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!

1 files changed, 299 insertions, 0 deletions

diff --git a/include/asm-mips/spinlock.h b/include/asm-mips/spinlock.h
new file mode 100644
index 0000000..114d3eb
--- /dev/null
+++ b/include/asm-mips/spinlock.h
@@ -0,0 +1,299 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1999, 2000 by Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ */
+#ifndef _ASM_SPINLOCK_H
+#define _ASM_SPINLOCK_H
+
+#include <linux/config.h>
+#include <asm/war.h>
+
+/*
+ * Your basic SMP spinlocks, allowing only a single CPU anywhere
+ */
+
+typedef struct {
+	volatile unsigned int lock;
+#ifdef CONFIG_PREEMPT
+	unsigned int break_lock;
+#endif
+} spinlock_t;
+
+#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
+
+#define spin_lock_init(x)	do { (x)->lock = 0; } while(0)
+
+#define spin_is_locked(x)	((x)->lock != 0)
+#define spin_unlock_wait(x)	do { barrier(); } while ((x)->lock)
+#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
+
+/*
+ * Simple spin lock operations.  There are two variants, one clears IRQ's
+ * on the local processor, one does not.
+ *
+ * We make no fairness assumptions.  They have a cost.
+ */
+
+static inline void _raw_spin_lock(spinlock_t *lock)
+{
+	unsigned int tmp;
+
+	if (R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_spin_lock	\n"
+		"1:	ll	%1, %2					\n"
+		"	bnez	%1, 1b					\n"
+		"	 li	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqzl	%1, 1b					\n"
+		"	 nop						\n"
+		"	sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (lock->lock), "=&r" (tmp)
+		: "m" (lock->lock)
+		: "memory");
+	} else {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_spin_lock	\n"
+		"1:	ll	%1, %2					\n"
+		"	bnez	%1, 1b					\n"
+		"	 li	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqz	%1, 1b					\n"
+		"	 sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (lock->lock), "=&r" (tmp)
+		: "m" (lock->lock)
+		: "memory");
+	}
+}
+
+static inline void _raw_spin_unlock(spinlock_t *lock)
+{
+	__asm__ __volatile__(
+	"	.set	noreorder	# _raw_spin_unlock	\n"
+	"	sync						\n"
+	"	sw	$0, %0					\n"
+	"	.set\treorder					\n"
+	: "=m" (lock->lock)
+	: "m" (lock->lock)
+	: "memory");
+}
+
+static inline unsigned int _raw_spin_trylock(spinlock_t *lock)
+{
+	unsigned int temp, res;
+
+	if (R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_spin_trylock	\n"
+		"1:	ll	%0, %3					\n"
+		"	ori	%2, %0, 1				\n"
+		"	sc	%2, %1					\n"
+		"	beqzl	%2, 1b					\n"
+		"	 nop						\n"
+		"	andi	%2, %0, 1				\n"
+		"	sync						\n"
+		"	.set	reorder"
+		: "=&r" (temp), "=m" (lock->lock), "=&r" (res)
+		: "m" (lock->lock)
+		: "memory");
+	} else {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_spin_trylock	\n"
+		"1:	ll	%0, %3					\n"
+		"	ori	%2, %0, 1				\n"
+		"	sc	%2, %1					\n"
+		"	beqz	%2, 1b					\n"
+		"	 andi	%2, %0, 1				\n"
+		"	sync						\n"
+		"	.set	reorder"
+		: "=&r" (temp), "=m" (lock->lock), "=&r" (res)
+		: "m" (lock->lock)
+		: "memory");
+	}
+
+	return res == 0;
+}
+
+/*
+ * Read-write spinlocks, allowing multiple readers but only one writer.
+ *
+ * NOTE! it is quite common to have readers in interrupts but no interrupt
+ * writers. For those circumstances we can "mix" irq-safe locks - any writer
+ * needs to get a irq-safe write-lock, but readers can get non-irqsafe
+ * read-locks.
+ */
+
+typedef struct {
+	volatile unsigned int lock;
+#ifdef CONFIG_PREEMPT
+	unsigned int break_lock;
+#endif
+} rwlock_t;
+
+#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
+
+#define rwlock_init(x)  do { *(x) = RW_LOCK_UNLOCKED; } while(0)
+
+static inline void _raw_read_lock(rwlock_t *rw)
+{
+	unsigned int tmp;
+
+	if (R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_read_lock	\n"
+		"1:	ll	%1, %2					\n"
+		"	bltz	%1, 1b					\n"
+		"	 addu	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqzl	%1, 1b					\n"
+		"	 nop						\n"
+		"	sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (rw->lock), "=&r" (tmp)
+		: "m" (rw->lock)
+		: "memory");
+	} else {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_read_lock	\n"
+		"1:	ll	%1, %2					\n"
+		"	bltz	%1, 1b					\n"
+		"	 addu	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqz	%1, 1b					\n"
+		"	 sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (rw->lock), "=&r" (tmp)
+		: "m" (rw->lock)
+		: "memory");
+	}
+}
+
+/* Note the use of sub, not subu which will make the kernel die with an
+   overflow exception if we ever try to unlock an rwlock that is already
+   unlocked or is being held by a writer.  */
+static inline void _raw_read_unlock(rwlock_t *rw)
+{
+	unsigned int tmp;
+
+	if (R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"1:	ll	%1, %2		# _raw_read_unlock	\n"
+		"	sub	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqzl	%1, 1b					\n"
+		"	sync						\n"
+		: "=m" (rw->lock), "=&r" (tmp)
+		: "m" (rw->lock)
+		: "memory");
+	} else {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_read_unlock	\n"
+		"1:	ll	%1, %2					\n"
+		"	sub	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqz	%1, 1b					\n"
+		"	 sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (rw->lock), "=&r" (tmp)
+		: "m" (rw->lock)
+		: "memory");
+	}
+}
+
+static inline void _raw_write_lock(rwlock_t *rw)
+{
+	unsigned int tmp;
+
+	if (R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_write_lock	\n"
+		"1:	ll	%1, %2					\n"
+		"	bnez	%1, 1b					\n"
+		"	 lui	%1, 0x8000				\n"
+		"	sc	%1, %0					\n"
+		"	beqzl	%1, 1b					\n"
+		"	 nop						\n"
+		"	sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (rw->lock), "=&r" (tmp)
+		: "m" (rw->lock)
+		: "memory");
+	} else {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_write_lock	\n"
+		"1:	ll	%1, %2					\n"
+		"	bnez	%1, 1b					\n"
+		"	 lui	%1, 0x8000				\n"
+		"	sc	%1, %0					\n"
+		"	beqz	%1, 1b					\n"
+		"	 nop						\n"
+		"	sync						\n"
+		"	.set	reorder					\n"
+		: "=m" (rw->lock), "=&r" (tmp)
+		: "m" (rw->lock)
+		: "memory");
+	}
+}
+
+static inline void _raw_write_unlock(rwlock_t *rw)
+{
+	__asm__ __volatile__(
+	"	sync			# _raw_write_unlock	\n"
+	"	sw	$0, %0					\n"
+	: "=m" (rw->lock)
+	: "m" (rw->lock)
+	: "memory");
+}
+
+#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)
+
+static inline int _raw_write_trylock(rwlock_t *rw)
+{
+	unsigned int tmp;
+	int ret;
+
+	if (R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_write_trylock	\n"
+		"	li	%2, 0					\n"
+		"1:	ll	%1, %3					\n"
+		"	bnez	%1, 2f					\n"
+		"	 lui	%1, 0x8000				\n"
+		"	sc	%1, %0					\n"
+		"	beqzl	%1, 1b					\n"
+		"	 nop						\n"
+		"	sync						\n"
+		"	li	%2, 1					\n"
+		"	.set	reorder					\n"
+		"2:							\n"
+		: "=m" (rw->lock), "=&r" (tmp), "=&r" (ret)
+		: "m" (rw->lock)
+		: "memory");
+	} else {
+		__asm__ __volatile__(
+		"	.set	noreorder	# _raw_write_trylock	\n"
+		"	li	%2, 0					\n"
+		"1:	ll	%1, %3					\n"
+		"	bnez	%1, 2f					\n"
+		"	lui	%1, 0x8000				\n"
+		"	sc	%1, %0					\n"
+		"	beqz	%1, 1b					\n"
+		"	 sync						\n"
+		"	li	%2, 1					\n"
+		"	.set	reorder					\n"
+		"2:							\n"
+		: "=m" (rw->lock), "=&r" (tmp), "=&r" (ret)
+		: "m" (rw->lock)
+		: "memory");
+	}
+
+	return ret;
+}
+
+#endif /* _ASM_SPINLOCK_H */