[PATCH v2 3/3] null_blk: clean up setting zones read-only or offline

[Niklas Cassel <cassel@kernel.org>]

null_set_zone_cond() takes a zone condition, even though read-only and
offline are the only zone conditions that it can set. Because of this,
it needs a WARN_ON_ONCE() to reject any other zone condition, and its
name suggests a generic helper that can set any zone condition.

Rename null_set_zone_cond() to null_set_zone_readonly_or_offline(), and
replace its zone condition argument with a bool, set_offline, which
selects between the read-only and offline conditions. Also remove the
comment above the function, as it only repeats the new function name.

zone_cond_store() keeps taking a zone condition, as it, unlike
null_set_zone_readonly_or_offline(), contains generic code, and might
be extended to support additional zone conditions in the future.

No functional change, as zone_cond_store() is only called with the
read-only or offline condition.

Suggested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/block/null_blk/zoned.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c
index 015f5d304c7ce..b271d0a88ff21 100644
--- a/drivers/block/null_blk/zoned.c
+++ b/drivers/block/null_blk/zoned.c
@@ -770,15 +770,12 @@ static void null_release_zone_resources(struct nullb_device *dev,
 	spin_unlock(&dev->zone_res_lock);
 }
 
-/*
- * Set a zone in the read-only or offline condition.
- */
-static void null_set_zone_cond(struct nullb_device *dev,
-			       struct nullb_zone *zone, enum blk_zone_cond cond)
+static void null_set_zone_readonly_or_offline(struct nullb_device *dev,
+					      struct nullb_zone *zone,
+					      bool set_offline)
 {
-	if (WARN_ON_ONCE(cond != BLK_ZONE_COND_READONLY &&
-			 cond != BLK_ZONE_COND_OFFLINE))
-		return;
+	enum blk_zone_cond cond =
+		set_offline ? BLK_ZONE_COND_OFFLINE : BLK_ZONE_COND_READONLY;
 
 	null_lock_zone(dev, zone);
 
@@ -814,6 +811,11 @@ ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
 	unsigned int zone_no;
 	int ret;
 
+	/* Read-only and offline are the only conditions supported for now */
+	if (WARN_ON_ONCE(cond != BLK_ZONE_COND_READONLY &&
+			 cond != BLK_ZONE_COND_OFFLINE))
+		return -EINVAL;
+
 	if (!dev->zoned) {
 		pr_err("null_blk device is not zoned\n");
 		return -EINVAL;
@@ -839,7 +841,8 @@ ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
 		return -EINVAL;
 	}
 
-	null_set_zone_cond(dev, &dev->zones[zone_no], cond);
+	null_set_zone_readonly_or_offline(dev, &dev->zones[zone_no],
+					  cond == BLK_ZONE_COND_OFFLINE);
 
 	return count;
 }
-- 
2.56.0