Merge v7.1.5linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 8 insertions, 4 deletions

diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index e998dfbd6960..0425d452d41e 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -224,13 +224,17 @@ struct iommu_ioas_map {
  * @size: sizeof(struct iommu_ioas_map_file)
  * @flags: same as for iommu_ioas_map
  * @ioas_id: same as for iommu_ioas_map
- * @fd: the memfd to map
- * @start: byte offset from start of file to map from
+ * @fd: the memfd or supported dma-buf file to map
+ * @start: byte offset from start of the file to map from
  * @length: same as for iommu_ioas_map
  * @iova: same as for iommu_ioas_map
  *
- * Set an IOVA mapping from a memfd file.  All other arguments and semantics
- * match those of IOMMU_IOAS_MAP.
+ * Set an IOVA mapping from a memfd file. On kernels with dma-buf support,
+ * supported dma-buf files may also be accepted. This is not a generic
+ * dma-buf import path; currently supported dma-bufs include single-range
+ * VFIO PCI dma-bufs exported through VFIO_DEVICE_FEATURE_DMA_BUF, and
+ * other dma-bufs may be rejected. All other arguments and semantics match
+ * those of IOMMU_IOAS_MAP.
  */
 struct iommu_ioas_map_file {
 	__u32 size;