Below is a sample module to compile (my_module.c):
#include linux/init.h
#include linux/module.h
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Oguzhan Ozmen");
MODULE_DESCRIPTION("My simple Hello World module");
static int module_init(void){
printk(KERN_ALERT "Hello World\n");
return 0; // success
}
static void __exit module_exit(void){
printk(KERN_ALERT "Goodbye\n");
}
module_init(module_init);
module_exit(module_exit);
Within the directory where my_module.c resides in, create a Makefile whose content is as follows:
obj-m += monitor_blockio.o
Then, generate the kernel object file (.ko) using the following command:
make -C [build_dir] M=$PWD modules
Here,
[build_dir]
stands for the directory which contains the necessary files to build new kernel modules:
- Makefile
- .config
- module.symVers (module symbol information)
- kernel header files (include/ and include/asm)
In general, [build_dir]
is:
- /lib/modules/$(uname -r)/build OR
- /usr/src/packages/BUILD/kernel-$(uname -r)
(assuming that you are using a distro compiled kernel)
