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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;
Venkateswararao Jujjuri (JV)b04faaf2010-09-22 16:30:52 -070047static const struct file_operations v9fs_cached_file_operations_dotl;
Adrian Bunkd32b6872007-03-05 02:49:48 +010048
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070049/**
50 * v9fs_file_open - open a file (or directory)
51 * @inode: inode to be opened
52 * @file: file being opened
53 *
54 */
55
56int v9fs_file_open(struct inode *inode, struct file *file)
57{
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080058 int err;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050059 struct v9fs_session_info *v9ses;
60 struct p9_fid *fid;
61 int omode;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070062
M. Mohan Kumaref565472010-06-22 19:47:50 +053063 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050064 v9ses = v9fs_inode2v9ses(inode);
M. Mohan Kumaref565472010-06-22 19:47:50 +053065 if (v9fs_proto_dotl(v9ses))
66 omode = file->f_flags;
67 else
68 omode = v9fs_uflags2omode(file->f_flags,
69 v9fs_proto_dotu(v9ses));
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050070 fid = file->private_data;
71 if (!fid) {
72 fid = v9fs_fid_clone(file->f_path.dentry);
73 if (IS_ERR(fid))
74 return PTR_ERR(fid);
75
76 err = p9_client_open(fid, omode);
Eric Van Hensbergen9523a842007-07-13 13:01:27 -050077 if (err < 0) {
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050078 p9_client_clunk(fid);
79 return err;
80 }
M. Mohan Kumaref565472010-06-22 19:47:50 +053081 if (file->f_flags & O_TRUNC) {
Abhishek Kulkarni7549ae32009-09-22 11:34:05 -050082 i_size_write(inode, 0);
Eric Van Hensbergen9523a842007-07-13 13:01:27 -050083 inode->i_blocks = 0;
84 }
M. Mohan Kumaref565472010-06-22 19:47:50 +053085 if ((file->f_flags & O_APPEND) &&
86 (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
Eric Van Hensbergen2e4bef42008-06-24 17:39:39 -050087 generic_file_llseek(file, 0, SEEK_END);
Latchesar Ionkov6a3124a2006-03-02 02:54:30 -080088 }
89
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050090 file->private_data = fid;
91 if ((fid->qid.version) && (v9ses->cache)) {
92 P9_DPRINTK(P9_DEBUG_VFS, "cached");
Eric Van Hensbergene03abc02007-02-11 13:21:39 -060093 /* enable cached file options */
94 if(file->f_op == &v9fs_file_operations)
95 file->f_op = &v9fs_cached_file_operations;
Venkateswararao Jujjuri (JV)b04faaf2010-09-22 16:30:52 -070096 else if (file->f_op == &v9fs_file_operations_dotl)
97 file->f_op = &v9fs_cached_file_operations_dotl;
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -050098
99#ifdef CONFIG_9P_FSCACHE
100 v9fs_cache_inode_set_cookie(inode, file);
101#endif
Eric Van Hensbergene03abc02007-02-11 13:21:39 -0600102 }
103
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700104 return 0;
105}
106
107/**
108 * v9fs_file_lock - lock a file (or directory)
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600109 * @filp: file to be locked
110 * @cmd: lock command
111 * @fl: file lock structure
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700112 *
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600113 * Bugs: this looks like a local only lock, we should extend into 9P
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700114 * by using open exclusive
115 */
116
117static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
118{
119 int res = 0;
Josef "Jeff" Sipekd6f787b2006-12-08 02:36:45 -0800120 struct inode *inode = filp->f_path.dentry->d_inode;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700121
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500122 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700123
124 /* No mandatory locks */
Sachin Prabhuf78233d2010-03-13 09:03:55 -0600125 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700126 return -ENOLCK;
127
128 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
OGAWA Hirofumi28fd1292006-01-08 01:02:14 -0800129 filemap_write_and_wait(inode->i_mapping);
Andrew Mortonfc0ecff2007-02-10 01:45:39 -0800130 invalidate_mapping_pages(&inode->i_data, 0, -1);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700131 }
132
133 return res;
134}
135
136/**
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500137 * v9fs_file_readn - read from a file
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600138 * @filp: file pointer to read
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700139 * @data: data buffer to read data into
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500140 * @udata: user data buffer to read data into
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700141 * @count: size of buffer
142 * @offset: offset at which to read data
143 *
144 */
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500145
146ssize_t
147v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
148 u64 offset)
149{
M. Mohan Kumar97e84422010-06-04 11:59:07 +0000150 int n, total, size;
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500151 struct p9_fid *fid = filp->private_data;
152
Eric Van Hensbergen51a87c52008-10-16 08:30:07 -0500153 P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500154 (long long unsigned) offset, count);
155
156 n = 0;
157 total = 0;
M. Mohan Kumar97e84422010-06-04 11:59:07 +0000158 size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500159 do {
160 n = p9_client_read(fid, data, udata, offset, count);
161 if (n <= 0)
162 break;
163
164 if (data)
165 data += n;
166 if (udata)
167 udata += n;
168
169 offset += n;
170 count -= n;
171 total += n;
M. Mohan Kumar97e84422010-06-04 11:59:07 +0000172 } while (count > 0 && n == size);
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500173
174 if (n < 0)
175 total = n;
176
177 return total;
178}
179
180/**
181 * v9fs_file_read - read from a file
182 * @filp: file pointer to read
183 * @udata: user data buffer to read data into
184 * @count: size of buffer
185 * @offset: offset at which to read data
186 *
187 */
188
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700189static ssize_t
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500190v9fs_file_read(struct file *filp, char __user *udata, size_t count,
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700191 loff_t * offset)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700192{
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500193 int ret;
194 struct p9_fid *fid;
M. Mohan Kumar97e84422010-06-04 11:59:07 +0000195 size_t size;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700196
Eric Van Hensbergenea2e7992008-10-22 18:48:45 -0500197 P9_DPRINTK(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500198 fid = filp->private_data;
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500199
M. Mohan Kumar97e84422010-06-04 11:59:07 +0000200 size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
201 if (count > size)
Eric Van Hensbergenfbedadc2008-10-13 20:36:16 -0500202 ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
203 else
204 ret = p9_client_read(fid, NULL, udata, *offset, count);
205
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500206 if (ret > 0)
207 *offset += ret;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700208
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500209 return ret;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700210}
211
212/**
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700213 * v9fs_file_write - write to a file
Eric Van Hensbergenee443992008-03-05 07:08:09 -0600214 * @filp: file pointer to write
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700215 * @data: data buffer to write data from
216 * @count: size of buffer
217 * @offset: offset at which to write data
218 *
219 */
220
221static ssize_t
222v9fs_file_write(struct file *filp, const char __user * data,
223 size_t count, loff_t * offset)
224{
Harsh Prateek Bora3834b122010-08-03 11:55:40 +0000225 ssize_t retval;
226 size_t total = 0;
jvrao8d40fa22010-08-30 13:23:20 -0500227 int n;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500228 struct p9_fid *fid;
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500229 struct p9_client *clnt;
Eric Van Hensbergen9523a842007-07-13 13:01:27 -0500230 struct inode *inode = filp->f_path.dentry->d_inode;
jvraofc0f2962010-03-08 22:07:02 +0000231 loff_t origin = *offset;
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500232 unsigned long pg_start, pg_end;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700233
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500234 P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
235 (int)count, (int)*offset);
Latchesar Ionkov19cba8a2005-10-11 08:29:03 -0700236
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500237 fid = filp->private_data;
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500238 clnt = fid->clnt;
239
Harsh Prateek Bora3834b122010-08-03 11:55:40 +0000240 retval = generic_write_checks(filp, &origin, &count, 0);
241 if (retval)
242 goto out;
243
244 retval = -EINVAL;
245 if ((ssize_t) count < 0)
246 goto out;
247 retval = 0;
248 if (!count)
249 goto out;
250
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500251 do {
jvrao8d40fa22010-08-30 13:23:20 -0500252 n = p9_client_write(fid, NULL, data+total, origin+total, count);
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500253 if (n <= 0)
254 break;
255 count -= n;
256 total += n;
257 } while (count > 0);
258
259 if (total > 0) {
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500260 pg_start = origin >> PAGE_CACHE_SHIFT;
261 pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -0500262 if (inode->i_mapping && inode->i_mapping->nrpages)
263 invalidate_inode_pages2_range(inode->i_mapping,
264 pg_start, pg_end);
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500265 *offset += total;
Abhishek Kulkarni637d0202009-09-22 11:34:05 -0500266 i_size_write(inode, i_size_read(inode) + total);
Abhishek Kulkarni7549ae32009-09-22 11:34:05 -0500267 inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
Eric Van Hensbergen9523a842007-07-13 13:01:27 -0500268 }
269
Eric Van Hensbergendfb0ec22008-10-13 20:36:16 -0500270 if (n < 0)
Harsh Prateek Bora3834b122010-08-03 11:55:40 +0000271 retval = n;
272 else
273 retval = total;
274out:
275 return retval;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700276}
277
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200278static int v9fs_file_fsync(struct file *filp, int datasync)
M. Mohan Kumar7a4439c2010-02-08 15:36:48 -0600279{
280 struct p9_fid *fid;
281 struct p9_wstat wstat;
282 int retval;
283
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200284 P9_DPRINTK(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
M. Mohan Kumar7a4439c2010-02-08 15:36:48 -0600285
286 fid = filp->private_data;
287 v9fs_blank_wstat(&wstat);
288
289 retval = p9_client_wstat(fid, &wstat);
290 return retval;
291}
292
Adrian Bunkd32b6872007-03-05 02:49:48 +0100293static const struct file_operations v9fs_cached_file_operations = {
Eric Van Hensbergene03abc02007-02-11 13:21:39 -0600294 .llseek = generic_file_llseek,
295 .read = do_sync_read,
296 .aio_read = generic_file_aio_read,
297 .write = v9fs_file_write,
298 .open = v9fs_file_open,
299 .release = v9fs_dir_release,
300 .lock = v9fs_file_lock,
Eric Van Hensbergen14b88692008-02-06 19:25:05 -0600301 .mmap = generic_file_readonly_mmap,
M. Mohan Kumar7a4439c2010-02-08 15:36:48 -0600302 .fsync = v9fs_file_fsync,
Eric Van Hensbergene03abc02007-02-11 13:21:39 -0600303};
304
Venkateswararao Jujjuri (JV)b04faaf2010-09-22 16:30:52 -0700305static const struct file_operations v9fs_cached_file_operations_dotl = {
306 .llseek = generic_file_llseek,
307 .read = do_sync_read,
308 .aio_read = generic_file_aio_read,
309 .write = v9fs_file_write,
310 .open = v9fs_file_open,
311 .release = v9fs_dir_release,
312 .lock = v9fs_file_lock,
313 .mmap = generic_file_readonly_mmap,
314 .fsync = v9fs_file_fsync,
315};
316
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800317const struct file_operations v9fs_file_operations = {
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700318 .llseek = generic_file_llseek,
319 .read = v9fs_file_read,
320 .write = v9fs_file_write,
321 .open = v9fs_file_open,
322 .release = v9fs_dir_release,
323 .lock = v9fs_file_lock,
Eric Van Hensbergen14b88692008-02-06 19:25:05 -0600324 .mmap = generic_file_readonly_mmap,
M. Mohan Kumar7a4439c2010-02-08 15:36:48 -0600325 .fsync = v9fs_file_fsync,
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700326};
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000327
328const struct file_operations v9fs_file_operations_dotl = {
329 .llseek = generic_file_llseek,
330 .read = v9fs_file_read,
331 .write = v9fs_file_write,
332 .open = v9fs_file_open,
333 .release = v9fs_dir_release,
334 .lock = v9fs_file_lock,
335 .mmap = generic_file_readonly_mmap,
336 .fsync = v9fs_file_fsync,
337};