1/* SPDX-License-Identifier: GPL-2.0 */ 2#if defined(__i386__) || defined(__x86_64__) 3#define barrier() asm volatile("" ::: "memory") 4#define virt_mb() __sync_synchronize() 5#define virt_rmb() barrier() 6#define virt_wmb() barrier() 7/* Atomic store should be enough, but gcc generates worse code in that case. */ 8#define virt_store_mb(var, value) do { \ 9 typeof(var) virt_store_mb_value = (value); \ 10 __atomic_exchange(&(var), &virt_store_mb_value, &virt_store_mb_value, \ 11 __ATOMIC_SEQ_CST); \ 12 barrier(); \ 13} while (0); 14/* Weak barriers should be used. If not - it's a bug */ 15# define mb() abort() 16# define dma_rmb() abort() 17# define dma_wmb() abort() 18#else 19#error Please fill in barrier macros 20#endif 21 22