v4.19.13 snapshot.
diff --git a/arch/m68k/include/asm/atomic.h b/arch/m68k/include/asm/atomic.h
new file mode 100644
index 0000000..47228b0
--- /dev/null
+++ b/arch/m68k/include/asm/atomic.h
@@ -0,0 +1,217 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ARCH_M68K_ATOMIC__
+#define __ARCH_M68K_ATOMIC__
+
+#include <linux/types.h>
+#include <linux/irqflags.h>
+#include <asm/cmpxchg.h>
+#include <asm/barrier.h>
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ */
+
+/*
+ * We do not have SMP m68k systems, so we don't have to deal with that.
+ */
+
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_read(v) READ_ONCE((v)->counter)
+#define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
+
+/*
+ * The ColdFire parts cannot do some immediate to memory operations,
+ * so for them we do not specify the "i" asm constraint.
+ */
+#ifdef CONFIG_COLDFIRE
+#define ASM_DI "d"
+#else
+#define ASM_DI "di"
+#endif
+
+#define ATOMIC_OP(op, c_op, asm_op) \
+static inline void atomic_##op(int i, atomic_t *v) \
+{ \
+ __asm__ __volatile__(#asm_op "l %1,%0" : "+m" (*v) : ASM_DI (i));\
+} \
+
+#ifdef CONFIG_RMW_INSNS
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
+static inline int atomic_##op##_return(int i, atomic_t *v) \
+{ \
+ int t, tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: movel %2,%1\n" \
+ " " #asm_op "l %3,%1\n" \
+ " casl %2,%1,%0\n" \
+ " jne 1b" \
+ : "+m" (*v), "=&d" (t), "=&d" (tmp) \
+ : "g" (i), "2" (atomic_read(v))); \
+ return t; \
+}
+
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ int t, tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: movel %2,%1\n" \
+ " " #asm_op "l %3,%1\n" \
+ " casl %2,%1,%0\n" \
+ " jne 1b" \
+ : "+m" (*v), "=&d" (t), "=&d" (tmp) \
+ : "g" (i), "2" (atomic_read(v))); \
+ return tmp; \
+}
+
+#else
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
+static inline int atomic_##op##_return(int i, atomic_t * v) \
+{ \
+ unsigned long flags; \
+ int t; \
+ \
+ local_irq_save(flags); \
+ t = (v->counter c_op i); \
+ local_irq_restore(flags); \
+ \
+ return t; \
+}
+
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t * v) \
+{ \
+ unsigned long flags; \
+ int t; \
+ \
+ local_irq_save(flags); \
+ t = v->counter; \
+ v->counter c_op i; \
+ local_irq_restore(flags); \
+ \
+ return t; \
+}
+
+#endif /* CONFIG_RMW_INSNS */
+
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_OP_RETURN(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(add, +=, add)
+ATOMIC_OPS(sub, -=, sub)
+
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(and, &=, and)
+ATOMIC_OPS(or, |=, or)
+ATOMIC_OPS(xor, ^=, eor)
+
+#undef ATOMIC_OPS
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+static inline void atomic_inc(atomic_t *v)
+{
+ __asm__ __volatile__("addql #1,%0" : "+m" (*v));
+}
+#define atomic_inc atomic_inc
+
+static inline void atomic_dec(atomic_t *v)
+{
+ __asm__ __volatile__("subql #1,%0" : "+m" (*v));
+}
+#define atomic_dec atomic_dec
+
+static inline int atomic_dec_and_test(atomic_t *v)
+{
+ char c;
+ __asm__ __volatile__("subql #1,%1; seq %0" : "=d" (c), "+m" (*v));
+ return c != 0;
+}
+#define atomic_dec_and_test atomic_dec_and_test
+
+static inline int atomic_dec_and_test_lt(atomic_t *v)
+{
+ char c;
+ __asm__ __volatile__(
+ "subql #1,%1; slt %0"
+ : "=d" (c), "=m" (*v)
+ : "m" (*v));
+ return c != 0;
+}
+
+static inline int atomic_inc_and_test(atomic_t *v)
+{
+ char c;
+ __asm__ __volatile__("addql #1,%1; seq %0" : "=d" (c), "+m" (*v));
+ return c != 0;
+}
+#define atomic_inc_and_test atomic_inc_and_test
+
+#ifdef CONFIG_RMW_INSNS
+
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+#else /* !CONFIG_RMW_INSNS */
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ unsigned long flags;
+ int prev;
+
+ local_irq_save(flags);
+ prev = atomic_read(v);
+ if (prev == old)
+ atomic_set(v, new);
+ local_irq_restore(flags);
+ return prev;
+}
+
+static inline int atomic_xchg(atomic_t *v, int new)
+{
+ unsigned long flags;
+ int prev;
+
+ local_irq_save(flags);
+ prev = atomic_read(v);
+ atomic_set(v, new);
+ local_irq_restore(flags);
+ return prev;
+}
+
+#endif /* !CONFIG_RMW_INSNS */
+
+static inline int atomic_sub_and_test(int i, atomic_t *v)
+{
+ char c;
+ __asm__ __volatile__("subl %2,%1; seq %0"
+ : "=d" (c), "+m" (*v)
+ : ASM_DI (i));
+ return c != 0;
+}
+#define atomic_sub_and_test atomic_sub_and_test
+
+static inline int atomic_add_negative(int i, atomic_t *v)
+{
+ char c;
+ __asm__ __volatile__("addl %2,%1; smi %0"
+ : "=d" (c), "+m" (*v)
+ : ASM_DI (i));
+ return c != 0;
+}
+#define atomic_add_negative atomic_add_negative
+
+#endif /* __ARCH_M68K_ATOMIC __ */