[PATCH 3/3] dm: fix zone reset all operation processing

[Damien Le Moal <dlemoal@kernel.org>]

dm_zone_get_reset_bitmap() is used to generate a bitmap of the zones of
a zoned device target when a REQ_OP_ZONE_RESET_ALL request is being
processed. This bitmap is built by executing a zone report with a report
callback set to the function dm_zone_need_reset_cb() in struct
dm_report_zones_args. However, the cb callback pointer is not anymore
the same as the callback specified by callers of the
blkdev_report_zones() function. Rather, this is a DM internal callback
and report zones callback functions from blkdev_report_zones() are
passed using struct blk_report_zones_args, introduced with commit
db9aed869f34 ("block: introduce disk_report_zone()").

This commit changed the DM main report zones callback handler function
dm_report_zones_cb() to call the new disk_report_zone() so that callback
functions from blkdev_report_zones() are executed, and this change
resulted in the DM internal dm_zone_need_reset_cb() callback function to
not be executed anymore, turning any REQ_OP_ZONE_RESET_ALL request into
a no-op.

Fix this by calling in dm_report_zones_cb() the DM internal cb function
specified in struct dm_report_zones_args.

Fixes: db9aed869f34 ("block: introduce disk_report_zone()").
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/md/dm-zone.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/md/dm-zone.c b/drivers/md/dm-zone.c
index 984fb621b0e9..5a840c4ae316 100644
--- a/drivers/md/dm-zone.c
+++ b/drivers/md/dm-zone.c
@@ -113,6 +113,15 @@ static int dm_report_zones_cb(struct blk_zone *zone, unsigned int idx,
 
 	args->next_sector = zone->start + zone->len;
 
+	/* If we have an internal callback, call it first. */
+	if (args->cb) {
+		int ret;
+
+		ret = args->cb(zone, args->zone_idx, args->data);
+		if (ret)
+			return ret;
+	}
+
 	return disk_report_zone(args->disk, zone, args->zone_idx++,
 				args->rep_args);
 }
-- 
2.51.1