
152
153 static int
154 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root,
155                 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
156 {
157         char *p;
158         substring_t args[MAX_OPT_ARGS];
159
160         /* Fill in defaults */
161
162         *uid        = current->uid;
163         *gid        = current->gid;
164         *reserved   = 2;
165         *root       = -1;
166         *blocksize  = -1;
167         volume[0]   = ':';
168         volume[1]   = 0;
169         *mount_opts = 0;
170         if (!options)
171                 return 1;
172
173         while ((p = strsep(&options, ",")) != NULL) {
174                 int token, n, option;
175                 if (!*p)
176                         continue;
177
178                 token = match_token(p, tokens, args);
179                 switch (token) {
180                 case Opt_bs:
181                         if (match_int(&args[0], &n))
182                                 return -EINVAL;
183                         if (n != 512 && n != 1024 && n != 2048
184                             && n != 4096) {
185                                 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
186                                 return 0;
187                         }
188                         *blocksize = n;
189                         break;
190                 case Opt_mode:
191                         if (match_octal(&args[0], &option))
192                                 return 1;
193                         *mode = option & 0777;
194                         *mount_opts |= SF_SETMODE;
195                         break;
196                 case Opt_mufs:
197                         *mount_opts |= SF_MUFS;
198                         break;
199                 case Opt_prefix:
200                         /* Free any previous prefix */
201                         kfree(*prefix);
202                         *prefix = NULL;
203                         *prefix = match_strdup(&args[0]);
204                         if (!*prefix)
205                                 return 0;
206                         *mount_opts |= SF_PREFIX;
207                         break;
208                 case Opt_protect:
209                         *mount_opts |= SF_IMMUTABLE;
210                         break;
211                 case Opt_reserved:
212                         if (match_int(&args[0], reserved))
213                                 return 1;
214                         break;
215                 case Opt_root:
216                         if (match_int(&args[0], root))
217                                 return 1;
218                         break;
219                 case Opt_setgid:
220                         if (match_int(&args[0], &option))
221                                 return 1;
222                         *gid = option;
223                         *mount_opts |= SF_SETGID;
224                         break;
225                 case Opt_setuid:
226                         if (match_int(&args[0], &option))
227                                 return -EINVAL;
228                         *uid = option;
229                         *mount_opts |= SF_SETUID;
230                         break;
231                 case Opt_verbose:
232                         *mount_opts |= SF_VERBOSE;
233                         break;
234                 case Opt_volume: {
235                         char *vol = match_strdup(&args[0]);
236                         strlcpy(volume, vol, 32);
237                         kfree(vol);
238                         break;
239                 }
240                 case Opt_ignore:
241                         /* Silently ignore the quota options */
242                         break;
243                 default:
244                         printk("AFFS: Unrecognized mount option \"%s\" "
245                                         "or missing value\n", p);
246                         return 0;
247                 }
248         }
249         return 1;
250 }
251
252 /* This function definitely needs to be split up. Some fine day I'll
253  * hopefully have the guts to do so. Until then: sorry for the mess.
254  */
255
256 static int affs_fill_super(struct super_block *sb, void *data, int silent)
257 {
258         struct affs_sb_info     *sbi;
259         struct buffer_head      *root_bh = NULL;
260         struct buffer_head      *boot_bh;
261         struct inode            *root_inode = NULL;
262         s32                      root_block;
263         int                      size, blocksize;
264         u32                      chksum;
265         int                      num_bm;
266         int                      i, j;
267         s32                      key;
268         uid_t                    uid;
269         gid_t                    gid;
270         int                      reserved;
271         unsigned long            mount_flags;
272         int                      tmp_flags;     /* fix remount prototype... */
273
274         pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options");
275
276         sb->s_magic             = AFFS_SUPER_MAGIC;
277         sb->s_op                = &affs_sops;
278         sb->s_flags |= MS_NODIRATIME;
279
280         sbi = kmalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
281         if (!sbi)
282                 return -ENOMEM;
283         sb->s_fs_info = sbi;
284         memset(sbi, 0, sizeof(*sbi));
285         init_MUTEX(&sbi->s_bmlock);
286
287         if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
288                                 &blocksize,&sbi->s_prefix,
289                                 sbi->s_volume, &mount_flags)) {
290                 printk(KERN_ERR "AFFS: Error parsing options\n");
291                 return -EINVAL;
292         }
293         /* N.B. after this point s_prefix must be released */
294
295         sbi->s_flags   = mount_flags;
296         sbi->s_mode    = i;
297         sbi->s_uid     = uid;
298         sbi->s_gid     = gid;
299         sbi->s_reserved= reserved;
300
301         /* Get the size of the device in 512-byte blocks.
302          * If we later see that the partition uses bigger
303          * blocks, we will have to change it.
304          */
305
306         size = sb->s_bdev->bd_inode->i_size >> 9;
307         pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size);
308
309         affs_set_blocksize(sb, PAGE_SIZE);
310         /* Try to find root block. Its location depends on the block size. */
311
312         i = 512;
313         j = 4096;
314         if (blocksize > 0) {
315                 i = j = blocksize;
316                 size = size / (blocksize / 512);
317         }
318         for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) {
319                 sbi->s_root_block = root_block;
320                 if (root_block < 0)
321                         sbi->s_root_block = (reserved + size - 1) / 2;
322                 pr_debug("AFFS: setting blocksize to %d\n", blocksize);
323                 affs_set_blocksize(sb, blocksize);
324                 sbi->s_partition_size = size;
325
326                 /* The root block location that was calculated above is not
327                  * correct if the partition size is an odd number of 512-
328                  * byte blocks, which will be rounded down to a number of
329                  * 1024-byte blocks, and if there were an even number of
330                  * reserved blocks. Ideally, all partition checkers should
331                  * report the real number of blocks of the real blocksize,
332                  * but since this just cannot be done, we have to try to
333                  * find the root block anyways. In the above case, it is one
334                  * block behind the calculated one. So we check this one, too.
335                  */
336                 for (num_bm = 0; num_bm < 2; num_bm++) {
337                         pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, "
338                                 "size=%d, reserved=%d\n",
339                                 sb->s_id,
340                                 sbi->s_root_block + num_bm,
341                                 blocksize, size, reserved);
342                         root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
343                         if (!root_bh)
344                                 continue;
345                         if (!affs_checksum_block(sb, root_bh) &&
346                             be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
347                             be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
348                                 sbi->s_hashsize    = blocksize / 4 - 56;
349                                 sbi->s_root_block += num_bm;
350                                 key                        = 1;
351                                 goto got_root;
352                         }
353                         affs_brelse(root_bh);
354                         root_bh = NULL;
355                 }
356         }
357         if (!silent)
358                 printk(KERN_ERR "AFFS: No valid root block on device %s\n",
359                         sb->s_id);
360         goto out_error;
361
362         /* N.B. after this point bh must be released */
363 got_root:
364         root_block = sbi->s_root_block;
365
366         /* Find out which kind of FS we have */
367         boot_bh = sb_bread(sb, 0);
368         if (!boot_bh) {
369                 printk(KERN_ERR "AFFS: Cannot read boot block\n");
370                 goto out_error;
371         }
372         chksum = be32_to_cpu(*(__be32 *)boot_bh->b_data);
373         brelse(boot_bh);
374
375         /* Dircache filesystems are compatible with non-dircache ones
376          * when reading. As long as they aren't supported, writing is
377          * not recommended.
378          */
379         if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
380              || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) {
381                 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n",
382                         sb->s_id);
383                 sb->s_flags |= MS_RDONLY;
384         }
385         switch (chksum) {
386                 case MUFS_FS:
387                 case MUFS_INTLFFS:
388                 case MUFS_DCFFS:
389                         sbi->s_flags |= SF_MUFS;
390                         /* fall thru */
391                 case FS_INTLFFS:
392                 case FS_DCFFS:
393                         sbi->s_flags |= SF_INTL;
394                         break;
395                 case MUFS_FFS:
396                         sbi->s_flags |= SF_MUFS;
397                         break;
398                 case FS_FFS:
399                         break;
400                 case MUFS_OFS:
401                         sbi->s_flags |= SF_MUFS;
402                         /* fall thru */
403                 case FS_OFS:
404                         sbi->s_flags |= SF_OFS;
405                         sb->s_flags |= MS_NOEXEC;
406                         break;
407                 case MUFS_DCOFS:
408                 case MUFS_INTLOFS:
409                         sbi->s_flags |= SF_MUFS;
410                 case FS_DCOFS:
411                 case FS_INTLOFS:
412                         sbi->s_flags |= SF_INTL | SF_OFS;
413                         sb->s_flags |= MS_NOEXEC;
414                         break;
415                 default:
416                         printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n",
417                                 sb->s_id, chksum);
418                         goto out_error;
419         }
420
421         if (mount_flags & SF_VERBOSE) {
422                 chksum = cpu_to_be32(chksum);
423                 printk(KERN_NOTICE "AFFS: Mounting volume \"%*s\": Type=%.3s\\%c, Blocksize=%d\n",
424                         AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0],
425                         AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
426                         (char *)&chksum,((char *)&chksum)[3] + '0',blocksize);
427         }
428
429         sb->s_flags |= MS_NODEV | MS_NOSUID;
430
431         sbi->s_data_blksize = sb->s_blocksize;
432         if (sbi->s_flags & SF_OFS)
433                 sbi->s_data_blksize -= 24;
434
435         /* Keep super block in cache */
436         sbi->s_root_bh = root_bh;
437         /* N.B. after this point s_root_bh must be released */
438
439         tmp_flags = sb->s_flags;
440         if (affs_init_bitmap(sb, &tmp_flags))
441                 goto out_error;
442         sb->s_flags = tmp_flags;
443
444         /* set up enough so that it can read an inode */
445
446         root_inode = iget(sb, root_block);
447         sb->s_root = d_alloc_root(root_inode);
448         if (!sb->s_root) {
449                 printk(KERN_ERR "AFFS: Get root inode failed\n");
450                 goto out_error;
451         }
452         sb->s_root->d_op = &affs_dentry_operations;
453
454         pr_debug("AFFS: s_flags=%lX\n",sb->s_flags);
455         return 0;
456
457         /*
458          * Begin the cascaded cleanup ...
459          */
460 out_error:
461         if (root_inode)
462                 iput(root_inode);
463         kfree(sbi->s_bitmap);
464         affs_brelse(root_bh);
465         kfree(sbi->s_prefix);
466         kfree(sbi);
467         sb->s_fs_info = NULL;
468         return -EINVAL;
469 }
470
471 static int
472 affs_remount(struct super_block *sb, int *flags, char *data)
473 {
474         struct affs_sb_info     *sbi = AFFS_SB(sb);
475         int                      blocksize;
476         uid_t                    uid;
477         gid_t                    gid;
478         int                      mode;
479         int                      reserved;
480         int                      root_block;
481         unsigned long            mount_flags;
482         int                      res = 0;
483
484         pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data);
485
486         *flags |= MS_NODIRATIME;
487
488         if (!parse_options(data,&uid,&gid,&mode,&reserved,&root_block,
489             &blocksize,&sbi->s_prefix,sbi->s_volume,&mount_flags))
490                 return -EINVAL;
491         sbi->s_flags = mount_flags;
492         sbi->s_mode  = mode;
493         sbi->s_uid   = uid;
494         sbi->s_gid   = gid;
495
496         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
497                 return 0;
498         if (*flags & MS_RDONLY) {
499                 sb->s_dirt = 1;
500                 while (sb->s_dirt)
501                         affs_write_super(sb);
502                 affs_free_bitmap(sb);
503         } else
504                 res = affs_init_bitmap(sb, flags);
505
506         return res;
507 }
508
509 static int
510 affs_statfs(struct super_block *sb, struct kstatfs *buf)
511 {
512         int              free;
513
514         pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size,
515              AFFS_SB(sb)->s_reserved);
516
517         free          = affs_count_free_blocks(sb);
518         buf->f_type    = AFFS_SUPER_MAGIC;
519         buf->f_bsize   = sb->s_blocksize;
520         buf->f_blocks  = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
521         buf->f_bfree   = free;
522         buf->f_bavail  = free;
523         return 0;
524 }
525
526 static struct super_block *affs_get_sb(struct file_system_type *fs_type,
527         int flags, const char *dev_name, void *data)
528 {
529         return get_sb_bdev(fs_type, flags, dev_name, data, affs_fill_super);
530 }
531
532 static struct file_system_type affs_fs_type = {
533         .owner          = THIS_MODULE,
534         .name           = "affs",
535         .get_sb         = affs_get_sb,
536         .kill_sb        = kill_block_super,
537         .fs_flags       = FS_REQUIRES_DEV,
538 };
539
540 static int __init init_affs_fs(void)
541 {
542         int err = init_inodecache();
543         if (err)
544                 goto out1;
545         err = register_filesystem(&affs_fs_type);
546         if (err)
547                 goto out;
548         return 0;
549 out:
550         destroy_inodecache();
551 out1:
552         return err;
553 }
554
555 static void __exit exit_affs_fs(void)
556 {
557         unregister_filesystem(&affs_fs_type);
558         destroy_inodecache();
559 }
560
561 MODULE_DESCRIPTION("Amiga filesystem support for Linux");
562 MODULE_LICENSE("GPL");
563
564 module_init(init_affs_fs)
565 module_exit(exit_affs_fs)