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 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 37 V9FS_ACCESS_USER | \ 38 V9FS_ACCESS_CLIENT) 39 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 40 41 enum p9_session_flags { 42 V9FS_PROTO_2000U = 0x01, 43 V9FS_PROTO_2000L = 0x02, 44 V9FS_ACCESS_SINGLE = 0x04, 45 V9FS_ACCESS_USER = 0x08, 46 V9FS_ACCESS_CLIENT = 0x10 47 }; 48 49 /* possible values of ->cache */ 50 /** 51 * enum p9_cache_modes - user specified cache preferences 52 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 53 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 54 * 55 * eventually support loose, tight, time, session, default always none 56 */ 57 58 enum p9_cache_modes { 59 CACHE_NONE, 60 CACHE_LOOSE, 61 CACHE_FSCACHE, 62 }; 63 64 /** 65 * struct v9fs_session_info - per-instance session information 66 * @flags: session options of type &p9_session_flags 67 * @nodev: set to 1 to disable device mapping 68 * @debug: debug level 69 * @afid: authentication handle 70 * @cache: cache mode of type &p9_cache_modes 71 * @cachetag: the tag of the cache associated with this session 72 * @fscache: session cookie associated with FS-Cache 73 * @options: copy of options string given by user 74 * @uname: string user name to mount hierarchy as 75 * @aname: mount specifier for remote hierarchy 76 * @maxdata: maximum data to be sent/recvd per protocol message 77 * @dfltuid: default numeric userid to mount hierarchy as 78 * @dfltgid: default numeric groupid to mount hierarchy as 79 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 80 * @clnt: reference to 9P network client instantiated for this session 81 * @slist: reference to list of registered 9p sessions 82 * 83 * This structure holds state for each session instance established during 84 * a sys_mount() . 85 * 86 * Bugs: there seems to be a lot of state which could be condensed and/or 87 * removed. 88 */ 89 90 struct v9fs_session_info { 91 /* options */ 92 unsigned char flags; 93 unsigned char nodev; 94 unsigned short debug; 95 unsigned int afid; 96 unsigned int cache; 97 #ifdef CONFIG_9P_FSCACHE 98 char *cachetag; 99 struct fscache_cookie *fscache; 100 #endif 101 102 char *uname; /* user name to mount as */ 103 char *aname; /* name of remote hierarchy being mounted */ 104 unsigned int maxdata; /* max data for client interface */ 105 unsigned int dfltuid; /* default uid/muid for legacy support */ 106 unsigned int dfltgid; /* default gid for legacy support */ 107 u32 uid; /* if ACCESS_SINGLE, the uid that has access */ 108 struct p9_client *clnt; /* 9p client */ 109 struct list_head slist; /* list of sessions registered with v9fs */ 110 struct backing_dev_info bdi; 111 struct rw_semaphore rename_sem; 112 }; 113 114 struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *, 115 char *); 116 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 117 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 118 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 119 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 120 struct nameidata *nameidata); 121 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 122 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 123 extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, 124 struct inode *new_dir, struct dentry *new_dentry); 125 extern void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, 126 void *p); 127 extern struct inode *v9fs_inode(struct v9fs_session_info *v9ses, 128 struct p9_fid *fid, 129 struct super_block *sb); 130 131 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 132 extern const struct inode_operations v9fs_file_inode_operations_dotl; 133 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 134 extern struct inode *v9fs_inode_dotl(struct v9fs_session_info *v9ses, 135 struct p9_fid *fid, 136 struct super_block *sb); 137 138 /* other default globals */ 139 #define V9FS_PORT 564 140 #define V9FS_DEFUSER "nobody" 141 #define V9FS_DEFANAME "" 142 #define V9FS_DEFUID (-2) 143 #define V9FS_DEFGID (-2) 144 145 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 146 { 147 return (inode->i_sb->s_fs_info); 148 } 149 150 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 151 { 152 return v9ses->flags & V9FS_PROTO_2000U; 153 } 154 155 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 156 { 157 return v9ses->flags & V9FS_PROTO_2000L; 158 } 159 160 /** 161 * v9fs_inode_from_fid - Helper routine to populate an inode by 162 * issuing a attribute request 163 * @v9ses: session information 164 * @fid: fid to issue attribute request for 165 * @sb: superblock on which to create inode 166 * 167 */ 168 static inline struct inode * 169 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 170 struct super_block *sb) 171 { 172 if (v9fs_proto_dotl(v9ses)) 173 return v9fs_inode_dotl(v9ses, fid, sb); 174 else 175 return v9fs_inode(v9ses, fid, sb); 176 } 177