54 lines
1.8 KiB
C
54 lines
1.8 KiB
C
/*
|
|
* 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_EXT_CACHE_GID_START 40000 /* start of gids for apps to mark external cached data */
|
|
#define AID_EXT_CACHE_GID_END 49999 /* end of gids for apps to mark external cached 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 bool uid_is_app(uid_t uid)
|
|
{
|
|
appid_t appid = uid % AID_USER_OFFSET;
|
|
|
|
return appid >= AID_APP_START && appid <= AID_APP_END;
|
|
}
|
|
|
|
static inline gid_t multiuser_get_ext_cache_gid(uid_t uid)
|
|
{
|
|
return uid - AID_APP_START + AID_EXT_CACHE_GID_START;
|
|
}
|
|
|
|
static inline gid_t multiuser_get_ext_gid(uid_t uid)
|
|
{
|
|
return uid - AID_APP_START + AID_EXT_GID_START;
|
|
}
|