uio: introduce UIO_MEM_IOVA

Introduce the concept of mapping physical memory locations that
are normal memory. The new type UIO_MEM_IOVA are similar to
existing UIO_MEM_PHYS but the backing memory is not marked as uncached.

Also, indent related switch to the currently used style.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 14 insertions, 11 deletions

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 0ffb324aa038..e601bd3fbae1 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -738,7 +738,8 @@ static int uio_mmap_physical(struct vm_area_struct *vma)
                 return -EINVAL;
 
         vma->vm_ops = &uio_physical_vm_ops;
-        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+        if (idev->info->mem[mi].memtype == UIO_MEM_PHYS)
+                vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
         /*
          * We cannot use the vm_iomap_memory() helper here,
@@ -795,18 +796,19 @@ static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
         }
 
         switch (idev->info->mem[mi].memtype) {
-                case UIO_MEM_PHYS:
-                        ret = uio_mmap_physical(vma);
-                        break;
-                case UIO_MEM_LOGICAL:
-                case UIO_MEM_VIRTUAL:
-                        ret = uio_mmap_logical(vma);
-                        break;
-                default:
-                        ret = -EINVAL;
+        case UIO_MEM_IOVA:
+        case UIO_MEM_PHYS:
+                ret = uio_mmap_physical(vma);
+                break;
+        case UIO_MEM_LOGICAL:
+        case UIO_MEM_VIRTUAL:
+                ret = uio_mmap_logical(vma);
+                break;
+        default:
+                ret = -EINVAL;
         }
 
-out:
+ out:
         mutex_unlock(&idev->info_lock);
         return ret;
 }
diff --git a/include/linux/uio_driver.h b/include/linux/uio_driver.h
index 6f8b68cd460f..a3cd7cb67a69 100644
--- a/include/linux/uio_driver.h
+++ b/include/linux/uio_driver.h
@@ -133,6 +133,7 @@ extern void uio_event_notify(struct uio_info *info);
 #define UIO_MEM_PHYS    1
 #define UIO_MEM_LOGICAL 2
 #define UIO_MEM_VIRTUAL 3
+#define UIO_MEM_IOVA    4
 
 /* defines for uio_port->porttype */
 #define UIO_PORT_NONE   0