[PATCH 1/2] net: add IFF_SKB_TX_SHARED flag to priv_flags
From: Neil Horman <nhorman@tuxdriver.com>
Date: 2011-07-26 16:05:59
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Pktgen attempts to transmit shared skbs to net devices, which can't be used by some drivers as they keep state information in skbs. This patch adds a flag marking drivers as being able to handle shared skbs in their tx path. Drivers are defaulted to being unable to do so, but calling ether_setup enables this flag, as 90% of the drivers calling ether_setup touch real hardware and can handle shared skbs. A subsequent patch will audit drivers to ensure that the flag is set properly Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jiri Pirko <redacted> CC: Robert Olsson <redacted> CC: Eric Dumazet <redacted> CC: Alexey Dobriyan <redacted> CC: David S. Miller <davem@davemloft.net> --- include/linux/if.h | 2 ++ net/core/pktgen.c | 8 +++++--- net/ethernet/eth.c | 1 + 3 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/include/linux/if.h b/include/linux/if.h
index 3bc63e6..03489ca 100644
--- a/include/linux/if.h
+++ b/include/linux/if.h@@ -76,6 +76,8 @@ #define IFF_BRIDGE_PORT 0x4000 /* device used as bridge port */ #define IFF_OVS_DATAPATH 0x8000 /* device used as Open vSwitch * datapath port */ +#define IFF_TX_SKB_SHARING 0x10000 /* The interface supports sharing + * skbs on transmit */ #define IF_GET_IFACE 0x0001 /* for querying only */ #define IF_GET_PROTO 0x0002
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index f76079c..e35a6fb 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c@@ -1070,7 +1070,9 @@ static ssize_t pktgen_if_write(struct file *file, len = num_arg(&user_buffer[i], 10, &value); if (len < 0) return len; - + if ((value > 0) && + (!(pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING))) + return -ENOTSUPP; i += len; pkt_dev->clone_skb = value;
@@ -3555,7 +3557,6 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname) pkt_dev->min_pkt_size = ETH_ZLEN; pkt_dev->max_pkt_size = ETH_ZLEN; pkt_dev->nfrags = 0; - pkt_dev->clone_skb = pg_clone_skb_d; pkt_dev->delay = pg_delay_d; pkt_dev->count = pg_count_d; pkt_dev->sofar = 0;
@@ -3563,7 +3564,6 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname) pkt_dev->udp_src_max = 9; pkt_dev->udp_dst_min = 9; pkt_dev->udp_dst_max = 9; - pkt_dev->vlan_p = 0; pkt_dev->vlan_cfi = 0; pkt_dev->vlan_id = 0xffff;
@@ -3575,6 +3575,8 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname) err = pktgen_setup_dev(pkt_dev, ifname); if (err) goto out1; + if (pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING) + pkt_dev->clone_skb = pg_clone_skb_d; pkt_dev->entry = proc_create_data(ifname, 0600, pg_proc_dir, &pktgen_if_fops, pkt_dev);
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index 5cffb63..4866330 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c@@ -339,6 +339,7 @@ void ether_setup(struct net_device *dev) dev->addr_len = ETH_ALEN; dev->tx_queue_len = 1000; /* Ethernet wants good queues */ dev->flags = IFF_BROADCAST|IFF_MULTICAST; + dev->priv_flags = IFF_TX_SKB_SHARING; memset(dev->broadcast, 0xFF, ETH_ALEN);
--
1.7.6