584a0838ac610ec4787439629550d21b54e5d91c
[linux-3.10.git] / fs / bfs / inode.c
1 /*
2  *      fs/bfs/inode.c
3  *      BFS superblock and inode operations.
4  *      Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
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 A. Aivazian <tigran@veritas.com>");
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 static void bfs_read_inode(struct inode * inode)
36 {
37         unsigned long ino = inode->i_ino;
38         struct bfs_inode * di;
39         struct buffer_head * bh;
40         int block, off;
41
42         if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
43                 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
44                 make_bad_inode(inode);
45                 return;
46         }
47
48         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
49         bh = sb_bread(inode->i_sb, block);
50         if (!bh) {
51                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
52                 make_bad_inode(inode);
53                 return;
54         }
55
56         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
57         di = (struct bfs_inode *)bh->b_data + off;
58
59         inode->i_mode = 0x0000FFFF &  le32_to_cpu(di->i_mode);
60         if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
61                 inode->i_mode |= S_IFDIR;
62                 inode->i_op = &bfs_dir_inops;
63                 inode->i_fop = &bfs_dir_operations;
64         } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
65                 inode->i_mode |= S_IFREG;
66                 inode->i_op = &bfs_file_inops;
67                 inode->i_fop = &bfs_file_operations;
68                 inode->i_mapping->a_ops = &bfs_aops;
69         }
70
71         BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
72         BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
73         inode->i_uid =  le32_to_cpu(di->i_uid);
74         inode->i_gid =  le32_to_cpu(di->i_gid);
75         inode->i_nlink =  le32_to_cpu(di->i_nlink);
76         inode->i_size = BFS_FILESIZE(di);
77         inode->i_blocks = BFS_FILEBLOCKS(di);
78         if (inode->i_size || inode->i_blocks) dprintf("Registered inode with %lld size, %ld blocks\n", inode->i_size, inode->i_blocks);
79         inode->i_blksize = PAGE_SIZE;
80         inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
81         inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
82         inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
83         inode->i_atime.tv_nsec = 0;
84         inode->i_mtime.tv_nsec = 0;
85         inode->i_ctime.tv_nsec = 0;
86         BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); /* can be 0 so we store a copy */
87
88         brelse(bh);
89 }
90
91 static int bfs_write_inode(struct inode * inode, int unused)
92 {
93         unsigned int ino = (u16)inode->i_ino;
94         unsigned long i_sblock;
95         struct bfs_inode * di;
96         struct buffer_head * bh;
97         int block, off;
98
99         dprintf("ino=%08x\n", ino);
100
101         if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
102                 printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
103                 return -EIO;
104         }
105
106         lock_kernel();
107         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
108         bh = sb_bread(inode->i_sb, block);
109         if (!bh) {
110                 printf("Unable to read inode %s:%08x\n", inode->i_sb->s_id, ino);
111                 unlock_kernel();
112                 return -EIO;
113         }
114
115         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
116         di = (struct bfs_inode *)bh->b_data + off;
117
118         if (ino == BFS_ROOT_INO)
119                 di->i_vtype = cpu_to_le32(BFS_VDIR);
120         else
121                 di->i_vtype = cpu_to_le32(BFS_VREG);
122
123         di->i_ino = cpu_to_le16(ino);
124         di->i_mode = cpu_to_le32(inode->i_mode);
125         di->i_uid = cpu_to_le32(inode->i_uid);
126         di->i_gid = cpu_to_le32(inode->i_gid);
127         di->i_nlink = cpu_to_le32(inode->i_nlink);
128         di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
129         di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
130         di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
131         i_sblock = BFS_I(inode)->i_sblock;
132         di->i_sblock = cpu_to_le32(i_sblock);
133         di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
134         di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
135
136         mark_buffer_dirty(bh);
137         dprintf("Written ino=%d into %d:%d\n",le16_to_cpu(di->i_ino),block,off);
138         brelse(bh);
139         unlock_kernel();
140         return 0;
141 }
142
143 static void bfs_delete_inode(struct inode * inode)
144 {
145         unsigned long ino = inode->i_ino;
146         struct bfs_inode * di;
147         struct buffer_head * bh;
148         int block, off;
149         struct super_block * s = inode->i_sb;
150         struct bfs_sb_info * info = BFS_SB(s);
151         struct bfs_inode_info * bi = BFS_I(inode);
152
153         dprintf("ino=%08lx\n", ino);
154
155         truncate_inode_pages(&inode->i_data, 0);
156
157         if (ino < BFS_ROOT_INO || ino > info->si_lasti) {
158                 printf("invalid ino=%08lx\n", ino);
159                 return;
160         }
161         
162         inode->i_size = 0;
163         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
164         lock_kernel();
165         mark_inode_dirty(inode);
166         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
167         bh = sb_bread(s, block);
168         if (!bh) {
169                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
170                 unlock_kernel();
171                 return;
172         }
173         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
174         di = (struct bfs_inode *) bh->b_data + off;
175         if (bi->i_dsk_ino) {
176                 info->si_freeb += 1 + bi->i_eblock - bi->i_sblock;
177                 info->si_freei++;
178                 clear_bit(ino, info->si_imap);
179                 dump_imap("delete_inode", s);
180         }
181         di->i_ino = 0;
182         di->i_sblock = 0;
183         mark_buffer_dirty(bh);
184         brelse(bh);
185
186         /* if this was the last file, make the previous 
187            block "last files last block" even if there is no real file there,
188            saves us 1 gap */
189         if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
190                 info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
191                 mark_buffer_dirty(info->si_sbh);
192         }
193         unlock_kernel();
194         clear_inode(inode);
195 }
196
197 static void bfs_put_super(struct super_block *s)
198 {
199         struct bfs_sb_info *info = BFS_SB(s);
200         brelse(info->si_sbh);
201         kfree(info->si_imap);
202         kfree(info);
203         s->s_fs_info = NULL;
204 }
205
206 static int bfs_statfs(struct super_block *s, struct kstatfs *buf)
207 {
208         struct bfs_sb_info *info = BFS_SB(s);
209         u64 id = huge_encode_dev(s->s_bdev->bd_dev);
210         buf->f_type = BFS_MAGIC;
211         buf->f_bsize = s->s_blocksize;
212         buf->f_blocks = info->si_blocks;
213         buf->f_bfree = buf->f_bavail = info->si_freeb;
214         buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
215         buf->f_ffree = info->si_freei;
216         buf->f_fsid.val[0] = (u32)id;
217         buf->f_fsid.val[1] = (u32)(id >> 32);
218         buf->f_namelen = BFS_NAMELEN;
219         return 0;
220 }
221
222 static void bfs_write_super(struct super_block *s)
223 {
224         lock_kernel();
225         if (!(s->s_flags & MS_RDONLY))
226                 mark_buffer_dirty(BFS_SB(s)->si_sbh);
227         s->s_dirt = 0;
228         unlock_kernel();
229 }
230
231 static kmem_cache_t * bfs_inode_cachep;
232
233 static struct inode *bfs_alloc_inode(struct super_block *sb)
234 {
235         struct bfs_inode_info *bi;
236         bi = kmem_cache_alloc(bfs_inode_cachep, SLAB_KERNEL);
237         if (!bi)
238                 return NULL;
239         return &bi->vfs_inode;
240 }
241
242 static void bfs_destroy_inode(struct inode *inode)
243 {
244         kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
245 }
246
247 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
248 {
249         struct bfs_inode_info *bi = foo;
250
251         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
252             SLAB_CTOR_CONSTRUCTOR)
253                 inode_init_once(&bi->vfs_inode);
254 }
255  
256 static int init_inodecache(void)
257 {
258         bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
259                                              sizeof(struct bfs_inode_info),
260                                              0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
261                                              init_once, NULL);
262         if (bfs_inode_cachep == NULL)
263                 return -ENOMEM;
264         return 0;
265 }
266
267 static void destroy_inodecache(void)
268 {
269         if (kmem_cache_destroy(bfs_inode_cachep))
270                 printk(KERN_INFO "bfs_inode_cache: not all structures were freed\n");
271 }
272
273 static struct super_operations bfs_sops = {
274         .alloc_inode    = bfs_alloc_inode,
275         .destroy_inode  = bfs_destroy_inode,
276         .read_inode     = bfs_read_inode,
277         .write_inode    = bfs_write_inode,
278         .delete_inode   = bfs_delete_inode,
279         .put_super      = bfs_put_super,
280         .write_super    = bfs_write_super,
281         .statfs         = bfs_statfs,
282 };
283
284 void dump_imap(const char *prefix, struct super_block * s)
285 {
286 #ifdef DEBUG
287         int i;
288         char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
289
290         if (!tmpbuf)
291                 return;
292         for (i=BFS_SB(s)->si_lasti; i>=0; i--) {
293                 if (i > PAGE_SIZE-100) break;
294                 if (test_bit(i, BFS_SB(s)->si_imap))
295                         strcat(tmpbuf, "1");
296                 else
297                         strcat(tmpbuf, "0");
298         }
299         printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
300         free_page((unsigned long)tmpbuf);
301 #endif
302 }
303
304 static int bfs_fill_super(struct super_block *s, void *data, int silent)
305 {
306         struct buffer_head * bh;
307         struct bfs_super_block * bfs_sb;
308         struct inode * inode;
309         unsigned i, imap_len;
310         struct bfs_sb_info * info;
311
312         info = kmalloc(sizeof(*info), GFP_KERNEL);
313         if (!info)
314                 return -ENOMEM;
315         s->s_fs_info = info;
316         memset(info, 0, sizeof(*info));
317
318         sb_set_blocksize(s, BFS_BSIZE);
319
320         bh = sb_bread(s, 0);
321         if(!bh)
322                 goto out;
323         bfs_sb = (struct bfs_super_block *)bh->b_data;
324         if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
325                 if (!silent)
326                         printf("No BFS filesystem on %s (magic=%08x)\n", 
327                                 s->s_id,  le32_to_cpu(bfs_sb->s_magic));
328                 goto out;
329         }
330         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
331                 printf("%s is unclean, continuing\n", s->s_id);
332
333         s->s_magic = BFS_MAGIC;
334         info->si_sbh = bh;
335         info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE)/sizeof(struct bfs_inode)
336                         + BFS_ROOT_INO - 1;
337
338         imap_len = info->si_lasti/8 + 1;
339         info->si_imap = kmalloc(imap_len, GFP_KERNEL);
340         if (!info->si_imap)
341                 goto out;
342         memset(info->si_imap, 0, imap_len);
343         for (i=0; i<BFS_ROOT_INO; i++) 
344                 set_bit(i, info->si_imap);
345
346         s->s_op = &bfs_sops;
347         inode = iget(s, BFS_ROOT_INO);
348         if (!inode) {
349                 kfree(info->si_imap);
350                 goto out;
351         }
352         s->s_root = d_alloc_root(inode);
353         if (!s->s_root) {
354                 iput(inode);
355                 kfree(info->si_imap);
356                 goto out;
357         }
358
359         info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
360         info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 -  le32_to_cpu(bfs_sb->s_start))>>BFS_BSIZE_BITS;
361         info->si_freei = 0;
362         info->si_lf_eblk = 0;
363         info->si_lf_sblk = 0;
364         info->si_lf_ioff = 0;
365         bh = NULL;
366         for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
367                 struct bfs_inode *di;
368                 int block = (i - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
369                 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
370                 unsigned long sblock, eblock;
371
372                 if (!off) {
373                         brelse(bh);
374                         bh = sb_bread(s, block);
375                 }
376
377                 if (!bh)
378                         continue;
379
380                 di = (struct bfs_inode *)bh->b_data + off;
381
382                 if (!di->i_ino) {
383                         info->si_freei++;
384                         continue;
385                 }
386                 set_bit(i, info->si_imap);
387                 info->si_freeb -= BFS_FILEBLOCKS(di);
388
389                 sblock =  le32_to_cpu(di->i_sblock);
390                 eblock =  le32_to_cpu(di->i_eblock);
391                 if (eblock > info->si_lf_eblk) {
392                         info->si_lf_eblk = eblock;
393                         info->si_lf_sblk = sblock;
394                         info->si_lf_ioff = BFS_INO2OFF(i);
395                 }
396         }
397         brelse(bh);
398         if (!(s->s_flags & MS_RDONLY)) {
399                 mark_buffer_dirty(info->si_sbh);
400                 s->s_dirt = 1;
401         } 
402         dump_imap("read_super", s);
403         return 0;
404
405 out:
406         brelse(bh);
407         kfree(info);
408         s->s_fs_info = NULL;
409         return -EINVAL;
410 }
411
412 static struct super_block *bfs_get_sb(struct file_system_type *fs_type,
413         int flags, const char *dev_name, void *data)
414 {
415         return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
416 }
417
418 static struct file_system_type bfs_fs_type = {
419         .owner          = THIS_MODULE,
420         .name           = "bfs",
421         .get_sb         = bfs_get_sb,
422         .kill_sb        = kill_block_super,
423         .fs_flags       = FS_REQUIRES_DEV,
424 };
425
426 static int __init init_bfs_fs(void)
427 {
428         int err = init_inodecache();
429         if (err)
430                 goto out1;
431         err = register_filesystem(&bfs_fs_type);
432         if (err)
433                 goto out;
434         return 0;
435 out:
436         destroy_inodecache();
437 out1:
438         return err;
439 }
440
441 static void __exit exit_bfs_fs(void)
442 {
443         unregister_filesystem(&bfs_fs_type);
444         destroy_inodecache();
445 }
446
447 module_init(init_bfs_fs)
448 module_exit(exit_bfs_fs)