[PATCH AUTOSEL 4.19 091/128] nvmet: fix data units read and written counters in SMART log

[PATCH AUTOSEL 4.19 091/128] nvmet: fix data units read and written counters in SMART log

[Sasha Levin]

From: Tom Wu <tomwu@mellanox.com>

[ Upstream commit 3bec2e3754becebd4c452999adb49bc62c575ea4 ]

In nvme spec 1.3 there is a definition for data write/read counters
from SMART log, (See section 5.14.1.2):
	This value is reported in thousands (i.e., a value of 1
	corresponds to 1000 units of 512 bytes read) and is rounded up.

However, in nvme target where value is reported with actual units,
but not thousands of units as the spec requires.

Signed-off-by: Tom Wu <tomwu@mellanox.com>
Reviewed-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nvme/target/admin-cmd.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 2008fa62a373b..a8eb8784e151f 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -68,9 +68,11 @@ static u16 nvmet_get_smart_log_nsid(struct nvmet_req *req,
 		goto out;
 
 	host_reads = part_stat_read(ns->bdev->bd_part, ios[READ]);
-	data_units_read = part_stat_read(ns->bdev->bd_part, sectors[READ]);
+	data_units_read = DIV_ROUND_UP(part_stat_read(ns->bdev->bd_part,
+		sectors[READ]), 1000);
 	host_writes = part_stat_read(ns->bdev->bd_part, ios[WRITE]);
-	data_units_written = part_stat_read(ns->bdev->bd_part, sectors[WRITE]);
+	data_units_written = DIV_ROUND_UP(part_stat_read(ns->bdev->bd_part,
+		sectors[WRITE]), 1000);
 
 	put_unaligned_le64(host_reads, &slog->host_reads[0]);
 	put_unaligned_le64(data_units_read, &slog->data_units_read[0]);
@@ -98,11 +100,11 @@ static u16 nvmet_get_smart_log_all(struct nvmet_req *req,
 		if (!ns->bdev)
 			continue;
 		host_reads += part_stat_read(ns->bdev->bd_part, ios[READ]);
-		data_units_read +=
-			part_stat_read(ns->bdev->bd_part, sectors[READ]);
+		data_units_read += DIV_ROUND_UP(
+			part_stat_read(ns->bdev->bd_part, sectors[READ]), 1000);
 		host_writes += part_stat_read(ns->bdev->bd_part, ios[WRITE]);
-		data_units_written +=
-			part_stat_read(ns->bdev->bd_part, sectors[WRITE]);
+		data_units_written += DIV_ROUND_UP(
+			part_stat_read(ns->bdev->bd_part, sectors[WRITE]), 1000);
 
 	}
 	rcu_read_unlock();
-- 
2.20.1


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[PATCH AUTOSEL 4.19 092/128] nvme-multipath: fix ana log nsid lookup when nsid is not found

[Sasha Levin]

From: Anton Eidelman <anton@lightbitslabs.com>

[ Upstream commit e01f91dff91c7b16a6e3faf2565017d497a73f83 ]

ANA log parsing invokes nvme_update_ana_state() per ANA group desc.
This updates the state of namespaces with nsids in desc->nsids[].

Both ctrl->namespaces list and desc->nsids[] array are sorted by nsid.
Hence nvme_update_ana_state() performs a single walk over ctrl->namespaces:
- if current namespace matches the current desc->nsids[n],
  this namespace is updated, and n is incremented.
- the process stops when it encounters the end of either
  ctrl->namespaces end or desc->nsids[]

In case desc->nsids[n] does not match any of ctrl->namespaces,
the remaining nsids following desc->nsids[n] will not be updated.
Such situation was considered abnormal and generated WARN_ON_ONCE.

However ANA log MAY contain nsids not (yet) found in ctrl->namespaces.
For example, lets consider the following scenario:
- nvme0 exposes namespaces with nsids = [2, 3] to the host
- a new namespace nsid = 1 is added dynamically
- also, a ANA topology change is triggered
- NS_CHANGED aen is generated and triggers scan_work
- before scan_work discovers nsid=1 and creates a namespace, a NOTICE_ANA
  aen was issues and ana_work receives ANA log with nsids=[1, 2, 3]

Result: ana_work fails to update ANA state on existing namespaces [2, 3]

Solution:
Change the way nvme_update_ana_state() namespace list walk
checks the current namespace against desc->nsids[n] as follows:
a) ns->head->ns_id < desc->nsids[n]: keep walking ctrl->namespaces.
b) ns->head->ns_id == desc->nsids[n]: match, update the namespace
c) ns->head->ns_id >= desc->nsids[n]: skip to desc->nsids[n+1]

This enables correct operation in the scenario described above.
This also allows ANA log to contain nsids currently invisible
to the host, i.e. inactive nsids.

Signed-off-by: Anton Eidelman <anton@lightbitslabs.com>
Reviewed-by:   James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nvme/host/multipath.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index f57feb8fdea45..892ef52122329 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -404,14 +404,16 @@ static int nvme_update_ana_state(struct nvme_ctrl *ctrl,
 
 	down_write(&ctrl->namespaces_rwsem);
 	list_for_each_entry(ns, &ctrl->namespaces, list) {
-		if (ns->head->ns_id != le32_to_cpu(desc->nsids[n]))
+		unsigned nsid = le32_to_cpu(desc->nsids[n]);
+
+		if (ns->head->ns_id < nsid)
 			continue;
-		nvme_update_ns_ana_state(desc, ns);
+		if (ns->head->ns_id == nsid)
+			nvme_update_ns_ana_state(desc, ns);
 		if (++n == nr_nsids)
 			break;
 	}
 	up_write(&ctrl->namespaces_rwsem);
-	WARN_ON_ONCE(n < nr_nsids);
 	return 0;
 }
 
-- 
2.20.1


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