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-rw-r--r--include/linux/netdevice.h8
-rw-r--r--net/core/dev.c127
-rw-r--r--net/sched/sch_generic.c19
3 files changed, 143 insertions, 11 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index fa5671307b90..b4eae18390cc 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -405,6 +405,9 @@ struct net_device
struct list_head qdisc_list;
unsigned long tx_queue_len; /* Max frames per queue allowed */
+ /* Partially transmitted GSO packet. */
+ struct sk_buff *gso_skb;
+
/* ingress path synchronizer */
spinlock_t ingress_lock;
struct Qdisc *qdisc_ingress;
@@ -539,6 +542,7 @@ struct packet_type {
struct net_device *,
struct packet_type *,
struct net_device *);
+ struct sk_buff *(*gso_segment)(struct sk_buff *skb, int sg);
void *af_packet_priv;
struct list_head list;
};
@@ -689,7 +693,8 @@ extern int dev_change_name(struct net_device *, char *);
extern int dev_set_mtu(struct net_device *, int);
extern int dev_set_mac_address(struct net_device *,
struct sockaddr *);
-extern void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev);
+extern int dev_hard_start_xmit(struct sk_buff *skb,
+ struct net_device *dev);
extern void dev_init(void);
@@ -963,6 +968,7 @@ extern int netdev_max_backlog;
extern int weight_p;
extern int netdev_set_master(struct net_device *dev, struct net_device *master);
extern int skb_checksum_help(struct sk_buff *skb, int inward);
+extern struct sk_buff *skb_gso_segment(struct sk_buff *skb, int sg);
#ifdef CONFIG_BUG
extern void netdev_rx_csum_fault(struct net_device *dev);
#else
diff --git a/net/core/dev.c b/net/core/dev.c
index 29e3888102bc..d293e0f90a0c 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -116,6 +116,7 @@
#include <asm/current.h>
#include <linux/audit.h>
#include <linux/dmaengine.h>
+#include <linux/err.h>
/*
* The list of packet types we will receive (as opposed to discard)
@@ -1048,7 +1049,7 @@ static inline void net_timestamp(struct sk_buff *skb)
* taps currently in use.
*/
-void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
+static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
{
struct packet_type *ptype;
@@ -1186,6 +1187,40 @@ out:
return ret;
}
+/**
+ * skb_gso_segment - Perform segmentation on skb.
+ * @skb: buffer to segment
+ * @sg: whether scatter-gather is supported on the target.
+ *
+ * This function segments the given skb and returns a list of segments.
+ */
+struct sk_buff *skb_gso_segment(struct sk_buff *skb, int sg)
+{
+ struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
+ struct packet_type *ptype;
+ int type = skb->protocol;
+
+ BUG_ON(skb_shinfo(skb)->frag_list);
+ BUG_ON(skb->ip_summed != CHECKSUM_HW);
+
+ skb->mac.raw = skb->data;
+ skb->mac_len = skb->nh.raw - skb->data;
+ __skb_pull(skb, skb->mac_len);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type) & 15], list) {
+ if (ptype->type == type && !ptype->dev && ptype->gso_segment) {
+ segs = ptype->gso_segment(skb, sg);
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return segs;
+}
+
+EXPORT_SYMBOL(skb_gso_segment);
+
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
@@ -1222,6 +1257,86 @@ static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
#define illegal_highdma(dev, skb) (0)
#endif
+struct dev_gso_cb {
+ void (*destructor)(struct sk_buff *skb);
+};
+
+#define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
+
+static void dev_gso_skb_destructor(struct sk_buff *skb)
+{
+ struct dev_gso_cb *cb;
+
+ do {
+ struct sk_buff *nskb = skb->next;
+
+ skb->next = nskb->next;
+ nskb->next = NULL;
+ kfree_skb(nskb);
+ } while (skb->next);
+
+ cb = DEV_GSO_CB(skb);
+ if (cb->destructor)
+ cb->destructor(skb);
+}
+
+/**
+ * dev_gso_segment - Perform emulated hardware segmentation on skb.
+ * @skb: buffer to segment
+ *
+ * This function segments the given skb and stores the list of segments
+ * in skb->next.
+ */
+static int dev_gso_segment(struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+ struct sk_buff *segs;
+
+ segs = skb_gso_segment(skb, dev->features & NETIF_F_SG &&
+ !illegal_highdma(dev, skb));
+ if (unlikely(IS_ERR(segs)))
+ return PTR_ERR(segs);
+
+ skb->next = segs;
+ DEV_GSO_CB(skb)->destructor = skb->destructor;
+ skb->destructor = dev_gso_skb_destructor;
+
+ return 0;
+}
+
+int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ if (likely(!skb->next)) {
+ if (netdev_nit)
+ dev_queue_xmit_nit(skb, dev);
+
+ if (!netif_needs_gso(dev, skb))
+ return dev->hard_start_xmit(skb, dev);
+
+ if (unlikely(dev_gso_segment(skb)))
+ goto out_kfree_skb;
+ }
+
+ do {
+ struct sk_buff *nskb = skb->next;
+ int rc;
+
+ skb->next = nskb->next;
+ nskb->next = NULL;
+ rc = dev->hard_start_xmit(nskb, dev);
+ if (unlikely(rc)) {
+ skb->next = nskb;
+ return rc;
+ }
+ } while (skb->next);
+
+ skb->destructor = DEV_GSO_CB(skb)->destructor;
+
+out_kfree_skb:
+ kfree_skb(skb);
+ return 0;
+}
+
#define HARD_TX_LOCK(dev, cpu) { \
if ((dev->features & NETIF_F_LLTX) == 0) { \
netif_tx_lock(dev); \
@@ -1266,6 +1381,10 @@ int dev_queue_xmit(struct sk_buff *skb)
struct Qdisc *q;
int rc = -ENOMEM;
+ /* GSO will handle the following emulations directly. */
+ if (netif_needs_gso(dev, skb))
+ goto gso;
+
if (skb_shinfo(skb)->frag_list &&
!(dev->features & NETIF_F_FRAGLIST) &&
__skb_linearize(skb))
@@ -1290,6 +1409,7 @@ int dev_queue_xmit(struct sk_buff *skb)
if (skb_checksum_help(skb, 0))
goto out_kfree_skb;
+gso:
spin_lock_prefetch(&dev->queue_lock);
/* Disable soft irqs for various locks below. Also
@@ -1346,11 +1466,8 @@ int dev_queue_xmit(struct sk_buff *skb)
HARD_TX_LOCK(dev, cpu);
if (!netif_queue_stopped(dev)) {
- if (netdev_nit)
- dev_queue_xmit_nit(skb, dev);
-
rc = 0;
- if (!dev->hard_start_xmit(skb, dev)) {
+ if (!dev_hard_start_xmit(skb, dev)) {
HARD_TX_UNLOCK(dev);
goto out;
}
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 7aad0121232c..74d4a1dceeec 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -96,8 +96,11 @@ static inline int qdisc_restart(struct net_device *dev)
struct sk_buff *skb;
/* Dequeue packet */
- if ((skb = q->dequeue(q)) != NULL) {
+ if (((skb = dev->gso_skb)) || ((skb = q->dequeue(q)))) {
unsigned nolock = (dev->features & NETIF_F_LLTX);
+
+ dev->gso_skb = NULL;
+
/*
* When the driver has LLTX set it does its own locking
* in start_xmit. No need to add additional overhead by
@@ -134,10 +137,8 @@ static inline int qdisc_restart(struct net_device *dev)
if (!netif_queue_stopped(dev)) {
int ret;
- if (netdev_nit)
- dev_queue_xmit_nit(skb, dev);
- ret = dev->hard_start_xmit(skb, dev);
+ ret = dev_hard_start_xmit(skb, dev);
if (ret == NETDEV_TX_OK) {
if (!nolock) {
netif_tx_unlock(dev);
@@ -171,7 +172,10 @@ static inline int qdisc_restart(struct net_device *dev)
*/
requeue:
- q->ops->requeue(skb, q);
+ if (skb->next)
+ dev->gso_skb = skb;
+ else
+ q->ops->requeue(skb, q);
netif_schedule(dev);
return 1;
}
@@ -593,6 +597,11 @@ void dev_deactivate(struct net_device *dev)
/* Wait for outstanding qdisc_run calls. */
while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
yield();
+
+ if (dev->gso_skb) {
+ kfree_skb(dev->gso_skb);
+ dev->gso_skb = NULL;
+ }
}
void dev_init_scheduler(struct net_device *dev)
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