x86: cleanup dma_*_coherent functions

All dma_ops implementations support the alloc_coherent and free_coherent
callbacks now. This allows a big simplification of the dma_alloc_coherent
function which is done with this patch. The dma_free_coherent functions is also
cleaned up and calls now the free_coherent callback of the dma_ops
implementation.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 87d4d6964ec2b9ecb5d83ad01c081589218dc303..613332b26e31854dea6178e117afeb2f53e8efd8 100644 (file)
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -241,33 +241,15 @@ int dma_supported(struct device *dev, u64 mask)
 }
 EXPORT_SYMBOL(dma_supported);
 
-/* Allocate DMA memory on node near device */
-static noinline struct page *
-dma_alloc_pages(struct device *dev, gfp_t gfp, unsigned order)
-{
-       int node;
-
-       node = dev_to_node(dev);
-
-       return alloc_pages_node(node, gfp, order);
-}
-
 /*
  * Allocate memory for a coherent mapping.
  */
-void *
+       void *
 dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
                   gfp_t gfp)
 {
        struct dma_mapping_ops *ops = get_dma_ops(dev);
-       void *memory = NULL;
-       struct page *page;
-       unsigned long dma_mask = 0;
-       dma_addr_t bus;
-       int noretry = 0;
-
-       /* ignore region specifiers */
-       gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
+       void *memory;
 
        if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
                return memory;
@@ -276,89 +258,10 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
                dev = &fallback_dev;
                gfp |= GFP_DMA;
        }
-       dma_mask = dev->coherent_dma_mask;
-       if (dma_mask == 0)
-               dma_mask = (gfp & GFP_DMA) ? DMA_24BIT_MASK : DMA_32BIT_MASK;
-
-       /* Device not DMA able */
-       if (dev->dma_mask == NULL)
-               return NULL;
-
-       /* Don't invoke OOM killer or retry in lower 16MB DMA zone */
-       if (gfp & __GFP_DMA)
-               noretry = 1;
-
-#ifdef CONFIG_X86_64
-       /* Why <=? Even when the mask is smaller than 4GB it is often
-          larger than 16MB and in this case we have a chance of
-          finding fitting memory in the next higher zone first. If
-          not retry with true GFP_DMA. -AK */
-       if (dma_mask <= DMA_32BIT_MASK && !(gfp & GFP_DMA)) {
-               gfp |= GFP_DMA32;
-               if (dma_mask < DMA_32BIT_MASK)
-                       noretry = 1;
-       }
-#endif
 
- again:
-       page = dma_alloc_pages(dev,
-               noretry ? gfp | __GFP_NORETRY : gfp, get_order(size));
-       if (page == NULL)
-               return NULL;
-
-       {
-               int high, mmu;
-               bus = page_to_phys(page);
-               memory = page_address(page);
-               high = (bus + size) >= dma_mask;
-               mmu = high;
-               if (force_iommu && !(gfp & GFP_DMA))
-                       mmu = 1;
-               else if (high) {
-                       free_pages((unsigned long)memory,
-                                  get_order(size));
-
-                       /* Don't use the 16MB ZONE_DMA unless absolutely
-                          needed. It's better to use remapping first. */
-                       if (dma_mask < DMA_32BIT_MASK && !(gfp & GFP_DMA)) {
-                               gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
-                               goto again;
-                       }
-
-                       /* Let low level make its own zone decisions */
-                       gfp &= ~(GFP_DMA32|GFP_DMA);
-
-                       if (ops->alloc_coherent)
-                               return ops->alloc_coherent(dev, size,
-                                                          dma_handle, gfp);
-                       return NULL;
-               }
-
-               memset(memory, 0, size);
-               if (!mmu) {
-                       *dma_handle = bus;
-                       return memory;
-               }
-       }
-
-       if (ops->alloc_coherent) {
-               free_pages((unsigned long)memory, get_order(size));
-               gfp &= ~(GFP_DMA|GFP_DMA32);
-               return ops->alloc_coherent(dev, size, dma_handle, gfp);
-       }
-
-       if (ops->map_simple) {
-               *dma_handle = ops->map_simple(dev, virt_to_phys(memory),
-                                             size,
-                                             PCI_DMA_BIDIRECTIONAL);
-               if (*dma_handle != bad_dma_address)
-                       return memory;
-       }
-
-       if (panic_on_overflow)
-               panic("dma_alloc_coherent: IOMMU overflow by %lu bytes\n",
-                     (unsigned long)size);
-       free_pages((unsigned long)memory, get_order(size));
+       if (ops->alloc_coherent)
+               return ops->alloc_coherent(dev, size,
+                               dma_handle, gfp);
        return NULL;
 }
 EXPORT_SYMBOL(dma_alloc_coherent);
@@ -368,17 +271,17 @@ EXPORT_SYMBOL(dma_alloc_coherent);
  * The caller must ensure that the device has finished accessing the mapping.
  */
 void dma_free_coherent(struct device *dev, size_t size,
-                        void *vaddr, dma_addr_t bus)
+                      void *vaddr, dma_addr_t bus)
 {
        struct dma_mapping_ops *ops = get_dma_ops(dev);
 
-       int order = get_order(size);
-       WARN_ON(irqs_disabled());       /* for portability */
-       if (dma_release_from_coherent(dev, order, vaddr))
+       WARN_ON(irqs_disabled());       /* for portability */
+
+       if (dma_release_from_coherent(dev, get_order(size), vaddr))
                return;
-       if (ops->unmap_single)
-               ops->unmap_single(dev, bus, size, 0);
-       free_pages((unsigned long)vaddr, order);
+
+       if (ops->free_coherent)
+               ops->free_coherent(dev, size, vaddr, bus);
 }
 EXPORT_SYMBOL(dma_free_coherent);