On 3/8/12 5:39 PM, Dave Chinner wrote: > On Thu, Mar 08, 2012 at 10:38:32AM -0600, Ben Myers wrote: >> On Thu, Mar 08, 2012 at 09:42:21AM -0600, Eric Sandeen wrote: >>> So, after thinking about this (and talking on irc) some more, I'm >>> not convinced that a feature flag is the way to go. >>> >>> If we set a feature flag, suddenly old filesystems with 64-bit >>> inodes will grow a new feature, and this will force a userspace >>> upgrade - but there is no real new feature. This seems like a bad >>> idea. My original patch (which Dave responded to with this one) >>> simply made inode64 default, with no feature flags. >>> >>> Unless someone has a really compelling argument for the flag, >>> I'm thinking this is the wrong approach after all. >>> >>> Perhaps I should resend the just-make-it-default patch. >>> >>> Comments? >> >> Ew! Forcing a userspace upgrade is not desireable. Since we would only >> want to set the feature bit if userspace were already upgraded, and only >> if there are 64 bit inos... How about two bits: one is set by mkfs and >> checked by the kernel to see if it is ok to set the other. ;) >> >> The first bit could also act as 'now its ok to default to inode64'. > > Too complex, IMO. Just add an xfs_admin command to set the inode64 > feature bit. That then overrides the inode64/inode32 mount option, > and guarantees that the user has already upgraded userspace. > > i.e. the mount options are only valid if the feature bit it not set, > and the feature bit can only be set via xfs_admin after a userspace > upgrade. Kernels that don't understand the feature bit will refuse > to mount, keeping in line with the current practise of requiring > both kernel and userspace upgrades to occur in step to use new > features.... Yep, I think that's the right path forward (had been thinking along these lines too, today). Thanks, -Eric > Cheers, > > Dave. _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
