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: Peter Lieven <p...@kamp.de>
---
block/iscsi.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/block/iscsi.c b/block/iscsi.c
index 0819945..5fbee82 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -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;
}
--
1.7.9.5
