| 1 | /* |
| 2 | * include/net/9p/transport.h |
| 3 | * |
| 4 | * Transport Definition |
| 5 | * |
| 6 | * Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net> |
| 7 | * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> |
| 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_TRANSPORT_H |
| 27 | #define NET_9P_TRANSPORT_H |
| 28 | |
| 29 | #include <linux/module.h> |
| 30 | |
| 31 | /** |
| 32 | * enum p9_trans_status - different states of underlying transports |
| 33 | * @Connected: transport is connected and healthy |
| 34 | * @Disconnected: transport has been disconnected |
| 35 | * @Hung: transport is connected by wedged |
| 36 | * |
| 37 | * This enumeration details the various states a transport |
| 38 | * instatiation can be in. |
| 39 | */ |
| 40 | |
| 41 | enum p9_trans_status { |
| 42 | Connected, |
| 43 | Disconnected, |
| 44 | Hung, |
| 45 | }; |
| 46 | |
| 47 | /** |
| 48 | * struct p9_trans - per-transport state and API |
| 49 | * @status: transport &p9_trans_status |
| 50 | * @msize: negotiated maximum packet size (duplicate from client) |
| 51 | * @extended: negotiated protocol extensions (duplicate from client) |
| 52 | * @priv: transport private data |
| 53 | * @close: member function to disconnect and close the transport |
| 54 | * @rpc: member function to issue a request to the transport |
| 55 | * |
| 56 | * This is the basic API for a transport instance. It is used as |
| 57 | * a handle by the client to issue requests. This interface is currently |
| 58 | * in flux during reorganization. |
| 59 | * |
| 60 | * Bugs: there is lots of duplicated data here and its not clear that |
| 61 | * the member functions need to be per-instance versus per transport |
| 62 | * module. |
| 63 | */ |
| 64 | |
| 65 | struct p9_trans { |
| 66 | enum p9_trans_status status; |
| 67 | int msize; |
| 68 | unsigned char extended; |
| 69 | void *priv; |
| 70 | void (*close) (struct p9_trans *); |
| 71 | int (*rpc) (struct p9_trans *t, struct p9_fcall *tc, |
| 72 | struct p9_fcall **rc); |
| 73 | }; |
| 74 | |
| 75 | /** |
| 76 | * struct p9_trans_module - transport module interface |
| 77 | * @list: used to maintain a list of currently available transports |
| 78 | * @name: the human-readable name of the transport |
| 79 | * @maxsize: transport provided maximum packet size |
| 80 | * @def: set if this transport should be considered the default |
| 81 | * @create: member function to create a new connection on this transport |
| 82 | * |
| 83 | * This is the basic API for a transport module which is registered by the |
| 84 | * transport module with the 9P core network module and used by the client |
| 85 | * to instantiate a new connection on a transport. |
| 86 | * |
| 87 | * Bugs: the transport module list isn't protected. |
| 88 | */ |
| 89 | |
| 90 | struct p9_trans_module { |
| 91 | struct list_head list; |
| 92 | char *name; /* name of transport */ |
| 93 | int maxsize; /* max message size of transport */ |
| 94 | int def; /* this transport should be default */ |
| 95 | struct p9_trans * (*create)(const char *, char *, int, unsigned char); |
| 96 | struct module *owner; |
| 97 | }; |
| 98 | |
| 99 | void v9fs_register_trans(struct p9_trans_module *m); |
| 100 | void v9fs_unregister_trans(struct p9_trans_module *m); |
| 101 | struct p9_trans_module *v9fs_get_trans_by_name(const substring_t *name); |
| 102 | struct p9_trans_module *v9fs_get_default_trans(void); |
| 103 | void v9fs_put_trans(struct p9_trans_module *m); |
| 104 | #endif /* NET_9P_TRANSPORT_H */ |