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 /** 47 * enum p9_cache_shortcuts - human readable cache preferences 48 * @CACHE_SC_NONE: disable all caches 49 * @CACHE_SC_READAHEAD: only provide caching for readahead 50 * @CACHE_SC_MMAP: provide caching to enable mmap 51 * @CACHE_SC_LOOSE: non-coherent caching for files and meta data 52 * @CACHE_SC_FSCACHE: persistent non-coherent caching for files and meta-data 53 * 54 */ 55 56 enum p9_cache_shortcuts { 57 CACHE_SC_NONE = 0b00000000, 58 CACHE_SC_READAHEAD = 0b00000001, 59 CACHE_SC_MMAP = 0b00000101, 60 CACHE_SC_LOOSE = 0b00001111, 61 CACHE_SC_FSCACHE = 0b10001111, 62 }; 63 64 /** 65 * enum p9_cache_bits - possible values of ->cache 66 * @CACHE_NONE: caches disabled 67 * @CACHE_FILE: file caching (open to close) 68 * @CACHE_META: meta-data and directory caching 69 * @CACHE_WRITEBACK: write-back caching for files 70 * @CACHE_LOOSE: don't check cache consistency 71 * @CACHE_FSCACHE: local persistent caches 72 * 73 */ 74 75 enum p9_cache_bits { 76 CACHE_NONE = 0b00000000, 77 CACHE_FILE = 0b00000001, 78 CACHE_META = 0b00000010, 79 CACHE_WRITEBACK = 0b00000100, 80 CACHE_LOOSE = 0b00001000, 81 CACHE_FSCACHE = 0b10000000, 82 }; 83 84 /** 85 * struct v9fs_session_info - per-instance session information 86 * @flags: session options of type &p9_session_flags 87 * @nodev: set to 1 to disable device mapping 88 * @debug: debug level 89 * @afid: authentication handle 90 * @cache: cache mode of type &p9_cache_bits 91 * @cachetag: the tag of the cache associated with this session 92 * @fscache: session cookie associated with FS-Cache 93 * @uname: string user name to mount hierarchy as 94 * @aname: mount specifier for remote hierarchy 95 * @maxdata: maximum data to be sent/recvd per protocol message 96 * @dfltuid: default numeric userid to mount hierarchy as 97 * @dfltgid: default numeric groupid to mount hierarchy as 98 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 99 * @clnt: reference to 9P network client instantiated for this session 100 * @slist: reference to list of registered 9p sessions 101 * 102 * This structure holds state for each session instance established during 103 * a sys_mount() . 104 * 105 * Bugs: there seems to be a lot of state which could be condensed and/or 106 * removed. 107 */ 108 109 struct v9fs_session_info { 110 /* options */ 111 unsigned int flags; 112 unsigned char nodev; 113 unsigned short debug; 114 unsigned int afid; 115 unsigned int cache; 116 #ifdef CONFIG_9P_FSCACHE 117 char *cachetag; 118 struct fscache_volume *fscache; 119 #endif 120 121 char *uname; /* user name to mount as */ 122 char *aname; /* name of remote hierarchy being mounted */ 123 unsigned int maxdata; /* max data for client interface */ 124 kuid_t dfltuid; /* default uid/muid for legacy support */ 125 kgid_t dfltgid; /* default gid for legacy support */ 126 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 127 struct p9_client *clnt; /* 9p client */ 128 struct list_head slist; /* list of sessions registered with v9fs */ 129 struct rw_semaphore rename_sem; 130 long session_lock_timeout; /* retry interval for blocking locks */ 131 }; 132 133 /* cache_validity flags */ 134 #define V9FS_INO_INVALID_ATTR 0x01 135 136 struct v9fs_inode { 137 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 138 struct p9_qid qid; 139 unsigned int cache_validity; 140 struct mutex v_mutex; 141 }; 142 143 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 144 { 145 return container_of(inode, struct v9fs_inode, netfs.inode); 146 } 147 148 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 149 { 150 #ifdef CONFIG_9P_FSCACHE 151 return netfs_i_cookie(&v9inode->netfs); 152 #else 153 return NULL; 154 #endif 155 } 156 157 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 158 { 159 #ifdef CONFIG_9P_FSCACHE 160 return v9ses->fscache; 161 #else 162 return NULL; 163 #endif 164 } 165 166 167 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 168 169 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 170 const char *dev_name, char *data); 171 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 172 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 173 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 174 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 175 unsigned int flags); 176 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 177 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 178 extern int v9fs_vfs_rename(struct mnt_idmap *idmap, 179 struct inode *old_dir, struct dentry *old_dentry, 180 struct inode *new_dir, struct dentry *new_dentry, 181 unsigned int flags); 182 extern struct inode *v9fs_fid_iget(struct super_block *sb, struct p9_fid *fid); 183 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 184 extern const struct inode_operations v9fs_file_inode_operations_dotl; 185 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 186 extern const struct netfs_request_ops v9fs_req_ops; 187 extern struct inode *v9fs_fid_iget_dotl(struct super_block *sb, 188 struct p9_fid *fid); 189 190 /* other default globals */ 191 #define V9FS_PORT 564 192 #define V9FS_DEFUSER "nobody" 193 #define V9FS_DEFANAME "" 194 #define V9FS_DEFUID KUIDT_INIT(-2) 195 #define V9FS_DEFGID KGIDT_INIT(-2) 196 197 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 198 { 199 return inode->i_sb->s_fs_info; 200 } 201 202 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 203 { 204 return dentry->d_sb->s_fs_info; 205 } 206 207 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 208 { 209 return v9ses->flags & V9FS_PROTO_2000U; 210 } 211 212 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 213 { 214 return v9ses->flags & V9FS_PROTO_2000L; 215 } 216 217 /** 218 * v9fs_get_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_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_fid_iget_dotl(sb, fid); 231 else 232 return v9fs_fid_iget(sb, fid); 233 } 234 235 #endif 236