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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/bfs/dir.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/bfs/dir.c')
-rw-r--r--fs/bfs/dir.c362
1 files changed, 362 insertions, 0 deletions
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c
new file mode 100644
index 000000000000..5a1e5ce057ff
--- /dev/null
+++ b/fs/bfs/dir.c
@@ -0,0 +1,362 @@
1/*
2 * fs/bfs/dir.c
3 * BFS directory operations.
4 * Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
5 */
6
7#include <linux/time.h>
8#include <linux/string.h>
9#include <linux/fs.h>
10#include <linux/smp_lock.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
23static int bfs_add_entry(struct inode * dir, const char * name, int namelen, int ino);
24static struct buffer_head * bfs_find_entry(struct inode * dir,
25 const char * name, int namelen, struct bfs_dirent ** res_dir);
26
27static int bfs_readdir(struct file * f, void * dirent, filldir_t filldir)
28{
29 struct inode * dir = f->f_dentry->d_inode;
30 struct buffer_head * bh;
31 struct bfs_dirent * de;
32 unsigned int offset;
33 int block;
34
35 lock_kernel();
36
37 if (f->f_pos & (BFS_DIRENT_SIZE-1)) {
38 printf("Bad f_pos=%08lx for %s:%08lx\n", (unsigned long)f->f_pos,
39 dir->i_sb->s_id, dir->i_ino);
40 unlock_kernel();
41 return -EBADF;
42 }
43
44 while (f->f_pos < dir->i_size) {
45 offset = f->f_pos & (BFS_BSIZE-1);
46 block = BFS_I(dir)->i_sblock + (f->f_pos >> BFS_BSIZE_BITS);
47 bh = sb_bread(dir->i_sb, block);
48 if (!bh) {
49 f->f_pos += BFS_BSIZE - offset;
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);
56 if (filldir(dirent, de->name, size, f->f_pos, de->ino, DT_UNKNOWN) < 0) {
57 brelse(bh);
58 unlock_kernel();
59 return 0;
60 }
61 }
62 offset += BFS_DIRENT_SIZE;
63 f->f_pos += BFS_DIRENT_SIZE;
64 } while (offset < BFS_BSIZE && f->f_pos < dir->i_size);
65 brelse(bh);
66 }
67
68 unlock_kernel();
69 return 0;
70}
71
72struct file_operations bfs_dir_operations = {
73 .read = generic_read_dir,
74 .readdir = bfs_readdir,
75 .fsync = file_fsync,
76};
77
78extern void dump_imap(const char *, struct super_block *);
79
80static int bfs_create(struct inode * dir, struct dentry * dentry, int mode,
81 struct nameidata *nd)
82{
83 int err;
84 struct inode * inode;
85 struct super_block * s = dir->i_sb;
86 struct bfs_sb_info * info = BFS_SB(s);
87 unsigned long ino;
88
89 inode = new_inode(s);
90 if (!inode)
91 return -ENOSPC;
92 lock_kernel();
93 ino = find_first_zero_bit(info->si_imap, info->si_lasti);
94 if (ino > info->si_lasti) {
95 unlock_kernel();
96 iput(inode);
97 return -ENOSPC;
98 }
99 set_bit(ino, info->si_imap);
100 info->si_freei--;
101 inode->i_uid = current->fsuid;
102 inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current->fsgid;
103 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
104 inode->i_blocks = inode->i_blksize = 0;
105 inode->i_op = &bfs_file_inops;
106 inode->i_fop = &bfs_file_operations;
107 inode->i_mapping->a_ops = &bfs_aops;
108 inode->i_mode = mode;
109 inode->i_ino = ino;
110 BFS_I(inode)->i_dsk_ino = ino;
111 BFS_I(inode)->i_sblock = 0;
112 BFS_I(inode)->i_eblock = 0;
113 insert_inode_hash(inode);
114 mark_inode_dirty(inode);
115 dump_imap("create",s);
116
117 err = bfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len, inode->i_ino);
118 if (err) {
119 inode->i_nlink--;
120 mark_inode_dirty(inode);
121 iput(inode);
122 unlock_kernel();
123 return err;
124 }
125 unlock_kernel();
126 d_instantiate(dentry, inode);
127 return 0;
128}
129
130static struct dentry * bfs_lookup(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
131{
132 struct inode * inode = NULL;
133 struct buffer_head * bh;
134 struct bfs_dirent * de;
135
136 if (dentry->d_name.len > BFS_NAMELEN)
137 return ERR_PTR(-ENAMETOOLONG);
138
139 lock_kernel();
140 bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
141 if (bh) {
142 unsigned long ino = le32_to_cpu(de->ino);
143 brelse(bh);
144 inode = iget(dir->i_sb, ino);
145 if (!inode) {
146 unlock_kernel();
147 return ERR_PTR(-EACCES);
148 }
149 }
150 unlock_kernel();
151 d_add(dentry, inode);
152 return NULL;
153}
154
155static int bfs_link(struct dentry * old, struct inode * dir, struct dentry * new)
156{
157 struct inode * inode = old->d_inode;
158 int err;
159
160 lock_kernel();
161 err = bfs_add_entry(dir, new->d_name.name, new->d_name.len, inode->i_ino);
162 if (err) {
163 unlock_kernel();
164 return err;
165 }
166 inode->i_nlink++;
167 inode->i_ctime = CURRENT_TIME_SEC;
168 mark_inode_dirty(inode);
169 atomic_inc(&inode->i_count);
170 d_instantiate(new, inode);
171 unlock_kernel();
172 return 0;
173}
174
175
176static int bfs_unlink(struct inode * dir, struct dentry * dentry)
177{
178 int error = -ENOENT;
179 struct inode * inode;
180 struct buffer_head * bh;
181 struct bfs_dirent * de;
182
183 inode = dentry->d_inode;
184 lock_kernel();
185 bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
186 if (!bh || de->ino != inode->i_ino)
187 goto out_brelse;
188
189 if (!inode->i_nlink) {
190 printf("unlinking non-existent file %s:%lu (nlink=%d)\n", inode->i_sb->s_id,
191 inode->i_ino, inode->i_nlink);
192 inode->i_nlink = 1;
193 }
194 de->ino = 0;
195 mark_buffer_dirty(bh);
196 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
197 mark_inode_dirty(dir);
198 inode->i_nlink--;
199 inode->i_ctime = dir->i_ctime;
200 mark_inode_dirty(inode);
201 error = 0;
202
203out_brelse:
204 brelse(bh);
205 unlock_kernel();
206 return error;
207}
208
209static int bfs_rename(struct inode * old_dir, struct dentry * old_dentry,
210 struct inode * new_dir, struct dentry * new_dentry)
211{
212 struct inode * old_inode, * new_inode;
213 struct buffer_head * old_bh, * new_bh;
214 struct bfs_dirent * old_de, * new_de;
215 int error = -ENOENT;
216
217 old_bh = new_bh = NULL;
218 old_inode = old_dentry->d_inode;
219 if (S_ISDIR(old_inode->i_mode))
220 return -EINVAL;
221
222 lock_kernel();
223 old_bh = bfs_find_entry(old_dir,
224 old_dentry->d_name.name,
225 old_dentry->d_name.len, &old_de);
226
227 if (!old_bh || old_de->ino != old_inode->i_ino)
228 goto end_rename;
229
230 error = -EPERM;
231 new_inode = new_dentry->d_inode;
232 new_bh = bfs_find_entry(new_dir,
233 new_dentry->d_name.name,
234 new_dentry->d_name.len, &new_de);
235
236 if (new_bh && !new_inode) {
237 brelse(new_bh);
238 new_bh = NULL;
239 }
240 if (!new_bh) {
241 error = bfs_add_entry(new_dir,
242 new_dentry->d_name.name,
243 new_dentry->d_name.len, old_inode->i_ino);
244 if (error)
245 goto end_rename;
246 }
247 old_de->ino = 0;
248 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
249 mark_inode_dirty(old_dir);
250 if (new_inode) {
251 new_inode->i_nlink--;
252 new_inode->i_ctime = CURRENT_TIME_SEC;
253 mark_inode_dirty(new_inode);
254 }
255 mark_buffer_dirty(old_bh);
256 error = 0;
257
258end_rename:
259 unlock_kernel();
260 brelse(old_bh);
261 brelse(new_bh);
262 return error;
263}
264
265struct inode_operations bfs_dir_inops = {
266 .create = bfs_create,
267 .lookup = bfs_lookup,
268 .link = bfs_link,
269 .unlink = bfs_unlink,
270 .rename = bfs_rename,
271};
272
273static int bfs_add_entry(struct inode * dir, const char * name, int namelen, int ino)
274{
275 struct buffer_head * bh;
276 struct bfs_dirent * de;
277 int block, sblock, eblock, off, eoff;
278 int i;
279
280 dprintf("name=%s, namelen=%d\n", name, namelen);
281
282 if (!namelen)
283 return -ENOENT;
284 if (namelen > BFS_NAMELEN)
285 return -ENAMETOOLONG;
286
287 sblock = BFS_I(dir)->i_sblock;
288 eblock = BFS_I(dir)->i_eblock;
289 eoff = dir->i_size % BFS_BSIZE;
290 for (block=sblock; block<=eblock; block++) {
291 bh = sb_bread(dir->i_sb, block);
292 if(!bh)
293 return -ENOSPC;
294 for (off=0; off<BFS_BSIZE; off+=BFS_DIRENT_SIZE) {
295 de = (struct bfs_dirent *)(bh->b_data + off);
296 if (block==eblock && off>=eoff) {
297 /* Do not read/interpret the garbage in the end of eblock. */
298 de->ino = 0;
299 }
300 if (!de->ino) {
301 if ((block-sblock)*BFS_BSIZE + off >= dir->i_size) {
302 dir->i_size += BFS_DIRENT_SIZE;
303 dir->i_ctime = CURRENT_TIME_SEC;
304 }
305 dir->i_mtime = CURRENT_TIME_SEC;
306 mark_inode_dirty(dir);
307 de->ino = ino;
308 for (i=0; i<BFS_NAMELEN; i++)
309 de->name[i] = (i < namelen) ? name[i] : 0;
310 mark_buffer_dirty(bh);
311 brelse(bh);
312 return 0;
313 }
314 }
315 brelse(bh);
316 }
317 return -ENOSPC;
318}
319
320static inline int bfs_namecmp(int len, const char * name, const char * buffer)
321{
322 if (len < BFS_NAMELEN && buffer[len])
323 return 0;
324 return !memcmp(name, buffer, len);
325}
326
327static struct buffer_head * bfs_find_entry(struct inode * dir,
328 const char * name, int namelen, struct bfs_dirent ** res_dir)
329{
330 unsigned long block, offset;
331 struct buffer_head * bh;
332 struct bfs_dirent * de;
333
334 *res_dir = NULL;
335 if (namelen > BFS_NAMELEN)
336 return NULL;
337 bh = NULL;
338 block = offset = 0;
339 while (block * BFS_BSIZE + offset < dir->i_size) {
340 if (!bh) {
341 bh = sb_bread(dir->i_sb, BFS_I(dir)->i_sblock + block);
342 if (!bh) {
343 block++;
344 continue;
345 }
346 }
347 de = (struct bfs_dirent *)(bh->b_data + offset);
348 offset += BFS_DIRENT_SIZE;
349 if (de->ino && bfs_namecmp(namelen, name, de->name)) {
350 *res_dir = de;
351 return bh;
352 }
353 if (offset < bh->b_size)
354 continue;
355 brelse(bh);
356 bh = NULL;
357 offset = 0;
358 block++;
359 }
360 brelse(bh);
361 return NULL;
362}