Commit d8873315 authored by Neil Horman's avatar Neil Horman Committed by David S. Miller
Browse files

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: default avatarNeil Horman <nhorman@tuxdriver.com>
Reported-by: default avatarJiri 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: default avatarDavid S. Miller <davem@davemloft.net>
parent 894dc24c

include/linux/if.h

+2 −0
Original line number Diff line number Diff line
@@ -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

net/core/pktgen.c

+5 −3
Original line number Diff line number Diff line
@@ -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);

net/ethernet/eth.c

+1 −0
Original line number Diff line number Diff line
@@ -340,6 +340,7 @@ 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);

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