[PATCH 03/10] nvme: Only update capacity for optimized or non-optimized paths

[hare@suse.de (Hannes Reinecke)]

As per ANA spec paths in 'inaccessible' or 'persistent-loss' state
might return a capacity of '0'. So when an inaccessible path is
detected last it might overwrite the actual capacity with '0',
rendering the device unuseable.
Hence we should only be updating the capacity if we are sure that
we've read the correct one.

Signed-off-by: Hannes Reinecke <hare at suse.com>
---
 drivers/nvme/host/core.c      |  4 +++-
 drivers/nvme/host/multipath.c |  9 ---------
 drivers/nvme/host/nvme.h      | 13 +++++++++++++
 3 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 1be424053f47..cc43bb685e63 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1457,7 +1457,9 @@ static void nvme_update_disk_info(struct gendisk *disk,
 	if (ns->ms && !nvme_ns_has_pi(ns) && !blk_get_integrity(disk))
 		capacity = 0;
 
-	set_capacity(disk, capacity);
+	if (nvme_ns_ana_state(ns) == NVME_ANA_OPTIMIZED ||
+	    nvme_ns_ana_state(ns) == NVME_ANA_NONOPTIMIZED)
+		set_capacity(disk, capacity);
 	nvme_config_discard(ns);
 	blk_mq_unfreeze_queue(disk->queue);
 }
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 2fcaf50d84e2..a5f43d164b19 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -108,15 +108,6 @@ void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl)
 	up_read(&ctrl->namespaces_rwsem);
 }
 
-static inline enum nvme_ana_state nvme_ns_ana_state(struct nvme_ns *ns)
-{
-	if (!nvme_ctrl_has_ana(ns->ctrl))
-		return NVME_ANA_OPTIMIZED;
-	if (WARN_ON_ONCE(ns->anagrpid > ns->ctrl->anagrpmax))
-		return 0;
-	return READ_ONCE(ns->ctrl->ana_state[ns->anagrpid]);
-}
-
 static const char *nvme_ana_state_names[] = {
 	[0]				= "invalid state",
 	[NVME_ANA_OPTIMIZED]		= "optimized",
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 53cb7f8a6267..8572f106d6ac 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -485,6 +485,15 @@ static inline void nvme_mpath_check_last_path(struct nvme_ns *ns)
 		kblockd_schedule_work(&head->requeue_work);
 }
 
+static inline enum nvme_ana_state nvme_ns_ana_state(struct nvme_ns *ns)
+{
+	if (!nvme_ctrl_has_ana(ns->ctrl))
+		return NVME_ANA_OPTIMIZED;
+	if (WARN_ON_ONCE(ns->anagrpid > ns->ctrl->anagrpmax))
+		return 0;
+	return READ_ONCE(ns->ctrl->ana_state[ns->anagrpid]);
+}
+
 extern struct device_attribute dev_attr_ana_grpid;
 extern struct device_attribute dev_attr_ana_state;
 
@@ -534,6 +543,10 @@ static inline int nvme_configure_ana(struct nvme_ctrl *ctrl)
 static inline void nvme_deconfigure_ana(struct nvme_ctrl *ctrl)
 {
 }
+static inline enum nvme_ana_state nvme_ns_ana_state(struct nvme_ns *ns)
+{
+	return NVME_ANA_OPTIMIZED;
+}
 #endif /* CONFIG_NVME_MULTIPATH */
 
 #ifdef CONFIG_NVM
-- 
2.12.3