block: introduce disk_report_zone()

Commit b76b840fd933 ("dm: Fix dm-zoned-reclaim zone write pointer
alignment") introduced an indirect call for the callback function of a
report zones executed with blkdev_report_zones(). This is necessary so
that the function disk_zone_wplug_sync_wp_offset() can be called to
refresh a zone write plug zone write pointer offset after a write error.
However, this solution makes following the path of a zone information
harder to understand.

Clean this up by introducing the new blk_report_zones_args structure to
define a zone report callback and its private data and introduce the
helper function disk_report_zone() which calls both
disk_zone_wplug_sync_wp_offset() and the zone report user callback
function for all zones of a zone report. This helper function must be
called by all block device drivers that implement the report zones
block operation in order to correctly report a zone information.

All block device drivers supporting the report_zones block operation are
updated to use this new scheme.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 30 insertions, 24 deletions

diff --git a/drivers/md/dm-zone.c b/drivers/md/dm-zone.c
index 78e17dd4d01b..984fb621b0e9 100644
--- a/drivers/md/dm-zone.c
+++ b/drivers/md/dm-zone.c
@@ -17,33 +17,26 @@
  * For internal zone reports bypassing the top BIO submission path.
  */
 static int dm_blk_do_report_zones(struct mapped_device *md, struct dm_table *t,
-				  sector_t sector, unsigned int nr_zones,
-				  report_zones_cb cb, void *data)
+				  unsigned int nr_zones,
+				  struct dm_report_zones_args *args)
 {
-	struct gendisk *disk = md->disk;
-	int ret;
-	struct dm_report_zones_args args = {
-		.next_sector = sector,
-		.orig_data = data,
-		.orig_cb = cb,
-	};
-
 	do {
 		struct dm_target *tgt;
+		int ret;
 
-		tgt = dm_table_find_target(t, args.next_sector);
+		tgt = dm_table_find_target(t, args->next_sector);
 		if (WARN_ON_ONCE(!tgt->type->report_zones))
 			return -EIO;
 
-		args.tgt = tgt;
-		ret = tgt->type->report_zones(tgt, &args,
-					      nr_zones - args.zone_idx);
+		args->tgt = tgt;
+		ret = tgt->type->report_zones(tgt, args,
+					      nr_zones - args->zone_idx);
 		if (ret < 0)
 			return ret;
-	} while (args.zone_idx < nr_zones &&
-		 args.next_sector < get_capacity(disk));
+	} while (args->zone_idx < nr_zones &&
+		 args->next_sector < get_capacity(md->disk));
 
-	return args.zone_idx;
+	return args->zone_idx;
 }
 
 /*
@@ -52,7 +45,8 @@ static int dm_blk_do_report_zones(struct mapped_device *md, struct dm_table *t,
  * generally implemented by targets using dm_report_zones().
  */
 int dm_blk_report_zones(struct gendisk *disk, sector_t sector,
-			unsigned int nr_zones, report_zones_cb cb, void *data)
+			unsigned int nr_zones,
+			struct blk_report_zones_args *args)
 {
 	struct mapped_device *md = disk->private_data;
 	struct dm_table *map;
@@ -76,9 +70,14 @@ int dm_blk_report_zones(struct gendisk *disk, sector_t sector,
 		map = zone_revalidate_map;
 	}
 
-	if (map)
-		ret = dm_blk_do_report_zones(md, map, sector, nr_zones, cb,
-					     data);
+	if (map) {
+		struct dm_report_zones_args dm_args = {
+			.disk = md->disk,
+			.next_sector = sector,
+			.rep_args = args,
+		};
+		ret = dm_blk_do_report_zones(md, map, nr_zones, &dm_args);
+	}
 
 	if (put_table)
 		dm_put_live_table(md, srcu_idx);
@@ -113,7 +112,9 @@ static int dm_report_zones_cb(struct blk_zone *zone, unsigned int idx,
 	}
 
 	args->next_sector = zone->start + zone->len;
-	return args->orig_cb(zone, args->zone_idx++, args->orig_data);
+
+	return disk_report_zone(args->disk, zone, args->zone_idx++,
+				args->rep_args);
 }
 
 /*
@@ -492,10 +493,15 @@ int dm_zone_get_reset_bitmap(struct mapped_device *md, struct dm_table *t,
 			     sector_t sector, unsigned int nr_zones,
 			     unsigned long *need_reset)
 {
+	struct dm_report_zones_args args = {
+		.disk = md->disk,
+		.next_sector = sector,
+		.cb = dm_zone_need_reset_cb,
+		.data = need_reset,
+	};
 	int ret;
 
-	ret = dm_blk_do_report_zones(md, t, sector, nr_zones,
-				     dm_zone_need_reset_cb, need_reset);
+	ret = dm_blk_do_report_zones(md, t, nr_zones, &args);
 	if (ret != nr_zones) {
 		DMERR("Get %s zone reset bitmap failed\n",
 		      md->disk->disk_name);