[PATCH 07/12] drm/syncobj: add drm_syncobj_timeline_signal

From: Julian Orth

Date: Sat May 16 2026 - 07:10:08 EST


This makes the logic from drm_syncobj_timeline_signal_ioctl available to
callers that already have an array of drm_syncobj.

Signed-off-by: Julian Orth <ju.orth@xxxxxxxxx>
---
drivers/gpu/drm/drm_syncobj.c | 50 ++++++++++++++++++++++++++++++++-----------
include/drm/drm_syncobj.h | 2 ++
2 files changed, 40 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 8ccfbd972191..948084f56c32 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -1675,9 +1675,6 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
{
struct drm_syncobj_timeline_array *args = data;
struct drm_syncobj **syncobjs;
- struct dma_fence_chain **chains;
- uint64_t *points;
- uint32_t i, j;
int ret;

if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
@@ -1696,26 +1693,55 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
if (ret < 0)
return ret;

- points = kmalloc_array(args->count_handles, sizeof(*points),
+ ret = drm_syncobj_timeline_signal(syncobjs, args->points, args->count_handles);
+
+ drm_syncobj_array_free(syncobjs, args->count_handles);
+
+ return ret;
+}
+
+/**
+ * drm_syncobj_timeline_signal - signal timeline points on syncobjs
+ * @syncobjs: array of syncobjs
+ * @user_points: user pointer to array of timeline points
+ * @count: number of syncobjs
+ *
+ * Signals each syncobj at the corresponding timeline point.
+ *
+ * Returns 0 on success or a negative error value on failure.
+ */
+int
+drm_syncobj_timeline_signal(struct drm_syncobj **syncobjs,
+ u64 user_points, u32 count)
+{
+ struct dma_fence_chain **chains;
+ uint64_t *points;
+ uint32_t i, j;
+ int ret = 0;
+
+ if (count == 0)
+ return -EINVAL;
+
+ points = kmalloc_array(count, sizeof(*points),
GFP_KERNEL);
if (!points) {
ret = -ENOMEM;
goto out;
}
- if (!u64_to_user_ptr(args->points)) {
- memset(points, 0, args->count_handles * sizeof(uint64_t));
- } else if (copy_from_user(points, u64_to_user_ptr(args->points),
- sizeof(uint64_t) * args->count_handles)) {
+ if (!u64_to_user_ptr(user_points)) {
+ memset(points, 0, count * sizeof(uint64_t));
+ } else if (copy_from_user(points, u64_to_user_ptr(user_points),
+ sizeof(uint64_t) * count)) {
ret = -EFAULT;
goto err_points;
}

- chains = kmalloc_array(args->count_handles, sizeof(void *), GFP_KERNEL);
+ chains = kmalloc_array(count, sizeof(void *), GFP_KERNEL);
if (!chains) {
ret = -ENOMEM;
goto err_points;
}
- for (i = 0; i < args->count_handles; i++) {
+ for (i = 0; i < count; i++) {
chains[i] = dma_fence_chain_alloc();
if (!chains[i]) {
for (j = 0; j < i; j++)
@@ -1725,7 +1751,7 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
}
}

- for (i = 0; i < args->count_handles; i++) {
+ for (i = 0; i < count; i++) {
struct dma_fence *fence = dma_fence_get_stub();

drm_syncobj_add_point(syncobjs[i], chains[i],
@@ -1737,10 +1763,10 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
err_points:
kfree(points);
out:
- drm_syncobj_array_free(syncobjs, args->count_handles);

return ret;
}
+EXPORT_SYMBOL(drm_syncobj_timeline_signal);

int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_private)
diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h
index ec8042d61466..a9216ea07946 100644
--- a/include/drm/drm_syncobj.h
+++ b/include/drm/drm_syncobj.h
@@ -139,6 +139,8 @@ int drm_syncobj_register_eventfd(struct drm_syncobj *syncobj,
int drm_syncobj_transfer(struct drm_syncobj *src, u64 src_point,
struct drm_syncobj *dst, u64 dst_point,
u32 flags);
+int drm_syncobj_timeline_signal(struct drm_syncobj **syncobjs,
+ u64 user_points, u32 count);
void drm_syncobj_free(struct kref *kref);
int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
struct dma_fence *fence);

--
2.54.0