1 /* 2 * fs/sdcardfs/multiuser.h 3 * 4 * Copyright (c) 2013 Samsung Electronics Co. Ltd 5 * Authors: Daeho Jeong, Woojoong Lee, Seunghwan Hyun, 6 * Sunghwan Yun, Sungjong Seo 7 * 8 * This program has been developed as a stackable file system based on 9 * the WrapFS which written by 10 * 11 * Copyright (c) 1998-2011 Erez Zadok 12 * Copyright (c) 2009 Shrikar Archak 13 * Copyright (c) 2003-2011 Stony Brook University 14 * Copyright (c) 2003-2011 The Research Foundation of SUNY 15 * 16 * This file is dual licensed. It may be redistributed and/or modified 17 * under the terms of the Apache 2.0 License OR version 2 of the GNU 18 * General Public License. 19 */ 20 21 #define AID_USER_OFFSET 100000 /* offset for uid ranges for each user */ 22 #define AID_APP_START 10000 /* first app user */ 23 #define AID_APP_END 19999 /* last app user */ 24 #define AID_CACHE_GID_START 20000 /* start of gids for apps to mark cached data */ 25 #define AID_EXT_GID_START 30000 /* start of gids for apps to mark external data */ 26 #define AID_EXT_CACHE_GID_START 40000 /* start of gids for apps to mark external cached data */ 27 #define AID_EXT_CACHE_GID_END 49999 /* end of gids for apps to mark external cached data */ 28 #define AID_SHARED_GID_START 50000 /* start of gids for apps in each user to share */ 29 30 typedef uid_t userid_t; 31 typedef uid_t appid_t; 32 multiuser_get_uid(userid_t user_id,appid_t app_id)33static inline uid_t multiuser_get_uid(userid_t user_id, appid_t app_id) 34 { 35 return (user_id * AID_USER_OFFSET) + (app_id % AID_USER_OFFSET); 36 } 37 uid_is_app(uid_t uid)38static inline bool uid_is_app(uid_t uid) 39 { 40 appid_t appid = uid % AID_USER_OFFSET; 41 42 return appid >= AID_APP_START && appid <= AID_APP_END; 43 } 44 multiuser_get_ext_cache_gid(uid_t uid)45static inline gid_t multiuser_get_ext_cache_gid(uid_t uid) 46 { 47 return uid - AID_APP_START + AID_EXT_CACHE_GID_START; 48 } 49 multiuser_get_ext_gid(uid_t uid)50static inline gid_t multiuser_get_ext_gid(uid_t uid) 51 { 52 return uid - AID_APP_START + AID_EXT_GID_START; 53 } 54