x86: Split atomic64_t functions into seperate headers

Split atomic64_t functions out into separate headers, since they will
not be practical to merge between 32 and 64 bits.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1262883215-4034-2-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 160 insertions, 0 deletions

diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h
new file mode 100644
index 000000000000..03027bf28de5
--- /dev/null
+++ b/arch/x86/include/asm/atomic64_32.h
@@ -0,0 +1,160 @@
+#ifndef _ASM_X86_ATOMIC64_32_H
+#define _ASM_X86_ATOMIC64_32_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/processor.h>
+//#include <asm/cmpxchg.h>
+
+/* An 64bit atomic type */
+
+typedef struct {
+        u64 __aligned(8) counter;
+} atomic64_t;
+
+#define ATOMIC64_INIT(val)      { (val) }
+
+extern u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val);
+
+/**
+ * atomic64_xchg - xchg atomic64 variable
+ * @ptr:      pointer to type atomic64_t
+ * @new_val:  value to assign
+ *
+ * Atomically xchgs the value of @ptr to @new_val and returns
+ * the old value.
+ */
+extern u64 atomic64_xchg(atomic64_t *ptr, u64 new_val);
+
+/**
+ * atomic64_set - set atomic64 variable
+ * @ptr:      pointer to type atomic64_t
+ * @new_val:  value to assign
+ *
+ * Atomically sets the value of @ptr to @new_val.
+ */
+extern void atomic64_set(atomic64_t *ptr, u64 new_val);
+
+/**
+ * atomic64_read - read atomic64 variable
+ * @ptr:      pointer to type atomic64_t
+ *
+ * Atomically reads the value of @ptr and returns it.
+ */
+static inline u64 atomic64_read(atomic64_t *ptr)
+{
+        u64 res;
+
+        /*
+         * Note, we inline this atomic64_t primitive because
+         * it only clobbers EAX/EDX and leaves the others
+         * untouched. We also (somewhat subtly) rely on the
+         * fact that cmpxchg8b returns the current 64-bit value
+         * of the memory location we are touching:
+         */
+        asm volatile(
+                "mov %%ebx, %%eax\n\t"
+                "mov %%ecx, %%edx\n\t"
+                LOCK_PREFIX "cmpxchg8b %1\n"
+                        : "=&A" (res)
+                        : "m" (*ptr)
+                );
+
+        return res;
+}
+
+extern u64 atomic64_read(atomic64_t *ptr);
+
+/**
+ * atomic64_add_return - add and return
+ * @delta: integer value to add
+ * @ptr:   pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns @delta + *@ptr
+ */
+extern u64 atomic64_add_return(u64 delta, atomic64_t *ptr);
+
+/*
+ * Other variants with different arithmetic operators:
+ */
+extern u64 atomic64_sub_return(u64 delta, atomic64_t *ptr);
+extern u64 atomic64_inc_return(atomic64_t *ptr);
+extern u64 atomic64_dec_return(atomic64_t *ptr);
+
+/**
+ * atomic64_add - add integer to atomic64 variable
+ * @delta: integer value to add
+ * @ptr:   pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr.
+ */
+extern void atomic64_add(u64 delta, atomic64_t *ptr);
+
+/**
+ * atomic64_sub - subtract the atomic64 variable
+ * @delta: integer value to subtract
+ * @ptr:   pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr.
+ */
+extern void atomic64_sub(u64 delta, atomic64_t *ptr);
+
+/**
+ * atomic64_sub_and_test - subtract value from variable and test result
+ * @delta: integer value to subtract
+ * @ptr:   pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr and returns
+ * true if the result is zero, or false for all
+ * other cases.
+ */
+extern int atomic64_sub_and_test(u64 delta, atomic64_t *ptr);
+
+/**
+ * atomic64_inc - increment atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1.
+ */
+extern void atomic64_inc(atomic64_t *ptr);
+
+/**
+ * atomic64_dec - decrement atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1.
+ */
+extern void atomic64_dec(atomic64_t *ptr);
+
+/**
+ * atomic64_dec_and_test - decrement and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases.
+ */
+extern int atomic64_dec_and_test(atomic64_t *ptr);
+
+/**
+ * atomic64_inc_and_test - increment and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+extern int atomic64_inc_and_test(atomic64_t *ptr);
+
+/**
+ * atomic64_add_negative - add and test if negative
+ * @delta: integer value to add
+ * @ptr:   pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns true
+ * if the result is negative, or false when
+ * result is greater than or equal to zero.
+ */
+extern int atomic64_add_negative(u64 delta, atomic64_t *ptr);
+
+#endif /* _ASM_X86_ATOMIC64_32_H */