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1/*
2 * include/net/9p/client.h
3 *
4 * 9P Client Definitions
5 *
6 * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to:
20 * Free Software Foundation
21 * 51 Franklin Street, Fifth Floor
22 * Boston, MA 02111-1301 USA
23 *
24 */
25
26#ifndef NET_9P_CLIENT_H
27#define NET_9P_CLIENT_H
28
29#include <linux/utsname.h>
30
31/* Number of requests per row */
32#define P9_ROW_MAXTAG 255
33
34/** enum p9_proto_versions - 9P protocol versions
35 * @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u
36 * @p9_proto_2000u: 9P2000.u extension
37 * @p9_proto_2000L: 9P2000.L extension
38 */
39
40enum p9_proto_versions{
41 p9_proto_legacy,
42 p9_proto_2000u,
43 p9_proto_2000L,
44};
45
46
47/**
48 * enum p9_trans_status - different states of underlying transports
49 * @Connected: transport is connected and healthy
50 * @Disconnected: transport has been disconnected
51 * @Hung: transport is connected by wedged
52 *
53 * This enumeration details the various states a transport
54 * instatiation can be in.
55 */
56
57enum p9_trans_status {
58 Connected,
59 BeginDisconnect,
60 Disconnected,
61 Hung,
62};
63
64/**
65 * enum p9_req_status_t - status of a request
66 * @REQ_STATUS_IDLE: request slot unused
67 * @REQ_STATUS_ALLOC: request has been allocated but not sent
68 * @REQ_STATUS_UNSENT: request waiting to be sent
69 * @REQ_STATUS_SENT: request sent to server
70 * @REQ_STATUS_RCVD: response received from server
71 * @REQ_STATUS_FLSHD: request has been flushed
72 * @REQ_STATUS_ERROR: request encountered an error on the client side
73 *
74 * The @REQ_STATUS_IDLE state is used to mark a request slot as unused
75 * but use is actually tracked by the idpool structure which handles tag
76 * id allocation.
77 *
78 */
79
80enum p9_req_status_t {
81 REQ_STATUS_IDLE,
82 REQ_STATUS_ALLOC,
83 REQ_STATUS_UNSENT,
84 REQ_STATUS_SENT,
85 REQ_STATUS_RCVD,
86 REQ_STATUS_FLSHD,
87 REQ_STATUS_ERROR,
88};
89
90/**
91 * struct p9_req_t - request slots
92 * @status: status of this request slot
93 * @t_err: transport error
94 * @flush_tag: tag of request being flushed (for flush requests)
95 * @wq: wait_queue for the client to block on for this request
96 * @tc: the request fcall structure
97 * @rc: the response fcall structure
98 * @aux: transport specific data (provided for trans_fd migration)
99 * @req_list: link for higher level objects to chain requests
100 *
101 * Transport use an array to track outstanding requests
102 * instead of a list. While this may incurr overhead during initial
103 * allocation or expansion, it makes request lookup much easier as the
104 * tag id is a index into an array. (We use tag+1 so that we can accommodate
105 * the -1 tag for the T_VERSION request).
106 * This also has the nice effect of only having to allocate wait_queues
107 * once, instead of constantly allocating and freeing them. Its possible
108 * other resources could benefit from this scheme as well.
109 *
110 */
111
112struct p9_req_t {
113 int status;
114 int t_err;
115 wait_queue_head_t *wq;
116 struct p9_fcall *tc;
117 struct p9_fcall *rc;
118 void *aux;
119
120 struct list_head req_list;
121};
122
123/**
124 * struct p9_client - per client instance state
125 * @lock: protect @fidlist
126 * @msize: maximum data size negotiated by protocol
127 * @dotu: extension flags negotiated by protocol
128 * @proto_version: 9P protocol version to use
129 * @trans_mod: module API instantiated with this client
130 * @trans: tranport instance state and API
131 * @fidpool: fid handle accounting for session
132 * @fidlist: List of active fid handles
133 * @tagpool - transaction id accounting for session
134 * @reqs - 2D array of requests
135 * @max_tag - current maximum tag id allocated
136 * @name - node name used as client id
137 *
138 * The client structure is used to keep track of various per-client
139 * state that has been instantiated.
140 * In order to minimize per-transaction overhead we use a
141 * simple array to lookup requests instead of a hash table
142 * or linked list. In order to support larger number of
143 * transactions, we make this a 2D array, allocating new rows
144 * when we need to grow the total number of the transactions.
145 *
146 * Each row is 256 requests and we'll support up to 256 rows for
147 * a total of 64k concurrent requests per session.
148 *
149 * Bugs: duplicated data and potentially unnecessary elements.
150 */
151
152struct p9_client {
153 spinlock_t lock; /* protect client structure */
154 unsigned int msize;
155 unsigned char proto_version;
156 struct p9_trans_module *trans_mod;
157 enum p9_trans_status status;
158 void *trans;
159
160 struct p9_idpool *fidpool;
161 struct list_head fidlist;
162
163 struct p9_idpool *tagpool;
164 struct p9_req_t *reqs[P9_ROW_MAXTAG];
165 int max_tag;
166
167 char name[__NEW_UTS_LEN + 1];
168};
169
170/**
171 * struct p9_fid - file system entity handle
172 * @clnt: back pointer to instantiating &p9_client
173 * @fid: numeric identifier for this handle
174 * @mode: current mode of this fid (enum?)
175 * @qid: the &p9_qid server identifier this handle points to
176 * @iounit: the server reported maximum transaction size for this file
177 * @uid: the numeric uid of the local user who owns this handle
178 * @rdir: readdir accounting structure (allocated on demand)
179 * @flist: per-client-instance fid tracking
180 * @dlist: per-dentry fid tracking
181 *
182 * TODO: This needs lots of explanation.
183 */
184
185struct p9_fid {
186 struct p9_client *clnt;
187 u32 fid;
188 int mode;
189 struct p9_qid qid;
190 u32 iounit;
191 kuid_t uid;
192
193 void *rdir;
194
195 struct list_head flist;
196 struct hlist_node dlist; /* list of all fids attached to a dentry */
197};
198
199/**
200 * struct p9_dirent - directory entry structure
201 * @qid: The p9 server qid for this dirent
202 * @d_off: offset to the next dirent
203 * @d_type: type of file
204 * @d_name: file name
205 */
206
207struct p9_dirent {
208 struct p9_qid qid;
209 u64 d_off;
210 unsigned char d_type;
211 char d_name[256];
212};
213
214struct iov_iter;
215
216int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb);
217int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid,
218 const char *name);
219int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
220 struct p9_fid *newdirfid, const char *new_name);
221struct p9_client *p9_client_create(const char *dev_name, char *options);
222void p9_client_destroy(struct p9_client *clnt);
223void p9_client_disconnect(struct p9_client *clnt);
224void p9_client_begin_disconnect(struct p9_client *clnt);
225struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
226 char *uname, kuid_t n_uname, char *aname);
227struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
228 char **wnames, int clone);
229int p9_client_open(struct p9_fid *fid, int mode);
230int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
231 char *extension);
232int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname);
233int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, kgid_t gid,
234 struct p9_qid *qid);
235int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
236 kgid_t gid, struct p9_qid *qid);
237int p9_client_clunk(struct p9_fid *fid);
238int p9_client_fsync(struct p9_fid *fid, int datasync);
239int p9_client_remove(struct p9_fid *fid);
240int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags);
241int p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err);
242int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err);
243int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset);
244int p9dirent_read(struct p9_client *clnt, char *buf, int len,
245 struct p9_dirent *dirent);
246struct p9_wstat *p9_client_stat(struct p9_fid *fid);
247int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
248int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr);
249
250struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
251 u64 request_mask);
252
253int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode,
254 dev_t rdev, kgid_t gid, struct p9_qid *);
255int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
256 kgid_t gid, struct p9_qid *);
257int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
258int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
259struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
260void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status);
261
262int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
263int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *);
264void p9stat_free(struct p9_wstat *);
265
266int p9_is_proto_dotu(struct p9_client *clnt);
267int p9_is_proto_dotl(struct p9_client *clnt);
268struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *);
269int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int);
270int p9_client_readlink(struct p9_fid *fid, char **target);
271
272#endif /* NET_9P_CLIENT_H */
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * include/net/9p/client.h
4 *
5 * 9P Client Definitions
6 *
7 * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
8 * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
9 */
10
11#ifndef NET_9P_CLIENT_H
12#define NET_9P_CLIENT_H
13
14#include <linux/utsname.h>
15#include <linux/idr.h>
16
17/* Number of requests per row */
18#define P9_ROW_MAXTAG 255
19
20/** enum p9_proto_versions - 9P protocol versions
21 * @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u
22 * @p9_proto_2000u: 9P2000.u extension
23 * @p9_proto_2000L: 9P2000.L extension
24 */
25
26enum p9_proto_versions{
27 p9_proto_legacy,
28 p9_proto_2000u,
29 p9_proto_2000L,
30};
31
32
33/**
34 * enum p9_trans_status - different states of underlying transports
35 * @Connected: transport is connected and healthy
36 * @Disconnected: transport has been disconnected
37 * @Hung: transport is connected by wedged
38 *
39 * This enumeration details the various states a transport
40 * instatiation can be in.
41 */
42
43enum p9_trans_status {
44 Connected,
45 BeginDisconnect,
46 Disconnected,
47 Hung,
48};
49
50/**
51 * enum p9_req_status_t - status of a request
52 * @REQ_STATUS_ALLOC: request has been allocated but not sent
53 * @REQ_STATUS_UNSENT: request waiting to be sent
54 * @REQ_STATUS_SENT: request sent to server
55 * @REQ_STATUS_RCVD: response received from server
56 * @REQ_STATUS_FLSHD: request has been flushed
57 * @REQ_STATUS_ERROR: request encountered an error on the client side
58 */
59
60enum p9_req_status_t {
61 REQ_STATUS_ALLOC,
62 REQ_STATUS_UNSENT,
63 REQ_STATUS_SENT,
64 REQ_STATUS_RCVD,
65 REQ_STATUS_FLSHD,
66 REQ_STATUS_ERROR,
67};
68
69/**
70 * struct p9_req_t - request slots
71 * @status: status of this request slot
72 * @t_err: transport error
73 * @wq: wait_queue for the client to block on for this request
74 * @tc: the request fcall structure
75 * @rc: the response fcall structure
76 * @req_list: link for higher level objects to chain requests
77 */
78struct p9_req_t {
79 int status;
80 int t_err;
81 struct kref refcount;
82 wait_queue_head_t wq;
83 struct p9_fcall tc;
84 struct p9_fcall rc;
85 struct list_head req_list;
86};
87
88/**
89 * struct p9_client - per client instance state
90 * @lock: protect @fids and @reqs
91 * @msize: maximum data size negotiated by protocol
92 * @proto_version: 9P protocol version to use
93 * @trans_mod: module API instantiated with this client
94 * @status: connection state
95 * @trans: tranport instance state and API
96 * @fids: All active FID handles
97 * @reqs: All active requests.
98 * @name: node name used as client id
99 *
100 * The client structure is used to keep track of various per-client
101 * state that has been instantiated.
102 */
103struct p9_client {
104 spinlock_t lock;
105 unsigned int msize;
106 unsigned char proto_version;
107 struct p9_trans_module *trans_mod;
108 enum p9_trans_status status;
109 void *trans;
110 struct kmem_cache *fcall_cache;
111
112 union {
113 struct {
114 int rfd;
115 int wfd;
116 } fd;
117 struct {
118 u16 port;
119 bool privport;
120
121 } tcp;
122 } trans_opts;
123
124 struct idr fids;
125 struct idr reqs;
126
127 char name[__NEW_UTS_LEN + 1];
128};
129
130/**
131 * struct p9_fid - file system entity handle
132 * @clnt: back pointer to instantiating &p9_client
133 * @fid: numeric identifier for this handle
134 * @mode: current mode of this fid (enum?)
135 * @qid: the &p9_qid server identifier this handle points to
136 * @iounit: the server reported maximum transaction size for this file
137 * @uid: the numeric uid of the local user who owns this handle
138 * @rdir: readdir accounting structure (allocated on demand)
139 * @dlist: per-dentry fid tracking
140 *
141 * TODO: This needs lots of explanation.
142 */
143
144struct p9_fid {
145 struct p9_client *clnt;
146 u32 fid;
147 int mode;
148 struct p9_qid qid;
149 u32 iounit;
150 kuid_t uid;
151
152 void *rdir;
153
154 struct hlist_node dlist; /* list of all fids attached to a dentry */
155};
156
157/**
158 * struct p9_dirent - directory entry structure
159 * @qid: The p9 server qid for this dirent
160 * @d_off: offset to the next dirent
161 * @d_type: type of file
162 * @d_name: file name
163 */
164
165struct p9_dirent {
166 struct p9_qid qid;
167 u64 d_off;
168 unsigned char d_type;
169 char d_name[256];
170};
171
172struct iov_iter;
173
174int p9_show_client_options(struct seq_file *m, struct p9_client *clnt);
175int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb);
176int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid,
177 const char *name);
178int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
179 struct p9_fid *newdirfid, const char *new_name);
180struct p9_client *p9_client_create(const char *dev_name, char *options);
181void p9_client_destroy(struct p9_client *clnt);
182void p9_client_disconnect(struct p9_client *clnt);
183void p9_client_begin_disconnect(struct p9_client *clnt);
184struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
185 const char *uname, kuid_t n_uname, const char *aname);
186struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
187 const unsigned char * const *wnames, int clone);
188int p9_client_open(struct p9_fid *fid, int mode);
189int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
190 char *extension);
191int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, const char *newname);
192int p9_client_symlink(struct p9_fid *fid, const char *name, const char *symname,
193 kgid_t gid, struct p9_qid *qid);
194int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, u32 mode,
195 kgid_t gid, struct p9_qid *qid);
196int p9_client_clunk(struct p9_fid *fid);
197int p9_client_fsync(struct p9_fid *fid, int datasync);
198int p9_client_remove(struct p9_fid *fid);
199int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags);
200int p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err);
201int p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to,
202 int *err);
203int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err);
204int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset);
205int p9dirent_read(struct p9_client *clnt, char *buf, int len,
206 struct p9_dirent *dirent);
207struct p9_wstat *p9_client_stat(struct p9_fid *fid);
208int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
209int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr);
210
211struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
212 u64 request_mask);
213
214int p9_client_mknod_dotl(struct p9_fid *oldfid, const char *name, int mode,
215 dev_t rdev, kgid_t gid, struct p9_qid *);
216int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
217 kgid_t gid, struct p9_qid *);
218int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
219int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
220void p9_fcall_fini(struct p9_fcall *fc);
221struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
222
223static inline void p9_req_get(struct p9_req_t *r)
224{
225 kref_get(&r->refcount);
226}
227
228static inline int p9_req_try_get(struct p9_req_t *r)
229{
230 return kref_get_unless_zero(&r->refcount);
231}
232
233int p9_req_put(struct p9_req_t *r);
234
235void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status);
236
237int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
238int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *);
239void p9stat_free(struct p9_wstat *);
240
241int p9_is_proto_dotu(struct p9_client *clnt);
242int p9_is_proto_dotl(struct p9_client *clnt);
243struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *);
244int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int);
245int p9_client_readlink(struct p9_fid *fid, char **target);
246
247int p9_client_init(void);
248void p9_client_exit(void);
249
250#endif /* NET_9P_CLIENT_H */