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 <net/9p/9p.h>
36 #include <net/9p/client.h>
43 * struct p9_rdir - readdir accounting
44 * @mutex: mutex protecting readdir
45 * @head: start offset of current dirread buffer
46 * @tail: end offset of current dirread buffer
47 * @buf: dirread buffer
49 * private structure for keeping track of readdir
61 * dt_type - return file type
62 * @mistat: mistat structure
66 static inline int dt_type(struct p9_wstat *mistat)
68 unsigned long perm = mistat->mode;
73 if (perm & P9_DMSYMLINK)
80 * v9fs_dir_readdir - read a directory
81 * @filp: opened file structure
82 * @dirent: directory structure ???
83 * @filldir: function to populate directory structure ???
87 static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
97 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name);
98 fid = filp->private_data;
100 buflen = fid->clnt->msize - P9_IOHDRSZ;
102 /* allocate rdir on demand */
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);
121 rdir = (struct p9_rdir *) fid->rdir;
123 err = mutex_lock_interruptible(&rdir->mutex);
125 if (rdir->tail == rdir->head) {
126 err = v9fs_file_readn(filp, rdir->buf, NULL,
127 buflen, filp->f_pos);
129 goto unlock_and_exit;
135 while (rdir->head < rdir->tail) {
136 err = p9stat_read(rdir->buf + rdir->head,
137 buflen - rdir->head, &st,
140 P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
143 goto unlock_and_exit;
147 over = filldir(dirent, st.name, strlen(st.name),
148 filp->f_pos, v9fs_qid2ino(&st.qid), dt_type(&st));
154 goto unlock_and_exit;
156 rdir->head += reclen;
157 filp->f_pos += reclen;
162 mutex_unlock(&rdir->mutex);
169 * v9fs_dir_release - close a directory
170 * @inode: inode of the directory
171 * @filp: file pointer to a directory
175 int v9fs_dir_release(struct inode *inode, struct file *filp)
179 fid = filp->private_data;
180 P9_DPRINTK(P9_DEBUG_VFS,
181 "inode: %p filp: %p fid: %d\n", inode, filp, fid->fid);
182 filemap_write_and_wait(inode->i_mapping);
183 p9_client_clunk(fid);
187 const struct file_operations v9fs_dir_operations = {
188 .read = generic_read_dir,
189 .llseek = generic_file_llseek,
190 .readdir = v9fs_dir_readdir,
191 .open = v9fs_file_open,
192 .release = v9fs_dir_release,