net: add IFF_SKB_TX_SHARED flag to priv_flags

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 <jpirko@redhat.com>
CC: Robert Olsson <robert.olsson@its.uu.se>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Alexey Dobriyan <adobriyan@gmail.com>
CC: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Neil Horman 2011-07-26 06:05:37 +00:00 committed by David S. Miller
parent 894dc24ce7
commit d887331506
3 changed files with 8 additions and 3 deletions

View File

@ -76,6 +76,8 @@
#define IFF_BRIDGE_PORT 0x4000 /* device used as bridge port */ #define IFF_BRIDGE_PORT 0x4000 /* device used as bridge port */
#define IFF_OVS_DATAPATH 0x8000 /* device used as Open vSwitch #define IFF_OVS_DATAPATH 0x8000 /* device used as Open vSwitch
* datapath port */ * 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_IFACE 0x0001 /* for querying only */
#define IF_GET_PROTO 0x0002 #define IF_GET_PROTO 0x0002

View File

@ -1070,7 +1070,9 @@ static ssize_t pktgen_if_write(struct file *file,
len = num_arg(&user_buffer[i], 10, &value); len = num_arg(&user_buffer[i], 10, &value);
if (len < 0) if (len < 0)
return len; return len;
if ((value > 0) &&
(!(pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING)))
return -ENOTSUPP;
i += len; i += len;
pkt_dev->clone_skb = value; 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->min_pkt_size = ETH_ZLEN;
pkt_dev->max_pkt_size = ETH_ZLEN; pkt_dev->max_pkt_size = ETH_ZLEN;
pkt_dev->nfrags = 0; pkt_dev->nfrags = 0;
pkt_dev->clone_skb = pg_clone_skb_d;
pkt_dev->delay = pg_delay_d; pkt_dev->delay = pg_delay_d;
pkt_dev->count = pg_count_d; pkt_dev->count = pg_count_d;
pkt_dev->sofar = 0; 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_src_max = 9;
pkt_dev->udp_dst_min = 9; pkt_dev->udp_dst_min = 9;
pkt_dev->udp_dst_max = 9; pkt_dev->udp_dst_max = 9;
pkt_dev->vlan_p = 0; pkt_dev->vlan_p = 0;
pkt_dev->vlan_cfi = 0; pkt_dev->vlan_cfi = 0;
pkt_dev->vlan_id = 0xffff; 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); err = pktgen_setup_dev(pkt_dev, ifname);
if (err) if (err)
goto out1; 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, pkt_dev->entry = proc_create_data(ifname, 0600, pg_proc_dir,
&pktgen_if_fops, pkt_dev); &pktgen_if_fops, pkt_dev);

View File

@ -340,6 +340,7 @@ void ether_setup(struct net_device *dev)
dev->addr_len = ETH_ALEN; dev->addr_len = ETH_ALEN;
dev->tx_queue_len = 1000; /* Ethernet wants good queues */ dev->tx_queue_len = 1000; /* Ethernet wants good queues */
dev->flags = IFF_BROADCAST|IFF_MULTICAST; dev->flags = IFF_BROADCAST|IFF_MULTICAST;
dev->priv_flags = IFF_TX_SKB_SHARING;
memset(dev->broadcast, 0xFF, ETH_ALEN); memset(dev->broadcast, 0xFF, ETH_ALEN);