locking/atomic: m68k: add preprocessor symbols

Some atomics can be implemented in several different ways, e.g.
FULL/ACQUIRE/RELEASE ordered atomics can be implemented in terms of
RELAXED atomics, and ACQUIRE/RELEASE/RELAXED can be implemented in terms
of FULL ordered atomics. Other atomics are optional, and don't exist in
some configurations (e.g. not all architectures implement the 128-bit
cmpxchg ops).

Subsequent patches will require that architectures define a preprocessor
symbol for any atomic (or ordering variant) which is optional. This will
make the fallback ifdeffery more robust, and simplify future changes.

Add the required definitions to arch/m68k.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230605070124.3741859-9-mark.rutland@arm.com
This commit is contained in:
Mark Rutland 2023-06-05 08:01:05 +01:00 committed by Peter Zijlstra
parent 8ad17f2183
commit e50f06ce2d

View file

@ -106,6 +106,11 @@ static inline int arch_atomic_fetch_##op(int i, atomic_t * v) \
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
#define arch_atomic_add_return arch_atomic_add_return
#define arch_atomic_sub_return arch_atomic_sub_return
#define arch_atomic_fetch_add arch_atomic_fetch_add
#define arch_atomic_fetch_sub arch_atomic_fetch_sub
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
@ -115,6 +120,10 @@ ATOMIC_OPS(and, &=, and)
ATOMIC_OPS(or, |=, or)
ATOMIC_OPS(xor, ^=, eor)
#define arch_atomic_fetch_and arch_atomic_fetch_and
#define arch_atomic_fetch_or arch_atomic_fetch_or
#define arch_atomic_fetch_xor arch_atomic_fetch_xor
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN