From 3dced740c243f454a9b83fbe73133911d5c6ce8d Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sat, 27 Apr 2013 01:55:18 +0100 Subject: sfc: Add support for reading packet length from prefix Define a flag for struct efx_rx_buffer and efx_rx_packet() that indicates packet length must be read from the prefix. If this is set, read the length in __efx_rx_packet() (when the prefix should have arrived in cache). Signed-off-by: Ben Hutchings --- drivers/net/ethernet/sfc/rx.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'drivers/net/ethernet/sfc/rx.c') diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c index 7646bb3c926d..864b6ffc9cb2 100644 --- a/drivers/net/ethernet/sfc/rx.c +++ b/drivers/net/ethernet/sfc/rx.c @@ -526,7 +526,8 @@ void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index, /* Validate the number of fragments and completed length */ if (n_frags == 1) { - efx_rx_packet__check_len(rx_queue, rx_buf, len); + if (!(flags & EFX_RX_PKT_PREFIX_LEN)) + efx_rx_packet__check_len(rx_queue, rx_buf, len); } else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) || unlikely(len <= (n_frags - 1) * EFX_RX_USR_BUF_SIZE) || unlikely(len > n_frags * EFX_RX_USR_BUF_SIZE) || @@ -554,7 +555,7 @@ void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index, return; } - if (n_frags == 1) + if (n_frags == 1 && !(flags & EFX_RX_PKT_PREFIX_LEN)) rx_buf->len = len; /* Release and/or sync the DMA mapping - assumes all RX buffers @@ -633,6 +634,13 @@ void __efx_rx_packet(struct efx_channel *channel) efx_rx_buffer(&channel->rx_queue, channel->rx_pkt_index); u8 *eh = efx_rx_buf_va(rx_buf); + /* Read length from the prefix if necessary. This already + * excludes the length of the prefix itself. + */ + if (rx_buf->flags & EFX_RX_PKT_PREFIX_LEN) + rx_buf->len = le16_to_cpup((__le16 *) + (eh + efx->rx_packet_len_offset)); + /* If we're in loopback test, then pass the packet directly to the * loopback layer, and free the rx_buf here */ -- cgit v1.2.3-59-g8ed1b