[Qemu-devel] [RFC v2 1/4] Add EXEC_FLAG to VFIO DMA mappings

[Alvise Rigo <a.rigo@virtualopensystems.com>]

The flag is mandatory for the ARM SMMU so we always add it if the MMIO
handles it.

Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
---
 hw/vfio/common.c           | 9 +++++++++
 hw/vfio/vfio-common.h      | 1 +
 linux-headers/linux/vfio.h | 2 ++
 3 files changed, 12 insertions(+)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 9d1f723..a805c5d 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -107,6 +107,11 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr iova,
         map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
     }
 
+    /* add exec flag */
+    if (container->iommu_data.has_exec_cap) {
+        map.flags |= VFIO_DMA_MAP_FLAG_EXEC;
+    }
+
     /*
      * Try the mapping, if it fails with EBUSY, unmap the region and try
      * again.  This shouldn't be necessary, but we sometimes see it in
@@ -352,6 +357,10 @@ static int vfio_connect_container(VFIOGroup *group)
             return -errno;
         }
 
+        if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_IOMMU_PROT_EXEC)) {
+            container->iommu_data.has_exec_cap = true;
+        }
+
         container->iommu_data.type1.listener = vfio_memory_listener;
         container->iommu_data.release = vfio_listener_release;
 
diff --git a/hw/vfio/vfio-common.h b/hw/vfio/vfio-common.h
index 21148ef..1abbd1a 100644
--- a/hw/vfio/vfio-common.h
+++ b/hw/vfio/vfio-common.h
@@ -35,6 +35,7 @@ typedef struct VFIOContainer {
         union {
             VFIOType1 type1;
         };
+        bool has_exec_cap; /* support of exec capability by the IOMMU */
         void (*release)(struct VFIOContainer *);
     } iommu_data;
     QLIST_HEAD(, VFIOGroup) group_list;
diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h
index 17c58e0..95a02c5 100644
--- a/linux-headers/linux/vfio.h
+++ b/linux-headers/linux/vfio.h
@@ -24,6 +24,7 @@
 #define VFIO_TYPE1_IOMMU		1
 #define VFIO_SPAPR_TCE_IOMMU		2
 
+#define VFIO_IOMMU_PROT_EXEC		5
 /*
  * The IOCTL interface is designed for extensibility by embedding the
  * structure length (argsz) and flags into structures passed between
@@ -392,6 +393,7 @@ struct vfio_iommu_type1_dma_map {
 	__u32	flags;
 #define VFIO_DMA_MAP_FLAG_READ (1 << 0)		/* readable from device */
 #define VFIO_DMA_MAP_FLAG_WRITE (1 << 1)	/* writable from device */
+#define VFIO_DMA_MAP_FLAG_EXEC (1 << 2)	/* executable from device */
 	__u64	vaddr;				/* Process virtual address */
 	__u64	iova;				/* IO virtual address */
 	__u64	size;				/* Size of mapping (bytes) */
-- 
1.9.1