5.4-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Fourier fourier.thomas@gmail.com
[ Upstream commit 561aa0e22b70a5e7246b73d62a824b3aef3fc375 ]
dma_map_XXX() functions return values DMA_MAPPING_ERROR as error values which is often ~0. The error value should be tested with dma_mapping_error().
This patch creates a new function in niu_ops to test if the mapping failed. The test is fixed in niu_rbr_add_page(), added in niu_start_xmit() and the successfully mapped pages are unmaped upon error.
Fixes: ec2deec1f352 ("niu: Fix to check for dma mapping errors.") Signed-off-by: Thomas Fourier fourier.thomas@gmail.com Reviewed-by: Simon Horman horms@kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/sun/niu.c | 31 ++++++++++++++++++++++++++++++- drivers/net/ethernet/sun/niu.h | 4 ++++ 2 files changed, 34 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c index e659415c62bd7..ca991bcb2e512 100644 --- a/drivers/net/ethernet/sun/niu.c +++ b/drivers/net/ethernet/sun/niu.c @@ -3317,7 +3317,7 @@ static int niu_rbr_add_page(struct niu *np, struct rx_ring_info *rp,
addr = np->ops->map_page(np->device, page, 0, PAGE_SIZE, DMA_FROM_DEVICE); - if (!addr) { + if (np->ops->mapping_error(np->device, addr)) { __free_page(page); return -ENOMEM; } @@ -6654,6 +6654,8 @@ static netdev_tx_t niu_start_xmit(struct sk_buff *skb, len = skb_headlen(skb); mapping = np->ops->map_single(np->device, skb->data, len, DMA_TO_DEVICE); + if (np->ops->mapping_error(np->device, mapping)) + goto out_drop;
prod = rp->prod;
@@ -6695,6 +6697,8 @@ static netdev_tx_t niu_start_xmit(struct sk_buff *skb, mapping = np->ops->map_page(np->device, skb_frag_page(frag), skb_frag_off(frag), len, DMA_TO_DEVICE); + if (np->ops->mapping_error(np->device, mapping)) + goto out_unmap;
rp->tx_buffs[prod].skb = NULL; rp->tx_buffs[prod].mapping = mapping; @@ -6719,6 +6723,19 @@ static netdev_tx_t niu_start_xmit(struct sk_buff *skb, out: return NETDEV_TX_OK;
+out_unmap: + while (i--) { + const skb_frag_t *frag; + + prod = PREVIOUS_TX(rp, prod); + frag = &skb_shinfo(skb)->frags[i]; + np->ops->unmap_page(np->device, rp->tx_buffs[prod].mapping, + skb_frag_size(frag), DMA_TO_DEVICE); + } + + np->ops->unmap_single(np->device, rp->tx_buffs[rp->prod].mapping, + skb_headlen(skb), DMA_TO_DEVICE); + out_drop: rp->tx_errors++; kfree_skb(skb); @@ -9612,6 +9629,11 @@ static void niu_pci_unmap_single(struct device *dev, u64 dma_address, dma_unmap_single(dev, dma_address, size, direction); }
+static int niu_pci_mapping_error(struct device *dev, u64 addr) +{ + return dma_mapping_error(dev, addr); +} + static const struct niu_ops niu_pci_ops = { .alloc_coherent = niu_pci_alloc_coherent, .free_coherent = niu_pci_free_coherent, @@ -9619,6 +9641,7 @@ static const struct niu_ops niu_pci_ops = { .unmap_page = niu_pci_unmap_page, .map_single = niu_pci_map_single, .unmap_single = niu_pci_unmap_single, + .mapping_error = niu_pci_mapping_error, };
static void niu_driver_version(void) @@ -9996,6 +10019,11 @@ static void niu_phys_unmap_single(struct device *dev, u64 dma_address, /* Nothing to do. */ }
+static int niu_phys_mapping_error(struct device *dev, u64 dma_address) +{ + return false; +} + static const struct niu_ops niu_phys_ops = { .alloc_coherent = niu_phys_alloc_coherent, .free_coherent = niu_phys_free_coherent, @@ -10003,6 +10031,7 @@ static const struct niu_ops niu_phys_ops = { .unmap_page = niu_phys_unmap_page, .map_single = niu_phys_map_single, .unmap_single = niu_phys_unmap_single, + .mapping_error = niu_phys_mapping_error, };
static int niu_of_probe(struct platform_device *op) diff --git a/drivers/net/ethernet/sun/niu.h b/drivers/net/ethernet/sun/niu.h index 04c215f91fc08..0b169c08b0f2d 100644 --- a/drivers/net/ethernet/sun/niu.h +++ b/drivers/net/ethernet/sun/niu.h @@ -2879,6 +2879,9 @@ struct tx_ring_info { #define NEXT_TX(tp, index) \ (((index) + 1) < (tp)->pending ? ((index) + 1) : 0)
+#define PREVIOUS_TX(tp, index) \ + (((index) - 1) >= 0 ? ((index) - 1) : (((tp)->pending) - 1)) + static inline u32 niu_tx_avail(struct tx_ring_info *tp) { return (tp->pending - @@ -3140,6 +3143,7 @@ struct niu_ops { enum dma_data_direction direction); void (*unmap_single)(struct device *dev, u64 dma_address, size_t size, enum dma_data_direction direction); + int (*mapping_error)(struct device *dev, u64 dma_address); };
struct niu_link_config {