bpf: make virtio compatible w/ bpf_xdp_adjust_tail
authorNikita V. Shirokov <tehnerd@tehnerd.com>
Wed, 18 Apr 2018 04:42:20 +0000 (21:42 -0700)
committerDaniel Borkmann <daniel@iogearbox.net>
Wed, 18 Apr 2018 21:34:16 +0000 (23:34 +0200)
commit6870de435b90c083ae0f3f7f341287976ef56f03
treeed41e09596b241c39f50815ecc686926755096c4
parent8fb58f1ecf5cbcc7805dd339243b7d9837cbabbe
bpf: make virtio compatible w/ bpf_xdp_adjust_tail

w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for virtio driver we need to adjust XDP_PASS handling by recalculating
length of the packet if it was passed to the TCP/IP stack

Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
drivers/net/virtio_net.c