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>
printk("\n");
}
-static int daemon_read(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int daemon_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
- if (*skb == NULL)
- return -ENOMEM;
- return net_recvfrom(fd, skb_mac_header(*skb),
- (*skb)->dev->mtu + ETH_HEADER_OTHER);
+ return net_recvfrom(fd, skb_mac_header(skb),
+ skb->dev->mtu + ETH_HEADER_OTHER);
}
-static int daemon_write(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int daemon_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return daemon_user_write(fd, (*skb)->data, (*skb)->len,
+ return daemon_user_write(fd, skb->data, skb->len,
(struct daemon_data *) &lp->user);
}
#include "um_malloc.h"
#include "user.h"
-#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER)
-
enum request_type { REQ_NEW_CONTROL };
#define SWITCH_MAGIC 0xfeedface
return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr));
}
-static int daemon_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
const struct net_user_info daemon_user_info = {
.init = daemon_user_init,
.open = daemon_open,
.close = NULL,
.remove = daemon_remove,
- .set_mtu = daemon_set_mtu,
.add_address = NULL,
.delete_address = NULL,
- .max_packet = MAX_PACKET - ETH_HEADER_OTHER
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};
dpri->addr, dpri->port, dpri->ttl);
}
-static int mcast_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int mcast_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
- if (*skb == NULL)
- return -ENOMEM;
- return net_recvfrom(fd, skb_mac_header(*skb),
- (*skb)->dev->mtu + ETH_HEADER_OTHER);
+ return net_recvfrom(fd, skb_mac_header(skb),
+ skb->dev->mtu + ETH_HEADER_OTHER);
}
-static int mcast_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int mcast_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return mcast_user_write(fd, (*skb)->data, (*skb)->len,
+ return mcast_user_write(fd, skb->data, skb->len,
(struct mcast_data *) &lp->user);
}
#include "um_malloc.h"
#include "user.h"
-#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER)
-
static struct sockaddr_in *new_addr(char *addr, unsigned short port)
{
struct sockaddr_in *sin;
return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr));
}
-static int mcast_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
const struct net_user_info mcast_user_info = {
.init = mcast_user_init,
.open = mcast_open,
.close = mcast_close,
.remove = mcast_remove,
- .set_mtu = mcast_set_mtu,
.add_address = NULL,
.delete_address = NULL,
- .max_packet = MAX_PACKET - ETH_HEADER_OTHER
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};
struct sk_buff *skb;
/* If we can't allocate memory, try again next round. */
- skb = dev_alloc_skb(dev->mtu);
+ skb = dev_alloc_skb(lp->max_packet);
if (skb == NULL) {
lp->stats.rx_dropped++;
return 0;
}
skb->dev = dev;
- skb_put(skb, dev->mtu);
+ skb_put(skb, lp->max_packet);
skb_reset_mac_header(skb);
- pkt_len = (*lp->read)(lp->fd, &skb, lp);
+ pkt_len = (*lp->read)(lp->fd, skb, lp);
if (pkt_len > 0) {
skb_trim(skb, pkt_len);
spin_lock_irqsave(&lp->lock, flags);
- len = (*lp->write)(lp->fd, &skb, lp);
+ len = (*lp->write)(lp->fd, skb, lp);
if (len == skb->len) {
lp->stats.tx_packets++;
static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
{
- struct uml_net_private *lp = dev->priv;
- int err = 0;
-
- spin_lock_irq(&lp->lock);
-
- new_mtu = (*lp->set_mtu)(new_mtu, &lp->user);
- if (new_mtu < 0) {
- err = new_mtu;
- goto out;
- }
-
dev->mtu = new_mtu;
- out:
- spin_unlock_irq(&lp->lock);
- return err;
+ return 0;
}
static void uml_net_get_drvinfo(struct net_device *dev,
.dev = dev,
.fd = -1,
.mac = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
+ .max_packet = transport->user->max_packet,
.protocol = transport->kern->protocol,
.open = transport->user->open,
.close = transport->user->close,
.read = transport->kern->read,
.write = transport->kern->write,
.add_address = transport->user->add_address,
- .delete_address = transport->user->delete_address,
- .set_mtu = transport->user->set_mtu });
+ .delete_address = transport->user->delete_address });
init_timer(&lp->tl);
spin_lock_init(&lp->lock);
goto out_unregister;
set_ether_mac(dev, device->mac);
- dev->mtu = transport->user->max_packet;
+ dev->mtu = transport->user->mtu;
dev->open = uml_net_open;
dev->hard_start_xmit = uml_net_start_xmit;
dev->stop = uml_net_close;
__uml_exitcall(close_devices);
-struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra)
-{
- if ((skb != NULL) && (skb_tailroom(skb) < extra)) {
- struct sk_buff *skb2;
-
- skb2 = skb_copy_expand(skb, 0, extra, GFP_ATOMIC);
- dev_kfree_skb(skb);
- skb = skb2;
- }
- if (skb != NULL) skb_put(skb, extra);
- return skb;
-}
-
void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
void *),
void *arg)
printk("pcap backend, host interface %s\n", ppri->host_if);
}
-static int pcap_read(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int pcap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
- if (*skb == NULL)
- return -ENOMEM;
-
- return pcap_user_read(fd, skb_mac_header(*skb),
- (*skb)->dev->mtu + ETH_HEADER_OTHER,
+ return pcap_user_read(fd, skb_mac_header(skb),
+ skb->dev->mtu + ETH_HEADER_OTHER,
(struct pcap_data *) &lp->user);
}
-static int pcap_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int pcap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
return -EPERM;
}
#include "um_malloc.h"
#include "user.h"
-#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER)
-
#define PCAP_FD(p) (*(int *)(p))
static int pcap_user_init(void *data, void *dev)
pcap_t *p;
char errors[PCAP_ERRBUF_SIZE];
- p = pcap_open_live(pri->host_if, MAX_PACKET, pri->promisc, 0, errors);
+ p = pcap_open_live(pri->host_if, ETH_MAX_PACKET + ETH_HEADER_OTHER,
+ pri->promisc, 0, errors);
if (p == NULL) {
printk(UM_KERN_ERR "pcap_user_init : pcap_open_live failed - "
"'%s'\n", errors);
.open = pcap_open,
.close = NULL,
.remove = pcap_remove,
- .set_mtu = NULL,
.add_address = NULL,
.delete_address = NULL,
- .max_packet = MAX_PACKET - ETH_HEADER_OTHER
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};
return htons(ETH_P_IP);
}
-static int slip_read(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int slip_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return slip_user_read(fd, skb_mac_header(*skb), (*skb)->dev->mtu,
+ return slip_user_read(fd, skb_mac_header(skb), skb->dev->mtu,
(struct slip_data *) &lp->user);
}
-static int slip_write(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int slip_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return slip_user_write(fd, (*skb)->data, (*skb)->len,
+ return slip_user_write(fd, skb->data, skb->len,
(struct slip_data *) &lp->user);
}
return slip_proto_write(fd, buf, len, &pri->slip);
}
-static int slip_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
static void slip_add_addr(unsigned char *addr, unsigned char *netmask,
void *data)
{
.open = slip_open,
.close = slip_close,
.remove = NULL,
- .set_mtu = slip_set_mtu,
.add_address = slip_add_addr,
.delete_address = slip_del_addr,
- .max_packet = BUF_SIZE
+ .mtu = BUF_SIZE,
+ .max_packet = BUF_SIZE,
};
return htons(ETH_P_IP);
}
-static int slirp_read(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int slirp_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return slirp_user_read(fd, skb_mac_header(*skb), (*skb)->dev->mtu,
- (struct slirp_data *) &lp->user);
+ return slirp_user_read(fd, skb_mac_header(skb), skb->dev->mtu,
+ (struct slirp_data *) &lp->user);
}
-static int slirp_write(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int slirp_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return slirp_user_write(fd, (*skb)->data, (*skb)->len,
- (struct slirp_data *) &lp->user);
+ return slirp_user_write(fd, skb->data, skb->len,
+ (struct slirp_data *) &lp->user);
}
const struct net_kern_info slirp_kern_info = {
return slip_proto_write(fd, buf, len, &pri->slip);
}
-static int slirp_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
const struct net_user_info slirp_user_info = {
.init = slirp_user_init,
.open = slirp_open,
.close = slirp_close,
.remove = NULL,
- .set_mtu = slirp_set_mtu,
.add_address = NULL,
.delete_address = NULL,
- .max_packet = BUF_SIZE
+ .mtu = BUF_SIZE,
+ .max_packet = BUF_SIZE,
};
printk("\n");
}
-static int vde_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int vde_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
struct vde_data *pri = (struct vde_data *) &lp->user;
- if (pri->conn != NULL) {
- *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
- if (*skb == NULL)
- return -ENOMEM;
-
- return vde_user_read(pri->conn, skb_mac_header(*skb),
- (*skb)->dev->mtu + ETH_HEADER_OTHER);
- }
+ if (pri->conn != NULL)
+ return vde_user_read(pri->conn, skb_mac_header(skb),
+ skb->dev->mtu + ETH_HEADER_OTHER);
printk(KERN_ERR "vde_read - we have no VDECONN to read from");
return -EBADF;
}
-static int vde_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int vde_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
struct vde_data *pri = (struct vde_data *) &lp->user;
if (pri->conn != NULL)
- return vde_user_write((void *)pri->conn, (*skb)->data,
- (*skb)->len);
+ return vde_user_write((void *)pri->conn, skb->data,
+ skb->len);
printk(KERN_ERR "vde_write - we have no VDECONN to write to");
return -EBADF;
#include "user.h"
#include "vde.h"
-#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER)
-
static int vde_user_init(void *data, void *dev)
{
struct vde_data *pri = data;
printk(UM_KERN_WARNING "vde_remove - we have no VDECONN to remove");
}
-static int vde_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
const struct net_user_info vde_user_info = {
.init = vde_user_init,
.open = vde_user_open,
.close = NULL,
.remove = vde_remove,
- .set_mtu = vde_set_mtu,
.add_address = NULL,
.delete_address = NULL,
- .max_packet = MAX_PACKET - ETH_HEADER_OTHER
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};
void vde_init_libstuff(struct vde_data *vpri, struct vde_init *init)
/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2002 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
struct work_struct work;
int fd;
unsigned char mac[ETH_ALEN];
+ int max_packet;
unsigned short (*protocol)(struct sk_buff *);
int (*open)(void *);
void (*close)(int, void *);
void (*remove)(void *);
- int (*read)(int, struct sk_buff **skb, struct uml_net_private *);
- int (*write)(int, struct sk_buff **skb, struct uml_net_private *);
+ int (*read)(int, struct sk_buff *skb, struct uml_net_private *);
+ int (*write)(int, struct sk_buff *skb, struct uml_net_private *);
void (*add_address)(unsigned char *, unsigned char *, void *);
void (*delete_address)(unsigned char *, unsigned char *, void *);
- int (*set_mtu)(int mtu, void *);
char user[0];
};
struct net_kern_info {
void (*init)(struct net_device *, void *);
unsigned short (*protocol)(struct sk_buff *);
- int (*read)(int, struct sk_buff **skb, struct uml_net_private *);
- int (*write)(int, struct sk_buff **skb, struct uml_net_private *);
+ int (*read)(int, struct sk_buff *skb, struct uml_net_private *);
+ int (*write)(int, struct sk_buff *skb, struct uml_net_private *);
};
struct transport {
extern struct net_device *ether_init(int);
extern unsigned short ether_protocol(struct sk_buff *);
-extern struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra);
extern int tap_setup_common(char *str, char *type, char **dev_name,
char **mac_out, char **gate_addr);
extern void register_transport(struct transport *new);
/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
int (*open)(void *);
void (*close)(int, void *);
void (*remove)(void *);
- int (*set_mtu)(int mtu, void *);
void (*add_address)(unsigned char *, unsigned char *, void *);
void (*delete_address)(unsigned char *, unsigned char *, void *);
int max_packet;
+ int mtu;
};
extern void ether_user_init(void *data, void *dev);
printk("\n");
}
-static int etap_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int etap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
int len;
- *skb = ether_adjust_skb(*skb, ETH_HEADER_ETHERTAP);
- if (*skb == NULL)
- return -ENOMEM;
- len = net_recvfrom(fd, skb_mac_header(*skb),
- (*skb)->dev->mtu + 2 * ETH_HEADER_ETHERTAP);
+ len = net_recvfrom(fd, skb_mac_header(skb),
+ skb->dev->mtu + 2 + ETH_HEADER_ETHERTAP);
if (len <= 0)
- return len;
- skb_pull(*skb, 2);
+ return(len);
+
+ skb_pull(skb, 2);
len -= 2;
return len;
}
-static int etap_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+static int etap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- if (skb_headroom(*skb) < 2) {
- struct sk_buff *skb2;
-
- skb2 = skb_realloc_headroom(*skb, 2);
- dev_kfree_skb(*skb);
- if (skb2 == NULL)
- return -ENOMEM;
- *skb = skb2;
- }
- skb_push(*skb, 2);
- return net_send(fd, (*skb)->data, (*skb)->len);
+ skb_push(skb, 2);
+ return net_send(fd, skb->data, skb->len);
}
const struct net_kern_info ethertap_kern_info = {
.user = ðertap_user_info,
.kern = ðertap_kern_info,
.private_size = sizeof(struct ethertap_data),
+ .setup_size = sizeof(struct ethertap_init),
};
static int register_ethertap(void)
pri->control_fd = -1;
}
-static int etap_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
void *data)
{
.open = etap_open,
.close = etap_close,
.remove = NULL,
- .set_mtu = etap_set_mtu,
.add_address = etap_add_addr,
.delete_address = etap_del_addr,
- .max_packet = MAX_PACKET - ETH_HEADER_ETHERTAP
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_ETHERTAP,
};
printk("\n");
}
-static int tuntap_read(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int tuntap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
- if (*skb == NULL)
- return -ENOMEM;
- return net_read(fd, skb_mac_header(*skb),
- (*skb)->dev->mtu + ETH_HEADER_OTHER);
+ return net_read(fd, skb_mac_header(skb),
+ skb->dev->mtu + ETH_HEADER_OTHER);
}
-static int tuntap_write(int fd, struct sk_buff **skb,
- struct uml_net_private *lp)
+static int tuntap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
- return net_write(fd, (*skb)->data, (*skb)->len);
+ return net_write(fd, skb->data, skb->len);
}
const struct net_kern_info tuntap_kern_info = {
#include "tuntap.h"
#include "user.h"
-#define MAX_PACKET ETH_MAX_PACKET
-
static int tuntap_user_init(void *data, void *dev)
{
struct tuntap_data *pri = data;
pri->fd = -1;
}
-static int tuntap_set_mtu(int mtu, void *data)
-{
- return mtu;
-}
-
const struct net_user_info tuntap_user_info = {
.init = tuntap_user_init,
.open = tuntap_open,
.close = tuntap_close,
.remove = NULL,
- .set_mtu = tuntap_set_mtu,
.add_address = tuntap_add_addr,
.delete_address = tuntap_del_addr,
- .max_packet = MAX_PACKET
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
};