From 06b3e35788a4c6f0afa931b6251ecfe20ce4787b Mon Sep 17 00:00:00 2001
From: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Date: Fri, 16 Mar 2018 20:00:28 -0500
Subject: [PATCH] ibmvnic: Update TX and TX completion routines

References: bsc#1085224
patch-mainline: v4.17-rc1
Git-commit: 06b3e35788a4c6f0afa931b6251ecfe20ce4787b

Update TX and TX completion routines to account for TX pool
restructuring. TX routine first chooses the pool depending
on whether a packet is GSO or not, then uses it accordingly.

For the completion routine to know which pool it needs to use,
set the most significant bit of the correlator index to one
if the packet uses the TSO pool. On completion, unset the bit
and use the correlator index to release the buffer pool entry.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 55 +++++++++++++++++++-------------------
 drivers/net/ethernet/ibm/ibmvnic.h |  1 +
 2 files changed, 29 insertions(+), 27 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 2bb5d562dde1..672e9221d4a5 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -1414,8 +1414,11 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev)
 		ret = NETDEV_TX_OK;
 		goto out;
 	}
+	if (skb_is_gso(skb))
+		tx_pool = &adapter->tso_pool[queue_num];
+	else
+		tx_pool = &adapter->tx_pool[queue_num];
 
-	tx_pool = &adapter->tx_pool[queue_num];
 	tx_scrq = adapter->tx_scrq[queue_num];
 	txq = netdev_get_tx_queue(netdev, skb_get_queue_mapping(skb));
 	handle_array = (u64 *)((u8 *)(adapter->login_rsp_buf) +
@@ -1423,20 +1426,10 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev)
 
 	index = tx_pool->free_map[tx_pool->consumer_index];
 
-	if (skb_is_gso(skb)) {
-		offset = tx_pool->tso_index * IBMVNIC_TSO_BUF_SZ;
-		dst = tx_pool->tso_ltb.buff + offset;
-		memset(dst, 0, IBMVNIC_TSO_BUF_SZ);
-		data_dma_addr = tx_pool->tso_ltb.addr + offset;
-		tx_pool->tso_index++;
-		if (tx_pool->tso_index == IBMVNIC_TSO_BUFS)
-			tx_pool->tso_index = 0;
-	} else {
-		offset = index * (adapter->req_mtu + VLAN_HLEN);
-		dst = tx_pool->long_term_buff.buff + offset;
-		memset(dst, 0, adapter->req_mtu + VLAN_HLEN);
-		data_dma_addr = tx_pool->long_term_buff.addr + offset;
-	}
+	offset = index * tx_pool->buf_size;
+	dst = tx_pool->long_term_buff.buff + offset;
+	memset(dst, 0, tx_pool->buf_size);
+	data_dma_addr = tx_pool->long_term_buff.addr + offset;
 
 	if (skb_shinfo(skb)->nr_frags) {
 		int cur, i;
@@ -1459,8 +1452,7 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev)
 	}
 
 	tx_pool->consumer_index =
-	    (tx_pool->consumer_index + 1) %
-		adapter->req_tx_entries_per_subcrq;
+	    (tx_pool->consumer_index + 1) % tx_pool->num_buffers;
 
 	tx_buff = &tx_pool->tx_buff[index];
 	tx_buff->skb = skb;
@@ -1476,11 +1468,13 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev)
 	tx_crq.v1.n_crq_elem = 1;
 	tx_crq.v1.n_sge = 1;
 	tx_crq.v1.flags1 = IBMVNIC_TX_COMP_NEEDED;
-	tx_crq.v1.correlator = cpu_to_be32(index);
+
 	if (skb_is_gso(skb))
-		tx_crq.v1.dma_reg = cpu_to_be16(tx_pool->tso_ltb.map_id);
+		tx_crq.v1.correlator =
+			cpu_to_be32(index | IBMVNIC_TSO_POOL_MASK);
 	else
-		tx_crq.v1.dma_reg = cpu_to_be16(tx_pool->long_term_buff.map_id);
+		tx_crq.v1.correlator = cpu_to_be32(index);
+	tx_crq.v1.dma_reg = cpu_to_be16(tx_pool->long_term_buff.map_id);
 	tx_crq.v1.sge_len = cpu_to_be32(skb->len);
 	tx_crq.v1.ioba = cpu_to_be64(data_dma_addr);
 
@@ -1543,7 +1537,7 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev)
 
 		if (tx_pool->consumer_index == 0)
 			tx_pool->consumer_index =
-				adapter->req_tx_entries_per_subcrq - 1;
+				tx_pool->num_buffers - 1;
 		else
 			tx_pool->consumer_index--;
 
@@ -2547,6 +2541,7 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter,
 			       struct ibmvnic_sub_crq_queue *scrq)
 {
 	struct device *dev = &adapter->vdev->dev;
+	struct ibmvnic_tx_pool *tx_pool;
 	struct ibmvnic_tx_buff *txbuff;
 	union sub_crq *next;
 	int index;
@@ -2566,7 +2561,14 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter,
 				continue;
 			}
 			index = be32_to_cpu(next->tx_comp.correlators[i]);
-			txbuff = &adapter->tx_pool[pool].tx_buff[index];
+			if (index & IBMVNIC_TSO_POOL_MASK) {
+				tx_pool = &adapter->tso_pool[pool];
+				index &= ~IBMVNIC_TSO_POOL_MASK;
+			} else {
+				tx_pool = &adapter->tx_pool[pool];
+			}
+
+			txbuff = &tx_pool->tx_buff[index];
 
 			for (j = 0; j < IBMVNIC_MAX_FRAGS_PER_CRQ; j++) {
 				if (!txbuff->data_dma[j])
@@ -2589,11 +2591,10 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter,
 
 			num_entries += txbuff->num_entries;
 
-			adapter->tx_pool[pool].free_map[adapter->tx_pool[pool].
-						     producer_index] = index;
-			adapter->tx_pool[pool].producer_index =
-			    (adapter->tx_pool[pool].producer_index + 1) %
-			    adapter->req_tx_entries_per_subcrq;
+			tx_pool->free_map[tx_pool->producer_index] = index;
+			tx_pool->producer_index =
+				(tx_pool->producer_index + 1) %
+					tx_pool->num_buffers;
 		}
 		/* remove tx_comp scrq*/
 		next->tx_comp.first = 0;
diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h
index d287dc78db45..566927e2974a 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.h
+++ b/drivers/net/ethernet/ibm/ibmvnic.h
@@ -43,6 +43,7 @@
 
 #define IBMVNIC_TSO_BUF_SZ	65536
 #define IBMVNIC_TSO_BUFS	64
+#define IBMVNIC_TSO_POOL_MASK	0x80000000
 
 #define IBMVNIC_MAX_LTB_SIZE ((1 << (MAX_ORDER - 1)) * PAGE_SIZE)
 #define IBMVNIC_BUFFER_HLEN 500
-- 
2.13.6