[PATCH v2 net-next] liquidio: improve UDP TX performance

[Felix Manlunas <felix.manlunas@cavium.com>]

From: VSR Burru <veerasenareddy.burru@cavium.com>

Improve UDP TX performance by:
* reducing the ring size from 2K to 512
* replacing the numerous streaming DMA allocations for info buffers and
  gather lists with one large consistent DMA allocation per ring

Netperf benchmark numbers before and after patch:

PF UDP TX
+--------+--------+------------+------------+---------+
|        |        |  Before    |  After     |         |
| Number |        |  Patch     |  Patch     |         |
|  of    | Packet | Throughput | Throughput | Percent |
| Flows  |  Size  |  (Gbps)    |  (Gbps)    | Change  |
+--------+--------+------------+------------+---------+
|        |   360  |   0.52     |   0.93     |  +78.9  |
|   1    |  1024  |   1.62     |   2.84     |  +75.3  |
|        |  1518  |   2.44     |   4.21     |  +72.5  |
+--------+--------+------------+------------+---------+
|        |   360  |   0.45     |   1.59     | +253.3  |
|   4    |  1024  |   1.34     |   5.48     | +308.9  |
|        |  1518  |   2.27     |   8.31     | +266.1  |
+--------+--------+------------+------------+---------+
|        |   360  |   0.40     |   1.61     | +302.5  |
|   8    |  1024  |   1.64     |   4.24     | +158.5  |
|        |  1518  |   2.87     |   6.52     | +127.2  |
+--------+--------+------------+------------+---------+


VF UDP TX
+--------+--------+------------+------------+---------+
|        |        |  Before    |  After     |         |
| Number |        |  Patch     |  Patch     |         |
|  of    | Packet | Throughput | Throughput | Percent |
| Flows  |  Size  |  (Gbps)    |  (Gbps)    | Change  |
+--------+--------+------------+------------+---------+
|        |   360  |   1.28     |   1.49     |  +16.4  |
|   1    |  1024  |   4.44     |   4.39     |   -1.1  |
|        |  1518  |   6.08     |   6.51     |   +7.1  |
+--------+--------+------------+------------+---------+
|        |   360  |   2.35     |   2.35     |    0.0  |
|   4    |  1024  |   6.41     |   8.07     |  +25.9  |
|        |  1518  |   9.56     |   9.54     |   -0.2  |
+--------+--------+------------+------------+---------+
|        |   360  |   3.41     |   3.65     |   +7.0  |
|   8    |  1024  |   9.35     |   9.34     |   -0.1  |
|        |  1518  |   9.56     |   9.57     |   +0.1  |
+--------+--------+------------+------------+---------+

Signed-off-by: VSR Burru <veerasenareddy.burru@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: Derek Chickles <derek.chickles@cavium.com>
Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
---
Patch Changlog:
 v2: Add before and after benchmark numbers to the patch explanation.

 drivers/net/ethernet/cavium/liquidio/lio_main.c    | 110 ++++++++++-----------
 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c | 104 ++++++++++---------
 .../net/ethernet/cavium/liquidio/octeon_config.h   |   6 +-
 drivers/net/ethernet/cavium/liquidio/octeon_droq.c |  17 +---
 drivers/net/ethernet/cavium/liquidio/octeon_droq.h |   4 +-
 drivers/net/ethernet/cavium/liquidio/octeon_main.h |  42 --------
 .../net/ethernet/cavium/liquidio/octeon_network.h  |  43 +++++---
 7 files changed, 144 insertions(+), 182 deletions(-)

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_main.c b/drivers/net/ethernet/cavium/liquidio/lio_main.c
index be9c0e3..92f46b1 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c
@@ -152,7 +152,7 @@ struct octnic_gather {
 	 */
 	struct octeon_sg_entry *sg;
 
-	u64 sg_dma_ptr;
+	dma_addr_t sg_dma_ptr;
 };
 
 struct handshake {
@@ -734,6 +734,9 @@ static void delete_glists(struct lio *lio)
 	struct octnic_gather *g;
 	int i;
 
+	kfree(lio->glist_lock);
+	lio->glist_lock = NULL;
+
 	if (!lio->glist)
 		return;
 
@@ -741,23 +744,26 @@ static void delete_glists(struct lio *lio)
 		do {
 			g = (struct octnic_gather *)
 				list_delete_head(&lio->glist[i]);
-			if (g) {
-				if (g->sg) {
-					dma_unmap_single(&lio->oct_dev->
-							 pci_dev->dev,
-							 g->sg_dma_ptr,
-							 g->sg_size,
-							 DMA_TO_DEVICE);
-					kfree((void *)((unsigned long)g->sg -
-						       g->adjust));
-				}
+			if (g)
 				kfree(g);
-			}
 		} while (g);
+
+		if (lio->glists_virt_base && lio->glists_virt_base[i]) {
+			lio_dma_free(lio->oct_dev,
+				     lio->glist_entry_size * lio->tx_qsize,
+				     lio->glists_virt_base[i],
+				     lio->glists_dma_base[i]);
+		}
 	}
 
-	kfree((void *)lio->glist);
-	kfree((void *)lio->glist_lock);
+	kfree(lio->glists_virt_base);
+	lio->glists_virt_base = NULL;
+
+	kfree(lio->glists_dma_base);
+	lio->glists_dma_base = NULL;
+
+	kfree(lio->glist);
+	lio->glist = NULL;
 }
 
 /**
@@ -772,13 +778,30 @@ static int setup_glists(struct octeon_device *oct, struct lio *lio, int num_iqs)
 	lio->glist_lock = kcalloc(num_iqs, sizeof(*lio->glist_lock),
 				  GFP_KERNEL);
 	if (!lio->glist_lock)
-		return 1;
+		return -ENOMEM;
 
 	lio->glist = kcalloc(num_iqs, sizeof(*lio->glist),
 			     GFP_KERNEL);
 	if (!lio->glist) {
-		kfree((void *)lio->glist_lock);
-		return 1;
+		kfree(lio->glist_lock);
+		lio->glist_lock = NULL;
+		return -ENOMEM;
+	}
+
+	lio->glist_entry_size =
+		ROUNDUP8((ROUNDUP4(OCTNIC_MAX_SG) >> 2) * OCT_SG_ENTRY_SIZE);
+
+	/* allocate memory to store virtual and dma base address of
+	 * per glist consistent memory
+	 */
+	lio->glists_virt_base = kcalloc(num_iqs, sizeof(*lio->glists_virt_base),
+					GFP_KERNEL);
+	lio->glists_dma_base = kcalloc(num_iqs, sizeof(*lio->glists_dma_base),
+				       GFP_KERNEL);
+
+	if (!lio->glists_virt_base || !lio->glists_dma_base) {
+		delete_glists(lio);
+		return -ENOMEM;
 	}
 
 	for (i = 0; i < num_iqs; i++) {
@@ -788,6 +811,16 @@ static int setup_glists(struct octeon_device *oct, struct lio *lio, int num_iqs)
 
 		INIT_LIST_HEAD(&lio->glist[i]);
 
+		lio->glists_virt_base[i] =
+			lio_dma_alloc(oct,
+				      lio->glist_entry_size * lio->tx_qsize,
+				      &lio->glists_dma_base[i]);
+
+		if (!lio->glists_virt_base[i]) {
+			delete_glists(lio);
+			return -ENOMEM;
+		}
+
 		for (j = 0; j < lio->tx_qsize; j++) {
 			g = kzalloc_node(sizeof(*g), GFP_KERNEL,
 					 numa_node);
@@ -796,43 +829,18 @@ static int setup_glists(struct octeon_device *oct, struct lio *lio, int num_iqs)
 			if (!g)
 				break;
 
-			g->sg_size = ((ROUNDUP4(OCTNIC_MAX_SG) >> 2) *
-				      OCT_SG_ENTRY_SIZE);
+			g->sg = lio->glists_virt_base[i] +
+				(j * lio->glist_entry_size);
 
-			g->sg = kmalloc_node(g->sg_size + 8,
-					     GFP_KERNEL, numa_node);
-			if (!g->sg)
-				g->sg = kmalloc(g->sg_size + 8, GFP_KERNEL);
-			if (!g->sg) {
-				kfree(g);
-				break;
-			}
-
-			/* The gather component should be aligned on 64-bit
-			 * boundary
-			 */
-			if (((unsigned long)g->sg) & 7) {
-				g->adjust = 8 - (((unsigned long)g->sg) & 7);
-				g->sg = (struct octeon_sg_entry *)
-					((unsigned long)g->sg + g->adjust);
-			}
-			g->sg_dma_ptr = dma_map_single(&oct->pci_dev->dev,
-						       g->sg, g->sg_size,
-						       DMA_TO_DEVICE);
-			if (dma_mapping_error(&oct->pci_dev->dev,
-					      g->sg_dma_ptr)) {
-				kfree((void *)((unsigned long)g->sg -
-					       g->adjust));
-				kfree(g);
-				break;
-			}
+			g->sg_dma_ptr = lio->glists_dma_base[i] +
+					(j * lio->glist_entry_size);
 
 			list_add_tail(&g->list, &lio->glist[i]);
 		}
 
 		if (j != lio->tx_qsize) {
 			delete_glists(lio);
-			return 1;
+			return -ENOMEM;
 		}
 	}
 
@@ -1885,9 +1893,6 @@ static void free_netsgbuf(void *buf)
 		i++;
 	}
 
-	dma_sync_single_for_cpu(&lio->oct_dev->pci_dev->dev,
-				g->sg_dma_ptr, g->sg_size, DMA_TO_DEVICE);
-
 	iq = skb_iq(lio, skb);
 	spin_lock(&lio->glist_lock[iq]);
 	list_add_tail(&g->list, &lio->glist[iq]);
@@ -1933,9 +1938,6 @@ static void free_netsgbuf_with_resp(void *buf)
 		i++;
 	}
 
-	dma_sync_single_for_cpu(&lio->oct_dev->pci_dev->dev,
-				g->sg_dma_ptr, g->sg_size, DMA_TO_DEVICE);
-
 	iq = skb_iq(lio, skb);
 
 	spin_lock(&lio->glist_lock[iq]);
@@ -3273,8 +3275,6 @@ static int liquidio_xmit(struct sk_buff *skb, struct net_device *netdev)
 			i++;
 		}
 
-		dma_sync_single_for_device(&oct->pci_dev->dev, g->sg_dma_ptr,
-					   g->sg_size, DMA_TO_DEVICE);
 		dptr = g->sg_dma_ptr;
 
 		if (OCTEON_CN23XX_PF(oct))
diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
index 9d5e035..7b83be4 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
@@ -108,6 +108,8 @@ struct octnic_gather {
 	 * received from the IP layer.
 	 */
 	struct octeon_sg_entry *sg;
+
+	dma_addr_t sg_dma_ptr;
 };
 
 struct octeon_device_priv {
@@ -490,6 +492,9 @@ static void delete_glists(struct lio *lio)
 	struct octnic_gather *g;
 	int i;
 
+	kfree(lio->glist_lock);
+	lio->glist_lock = NULL;
+
 	if (!lio->glist)
 		return;
 
@@ -497,17 +502,26 @@ static void delete_glists(struct lio *lio)
 		do {
 			g = (struct octnic_gather *)
 			    list_delete_head(&lio->glist[i]);
-			if (g) {
-				if (g->sg)
-					kfree((void *)((unsigned long)g->sg -
-							g->adjust));
+			if (g)
 				kfree(g);
-			}
 		} while (g);
+
+		if (lio->glists_virt_base && lio->glists_virt_base[i]) {
+			lio_dma_free(lio->oct_dev,
+				     lio->glist_entry_size * lio->tx_qsize,
+				     lio->glists_virt_base[i],
+				     lio->glists_dma_base[i]);
+		}
 	}
 
+	kfree(lio->glists_virt_base);
+	lio->glists_virt_base = NULL;
+
+	kfree(lio->glists_dma_base);
+	lio->glists_dma_base = NULL;
+
 	kfree(lio->glist);
-	kfree(lio->glist_lock);
+	lio->glist = NULL;
 }
 
 /**
@@ -522,13 +536,30 @@ static int setup_glists(struct lio *lio, int num_iqs)
 	lio->glist_lock =
 	    kzalloc(sizeof(*lio->glist_lock) * num_iqs, GFP_KERNEL);
 	if (!lio->glist_lock)
-		return 1;
+		return -ENOMEM;
 
 	lio->glist =
 	    kzalloc(sizeof(*lio->glist) * num_iqs, GFP_KERNEL);
 	if (!lio->glist) {
 		kfree(lio->glist_lock);
-		return 1;
+		lio->glist_lock = NULL;
+		return -ENOMEM;
+	}
+
+	lio->glist_entry_size =
+		ROUNDUP8((ROUNDUP4(OCTNIC_MAX_SG) >> 2) * OCT_SG_ENTRY_SIZE);
+
+	/* allocate memory to store virtual and dma base address of
+	 * per glist consistent memory
+	 */
+	lio->glists_virt_base = kcalloc(num_iqs, sizeof(*lio->glists_virt_base),
+					GFP_KERNEL);
+	lio->glists_dma_base = kcalloc(num_iqs, sizeof(*lio->glists_dma_base),
+				       GFP_KERNEL);
+
+	if (!lio->glists_virt_base || !lio->glists_dma_base) {
+		delete_glists(lio);
+		return -ENOMEM;
 	}
 
 	for (i = 0; i < num_iqs; i++) {
@@ -536,34 +567,33 @@ static int setup_glists(struct lio *lio, int num_iqs)
 
 		INIT_LIST_HEAD(&lio->glist[i]);
 
+		lio->glists_virt_base[i] =
+			lio_dma_alloc(lio->oct_dev,
+				      lio->glist_entry_size * lio->tx_qsize,
+				      &lio->glists_dma_base[i]);
+
+		if (!lio->glists_virt_base[i]) {
+			delete_glists(lio);
+			return -ENOMEM;
+		}
+
 		for (j = 0; j < lio->tx_qsize; j++) {
 			g = kzalloc(sizeof(*g), GFP_KERNEL);
 			if (!g)
 				break;
 
-			g->sg_size = ((ROUNDUP4(OCTNIC_MAX_SG) >> 2) *
-				      OCT_SG_ENTRY_SIZE);
+			g->sg = lio->glists_virt_base[i] +
+				(j * lio->glist_entry_size);
 
-			g->sg = kmalloc(g->sg_size + 8, GFP_KERNEL);
-			if (!g->sg) {
-				kfree(g);
-				break;
-			}
+			g->sg_dma_ptr = lio->glists_dma_base[i] +
+					(j * lio->glist_entry_size);
 
-			/* The gather component should be aligned on 64-bit
-			 * boundary
-			 */
-			if (((unsigned long)g->sg) & 7) {
-				g->adjust = 8 - (((unsigned long)g->sg) & 7);
-				g->sg = (struct octeon_sg_entry *)
-					((unsigned long)g->sg + g->adjust);
-			}
 			list_add_tail(&g->list, &lio->glist[i]);
 		}
 
 		if (j != lio->tx_qsize) {
 			delete_glists(lio);
-			return 1;
+			return -ENOMEM;
 		}
 	}
 
@@ -1324,10 +1354,6 @@ static void free_netsgbuf(void *buf)
 		i++;
 	}
 
-	dma_unmap_single(&lio->oct_dev->pci_dev->dev,
-			 finfo->dptr, g->sg_size,
-			 DMA_TO_DEVICE);
-
 	iq = skb_iq(lio, skb);
 
 	spin_lock(&lio->glist_lock[iq]);
@@ -1374,10 +1400,6 @@ static void free_netsgbuf_with_resp(void *buf)
 		i++;
 	}
 
-	dma_unmap_single(&lio->oct_dev->pci_dev->dev,
-			 finfo->dptr, g->sg_size,
-			 DMA_TO_DEVICE);
-
 	iq = skb_iq(lio, skb);
 
 	spin_lock(&lio->glist_lock[iq]);
@@ -2382,23 +2404,7 @@ static int liquidio_xmit(struct sk_buff *skb, struct net_device *netdev)
 			i++;
 		}
 
-		dptr = dma_map_single(&oct->pci_dev->dev,
-				      g->sg, g->sg_size,
-				      DMA_TO_DEVICE);
-		if (dma_mapping_error(&oct->pci_dev->dev, dptr)) {
-			dev_err(&oct->pci_dev->dev, "%s DMA mapping error 4\n",
-				__func__);
-			dma_unmap_single(&oct->pci_dev->dev, g->sg[0].ptr[0],
-					 skb->len - skb->data_len,
-					 DMA_TO_DEVICE);
-			for (j = 1; j <= frags; j++) {
-				frag = &skb_shinfo(skb)->frags[j - 1];
-				dma_unmap_page(&oct->pci_dev->dev,
-					       g->sg[j >> 2].ptr[j & 3],
-					       frag->size, DMA_TO_DEVICE);
-			}
-			return NETDEV_TX_BUSY;
-		}
+		dptr = g->sg_dma_ptr;
 
 		ndata.cmd.cmd3.dptr = dptr;
 		finfo->dptr = dptr;
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_config.h b/drivers/net/ethernet/cavium/liquidio/octeon_config.h
index b3dc2e9..d29ebc5 100644
--- a/drivers/net/ethernet/cavium/liquidio/octeon_config.h
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_config.h
@@ -71,17 +71,17 @@
 #define   CN23XX_MAX_RINGS_PER_VF          8
 
 #define   CN23XX_MAX_INPUT_QUEUES	CN23XX_MAX_RINGS_PER_PF
-#define   CN23XX_MAX_IQ_DESCRIPTORS	2048
+#define   CN23XX_MAX_IQ_DESCRIPTORS	512
 #define   CN23XX_DB_MIN                 1
 #define   CN23XX_DB_MAX                 8
 #define   CN23XX_DB_TIMEOUT             1
 
 #define   CN23XX_MAX_OUTPUT_QUEUES	CN23XX_MAX_RINGS_PER_PF
-#define   CN23XX_MAX_OQ_DESCRIPTORS	2048
+#define   CN23XX_MAX_OQ_DESCRIPTORS	512
 #define   CN23XX_OQ_BUF_SIZE		1536
 #define   CN23XX_OQ_PKTSPER_INTR	128
 /*#define CAVIUM_ONLY_CN23XX_RX_PERF*/
-#define   CN23XX_OQ_REFIL_THRESHOLD	128
+#define   CN23XX_OQ_REFIL_THRESHOLD	16
 
 #define   CN23XX_OQ_INTR_PKT		64
 #define   CN23XX_OQ_INTR_TIME		100
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_droq.c b/drivers/net/ethernet/cavium/liquidio/octeon_droq.c
index 0be87d1..79f8094 100644
--- a/drivers/net/ethernet/cavium/liquidio/octeon_droq.c
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_droq.c
@@ -155,11 +155,6 @@ octeon_droq_destroy_ring_buffers(struct octeon_device *oct,
 			recv_buffer_destroy(droq->recv_buf_list[i].buffer,
 					    pg_info);
 
-		if (droq->desc_ring && droq->desc_ring[i].info_ptr)
-			lio_unmap_ring_info(oct->pci_dev,
-					    (u64)droq->
-					    desc_ring[i].info_ptr,
-					    OCT_DROQ_INFO_SIZE);
 		droq->recv_buf_list[i].buffer = NULL;
 	}
 
@@ -211,10 +206,7 @@ int octeon_delete_droq(struct octeon_device *oct, u32 q_no)
 	vfree(droq->recv_buf_list);
 
 	if (droq->info_base_addr)
-		cnnic_free_aligned_dma(oct->pci_dev, droq->info_list,
-				       droq->info_alloc_size,
-				       droq->info_base_addr,
-				       droq->info_list_dma);
+		lio_free_info_buffer(oct, droq);
 
 	if (droq->desc_ring)
 		lio_dma_free(oct, (droq->max_count * OCT_DROQ_DESC_SIZE),
@@ -294,12 +286,7 @@ int octeon_init_droq(struct octeon_device *oct,
 	dev_dbg(&oct->pci_dev->dev, "droq[%d]: num_desc: %d\n", q_no,
 		droq->max_count);
 
-	droq->info_list =
-		cnnic_numa_alloc_aligned_dma((droq->max_count *
-					      OCT_DROQ_INFO_SIZE),
-					     &droq->info_alloc_size,
-					     &droq->info_base_addr,
-					     numa_node);
+	droq->info_list = lio_alloc_info_buffer(oct, droq);
 	if (!droq->info_list) {
 		dev_err(&oct->pci_dev->dev, "Cannot allocate memory for info list.\n");
 		lio_dma_free(oct, (droq->max_count * OCT_DROQ_DESC_SIZE),
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_droq.h b/drivers/net/ethernet/cavium/liquidio/octeon_droq.h
index e620740..6982c0a 100644
--- a/drivers/net/ethernet/cavium/liquidio/octeon_droq.h
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_droq.h
@@ -325,10 +325,10 @@ struct octeon_droq {
 	size_t desc_ring_dma;
 
 	/** Info ptr list are allocated at this virtual address. */
-	size_t info_base_addr;
+	void *info_base_addr;
 
 	/** DMA mapped address of the info list */
-	size_t info_list_dma;
+	dma_addr_t info_list_dma;
 
 	/** Allocated size of info list. */
 	u32 info_alloc_size;
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_main.h b/drivers/net/ethernet/cavium/liquidio/octeon_main.h
index 8cd3891..b3183c9 100644
--- a/drivers/net/ethernet/cavium/liquidio/octeon_main.h
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_main.h
@@ -138,48 +138,6 @@ static inline int octeon_map_pci_barx(struct octeon_device *oct,
 	return 1;
 }
 
-static inline void *
-cnnic_numa_alloc_aligned_dma(u32 size,
-			     u32 *alloc_size,
-			     size_t *orig_ptr,
-			     int numa_node)
-{
-	int retries = 0;
-	void *ptr = NULL;
-
-#define OCTEON_MAX_ALLOC_RETRIES     1
-	do {
-		struct page *page = NULL;
-
-		page = alloc_pages_node(numa_node,
-					GFP_KERNEL,
-					get_order(size));
-		if (!page)
-			page = alloc_pages(GFP_KERNEL,
-					   get_order(size));
-		ptr = (void *)page_address(page);
-		if ((unsigned long)ptr & 0x07) {
-			__free_pages(page, get_order(size));
-			ptr = NULL;
-			/* Increment the size required if the first
-			 * attempt failed.
-			 */
-			if (!retries)
-				size += 7;
-		}
-		retries++;
-	} while ((retries <= OCTEON_MAX_ALLOC_RETRIES) && !ptr);
-
-	*alloc_size = size;
-	*orig_ptr = (unsigned long)ptr;
-	if ((unsigned long)ptr & 0x07)
-		ptr = (void *)(((unsigned long)ptr + 7) & ~(7UL));
-	return ptr;
-}
-
-#define cnnic_free_aligned_dma(pci_dev, ptr, size, orig_ptr, dma_addr) \
-		free_pages(orig_ptr, get_order(size))
-
 static inline int
 sleep_cond(wait_queue_head_t *wait_queue, int *condition)
 {
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_network.h b/drivers/net/ethernet/cavium/liquidio/octeon_network.h
index 6bb8941..eef2a1e 100644
--- a/drivers/net/ethernet/cavium/liquidio/octeon_network.h
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_network.h
@@ -62,6 +62,9 @@ struct lio {
 
 	/** Array of gather component linked lists */
 	struct list_head *glist;
+	void **glists_virt_base;
+	dma_addr_t *glists_dma_base;
+	u32 glist_entry_size;
 
 	/** Pointer to the NIC properties for the Octeon device this network
 	 *  interface is associated with.
@@ -344,6 +347,29 @@ static inline void tx_buffer_free(void *buffer)
 #define lio_dma_free(oct, size, virt_addr, dma_addr) \
 	dma_free_coherent(&(oct)->pci_dev->dev, size, virt_addr, dma_addr)
 
+static inline void *
+lio_alloc_info_buffer(struct octeon_device *oct,
+		      struct octeon_droq *droq)
+{
+	void *virt_ptr;
+
+	virt_ptr = lio_dma_alloc(oct, (droq->max_count * OCT_DROQ_INFO_SIZE),
+				 &droq->info_list_dma);
+	if (virt_ptr) {
+		droq->info_alloc_size = droq->max_count * OCT_DROQ_INFO_SIZE;
+		droq->info_base_addr = virt_ptr;
+	}
+
+	return virt_ptr;
+}
+
+static inline void lio_free_info_buffer(struct octeon_device *oct,
+					struct octeon_droq *droq)
+{
+	lio_dma_free(oct, droq->info_alloc_size, droq->info_base_addr,
+		     droq->info_list_dma);
+}
+
 static inline
 void *get_rbd(struct sk_buff *skb)
 {
@@ -359,22 +385,7 @@ void *get_rbd(struct sk_buff *skb)
 static inline u64
 lio_map_ring_info(struct octeon_droq *droq, u32 i)
 {
-	dma_addr_t dma_addr;
-	struct octeon_device *oct = droq->oct_dev;
-
-	dma_addr = dma_map_single(&oct->pci_dev->dev, &droq->info_list[i],
-				  OCT_DROQ_INFO_SIZE, DMA_FROM_DEVICE);
-
-	WARN_ON(dma_mapping_error(&oct->pci_dev->dev, dma_addr));
-
-	return (u64)dma_addr;
-}
-
-static inline void
-lio_unmap_ring_info(struct pci_dev *pci_dev,
-		    u64 info_ptr, u32 size)
-{
-	dma_unmap_single(&pci_dev->dev, info_ptr, size, DMA_FROM_DEVICE);
+	return droq->info_list_dma + (i * sizeof(struct octeon_droq_info));
 }
 
 static inline u64