1 files changed, 74 insertions, 4 deletions

diff --git a/src/gallium/winsys/nouveau/drm/nouveau_drm_winsys.c b/src/gallium/winsys/nouveau/drm/nouveau_drm_winsys.c
index e4f27f6cb24..a077c48c206 100644
--- a/src/gallium/winsys/nouveau/drm/nouveau_drm_winsys.c
+++ b/src/gallium/winsys/nouveau/drm/nouveau_drm_winsys.c
@@ -1,24 +1,83 @@
+#include <sys/stat.h>
 #include "pipe/p_context.h"
 #include "pipe/p_state.h"
 #include "util/u_format.h"
 #include "util/u_memory.h"
 #include "util/u_inlines.h"
+#include "util/u_hash_table.h"
+#include "os/os_thread.h"
 
 #include "nouveau_drm_public.h"
 
 #include "nouveau/nouveau_winsys.h"
 #include "nouveau/nouveau_screen.h"
 
-struct pipe_screen *
+static struct util_hash_table *fd_tab = NULL;
+
+pipe_static_mutex(nouveau_screen_mutex);
+
+boolean nouveau_drm_screen_unref(struct nouveau_screen *screen)
+{
+	int ret;
+	if (screen->refcount == -1)
+		return true;
+
+	pipe_mutex_lock(nouveau_screen_mutex);
+	ret = --screen->refcount;
+	assert(ret >= 0);
+	if (ret == 0)
+		util_hash_table_remove(fd_tab, intptr_to_pointer(screen->device->fd));
+	pipe_mutex_unlock(nouveau_screen_mutex);
+	return ret == 0;
+}
+
+static unsigned hash_fd(void *key)
+{
+    int fd = pointer_to_intptr(key);
+    struct stat stat;
+    fstat(fd, &stat);
+
+    return stat.st_dev ^ stat.st_ino ^ stat.st_rdev;
+}
+
+static int compare_fd(void *key1, void *key2)
+{
+    int fd1 = pointer_to_intptr(key1);
+    int fd2 = pointer_to_intptr(key2);
+    struct stat stat1, stat2;
+    fstat(fd1, &stat1);
+    fstat(fd2, &stat2);
+
+    return stat1.st_dev != stat2.st_dev ||
+           stat1.st_ino != stat2.st_ino ||
+           stat1.st_rdev != stat2.st_rdev;
+}
+
+PUBLIC struct pipe_screen *
 nouveau_drm_screen_create(int fd)
 {
 	struct nouveau_device *dev = NULL;
 	struct pipe_screen *(*init)(struct nouveau_device *);
+	struct nouveau_screen *screen;
 	int ret;
 
+	pipe_mutex_lock(nouveau_screen_mutex);
+	if (!fd_tab) {
+		fd_tab = util_hash_table_create(hash_fd, compare_fd);
+		if (!fd_tab)
+			goto err;
+	}
+
+	screen = util_hash_table_get(fd_tab, intptr_to_pointer(fd));
+	if (screen) {
+		screen->refcount++;
+		pipe_mutex_unlock(nouveau_screen_mutex);
+		return &screen->base;
+	}
+
 	ret = nouveau_device_wrap(fd, 0, &dev);
 	if (ret)
-		return NULL;
+		goto err;
 
 	switch (dev->chipset & ~0xf) {
 	case 0x30:
@@ -42,8 +101,19 @@ nouveau_drm_screen_create(int fd)
 	default:
 		debug_printf("%s: unknown chipset nv%02x\n", __func__,
 			     dev->chipset);
-		return NULL;
+		goto err;
 	}
 
-	return init(dev);
+	screen = (struct nouveau_screen*)init(dev);
+	if (!screen)
+		goto err;
+
+	util_hash_table_set(fd_tab, intptr_to_pointer(fd), screen);
+	screen->refcount = 1;
+	pipe_mutex_unlock(nouveau_screen_mutex);
+	return &screen->base;
+
+err:
+	pipe_mutex_unlock(nouveau_screen_mutex);
+	return NULL;
 }