1
2
3
4
5
6
7
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/buffer_head.h>
16#include <linux/vfs.h>
17#include <linux/writeback.h>
18#include <linux/uio.h>
19#include <asm/uaccess.h>
20#include "bfs.h"
21
22MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
23MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
24MODULE_LICENSE("GPL");
25
26#undef DEBUG
27
28#ifdef DEBUG
29#define dprintf(x...) printf(x)
30#else
31#define dprintf(x...)
32#endif
33
34struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
35{
36 struct bfs_inode *di;
37 struct inode *inode;
38 struct buffer_head *bh;
39 int block, off;
40
41 inode = iget_locked(sb, ino);
42 if (!inode)
43 return ERR_PTR(-ENOMEM);
44 if (!(inode->i_state & I_NEW))
45 return inode;
46
47 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
48 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
49 goto error;
50 }
51
52 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
53 bh = sb_bread(inode->i_sb, block);
54 if (!bh) {
55 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
56 ino);
57 goto error;
58 }
59
60 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
61 di = (struct bfs_inode *)bh->b_data + off;
62
63 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
64 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
65 inode->i_mode |= S_IFDIR;
66 inode->i_op = &bfs_dir_inops;
67 inode->i_fop = &bfs_dir_operations;
68 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
69 inode->i_mode |= S_IFREG;
70 inode->i_op = &bfs_file_inops;
71 inode->i_fop = &bfs_file_operations;
72 inode->i_mapping->a_ops = &bfs_aops;
73 }
74
75 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock);
76 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock);
77 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
78 i_uid_write(inode, le32_to_cpu(di->i_uid));
79 i_gid_write(inode, le32_to_cpu(di->i_gid));
80 set_nlink(inode, le32_to_cpu(di->i_nlink));
81 inode->i_size = BFS_FILESIZE(di);
82 inode->i_blocks = BFS_FILEBLOCKS(di);
83 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime);
84 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime);
85 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime);
86 inode->i_atime.tv_nsec = 0;
87 inode->i_mtime.tv_nsec = 0;
88 inode->i_ctime.tv_nsec = 0;
89
90 brelse(bh);
91 unlock_new_inode(inode);
92 return inode;
93
94error:
95 iget_failed(inode);
96 return ERR_PTR(-EIO);
97}
98
99static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p)
100{
101 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) {
102 printf("Bad inode number %s:%08x\n", sb->s_id, ino);
103 return ERR_PTR(-EIO);
104 }
105
106 ino -= BFS_ROOT_INO;
107
108 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
109 if (!*p) {
110 printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
111 return ERR_PTR(-EIO);
112 }
113
114 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK;
115}
116
117static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc)
118{
119 struct bfs_sb_info *info = BFS_SB(inode->i_sb);
120 unsigned int ino = (u16)inode->i_ino;
121 unsigned long i_sblock;
122 struct bfs_inode *di;
123 struct buffer_head *bh;
124 int err = 0;
125
126 dprintf("ino=%08x\n", ino);
127
128 di = find_inode(inode->i_sb, ino, &bh);
129 if (IS_ERR(di))
130 return PTR_ERR(di);
131
132 mutex_lock(&info->bfs_lock);
133
134 if (ino == BFS_ROOT_INO)
135 di->i_vtype = cpu_to_le32(BFS_VDIR);
136 else
137 di->i_vtype = cpu_to_le32(BFS_VREG);
138
139 di->i_ino = cpu_to_le16(ino);
140 di->i_mode = cpu_to_le32(inode->i_mode);
141 di->i_uid = cpu_to_le32(i_uid_read(inode));
142 di->i_gid = cpu_to_le32(i_gid_read(inode));
143 di->i_nlink = cpu_to_le32(inode->i_nlink);
144 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
145 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
146 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
147 i_sblock = BFS_I(inode)->i_sblock;
148 di->i_sblock = cpu_to_le32(i_sblock);
149 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
150 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
151
152 mark_buffer_dirty(bh);
153 if (wbc->sync_mode == WB_SYNC_ALL) {
154 sync_dirty_buffer(bh);
155 if (buffer_req(bh) && !buffer_uptodate(bh))
156 err = -EIO;
157 }
158 brelse(bh);
159 mutex_unlock(&info->bfs_lock);
160 return err;
161}
162
163static void bfs_evict_inode(struct inode *inode)
164{
165 unsigned long ino = inode->i_ino;
166 struct bfs_inode *di;
167 struct buffer_head *bh;
168 struct super_block *s = inode->i_sb;
169 struct bfs_sb_info *info = BFS_SB(s);
170 struct bfs_inode_info *bi = BFS_I(inode);
171
172 dprintf("ino=%08lx\n", ino);
173
174 truncate_inode_pages_final(&inode->i_data);
175 invalidate_inode_buffers(inode);
176 clear_inode(inode);
177
178 if (inode->i_nlink)
179 return;
180
181 di = find_inode(s, inode->i_ino, &bh);
182 if (IS_ERR(di))
183 return;
184
185 mutex_lock(&info->bfs_lock);
186
187 memset(di, 0, sizeof(struct bfs_inode));
188 mark_buffer_dirty(bh);
189 brelse(bh);
190
191 if (bi->i_dsk_ino) {
192 if (bi->i_sblock)
193 info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
194 info->si_freei++;
195 clear_bit(ino, info->si_imap);
196 bfs_dump_imap("delete_inode", s);
197 }
198
199
200
201
202
203
204 if (info->si_lf_eblk == bi->i_eblock)
205 info->si_lf_eblk = bi->i_sblock - 1;
206 mutex_unlock(&info->bfs_lock);
207}
208
209static void bfs_put_super(struct super_block *s)
210{
211 struct bfs_sb_info *info = BFS_SB(s);
212
213 if (!info)
214 return;
215
216 mutex_destroy(&info->bfs_lock);
217 kfree(info->si_imap);
218 kfree(info);
219 s->s_fs_info = NULL;
220}
221
222static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
223{
224 struct super_block *s = dentry->d_sb;
225 struct bfs_sb_info *info = BFS_SB(s);
226 u64 id = huge_encode_dev(s->s_bdev->bd_dev);
227 buf->f_type = BFS_MAGIC;
228 buf->f_bsize = s->s_blocksize;
229 buf->f_blocks = info->si_blocks;
230 buf->f_bfree = buf->f_bavail = info->si_freeb;
231 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
232 buf->f_ffree = info->si_freei;
233 buf->f_fsid.val[0] = (u32)id;
234 buf->f_fsid.val[1] = (u32)(id >> 32);
235 buf->f_namelen = BFS_NAMELEN;
236 return 0;
237}
238
239static struct kmem_cache *bfs_inode_cachep;
240
241static struct inode *bfs_alloc_inode(struct super_block *sb)
242{
243 struct bfs_inode_info *bi;
244 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
245 if (!bi)
246 return NULL;
247 return &bi->vfs_inode;
248}
249
250static void bfs_i_callback(struct rcu_head *head)
251{
252 struct inode *inode = container_of(head, struct inode, i_rcu);
253 kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
254}
255
256static void bfs_destroy_inode(struct inode *inode)
257{
258 call_rcu(&inode->i_rcu, bfs_i_callback);
259}
260
261static void init_once(void *foo)
262{
263 struct bfs_inode_info *bi = foo;
264
265 inode_init_once(&bi->vfs_inode);
266}
267
268static int __init init_inodecache(void)
269{
270 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
271 sizeof(struct bfs_inode_info),
272 0, (SLAB_RECLAIM_ACCOUNT|
273 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
274 init_once);
275 if (bfs_inode_cachep == NULL)
276 return -ENOMEM;
277 return 0;
278}
279
280static void destroy_inodecache(void)
281{
282
283
284
285
286 rcu_barrier();
287 kmem_cache_destroy(bfs_inode_cachep);
288}
289
290static const struct super_operations bfs_sops = {
291 .alloc_inode = bfs_alloc_inode,
292 .destroy_inode = bfs_destroy_inode,
293 .write_inode = bfs_write_inode,
294 .evict_inode = bfs_evict_inode,
295 .put_super = bfs_put_super,
296 .statfs = bfs_statfs,
297};
298
299void bfs_dump_imap(const char *prefix, struct super_block *s)
300{
301#ifdef DEBUG
302 int i;
303 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
304
305 if (!tmpbuf)
306 return;
307 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
308 if (i > PAGE_SIZE - 100) break;
309 if (test_bit(i, BFS_SB(s)->si_imap))
310 strcat(tmpbuf, "1");
311 else
312 strcat(tmpbuf, "0");
313 }
314 printf("BFS-fs: %s: lasti=%08lx <%s>\n",
315 prefix, BFS_SB(s)->si_lasti, tmpbuf);
316 free_page((unsigned long)tmpbuf);
317#endif
318}
319
320static int bfs_fill_super(struct super_block *s, void *data, int silent)
321{
322 struct buffer_head *bh, *sbh;
323 struct bfs_super_block *bfs_sb;
324 struct inode *inode;
325 unsigned i, imap_len;
326 struct bfs_sb_info *info;
327 int ret = -EINVAL;
328 unsigned long i_sblock, i_eblock, i_eoff, s_size;
329
330 info = kzalloc(sizeof(*info), GFP_KERNEL);
331 if (!info)
332 return -ENOMEM;
333 mutex_init(&info->bfs_lock);
334 s->s_fs_info = info;
335
336 sb_set_blocksize(s, BFS_BSIZE);
337
338 sbh = sb_bread(s, 0);
339 if (!sbh)
340 goto out;
341 bfs_sb = (struct bfs_super_block *)sbh->b_data;
342 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
343 if (!silent)
344 printf("No BFS filesystem on %s (magic=%08x)\n",
345 s->s_id, le32_to_cpu(bfs_sb->s_magic));
346 goto out1;
347 }
348 if (BFS_UNCLEAN(bfs_sb, s) && !silent)
349 printf("%s is unclean, continuing\n", s->s_id);
350
351 s->s_magic = BFS_MAGIC;
352
353 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
354 printf("Superblock is corrupted\n");
355 goto out1;
356 }
357
358 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
359 sizeof(struct bfs_inode)
360 + BFS_ROOT_INO - 1;
361 imap_len = (info->si_lasti / 8) + 1;
362 info->si_imap = kzalloc(imap_len, GFP_KERNEL);
363 if (!info->si_imap)
364 goto out1;
365 for (i = 0; i < BFS_ROOT_INO; i++)
366 set_bit(i, info->si_imap);
367
368 s->s_op = &bfs_sops;
369 inode = bfs_iget(s, BFS_ROOT_INO);
370 if (IS_ERR(inode)) {
371 ret = PTR_ERR(inode);
372 goto out2;
373 }
374 s->s_root = d_make_root(inode);
375 if (!s->s_root) {
376 ret = -ENOMEM;
377 goto out2;
378 }
379
380 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
381 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
382 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
383 info->si_freei = 0;
384 info->si_lf_eblk = 0;
385
386
387 bh = sb_bread(s, info->si_blocks - 1);
388 if (!bh) {
389 printf("Last block not available: %lu\n", info->si_blocks - 1);
390 ret = -EIO;
391 goto out3;
392 }
393 brelse(bh);
394
395 bh = NULL;
396 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
397 struct bfs_inode *di;
398 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
399 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
400 unsigned long eblock;
401
402 if (!off) {
403 brelse(bh);
404 bh = sb_bread(s, block);
405 }
406
407 if (!bh)
408 continue;
409
410 di = (struct bfs_inode *)bh->b_data + off;
411
412
413
414 i_eoff = le32_to_cpu(di->i_eoffset);
415 i_sblock = le32_to_cpu(di->i_sblock);
416 i_eblock = le32_to_cpu(di->i_eblock);
417 s_size = le32_to_cpu(bfs_sb->s_end);
418
419 if (i_sblock > info->si_blocks ||
420 i_eblock > info->si_blocks ||
421 i_sblock > i_eblock ||
422 i_eoff > s_size ||
423 i_sblock * BFS_BSIZE > i_eoff) {
424
425 printf("Inode 0x%08x corrupted\n", i);
426
427 brelse(bh);
428 ret = -EIO;
429 goto out3;
430 }
431
432 if (!di->i_ino) {
433 info->si_freei++;
434 continue;
435 }
436 set_bit(i, info->si_imap);
437 info->si_freeb -= BFS_FILEBLOCKS(di);
438
439 eblock = le32_to_cpu(di->i_eblock);
440 if (eblock > info->si_lf_eblk)
441 info->si_lf_eblk = eblock;
442 }
443 brelse(bh);
444 brelse(sbh);
445 bfs_dump_imap("read_super", s);
446 return 0;
447
448out3:
449 dput(s->s_root);
450 s->s_root = NULL;
451out2:
452 kfree(info->si_imap);
453out1:
454 brelse(sbh);
455out:
456 mutex_destroy(&info->bfs_lock);
457 kfree(info);
458 s->s_fs_info = NULL;
459 return ret;
460}
461
462static struct dentry *bfs_mount(struct file_system_type *fs_type,
463 int flags, const char *dev_name, void *data)
464{
465 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
466}
467
468static struct file_system_type bfs_fs_type = {
469 .owner = THIS_MODULE,
470 .name = "bfs",
471 .mount = bfs_mount,
472 .kill_sb = kill_block_super,
473 .fs_flags = FS_REQUIRES_DEV,
474};
475MODULE_ALIAS_FS("bfs");
476
477static int __init init_bfs_fs(void)
478{
479 int err = init_inodecache();
480 if (err)
481 goto out1;
482 err = register_filesystem(&bfs_fs_type);
483 if (err)
484 goto out;
485 return 0;
486out:
487 destroy_inodecache();
488out1:
489 return err;
490}
491
492static void __exit exit_bfs_fs(void)
493{
494 unregister_filesystem(&bfs_fs_type);
495 destroy_inodecache();
496}
497
498module_init(init_bfs_fs)
499module_exit(exit_bfs_fs)
500
