1 /* 2 * V9FS definitions. 3 * 4 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> 5 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 9 * as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to: 18 * Free Software Foundation 19 * 51 Franklin Street, Fifth Floor 20 * Boston, MA 02111-1301 USA 21 * 22 */ 23 #include <linux/backing-dev.h> 24 25 /** 26 * enum p9_session_flags - option flags for each 9P session 27 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions 28 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions 29 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy 30 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default) 31 * @V9FS_ACCESS_ANY: use a single attach for all users 32 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options 33 * 34 * Session flags reflect options selected by users at mount time 35 */ 36 enum p9_session_flags { 37 V9FS_PROTO_2000U = 0x01, 38 V9FS_PROTO_2000L = 0x02, 39 V9FS_ACCESS_SINGLE = 0x04, 40 V9FS_ACCESS_USER = 0x08, 41 V9FS_ACCESS_ANY = 0x0C, 42 V9FS_ACCESS_MASK = 0x0C, 43 }; 44 45 /* possible values of ->cache */ 46 /** 47 * enum p9_cache_modes - user specified cache preferences 48 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 49 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 50 * 51 * eventually support loose, tight, time, session, default always none 52 */ 53 54 enum p9_cache_modes { 55 CACHE_NONE, 56 CACHE_LOOSE, 57 CACHE_FSCACHE, 58 }; 59 60 /** 61 * struct v9fs_session_info - per-instance session information 62 * @flags: session options of type &p9_session_flags 63 * @nodev: set to 1 to disable device mapping 64 * @debug: debug level 65 * @afid: authentication handle 66 * @cache: cache mode of type &p9_cache_modes 67 * @cachetag: the tag of the cache associated with this session 68 * @fscache: session cookie associated with FS-Cache 69 * @options: copy of options string given by user 70 * @uname: string user name to mount hierarchy as 71 * @aname: mount specifier for remote hierarchy 72 * @maxdata: maximum data to be sent/recvd per protocol message 73 * @dfltuid: default numeric userid to mount hierarchy as 74 * @dfltgid: default numeric groupid to mount hierarchy as 75 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 76 * @clnt: reference to 9P network client instantiated for this session 77 * @slist: reference to list of registered 9p sessions 78 * 79 * This structure holds state for each session instance established during 80 * a sys_mount() . 81 * 82 * Bugs: there seems to be a lot of state which could be condensed and/or 83 * removed. 84 */ 85 86 struct v9fs_session_info { 87 /* options */ 88 unsigned char flags; 89 unsigned char nodev; 90 unsigned short debug; 91 unsigned int afid; 92 unsigned int cache; 93 #ifdef CONFIG_9P_FSCACHE 94 char *cachetag; 95 struct fscache_cookie *fscache; 96 #endif 97 98 char *uname; /* user name to mount as */ 99 char *aname; /* name of remote hierarchy being mounted */ 100 unsigned int maxdata; /* max data for client interface */ 101 unsigned int dfltuid; /* default uid/muid for legacy support */ 102 unsigned int dfltgid; /* default gid for legacy support */ 103 u32 uid; /* if ACCESS_SINGLE, the uid that has access */ 104 struct p9_client *clnt; /* 9p client */ 105 struct list_head slist; /* list of sessions registered with v9fs */ 106 struct backing_dev_info bdi; 107 struct rw_semaphore rename_sem; 108 }; 109 110 struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *, 111 char *); 112 void v9fs_session_close(struct v9fs_session_info *v9ses); 113 void v9fs_session_cancel(struct v9fs_session_info *v9ses); 114 void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 115 116 #define V9FS_MAGIC 0x01021997 117 118 /* other default globals */ 119 #define V9FS_PORT 564 120 #define V9FS_DEFUSER "nobody" 121 #define V9FS_DEFANAME "" 122 #define V9FS_DEFUID (-2) 123 #define V9FS_DEFGID (-2) 124 125 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 126 { 127 return (inode->i_sb->s_fs_info); 128 } 129 130 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 131 { 132 return v9ses->flags & V9FS_PROTO_2000U; 133 } 134 135 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 136 { 137 return v9ses->flags & V9FS_PROTO_2000L; 138 } 139