Some drivers (for example qxl) support neither import nor export of dma-bufs. But you can still use dma-bufs to pass buffer references from one process to another; drm_gem_prime_import() will figure the dma-buf came from the same driver and just takes a reference in that case instead of doing a full export/import.
Right now there is no way for userspace to figure it can do this. Add the new prime capability DRM_PRIME_CAP_LOCAL to indicate that. Set the bit for every driver which has the DRIVER_PRIME feature bit set. Cc: Dave Airlie <[email protected]> Signed-off-by: Gerd Hoffmann <[email protected]> --- include/uapi/drm/drm.h | 1 + drivers/gpu/drm/drm_ioctl.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 236b01a1fabf..b6157d48dc1a 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -632,6 +632,7 @@ struct drm_gem_open { #define DRM_CAP_PRIME 0x5 #define DRM_PRIME_CAP_IMPORT 0x1 #define DRM_PRIME_CAP_EXPORT 0x2 +#define DRM_PRIME_CAP_LOCAL 0x4 #define DRM_CAP_TIMESTAMP_MONOTONIC 0x6 #define DRM_CAP_ASYNC_PAGE_FLIP 0x7 /* diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index d337f161909c..00599758783b 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -241,6 +241,8 @@ static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_ case DRM_CAP_PRIME: req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; + req->value |= (dev->driver->driver_features & DRIVER_PRIME) + ? DRM_PRIME_CAP_LOCAL : 0; return 0; case DRM_CAP_SYNCOBJ: req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ); -- 2.18.1 _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
