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Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * fs/bfs/dir.c | |
3 | * BFS directory operations. | |
4 | * Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com> | |
fac92bec | 5 | * Made endianness-clean by Andrew Stribblehill <ads@wompom.org> 2005 |
1da177e4 LT |
6 | */ |
7 | ||
8 | #include <linux/time.h> | |
9 | #include <linux/string.h> | |
10 | #include <linux/fs.h> | |
1da177e4 LT |
11 | #include <linux/buffer_head.h> |
12 | #include <linux/sched.h> | |
13 | #include "bfs.h" | |
14 | ||
15 | #undef DEBUG | |
16 | ||
17 | #ifdef DEBUG | |
18 | #define dprintf(x...) printf(x) | |
19 | #else | |
20 | #define dprintf(x...) | |
21 | #endif | |
22 | ||
f433dc56 DV |
23 | static int bfs_add_entry(struct inode *dir, const unsigned char *name, |
24 | int namelen, int ino); | |
25 | static struct buffer_head *bfs_find_entry(struct inode *dir, | |
26 | const unsigned char *name, int namelen, | |
27 | struct bfs_dirent **res_dir); | |
1da177e4 | 28 | |
81b9f66e | 29 | static int bfs_readdir(struct file *f, struct dir_context *ctx) |
1da177e4 | 30 | { |
496ad9aa | 31 | struct inode *dir = file_inode(f); |
f433dc56 DV |
32 | struct buffer_head *bh; |
33 | struct bfs_dirent *de; | |
1da177e4 LT |
34 | unsigned int offset; |
35 | int block; | |
36 | ||
81b9f66e | 37 | if (ctx->pos & (BFS_DIRENT_SIZE - 1)) { |
f433dc56 | 38 | printf("Bad f_pos=%08lx for %s:%08lx\n", |
81b9f66e | 39 | (unsigned long)ctx->pos, |
f433dc56 | 40 | dir->i_sb->s_id, dir->i_ino); |
81b9f66e | 41 | return -EINVAL; |
1da177e4 LT |
42 | } |
43 | ||
81b9f66e AV |
44 | while (ctx->pos < dir->i_size) { |
45 | offset = ctx->pos & (BFS_BSIZE - 1); | |
46 | block = BFS_I(dir)->i_sblock + (ctx->pos >> BFS_BSIZE_BITS); | |
1da177e4 LT |
47 | bh = sb_bread(dir->i_sb, block); |
48 | if (!bh) { | |
81b9f66e | 49 | ctx->pos += BFS_BSIZE - offset; |
1da177e4 LT |
50 | continue; |
51 | } | |
52 | do { | |
53 | de = (struct bfs_dirent *)(bh->b_data + offset); | |
54 | if (de->ino) { | |
55 | int size = strnlen(de->name, BFS_NAMELEN); | |
81b9f66e | 56 | if (!dir_emit(ctx, de->name, size, |
f433dc56 | 57 | le16_to_cpu(de->ino), |
81b9f66e | 58 | DT_UNKNOWN)) { |
1da177e4 | 59 | brelse(bh); |
1da177e4 LT |
60 | return 0; |
61 | } | |
62 | } | |
63 | offset += BFS_DIRENT_SIZE; | |
81b9f66e AV |
64 | ctx->pos += BFS_DIRENT_SIZE; |
65 | } while ((offset < BFS_BSIZE) && (ctx->pos < dir->i_size)); | |
1da177e4 LT |
66 | brelse(bh); |
67 | } | |
81b9f66e | 68 | return 0; |
1da177e4 LT |
69 | } |
70 | ||
4b6f5d20 | 71 | const struct file_operations bfs_dir_operations = { |
1da177e4 | 72 | .read = generic_read_dir, |
c51da20c | 73 | .iterate_shared = bfs_readdir, |
1b061d92 | 74 | .fsync = generic_file_fsync, |
3222a3e5 | 75 | .llseek = generic_file_llseek, |
1da177e4 LT |
76 | }; |
77 | ||
4acdaf27 | 78 | static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
ebfc3b49 | 79 | bool excl) |
1da177e4 LT |
80 | { |
81 | int err; | |
f433dc56 DV |
82 | struct inode *inode; |
83 | struct super_block *s = dir->i_sb; | |
84 | struct bfs_sb_info *info = BFS_SB(s); | |
1da177e4 LT |
85 | unsigned long ino; |
86 | ||
87 | inode = new_inode(s); | |
88 | if (!inode) | |
c3fe5872 | 89 | return -ENOMEM; |
3f165e4c | 90 | mutex_lock(&info->bfs_lock); |
69b195be | 91 | ino = find_first_zero_bit(info->si_imap, info->si_lasti + 1); |
1da177e4 | 92 | if (ino > info->si_lasti) { |
3f165e4c | 93 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
94 | iput(inode); |
95 | return -ENOSPC; | |
96 | } | |
f433dc56 | 97 | set_bit(ino, info->si_imap); |
1da177e4 | 98 | info->si_freei--; |
e6ecdc70 | 99 | inode_init_owner(inode, dir, mode); |
02027d42 | 100 | inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); |
ba52de12 | 101 | inode->i_blocks = 0; |
1da177e4 LT |
102 | inode->i_op = &bfs_file_inops; |
103 | inode->i_fop = &bfs_file_operations; | |
104 | inode->i_mapping->a_ops = &bfs_aops; | |
1da177e4 | 105 | inode->i_ino = ino; |
ce0fe7e7 | 106 | BFS_I(inode)->i_dsk_ino = ino; |
1da177e4 LT |
107 | BFS_I(inode)->i_sblock = 0; |
108 | BFS_I(inode)->i_eblock = 0; | |
109 | insert_inode_hash(inode); | |
110 | mark_inode_dirty(inode); | |
1da85fdf | 111 | bfs_dump_imap("create", s); |
1da177e4 | 112 | |
f433dc56 DV |
113 | err = bfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len, |
114 | inode->i_ino); | |
1da177e4 | 115 | if (err) { |
9a53c3a7 | 116 | inode_dec_link_count(inode); |
3f165e4c | 117 | mutex_unlock(&info->bfs_lock); |
1558182f | 118 | iput(inode); |
1da177e4 LT |
119 | return err; |
120 | } | |
3f165e4c | 121 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
122 | d_instantiate(dentry, inode); |
123 | return 0; | |
124 | } | |
125 | ||
f433dc56 | 126 | static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 127 | unsigned int flags) |
1da177e4 | 128 | { |
f433dc56 DV |
129 | struct inode *inode = NULL; |
130 | struct buffer_head *bh; | |
131 | struct bfs_dirent *de; | |
3f165e4c | 132 | struct bfs_sb_info *info = BFS_SB(dir->i_sb); |
1da177e4 LT |
133 | |
134 | if (dentry->d_name.len > BFS_NAMELEN) | |
135 | return ERR_PTR(-ENAMETOOLONG); | |
136 | ||
3f165e4c | 137 | mutex_lock(&info->bfs_lock); |
1da177e4 LT |
138 | bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); |
139 | if (bh) { | |
fac92bec | 140 | unsigned long ino = (unsigned long)le16_to_cpu(de->ino); |
1da177e4 | 141 | brelse(bh); |
e33ab086 DH |
142 | inode = bfs_iget(dir->i_sb, ino); |
143 | if (IS_ERR(inode)) { | |
3f165e4c | 144 | mutex_unlock(&info->bfs_lock); |
e33ab086 | 145 | return ERR_CAST(inode); |
1da177e4 LT |
146 | } |
147 | } | |
3f165e4c | 148 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
149 | d_add(dentry, inode); |
150 | return NULL; | |
151 | } | |
152 | ||
f433dc56 DV |
153 | static int bfs_link(struct dentry *old, struct inode *dir, |
154 | struct dentry *new) | |
1da177e4 | 155 | { |
2b0143b5 | 156 | struct inode *inode = d_inode(old); |
3f165e4c | 157 | struct bfs_sb_info *info = BFS_SB(inode->i_sb); |
1da177e4 LT |
158 | int err; |
159 | ||
3f165e4c | 160 | mutex_lock(&info->bfs_lock); |
f433dc56 DV |
161 | err = bfs_add_entry(dir, new->d_name.name, new->d_name.len, |
162 | inode->i_ino); | |
1da177e4 | 163 | if (err) { |
3f165e4c | 164 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
165 | return err; |
166 | } | |
d8c76e6f | 167 | inc_nlink(inode); |
02027d42 | 168 | inode->i_ctime = current_time(inode); |
1da177e4 | 169 | mark_inode_dirty(inode); |
7de9c6ee | 170 | ihold(inode); |
1da177e4 | 171 | d_instantiate(new, inode); |
3f165e4c | 172 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
173 | return 0; |
174 | } | |
175 | ||
f433dc56 | 176 | static int bfs_unlink(struct inode *dir, struct dentry *dentry) |
1da177e4 LT |
177 | { |
178 | int error = -ENOENT; | |
2b0143b5 | 179 | struct inode *inode = d_inode(dentry); |
f433dc56 DV |
180 | struct buffer_head *bh; |
181 | struct bfs_dirent *de; | |
3f165e4c | 182 | struct bfs_sb_info *info = BFS_SB(inode->i_sb); |
1da177e4 | 183 | |
3f165e4c | 184 | mutex_lock(&info->bfs_lock); |
1da177e4 | 185 | bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); |
f433dc56 | 186 | if (!bh || (le16_to_cpu(de->ino) != inode->i_ino)) |
1da177e4 LT |
187 | goto out_brelse; |
188 | ||
189 | if (!inode->i_nlink) { | |
f433dc56 DV |
190 | printf("unlinking non-existent file %s:%lu (nlink=%d)\n", |
191 | inode->i_sb->s_id, inode->i_ino, | |
192 | inode->i_nlink); | |
bfe86848 | 193 | set_nlink(inode, 1); |
1da177e4 LT |
194 | } |
195 | de->ino = 0; | |
4427f0c3 | 196 | mark_buffer_dirty_inode(bh, dir); |
02027d42 | 197 | dir->i_ctime = dir->i_mtime = current_time(dir); |
1da177e4 | 198 | mark_inode_dirty(dir); |
1da177e4 | 199 | inode->i_ctime = dir->i_ctime; |
9a53c3a7 | 200 | inode_dec_link_count(inode); |
1da177e4 LT |
201 | error = 0; |
202 | ||
203 | out_brelse: | |
204 | brelse(bh); | |
3f165e4c | 205 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
206 | return error; |
207 | } | |
208 | ||
f433dc56 | 209 | static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry, |
f03b8ad8 MS |
210 | struct inode *new_dir, struct dentry *new_dentry, |
211 | unsigned int flags) | |
1da177e4 | 212 | { |
f433dc56 DV |
213 | struct inode *old_inode, *new_inode; |
214 | struct buffer_head *old_bh, *new_bh; | |
215 | struct bfs_dirent *old_de, *new_de; | |
3f165e4c | 216 | struct bfs_sb_info *info; |
1da177e4 LT |
217 | int error = -ENOENT; |
218 | ||
f03b8ad8 MS |
219 | if (flags & ~RENAME_NOREPLACE) |
220 | return -EINVAL; | |
221 | ||
1da177e4 | 222 | old_bh = new_bh = NULL; |
2b0143b5 | 223 | old_inode = d_inode(old_dentry); |
1da177e4 LT |
224 | if (S_ISDIR(old_inode->i_mode)) |
225 | return -EINVAL; | |
226 | ||
3f165e4c DV |
227 | info = BFS_SB(old_inode->i_sb); |
228 | ||
229 | mutex_lock(&info->bfs_lock); | |
1da177e4 LT |
230 | old_bh = bfs_find_entry(old_dir, |
231 | old_dentry->d_name.name, | |
232 | old_dentry->d_name.len, &old_de); | |
233 | ||
f433dc56 | 234 | if (!old_bh || (le16_to_cpu(old_de->ino) != old_inode->i_ino)) |
1da177e4 LT |
235 | goto end_rename; |
236 | ||
237 | error = -EPERM; | |
2b0143b5 | 238 | new_inode = d_inode(new_dentry); |
1da177e4 LT |
239 | new_bh = bfs_find_entry(new_dir, |
240 | new_dentry->d_name.name, | |
241 | new_dentry->d_name.len, &new_de); | |
242 | ||
243 | if (new_bh && !new_inode) { | |
244 | brelse(new_bh); | |
245 | new_bh = NULL; | |
246 | } | |
247 | if (!new_bh) { | |
248 | error = bfs_add_entry(new_dir, | |
249 | new_dentry->d_name.name, | |
f433dc56 DV |
250 | new_dentry->d_name.len, |
251 | old_inode->i_ino); | |
1da177e4 LT |
252 | if (error) |
253 | goto end_rename; | |
254 | } | |
255 | old_de->ino = 0; | |
02027d42 | 256 | old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir); |
1da177e4 LT |
257 | mark_inode_dirty(old_dir); |
258 | if (new_inode) { | |
02027d42 | 259 | new_inode->i_ctime = current_time(new_inode); |
9a53c3a7 | 260 | inode_dec_link_count(new_inode); |
1da177e4 | 261 | } |
4427f0c3 | 262 | mark_buffer_dirty_inode(old_bh, old_dir); |
1da177e4 LT |
263 | error = 0; |
264 | ||
265 | end_rename: | |
3f165e4c | 266 | mutex_unlock(&info->bfs_lock); |
1da177e4 LT |
267 | brelse(old_bh); |
268 | brelse(new_bh); | |
269 | return error; | |
270 | } | |
271 | ||
754661f1 | 272 | const struct inode_operations bfs_dir_inops = { |
1da177e4 LT |
273 | .create = bfs_create, |
274 | .lookup = bfs_lookup, | |
275 | .link = bfs_link, | |
276 | .unlink = bfs_unlink, | |
277 | .rename = bfs_rename, | |
278 | }; | |
279 | ||
f433dc56 DV |
280 | static int bfs_add_entry(struct inode *dir, const unsigned char *name, |
281 | int namelen, int ino) | |
1da177e4 | 282 | { |
f433dc56 DV |
283 | struct buffer_head *bh; |
284 | struct bfs_dirent *de; | |
285 | int block, sblock, eblock, off, pos; | |
1da177e4 LT |
286 | int i; |
287 | ||
288 | dprintf("name=%s, namelen=%d\n", name, namelen); | |
289 | ||
290 | if (!namelen) | |
291 | return -ENOENT; | |
292 | if (namelen > BFS_NAMELEN) | |
293 | return -ENAMETOOLONG; | |
294 | ||
295 | sblock = BFS_I(dir)->i_sblock; | |
296 | eblock = BFS_I(dir)->i_eblock; | |
f433dc56 | 297 | for (block = sblock; block <= eblock; block++) { |
1da177e4 | 298 | bh = sb_bread(dir->i_sb, block); |
f433dc56 | 299 | if (!bh) |
c3fe5872 | 300 | return -EIO; |
f433dc56 | 301 | for (off = 0; off < BFS_BSIZE; off += BFS_DIRENT_SIZE) { |
1da177e4 | 302 | de = (struct bfs_dirent *)(bh->b_data + off); |
1da177e4 | 303 | if (!de->ino) { |
f433dc56 DV |
304 | pos = (block - sblock) * BFS_BSIZE + off; |
305 | if (pos >= dir->i_size) { | |
1da177e4 | 306 | dir->i_size += BFS_DIRENT_SIZE; |
02027d42 | 307 | dir->i_ctime = current_time(dir); |
1da177e4 | 308 | } |
02027d42 | 309 | dir->i_mtime = current_time(dir); |
1da177e4 | 310 | mark_inode_dirty(dir); |
fac92bec | 311 | de->ino = cpu_to_le16((u16)ino); |
f433dc56 DV |
312 | for (i = 0; i < BFS_NAMELEN; i++) |
313 | de->name[i] = | |
314 | (i < namelen) ? name[i] : 0; | |
4427f0c3 | 315 | mark_buffer_dirty_inode(bh, dir); |
1da177e4 LT |
316 | brelse(bh); |
317 | return 0; | |
318 | } | |
319 | } | |
320 | brelse(bh); | |
321 | } | |
322 | return -ENOSPC; | |
323 | } | |
324 | ||
f433dc56 DV |
325 | static inline int bfs_namecmp(int len, const unsigned char *name, |
326 | const char *buffer) | |
1da177e4 | 327 | { |
f433dc56 | 328 | if ((len < BFS_NAMELEN) && buffer[len]) |
1da177e4 LT |
329 | return 0; |
330 | return !memcmp(name, buffer, len); | |
331 | } | |
332 | ||
f433dc56 DV |
333 | static struct buffer_head *bfs_find_entry(struct inode *dir, |
334 | const unsigned char *name, int namelen, | |
335 | struct bfs_dirent **res_dir) | |
1da177e4 | 336 | { |
f433dc56 DV |
337 | unsigned long block = 0, offset = 0; |
338 | struct buffer_head *bh = NULL; | |
339 | struct bfs_dirent *de; | |
1da177e4 LT |
340 | |
341 | *res_dir = NULL; | |
342 | if (namelen > BFS_NAMELEN) | |
343 | return NULL; | |
f433dc56 | 344 | |
1da177e4 LT |
345 | while (block * BFS_BSIZE + offset < dir->i_size) { |
346 | if (!bh) { | |
347 | bh = sb_bread(dir->i_sb, BFS_I(dir)->i_sblock + block); | |
348 | if (!bh) { | |
349 | block++; | |
350 | continue; | |
351 | } | |
352 | } | |
353 | de = (struct bfs_dirent *)(bh->b_data + offset); | |
354 | offset += BFS_DIRENT_SIZE; | |
f433dc56 DV |
355 | if (le16_to_cpu(de->ino) && |
356 | bfs_namecmp(namelen, name, de->name)) { | |
1da177e4 LT |
357 | *res_dir = de; |
358 | return bh; | |
359 | } | |
360 | if (offset < bh->b_size) | |
361 | continue; | |
362 | brelse(bh); | |
363 | bh = NULL; | |
364 | offset = 0; | |
365 | block++; | |
366 | } | |
367 | brelse(bh); | |
368 | return NULL; | |
369 | } |