[PATCH v4 06/40] fs: add mount_setattr()

[Christian Brauner]

On Mon, Dec 07, 2020 at 06:14:56PM +0100, Christoph Hellwig wrote:
> > +	switch (attr->propagation) {
> > +	case 0:
> > +		kattr->propagation = 0;
> > +		break;
> > +	case MS_UNBINDABLE:
> > +		kattr->propagation = MS_UNBINDABLE;
> > +		break;
> > +	case MS_PRIVATE:
> > +		kattr->propagation = MS_PRIVATE;
> > +		break;
> > +	case MS_SLAVE:
> > +		kattr->propagation = MS_SLAVE;
> > +		break;
> > +	case MS_SHARED:
> > +		kattr->propagation = MS_SHARED;
> > +		break;
> > +	default:
> > +		return -EINVAL;
> > +	}
> 
> This can be shortened to:
> 
> #define MOUNT_SETATTR_PROPAGATION_FLAGS \
> 	(MS_UNBINDABLE | MS_PRIVATE | MS_SLAVE | MS_SHARED)
> 
> 	if (attr->propagation & ~MOUNT_SETATTR_PROPAGATION_FLAGS)
> 		return -EINVAL;
> 	if (hweight32(attr->propagation & MOUNT_SETATTR_PROPAGATION_FLAGS) > 1)
> 		return -EINVAL;
> 	kattr->propagation = attr->propagation;

Looks good! I've applied that.

> 
> > +asmlinkage long sys_mount_setattr(int dfd, const char __user *path, unsigned int flags,
> 
> Overly long line.

Folded after @path now.

> 
> Otherwise looks good:
> 
> Reviewed-by: Christoph Hellwig <hch at lst.de>

Thanks, I've pushed out the changes to:
https://git.kernel.org/brauner/h/idmapped_mounts
the original v4 can now be found at:
https://git.kernel.org/brauner/h/idmapped_mounts_v4

You want a v5 with the changes you requested before you continue
reviewing? Otherwise I'll just let you go through v4.

Thanks!
Christian