diff options
author | Jeff Dike <jdike@addtoit.com> | 2007-10-16 01:27:31 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-16 09:43:08 -0700 |
commit | b53f35a8093e6aed7e8e880eaa0b89a3d2fdfb0a (patch) | |
tree | 50e19688753650e27b1f7fc1d48eb8683666e6b7 /arch/um/os-Linux/drivers | |
parent | cd1ae0e49bdd814cfaa2e5ab28cff21a30e20085 (diff) |
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>
Diffstat (limited to 'arch/um/os-Linux/drivers')
-rw-r--r-- | arch/um/os-Linux/drivers/ethertap_kern.c | 30 | ||||
-rw-r--r-- | arch/um/os-Linux/drivers/ethertap_user.c | 9 | ||||
-rw-r--r-- | arch/um/os-Linux/drivers/tuntap_kern.c | 15 | ||||
-rw-r--r-- | arch/um/os-Linux/drivers/tuntap_user.c | 11 |
4 files changed, 19 insertions, 46 deletions
diff --git a/arch/um/os-Linux/drivers/ethertap_kern.c b/arch/um/os-Linux/drivers/ethertap_kern.c index 542bcc58354..04f11b9f1ac 100644 --- a/arch/um/os-Linux/drivers/ethertap_kern.c +++ b/arch/um/os-Linux/drivers/ethertap_kern.c @@ -36,35 +36,24 @@ static void etap_init(struct net_device *dev, void *data) 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 = { @@ -99,6 +88,7 @@ static struct transport ethertap_transport = { .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) diff --git a/arch/um/os-Linux/drivers/ethertap_user.c b/arch/um/os-Linux/drivers/ethertap_user.c index 29404b955f1..4ff55360344 100644 --- a/arch/um/os-Linux/drivers/ethertap_user.c +++ b/arch/um/os-Linux/drivers/ethertap_user.c @@ -222,11 +222,6 @@ static void etap_close(int fd, void *data) 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) { @@ -254,8 +249,8 @@ const struct net_user_info ethertap_user_info = { .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, }; diff --git a/arch/um/os-Linux/drivers/tuntap_kern.c b/arch/um/os-Linux/drivers/tuntap_kern.c index 9ade1f892ac..9d384807b07 100644 --- a/arch/um/os-Linux/drivers/tuntap_kern.c +++ b/arch/um/os-Linux/drivers/tuntap_kern.c @@ -35,20 +35,15 @@ static void tuntap_init(struct net_device *dev, void *data) 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 = { diff --git a/arch/um/os-Linux/drivers/tuntap_user.c b/arch/um/os-Linux/drivers/tuntap_user.c index 10714a413cf..6c55d3c8ead 100644 --- a/arch/um/os-Linux/drivers/tuntap_user.c +++ b/arch/um/os-Linux/drivers/tuntap_user.c @@ -18,8 +18,6 @@ #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; @@ -206,18 +204,13 @@ static void tuntap_close(int fd, void *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, }; |