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/include/net_kern.h b/arch/um/include/net_kern.h
index 9237056..d843c79 100644
--- a/arch/um/include/net_kern.h
+++ b/arch/um/include/net_kern.h
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2002 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
@@ -30,24 +30,24 @@
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 {
@@ -62,7 +62,6 @@
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);