From: Shannon Nelson <snelson@pensando.io>
Date: Tue, 1 Sep 2020 11:20:19 -0700
Subject: ionic: clean up page handling code
Patch-mainline: v5.10-rc1
Git-commit: 63cd9083b171cf78d56a9642c7a04272876123f5
References: jsc#SLE-16649

The internal page handling can be cleaned up by passing our
local page struct rather than dma addresses, and by putting
more of the mgmt code into the alloc and free routines.

Co-developed-by: Neel Patel <neel@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/pensando/ionic/ionic_txrx.c |   71 ++++++++++++-----------
 1 file changed, 40 insertions(+), 31 deletions(-)

--- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c
@@ -266,40 +266,49 @@ void ionic_rx_flush(struct ionic_cq *cq)
 				   work_done, IONIC_INTR_CRED_RESET_COALESCE);
 }
 
-static struct page *ionic_rx_page_alloc(struct ionic_queue *q,
-					dma_addr_t *dma_addr)
+static int ionic_rx_page_alloc(struct ionic_queue *q,
+			       struct ionic_page_info *page_info)
 {
 	struct ionic_lif *lif = q->lif;
 	struct ionic_rx_stats *stats;
 	struct net_device *netdev;
 	struct device *dev;
-	struct page *page;
 
 	netdev = lif->netdev;
 	dev = lif->ionic->dev;
 	stats = q_to_rx_stats(q);
-	page = alloc_page(GFP_ATOMIC);
-	if (unlikely(!page)) {
-		net_err_ratelimited("%s: Page alloc failed on %s!\n",
+
+	if (unlikely(!page_info)) {
+		net_err_ratelimited("%s: %s invalid page_info in alloc\n",
+				    netdev->name, q->name);
+		return -EINVAL;
+	}
+
+	page_info->page = dev_alloc_page();
+	if (unlikely(!page_info->page)) {
+		net_err_ratelimited("%s: %s page alloc failed\n",
 				    netdev->name, q->name);
 		stats->alloc_err++;
-		return NULL;
+		return -ENOMEM;
 	}
 
-	*dma_addr = dma_map_page(dev, page, 0, PAGE_SIZE, DMA_FROM_DEVICE);
-	if (unlikely(dma_mapping_error(dev, *dma_addr))) {
-		__free_page(page);
-		net_err_ratelimited("%s: DMA single map failed on %s!\n",
+	page_info->dma_addr = dma_map_page(dev, page_info->page, 0, PAGE_SIZE,
+					   DMA_FROM_DEVICE);
+	if (unlikely(dma_mapping_error(dev, page_info->dma_addr))) {
+		put_page(page_info->page);
+		page_info->dma_addr = 0;
+		page_info->page = NULL;
+		net_err_ratelimited("%s: %s dma map failed\n",
 				    netdev->name, q->name);
 		stats->dma_map_err++;
-		return NULL;
+		return -EIO;
 	}
 
-	return page;
+	return 0;
 }
 
-static void ionic_rx_page_free(struct ionic_queue *q, struct page *page,
-			       dma_addr_t dma_addr)
+static void ionic_rx_page_free(struct ionic_queue *q,
+			       struct ionic_page_info *page_info)
 {
 	struct ionic_lif *lif = q->lif;
 	struct net_device *netdev;
@@ -308,15 +317,23 @@ static void ionic_rx_page_free(struct io
 	netdev = lif->netdev;
 	dev = lif->ionic->dev;
 
-	if (unlikely(!page)) {
-		net_err_ratelimited("%s: Trying to free unallocated buffer on %s!\n",
+	if (unlikely(!page_info)) {
+		net_err_ratelimited("%s: %s invalid page_info in free\n",
+				    netdev->name, q->name);
+		return;
+	}
+
+	if (unlikely(!page_info->page)) {
+		net_err_ratelimited("%s: %s invalid page in free\n",
 				    netdev->name, q->name);
 		return;
 	}
 
-	dma_unmap_page(dev, dma_addr, PAGE_SIZE, DMA_FROM_DEVICE);
+	dma_unmap_page(dev, page_info->dma_addr, PAGE_SIZE, DMA_FROM_DEVICE);
 
-	__free_page(page);
+	put_page(page_info->page);
+	page_info->dma_addr = 0;
+	page_info->page = NULL;
 }
 
 void ionic_rx_fill(struct ionic_queue *q)
@@ -352,8 +369,7 @@ void ionic_rx_fill(struct ionic_queue *q
 		desc->opcode = (nfrags > 1) ? IONIC_RXQ_DESC_OPCODE_SG :
 					      IONIC_RXQ_DESC_OPCODE_SIMPLE;
 		desc_info->npages = nfrags;
-		page_info->page = ionic_rx_page_alloc(q, &page_info->dma_addr);
-		if (unlikely(!page_info->page)) {
+		if (unlikely(ionic_rx_page_alloc(q, page_info))) {
 			desc->addr = 0;
 			desc->len = 0;
 			return;
@@ -370,8 +386,7 @@ void ionic_rx_fill(struct ionic_queue *q
 				continue;
 
 			sg_elem = &sg_desc->elems[j];
-			page_info->page = ionic_rx_page_alloc(q, &page_info->dma_addr);
-			if (unlikely(!page_info->page)) {
+			if (unlikely(ionic_rx_page_alloc(q, page_info))) {
 				sg_elem->addr = 0;
 				sg_elem->len = 0;
 				return;
@@ -409,14 +424,8 @@ void ionic_rx_empty(struct ionic_queue *
 		desc->addr = 0;
 		desc->len = 0;
 
-		for (i = 0; i < desc_info->npages; i++) {
-			if (likely(desc_info->pages[i].page)) {
-				ionic_rx_page_free(q, desc_info->pages[i].page,
-						   desc_info->pages[i].dma_addr);
-				desc_info->pages[i].page = NULL;
-				desc_info->pages[i].dma_addr = 0;
-			}
-		}
+		for (i = 0; i < desc_info->npages; i++)
+			ionic_rx_page_free(q, &desc_info->pages[i]);
 
 		desc_info->cb_arg = NULL;
 		idx = (idx + 1) & (q->num_descs - 1);