Subject: [patch 3/4] timerfd: Implement timerfd_ioctl method to restore timerfd_ctx::ticks

From: [email-masked] (Cyrill Gorcunov)
Date: Wed, 2 Jul 2014 21:04:16 +0400

On Wed, Jul 02, 2014 at 12:49:51PM -0400, Christopher Covington wrote:
> >  
> > +#ifdef CONFIG_CHECKPOINT_RESTORE
> > +static long timerfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> > +{
> > +	struct timerfd_ctx *ctx = file->private_data;
> > +	int ret = 0;
> > +
> > +	switch (cmd) {
> > +	case TFD_IOC_SET_TICKS: {
> > +		u64 ticks;
> > +
> > +		if (get_user(ticks, (u64 __user *)arg))
> 
> 64-bit get_user is currently unsupported on ARM, although it appears work is
> ongoing [1].
> 
> 1. https://lkml.org/lkml/2014/6/17/260

Thanks for info, Christopher! What arm camp is using then, copy-from-user?