On Wed, Apr 27, 2016 at 08:20:33PM +0200, Matias Bjørling wrote:
>
>
> On 04/27/2016 07:41 PM, Greg KH wrote:
> > On Wed, Apr 27, 2016 at 10:18:57AM -0700, Simon A. F. Lund wrote:
> > > --- a/include/linux/lightnvm.h
> > > +++ b/include/linux/lightnvm.h
> > > @@ -174,6 +174,7 @@ struct nvm_id_group {
> > > u16 cpar;
> > >
> > > struct nvm_id_lp_tbl lptbl;
> > > + struct kobject kobj;
> > > };
> > >
> > > struct nvm_addr_format {
> > > @@ -205,6 +206,7 @@ struct nvm_target {
> > > struct list_head list;
> > > struct nvm_tgt_type *type;
> > > struct gendisk *disk;
> > > + struct kobject kobj;
> > > };
> > >
> > > struct nvm_tgt_instance {
> > > @@ -360,6 +362,8 @@ struct nvm_dev {
> > >
> > > struct mutex mlock;
> > > spinlock_t lock;
> > > +
> > > + struct kobject kobj;
> > > };
> > >
> > > static inline struct ppa_addr generic_to_dev_addr(struct nvm_dev *dev,
> >
> > Never use "raw" kobjects in a driver for a device. You just guaranteed
> > that userspace tools will not see these devices or attributes, which
> > implies you didn't really test this using libudev :(
> >
> > Please use real devices, attached to the real devices your disks already
> > have in the tree.
> >
> > And are you sure you didn't just mess up your reference counting by
> > now having the lifecycle of these structures be dictated by the kobject?
> >
> > thanks,
> >
> > greg k-h
> >
>
> Hi Greg,
>
> Thanks for the feedback.
>
> lightnvm doesn't have anything to hook up with in the /dev/block/* until a
> device is exposed through a target. A device goes into a staging area, and
> then later is configured to expose a block device.
>
> In the case of NVMe device driver, the driver brings up a device, identifies
> it as a lightnvm device, then calls nvm_register and registers the device.
> It skips the registration as a block device.
But you could register it with sysfs at this point in time, giving you
a place in the device tree. Which would be good.
> At the nvm_register point, the user can list the available devices through
> an ioctl, and then choose a target to put on top. The target will then
> expose it as a block device.
Then move the device at this point in time.
> This might not be the ideal way. I like your input on what would be the
> proper way to expose such a device.
See above.
thanks,
greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-block" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
