[PATCH v3] drm/syncobj: Extend EXPORT_SYNC_FILE for timeline syncobjs
From: Rob Clark
Date: Thu Mar 27 2025 - 12:36:34 EST
From: Rob Clark <robdclark@xxxxxxxxxxxx>
Add support for exporting a dma_fence fd for a specific point on a
timeline. This is needed for vtest/vpipe[1][2] to implement timeline
syncobj support, as it needs a way to turn a point on a timeline back
into a dma_fence fd. It also closes an odd omission from the syncobj
UAPI.
[1] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33433
[2] https://gitlab.freedesktop.org/virgl/virglrenderer/-/merge_requests/805
v2: Add DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE
v3: Add unstaged uabi header hunk
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/drm_syncobj.c | 18 +++++++++++++-----
include/uapi/drm/drm.h | 3 +++
2 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 4f2ab8a7b50f..bc57d6f1a22e 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -762,7 +762,7 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
}
static int drm_syncobj_export_sync_file(struct drm_file *file_private,
- int handle, int *p_fd)
+ int handle, u64 point, int *p_fd)
{
int ret;
struct dma_fence *fence;
@@ -772,7 +772,7 @@ static int drm_syncobj_export_sync_file(struct drm_file *file_private,
if (fd < 0)
return fd;
- ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence);
+ ret = drm_syncobj_find_fence(file_private, handle, point, 0, &fence);
if (ret)
goto err_put_fd;
@@ -869,6 +869,9 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_private)
{
struct drm_syncobj_handle *args = data;
+ unsigned valid_flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE |
+ DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE;
+ u64 point = 0;
if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
return -EOPNOTSUPP;
@@ -876,13 +879,18 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
if (args->pad)
return -EINVAL;
- if (args->flags != 0 &&
- args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
+ if (args->flags != 0 && (args->flags & ~valid_flags))
return -EINVAL;
+ if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE)
+ point = args->point;
+
if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
return drm_syncobj_export_sync_file(file_private, args->handle,
- &args->fd);
+ point, &args->fd);
+
+ if (args->point)
+ return -EINVAL;
return drm_syncobj_handle_to_fd(file_private, args->handle,
&args->fd);
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 7fba37b94401..dd0fd13eadbd 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -906,12 +906,15 @@ struct drm_syncobj_destroy {
#define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE (1 << 0)
#define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE (1 << 0)
+#define DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE (1 << 1)
struct drm_syncobj_handle {
__u32 handle;
__u32 flags;
__s32 fd;
__u32 pad;
+
+ __u64 point;
};
struct drm_syncobj_transfer {
--
2.49.0