f2fs: introduce f2fs_i_blocks_write with mark_inode_dirty_sync

This patch introduces f2fs_i_blocks_write() to call mark_inode_dirty_sync() when
changing inode->i_blocks.

Signed-off-by: Jaegeuk Kim <[e-mail]>

fs/f2fs/data.c

···
 	if (set_page_dirty(dn->node_page))
 		dn->node_changed = true;
 
-	mark_inode_dirty(dn->inode);
 	sync_inode_page(dn);
 	return 0;
 }

fs/f2fs/f2fs.h

···
 	return ofs == XATTR_NODE_OFFSET;
 }
 
+static inline void f2fs_i_blocks_write(struct inode *, blkcnt_t, bool);
 static inline bool inc_valid_block_count(struct f2fs_sb_info *sbi,
 				 struct inode *inode, blkcnt_t *count)
 {
···
 		}
 	}
 	/* *count can be recalculated */
-	inode->i_blocks += *count;
+	f2fs_i_blocks_write(inode, *count, true);
 	sbi->total_valid_block_count =
 		sbi->total_valid_block_count + (block_t)(*count);
 	spin_unlock(&sbi->stat_lock);
···
 	spin_lock(&sbi->stat_lock);
 	f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
 	f2fs_bug_on(sbi, inode->i_blocks < count);
-	inode->i_blocks -= count;
+	f2fs_i_blocks_write(inode, count, false);
 	sbi->total_valid_block_count -= (block_t)count;
 	spin_unlock(&sbi->stat_lock);
 }
···
 	}
 
 	if (inode)
-		inode->i_blocks++;
+		f2fs_i_blocks_write(inode, 1, true);
 
 	sbi->total_valid_node_count++;
 	sbi->total_valid_block_count++;
···
 	f2fs_bug_on(sbi, !sbi->total_valid_node_count);
 	f2fs_bug_on(sbi, !inode->i_blocks);
 
-	inode->i_blocks--;
+	f2fs_i_blocks_write(inode, 1, false);
 	sbi->total_valid_node_count--;
 	sbi->total_valid_block_count--;
 
···
 {
 	F2FS_I(inode)->i_acl_mode = mode;
 	set_inode_flag(inode, FI_ACL_MODE);
+}
+
+static inline void f2fs_i_blocks_write(struct inode *inode,
+					blkcnt_t diff, bool add)
+{
+	inode->i_blocks = add ? inode->i_blocks + diff :
+				inode->i_blocks - diff;
+	mark_inode_dirty_sync(inode);
 }
 
 static inline void f2fs_i_size_write(struct inode *inode, loff_t i_size)