Blackfin/ipipe: fix deferred pipeline sync for the root stage
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / 9p / vfs_dir.c
blob9c2bdda5cd9de6556e6907711a38953041aa1ef5
1 /*
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>
28 #include <linux/fs.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>
39 #include "v9fs.h"
40 #include "v9fs_vfs.h"
41 #include "fid.h"
43 /**
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
51 * allocated on demand
54 struct p9_rdir {
55 struct mutex mutex;
56 int head;
57 int tail;
58 uint8_t *buf;
61 /**
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;
70 int rettype = DT_REG;
72 if (perm & P9_DMDIR)
73 rettype = DT_DIR;
74 if (perm & P9_DMSYMLINK)
75 rettype = DT_LNK;
77 return rettype;
80 static void p9stat_init(struct p9_wstat *stbuf)
82 stbuf->name = NULL;
83 stbuf->uid = NULL;
84 stbuf->gid = NULL;
85 stbuf->muid = NULL;
86 stbuf->extension = NULL;
89 /**
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)
98 struct p9_rdir *rdir;
99 struct p9_fid *fid;
100 int err = 0;
102 fid = filp->private_data;
103 if (!fid->rdir) {
104 rdir = kmalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
106 if (rdir == NULL) {
107 err = -ENOMEM;
108 goto exit;
110 spin_lock(&filp->f_dentry->d_lock);
111 if (!fid->rdir) {
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;
116 rdir = NULL;
118 spin_unlock(&filp->f_dentry->d_lock);
119 kfree(rdir);
121 exit:
122 return err;
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)
135 int over;
136 struct p9_wstat st;
137 int err = 0;
138 struct p9_fid *fid;
139 int buflen;
140 int reclen = 0;
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);
149 if (err)
150 goto exit;
151 rdir = (struct p9_rdir *) fid->rdir;
153 err = mutex_lock_interruptible(&rdir->mutex);
154 if (err)
155 return err;
156 while (err == 0) {
157 if (rdir->tail == rdir->head) {
158 err = v9fs_file_readn(filp, rdir->buf, NULL,
159 buflen, filp->f_pos);
160 if (err <= 0)
161 goto unlock_and_exit;
163 rdir->head = 0;
164 rdir->tail = err;
166 while (rdir->head < rdir->tail) {
167 p9stat_init(&st);
168 err = p9stat_read(rdir->buf + rdir->head,
169 rdir->tail - rdir->head, &st,
170 fid->clnt->proto_version);
171 if (err) {
172 P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
173 err = -EIO;
174 p9stat_free(&st);
175 goto unlock_and_exit;
177 reclen = st.size+2;
179 over = filldir(dirent, st.name, strlen(st.name),
180 filp->f_pos, v9fs_qid2ino(&st.qid), dt_type(&st));
182 p9stat_free(&st);
184 if (over) {
185 err = 0;
186 goto unlock_and_exit;
188 rdir->head += reclen;
189 filp->f_pos += reclen;
193 unlock_and_exit:
194 mutex_unlock(&rdir->mutex);
195 exit:
196 return err;
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,
207 filldir_t filldir)
209 int over;
210 int err = 0;
211 struct p9_fid *fid;
212 int buflen;
213 struct p9_rdir *rdir;
214 struct p9_dirent curdirent;
215 u64 oldoffset = 0;
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);
223 if (err)
224 goto exit;
225 rdir = (struct p9_rdir *) fid->rdir;
227 err = mutex_lock_interruptible(&rdir->mutex);
228 if (err)
229 return err;
231 while (err == 0) {
232 if (rdir->tail == rdir->head) {
233 err = p9_client_readdir(fid, rdir->buf, buflen,
234 filp->f_pos);
235 if (err <= 0)
236 goto unlock_and_exit;
238 rdir->head = 0;
239 rdir->tail = err;
242 while (rdir->head < rdir->tail) {
244 err = p9dirent_read(rdir->buf + rdir->head,
245 rdir->tail - rdir->head,
246 &curdirent,
247 fid->clnt->proto_version);
248 if (err < 0) {
249 P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
250 err = -EIO;
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),
263 curdirent.d_type);
264 oldoffset = curdirent.d_off;
266 if (over) {
267 err = 0;
268 goto unlock_and_exit;
271 filp->f_pos = curdirent.d_off;
272 rdir->head += err;
276 unlock_and_exit:
277 mutex_unlock(&rdir->mutex);
278 exit:
279 return err;
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)
292 struct p9_fid *fid;
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);
298 if (fid)
299 p9_client_clunk(fid);
300 return 0;
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,