f2fs: invalidate xattr node page when evict inode

When inode is evicted, all the page cache belong to this inode should be
released including the xattr node page. But previously we didn't do this, this
patch fixed this issue.

v2:
 o reposition invalidate_mapping_pages() to the right place suggested by
Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/inode.c

@@ -267,6 +267,7 @@ int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc)
 void f2fs_evict_inode(struct inode *inode)
 {
 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 
 	trace_f2fs_evict_inode(inode);
 	truncate_inode_pages_final(&inode->i_data);
@@ -296,6 +297,8 @@ void f2fs_evict_inode(struct inode *inode)
 	sb_end_intwrite(inode->i_sb);
 no_delete:
 	invalidate_mapping_pages(NODE_MAPPING(sbi), inode->i_ino, inode->i_ino);
+	if (xnid)
+		invalidate_mapping_pages(NODE_MAPPING(sbi), xnid, xnid);
 	if (is_inode_flag_set(F2FS_I(inode), FI_APPEND_WRITE))
 		add_dirty_inode(sbi, inode->i_ino, APPEND_INO);
 	if (is_inode_flag_set(F2FS_I(inode), FI_UPDATE_WRITE))