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 #include <linux/netfs.h> 13 14 /** 15 * enum p9_session_flags - option flags for each 9P session 16 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions 17 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions 18 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy 19 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default) 20 * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client. 21 * @V9FS_ACCESS_ANY: use a single attach for all users 22 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options 23 * @V9FS_POSIX_ACL: POSIX ACLs are enforced 24 * 25 * Session flags reflect options selected by users at mount time 26 */ 27 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 28 V9FS_ACCESS_USER | \ 29 V9FS_ACCESS_CLIENT) 30 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 31 #define V9FS_ACL_MASK V9FS_POSIX_ACL 32 33 enum p9_session_flags { 34 V9FS_PROTO_2000U = 0x01, 35 V9FS_PROTO_2000L = 0x02, 36 V9FS_ACCESS_SINGLE = 0x04, 37 V9FS_ACCESS_USER = 0x08, 38 V9FS_ACCESS_CLIENT = 0x10, 39 V9FS_POSIX_ACL = 0x20 40 }; 41 42 /* possible values of ->cache */ 43 /** 44 * enum p9_cache_modes - user specified cache preferences 45 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 46 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 47 * 48 * eventually support loose, tight, time, session, default always none 49 */ 50 51 enum p9_cache_modes { 52 CACHE_NONE, 53 CACHE_READAHEAD, 54 CACHE_WRITEBACK, 55 CACHE_MMAP, 56 CACHE_LOOSE, 57 CACHE_FSCACHE, 58 nr__p9_cache_modes 59 }; 60 61 /** 62 * struct v9fs_session_info - per-instance session information 63 * @flags: session options of type &p9_session_flags 64 * @nodev: set to 1 to disable device mapping 65 * @debug: debug level 66 * @afid: authentication handle 67 * @cache: cache mode of type &p9_cache_modes 68 * @cachetag: the tag of the cache associated with this session 69 * @fscache: session cookie associated with FS-Cache 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_volume *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 kuid_t dfltuid; /* default uid/muid for legacy support */ 102 kgid_t dfltgid; /* default gid for legacy support */ 103 kuid_t 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 rw_semaphore rename_sem; 107 long session_lock_timeout; /* retry interval for blocking locks */ 108 }; 109 110 /* cache_validity flags */ 111 #define V9FS_INO_INVALID_ATTR 0x01 112 113 struct v9fs_inode { 114 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 115 struct p9_qid qid; 116 unsigned int cache_validity; 117 struct p9_fid *writeback_fid; 118 struct mutex v_mutex; 119 }; 120 121 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 122 { 123 return container_of(inode, struct v9fs_inode, netfs.inode); 124 } 125 126 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 127 { 128 #ifdef CONFIG_9P_FSCACHE 129 return netfs_i_cookie(&v9inode->netfs); 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 mnt_idmap *idmap, 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 const struct netfs_request_ops v9fs_req_ops; 167 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 168 struct p9_fid *fid, 169 struct super_block *sb, int new); 170 171 /* other default globals */ 172 #define V9FS_PORT 564 173 #define V9FS_DEFUSER "nobody" 174 #define V9FS_DEFANAME "" 175 #define V9FS_DEFUID KUIDT_INIT(-2) 176 #define V9FS_DEFGID KGIDT_INIT(-2) 177 178 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 179 { 180 return inode->i_sb->s_fs_info; 181 } 182 183 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 184 { 185 return dentry->d_sb->s_fs_info; 186 } 187 188 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 189 { 190 return v9ses->flags & V9FS_PROTO_2000U; 191 } 192 193 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 194 { 195 return v9ses->flags & V9FS_PROTO_2000L; 196 } 197 198 /** 199 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 200 * issuing a attribute request 201 * @v9ses: session information 202 * @fid: fid to issue attribute request for 203 * @sb: superblock on which to create inode 204 * 205 */ 206 static inline struct inode * 207 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 208 struct super_block *sb) 209 { 210 if (v9fs_proto_dotl(v9ses)) 211 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 212 else 213 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 214 } 215 216 /** 217 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 218 * issuing a attribute request 219 * @v9ses: session information 220 * @fid: fid to issue attribute request for 221 * @sb: superblock on which to create inode 222 * 223 */ 224 static inline struct inode * 225 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 226 struct super_block *sb) 227 { 228 if (v9fs_proto_dotl(v9ses)) 229 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 230 else 231 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 232 } 233 234 #endif 235