cxgb3: map entire Rx page, feed map+offset to Rx ring.

DMA mapping can be expensive in the presence of iommus.
Reduce the Rx iommu activity by mapping an entire page, and provide the H/W
the mapped address + offset of the current page chunk.
Reserve bits at the end of the page to track mapping references, so the page
can be unmapped.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/cxgb3/adapter.h b/drivers/net/cxgb3/adapter.h
index 2cf6c9299f22..714df2b675e6 100644
--- a/drivers/net/cxgb3/adapter.h
+++ b/drivers/net/cxgb3/adapter.h
@@ -85,6 +85,8 @@ struct fl_pg_chunk {
         struct page *page;
         void *va;
         unsigned int offset;
+        u64 *p_cnt;
+        DECLARE_PCI_UNMAP_ADDR(mapping);
 };
 
 struct rx_desc;
@@ -101,6 +103,7 @@ struct sge_fl {                     /* SGE per free-buffer list state */
         struct fl_pg_chunk pg_chunk;/* page chunk cache */
         unsigned int use_pages;     /* whether FL uses pages or sk_buffs */
         unsigned int order;         /* order of page allocations */
+        unsigned int alloc_size;    /* size of allocated buffer */
         struct rx_desc *desc;       /* address of HW Rx descriptor ring */
         struct rx_sw_desc *sdesc;   /* address of SW Rx descriptor ring */
         dma_addr_t   phys_addr;     /* physical address of HW ring start */