f2fs: update cur_valid_map_mir together with cur_valid_map

When cur_valid_map passes the f2fs_test_and_set(,clear)_bit test,
cur_valid_map_mir update is skipped unlikely, so fix it. The fix
now changes the mirror check together with cur_valid_map all the
time.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: Fix unused variable and add unlikely for corner condition.]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/segment.c

@@ -1503,6 +1503,10 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
 	struct seg_entry *se;
 	unsigned int segno, offset;
 	long int new_vblocks;
+	bool exist;
+#ifdef CONFIG_F2FS_CHECK_FS
+	bool mir_exist;
+#endif
 
 	segno = GET_SEGNO(sbi, blkaddr);
 
@@ -1519,17 +1523,23 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
 
 	/* Update valid block bitmap */
 	if (del > 0) {
-		if (f2fs_test_and_set_bit(offset, se->cur_valid_map)) {
+		exist = f2fs_test_and_set_bit(offset, se->cur_valid_map);
 #ifdef CONFIG_F2FS_CHECK_FS
-			if (f2fs_test_and_set_bit(offset,
-						se->cur_valid_map_mir))
-				f2fs_bug_on(sbi, 1);
-			else
-				WARN_ON(1);
-#else
+		mir_exist = f2fs_test_and_set_bit(offset,
+						se->cur_valid_map_mir);
+		if (unlikely(exist != mir_exist)) {
+			f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
+				"when setting bitmap, blk:%u, old bit:%d",
+				blkaddr, exist);
 			f2fs_bug_on(sbi, 1);
+		}
 #endif
+		if (unlikely(exist)) {
+			f2fs_msg(sbi->sb, KERN_ERR,
+				"Bitmap was wrongly set, blk:%u", blkaddr);
+			f2fs_bug_on(sbi, 1);
 		}
+
 		if (f2fs_discard_en(sbi) &&
 			!f2fs_test_and_set_bit(offset, se->discard_map))
 			sbi->discard_blks--;
@@ -1540,17 +1550,23 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
 				se->ckpt_valid_blocks++;
 		}
 	} else {
-		if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map)) {
+		exist = f2fs_test_and_clear_bit(offset, se->cur_valid_map);
 #ifdef CONFIG_F2FS_CHECK_FS
-			if (!f2fs_test_and_clear_bit(offset,
-						se->cur_valid_map_mir))
-				f2fs_bug_on(sbi, 1);
-			else
-				WARN_ON(1);
-#else
+		mir_exist = f2fs_test_and_clear_bit(offset,
+						se->cur_valid_map_mir);
+		if (unlikely(exist != mir_exist)) {
+			f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
+				"when clearing bitmap, blk:%u, old bit:%d",
+				blkaddr, exist);
 			f2fs_bug_on(sbi, 1);
+		}
 #endif
+		if (unlikely(!exist)) {
+			f2fs_msg(sbi->sb, KERN_ERR,
+				"Bitmap was wrongly cleared, blk:%u", blkaddr);
+			f2fs_bug_on(sbi, 1);
 		}
+
 		if (f2fs_discard_en(sbi) &&
 			f2fs_test_and_clear_bit(offset, se->discard_map))
 			sbi->discard_blks++;