f2fs: retain inconsistency information to initiate fsck.f2fs

This patch adds sbi->need_fsck to conduct fsck.f2fs later.
This flag can only be removed by fsck.f2fs.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/checkpoint.c

@@ -882,6 +882,9 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
 	else
 		clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
 
+	if (sbi->need_fsck)
+		set_ckpt_flags(ckpt, CP_FSCK_FLAG);
+
 	/* update SIT/NAT bitmap */
 	get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
 	get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));

fs/f2fs/f2fs.h

@@ -434,6 +434,7 @@ struct f2fs_sb_info {
 	struct buffer_head *raw_super_buf;	/* buffer head of raw sb */
 	struct f2fs_super_block *raw_super;	/* raw super block pointer */
 	int s_dirty;				/* dirty flag for checkpoint */
+	bool need_fsck;				/* need fsck.f2fs to fix */
 
 	/* for node-related operations */
 	struct f2fs_nm_info *nm_info;		/* node manager */

fs/f2fs/super.c

@@ -849,6 +849,7 @@ static void init_sb_info(struct f2fs_sb_info *sbi)
 		atomic_set(&sbi->nr_pages[i], 0);
 
 	sbi->dir_level = DEF_DIR_LEVEL;
+	sbi->need_fsck = false;
 }
 
 /*

include/linux/f2fs_fs.h

@@ -85,6 +85,7 @@ struct f2fs_super_block {
 /*
  * For checkpoint
  */
+#define CP_FSCK_FLAG		0x00000010
 #define CP_ERROR_FLAG		0x00000008
 #define CP_COMPACT_SUM_FLAG	0x00000004
 #define CP_ORPHAN_PRESENT_FLAG	0x00000002