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Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -07001/*
2 * linux/fs/9p/vfs_file.c
3 *
4 * This file contians vfs file ops for 9P2000.
5 *
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8 *
9 * This program is free software; you can redistribute it and/or modify
Eric Van Hensbergen42e8c502006-03-25 03:07:28 -080010 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070012 *
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.
17 *
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
23 *
24 */
25
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/smp_lock.h>
33#include <linux/inet.h>
Latchesar Ionkov531b1092006-01-08 01:05:00 -080034#include <linux/version.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070035#include <linux/list.h>
36#include <asm/uaccess.h>
37#include <linux/idr.h>
38
39#include "debug.h"
40#include "v9fs.h"
41#include "9p.h"
42#include "v9fs_vfs.h"
43#include "fid.h"
44
45/**
46 * v9fs_file_open - open a file (or directory)
47 * @inode: inode to be opened
48 * @file: file being opened
49 *
50 */
51
52int v9fs_file_open(struct inode *inode, struct file *file)
53{
54 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080055 struct v9fs_fid *vfid;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070056 struct v9fs_fcall *fcall = NULL;
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080057 int omode;
58 int fid = V9FS_NOFID;
59 int err;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070060
Latchesar Ionkov0b8dd172005-09-27 21:45:24 -070061 dprintk(DEBUG_VFS, "inode: %p file: %p \n", inode, file);
62
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080063 vfid = v9fs_fid_lookup(file->f_dentry);
64 if (!vfid) {
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070065 dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n");
Latchesar Ionkov0b8dd172005-09-27 21:45:24 -070066 return -EBADF;
67 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070068
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080069 fid = v9fs_get_idpool(&v9ses->fidpool);
70 if (fid < 0) {
Latchesar Ionkov16cce6d2006-03-25 03:07:26 -080071 eprintk(KERN_WARNING, "newfid fails!\n");
72 return -ENOSPC;
73 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070074
Latchesar Ionkov41e5a6a2006-05-15 09:44:21 -070075 err = v9fs_t_walk(v9ses, vfid->fid, fid, NULL, &fcall);
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080076 if (err < 0) {
Latchesar Ionkov16cce6d2006-03-25 03:07:26 -080077 dprintk(DEBUG_ERROR, "rewalk didn't work\n");
Latchesar Ionkov41e5a6a2006-05-15 09:44:21 -070078 if (fcall && fcall->id == RWALK)
79 goto clunk_fid;
80 else {
81 v9fs_put_idpool(fid, &v9ses->fidpool);
82 goto free_fcall;
83 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070084 }
Latchesar Ionkov41e5a6a2006-05-15 09:44:21 -070085 kfree(fcall);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070086
Latchesar Ionkov16cce6d2006-03-25 03:07:26 -080087 /* TODO: do special things for O_EXCL, O_NOFOLLOW, O_SYNC */
88 /* translate open mode appropriately */
89 omode = v9fs_uflags2omode(file->f_flags);
90 err = v9fs_t_open(v9ses, fid, omode, &fcall);
91 if (err < 0) {
92 PRINT_FCALL_ERROR("open failed", fcall);
93 goto clunk_fid;
94 }
95
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080096 vfid = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
97 if (vfid == NULL) {
98 dprintk(DEBUG_ERROR, "out of memory\n");
Latchesar Ionkov16cce6d2006-03-25 03:07:26 -080099 err = -ENOMEM;
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -0800100 goto clunk_fid;
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -0800101 }
102
103 file->private_data = vfid;
104 vfid->fid = fid;
105 vfid->fidopen = 1;
106 vfid->fidclunked = 0;
107 vfid->iounit = fcall->params.ropen.iounit;
108 vfid->rdir_pos = 0;
109 vfid->rdir_fcall = NULL;
110 vfid->filp = file;
111 kfree(fcall);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700112
113 return 0;
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -0800114
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -0800115clunk_fid:
116 v9fs_t_clunk(v9ses, fid);
117
Latchesar Ionkov41e5a6a2006-05-15 09:44:21 -0700118free_fcall:
Latchesar Ionkov16cce6d2006-03-25 03:07:26 -0800119 kfree(fcall);
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -0800120
121 return err;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700122}
123
124/**
125 * v9fs_file_lock - lock a file (or directory)
126 * @inode: inode to be opened
127 * @file: file being opened
128 *
129 * XXX - this looks like a local only lock, we should extend into 9P
130 * by using open exclusive
131 */
132
133static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
134{
135 int res = 0;
136 struct inode *inode = filp->f_dentry->d_inode;
137
138 dprintk(DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
139
140 /* No mandatory locks */
141 if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
142 return -ENOLCK;
143
144 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
OGAWA Hirofumi28fd1292006-01-08 01:02:14 -0800145 filemap_write_and_wait(inode->i_mapping);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700146 invalidate_inode_pages(&inode->i_data);
147 }
148
149 return res;
150}
151
152/**
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700153 * v9fs_file_read - read from a file
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700154 * @filep: file pointer to read
155 * @data: data buffer to read data into
156 * @count: size of buffer
157 * @offset: offset at which to read data
158 *
159 */
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700160static ssize_t
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700161v9fs_file_read(struct file *filp, char __user * data, size_t count,
162 loff_t * offset)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700163{
164 struct inode *inode = filp->f_dentry->d_inode;
165 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
166 struct v9fs_fid *v9f = filp->private_data;
167 struct v9fs_fcall *fcall = NULL;
168 int fid = v9f->fid;
169 int rsize = 0;
170 int result = 0;
171 int total = 0;
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700172 int n;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700173
174 dprintk(DEBUG_VFS, "\n");
175
176 rsize = v9ses->maxdata - V9FS_IOHDRSZ;
177 if (v9f->iounit != 0 && rsize > v9f->iounit)
178 rsize = v9f->iounit;
179
180 do {
181 if (count < rsize)
182 rsize = count;
183
184 result = v9fs_t_read(v9ses, fid, *offset, rsize, &fcall);
185
186 if (result < 0) {
187 printk(KERN_ERR "9P2000: v9fs_t_read returned %d\n",
188 result);
189
190 kfree(fcall);
191 return total;
192 } else
193 *offset += result;
194
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700195 n = copy_to_user(data, fcall->params.rread.data, result);
196 if (n) {
197 dprintk(DEBUG_ERROR, "Problem copying to user %d\n", n);
198 kfree(fcall);
199 return -EFAULT;
200 }
201
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700202 count -= result;
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700203 data += result;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700204 total += result;
205
206 kfree(fcall);
207
208 if (result < rsize)
209 break;
210 } while (count);
211
212 return total;
213}
214
215/**
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700216 * v9fs_file_write - write to a file
217 * @filep: file pointer to write
218 * @data: data buffer to write data from
219 * @count: size of buffer
220 * @offset: offset at which to write data
221 *
222 */
223
224static ssize_t
225v9fs_file_write(struct file *filp, const char __user * data,
226 size_t count, loff_t * offset)
227{
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700228 struct inode *inode = filp->f_dentry->d_inode;
229 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
230 struct v9fs_fid *v9fid = filp->private_data;
231 struct v9fs_fcall *fcall;
232 int fid = v9fid->fid;
233 int result = -EIO;
234 int rsize = 0;
235 int total = 0;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700236
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700237 dprintk(DEBUG_VFS, "data %p count %d offset %x\n", data, (int)count,
238 (int)*offset);
239 rsize = v9ses->maxdata - V9FS_IOHDRSZ;
240 if (v9fid->iounit != 0 && rsize > v9fid->iounit)
241 rsize = v9fid->iounit;
242
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700243 do {
244 if (count < rsize)
245 rsize = count;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700246
Latchesar Ionkov531b1092006-01-08 01:05:00 -0800247 result = v9fs_t_write(v9ses, fid, *offset, rsize, data, &fcall);
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700248 if (result < 0) {
Latchesar Ionkov531b1092006-01-08 01:05:00 -0800249 PRINT_FCALL_ERROR("error while writing", fcall);
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700250 kfree(fcall);
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700251 return result;
252 } else
253 *offset += result;
254
255 kfree(fcall);
256 fcall = NULL;
257
258 if (result != rsize) {
259 eprintk(KERN_ERR,
260 "short write: v9fs_t_write returned %d\n",
261 result);
262 break;
263 }
264
265 count -= result;
266 data += result;
267 total += result;
268 } while (count);
269
Eric Van Hensbergen147b31c2006-01-18 17:43:02 -0800270 invalidate_inode_pages2(inode->i_mapping);
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700271 return total;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700272}
273
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800274const struct file_operations v9fs_file_operations = {
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700275 .llseek = generic_file_llseek,
276 .read = v9fs_file_read,
277 .write = v9fs_file_write,
278 .open = v9fs_file_open,
279 .release = v9fs_dir_release,
280 .lock = v9fs_file_lock,
Eric Van Hensbergen147b31c2006-01-18 17:43:02 -0800281 .mmap = generic_file_mmap,
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700282};