mmap the dmabuf with the gem memory at every tbm_bo.

The vc4 backend has to mmap the dmabuf with the gem handle.
Otherwise, when this dmabuf has been exported to another process,
the process cannot call DRM_IOCTL_MODE_MAP_DUMB with the gem handle
which is imported by dmabuf fd.

Change-Id: Ia96340e72a15e5abe1bf2a72cb6230990cfba32c

1 files changed, 41 insertions, 17 deletions

diff --git a/src/tbm_backend_vc4.c b/src/tbm_backend_vc4.c
index d2f9587..eaaedca 100644
--- a/src/tbm_backend_vc4.c
+++ b/src/tbm_backend_vc4.c
@@ -807,6 +807,32 @@ _get_render_node(void)
 }
 #endif
 
+static int
+_bo_mmap(tbm_vc4_bo *bo_data)
+{
+	struct drm_mode_map_dumb arg = {0,};
+	void *map = NULL;
+
+	if (bo_data->pBase)
+		return 1;
+
+	arg.handle = bo_data->gem;
+	if (drmIoctl(bo_data->fd, DRM_IOCTL_MODE_MAP_DUMB, &arg)) {
+		TBM_BACKEND_ERR("Cannot map_vc4 gem=%d\n", bo_data->gem);
+		return 0;
+	}
+
+	map = mmap(NULL, bo_data->size, PROT_READ | PROT_WRITE, MAP_SHARED,
+			bo_data->fd, arg.offset);
+	if (map == MAP_FAILED) {
+		TBM_BACKEND_ERR("Cannot usrptr gem=%d\n", bo_data->gem);
+		return 0;
+	}
+	bo_data->pBase = map;
+
+	return 1;
+}
+
 static unsigned int
 _get_name(int fd, unsigned int gem)
 {
@@ -834,23 +860,9 @@ _vc4_bo_handle(tbm_vc4_bo *bo_data, int device)
 		bo_handle.u32 = (uint32_t)bo_data->gem;
 		break;
 	case HAL_TBM_DEVICE_CPU:
-		if (!bo_data->pBase) {
-			struct drm_mode_map_dumb arg = {0,};
-			void *map = NULL;
-
-			arg.handle = bo_data->gem;
-			if (drmIoctl(bo_data->fd, DRM_IOCTL_MODE_MAP_DUMB, &arg)) {
-				TBM_BACKEND_ERR("Cannot map_vc4 gem=%d\n", bo_data->gem);
-				return (hal_tbm_bo_handle) NULL;
-			}
-
-			map = mmap(NULL, bo_data->size, PROT_READ | PROT_WRITE, MAP_SHARED,
-				   bo_data->fd, arg.offset);
-			if (map == MAP_FAILED) {
-				TBM_BACKEND_ERR("Cannot usrptr gem=%d\n", bo_data->gem);
-				return (hal_tbm_bo_handle) NULL;
-			}
-			bo_data->pBase = map;
+		if (!_bo_mmap(bo_data)) {
+			TBM_BACKEND_ERR("_bo_mmap() failed.");
+			return (hal_tbm_bo_handle) NULL;
 		}
 		bo_handle.ptr = (void *)bo_data->pBase;
 		break;
@@ -1524,6 +1536,18 @@ tbm_vc4_bufmgr_alloc_bo(hal_tbm_bufmgr *bufmgr, unsigned int size,
 
 	pthread_mutex_init(&bo_data->mutex, NULL);
 
+	// vc4 backend has to mmap the dmabuf with the gem handle.
+	// Otherwise, when this dmabuf has been exported to another process,
+	// the process cannot call DRM_IOCTL_MODE_MAP_DUMB with the gem handle
+	// which is imported by dmabuf fd.
+	if (!_bo_mmap(bo_data)) {
+		TBM_BACKEND_ERR("_bo_mmap() failed.\n");
+		free(bo_data);
+		if (error)
+			*error = HAL_TBM_ERROR_INVALID_OPERATION;
+		return NULL;
+	}
+
 	if (bufmgr_data->use_dma_fence && !bo_data->dmabuf) {
 		struct drm_prime_handle arg = {0, };