2e45123c8f7afd3f65858c9530d2128782257693
[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_atime.tv_sec =  le32_to_cpu(di->i_atime);
80         inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
81         inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
82         inode->i_atime.tv_nsec = 0;
83         inode->i_mtime.tv_nsec = 0;
84         inode->i_ctime.tv_nsec = 0;
85         BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); /* can be 0 so we store a copy */
86
87         brelse(bh);
88 }
89
90 static int bfs_write_inode(struct inode * inode, int unused)
91 {
92         unsigned int ino = (u16)inode->i_ino;
93         unsigned long i_sblock;
94         struct bfs_inode * di;
95         struct buffer_head * bh;
96         int block, off;
97
98         dprintf("ino=%08x\n", ino);
99
100         if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
101                 printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
102                 return -EIO;
103         }
104
105         lock_kernel();
106         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
107         bh = sb_bread(inode->i_sb, block);
108         if (!bh) {
109                 printf("Unable to read inode %s:%08x\n", inode->i_sb->s_id, ino);
110                 unlock_kernel();
111                 return -EIO;
112         }
113
114         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
115         di = (struct bfs_inode *)bh->b_data + off;
116
117         if (ino == BFS_ROOT_INO)
118                 di->i_vtype = cpu_to_le32(BFS_VDIR);
119         else
120                 di->i_vtype = cpu_to_le32(BFS_VREG);
121
122         di->i_ino = cpu_to_le16(ino);
123         di->i_mode = cpu_to_le32(inode->i_mode);
124         di->i_uid = cpu_to_le32(inode->i_uid);
125         di->i_gid = cpu_to_le32(inode->i_gid);
126         di->i_nlink = cpu_to_le32(inode->i_nlink);
127         di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
128         di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
129         di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
130         i_sblock = BFS_I(inode)->i_sblock;
131         di->i_sblock = cpu_to_le32(i_sblock);
132         di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
133         di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
134
135         mark_buffer_dirty(bh);
136         dprintf("Written ino=%d into %d:%d\n",le16_to_cpu(di->i_ino),block,off);
137         brelse(bh);
138         unlock_kernel();
139         return 0;
140 }
141
142 static void bfs_delete_inode(struct inode * inode)
143 {
144         unsigned long ino = inode->i_ino;
145         struct bfs_inode * di;
146         struct buffer_head * bh;
147         int block, off;
148         struct super_block * s = inode->i_sb;
149         struct bfs_sb_info * info = BFS_SB(s);
150         struct bfs_inode_info * bi = BFS_I(inode);
151
152         dprintf("ino=%08lx\n", ino);
153
154         truncate_inode_pages(&inode->i_data, 0);
155
156         if (ino < BFS_ROOT_INO || ino > info->si_lasti) {
157                 printf("invalid ino=%08lx\n", ino);
158                 return;
159         }
160         
161         inode->i_size = 0;
162         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
163         lock_kernel();
164         mark_inode_dirty(inode);
165         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
166         bh = sb_bread(s, block);
167         if (!bh) {
168                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
169                 unlock_kernel();
170                 return;
171         }
172         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
173         di = (struct bfs_inode *) bh->b_data + off;
174         if (bi->i_dsk_ino) {
175                 info->si_freeb += 1 + bi->i_eblock - bi->i_sblock;
176                 info->si_freei++;
177                 clear_bit(ino, info->si_imap);
178                 dump_imap("delete_inode", s);
179         }
180         di->i_ino = 0;
181         di->i_sblock = 0;
182         mark_buffer_dirty(bh);
183         brelse(bh);
184
185         /* if this was the last file, make the previous 
186            block "last files last block" even if there is no real file there,
187            saves us 1 gap */
188         if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
189                 info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
190                 mark_buffer_dirty(info->si_sbh);
191         }
192         unlock_kernel();
193         clear_inode(inode);
194 }
195
196 static void bfs_put_super(struct super_block *s)
197 {
198         struct bfs_sb_info *info = BFS_SB(s);
199         brelse(info->si_sbh);
200         kfree(info->si_imap);
201         kfree(info);
202         s->s_fs_info = NULL;
203 }
204
205 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
206 {
207         struct super_block *s = dentry->d_sb;
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, GFP_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|
261                                                 SLAB_MEM_SPREAD),
262                                              init_once, NULL);
263         if (bfs_inode_cachep == NULL)
264                 return -ENOMEM;
265         return 0;
266 }
267
268 static void destroy_inodecache(void)
269 {
270         kmem_cache_destroy(bfs_inode_cachep);
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 = kzalloc(sizeof(*info), GFP_KERNEL);
313         if (!info)
314                 return -ENOMEM;
315         s->s_fs_info = info;
316
317         sb_set_blocksize(s, BFS_BSIZE);
318
319         bh = sb_bread(s, 0);
320         if(!bh)
321                 goto out;
322         bfs_sb = (struct bfs_super_block *)bh->b_data;
323         if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
324                 if (!silent)
325                         printf("No BFS filesystem on %s (magic=%08x)\n", 
326                                 s->s_id,  le32_to_cpu(bfs_sb->s_magic));
327                 goto out;
328         }
329         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
330                 printf("%s is unclean, continuing\n", s->s_id);
331
332         s->s_magic = BFS_MAGIC;
333         info->si_sbh = bh;
334         info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE)/sizeof(struct bfs_inode)
335                         + BFS_ROOT_INO - 1;
336
337         imap_len = info->si_lasti/8 + 1;
338         info->si_imap = kzalloc(imap_len, GFP_KERNEL);
339         if (!info->si_imap)
340                 goto out;
341         for (i=0; i<BFS_ROOT_INO; i++) 
342                 set_bit(i, info->si_imap);
343
344         s->s_op = &bfs_sops;
345         inode = iget(s, BFS_ROOT_INO);
346         if (!inode) {
347                 kfree(info->si_imap);
348                 goto out;
349         }
350         s->s_root = d_alloc_root(inode);
351         if (!s->s_root) {
352                 iput(inode);
353                 kfree(info->si_imap);
354                 goto out;
355         }
356
357         info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
358         info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 -  le32_to_cpu(bfs_sb->s_start))>>BFS_BSIZE_BITS;
359         info->si_freei = 0;
360         info->si_lf_eblk = 0;
361         info->si_lf_sblk = 0;
362         info->si_lf_ioff = 0;
363         bh = NULL;
364         for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
365                 struct bfs_inode *di;
366                 int block = (i - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
367                 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
368                 unsigned long sblock, eblock;
369
370                 if (!off) {
371                         brelse(bh);
372                         bh = sb_bread(s, block);
373                 }
374
375                 if (!bh)
376                         continue;
377
378                 di = (struct bfs_inode *)bh->b_data + off;
379
380                 if (!di->i_ino) {
381                         info->si_freei++;
382                         continue;
383                 }
384                 set_bit(i, info->si_imap);
385                 info->si_freeb -= BFS_FILEBLOCKS(di);
386
387                 sblock =  le32_to_cpu(di->i_sblock);
388                 eblock =  le32_to_cpu(di->i_eblock);
389                 if (eblock > info->si_lf_eblk) {
390                         info->si_lf_eblk = eblock;
391                         info->si_lf_sblk = sblock;
392                         info->si_lf_ioff = BFS_INO2OFF(i);
393                 }
394         }
395         brelse(bh);
396         if (!(s->s_flags & MS_RDONLY)) {
397                 mark_buffer_dirty(info->si_sbh);
398                 s->s_dirt = 1;
399         } 
400         dump_imap("read_super", s);
401         return 0;
402
403 out:
404         brelse(bh);
405         kfree(info);
406         s->s_fs_info = NULL;
407         return -EINVAL;
408 }
409
410 static int bfs_get_sb(struct file_system_type *fs_type,
411         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
412 {
413         return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
414 }
415
416 static struct file_system_type bfs_fs_type = {
417         .owner          = THIS_MODULE,
418         .name           = "bfs",
419         .get_sb         = bfs_get_sb,
420         .kill_sb        = kill_block_super,
421         .fs_flags       = FS_REQUIRES_DEV,
422 };
423
424 static int __init init_bfs_fs(void)
425 {
426         int err = init_inodecache();
427         if (err)
428                 goto out1;
429         err = register_filesystem(&bfs_fs_type);
430         if (err)
431                 goto out;
432         return 0;
433 out:
434         destroy_inodecache();
435 out1:
436         return err;
437 }
438
439 static void __exit exit_bfs_fs(void)
440 {
441         unregister_filesystem(&bfs_fs_type);
442         destroy_inodecache();
443 }
444
445 module_init(init_bfs_fs)
446 module_exit(exit_bfs_fs)