1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2014 Tycho Nightingale <tycho.nightingale@pluribusnetworks.com>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/param.h>
30#include <sys/systm.h>
31
32#include <machine/vmm.h>
33#include <machine/vmm_instruction_emul.h>
34
35#include "vatpic.h"
36#include "vatpit.h"
37#include "vpmtmr.h"
38#include "vrtc.h"
39#include "vmm_ioport.h"
40#include "vmm_ktr.h"
41
42#define	MAX_IOPORTS		1280
43
44ioport_handler_func_t ioport_handler[MAX_IOPORTS] = {
45	[TIMER_MODE] = vatpit_handler,
46	[TIMER_CNTR0] = vatpit_handler,
47	[TIMER_CNTR1] = vatpit_handler,
48	[TIMER_CNTR2] = vatpit_handler,
49	[NMISC_PORT] = vatpit_nmisc_handler,
50	[IO_ICU1] = vatpic_master_handler,
51	[IO_ICU1 + ICU_IMR_OFFSET] = vatpic_master_handler,
52	[IO_ICU2] = vatpic_slave_handler,
53	[IO_ICU2 + ICU_IMR_OFFSET] = vatpic_slave_handler,
54	[IO_ELCR1] = vatpic_elc_handler,
55	[IO_ELCR2] = vatpic_elc_handler,
56	[IO_PMTMR] = vpmtmr_handler,
57	[IO_RTC] = vrtc_addr_handler,
58	[IO_RTC + 1] = vrtc_data_handler,
59};
60
61#ifdef KTR
62static const char *
63inout_instruction(struct vm_exit *vmexit)
64{
65	int index;
66
67	static const char *iodesc[] = {
68		"outb", "outw", "outl",
69		"inb", "inw", "inl",
70		"outsb", "outsw", "outsd",
71		"insb", "insw", "insd",
72	};
73
74	switch (vmexit->u.inout.bytes) {
75	case 1:
76		index = 0;
77		break;
78	case 2:
79		index = 1;
80		break;
81	default:
82		index = 2;
83		break;
84	}
85
86	if (vmexit->u.inout.in)
87		index += 3;
88
89	if (vmexit->u.inout.string)
90		index += 6;
91
92	KASSERT(index < nitems(iodesc), ("%s: invalid index %d",
93	    __func__, index));
94
95	return (iodesc[index]);
96}
97#endif	/* KTR */
98
99static int
100emulate_inout_port(struct vcpu *vcpu, struct vm_exit *vmexit, bool *retu)
101{
102	ioport_handler_func_t handler;
103	uint32_t mask, val;
104	int error;
105
106	/*
107	 * If there is no handler for the I/O port then punt to userspace.
108	 */
109	if (vmexit->u.inout.port >= MAX_IOPORTS ||
110	    (handler = ioport_handler[vmexit->u.inout.port]) == NULL) {
111		*retu = true;
112		return (0);
113	}
114
115	mask = vie_size2mask(vmexit->u.inout.bytes);
116
117	if (!vmexit->u.inout.in) {
118		val = vmexit->u.inout.eax & mask;
119	}
120
121	error = (*handler)(vcpu_vm(vcpu), vmexit->u.inout.in,
122	    vmexit->u.inout.port, vmexit->u.inout.bytes, &val);
123	if (error) {
124		/*
125		 * The value returned by this function is also the return value
126		 * of vm_run(). This needs to be a positive number otherwise it
127		 * can be interpreted as a "pseudo-error" like ERESTART.
128		 *
129		 * Enforce this by mapping all errors to EIO.
130		 */
131		return (EIO);
132	}
133
134	if (vmexit->u.inout.in) {
135		vmexit->u.inout.eax &= ~mask;
136		vmexit->u.inout.eax |= val & mask;
137		error = vm_set_register(vcpu, VM_REG_GUEST_RAX,
138		    vmexit->u.inout.eax);
139		KASSERT(error == 0, ("emulate_ioport: error %d setting guest "
140		    "rax register", error));
141	}
142	*retu = false;
143	return (0);
144}
145
146static int
147emulate_inout_str(struct vcpu *vcpu, struct vm_exit *vmexit, bool *retu)
148{
149	*retu = true;
150	return (0);	/* Return to userspace to finish emulation */
151}
152
153int
154vm_handle_inout(struct vcpu *vcpu, struct vm_exit *vmexit, bool *retu)
155{
156	int bytes __diagused, error;
157
158	bytes = vmexit->u.inout.bytes;
159	KASSERT(bytes == 1 || bytes == 2 || bytes == 4,
160	    ("vm_handle_inout: invalid operand size %d", bytes));
161
162	if (vmexit->u.inout.string)
163		error = emulate_inout_str(vcpu, vmexit, retu);
164	else
165		error = emulate_inout_port(vcpu, vmexit, retu);
166
167	VCPU_CTR4(vcpu_vm(vcpu), vcpu_vcpuid(vcpu), "%s%s 0x%04x: %s",
168	    vmexit->u.inout.rep ? "rep " : "",
169	    inout_instruction(vmexit),
170	    vmexit->u.inout.port,
171	    error ? "error" : (*retu ? "userspace" : "handled"));
172
173	return (error);
174}
175