Commit 7769f772 authored by Maksim Krasnyanskiy's avatar Maksim Krasnyanskiy Committed by Linus Torvalds

[PATCH] 2.5.x TUN/TAP driver readv/writev support

This adds proper support for readv/writev in the TUN/TAP driver.
parent 4293dac3
/*
* TUN - Universal TUN/TAP device driver.
* Copyright (C) 1999-2000 Maxim Krasnyansky <max_mk@yahoo.com>
* Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
*
* 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
......@@ -12,7 +12,7 @@
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* $Id: tun.c,v 1.12 2001/03/08 03:29:27 maxk Exp $
* $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
*/
/*
......@@ -20,7 +20,7 @@
* Modifications for 2.3.99-pre5 kernel.
*/
#define TUN_VER "1.4"
#define TUN_VER "1.5"
#include <linux/config.h>
#include <linux/module.h>
......@@ -181,50 +181,26 @@ static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
}
/* Get packet from user space buffer(already verified) */
static __inline__ ssize_t
tun_get_user(struct tun_struct *tun, const struct iovec *iov,
unsigned long count, size_t total)
static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
{
struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
const struct iovec *vector = &iov[0];
register const char *ptr = vector->iov_base;
register int len = vector->iov_len;
struct sk_buff *skb;
ssize_t sent = 0;
size_t len = count;
if (!(tun->flags & TUN_NO_PI)) {
if ((len -= sizeof(pi)) < 0)
return -EINVAL;
copy_from_user(&pi, ptr, sizeof(pi));
ptr += sizeof(pi);
if (len == 0) {
vector++;
count--;
ptr = vector->iov_base;
len = vector->iov_len;
}
memcpy_fromiovec((void *)&pi, iv, sizeof(pi));
}
if (!(skb = alloc_skb(total + 2, GFP_KERNEL))) {
if (!(skb = alloc_skb(len + 2, GFP_KERNEL))) {
tun->stats.rx_dropped++;
return -ENOMEM;
}
skb_reserve(skb, 2);
while (count > 0) {
copy_from_user(skb_put(skb, len), ptr, len);
sent += len;
vector++;
count--;
ptr = vector->iov_base;
len = vector->iov_len;
}
memcpy_fromiovec(skb_put(skb, len), iv, len);
skb->dev = &tun->dev;
switch (tun->flags & TUN_TYPE_MASK) {
......@@ -243,60 +219,48 @@ tun_get_user(struct tun_struct *tun, const struct iovec *iov,
netif_rx_ni(skb);
tun->stats.rx_packets++;
tun->stats.rx_bytes += sent;
tun->stats.rx_bytes += len;
return total;
return count;
}
/* Write */
static ssize_t tun_chr_write(struct file * file, const char * buf,
size_t count, loff_t *pos)
/* Writev */
static ssize_t tun_chr_writev(struct file * file, const struct iovec *iv,
unsigned long count, loff_t *pos)
{
struct tun_struct *tun = (struct tun_struct *)file->private_data;
struct iovec iov;
unsigned long i;
size_t len;
if (!tun)
return -EBADFD;
DBG(KERN_INFO "%s: tun_chr_write %d\n", tun->name, count);
if (verify_area(VERIFY_READ, buf, count))
for (i = 0, len = 0; i < count; i++) {
if (verify_area(VERIFY_READ, iv[i].iov_base, iv[i].iov_len))
return -EFAULT;
len += iv[i].iov_len;
}
iov.iov_base = (char *) buf;
iov.iov_len = count;
return tun_get_user(tun, &iov, 1, count);
return tun_get_user(tun, (struct iovec *) iv, len);
}
/* Writev */
static ssize_t tun_chr_writev(struct file * file, const struct iovec *iov,
unsigned long count, loff_t *pos)
/* Write */
static ssize_t tun_chr_write(struct file * file, const char * buf,
size_t count, loff_t *pos)
{
struct tun_struct *tun = (struct tun_struct *)file->private_data;
size_t total = 0;
unsigned long i;
if (!tun)
return -EBADFD;
for (i = 0; i < count; i++) {
if (verify_area(VERIFY_READ, iov[i].iov_base, iov[i].iov_len))
return -EFAULT;
total += iov[i].iov_len;
}
return tun_get_user(tun, iov, count, total);
struct iovec iv = { (void *) buf, count };
return tun_chr_writev(file, &iv, 1, pos);
}
/* Put packet to user space buffer(already verified) */
/* Put packet to the user space buffer (already verified) */
static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
struct sk_buff *skb,
char *buf, int count)
struct iovec *iv, int len)
{
struct tun_pi pi = { 0, skb->protocol };
int len = count, total = 0;
char *ptr = buf;
ssize_t total = 0;
if (!(tun->flags & TUN_NO_PI)) {
if ((len -= sizeof(pi)) < 0)
......@@ -307,14 +271,13 @@ static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
pi.flags |= TUN_PKT_STRIP;
}
copy_to_user(ptr, &pi, sizeof(pi));
memcpy_toiovec(iv, (void *) &pi, sizeof(pi));
total += sizeof(pi);
ptr += sizeof(pi);
}
len = MIN(skb->len, len);
copy_to_user(ptr, skb->data, len);
skb_copy_datagram_iovec(skb, 0, iv, len);
total += len;
tun->stats.tx_packets++;
......@@ -323,22 +286,29 @@ static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
return total;
}
/* Read */
static ssize_t tun_chr_read(struct file * file, char * buf,
size_t count, loff_t *pos)
/* Readv */
static ssize_t tun_chr_readv(struct file *file, const struct iovec *iv,
unsigned long count, loff_t *pos)
{
struct tun_struct *tun = (struct tun_struct *)file->private_data;
DECLARE_WAITQUEUE(wait, current);
struct sk_buff *skb;
ssize_t ret = 0;
ssize_t len, ret = 0;
unsigned long i;
if (!tun)
return -EBADFD;
DBG(KERN_INFO "%s: tun_chr_read\n", tun->name);
for (i = 0, len = 0; i < count; i++) {
if (verify_area(VERIFY_WRITE, iv[i].iov_base, iv[i].iov_len))
return -EFAULT;
len += iv[i].iov_len;
}
add_wait_queue(&tun->read_wait, &wait);
while (count) {
while (len) {
current->state = TASK_INTERRUPTIBLE;
/* Read frames from the queue */
......@@ -358,10 +328,7 @@ static ssize_t tun_chr_read(struct file * file, char * buf,
}
netif_start_queue(&tun->dev);
if (!verify_area(VERIFY_WRITE, buf, count))
ret = tun_put_user(tun, skb, buf, count);
else
ret = -EFAULT;
ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
kfree_skb(skb);
break;
......@@ -373,6 +340,14 @@ static ssize_t tun_chr_read(struct file * file, char * buf,
return ret;
}
/* Read */
static ssize_t tun_chr_read(struct file * file, char * buf,
size_t count, loff_t *pos)
{
struct iovec iv = { buf, count };
return tun_chr_readv(file, &iv, 1, pos);
}
static int tun_set_iff(struct file *file, struct ifreq *ifr)
{
struct tun_struct *tun;
......@@ -592,6 +567,7 @@ static struct file_operations tun_fops = {
owner: THIS_MODULE,
llseek: no_llseek,
read: tun_chr_read,
readv: tun_chr_readv,
write: tun_chr_write,
writev: tun_chr_writev,
poll: tun_chr_poll,
......@@ -611,7 +587,7 @@ static struct miscdevice tun_miscdev=
int __init tun_init(void)
{
printk(KERN_INFO "Universal TUN/TAP device driver %s "
"(C)1999-2001 Maxim Krasnyansky\n", TUN_VER);
"(C)1999-2002 Maxim Krasnyansky\n", TUN_VER);
if (misc_register(&tun_miscdev)) {
printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
......
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