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-rw-r--r--arch/sparc/lib/atomic32.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c
new file mode 100644
index 000000000000..19724c5800a7
--- /dev/null
+++ b/arch/sparc/lib/atomic32.c
@@ -0,0 +1,53 @@
+/*
+ * atomic32.c: 32-bit atomic_t implementation
+ *
+ * Copyright (C) 2004 Keith M Wesolowski
+ *
+ * Based on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf
+ */
+
+#include <asm/atomic.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+
+#ifdef CONFIG_SMP
+#define ATOMIC_HASH_SIZE 4
+#define ATOMIC_HASH(a) (&__atomic_hash[(((unsigned long)a)>>8) & (ATOMIC_HASH_SIZE-1)])
+
+spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] = {
+ [0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED
+};
+
+#else /* SMP */
+
+static spinlock_t dummy = SPIN_LOCK_UNLOCKED;
+#define ATOMIC_HASH_SIZE 1
+#define ATOMIC_HASH(a) (&dummy)
+
+#endif /* SMP */
+
+int __atomic_add_return(int i, atomic_t *v)
+{
+ int ret;
+ unsigned long flags;
+ spin_lock_irqsave(ATOMIC_HASH(v), flags);
+
+ ret = (v->counter += i);
+
+ spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
+ return ret;
+}
+
+void atomic_set(atomic_t *v, int i)
+{
+ unsigned long flags;
+ spin_lock_irqsave(ATOMIC_HASH(v), flags);
+
+ v->counter = i;
+
+ spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
+}
+
+EXPORT_SYMBOL(__atomic_add_return);
+EXPORT_SYMBOL(atomic_set);
+