From: Colin Cross <ccross@android.com>
Date: Fri, 23 Aug 2013 02:29:44 +0000 (-0700)
Subject: ion: don't use id 0 for handle cookie
X-Git-Tag: firefly_0821_release~4090^2~504
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=66df93b4c9e78cf433b76d7fe3da4cc7fd06c36b;p=firefly-linux-kernel-4.4.55.git

ion: don't use id 0 for handle cookie

ion userspace clients think that the cookie is a pointer, so they
use NULL to check if the handle has been initialized.  Set the first
id number to 1.

Change-Id: Ifb9af6029a8b08f57e41bc6160cc11e11001a2a9
Signed-off-by: Colin Cross <ccross@android.com>
---

diff --git a/drivers/gpu/ion/ion.c b/drivers/gpu/ion/ion.c
index 9f73052c3920..1d4c8876ab5c 100644
--- a/drivers/gpu/ion/ion.c
+++ b/drivers/gpu/ion/ion.c
@@ -424,7 +424,7 @@ static int ion_handle_add(struct ion_client *client, struct ion_handle *handle)
 		rc = idr_pre_get(&client->idr, GFP_KERNEL);
 		if (!rc)
 			return -ENOMEM;
-		rc = idr_get_new(&client->idr, handle, &id);
+		rc = idr_get_new_above(&client->idr, handle, 1, &id);
 		handle->id = id;
 	} while (rc == -EAGAIN);