[BNX2]: Add fast path code to handle RX pages.

Add function to reuse a page in case of allocation or other errors.
Add code to construct the completed SKB with the additional data in
the pages.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 138 insertions, 6 deletions

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index 38e8e31cabf3..6c0fc8a99c67 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -2411,6 +2411,55 @@ bnx2_tx_int(struct bnx2 *bp)
         }
 }
 
+static void
+bnx2_reuse_rx_skb_pages(struct bnx2 *bp, struct sk_buff *skb, int count)
+{
+        struct sw_pg *cons_rx_pg, *prod_rx_pg;
+        struct rx_bd *cons_bd, *prod_bd;
+        dma_addr_t mapping;
+        int i;
+        u16 hw_prod = bp->rx_pg_prod, prod;
+        u16 cons = bp->rx_pg_cons;
+
+        for (i = 0; i < count; i++) {
+                prod = RX_PG_RING_IDX(hw_prod);
+
+                prod_rx_pg = &bp->rx_pg_ring[prod];
+                cons_rx_pg = &bp->rx_pg_ring[cons];
+                cons_bd = &bp->rx_pg_desc_ring[RX_RING(cons)][RX_IDX(cons)];
+                prod_bd = &bp->rx_pg_desc_ring[RX_RING(prod)][RX_IDX(prod)];
+
+                if (i == 0 && skb) {
+                        struct page *page;
+                        struct skb_shared_info *shinfo;
+
+                        shinfo = skb_shinfo(skb);
+                        shinfo->nr_frags--;
+                        page = shinfo->frags[shinfo->nr_frags].page;
+                        shinfo->frags[shinfo->nr_frags].page = NULL;
+                        mapping = pci_map_page(bp->pdev, page, 0, PAGE_SIZE,
+                                               PCI_DMA_FROMDEVICE);
+                        cons_rx_pg->page = page;
+                        pci_unmap_addr_set(cons_rx_pg, mapping, mapping);
+                        dev_kfree_skb(skb);
+                }
+                if (prod != cons) {
+                        prod_rx_pg->page = cons_rx_pg->page;
+                        cons_rx_pg->page = NULL;
+                        pci_unmap_addr_set(prod_rx_pg, mapping,
+                                pci_unmap_addr(cons_rx_pg, mapping));
+
+                        prod_bd->rx_bd_haddr_hi = cons_bd->rx_bd_haddr_hi;
+                        prod_bd->rx_bd_haddr_lo = cons_bd->rx_bd_haddr_lo;
+
+                }
+                cons = RX_PG_RING_IDX(NEXT_RX_BD(cons));
+                hw_prod = NEXT_RX_BD(hw_prod);
+        }
+        bp->rx_pg_prod = hw_prod;
+        bp->rx_pg_cons = cons;
+}
+
 static inline void
 bnx2_reuse_rx_skb(struct bnx2 *bp, struct sk_buff *skb,
         u16 cons, u16 prod)
@@ -2443,7 +2492,7 @@ bnx2_reuse_rx_skb(struct bnx2 *bp, struct sk_buff *skb,
 
 static int
 bnx2_rx_skb(struct bnx2 *bp, struct sk_buff *skb, unsigned int len,
-            dma_addr_t dma_addr, u32 ring_idx)
+            unsigned int hdr_len, dma_addr_t dma_addr, u32 ring_idx)
 {
         int err;
         u16 prod = ring_idx & 0xffff;
@@ -2451,6 +2500,12 @@ bnx2_rx_skb(struct bnx2 *bp, struct sk_buff *skb, unsigned int len,
         err = bnx2_alloc_rx_skb(bp, prod);
         if (unlikely(err)) {
                 bnx2_reuse_rx_skb(bp, skb, (u16) (ring_idx >> 16), prod);
+                if (hdr_len) {
+                        unsigned int raw_len = len + 4;
+                        int pages = PAGE_ALIGN(raw_len - hdr_len) >> PAGE_SHIFT;
+
+                        bnx2_reuse_rx_skb_pages(bp, NULL, pages);
+                }
                 return err;
         }
 
@@ -2458,7 +2513,69 @@ bnx2_rx_skb(struct bnx2 *bp, struct sk_buff *skb, unsigned int len,
         pci_unmap_single(bp->pdev, dma_addr, bp->rx_buf_use_size,
                          PCI_DMA_FROMDEVICE);
 
-        skb_put(skb, len);
+        if (hdr_len == 0) {
+                skb_put(skb, len);
+                return 0;
+        } else {
+                unsigned int i, frag_len, frag_size, pages;
+                struct sw_pg *rx_pg;
+                u16 pg_cons = bp->rx_pg_cons;
+                u16 pg_prod = bp->rx_pg_prod;
+
+                frag_size = len + 4 - hdr_len;
+                pages = PAGE_ALIGN(frag_size) >> PAGE_SHIFT;
+                skb_put(skb, hdr_len);
+
+                for (i = 0; i < pages; i++) {
+                        frag_len = min(frag_size, (unsigned int) PAGE_SIZE);
+                        if (unlikely(frag_len <= 4)) {
+                                unsigned int tail = 4 - frag_len;
+
+                                bp->rx_pg_cons = pg_cons;
+                                bp->rx_pg_prod = pg_prod;
+                                bnx2_reuse_rx_skb_pages(bp, NULL, pages - i);
+                                skb->len -= tail;
+                                if (i == 0) {
+                                        skb->tail -= tail;
+                                } else {
+                                        skb_frag_t *frag =
+                                                &skb_shinfo(skb)->frags[i - 1];
+                                        frag->size -= tail;
+                                        skb->data_len -= tail;
+                                        skb->truesize -= tail;
+                                }
+                                return 0;
+                        }
+                        rx_pg = &bp->rx_pg_ring[pg_cons];
+
+                        pci_unmap_page(bp->pdev, pci_unmap_addr(rx_pg, mapping),
+                                       PAGE_SIZE, PCI_DMA_FROMDEVICE);
+
+                        if (i == pages - 1)
+                                frag_len -= 4;
+
+                        skb_fill_page_desc(skb, i, rx_pg->page, 0, frag_len);
+                        rx_pg->page = NULL;
+
+                        err = bnx2_alloc_rx_page(bp, RX_PG_RING_IDX(pg_prod));
+                        if (unlikely(err)) {
+                                bp->rx_pg_cons = pg_cons;
+                                bp->rx_pg_prod = pg_prod;
+                                bnx2_reuse_rx_skb_pages(bp, skb, pages - i);
+                                return err;
+                        }
+
+                        frag_size -= frag_len;
+                        skb->data_len += frag_len;
+                        skb->truesize += frag_len;
+                        skb->len += frag_len;
+
+                        pg_prod = NEXT_RX_BD(pg_prod);
+                        pg_cons = RX_PG_RING_IDX(NEXT_RX_BD(pg_cons));
+                }
+                bp->rx_pg_prod = pg_prod;
+                bp->rx_pg_cons = pg_cons;
+        }
         return 0;
 }
 
@@ -2477,7 +2594,7 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
 {
         u16 hw_cons, sw_cons, sw_ring_cons, sw_prod, sw_ring_prod;
         struct l2_fhdr *rx_hdr;
-        int rx_pkt = 0;
+        int rx_pkt = 0, pg_ring_used = 0;
 
         hw_cons = bnx2_get_hw_rx_cons(bp);
         sw_cons = bp->rx_cons;
@@ -2488,7 +2605,7 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
          */
         rmb();
         while (sw_cons != hw_cons) {
-                unsigned int len;
+                unsigned int len, hdr_len;
                 u32 status;
                 struct sw_bd *rx_buf;
                 struct sk_buff *skb;
@@ -2508,7 +2625,7 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
                         bp->rx_offset + RX_COPY_THRESH, PCI_DMA_FROMDEVICE);
 
                 rx_hdr = (struct l2_fhdr *) skb->data;
-                len = rx_hdr->l2_fhdr_pkt_len - 4;
+                len = rx_hdr->l2_fhdr_pkt_len;
 
                 if ((status = rx_hdr->l2_fhdr_status) &
                         (L2_FHDR_ERRORS_BAD_CRC |
@@ -2520,6 +2637,16 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
                         bnx2_reuse_rx_skb(bp, skb, sw_ring_cons, sw_ring_prod);
                         goto next_rx;
                 }
+                hdr_len = 0;
+                if (status & L2_FHDR_STATUS_SPLIT) {
+                        hdr_len = rx_hdr->l2_fhdr_ip_xsum;
+                        pg_ring_used = 1;
+                } else if (len > bp->rx_jumbo_thresh) {
+                        hdr_len = bp->rx_jumbo_thresh;
+                        pg_ring_used = 1;
+                }
+
+                len -= 4;
 
                 if (len <= bp->rx_copy_thresh) {
                         struct sk_buff *new_skb;
@@ -2541,7 +2668,7 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
                                 sw_ring_cons, sw_ring_prod);
 
                         skb = new_skb;
-                } else if (unlikely(bnx2_rx_skb(bp, skb, len, dma_addr,
+                } else if (unlikely(bnx2_rx_skb(bp, skb, len, hdr_len, dma_addr,
                                     (sw_ring_cons << 16) | sw_ring_prod)))
                         goto next_rx;
 
@@ -2593,6 +2720,10 @@ next_rx:
         bp->rx_cons = sw_cons;
         bp->rx_prod = sw_prod;
 
+        if (pg_ring_used)
+                REG_WR16(bp, MB_RX_CID_ADDR + BNX2_L2CTX_HOST_PG_BDIDX,
+                         bp->rx_pg_prod);
+
         REG_WR16(bp, MB_RX_CID_ADDR + BNX2_L2CTX_HOST_BDIDX, sw_prod);
 
         REG_WR(bp, MB_RX_CID_ADDR + BNX2_L2CTX_HOST_BSEQ, bp->rx_prod_bseq);
@@ -4375,6 +4506,7 @@ bnx2_set_rx_ring_size(struct bnx2 *bp, u32 size)
         bp->rx_buf_use_size = rx_size;
         /* hw alignment */
         bp->rx_buf_size = bp->rx_buf_use_size + BNX2_RX_ALIGN;
+        bp->rx_jumbo_thresh = rx_size - bp->rx_offset;
         bp->rx_ring_size = size;
         bp->rx_max_ring = bnx2_find_max_ring(size, MAX_RX_RINGS);
         bp->rx_max_ring_idx = (bp->rx_max_ring * RX_DESC_CNT) - 1;