From c56d91ce38d54c0c0dd8d0e4c6a9e0cfa557152f Mon Sep 17 00:00:00 2001 From: Sunil Goutham Date: Tue, 2 May 2017 18:36:55 +0530 Subject: [PATCH] net: thunderx: Add support for XDP_DROP Adds support for XDP_DROP. Also since in XDP mode there is just a single buffer per page, made changes to recycle DMA mapping info as well along with pages. Signed-off-by: Sunil Goutham Signed-off-by: David S. Miller --- .../net/ethernet/cavium/thunder/nicvf_main.c | 23 +++++- .../ethernet/cavium/thunder/nicvf_queues.c | 77 ++++++++++++++----- .../ethernet/cavium/thunder/nicvf_queues.h | 4 +- 3 files changed, 79 insertions(+), 25 deletions(-) diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c index 9c48873350f8..a58cc1e7b94a 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include "nic_reg.h" @@ -505,6 +506,7 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct cqe_rx_t *cqe_rx) { struct xdp_buff xdp; + struct page *page; u32 action; u16 len; u64 dma_addr, cpu_addr; @@ -527,12 +529,27 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, switch (action) { case XDP_PASS: case XDP_TX: - case XDP_ABORTED: - case XDP_DROP: /* Pass on all packets to network stack */ return false; default: bpf_warn_invalid_xdp_action(action); + case XDP_ABORTED: + trace_xdp_exception(nic->netdev, prog, action); + case XDP_DROP: + page = virt_to_page(xdp.data); + /* Check if it's a recycled page, if not + * unmap the DMA mapping. + * + * Recycled page holds an extra reference. + */ + if (page_ref_count(page) == 1) { + dma_addr &= PAGE_MASK; + dma_unmap_page_attrs(&nic->pdev->dev, dma_addr, + RCV_FRAG_LEN, DMA_FROM_DEVICE, + DMA_ATTR_SKIP_CPU_SYNC); + } + put_page(page); + return true; } return false; } @@ -645,7 +662,7 @@ static void nicvf_rcv_pkt_handler(struct net_device *netdev, if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx)) return; - skb = nicvf_get_rcv_skb(snic, cqe_rx); + skb = nicvf_get_rcv_skb(snic, cqe_rx, nic->xdp_prog ? true : false); if (!skb) { netdev_dbg(nic->netdev, "Packet not received\n"); return; diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c index 8c3c571568aa..5009f497e64f 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c @@ -117,6 +117,7 @@ static struct pgcache *nicvf_alloc_page(struct nicvf *nic, /* Save the page in page cache */ pgcache->page = page; + pgcache->dma_addr = 0; rbdr->pgalloc++; } @@ -144,7 +145,7 @@ static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, struct rbdr *rbdr, /* Check if request can be accomodated in previous allocated page. * But in XDP mode only one buffer per page is permitted. */ - if (!nic->pnicvf->xdp_prog && nic->rb_page && + if (!rbdr->is_xdp && nic->rb_page && ((nic->rb_page_offset + buf_len) <= PAGE_SIZE)) { nic->rb_pageref++; goto ret; @@ -165,18 +166,24 @@ static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, struct rbdr *rbdr, if (pgcache) nic->rb_page = pgcache->page; ret: - /* HW will ensure data coherency, CPU sync not required */ - *rbuf = (u64)dma_map_page_attrs(&nic->pdev->dev, nic->rb_page, - nic->rb_page_offset, buf_len, - DMA_FROM_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); - if (dma_mapping_error(&nic->pdev->dev, (dma_addr_t)*rbuf)) { - if (!nic->rb_page_offset) - __free_pages(nic->rb_page, 0); - nic->rb_page = NULL; - return -ENOMEM; + if (rbdr->is_xdp && pgcache && pgcache->dma_addr) { + *rbuf = pgcache->dma_addr; + } else { + /* HW will ensure data coherency, CPU sync not required */ + *rbuf = (u64)dma_map_page_attrs(&nic->pdev->dev, nic->rb_page, + nic->rb_page_offset, buf_len, + DMA_FROM_DEVICE, + DMA_ATTR_SKIP_CPU_SYNC); + if (dma_mapping_error(&nic->pdev->dev, (dma_addr_t)*rbuf)) { + if (!nic->rb_page_offset) + __free_pages(nic->rb_page, 0); + nic->rb_page = NULL; + return -ENOMEM; + } + if (pgcache) + pgcache->dma_addr = *rbuf; + nic->rb_page_offset += buf_len; } - nic->rb_page_offset += buf_len; return 0; } @@ -230,8 +237,16 @@ static int nicvf_init_rbdr(struct nicvf *nic, struct rbdr *rbdr, * On embedded platforms i.e 81xx/83xx available memory itself * is low and minimum ring size of RBDR is 8K, that takes away * lots of memory. + * + * But for XDP it has to be a single buffer per page. */ - rbdr->pgcnt = ring_len / (PAGE_SIZE / buf_size); + if (!nic->pnicvf->xdp_prog) { + rbdr->pgcnt = ring_len / (PAGE_SIZE / buf_size); + rbdr->is_xdp = false; + } else { + rbdr->pgcnt = ring_len; + rbdr->is_xdp = true; + } rbdr->pgcnt = roundup_pow_of_two(rbdr->pgcnt); rbdr->pgcache = kzalloc(sizeof(*rbdr->pgcache) * rbdr->pgcnt, GFP_KERNEL); @@ -1454,8 +1469,31 @@ static inline unsigned frag_num(unsigned i) #endif } +static void nicvf_unmap_rcv_buffer(struct nicvf *nic, u64 dma_addr, + u64 buf_addr, bool xdp) +{ + struct page *page = NULL; + int len = RCV_FRAG_LEN; + + if (xdp) { + page = virt_to_page(phys_to_virt(buf_addr)); + /* Check if it's a recycled page, if not + * unmap the DMA mapping. + * + * Recycled page holds an extra reference. + */ + if (page_ref_count(page) != 1) + return; + /* Receive buffers in XDP mode are mapped from page start */ + dma_addr &= PAGE_MASK; + } + dma_unmap_page_attrs(&nic->pdev->dev, dma_addr, len, + DMA_FROM_DEVICE, DMA_ATTR_SKIP_CPU_SYNC); +} + /* Returns SKB for a received packet */ -struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx) +struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, + struct cqe_rx_t *cqe_rx, bool xdp) { int frag; int payload_len = 0; @@ -1490,10 +1528,9 @@ struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx) if (!frag) { /* First fragment */ - dma_unmap_page_attrs(&nic->pdev->dev, - *rb_ptrs - cqe_rx->align_pad, - RCV_FRAG_LEN, DMA_FROM_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); + nicvf_unmap_rcv_buffer(nic, + *rb_ptrs - cqe_rx->align_pad, + phys_addr, xdp); skb = nicvf_rb_ptr_to_skb(nic, phys_addr - cqe_rx->align_pad, payload_len); @@ -1503,9 +1540,7 @@ struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx) skb_put(skb, payload_len); } else { /* Add fragments */ - dma_unmap_page_attrs(&nic->pdev->dev, *rb_ptrs, - RCV_FRAG_LEN, DMA_FROM_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); + nicvf_unmap_rcv_buffer(nic, *rb_ptrs, phys_addr, xdp); page = virt_to_page(phys_to_virt(phys_addr)); offset = phys_to_virt(phys_addr) - page_address(page); skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h index 07136a2819ff..db04c0e33c6c 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h +++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h @@ -228,6 +228,7 @@ struct rbdr { u32 head; u32 tail; struct q_desc_mem dmem; + bool is_xdp; /* For page recycling */ int pgidx; @@ -339,7 +340,8 @@ void nicvf_sq_free_used_descs(struct net_device *netdev, int nicvf_sq_append_skb(struct nicvf *nic, struct snd_queue *sq, struct sk_buff *skb, u8 sq_num); -struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx); +struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, + struct cqe_rx_t *cqe_rx, bool xdp); void nicvf_rbdr_task(unsigned long data); void nicvf_rbdr_work(struct work_struct *work);