ocfs2: use ->invalidatepage() length argument

->invalidatepage() aop now accepts range to invalidate so we can make
use of it in ocfs2_invalidatepage().

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Joel Becker <jlbec@evilplan.org>
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 7c47755..79736a2 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -608,8 +608,7 @@
 {
 	journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal;
 
-	jbd2_journal_invalidatepage(journal, page, offset,
-				    PAGE_CACHE_SIZE - offset);
+	jbd2_journal_invalidatepage(journal, page, offset, length);
 }
 
 static int ocfs2_releasepage(struct page *page, gfp_t wait)