/*! 2017. 6. 3 study -ing */
static int devtmpfsd(void *p)
{
char options[] = "mode=0755";
int *err = p;
/*! sys_unshare는 fork.c의 "SYSCALL_DEFINE1(unshare" 를 참조 */
*err = sys_unshare(CLONE_NEWNS);
if (*err)
goto out;
/*! sys_mount는 fs/namespace.c의 "SYSCALL_DEFINE5(mount" 를 참조 */
*err = sys_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, options);
if (*err)
goto out;
/*! sys_chdir는 fs/open.c 의 "SYSCALL_DEFINE1(chdir" 을 참조 */
sys_chdir("/.."); /* will traverse into overmounted root */
/*! sys_chdir는 fs/open.c 의 "SYSCALL_DEFINE1(chroot" 을 참조 */
sys_chroot(".");
complete(&setup_done);
while (1) {
spin_lock(&req_lock);
while (requests) {
struct req *req = requests;
requests = NULL;
spin_unlock(&req_lock);
while (req) {
struct req *next = req->next;
req->err = handle(req->name, req->mode,
req->uid, req->gid, req->dev);
complete(&req->done);
req = next;
}
spin_lock(&req_lock);
}
__set_current_state(TASK_INTERRUPTIBLE);
spin_unlock(&req_lock);
schedule();
}
return 0;
out:
complete(&setup_done);
return *err;
}
static int devtmpfsd(void *p)
{
char options[] = "mode=0755";
int *err = p;
*err = sys_unshare(CLONE_NEWNS);
printk(KERN_INFO "%s, %s\n", __FILE__,__func__);
if (*err)
goto out;
*err = sys_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, options);
if (*err)
goto out;
sys_chdir("/.."); /* will traverse into overmounted root */
sys_chroot(".");
complete(&setup_done);
while (1) {
spin_lock(&req_lock);
while (requests) {
struct req *req = requests;
requests = NULL;
spin_unlock(&req_lock);
while (req) {
struct req *next = req->next;
req->err = handle(req->name, req->mode, req->dev);
complete(&req->done);
req = next;
}
spin_lock(&req_lock);
}
__set_current_state(TASK_INTERRUPTIBLE);
spin_unlock(&req_lock);
schedule();
}
return 0;
out:
complete(&setup_done);
return *err;
}