net/mlx5e: Fix usage of DMA sync API

DMA sync functions should use the same direction that was used by DMA
mapping. Use DMA_BIDIRECTIONAL for XDP_TX from regular RQ, which reuses
the same mapping that was used for RX, and DMA_TO_DEVICE for XDP_TX from
XSK RQ and XDP_REDIRECT, which establish a new mapping in this
direction. On the RX side, use the same direction that was used when
setting up the mapping (DMA_BIDIRECTIONAL for XDP, DMA_FROM_DEVICE
otherwise).

Also don't skip sync for device when establishing a DMA_FROM_DEVICE
mapping for RX, as some architectures (ARM) may require invalidating
caches before the device can use the mapping. It doesn't break the
bugfix made in
commit 0b7cfa4082fb ("net/mlx5e: Fix page DMA map/unmap attributes"),
since the bug happened on unmap.

Fixes: 0b7cfa4082fb ("net/mlx5e: Fix page DMA map/unmap attributes")
Fixes: b5503b994ed5 ("net/mlx5e: XDP TX forwarding support")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
index 4685c65..20507ef 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
@@ -117,7 +117,7 @@ mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq,
        xdpi.page.rq = rq;
 
        dma_addr = page_pool_get_dma_addr(page) + (xdpf->data - (void *)xdpf);
-       dma_sync_single_for_device(sq->pdev, dma_addr, xdptxd.len, DMA_TO_DEVICE);
+       dma_sync_single_for_device(sq->pdev, dma_addr, xdptxd.len, DMA_BIDIRECTIONAL);
 
        if (unlikely(xdp_frame_has_frags(xdpf))) {
                sinfo = xdp_get_shared_info_from_frame(xdpf);
@@ -131,7 +131,7 @@ mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq,
                                skb_frag_off(frag);
                        len = skb_frag_size(frag);
                        dma_sync_single_for_device(sq->pdev, addr, len,
-                                                  DMA_TO_DEVICE);
+                                                  DMA_BIDIRECTIONAL);
                }
        }
 

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 5808465..a61a43f 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -266,7 +266,7 @@ static inline bool mlx5e_rx_cache_get(struct mlx5e_rq *rq, union mlx5e_alloc_uni
 
        addr = page_pool_get_dma_addr(au->page);
        /* Non-XSK always uses PAGE_SIZE. */
-       dma_sync_single_for_device(rq->pdev, addr, PAGE_SIZE, DMA_FROM_DEVICE);
+       dma_sync_single_for_device(rq->pdev, addr, PAGE_SIZE, rq->buff.map_dir);
        return true;
 }
 
@@ -282,8 +282,7 @@ static inline int mlx5e_page_alloc_pool(struct mlx5e_rq *rq, union mlx5e_alloc_u
                return -ENOMEM;
 
        /* Non-XSK always uses PAGE_SIZE. */
-       addr = dma_map_page_attrs(rq->pdev, au->page, 0, PAGE_SIZE,
-                                 rq->buff.map_dir, DMA_ATTR_SKIP_CPU_SYNC);
+       addr = dma_map_page(rq->pdev, au->page, 0, PAGE_SIZE, rq->buff.map_dir);
        if (unlikely(dma_mapping_error(rq->pdev, addr))) {
                page_pool_recycle_direct(rq->page_pool, au->page);
                au->page = NULL;
@@ -427,14 +426,15 @@ mlx5e_add_skb_frag(struct mlx5e_rq *rq, struct sk_buff *skb,
 {
        dma_addr_t addr = page_pool_get_dma_addr(au->page);
 
-       dma_sync_single_for_cpu(rq->pdev, addr + frag_offset, len, DMA_FROM_DEVICE);
+       dma_sync_single_for_cpu(rq->pdev, addr + frag_offset, len,
+                               rq->buff.map_dir);
        page_ref_inc(au->page);
        skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
                        au->page, frag_offset, len, truesize);
 }
 
 static inline void
-mlx5e_copy_skb_header(struct device *pdev, struct sk_buff *skb,
+mlx5e_copy_skb_header(struct mlx5e_rq *rq, struct sk_buff *skb,
                      struct page *page, dma_addr_t addr,
                      int offset_from, int dma_offset, u32 headlen)
 {
@@ -442,7 +442,8 @@ mlx5e_copy_skb_header(struct device *pdev, struct sk_buff *skb,
        /* Aligning len to sizeof(long) optimizes memcpy performance */
        unsigned int len = ALIGN(headlen, sizeof(long));
 
-       dma_sync_single_for_cpu(pdev, addr + dma_offset, len, DMA_FROM_DEVICE);
+       dma_sync_single_for_cpu(rq->pdev, addr + dma_offset, len,
+                               rq->buff.map_dir);
        skb_copy_to_linear_data(skb, from, len);
 }
 
@@ -1538,7 +1539,7 @@ mlx5e_skb_from_cqe_linear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi,
 
        addr = page_pool_get_dma_addr(au->page);
        dma_sync_single_range_for_cpu(rq->pdev, addr, wi->offset,
-                                     frag_size, DMA_FROM_DEVICE);
+                                     frag_size, rq->buff.map_dir);
        net_prefetch(data);
 
        prog = rcu_dereference(rq->xdp_prog);
@@ -1587,7 +1588,7 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 
        addr = page_pool_get_dma_addr(au->page);
        dma_sync_single_range_for_cpu(rq->pdev, addr, wi->offset,
-                                     rq->buff.frame0_sz, DMA_FROM_DEVICE);
+                                     rq->buff.frame0_sz, rq->buff.map_dir);
        net_prefetchw(va); /* xdp_frame data area */
        net_prefetch(va + rx_headroom);
 
@@ -1608,7 +1609,7 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 
                addr = page_pool_get_dma_addr(au->page);
                dma_sync_single_for_cpu(rq->pdev, addr + wi->offset,
-                                       frag_consumed_bytes, DMA_FROM_DEVICE);
+                                       frag_consumed_bytes, rq->buff.map_dir);
 
                if (!xdp_buff_has_frags(&xdp)) {
                        /* Init on the first fragment to avoid cold cache access
@@ -1905,7 +1906,7 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w
        mlx5e_fill_skb_data(skb, rq, au, byte_cnt, frag_offset);
        /* copy header */
        addr = page_pool_get_dma_addr(head_au->page);
-       mlx5e_copy_skb_header(rq->pdev, skb, head_au->page, addr,
+       mlx5e_copy_skb_header(rq, skb, head_au->page, addr,
                              head_offset, head_offset, headlen);
        /* skb linear part was allocated with headlen and aligned to long */
        skb->tail += headlen;
@@ -1939,7 +1940,7 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
 
        addr = page_pool_get_dma_addr(au->page);
        dma_sync_single_range_for_cpu(rq->pdev, addr, head_offset,
-                                     frag_size, DMA_FROM_DEVICE);
+                                     frag_size, rq->buff.map_dir);
        net_prefetch(data);
 
        prog = rcu_dereference(rq->xdp_prog);
@@ -1987,7 +1988,7 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
 
        if (likely(frag_size <= BIT(MLX5E_SHAMPO_LOG_MAX_HEADER_ENTRY_SIZE))) {
                /* build SKB around header */
-               dma_sync_single_range_for_cpu(rq->pdev, head->addr, 0, frag_size, DMA_FROM_DEVICE);
+               dma_sync_single_range_for_cpu(rq->pdev, head->addr, 0, frag_size, rq->buff.map_dir);
                prefetchw(hdr);
                prefetch(data);
                skb = mlx5e_build_linear_skb(rq, hdr, frag_size, rx_headroom, head_size, 0);
@@ -2009,7 +2010,7 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
                }
 
                prefetchw(skb->data);
-               mlx5e_copy_skb_header(rq->pdev, skb, head->page, head->addr,
+               mlx5e_copy_skb_header(rq, skb, head->page, head->addr,
                                      head_offset + rx_headroom,
                                      rx_headroom, head_size);
                /* skb linear part was allocated with headlen and aligned to long */