xen/blkback: Fix the inhibition to map pages when discarding sector ranges.

The 'operation' parameters are the ones provided to the bio layer while
the req->operation are the ones passed in between the backend and
frontend. We used the wrong 'operation' value to squash the
call to map pages when processing the discard operation resulting
in an hypercall that did nothing. Lets guard against going in the
mapping function by checking for the proper operation type.

CC: Li Dongyang <lidongyang@novell.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Konrad Rzeszutek Wilk 2011-10-10 00:47:49 -04:00
parent 5c62cb4860
commit 64391b2536

View File

@ -707,8 +707,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
* the hypercall to unmap the grants - that is all done in
* xen_blkbk_unmap.
*/
if (operation != BLKIF_OP_DISCARD &&
xen_blkbk_map(req, pending_req, seg))
if (operation == REQ_DISCARD && xen_blkbk_map(req, pending_req, seg))
goto fail_flush;
/*