linux设备驱动程序该添加哪些头文件

在编写linux设备驱动程序的时候，如果在不参考已有驱动程序的情况下，我们该如何不多不少地用#include包含所需的头文件呢？
下面，来通过一个实验来介绍。
运行环境：Source Insight @ Windows xp
内核代码：Linux 2.6.32
实验代码: 简单ramblock实验

#define DEV_MAJOR 251

static struct gendisk *my_rmbk;
static struct request_queue *my_rq;

DEFINE_SPINLOCK(rmbk_lock);

#define RAMBLOCK_SIZE (1024*1024)

const struct block_device_operations rmbk_fops = {
.owner = THIS_MODULE,
};

static void do_rmbk_request(struct request_queue *q)
{
printk("Do_ramdisk_request\n");
}

static int ramdisk_init(void)
{
/* 注册块设备 */
register_blkdev(DEV_MAJOR, "ramdisk");

/* 分配gendisk结构体*/
my_rmbk = alloc_disk(16);

/* 为块设备准备一个请求队列 */
my_rq = blk_init_queue(do_rmbk_request, &rmbk_lock);

sprintf(my_rmbk, "ramdisk");
my_rmbk->major = DEV_MAJOR;
my_rmbk->first_minor = 0;
my_rmbk->fops = &rmbk_fops;
my_rmbk->queue = my_rq;

set_capacity(my_rmbk, RAMBLOCK_SIZE / 512);

/* 添加分区信息到内核列表 */
add_disk(my_rmbk);

return 0;
}

static void ramdisk_exit(void)
{
del_gendisk(my_rmbk);
blk_cleanup_queue(my_rq);
put_disk(my_rmbk);
unregister_blkdev(DEV_MAJOR, "ramdisk");

return;
}

module_init(ramdisk_init);
module_exit(ramdisk_exit);

MODULE_LICENSE("GPL");

上面是没有写#include语句的源代码，直接编译程序，看会报告那些函数未知

/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:6: warning: data definition has no type or storage class
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:6: warning: type defaults to 'int' in declaration of 'DEFINE_SPINLOCK'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:6: warning: parameter names (without types) in function declaration
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:10: error: variable 'rmbk_fops' has initializer but incomplete type
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:11: error: unknown field 'owner' specified in initializer
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:11: error: 'THIS_MODULE' undeclared here (not in a function)
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:11: warning: excess elements in struct initializer
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:11: warning: (near initialization for 'rmbk_fops')
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c: In function 'do_rmbk_request':
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:16: error: implicit declaration of function 'printk'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c: In function 'ramdisk_init':
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:22: error: implicit declaration of function 'register_blkdev'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:25: error: implicit declaration of function 'alloc_disk'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:25: warning: assignment makes pointer from integer without a cast
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:28: error: implicit declaration of function 'blk_init_queue'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:28: error: 'rmbk_lock' undeclared (first use in this function)
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:28: error: (Each undeclared identifier is reported only once
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:28: error: for each function it appears in.)
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:32: error: implicit declaration of function 'sprintf'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:32: warning: incompatible implicit declaration of built-in function 'sprintf'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:32: error: dereferencing pointer to incomplete type
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:33: error: dereferencing pointer to incomplete type
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:34: error: dereferencing pointer to incomplete type
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:35: error: dereferencing pointer to incomplete type
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:36: error: dereferencing pointer to incomplete type
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:38: error: implicit declaration of function 'set_capacity'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:41: error: implicit declaration of function 'add_disk'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c: In function 'ramdisk_exit':
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:50: error: implicit declaration of function 'del_gendisk'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:51: error: implicit declaration of function 'blk_cleanup_queue'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:52: error: implicit declaration of function 'put_disk'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:53: error: implicit declaration of function 'unregister_blkdev'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c: At top level:
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:58: warning: data definition has no type or storage class
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:58: warning: type defaults to 'int' in declaration of 'module_init'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:58: warning: parameter names (without types) in function declaration
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:59: warning: data definition has no type or storage class
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:59: warning: type defaults to 'int' in declaration of 'module_exit'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:59: warning: parameter names (without types) in function declaration
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:61: error: expected declaration specifiers or '...' before string constant
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:61: warning: data definition has no type or storage class
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:61: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE'
/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.c:61: warning: function declaration isn't a prototype
make[2]: *** [/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk/ramblock.o] Error 1
make[1]: *** [_module_/home/profiles/2440/rootfs/exps_wqkfsc/ramdisk] Error 2
make[1]: Leaving directory `/home/profiles/2440/linux-2.6.32.2'
make: *** [all] Error 2

第6行 warning DECLARE_SPINLOCK
第10行 error rmbk_fops 为struct block_device_operations
第11行 error .owner = THIS_MODULE
第16行 error printk
第22行 error register_blkdev
第25行 error alloc_disk
第28行 error blk_init_queue、rmbk_lock
第32行 error sprintf
第32-36行 error 都是上面引起的连带错误
第38行 error set_capacity
第41行 error add_disk
第50行 error del_gendisk
第51行 error blk_cleanup_queue
第52行 error put_disk
第53行 error unregister_blkdev
第58-59行 warning module_init,module_exit的警告
第61行 error&warning MODULE_LICENSE发出的

先说明一下source insight里面经常用到的两个快捷键
Jump to difinition（跳至定义处）: CTRL+=或者CTRL+左键单击关键词
Lookup reference（查找引用）：CTRL+\ 搜索关键词

步骤：
第6行
DECLARE_SPINLOCK是一个宏，要Lookup reference（查找引用）：#define DECLARE_MUTEX
结果：
Spinlock_types.h (e:\friendly2.6.32.2\include\linux):#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
包含：#define <linux/spinlock_types.h>
第10行
block_device_operations,Jump to difinition，跳到定义处
怎么查看这个文件的路径呢？
Project->Add and Remove Project Files...->右击被选中的文件->Copy List->Copy selected item(s)
e:\friendly2.6.32.2\include\linux\Blkdev.h
包含：#include <linux/blkdev.h>
第11行
THIS_MODULE, 同样的，按住鼠标左键，单击这个词
路径：e:\friendly2.6.32.2\include\linux\Module.h
包含：#include <linux/module.h>
第16行
Jump to difinition: printk
路径: e:\friendly2.6.32.2\include\linux\Kernel.h
包含：#include <linux/kernel.h>
第22行
Jump to difinition: register_blkdev
路径: e:\friendly2.6.32.2\block\Genhd.c
包含：？？？
出现问题了，文件并不在include目录或者子目录中，包含这个文件也没用，而我们用Jump to difinition也只能跳转到Genhd.c
出现int register_blkdev(unsigned int major, const char *name)
这个时候就需要命令Lookup reference（查找引用）。并且搜索的词也是关键，我们需要搜索这个函数的声明，就需要尽量包含整个函数声明的语句。
如int register_blkdev(unsigned int major, const char *name)这整段话搜索的话，很可能不成功，因为包含了变量的名字major, name，不一定能匹配到。
我们应该搜索如"register_blkdev(unsigned int"或者"register_blkdev("这样的关键字，那么就试一试吧。
Fs.h (e:\friendly2.6.32.2\include\linux):extern int register_blkdev(unsigned int, const char *);
Genhd.c (e:\friendly2.6.32.2\block):int register_blkdev(unsigned int major, const char *name)
找到了e:\friendly2.6.32.2\include\linux\Fs.h
那我们就包含#include <linux/fs.h>
第25行
Jump to difinition: alloc_disk
路径: e:\friendly2.6.32.2\block\Genhd.c
找到：struct gendisk *alloc_disk(int minors)
Lookup reference关键字：alloc_disk(int
结果：
Genhd.c (e:\friendly2.6.32.2\block):struct gendisk *alloc_disk(int minors)
Genhd.h (e:\friendly2.6.32.2\include\linux):extern struct gendisk *alloc_disk(int minors);
包含：#include <linux/genhd.h>
我们可以在这个文件里看看，应该和一般的硬盘操作有关的函数都在里面，可以找到
set_capacity、add_disk、del_gendisk、put_disk
第28行
Jump to difinition: blk_init_queue
路径: e:\friendly2.6.32.2\block\Blk-core.c
找到：struct request_queue *blk_init_queue(request_fn_proc *rfn, spinlock_t *lock)
Lookup reference关键字：blk_init_queue(request_fn_proc
结果：
Blk-core.c (e:\friendly2.6.32.2\block):struct request_queue *blk_init_queue(request_fn_proc *rfn, spinlock_t *lock)
Blkdev.h (e:\friendly2.6.32.2\include\linux):extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
包含：#include <linux/blkdev.h>,这里还可以找到blk_cleanup_queue
rmbk_lock，第6行已解决
第32行
Jump to difinition: sprintf
路径: e:\friendly2.6.32.2\lib\Vsprintf.c
找到：int sprintf(char * buf, const char *fmt, ...)
Lookup reference关键字：sprintf(char * buf
结果：
Kernel.h (e:\friendly2.6.32.2\include\linux):extern int sprintf(char * buf, const char * fmt, ...)
Vsprintf.c (e:\friendly2.6.32.2\lib):int sprintf(char * buf, const char *fmt, ...)
包含：#include <linux/kernel.h>，其实和printk在一个文件里面
第32-36行
上面已解决
第38行
set_capacity，第25行已解决
第41行
add_disk，第25行已解决
第50行
del_gendisk，第25行已解决
第51行 error blk_cleanup_queue
第52行
put_disk，第25行已解决
第53行
unregister_blkdev，第28行已解决
第58-59行
Jump to difinition: module_init是找不到的，我们知道它是一个宏
所以只能Lookup reference关键字：#define module_init
结果：
Init.h (e:\friendly2.6.32.2\include\linux):#define module_init(x) __initcall(x);
Init.h (e:\friendly2.6.32.2\include\linux):#define module_init(initfn)
包含：#include <linux/init.h>, module_exit也包含在里面
第61行
同样的只能Lookup reference关键字：MODULE_LICENSE
结果：
Module.h (e:\friendly2.6.32.2\include\linux):#define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
Nand_ecc.c (e:\friendly2.6.32.2\drivers\mtd\nand):#define MODULE_LICENSE(x) /* x */
Pq.h (e:\friendly2.6.32.2\include\linux\raid):#define MODULE_LICENSE(licence)
包含：#include <linux/module.h>

添加上头文件

#include <linux/spinlock_types.h>
#include <linux/blkdev.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/init.h>

再次编译，Finished！ http://hi.baidu.com/tracyangrad/item/f8f40d34265e1bc91a96966b