commit 75b396821c upstream.
This eliminates a check for shared that was overrestrictive and
prevented read-only mmaps when writeback caches weren't enabled.
Cc: stable@vger.kernel.org
Fixes: 1543b4c507 ("fs/9p: remove writeback fid and fix per-file modes")
Reported-by: Robert Schwebel <r.schwebel@pengutronix.de>
Closes: https://lore.kernel.org/v9fs/ZK25XZ%2BGpR3KHIB%2F@pengutronix.de
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>