[PATCH] powerpc: node-aware dma allocations

Make sure dma_alloc_coherent allocates memory from the local node.  This
is important on Cell where we avoid going through the slow cpu
interconnect.

Note:  I could only test this patch on Cell, it should be verified on
some pseries machine by those that have the hardware.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 11 insertions, 8 deletions

diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 4eba60a32890..cbb794556d02 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -536,11 +536,12 @@ void iommu_unmap_single(struct iommu_table *tbl, dma_addr_t dma_handle,
  * to the dma address (mapping) of the first page.
  */
 void *iommu_alloc_coherent(struct iommu_table *tbl, size_t size,
-                dma_addr_t *dma_handle, unsigned long mask, gfp_t flag)
+                dma_addr_t *dma_handle, unsigned long mask, gfp_t flag, int node)
 {
         void *ret = NULL;
         dma_addr_t mapping;
         unsigned int npages, order;
+        struct page *page;
 
         size = PAGE_ALIGN(size);
         npages = size >> PAGE_SHIFT;
@@ -560,9 +561,10 @@ void *iommu_alloc_coherent(struct iommu_table *tbl, size_t size,
                 return NULL;
 
         /* Alloc enough pages (and possibly more) */
-        ret = (void *)__get_free_pages(flag, order);
-        if (!ret)
+        page = alloc_pages_node(flag, order, node);
+        if (!page)
                 return NULL;
+        ret = page_address(page);
         memset(ret, 0, size);
 
         /* Set up tces to cover the allocated range */
@@ -570,9 +572,9 @@ void *iommu_alloc_coherent(struct iommu_table *tbl, size_t size,
                               mask >> PAGE_SHIFT, order);
         if (mapping == DMA_ERROR_CODE) {
                 free_pages((unsigned long)ret, order);
-                ret = NULL;
-        } else
-                *dma_handle = mapping;
+                return NULL;
+        }
+        *dma_handle = mapping;
         return ret;
 }
 
diff --git a/arch/powerpc/kernel/pci_iommu.c b/arch/powerpc/kernel/pci_iommu.c
index 48aa82d01624..7fb4cca021be 100644
--- a/arch/powerpc/kernel/pci_iommu.c
+++ b/arch/powerpc/kernel/pci_iommu.c
@@ -86,7 +86,8 @@ static void *pci_iommu_alloc_coherent(struct device *hwdev, size_t size,
                            dma_addr_t *dma_handle, gfp_t flag)
 {
         return iommu_alloc_coherent(device_to_table(hwdev), size, dma_handle,
-                        device_to_mask(hwdev), flag);
+                        device_to_mask(hwdev), flag,
+                        pcibus_to_node(to_pci_dev(hwdev)->bus));
 }
 
 static void pci_iommu_free_coherent(struct device *hwdev, size_t size,
diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index fe92727aca30..e746686d48b8 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -394,7 +394,7 @@ static void *vio_alloc_coherent(struct device *dev, size_t size,
                            dma_addr_t *dma_handle, gfp_t flag)
 {
         return iommu_alloc_coherent(to_vio_dev(dev)->iommu_table, size,
-                        dma_handle, ~0ul, flag);
+                        dma_handle, ~0ul, flag, -1);
 }
 
 static void vio_free_coherent(struct device *dev, size_t size,