Scull在2.6.32.2内核中的编译解决方案

  LDD3作为从事驱动开发工作人员的必要参考资料，认真研究书中的附带源码具有很高的参考价值，但由于代码基于2.6.10内核，部分内核API较老，导致在2.6.32.2等较新内核上编译不能通过，由于工作需要，特花了一段时间进行整理，本篇文章对示例源码中的第一个驱动程序SCULL进行整理，供各位同仁参考：

1、修改Makefile的第24行：

   

如果是基于PC，则

KERNELDIR ?= /lib/modules/$(shell uname -r)/build(我的PC中linux内核是2.6.32版本)

如果是基于ARM，则改变为： KERNELDIR ?= ../../../../linux/linux-2.6.32.2(arm开发板上所需内核的源码目录)

2、进入scull目录，执行make，有如下错误：

make -C /lib/modules/2.6.32-28-generic/build M=/media/orientation/driver/ldd3/examples/scull LDDINC=/media/orientation/driver/ldd3/examples/scull/../include modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.32-28-generic'
scripts/Makefile.build:49: *** CFLAGS was changed in "/media/orientation/driver/ldd3/examples/scull/Makefile". Fix it to use EXTRA_CFLAGS. Stop.
make[1]: *** [_module_/media/orientation/driver/ldd3/examples/scull] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-28-generic'
make: *** [modules] Error 2

3、根据错误提示，修改Makefile中12、13行代码如下：

EXTRA_CFLAGS += $(DEBFLAGS)
EXTRA_CFLAGS += -I$(LDDINC)

4、接着make，错误如下：

make -C /lib/modules/2.6.32-28-generic/build M=/media/orientation/driver/ldd3/examples/scull LDDINC=/media/orientation/driver/ldd3/examples/scull/../include modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.32-28-generic'
  CC [M] /media/orientation/driver/ldd3/examples/scull/main.o
/media/orientation/driver/ldd3/examples/scull/main.c:17:26: error: linux/config.h: No such file or directory
make[2]: *** [/media/orientation/driver/ldd3/examples/scull/main.o] Error 1
make[1]: *** [_module_/media/orientation/driver/ldd3/examples/scull] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-28-generic'
make: *** [modules] Error 2
root@ubuntu:/media/orientation/driver/ldd3/examples/scull# vim Makefile
root@ubuntu:/media/orientation/driver/ldd3/examples/scull# make
make -C /lib/modules/2.6.32-28-generic/build M=/media/orientation/driver/ldd3/examples/scull LDDINC=/media/orientation/driver/ldd3/examples/scull/../include modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.32-28-generic'
  CC [M] /media/orientation/driver/ldd3/examples/scull/main.o
/media/orientation/driver/ldd3/examples/scull/main.c:17:26: error: linux/config.h: No such file or directory
make[2]: *** [/media/orientation/driver/ldd3/examples/scull/main.o] Error 1
make[1]: *** [_module_/media/orientation/driver/ldd3/examples/scull] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-28-generic

5、根据提示，查看2.6.32.2源码发现linux/config.h文件不存在，直接在main.c里将他屏蔽，接着编译，仍有错误:

make -C /lib/modules/2.6.32-28-generic/build M=/media/orientation/driver/ldd3/examples/scull LDDINC=/media/orientation/driver/ldd3/examples/scull/../include modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.32-28-generic'
  CC [M] /media/orientation/driver/ldd3/examples/scull/main.o
  CC [M] /media/orientation/driver/ldd3/examples/scull/pipe.o
/media/orientation/driver/ldd3/examples/scull/pipe.c: In function ‘scull_p_read’:
/media/orientation/driver/ldd3/examples/scull/pipe.c:131: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function)
/media/orientation/driver/ldd3/examples/scull/pipe.c:131: error: (Each undeclared identifier is reported only once
/media/orientation/driver/ldd3/examples/scull/pipe.c:131: error: for each function it appears in.)
/media/orientation/driver/ldd3/examples/scull/pipe.c:131: error: implicit declaration of function ‘signal_pending’
/media/orientation/driver/ldd3/examples/scull/pipe.c:131: error: implicit declaration of function ‘schedule’
/media/orientation/driver/ldd3/examples/scull/pipe.c: In function ‘scull_getwritespace’:
/media/orientation/driver/ldd3/examples/scull/pipe.c:168: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function)
/media/orientation/driver/ldd3/examples/scull/pipe.c: In function ‘scull_p_write’:
/media/orientation/driver/ldd3/examples/scull/pipe.c:219: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function)
/media/orientation/driver/ldd3/examples/scull/pipe.c:223: error: ‘SIGIO’ undeclared (first use in this function)
/media/orientation/driver/ldd3/examples/scull/pipe.c:223: error: ‘POLL_IN’ undeclared (first use in this function)
make[2]: *** [/media/orientation/driver/ldd3/examples/scull/pipe.o] Error 1
make[1]: *** [_module_/media/orientation/driver/ldd3/examples/scull] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-28-generic'
make: *** [modules] Error 2

6、根据提示，TASK_INTERRUPTIBLE没有声明，我们在源码里面搜索，发现该宏定义在中，故在pipe.c中加入该头文件，接着make：

make -C /lib/modules/2.6.32-28-generic/build M=/media/orientation/driver/ldd3/examples/scull LDDINC=/media/orientation/driver/ldd3/examples/scull/../include modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.32-28-generic'
  CC [M] /media/orientation/driver/ldd3/examples/scull/pipe.o
  CC [M] /media/orientation/driver/ldd3/examples/scull/access.o
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_u_open’:
/media/orientation/driver/ldd3/examples/scull/access.c:106: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c:107: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c:114: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_w_available’:
/media/orientation/driver/ldd3/examples/scull/access.c:165: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c:166: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_w_open’:
/media/orientation/driver/ldd3/examples/scull/access.c:179: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function)
/media/orientation/driver/ldd3/examples/scull/access.c:179: error: (Each undeclared identifier is reported only once
/media/orientation/driver/ldd3/examples/scull/access.c:179: error: for each function it appears in.)
/media/orientation/driver/ldd3/examples/scull/access.c:179: error: implicit declaration offunction ‘signal_pending’
/media/orientation/driver/ldd3/examples/scull/access.c:179: error: implicit declaration offunction ‘schedule’
/media/orientation/driver/ldd3/examples/scull/access.c:184: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_w_release’:
/media/orientation/driver/ldd3/examples/scull/access.c:205: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function)
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_c_open’:
/media/orientation/driver/ldd3/examples/scull/access.c:277: error: dereferencing pointer to incomplete type
/media/orientation/driver/ldd3/examples/scull/access.c:281: error: dereferencing pointer to incomplete type
make[2]: *** [/media/orientation/driver/ldd3/examples/scull/access.o] Error 1
make[1]: *** [_module_/media/orientation/driver/ldd3/examples/scull] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-28-generic'
make: *** [modules] Error 2

7、根据提示，同上所述，我们需要在access.c中加入头文件，接着编译：

make -C /lib/modules/2.6.32-28-generic/build M=/media/orientation/driver/ldd3/examples/scull LDDINC=/media/orientation/driver/ldd3/examples/scull/../include modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.32-28-generic'
  CC [M] /media/orientation/driver/ldd3/examples/scull/access.o
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_u_open’:
/media/orientation/driver/ldd3/examples/scull/access.c:106: error: ‘struct task_struct’ has no member named ‘uid’
/media/orientation/driver/ldd3/examples/scull/access.c:107: error: ‘struct task_struct’ has no member named ‘euid’
/media/orientation/driver/ldd3/examples/scull/access.c:114: error: ‘struct task_struct’ has no member named ‘uid’
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_w_available’:
/media/orientation/driver/ldd3/examples/scull/access.c:165: error: ‘struct task_struct’ has no member named ‘uid’
/media/orientation/driver/ldd3/examples/scull/access.c:166: error: ‘struct task_struct’ has no member named ‘euid’
/media/orientation/driver/ldd3/examples/scull/access.c: In function ‘scull_w_open’:
/media/orientation/driver/ldd3/examples/scull/access.c:184: error: ‘struct task_struct’ has no member named ‘uid’
make[2]: *** [/media/orientation/driver/ldd3/examples/scull/access.o] Error 1
make[1]: *** [_module_/media/orientation/driver/ldd3/examples/scull] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-28-generic'
make: *** [modules] Error 2

8、根据提示，错误在于task_struct结构体没有uid，euid成员变量，查看源码发现struct task_struct定义在include/linux/sched.h中，确实没有这两个成员，逐个成员分析发现，这两个成员在2.6.32内核中放在const struct cred *cred成员中了，所以，我们尝试将所有出现错误的地方做如下改动：

current->uid 修改为 current->cred->uid
current->euid 修改为 current->cred->euid

9、接着make，发现成功编译。

通过这个例子，我们能真正深刻体会linux内核仍旧处于不断变化之中，需要我们不断去学习！

    enjoy it！