From: Eric Blake <ebl...@redhat.com> Our .bdrv_has_zero_init_truncate can detect when the remote side always zero fills; we can reuse that same knowledge to implement BDRV_REQ_ZERO_WRITE by ignoring it when the server gives it to us for free.
Signed-off-by: Eric Blake <ebl...@redhat.com> Message-Id: <20200428202905.770727-7-ebl...@redhat.com> Reviewed-by: Richard W.M. Jones <rjo...@redhat.com> Signed-off-by: Kevin Wolf <kw...@redhat.com> --- block/ssh.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/block/ssh.c b/block/ssh.c index 9eb33df859..f9e08a4900 100644 --- a/block/ssh.c +++ b/block/ssh.c @@ -883,6 +883,10 @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags, /* Go non-blocking. */ ssh_set_blocking(s->session, 0); + if (s->attrs->type == SSH_FILEXFER_TYPE_REGULAR) { + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; + } + qapi_free_BlockdevOptionsSsh(opts); return 0; -- 2.25.3