nvme: opencode revalidate_disk in nvme_validate_ns

Keep control in the NVMe driver instead of going through an indirect
call back into ->revalidate_disk.  Also reorder the function a bit to be
easier to follow with the additional code.

And now that we have removed all callers of revalidate_disk() in the nvme
code, ->revalidate_disk is only called from the open code when first
opening the device.  Which is of course totally pointless as we have
a valid size since the initial scan, and will get an updated view
through the asynchronous notifiation everytime the size changes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/nvme/host/core.c

@@ -2352,7 +2352,6 @@ static const struct block_device_operations nvme_fops = {
 	.open		= nvme_open,
 	.release	= nvme_release,
 	.getgeo		= nvme_getgeo,
-	.revalidate_disk= nvme_revalidate_disk,
 	.report_zones	= nvme_report_zones,
 	.pr_ops		= &nvme_pr_ops,
 };
@@ -4053,14 +4052,19 @@ static void nvme_ns_remove_by_nsid(struct nvme_ctrl *ctrl, u32 nsid)
 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
 {
 	struct nvme_ns *ns;
+	int ret;
 
 	ns = nvme_find_get_ns(ctrl, nsid);
-	if (ns) {
-		if (revalidate_disk(ns->disk))
+	if (!ns) {
+		nvme_alloc_ns(ctrl, nsid);
+		return;
+	}
+
+	ret = nvme_revalidate_disk(ns->disk);
+	revalidate_disk_size(ns->disk, ret == 0);
+	if (ret)
 		nvme_ns_remove(ns);
 	nvme_put_ns(ns);
-	} else
-		nvme_alloc_ns(ctrl, nsid);
 }
 
 static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,