1
2
3
4
5
6
7
8
9#include <linux/module.h>
10#include <linux/mm.h>
11#include <linux/slab.h>
12#include <linux/init.h>
13#include <linux/fs.h>
14#include <linux/buffer_head.h>
15#include <linux/vfs.h>
16#include <linux/writeback.h>
17#include <linux/uio.h>
18#include <linux/uaccess.h>
19#include "bfs.h"
20
21MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>");
22MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
23MODULE_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
33struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
34{
35 struct bfs_inode *di;
36 struct inode *inode;
37 struct buffer_head *bh;
38 int block, off;
39
40 inode = iget_locked(sb, ino);
41 if (!inode)
42 return ERR_PTR(-ENOMEM);
43 if (!(inode->i_state & I_NEW))
44 return inode;
45
46 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
47 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
48 goto error;
49 }
50
51 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
52 bh = sb_bread(inode->i_sb, block);
53 if (!bh) {
54 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
55 ino);
56 goto error;
57 }
58
59 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
60 di = (struct bfs_inode *)bh->b_data + off;
61
62 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
63 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
64 inode->i_mode |= S_IFDIR;
65 inode->i_op = &bfs_dir_inops;
66 inode->i_fop = &bfs_dir_operations;
67 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
68 inode->i_mode |= S_IFREG;
69 inode->i_op = &bfs_file_inops;
70 inode->i_fop = &bfs_file_operations;
71 inode->i_mapping->a_ops = &bfs_aops;
72 }
73
74 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock);
75 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock);
76 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
77 i_uid_write(inode, le32_to_cpu(di->i_uid));
78 i_gid_write(inode, le32_to_cpu(di->i_gid));
79 set_nlink(inode, le32_to_cpu(di->i_nlink));
80 inode->i_size = BFS_FILESIZE(di);
81 inode->i_blocks = BFS_FILEBLOCKS(di);
82 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime);
83 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime);
84 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime);
85 inode->i_atime.tv_nsec = 0;
86 inode->i_mtime.tv_nsec = 0;
87 inode->i_ctime.tv_nsec = 0;
88
89 brelse(bh);
90 unlock_new_inode(inode);
91 return inode;
92
93error:
94 iget_failed(inode);
95 return ERR_PTR(-EIO);
96}
97
98static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p)
99{
100 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) {
101 printf("Bad inode number %s:%08x\n", sb->s_id, ino);
102 return ERR_PTR(-EIO);
103 }
104
105 ino -= BFS_ROOT_INO;
106
107 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
108 if (!*p) {
109 printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
110 return ERR_PTR(-EIO);
111 }
112
113 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK;
114}
115
116static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc)
117{
118 struct bfs_sb_info *info = BFS_SB(inode->i_sb);
119 unsigned int ino = (u16)inode->i_ino;
120 unsigned long i_sblock;
121 struct bfs_inode *di;
122 struct buffer_head *bh;
123 int err = 0;
124
125 dprintf("ino=%08x\n", ino);
126
127 di = find_inode(inode->i_sb, ino, &bh);
128 if (IS_ERR(di))
129 return PTR_ERR(di);
130
131 mutex_lock(&info->bfs_lock);
132
133 if (ino == BFS_ROOT_INO)
134 di->i_vtype = cpu_to_le32(BFS_VDIR);
135 else
136 di->i_vtype = cpu_to_le32(BFS_VREG);
137
138 di->i_ino = cpu_to_le16(ino);
139 di->i_mode = cpu_to_le32(inode->i_mode);
140 di->i_uid = cpu_to_le32(i_uid_read(inode));
141 di->i_gid = cpu_to_le32(i_gid_read(inode));
142 di->i_nlink = cpu_to_le32(inode->i_nlink);
143 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
144 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
145 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
146 i_sblock = BFS_I(inode)->i_sblock;
147 di->i_sblock = cpu_to_le32(i_sblock);
148 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
149 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
150
151 mark_buffer_dirty(bh);
152 if (wbc->sync_mode == WB_SYNC_ALL) {
153 sync_dirty_buffer(bh);
154 if (buffer_req(bh) && !buffer_uptodate(bh))
155 err = -EIO;
156 }
157 brelse(bh);
158 mutex_unlock(&info->bfs_lock);
159 return err;
160}
161
162static void bfs_evict_inode(struct inode *inode)
163{
164 unsigned long ino = inode->i_ino;
165 struct bfs_inode *di;
166 struct buffer_head *bh;
167 struct super_block *s = inode->i_sb;
168 struct bfs_sb_info *info = BFS_SB(s);
169 struct bfs_inode_info *bi = BFS_I(inode);
170
171 dprintf("ino=%08lx\n", ino);
172
173 truncate_inode_pages_final(&inode->i_data);
174 invalidate_inode_buffers(inode);
175 clear_inode(inode);
176
177 if (inode->i_nlink)
178 return;
179
180 di = find_inode(s, inode->i_ino, &bh);
181 if (IS_ERR(di))
182 return;
183
184 mutex_lock(&info->bfs_lock);
185
186 memset(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 bfs_dump_imap("evict_inode", s);
196 }
197
198
199
200
201
202
203 if (info->si_lf_eblk == bi->i_eblock)
204 info->si_lf_eblk = bi->i_sblock - 1;
205 mutex_unlock(&info->bfs_lock);
206}
207
208static void bfs_put_super(struct super_block *s)
209{
210 struct bfs_sb_info *info = BFS_SB(s);
211
212 if (!info)
213 return;
214
215 mutex_destroy(&info->bfs_lock);
216 kfree(info);
217 s->s_fs_info = NULL;
218}
219
220static 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
237static struct kmem_cache *bfs_inode_cachep;
238
239static struct inode *bfs_alloc_inode(struct super_block *sb)
240{
241 struct bfs_inode_info *bi;
242 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
243 if (!bi)
244 return NULL;
245 return &bi->vfs_inode;
246}
247
248static void bfs_i_callback(struct rcu_head *head)
249{
250 struct inode *inode = container_of(head, struct inode, i_rcu);
251 kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
252}
253
254static void bfs_destroy_inode(struct inode *inode)
255{
256 call_rcu(&inode->i_rcu, bfs_i_callback);
257}
258
259static void init_once(void *foo)
260{
261 struct bfs_inode_info *bi = foo;
262
263 inode_init_once(&bi->vfs_inode);
264}
265
266static int __init init_inodecache(void)
267{
268 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
269 sizeof(struct bfs_inode_info),
270 0, (SLAB_RECLAIM_ACCOUNT|
271 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
272 init_once);
273 if (bfs_inode_cachep == NULL)
274 return -ENOMEM;
275 return 0;
276}
277
278static void destroy_inodecache(void)
279{
280
281
282
283
284 rcu_barrier();
285 kmem_cache_destroy(bfs_inode_cachep);
286}
287
288static const struct super_operations bfs_sops = {
289 .alloc_inode = bfs_alloc_inode,
290 .destroy_inode = bfs_destroy_inode,
291 .write_inode = bfs_write_inode,
292 .evict_inode = bfs_evict_inode,
293 .put_super = bfs_put_super,
294 .statfs = bfs_statfs,
295};
296
297void bfs_dump_imap(const char *prefix, struct super_block *s)
298{
299#ifdef DEBUG
300 int i;
301 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
302
303 if (!tmpbuf)
304 return;
305 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
306 if (i > PAGE_SIZE - 100) break;
307 if (test_bit(i, BFS_SB(s)->si_imap))
308 strcat(tmpbuf, "1");
309 else
310 strcat(tmpbuf, "0");
311 }
312 printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
313 free_page((unsigned long)tmpbuf);
314#endif
315}
316
317static int bfs_fill_super(struct super_block *s, void *data, int silent)
318{
319 struct buffer_head *bh, *sbh;
320 struct bfs_super_block *bfs_sb;
321 struct inode *inode;
322 unsigned i;
323 struct bfs_sb_info *info;
324 int ret = -EINVAL;
325 unsigned long i_sblock, i_eblock, i_eoff, s_size;
326
327 info = kzalloc(sizeof(*info), GFP_KERNEL);
328 if (!info)
329 return -ENOMEM;
330 mutex_init(&info->bfs_lock);
331 s->s_fs_info = info;
332
333 sb_set_blocksize(s, BFS_BSIZE);
334
335 sbh = sb_bread(s, 0);
336 if (!sbh)
337 goto out;
338 bfs_sb = (struct bfs_super_block *)sbh->b_data;
339 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
340 if (!silent)
341 printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id, le32_to_cpu(bfs_sb->s_magic));
342 goto out1;
343 }
344 if (BFS_UNCLEAN(bfs_sb, s) && !silent)
345 printf("%s is unclean, continuing\n", s->s_id);
346
347 s->s_magic = BFS_MAGIC;
348
349 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) ||
350 le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) {
351 printf("Superblock is corrupted on %s\n", s->s_id);
352 goto out1;
353 }
354
355 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1;
356 if (info->si_lasti == BFS_MAX_LASTI)
357 printf("WARNING: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id);
358 else if (info->si_lasti > BFS_MAX_LASTI) {
359 printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id);
360 goto out1;
361 }
362 for (i = 0; i < BFS_ROOT_INO; i++)
363 set_bit(i, info->si_imap);
364
365 s->s_op = &bfs_sops;
366 inode = bfs_iget(s, BFS_ROOT_INO);
367 if (IS_ERR(inode)) {
368 ret = PTR_ERR(inode);
369 goto out1;
370 }
371 s->s_root = d_make_root(inode);
372 if (!s->s_root) {
373 ret = -ENOMEM;
374 goto out1;
375 }
376
377 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
378 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
379 info->si_freei = 0;
380 info->si_lf_eblk = 0;
381
382
383 bh = sb_bread(s, info->si_blocks - 1);
384 if (!bh) {
385 printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1);
386 ret = -EIO;
387 goto out2;
388 }
389 brelse(bh);
390
391 bh = NULL;
392 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
393 struct bfs_inode *di;
394 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
395 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
396 unsigned long eblock;
397
398 if (!off) {
399 brelse(bh);
400 bh = sb_bread(s, block);
401 }
402
403 if (!bh)
404 continue;
405
406 di = (struct bfs_inode *)bh->b_data + off;
407
408
409
410 i_eoff = le32_to_cpu(di->i_eoffset);
411 i_sblock = le32_to_cpu(di->i_sblock);
412 i_eblock = le32_to_cpu(di->i_eblock);
413 s_size = le32_to_cpu(bfs_sb->s_end);
414
415 if (i_sblock > info->si_blocks ||
416 i_eblock > info->si_blocks ||
417 i_sblock > i_eblock ||
418 (i_eoff != le32_to_cpu(-1) && i_eoff > s_size) ||
419 i_sblock * BFS_BSIZE > i_eoff) {
420
421 printf("Inode 0x%08x corrupted on %s\n", i, s->s_id);
422
423 brelse(bh);
424 ret = -EIO;
425 goto out2;
426 }
427
428 if (!di->i_ino) {
429 info->si_freei++;
430 continue;
431 }
432 set_bit(i, info->si_imap);
433 info->si_freeb -= BFS_FILEBLOCKS(di);
434
435 eblock = le32_to_cpu(di->i_eblock);
436 if (eblock > info->si_lf_eblk)
437 info->si_lf_eblk = eblock;
438 }
439 brelse(bh);
440 brelse(sbh);
441 bfs_dump_imap("fill_super", s);
442 return 0;
443
444out2:
445 dput(s->s_root);
446 s->s_root = NULL;
447out1:
448 brelse(sbh);
449out:
450 mutex_destroy(&info->bfs_lock);
451 kfree(info);
452 s->s_fs_info = NULL;
453 return ret;
454}
455
456static struct dentry *bfs_mount(struct file_system_type *fs_type,
457 int flags, const char *dev_name, void *data)
458{
459 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
460}
461
462static struct file_system_type bfs_fs_type = {
463 .owner = THIS_MODULE,
464 .name = "bfs",
465 .mount = bfs_mount,
466 .kill_sb = kill_block_super,
467 .fs_flags = FS_REQUIRES_DEV,
468};
469MODULE_ALIAS_FS("bfs");
470
471static int __init init_bfs_fs(void)
472{
473 int err = init_inodecache();
474 if (err)
475 goto out1;
476 err = register_filesystem(&bfs_fs_type);
477 if (err)
478 goto out;
479 return 0;
480out:
481 destroy_inodecache();
482out1:
483 return err;
484}
485
486static void __exit exit_bfs_fs(void)
487{
488 unregister_filesystem(&bfs_fs_type);
489 destroy_inodecache();
490}
491
492module_init(init_bfs_fs)
493module_exit(exit_bfs_fs)
494
