1 files changed, 81 insertions, 0 deletions

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 48ab52d052b6..967dfcfa2ad2 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -186,6 +186,87 @@ static __init int iommu_setup(char *p)
 }
 early_param("iommu", iommu_setup);
 
+#ifdef CONFIG_X86_32
+int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+                                dma_addr_t device_addr, size_t size, int flags)
+{
+        void __iomem *mem_base = NULL;
+        int pages = size >> PAGE_SHIFT;
+        int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
+
+        if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
+                goto out;
+        if (!size)
+                goto out;
+        if (dev->dma_mem)
+                goto out;
+
+        /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
+
+        mem_base = ioremap(bus_addr, size);
+        if (!mem_base)
+                goto out;
+
+        dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
+        if (!dev->dma_mem)
+                goto out;
+        dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
+        if (!dev->dma_mem->bitmap)
+                goto free1_out;
+
+        dev->dma_mem->virt_base = mem_base;
+        dev->dma_mem->device_base = device_addr;
+        dev->dma_mem->size = pages;
+        dev->dma_mem->flags = flags;
+
+        if (flags & DMA_MEMORY_MAP)
+                return DMA_MEMORY_MAP;
+
+        return DMA_MEMORY_IO;
+
+ free1_out:
+        kfree(dev->dma_mem);
+ out:
+        if (mem_base)
+                iounmap(mem_base);
+        return 0;
+}
+EXPORT_SYMBOL(dma_declare_coherent_memory);
+
+void dma_release_declared_memory(struct device *dev)
+{
+        struct dma_coherent_mem *mem = dev->dma_mem;
+
+        if (!mem)
+                return;
+        dev->dma_mem = NULL;
+        iounmap(mem->virt_base);
+        kfree(mem->bitmap);
+        kfree(mem);
+}
+EXPORT_SYMBOL(dma_release_declared_memory);
+
+void *dma_mark_declared_memory_occupied(struct device *dev,
+                                        dma_addr_t device_addr, size_t size)
+{
+        struct dma_coherent_mem *mem = dev->dma_mem;
+        int pos, err;
+        int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1);
+
+        pages >>= PAGE_SHIFT;
+
+        if (!mem)
+                return ERR_PTR(-EINVAL);
+
+        pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
+        err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
+        if (err != 0)
+                return ERR_PTR(err);
+        return mem->virt_base + (pos << PAGE_SHIFT);
+}
+EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
+#endif /* CONFIG_X86_32 */
+
 int dma_supported(struct device *dev, u64 mask)
 {
 #ifdef CONFIG_PCI