splice: Make filemap_splice_read() check s_maxbytes

Make filemap_splice_read() check s_maxbytes analogously to filemap_read().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
cc: Steve French <stfrench@microsoft.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: David Hildenbrand <david@redhat.com>
cc: John Hubbard <jhubbard@nvidia.com>
cc: linux-mm@kvack.org
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20230522135018.2742245-3-dhowells@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mm/filemap.c

@@ -2887,6 +2887,9 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
 	bool writably_mapped;
 	int i, error = 0;
 
+	if (unlikely(*ppos >= in->f_mapping->host->i_sb->s_maxbytes))
+		return 0;
+
 	init_sync_kiocb(&iocb, in);
 	iocb.ki_pos = *ppos;