--- /dev/null
+/*
+ * Dynamic DMA mapping support.
+ *
+ * On i386 there is no hardware dynamic DMA address translation,
+ * so consistent alloc/free are merely page allocation/freeing.
+ * The rest of the dynamic DMA mapping interface is implemented
+ * in asm/pci.h.
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <asm/io.h>
+#include <xen/balloon.h>
+#include <asm/tlbflush.h>
+#include <asm-i386/mach-xen/asm/swiotlb.h>
+#include <asm/bug.h>
+
+#ifdef __x86_64__
+int iommu_merge __read_mostly = 0;
+EXPORT_SYMBOL(iommu_merge);
+
+dma_addr_t bad_dma_address __read_mostly;
+EXPORT_SYMBOL(bad_dma_address);
+
+/* This tells the BIO block layer to assume merging. Default to off
+ because we cannot guarantee merging later. */
+int iommu_bio_merge __read_mostly = 0;
+EXPORT_SYMBOL(iommu_bio_merge);
+
+__init int iommu_setup(char *p)
+{
+ return 1;
+}
+#endif
+
+struct dma_coherent_mem {
+ void *virt_base;
+ u32 device_base;
+ int size;
+ int flags;
+ unsigned long *bitmap;
+};
+
+#define IOMMU_BUG_ON(test) \
+do { \
+ if (unlikely(test)) { \
+ printk(KERN_ALERT "Fatal DMA error! " \
+ "Please use 'swiotlb=force'\n"); \
+ BUG(); \
+ } \
+} while (0)
+
+int
+dma_map_sg(struct device *hwdev, struct scatterlist *sg, int nents,
+ enum dma_data_direction direction)
+{
+ int i, rc;
+
+ if (direction == DMA_NONE)
+ BUG();
+ WARN_ON(nents == 0 || sg[0].length == 0);
+
+ if (swiotlb) {
+ rc = swiotlb_map_sg(hwdev, sg, nents, direction);
+ } else {
+ for (i = 0; i < nents; i++ ) {
+ sg[i].dma_address =
+ page_to_bus(sg[i].page) + sg[i].offset;
+ sg[i].dma_length = sg[i].length;
+ BUG_ON(!sg[i].page);
+ IOMMU_BUG_ON(address_needs_mapping(
+ hwdev, sg[i].dma_address));
+ }
+ rc = nents;
+ }
+
+ flush_write_buffers();
+ return rc;
+}
+EXPORT_SYMBOL(dma_map_sg);
+
+void
+dma_unmap_sg(struct device *hwdev, struct scatterlist *sg, int nents,
+ enum dma_data_direction direction)
+{
+ BUG_ON(direction == DMA_NONE);
+ if (swiotlb)
+ swiotlb_unmap_sg(hwdev, sg, nents, direction);
+}
+EXPORT_SYMBOL(dma_unmap_sg);
+
+/*
+ * XXX This file is also used by xenLinux/ia64.
+ * "defined(__i386__) || defined (__x86_64__)" means "!defined(__ia64__)".
+ * This #if work around should be removed once this file is merbed back into
+ * i386' pci-dma or is moved to drivers/xen/core.
+ */
+#if defined(__i386__) || defined(__x86_64__)
+dma_addr_t
+dma_map_page(struct device *dev, struct page *page, unsigned long offset,
+ size_t size, enum dma_data_direction direction)
+{
+ dma_addr_t dma_addr;
+
+ BUG_ON(direction == DMA_NONE);
+
+ if (swiotlb) {
+ dma_addr = swiotlb_map_page(
+ dev, page, offset, size, direction);
+ } else {
+ dma_addr = page_to_bus(page) + offset;
+ IOMMU_BUG_ON(address_needs_mapping(dev, dma_addr));
+ }
+
+ return dma_addr;
+}
+EXPORT_SYMBOL(dma_map_page);
+
+void
+dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
+ enum dma_data_direction direction)
+{
+ BUG_ON(direction == DMA_NONE);
+ if (swiotlb)
+ swiotlb_unmap_page(dev, dma_address, size, direction);
+}
+EXPORT_SYMBOL(dma_unmap_page);
+#endif /* defined(__i386__) || defined(__x86_64__) */
+
+int
+dma_mapping_error(dma_addr_t dma_addr)
+{
+ if (swiotlb)
+ return swiotlb_dma_mapping_error(dma_addr);
+ return 0;
+}
+EXPORT_SYMBOL(dma_mapping_error);
+
+int
+dma_supported(struct device *dev, u64 mask)
+{
+ if (swiotlb)
+ return swiotlb_dma_supported(dev, mask);
+ /*
+ * By default we'll BUG when an infeasible DMA is requested, and
+ * request swiotlb=force (see IOMMU_BUG_ON).
+ */
+ return 1;
+}
+EXPORT_SYMBOL(dma_supported);
+
+void *dma_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp)
+{
+ void *ret;
+ struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
+ unsigned int order = get_order(size);
+ unsigned long vstart;
+ /* ignore region specifiers */
+ gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
+
+ if (mem) {
+ int page = bitmap_find_free_region(mem->bitmap, mem->size,
+ order);
+ if (page >= 0) {
+ *dma_handle = mem->device_base + (page << PAGE_SHIFT);
+ ret = mem->virt_base + (page << PAGE_SHIFT);
+ memset(ret, 0, size);
+ return ret;
+ }
+ if (mem->flags & DMA_MEMORY_EXCLUSIVE)
+ return NULL;
+ }
+
+ if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
+ gfp |= GFP_DMA;
+
+ vstart = __get_free_pages(gfp, order);
+ ret = (void *)vstart;
+
+ if (ret != NULL) {
+ /* NB. Hardcode 31 address bits for now: aacraid limitation. */
+ if (xen_create_contiguous_region(vstart, order, 31) != 0) {
+ free_pages(vstart, order);
+ return NULL;
+ }
+ memset(ret, 0, size);
+ *dma_handle = virt_to_bus(ret);
+ }
+ return ret;
+}
+EXPORT_SYMBOL(dma_alloc_coherent);
+
+void dma_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle)
+{
+ struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
+ int order = get_order(size);
+
+ if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+ int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
+
+ bitmap_release_region(mem->bitmap, page, order);
+ } else {
+ xen_destroy_contiguous_region((unsigned long)vaddr, order);
+ free_pages((unsigned long)vaddr, order);
+ }
+}
+EXPORT_SYMBOL(dma_free_coherent);
+
+#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
+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;
+ int pages = size >> PAGE_SHIFT;
+ int bitmap_size = (pages + 31)/32;
+
+ 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 = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
+ if (!dev->dma_mem)
+ goto out;
+ memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
+ dev->dma_mem->bitmap = kmalloc(bitmap_size, GFP_KERNEL);
+ if (!dev->dma_mem->bitmap)
+ goto free1_out;
+ memset(dev->dma_mem->bitmap, 0, bitmap_size);
+
+ 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->bitmap);
+ out:
+ 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 pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ int pos, err;
+
+ 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 /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
+
+dma_addr_t
+dma_map_single(struct device *dev, void *ptr, size_t size,
+ enum dma_data_direction direction)
+{
+ dma_addr_t dma;
+
+ if (direction == DMA_NONE)
+ BUG();
+ WARN_ON(size == 0);
+
+ if (swiotlb) {
+ dma = swiotlb_map_single(dev, ptr, size, direction);
+ } else {
+ dma = virt_to_bus(ptr);
+ IOMMU_BUG_ON(range_straddles_page_boundary(ptr, size));
+ IOMMU_BUG_ON(address_needs_mapping(dev, dma));
+ }
+
+ flush_write_buffers();
+ return dma;
+}
+EXPORT_SYMBOL(dma_map_single);
+
+void
+dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
+ enum dma_data_direction direction)
+{
+ if (direction == DMA_NONE)
+ BUG();
+ if (swiotlb)
+ swiotlb_unmap_single(dev, dma_addr, size, direction);
+}
+EXPORT_SYMBOL(dma_unmap_single);
+
+void
+dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size,
+ enum dma_data_direction direction)
+{
+ if (swiotlb)
+ swiotlb_sync_single_for_cpu(dev, dma_handle, size, direction);
+}
+EXPORT_SYMBOL(dma_sync_single_for_cpu);
+
+void
+dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, size_t size,
+ enum dma_data_direction direction)
+{
+ if (swiotlb)
+ swiotlb_sync_single_for_device(dev, dma_handle, size, direction);
+}
+EXPORT_SYMBOL(dma_sync_single_for_device);
git://git.onelab.eu / linux-2.6.git / blobdiff