Commit b5dd884e authored Oct 29, 2009 by Gabor Gombas Committed by David S. Miller Oct 29, 2009

net: Fix 'Re: PACKET_TX_RING: packet size is too long'



Currently PACKET_TX_RING forces certain amount of every frame to remain
unused. This probably originates from an early version of the
PACKET_TX_RING patch that in fact used the extra space when the (since
removed) CONFIG_PACKET_MMAP_ZERO_COPY option was enabled. The current
code does not make any use of this extra space.

This patch removes the extra space reservation and lets userspace make
use of the full frame size.

Signed-off-by: Gabor Gombas <gombasg@sztaki.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 06b71b65

net/packet/af_packet.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -982,10 +982,7 @@ static int tpacket_snd(struct packet_sock po, struct msghdr msg)
		goto out_put;

		size_max = po->tx_ring.frame_size
		- sizeof(struct skb_shared_info)
		- po->tp_hdrlen
		- LL_ALLOCATED_SPACE(dev)
		- sizeof(struct sockaddr_ll);
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));

		if (size_max > dev->mtu + reserve)
		size_max = dev->mtu + reserve;

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