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>

1 files changed, 12 insertions, 109 deletions

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 87d4d6964ec2..613332b26e31 100644
--- 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);