[PATCH 1/5] btrfs: factor out dirty-clearing part of btrfs_clear_buffer_dirty

Split the dirty-clearing part of btrfs_clear_buffer_dirty() into a helper so
a later caller can reuse it while bypassing the zoned zero-out deferral.
No functional change.

Signed-off-by: Johannes Thumshirn <[email protected]>
---
 fs/btrfs/extent_io.c | 47 +++++++++++++++++++++++++-------------------
 1 file changed, 27 insertions(+), 20 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 647b109ef61b..4dd8fc5ad247 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3788,6 +3788,32 @@ void free_extent_buffer_stale(struct extent_buffer *eb)
 	release_extent_buffer(eb);
 }
 
+static void __btrfs_clear_buffer_dirty(struct extent_buffer *eb)
+{
+	struct btrfs_fs_info *fs_info = eb->fs_info;
+
+	if (!test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags))
+		return;
+
+	buffer_tree_clear_mark(eb, PAGECACHE_TAG_DIRTY);
+	percpu_counter_add_batch(&fs_info->dirty_metadata_bytes, -(s64)eb->len,
+				 fs_info->dirty_metadata_batch);
+
+	for (int i = 0; i < num_extent_folios(eb); i++) {
+		struct folio *folio = eb->folios[i];
+		bool last;
+
+		if (!folio_test_dirty(folio))
+			continue;
+		folio_lock(folio);
+		last = btrfs_meta_folio_clear_and_test_dirty(folio, eb);
+		if (last)
+			btrfs_clear_folio_dirty_tag(folio);
+		folio_unlock(folio);
+	}
+	WARN_ON(refcount_read(&eb->refs) == 0);
+}
+
 void btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,
 			      struct extent_buffer *eb)
 {
@@ -3812,26 +3838,7 @@ void btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,
 		return;
 	}
 
-	if (!test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags))
-		return;
-
-	buffer_tree_clear_mark(eb, PAGECACHE_TAG_DIRTY);
-	percpu_counter_add_batch(&fs_info->dirty_metadata_bytes, -(s64)eb->len,
-				 fs_info->dirty_metadata_batch);
-
-	for (int i = 0; i < num_extent_folios(eb); i++) {
-		struct folio *folio = eb->folios[i];
-		bool last;
-
-		if (!folio_test_dirty(folio))
-			continue;
-		folio_lock(folio);
-		last = btrfs_meta_folio_clear_and_test_dirty(folio, eb);
-		if (last)
-			btrfs_clear_folio_dirty_tag(folio);
-		folio_unlock(folio);
-	}
-	WARN_ON(refcount_read(&eb->refs) == 0);
+	__btrfs_clear_buffer_dirty(eb);
 }
 
 void set_extent_buffer_dirty(struct extent_buffer *eb)
-- 
2.54.0