c - 如何打印 void * ioremap_nocache() 的返回值？

Question

我如何用 printk 打印函数 ioremap_nocache 返回的地址的值？

void * ioremap_nocache (unsigned long phys_addr, unsigned long size);  

http://mirror.linux.org.au/linux-mandocs/2.6.4-cset-20040312_2111/ioremap_nocache.html

我需要知道存储的虚拟地址的值，以调试打开、读取和写入的函数。

Answer 1

You can use both %lu or %p to print a pointer. They have different representation

void *pointer = ioremap_nocache(phys_addr, size);
unsigned long cast = pointer;
printk("%lu - %p", cast, pointer);    // '15294563 - 0x499602d2'

This work also with printf()

Answer 2

您可以使用以下

unsigned long x = ioremap_nocache (addr, size);  

printk(" %lu",x);