1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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/cdefs.h>
30__FBSDID("$FreeBSD: stable/11/sys/amd64/vmm/vmm_ioport.c 336190 2018-07-11 07:19:42Z araujo $");
31
32#include <sys/param.h>
33#include <sys/systm.h>
34
35#include <machine/vmm.h>
36#include <machine/vmm_instruction_emul.h>
37
38#include "vatpic.h"
39#include "vatpit.h"
40#include "vpmtmr.h"
41#include "vrtc.h"
42#include "vmm_ioport.h"
43#include "vmm_ktr.h"
44
45#define	MAX_IOPORTS		1280
46
47ioport_handler_func_t ioport_handler[MAX_IOPORTS] = {
48	[TIMER_MODE] = vatpit_handler,
49	[TIMER_CNTR0] = vatpit_handler,
50	[TIMER_CNTR1] = vatpit_handler,
51	[TIMER_CNTR2] = vatpit_handler,
52	[NMISC_PORT] = vatpit_nmisc_handler,
53	[IO_ICU1] = vatpic_master_handler,
54	[IO_ICU1 + ICU_IMR_OFFSET] = vatpic_master_handler,
55	[IO_ICU2] = vatpic_slave_handler,
56	[IO_ICU2 + ICU_IMR_OFFSET] = vatpic_slave_handler,
57	[IO_ELCR1] = vatpic_elc_handler,
58	[IO_ELCR2] = vatpic_elc_handler,
59	[IO_PMTMR] = vpmtmr_handler,
60	[IO_RTC] = vrtc_addr_handler,
61	[IO_RTC + 1] = vrtc_data_handler,
62};
63
64#ifdef KTR
65static const char *
66inout_instruction(struct vm_exit *vmexit)
67{
68	int index;
69
70	static const char *iodesc[] = {
71		"outb", "outw", "outl",
72		"inb", "inw", "inl",
73		"outsb", "outsw", "outsd",
74		"insb", "insw", "insd",
75	};
76
77	switch (vmexit->u.inout.bytes) {
78	case 1:
79		index = 0;
80		break;
81	case 2:
82		index = 1;
83		break;
84	default:
85		index = 2;
86		break;
87	}
88
89	if (vmexit->u.inout.in)
90		index += 3;
91
92	if (vmexit->u.inout.string)
93		index += 6;
94
95	KASSERT(index < nitems(iodesc), ("%s: invalid index %d",
96	    __func__, index));
97
98	return (iodesc[index]);
99}
100#endif	/* KTR */
101
102static int
103emulate_inout_port(struct vm *vm, int vcpuid, struct vm_exit *vmexit,
104    bool *retu)
105{
106	ioport_handler_func_t handler;
107	uint32_t mask, val;
108	int error;
109
110	/*
111	 * If there is no handler for the I/O port then punt to userspace.
112	 */
113	if (vmexit->u.inout.port >= MAX_IOPORTS ||
114	    (handler = ioport_handler[vmexit->u.inout.port]) == NULL) {
115		*retu = true;
116		return (0);
117	}
118
119	mask = vie_size2mask(vmexit->u.inout.bytes);
120
121	if (!vmexit->u.inout.in) {
122		val = vmexit->u.inout.eax & mask;
123	}
124
125	error = (*handler)(vm, vcpuid, vmexit->u.inout.in,
126	    vmexit->u.inout.port, vmexit->u.inout.bytes, &val);
127	if (error) {
128		/*
129		 * The value returned by this function is also the return value
130		 * of vm_run(). This needs to be a positive number otherwise it
131		 * can be interpreted as a "pseudo-error" like ERESTART.
132		 *
133		 * Enforce this by mapping all errors to EIO.
134		 */
135		return (EIO);
136	}
137
138	if (vmexit->u.inout.in) {
139		vmexit->u.inout.eax &= ~mask;
140		vmexit->u.inout.eax |= val & mask;
141		error = vm_set_register(vm, vcpuid, VM_REG_GUEST_RAX,
142		    vmexit->u.inout.eax);
143		KASSERT(error == 0, ("emulate_ioport: error %d setting guest "
144		    "rax register", error));
145	}
146	*retu = false;
147	return (0);
148}
149
150static int
151emulate_inout_str(struct vm *vm, int vcpuid, struct vm_exit *vmexit, bool *retu)
152{
153	*retu = true;
154	return (0);	/* Return to userspace to finish emulation */
155}
156
157int
158vm_handle_inout(struct vm *vm, int vcpuid, struct vm_exit *vmexit, bool *retu)
159{
160	int bytes, error;
161
162	bytes = vmexit->u.inout.bytes;
163	KASSERT(bytes == 1 || bytes == 2 || bytes == 4,
164	    ("vm_handle_inout: invalid operand size %d", bytes));
165
166	if (vmexit->u.inout.string)
167		error = emulate_inout_str(vm, vcpuid, vmexit, retu);
168	else
169		error = emulate_inout_port(vm, vcpuid, vmexit, retu);
170
171	VCPU_CTR4(vm, vcpuid, "%s%s 0x%04x: %s",
172	    vmexit->u.inout.rep ? "rep " : "",
173	    inout_instruction(vmexit),
174	    vmexit->u.inout.port,
175	    error ? "error" : (*retu ? "userspace" : "handled"));
176
177	return (error);
178}
179