libkern/OSCacheControl.h

Prepare memory for execution. This should be called after writing machine instructions to memory, before executing them. It syncs the dcache and icache. On IA32 processors this function is a NOP, because no synchronization is required.

#define kCacheFunctionPrepareForExecution 1

Flush data cache(s). This ensures that cached data makes it all the way out to DRAM, and then removes copies of the data from all processor caches. It can be useful when dealing with cache incoherent devices or DMA.

#define kCacheFunctionFlushDcache 2

__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_2_0)
int sys_cache_control(int function, void *start, size_t len)

perform one of the above cache functions:

__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_2_0)
void sys_icache_invalidate(void *start, size_t len)

equivalent to sys_cache_control(kCacheFunctionPrepareForExecution):

__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_2_0)
void sys_dcache_flush(void *start, size_t len)

equivalent to sys_cache_control(kCacheFunctionFlushDcache):