v9fs.h (7376B)
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 33enum 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 51enum 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 84struct 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 111struct v9fs_inode { 112 struct netfs_inode netfs; /* Netfslib context and vfs inode */ 113 struct p9_qid qid; 114 unsigned int cache_validity; 115 struct p9_fid *writeback_fid; 116 struct mutex v_mutex; 117}; 118 119static inline struct v9fs_inode *V9FS_I(const struct inode *inode) 120{ 121 return container_of(inode, struct v9fs_inode, netfs.inode); 122} 123 124static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode) 125{ 126#ifdef CONFIG_9P_FSCACHE 127 return netfs_i_cookie(&v9inode->netfs); 128#else 129 return NULL; 130#endif 131} 132 133static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses) 134{ 135#ifdef CONFIG_9P_FSCACHE 136 return v9ses->fscache; 137#else 138 return NULL; 139#endif 140} 141 142 143extern int v9fs_show_options(struct seq_file *m, struct dentry *root); 144 145struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, 146 const char *dev_name, char *data); 147extern void v9fs_session_close(struct v9fs_session_info *v9ses); 148extern void v9fs_session_cancel(struct v9fs_session_info *v9ses); 149extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses); 150extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 151 unsigned int flags); 152extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); 153extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); 154extern int v9fs_vfs_rename(struct user_namespace *mnt_userns, 155 struct inode *old_dir, struct dentry *old_dentry, 156 struct inode *new_dir, struct dentry *new_dentry, 157 unsigned int flags); 158extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, 159 struct p9_fid *fid, 160 struct super_block *sb, int new); 161extern const struct inode_operations v9fs_dir_inode_operations_dotl; 162extern const struct inode_operations v9fs_file_inode_operations_dotl; 163extern const struct inode_operations v9fs_symlink_inode_operations_dotl; 164extern const struct netfs_request_ops v9fs_req_ops; 165extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, 166 struct p9_fid *fid, 167 struct super_block *sb, int new); 168 169/* other default globals */ 170#define V9FS_PORT 564 171#define V9FS_DEFUSER "nobody" 172#define V9FS_DEFANAME "" 173#define V9FS_DEFUID KUIDT_INIT(-2) 174#define V9FS_DEFGID KGIDT_INIT(-2) 175 176static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) 177{ 178 return inode->i_sb->s_fs_info; 179} 180 181static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry) 182{ 183 return dentry->d_sb->s_fs_info; 184} 185 186static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) 187{ 188 return v9ses->flags & V9FS_PROTO_2000U; 189} 190 191static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) 192{ 193 return v9ses->flags & V9FS_PROTO_2000L; 194} 195 196/** 197 * v9fs_get_inode_from_fid - Helper routine to populate an inode by 198 * issuing a attribute request 199 * @v9ses: session information 200 * @fid: fid to issue attribute request for 201 * @sb: superblock on which to create inode 202 * 203 */ 204static inline struct inode * 205v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 206 struct super_block *sb) 207{ 208 if (v9fs_proto_dotl(v9ses)) 209 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0); 210 else 211 return v9fs_inode_from_fid(v9ses, fid, sb, 0); 212} 213 214/** 215 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by 216 * issuing a attribute request 217 * @v9ses: session information 218 * @fid: fid to issue attribute request for 219 * @sb: superblock on which to create inode 220 * 221 */ 222static inline struct inode * 223v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 224 struct super_block *sb) 225{ 226 if (v9fs_proto_dotl(v9ses)) 227 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1); 228 else 229 return v9fs_inode_from_fid(v9ses, fid, sb, 1); 230} 231 232#endif