igb_down from bottom half context

I  have kernel timer which  check for flag.

if(flag ) {
          igb_down(adapter);
 } else {
         igb_up(adapter);
 }


I could see a kernel crash; because  there are a lot of  msleep() in
igb_down function.

#define msleep(x)    do { set_current_state(TASK_UNINTERRUPTIBLE); \
                                schedule_timeout((x * HZ)/1000 + 2); \
                              } while (0)

sleep() is called from bottom half context; this is the cause of kernel crash.

1) Since timer call back dont have process context associated with it;
i think , "current" points to the last preempted task ?
2) How can i introduce delays in interrupt context to avoid the kernel
crash. mdelay()  will work ?
3) is there any better mechanism to do this job ?

Thanks,
Ratheesh