On 08/25/2011 05:12 PM, Arnd Bergmann wrote: > The cost of a block device node in the kernel is rather low. Nowadays, > sysfs does not even permanently use inodes for entries, it has a much > more compact internal representation IIRC. > > The main advantage of this approach is not having to set up the > block device at all, it would just be there, which e.g. makes it > possible to put a root file system on it or do something else without > requiring a user space tool to issue an ioctl. Before patch v3, every existing and new UBI volumes were "proxyfied" by ubiblk and it was, indeed, one of our goal to be able to have a rootfs on it. Patch v3 hinders that goal but it could still be achievable by adding a module parameter that would explicitly create a ubiblk device for a UBI volume at boot time. I for one am fine with both solutions (keep the ioctl + add a kernel parameter and throwing the ioctl away and go back "automatically create a ubiblk for each UBI volume"). However, I agree that it doesn't make sense to create a ubiblk device on top of UBI volumes containing, for instance, a ubifs. Best Regards, David. -- David Wagner, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
