2 * linux/fs/9p/vfs_dir.c
4 * This file contains vfs directory ops for the 9P2000 protocol.
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to:
20 * Free Software Foundation
21 * 51 Franklin Street, Fifth Floor
22 * Boston, MA 02111-1301 USA
26 #include <linux/module.h>
27 #include <linux/errno.h>
29 #include <linux/file.h>
30 #include <linux/stat.h>
31 #include <linux/string.h>
32 #include <linux/sched.h>
33 #include <linux/inet.h>
34 #include <linux/idr.h>
35 #include <linux/slab.h>
36 #include <net/9p/9p.h>
37 #include <net/9p/client.h>
44 * struct p9_rdir - readdir accounting
45 * @mutex: mutex protecting readdir
46 * @head: start offset of current dirread buffer
47 * @tail: end offset of current dirread buffer
48 * @buf: dirread buffer
50 * private structure for keeping track of readdir
62 * dt_type - return file type
63 * @mistat: mistat structure
67 static inline int dt_type(struct p9_wstat
*mistat
)
69 unsigned long perm
= mistat
->mode
;
74 if (perm
& P9_DMSYMLINK
)
80 static void p9stat_init(struct p9_wstat
*stbuf
)
86 stbuf
->extension
= NULL
;
90 * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
91 * @filp: opened file structure
92 * @buflen: Length in bytes of buffer to allocate
96 static int v9fs_alloc_rdir_buf(struct file
*filp
, int buflen
)
102 fid
= filp
->private_data
;
104 rdir
= kmalloc(sizeof(struct p9_rdir
) + buflen
, GFP_KERNEL
);
110 spin_lock(&filp
->f_dentry
->d_lock
);
112 rdir
->buf
= (uint8_t *)rdir
+ sizeof(struct p9_rdir
);
113 mutex_init(&rdir
->mutex
);
114 rdir
->head
= rdir
->tail
= 0;
115 fid
->rdir
= (void *) rdir
;
118 spin_unlock(&filp
->f_dentry
->d_lock
);
126 * v9fs_dir_readdir - read a directory
127 * @filp: opened file structure
128 * @dirent: directory structure ???
129 * @filldir: function to populate directory structure ???
133 static int v9fs_dir_readdir(struct file
*filp
, void *dirent
, filldir_t filldir
)
141 struct p9_rdir
*rdir
;
143 P9_DPRINTK(P9_DEBUG_VFS
, "name %s\n", filp
->f_path
.dentry
->d_name
.name
);
144 fid
= filp
->private_data
;
146 buflen
= fid
->clnt
->msize
- P9_IOHDRSZ
;
148 err
= v9fs_alloc_rdir_buf(filp
, buflen
);
151 rdir
= (struct p9_rdir
*) fid
->rdir
;
153 err
= mutex_lock_interruptible(&rdir
->mutex
);
157 if (rdir
->tail
== rdir
->head
) {
158 err
= v9fs_file_readn(filp
, rdir
->buf
, NULL
,
159 buflen
, filp
->f_pos
);
161 goto unlock_and_exit
;
166 while (rdir
->head
< rdir
->tail
) {
168 err
= p9stat_read(rdir
->buf
+ rdir
->head
,
169 rdir
->tail
- rdir
->head
, &st
,
170 fid
->clnt
->proto_version
);
172 P9_DPRINTK(P9_DEBUG_VFS
, "returned %d\n", err
);
175 goto unlock_and_exit
;
179 over
= filldir(dirent
, st
.name
, strlen(st
.name
),
180 filp
->f_pos
, v9fs_qid2ino(&st
.qid
), dt_type(&st
));
186 goto unlock_and_exit
;
188 rdir
->head
+= reclen
;
189 filp
->f_pos
+= reclen
;
194 mutex_unlock(&rdir
->mutex
);
200 * v9fs_dir_readdir_dotl - read a directory
201 * @filp: opened file structure
202 * @dirent: buffer to fill dirent structures
203 * @filldir: function to populate dirent structures
206 static int v9fs_dir_readdir_dotl(struct file
*filp
, void *dirent
,
213 struct p9_rdir
*rdir
;
214 struct p9_dirent curdirent
;
217 P9_DPRINTK(P9_DEBUG_VFS
, "name %s\n", filp
->f_path
.dentry
->d_name
.name
);
218 fid
= filp
->private_data
;
220 buflen
= fid
->clnt
->msize
- P9_READDIRHDRSZ
;
222 err
= v9fs_alloc_rdir_buf(filp
, buflen
);
225 rdir
= (struct p9_rdir
*) fid
->rdir
;
227 err
= mutex_lock_interruptible(&rdir
->mutex
);
232 if (rdir
->tail
== rdir
->head
) {
233 err
= p9_client_readdir(fid
, rdir
->buf
, buflen
,
236 goto unlock_and_exit
;
242 while (rdir
->head
< rdir
->tail
) {
244 err
= p9dirent_read(rdir
->buf
+ rdir
->head
,
245 rdir
->tail
- rdir
->head
,
247 fid
->clnt
->proto_version
);
249 P9_DPRINTK(P9_DEBUG_VFS
, "returned %d\n", err
);
251 goto unlock_and_exit
;
254 /* d_off in dirent structure tracks the offset into
255 * the next dirent in the dir. However, filldir()
256 * expects offset into the current dirent. Hence
257 * while calling filldir send the offset from the
258 * previous dirent structure.
260 over
= filldir(dirent
, curdirent
.d_name
,
261 strlen(curdirent
.d_name
),
262 oldoffset
, v9fs_qid2ino(&curdirent
.qid
),
264 oldoffset
= curdirent
.d_off
;
268 goto unlock_and_exit
;
271 filp
->f_pos
= curdirent
.d_off
;
277 mutex_unlock(&rdir
->mutex
);
284 * v9fs_dir_release - close a directory
285 * @inode: inode of the directory
286 * @filp: file pointer to a directory
290 int v9fs_dir_release(struct inode
*inode
, struct file
*filp
)
294 fid
= filp
->private_data
;
295 P9_DPRINTK(P9_DEBUG_VFS
,
296 "v9fs_dir_release: inode: %p filp: %p fid: %d\n",
297 inode
, filp
, fid
? fid
->fid
: -1);
299 p9_client_clunk(fid
);
303 const struct file_operations v9fs_dir_operations
= {
304 .read
= generic_read_dir
,
305 .llseek
= generic_file_llseek
,
306 .readdir
= v9fs_dir_readdir
,
307 .open
= v9fs_file_open
,
308 .release
= v9fs_dir_release
,
311 const struct file_operations v9fs_dir_operations_dotl
= {
312 .read
= generic_read_dir
,
313 .llseek
= generic_file_llseek
,
314 .readdir
= v9fs_dir_readdir_dotl
,
315 .open
= v9fs_file_open
,
316 .release
= v9fs_dir_release
,
317 .fsync
= v9fs_file_fsync_dotl
,