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Diffstat (limited to 'arch/x86/kernel/pci-swiotlb.c')
-rw-r--r--arch/x86/kernel/pci-swiotlb.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
new file mode 100644
index 000000000..77dd0ad58
--- /dev/null
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -0,0 +1,112 @@
+/* Glue code to lib/swiotlb.c */
+
+#include <linux/pci.h>
+#include <linux/cache.h>
+#include <linux/module.h>
+#include <linux/swiotlb.h>
+#include <linux/bootmem.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/iommu.h>
+#include <asm/swiotlb.h>
+#include <asm/dma.h>
+#include <asm/xen/swiotlb-xen.h>
+#include <asm/iommu_table.h>
+int swiotlb __read_mostly;
+
+void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags,
+ struct dma_attrs *attrs)
+{
+ void *vaddr;
+
+ vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags,
+ attrs);
+ if (vaddr)
+ return vaddr;
+
+ return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
+}
+
+void x86_swiotlb_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_addr,
+ struct dma_attrs *attrs)
+{
+ if (is_swiotlb_buffer(dma_to_phys(dev, dma_addr)))
+ swiotlb_free_coherent(dev, size, vaddr, dma_addr);
+ else
+ dma_generic_free_coherent(dev, size, vaddr, dma_addr, attrs);
+}
+
+static struct dma_map_ops swiotlb_dma_ops = {
+ .mapping_error = swiotlb_dma_mapping_error,
+ .alloc = x86_swiotlb_alloc_coherent,
+ .free = x86_swiotlb_free_coherent,
+ .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
+ .sync_single_for_device = swiotlb_sync_single_for_device,
+ .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
+ .sync_sg_for_device = swiotlb_sync_sg_for_device,
+ .map_sg = swiotlb_map_sg_attrs,
+ .unmap_sg = swiotlb_unmap_sg_attrs,
+ .map_page = swiotlb_map_page,
+ .unmap_page = swiotlb_unmap_page,
+ .dma_supported = NULL,
+};
+
+/*
+ * pci_swiotlb_detect_override - set swiotlb to 1 if necessary
+ *
+ * This returns non-zero if we are forced to use swiotlb (by the boot
+ * option).
+ */
+int __init pci_swiotlb_detect_override(void)
+{
+ int use_swiotlb = swiotlb | swiotlb_force;
+
+ if (swiotlb_force)
+ swiotlb = 1;
+
+ return use_swiotlb;
+}
+IOMMU_INIT_FINISH(pci_swiotlb_detect_override,
+ pci_xen_swiotlb_detect,
+ pci_swiotlb_init,
+ pci_swiotlb_late_init);
+
+/*
+ * if 4GB or more detected (and iommu=off not set) return 1
+ * and set swiotlb to 1.
+ */
+int __init pci_swiotlb_detect_4gb(void)
+{
+ /* don't initialize swiotlb if iommu=off (no_iommu=1) */
+#ifdef CONFIG_X86_64
+ if (!no_iommu && max_pfn > MAX_DMA32_PFN)
+ swiotlb = 1;
+#endif
+ return swiotlb;
+}
+IOMMU_INIT(pci_swiotlb_detect_4gb,
+ pci_swiotlb_detect_override,
+ pci_swiotlb_init,
+ pci_swiotlb_late_init);
+
+void __init pci_swiotlb_init(void)
+{
+ if (swiotlb) {
+ swiotlb_init(0);
+ dma_ops = &swiotlb_dma_ops;
+ }
+}
+
+void __init pci_swiotlb_late_init(void)
+{
+ /* An IOMMU turned us off. */
+ if (!swiotlb)
+ swiotlb_free();
+ else {
+ printk(KERN_INFO "PCI-DMA: "
+ "Using software bounce buffering for IO (SWIOTLB)\n");
+ swiotlb_print_info();
+ }
+}