blob: 2e89b587231402a459bd86e0623856ead76cf339 [file] [log] [blame]
/*
* fs/sdcardfs/multiuser.h
*
* Copyright (c) 2013 Samsung Electronics Co. Ltd
* Authors: Daeho Jeong, Woojoong Lee, Seunghwan Hyun,
* Sunghwan Yun, Sungjong Seo
*
* This program has been developed as a stackable file system based on
* the WrapFS which written by
*
* Copyright (c) 1998-2011 Erez Zadok
* Copyright (c) 2009 Shrikar Archak
* Copyright (c) 2003-2011 Stony Brook University
* Copyright (c) 2003-2011 The Research Foundation of SUNY
*
* This file is dual licensed. It may be redistributed and/or modified
* under the terms of the Apache 2.0 License OR version 2 of the GNU
* General Public License.
*/
#define AID_USER_OFFSET 100000 /* offset for uid ranges for each user */
#define AID_APP_START 10000 /* first app user */
#define AID_APP_END 19999 /* last app user */
#define AID_CACHE_GID_START 20000 /* start of gids for apps to mark cached data */
#define AID_EXT_GID_START 30000 /* start of gids for apps to mark external data */
#define AID_SHARED_GID_START 50000 /* start of gids for apps in each user to share */
typedef uid_t userid_t;
typedef uid_t appid_t;
static inline uid_t multiuser_get_uid(userid_t user_id, appid_t app_id)
{
return (user_id * AID_USER_OFFSET) + (app_id % AID_USER_OFFSET);
}
static inline gid_t multiuser_get_cache_gid(uid_t uid)
{
return uid - AID_APP_START + AID_CACHE_GID_START;
}
static inline gid_t multiuser_get_ext_gid(uid_t uid)
{
return uid - AID_APP_START + AID_EXT_GID_START;
}