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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 <linux/uio.h>
19#include <linux/uaccess.h>
20#include "bfs.h"
21
22MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>");
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("evict_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);
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 = u64_to_fsid(id);
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_free_inode(struct inode *inode)
249{
250 kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
251}
252
253static void init_once(void *foo)
254{
255 struct bfs_inode_info *bi = foo;
256
257 inode_init_once(&bi->vfs_inode);
258}
259
260static int __init init_inodecache(void)
261{
262 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
263 sizeof(struct bfs_inode_info),
264 0, (SLAB_RECLAIM_ACCOUNT|
265 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
266 init_once);
267 if (bfs_inode_cachep == NULL)
268 return -ENOMEM;
269 return 0;
270}
271
272static void destroy_inodecache(void)
273{
274
275
276
277
278 rcu_barrier();
279 kmem_cache_destroy(bfs_inode_cachep);
280}
281
282static const struct super_operations bfs_sops = {
283 .alloc_inode = bfs_alloc_inode,
284 .free_inode = bfs_free_inode,
285 .write_inode = bfs_write_inode,
286 .evict_inode = bfs_evict_inode,
287 .put_super = bfs_put_super,
288 .statfs = bfs_statfs,
289};
290
291void bfs_dump_imap(const char *prefix, struct super_block *s)
292{
293#ifdef DEBUG
294 int i;
295 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
296
297 if (!tmpbuf)
298 return;
299 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
300 if (i > PAGE_SIZE - 100) break;
301 if (test_bit(i, BFS_SB(s)->si_imap))
302 strcat(tmpbuf, "1");
303 else
304 strcat(tmpbuf, "0");
305 }
306 printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
307 free_page((unsigned long)tmpbuf);
308#endif
309}
310
311static int bfs_fill_super(struct super_block *s, void *data, int silent)
312{
313 struct buffer_head *bh, *sbh;
314 struct bfs_super_block *bfs_sb;
315 struct inode *inode;
316 unsigned i;
317 struct bfs_sb_info *info;
318 int ret = -EINVAL;
319 unsigned long i_sblock, i_eblock, i_eoff, s_size;
320
321 info = kzalloc(sizeof(*info), GFP_KERNEL);
322 if (!info)
323 return -ENOMEM;
324 mutex_init(&info->bfs_lock);
325 s->s_fs_info = info;
326 s->s_time_min = 0;
327 s->s_time_max = U32_MAX;
328
329 sb_set_blocksize(s, BFS_BSIZE);
330
331 sbh = sb_bread(s, 0);
332 if (!sbh)
333 goto out;
334 bfs_sb = (struct bfs_super_block *)sbh->b_data;
335 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
336 if (!silent)
337 printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id, le32_to_cpu(bfs_sb->s_magic));
338 goto out1;
339 }
340 if (BFS_UNCLEAN(bfs_sb, s) && !silent)
341 printf("%s is unclean, continuing\n", s->s_id);
342
343 s->s_magic = BFS_MAGIC;
344
345 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) ||
346 le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) {
347 printf("Superblock is corrupted on %s\n", s->s_id);
348 goto out1;
349 }
350
351 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1;
352 if (info->si_lasti == BFS_MAX_LASTI)
353 printf("NOTE: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id);
354 else if (info->si_lasti > BFS_MAX_LASTI) {
355 printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id);
356 goto out1;
357 }
358 for (i = 0; i < BFS_ROOT_INO; i++)
359 set_bit(i, info->si_imap);
360
361 s->s_op = &bfs_sops;
362 inode = bfs_iget(s, BFS_ROOT_INO);
363 if (IS_ERR(inode)) {
364 ret = PTR_ERR(inode);
365 goto out1;
366 }
367 s->s_root = d_make_root(inode);
368 if (!s->s_root) {
369 ret = -ENOMEM;
370 goto out1;
371 }
372
373 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
374 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
375 info->si_freei = 0;
376 info->si_lf_eblk = 0;
377
378
379 bh = sb_bread(s, info->si_blocks - 1);
380 if (!bh) {
381 printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1);
382 ret = -EIO;
383 goto out2;
384 }
385 brelse(bh);
386
387 bh = NULL;
388 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
389 struct bfs_inode *di;
390 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
391 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
392 unsigned long eblock;
393
394 if (!off) {
395 brelse(bh);
396 bh = sb_bread(s, block);
397 }
398
399 if (!bh)
400 continue;
401
402 di = (struct bfs_inode *)bh->b_data + off;
403
404
405
406 i_eoff = le32_to_cpu(di->i_eoffset);
407 i_sblock = le32_to_cpu(di->i_sblock);
408 i_eblock = le32_to_cpu(di->i_eblock);
409 s_size = le32_to_cpu(bfs_sb->s_end);
410
411 if (i_sblock > info->si_blocks ||
412 i_eblock > info->si_blocks ||
413 i_sblock > i_eblock ||
414 (i_eoff != le32_to_cpu(-1) && i_eoff > s_size) ||
415 i_sblock * BFS_BSIZE > i_eoff) {
416
417 printf("Inode 0x%08x corrupted on %s\n", i, s->s_id);
418
419 brelse(bh);
420 ret = -EIO;
421 goto out2;
422 }
423
424 if (!di->i_ino) {
425 info->si_freei++;
426 continue;
427 }
428 set_bit(i, info->si_imap);
429 info->si_freeb -= BFS_FILEBLOCKS(di);
430
431 eblock = le32_to_cpu(di->i_eblock);
432 if (eblock > info->si_lf_eblk)
433 info->si_lf_eblk = eblock;
434 }
435 brelse(bh);
436 brelse(sbh);
437 bfs_dump_imap("fill_super", s);
438 return 0;
439
440out2:
441 dput(s->s_root);
442 s->s_root = NULL;
443out1:
444 brelse(sbh);
445out:
446 mutex_destroy(&info->bfs_lock);
447 kfree(info);
448 s->s_fs_info = NULL;
449 return ret;
450}
451
452static struct dentry *bfs_mount(struct file_system_type *fs_type,
453 int flags, const char *dev_name, void *data)
454{
455 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
456}
457
458static struct file_system_type bfs_fs_type = {
459 .owner = THIS_MODULE,
460 .name = "bfs",
461 .mount = bfs_mount,
462 .kill_sb = kill_block_super,
463 .fs_flags = FS_REQUIRES_DEV,
464};
465MODULE_ALIAS_FS("bfs");
466
467static int __init init_bfs_fs(void)
468{
469 int err = init_inodecache();
470 if (err)
471 goto out1;
472 err = register_filesystem(&bfs_fs_type);
473 if (err)
474 goto out;
475 return 0;
476out:
477 destroy_inodecache();
478out1:
479 return err;
480}
481
482static void __exit exit_bfs_fs(void)
483{
484 unregister_filesystem(&bfs_fs_type);
485 destroy_inodecache();
486}
487
488module_init(init_bfs_fs)
489module_exit(exit_bfs_fs)
490
