1 files changed, 62 insertions, 0 deletions

diff --git a/firmware/kernel/include/mutex.h b/firmware/kernel/include/mutex.h
new file mode 100644
index 0000000000..bcf5701bd9
--- /dev/null
+++ b/firmware/kernel/include/mutex.h
@@ -0,0 +1,62 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#ifndef MUTEX_H
+#define MUTEX_H
+
+#include <stdbool.h>
+#include "config.h"
+#include "thread.h"
+
+struct mutex
+{
+    struct thread_entry *queue;         /* waiter list */
+    int recursion;                      /* lock owner recursion count */
+#ifdef HAVE_PRIORITY_SCHEDULING
+    struct blocker blocker;             /* priority inheritance info
+                                           for waiters */
+    bool no_preempt;                    /* don't allow higher-priority thread
+                                           to be scheduled even if woken */
+#else
+    struct thread_entry *thread;        /* Indicates owner thread - an owner
+                                           implies a locked state - same goes
+                                           for priority scheduling
+                                           (in blocker struct for that) */
+#endif
+    IF_COP( struct corelock cl; )       /* multiprocessor sync */
+};
+
+extern void mutex_init(struct mutex *m);
+extern void mutex_lock(struct mutex *m);
+extern void mutex_unlock(struct mutex *m);
+#ifdef HAVE_PRIORITY_SCHEDULING
+/* Deprecated temporary function to disable mutex preempting a thread on
+ * unlock - firmware/drivers/fat.c and a couple places in apps/buffering.c -
+ * reliance on it is a bug! */
+static inline void mutex_set_preempt(struct mutex *m, bool preempt)
+    { m->no_preempt = !preempt; }
+#else
+/* Deprecated but needed for now - firmware/drivers/ata_mmc.c */
+static inline bool mutex_test(const struct mutex *m)
+    { return m->thread != NULL; }
+#endif /* HAVE_PRIORITY_SCHEDULING */
+
+#endif /* MUTEX_H */