Re: [PATCH 03/24] nvme: let set_capacity_revalidate_and_notify update the bdev size

Christoph Hellwig
2020-11-09T08:53:49Z

On Mon, Nov 09, 2020 at 08:53:58AM +0100, Hannes Reinecke wrote:
>> index 376096bfc54a83..4e86c9aafd88a7 100644
>> --- a/drivers/nvme/host/core.c
>> +++ b/drivers/nvme/host/core.c
>> @@ -2053,7 +2053,7 @@ static void nvme_update_disk_info(struct gendisk *disk,
>> capacity = 0;
>> }
>> - set_capacity_revalidate_and_notify(disk, capacity, false);
>> + set_capacity_revalidate_and_notify(disk, capacity, true);
>> nvme_config_discard(disk, ns);
>> nvme_config_write_zeroes(disk, ns);
>> @@ -2136,7 +2136,6 @@ static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_id_ns *id)
>> blk_stack_limits(&ns->head->disk->queue->limits,
>> &ns->queue->limits, 0);
>> blk_queue_update_readahead(ns->head->disk->queue);
>> - nvme_update_bdev_size(ns->head->disk);
>> blk_mq_unfreeze_queue(ns->head->disk->queue);
>> }
>> #endif
>
> Hold on.
> This, at the very least, should be a separate patch.
> With this you are changing the behaviour of nvme multipath.
>
> Originally nvme multipath would update/change the size of the multipath
> device according to the underlying path devices.
> With this patch the size of the multipath device will _not_ change if there
> is a change on the underlying devices.

Yes, it will. Take a close look at nvme_update_disk_info and how it is
called.