On Tue, Apr 1, 2025 at 8:58 AM Rob Clark <robdcl...@gmail.com> wrote:
>
> From: Rob Clark <robdcl...@chromium.org>
>
> 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
> v4: Also handle IMPORT_SYNC_FILE case
> v5: Address comments from Dmitry
> v6: checkpatch.pl nits
>
> Signed-off-by: Rob Clark <robdcl...@chromium.org>
> Reviewed-by: Christian König <christian.koe...@amd.com>
> Reviewed-by: Dmitry Osipenko <dmitry.osipe...@collabora.com>
> ---
> drivers/gpu/drm/drm_syncobj.c | 47 +++++++++++++++++++++++++++--------
> include/uapi/drm/drm.h | 4 +++
> 2 files changed, 41 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
> index 4f2ab8a7b50f..636cd83ca29e 100644
> --- a/drivers/gpu/drm/drm_syncobj.c
> +++ b/drivers/gpu/drm/drm_syncobj.c
> @@ -741,7 +741,7 @@ static int drm_syncobj_fd_to_handle(struct drm_file
> *file_private,
> }
>
> static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
> - int fd, int handle)
> + int fd, int handle, u64 point)
> {
> struct dma_fence *fence = sync_file_get_fence(fd);
> struct drm_syncobj *syncobj;
> @@ -755,14 +755,24 @@ static int drm_syncobj_import_sync_file_fence(struct
> drm_file *file_private,
> return -ENOENT;
> }
>
> - drm_syncobj_replace_fence(syncobj, fence);
> + if (point) {
> + struct dma_fence_chain *chain = dma_fence_chain_alloc();
> +
> + if (!chain)
> + return -ENOMEM;
> +
> + drm_syncobj_add_point(syncobj, chain, fence, point);
> + } else {
> + drm_syncobj_replace_fence(syncobj, fence);
> + }
> +
> dma_fence_put(fence);
> drm_syncobj_put(syncobj);
> return 0;
> }
>
> 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 +782,7 @@ 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 +879,9 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev,
> void *data,
> struct drm_file *file_private)
> {
> struct drm_syncobj_handle *args = data;
> + unsigned int 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 +889,18 @@ 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 & ~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);
> @@ -893,6 +911,9 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev,
> void *data,
> struct drm_file *file_private)
> {
> struct drm_syncobj_handle *args = data;
> + unsigned int valid_flags = DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE |
> +
> DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE;
> + u64 point = 0;
>
> if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
> return -EOPNOTSUPP;
oh, I suppose I should add a check for DRIVER_SYNCOBJ_TIMELINE? I'll
send a v7 a bit later
BR,
-R
> @@ -900,14 +921,20 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev,
> void *data,
> if (args->pad)
> return -EINVAL;
>
> - if (args->flags != 0 &&
> - args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
> + if (args->flags & ~valid_flags)
> return -EINVAL;
>
> + if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE)
> + point = args->point;
> +
> if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
> return drm_syncobj_import_sync_file_fence(file_private,
> args->fd,
> - args->handle);
> + args->handle,
> + point);
> +
> + if (args->point)
> + return -EINVAL;
>
> return drm_syncobj_fd_to_handle(file_private, args->fd,
> &args->handle);
> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
> index 7fba37b94401..e63a71d3c607 100644
> --- a/include/uapi/drm/drm.h
> +++ b/include/uapi/drm/drm.h
> @@ -905,13 +905,17 @@ struct drm_syncobj_destroy {
> };
>
> #define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE (1 << 0)
> +#define DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_TIMELINE (1 << 1)
> #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
>
