diff options
| author | Carl Henrik Lunde <chlunde@ping.uio.no> | 2015-09-16 11:10:04 +0100 |
|---|---|---|
| committer | Michael Brown <mcb30@ipxe.org> | 2015-09-16 11:10:30 +0100 |
| commit | 3f8da985aa81e31b6e9482970f6ec594aecca552 (patch) | |
| tree | e9c84d4f04041fe0621736017e55d92085a3ca0f /src/drivers | |
| parent | 1852803e462b8cdb864d3d07b9c544ef466c22b5 (diff) | |
| download | ipxe-3f8da985aa81e31b6e9482970f6ec594aecca552.tar.gz | |
[vmxnet3] Avoid completely filling the TX descriptor ring
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Diffstat (limited to 'src/drivers')
| -rw-r--r-- | src/drivers/net/vmxnet3.c | 13 | ||||
| -rw-r--r-- | src/drivers/net/vmxnet3.h | 3 |
2 files changed, 12 insertions, 4 deletions
diff --git a/src/drivers/net/vmxnet3.c b/src/drivers/net/vmxnet3.c index 8d4f4b843..6a54dbf89 100644 --- a/src/drivers/net/vmxnet3.c +++ b/src/drivers/net/vmxnet3.c @@ -92,19 +92,24 @@ static int vmxnet3_transmit ( struct net_device *netdev, struct io_buffer *iobuf ) { struct vmxnet3_nic *vmxnet = netdev_priv ( netdev ); struct vmxnet3_tx_desc *tx_desc; + unsigned int fill; unsigned int desc_idx; unsigned int generation; /* Check that we have a free transmit descriptor */ - desc_idx = ( vmxnet->count.tx_prod % VMXNET3_NUM_TX_DESC ); - generation = ( ( vmxnet->count.tx_prod & VMXNET3_NUM_TX_DESC ) ? - 0 : cpu_to_le32 ( VMXNET3_TXF_GEN ) ); - if ( vmxnet->tx_iobuf[desc_idx] ) { + fill = ( vmxnet->count.tx_prod - vmxnet->count.tx_cons ); + if ( fill >= VMXNET3_TX_FILL ) { DBGC ( vmxnet, "VMXNET3 %p out of transmit descriptors\n", vmxnet ); return -ENOBUFS; } + /* Locate transmit descriptor */ + desc_idx = ( vmxnet->count.tx_prod % VMXNET3_NUM_TX_DESC ); + generation = ( ( vmxnet->count.tx_prod & VMXNET3_NUM_TX_DESC ) ? + 0 : cpu_to_le32 ( VMXNET3_TXF_GEN ) ); + assert ( vmxnet->tx_iobuf[desc_idx] == NULL ); + /* Increment producer counter */ vmxnet->count.tx_prod++; diff --git a/src/drivers/net/vmxnet3.h b/src/drivers/net/vmxnet3.h index a1671d9dd..5e1e0cb6e 100644 --- a/src/drivers/net/vmxnet3.h +++ b/src/drivers/net/vmxnet3.h @@ -493,6 +493,9 @@ struct vmxnet3_nic { /** MTU size */ #define VMXNET3_MTU ( ETH_FRAME_LEN + 4 /* VLAN */ + 4 /* FCS */ ) +/** Transmit ring maximum fill level */ +#define VMXNET3_TX_FILL ( VMXNET3_NUM_TX_DESC - 1 ) + /** Receive ring maximum fill level */ #define VMXNET3_RX_FILL 8 |