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 * @V9FS_NDENTRY_TIMEOUT_SET: Has negative dentry timeout retention time been 28 * overridden by negtimeout mount option 29 * 30 * Session flags reflect options selected by users at mount time 31 */ 32 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \ 33 V9FS_ACCESS_USER | \ 34 V9FS_ACCESS_CLIENT) 35 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY 36 #define V9FS_ACL_MASK V9FS_POSIX_ACL 37 38 enum p9_session_flags { 39 V9FS_PROTO_2000U = 0x01, 40 V9FS_PROTO_2000L = 0x02, 41 V9FS_ACCESS_SINGLE = 0x04, 42 V9FS_ACCESS_USER = 0x08, 43 V9FS_ACCESS_CLIENT = 0x10, 44 V9FS_POSIX_ACL = 0x20, 45 V9FS_NO_XATTR = 0x40, 46 V9FS_IGNORE_QV = 0x80, /* ignore qid.version for cache hints */ 47 V9FS_DIRECT_IO = 0x100, 48 V9FS_SYNC = 0x200, 49 V9FS_NDENTRY_TIMEOUT_SET = 0x400, 50 }; 51 52 /** 53 * enum p9_cache_shortcuts - human readable cache preferences 54 * @CACHE_SC_NONE: disable all caches 55 * @CACHE_SC_READAHEAD: only provide caching for readahead 56 * @CACHE_SC_MMAP: provide caching to enable mmap 57 * @CACHE_SC_LOOSE: non-coherent caching for files and meta data 58 * @CACHE_SC_FSCACHE: persistent non-coherent caching for files and meta-data 59 * 60 */ 61 62 enum p9_cache_shortcuts { 63 CACHE_SC_NONE = 0b00000000, 64 CACHE_SC_READAHEAD = 0b00000001, 65 CACHE_SC_MMAP = 0b00000101, 66 CACHE_SC_LOOSE = 0b00001111, 67 CACHE_SC_FSCACHE = 0b10001111, 68 }; 69 70 /** 71 * enum p9_cache_bits - possible values of ->cache 72 * @CACHE_NONE: caches disabled 73 * @CACHE_FILE: file caching (open to close) 74 * @CACHE_META: meta-data and directory caching 75 * @CACHE_WRITEBACK: write-back caching for files 76 * @CACHE_LOOSE: don't check cache consistency 77 * @CACHE_FSCACHE: local persistent caches 78 * 79 */ 80 81 enum p9_cache_bits { 82 CACHE_NONE = 0b00000000, 83 CACHE_FILE = 0b00000001, 84 CACHE_META = 0b00000010, 85 CACHE_WRITEBACK = 0b00000100, 86 CACHE_LOOSE = 0b00001000, 87 CACHE_FSCACHE = 0b10000000, 88 }; 89 90 /** 91 * struct v9fs_session_info - per-instance session information 92 * @flags: session options of type &p9_session_flags 93 * @nodev: set to 1 to disable device mapping 94 * @debug: debug level 95 * @afid: authentication handle 96 * @cache: cache mode of type &p9_cache_bits 97 * @ndentry_timeout: Negative dentry lookup cache retention time in ms 98 * @cachetag: the tag of the cache associated with this session 99 * @fscache: session cookie associated with FS-Cache 100 * @uname: string user name to mount hierarchy as 101 * @aname: mount specifier for remote hierarchy 102 * @maxdata: maximum data to be sent/recvd per protocol message 103 * @dfltuid: default numeric userid to mount hierarchy as 104 * @dfltgid: default numeric groupid to mount hierarchy as 105 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 106 * @clnt: reference to 9P network client instantiated for this session 107 * @slist: reference to list of registered 9p sessions 108 * @ndentry_timeout_ms: Negative dentry caching retention time 109 * 110 * This structure holds state for each session instance established during 111 * a sys_mount() . 112 * 113 * Bugs: there seems to be a lot of state which could be condensed and/or 114 * removed. 115 */ 116 117 struct v9fs_session_info { 118 /* options */ 119 unsigned int flags; 120 unsigned char nodev; 121 unsigned short debug; 122 unsigned int afid; 123 unsigned int cache; 124 unsigned int ndentry_timeout_ms; 125 #ifdef CONFIG_9P_FSCACHE 126 char *cachetag; 127 struct fscache_volume *fscache; 128 #endif 129 130 char *uname; /* user name to mount as */ 131 char *aname; /* name of remote hierarchy being mounted */ 132 unsigned int maxdata; /* max data for client interface */ 133 kuid_t dfltuid; /* default uid/muid for legacy support */ 134 kgid_t dfltgid; /* default gid for legacy support */ 135 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 136 struct p9_client *clnt; /* 9p client */ 137 struct list_head slist; /* list of sessions registered with v9fs */ 138 struct rw_semaphore rename_sem; 139 long session_lock_timeout; /* retry interval for blocking locks */ 140 }; 141 142 #define NDENTRY_TIMEOUT_NEVER (-1U) 143 144 /* cache_validity flags */ 145 #define V9FS_INO_INVALID_ATTR 0x01 146 147 struct v9fs_inode { 148 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 149 struct p9_qid qid; 150 unsigned int cache_validity; 151 struct mutex v_mutex; 152 }; 153 154 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 155 { 156 return container_of(inode, struct v9fs_inode, netfs.inode); 157 } 158 159 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 160 { 161 #ifdef CONFIG_9P_FSCACHE 162 return netfs_i_cookie(&v9inode->netfs); 163 #else 164 return NULL; 165 #endif 166 } 167 168 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 169 { 170 #ifdef CONFIG_9P_FSCACHE 171 return v9ses->fscache; 172 #else 173 return NULL; 174 #endif 175 } 176 177 extern const struct fs_parameter_spec v9fs_param_spec[]; 178 179 extern int v9fs_parse_param(struct fs_context *fc, struct fs_parameter *param); 180 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 181 182 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 183 struct fs_context *fc); 184 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 185 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 186 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 187 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 188 unsigned int flags); 189 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 190 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 191 extern int v9fs_vfs_rename(struct mnt_idmap *idmap, 192 struct inode *old_dir, struct dentry *old_dentry, 193 struct inode *new_dir, struct dentry *new_dentry, 194 unsigned int flags); 195 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 196 struct p9_fid *fid, 197 struct super_block *sb, int new); 198 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 199 extern const struct inode_operations v9fs_file_inode_operations_dotl; 200 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 201 extern const struct netfs_request_ops v9fs_req_ops; 202 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 203 struct p9_fid *fid, 204 struct super_block *sb, int new); 205 206 /* other default globals */ 207 #define V9FS_PORT 564 208 #define V9FS_DEFUSER "nobody" 209 #define V9FS_DEFANAME "" 210 #define V9FS_DEFUID KUIDT_INIT(-2) 211 #define V9FS_DEFGID KGIDT_INIT(-2) 212 213 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 214 { 215 return inode->i_sb->s_fs_info; 216 } 217 218 static inline struct v9fs_session_info *v9fs_dentry2v9ses(const struct dentry *dentry) 219 { 220 return dentry->d_sb->s_fs_info; 221 } 222 223 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 224 { 225 return v9ses->flags & V9FS_PROTO_2000U; 226 } 227 228 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 229 { 230 return v9ses->flags & V9FS_PROTO_2000L; 231 } 232 233 /** 234 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 235 * issuing a attribute request 236 * @v9ses: session information 237 * @fid: fid to issue attribute request for 238 * @sb: superblock on which to create inode 239 * 240 */ 241 static inline struct inode * 242 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 243 struct super_block *sb) 244 { 245 if (v9fs_proto_dotl(v9ses)) 246 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 247 else 248 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 249 } 250 251 /** 252 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 253 * issuing a attribute request 254 * @v9ses: session information 255 * @fid: fid to issue attribute request for 256 * @sb: superblock on which to create inode 257 * 258 */ 259 static inline struct inode * 260 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 261 struct super_block *sb) 262 { 263 if (v9fs_proto_dotl(v9ses)) 264 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 265 else 266 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 267 } 268 269 #endif 270