From 160f006a6fe904177cbca867c48dfb6d27262dd5 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Sat, 19 Oct 2019 10:13:22 +0200 Subject: [PATCH 2/7] net: mvneta: introduce page pool API for sw buffer manager Use the page_pool api for allocations and DMA handling instead of __dev_alloc_page()/dma_map_page() and free_page()/dma_unmap_page(). Pages are unmapped using page_pool_release_page before packets go into the network stack. The page_pool API offers buffer recycling capabilities for XDP but allocates one page per packet, unless the driver splits and manages the allocated page. This is a preliminary patch to add XDP support to mvneta driver Signed-off-by: Ilias Apalodimas Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Lorenzo Bianconi Signed-off-by: David S. Miller --- drivers/net/ethernet/marvell/Kconfig | 1 + drivers/net/ethernet/marvell/mvneta.c | 83 +++++++++++++++++++++------ 2 files changed, 65 insertions(+), 19 deletions(-) --- a/drivers/net/ethernet/marvell/Kconfig +++ b/drivers/net/ethernet/marvell/Kconfig @@ -61,6 +61,7 @@ config MVNETA depends on ARCH_MVEBU || COMPILE_TEST select MVMDIO select PHYLINK + select PAGE_POOL ---help--- This driver supports the network interface units in the Marvell ARMADA XP, ARMADA 370, ARMADA 38x and --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -37,6 +37,7 @@ #include #include #include +#include /* Registers */ #define MVNETA_RXQ_CONFIG_REG(q) (0x1400 + ((q) << 2)) @@ -607,6 +608,10 @@ struct mvneta_rx_queue { u32 pkts_coal; u32 time_coal; + /* page_pool */ + struct page_pool *page_pool; + struct xdp_rxq_info xdp_rxq; + /* Virtual address of the RX buffer */ void **buf_virt_addr; @@ -1825,23 +1830,21 @@ static int mvneta_rx_refill(struct mvnet struct mvneta_rx_queue *rxq, gfp_t gfp_mask) { + enum dma_data_direction dma_dir; dma_addr_t phys_addr; struct page *page; - page = __dev_alloc_page(gfp_mask); + page = page_pool_alloc_pages(rxq->page_pool, + gfp_mask | __GFP_NOWARN); if (!page) return -ENOMEM; - /* map page for use */ - phys_addr = dma_map_page(pp->dev->dev.parent, page, 0, PAGE_SIZE, - DMA_FROM_DEVICE); - if (unlikely(dma_mapping_error(pp->dev->dev.parent, phys_addr))) { - __free_page(page); - return -ENOMEM; - } - - phys_addr += pp->rx_offset_correction; + phys_addr = page_pool_get_dma_addr(page) + pp->rx_offset_correction; + dma_dir = page_pool_get_dma_dir(rxq->page_pool); + dma_sync_single_for_device(pp->dev->dev.parent, phys_addr, + PAGE_SIZE, dma_dir); mvneta_rx_desc_fill(rx_desc, phys_addr, page, rxq); + return 0; } @@ -1907,10 +1910,12 @@ static void mvneta_rxq_drop_pkts(struct if (!data || !(rx_desc->buf_phys_addr)) continue; - dma_unmap_page(pp->dev->dev.parent, rx_desc->buf_phys_addr, - PAGE_SIZE, DMA_FROM_DEVICE); - __free_page(data); + page_pool_put_page(rxq->page_pool, data, false); } + if (xdp_rxq_info_is_reg(&rxq->xdp_rxq)) + xdp_rxq_info_unreg(&rxq->xdp_rxq); + page_pool_destroy(rxq->page_pool); + rxq->page_pool = NULL; } static void @@ -2047,8 +2052,7 @@ static int mvneta_rx_swbm(struct napi_st skb_add_rx_frag(rxq->skb, frag_num, page, frag_offset, frag_size, PAGE_SIZE); - dma_unmap_page(dev->dev.parent, phys_addr, - PAGE_SIZE, DMA_FROM_DEVICE); + page_pool_release_page(rxq->page_pool, page); rxq->left_size -= frag_size; } } else { @@ -2078,9 +2082,7 @@ static int mvneta_rx_swbm(struct napi_st frag_offset, frag_size, PAGE_SIZE); - dma_unmap_page(dev->dev.parent, phys_addr, - PAGE_SIZE, DMA_FROM_DEVICE); - + page_pool_release_page(rxq->page_pool, page); rxq->left_size -= frag_size; } } /* Middle or Last descriptor */ @@ -2847,11 +2849,54 @@ static int mvneta_poll(struct napi_struc return rx_done; } +static int mvneta_create_page_pool(struct mvneta_port *pp, + struct mvneta_rx_queue *rxq, int size) +{ + struct page_pool_params pp_params = { + .order = 0, + .flags = PP_FLAG_DMA_MAP, + .pool_size = size, + .nid = cpu_to_node(0), + .dev = pp->dev->dev.parent, + .dma_dir = DMA_FROM_DEVICE, + }; + int err; + + rxq->page_pool = page_pool_create(&pp_params); + if (IS_ERR(rxq->page_pool)) { + err = PTR_ERR(rxq->page_pool); + rxq->page_pool = NULL; + return err; + } + + err = xdp_rxq_info_reg(&rxq->xdp_rxq, pp->dev, rxq->id); + if (err < 0) + goto err_free_pp; + + err = xdp_rxq_info_reg_mem_model(&rxq->xdp_rxq, MEM_TYPE_PAGE_POOL, + rxq->page_pool); + if (err) + goto err_unregister_rxq; + + return 0; + +err_unregister_rxq: + xdp_rxq_info_unreg(&rxq->xdp_rxq); +err_free_pp: + page_pool_destroy(rxq->page_pool); + rxq->page_pool = NULL; + return err; +} + /* Handle rxq fill: allocates rxq skbs; called when initializing a port */ static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, int num) { - int i; + int i, err; + + err = mvneta_create_page_pool(pp, rxq, num); + if (err < 0) + return err; for (i = 0; i < num; i++) { memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc));