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
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)
79 static void p9stat_init(struct p9_wstat *stbuf)
85 stbuf->extension = NULL;
89 * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
90 * @filp: opened file structure
91 * @buflen: Length in bytes of buffer to allocate
95 static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
97 struct p9_fid *fid = filp->private_data;
99 fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
104 * v9fs_dir_readdir - iterate through a directory
105 * @file: opened file structure
106 * @ctx: actor we feed the entries to
110 static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
118 struct p9_rdir *rdir;
120 p9_debug(P9_DEBUG_VFS, "name %s\n", file->f_path.dentry->d_name.name);
121 fid = file->private_data;
123 buflen = fid->clnt->msize - P9_IOHDRSZ;
125 rdir = v9fs_alloc_rdir_buf(file, buflen);
130 if (rdir->tail == rdir->head) {
131 err = v9fs_file_readn(file, rdir->buf, NULL,
139 while (rdir->head < rdir->tail) {
141 err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
142 rdir->tail - rdir->head, &st);
144 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
150 over = !dir_emit(ctx, st.name, strlen(st.name),
151 v9fs_qid2ino(&st.qid), dt_type(&st));
156 rdir->head += reclen;
163 * v9fs_dir_readdir_dotl - iterate through a directory
164 * @file: opened file structure
165 * @ctx: actor we feed the entries to
168 static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
173 struct p9_rdir *rdir;
174 struct p9_dirent curdirent;
176 p9_debug(P9_DEBUG_VFS, "name %s\n", file->f_path.dentry->d_name.name);
177 fid = file->private_data;
179 buflen = fid->clnt->msize - P9_READDIRHDRSZ;
181 rdir = v9fs_alloc_rdir_buf(file, buflen);
186 if (rdir->tail == rdir->head) {
187 err = p9_client_readdir(fid, rdir->buf, buflen,
196 while (rdir->head < rdir->tail) {
198 err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
199 rdir->tail - rdir->head,
202 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
206 if (!dir_emit(ctx, curdirent.d_name,
207 strlen(curdirent.d_name),
208 v9fs_qid2ino(&curdirent.qid),
212 ctx->pos = curdirent.d_off;
220 * v9fs_dir_release - close a directory
221 * @inode: inode of the directory
222 * @filp: file pointer to a directory
226 int v9fs_dir_release(struct inode *inode, struct file *filp)
230 fid = filp->private_data;
231 p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
232 inode, filp, fid ? fid->fid : -1);
234 p9_client_clunk(fid);
238 const struct file_operations v9fs_dir_operations = {
239 .read = generic_read_dir,
240 .llseek = generic_file_llseek,
241 .iterate = v9fs_dir_readdir,
242 .open = v9fs_file_open,
243 .release = v9fs_dir_release,
246 const struct file_operations v9fs_dir_operations_dotl = {
247 .read = generic_read_dir,
248 .llseek = generic_file_llseek,
249 .iterate = v9fs_dir_readdir_dotl,
250 .open = v9fs_file_open,
251 .release = v9fs_dir_release,
252 .fsync = v9fs_file_fsync_dotl,