Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfashe...
[linux-2.6] / fs / bfs / inode.c
1 /*
2  *      fs/bfs/inode.c
3  *      BFS superblock and inode operations.
4  *      Copyright (C) 1999-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
5  *      From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
6  *
7  *      Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005.
8  */
9
10 #include <linux/module.h>
11 #include <linux/mm.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/fs.h>
15 #include <linux/smp_lock.h>
16 #include <linux/buffer_head.h>
17 #include <linux/vfs.h>
18 #include <asm/uaccess.h>
19 #include "bfs.h"
20
21 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
22 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
23 MODULE_LICENSE("GPL");
24
25 #undef DEBUG
26
27 #ifdef DEBUG
28 #define dprintf(x...)   printf(x)
29 #else
30 #define dprintf(x...)
31 #endif
32
33 void dump_imap(const char *prefix, struct super_block *s);
34
35 struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
36 {
37         struct bfs_inode *di;
38         struct inode *inode;
39         struct buffer_head *bh;
40         int block, off;
41
42         inode = iget_locked(sb, ino);
43         if (IS_ERR(inode))
44                 return ERR_PTR(-ENOMEM);
45         if (!(inode->i_state & I_NEW))
46                 return inode;
47
48         if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
49                 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
50                 goto error;
51         }
52
53         block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
54         bh = sb_bread(inode->i_sb, block);
55         if (!bh) {
56                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
57                                                                         ino);
58                 goto error;
59         }
60
61         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
62         di = (struct bfs_inode *)bh->b_data + off;
63
64         inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
65         if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
66                 inode->i_mode |= S_IFDIR;
67                 inode->i_op = &bfs_dir_inops;
68                 inode->i_fop = &bfs_dir_operations;
69         } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
70                 inode->i_mode |= S_IFREG;
71                 inode->i_op = &bfs_file_inops;
72                 inode->i_fop = &bfs_file_operations;
73                 inode->i_mapping->a_ops = &bfs_aops;
74         }
75
76         BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
77         BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
78         BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
79         inode->i_uid =  le32_to_cpu(di->i_uid);
80         inode->i_gid =  le32_to_cpu(di->i_gid);
81         inode->i_nlink =  le32_to_cpu(di->i_nlink);
82         inode->i_size = BFS_FILESIZE(di);
83         inode->i_blocks = BFS_FILEBLOCKS(di);
84         inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
85         inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
86         inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
87         inode->i_atime.tv_nsec = 0;
88         inode->i_mtime.tv_nsec = 0;
89         inode->i_ctime.tv_nsec = 0;
90
91         brelse(bh);
92         unlock_new_inode(inode);
93         return inode;
94
95 error:
96         iget_failed(inode);
97         return ERR_PTR(-EIO);
98 }
99
100 static int bfs_write_inode(struct inode *inode, int unused)
101 {
102         unsigned int ino = (u16)inode->i_ino;
103         unsigned long i_sblock;
104         struct bfs_inode *di;
105         struct buffer_head *bh;
106         int block, off;
107
108         dprintf("ino=%08x\n", ino);
109
110         if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
111                 printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
112                 return -EIO;
113         }
114
115         lock_kernel();
116         block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
117         bh = sb_bread(inode->i_sb, block);
118         if (!bh) {
119                 printf("Unable to read inode %s:%08x\n",
120                                 inode->i_sb->s_id, ino);
121                 unlock_kernel();
122                 return -EIO;
123         }
124
125         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
126         di = (struct bfs_inode *)bh->b_data + off;
127
128         if (ino == BFS_ROOT_INO)
129                 di->i_vtype = cpu_to_le32(BFS_VDIR);
130         else
131                 di->i_vtype = cpu_to_le32(BFS_VREG);
132
133         di->i_ino = cpu_to_le16(ino);
134         di->i_mode = cpu_to_le32(inode->i_mode);
135         di->i_uid = cpu_to_le32(inode->i_uid);
136         di->i_gid = cpu_to_le32(inode->i_gid);
137         di->i_nlink = cpu_to_le32(inode->i_nlink);
138         di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
139         di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
140         di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
141         i_sblock = BFS_I(inode)->i_sblock;
142         di->i_sblock = cpu_to_le32(i_sblock);
143         di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
144         di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
145
146         mark_buffer_dirty(bh);
147         brelse(bh);
148         unlock_kernel();
149         return 0;
150 }
151
152 static void bfs_delete_inode(struct inode *inode)
153 {
154         unsigned long ino = inode->i_ino;
155         struct bfs_inode *di;
156         struct buffer_head *bh;
157         int block, off;
158         struct super_block *s = inode->i_sb;
159         struct bfs_sb_info *info = BFS_SB(s);
160         struct bfs_inode_info *bi = BFS_I(inode);
161
162         dprintf("ino=%08lx\n", ino);
163
164         truncate_inode_pages(&inode->i_data, 0);
165
166         if ((ino < BFS_ROOT_INO) || (ino > info->si_lasti)) {
167                 printf("invalid ino=%08lx\n", ino);
168                 return;
169         }
170         
171         inode->i_size = 0;
172         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
173         lock_kernel();
174         mark_inode_dirty(inode);
175
176         block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
177         bh = sb_bread(s, block);
178         if (!bh) {
179                 printf("Unable to read inode %s:%08lx\n",
180                                         inode->i_sb->s_id, ino);
181                 unlock_kernel();
182                 return;
183         }
184         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
185         di = (struct bfs_inode *)bh->b_data + off;
186         memset((void *)di, 0, sizeof(struct bfs_inode));
187         mark_buffer_dirty(bh);
188         brelse(bh);
189
190         if (bi->i_dsk_ino) {
191                 if (bi->i_sblock)
192                         info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
193                 info->si_freei++;
194                 clear_bit(ino, info->si_imap);
195                 dump_imap("delete_inode", s);
196         }
197
198         /*
199          * If this was the last file, make the previous block
200          * "last block of the last file" even if there is no
201          * real file there, saves us 1 gap.
202          */
203         if (info->si_lf_eblk == bi->i_eblock) {
204                 info->si_lf_eblk = bi->i_sblock - 1;
205                 mark_buffer_dirty(info->si_sbh);
206         }
207         unlock_kernel();
208         clear_inode(inode);
209 }
210
211 static void bfs_put_super(struct super_block *s)
212 {
213         struct bfs_sb_info *info = BFS_SB(s);
214         brelse(info->si_sbh);
215         kfree(info->si_imap);
216         kfree(info);
217         s->s_fs_info = NULL;
218 }
219
220 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
221 {
222         struct super_block *s = dentry->d_sb;
223         struct bfs_sb_info *info = BFS_SB(s);
224         u64 id = huge_encode_dev(s->s_bdev->bd_dev);
225         buf->f_type = BFS_MAGIC;
226         buf->f_bsize = s->s_blocksize;
227         buf->f_blocks = info->si_blocks;
228         buf->f_bfree = buf->f_bavail = info->si_freeb;
229         buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
230         buf->f_ffree = info->si_freei;
231         buf->f_fsid.val[0] = (u32)id;
232         buf->f_fsid.val[1] = (u32)(id >> 32);
233         buf->f_namelen = BFS_NAMELEN;
234         return 0;
235 }
236
237 static void bfs_write_super(struct super_block *s)
238 {
239         lock_kernel();
240         if (!(s->s_flags & MS_RDONLY))
241                 mark_buffer_dirty(BFS_SB(s)->si_sbh);
242         s->s_dirt = 0;
243         unlock_kernel();
244 }
245
246 static struct kmem_cache *bfs_inode_cachep;
247
248 static struct inode *bfs_alloc_inode(struct super_block *sb)
249 {
250         struct bfs_inode_info *bi;
251         bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
252         if (!bi)
253                 return NULL;
254         return &bi->vfs_inode;
255 }
256
257 static void bfs_destroy_inode(struct inode *inode)
258 {
259         kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
260 }
261
262 static void init_once(struct kmem_cache *cachep, void *foo)
263 {
264         struct bfs_inode_info *bi = foo;
265
266         inode_init_once(&bi->vfs_inode);
267 }
268
269 static int init_inodecache(void)
270 {
271         bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
272                                              sizeof(struct bfs_inode_info),
273                                              0, (SLAB_RECLAIM_ACCOUNT|
274                                                 SLAB_MEM_SPREAD),
275                                              init_once);
276         if (bfs_inode_cachep == NULL)
277                 return -ENOMEM;
278         return 0;
279 }
280
281 static void destroy_inodecache(void)
282 {
283         kmem_cache_destroy(bfs_inode_cachep);
284 }
285
286 static const struct super_operations bfs_sops = {
287         .alloc_inode    = bfs_alloc_inode,
288         .destroy_inode  = bfs_destroy_inode,
289         .write_inode    = bfs_write_inode,
290         .delete_inode   = bfs_delete_inode,
291         .put_super      = bfs_put_super,
292         .write_super    = bfs_write_super,
293         .statfs         = bfs_statfs,
294 };
295
296 void dump_imap(const char *prefix, struct super_block *s)
297 {
298 #ifdef DEBUG
299         int i;
300         char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
301
302         if (!tmpbuf)
303                 return;
304         for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
305                 if (i > PAGE_SIZE - 100) break;
306                 if (test_bit(i, BFS_SB(s)->si_imap))
307                         strcat(tmpbuf, "1");
308                 else
309                         strcat(tmpbuf, "0");
310         }
311         printf("BFS-fs: %s: lasti=%08lx <%s>\n",
312                                 prefix, BFS_SB(s)->si_lasti, tmpbuf);
313         free_page((unsigned long)tmpbuf);
314 #endif
315 }
316
317 static int bfs_fill_super(struct super_block *s, void *data, int silent)
318 {
319         struct buffer_head *bh;
320         struct bfs_super_block *bfs_sb;
321         struct inode *inode;
322         unsigned i, imap_len;
323         struct bfs_sb_info *info;
324         long ret = -EINVAL;
325
326         info = kzalloc(sizeof(*info), GFP_KERNEL);
327         if (!info)
328                 return -ENOMEM;
329         s->s_fs_info = info;
330
331         sb_set_blocksize(s, BFS_BSIZE);
332
333         bh = sb_bread(s, 0);
334         if(!bh)
335                 goto out;
336         bfs_sb = (struct bfs_super_block *)bh->b_data;
337         if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
338                 if (!silent)
339                         printf("No BFS filesystem on %s (magic=%08x)\n", 
340                                 s->s_id,  le32_to_cpu(bfs_sb->s_magic));
341                 goto out;
342         }
343         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
344                 printf("%s is unclean, continuing\n", s->s_id);
345
346         s->s_magic = BFS_MAGIC;
347         info->si_sbh = bh;
348         info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
349                                         sizeof(struct bfs_inode)
350                                         + BFS_ROOT_INO - 1;
351         imap_len = (info->si_lasti / 8) + 1;
352         info->si_imap = kzalloc(imap_len, GFP_KERNEL);
353         if (!info->si_imap)
354                 goto out;
355         for (i = 0; i < BFS_ROOT_INO; i++)
356                 set_bit(i, info->si_imap);
357
358         s->s_op = &bfs_sops;
359         inode = bfs_iget(s, BFS_ROOT_INO);
360         if (IS_ERR(inode)) {
361                 ret = PTR_ERR(inode);
362                 kfree(info->si_imap);
363                 goto out;
364         }
365         s->s_root = d_alloc_root(inode);
366         if (!s->s_root) {
367                 iput(inode);
368                 ret = -ENOMEM;
369                 kfree(info->si_imap);
370                 goto out;
371         }
372
373         info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
374         info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
375                         - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
376         info->si_freei = 0;
377         info->si_lf_eblk = 0;
378         bh = NULL;
379         for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
380                 struct bfs_inode *di;
381                 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
382                 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
383                 unsigned long sblock, eblock;
384
385                 if (!off) {
386                         brelse(bh);
387                         bh = sb_bread(s, block);
388                 }
389
390                 if (!bh)
391                         continue;
392
393                 di = (struct bfs_inode *)bh->b_data + off;
394
395                 if (!di->i_ino) {
396                         info->si_freei++;
397                         continue;
398                 }
399                 set_bit(i, info->si_imap);
400                 info->si_freeb -= BFS_FILEBLOCKS(di);
401
402                 sblock =  le32_to_cpu(di->i_sblock);
403                 eblock =  le32_to_cpu(di->i_eblock);
404                 if (eblock > info->si_lf_eblk)
405                         info->si_lf_eblk = eblock;
406         }
407         brelse(bh);
408         if (!(s->s_flags & MS_RDONLY)) {
409                 mark_buffer_dirty(info->si_sbh);
410                 s->s_dirt = 1;
411         } 
412         dump_imap("read_super", s);
413         return 0;
414
415 out:
416         brelse(bh);
417         kfree(info);
418         s->s_fs_info = NULL;
419         return ret;
420 }
421
422 static int bfs_get_sb(struct file_system_type *fs_type,
423         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
424 {
425         return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
426 }
427
428 static struct file_system_type bfs_fs_type = {
429         .owner          = THIS_MODULE,
430         .name           = "bfs",
431         .get_sb         = bfs_get_sb,
432         .kill_sb        = kill_block_super,
433         .fs_flags       = FS_REQUIRES_DEV,
434 };
435
436 static int __init init_bfs_fs(void)
437 {
438         int err = init_inodecache();
439         if (err)
440                 goto out1;
441         err = register_filesystem(&bfs_fs_type);
442         if (err)
443                 goto out;
444         return 0;
445 out:
446         destroy_inodecache();
447 out1:
448         return err;
449 }
450
451 static void __exit exit_bfs_fs(void)
452 {
453         unregister_filesystem(&bfs_fs_type);
454         destroy_inodecache();
455 }
456
457 module_init(init_bfs_fs)
458 module_exit(exit_bfs_fs)