nfp: don't tell FW about the reserved buffer space

Since commit c0f031bc88 ("nfp_net: use alloc_frag() and build_skb()")
we are allocating buffers which have to hold both the data and skb to
be created in place by build_skb().

FW should only be told about the buffer space it can DMA to, that
is without the build_skb() headroom and tailroom.  Note: firmware
applications should validate the buffers against both MTU and
free list buffer size so oversized packets would not pass through
the NIC anyway.

Fixes: c0f031bc88 ("nfp: use alloc_frag() and build_skb()")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2017-03-02 15:26:20 -08:00 committed by David S. Miller
parent e28599800a
commit 9383b33771
1 changed files with 2 additions and 1 deletions

View File

@ -2198,7 +2198,8 @@ static int __nfp_net_set_config_and_enable(struct nfp_net *nn)
nfp_net_write_mac_addr(nn);
nn_writel(nn, NFP_NET_CFG_MTU, nn->netdev->mtu);
nn_writel(nn, NFP_NET_CFG_FLBUFSZ, nn->fl_bufsz);
nn_writel(nn, NFP_NET_CFG_FLBUFSZ,
nn->fl_bufsz - NFP_NET_RX_BUF_NON_DATA);
/* Enable device */
new_ctrl |= NFP_NET_CFG_CTRL_ENABLE;