ldd3 源码编译之 scull 字符设备驱动

编译环境Ubuntu12.04   linux-3.2

1. 
   

   make -C /lib/modules/3.2.0/build M=/home/wrk/works/drivers/ldd3/examples/scull LDDINC=/home/wrk/works/drivers/ldd3/examples/scull/../include modules
   make[1]: Entering directory `/home/wrk/works/drivers/linux-kernel/linux-3.2'
   scripts/Makefile.build:49: *** CFLAGS was changed in "/home/wrk/works/drivers/ldd3/examples/scull/Makefile". Fix it to use ccflags-y.  Stop.

   如提示所示：在Makefile中用ccflags-y替换CFLAGS                                             
2. 
   

   /home/wrk/works/drivers/ldd3/examples/scull/main.c:17:26: fatal error: linux/config.h: No such file or directory
   compilation terminated.
   make[2]: *** [/home/wrk/works/drivers/ldd3/examples/scull/main.o] Error 1

   直接删掉config.h这行
3. 
   

   /home/wrk/works/drivers/ldd3/examples/scull/main.c:556:2: error: unknown field ‘ioctl’ specified in initializer
   /home/wrk/works/drivers/ldd3/examples/scull/main.c:556:2: warning: initialization from incompatible pointer type [enabled by default]

   用unlocded_ioctl替换ioctl
4. 
   

   /home/wrk/works/drivers/ldd3/examples/scull/main.c:652:3: error: implicit declaration of function ‘init_MUTEX’ [-Werror=implicit-function-declaration]
   cc1: some warnings being treated as errors

   解决方案：在相应文件开始添加
   

   #include <linux/semaphore.h>
   #define init_MUTEX(a) sema_init(a,1)
   #define init_MUTEX_LOCKED(a) sema_init(a,0)

5. 
   

   /home/wrk/works/drivers/ldd3/examples/scull/pipe.c: In function ‘scull_p_read’:
   /home/wrk/works/drivers/ldd3/examples/scull/pipe.c:131:7: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function)
   /home/wrk/works/drivers/ldd3/examples/scull/pipe.c:131:7: note: each undeclared identifier is reported only once for each function it appears in
   /home/wrk/works/drivers/ldd3/examples/scull/pipe.c:131:3: error: implicit declaration of function ‘signal_pending’ [-Werror=implicit-function-declaration]
   /home/wrk/works/drivers/ldd3/examples/scull/pipe.c:131:3: error: implicit declaration of function ‘schedule’ [-Werror=implicit-function-declaration]

   在pipe.c和access.c中添加“#include <linux/sched.h>"
6. 
   

   /home/wrk/works/drivers/ldd3/examples/scull/access.c:101:34: error: ‘SPIN_LOCK_UNLOCKED’ undeclared here (not in a function)

   原因：新版本内核中，SPIN_LOCK_UNLOCKED被移除

   建议：使用DEFINE_SPINLOCK(lock)宏来替代

   /*static spinlock_t scull_w_lock = SPIN_LOCK_UNLOCKED;*改成下面到方式/
   static DEFINE_SPINLOCK(scull_w_lock);

7. 
   

   /home/wrk/works/drivers/ldd3/examples/scull/access.c:111:29: error: ‘struct task_struct’ has no member named ‘uid’
   /home/wrk/works/drivers/ldd3/examples/scull/access.c:112:29: error: ‘struct task_struct’ has no member named ‘euid’
   /home/wrk/works/drivers/ldd3/examples/scull/access.c:119:26: error: ‘struct task_struct’ has no member named ‘uid’

   struct task_struct定义在include/linux/sched.h中，原来task_struct结构体定义有所改动，将uid和euid等挪到 cred中，见include/linux/sched.h和include/linux/cred.h。
   
   因此只需要将报error的代码做如下修改
   current->uid 修改为 current->cred->uid
   current->euid 修改为 current->cred->euid
   
   然后make，就大功告成了