xref: /openbmc/linux/include/net/9p/transport.h (revision e65e175b)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Transport Definition
4  *
5  *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
6  *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
7  */
8 
9 #ifndef NET_9P_TRANSPORT_H
10 #define NET_9P_TRANSPORT_H
11 
12 #include <linux/module.h>
13 
14 #define P9_DEF_MIN_RESVPORT	(665U)
15 #define P9_DEF_MAX_RESVPORT	(1023U)
16 
17 /**
18  * struct p9_trans_module - transport module interface
19  * @list: used to maintain a list of currently available transports
20  * @name: the human-readable name of the transport
21  * @maxsize: transport provided maximum packet size
22  * @pooled_rbuffers: currently only set for RDMA transport which pulls the
23  *                   response buffers from a shared pool, and accordingly
24  *                   we're less flexible when choosing the response message
25  *                   size in this case
26  * @def: set if this transport should be considered the default
27  * @create: member function to create a new connection on this transport
28  * @close: member function to discard a connection on this transport
29  * @request: member function to issue a request to the transport
30  * @cancel: member function to cancel a request (if it hasn't been sent)
31  * @cancelled: member function to notify that a cancelled request will not
32  *             receive a reply
33  *
34  * This is the basic API for a transport module which is registered by the
35  * transport module with the 9P core network module and used by the client
36  * to instantiate a new connection on a transport.
37  *
38  * The transport module list is protected by v9fs_trans_lock.
39  */
40 
41 struct p9_trans_module {
42 	struct list_head list;
43 	char *name;		/* name of transport */
44 	int maxsize;		/* max message size of transport */
45 	bool pooled_rbuffers;
46 	int def;		/* this transport should be default */
47 	struct module *owner;
48 	int (*create)(struct p9_client *client,
49 		      const char *devname, char *args);
50 	void (*close)(struct p9_client *client);
51 	int (*request)(struct p9_client *client, struct p9_req_t *req);
52 	int (*cancel)(struct p9_client *client, struct p9_req_t *req);
53 	int (*cancelled)(struct p9_client *client, struct p9_req_t *req);
54 	int (*zc_request)(struct p9_client *client, struct p9_req_t *req,
55 			  struct iov_iter *uidata, struct iov_iter *uodata,
56 			  int inlen, int outlen, int in_hdr_len);
57 	int (*show_options)(struct seq_file *m, struct p9_client *client);
58 };
59 
60 void v9fs_register_trans(struct p9_trans_module *m);
61 void v9fs_unregister_trans(struct p9_trans_module *m);
62 struct p9_trans_module *v9fs_get_trans_by_name(const char *s);
63 struct p9_trans_module *v9fs_get_default_trans(void);
64 void v9fs_put_trans(struct p9_trans_module *m);
65 
66 #define MODULE_ALIAS_9P(transport) \
67 	MODULE_ALIAS("9p-" transport)
68 
69 #endif /* NET_9P_TRANSPORT_H */
70