blob: 1e41aadb1068672a1969d6496dce9dd5e930b656 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/bfs/dir.c
3 * BFS directory operations.
4 * Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
Andrew Stribblehillfac92be2005-09-09 13:02:04 -07005 * Made endianness-clean by Andrew Stribblehill <ads@wompom.org> 2005
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 */
7
8#include <linux/time.h>
9#include <linux/string.h>
10#include <linux/fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#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
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080023static int bfs_add_entry(struct inode *dir, const unsigned char *name,
24 int namelen, int ino);
25static struct buffer_head *bfs_find_entry(struct inode *dir,
26 const unsigned char *name, int namelen,
27 struct bfs_dirent **res_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080029static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir)
Linus Torvalds1da177e2005-04-16 15:20:36 -070030{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080031 struct inode *dir = f->f_path.dentry->d_inode;
32 struct buffer_head *bh;
33 struct bfs_dirent *de;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -070034 struct bfs_sb_info *info = BFS_SB(dir->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 unsigned int offset;
36 int block;
37
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -070038 mutex_lock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080040 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);
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -070044 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 return -EBADF;
46 }
47
48 while (f->f_pos < dir->i_size) {
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080049 offset = f->f_pos & (BFS_BSIZE - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070050 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);
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080060 if (filldir(dirent, de->name, size, f->f_pos,
61 le16_to_cpu(de->ino),
62 DT_UNKNOWN) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 brelse(bh);
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -070064 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 return 0;
66 }
67 }
68 offset += BFS_DIRENT_SIZE;
69 f->f_pos += BFS_DIRENT_SIZE;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080070 } while ((offset < BFS_BSIZE) && (f->f_pos < dir->i_size));
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 brelse(bh);
72 }
73
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -070074 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 return 0;
76}
77
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080078const struct file_operations bfs_dir_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 .read = generic_read_dir,
80 .readdir = bfs_readdir,
Al Viro4427f0c2009-06-08 01:15:58 -040081 .fsync = simple_fsync,
Christoph Hellwig3222a3e2008-09-03 21:53:01 +020082 .llseek = generic_file_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -070083};
84
85extern void dump_imap(const char *, struct super_block *);
86
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080087static int bfs_create(struct inode *dir, struct dentry *dentry, int mode,
88 struct nameidata *nd)
Linus Torvalds1da177e2005-04-16 15:20:36 -070089{
90 int err;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -080091 struct inode *inode;
92 struct super_block *s = dir->i_sb;
93 struct bfs_sb_info *info = BFS_SB(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 unsigned long ino;
95
96 inode = new_inode(s);
97 if (!inode)
98 return -ENOSPC;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -070099 mutex_lock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 ino = find_first_zero_bit(info->si_imap, info->si_lasti);
101 if (ino > info->si_lasti) {
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700102 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 iput(inode);
104 return -ENOSPC;
105 }
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800106 set_bit(ino, info->si_imap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 info->si_freei--;
David Howells1109b072008-11-14 10:38:47 +1100108 inode->i_uid = current_fsuid();
109 inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current_fsgid();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
Theodore Ts'oba52de12006-09-27 01:50:49 -0700111 inode->i_blocks = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 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;
Alexey Dobriyance0fe7e2005-10-04 17:43:06 +0100117 BFS_I(inode)->i_dsk_ino = ino;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 BFS_I(inode)->i_sblock = 0;
119 BFS_I(inode)->i_eblock = 0;
120 insert_inode_hash(inode);
121 mark_inode_dirty(inode);
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800122 dump_imap("create", s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800124 err = bfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len,
125 inode->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 if (err) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700127 inode_dec_link_count(inode);
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700128 mutex_unlock(&info->bfs_lock);
Eric Sesterhenn15581822008-09-13 02:33:12 -0700129 iput(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 return err;
131 }
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700132 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 d_instantiate(dentry, inode);
134 return 0;
135}
136
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800137static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry,
138 struct nameidata *nd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800140 struct inode *inode = NULL;
141 struct buffer_head *bh;
142 struct bfs_dirent *de;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700143 struct bfs_sb_info *info = BFS_SB(dir->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
145 if (dentry->d_name.len > BFS_NAMELEN)
146 return ERR_PTR(-ENAMETOOLONG);
147
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700148 mutex_lock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
150 if (bh) {
Andrew Stribblehillfac92be2005-09-09 13:02:04 -0700151 unsigned long ino = (unsigned long)le16_to_cpu(de->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 brelse(bh);
David Howellse33ab082008-02-07 00:15:32 -0800153 inode = bfs_iget(dir->i_sb, ino);
154 if (IS_ERR(inode)) {
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700155 mutex_unlock(&info->bfs_lock);
David Howellse33ab082008-02-07 00:15:32 -0800156 return ERR_CAST(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 }
158 }
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700159 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 d_add(dentry, inode);
161 return NULL;
162}
163
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800164static int bfs_link(struct dentry *old, struct inode *dir,
165 struct dentry *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800167 struct inode *inode = old->d_inode;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700168 struct bfs_sb_info *info = BFS_SB(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 int err;
170
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700171 mutex_lock(&info->bfs_lock);
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800172 err = bfs_add_entry(dir, new->d_name.name, new->d_name.len,
173 inode->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 if (err) {
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700175 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 return err;
177 }
Dave Hansend8c76e62006-09-30 23:29:04 -0700178 inc_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 inode->i_ctime = CURRENT_TIME_SEC;
180 mark_inode_dirty(inode);
181 atomic_inc(&inode->i_count);
182 d_instantiate(new, inode);
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700183 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 return 0;
185}
186
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800187static int bfs_unlink(struct inode *dir, struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188{
189 int error = -ENOENT;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700190 struct inode *inode = dentry->d_inode;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800191 struct buffer_head *bh;
192 struct bfs_dirent *de;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700193 struct bfs_sb_info *info = BFS_SB(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700195 mutex_lock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800197 if (!bh || (le16_to_cpu(de->ino) != inode->i_ino))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 goto out_brelse;
199
200 if (!inode->i_nlink) {
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800201 printf("unlinking non-existent file %s:%lu (nlink=%d)\n",
202 inode->i_sb->s_id, inode->i_ino,
203 inode->i_nlink);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 inode->i_nlink = 1;
205 }
206 de->ino = 0;
Al Viro4427f0c2009-06-08 01:15:58 -0400207 mark_buffer_dirty_inode(bh, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
209 mark_inode_dirty(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 inode->i_ctime = dir->i_ctime;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700211 inode_dec_link_count(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 error = 0;
213
214out_brelse:
215 brelse(bh);
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700216 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 return error;
218}
219
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800220static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
221 struct inode *new_dir, struct dentry *new_dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800223 struct inode *old_inode, *new_inode;
224 struct buffer_head *old_bh, *new_bh;
225 struct bfs_dirent *old_de, *new_de;
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700226 struct bfs_sb_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 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
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700234 info = BFS_SB(old_inode->i_sb);
235
236 mutex_lock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 old_bh = bfs_find_entry(old_dir,
238 old_dentry->d_name.name,
239 old_dentry->d_name.len, &old_de);
240
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800241 if (!old_bh || (le16_to_cpu(old_de->ino) != old_inode->i_ino))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 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,
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800257 new_dentry->d_name.len,
258 old_inode->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 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) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 new_inode->i_ctime = CURRENT_TIME_SEC;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700267 inode_dec_link_count(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 }
Al Viro4427f0c2009-06-08 01:15:58 -0400269 mark_buffer_dirty_inode(old_bh, old_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 error = 0;
271
272end_rename:
Dmitri Vorobiev3f165e42008-07-25 19:44:54 -0700273 mutex_unlock(&info->bfs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 brelse(old_bh);
275 brelse(new_bh);
276 return error;
277}
278
Arjan van de Ven754661f2007-02-12 00:55:38 -0800279const struct inode_operations bfs_dir_inops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 .create = bfs_create,
281 .lookup = bfs_lookup,
282 .link = bfs_link,
283 .unlink = bfs_unlink,
284 .rename = bfs_rename,
285};
286
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800287static int bfs_add_entry(struct inode *dir, const unsigned char *name,
288 int namelen, int ino)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800290 struct buffer_head *bh;
291 struct bfs_dirent *de;
292 int block, sblock, eblock, off, pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 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;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800304 for (block = sblock; block <= eblock; block++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 bh = sb_bread(dir->i_sb, block);
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800306 if (!bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 return -ENOSPC;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800308 for (off = 0; off < BFS_BSIZE; off += BFS_DIRENT_SIZE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 de = (struct bfs_dirent *)(bh->b_data + off);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 if (!de->ino) {
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800311 pos = (block - sblock) * BFS_BSIZE + off;
312 if (pos >= dir->i_size) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 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);
Andrew Stribblehillfac92be2005-09-09 13:02:04 -0700318 de->ino = cpu_to_le16((u16)ino);
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800319 for (i = 0; i < BFS_NAMELEN; i++)
320 de->name[i] =
321 (i < namelen) ? name[i] : 0;
Al Viro4427f0c2009-06-08 01:15:58 -0400322 mark_buffer_dirty_inode(bh, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 brelse(bh);
324 return 0;
325 }
326 }
327 brelse(bh);
328 }
329 return -ENOSPC;
330}
331
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800332static inline int bfs_namecmp(int len, const unsigned char *name,
333 const char *buffer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800335 if ((len < BFS_NAMELEN) && buffer[len])
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 return 0;
337 return !memcmp(name, buffer, len);
338}
339
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800340static struct buffer_head *bfs_find_entry(struct inode *dir,
341 const unsigned char *name, int namelen,
342 struct bfs_dirent **res_dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343{
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800344 unsigned long block = 0, offset = 0;
345 struct buffer_head *bh = NULL;
346 struct bfs_dirent *de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347
348 *res_dir = NULL;
349 if (namelen > BFS_NAMELEN)
350 return NULL;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800351
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 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;
Dmitri Vorobievf433dc52007-11-14 16:59:47 -0800362 if (le16_to_cpu(de->ino) &&
363 bfs_namecmp(namelen, name, de->name)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 *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}