linux驱动学习笔记（2.3) scull模块 init_MUTEX被废除
一、今天在编译ldd3上的scullc的时候，出现如下错误：
刚开始我以为没有包含头文件，然后我就去查2.6.39.1的源代码，结果在所有的符号中都没有发现init_MUTEX,后面在网站上发现了init_MUTEX的定义，如下所示：
源码衔接：
http://lxr.oss.org.cn/source/include/asm-i386/semaphore.h#L89
上面的源码是2.6.16以前的，在2.6.25以后就再也找不到这个宏了，原因我目前不清楚，根据定义就已经可以把问题解决了，将代码改成下面的就行了：
二.排出此问题，出现例外一个问题
原因：在2.6.32 linux/fs/ntfs/ChangeLog 看到如下片段
672.1.26 - Minor bug fixes and updates. 68 69 - Fix a potential overflow in file.c where a cast to s64 was missing in 70 a left shift of a page index. 71 - The struct inode has had its i_sem semaphore changed to a mutex named 72 i_mutex. 73 - We have struct kmem_cache now so use it instead of the typedef 74 kmem_cache_t. (Pekka Enberg) 75 - Implement support for sector sizes above 512 bytes (up to the maximum 76 supported by NTFS which is 4096 bytes). 77 - Do more detailed reporting of why we cannot mount read-write by 78 special casing the VOLUME_MODIFIED_BY_CHKDSK flag.
解决 修改main.c中的 52 53 54行
/* declare one cache pointer: use it for all devices */ //kmem_cache_t *scullc_cache; struct kmem_cache *scullc_cache;
三，问题又来了
home/allen/share/ldd3/src/scull/pipe.c:131:7: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) /home/allen/share/ldd3/src/scull/pipe.c:131:7: note: each undeclared identifier is reported only once for each function it appears in /home/allen/share/ldd3/src/scull/pipe.c:131:3: error: implicit declaration of function ‘signal_pending’ /home/allen/share/ldd3/src/scull/pipe.c:131:3: error: implicit declaration of function ‘schedule’ /home/allen/share/ldd3/src/scull/pipe.c: In function ‘scull_getwritespace’: /home/allen/share/ldd3/src/scull/pipe.c:168:38: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) /home/allen/share/ldd3/src/scull/pipe.c: In function ‘scull_p_write’: /home/allen/share/ldd3/src/scull/pipe.c:219:2: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) /home/allen/share/ldd3/src/scull/pipe.c:223:34: error: ‘SIGIO’ undeclared (first use in this function) /home/allen/share/ldd3/src/scull/pipe.c:223:41: error: ‘POLL_IN’ undeclared (first use in this function) /home/allen/share/ldd3/src/scull/pipe.c: At top level: /home/allen/share/ldd3/src/scull/pipe.c:319:2: error: unknown field ‘ioctl’ specified in initializer /home/allen/share/ldd3/src/scull/pipe.c:319:2: warning: initialization from incompatible pointer type /home/allen/share/ldd3/src/scull/pipe.c: In function ‘scull_p_init’: /home/allen/share/ldd3/src/scull/pipe.c:365:3: error: implicit declaration of function ‘init_MUTEX’ make[2]: *** [/home/allen/share/ldd3/src/scull/pipe.o] Error 1 make[1]: *** [_module_/home/allen/share/ldd3/src/scull] Error 2
TASK_INTERRUPTIBLE找不到，既然前面删除掉了了一个头文件，必然有很多变量找不到，
那就到/usr/src/linux-headers-2.6.32-22-generic下grep一下呗：
最终找到头文件,添加上：
#include <linux/sched.h>
access.c也需要添加上面的头文件。
unknown field ‘ioctl’ specified in initializer
是因为ioctl接口更换的问题。
使用.unlocked_ioctl = scull_ioctl,
error: implicit declaration of function ‘init_MUTEX’
此问题前面也曾提到
四.做如下替换
//int scull_ioctl(struct inode *inode, struct file *filp,
// unsigned int cmd, unsigned long arg)
long scull_ioctl( struct file *filp,
unsigned int cmd, unsigned long arg)
五。到此编译成功
root@ubuntu:/home/allen/share/ldd3/src/scull# make make -C /usr/src/linux-headers-2.6.38-8-generic/ M=/home/allen/share/ldd3/src/scull LDDINC=/home/allen/share/ldd3/src/scull/../include modules make[1]: Entering directory `/usr/src/linux-headers-2.6.38-8-generic' CC [M] /home/allen/share/ldd3/src/scull/main.o CC [M] /home/allen/share/ldd3/src/scull/pipe.o CC [M] /home/allen/share/ldd3/src/scull/access.o LD [M] /home/allen/share/ldd3/src/scull/scull.o Building modules, stage 2. MODPOST 1 modules CC /home/allen/share/ldd3/src/scull/scull.mod.o LD [M] /home/allen/share/ldd3/src/scull/scull.ko make[1]: Leaving directory `/usr/src/linux-headers-2.6.38-8-generic'
参考文章：http://www.cnblogs.com/justinzhang/archive/2011/07/18/2109617.html
