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 <bhutchings@solarflare.com>
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index f52b38c..e85bed0 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -263,6 +263,7 @@
#define EFX_RX_PKT_CSUMMED 0x0002
#define EFX_RX_PKT_DISCARD 0x0004
#define EFX_RX_PKT_TCP 0x0040
+#define EFX_RX_PKT_PREFIX_LEN 0x0080 /* length is in prefix only */
/**
* struct efx_rx_page_state - Page-based rx buffer state
@@ -668,6 +669,8 @@
* @rx_prefix_size: Size of RX prefix before packet data
* @rx_packet_hash_offset: Offset of RX flow hash from start of packet data
* (valid only if @rx_prefix_size != 0; always negative)
+ * @rx_packet_len_offset: Offset of RX packet length from start of packet data
+ * (valid only for NICs that set %EFX_RX_PKT_PREFIX_LEN; always negative)
* @rx_hash_key: Toeplitz hash key for RSS
* @rx_indir_table: Indirection table for RSS
* @rx_scatter: Scatter mode enabled for receives
@@ -800,6 +803,7 @@
unsigned int rx_pages_per_batch;
unsigned int rx_prefix_size;
int rx_packet_hash_offset;
+ int rx_packet_len_offset;
u8 rx_hash_key[40];
u32 rx_indir_table[128];
bool rx_scatter;