nvme: refactor nvme_identify_ns_descs error handling

mainline inclusion
from mainline-v5.7-rc1
commit fb314eb0
category: bugfix
bugzilla: NA
CVE: NA
Link: https://gitee.com/openeuler/kernel/issues/I4JFBE?from=project-issue

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

Move the handling of an error into the function from the caller, and
only do it for an actual error on the admin command itself, not the
command parsing, as that should be enough to deal with devices claiming
a bogus version compliance.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: Nchengjike <chengjike.cheng@huawei.com>
Reviewed-by: NHou Tao <houtao1@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/nvme/host/core.c

@@ -997,8 +997,17 @@ static int nvme_identify_ns_descs(struct nvme_ctrl *ctrl, unsigned nsid,
 
 	status = nvme_submit_sync_cmd(ctrl->admin_q, &c, data,
 				      NVME_IDENTIFY_DATA_SIZE);
-	if (status)
+	if (status) {
+		dev_warn(ctrl->device,
+			"Identify Descriptors failed (%d)\n", status);
+		 /*
+		  * Don't treat an error as fatal, as we potentially already
+		  * have a NGUID or EUI-64.
+		  */
+		if (status > 0)
+			status = 0;
 		goto free_data;
+	}
 
 	for (pos = 0; pos < NVME_IDENTIFY_DATA_SIZE; pos += len) {
 		struct nvme_ns_id_desc *cur = data + pos;
@@ -1592,26 +1601,15 @@ static void nvme_config_discard(struct gendisk *disk, struct nvme_ns *ns)
 static int nvme_report_ns_ids(struct nvme_ctrl *ctrl, unsigned int nsid,
 		struct nvme_id_ns *id, struct nvme_ns_ids *ids)
 {
-	int ret = 0;
-
 	memset(ids, 0, sizeof(*ids));
 
 	if (ctrl->vs >= NVME_VS(1, 1, 0))
 		memcpy(ids->eui64, id->eui64, sizeof(id->eui64));
 	if (ctrl->vs >= NVME_VS(1, 2, 0))
 		memcpy(ids->nguid, id->nguid, sizeof(id->nguid));
-	if (ctrl->vs >= NVME_VS(1, 3, 0)) {
-		 /* Don't treat error as fatal we potentially
-		  * already have a NGUID or EUI-64
-		  */
-		ret = nvme_identify_ns_descs(ctrl, nsid, ids);
-		if (ret)
-			dev_warn(ctrl->device,
-				 "Identify Descriptors failed (%d)\n", ret);
-		if (ret > 0)
-			ret = 0;
-	}
-	return ret;
+	if (ctrl->vs >= NVME_VS(1, 3, 0))
+		return nvme_identify_ns_descs(ctrl, nsid, ids);
+	return 0;
 }
 
 static bool nvme_ns_ids_valid(struct nvme_ns_ids *ids)