From 3af5ae22030cb59fab4fba35f5a2b62f47e14df9 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Tue, 25 Jul 2023 09:44:40 +0800 Subject: [PATCH] ceph: make members in struct ceph_mds_request_args_ext a union In ceph mainline it will allow to set the btime in the setattr request and just add a 'btime' member in the union 'ceph_mds_request_args' and then bump up the header version to 4. That means the total size of union 'ceph_mds_request_args' will increase sizeof(struct ceph_timespec) bytes, but in kclient it will increase the sizeof(setattr_ext) bytes for each request. Since the MDS will always depend on the header's vesion and front_len members to decode the 'ceph_mds_request_head' struct, at the same time kclient hasn't supported the 'btime' feature yet in setattr request, so it's safe to do this change here. This will save 48 bytes memories for each request. Fixes: 4f1ddb1ea874 ("ceph: implement updated ceph_mds_request_head structure") Signed-off-by: Xiubo Li Reviewed-by: Milind Changire Signed-off-by: Ilya Dryomov --- include/linux/ceph/ceph_fs.h | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h index 45f8ce6..ae44812 100644 --- a/include/linux/ceph/ceph_fs.h +++ b/include/linux/ceph/ceph_fs.h @@ -467,17 +467,19 @@ union ceph_mds_request_args { } __attribute__ ((packed)); union ceph_mds_request_args_ext { - union ceph_mds_request_args old; - struct { - __le32 mode; - __le32 uid; - __le32 gid; - struct ceph_timespec mtime; - struct ceph_timespec atime; - __le64 size, old_size; /* old_size needed by truncate */ - __le32 mask; /* CEPH_SETATTR_* */ - struct ceph_timespec btime; - } __attribute__ ((packed)) setattr_ext; + union { + union ceph_mds_request_args old; + struct { + __le32 mode; + __le32 uid; + __le32 gid; + struct ceph_timespec mtime; + struct ceph_timespec atime; + __le64 size, old_size; /* old_size needed by truncate */ + __le32 mask; /* CEPH_SETATTR_* */ + struct ceph_timespec btime; + } __attribute__ ((packed)) setattr_ext; + }; }; #define CEPH_MDS_FLAG_REPLAY 1 /* this is a replayed op */ -- 2.7.4