xref: /freebsd/sys/amd64/vmm/io/iommu.c (revision e3d9ae4c56e15404846e4cb3360394a0a36cec23)
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 	device_t dev;
162 
163 	if (!iommu_enable)
164 		return;
165 
166 	if (vmm_is_intel())
167 		ops = &iommu_ops_intel;
168 	else if (vmm_is_amd())
169 		ops = &iommu_ops_amd;
170 	else
171 		ops = NULL;
172 
173 	error = IOMMU_INIT();
174 	if (error)
175 		return;
176 
177 	iommu_avail = 1;
178 
179 	/*
180 	 * Create a domain for the devices owned by the host
181 	 */
182 	maxaddr = vmm_mem_maxaddr();
183 	host_domain = IOMMU_CREATE_DOMAIN(maxaddr);
184 	if (host_domain == NULL) {
185 		printf("iommu_init: unable to create a host domain");
186 		IOMMU_CLEANUP();
187 		ops = NULL;
188 		iommu_avail = 0;
189 		return;
190 	}
191 
192 	/*
193 	 * Create 1:1 mappings from '0' to 'maxaddr' for devices assigned to
194 	 * the host
195 	 */
196 	iommu_create_mapping(host_domain, 0, 0, maxaddr);
197 
198 	for (bus = 0; bus <= PCI_BUSMAX; bus++) {
199 		for (slot = 0; slot <= PCI_SLOTMAX; slot++) {
200 			for (func = 0; func <= PCI_FUNCMAX; func++) {
201 				dev = pci_find_dbsf(0, bus, slot, func);
202 				if (dev == NULL)
203 					continue;
204 
205 				/* Everything belongs to the host domain. */
206 				iommu_add_device(host_domain,
207 				    pci_get_rid(dev));
208 			}
209 		}
210 	}
211 	IOMMU_ENABLE();
212 
213 }
214 
215 void
216 iommu_cleanup(void)
217 {
218 	IOMMU_DISABLE();
219 	IOMMU_DESTROY_DOMAIN(host_domain);
220 	IOMMU_CLEANUP();
221 }
222 
223 void *
224 iommu_create_domain(vm_paddr_t maxaddr)
225 {
226 	static volatile int iommu_initted;
227 
228 	if (iommu_initted < 2) {
229 		if (atomic_cmpset_int(&iommu_initted, 0, 1)) {
230 			iommu_init();
231 			atomic_store_rel_int(&iommu_initted, 2);
232 		} else
233 			while (iommu_initted == 1)
234 				cpu_spinwait();
235 	}
236 	return (IOMMU_CREATE_DOMAIN(maxaddr));
237 }
238 
239 void
240 iommu_destroy_domain(void *dom)
241 {
242 
243 	IOMMU_DESTROY_DOMAIN(dom);
244 }
245 
246 void
247 iommu_create_mapping(void *dom, vm_paddr_t gpa, vm_paddr_t hpa, size_t len)
248 {
249 	uint64_t mapped, remaining;
250 
251 	remaining = len;
252 
253 	while (remaining > 0) {
254 		mapped = IOMMU_CREATE_MAPPING(dom, gpa, hpa, remaining);
255 		gpa += mapped;
256 		hpa += mapped;
257 		remaining -= mapped;
258 	}
259 }
260 
261 void
262 iommu_remove_mapping(void *dom, vm_paddr_t gpa, size_t len)
263 {
264 	uint64_t unmapped, remaining;
265 
266 	remaining = len;
267 
268 	while (remaining > 0) {
269 		unmapped = IOMMU_REMOVE_MAPPING(dom, gpa, remaining);
270 		gpa += unmapped;
271 		remaining -= unmapped;
272 	}
273 }
274 
275 void *
276 iommu_host_domain(void)
277 {
278 
279 	return (host_domain);
280 }
281 
282 void
283 iommu_add_device(void *dom, uint16_t rid)
284 {
285 
286 	IOMMU_ADD_DEVICE(dom, rid);
287 }
288 
289 void
290 iommu_remove_device(void *dom, uint16_t rid)
291 {
292 
293 	IOMMU_REMOVE_DEVICE(dom, rid);
294 }
295 
296 void
297 iommu_invalidate_tlb(void *domain)
298 {
299 
300 	IOMMU_INVALIDATE_TLB(domain);
301 }
302