f2fs: fix fsck inconsistency caused by FGGC of node block

During FGGC node block migration, fsck may incorrectly treat the
migrated node block as fsync-written data.

The reproduction scenario:
root@vm:/mnt/f2fs# seq 1 2048 | xargs -n 1 ./test_sync // write inline inode and sync
root@vm:/mnt/f2fs# rm -f 1
root@vm:/mnt/f2fs# sync
root@vm:/mnt/f2fs# f2fs_io gc_range // move data block in sync mode and not write CP
  SPO, "fsck --dry-run" find inode has already checkpointed but still
  with DENT_BIT_SHIFT set

The root cause is that GC does not clear the dentry mark and fsync mark
during node block migration, leading fsck to misinterpret them as
user-issued fsync writes.

In BGGC mode, node block migration is handled by f2fs_sync_node_pages(),
which guarantees the dentry and fsync marks are cleared before writing.

This patch move the set/clear of the fsync|dentry marks into
__write_node_folio to make the logic clearer, and ensures the
fsync|dentry mark is cleared in FGGC.

Cc: stable@kernel.org
Fixes: da011cc ("f2fs: move node pages only in victim section during GC")
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: Yongpeng Yang

fs/f2fs/node.c

@@ -1727,9 +1727,10 @@ static struct folio *last_fsync_dnode(struct f2fs_sb_info *sbi, nid_t ino)
 	return last_folio;
 }
 
-static bool __write_node_folio(struct folio *folio, bool atomic, bool *submitted,
-				struct writeback_control *wbc, bool do_balance,
-				enum iostat_type io_type, unsigned int *seq_id)
+static bool __write_node_folio(struct folio *folio, bool atomic, bool do_fsync,
+				bool *submitted, struct writeback_control *wbc,
+				bool do_balance, enum iostat_type io_type,
+				unsigned int *seq_id)
 {
 	struct f2fs_sb_info *sbi = F2FS_F_SB(folio);
 	nid_t nid;
@@ -1802,6 +1803,8 @@ static bool __write_node_folio(struct folio *folio, bool atomic, bool *submitted
 	if (atomic && !test_opt(sbi, NOBARRIER))
 		fio.op_flags |= REQ_PREFLUSH | REQ_FUA;
 
+	set_dentry_mark(folio, false);
+	set_fsync_mark(folio, do_fsync);
 	if (IS_INODE(folio) && (atomic || is_fsync_dnode(folio)))
 		set_dentry_mark(folio,
 				f2fs_need_dentry_mark(sbi, ino_of_node(folio)));
@@ -1868,7 +1871,7 @@ static int f2fs_write_single_node_folio(struct folio *node_folio, int sync_mode,
 		goto out_folio;
 	}
 
-	if (!__write_node_folio(node_folio, false, NULL,
+	if (!__write_node_folio(node_folio, false, false, NULL,
 				&wbc, false, FS_GC_NODE_IO, NULL))
 		err = -EAGAIN;
 	goto release_folio;
@@ -1915,6 +1918,7 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 		for (i = 0; i < nr_folios; i++) {
 			struct folio *folio = fbatch.folios[i];
 			bool submitted = false;
+			bool do_fsync = false;
 
 			if (unlikely(f2fs_cp_error(sbi))) {
 				f2fs_folio_put(last_folio, false);
@@ -1945,11 +1949,8 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 
 			f2fs_folio_wait_writeback(folio, NODE, true, true);
 
-			set_fsync_mark(folio, 0);
-			set_dentry_mark(folio, 0);
-
 			if (!atomic || folio == last_folio) {
-				set_fsync_mark(folio, 1);
+				do_fsync = true;
 				percpu_counter_inc(&sbi->rf_node_block_count);
 				if (IS_INODE(folio)) {
 					if (is_inode_flag_set(inode,
@@ -1966,8 +1967,9 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 
 			if (!__write_node_folio(folio, atomic &&
 						folio == last_folio,
-						&submitted, wbc, true,
-						FS_NODE_IO, seq_id)) {
+						do_fsync, &submitted,
+						wbc, true, FS_NODE_IO,
+						seq_id)) {
 				f2fs_folio_put(last_folio, false);
 				folio_batch_release(&fbatch);
 				ret = -EIO;
@@ -2167,10 +2169,7 @@ int f2fs_sync_node_pages(struct f2fs_sb_info *sbi,
 			if (!folio_clear_dirty_for_io(folio))
 				goto continue_unlock;
 
-			set_fsync_mark(folio, 0);
-			set_dentry_mark(folio, 0);
-
-			if (!__write_node_folio(folio, false, &submitted,
+			if (!__write_node_folio(folio, false, false, &submitted,
 					wbc, do_balance, io_type, NULL)) {
 				folio_batch_release(&fbatch);
 				ret = -EIO;