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 }; 41 42 /* possible values of ->cache */ 43 /** 44 * enum p9_cache_modes - user specified cache preferences 45 * @CACHE_NONE: do not cache data, dentries, or directory contents (default) 46 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency 47 * 48 * eventually support loose, tight, time, session, default always none 49 */ 50 51 enum p9_cache_modes { 52 CACHE_NONE, 53 CACHE_MMAP, 54 CACHE_LOOSE, 55 CACHE_FSCACHE, 56 nr__p9_cache_modes 57 }; 58 59 /** 60 * struct v9fs_session_info - per-instance session information 61 * @flags: session options of type &p9_session_flags 62 * @nodev: set to 1 to disable device mapping 63 * @debug: debug level 64 * @afid: authentication handle 65 * @cache: cache mode of type &p9_cache_modes 66 * @cachetag: the tag of the cache associated with this session 67 * @fscache: session cookie associated with FS-Cache 68 * @uname: string user name to mount hierarchy as 69 * @aname: mount specifier for remote hierarchy 70 * @maxdata: maximum data to be sent/recvd per protocol message 71 * @dfltuid: default numeric userid to mount hierarchy as 72 * @dfltgid: default numeric groupid to mount hierarchy as 73 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy 74 * @clnt: reference to 9P network client instantiated for this session 75 * @slist: reference to list of registered 9p sessions 76 * 77 * This structure holds state for each session instance established during 78 * a sys_mount() . 79 * 80 * Bugs: there seems to be a lot of state which could be condensed and/or 81 * removed. 82 */ 83 84 struct v9fs_session_info { 85 /* options */ 86 unsigned char flags; 87 unsigned char nodev; 88 unsigned short debug; 89 unsigned int afid; 90 unsigned int cache; 91 #ifdef CONFIG_9P_FSCACHE 92 char *cachetag; 93 struct fscache_volume *fscache; 94 #endif 95 96 char *uname; /* user name to mount as */ 97 char *aname; /* name of remote hierarchy being mounted */ 98 unsigned int maxdata; /* max data for client interface */ 99 kuid_t dfltuid; /* default uid/muid for legacy support */ 100 kgid_t dfltgid; /* default gid for legacy support */ 101 kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */ 102 struct p9_client *clnt; /* 9p client */ 103 struct list_head slist; /* list of sessions registered with v9fs */ 104 struct rw_semaphore rename_sem; 105 long session_lock_timeout; /* retry interval for blocking locks */ 106 }; 107 108 /* cache_validity flags */ 109 #define V9FS_INO_INVALID_ATTR 0x01 110 111 struct v9fs_inode { 112 struct { 113 /* These must be contiguous */ 114 struct inode vfs_inode; /* the VFS's inode record */ 115 struct netfs_i_context netfs_ctx; /* Netfslib context */ 116 }; 117 struct p9_qid qid; 118 unsigned int cache_validity; 119 struct p9_fid *writeback_fid; 120 struct mutex v_mutex; 121 }; 122 123 static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 124 { 125 return container_of(inode, struct v9fs_inode, vfs_inode); 126 } 127 128 static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 129 { 130 #ifdef CONFIG_9P_FSCACHE 131 return netfs_i_cookie(&v9inode->vfs_inode); 132 #else 133 return NULL; 134 #endif 135 } 136 137 static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 138 { 139 #ifdef CONFIG_9P_FSCACHE 140 return v9ses->fscache; 141 #else 142 return NULL; 143 #endif 144 } 145 146 147 extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 148 149 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 150 const char *dev_name, char *data); 151 extern void v9fs_session_close(struct v9fs_session_info *v9ses); 152 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 153 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 154 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 155 unsigned int flags); 156 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 157 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 158 extern int v9fs_vfs_rename(struct user_namespace *mnt_userns, 159 struct inode *old_dir, struct dentry *old_dentry, 160 struct inode *new_dir, struct dentry *new_dentry, 161 unsigned int flags); 162 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 163 struct p9_fid *fid, 164 struct super_block *sb, int new); 165 extern const struct inode_operations v9fs_dir_inode_operations_dotl; 166 extern const struct inode_operations v9fs_file_inode_operations_dotl; 167 extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 168 extern const struct netfs_request_ops v9fs_req_ops; 169 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 170 struct p9_fid *fid, 171 struct super_block *sb, int new); 172 173 /* other default globals */ 174 #define V9FS_PORT 564 175 #define V9FS_DEFUSER "nobody" 176 #define V9FS_DEFANAME "" 177 #define V9FS_DEFUID KUIDT_INIT(-2) 178 #define V9FS_DEFGID KGIDT_INIT(-2) 179 180 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 181 { 182 return inode->i_sb->s_fs_info; 183 } 184 185 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 186 { 187 return dentry->d_sb->s_fs_info; 188 } 189 190 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 191 { 192 return v9ses->flags & V9FS_PROTO_2000U; 193 } 194 195 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 196 { 197 return v9ses->flags & V9FS_PROTO_2000L; 198 } 199 200 /** 201 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 202 * issuing a attribute request 203 * @v9ses: session information 204 * @fid: fid to issue attribute request for 205 * @sb: superblock on which to create inode 206 * 207 */ 208 static inline struct inode * 209 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 210 struct super_block *sb) 211 { 212 if (v9fs_proto_dotl(v9ses)) 213 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 214 else 215 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 216 } 217 218 /** 219 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 220 * issuing a attribute request 221 * @v9ses: session information 222 * @fid: fid to issue attribute request for 223 * @sb: superblock on which to create inode 224 * 225 */ 226 static inline struct inode * 227 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 228 struct super_block *sb) 229 { 230 if (v9fs_proto_dotl(v9ses)) 231 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 232 else 233 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 234 } 235 236 #endif 237