1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
|
/*
* include/net/9p/client.h
*
* 9P Client Definitions
*
* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#ifndef NET_9P_CLIENT_H
#define NET_9P_CLIENT_H
#include <linux/utsname.h>
/* Number of requests per row */
#define P9_ROW_MAXTAG 255
/** enum p9_proto_versions - 9P protocol versions
* @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u
* @p9_proto_2000u: 9P2000.u extension
* @p9_proto_2000L: 9P2000.L extension
*/
enum p9_proto_versions{
p9_proto_legacy,
p9_proto_2000u,
p9_proto_2000L,
};
/**
* enum p9_trans_status - different states of underlying transports
* @Connected: transport is connected and healthy
* @Disconnected: transport has been disconnected
* @Hung: transport is connected by wedged
*
* This enumeration details the various states a transport
* instatiation can be in.
*/
enum p9_trans_status {
Connected,
BeginDisconnect,
Disconnected,
Hung,
};
/**
* enum p9_req_status_t - status of a request
* @REQ_STATUS_IDLE: request slot unused
* @REQ_STATUS_ALLOC: request has been allocated but not sent
* @REQ_STATUS_UNSENT: request waiting to be sent
* @REQ_STATUS_SENT: request sent to server
* @REQ_STATUS_RCVD: response received from server
* @REQ_STATUS_FLSHD: request has been flushed
* @REQ_STATUS_ERROR: request encountered an error on the client side
*
* The @REQ_STATUS_IDLE state is used to mark a request slot as unused
* but use is actually tracked by the idpool structure which handles tag
* id allocation.
*
*/
enum p9_req_status_t {
REQ_STATUS_IDLE,
REQ_STATUS_ALLOC,
REQ_STATUS_UNSENT,
REQ_STATUS_SENT,
REQ_STATUS_RCVD,
REQ_STATUS_FLSHD,
REQ_STATUS_ERROR,
};
/**
* struct p9_req_t - request slots
* @status: status of this request slot
* @t_err: transport error
* @flush_tag: tag of request being flushed (for flush requests)
* @wq: wait_queue for the client to block on for this request
* @tc: the request fcall structure
* @rc: the response fcall structure
* @aux: transport specific data (provided for trans_fd migration)
* @req_list: link for higher level objects to chain requests
*
* Transport use an array to track outstanding requests
* instead of a list. While this may incurr overhead during initial
* allocation or expansion, it makes request lookup much easier as the
* tag id is a index into an array. (We use tag+1 so that we can accommodate
* the -1 tag for the T_VERSION request).
* This also has the nice effect of only having to allocate wait_queues
* once, instead of constantly allocating and freeing them. Its possible
* other resources could benefit from this scheme as well.
*
*/
struct p9_req_t {
int status;
int t_err;
wait_queue_head_t *wq;
struct p9_fcall *tc;
struct p9_fcall *rc;
void *aux;
struct list_head req_list;
};
/**
* struct p9_client - per client instance state
* @lock: protect @fidlist
* @msize: maximum data size negotiated by protocol
* @dotu: extension flags negotiated by protocol
* @proto_version: 9P protocol version to use
* @trans_mod: module API instantiated with this client
* @trans: tranport instance state and API
* @fidpool: fid handle accounting for session
* @fidlist: List of active fid handles
* @tagpool - transaction id accounting for session
* @reqs - 2D array of requests
* @max_tag - current maximum tag id allocated
* @name - node name used as client id
*
* The client structure is used to keep track of various per-client
* state that has been instantiated.
* In order to minimize per-transaction overhead we use a
* simple array to lookup requests instead of a hash table
* or linked list. In order to support larger number of
* transactions, we make this a 2D array, allocating new rows
* when we need to grow the total number of the transactions.
*
* Each row is 256 requests and we'll support up to 256 rows for
* a total of 64k concurrent requests per session.
*
* Bugs: duplicated data and potentially unnecessary elements.
*/
struct p9_client {
spinlock_t lock; /* protect client structure */
unsigned int msize;
unsigned char proto_version;
struct p9_trans_module *trans_mod;
enum p9_trans_status status;
void *trans;
struct p9_idpool *fidpool;
struct list_head fidlist;
struct p9_idpool *tagpool;
struct p9_req_t *reqs[P9_ROW_MAXTAG];
int max_tag;
char name[__NEW_UTS_LEN + 1];
};
/**
* struct p9_fid - file system entity handle
* @clnt: back pointer to instantiating &p9_client
* @fid: numeric identifier for this handle
* @mode: current mode of this fid (enum?)
* @qid: the &p9_qid server identifier this handle points to
* @iounit: the server reported maximum transaction size for this file
* @uid: the numeric uid of the local user who owns this handle
* @rdir: readdir accounting structure (allocated on demand)
* @flist: per-client-instance fid tracking
* @dlist: per-dentry fid tracking
*
* TODO: This needs lots of explanation.
*/
struct p9_fid {
struct p9_client *clnt;
u32 fid;
int mode;
struct p9_qid qid;
u32 iounit;
kuid_t uid;
void *rdir;
struct list_head flist;
struct hlist_node dlist; /* list of all fids attached to a dentry */
};
/**
* struct p9_dirent - directory entry structure
* @qid: The p9 server qid for this dirent
* @d_off: offset to the next dirent
* @d_type: type of file
* @d_name: file name
*/
struct p9_dirent {
struct p9_qid qid;
u64 d_off;
unsigned char d_type;
char d_name[256];
};
struct iov_iter;
int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb);
int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid,
const char *name);
int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
struct p9_fid *newdirfid, const char *new_name);
struct p9_client *p9_client_create(const char *dev_name, char *options);
void p9_client_destroy(struct p9_client *clnt);
void p9_client_disconnect(struct p9_client *clnt);
void p9_client_begin_disconnect(struct p9_client *clnt);
struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
char *uname, kuid_t n_uname, char *aname);
struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
char **wnames, int clone);
int p9_client_open(struct p9_fid *fid, int mode);
int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
char *extension);
int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname);
int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, kgid_t gid,
struct p9_qid *qid);
int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
kgid_t gid, struct p9_qid *qid);
int p9_client_clunk(struct p9_fid *fid);
int p9_client_fsync(struct p9_fid *fid, int datasync);
int p9_client_remove(struct p9_fid *fid);
int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags);
int p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err);
int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err);
int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset);
int p9dirent_read(struct p9_client *clnt, char *buf, int len,
struct p9_dirent *dirent);
struct p9_wstat *p9_client_stat(struct p9_fid *fid);
int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr);
struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
u64 request_mask);
int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode,
dev_t rdev, kgid_t gid, struct p9_qid *);
int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
kgid_t gid, struct p9_qid *);
int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status);
int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *);
void p9stat_free(struct p9_wstat *);
int p9_is_proto_dotu(struct p9_client *clnt);
int p9_is_proto_dotl(struct p9_client *clnt);
struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *);
int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int);
int p9_client_readlink(struct p9_fid *fid, char **target);
#endif /* NET_9P_CLIENT_H */
|
