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_CLIENT: Just like user, but access check is performed on client. 32 * @V9FS_ACCESS_ANY: use a single attach for all users 33 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options 34 * @V9FS_POSIX_ACL: POSIX ACLs are enforced 35 * 36 * Session flags reflect options selected by users at mount time 37 */ 38 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 39 V9FS_ACCESS_USER | \ 40 V9FS_ACCESS_CLIENT) 41 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 42 #define V9FS_ACL_MASK V9FS_POSIX_ACL 43 44 enum p9_session_flags { 45 V9FS_PROTO_2000U = 0x01, 46 V9FS_PROTO_2000L = 0x02, 47 V9FS_ACCESS_SINGLE = 0x04, 48 V9FS_ACCESS_USER = 0x08, 49 V9FS_ACCESS_CLIENT = 0x10, 50 V9FS_POSIX_ACL = 0x20 51 }; 52 53 /* possible values of ->cache */ 54 /** 55 * enum p9_cache_modes - user specified cache preferences 56 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 57 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 58 * 59 * eventually support loose, tight, time, session, default always none 60 */ 61 62 enum p9_cache_modes { 63 CACHE_NONE, 64 CACHE_LOOSE, 65 CACHE_FSCACHE, 66 }; 67 68 /** 69 * struct v9fs_session_info - per-instance session information 70 * @flags: session options of type &p9_session_flags 71 * @nodev: set to 1 to disable device mapping 72 * @debug: debug level 73 * @afid: authentication handle 74 * @cache: cache mode of type &p9_cache_modes 75 * @cachetag: the tag of the cache associated with this session 76 * @fscache: session cookie associated with FS-Cache 77 * @options: copy of options string given by user 78 * @uname: string user name to mount hierarchy as 79 * @aname: mount specifier for remote hierarchy 80 * @maxdata: maximum data to be sent/recvd per protocol message 81 * @dfltuid: default numeric userid to mount hierarchy as 82 * @dfltgid: default numeric groupid to mount hierarchy as 83 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 84 * @clnt: reference to 9P network client instantiated for this session 85 * @slist: reference to list of registered 9p sessions 86 * 87 * This structure holds state for each session instance established during 88 * a sys_mount() . 89 * 90 * Bugs: there seems to be a lot of state which could be condensed and/or 91 * removed. 92 */ 93 94 struct v9fs_session_info { 95 /* options */ 96 unsigned char flags; 97 unsigned char nodev; 98 unsigned short debug; 99 unsigned int afid; 100 unsigned int cache; 101 #ifdef CONFIG_9P_FSCACHE 102 char *cachetag; 103 struct fscache_cookie *fscache; 104 #endif 105 106 char *uname; /* user name to mount as */ 107 char *aname; /* name of remote hierarchy being mounted */ 108 unsigned int maxdata; /* max data for client interface */ 109 unsigned int dfltuid; /* default uid/muid for legacy support */ 110 unsigned int dfltgid; /* default gid for legacy support */ 111 u32 uid; /* if ACCESS_SINGLE, the uid that has access */ 112 struct p9_client *clnt; /* 9p client */ 113 struct list_head slist; /* list of sessions registered with v9fs */ 114 struct backing_dev_info bdi; 115 struct rw_semaphore rename_sem; 116 struct p9_fid *root_fid; /* Used for file system sync */ 117 }; 118 119 struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *, 120 char *); 121 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 122 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 123 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 124 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 125 struct nameidata *nameidata); 126 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 127 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 128 extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, 129 struct inode *new_dir, struct dentry *new_dentry); 130 extern void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, 131 void *p); 132 extern struct inode *v9fs_inode(struct v9fs_session_info *v9ses, 133 struct p9_fid *fid, 134 struct super_block *sb); 135 136 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 137 extern const struct inode_operations v9fs_file_inode_operations_dotl; 138 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 139 extern struct inode *v9fs_inode_dotl(struct v9fs_session_info *v9ses, 140 struct p9_fid *fid, 141 struct super_block *sb); 142 143 /* other default globals */ 144 #define V9FS_PORT 564 145 #define V9FS_DEFUSER "nobody" 146 #define V9FS_DEFANAME "" 147 #define V9FS_DEFUID (-2) 148 #define V9FS_DEFGID (-2) 149 150 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 151 { 152 return (inode->i_sb->s_fs_info); 153 } 154 155 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 156 { 157 return v9ses->flags & V9FS_PROTO_2000U; 158 } 159 160 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 161 { 162 return v9ses->flags & V9FS_PROTO_2000L; 163 } 164 165 /** 166 * v9fs_inode_from_fid - Helper routine to populate an inode by 167 * issuing a attribute request 168 * @v9ses: session information 169 * @fid: fid to issue attribute request for 170 * @sb: superblock on which to create inode 171 * 172 */ 173 static inline struct inode * 174 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 175 struct super_block *sb) 176 { 177 if (v9fs_proto_dotl(v9ses)) 178 return v9fs_inode_dotl(v9ses, fid, sb); 179 else 180 return v9fs_inode(v9ses, fid, sb); 181 } 182