ceph: don't leak snap_rwsem in handle_cap_grant

stable inclusion
from stable-v5.10.138
commit aee18421bda6bf12a7cba6a3d7751c0e1cfd0094
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60QFD

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=aee18421bda6bf12a7cba6a3d7751c0e1cfd0094

--------------------------------

commit 58dd4385 upstream.

When handle_cap_grant is called on an IMPORT op, then the snap_rwsem is
held and the function is expected to release it before returning. It
currently fails to do that in all cases which could lead to a deadlock.

Fixes: 6f05b30e ("ceph: reset i_requested_max_size if file write is not wanted")
Link: https://tracker.ceph.com/issues/55857


Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luís Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>