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linux/arch/um/drivers/vde_user.c
Jeff Dike b53f35a809 uml: network driver MTU cleanups
A bunch of MTU-related cleanups in the network code.

First, there is the addition of the notion of a maximally-sized packet, which
is the MTU plus headers.  This is used to size the skb that will receive a
packet.  This allows ether_adjust_skb to go away, as it was used to resize the
skb after it was allocated.

Since the skb passed into the low-level read routine is no longer resized, and
possibly reallocated, there, they (and the write routines) don't need to get
an sk_buff **.  They just need the sk_buff * now.  The callers of
ether_adjust_skb still need to do the skb_put, so that's now inlined.

The MAX_PACKET definitions in most of the drivers are gone.

The set_mtu methods were all the same and did nothing, so they can be
removed.

The ethertap driver had a typo which doubled the size of the packet rather
than adding two bytes to it.  It also wasn't defining its setup_size, causing
a zero-byte kmalloc and crash when the invalid pointer returned from kmalloc
was dereferenced.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:08 -07:00

128 lines
2.4 KiB
C

/*
* Copyright (C) 2007 Luca Bigliardi (shammash@artha.org).
* Licensed under the GPL.
*/
#include <stddef.h>
#include <errno.h>
#include <libvdeplug.h>
#include "kern_constants.h"
#include "net_user.h"
#include "um_malloc.h"
#include "user.h"
#include "vde.h"
static int vde_user_init(void *data, void *dev)
{
struct vde_data *pri = data;
VDECONN *conn = NULL;
int err = -EINVAL;
pri->dev = dev;
conn = vde_open(pri->vde_switch, pri->descr, pri->args);
if (conn == NULL) {
err = -errno;
printk(UM_KERN_ERR "vde_user_init: vde_open failed, "
"errno = %d\n", errno);
return err;
}
printk(UM_KERN_INFO "vde backend - connection opened\n");
pri->conn = conn;
return 0;
}
static int vde_user_open(void *data)
{
struct vde_data *pri = data;
if (pri->conn != NULL)
return vde_datafd(pri->conn);
printk(UM_KERN_WARNING "vde_open - we have no VDECONN to open");
return -EINVAL;
}
static void vde_remove(void *data)
{
struct vde_data *pri = data;
if (pri->conn != NULL) {
printk(UM_KERN_INFO "vde backend - closing connection\n");
vde_close(pri->conn);
pri->conn = NULL;
kfree(pri->args);
pri->args = NULL;
return;
}
printk(UM_KERN_WARNING "vde_remove - we have no VDECONN to remove");
}
const struct net_user_info vde_user_info = {
.init = vde_user_init,
.open = vde_user_open,
.close = NULL,
.remove = vde_remove,
.add_address = NULL,
.delete_address = NULL,
.mtu = ETH_MAX_PACKET,
.max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};
void vde_init_libstuff(struct vde_data *vpri, struct vde_init *init)
{
struct vde_open_args *args;
vpri->args = kmalloc(sizeof(struct vde_open_args), UM_GFP_KERNEL);
if (vpri->args == NULL) {
printk(UM_KERN_ERR "vde_init_libstuff - vde_open_args"
"allocation failed");
return;
}
args = vpri->args;
args->port = init->port;
args->group = init->group;
args->mode = init->mode ? init->mode : 0700;
args->port ? printk(UM_KERN_INFO "port %d", args->port) :
printk(UM_KERN_INFO "undefined port");
}
int vde_user_read(void *conn, void *buf, int len)
{
VDECONN *vconn = conn;
int rv;
if (vconn == NULL)
return 0;
rv = vde_recv(vconn, buf, len, 0);
if (rv < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (rv == 0)
return -ENOTCONN;
return rv;
}
int vde_user_write(void *conn, void *buf, int len)
{
VDECONN *vconn = conn;
if (vconn == NULL)
return 0;
return vde_send(vconn, buf, len, 0);
}