Root/
1 | /* |
2 | * fs/bfs/dir.c |
3 | * BFS directory operations. |
4 | * Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com> |
5 | * Made endianness-clean by Andrew Stribblehill <ads@wompom.org> 2005 |
6 | */ |
7 | |
8 | #include <linux/time.h> |
9 | #include <linux/string.h> |
10 | #include <linux/fs.h> |
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 | |
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); |
28 | |
29 | static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir) |
30 | { |
31 | struct inode *dir = f->f_path.dentry->d_inode; |
32 | struct buffer_head *bh; |
33 | struct bfs_dirent *de; |
34 | struct bfs_sb_info *info = BFS_SB(dir->i_sb); |
35 | unsigned int offset; |
36 | int block; |
37 | |
38 | mutex_lock(&info->bfs_lock); |
39 | |
40 | if (f->f_pos & (BFS_DIRENT_SIZE - 1)) { |
41 | printf("Bad f_pos=%08lx for %s:%08lx\n", |
42 | (unsigned long)f->f_pos, |
43 | dir->i_sb->s_id, dir->i_ino); |
44 | mutex_unlock(&info->bfs_lock); |
45 | return -EBADF; |
46 | } |
47 | |
48 | while (f->f_pos < dir->i_size) { |
49 | offset = f->f_pos & (BFS_BSIZE - 1); |
50 | block = BFS_I(dir)->i_sblock + (f->f_pos >> BFS_BSIZE_BITS); |
51 | bh = sb_bread(dir->i_sb, block); |
52 | if (!bh) { |
53 | f->f_pos += BFS_BSIZE - offset; |
54 | continue; |
55 | } |
56 | do { |
57 | de = (struct bfs_dirent *)(bh->b_data + offset); |
58 | if (de->ino) { |
59 | int size = strnlen(de->name, BFS_NAMELEN); |
60 | if (filldir(dirent, de->name, size, f->f_pos, |
61 | le16_to_cpu(de->ino), |
62 | DT_UNKNOWN) < 0) { |
63 | brelse(bh); |
64 | mutex_unlock(&info->bfs_lock); |
65 | return 0; |
66 | } |
67 | } |
68 | offset += BFS_DIRENT_SIZE; |
69 | f->f_pos += BFS_DIRENT_SIZE; |
70 | } while ((offset < BFS_BSIZE) && (f->f_pos < dir->i_size)); |
71 | brelse(bh); |
72 | } |
73 | |
74 | mutex_unlock(&info->bfs_lock); |
75 | return 0; |
76 | } |
77 | |
78 | const struct file_operations bfs_dir_operations = { |
79 | .read = generic_read_dir, |
80 | .readdir = bfs_readdir, |
81 | .fsync = simple_fsync, |
82 | .llseek = generic_file_llseek, |
83 | }; |
84 | |
85 | extern void dump_imap(const char *, struct super_block *); |
86 | |
87 | static int bfs_create(struct inode *dir, struct dentry *dentry, int mode, |
88 | struct nameidata *nd) |
89 | { |
90 | int err; |
91 | struct inode *inode; |
92 | struct super_block *s = dir->i_sb; |
93 | struct bfs_sb_info *info = BFS_SB(s); |
94 | unsigned long ino; |
95 | |
96 | inode = new_inode(s); |
97 | if (!inode) |
98 | return -ENOSPC; |
99 | mutex_lock(&info->bfs_lock); |
100 | ino = find_first_zero_bit(info->si_imap, info->si_lasti); |
101 | if (ino > info->si_lasti) { |
102 | mutex_unlock(&info->bfs_lock); |
103 | iput(inode); |
104 | return -ENOSPC; |
105 | } |
106 | set_bit(ino, info->si_imap); |
107 | info->si_freei--; |
108 | inode->i_uid = current_fsuid(); |
109 | inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current_fsgid(); |
110 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; |
111 | inode->i_blocks = 0; |
112 | inode->i_op = &bfs_file_inops; |
113 | inode->i_fop = &bfs_file_operations; |
114 | inode->i_mapping->a_ops = &bfs_aops; |
115 | inode->i_mode = mode; |
116 | inode->i_ino = ino; |
117 | BFS_I(inode)->i_dsk_ino = ino; |
118 | BFS_I(inode)->i_sblock = 0; |
119 | BFS_I(inode)->i_eblock = 0; |
120 | insert_inode_hash(inode); |
121 | mark_inode_dirty(inode); |
122 | dump_imap("create", s); |
123 | |
124 | err = bfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len, |
125 | inode->i_ino); |
126 | if (err) { |
127 | inode_dec_link_count(inode); |
128 | mutex_unlock(&info->bfs_lock); |
129 | iput(inode); |
130 | return err; |
131 | } |
132 | mutex_unlock(&info->bfs_lock); |
133 | d_instantiate(dentry, inode); |
134 | return 0; |
135 | } |
136 | |
137 | static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry, |
138 | struct nameidata *nd) |
139 | { |
140 | struct inode *inode = NULL; |
141 | struct buffer_head *bh; |
142 | struct bfs_dirent *de; |
143 | struct bfs_sb_info *info = BFS_SB(dir->i_sb); |
144 | |
145 | if (dentry->d_name.len > BFS_NAMELEN) |
146 | return ERR_PTR(-ENAMETOOLONG); |
147 | |
148 | mutex_lock(&info->bfs_lock); |
149 | bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); |
150 | if (bh) { |
151 | unsigned long ino = (unsigned long)le16_to_cpu(de->ino); |
152 | brelse(bh); |
153 | inode = bfs_iget(dir->i_sb, ino); |
154 | if (IS_ERR(inode)) { |
155 | mutex_unlock(&info->bfs_lock); |
156 | return ERR_CAST(inode); |
157 | } |
158 | } |
159 | mutex_unlock(&info->bfs_lock); |
160 | d_add(dentry, inode); |
161 | return NULL; |
162 | } |
163 | |
164 | static int bfs_link(struct dentry *old, struct inode *dir, |
165 | struct dentry *new) |
166 | { |
167 | struct inode *inode = old->d_inode; |
168 | struct bfs_sb_info *info = BFS_SB(inode->i_sb); |
169 | int err; |
170 | |
171 | mutex_lock(&info->bfs_lock); |
172 | err = bfs_add_entry(dir, new->d_name.name, new->d_name.len, |
173 | inode->i_ino); |
174 | if (err) { |
175 | mutex_unlock(&info->bfs_lock); |
176 | return err; |
177 | } |
178 | inc_nlink(inode); |
179 | inode->i_ctime = CURRENT_TIME_SEC; |
180 | mark_inode_dirty(inode); |
181 | atomic_inc(&inode->i_count); |
182 | d_instantiate(new, inode); |
183 | mutex_unlock(&info->bfs_lock); |
184 | return 0; |
185 | } |
186 | |
187 | static int bfs_unlink(struct inode *dir, struct dentry *dentry) |
188 | { |
189 | int error = -ENOENT; |
190 | struct inode *inode = dentry->d_inode; |
191 | struct buffer_head *bh; |
192 | struct bfs_dirent *de; |
193 | struct bfs_sb_info *info = BFS_SB(inode->i_sb); |
194 | |
195 | mutex_lock(&info->bfs_lock); |
196 | bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); |
197 | if (!bh || (le16_to_cpu(de->ino) != inode->i_ino)) |
198 | goto out_brelse; |
199 | |
200 | if (!inode->i_nlink) { |
201 | printf("unlinking non-existent file %s:%lu (nlink=%d)\n", |
202 | inode->i_sb->s_id, inode->i_ino, |
203 | inode->i_nlink); |
204 | inode->i_nlink = 1; |
205 | } |
206 | de->ino = 0; |
207 | mark_buffer_dirty_inode(bh, dir); |
208 | dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; |
209 | mark_inode_dirty(dir); |
210 | inode->i_ctime = dir->i_ctime; |
211 | inode_dec_link_count(inode); |
212 | error = 0; |
213 | |
214 | out_brelse: |
215 | brelse(bh); |
216 | mutex_unlock(&info->bfs_lock); |
217 | return error; |
218 | } |
219 | |
220 | static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry, |
221 | struct inode *new_dir, struct dentry *new_dentry) |
222 | { |
223 | struct inode *old_inode, *new_inode; |
224 | struct buffer_head *old_bh, *new_bh; |
225 | struct bfs_dirent *old_de, *new_de; |
226 | struct bfs_sb_info *info; |
227 | int error = -ENOENT; |
228 | |
229 | old_bh = new_bh = NULL; |
230 | old_inode = old_dentry->d_inode; |
231 | if (S_ISDIR(old_inode->i_mode)) |
232 | return -EINVAL; |
233 | |
234 | info = BFS_SB(old_inode->i_sb); |
235 | |
236 | mutex_lock(&info->bfs_lock); |
237 | old_bh = bfs_find_entry(old_dir, |
238 | old_dentry->d_name.name, |
239 | old_dentry->d_name.len, &old_de); |
240 | |
241 | if (!old_bh || (le16_to_cpu(old_de->ino) != old_inode->i_ino)) |
242 | goto end_rename; |
243 | |
244 | error = -EPERM; |
245 | new_inode = new_dentry->d_inode; |
246 | new_bh = bfs_find_entry(new_dir, |
247 | new_dentry->d_name.name, |
248 | new_dentry->d_name.len, &new_de); |
249 | |
250 | if (new_bh && !new_inode) { |
251 | brelse(new_bh); |
252 | new_bh = NULL; |
253 | } |
254 | if (!new_bh) { |
255 | error = bfs_add_entry(new_dir, |
256 | new_dentry->d_name.name, |
257 | new_dentry->d_name.len, |
258 | old_inode->i_ino); |
259 | if (error) |
260 | goto end_rename; |
261 | } |
262 | old_de->ino = 0; |
263 | old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; |
264 | mark_inode_dirty(old_dir); |
265 | if (new_inode) { |
266 | new_inode->i_ctime = CURRENT_TIME_SEC; |
267 | inode_dec_link_count(new_inode); |
268 | } |
269 | mark_buffer_dirty_inode(old_bh, old_dir); |
270 | error = 0; |
271 | |
272 | end_rename: |
273 | mutex_unlock(&info->bfs_lock); |
274 | brelse(old_bh); |
275 | brelse(new_bh); |
276 | return error; |
277 | } |
278 | |
279 | const struct inode_operations bfs_dir_inops = { |
280 | .create = bfs_create, |
281 | .lookup = bfs_lookup, |
282 | .link = bfs_link, |
283 | .unlink = bfs_unlink, |
284 | .rename = bfs_rename, |
285 | }; |
286 | |
287 | static int bfs_add_entry(struct inode *dir, const unsigned char *name, |
288 | int namelen, int ino) |
289 | { |
290 | struct buffer_head *bh; |
291 | struct bfs_dirent *de; |
292 | int block, sblock, eblock, off, pos; |
293 | int i; |
294 | |
295 | dprintf("name=%s, namelen=%d\n", name, namelen); |
296 | |
297 | if (!namelen) |
298 | return -ENOENT; |
299 | if (namelen > BFS_NAMELEN) |
300 | return -ENAMETOOLONG; |
301 | |
302 | sblock = BFS_I(dir)->i_sblock; |
303 | eblock = BFS_I(dir)->i_eblock; |
304 | for (block = sblock; block <= eblock; block++) { |
305 | bh = sb_bread(dir->i_sb, block); |
306 | if (!bh) |
307 | return -ENOSPC; |
308 | for (off = 0; off < BFS_BSIZE; off += BFS_DIRENT_SIZE) { |
309 | de = (struct bfs_dirent *)(bh->b_data + off); |
310 | if (!de->ino) { |
311 | pos = (block - sblock) * BFS_BSIZE + off; |
312 | if (pos >= dir->i_size) { |
313 | dir->i_size += BFS_DIRENT_SIZE; |
314 | dir->i_ctime = CURRENT_TIME_SEC; |
315 | } |
316 | dir->i_mtime = CURRENT_TIME_SEC; |
317 | mark_inode_dirty(dir); |
318 | de->ino = cpu_to_le16((u16)ino); |
319 | for (i = 0; i < BFS_NAMELEN; i++) |
320 | de->name[i] = |
321 | (i < namelen) ? name[i] : 0; |
322 | mark_buffer_dirty_inode(bh, dir); |
323 | brelse(bh); |
324 | return 0; |
325 | } |
326 | } |
327 | brelse(bh); |
328 | } |
329 | return -ENOSPC; |
330 | } |
331 | |
332 | static inline int bfs_namecmp(int len, const unsigned char *name, |
333 | const char *buffer) |
334 | { |
335 | if ((len < BFS_NAMELEN) && buffer[len]) |
336 | return 0; |
337 | return !memcmp(name, buffer, len); |
338 | } |
339 | |
340 | static struct buffer_head *bfs_find_entry(struct inode *dir, |
341 | const unsigned char *name, int namelen, |
342 | struct bfs_dirent **res_dir) |
343 | { |
344 | unsigned long block = 0, offset = 0; |
345 | struct buffer_head *bh = NULL; |
346 | struct bfs_dirent *de; |
347 | |
348 | *res_dir = NULL; |
349 | if (namelen > BFS_NAMELEN) |
350 | return NULL; |
351 | |
352 | while (block * BFS_BSIZE + offset < dir->i_size) { |
353 | if (!bh) { |
354 | bh = sb_bread(dir->i_sb, BFS_I(dir)->i_sblock + block); |
355 | if (!bh) { |
356 | block++; |
357 | continue; |
358 | } |
359 | } |
360 | de = (struct bfs_dirent *)(bh->b_data + offset); |
361 | offset += BFS_DIRENT_SIZE; |
362 | if (le16_to_cpu(de->ino) && |
363 | bfs_namecmp(namelen, name, de->name)) { |
364 | *res_dir = de; |
365 | return bh; |
366 | } |
367 | if (offset < bh->b_size) |
368 | continue; |
369 | brelse(bh); |
370 | bh = NULL; |
371 | offset = 0; |
372 | block++; |
373 | } |
374 | brelse(bh); |
375 | return NULL; |
376 | } |
377 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9