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Originally nvme multipath would update/change the size of the multipath
device according to the underlying path devices.
With this patch the size of the multipath device will _not_ change if
there
is a change on the underlying devices.
Yes, it will. Take a close look at nvme_update_disk_info and how it is
called.
Okay, then: What would be the correct way of handling a size update for
NVMe multipath?
Assuming we're getting an AEN for each path signalling the size change
(or a controller reset leading to a size change).
So if we're updating the size of the multipath device together with the
path device at the first AEN/reset we'll end up with the other paths
having a different size than the multipath device (and the path we've
just been updating).
- Do we care, or cross fingers and hope for the best?
- Shouldn't we detect the case where we won't get a size update for the
other paths, or, indeed, we have a genuine device size mismatch due to a
misconfiguration on the target?
IE shouldn't we have a flag 'size update pending' for the other paths,,
to take them out ouf use temporarily until the other AENs/resets have
been processed?
the mpath device will take the minimum size from all the paths, that is
what blk_stack_limits does. When the AEN for all the paths will arrive
the mpath size will update.
Not sure how this is different than what we have today...
