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-rw-r--r--arch/sh/include/asm/futex-cas.h35
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/sh/include/asm/futex-cas.h b/arch/sh/include/asm/futex-cas.h
new file mode 100644
index 0000000000..ed738e32b5
--- /dev/null
+++ b/arch/sh/include/asm/futex-cas.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_SH_FUTEX_CAS_H
+#define __ASM_SH_FUTEX_CAS_H
+
+static inline int atomic_futex_op_cmpxchg_inatomic(u32 *uval,
+ u32 __user *uaddr,
+ u32 oldval, u32 newval)
+{
+ int err = 0;
+ __asm__ __volatile__(
+ "1:\n\t"
+ "cas.l %2, %1, @r0\n"
+ "2:\n\t"
+#ifdef CONFIG_MMU
+ ".section .fixup,\"ax\"\n"
+ "3:\n\t"
+ "mov.l 4f, %0\n\t"
+ "jmp @%0\n\t"
+ " mov %3, %0\n\t"
+ ".balign 4\n"
+ "4: .long 2b\n\t"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n\t"
+ ".long 1b, 3b\n\t"
+ ".previous"
+#endif
+ :"+r" (err), "+r" (newval)
+ :"r" (oldval), "i" (-EFAULT), "z" (uaddr)
+ :"t", "memory");
+ if (err) return err;
+ *uval = newval;
+ return 0;
+}
+
+#endif /* __ASM_SH_FUTEX_CAS_H */