x86: ---
 drivers/pci/pci-sysfs.c  |   64 +++++++++++++++++++++++++++++++++++++++++++++++
 include/asm-i386/pci.h   |    1 
 include/asm-x86_64/pci.h |    1 
 include/linux/pci.h      |    4 ++
 4 files changed, 69 insertions(+), 1 deletion(-)

Index: linux/drivers/pci/pci-sysfs.c
===================================================================
--- linux.orig/drivers/pci/pci-sysfs.c
+++ linux/drivers/pci/pci-sysfs.c
@@ -384,6 +384,49 @@ pci_mmap_resource(struct kobject *kobj, 
 	return pci_mmap_page_range(pdev, vma, mmap_type, 0);
 }
 
+#ifdef HAVE_PCI_COHERENT_MMAP
+
+struct coh_mmap_data {
+	void *map;
+	struct device *dev;
+	dma_addr_t busadr;
+};
+
+void pci_coherent_mmap_close(struct vm_area_struct *vma)
+{
+	struct coh_mmap_data *cm = vma->vm_private_data;
+	dma_free_coherent(cm->dev, vma->vm_end - vma->vm_start, cm->map,
+			  cm->busadr);
+}
+
+static struct vm_operations_struct pci_coherent_vmops = {
+	.close = pci_coherent_mmap_close,
+};
+
+static int
+pci_mmap_coherent_mem(struct kobject *kobj, struct bin_attribute *attr,
+		  struct vm_area_struct *vma)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct coh_mmap_data *cm = kmalloc(sizeof(struct coh_mmap_data),
+					   GFP_KERNEL);
+	if (!cm)
+		return -ENOMEM;
+	cm->map = dma_alloc_coherent(dev, vma->vm_end - vma->vm_start,
+				     &cm->busadr, GFP_KERNEL);
+	cm->dev = dev;
+	if (!cm->map) {
+		kfree(cm->map);
+		return -ENOMEM;
+	}
+	vma->vm_private_data = cm;
+	vma->vm_pgoff = cm->busadr >> PAGE_SHIFT;
+	vma->vm_ops = &pci_coherent_vmops;
+	return pci_mmap_page_range(pdev, vma, pci_mmap_coherent, 0);
+}
+#endif
+
 /**
  * pci_create_resource_files - create resource files in sysfs for @dev
  * @dev: dev in question
@@ -419,6 +462,22 @@ pci_create_resource_files(struct pci_dev
 			sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
 		}
 	}
+#ifdef HAVE_PCI_COHERENT_MMAP
+	{
+		struct bin_attribute *a = kzalloc(sizeof(struct bin_attribute),
+						  GFP_KERNEL);
+		if (!a)
+			return;
+		pdev->coherent_attr = a;
+		a->attr.name = "coherent_mem";
+		a->attr.mode = S_IRUSR | S_IWUSR;
+		a->attr.owner = THIS_MODULE;
+		a->size = *(pdev->dev.dma_mask);
+		a->mmap = pci_mmap_coherent_mem;
+		a->private = NULL;
+		sysfs_create_bin_file(&pdev->dev.kobj, a);
+	}
+#endif
 }
 
 /**
@@ -442,6 +501,11 @@ pci_remove_resource_files(struct pci_dev
 			kfree(res_attr);
 		}
 	}
+
+#ifdef HAVE_PCI_COHERENT_MMAP
+	sysfs_remove_bin_file(&pdev->dev.kobj, pdev->coherent_attr);
+	kfree(pdev->coherent_attr);
+#endif
 }
 #else /* !HAVE_PCI_MMAP */
 static inline void pci_create_resource_files(struct pci_dev *dev) { return; }
Index: linux/include/linux/pci.h
===================================================================
--- linux.orig/include/linux/pci.h
+++ linux/include/linux/pci.h
@@ -55,7 +55,8 @@
 /* File state for mmap()s on /proc/bus/pci/X/Y */
 enum pci_mmap_state {
 	pci_mmap_io,
-	pci_mmap_mem
+	pci_mmap_mem,
+	pci_mmap_coherent
 };
 
 /* This defines the direction arg to the DMA mapping routines. */
@@ -172,6 +173,7 @@ struct pci_dev {
 	struct bin_attribute *rom_attr; /* attribute descriptor for sysfs ROM entry */
 	int rom_attr_enabled;		/* has display of the rom attribute been enabled? */
 	struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */
+	struct bin_attribute *coherent_attr;
 };
 
 #define pci_dev_g(n) list_entry(n, struct pci_dev, global_list)
Index: linux/include/asm-i386/pci.h
===================================================================
--- linux.orig/include/asm-i386/pci.h
+++ linux/include/asm-i386/pci.h
@@ -90,6 +90,7 @@ pci_dac_dma_sync_single_for_device(struc
 }
 
 #define HAVE_PCI_MMAP
+#define HAVE_PCI_COHERENT_MMAP
 extern int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 			       enum pci_mmap_state mmap_state, int write_combine);
 
Index: linux/include/asm-x86_64/pci.h
===================================================================
--- linux.orig/include/asm-x86_64/pci.h
+++ linux/include/asm-x86_64/pci.h
@@ -132,6 +132,7 @@ static inline void pci_dma_burst_advice(
 #endif
 
 #define HAVE_PCI_MMAP
+#define HAVE_PCI_COHERENT_MMAP
 extern int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 			       enum pci_mmap_state mmap_state, int write_combine);