linux内核之 phys_to_virt

[b]phys_to_virt是将已经映射的物理内存的地址转换为虚拟地址[/b]

函数定义:

static inline void *phys_to_virt(unsigned long x)

{

return (void*)(__phys_to_virt((unsigned long)(x)));

}

#define__phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)

#ifdef CONFIG_CPU_S3C2400

#definePHYS_OFFSET (0x0C000000UL)

#else

#definePHYS_OFFSET () //2410应该使用这个偏移地址

#endif

#definePAGE_OFFSET (0xc0000000UL) //3G处



由此可知物理内存与内核虚拟地址3G开始处一一对应.