vmxnet3: add command to set ring buffer sizes

This patch adds a new command to set ring buffer sizes. This is
required to pass the buffer size information to passthrough devices.
For performance reasons, with version7 and later, ring1 will contain
only mtu size buffers (bound to 3K). Packets > 3K will use both ring1
and ring2.

Also, ring sizes are round down to power of 2 and ring2 default
size is increased to 512.

Signed-off-by: Ronak Doshi <doshir@vmware.com>
Acked-by: Guolin Yang <gyang@vmware.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/vmxnet3/vmxnet3_defs.h

@@ -99,6 +99,9 @@ enum {
 	VMXNET3_CMD_SET_COALESCE,
 	VMXNET3_CMD_REGISTER_MEMREGS,
 	VMXNET3_CMD_SET_RSS_FIELDS,
+	VMXNET3_CMD_RESERVED4,
+	VMXNET3_CMD_RESERVED5,
+	VMXNET3_CMD_SET_RING_BUFFER_SIZE,
 
 	VMXNET3_CMD_FIRST_GET = 0xF00D0000,
 	VMXNET3_CMD_GET_QUEUE_STATUS = VMXNET3_CMD_FIRST_GET,
@@ -743,6 +746,13 @@ enum Vmxnet3_RSSField {
 	VMXNET3_RSS_FIELDS_ESPIP6 = 0x0020,
 };
 
+struct Vmxnet3_RingBufferSize {
+	__le16             ring1BufSizeType0;
+	__le16             ring1BufSizeType1;
+	__le16             ring2BufSizeType1;
+	__le16             pad;
+};
+
 /* If the command data <= 16 bytes, use the shared memory directly.
  * otherwise, use variable length configuration descriptor.
  */
@@ -750,6 +760,7 @@ union Vmxnet3_CmdInfo {
 	struct Vmxnet3_VariableLenConfDesc	varConf;
 	struct Vmxnet3_SetPolling		setPolling;
 	enum   Vmxnet3_RSSField                 setRssFields;
+	struct Vmxnet3_RingBufferSize           ringBufSize;
 	__le64					data[2];
 };
 

drivers/net/vmxnet3/vmxnet3_drv.c

@@ -2680,6 +2680,23 @@ vmxnet3_setup_driver_shared(struct vmxnet3_adapter *adapter)
 	/* the rest are already zeroed */
 }
 
+static void
+vmxnet3_init_bufsize(struct vmxnet3_adapter *adapter)
+{
+	struct Vmxnet3_DriverShared *shared = adapter->shared;
+	union Vmxnet3_CmdInfo *cmdInfo = &shared->cu.cmdInfo;
+	unsigned long flags;
+
+	if (!VMXNET3_VERSION_GE_7(adapter))
+		return;
+
+	cmdInfo->ringBufSize = adapter->ringBufSize;
+	spin_lock_irqsave(&adapter->cmd_lock, flags);
+	VMXNET3_WRITE_BAR1_REG(adapter, VMXNET3_REG_CMD,
+			       VMXNET3_CMD_SET_RING_BUFFER_SIZE);
+	spin_unlock_irqrestore(&adapter->cmd_lock, flags);
+}
+
 static void
 vmxnet3_init_coalesce(struct vmxnet3_adapter *adapter)
 {
@@ -2818,6 +2835,7 @@ vmxnet3_activate_dev(struct vmxnet3_adapter *adapter)
 		goto activate_err;
 	}
 
+	vmxnet3_init_bufsize(adapter);
 	vmxnet3_init_coalesce(adapter);
 	vmxnet3_init_rssfields(adapter);
 
@@ -2991,6 +3009,8 @@ static void
 vmxnet3_adjust_rx_ring_size(struct vmxnet3_adapter *adapter)
 {
 	size_t sz, i, ring0_size, ring1_size, comp_size;
+	/* With version7 ring1 will have only T0 buffers */
+	if (!VMXNET3_VERSION_GE_7(adapter)) {
 		if (adapter->netdev->mtu <= VMXNET3_MAX_SKB_BUF_SIZE -
 					    VMXNET3_MAX_ETH_HDR_SIZE) {
 			adapter->skb_buf_size = adapter->netdev->mtu +
@@ -3005,6 +3025,14 @@ vmxnet3_adjust_rx_ring_size(struct vmxnet3_adapter *adapter)
 						    VMXNET3_MAX_ETH_HDR_SIZE;
 			adapter->rx_buf_per_pkt = 1 + (sz + PAGE_SIZE - 1) / PAGE_SIZE;
 		}
+	} else {
+		adapter->skb_buf_size = min((int)adapter->netdev->mtu + VMXNET3_MAX_ETH_HDR_SIZE,
+					    VMXNET3_MAX_SKB_BUF_SIZE);
+		adapter->rx_buf_per_pkt = 1;
+		adapter->ringBufSize.ring1BufSizeType0 = cpu_to_le16(adapter->skb_buf_size);
+		adapter->ringBufSize.ring1BufSizeType1 = 0;
+		adapter->ringBufSize.ring2BufSizeType1 = cpu_to_le16(PAGE_SIZE);
+	}
 
 	/*
 	 * for simplicity, force the ring0 size to be a multiple of
@@ -3019,6 +3047,11 @@ vmxnet3_adjust_rx_ring_size(struct vmxnet3_adapter *adapter)
 	ring1_size = (ring1_size + sz - 1) / sz * sz;
 	ring1_size = min_t(u32, ring1_size, VMXNET3_RX_RING2_MAX_SIZE /
 			   sz * sz);
+	/* For v7 and later, keep ring size power of 2 for UPT */
+	if (VMXNET3_VERSION_GE_7(adapter)) {
+		ring0_size = rounddown_pow_of_two(ring0_size);
+		ring1_size = rounddown_pow_of_two(ring1_size);
+	}
 	comp_size = ring0_size + ring1_size;
 
 	for (i = 0; i < adapter->num_rx_queues; i++) {

drivers/net/vmxnet3/vmxnet3_ethtool.c

@@ -718,6 +718,13 @@ vmxnet3_set_ringparam(struct net_device *netdev,
 	new_rx_ring2_size = min_t(u32, new_rx_ring2_size,
 				  VMXNET3_RX_RING2_MAX_SIZE);
 
+	/* For v7 and later, keep ring size power of 2 for UPT */
+	if (VMXNET3_VERSION_GE_7(adapter)) {
+		new_tx_ring_size = rounddown_pow_of_two(new_tx_ring_size);
+		new_rx_ring_size = rounddown_pow_of_two(new_rx_ring_size);
+		new_rx_ring2_size = rounddown_pow_of_two(new_rx_ring2_size);
+	}
+
 	/* rx data ring buffer size has to be a multiple of
 	 * VMXNET3_RXDATA_DESC_SIZE_ALIGN
 	 */

drivers/net/vmxnet3/vmxnet3_int.h

@@ -408,6 +408,7 @@ struct vmxnet3_adapter {
 	dma_addr_t pm_conf_pa;
 	dma_addr_t rss_conf_pa;
 	bool   queuesExtEnabled;
+	struct Vmxnet3_RingBufferSize     ringBufSize;
 	u32    devcap_supported[8];
 	u32    ptcap_supported[8];
 	u32    dev_caps[8];
@@ -449,7 +450,7 @@ struct vmxnet3_adapter {
 /* must be a multiple of VMXNET3_RING_SIZE_ALIGN */
 #define VMXNET3_DEF_TX_RING_SIZE    512
 #define VMXNET3_DEF_RX_RING_SIZE    1024
-#define VMXNET3_DEF_RX_RING2_SIZE   256
+#define VMXNET3_DEF_RX_RING2_SIZE   512
 
 #define VMXNET3_DEF_RXDATA_DESC_SIZE 128