6.12-stable review patch. If anyone has any objections, please let me know.
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From: Jijie Shao shaojijie@huawei.com
[ Upstream commit 49ade8630f36e9dca2395592cfb0b7deeb07e746 ]
The SMMU engine on HIP09 chip has a hardware issue. SMMU pagetable prefetch features may prefetch and use a invalid PTE even the PTE is valid at that time. This will cause the device trigger fake pagefaults. The solution is to avoid prefetching by adding a SYNC command when smmu mapping a iova. But the performance of nic has a sharp drop. Then we do this workaround, always enable tx bounce buffer, avoid mapping/unmapping on TX path.
This issue only affects HNS3, so we always enable tx bounce buffer when smmu enabled to improve performance.
Fixes: 295ba232a8c3 ("net: hns3: add device version to replace pci revision") Signed-off-by: Jian Shen shenjian15@huawei.com Signed-off-by: Jijie Shao shaojijie@huawei.com Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20250722125423.1270673-5-shaojijie@huawei.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/hisilicon/hns3/hns3_enet.c | 31 +++++++++++++++++++ .../net/ethernet/hisilicon/hns3/hns3_enet.h | 2 ++ 2 files changed, 33 insertions(+)
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c index 24062a40a7793..94432e237640d 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -11,6 +11,7 @@ #include <linux/irq.h> #include <linux/ip.h> #include <linux/ipv6.h> +#include <linux/iommu.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/skbuff.h> @@ -1039,6 +1040,8 @@ static bool hns3_can_use_tx_sgl(struct hns3_enet_ring *ring, static void hns3_init_tx_spare_buffer(struct hns3_enet_ring *ring) { u32 alloc_size = ring->tqp->handle->kinfo.tx_spare_buf_size; + struct net_device *netdev = ring_to_netdev(ring); + struct hns3_nic_priv *priv = netdev_priv(netdev); struct hns3_tx_spare *tx_spare; struct page *page; dma_addr_t dma; @@ -1080,6 +1083,7 @@ static void hns3_init_tx_spare_buffer(struct hns3_enet_ring *ring) tx_spare->buf = page_address(page); tx_spare->len = PAGE_SIZE << order; ring->tx_spare = tx_spare; + ring->tx_copybreak = priv->tx_copybreak; return;
dma_mapping_error: @@ -4874,6 +4878,30 @@ static void hns3_nic_dealloc_vector_data(struct hns3_nic_priv *priv) devm_kfree(&pdev->dev, priv->tqp_vector); }
+static void hns3_update_tx_spare_buf_config(struct hns3_nic_priv *priv) +{ +#define HNS3_MIN_SPARE_BUF_SIZE (2 * 1024 * 1024) +#define HNS3_MAX_PACKET_SIZE (64 * 1024) + + struct iommu_domain *domain = iommu_get_domain_for_dev(priv->dev); + struct hnae3_ae_dev *ae_dev = hns3_get_ae_dev(priv->ae_handle); + struct hnae3_handle *handle = priv->ae_handle; + + if (ae_dev->dev_version < HNAE3_DEVICE_VERSION_V3) + return; + + if (!(domain && iommu_is_dma_domain(domain))) + return; + + priv->min_tx_copybreak = HNS3_MAX_PACKET_SIZE; + priv->min_tx_spare_buf_size = HNS3_MIN_SPARE_BUF_SIZE; + + if (priv->tx_copybreak < priv->min_tx_copybreak) + priv->tx_copybreak = priv->min_tx_copybreak; + if (handle->kinfo.tx_spare_buf_size < priv->min_tx_spare_buf_size) + handle->kinfo.tx_spare_buf_size = priv->min_tx_spare_buf_size; +} + static void hns3_ring_get_cfg(struct hnae3_queue *q, struct hns3_nic_priv *priv, unsigned int ring_type) { @@ -5107,6 +5135,7 @@ int hns3_init_all_ring(struct hns3_nic_priv *priv) int i, j; int ret;
+ hns3_update_tx_spare_buf_config(priv); for (i = 0; i < ring_num; i++) { ret = hns3_alloc_ring_memory(&priv->ring[i]); if (ret) { @@ -5311,6 +5340,8 @@ static int hns3_client_init(struct hnae3_handle *handle) priv->ae_handle = handle; priv->tx_timeout_count = 0; priv->max_non_tso_bd_num = ae_dev->dev_specs.max_non_tso_bd_num; + priv->min_tx_copybreak = 0; + priv->min_tx_spare_buf_size = 0; set_bit(HNS3_NIC_STATE_DOWN, &priv->state);
handle->msg_enable = netif_msg_init(debug, DEFAULT_MSG_LEVEL); diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h index d36c4ed16d8dd..caf7a4df85852 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h @@ -596,6 +596,8 @@ struct hns3_nic_priv { struct hns3_enet_coalesce rx_coal; u32 tx_copybreak; u32 rx_copybreak; + u32 min_tx_copybreak; + u32 min_tx_spare_buf_size; };
union l3_hdr_info {