md/md-bitmap: merge md_bitmap_unplug_async() into md_bitmap_unplug()

Add a parameter 'bool sync' to distinguish them, and
md_bitmap_unplug_async() won't be exported anymore, hence
bitmap_operations only need one op to cover them.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-32-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>

drivers/md/md-bitmap.c

@@ -1026,7 +1026,7 @@ static int md_bitmap_file_test_bit(struct bitmap *bitmap, sector_t block)
 /* this gets called when the md device is ready to unplug its underlying
  * (slave) device queues -- before we let any writes go down, we need to
  * sync the dirty pages of the bitmap file to disk */
-void md_bitmap_unplug(struct bitmap *bitmap)
+static void __bitmap_unplug(struct bitmap *bitmap)
 {
 	unsigned long i;
 	int dirty, need_write;
@@ -1058,7 +1058,6 @@ void md_bitmap_unplug(struct bitmap *bitmap)
 	if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
 		md_bitmap_file_kick(bitmap);
 }
-EXPORT_SYMBOL(md_bitmap_unplug);
 
 struct bitmap_unplug_work {
 	struct work_struct work;
@@ -1071,11 +1070,11 @@ static void md_bitmap_unplug_fn(struct work_struct *work)
 	struct bitmap_unplug_work *unplug_work =
 		container_of(work, struct bitmap_unplug_work, work);
 
-	md_bitmap_unplug(unplug_work->bitmap);
+	__bitmap_unplug(unplug_work->bitmap);
 	complete(unplug_work->done);
 }
 
-void md_bitmap_unplug_async(struct bitmap *bitmap)
+static void bitmap_unplug_async(struct bitmap *bitmap)
 {
 	DECLARE_COMPLETION_ONSTACK(done);
 	struct bitmap_unplug_work unplug_work;
@@ -1087,7 +1086,20 @@ void md_bitmap_unplug_async(struct bitmap *bitmap)
 	queue_work(md_bitmap_wq, &unplug_work.work);
 	wait_for_completion(&done);
 }
-EXPORT_SYMBOL(md_bitmap_unplug_async);
+
+void md_bitmap_unplug(struct mddev *mddev, bool sync)
+{
+	struct bitmap *bitmap = mddev->bitmap;
+
+	if (!bitmap)
+		return;
+
+	if (sync)
+		__bitmap_unplug(bitmap);
+	else
+		bitmap_unplug_async(bitmap);
+}
+EXPORT_SYMBOL_GPL(md_bitmap_unplug);
 
 static void md_bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
 
@@ -2108,9 +2120,9 @@ int md_bitmap_copy_from_slot(struct mddev *mddev, int slot,
 		for (i = 0; i < bitmap->storage.file_pages; i++)
 			if (test_page_attr(bitmap, i, BITMAP_PAGE_PENDING))
 				set_page_attr(bitmap, i, BITMAP_PAGE_NEEDWRITE);
-		md_bitmap_unplug(bitmap);
+		__bitmap_unplug(bitmap);
 	}
-	md_bitmap_unplug(mddev->bitmap);
+	__bitmap_unplug(mddev->bitmap);
 	*low = lo;
 	*high = hi;
 	md_bitmap_free(bitmap);
@@ -2351,7 +2363,7 @@ int md_bitmap_resize(struct bitmap *bitmap, sector_t blocks,
 	spin_unlock_irq(&bitmap->counts.lock);
 
 	if (!init) {
-		md_bitmap_unplug(bitmap);
+		__bitmap_unplug(bitmap);
 		bitmap->mddev->pers->quiesce(bitmap->mddev, 0);
 	}
 	ret = 0;

drivers/md/md-bitmap.h

@@ -277,8 +277,7 @@ struct bitmap_operations {
 void mddev_set_bitmap_ops(struct mddev *mddev);
 
 /* these are exported */
-void md_bitmap_unplug(struct bitmap *bitmap);
-void md_bitmap_unplug_async(struct bitmap *bitmap);
+void md_bitmap_unplug(struct mddev *mddev, bool sync);
 void md_bitmap_daemon_work(struct mddev *mddev);
 
 int md_bitmap_resize(struct bitmap *bitmap, sector_t blocks,

drivers/md/md.c

@@ -4715,7 +4715,7 @@ bitmap_store(struct mddev *mddev, const char *buf, size_t len)
 		mddev->bitmap_ops->dirty_bits(mddev, chunk, end_chunk);
 		buf = skip_spaces(end);
 	}
-	md_bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
+	md_bitmap_unplug(mddev, true); /* flush the bits to disk */
 out:
 	mddev_unlock(mddev);
 	return len;

drivers/md/raid1-10.c

@@ -166,12 +166,9 @@ static inline bool raid1_add_bio_to_plug(struct mddev *mddev, struct bio *bio,
  * while current io submission must wait for bitmap io to be done. In order to
  * avoid such deadlock, submit bitmap io asynchronously.
  */
-static inline void raid1_prepare_flush_writes(struct bitmap *bitmap)
+static inline void raid1_prepare_flush_writes(struct mddev *mddev)
 {
-	if (current->bio_list)
-		md_bitmap_unplug_async(bitmap);
-	else
-		md_bitmap_unplug(bitmap);
+	md_bitmap_unplug(mddev, current->bio_list == NULL);
 }
 
 /*

drivers/md/raid1.c

@@ -896,7 +896,7 @@ static void wake_up_barrier(struct r1conf *conf)
 static void flush_bio_list(struct r1conf *conf, struct bio *bio)
 {
 	/* flush any pending bitmap writes to disk before proceeding w/ I/O */
-	raid1_prepare_flush_writes(conf->mddev->bitmap);
+	raid1_prepare_flush_writes(conf->mddev);
 	wake_up_barrier(conf);
 
 	while (bio) { /* submit pending writes */

drivers/md/raid10.c

@@ -885,7 +885,7 @@ static void flush_pending_writes(struct r10conf *conf)
 		__set_current_state(TASK_RUNNING);
 
 		blk_start_plug(&plug);
-		raid1_prepare_flush_writes(conf->mddev->bitmap);
+		raid1_prepare_flush_writes(conf->mddev);
 		wake_up(&conf->wait_barrier);
 
 		while (bio) { /* submit pending writes */
@@ -1101,7 +1101,7 @@ static void raid10_unplug(struct blk_plug_cb *cb, bool from_schedule)
 
 	/* we aren't scheduling, so we can do the write-out directly. */
 	bio = bio_list_get(&plug->pending);
-	raid1_prepare_flush_writes(mddev->bitmap);
+	raid1_prepare_flush_writes(mddev);
 	wake_up_barrier(conf);
 
 	while (bio) { /* submit pending writes */

drivers/md/raid5.c

@@ -6768,7 +6768,7 @@ static void raid5d(struct md_thread *thread)
 			/* Now is a good time to flush some bitmap updates */
 			conf->seq_flush++;
 			spin_unlock_irq(&conf->device_lock);
-			md_bitmap_unplug(mddev->bitmap);
+			md_bitmap_unplug(mddev, true);
 			spin_lock_irq(&conf->device_lock);
 			conf->seq_write = conf->seq_flush;
 			activate_bit_delay(conf, conf->temp_inactive_list);