IB/core: dma unmap optimizations

[deliverable/linux.git] / drivers / infiniband / core / umem_odp.c

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index aba47398880ddc5cb932b5935556844274f9c841..40becdb3196e07b97c94ade818af5755bfaae4db 100644 (file)
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -637,7 +637,6 @@ void ib_umem_odp_unmap_dma_pages(struct ib_umem *umem, u64 virt,
                idx = (addr - ib_umem_start(umem)) / PAGE_SIZE;
                if (umem->odp_data->page_list[idx]) {
                        struct page *page = umem->odp_data->page_list[idx];
-                       struct page *head_page = compound_head(page);
                        dma_addr_t dma = umem->odp_data->dma_list[idx];
                        dma_addr_t dma_addr = dma & ODP_DMA_ADDR_MASK;
 
@@ -645,7 +644,8 @@ void ib_umem_odp_unmap_dma_pages(struct ib_umem *umem, u64 virt,
 
                        ib_dma_unmap_page(dev, dma_addr, PAGE_SIZE,
                                          DMA_BIDIRECTIONAL);
-                       if (dma & ODP_WRITE_ALLOWED_BIT)
+                       if (dma & ODP_WRITE_ALLOWED_BIT) {
+                               struct page *head_page = compound_head(page);
                                /*
                                 * set_page_dirty prefers being called with
                                 * the page lock. However, MMU notifiers are
@@ -656,6 +656,7 @@ void ib_umem_odp_unmap_dma_pages(struct ib_umem *umem, u64 virt,
                                 * be removed.
                                 */
                                set_page_dirty(head_page);
+                       }
                        /* on demand pinning support */
                        if (!umem->context->invalidate_range)
                                put_page(page);