drm/nouveau: fix gpuobj refcount to use atomics

Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 11 insertions, 22 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_object.c b/drivers/gpu/drm/nouveau/nouveau_object.c
index 198c2514f893..02a0151b0738 100644
--- a/drivers/gpu/drm/nouveau/nouveau_object.c
+++ b/drivers/gpu/drm/nouveau/nouveau_object.c
@@ -90,7 +90,7 @@ nouveau_gpuobj_new(struct drm_device *dev, struct nouveau_channel *chan,
         NV_DEBUG(dev, "gpuobj %p\n", gpuobj);
         gpuobj->dev = dev;
         gpuobj->flags = flags;
-        gpuobj->refcount = 1;
+        kref_init(&gpuobj->refcount);
         gpuobj->size = size;
 
         list_add_tail(&gpuobj->list, &dev_priv->gpuobj_list);
@@ -198,25 +198,15 @@ void
 nouveau_gpuobj_late_takedown(struct drm_device *dev)
 {
         struct drm_nouveau_private *dev_priv = dev->dev_private;
-        struct nouveau_gpuobj *gpuobj = NULL;
-        struct list_head *entry, *tmp;
-
-        NV_DEBUG(dev, "\n");
-
-        list_for_each_safe(entry, tmp, &dev_priv->gpuobj_list) {
-                gpuobj = list_entry(entry, struct nouveau_gpuobj, list);
 
-                NV_ERROR(dev, "gpuobj %p still exists at takedown, refs=%d\n",
-                         gpuobj, gpuobj->refcount);
-
-                gpuobj->refcount = 1;
-                nouveau_gpuobj_ref(NULL, &gpuobj);
-        }
+        BUG_ON(!list_empty(&dev_priv->gpuobj_list));
 }
 
-static int
-nouveau_gpuobj_del(struct nouveau_gpuobj *gpuobj)
+static void
+nouveau_gpuobj_del(struct kref *ref)
 {
+        struct nouveau_gpuobj *gpuobj =
+                container_of(ref, struct nouveau_gpuobj, refcount);
         struct drm_device *dev = gpuobj->dev;
         struct drm_nouveau_private *dev_priv = dev->dev_private;
         struct nouveau_engine *engine = &dev_priv->engine;
@@ -242,17 +232,16 @@ nouveau_gpuobj_del(struct nouveau_gpuobj *gpuobj)
         list_del(&gpuobj->list);
 
         kfree(gpuobj);
-        return 0;
 }
 
 void
 nouveau_gpuobj_ref(struct nouveau_gpuobj *ref, struct nouveau_gpuobj **ptr)
 {
         if (ref)
-                ref->refcount++;
+                kref_get(&ref->refcount);
 
-        if (*ptr && --(*ptr)->refcount == 0)
-                nouveau_gpuobj_del(*ptr);
+        if (*ptr)
+                kref_put(&(*ptr)->refcount, nouveau_gpuobj_del);
 
         *ptr = ref;
 }
@@ -275,7 +264,7 @@ nouveau_gpuobj_new_fake(struct drm_device *dev, u32 pinst, u64 vinst,
         NV_DEBUG(dev, "gpuobj %p\n", gpuobj);
         gpuobj->dev = dev;
         gpuobj->flags = flags;
-        gpuobj->refcount = 1;
+        kref_init(&gpuobj->refcount);
         gpuobj->size  = size;
         gpuobj->pinst = pinst;
         gpuobj->cinst = 0xdeadbeef;
@@ -561,7 +550,7 @@ nouveau_gpuobj_sw_new(struct nouveau_channel *chan, int class,
         gpuobj->dev = chan->dev;
         gpuobj->engine = NVOBJ_ENGINE_SW;
         gpuobj->class = class;
-        gpuobj->refcount = 1;
+        kref_init(&gpuobj->refcount);
         gpuobj->cinst = 0x40;
 
         list_add_tail(&gpuobj->list, &dev_priv->gpuobj_list);