From: Ilias Apalodimas <ilias.apalodi...@linaro.org>

Use the page_pool api for allocations and DMA handling instead of
__dev_alloc_page()/dma_map_page() and free_page()/dma_unmap_page().

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.

Although XDP is not a part of the driver yet, the current implementation
is allocating one page per packet, thus there's no performance penalty from
using the API.

For now pages are unmapped via page_pool_unmap_page() before packets
travel into the network stack, as it doesn't have a return hook yet.
Given this call cleared the page_pool state, it is safe to let the
page be returned to the normal page allocator.

Signed-off-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
Signed-off-by: Jesper Dangaard Brouer <bro...@redhat.com>
---
 drivers/net/ethernet/marvell/Kconfig  |    1 +
 drivers/net/ethernet/marvell/mvneta.c |   56 ++++++++++++++++++++++++---------
 2 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/marvell/Kconfig 
b/drivers/net/ethernet/marvell/Kconfig
index 3238aa7f5dac..3325abe67465 100644
--- a/drivers/net/ethernet/marvell/Kconfig
+++ b/drivers/net/ethernet/marvell/Kconfig
@@ -60,6 +60,7 @@ 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
diff --git a/drivers/net/ethernet/marvell/mvneta.c 
b/drivers/net/ethernet/marvell/mvneta.c
index 5bfd349bf41a..2354421fe96f 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -33,6 +33,7 @@
 #include <linux/skbuff.h>
 #include <net/hwbm.h>
 #include "mvneta_bm.h"
+#include <net/page_pool.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
 #include <net/tso.h>
@@ -624,6 +625,9 @@ struct mvneta_rx_queue {
        struct sk_buff *skb;
        int left_size;
 
+       /* page pool */
+       struct page_pool *page_pool;
+
        /* error counters */
        u32 skb_alloc_err;
        u32 refill_err;
@@ -1813,17 +1817,11 @@ static int mvneta_rx_refill(struct mvneta_port *pp,
        dma_addr_t phys_addr;
        struct page *page;
 
-       page = __dev_alloc_page(gfp_mask);
+       page = page_pool_dev_alloc_pages(rxq->page_pool);
        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 = page_pool_get_dma_addr(page);
 
        phys_addr += pp->rx_offset_correction;
        mvneta_rx_desc_fill(rx_desc, phys_addr, page, rxq);
@@ -1892,10 +1890,11 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp,
                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 (rxq->page_pool)
+               page_pool_destroy(rxq->page_pool);
 }
 
 static inline
@@ -2010,8 +2009,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
                                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_unmap_page(rxq->page_pool, page);
                                rxq->left_size -= frag_size;
                        }
                } else {
@@ -2041,8 +2039,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
                                                frag_offset, frag_size,
                                                PAGE_SIZE);
 
-                               dma_unmap_page(dev->dev.parent, phys_addr,
-                                              PAGE_SIZE, DMA_FROM_DEVICE);
+                               page_pool_unmap_page(rxq->page_pool, page);
 
                                rxq->left_size -= frag_size;
                        }
@@ -2828,11 +2825,37 @@ static int mvneta_poll(struct napi_struct *napi, int 
budget)
        return rx_done;
 }
 
+static int mvneta_create_page_pool(struct mvneta_port *pp,
+                                  struct mvneta_rx_queue *rxq, int num)
+{
+       struct page_pool_params pp_params = { 0 };
+       int err = 0;
+
+       pp_params.order = 0;
+       /* internal DMA mapping in page_pool */
+       pp_params.flags = PP_FLAG_DMA_MAP;
+       pp_params.pool_size = num;
+       pp_params.nid = NUMA_NO_NODE;
+       pp_params.dev = pp->dev->dev.parent;
+       pp_params.dma_dir = DMA_FROM_DEVICE;
+
+       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;
+}
+
 /* 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 = 0;
+
+       if (mvneta_create_page_pool(pp, rxq, num))
+               goto out;
 
        for (i = 0; i < num; i++) {
                memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc));
@@ -2848,6 +2871,7 @@ static int mvneta_rxq_fill(struct mvneta_port *pp, struct 
mvneta_rx_queue *rxq,
        /* Add this number of RX descriptors as non occupied (ready to
         * get packets)
         */
+out:
        mvneta_rxq_non_occup_desc_add(pp, rxq, i);
 
        return i;

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