[PATCH net-next v4 3/7] vmxnet3: allow variable length transmit data ring buffer

From: Shrikrishna Khare
Date: Tue Jun 14 2016 - 14:54:17 EST


Signed-off-by: Sriram Rangarajan <rangarajans@xxxxxxxxxx>
Signed-off-by: Shrikrishna Khare <skhare@xxxxxxxxxx>
---
drivers/net/vmxnet3/vmxnet3_defs.h | 12 +++++++-
drivers/net/vmxnet3/vmxnet3_drv.c | 55 ++++++++++++++++++++++++++---------
drivers/net/vmxnet3/vmxnet3_ethtool.c | 9 +++---
drivers/net/vmxnet3/vmxnet3_int.h | 7 ++++-
4 files changed, 64 insertions(+), 19 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_defs.h b/drivers/net/vmxnet3/vmxnet3_defs.h
index a26a69d..701d989 100644
--- a/drivers/net/vmxnet3/vmxnet3_defs.h
+++ b/drivers/net/vmxnet3/vmxnet3_defs.h
@@ -92,6 +92,7 @@ enum {
VMXNET3_CMD_GET_DEV_EXTRA_INFO,
VMXNET3_CMD_GET_CONF_INTR,
VMXNET3_CMD_GET_RESERVED1,
+ VMXNET3_CMD_GET_TXDATA_DESC_SIZE
};

/*
@@ -377,6 +378,10 @@ union Vmxnet3_GenericDesc {
#define VMXNET3_RING_SIZE_ALIGN 32
#define VMXNET3_RING_SIZE_MASK (VMXNET3_RING_SIZE_ALIGN - 1)

+/* Tx Data Ring buffer size must be a multiple of 64 */
+#define VMXNET3_TXDATA_DESC_SIZE_ALIGN 64
+#define VMXNET3_TXDATA_DESC_SIZE_MASK (VMXNET3_TXDATA_DESC_SIZE_ALIGN - 1)
+
/* Max ring size */
#define VMXNET3_TX_RING_MAX_SIZE 4096
#define VMXNET3_TC_RING_MAX_SIZE 4096
@@ -384,6 +389,9 @@ union Vmxnet3_GenericDesc {
#define VMXNET3_RX_RING2_MAX_SIZE 4096
#define VMXNET3_RC_RING_MAX_SIZE 8192

+#define VMXNET3_TXDATA_DESC_MIN_SIZE 128
+#define VMXNET3_TXDATA_DESC_MAX_SIZE 2048
+
/* a list of reasons for queue stop */

enum {
@@ -470,7 +478,9 @@ struct Vmxnet3_TxQueueConf {
__le32 compRingSize; /* # of comp desc */
__le32 ddLen; /* size of driver data */
u8 intrIdx;
- u8 _pad[7];
+ u8 _pad1[1];
+ __le16 txDataRingDescSize;
+ u8 _pad2[4];
};


diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index 507c53d..4e42eb0 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -435,8 +435,8 @@ vmxnet3_tq_destroy(struct vmxnet3_tx_queue *tq,
tq->tx_ring.base = NULL;
}
if (tq->data_ring.base) {
- dma_free_coherent(&adapter->pdev->dev, tq->data_ring.size *
- sizeof(struct Vmxnet3_TxDataDesc),
+ dma_free_coherent(&adapter->pdev->dev,
+ tq->data_ring.size * tq->txdata_desc_size,
tq->data_ring.base, tq->data_ring.basePA);
tq->data_ring.base = NULL;
}
@@ -478,8 +478,8 @@ vmxnet3_tq_init(struct vmxnet3_tx_queue *tq,
tq->tx_ring.next2fill = tq->tx_ring.next2comp = 0;
tq->tx_ring.gen = VMXNET3_INIT_GEN;

- memset(tq->data_ring.base, 0, tq->data_ring.size *
- sizeof(struct Vmxnet3_TxDataDesc));
+ memset(tq->data_ring.base, 0,
+ tq->data_ring.size * tq->txdata_desc_size);

/* reset the tx comp ring contents to 0 and reset comp ring states */
memset(tq->comp_ring.base, 0, tq->comp_ring.size *
@@ -514,10 +514,10 @@ vmxnet3_tq_create(struct vmxnet3_tx_queue *tq,
}

tq->data_ring.base = dma_alloc_coherent(&adapter->pdev->dev,
- tq->data_ring.size * sizeof(struct Vmxnet3_TxDataDesc),
+ tq->data_ring.size * tq->txdata_desc_size,
&tq->data_ring.basePA, GFP_KERNEL);
if (!tq->data_ring.base) {
- netdev_err(adapter->netdev, "failed to allocate data ring\n");
+ netdev_err(adapter->netdev, "failed to allocate tx data ring\n");
goto err;
}

@@ -689,7 +689,7 @@ vmxnet3_map_pkt(struct sk_buff *skb, struct vmxnet3_tx_ctx *ctx,
if (ctx->copy_size) {
ctx->sop_txd->txd.addr = cpu_to_le64(tq->data_ring.basePA +
tq->tx_ring.next2fill *
- sizeof(struct Vmxnet3_TxDataDesc));
+ tq->txdata_desc_size);
ctx->sop_txd->dword[2] = cpu_to_le32(dw2 | ctx->copy_size);
ctx->sop_txd->dword[3] = 0;

@@ -873,8 +873,9 @@ vmxnet3_parse_hdr(struct sk_buff *skb, struct vmxnet3_tx_queue *tq,
ctx->eth_ip_hdr_size = 0;
ctx->l4_hdr_size = 0;
/* copy as much as allowed */
- ctx->copy_size = min((unsigned int)VMXNET3_HDR_COPY_SIZE
- , skb_headlen(skb));
+ ctx->copy_size = min_t(unsigned int,
+ tq->txdata_desc_size,
+ skb_headlen(skb));
}

if (skb->len <= VMXNET3_HDR_COPY_SIZE)
@@ -885,7 +886,7 @@ vmxnet3_parse_hdr(struct sk_buff *skb, struct vmxnet3_tx_queue *tq,
goto err;
}

- if (unlikely(ctx->copy_size > VMXNET3_HDR_COPY_SIZE)) {
+ if (unlikely(ctx->copy_size > tq->txdata_desc_size)) {
tq->stats.oversized_hdr++;
ctx->copy_size = 0;
return 0;
@@ -2336,6 +2337,7 @@ vmxnet3_setup_driver_shared(struct vmxnet3_adapter *adapter)
tqc->ddPA = cpu_to_le64(tq->buf_info_pa);
tqc->txRingSize = cpu_to_le32(tq->tx_ring.size);
tqc->dataRingSize = cpu_to_le32(tq->data_ring.size);
+ tqc->txDataRingDescSize = cpu_to_le32(tq->txdata_desc_size);
tqc->compRingSize = cpu_to_le32(tq->comp_ring.size);
tqc->ddLen = cpu_to_le32(
sizeof(struct vmxnet3_tx_buf_info) *
@@ -2689,7 +2691,8 @@ vmxnet3_adjust_rx_ring_size(struct vmxnet3_adapter *adapter)

int
vmxnet3_create_queues(struct vmxnet3_adapter *adapter, u32 tx_ring_size,
- u32 rx_ring_size, u32 rx_ring2_size)
+ u32 rx_ring_size, u32 rx_ring2_size,
+ u16 txdata_desc_size)
{
int err = 0, i;

@@ -2698,6 +2701,7 @@ vmxnet3_create_queues(struct vmxnet3_adapter *adapter, u32 tx_ring_size,
tq->tx_ring.size = tx_ring_size;
tq->data_ring.size = tx_ring_size;
tq->comp_ring.size = tx_ring_size;
+ tq->txdata_desc_size = txdata_desc_size;
tq->shared = &adapter->tqd_start[i].ctrl;
tq->stopped = true;
tq->adapter = adapter;
@@ -2754,9 +2758,34 @@ vmxnet3_open(struct net_device *netdev)
for (i = 0; i < adapter->num_tx_queues; i++)
spin_lock_init(&adapter->tx_queue[i].tx_lock);

- err = vmxnet3_create_queues(adapter, adapter->tx_ring_size,
+ if (VMXNET3_VERSION_GE_3(adapter)) {
+ unsigned long flags;
+ u16 txdata_desc_size;
+
+ spin_lock_irqsave(&adapter->cmd_lock, flags);
+ VMXNET3_WRITE_BAR1_REG(adapter, VMXNET3_REG_CMD,
+ VMXNET3_CMD_GET_TXDATA_DESC_SIZE);
+ txdata_desc_size = VMXNET3_READ_BAR1_REG(adapter,
+ VMXNET3_REG_CMD);
+ spin_unlock_irqrestore(&adapter->cmd_lock, flags);
+
+ if ((txdata_desc_size < VMXNET3_TXDATA_DESC_MIN_SIZE) ||
+ (txdata_desc_size > VMXNET3_TXDATA_DESC_MAX_SIZE) ||
+ (txdata_desc_size & VMXNET3_TXDATA_DESC_SIZE_MASK)) {
+ adapter->txdata_desc_size =
+ sizeof(struct Vmxnet3_TxDataDesc);
+ } else {
+ adapter->txdata_desc_size = txdata_desc_size;
+ }
+ } else {
+ adapter->txdata_desc_size = sizeof(struct Vmxnet3_TxDataDesc);
+ }
+
+ err = vmxnet3_create_queues(adapter,
+ adapter->tx_ring_size,
adapter->rx_ring_size,
- adapter->rx_ring2_size);
+ adapter->rx_ring2_size,
+ adapter->txdata_desc_size);
if (err)
goto queue_err;

diff --git a/drivers/net/vmxnet3/vmxnet3_ethtool.c b/drivers/net/vmxnet3/vmxnet3_ethtool.c
index 163e99c..3b70cfe 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethtool.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethtool.c
@@ -396,8 +396,7 @@ vmxnet3_get_regs(struct net_device *netdev, struct ethtool_regs *regs, void *p)
buf[j++] = VMXNET3_GET_ADDR_LO(tq->data_ring.basePA);
buf[j++] = VMXNET3_GET_ADDR_HI(tq->data_ring.basePA);
buf[j++] = tq->data_ring.size;
- /* transmit data ring buffer size */
- buf[j++] = VMXNET3_HDR_COPY_SIZE;
+ buf[j++] = tq->txdata_desc_size;

buf[j++] = VMXNET3_GET_ADDR_LO(tq->comp_ring.basePA);
buf[j++] = VMXNET3_GET_ADDR_HI(tq->comp_ring.basePA);
@@ -591,7 +590,8 @@ vmxnet3_set_ringparam(struct net_device *netdev,
vmxnet3_rq_destroy_all(adapter);

err = vmxnet3_create_queues(adapter, new_tx_ring_size,
- new_rx_ring_size, new_rx_ring2_size);
+ new_rx_ring_size, new_rx_ring2_size,
+ adapter->txdata_desc_size);

if (err) {
/* failed, most likely because of OOM, try default
@@ -604,7 +604,8 @@ vmxnet3_set_ringparam(struct net_device *netdev,
err = vmxnet3_create_queues(adapter,
new_tx_ring_size,
new_rx_ring_size,
- new_rx_ring2_size);
+ new_rx_ring2_size,
+ adapter->txdata_desc_size);
if (err) {
netdev_err(netdev, "failed to create queues "
"with default sizes. Closing it\n");
diff --git a/drivers/net/vmxnet3/vmxnet3_int.h b/drivers/net/vmxnet3/vmxnet3_int.h
index de068e9..94010de 100644
--- a/drivers/net/vmxnet3/vmxnet3_int.h
+++ b/drivers/net/vmxnet3/vmxnet3_int.h
@@ -241,6 +241,7 @@ struct vmxnet3_tx_queue {
int num_stop; /* # of times the queue is
* stopped */
int qid;
+ u16 txdata_desc_size;
} __attribute__((__aligned__(SMP_CACHE_BYTES)));

enum vmxnet3_rx_buf_type {
@@ -363,6 +364,9 @@ struct vmxnet3_adapter {
u32 rx_ring_size;
u32 rx_ring2_size;

+ /* Size of buffer in the data ring */
+ u16 txdata_desc_size;
+
struct work_struct work;

unsigned long state; /* VMXNET3_STATE_BIT_xxx */
@@ -427,7 +431,8 @@ vmxnet3_set_features(struct net_device *netdev, netdev_features_t features);

int
vmxnet3_create_queues(struct vmxnet3_adapter *adapter,
- u32 tx_ring_size, u32 rx_ring_size, u32 rx_ring2_size);
+ u32 tx_ring_size, u32 rx_ring_size, u32 rx_ring2_size,
+ u16 txdata_desc_size);

void vmxnet3_set_ethtool_ops(struct net_device *netdev);

--
2.8.2