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 #include <linux/fs_parser.h> 14 #include <net/9p/client.h> 15 #include <net/9p/transport.h> 16 17 /** 18 * enum p9_session_flags - option flags for each 9P session 19 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions 20 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions 21 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy 22 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default) 23 * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client. 24 * @V9FS_ACCESS_ANY: use a single attach for all users 25 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options 26 * @V9FS_POSIX_ACL: POSIX ACLs are enforced 27 * 28 * Session flags reflect options selected by users at mount time 29 */ 30 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 31 V9FS_ACCESS_USER | \ 32 V9FS_ACCESS_CLIENT) 33 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 34 #define V9FS_ACL_MASK V9FS_POSIX_ACL 35 36 enum p9_session_flags { 37 V9FS_PROTO_2000U = 0x01, 38 V9FS_PROTO_2000L = 0x02, 39 V9FS_ACCESS_SINGLE = 0x04, 40 V9FS_ACCESS_USER = 0x08, 41 V9FS_ACCESS_CLIENT = 0x10, 42 V9FS_POSIX_ACL = 0x20, 43 V9FS_NO_XATTR = 0x40, 44 V9FS_IGNORE_QV = 0x80, /* ignore qid.version for cache hints */ 45 V9FS_DIRECT_IO = 0x100, 46 V9FS_SYNC = 0x200 47 }; 48 49 /** 50 * enum p9_cache_shortcuts - human readable cache preferences 51 * @CACHE_SC_NONE: disable all caches 52 * @CACHE_SC_READAHEAD: only provide caching for readahead 53 * @CACHE_SC_MMAP: provide caching to enable mmap 54 * @CACHE_SC_LOOSE: non-coherent caching for files and meta data 55 * @CACHE_SC_FSCACHE: persistent non-coherent caching for files and meta-data 56 * 57 */ 58 59 enum p9_cache_shortcuts { 60 CACHE_SC_NONE = 0b00000000, 61 CACHE_SC_READAHEAD = 0b00000001, 62 CACHE_SC_MMAP = 0b00000101, 63 CACHE_SC_LOOSE = 0b00001111, 64 CACHE_SC_FSCACHE = 0b10001111, 65 }; 66 67 /** 68 * enum p9_cache_bits - possible values of ->cache 69 * @CACHE_NONE: caches disabled 70 * @CACHE_FILE: file caching (open to close) 71 * @CACHE_META: meta-data and directory caching 72 * @CACHE_WRITEBACK: write-back caching for files 73 * @CACHE_LOOSE: don't check cache consistency 74 * @CACHE_FSCACHE: local persistent caches 75 * 76 */ 77 78 enum p9_cache_bits { 79 CACHE_NONE = 0b00000000, 80 CACHE_FILE = 0b00000001, 81 CACHE_META = 0b00000010, 82 CACHE_WRITEBACK = 0b00000100, 83 CACHE_LOOSE = 0b00001000, 84 CACHE_FSCACHE = 0b10000000, 85 }; 86 87 /** 88 * struct v9fs_session_info - per-instance session information 89 * @flags: session options of type &p9_session_flags 90 * @nodev: set to 1 to disable device mapping 91 * @debug: debug level 92 * @afid: authentication handle 93 * @cache: cache mode of type &p9_cache_bits 94 * @cachetag: the tag of the cache associated with this session 95 * @fscache: session cookie associated with FS-Cache 96 * @uname: string user name to mount hierarchy as 97 * @aname: mount specifier for remote hierarchy 98 * @maxdata: maximum data to be sent/recvd per protocol message 99 * @dfltuid: default numeric userid to mount hierarchy as 100 * @dfltgid: default numeric groupid to mount hierarchy as 101 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 102 * @clnt: reference to 9P network client instantiated for this session 103 * @slist: reference to list of registered 9p sessions 104 * 105 * This structure holds state for each session instance established during 106 * a sys_mount() . 107 * 108 * Bugs: there seems to be a lot of state which could be condensed and/or 109 * removed. 110 */ 111 112 struct v9fs_session_info { 113 /* options */ 114 unsigned int flags; 115 unsigned char nodev; 116 unsigned short debug; 117 unsigned int afid; 118 unsigned int cache; 119 #ifdef CONFIG_9P_FSCACHE 120 char *cachetag; 121 struct fscache_volume *fscache; 122 #endif 123 124 char *uname; /* user name to mount as */ 125 char *aname; /* name of remote hierarchy being mounted */ 126 unsigned int maxdata; /* max data for client interface */ 127 kuid_t dfltuid; /* default uid/muid for legacy support */ 128 kgid_t dfltgid; /* default gid for legacy support */ 129 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 130 struct p9_client *clnt; /* 9p client */ 131 struct list_head slist; /* list of sessions registered with v9fs */ 132 struct rw_semaphore rename_sem; 133 long session_lock_timeout; /* retry interval for blocking locks */ 134 }; 135 136 /* cache_validity flags */ 137 #define V9FS_INO_INVALID_ATTR 0x01 138 139 struct v9fs_inode { 140 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 141 struct p9_qid qid; 142 unsigned int cache_validity; 143 struct mutex v_mutex; 144 }; 145 146 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 147 { 148 return container_of(inode, struct v9fs_inode, netfs.inode); 149 } 150 151 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 152 { 153 #ifdef CONFIG_9P_FSCACHE 154 return netfs_i_cookie(&v9inode->netfs); 155 #else 156 return NULL; 157 #endif 158 } 159 160 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 161 { 162 #ifdef CONFIG_9P_FSCACHE 163 return v9ses->fscache; 164 #else 165 return NULL; 166 #endif 167 } 168 169 extern const struct fs_parameter_spec v9fs_param_spec[]; 170 171 extern int v9fs_parse_param(struct fs_context *fc, struct fs_parameter *param); 172 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 173 174 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 175 struct fs_context *fc); 176 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 177 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 178 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 179 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 180 unsigned int flags); 181 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 182 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 183 extern int v9fs_vfs_rename(struct mnt_idmap *idmap, 184 struct inode *old_dir, struct dentry *old_dentry, 185 struct inode *new_dir, struct dentry *new_dentry, 186 unsigned int flags); 187 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 188 struct p9_fid *fid, 189 struct super_block *sb, int new); 190 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 191 extern const struct inode_operations v9fs_file_inode_operations_dotl; 192 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 193 extern const struct netfs_request_ops v9fs_req_ops; 194 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 195 struct p9_fid *fid, 196 struct super_block *sb, int new); 197 198 /* other default globals */ 199 #define V9FS_PORT 564 200 #define V9FS_DEFUSER "nobody" 201 #define V9FS_DEFANAME "" 202 #define V9FS_DEFUID KUIDT_INIT(-2) 203 #define V9FS_DEFGID KGIDT_INIT(-2) 204 205 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 206 { 207 return inode->i_sb->s_fs_info; 208 } 209 210 static inline struct v9fs_session_info *v9fs_dentry2v9ses(const struct dentry *dentry) 211 { 212 return dentry->d_sb->s_fs_info; 213 } 214 215 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 216 { 217 return v9ses->flags & V9FS_PROTO_2000U; 218 } 219 220 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 221 { 222 return v9ses->flags & V9FS_PROTO_2000L; 223 } 224 225 /** 226 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 227 * issuing a attribute request 228 * @v9ses: session information 229 * @fid: fid to issue attribute request for 230 * @sb: superblock on which to create inode 231 * 232 */ 233 static inline struct inode * 234 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 235 struct super_block *sb) 236 { 237 if (v9fs_proto_dotl(v9ses)) 238 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 239 else 240 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 241 } 242 243 /** 244 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 245 * issuing a attribute request 246 * @v9ses: session information 247 * @fid: fid to issue attribute request for 248 * @sb: superblock on which to create inode 249 * 250 */ 251 static inline struct inode * 252 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 253 struct super_block *sb) 254 { 255 if (v9fs_proto_dotl(v9ses)) 256 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 257 else 258 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 259 } 260 261 #endif 262