iomap: Fix misplaced page flushing

If iomap_unshare_actor() unshares to an inline iomap, the page was
not being flushed.  block_write_end() and __iomap_write_end() already
contain flushes, so adding it to iomap_write_end_inline() seems like
the best place.  That means we can remove it from iomap_write_actor().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/iomap/buffered-io.c

@@ -717,6 +717,7 @@ iomap_write_end_inline(struct inode *inode, struct page *page,
 	WARN_ON_ONCE(!PageUptodate(page));
 	BUG_ON(pos + copied > PAGE_SIZE - offset_in_page(iomap->inline_data));
 
+	flush_dcache_page(page);
 	addr = kmap_atomic(page);
 	memcpy(iomap->inline_data + pos, addr + pos, copied);
 	kunmap_atomic(addr);
@@ -810,8 +811,6 @@ iomap_write_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
 
 		copied = iov_iter_copy_from_user_atomic(page, i, offset, bytes);
 
-		flush_dcache_page(page);
-
 		status = iomap_write_end(inode, pos, bytes, copied, page, iomap,
 				srcmap);
 		if (unlikely(status < 0))