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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>
Al Viro914e2632006-10-18 13:55:46 -040029#include <linux/sched.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070030#include <linux/file.h>
31#include <linux/stat.h>
32#include <linux/string.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070033#include <linux/inet.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070034#include <linux/list.h>
Abhishek Kulkarni637d0202009-09-22 11:34:05 -050035#include <linux/pagemap.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070036#include <asm/uaccess.h>
37#include <linux/idr.h>
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050038#include <net/9p/9p.h>
39#include <net/9p/client.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070040
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070041#include "v9fs.h"
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070042#include "v9fs_vfs.h"
43#include "fid.h"
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -050044#include "cache.h"
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070045
Adrian Bunkd32b6872007-03-05 02:49:48 +010046static const struct file_operations v9fs_cached_file_operations;
47
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070048/**
49 * v9fs_file_open - open a file (or directory)
50 * @inode: inode to be opened
51 * @file: file being opened
52 *
53 */
54
55int v9fs_file_open(struct inode *inode, struct file *file)
56{
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080057 int err;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050058 struct v9fs_session_info *v9ses;
59 struct p9_fid *fid;
60 int omode;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070061
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050062 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p \n", inode, file);
63 v9ses = v9fs_inode2v9ses(inode);
Eric Van Hensbergen2e4bef42008-06-24 17:39:39 -050064 omode = v9fs_uflags2omode(file->f_flags, v9fs_extended(v9ses));
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050065 fid = file->private_data;
66 if (!fid) {
67 fid = v9fs_fid_clone(file->f_path.dentry);
68 if (IS_ERR(fid))
69 return PTR_ERR(fid);
70
71 err = p9_client_open(fid, omode);
Eric Van Hensbergen9523a842007-07-13 13:01:27 -050072 if (err < 0) {
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050073 p9_client_clunk(fid);
74 return err;
75 }
Eric Van Hensbergen9523a842007-07-13 13:01:27 -050076 if (omode & P9_OTRUNC) {
Abhishek Kulkarni7549ae32009-09-22 11:34:05 -050077 i_size_write(inode, 0);
Eric Van Hensbergen9523a842007-07-13 13:01:27 -050078 inode->i_blocks = 0;
79 }
Eric Van Hensbergen2e4bef42008-06-24 17:39:39 -050080 if ((file->f_flags & O_APPEND) && (!v9fs_extended(v9ses)))
81 generic_file_llseek(file, 0, SEEK_END);
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080082 }
83
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050084 file->private_data = fid;
85 if ((fid->qid.version) && (v9ses->cache)) {
86 P9_DPRINTK(P9_DEBUG_VFS, "cached");
Eric Van Hensbergene03abc02007-02-11 13:21:39 -060087 /* enable cached file options */
88 if(file->f_op == &v9fs_file_operations)
89 file->f_op = &v9fs_cached_file_operations;
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -050090
91#ifdef CONFIG_9P_FSCACHE
92 v9fs_cache_inode_set_cookie(inode, file);
93#endif
Eric Van Hensbergene03abc02007-02-11 13:21:39 -060094 }
95
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070096 return 0;
97}
98
99/**
100 * v9fs_file_lock - lock a file (or directory)
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600101 * @filp: file to be locked
102 * @cmd: lock command
103 * @fl: file lock structure
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700104 *
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600105 * Bugs: this looks like a local only lock, we should extend into 9P
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700106 * by using open exclusive
107 */
108
109static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
110{
111 int res = 0;
Josef "Jeff" Sipekd6f787b2006-12-08 02:36:45 -0800112 struct inode *inode = filp->f_path.dentry->d_inode;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700113
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500114 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700115
116 /* No mandatory locks */
Pavel Emelyanov66abe5f2007-10-01 14:41:13 -0700117 if (__mandatory_lock(inode))
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700118 return -ENOLCK;
119
120 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
OGAWA Hirofumi28fd1292006-01-08 01:02:14 -0800121 filemap_write_and_wait(inode->i_mapping);
Andrew Mortonfc0ecff2007-02-10 01:45:39 -0800122 invalidate_mapping_pages(&inode->i_data, 0, -1);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700123 }
124
125 return res;
126}
127
128/**
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500129 * v9fs_file_readn - read from a file
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600130 * @filp: file pointer to read
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700131 * @data: data buffer to read data into
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500132 * @udata: user data buffer to read data into
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700133 * @count: size of buffer
134 * @offset: offset at which to read data
135 *
136 */
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500137
138ssize_t
139v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
140 u64 offset)
141{
142 int n, total;
143 struct p9_fid *fid = filp->private_data;
144
Eric Van Hensbergen51a87c52008-10-16 08:30:07 -0500145 P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500146 (long long unsigned) offset, count);
147
148 n = 0;
149 total = 0;
150 do {
151 n = p9_client_read(fid, data, udata, offset, count);
152 if (n <= 0)
153 break;
154
155 if (data)
156 data += n;
157 if (udata)
158 udata += n;
159
160 offset += n;
161 count -= n;
162 total += n;
163 } while (count > 0 && n == (fid->clnt->msize - P9_IOHDRSZ));
164
165 if (n < 0)
166 total = n;
167
168 return total;
169}
170
171/**
172 * v9fs_file_read - read from a file
173 * @filp: file pointer to read
174 * @udata: user data buffer to read data into
175 * @count: size of buffer
176 * @offset: offset at which to read data
177 *
178 */
179
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700180static ssize_t
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500181v9fs_file_read(struct file *filp, char __user *udata, size_t count,
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700182 loff_t * offset)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700183{
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500184 int ret;
185 struct p9_fid *fid;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700186
Eric Van Hensbergenea2e7992008-10-22 18:48:45 -0500187 P9_DPRINTK(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500188 fid = filp->private_data;
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500189
190 if (count > (fid->clnt->msize - P9_IOHDRSZ))
191 ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
192 else
193 ret = p9_client_read(fid, NULL, udata, *offset, count);
194
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500195 if (ret > 0)
196 *offset += ret;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700197
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500198 return ret;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700199}
200
201/**
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700202 * v9fs_file_write - write to a file
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600203 * @filp: file pointer to write
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700204 * @data: data buffer to write data from
205 * @count: size of buffer
206 * @offset: offset at which to write data
207 *
208 */
209
210static ssize_t
211v9fs_file_write(struct file *filp, const char __user * data,
212 size_t count, loff_t * offset)
213{
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500214 int n, rsize, total = 0;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500215 struct p9_fid *fid;
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500216 struct p9_client *clnt;
Eric Van Hensbergen9523a842007-07-13 13:01:27 -0500217 struct inode *inode = filp->f_path.dentry->d_inode;
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500218 int origin = *offset;
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500219 unsigned long pg_start, pg_end;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700220
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500221 P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
222 (int)count, (int)*offset);
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700223
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500224 fid = filp->private_data;
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500225 clnt = fid->clnt;
226
227 rsize = fid->iounit;
228 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
229 rsize = clnt->msize - P9_IOHDRSZ;
230
231 do {
232 if (count < rsize)
233 rsize = count;
234
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500235 n = p9_client_write(fid, NULL, data+total, origin+total,
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500236 rsize);
237 if (n <= 0)
238 break;
239 count -= n;
240 total += n;
241 } while (count > 0);
242
243 if (total > 0) {
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500244 pg_start = origin >> PAGE_CACHE_SHIFT;
245 pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -0500246 if (inode->i_mapping && inode->i_mapping->nrpages)
247 invalidate_inode_pages2_range(inode->i_mapping,
248 pg_start, pg_end);
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500249 *offset += total;
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500250 i_size_write(inode, i_size_read(inode) + total);
Abhishek Kulkarni7549ae32009-09-22 11:34:05 -0500251 inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
Eric Van Hensbergen9523a842007-07-13 13:01:27 -0500252 }
253
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500254 if (n < 0)
255 return n;
256
257 return total;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700258}
259
Adrian Bunkd32b6872007-03-05 02:49:48 +0100260static const struct file_operations v9fs_cached_file_operations = {
Eric Van Hensbergene03abc02007-02-11 13:21:39 -0600261 .llseek = generic_file_llseek,
262 .read = do_sync_read,
263 .aio_read = generic_file_aio_read,
264 .write = v9fs_file_write,
265 .open = v9fs_file_open,
266 .release = v9fs_dir_release,
267 .lock = v9fs_file_lock,
Eric Van Hensbergen14b88692008-02-06 19:25:05 -0600268 .mmap = generic_file_readonly_mmap,
Eric Van Hensbergene03abc02007-02-11 13:21:39 -0600269};
270
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800271const struct file_operations v9fs_file_operations = {
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700272 .llseek = generic_file_llseek,
273 .read = v9fs_file_read,
274 .write = v9fs_file_write,
275 .open = v9fs_file_open,
276 .release = v9fs_dir_release,
277 .lock = v9fs_file_lock,
Eric Van Hensbergen14b88692008-02-06 19:25:05 -0600278 .mmap = generic_file_readonly_mmap,
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700279};