alloc_pages()用法

#include <linux/module.h>
#include <linux/init.h>
#include <asm/atomic.h>
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/string.h>

#define err(msg) printk(KERN_ALERT "%s\n", msg)

static int main_init(void)
{
        struct page *page;
        void *address;
        char data[] = "hello linux";

        page = alloc_pages(GFP_KERNEL, 0);
        if (!page)
        {
                err("alloc_pages");
                return -1;
        }

        address = page_address(page);
        if (!address)
        {
                err("page_address");
                goto err;
        }

        memcpy(address, data, strlen(data));
        printk(KERN_ALERT "%s\n", (char *)address);
        free_pages((unsigned long)address, 0);

        return 0;
err:
        free_pages((unsigned long)page, 0);
        return -1;
}

static void main_exit(void)
{
}

module_init(main_init);
module_exit(main_exit);

MODULE_LICENSE("GPL");