linux/arch/um/drivers/daemon_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

195 lines
4.3 KiB
C

/*
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
* James Leu (jleu@mindspring.net).
* Copyright (C) 2001 by various other people who didn't put their name here.
* Licensed under the GPL.
*/
#include <stdint.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/un.h>
#include "daemon.h"
#include "net_user.h"
#include "os.h"
#include "um_malloc.h"
#include "user.h"
enum request_type { REQ_NEW_CONTROL };
#define SWITCH_MAGIC 0xfeedface
struct request_v3 {
uint32_t magic;
uint32_t version;
enum request_type type;
struct sockaddr_un sock;
};
static struct sockaddr_un *new_addr(void *name, int len)
{
struct sockaddr_un *sun;
sun = kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
if (sun == NULL) {
printk(UM_KERN_ERR "new_addr: allocation of sockaddr_un "
"failed\n");
return NULL;
}
sun->sun_family = AF_UNIX;
memcpy(sun->sun_path, name, len);
return sun;
}
static int connect_to_switch(struct daemon_data *pri)
{
struct sockaddr_un *ctl_addr = pri->ctl_addr;
struct sockaddr_un *local_addr = pri->local_addr;
struct sockaddr_un *sun;
struct request_v3 req;
int fd, n, err;
pri->control = socket(AF_UNIX, SOCK_STREAM, 0);
if (pri->control < 0) {
err = -errno;
printk(UM_KERN_ERR "daemon_open : control socket failed, "
"errno = %d\n", -err);
return err;
}
if (connect(pri->control, (struct sockaddr *) ctl_addr,
sizeof(*ctl_addr)) < 0) {
err = -errno;
printk(UM_KERN_ERR "daemon_open : control connect failed, "
"errno = %d\n", -err);
goto out;
}
fd = socket(AF_UNIX, SOCK_DGRAM, 0);
if (fd < 0) {
err = -errno;
printk(UM_KERN_ERR "daemon_open : data socket failed, "
"errno = %d\n", -err);
goto out;
}
if (bind(fd, (struct sockaddr *) local_addr, sizeof(*local_addr)) < 0) {
err = -errno;
printk(UM_KERN_ERR "daemon_open : data bind failed, "
"errno = %d\n", -err);
goto out_close;
}
sun = kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
if (sun == NULL) {
printk(UM_KERN_ERR "new_addr: allocation of sockaddr_un "
"failed\n");
err = -ENOMEM;
goto out_close;
}
req.magic = SWITCH_MAGIC;
req.version = SWITCH_VERSION;
req.type = REQ_NEW_CONTROL;
req.sock = *local_addr;
n = write(pri->control, &req, sizeof(req));
if (n != sizeof(req)) {
printk(UM_KERN_ERR "daemon_open : control setup request "
"failed, err = %d\n", -errno);
err = -ENOTCONN;
goto out_free;
}
n = read(pri->control, sun, sizeof(*sun));
if (n != sizeof(*sun)) {
printk(UM_KERN_ERR "daemon_open : read of data socket failed, "
"err = %d\n", -errno);
err = -ENOTCONN;
goto out_free;
}
pri->data_addr = sun;
return fd;
out_free:
kfree(sun);
out_close:
close(fd);
out:
close(pri->control);
return err;
}
static int daemon_user_init(void *data, void *dev)
{
struct daemon_data *pri = data;
struct timeval tv;
struct {
char zero;
int pid;
int usecs;
} name;
if (!strcmp(pri->sock_type, "unix"))
pri->ctl_addr = new_addr(pri->ctl_sock,
strlen(pri->ctl_sock) + 1);
name.zero = 0;
name.pid = os_getpid();
gettimeofday(&tv, NULL);
name.usecs = tv.tv_usec;
pri->local_addr = new_addr(&name, sizeof(name));
pri->dev = dev;
pri->fd = connect_to_switch(pri);
if (pri->fd < 0) {
kfree(pri->local_addr);
pri->local_addr = NULL;
return pri->fd;
}
return 0;
}
static int daemon_open(void *data)
{
struct daemon_data *pri = data;
return pri->fd;
}
static void daemon_remove(void *data)
{
struct daemon_data *pri = data;
close(pri->fd);
pri->fd = -1;
close(pri->control);
pri->control = -1;
kfree(pri->data_addr);
pri->data_addr = NULL;
kfree(pri->ctl_addr);
pri->ctl_addr = NULL;
kfree(pri->local_addr);
pri->local_addr = NULL;
}
int daemon_user_write(int fd, void *buf, int len, struct daemon_data *pri)
{
struct sockaddr_un *data_addr = pri->data_addr;
return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr));
}
const struct net_user_info daemon_user_info = {
.init = daemon_user_init,
.open = daemon_open,
.close = NULL,
.remove = daemon_remove,
.add_address = NULL,
.delete_address = NULL,
.mtu = ETH_MAX_PACKET,
.max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};