[PATCH v4 06/13] block: introduce disk_for_all_zone_wplugs()

Introduce the helper function disk_for_all_zone_wplugs() to allow
executing an actor function on all hashed zone write plugs. This helper
is used to simplify the implementation of blk_zone_reset_all_bio_endio()
and queue_zone_wplugs_show().

Signed-off-by: Damien Le Moal <[email protected]>
Reviewed-by: Bart Van Assche <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
---
 block/blk-zoned.c | 68 +++++++++++++++++++++++++----------------------
 1 file changed, 36 insertions(+), 32 deletions(-)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index e3c28db5690c..83737c9a92d8 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -662,6 +662,26 @@ static inline struct blk_zone_wplug *disk_get_zone_wplug(struct gendisk *disk,
 	return disk_get_hashed_zone_wplug(disk, sector);
 }
 
+static void disk_for_all_zone_wplugs(struct gendisk *disk,
+				     void (*actor)(struct blk_zone_wplug *,
+						   void *),
+				     void *data)
+{
+	struct blk_zone_wplug *zwplug;
+	unsigned int i;
+
+	if (!disk->zone_wplugs_hash)
+		return;
+
+	rcu_read_lock();
+	for (i = 0; i < disk_zone_wplugs_hash_size(disk); i++) {
+		hlist_for_each_entry_rcu(zwplug, &disk->zone_wplugs_hash[i],
+					 node)
+			actor(zwplug, data);
+	}
+	rcu_read_unlock();
+}
+
 static void disk_free_zone_wplug_rcu(struct rcu_head *rcu_head)
 {
 	struct blk_zone_wplug *zwplug =
@@ -1200,32 +1220,26 @@ static void blk_zone_reset_bio_endio(struct bio *bio)
 	}
 }
 
+static void disk_zone_wplug_reset_wp(struct blk_zone_wplug *zwplug, void *data)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&zwplug->lock, flags);
+	disk_zone_wplug_set_wp_offset(zwplug->disk, zwplug, 0);
+	spin_unlock_irqrestore(&zwplug->lock, flags);
+}
+
 static void blk_zone_reset_all_bio_endio(struct bio *bio)
 {
 	struct gendisk *disk = bio->bi_bdev->bd_disk;
-	sector_t capacity = get_capacity(disk);
-	struct blk_zone_wplug *zwplug;
-	unsigned long flags;
 	sector_t sector;
-	unsigned int i;
 
-	if (atomic_read(&disk->nr_zone_wplugs)) {
-		/* Update the condition of all zone write plugs. */
-		rcu_read_lock();
-		for (i = 0; i < disk_zone_wplugs_hash_size(disk); i++) {
-			hlist_for_each_entry_rcu(zwplug,
-						 &disk->zone_wplugs_hash[i],
-						 node) {
-				spin_lock_irqsave(&zwplug->lock, flags);
-				disk_zone_wplug_set_wp_offset(disk, zwplug, 0);
-				spin_unlock_irqrestore(&zwplug->lock, flags);
-			}
-		}
-		rcu_read_unlock();
-	}
+	/* Update the condition of all zone write plugs. */
+	if (atomic_read(&disk->nr_zone_wplugs))
+		disk_for_all_zone_wplugs(disk, disk_zone_wplug_reset_wp, NULL);
 
 	/* Update the cached zone conditions. */
-	for (sector = 0; sector < capacity;
+	for (sector = 0; sector < get_capacity(disk);
 	     sector += bdev_zone_sectors(bio->bi_bdev))
 		disk_zone_set_cond(disk, sector, BLK_ZONE_COND_EMPTY);
 	clear_bit(GD_ZONE_APPEND_USED, &disk->state);
@@ -2514,8 +2528,9 @@ EXPORT_SYMBOL_GPL(blk_zone_issue_zeroout);
 
 #ifdef CONFIG_BLK_DEBUG_FS
 static void queue_zone_wplug_show(struct blk_zone_wplug *zwplug,
-				  struct seq_file *m)
+				  void *data)
 {
+	struct seq_file *m = data;
 	unsigned int zwp_wp_offset, zwp_flags;
 	unsigned int zwp_zone_no, zwp_ref;
 	unsigned int zwp_bio_list_size;
@@ -2540,19 +2555,8 @@ static void queue_zone_wplug_show(struct blk_zone_wplug *zwplug,
 int queue_zone_wplugs_show(void *data, struct seq_file *m)
 {
 	struct request_queue *q = data;
-	struct gendisk *disk = q->disk;
-	struct blk_zone_wplug *zwplug;
-	unsigned int i;
-
-	if (!disk->zone_wplugs_hash)
-		return 0;
 
-	rcu_read_lock();
-	for (i = 0; i < disk_zone_wplugs_hash_size(disk); i++)
-		hlist_for_each_entry_rcu(zwplug, &disk->zone_wplugs_hash[i],
-					 node)
-			queue_zone_wplug_show(zwplug, m);
-	rcu_read_unlock();
+	disk_for_all_zone_wplugs(q->disk, queue_zone_wplug_show, m);
 
 	return 0;
 }
-- 
2.55.0