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>
diff --git a/arch/um/drivers/pcap_user.c b/arch/um/drivers/pcap_user.c
index cf996b8..e980935 100644
--- a/arch/um/drivers/pcap_user.c
+++ b/arch/um/drivers/pcap_user.c
@@ -13,8 +13,6 @@
#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)
@@ -23,7 +21,8 @@
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);
@@ -133,8 +132,8 @@
.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,
};