linux/fs/9p/trans_sock.c
Latchesar Ionkov 531b1094b7 [PATCH] v9fs: zero copy implementation
Performance enhancement reducing the number of copies in the data and
stat paths.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:06 -08:00

335 lines
6.9 KiB
C

/*
* linux/fs/9p/trans_socket.c
*
* Socket Transport Layer
*
* Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net>
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
* Copyright (C) 1995, 1996 by Olaf Kirch <okir@monad.swb.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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/config.h>
#include <linux/in.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/ipv6.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/un.h>
#include <asm/uaccess.h>
#include <linux/inet.h>
#include <linux/idr.h>
#include <linux/file.h>
#include "debug.h"
#include "v9fs.h"
#include "transport.h"
#define V9FS_PORT 564
struct v9fs_trans_sock {
struct socket *s;
struct file *filp;
};
/**
* v9fs_sock_recv - receive from a socket
* @v9ses: session information
* @v: buffer to receive data into
* @len: size of receive buffer
*
*/
static int v9fs_sock_recv(struct v9fs_transport *trans, void *v, int len)
{
int ret;
struct v9fs_trans_sock *ts;
if (!trans || trans->status == Disconnected) {
dprintk(DEBUG_ERROR, "disconnected ...\n");
return -EREMOTEIO;
}
ts = trans->priv;
if (!(ts->filp->f_flags & O_NONBLOCK))
dprintk(DEBUG_ERROR, "blocking read ...\n");
ret = kernel_read(ts->filp, ts->filp->f_pos, v, len);
if (ret <= 0) {
if (ret != -ERESTARTSYS && ret != -EAGAIN)
trans->status = Disconnected;
}
return ret;
}
/**
* v9fs_sock_send - send to a socket
* @v9ses: session information
* @v: buffer to send data from
* @len: size of send buffer
*
*/
static int v9fs_sock_send(struct v9fs_transport *trans, void *v, int len)
{
int ret;
mm_segment_t oldfs;
struct v9fs_trans_sock *ts;
if (!trans || trans->status == Disconnected) {
dprintk(DEBUG_ERROR, "disconnected ...\n");
return -EREMOTEIO;
}
ts = trans->priv;
if (!ts) {
dprintk(DEBUG_ERROR, "no transport ...\n");
return -EREMOTEIO;
}
if (!(ts->filp->f_flags & O_NONBLOCK))
dprintk(DEBUG_ERROR, "blocking write ...\n");
oldfs = get_fs();
set_fs(get_ds());
ret = vfs_write(ts->filp, (void __user *)v, len, &ts->filp->f_pos);
set_fs(oldfs);
if (ret < 0) {
if (ret != -ERESTARTSYS)
trans->status = Disconnected;
}
return ret;
}
static unsigned int v9fs_sock_poll(struct v9fs_transport *trans,
struct poll_table_struct *pt) {
int ret;
struct v9fs_trans_sock *ts;
mm_segment_t oldfs;
if (!trans) {
dprintk(DEBUG_ERROR, "no transport\n");
return -EIO;
}
ts = trans->priv;
if (trans->status != Connected || !ts) {
dprintk(DEBUG_ERROR, "transport disconnected: %d\n", trans->status);
return -EIO;
}
oldfs = get_fs();
set_fs(get_ds());
if (!ts->filp->f_op || !ts->filp->f_op->poll) {
dprintk(DEBUG_ERROR, "no poll operation\n");
ret = -EIO;
goto end;
}
ret = ts->filp->f_op->poll(ts->filp, pt);
end:
set_fs(oldfs);
return ret;
}
/**
* v9fs_tcp_init - initialize TCP socket
* @v9ses: session information
* @addr: address of server to mount
* @data: mount options
*
*/
static int
v9fs_tcp_init(struct v9fs_session_info *v9ses, const char *addr, char *data)
{
struct socket *csocket = NULL;
struct sockaddr_in sin_server;
int rc = 0;
struct v9fs_trans_sock *ts = NULL;
struct v9fs_transport *trans = v9ses->transport;
int fd;
trans->status = Disconnected;
ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
if (!ts)
return -ENOMEM;
trans->priv = ts;
ts->s = NULL;
ts->filp = NULL;
if (!addr)
return -EINVAL;
dprintk(DEBUG_TRANS, "Connecting to %s\n", addr);
sin_server.sin_family = AF_INET;
sin_server.sin_addr.s_addr = in_aton(addr);
sin_server.sin_port = htons(v9ses->port);
sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket);
rc = csocket->ops->connect(csocket,
(struct sockaddr *)&sin_server,
sizeof(struct sockaddr_in), 0);
if (rc < 0) {
eprintk(KERN_ERR,
"v9fs_trans_tcp: problem connecting socket to %s\n",
addr);
return rc;
}
csocket->sk->sk_allocation = GFP_NOIO;
fd = sock_map_fd(csocket);
if (fd < 0) {
sock_release(csocket);
kfree(ts);
trans->priv = NULL;
return fd;
}
ts->s = csocket;
ts->filp = fget(fd);
ts->filp->f_flags |= O_NONBLOCK;
trans->status = Connected;
return 0;
}
/**
* v9fs_unix_init - initialize UNIX domain socket
* @v9ses: session information
* @dev_name: path to named pipe
* @data: mount options
*
*/
static int
v9fs_unix_init(struct v9fs_session_info *v9ses, const char *dev_name,
char *data)
{
int rc, fd;
struct socket *csocket;
struct sockaddr_un sun_server;
struct v9fs_transport *trans;
struct v9fs_trans_sock *ts;
rc = 0;
csocket = NULL;
trans = v9ses->transport;
trans->status = Disconnected;
if (strlen(dev_name) > UNIX_PATH_MAX) {
eprintk(KERN_ERR, "v9fs_trans_unix: address too long: %s\n",
dev_name);
return -ENOMEM;
}
ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
if (!ts)
return -ENOMEM;
trans->priv = ts;
ts->s = NULL;
ts->filp = NULL;
sun_server.sun_family = PF_UNIX;
strcpy(sun_server.sun_path, dev_name);
sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket);
rc = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server,
sizeof(struct sockaddr_un) - 1, 0); /* -1 *is* important */
if (rc < 0) {
eprintk(KERN_ERR,
"v9fs_trans_unix: problem connecting socket: %s: %d\n",
dev_name, rc);
return rc;
}
csocket->sk->sk_allocation = GFP_NOIO;
fd = sock_map_fd(csocket);
if (fd < 0) {
sock_release(csocket);
kfree(ts);
trans->priv = NULL;
return fd;
}
ts->s = csocket;
ts->filp = fget(fd);
ts->filp->f_flags |= O_NONBLOCK;
trans->status = Connected;
return 0;
}
/**
* v9fs_sock_close - shutdown socket
* @trans: private socket structure
*
*/
static void v9fs_sock_close(struct v9fs_transport *trans)
{
struct v9fs_trans_sock *ts;
if (!trans)
return;
ts = trans->priv;
if ((ts) && (ts->filp)) {
fput(ts->filp);
ts->filp = NULL;
ts->s = NULL;
trans->status = Disconnected;
}
kfree(ts);
trans->priv = NULL;
}
struct v9fs_transport v9fs_trans_tcp = {
.init = v9fs_tcp_init,
.write = v9fs_sock_send,
.read = v9fs_sock_recv,
.close = v9fs_sock_close,
.poll = v9fs_sock_poll,
};
struct v9fs_transport v9fs_trans_unix = {
.init = v9fs_unix_init,
.write = v9fs_sock_send,
.read = v9fs_sock_recv,
.close = v9fs_sock_close,
.poll = v9fs_sock_poll,
};