[PATCH 1/2] libdrm: add functions for render node manipulation

[Ilija Hadzic]

Implement the user-space side of drm_render_node_create
and drm_render_node_remove ioctls. The new functions
are drmCreateRenderNode and drmRemoveRenderNode.

Signed-off-by: Ilija Hadzic <ihadzic at research.bell-labs.com>
---
 include/drm/drm.h      |    2 +
 include/drm/drm_mode.h |   16 +++++++++++++
 xf86drm.c              |   56 ++++++++++++++++++++++++++++++++++++++++++++++++
 xf86drm.h              |    5 ++++
 4 files changed, 79 insertions(+), 0 deletions(-)

diff --git a/include/drm/drm.h b/include/drm/drm.h
index 8adb9d5..d5bb126 100644
--- a/include/drm/drm.h
+++ b/include/drm/drm.h
@@ -639,6 +639,8 @@ struct drm_get_cap {
 #define DRM_IOCTL_GEM_FLINK		DRM_IOWR(0x0a, struct drm_gem_flink)
 #define DRM_IOCTL_GEM_OPEN		DRM_IOWR(0x0b, struct drm_gem_open)
 #define DRM_IOCTL_GET_CAP		DRM_IOWR(0x0c, struct drm_get_cap)
+#define DRM_IOCTL_RENDER_NODE_CREATE    DRM_IOWR(0x0d, struct drm_render_node_create)
+#define DRM_IOCTL_RENDER_NODE_REMOVE    DRM_IOWR(0x0e, struct drm_render_node_remove)
 
 #define DRM_IOCTL_SET_UNIQUE		DRM_IOW( 0x10, struct drm_unique)
 #define DRM_IOCTL_AUTH_MAGIC		DRM_IOW( 0x11, struct drm_auth)
diff --git a/include/drm/drm_mode.h b/include/drm/drm_mode.h
index f36c61a..2998629 100644
--- a/include/drm/drm_mode.h
+++ b/include/drm/drm_mode.h
@@ -437,4 +437,20 @@ struct drm_mode_destroy_dumb {
 	__u32 handle;
 };
 
+/*
+ * render node create and remove functions
+ * if crtc/encoders/connectors all == 0 then gpgpu node
+ */
+struct drm_render_node_create {
+	__u32 node_minor_id;
+	__u32 num_crtc;
+	__u32 num_encoder;
+	__u32 num_connector;
+	__u64 id_list_ptr;
+};
+
+struct drm_render_node_remove {
+	__u32 node_minor_id;
+};
+
 #endif
diff --git a/xf86drm.c b/xf86drm.c
index 7def2b3..af43332 100644
--- a/xf86drm.c
+++ b/xf86drm.c
@@ -2552,3 +2552,59 @@ char *drmGetDeviceNameFromFd(int fd)
 out:
 	return strdup(name);
 }
+
+/**
+ * Create a new render node.
+ *
+ * \param fd file descriptor.
+ * \param minor pointer where to put the minor of the new node.
+ * \param num_crtc number of CRTCs to assign to the new node.
+ * \param num_encoder number of encoders to assign to the new node.
+ * \param num_connector number of connectors to assign to the new node.
+ * \param id_list list of CRTC/encoder/connector IDs.
+ *
+ * \return zero on success, or a negative value on failure.
+ *
+ * \internal
+ * Issues an ioctl to the kernel to create a new render node
+ * and popluates the variable pointed by *minor with the new minor
+ * device number.
+ */
+int drmCreateRenderNode(int fd, int *minor,
+			int num_crtc, int num_encoder, int num_connector,
+			uint32_t *id_list)
+{
+	struct drm_render_node_create node;
+	int r;
+
+	node.num_crtc = num_crtc;
+	node.num_encoder = num_encoder;
+	node.num_connector = num_connector;
+	node.id_list_ptr = (uint64_t)(unsigned long)id_list;
+	r = drmIoctl(fd, DRM_IOCTL_RENDER_NODE_CREATE, &node);
+	if (!r)
+		*minor = node.node_minor_id;
+	return r;
+}
+
+/**
+ * Remove the render node.
+ *
+ * \param fd file descriptor.
+ * \param minor minor device number to remove.
+ *
+ * \return zero on success, or a negative value on failure.
+ *
+ * \internal
+ * Issues an ioctl to the kernel to remove a new render node
+ * identified by the file descriptor and the minor device number.
+ */
+int drmRemoveRenderNode(int fd, int minor)
+{
+	struct drm_render_node_remove node;
+	int r;
+
+	node.node_minor_id = minor;
+	r = drmIoctl(fd, DRM_IOCTL_RENDER_NODE_REMOVE, &node);
+	return r;
+}
diff --git a/xf86drm.h b/xf86drm.h
index 76eb94e..bd5b11e 100644
--- a/xf86drm.h
+++ b/xf86drm.h
@@ -701,6 +701,11 @@ extern void drmMsg(const char *format, ...);
 extern int drmSetMaster(int fd);
 extern int drmDropMaster(int fd);
 
+extern int drmCreateRenderNode(int fd, int *minor,
+			       int num_crtc, int num_encoder, int num_connector,
+			       uint32_t *id_list);
+extern int drmRemoveRenderNode(int fd, int minor);
+
 #define DRM_EVENT_CONTEXT_VERSION 2
 
 typedef struct _drmEventContext {
-- 
1.7.8.5