xref: /freebsd/sys/amd64/vmm/io/iommu.c (revision d96700a6da2afa88607fbd7405ade439424d10d9)
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/types.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/sysctl.h>
37 
38 #include <dev/pci/pcivar.h>
39 #include <dev/pci/pcireg.h>
40 
41 #include <machine/cpu.h>
42 #include <machine/md_var.h>
43 
44 #include "vmm_util.h"
45 #include "vmm_mem.h"
46 #include "iommu.h"
47 
48 SYSCTL_DECL(_hw_vmm);
49 SYSCTL_NODE(_hw_vmm, OID_AUTO, iommu, CTLFLAG_RW, 0, "bhyve iommu parameters");
50 
51 static int iommu_avail;
52 SYSCTL_INT(_hw_vmm_iommu, OID_AUTO, initialized, CTLFLAG_RD, &iommu_avail,
53     0, "bhyve iommu initialized?");
54 
55 static int iommu_enable = 1;
56 SYSCTL_INT(_hw_vmm_iommu, OID_AUTO, enable, CTLFLAG_RDTUN, &iommu_enable, 0,
57     "Enable use of I/O MMU (required for PCI passthrough).");
58 
59 static struct iommu_ops *ops;
60 static void *host_domain;
61 
62 static __inline int
63 IOMMU_INIT(void)
64 {
65 	if (ops != NULL)
66 		return ((*ops->init)());
67 	else
68 		return (ENXIO);
69 }
70 
71 static __inline void
72 IOMMU_CLEANUP(void)
73 {
74 	if (ops != NULL && iommu_avail)
75 		(*ops->cleanup)();
76 }
77 
78 static __inline void *
79 IOMMU_CREATE_DOMAIN(vm_paddr_t maxaddr)
80 {
81 
82 	if (ops != NULL && iommu_avail)
83 		return ((*ops->create_domain)(maxaddr));
84 	else
85 		return (NULL);
86 }
87 
88 static __inline void
89 IOMMU_DESTROY_DOMAIN(void *dom)
90 {
91 
92 	if (ops != NULL && iommu_avail)
93 		(*ops->destroy_domain)(dom);
94 }
95 
96 static __inline uint64_t
97 IOMMU_CREATE_MAPPING(void *domain, vm_paddr_t gpa, vm_paddr_t hpa, uint64_t len)
98 {
99 
100 	if (ops != NULL && iommu_avail)
101 		return ((*ops->create_mapping)(domain, gpa, hpa, len));
102 	else
103 		return (len);		/* XXX */
104 }
105 
106 static __inline uint64_t
107 IOMMU_REMOVE_MAPPING(void *domain, vm_paddr_t gpa, uint64_t len)
108 {
109 
110 	if (ops != NULL && iommu_avail)
111 		return ((*ops->remove_mapping)(domain, gpa, len));
112 	else
113 		return (len);		/* XXX */
114 }
115 
116 static __inline void
117 IOMMU_ADD_DEVICE(void *domain, uint16_t rid)
118 {
119 
120 	if (ops != NULL && iommu_avail)
121 		(*ops->add_device)(domain, rid);
122 }
123 
124 static __inline void
125 IOMMU_REMOVE_DEVICE(void *domain, uint16_t rid)
126 {
127 
128 	if (ops != NULL && iommu_avail)
129 		(*ops->remove_device)(domain, rid);
130 }
131 
132 static __inline void
133 IOMMU_INVALIDATE_TLB(void *domain)
134 {
135 
136 	if (ops != NULL && iommu_avail)
137 		(*ops->invalidate_tlb)(domain);
138 }
139 
140 static __inline void
141 IOMMU_ENABLE(void)
142 {
143 
144 	if (ops != NULL && iommu_avail)
145 		(*ops->enable)();
146 }
147 
148 static __inline void
149 IOMMU_DISABLE(void)
150 {
151 
152 	if (ops != NULL && iommu_avail)
153 		(*ops->disable)();
154 }
155 
156 static void
157 iommu_init(void)
158 {
159 	int error, bus, slot, func;
160 	vm_paddr_t maxaddr;
161 	const char *name;
162 	device_t dev;
163 
164 	if (!iommu_enable)
165 		return;
166 
167 	if (vmm_is_intel())
168 		ops = &iommu_ops_intel;
169 	else if (vmm_is_amd())
170 		ops = &iommu_ops_amd;
171 	else
172 		ops = NULL;
173 
174 	error = IOMMU_INIT();
175 	if (error)
176 		return;
177 
178 	iommu_avail = 1;
179 
180 	/*
181 	 * Create a domain for the devices owned by the host
182 	 */
183 	maxaddr = vmm_mem_maxaddr();
184 	host_domain = IOMMU_CREATE_DOMAIN(maxaddr);
185 	if (host_domain == NULL) {
186 		printf("iommu_init: unable to create a host domain");
187 		IOMMU_CLEANUP();
188 		ops = NULL;
189 		iommu_avail = 0;
190 		return;
191 	}
192 
193 	/*
194 	 * Create 1:1 mappings from '0' to 'maxaddr' for devices assigned to
195 	 * the host
196 	 */
197 	iommu_create_mapping(host_domain, 0, 0, maxaddr);
198 
199 	for (bus = 0; bus <= PCI_BUSMAX; bus++) {
200 		for (slot = 0; slot <= PCI_SLOTMAX; slot++) {
201 			for (func = 0; func <= PCI_FUNCMAX; func++) {
202 				dev = pci_find_dbsf(0, bus, slot, func);
203 				if (dev == NULL)
204 					continue;
205 
206 				/* skip passthrough devices */
207 				name = device_get_name(dev);
208 				if (name != NULL && strcmp(name, "ppt") == 0)
209 					continue;
210 
211 				/* everything else belongs to the host domain */
212 				iommu_add_device(host_domain,
213 				    pci_get_rid(dev));
214 			}
215 		}
216 	}
217 	IOMMU_ENABLE();
218 
219 }
220 
221 void
222 iommu_cleanup(void)
223 {
224 	IOMMU_DISABLE();
225 	IOMMU_DESTROY_DOMAIN(host_domain);
226 	IOMMU_CLEANUP();
227 }
228 
229 void *
230 iommu_create_domain(vm_paddr_t maxaddr)
231 {
232 	static volatile int iommu_initted;
233 
234 	if (iommu_initted < 2) {
235 		if (atomic_cmpset_int(&iommu_initted, 0, 1)) {
236 			iommu_init();
237 			atomic_store_rel_int(&iommu_initted, 2);
238 		} else
239 			while (iommu_initted == 1)
240 				cpu_spinwait();
241 	}
242 	return (IOMMU_CREATE_DOMAIN(maxaddr));
243 }
244 
245 void
246 iommu_destroy_domain(void *dom)
247 {
248 
249 	IOMMU_DESTROY_DOMAIN(dom);
250 }
251 
252 void
253 iommu_create_mapping(void *dom, vm_paddr_t gpa, vm_paddr_t hpa, size_t len)
254 {
255 	uint64_t mapped, remaining;
256 
257 	remaining = len;
258 
259 	while (remaining > 0) {
260 		mapped = IOMMU_CREATE_MAPPING(dom, gpa, hpa, remaining);
261 		gpa += mapped;
262 		hpa += mapped;
263 		remaining -= mapped;
264 	}
265 }
266 
267 void
268 iommu_remove_mapping(void *dom, vm_paddr_t gpa, size_t len)
269 {
270 	uint64_t unmapped, remaining;
271 
272 	remaining = len;
273 
274 	while (remaining > 0) {
275 		unmapped = IOMMU_REMOVE_MAPPING(dom, gpa, remaining);
276 		gpa += unmapped;
277 		remaining -= unmapped;
278 	}
279 }
280 
281 void *
282 iommu_host_domain(void)
283 {
284 
285 	return (host_domain);
286 }
287 
288 void
289 iommu_add_device(void *dom, uint16_t rid)
290 {
291 
292 	IOMMU_ADD_DEVICE(dom, rid);
293 }
294 
295 void
296 iommu_remove_device(void *dom, uint16_t rid)
297 {
298 
299 	IOMMU_REMOVE_DEVICE(dom, rid);
300 }
301 
302 void
303 iommu_invalidate_tlb(void *domain)
304 {
305 
306 	IOMMU_INVALIDATE_TLB(domain);
307 }
308