On Tue, 27 Aug 2019 11:12:23 +0000 Parav Pandit <[email protected]> wrote:
> > -----Original Message----- > > From: Cornelia Huck <[email protected]> > > Sent: Tuesday, August 27, 2019 3:54 PM > > To: Parav Pandit <[email protected]> > > Cc: [email protected]; Jiri Pirko <[email protected]>; > > [email protected]; [email protected]; [email protected]; linux- > > [email protected]; [email protected] > > Subject: Re: [PATCH 1/4] mdev: Introduce sha1 based mdev alias > > > > On Mon, 26 Aug 2019 15:41:16 -0500 > > Parav Pandit <[email protected]> wrote: > > > > > Whenever a parent requests to generate mdev alias, generate a mdev > > > alias. > > > It is an optional attribute that parent can request to generate for > > > each of its child mdev. > > > mdev alias is generated using sha1 from the mdev name. > > > > Maybe add some motivation here as well? > > > > "Some vendor drivers want an identifier for an mdev device that is shorter > > than > > the uuid, due to length restrictions in the consumers of that identifier. > > > > Add a callback that allows a vendor driver to request an alias of a > > specified > > length to be generated (via sha1) for an mdev device. If generated, that > > alias is > > checked for collisions." > > > I did described the motivation in the cover letter with example and this > design discussion thread. Yes, but adding it to the patch description makes it available in the git history. > I will include above summary in v1. > > > What about: > > > > * @get_alias_length: optional callback to specify length of the alias to > > create > > * Returns unsigned integer: length of the alias to be > > created, > > * 0 to not create an alias > > > Ack. > > > I also think it might be beneficial to add a device parameter here now > > (rather > > than later); that seems to be something that makes sense. > > > Without showing the use, it shouldn't be added. It just feels like an omission: Why should the vendor driver only be able to return one value here, without knowing which device it is for? If a driver supports different devices, it may have different requirements for them. > > > > * Parent device that support mediated device should be registered with > > mdev > > > * module with mdev_parent_ops structure. > > > **/ > > > @@ -92,6 +95,7 @@ struct mdev_parent_ops { > > > long (*ioctl)(struct mdev_device *mdev, unsigned int cmd, > > > unsigned long arg); > > > int (*mmap)(struct mdev_device *mdev, struct vm_area_struct > > *vma); > > > + unsigned int (*get_alias_length)(void); > > > }; > > > > > > /* interface for exporting mdev supported type attributes */ >
