vc4: add hash table look-up for exported dmabufs

It is necessary to reuse existing BOs when dmabufs are imported. There
are 2 cases that need to be handled. dmabufs can be created/exported and
imported by the same process and can be imported multiple times.
Copying other drivers, add a hash table to track exported BOs so the
BOs get reused.

v2: Whitespace fixup (by anholt)

Signed-off-by: Rob Herring <[email protected]>
Reviewed-by: Eric Anholt <[email protected]>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/gallium/drivers/vc4/vc4_screen.c b/src/gallium/drivers/vc4/vc4_screen.c
index 5882f070340..aeb6c9a784e 100644
--- a/src/gallium/drivers/vc4/vc4_screen.c
+++ b/src/gallium/drivers/vc4/vc4_screen.c
@@ -30,6 +30,7 @@
 #include "util/u_debug.h"
 #include "util/u_memory.h"
 #include "util/u_format.h"
+#include "util/u_hash_table.h"
 #include "util/ralloc.h"
 
 #include <xf86drm.h>
@@ -508,6 +509,18 @@ vc4_screen_is_format_supported(struct pipe_screen *pscreen,
         return retval == usage;
 }
 
+#define PTR_TO_UINT(x) ((unsigned)((intptr_t)(x)))
+
+static unsigned handle_hash(void *key)
+{
+    return PTR_TO_UINT(key);
+}
+
+static int handle_compare(void *key1, void *key2)
+{
+    return PTR_TO_UINT(key1) != PTR_TO_UINT(key2);
+}
+
 static bool
 vc4_supports_branches(struct vc4_screen *screen)
 {
@@ -595,6 +608,8 @@ vc4_screen_create(int fd)
 
         screen->fd = fd;
         list_inithead(&screen->bo_cache.time_list);
+        pipe_mutex_init(screen->bo_handles_mutex);
+        screen->bo_handles = util_hash_table_create(handle_hash, handle_compare);
 
         if (vc4_supports_branches(screen))
                 screen->has_control_flow = true;