net/mlx5e: Convert over to netmem

mlx5e_page_frag holds the physical page itself, to naturally support
zc page pools, remove physical page reference from mlx5 and replace it
with netmem_ref, to avoid internal handling in mlx5 for net_iov backed
pages.

SHAMPO can issue packets that are not split into header and data. These
packets will be dropped if the data part resides in a net_iov as the
driver can't read into this area.

No performance degradation observed.

Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250616141441.1243044-9-mbloch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index c329de1d4f0ad070fe1649c195e6d57ab100dd49..65a73913b9a24fe38d58bdb98ead5ce74058f34a 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -553,7 +553,7 @@ struct mlx5e_icosq {
 } ____cacheline_aligned_in_smp;
 
 struct mlx5e_frag_page {
-       struct page *page;
+       netmem_ref netmem;
        u16 frags;
 };
 

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index e34ef53ebd0e0187f8c4152a5dc7fa08ae072f66..2bb32082bfccdc85d26987f792eb8c1047e44dd0 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -273,33 +273,32 @@ static inline u32 mlx5e_decompress_cqes_start(struct mlx5e_rq *rq,
 
 #define MLX5E_PAGECNT_BIAS_MAX (PAGE_SIZE / 64)
 
-static int mlx5e_page_alloc_fragmented(struct page_pool *pool,
+static int mlx5e_page_alloc_fragmented(struct page_pool *pp,
                                       struct mlx5e_frag_page *frag_page)
 {
-       struct page *page;
+       netmem_ref netmem = page_pool_dev_alloc_netmems(pp);
 
-       page = page_pool_dev_alloc_pages(pool);
-       if (unlikely(!page))
+       if (unlikely(!netmem))
                return -ENOMEM;
 
-       page_pool_fragment_page(page, MLX5E_PAGECNT_BIAS_MAX);
+       page_pool_fragment_netmem(netmem, MLX5E_PAGECNT_BIAS_MAX);
 
        *frag_page = (struct mlx5e_frag_page) {
-               .page   = page,
+               .netmem = netmem,
                .frags  = 0,
        };
 
        return 0;
 }
 
-static void mlx5e_page_release_fragmented(struct page_pool *pool,
+static void mlx5e_page_release_fragmented(struct page_pool *pp,
                                          struct mlx5e_frag_page *frag_page)
 {
        u16 drain_count = MLX5E_PAGECNT_BIAS_MAX - frag_page->frags;
-       struct page *page = frag_page->page;
+       netmem_ref netmem = frag_page->netmem;
 
-       if (page_pool_unref_page(page, drain_count) == 0)
-               page_pool_put_unrefed_page(pool, page, -1, true);
+       if (page_pool_unref_netmem(netmem, drain_count) == 0)
+               page_pool_put_unrefed_netmem(pp, netmem, -1, true);
 }
 
 static inline int mlx5e_get_rx_frag(struct mlx5e_rq *rq,
@@ -359,7 +358,7 @@ static int mlx5e_alloc_rx_wqe(struct mlx5e_rq *rq, struct mlx5e_rx_wqe_cyc *wqe,
                frag->flags &= ~BIT(MLX5E_WQE_FRAG_SKIP_RELEASE);
 
                headroom = i == 0 ? rq->buff.headroom : 0;
-               addr = page_pool_get_dma_addr(frag->frag_page->page);
+               addr = page_pool_get_dma_addr_netmem(frag->frag_page->netmem);
                wqe->data[i].addr = cpu_to_be64(addr + frag->offset + headroom);
        }
 
@@ -500,9 +499,10 @@ mlx5e_add_skb_shared_info_frag(struct mlx5e_rq *rq, struct skb_shared_info *sinf
                               struct xdp_buff *xdp, struct mlx5e_frag_page *frag_page,
                               u32 frag_offset, u32 len)
 {
+       netmem_ref netmem = frag_page->netmem;
        skb_frag_t *frag;
 
-       dma_addr_t addr = page_pool_get_dma_addr(frag_page->page);
+       dma_addr_t addr = page_pool_get_dma_addr_netmem(netmem);
 
        dma_sync_single_for_cpu(rq->pdev, addr + frag_offset, len, rq->buff.map_dir);
        if (!xdp_buff_has_frags(xdp)) {
@@ -515,9 +515,9 @@ mlx5e_add_skb_shared_info_frag(struct mlx5e_rq *rq, struct skb_shared_info *sinf
        }
 
        frag = &sinfo->frags[sinfo->nr_frags++];
-       skb_frag_fill_page_desc(frag, frag_page->page, frag_offset, len);
+       skb_frag_fill_netmem_desc(frag, netmem, frag_offset, len);
 
-       if (page_is_pfmemalloc(frag_page->page))
+       if (netmem_is_pfmemalloc(netmem))
                xdp_buff_set_frag_pfmemalloc(xdp);
        sinfo->xdp_frags_size += len;
 }
@@ -528,27 +528,29 @@ mlx5e_add_skb_frag(struct mlx5e_rq *rq, struct sk_buff *skb,
                   u32 frag_offset, u32 len,
                   unsigned int truesize)
 {
-       dma_addr_t addr = page_pool_get_dma_addr(frag_page->page);
+       dma_addr_t addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
        u8 next_frag = skb_shinfo(skb)->nr_frags;
+       netmem_ref netmem = frag_page->netmem;
 
        dma_sync_single_for_cpu(rq->pdev, addr + frag_offset, len,
                                rq->buff.map_dir);
 
-       if (skb_can_coalesce(skb, next_frag, frag_page->page, frag_offset)) {
+       if (skb_can_coalesce_netmem(skb, next_frag, netmem, frag_offset)) {
                skb_coalesce_rx_frag(skb, next_frag - 1, len, truesize);
-       } else {
-               frag_page->frags++;
-               skb_add_rx_frag(skb, next_frag, frag_page->page,
-                               frag_offset, len, truesize);
+               return;
        }
+
+       frag_page->frags++;
+       skb_add_rx_frag_netmem(skb, next_frag, netmem,
+                              frag_offset, len, truesize);
 }
 
 static inline void
 mlx5e_copy_skb_header(struct mlx5e_rq *rq, struct sk_buff *skb,
-                     struct page *page, dma_addr_t addr,
+                     netmem_ref netmem, dma_addr_t addr,
                      int offset_from, int dma_offset, u32 headlen)
 {
-       const void *from = page_address(page) + offset_from;
+       const void *from = netmem_address(netmem) + offset_from;
        /* Aligning len to sizeof(long) optimizes memcpy performance */
        unsigned int len = ALIGN(headlen, sizeof(long));
 
@@ -685,7 +687,7 @@ static int mlx5e_build_shampo_hd_umr(struct mlx5e_rq *rq,
                if (unlikely(err))
                        goto err_unmap;
 
-               addr = page_pool_get_dma_addr(frag_page->page);
+               addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
 
                for (int j = 0; j < MLX5E_SHAMPO_WQ_HEADER_PER_PAGE; j++) {
                        header_offset = mlx5e_shampo_hd_offset(index++);
@@ -796,7 +798,8 @@ static int mlx5e_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
                err = mlx5e_page_alloc_fragmented(rq->page_pool, frag_page);
                if (unlikely(err))
                        goto err_unmap;
-               addr = page_pool_get_dma_addr(frag_page->page);
+
+               addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
                umr_wqe->inline_mtts[i] = (struct mlx5_mtt) {
                        .ptag = cpu_to_be64(addr | MLX5_EN_WR),
                };
@@ -1216,7 +1219,7 @@ static void *mlx5e_shampo_get_packet_hd(struct mlx5e_rq *rq, u16 header_index)
        struct mlx5e_frag_page *frag_page = mlx5e_shampo_hd_to_frag_page(rq, header_index);
        u16 head_offset = mlx5e_shampo_hd_offset(header_index) + rq->buff.headroom;
 
-       return page_address(frag_page->page) + head_offset;
+       return netmem_address(frag_page->netmem) + head_offset;
 }
 
 static void mlx5e_shampo_update_ipv4_udp_hdr(struct mlx5e_rq *rq, struct iphdr *ipv4)
@@ -1677,11 +1680,11 @@ mlx5e_skb_from_cqe_linear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi,
        dma_addr_t addr;
        u32 frag_size;
 
-       va             = page_address(frag_page->page) + wi->offset;
+       va             = netmem_address(frag_page->netmem) + wi->offset;
        data           = va + rx_headroom;
        frag_size      = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);
 
-       addr = page_pool_get_dma_addr(frag_page->page);
+       addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
        dma_sync_single_range_for_cpu(rq->pdev, addr, wi->offset,
                                      frag_size, rq->buff.map_dir);
        net_prefetch(data);
@@ -1731,10 +1734,10 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 
        frag_page = wi->frag_page;
 
-       va = page_address(frag_page->page) + wi->offset;
+       va = netmem_address(frag_page->netmem) + wi->offset;
        frag_consumed_bytes = min_t(u32, frag_info->frag_size, cqe_bcnt);
 
-       addr = page_pool_get_dma_addr(frag_page->page);
+       addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
        dma_sync_single_range_for_cpu(rq->pdev, addr, wi->offset,
                                      rq->buff.frame0_sz, rq->buff.map_dir);
        net_prefetchw(va); /* xdp_frame data area */
@@ -2007,13 +2010,14 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w
 
        if (prog) {
                /* area for bpf_xdp_[store|load]_bytes */
-               net_prefetchw(page_address(frag_page->page) + frag_offset);
+               net_prefetchw(netmem_address(frag_page->netmem) + frag_offset);
                if (unlikely(mlx5e_page_alloc_fragmented(rq->page_pool,
                                                         &wi->linear_page))) {
                        rq->stats->buff_alloc_err++;
                        return NULL;
                }
-               va = page_address(wi->linear_page.page);
+
+               va = netmem_address(wi->linear_page.netmem);
                net_prefetchw(va); /* xdp_frame data area */
                linear_hr = XDP_PACKET_HEADROOM;
                linear_data_len = 0;
@@ -2124,8 +2128,8 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w
                        while (++pagep < frag_page);
                }
                /* copy header */
-               addr = page_pool_get_dma_addr(head_page->page);
-               mlx5e_copy_skb_header(rq, skb, head_page->page, addr,
+               addr = page_pool_get_dma_addr_netmem(head_page->netmem);
+               mlx5e_copy_skb_header(rq, skb, head_page->netmem, addr,
                                      head_offset, head_offset, headlen);
                /* skb linear part was allocated with headlen and aligned to long */
                skb->tail += headlen;
@@ -2155,11 +2159,11 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
                return NULL;
        }
 
-       va             = page_address(frag_page->page) + head_offset;
+       va             = netmem_address(frag_page->netmem) + head_offset;
        data           = va + rx_headroom;
        frag_size      = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);
 
-       addr = page_pool_get_dma_addr(frag_page->page);
+       addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
        dma_sync_single_range_for_cpu(rq->pdev, addr, head_offset,
                                      frag_size, rq->buff.map_dir);
        net_prefetch(data);
@@ -2198,16 +2202,19 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
                          struct mlx5_cqe64 *cqe, u16 header_index)
 {
        struct mlx5e_frag_page *frag_page = mlx5e_shampo_hd_to_frag_page(rq, header_index);
-       dma_addr_t page_dma_addr = page_pool_get_dma_addr(frag_page->page);
        u16 head_offset = mlx5e_shampo_hd_offset(header_index);
-       dma_addr_t dma_addr = page_dma_addr + head_offset;
        u16 head_size = cqe->shampo.header_size;
        u16 rx_headroom = rq->buff.headroom;
        struct sk_buff *skb = NULL;
+       dma_addr_t page_dma_addr;
+       dma_addr_t dma_addr;
        void *hdr, *data;
        u32 frag_size;
 
-       hdr             = page_address(frag_page->page) + head_offset;
+       page_dma_addr = page_pool_get_dma_addr_netmem(frag_page->netmem);
+       dma_addr = page_dma_addr + head_offset;
+
+       hdr             = netmem_address(frag_page->netmem) + head_offset;
        data            = hdr + rx_headroom;
        frag_size       = MLX5_SKB_FRAG_SZ(rx_headroom + head_size);
 
@@ -2232,7 +2239,7 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
                }
 
                net_prefetchw(skb->data);
-               mlx5e_copy_skb_header(rq, skb, frag_page->page, dma_addr,
+               mlx5e_copy_skb_header(rq, skb, frag_page->netmem, dma_addr,
                                      head_offset + rx_headroom,
                                      rx_headroom, head_size);
                /* skb linear part was allocated with headlen and aligned to long */
@@ -2326,11 +2333,23 @@ static void mlx5e_handle_rx_cqe_mpwrq_shampo(struct mlx5e_rq *rq, struct mlx5_cq
        }
 
        if (!*skb) {
-               if (likely(head_size))
+               if (likely(head_size)) {
                        *skb = mlx5e_skb_from_cqe_shampo(rq, wi, cqe, header_index);
-               else
-                       *skb = mlx5e_skb_from_cqe_mpwrq_nonlinear(rq, wi, cqe, cqe_bcnt,
-                                                                 data_offset, page_idx);
+               } else {
+                       struct mlx5e_frag_page *frag_page;
+
+                       frag_page = &wi->alloc_units.frag_pages[page_idx];
+                       /* Drop packets with header in unreadable data area to
+                        * prevent the kernel from touching it.
+                        */
+                       if (unlikely(netmem_is_net_iov(frag_page->netmem)))
+                               goto free_hd_entry;
+                       *skb = mlx5e_skb_from_cqe_mpwrq_nonlinear(rq, wi, cqe,
+                                                                 cqe_bcnt,
+                                                                 data_offset,
+                                                                 page_idx);
+               }
+
                if (unlikely(!*skb))
                        goto free_hd_entry;