Module Name: src
Committed By: riastradh
Date: Wed Jul 24 01:51:36 UTC 2013
Modified Files:
src/sys/external/bsd/drm2/include/linux [riastradh-drm2]: kref.h
Log Message:
Implement krefs in <linux/kref.h>.
To generate a diff of this commit:
cvs rdiff -u -r1.1.2.1 -r1.1.2.2 \
src/sys/external/bsd/drm2/include/linux/kref.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/external/bsd/drm2/include/linux/kref.h
diff -u src/sys/external/bsd/drm2/include/linux/kref.h:1.1.2.1 src/sys/external/bsd/drm2/include/linux/kref.h:1.1.2.2
--- src/sys/external/bsd/drm2/include/linux/kref.h:1.1.2.1 Wed Jul 24 00:33:12 2013
+++ src/sys/external/bsd/drm2/include/linux/kref.h Wed Jul 24 01:51:36 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: kref.h,v 1.1.2.1 2013/07/24 00:33:12 riastradh Exp $ */
+/* $NetBSD: kref.h,v 1.1.2.2 2013/07/24 01:51:36 riastradh Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -32,4 +32,79 @@
#ifndef _LINUX_KREF_H_
#define _LINUX_KREF_H_
+#include <sys/types.h>
+#include <sys/atomic.h>
+#include <sys/systm.h>
+
+#include <linux/mutex.h>
+
+struct kref {
+ unsigned int kr_count;
+};
+
+static inline void
+kref_init(struct kref *kref)
+{
+ kref->kr_count = 1;
+}
+
+static inline void
+kref_get(struct kref *kref)
+{
+ const unsigned int count __unused =
+ atomic_inc_uint_nv(&kref->kr_count);
+
+ KASSERT(count > 1);
+}
+
+static inline int
+kref_sub(struct kref *kref, unsigned int count, void (*release)(struct kref *))
+{
+ unsigned int old, new;
+
+ do {
+ old = kref->kr_count;
+ KASSERT(count <= old);
+ new = (old - count);
+ } while (atomic_cas_uint(&kref->kr_count, old, new) == old);
+
+ if (new == 0) {
+ (*release)(kref);
+ return 1;
+ }
+
+ return 0;
+}
+
+static inline int
+kref_put(struct kref *kref, void (*release)(struct kref *))
+{
+
+ return kref_sub(kref, 1, release);
+}
+
+static inline int
+kref_put_mutex(struct kref *kref, void (*release)(struct kref *),
+ struct mutex *interlock)
+{
+ unsigned int old, new;
+
+ do {
+ old = kref->kr_count;
+ KASSERT(old > 0);
+ if (old == 1) {
+ mutex_lock(interlock);
+ if (atomic_add_int_nv(&kref->kr_count, -1) == 0) {
+ (*release)(kref);
+ return 1;
+ }
+ mutex_unlock(interlock);
+ return 0;
+ }
+ new = (old - 1);
+ } while (atomic_cas_uint(&kref->kr_count, old, new) != old);
+
+ return 0;
+}
+
#endif /* _LINUX_KREF_H_ */
