gfs2: Truncate address space when flipping GFS2_DIF_JDATA flag

jira LE-2349
Rebuild_History Non-Buildable kernel-4.18.0-553.40.1.el8_10
commit-author Andreas Gruenbacher <agruenba@redhat.com>
commit 7c9d922

Truncate an inode's address space when flipping the GFS2_DIF_JDATA flag:
depending on that flag, the pages in the address space will either use
buffer heads or iomap_folio_state structs, and we cannot mix the two.

	Reported-by: Kun Hu <huk23@m.fudan.edu.cn>, Jiaji Qin <jjtan24@m.fudan.edu.cn>
	Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
(cherry picked from commit 7c9d922)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

fs/gfs2/file.c

@@ -273,6 +273,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask,
 		error = filemap_fdatawait(inode->i_mapping);
 		if (error)
 			goto out;
+		truncate_inode_pages(inode->i_mapping, 0);
 		if (new_flags & GFS2_DIF_JDATA)
 			gfs2_ordered_del_inode(ip);
 	}