IB/qib: Fix an error code in qib_sdma_verbs_send()

mainline inclusion
from mainline-5.0-rc1
commit 5050ae5fa3d54c8e83e1e447cc7e3591110a7f57
category: bugfix
bugzilla: 6535
CVE: NA

----------------------

We accidentally return success on this error path.

Fixes: f931551b ("IB/qib: Add new qib driver for QLogic PCIe InfiniBand adapters")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NJing xiangfeng <jingxiangfeng@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/infiniband/hw/qib/qib_sdma.c

@@ -576,8 +576,10 @@ int qib_sdma_verbs_send(struct qib_pportdata *ppd,
 		dw = (len + 3) >> 2;
 		addr = dma_map_single(&ppd->dd->pcidev->dev, sge->vaddr,
 				      dw << 2, DMA_TO_DEVICE);
-		if (dma_mapping_error(&ppd->dd->pcidev->dev, addr))
+		if (dma_mapping_error(&ppd->dd->pcidev->dev, addr)) {
+			ret = -ENOMEM;
 			goto unmap;
+		}
 		sdmadesc[0] = 0;
 		make_sdma_desc(ppd, sdmadesc, (u64) addr, dw, dwoffset);
 		/* SDmaUseLargeBuf has to be set in every descriptor */