On 05/04/2018 05:40 AM, Vladimir Sementsov-Ogievskiy wrote:
04.05.2018 01:26, Eric Blake wrote:
The NBD spec is proposing a relaxation of NBD_CMD_BLOCK_STATUS
where a server may have the final extent per context give a
length beyond the original request, if it can easily prove that
subsequent bytes have the same status, on the grounds that a
client can take advantage of this information for fewer block
status requests. Since qemu 2.12 as a client always sends
NBD_CMD_FLAG_REQ_ONE, and rejects a server that sends extra
length, the upstream NBD spec will probably limit this behavior
to clients that don't request REQ_ONE semantics; but it doesn't
hurt to relax qemu to always be permissive of this server
behavior, even if it continues to use REQ_ONE.
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
block/nbd-client.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
with s/==/=/
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Thanks; queuing the fixed patch on my NBD tree. Also, I think this
deserves to go in a stable release, to minimize the chance that we choke
on an incompatible server, so:
CC: qemu-sta...@nongnu.org
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
