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 V9FS_NO_XATTR = 0x40 41 }; 42 43 /* possible values of ->cache */ 44 /** 45 * enum p9_cache_modes - user specified cache preferences 46 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 47 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 48 * 49 * eventually support loose, tight, time, session, default always none 50 */ 51 52 enum p9_cache_modes { 53 CACHE_NONE, 54 CACHE_READAHEAD, 55 CACHE_WRITEBACK, 56 CACHE_MMAP, 57 CACHE_LOOSE, 58 CACHE_FSCACHE, 59 nr__p9_cache_modes 60 }; 61 62 /** 63 * struct v9fs_session_info - per-instance session information 64 * @flags: session options of type &p9_session_flags 65 * @nodev: set to 1 to disable device mapping 66 * @debug: debug level 67 * @afid: authentication handle 68 * @cache: cache mode of type &p9_cache_modes 69 * @cachetag: the tag of the cache associated with this session 70 * @fscache: session cookie associated with FS-Cache 71 * @uname: string user name to mount hierarchy as 72 * @aname: mount specifier for remote hierarchy 73 * @maxdata: maximum data to be sent/recvd per protocol message 74 * @dfltuid: default numeric userid to mount hierarchy as 75 * @dfltgid: default numeric groupid to mount hierarchy as 76 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 77 * @clnt: reference to 9P network client instantiated for this session 78 * @slist: reference to list of registered 9p sessions 79 * 80 * This structure holds state for each session instance established during 81 * a sys_mount() . 82 * 83 * Bugs: there seems to be a lot of state which could be condensed and/or 84 * removed. 85 */ 86 87 struct v9fs_session_info { 88 /* options */ 89 unsigned char flags; 90 unsigned char nodev; 91 unsigned short debug; 92 unsigned int afid; 93 unsigned int cache; 94 #ifdef CONFIG_9P_FSCACHE 95 char *cachetag; 96 struct fscache_volume *fscache; 97 #endif 98 99 char *uname; /* user name to mount as */ 100 char *aname; /* name of remote hierarchy being mounted */ 101 unsigned int maxdata; /* max data for client interface */ 102 kuid_t dfltuid; /* default uid/muid for legacy support */ 103 kgid_t dfltgid; /* default gid for legacy support */ 104 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 105 struct p9_client *clnt; /* 9p client */ 106 struct list_head slist; /* list of sessions registered with v9fs */ 107 struct rw_semaphore rename_sem; 108 long session_lock_timeout; /* retry interval for blocking locks */ 109 }; 110 111 /* cache_validity flags */ 112 #define V9FS_INO_INVALID_ATTR 0x01 113 114 struct v9fs_inode { 115 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 116 struct p9_qid qid; 117 unsigned int cache_validity; 118 struct p9_fid *writeback_fid; 119 struct mutex v_mutex; 120 }; 121 122 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 123 { 124 return container_of(inode, struct v9fs_inode, netfs.inode); 125 } 126 127 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 128 { 129 #ifdef CONFIG_9P_FSCACHE 130 return netfs_i_cookie(&v9inode->netfs); 131 #else 132 return NULL; 133 #endif 134 } 135 136 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 137 { 138 #ifdef CONFIG_9P_FSCACHE 139 return v9ses->fscache; 140 #else 141 return NULL; 142 #endif 143 } 144 145 146 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 147 148 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 149 const char *dev_name, char *data); 150 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 151 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 152 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 153 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 154 unsigned int flags); 155 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 156 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 157 extern int v9fs_vfs_rename(struct mnt_idmap *idmap, 158 struct inode *old_dir, struct dentry *old_dentry, 159 struct inode *new_dir, struct dentry *new_dentry, 160 unsigned int flags); 161 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 162 struct p9_fid *fid, 163 struct super_block *sb, int new); 164 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 165 extern const struct inode_operations v9fs_file_inode_operations_dotl; 166 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 167 extern const struct netfs_request_ops v9fs_req_ops; 168 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 169 struct p9_fid *fid, 170 struct super_block *sb, int new); 171 172 /* other default globals */ 173 #define V9FS_PORT 564 174 #define V9FS_DEFUSER "nobody" 175 #define V9FS_DEFANAME "" 176 #define V9FS_DEFUID KUIDT_INIT(-2) 177 #define V9FS_DEFGID KGIDT_INIT(-2) 178 179 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 180 { 181 return inode->i_sb->s_fs_info; 182 } 183 184 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 185 { 186 return dentry->d_sb->s_fs_info; 187 } 188 189 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 190 { 191 return v9ses->flags & V9FS_PROTO_2000U; 192 } 193 194 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 195 { 196 return v9ses->flags & V9FS_PROTO_2000L; 197 } 198 199 /** 200 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 201 * issuing a attribute request 202 * @v9ses: session information 203 * @fid: fid to issue attribute request for 204 * @sb: superblock on which to create inode 205 * 206 */ 207 static inline struct inode * 208 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 209 struct super_block *sb) 210 { 211 if (v9fs_proto_dotl(v9ses)) 212 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 213 else 214 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 215 } 216 217 /** 218 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 219 * issuing a attribute request 220 * @v9ses: session information 221 * @fid: fid to issue attribute request for 222 * @sb: superblock on which to create inode 223 * 224 */ 225 static inline struct inode * 226 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 227 struct super_block *sb) 228 { 229 if (v9fs_proto_dotl(v9ses)) 230 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 231 else 232 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 233 } 234 235 #endif 236