vfio: option to unmap all

For the UNMAP_DMA ioctl, delete all mappings if VFIO_DMA_UNMAP_FLAG_ALL
is set.  Define the corresponding VFIO_UNMAP_ALL extension.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index d181277..7846259 100644 (file)
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -46,6 +46,9 @@
  */
 #define VFIO_NOIOMMU_IOMMU             8
 
+/* Supports VFIO_DMA_UNMAP_FLAG_ALL */
+#define VFIO_UNMAP_ALL                 9
+
 /*
  * The IOCTL interface is designed for extensibility by embedding the
  * structure length (argsz) and flags into structures passed between
@@ -1102,6 +1105,7 @@ struct vfio_bitmap {
  * field.  No guarantee is made to the user that arbitrary unmaps of iova
  * or size different from those used in the original mapping call will
  * succeed.
+ *
  * VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP should be set to get the dirty bitmap
  * before unmapping IO virtual addresses. When this flag is set, the user must
  * provide a struct vfio_bitmap in data[]. User must provide zero-allocated
@@ -1111,11 +1115,15 @@ struct vfio_bitmap {
  * indicates that the page at that offset from iova is dirty. A Bitmap of the
  * pages in the range of unmapped size is returned in the user-provided
  * vfio_bitmap.data.
+ *
+ * If flags & VFIO_DMA_UNMAP_FLAG_ALL, unmap all addresses.  iova and size
+ * must be 0.  This cannot be combined with the get-dirty-bitmap flag.
  */
 struct vfio_iommu_type1_dma_unmap {
        __u32   argsz;
        __u32   flags;
 #define VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP (1 << 0)
+#define VFIO_DMA_UNMAP_FLAG_ALL                     (1 << 1)
        __u64   iova;                           /* IO virtual address */
        __u64   size;                           /* Size of mapping (bytes) */
        __u8    data[];