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 V9FS_IGNORE_QV = 0x80, /* ignore qid.version for cache hints */ 42 V9FS_DIRECT_IO = 0x100, 43 V9FS_SYNC = 0x200 44 }; 45 46 /* possible values of ->cache */ 47 /** 48 * enum p9_cache_modes - user specified cache preferences 49 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 50 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 51 * 52 * eventually support loose, tight, time, session, default always none 53 */ 54 55 enum p9_cache_modes { 56 CACHE_NONE, 57 CACHE_READAHEAD, 58 CACHE_WRITEBACK, 59 CACHE_MMAP, 60 CACHE_LOOSE, 61 CACHE_FSCACHE, 62 nr__p9_cache_modes 63 }; 64 65 /** 66 * struct v9fs_session_info - per-instance session information 67 * @flags: session options of type &p9_session_flags 68 * @nodev: set to 1 to disable device mapping 69 * @debug: debug level 70 * @afid: authentication handle 71 * @cache: cache mode of type &p9_cache_modes 72 * @cachetag: the tag of the cache associated with this session 73 * @fscache: session cookie associated with FS-Cache 74 * @uname: string user name to mount hierarchy as 75 * @aname: mount specifier for remote hierarchy 76 * @maxdata: maximum data to be sent/recvd per protocol message 77 * @dfltuid: default numeric userid to mount hierarchy as 78 * @dfltgid: default numeric groupid to mount hierarchy as 79 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 80 * @clnt: reference to 9P network client instantiated for this session 81 * @slist: reference to list of registered 9p sessions 82 * 83 * This structure holds state for each session instance established during 84 * a sys_mount() . 85 * 86 * Bugs: there seems to be a lot of state which could be condensed and/or 87 * removed. 88 */ 89 90 struct v9fs_session_info { 91 /* options */ 92 unsigned char flags; 93 unsigned char nodev; 94 unsigned short debug; 95 unsigned int afid; 96 unsigned int cache; 97 #ifdef CONFIG_9P_FSCACHE 98 char *cachetag; 99 struct fscache_volume *fscache; 100 #endif 101 102 char *uname; /* user name to mount as */ 103 char *aname; /* name of remote hierarchy being mounted */ 104 unsigned int maxdata; /* max data for client interface */ 105 kuid_t dfltuid; /* default uid/muid for legacy support */ 106 kgid_t dfltgid; /* default gid for legacy support */ 107 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 108 struct p9_client *clnt; /* 9p client */ 109 struct list_head slist; /* list of sessions registered with v9fs */ 110 struct rw_semaphore rename_sem; 111 long session_lock_timeout; /* retry interval for blocking locks */ 112 }; 113 114 /* cache_validity flags */ 115 #define V9FS_INO_INVALID_ATTR 0x01 116 117 struct v9fs_inode { 118 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 119 struct p9_qid qid; 120 unsigned int cache_validity; 121 struct p9_fid *writeback_fid; 122 struct mutex v_mutex; 123 }; 124 125 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 126 { 127 return container_of(inode, struct v9fs_inode, netfs.inode); 128 } 129 130 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 131 { 132 #ifdef CONFIG_9P_FSCACHE 133 return netfs_i_cookie(&v9inode->netfs); 134 #else 135 return NULL; 136 #endif 137 } 138 139 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 140 { 141 #ifdef CONFIG_9P_FSCACHE 142 return v9ses->fscache; 143 #else 144 return NULL; 145 #endif 146 } 147 148 149 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 150 151 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 152 const char *dev_name, char *data); 153 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 154 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 155 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 156 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 157 unsigned int flags); 158 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 159 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 160 extern int v9fs_vfs_rename(struct mnt_idmap *idmap, 161 struct inode *old_dir, struct dentry *old_dentry, 162 struct inode *new_dir, struct dentry *new_dentry, 163 unsigned int flags); 164 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 165 struct p9_fid *fid, 166 struct super_block *sb, int new); 167 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 168 extern const struct inode_operations v9fs_file_inode_operations_dotl; 169 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 170 extern const struct netfs_request_ops v9fs_req_ops; 171 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 172 struct p9_fid *fid, 173 struct super_block *sb, int new); 174 175 /* other default globals */ 176 #define V9FS_PORT 564 177 #define V9FS_DEFUSER "nobody" 178 #define V9FS_DEFANAME "" 179 #define V9FS_DEFUID KUIDT_INIT(-2) 180 #define V9FS_DEFGID KGIDT_INIT(-2) 181 182 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 183 { 184 return inode->i_sb->s_fs_info; 185 } 186 187 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 188 { 189 return dentry->d_sb->s_fs_info; 190 } 191 192 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 193 { 194 return v9ses->flags & V9FS_PROTO_2000U; 195 } 196 197 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 198 { 199 return v9ses->flags & V9FS_PROTO_2000L; 200 } 201 202 /** 203 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 204 * issuing a attribute request 205 * @v9ses: session information 206 * @fid: fid to issue attribute request for 207 * @sb: superblock on which to create inode 208 * 209 */ 210 static inline struct inode * 211 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 212 struct super_block *sb) 213 { 214 if (v9fs_proto_dotl(v9ses)) 215 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 216 else 217 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 218 } 219 220 /** 221 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 222 * issuing a attribute request 223 * @v9ses: session information 224 * @fid: fid to issue attribute request for 225 * @sb: superblock on which to create inode 226 * 227 */ 228 static inline struct inode * 229 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 230 struct super_block *sb) 231 { 232 if (v9fs_proto_dotl(v9ses)) 233 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 234 else 235 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 236 } 237 238 #endif 239