aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSven Eckelmann <sven.eckelmann@gmx.de>2010-09-05 01:58:32 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2010-09-05 00:29:48 -0700
commitaedbffc7774574de74563f350b363cbfb52984fd (patch)
tree20ef515ff41eaad27d9271182d79a9c434db3483
parentb411d498eeed97ed14a42abeffac2012dd10d971 (diff)
downloadmrst-s0i3-test-aedbffc7774574de74563f350b363cbfb52984fd.tar.gz
mrst-s0i3-test-aedbffc7774574de74563f350b363cbfb52984fd.tar.xz
mrst-s0i3-test-aedbffc7774574de74563f350b363cbfb52984fd.zip
Staging: batman-adv: Create copy of skb with pre-allocated headroom
We can use skb_cow instead of a handwritten function to test and create a writable skb buffer. This also allows us to pre-allocate headroom to be able to send the data without re-allocating the buffer again to add the ethernet header. Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r--drivers/staging/batman-adv/routing.c77
1 files changed, 24 insertions, 53 deletions
diff --git a/drivers/staging/batman-adv/routing.c b/drivers/staging/batman-adv/routing.c
index d8e77ac21c2..7e993a25349 100644
--- a/drivers/staging/batman-adv/routing.c
+++ b/drivers/staging/batman-adv/routing.c
@@ -742,7 +742,6 @@ int recv_bat_packet(struct sk_buff *skb,
{
struct ethhdr *ethhdr;
unsigned long flags;
- struct sk_buff *skb_old;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < sizeof(struct batman_packet))
@@ -758,18 +757,11 @@ int recv_bat_packet(struct sk_buff *skb,
if (is_bcast(ethhdr->h_source))
return NET_RX_DROP;
- /* TODO: we use headlen instead of "length", because
- * only this data is paged in. */
-
/* create a copy of the skb, if needed, to modify it. */
- if (!skb_clone_writable(skb, skb_headlen(skb))) {
- skb_old = skb;
- skb = skb_copy(skb, GFP_ATOMIC);
- if (!skb)
- return NET_RX_DROP;
- ethhdr = (struct ethhdr *)skb_mac_header(skb);
- kfree_skb(skb_old);
- }
+ if (skb_cow(skb, 0) < 0)
+ return NET_RX_DROP;
+
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
spin_lock_irqsave(&orig_hash_lock, flags);
receive_aggr_bat_packet(ethhdr,
@@ -789,7 +781,6 @@ static int recv_my_icmp_packet(struct sk_buff *skb, size_t icmp_len)
struct orig_node *orig_node;
struct icmp_packet_rr *icmp_packet;
struct ethhdr *ethhdr;
- struct sk_buff *skb_old;
struct batman_if *batman_if;
int ret;
unsigned long flags;
@@ -824,16 +815,11 @@ static int recv_my_icmp_packet(struct sk_buff *skb, size_t icmp_len)
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
- skb_old = NULL;
- if (!skb_clone_writable(skb, icmp_len)) {
- skb_old = skb;
- skb = skb_copy(skb, GFP_ATOMIC);
- if (!skb)
- return NET_RX_DROP;
- icmp_packet = (struct icmp_packet_rr *)skb->data;
- ethhdr = (struct ethhdr *)skb_mac_header(skb);
- kfree_skb(skb_old);
- }
+ if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
+ return NET_RX_DROP;
+
+ icmp_packet = (struct icmp_packet_rr *)skb->data;
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
memcpy(icmp_packet->orig,
@@ -857,7 +843,6 @@ static int recv_icmp_ttl_exceeded(struct sk_buff *skb, size_t icmp_len)
struct orig_node *orig_node;
struct icmp_packet *icmp_packet;
struct ethhdr *ethhdr;
- struct sk_buff *skb_old;
struct batman_if *batman_if;
int ret;
unsigned long flags;
@@ -893,15 +878,11 @@ static int recv_icmp_ttl_exceeded(struct sk_buff *skb, size_t icmp_len)
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
- if (!skb_clone_writable(skb, icmp_len)) {
- skb_old = skb;
- skb = skb_copy(skb, GFP_ATOMIC);
- if (!skb)
- return NET_RX_DROP;
- icmp_packet = (struct icmp_packet *) skb->data;
- ethhdr = (struct ethhdr *)skb_mac_header(skb);
- kfree_skb(skb_old);
- }
+ if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
+ return NET_RX_DROP;
+
+ icmp_packet = (struct icmp_packet *) skb->data;
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
memcpy(icmp_packet->orig,
@@ -924,7 +905,6 @@ int recv_icmp_packet(struct sk_buff *skb)
struct icmp_packet_rr *icmp_packet;
struct ethhdr *ethhdr;
struct orig_node *orig_node;
- struct sk_buff *skb_old;
struct batman_if *batman_if;
int hdr_size = sizeof(struct icmp_packet);
int ret;
@@ -990,15 +970,11 @@ int recv_icmp_packet(struct sk_buff *skb)
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
- if (!skb_clone_writable(skb, hdr_size)) {
- skb_old = skb;
- skb = skb_copy(skb, GFP_ATOMIC);
- if (!skb)
- return NET_RX_DROP;
- icmp_packet = (struct icmp_packet_rr *)skb->data;
- ethhdr = (struct ethhdr *)skb_mac_header(skb);
- kfree_skb(skb_old);
- }
+ if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
+ return NET_RX_DROP;
+
+ icmp_packet = (struct icmp_packet_rr *)skb->data;
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* decrement ttl */
icmp_packet->ttl--;
@@ -1137,7 +1113,6 @@ static int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if,
struct orig_node *orig_node;
struct neigh_node *router;
struct batman_if *batman_if;
- struct sk_buff *skb_old;
uint8_t dstaddr[ETH_ALEN];
unsigned long flags;
struct unicast_packet *unicast_packet =
@@ -1173,15 +1148,11 @@ static int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if,
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
- if (!skb_clone_writable(skb, hdr_size)) {
- skb_old = skb;
- skb = skb_copy(skb, GFP_ATOMIC);
- if (!skb)
- return NET_RX_DROP;
- unicast_packet = (struct unicast_packet *) skb->data;
- ethhdr = (struct ethhdr *)skb_mac_header(skb);
- kfree_skb(skb_old);
- }
+ if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
+ return NET_RX_DROP;
+
+ unicast_packet = (struct unicast_packet *) skb->data;
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* decrement ttl */
unicast_packet->ttl--;