On Mon, Sep 16, 2013 at 02:19:11PM -0400, Jeff Mahoney wrote: > There are some feature bits that require no offline setup and can > be enabled online. I've only reviewed extended irefs, but there will > probably be more. Each feature bit being set online has to be treated separately regarding safety of the data in flight. You can set extended irefs online, there's only one place where the bit is checked (if the hadlink count overflows the leaf), it's ok to set the bit anytime before or after and it will not break anything. Skinny metadata bit is checked all over the place and I'm not sure it's ok to set it on after some portion of data has been processed in the non-skinny mode. 'default_subvol', lzo are ok, the rest depends on mkfs and can't be modified online at all. So, for skinny metadata it's most likely required to set the bit in a delayed manner and schedule it eg. to post-commit time. The sysfs and ioctl interface looks ok to me. david -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
