1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * V9FS definitions. 4 * 5 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> 6 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> 7 */ 8 #ifndef FS_9P_V9FS_H 9 #define FS_9P_V9FS_H 10 11 #include <linux/backing-dev.h> 12 13 /** 14 * enum p9_session_flags - option flags for each 9P session 15 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions 16 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions 17 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy 18 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default) 19 * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client. 20 * @V9FS_ACCESS_ANY: use a single attach for all users 21 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options 22 * @V9FS_POSIX_ACL: POSIX ACLs are enforced 23 * 24 * Session flags reflect options selected by users at mount time 25 */ 26 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 27 V9FS_ACCESS_USER | \ 28 V9FS_ACCESS_CLIENT) 29 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 30 #define V9FS_ACL_MASK V9FS_POSIX_ACL 31 32 enum p9_session_flags { 33 V9FS_PROTO_2000U = 0x01, 34 V9FS_PROTO_2000L = 0x02, 35 V9FS_ACCESS_SINGLE = 0x04, 36 V9FS_ACCESS_USER = 0x08, 37 V9FS_ACCESS_CLIENT = 0x10, 38 V9FS_POSIX_ACL = 0x20 39 }; 40 41 /* possible values of ->cache */ 42 /** 43 * enum p9_cache_modes - user specified cache preferences 44 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 45 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 46 * 47 * eventually support loose, tight, time, session, default always none 48 */ 49 50 enum p9_cache_modes { 51 CACHE_NONE, 52 CACHE_MMAP, 53 CACHE_LOOSE, 54 CACHE_FSCACHE, 55 nr__p9_cache_modes 56 }; 57 58 /** 59 * struct v9fs_session_info - per-instance session information 60 * @flags: session options of type &p9_session_flags 61 * @nodev: set to 1 to disable device mapping 62 * @debug: debug level 63 * @afid: authentication handle 64 * @cache: cache mode of type &p9_cache_modes 65 * @cachetag: the tag of the cache associated with this session 66 * @fscache: session cookie associated with FS-Cache 67 * @uname: string user name to mount hierarchy as 68 * @aname: mount specifier for remote hierarchy 69 * @maxdata: maximum data to be sent/recvd per protocol message 70 * @dfltuid: default numeric userid to mount hierarchy as 71 * @dfltgid: default numeric groupid to mount hierarchy as 72 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 73 * @clnt: reference to 9P network client instantiated for this session 74 * @slist: reference to list of registered 9p sessions 75 * 76 * This structure holds state for each session instance established during 77 * a sys_mount() . 78 * 79 * Bugs: there seems to be a lot of state which could be condensed and/or 80 * removed. 81 */ 82 83 struct v9fs_session_info { 84 /* options */ 85 unsigned char flags; 86 unsigned char nodev; 87 unsigned short debug; 88 unsigned int afid; 89 unsigned int cache; 90 #ifdef CONFIG_9P_FSCACHE 91 char *cachetag; 92 struct fscache_volume *fscache; 93 #endif 94 95 char *uname; /* user name to mount as */ 96 char *aname; /* name of remote hierarchy being mounted */ 97 unsigned int maxdata; /* max data for client interface */ 98 kuid_t dfltuid; /* default uid/muid for legacy support */ 99 kgid_t dfltgid; /* default gid for legacy support */ 100 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 101 struct p9_client *clnt; /* 9p client */ 102 struct list_head slist; /* list of sessions registered with v9fs */ 103 struct rw_semaphore rename_sem; 104 long session_lock_timeout; /* retry interval for blocking locks */ 105 }; 106 107 /* cache_validity flags */ 108 #define V9FS_INO_INVALID_ATTR 0x01 109 110 struct v9fs_inode { 111 #ifdef CONFIG_9P_FSCACHE 112 struct fscache_cookie *fscache; 113 #endif 114 struct p9_qid qid; 115 unsigned int cache_validity; 116 struct p9_fid *writeback_fid; 117 struct mutex v_mutex; 118 struct inode vfs_inode; 119 }; 120 121 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 122 { 123 return container_of(inode, struct v9fs_inode, vfs_inode); 124 } 125 126 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 127 { 128 #ifdef CONFIG_9P_FSCACHE 129 return v9inode->fscache; 130 #else 131 return NULL; 132 #endif 133 } 134 135 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 136 { 137 #ifdef CONFIG_9P_FSCACHE 138 return v9ses->fscache; 139 #else 140 return NULL; 141 #endif 142 } 143 144 145 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 146 147 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 148 const char *dev_name, char *data); 149 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 150 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 151 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 152 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 153 unsigned int flags); 154 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 155 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 156 extern int v9fs_vfs_rename(struct user_namespace *mnt_userns, 157 struct inode *old_dir, struct dentry *old_dentry, 158 struct inode *new_dir, struct dentry *new_dentry, 159 unsigned int flags); 160 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 161 struct p9_fid *fid, 162 struct super_block *sb, int new); 163 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 164 extern const struct inode_operations v9fs_file_inode_operations_dotl; 165 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 166 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 167 struct p9_fid *fid, 168 struct super_block *sb, int new); 169 170 /* other default globals */ 171 #define V9FS_PORT 564 172 #define V9FS_DEFUSER "nobody" 173 #define V9FS_DEFANAME "" 174 #define V9FS_DEFUID KUIDT_INIT(-2) 175 #define V9FS_DEFGID KGIDT_INIT(-2) 176 177 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 178 { 179 return inode->i_sb->s_fs_info; 180 } 181 182 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 183 { 184 return dentry->d_sb->s_fs_info; 185 } 186 187 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 188 { 189 return v9ses->flags & V9FS_PROTO_2000U; 190 } 191 192 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 193 { 194 return v9ses->flags & V9FS_PROTO_2000L; 195 } 196 197 /** 198 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 199 * issuing a attribute request 200 * @v9ses: session information 201 * @fid: fid to issue attribute request for 202 * @sb: superblock on which to create inode 203 * 204 */ 205 static inline struct inode * 206 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 207 struct super_block *sb) 208 { 209 if (v9fs_proto_dotl(v9ses)) 210 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 211 else 212 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 213 } 214 215 /** 216 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 217 * issuing a attribute request 218 * @v9ses: session information 219 * @fid: fid to issue attribute request for 220 * @sb: superblock on which to create inode 221 * 222 */ 223 static inline struct inode * 224 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 225 struct super_block *sb) 226 { 227 if (v9fs_proto_dotl(v9ses)) 228 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 229 else 230 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 231 } 232 233 #endif 234