greybus: kill gbuf->kref

Since there is only ever one reference to a gbuf, we don't need a
kref to figure out when it can be freed.  Get rid of the kref and
its supporting code.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/staging/greybus/gbuf.c

@@ -12,7 +12,6 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/kernel.h>
-#include <linux/kref.h>
 #include <linux/device.h>
 #include <linux/slab.h>
 
@@ -46,7 +45,6 @@ struct gbuf *greybus_alloc_gbuf(struct greybus_host_device *hd,
 	if (!gbuf)
 		return NULL;
 
-	kref_init(&gbuf->kref);
 	gbuf->hd = hd;
 	gbuf->dest_cport_id = dest_cport_id;
 	gbuf->status = -EBADR;	/* Initial value--means "never set" */
@@ -62,20 +60,12 @@ struct gbuf *greybus_alloc_gbuf(struct greybus_host_device *hd,
 }
 EXPORT_SYMBOL_GPL(greybus_alloc_gbuf);
 
-static void free_gbuf(struct kref *kref)
+void greybus_free_gbuf(struct gbuf *gbuf)
 {
-	struct gbuf *gbuf = container_of(kref, struct gbuf, kref);
-
 	gbuf->hd->driver->free_gbuf_data(gbuf);
 
 	kmem_cache_free(gbuf_head_cache, gbuf);
 }
-
-void greybus_free_gbuf(struct gbuf *gbuf)
-{
-	/* drop the reference count and get out of here */
-	kref_put(&gbuf->kref, free_gbuf);
-}
 EXPORT_SYMBOL_GPL(greybus_free_gbuf);
 
 int greybus_submit_gbuf(struct gbuf *gbuf, gfp_t gfp_mask)

drivers/staging/greybus/greybus.h

@@ -119,8 +119,6 @@
 */
 
 struct gbuf {
-	struct kref kref;
-
 	struct greybus_host_device *hd;
 	u16 dest_cport_id;		/* Destination CPort id */
 	int status;