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From:   laurentiu.tudor@nxp.com
To:     netdev@vger.kernel.org, madalin.bucur@nxp.com, roy.pledge@nxp.com,
        camelia.groza@nxp.com, leoyang.li@nxp.com
Cc:     davem@davemloft.net, iommu@lists.linux-foundation.org,
        linux-arm-kernel@lists.infradead.org,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        Laurentiu Tudor <laurentiu.tudor@nxp.com>
Subject: [PATCH 12/13] dpaa_eth: fix iova handling for sg frames
Date:   Fri, 29 Mar 2019 16:00:13 +0200
Message-Id: <20190329140014.8126-13-laurentiu.tudor@nxp.com>
In-Reply-To: <20190329140014.8126-1-laurentiu.tudor@nxp.com>
References: <20190329140014.8126-1-laurentiu.tudor@nxp.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Laurentiu Tudor <laurentiu.tudor@nxp.com>

The driver relies on the no longer valid assumption that dma addresses
(iovas) are identical to physical addressees and uses phys_to_virt() to
make iova -> vaddr conversions. Fix this also for scatter-gather frames
using the iova -> phys conversion function added in the previous patch.
While at it, clean-up a redundant dpaa_bpid2pool() and pass the bp
as parameter.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Acked-by: Madalin Bucur <madalin.bucur@nxp.com>
---
 .../net/ethernet/freescale/dpaa/dpaa_eth.c    | 41 +++++++++++--------
 1 file changed, 24 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
index f17edc80dc37..daede7272768 100644
--- a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
+++ b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
@@ -1646,14 +1646,17 @@ static struct sk_buff *dpaa_cleanup_tx_fd(const struct dpaa_priv *priv,
 
 	if (unlikely(qm_fd_get_format(fd) == qm_fd_sg)) {
 		nr_frags = skb_shinfo(skb)->nr_frags;
-		dma_unmap_single(dev, addr,
-				 qm_fd_get_offset(fd) + DPAA_SGT_SIZE,
-				 dma_dir);
 
 		/* The sgt buffer has been allocated with netdev_alloc_frag(),
 		 * it's from lowmem.
 		 */
-		sgt = phys_to_virt(addr + qm_fd_get_offset(fd));
+		sgt = phys_to_virt(dpaa_iova_to_phys(dev,
+						     addr +
+						     qm_fd_get_offset(fd)));
+
+		dma_unmap_single(dev, addr,
+				 qm_fd_get_offset(fd) + DPAA_SGT_SIZE,
+				 dma_dir);
 
 		/* sgt[0] is from lowmem, was dma_map_single()-ed */
 		dma_unmap_single(dev, qm_sg_addr(&sgt[0]),
@@ -1668,7 +1671,7 @@ static struct sk_buff *dpaa_cleanup_tx_fd(const struct dpaa_priv *priv,
 		}
 
 		/* Free the page frag that we allocated on Tx */
-		skb_free_frag(phys_to_virt(addr));
+		skb_free_frag(skbh);
 	} else {
 		dma_unmap_single(dev, addr,
 				 skb_tail_pointer(skb) - (u8 *)skbh, dma_dir);
@@ -1729,14 +1732,14 @@ static struct sk_buff *contig_fd_to_skb(const struct dpaa_priv *priv,
  * The page fragment holding the S/G Table is recycled here.
  */
 static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
-				    const struct qm_fd *fd)
+				    const struct qm_fd *fd,
+				    struct dpaa_bp *dpaa_bp,
+				    void *vaddr)
 {
 	ssize_t fd_off = qm_fd_get_offset(fd);
-	dma_addr_t addr = qm_fd_addr(fd);
 	const struct qm_sg_entry *sgt;
 	struct page *page, *head_page;
-	struct dpaa_bp *dpaa_bp;
-	void *vaddr, *sg_vaddr;
+	void *sg_vaddr;
 	int frag_off, frag_len;
 	struct sk_buff *skb;
 	dma_addr_t sg_addr;
@@ -1745,7 +1748,6 @@ static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
 	int *count_ptr;
 	int i;
 
-	vaddr = phys_to_virt(addr);
 	WARN_ON(!IS_ALIGNED((unsigned long)vaddr, SMP_CACHE_BYTES));
 
 	/* Iterate through the SGT entries and add data buffers to the skb */
@@ -1756,14 +1758,18 @@ static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
 		WARN_ON(qm_sg_entry_is_ext(&sgt[i]));
 
 		sg_addr = qm_sg_addr(&sgt[i]);
-		sg_vaddr = phys_to_virt(sg_addr);
-		WARN_ON(!IS_ALIGNED((unsigned long)sg_vaddr,
-				    SMP_CACHE_BYTES));
 
 		/* We may use multiple Rx pools */
 		dpaa_bp = dpaa_bpid2pool(sgt[i].bpid);
-		if (!dpaa_bp)
+		if (!dpaa_bp) {
+			pr_info("%s: fail to get dpaa_bp for sg bpid %d\n",
+				__func__, sgt[i].bpid);
 			goto free_buffers;
+		}
+		sg_vaddr = phys_to_virt(dpaa_iova_to_phys(dpaa_bp->dev,
+							  sg_addr));
+		WARN_ON(!IS_ALIGNED((unsigned long)sg_vaddr,
+				    SMP_CACHE_BYTES));
 
 		count_ptr = this_cpu_ptr(dpaa_bp->percpu_count);
 		dma_unmap_single(dpaa_bp->dev, sg_addr, dpaa_bp->size,
@@ -1835,10 +1841,11 @@ static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
 	/* free all the SG entries */
 	for (i = 0; i < DPAA_SGT_MAX_ENTRIES ; i++) {
 		sg_addr = qm_sg_addr(&sgt[i]);
-		sg_vaddr = phys_to_virt(sg_addr);
-		skb_free_frag(sg_vaddr);
 		dpaa_bp = dpaa_bpid2pool(sgt[i].bpid);
 		if (dpaa_bp) {
+			sg_addr = dpaa_iova_to_phys(dpaa_bp->dev, sg_addr);
+			sg_vaddr = phys_to_virt(sg_addr);
+			skb_free_frag(sg_vaddr);
 			count_ptr = this_cpu_ptr(dpaa_bp->percpu_count);
 			(*count_ptr)--;
 		}
@@ -2331,7 +2338,7 @@ static enum qman_cb_dqrr_result rx_default_dqrr(struct qman_portal *portal,
 	if (likely(fd_format == qm_fd_contig))
 		skb = contig_fd_to_skb(priv, fd, dpaa_bp, vaddr);
 	else
-		skb = sg_fd_to_skb(priv, fd);
+		skb = sg_fd_to_skb(priv, fd, dpaa_bp, vaddr);
 	if (!skb)
 		return qman_cb_dqrr_consume;
 
-- 
2.17.1