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 #ifndef FS_9P_V9FS_H 24 #define FS_9P_V9FS_H 25 26 #include <linux/backing-dev.h> 27 28 /** 29 * enum p9_session_flags - option flags for each 9P session 30 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions 31 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions 32 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy 33 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default) 34 * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client. 35 * @V9FS_ACCESS_ANY: use a single attach for all users 36 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options 37 * @V9FS_POSIX_ACL: POSIX ACLs are enforced 38 * 39 * Session flags reflect options selected by users at mount time 40 */ 41 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 42 V9FS_ACCESS_USER | \ 43 V9FS_ACCESS_CLIENT) 44 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 45 #define V9FS_ACL_MASK V9FS_POSIX_ACL 46 47 enum p9_session_flags { 48 V9FS_PROTO_2000U = 0x01, 49 V9FS_PROTO_2000L = 0x02, 50 V9FS_ACCESS_SINGLE = 0x04, 51 V9FS_ACCESS_USER = 0x08, 52 V9FS_ACCESS_CLIENT = 0x10, 53 V9FS_POSIX_ACL = 0x20 54 }; 55 56 /* possible values of ->cache */ 57 /** 58 * enum p9_cache_modes - user specified cache preferences 59 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 60 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 61 * 62 * eventually support loose, tight, time, session, default always none 63 */ 64 65 enum p9_cache_modes { 66 CACHE_NONE, 67 CACHE_MMAP, 68 CACHE_LOOSE, 69 CACHE_FSCACHE, 70 nr__p9_cache_modes 71 }; 72 73 /** 74 * struct v9fs_session_info - per-instance session information 75 * @flags: session options of type &p9_session_flags 76 * @nodev: set to 1 to disable device mapping 77 * @debug: debug level 78 * @afid: authentication handle 79 * @cache: cache mode of type &p9_cache_modes 80 * @cachetag: the tag of the cache associated with this session 81 * @fscache: session cookie associated with FS-Cache 82 * @uname: string user name to mount hierarchy as 83 * @aname: mount specifier for remote hierarchy 84 * @maxdata: maximum data to be sent/recvd per protocol message 85 * @dfltuid: default numeric userid to mount hierarchy as 86 * @dfltgid: default numeric groupid to mount hierarchy as 87 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 88 * @clnt: reference to 9P network client instantiated for this session 89 * @slist: reference to list of registered 9p sessions 90 * 91 * This structure holds state for each session instance established during 92 * a sys_mount() . 93 * 94 * Bugs: there seems to be a lot of state which could be condensed and/or 95 * removed. 96 */ 97 98 struct v9fs_session_info { 99 /* options */ 100 unsigned char flags; 101 unsigned char nodev; 102 unsigned short debug; 103 unsigned int afid; 104 unsigned int cache; 105 #ifdef CONFIG_9P_FSCACHE 106 char *cachetag; 107 struct fscache_cookie *fscache; 108 #endif 109 110 char *uname; /* user name to mount as */ 111 char *aname; /* name of remote hierarchy being mounted */ 112 unsigned int maxdata; /* max data for client interface */ 113 kuid_t dfltuid; /* default uid/muid for legacy support */ 114 kgid_t dfltgid; /* default gid for legacy support */ 115 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 116 struct p9_client *clnt; /* 9p client */ 117 struct list_head slist; /* list of sessions registered with v9fs */ 118 struct rw_semaphore rename_sem; 119 long session_lock_timeout; /* retry interval for blocking locks */ 120 }; 121 122 /* cache_validity flags */ 123 #define V9FS_INO_INVALID_ATTR 0x01 124 125 struct v9fs_inode { 126 #ifdef CONFIG_9P_FSCACHE 127 struct mutex fscache_lock; 128 struct fscache_cookie *fscache; 129 #endif 130 struct p9_qid qid; 131 unsigned int cache_validity; 132 struct p9_fid *writeback_fid; 133 struct mutex v_mutex; 134 struct inode vfs_inode; 135 }; 136 137 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 138 { 139 return container_of(inode, struct v9fs_inode, vfs_inode); 140 } 141 142 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 143 144 struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *, 145 char *); 146 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 147 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 148 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 149 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 150 unsigned int flags); 151 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 152 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 153 extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, 154 struct inode *new_dir, struct dentry *new_dentry, 155 unsigned int flags); 156 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 157 struct p9_fid *fid, 158 struct super_block *sb, int new); 159 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 160 extern const struct inode_operations v9fs_file_inode_operations_dotl; 161 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 162 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 163 struct p9_fid *fid, 164 struct super_block *sb, int new); 165 166 /* other default globals */ 167 #define V9FS_PORT 564 168 #define V9FS_DEFUSER "nobody" 169 #define V9FS_DEFANAME "" 170 #define V9FS_DEFUID KUIDT_INIT(-2) 171 #define V9FS_DEFGID KGIDT_INIT(-2) 172 173 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 174 { 175 return (inode->i_sb->s_fs_info); 176 } 177 178 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 179 { 180 return dentry->d_sb->s_fs_info; 181 } 182 183 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 184 { 185 return v9ses->flags & V9FS_PROTO_2000U; 186 } 187 188 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 189 { 190 return v9ses->flags & V9FS_PROTO_2000L; 191 } 192 193 /** 194 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 195 * issuing a attribute request 196 * @v9ses: session information 197 * @fid: fid to issue attribute request for 198 * @sb: superblock on which to create inode 199 * 200 */ 201 static inline struct inode * 202 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 203 struct super_block *sb) 204 { 205 if (v9fs_proto_dotl(v9ses)) 206 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 207 else 208 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 209 } 210 211 /** 212 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 213 * issuing a attribute request 214 * @v9ses: session information 215 * @fid: fid to issue attribute request for 216 * @sb: superblock on which to create inode 217 * 218 */ 219 static inline struct inode * 220 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 221 struct super_block *sb) 222 { 223 if (v9fs_proto_dotl(v9ses)) 224 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 225 else 226 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 227 } 228 229 #endif 230