1 /*
2 * V9FS definitions.
3 *
4 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
5 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2
9 * as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to:
18 * Free Software Foundation
19 * 51 Franklin Street, Fifth Floor
20 * Boston, MA 02111-1301 USA
21 *
22 */
23 #ifndef FS_9P_V9FS_H
24 #define FS_9P_V9FS_H
25
26 #include <linux/backing-dev.h>
27
28 /**
29 * enum p9_session_flags - option flags for each 9P session
30 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
31 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
32 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
33 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
34 * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
35 * @V9FS_ACCESS_ANY: use a single attach for all users
36 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
37 * @V9FS_POSIX_ACL: POSIX ACLs are enforced
38 *
39 * Session flags reflect options selected by users at mount time
40 */
41 #define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \
42 V9FS_ACCESS_USER | \
43 V9FS_ACCESS_CLIENT)
44 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
45 #define V9FS_ACL_MASK V9FS_POSIX_ACL
46
47 enum p9_session_flags {
48 V9FS_PROTO_2000U = 0x01,
49 V9FS_PROTO_2000L = 0x02,
50 V9FS_ACCESS_SINGLE = 0x04,
51 V9FS_ACCESS_USER = 0x08,
52 V9FS_ACCESS_CLIENT = 0x10,
53 V9FS_POSIX_ACL = 0x20
54 };
55
56 /* possible values of ->cache */
57 /**
58 * enum p9_cache_modes - user specified cache preferences
59 * @CACHE_NONE: do not cache data, dentries, or directory contents (default)
60 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
61 *
62 * eventually support loose, tight, time, session, default always none
63 */
64
65 enum p9_cache_modes {
66 CACHE_NONE,
67 CACHE_LOOSE,
68 CACHE_FSCACHE,
69 };
70
71 /**
72 * struct v9fs_session_info - per-instance session information
73 * @flags: session options of type &p9_session_flags
74 * @nodev: set to 1 to disable device mapping
75 * @debug: debug level
76 * @afid: authentication handle
77 * @cache: cache mode of type &p9_cache_modes
78 * @cachetag: the tag of the cache associated with this session
79 * @fscache: session cookie associated with FS-Cache
80 * @options: copy of options string given by user
81 * @uname: string user name to mount hierarchy as
82 * @aname: mount specifier for remote hierarchy
83 * @maxdata: maximum data to be sent/recvd per protocol message
84 * @dfltuid: default numeric userid to mount hierarchy as
85 * @dfltgid: default numeric groupid to mount hierarchy as
86 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
87 * @clnt: reference to 9P network client instantiated for this session
88 * @slist: reference to list of registered 9p sessions
89 *
90 * This structure holds state for each session instance established during
91 * a sys_mount() .
92 *
93 * Bugs: there seems to be a lot of state which could be condensed and/or
94 * removed.
95 */
96
97 struct v9fs_session_info {
98 /* options */
99 unsigned char flags;
100 unsigned char nodev;
101 unsigned short debug;
102 unsigned int afid;
103 unsigned int cache;
104 #ifdef CONFIG_9P_FSCACHE
105 char *cachetag;
106 struct fscache_cookie *fscache;
107 #endif
108
109 char *uname; /* user name to mount as */
110 char *aname; /* name of remote hierarchy being mounted */
111 unsigned int maxdata; /* max data for client interface */
112 unsigned int dfltuid; /* default uid/muid for legacy support */
113 unsigned int dfltgid; /* default gid for legacy support */
114 u32 uid; /* if ACCESS_SINGLE, the uid that has access */
115 struct p9_client *clnt; /* 9p client */
116 struct list_head slist; /* list of sessions registered with v9fs */
117 struct backing_dev_info bdi;
118 struct rw_semaphore rename_sem;
119 };
120
121 /* cache_validity flags */
122 #define V9FS_INO_INVALID_ATTR 0x01
123
124 struct v9fs_inode {
125 #ifdef CONFIG_9P_FSCACHE
126 spinlock_t fscache_lock;
127 struct fscache_cookie *fscache;
128 #endif
129 struct p9_qid qid;
130 unsigned int cache_validity;
131 struct p9_fid *writeback_fid;
132 struct mutex v_mutex;
133 struct inode vfs_inode;
134 };
135
V9FS_I(const struct inode * inode)136 static inline struct v9fs_inode *V9FS_I(const struct inode *inode)
137 {
138 return container_of(inode, struct v9fs_inode, vfs_inode);
139 }
140
141 struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
142 char *);
143 extern void v9fs_session_close(struct v9fs_session_info *v9ses);
144 extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
145 extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
146 extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
147 struct nameidata *nameidata);
148 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
149 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
150 extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
151 struct inode *new_dir, struct dentry *new_dentry);
152 extern void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd,
153 void *p);
154 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
155 struct p9_fid *fid,
156 struct super_block *sb, int new);
157 extern const struct inode_operations v9fs_dir_inode_operations_dotl;
158 extern const struct inode_operations v9fs_file_inode_operations_dotl;
159 extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
160 extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
161 struct p9_fid *fid,
162 struct super_block *sb, int new);
163
164 /* other default globals */
165 #define V9FS_PORT 564
166 #define V9FS_DEFUSER "nobody"
167 #define V9FS_DEFANAME ""
168 #define V9FS_DEFUID (-2)
169 #define V9FS_DEFGID (-2)
170
v9fs_inode2v9ses(struct inode * inode)171 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
172 {
173 return (inode->i_sb->s_fs_info);
174 }
175
v9fs_dentry2v9ses(struct dentry * dentry)176 static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
177 {
178 return dentry->d_sb->s_fs_info;
179 }
180
v9fs_proto_dotu(struct v9fs_session_info * v9ses)181 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
182 {
183 return v9ses->flags & V9FS_PROTO_2000U;
184 }
185
v9fs_proto_dotl(struct v9fs_session_info * v9ses)186 static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
187 {
188 return v9ses->flags & V9FS_PROTO_2000L;
189 }
190
191 /**
192 * v9fs_get_inode_from_fid - Helper routine to populate an inode by
193 * issuing a attribute request
194 * @v9ses: session information
195 * @fid: fid to issue attribute request for
196 * @sb: superblock on which to create inode
197 *
198 */
199 static inline struct inode *
v9fs_get_inode_from_fid(struct v9fs_session_info * v9ses,struct p9_fid * fid,struct super_block * sb)200 v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
201 struct super_block *sb)
202 {
203 if (v9fs_proto_dotl(v9ses))
204 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
205 else
206 return v9fs_inode_from_fid(v9ses, fid, sb, 0);
207 }
208
209 /**
210 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
211 * issuing a attribute request
212 * @v9ses: session information
213 * @fid: fid to issue attribute request for
214 * @sb: superblock on which to create inode
215 *
216 */
217 static inline struct inode *
v9fs_get_new_inode_from_fid(struct v9fs_session_info * v9ses,struct p9_fid * fid,struct super_block * sb)218 v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
219 struct super_block *sb)
220 {
221 if (v9fs_proto_dotl(v9ses))
222 return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
223 else
224 return v9fs_inode_from_fid(v9ses, fid, sb, 1);
225 }
226
227 #endif
228