cluster/ec: Fix pre-op xattrop management

Multiple pre-op xattrop can be simultaneously being processed. On the cbk
it was checked if the fop was waiting for some specific data (like size and
version) and, if so, it was assumed that this answer should contain that
data.

This is not true, since a fop can be waiting for some data, but it may come
from the xattrop of another fop.

This patch differentiates between needing some information and providing it.

This is related to parallel writes. Disabling them fixed the problem, but
also prevented concurrent reads. A change has been made so that disabling
parallel writes still allows parallel reads.

Backport of:
> BUG: 1578325

Fixes: bz#1582056
Change-Id: I74772ad6b80b7b37805da93d5ec3ae099e96b041
Signed-off-by: Xavi Hernandez <xhernandez@redhat.com>

0 files changed, 0 insertions, 0 deletions