1 From 160f006a6fe904177cbca867c48dfb6d27262dd5 Mon Sep 17 00:00:00 2001
2 From: Lorenzo Bianconi <lorenzo@kernel.org>
3 Date: Sat, 19 Oct 2019 10:13:22 +0200
4 Subject: [PATCH 2/7] net: mvneta: introduce page pool API for sw buffer
7 Use the page_pool api for allocations and DMA handling instead of
8 __dev_alloc_page()/dma_map_page() and free_page()/dma_unmap_page().
9 Pages are unmapped using page_pool_release_page before packets
10 go into the network stack.
12 The page_pool API offers buffer recycling capabilities for XDP but
13 allocates one page per packet, unless the driver splits and manages
15 This is a preliminary patch to add XDP support to mvneta driver
17 Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
18 Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
19 Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
20 Signed-off-by: David S. Miller <davem@davemloft.net>
22 drivers/net/ethernet/marvell/Kconfig | 1 +
23 drivers/net/ethernet/marvell/mvneta.c | 83 +++++++++++++++++++++------
24 2 files changed, 65 insertions(+), 19 deletions(-)
26 --- a/drivers/net/ethernet/marvell/Kconfig
27 +++ b/drivers/net/ethernet/marvell/Kconfig
28 @@ -61,6 +61,7 @@ config MVNETA
29 depends on ARCH_MVEBU || COMPILE_TEST
34 This driver supports the network interface units in the
35 Marvell ARMADA XP, ARMADA 370, ARMADA 38x and
36 --- a/drivers/net/ethernet/marvell/mvneta.c
37 +++ b/drivers/net/ethernet/marvell/mvneta.c
42 +#include <net/page_pool.h>
45 #define MVNETA_RXQ_CONFIG_REG(q) (0x1400 + ((q) << 2))
46 @@ -605,6 +606,10 @@ struct mvneta_rx_queue {
51 + struct page_pool *page_pool;
52 + struct xdp_rxq_info xdp_rxq;
54 /* Virtual address of the RX buffer */
57 @@ -1823,23 +1828,21 @@ static int mvneta_rx_refill(struct mvnet
58 struct mvneta_rx_queue *rxq,
61 + enum dma_data_direction dma_dir;
65 - page = __dev_alloc_page(gfp_mask);
66 + page = page_pool_alloc_pages(rxq->page_pool,
67 + gfp_mask | __GFP_NOWARN);
71 - /* map page for use */
72 - phys_addr = dma_map_page(pp->dev->dev.parent, page, 0, PAGE_SIZE,
74 - if (unlikely(dma_mapping_error(pp->dev->dev.parent, phys_addr))) {
79 - phys_addr += pp->rx_offset_correction;
80 + phys_addr = page_pool_get_dma_addr(page) + pp->rx_offset_correction;
81 + dma_dir = page_pool_get_dma_dir(rxq->page_pool);
82 + dma_sync_single_for_device(pp->dev->dev.parent, phys_addr,
83 + PAGE_SIZE, dma_dir);
84 mvneta_rx_desc_fill(rx_desc, phys_addr, page, rxq);
89 @@ -1905,10 +1908,12 @@ static void mvneta_rxq_drop_pkts(struct
90 if (!data || !(rx_desc->buf_phys_addr))
93 - dma_unmap_page(pp->dev->dev.parent, rx_desc->buf_phys_addr,
94 - PAGE_SIZE, DMA_FROM_DEVICE);
96 + page_pool_put_page(rxq->page_pool, data, false);
98 + if (xdp_rxq_info_is_reg(&rxq->xdp_rxq))
99 + xdp_rxq_info_unreg(&rxq->xdp_rxq);
100 + page_pool_destroy(rxq->page_pool);
101 + rxq->page_pool = NULL;
105 @@ -2045,8 +2050,7 @@ static int mvneta_rx_swbm(struct napi_st
106 skb_add_rx_frag(rxq->skb, frag_num, page,
107 frag_offset, frag_size,
109 - dma_unmap_page(dev->dev.parent, phys_addr,
110 - PAGE_SIZE, DMA_FROM_DEVICE);
111 + page_pool_release_page(rxq->page_pool, page);
112 rxq->left_size -= frag_size;
115 @@ -2076,9 +2080,7 @@ static int mvneta_rx_swbm(struct napi_st
116 frag_offset, frag_size,
119 - dma_unmap_page(dev->dev.parent, phys_addr,
120 - PAGE_SIZE, DMA_FROM_DEVICE);
122 + page_pool_release_page(rxq->page_pool, page);
123 rxq->left_size -= frag_size;
125 } /* Middle or Last descriptor */
126 @@ -2845,11 +2847,54 @@ static int mvneta_poll(struct napi_struc
130 +static int mvneta_create_page_pool(struct mvneta_port *pp,
131 + struct mvneta_rx_queue *rxq, int size)
133 + struct page_pool_params pp_params = {
135 + .flags = PP_FLAG_DMA_MAP,
137 + .nid = cpu_to_node(0),
138 + .dev = pp->dev->dev.parent,
139 + .dma_dir = DMA_FROM_DEVICE,
143 + rxq->page_pool = page_pool_create(&pp_params);
144 + if (IS_ERR(rxq->page_pool)) {
145 + err = PTR_ERR(rxq->page_pool);
146 + rxq->page_pool = NULL;
150 + err = xdp_rxq_info_reg(&rxq->xdp_rxq, pp->dev, rxq->id);
154 + err = xdp_rxq_info_reg_mem_model(&rxq->xdp_rxq, MEM_TYPE_PAGE_POOL,
157 + goto err_unregister_rxq;
162 + xdp_rxq_info_unreg(&rxq->xdp_rxq);
164 + page_pool_destroy(rxq->page_pool);
165 + rxq->page_pool = NULL;
169 /* Handle rxq fill: allocates rxq skbs; called when initializing a port */
170 static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
176 + err = mvneta_create_page_pool(pp, rxq, num);
180 for (i = 0; i < num; i++) {
181 memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc));