xref: /illumos-gate/usr/src/cmd/bhyve/amd64/inout.c (revision 5c4a5fe1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 NetApp, Inc.
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 NETAPP, INC ``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 NETAPP, INC 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  * This file and its contents are supplied under the terms of the
30  * Common Development and Distribution License ("CDDL"), version 1.0.
31  * You may only use this file in accordance with the terms of version
32  * 1.0 of the CDDL.
33  *
34  * A full copy of the text of the CDDL should have accompanied this
35  * source.  A copy of the CDDL is also available via the Internet at
36  * http://www.illumos.org/license/CDDL.
37  *
38  * Copyright 2020 Oxide Computer Company
39  */
40 
41 
42 #include <sys/param.h>
43 #include <sys/linker_set.h>
44 #include <sys/_iovec.h>
45 #include <sys/mman.h>
46 
47 #include <x86/psl.h>
48 #include <x86/segments.h>
49 
50 #include <machine/vmm.h>
51 #include <vmmapi.h>
52 
53 #include <stdio.h>
54 #include <string.h>
55 #include <assert.h>
56 
57 #include "bhyverun.h"
58 #include "config.h"
59 #include "inout.h"
60 
61 SET_DECLARE(inout_port_set, struct inout_port);
62 
63 #define	MAX_IOPORTS	(1 << 16)
64 
65 #define	VERIFY_IOPORT(port, size) \
66 	assert((port) >= 0 && (size) > 0 && ((port) + (size)) <= MAX_IOPORTS)
67 
68 struct inout_handler {
69 	const char	*name;
70 	int		flags;
71 	inout_func_t	handler;
72 	void		*arg;
73 };
74 
75 static struct inout_handler inout_handlers[MAX_IOPORTS];
76 
77 static int
default_inout(struct vmctx * ctx __unused,int in,int port __unused,int bytes,uint32_t * eax,void * arg __unused)78 default_inout(struct vmctx *ctx __unused, int in,
79     int port __unused, int bytes, uint32_t *eax, void *arg __unused)
80 {
81 	if (in) {
82 		switch (bytes) {
83 		case 4:
84 			*eax = 0xffffffff;
85 			break;
86 		case 2:
87 			*eax = 0xffff;
88 			break;
89 		case 1:
90 			*eax = 0xff;
91 			break;
92 		}
93 	}
94 
95 	return (0);
96 }
97 
98 static void
register_default_iohandler(int start,int size)99 register_default_iohandler(int start, int size)
100 {
101 	struct inout_port iop;
102 
103 	VERIFY_IOPORT(start, size);
104 
105 	bzero(&iop, sizeof(iop));
106 	iop.name = "default";
107 	iop.port = start;
108 	iop.size = size;
109 	iop.flags = IOPORT_F_INOUT | IOPORT_F_DEFAULT;
110 	iop.handler = default_inout;
111 
112 	register_inout(&iop);
113 }
114 
115 int
emulate_inout(struct vmctx * ctx,struct vcpu * vcpu,struct vm_inout * inout)116 emulate_inout(struct vmctx *ctx, struct vcpu *vcpu, struct vm_inout *inout)
117 {
118 	struct inout_handler handler;
119 	inout_func_t hfunc;
120 	void *harg;
121 	int error;
122 	uint8_t bytes;
123 	bool in;
124 
125 	bytes = inout->bytes;
126 	in = (inout->flags & INOUT_IN) != 0;
127 
128 	assert(bytes == 1 || bytes == 2 || bytes == 4);
129 
130 	handler = inout_handlers[inout->port];
131 	hfunc = handler.handler;
132 	harg = handler.arg;
133 
134 	if (hfunc == default_inout &&
135 	    get_config_bool_default("x86.strictio", false))
136 		return (-1);
137 
138 	if (in) {
139 		if (!(handler.flags & IOPORT_F_IN))
140 			return (-1);
141 	} else {
142 		if (!(handler.flags & IOPORT_F_OUT))
143 			return (-1);
144 	}
145 
146 	error = hfunc(ctx, in, inout->port, bytes, &inout->eax, harg);
147 	return (error);
148 }
149 
150 void
init_inout(void)151 init_inout(void)
152 {
153 	struct inout_port **iopp, *iop;
154 
155 	/*
156 	 * Set up the default handler for all ports
157 	 */
158 	register_default_iohandler(0, MAX_IOPORTS);
159 
160 	/*
161 	 * Overwrite with specified handlers
162 	 */
163 	SET_FOREACH(iopp, inout_port_set) {
164 		iop = *iopp;
165 		assert(iop->port < MAX_IOPORTS);
166 		inout_handlers[iop->port].name = iop->name;
167 		inout_handlers[iop->port].flags = iop->flags;
168 		inout_handlers[iop->port].handler = iop->handler;
169 		inout_handlers[iop->port].arg = NULL;
170 	}
171 }
172 
173 int
register_inout(struct inout_port * iop)174 register_inout(struct inout_port *iop)
175 {
176 	int i;
177 
178 	VERIFY_IOPORT(iop->port, iop->size);
179 
180 	/*
181 	 * Verify that the new registration is not overwriting an already
182 	 * allocated i/o range.
183 	 */
184 	if ((iop->flags & IOPORT_F_DEFAULT) == 0) {
185 		for (i = iop->port; i < iop->port + iop->size; i++) {
186 			if ((inout_handlers[i].flags & IOPORT_F_DEFAULT) == 0)
187 				return (-1);
188 		}
189 	}
190 
191 	for (i = iop->port; i < iop->port + iop->size; i++) {
192 		inout_handlers[i].name = iop->name;
193 		inout_handlers[i].flags = iop->flags;
194 		inout_handlers[i].handler = iop->handler;
195 		inout_handlers[i].arg = iop->arg;
196 	}
197 
198 	return (0);
199 }
200 
201 int
unregister_inout(struct inout_port * iop)202 unregister_inout(struct inout_port *iop)
203 {
204 
205 	VERIFY_IOPORT(iop->port, iop->size);
206 	assert(inout_handlers[iop->port].name == iop->name);
207 
208 	register_default_iohandler(iop->port, iop->size);
209 
210 	return (0);
211 }
212