xref: /linux/include/net/9p/transport.h (revision bbbf7f32843b5788786cd8d91e9430823c2777c9)
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 #define P9_FD_PORT 564
18 
19 #define P9_RDMA_PORT		5640
20 #define P9_RDMA_SQ_DEPTH	32
21 #define P9_RDMA_RQ_DEPTH	32
22 #define P9_RDMA_TIMEOUT		30000		/* 30 seconds */
23 
24 /**
25  * struct p9_trans_module - transport module interface
26  * @list: used to maintain a list of currently available transports
27  * @name: the human-readable name of the transport
28  * @maxsize: transport provided maximum packet size
29  * @pooled_rbuffers: currently only set for RDMA transport which pulls the
30  *                   response buffers from a shared pool, and accordingly
31  *                   we're less flexible when choosing the response message
32  *                   size in this case
33  * @def: set if this transport should be considered the default
34  * @supports_vmalloc: set if this transport can work with vmalloc'd buffers
35  *                    (non-physically contiguous memory). Transports requiring
36  *                    DMA should leave this as false.
37  * @create: member function to create a new connection on this transport
38  * @close: member function to discard a connection on this transport
39  * @request: member function to issue a request to the transport
40  * @cancel: member function to cancel a request (if it hasn't been sent)
41  * @cancelled: member function to notify that a cancelled request will not
42  *             receive a reply
43  *
44  * This is the basic API for a transport module which is registered by the
45  * transport module with the 9P core network module and used by the client
46  * to instantiate a new connection on a transport.
47  *
48  * The transport module list is protected by v9fs_trans_lock.
49  */
50 
51 struct p9_trans_module {
52 	struct list_head list;
53 	char *name;		/* name of transport */
54 	int maxsize;		/* max message size of transport */
55 	bool pooled_rbuffers;
56 	bool def;		/* this transport should be default */
57 	bool supports_vmalloc;	/* can work with vmalloc'd buffers */
58 	struct module *owner;
59 	int (*create)(struct p9_client *client,
60 		      struct fs_context *fc);
61 	void (*close)(struct p9_client *client);
62 	int (*request)(struct p9_client *client, struct p9_req_t *req);
63 	int (*cancel)(struct p9_client *client, struct p9_req_t *req);
64 	int (*cancelled)(struct p9_client *client, struct p9_req_t *req);
65 	int (*zc_request)(struct p9_client *client, struct p9_req_t *req,
66 			  struct iov_iter *uidata, struct iov_iter *uodata,
67 			  int inlen, int outlen, int in_hdr_len);
68 	int (*show_options)(struct seq_file *m, struct p9_client *client);
69 };
70 
71 void v9fs_register_trans(struct p9_trans_module *m);
72 void v9fs_unregister_trans(struct p9_trans_module *m);
73 struct p9_trans_module *v9fs_get_trans_by_name(const char *s);
74 struct p9_trans_module *v9fs_get_default_trans(void);
75 void v9fs_put_trans(struct p9_trans_module *m);
76 
77 #define MODULE_ALIAS_9P(transport) \
78 	MODULE_ALIAS("9p-" transport)
79 
80 #endif /* NET_9P_TRANSPORT_H */
81