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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 <asm/uaccess.h>
19#include "bfs.h"
20
21MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
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("delete_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->si_imap);
217 kfree(info);
218 s->s_fs_info = NULL;
219}
220
221static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
222{
223 struct super_block *s = dentry->d_sb;
224 struct bfs_sb_info *info = BFS_SB(s);
225 u64 id = huge_encode_dev(s->s_bdev->bd_dev);
226 buf->f_type = BFS_MAGIC;
227 buf->f_bsize = s->s_blocksize;
228 buf->f_blocks = info->si_blocks;
229 buf->f_bfree = buf->f_bavail = info->si_freeb;
230 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
231 buf->f_ffree = info->si_freei;
232 buf->f_fsid.val[0] = (u32)id;
233 buf->f_fsid.val[1] = (u32)(id >> 32);
234 buf->f_namelen = BFS_NAMELEN;
235 return 0;
236}
237
238static struct kmem_cache *bfs_inode_cachep;
239
240static struct inode *bfs_alloc_inode(struct super_block *sb)
241{
242 struct bfs_inode_info *bi;
243 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
244 if (!bi)
245 return NULL;
246 return &bi->vfs_inode;
247}
248
249static void bfs_i_callback(struct rcu_head *head)
250{
251 struct inode *inode = container_of(head, struct inode, i_rcu);
252 kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
253}
254
255static void bfs_destroy_inode(struct inode *inode)
256{
257 call_rcu(&inode->i_rcu, bfs_i_callback);
258}
259
260static void init_once(void *foo)
261{
262 struct bfs_inode_info *bi = foo;
263
264 inode_init_once(&bi->vfs_inode);
265}
266
267static int __init init_inodecache(void)
268{
269 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
270 sizeof(struct bfs_inode_info),
271 0, (SLAB_RECLAIM_ACCOUNT|
272 SLAB_MEM_SPREAD),
273 init_once);
274 if (bfs_inode_cachep == NULL)
275 return -ENOMEM;
276 return 0;
277}
278
279static void destroy_inodecache(void)
280{
281
282
283
284
285 rcu_barrier();
286 kmem_cache_destroy(bfs_inode_cachep);
287}
288
289static const struct super_operations bfs_sops = {
290 .alloc_inode = bfs_alloc_inode,
291 .destroy_inode = bfs_destroy_inode,
292 .write_inode = bfs_write_inode,
293 .evict_inode = bfs_evict_inode,
294 .put_super = bfs_put_super,
295 .statfs = bfs_statfs,
296};
297
298void bfs_dump_imap(const char *prefix, struct super_block *s)
299{
300#ifdef DEBUG
301 int i;
302 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
303
304 if (!tmpbuf)
305 return;
306 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
307 if (i > PAGE_SIZE - 100) break;
308 if (test_bit(i, BFS_SB(s)->si_imap))
309 strcat(tmpbuf, "1");
310 else
311 strcat(tmpbuf, "0");
312 }
313 printf("BFS-fs: %s: lasti=%08lx <%s>\n",
314 prefix, BFS_SB(s)->si_lasti, tmpbuf);
315 free_page((unsigned long)tmpbuf);
316#endif
317}
318
319static int bfs_fill_super(struct super_block *s, void *data, int silent)
320{
321 struct buffer_head *bh, *sbh;
322 struct bfs_super_block *bfs_sb;
323 struct inode *inode;
324 unsigned i, imap_len;
325 struct bfs_sb_info *info;
326 int ret = -EINVAL;
327 unsigned long i_sblock, i_eblock, i_eoff, s_size;
328
329 info = kzalloc(sizeof(*info), GFP_KERNEL);
330 if (!info)
331 return -ENOMEM;
332 mutex_init(&info->bfs_lock);
333 s->s_fs_info = info;
334
335 sb_set_blocksize(s, BFS_BSIZE);
336
337 sbh = sb_bread(s, 0);
338 if (!sbh)
339 goto out;
340 bfs_sb = (struct bfs_super_block *)sbh->b_data;
341 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
342 if (!silent)
343 printf("No BFS filesystem on %s (magic=%08x)\n",
344 s->s_id, le32_to_cpu(bfs_sb->s_magic));
345 goto out1;
346 }
347 if (BFS_UNCLEAN(bfs_sb, s) && !silent)
348 printf("%s is unclean, continuing\n", s->s_id);
349
350 s->s_magic = BFS_MAGIC;
351
352 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
353 printf("Superblock is corrupted\n");
354 goto out1;
355 }
356
357 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
358 sizeof(struct bfs_inode)
359 + BFS_ROOT_INO - 1;
360 imap_len = (info->si_lasti / 8) + 1;
361 info->si_imap = kzalloc(imap_len, GFP_KERNEL);
362 if (!info->si_imap)
363 goto out1;
364 for (i = 0; i < BFS_ROOT_INO; i++)
365 set_bit(i, info->si_imap);
366
367 s->s_op = &bfs_sops;
368 inode = bfs_iget(s, BFS_ROOT_INO);
369 if (IS_ERR(inode)) {
370 ret = PTR_ERR(inode);
371 goto out2;
372 }
373 s->s_root = d_make_root(inode);
374 if (!s->s_root) {
375 ret = -ENOMEM;
376 goto out2;
377 }
378
379 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
380 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
381 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
382 info->si_freei = 0;
383 info->si_lf_eblk = 0;
384
385
386 bh = sb_bread(s, info->si_blocks - 1);
387 if (!bh) {
388 printf("Last block not available: %lu\n", info->si_blocks - 1);
389 ret = -EIO;
390 goto out3;
391 }
392 brelse(bh);
393
394 bh = NULL;
395 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
396 struct bfs_inode *di;
397 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
398 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
399 unsigned long eblock;
400
401 if (!off) {
402 brelse(bh);
403 bh = sb_bread(s, block);
404 }
405
406 if (!bh)
407 continue;
408
409 di = (struct bfs_inode *)bh->b_data + off;
410
411
412
413 i_eoff = le32_to_cpu(di->i_eoffset);
414 i_sblock = le32_to_cpu(di->i_sblock);
415 i_eblock = le32_to_cpu(di->i_eblock);
416 s_size = le32_to_cpu(bfs_sb->s_end);
417
418 if (i_sblock > info->si_blocks ||
419 i_eblock > info->si_blocks ||
420 i_sblock > i_eblock ||
421 i_eoff > s_size ||
422 i_sblock * BFS_BSIZE > i_eoff) {
423
424 printf("Inode 0x%08x corrupted\n", i);
425
426 brelse(bh);
427 ret = -EIO;
428 goto out3;
429 }
430
431 if (!di->i_ino) {
432 info->si_freei++;
433 continue;
434 }
435 set_bit(i, info->si_imap);
436 info->si_freeb -= BFS_FILEBLOCKS(di);
437
438 eblock = le32_to_cpu(di->i_eblock);
439 if (eblock > info->si_lf_eblk)
440 info->si_lf_eblk = eblock;
441 }
442 brelse(bh);
443 brelse(sbh);
444 bfs_dump_imap("read_super", s);
445 return 0;
446
447out3:
448 dput(s->s_root);
449 s->s_root = NULL;
450out2:
451 kfree(info->si_imap);
452out1:
453 brelse(sbh);
454out:
455 mutex_destroy(&info->bfs_lock);
456 kfree(info);
457 s->s_fs_info = NULL;
458 return ret;
459}
460
461static struct dentry *bfs_mount(struct file_system_type *fs_type,
462 int flags, const char *dev_name, void *data)
463{
464 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
465}
466
467static struct file_system_type bfs_fs_type = {
468 .owner = THIS_MODULE,
469 .name = "bfs",
470 .mount = bfs_mount,
471 .kill_sb = kill_block_super,
472 .fs_flags = FS_REQUIRES_DEV,
473};
474MODULE_ALIAS_FS("bfs");
475
476static int __init init_bfs_fs(void)
477{
478 int err = init_inodecache();
479 if (err)
480 goto out1;
481 err = register_filesystem(&bfs_fs_type);
482 if (err)
483 goto out;
484 return 0;
485out:
486 destroy_inodecache();
487out1:
488 return err;
489}
490
491static void __exit exit_bfs_fs(void)
492{
493 unregister_filesystem(&bfs_fs_type);
494 destroy_inodecache();
495}
496
497module_init(init_bfs_fs)
498module_exit(exit_bfs_fs)
499
