console: add support for dmabufs

This patch adds support for dma-bufs to the qemu console interfaces.
It adds a new "struct QemuDmaBuf" to represent a dmabuf with accociated
metatdata (size, format).  It adds three functions (and
DisplayChangeListenerOps operations) to set a dma-buf as display
scanout, as cursor and to release a dmabuf.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20171010135453.6704-2-kraxel@redhat.com

include/qemu/typedefs.h

@@ -83,6 +83,7 @@ typedef struct PropertyInfo PropertyInfo;
 typedef struct PS2State PS2State;
 typedef struct QEMUBH QEMUBH;
 typedef struct QemuConsole QemuConsole;
+typedef struct QemuDmaBuf QemuDmaBuf;
 typedef struct QEMUFile QEMUFile;
 typedef struct QemuOpt QemuOpt;
 typedef struct QemuOpts QemuOpts;

include/ui/console.h

@@ -5,6 +5,7 @@
 #include "qom/object.h"
 #include "qapi/qmp/qdict.h"
 #include "qemu/notify.h"
+#include "qemu/typedefs.h"
 #include "qapi-types.h"
 #include "qemu/error-report.h"
 #include "qapi/error.h"
@@ -180,6 +181,15 @@ struct QEMUGLParams {
     int minor_ver;
 };
 
+struct QemuDmaBuf {
+    int       fd;
+    uint32_t  width;
+    uint32_t  height;
+    uint32_t  stride;
+    uint32_t  fourcc;
+    uint32_t  texture;
+};
+
 typedef struct DisplayChangeListenerOps {
     const char *dpy_name;
 
@@ -220,6 +230,13 @@ typedef struct DisplayChangeListenerOps {
                                    uint32_t backing_height,
                                    uint32_t x, uint32_t y,
                                    uint32_t w, uint32_t h);
+    void (*dpy_gl_scanout_dmabuf)(DisplayChangeListener *dcl,
+                                  QemuDmaBuf *dmabuf);
+    void (*dpy_gl_cursor_dmabuf)(DisplayChangeListener *dcl,
+                                 QemuDmaBuf *dmabuf,
+                                 uint32_t pos_x, uint32_t pos_y);
+    void (*dpy_gl_release_dmabuf)(DisplayChangeListener *dcl,
+                                  QemuDmaBuf *dmabuf);
     void (*dpy_gl_update)(DisplayChangeListener *dcl,
                           uint32_t x, uint32_t y, uint32_t w, uint32_t h);
 
@@ -288,6 +305,13 @@ void dpy_gl_scanout_texture(QemuConsole *con,
                             uint32_t backing_id, bool backing_y_0_top,
                             uint32_t backing_width, uint32_t backing_height,
                             uint32_t x, uint32_t y, uint32_t w, uint32_t h);
+void dpy_gl_scanout_dmabuf(QemuConsole *con,
+                           QemuDmaBuf *dmabuf);
+void dpy_gl_cursor_dmabuf(QemuConsole *con,
+                          QemuDmaBuf *dmabuf,
+                          uint32_t pos_x, uint32_t pos_y);
+void dpy_gl_release_dmabuf(QemuConsole *con,
+                           QemuDmaBuf *dmabuf);
 void dpy_gl_update(QemuConsole *con,
                    uint32_t x, uint32_t y, uint32_t w, uint32_t h);
 
@@ -298,6 +322,7 @@ int dpy_gl_ctx_make_current(QemuConsole *con, QEMUGLContext ctx);
 QEMUGLContext dpy_gl_ctx_get_current(QemuConsole *con);
 
 bool console_has_gl(QemuConsole *con);
+bool console_has_gl_dmabuf(QemuConsole *con);
 
 static inline int surface_stride(DisplaySurface *s)
 {

ui/console.c

@@ -1404,6 +1404,11 @@ bool console_has_gl(QemuConsole *con)
     return con->gl != NULL;
 }
 
+bool console_has_gl_dmabuf(QemuConsole *con)
+{
+    return con->gl != NULL && con->gl->ops->dpy_gl_scanout_dmabuf != NULL;
+}
+
 void register_displaychangelistener(DisplayChangeListener *dcl)
 {
     static const char nodev[] =
@@ -1745,6 +1750,34 @@ void dpy_gl_scanout_texture(QemuConsole *con,
                                          x, y, width, height);
 }
 
+void dpy_gl_scanout_dmabuf(QemuConsole *con,
+                           QemuDmaBuf *dmabuf)
+{
+    assert(con->gl);
+    con->gl->ops->dpy_gl_scanout_dmabuf(con->gl, dmabuf);
+}
+
+void dpy_gl_cursor_dmabuf(QemuConsole *con,
+                          QemuDmaBuf *dmabuf,
+                          uint32_t pos_x, uint32_t pos_y)
+{
+    assert(con->gl);
+
+    if (con->gl->ops->dpy_gl_cursor_dmabuf) {
+        con->gl->ops->dpy_gl_cursor_dmabuf(con->gl, dmabuf, pos_x, pos_y);
+    }
+}
+
+void dpy_gl_release_dmabuf(QemuConsole *con,
+                          QemuDmaBuf *dmabuf)
+{
+    assert(con->gl);
+
+    if (con->gl->ops->dpy_gl_release_dmabuf) {
+        con->gl->ops->dpy_gl_release_dmabuf(con->gl, dmabuf);
+    }
+}
+
 void dpy_gl_update(QemuConsole *con,
                    uint32_t x, uint32_t y, uint32_t w, uint32_t h)
 {