Commit dbe5c58f authored by Peter Lieven's avatar Peter Lieven Committed by Paolo Bonzini
Browse files

block/iscsi: allow fall back to WRITE SAME without UNMAP 



if the iscsi driver receives a write zeroes request with
the BDRV_REQ_MAY_UNMAP flag set it fails with -ENOTSUP
if the iscsi target does not support WRITE SAME with
UNMAP. However, the BDRV_REQ_MAY_UNMAP is only a hint
and writing zeroes with WRITE SAME will still be
better than falling back to writing zeroes with WRITE16.

Signed-off-by: default avatarPeter Lieven <pl@kamp.de>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent d383c625

block/iscsi.c

+6 −5
Original line number Diff line number Diff line
@@ -809,13 +809,14 @@ coroutine_fn iscsi_co_write_zeroes(BlockDriverState *bs, int64_t sector_num, 
        return -EINVAL;

    }



    if (!(flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->has_write_same) {

        /* WRITE SAME without UNMAP is not supported by the target */

        return -ENOTSUP;

    if ((flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->lbp.lbpws) {

        /* WRITE SAME with UNMAP is not supported by the target,

         * fall back and try WRITE SAME without UNMAP */

        flags &= ~BDRV_REQ_MAY_UNMAP;

    }



    if ((flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->lbp.lbpws) {

        /* WRITE SAME with UNMAP is not supported by the target */

    if (!(flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->has_write_same) {

        /* WRITE SAME without UNMAP is not supported by the target */

        return -ENOTSUP;

    }