Commit e7d65803 authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Christoph Hellwig
Browse files

nvme-multipath: revalidate paths during rescan 



When triggering a rescan due to a namespace resize we will be
receiving AENs on every controller, triggering a rescan of all
attached namespaces. If multipath is active only the current path and
the ns_head disk will be updated, the other paths will still refer to
the old size until AENs for the remaining controllers are received.

If I/O comes in before that it might be routed to one of the old
paths, triggering an I/O failure with 'access beyond end of device'.
With this patch the old paths are skipped from multipath path
selection until the controller serving these paths has been rescanned.

Signed-off-by: default avatarHannes Reinecke <hare@suse.de>
[dwagner: - introduce NVME_NS_READY flag instead of NVME_NS_INVALIDATE
          - use 'revalidate' instead of 'invalidate' which
	    follows the zoned device code path.
	  - clear NVME_NS_READY before clearing current_path]
Signed-off-by: default avatarDaniel Wagner <dwagner@suse.de>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent d32d3d0b

drivers/nvme/host/core.c

+3 −0
Original line number Diff line number Diff line
@@ -1874,6 +1874,7 @@ static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_id_ns *id) 
			goto out_unfreeze;

	}



	set_bit(NVME_NS_READY, &ns->flags);

	blk_mq_unfreeze_queue(ns->disk->queue);



	if (blk_queue_is_zoned(ns->queue)) {
@@ -1885,6 +1886,7 @@ static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_id_ns *id) 
	if (nvme_ns_head_multipath(ns->head)) {

		blk_mq_freeze_queue(ns->head->disk->queue);

		nvme_update_disk_info(ns->head->disk, ns, id);

		nvme_mpath_revalidate_paths(ns);

		blk_stack_limits(&ns->head->disk->queue->limits,

				 &ns->queue->limits, 0);

		disk_update_readahead(ns->head->disk);
@@ -3795,6 +3797,7 @@ static void nvme_ns_remove(struct nvme_ns *ns) 
	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))

		return;



	clear_bit(NVME_NS_READY, &ns->flags);

	set_capacity(ns->disk, 0);

	nvme_fault_inject_fini(&ns->fault_inject);

drivers/nvme/host/multipath.c

+16 −1
Original line number Diff line number Diff line
@@ -147,6 +147,21 @@ void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl) 
	mutex_unlock(&ctrl->scan_lock);

}



void nvme_mpath_revalidate_paths(struct nvme_ns *ns)

{

	struct nvme_ns_head *head = ns->head;

	sector_t capacity = get_capacity(head->disk);

	int node;



	list_for_each_entry_rcu(ns, &head->list, siblings) {

		if (capacity != get_capacity(ns->disk))

			clear_bit(NVME_NS_READY, &ns->flags);

	}



	for_each_node(node)

		rcu_assign_pointer(head->current_path[node], NULL);

}



static bool nvme_path_is_disabled(struct nvme_ns *ns)

{

	/*
@@ -158,7 +173,7 @@ static bool nvme_path_is_disabled(struct nvme_ns *ns) 
	    ns->ctrl->state != NVME_CTRL_DELETING)

		return true;

	if (test_bit(NVME_NS_ANA_PENDING, &ns->flags) ||

	    test_bit(NVME_NS_REMOVING, &ns->flags))

	    !test_bit(NVME_NS_READY, &ns->flags))

		return true;

	return false;

}

drivers/nvme/host/nvme.h

+5 −0
Original line number Diff line number Diff line
@@ -456,6 +456,7 @@ struct nvme_ns { 
#define NVME_NS_DEAD     	1

#define NVME_NS_ANA_PENDING	2

#define NVME_NS_FORCE_RO	3

#define NVME_NS_READY		4



	struct cdev		cdev;

	struct device		cdev_device;
@@ -748,6 +749,7 @@ void nvme_mpath_init_ctrl(struct nvme_ctrl *ctrl); 
void nvme_mpath_uninit(struct nvme_ctrl *ctrl);

void nvme_mpath_stop(struct nvme_ctrl *ctrl);

bool nvme_mpath_clear_current_path(struct nvme_ns *ns);

void nvme_mpath_revalidate_paths(struct nvme_ns *ns);

void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl);

void nvme_mpath_shutdown_disk(struct nvme_ns_head *head);
@@ -795,6 +797,9 @@ static inline bool nvme_mpath_clear_current_path(struct nvme_ns *ns) 
{

	return false;

}

static inline void nvme_mpath_revalidate_paths(struct nvme_ns *ns)

{

}

static inline void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl)

{

}