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/*
* linux/fs/9p/vfs_addr.c
*
* This file contians vfs address (mmap) ops for 9P2000.
*
* Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/inet.h>
#include <linux/pagemap.h>
#include <linux/idr.h>
#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "v9fs_vfs.h"
#include "fid.h"
/**
* v9fs_vfs_readpage - read an entire page in from 9P
*
* @file: file being read
* @page: structure to page
*
*/
static int v9fs_vfs_readpage(struct file *filp, struct page *page)
{
char *buffer = NULL;
int retval = -EIO;
loff_t offset = page_offset(page);
int count = PAGE_CACHE_SIZE;
struct inode *inode = filp->f_path.dentry->d_inode;
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
int rsize = v9ses->maxdata - V9FS_IOHDRSZ;
struct v9fs_fid *v9f = filp->private_data;
struct v9fs_fcall *fcall = NULL;
int fid = v9f->fid;
int total = 0;
int result = 0;
dprintk(DEBUG_VFS, "\n");
buffer = kmap(page);
do {
if (count < rsize)
rsize = count;
result = v9fs_t_read(v9ses, fid, offset, rsize, &fcall);
if (result < 0) {
printk(KERN_ERR "v9fs_t_read returned %d\n",
result);
kfree(fcall);
goto UnmapAndUnlock;
} else
offset += result;
memcpy(buffer, fcall->params.rread.data, result);
count -= result;
buffer += result;
total += result;
kfree(fcall);
if (result < rsize)
break;
} while (count);
memset(buffer, 0, count);
flush_dcache_page(page);
SetPageUptodate(page);
retval = 0;
UnmapAndUnlock:
kunmap(page);
unlock_page(page);
return retval;
}
const struct address_space_operations v9fs_addr_operations = {
.readpage = v9fs_vfs_readpage,
};
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