Re: [PATCH for-next] RDMA/core: Assign the name of device when allocating ib_device

[Leon Romanovsky <leon@kernel.org>]

On Tue, Apr 28, 2020 at 08:00:29AM +0000, liweihang wrote:
> On 2020/4/27 20:03, Leon Romanovsky wrote:
> >>>>  /**
> >>>>   * _ib_alloc_device - allocate an IB device struct
> >>>>   * @size:size of structure to allocate
> >>>> + * @name: unique string device name. This may include a '%' which will
> >>> It looks like all drivers are setting "%" in their name and "name" can
> >>> be changed to be "prefix".
> >> Does hfi? I thought the name was forced there for some port swapped
> >> reason?
> > This patch doesn't touch HFI, nothing prohibits from us to make this
> > conversion work for all drivers except HFI and for the HFI add some
> > different callback. There is no need to make API harder just because
> > one driver needs it.
> >
> > Thanks
> >
> >> Jason
>
> Hi Jason and Leon,
>
> I missed some codes related to assign_name() in this series including
> hfi/qib as Shiraz pointed. And I found a "name" without a "%" in following
> funtions in core/nldev.c, and ibdev_name will be used for rxe/siw later.
>
> 	static int nldev_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
> 				  struct netlink_ext_ack *extack)
> 	{
> 		...
>
> 		nla_strlcpy(ibdev_name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
> 			    sizeof(ibdev_name));
> 		if (strchr(ibdev_name, '%') || strlen(ibdev_name) == 0)
> 			return -EINVAL;
>
> 		...
> 	}
>
> I'm not familiar with these codes, but I think the judgment in assign_name()
> is for the situaion like above.
>
> 	if (strchr(name, '%'))
> 		ret = alloc_name(device, name);
> 	else
> 		ret = dev_set_name(&device->dev, name);
>
> So is it a better idea to keep using "name" instead of "prefix"?

nldev_newlink() doesn't call to ib_alloc_device() and alloc_name(). The
check pointed by you is for the user input.

>
> Thanks
> Weihang