[PATCH] srp: fix fmr error handling

srp_unmap_data assumes req->fmr is NULL if the request is not mapped, so we
must clean it out in case of an error.

Signed-off-by: Vu Pham <vu@mellanox.com>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/infiniband/ulp/srp/ib_srp.c

@@ -618,6 +618,7 @@ static int srp_map_fmr(struct srp_device *dev, struct scatterlist *scat,
 					dma_pages, page_cnt, &io_addr);
 	if (IS_ERR(req->fmr)) {
 		ret = PTR_ERR(req->fmr);
+		req->fmr = NULL;
 		goto out;
 	}