On Thursday, November 16, 2017 2:10:54 AM JST, Gustavo Padovan wrote:
From: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
Add a videobuf2-fence.h header file that contains different helpers
for DMA buffer sharing explicit fence support in videobuf2.
v2: - use fence context provided by the caller in vb2_fence_alloc()
Signed-off-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
---
include/media/videobuf2-fence.h | 48
+++++++++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
create mode 100644 include/media/videobuf2-fence.h
diff --git a/include/media/videobuf2-fence.h
b/include/media/videobuf2-fence.h
new file mode 100644
index 000000000000..b49cc1bf6bb4
--- /dev/null
+++ b/include/media/videobuf2-fence.h
@@ -0,0 +1,48 @@
+/*
+ * videobuf2-fence.h - DMA buffer sharing fence helpers for videobuf 2
+ *
+ * Copyright (C) 2016 Samsung Electronics
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/dma-fence.h>
+#include <linux/slab.h>
+
+static DEFINE_SPINLOCK(vb2_fence_lock);
+
+static inline const char *vb2_fence_get_driver_name(struct
dma_fence *fence)
+{
+ return "vb2_fence";
+}
+
+static inline const char *vb2_fence_get_timeline_name(struct
dma_fence *fence)
+{
+ return "vb2_fence_timeline";
+}
+
+static inline bool vb2_fence_enable_signaling(struct dma_fence *fence)
+{
+ return true;
+}
+
+static const struct dma_fence_ops vb2_fence_ops = {
+ .get_driver_name = vb2_fence_get_driver_name,
+ .get_timeline_name = vb2_fence_get_timeline_name,
+ .enable_signaling = vb2_fence_enable_signaling,
+ .wait = dma_fence_default_wait,
+};
It is probably not a good idea to define that struct here since it will be
deduplicated for every source file that includes it.
Maybe change it to a simple declaration, and move the definition to
videobuf2-core.c or a dedicated videobuf2-fence.c file?
+
+static inline struct dma_fence *vb2_fence_alloc(u64 context)
+{
+ struct dma_fence *vb2_fence = kzalloc(sizeof(*vb2_fence), GFP_KERNEL);
+
+ if (!vb2_fence)
+ return NULL;
+
+ dma_fence_init(vb2_fence, &vb2_fence_ops, &vb2_fence_lock, context, 1);
+
+ return vb2_fence;
+}
Not sure we gain a lot by having this function static inline, but your
call.
