inout.c revision 243349 
1/*-
2 * Copyright (c) 2011 NetApp, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32#include <sys/param.h>
33#include <sys/linker_set.h>
34
35#include <stdio.h>
36#include <assert.h>
37
38#include "inout.h"
39
40SET_DECLARE(inout_port_set, struct inout_port);
41
42#define	MAX_IOPORTS	(1 << 16)
43
44static struct {
45	const char	*name;
46	int		flags;
47	inout_func_t	handler;
48	void		*arg;
49} inout_handlers[MAX_IOPORTS];
50
51static int
52default_inout(struct vmctx *ctx, int vcpu, int in, int port, int bytes,
53              uint32_t *eax, void *arg)
54{
55        if (in) {
56                switch (bytes) {
57                case 4:
58                        *eax = 0xffffffff;
59                        break;
60                case 2:
61                        *eax = 0xffff;
62                        break;
63                case 1:
64                        *eax = 0xff;
65                        break;
66                }
67        }
68
69        return (0);
70}
71
72int
73emulate_inout(struct vmctx *ctx, int vcpu, int in, int port, int bytes,
74	      uint32_t *eax, int strict)
75{
76	int flags;
77	uint32_t mask;
78	inout_func_t handler;
79	void *arg;
80
81	assert(port < MAX_IOPORTS);
82
83	handler = inout_handlers[port].handler;
84
85	if (strict && handler == default_inout)
86		return (-1);
87
88	if (!in) {
89		switch (bytes) {
90		case 1:
91			mask = 0xff;
92			break;
93		case 2:
94			mask = 0xffff;
95			break;
96		default:
97			mask = 0xffffffff;
98			break;
99		}
100		*eax = *eax & mask;
101	}
102
103	flags = inout_handlers[port].flags;
104	arg = inout_handlers[port].arg;
105
106	if ((in && (flags & IOPORT_F_IN)) || (!in && (flags & IOPORT_F_OUT)))
107		return ((*handler)(ctx, vcpu, in, port, bytes, eax, arg));
108	else
109		return (-1);
110}
111
112void
113init_inout(void)
114{
115	struct inout_port **iopp, *iop;
116	int i;
117
118	/*
119	 * Set up the default handler for all ports
120	 */
121	for (i = 0; i < MAX_IOPORTS; i++) {
122		inout_handlers[i].name = "default";
123		inout_handlers[i].flags = IOPORT_F_IN | IOPORT_F_OUT;
124		inout_handlers[i].handler = default_inout;
125		inout_handlers[i].arg = NULL;
126	}
127
128	/*
129	 * Overwrite with specified handlers
130	 */
131	SET_FOREACH(iopp, inout_port_set) {
132		iop = *iopp;
133		assert(iop->port < MAX_IOPORTS);
134		inout_handlers[iop->port].name = iop->name;
135		inout_handlers[iop->port].flags = iop->flags;
136		inout_handlers[iop->port].handler = iop->handler;
137		inout_handlers[iop->port].arg = NULL;
138	}
139}
140
141int
142register_inout(struct inout_port *iop)
143{
144	assert(iop->port < MAX_IOPORTS);
145	inout_handlers[iop->port].name = iop->name;
146	inout_handlers[iop->port].flags = iop->flags;
147	inout_handlers[iop->port].handler = iop->handler;
148	inout_handlers[iop->port].arg = iop->arg;
149
150	return (0);
151}
152