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
26 enum 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
43 enum 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
60 enum 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 */
78 struct 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 */
103 struct 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
144 struct 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
165 struct p9_dirent {
166 struct p9_qid qid;
167 u64 d_off;
168 unsigned char d_type;
169 char d_name[256];
170 };
171
172 struct iov_iter;
173
174 int p9_show_client_options(struct seq_file *m, struct p9_client *clnt);
175 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb);
176 int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid,
177 const char *name);
178 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
179 struct p9_fid *newdirfid, const char *new_name);
180 struct p9_client *p9_client_create(const char *dev_name, char *options);
181 void p9_client_destroy(struct p9_client *clnt);
182 void p9_client_disconnect(struct p9_client *clnt);
183 void p9_client_begin_disconnect(struct p9_client *clnt);
184 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
185 const char *uname, kuid_t n_uname, const char *aname);
186 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
187 const unsigned char * const *wnames, int clone);
188 int p9_client_open(struct p9_fid *fid, int mode);
189 int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
190 char *extension);
191 int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, const char *newname);
192 int p9_client_symlink(struct p9_fid *fid, const char *name, const char *symname,
193 kgid_t gid, struct p9_qid *qid);
194 int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, u32 mode,
195 kgid_t gid, struct p9_qid *qid);
196 int p9_client_clunk(struct p9_fid *fid);
197 int p9_client_fsync(struct p9_fid *fid, int datasync);
198 int p9_client_remove(struct p9_fid *fid);
199 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags);
200 int p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err);
201 int p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to,
202 int *err);
203 int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err);
204 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset);
205 int p9dirent_read(struct p9_client *clnt, char *buf, int len,
206 struct p9_dirent *dirent);
207 struct p9_wstat *p9_client_stat(struct p9_fid *fid);
208 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
209 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr);
210
211 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
212 u64 request_mask);
213
214 int p9_client_mknod_dotl(struct p9_fid *oldfid, const char *name, int mode,
215 dev_t rdev, kgid_t gid, struct p9_qid *);
216 int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
217 kgid_t gid, struct p9_qid *);
218 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
219 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
220 void p9_fcall_fini(struct p9_fcall *fc);
221 struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
222
p9_req_get(struct p9_req_t * r)223 static inline void p9_req_get(struct p9_req_t *r)
224 {
225 kref_get(&r->refcount);
226 }
227
p9_req_try_get(struct p9_req_t * r)228 static inline int p9_req_try_get(struct p9_req_t *r)
229 {
230 return kref_get_unless_zero(&r->refcount);
231 }
232
233 int p9_req_put(struct p9_req_t *r);
234
235 void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status);
236
237 int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
238 int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *);
239 void p9stat_free(struct p9_wstat *);
240
241 int p9_is_proto_dotu(struct p9_client *clnt);
242 int p9_is_proto_dotl(struct p9_client *clnt);
243 struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *);
244 int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int);
245 int p9_client_readlink(struct p9_fid *fid, char **target);
246
247 int p9_client_init(void);
248 void p9_client_exit(void);
249
250 #endif /* NET_9P_CLIENT_H */
251
