DRI2: Free DRI2 drawable references in DRI2DestroyDrawable

If client calls DRI2CreateDrawable multiple times for same drawable
DRI2 creates multiple references. Multiple references cause DRI2 send
multiple invalidate events for same client.

Problem is triggered because client side EGL implementation is using
DRI2 directly.

DRI2 code in server doesn't handle DRI2DestroyDrawable that leaks
references. If client recreates rendering target EGL destroys and
creates DRI2 drawable. In that case DRI2DestroyDrawable leaks DRI2
drawable references.

To fix this memory leak/performance problem server has to free the
reference when client requests for it.

Signed-off-by: Pauli Nieminen <ext-pauli.nieminen@nokia.com>
Reviewed-By: Christopher James Halse Rogers <christopher.halse.rogers@canonical.com>

3 files changed, 35 insertions, 2 deletions

diff --git a/hw/xfree86/dri2/dri2.c b/hw/xfree86/dri2/dri2.c
index 39996f946..66d217cc8 100644
--- a/hw/xfree86/dri2/dri2.c
+++ b/hw/xfree86/dri2/dri2.c
@@ -211,6 +211,18 @@ DRI2LookupDrawableRef(DRI2DrawablePtr pPriv, XID id)
     return NULL;
 }
 
+static DRI2DrawableRefPtr
+DRI2LookupClientDrawableRef(DRI2DrawablePtr pPriv, ClientPtr client, XID id)
+{
+    DRI2DrawableRefPtr ref;
+
+    list_for_each_entry(ref, &pPriv->reference_list, link) {
+	if (CLIENT_ID(ref->dri2_id) == client->index && ref->id == id)
+	    return ref;
+    }
+    return NULL;
+}
+
 static int
 DRI2AddDrawableRef(DRI2DrawablePtr pPriv, XID id, XID dri2_id,
 		   DRI2InvalidateProcPtr invalidate, void *priv)
@@ -258,6 +270,25 @@ DRI2CreateDrawable(ClientPtr client, DrawablePtr pDraw, XID id,
     return Success;
 }
 
+int
+DRI2DestroyDrawable(ClientPtr client, DrawablePtr pDraw, XID id)
+{
+    DRI2DrawableRefPtr ref;
+    DRI2DrawablePtr pPriv = DRI2GetDrawable(pDraw);
+
+    if (!pPriv)
+	return BadDrawable;
+
+    ref = DRI2LookupClientDrawableRef(pPriv, client, id);
+
+    if (!ref)
+	return BadDrawable;
+
+    FreeResourceByType(ref->dri2_id, dri2DrawableRes, FALSE);
+
+    return Success;
+}
+
 static int DRI2DrawableGone(pointer p, XID id)
 {
     DRI2DrawablePtr pPriv = p;
diff --git a/hw/xfree86/dri2/dri2.h b/hw/xfree86/dri2/dri2.h
index fe0bf6ccb..dd63c3029 100644
--- a/hw/xfree86/dri2/dri2.h
+++ b/hw/xfree86/dri2/dri2.h
@@ -214,7 +214,9 @@ extern _X_EXPORT int DRI2CreateDrawable(ClientPtr client,
 					DRI2InvalidateProcPtr invalidate,
 					void *priv);
 
-extern _X_EXPORT void DRI2DestroyDrawable(DrawablePtr pDraw);
+extern _X_EXPORT int DRI2DestroyDrawable(ClientPtr client,
+                                         DrawablePtr pDraw,
+                                         XID id);
 
 extern _X_EXPORT DRI2BufferPtr *DRI2GetBuffers(DrawablePtr pDraw,
 			     int *width,
diff --git a/hw/xfree86/dri2/dri2ext.c b/hw/xfree86/dri2/dri2ext.c
index 4e48e65b2..c7e6be1ce 100644
--- a/hw/xfree86/dri2/dri2ext.c
+++ b/hw/xfree86/dri2/dri2ext.c
@@ -200,7 +200,7 @@ ProcDRI2DestroyDrawable(ClientPtr client)
 		       &pDrawable, &status))
 	return status;
 
-    return Success;
+    return DRI2DestroyDrawable(client, pDrawable, stuff->drawable);
 }