Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/include/asm-parisc/semaphore.h b/include/asm-parisc/semaphore.h
new file mode 100644
index 0000000..f78bb2e
--- /dev/null
+++ b/include/asm-parisc/semaphore.h
@@ -0,0 +1,147 @@
+/* SMP- and interrupt-safe semaphores.
+ * PA-RISC version by Matthew Wilcox
+ *
+ * Linux/PA-RISC Project (http://www.parisc-linux.org/)
+ * Copyright (C) 1996 Linus Torvalds
+ * Copyright (C) 1999-2001 Matthew Wilcox < willy at debian d0T org >
+ * Copyright (C) 2000 Grant Grundler < grundler a debian org >
+ *
+ * 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 program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _ASM_PARISC_SEMAPHORE_H
+#define _ASM_PARISC_SEMAPHORE_H
+
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+#include <linux/rwsem.h>
+
+#include <asm/system.h>
+
+/*
+ * The `count' is initialised to the number of people who are allowed to
+ * take the lock. (Normally we want a mutex, so this is `1'). if
+ * `count' is positive, the lock can be taken. if it's 0, no-one is
+ * waiting on it. if it's -1, at least one task is waiting.
+ */
+struct semaphore {
+ spinlock_t sentry;
+ int count;
+ wait_queue_head_t wait;
+};
+
+#define __SEMAPHORE_INITIALIZER(name, n) \
+{ \
+ .sentry = SPIN_LOCK_UNLOCKED, \
+ .count = n, \
+ .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
+}
+
+#define __MUTEX_INITIALIZER(name) \
+ __SEMAPHORE_INITIALIZER(name,1)
+
+#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
+ struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
+
+#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
+#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
+
+extern inline void sema_init (struct semaphore *sem, int val)
+{
+ *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val);
+}
+
+static inline void init_MUTEX (struct semaphore *sem)
+{
+ sema_init(sem, 1);
+}
+
+static inline void init_MUTEX_LOCKED (struct semaphore *sem)
+{
+ sema_init(sem, 0);
+}
+
+static inline int sem_getcount(struct semaphore *sem)
+{
+ return sem->count;
+}
+
+asmlinkage void __down(struct semaphore * sem);
+asmlinkage int __down_interruptible(struct semaphore * sem);
+asmlinkage void __up(struct semaphore * sem);
+
+/* Semaphores can be `tried' from irq context. So we have to disable
+ * interrupts while we're messing with the semaphore. Sorry.
+ */
+
+extern __inline__ void down(struct semaphore * sem)
+{
+ might_sleep();
+ spin_lock_irq(&sem->sentry);
+ if (sem->count > 0) {
+ sem->count--;
+ } else {
+ __down(sem);
+ }
+ spin_unlock_irq(&sem->sentry);
+}
+
+extern __inline__ int down_interruptible(struct semaphore * sem)
+{
+ int ret = 0;
+ might_sleep();
+ spin_lock_irq(&sem->sentry);
+ if (sem->count > 0) {
+ sem->count--;
+ } else {
+ ret = __down_interruptible(sem);
+ }
+ spin_unlock_irq(&sem->sentry);
+ return ret;
+}
+
+/*
+ * down_trylock returns 0 on success, 1 if we failed to get the lock.
+ * May not sleep, but must preserve irq state
+ */
+extern __inline__ int down_trylock(struct semaphore * sem)
+{
+ int flags, count;
+
+ spin_lock_irqsave(&sem->sentry, flags);
+ count = sem->count - 1;
+ if (count >= 0)
+ sem->count = count;
+ spin_unlock_irqrestore(&sem->sentry, flags);
+ return (count < 0);
+}
+
+/*
+ * Note! This is subtle. We jump to wake people up only if
+ * the semaphore was negative (== somebody was waiting on it).
+ */
+extern __inline__ void up(struct semaphore * sem)
+{
+ int flags;
+ spin_lock_irqsave(&sem->sentry, flags);
+ if (sem->count < 0) {
+ __up(sem);
+ } else {
+ sem->count++;
+ }
+ spin_unlock_irqrestore(&sem->sentry, flags);
+}
+
+#endif /* _ASM_PARISC_SEMAPHORE_H */