xref: /openbmc/qemu/hw/i386/sgx.c (revision ecd6f6a8)
1 /*
2  * SGX common code
3  *
4  * Copyright (C) 2021 Intel Corporation
5  *
6  * Authors:
7  *   Yang Zhong<yang.zhong@intel.com>
8  *   Sean Christopherson <sean.j.christopherson@intel.com>
9  *
10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
11  * See the COPYING file in the top-level directory.
12  */
13 #include "qemu/osdep.h"
14 #include "hw/i386/pc.h"
15 #include "hw/i386/sgx-epc.h"
16 #include "hw/mem/memory-device.h"
17 #include "monitor/qdev.h"
18 #include "monitor/monitor.h"
19 #include "monitor/hmp-target.h"
20 #include "qapi/error.h"
21 #include "qemu/error-report.h"
22 #include "qapi/qapi-commands-misc-target.h"
23 #include "exec/address-spaces.h"
24 #include "sysemu/hw_accel.h"
25 #include "sysemu/reset.h"
26 #include <sys/ioctl.h>
27 #include "hw/acpi/aml-build.h"
28 
29 #define SGX_MAX_EPC_SECTIONS            8
30 #define SGX_CPUID_EPC_INVALID           0x0
31 
32 /* A valid EPC section. */
33 #define SGX_CPUID_EPC_SECTION           0x1
34 #define SGX_CPUID_EPC_MASK              0xF
35 
36 #define SGX_MAGIC 0xA4
37 #define SGX_IOC_VEPC_REMOVE_ALL       _IO(SGX_MAGIC, 0x04)
38 
39 #define RETRY_NUM                       2
40 
41 static int sgx_epc_device_list(Object *obj, void *opaque)
42 {
43     GSList **list = opaque;
44 
45     if (object_dynamic_cast(obj, TYPE_SGX_EPC)) {
46         *list = g_slist_append(*list, DEVICE(obj));
47     }
48 
49     object_child_foreach(obj, sgx_epc_device_list, opaque);
50     return 0;
51 }
52 
53 static GSList *sgx_epc_get_device_list(void)
54 {
55     GSList *list = NULL;
56 
57     object_child_foreach(qdev_get_machine(), sgx_epc_device_list, &list);
58     return list;
59 }
60 
61 void sgx_epc_build_srat(GArray *table_data)
62 {
63     GSList *device_list = sgx_epc_get_device_list();
64 
65     for (; device_list; device_list = device_list->next) {
66         DeviceState *dev = device_list->data;
67         Object *obj = OBJECT(dev);
68         uint64_t addr, size;
69         int node;
70 
71         node = object_property_get_uint(obj, SGX_EPC_NUMA_NODE_PROP,
72                                         &error_abort);
73         addr = object_property_get_uint(obj, SGX_EPC_ADDR_PROP, &error_abort);
74         size = object_property_get_uint(obj, SGX_EPC_SIZE_PROP, &error_abort);
75 
76         build_srat_memory(table_data, addr, size, node, MEM_AFFINITY_ENABLED);
77     }
78     g_slist_free(device_list);
79 }
80 
81 static uint64_t sgx_calc_section_metric(uint64_t low, uint64_t high)
82 {
83     return (low & MAKE_64BIT_MASK(12, 20)) +
84            ((high & MAKE_64BIT_MASK(0, 20)) << 32);
85 }
86 
87 static SGXEPCSectionList *sgx_calc_host_epc_sections(void)
88 {
89     SGXEPCSectionList *head = NULL, **tail = &head;
90     SGXEPCSection *section;
91     uint32_t i, type;
92     uint32_t eax, ebx, ecx, edx;
93     uint32_t j = 0;
94 
95     for (i = 0; i < SGX_MAX_EPC_SECTIONS; i++) {
96         host_cpuid(0x12, i + 2, &eax, &ebx, &ecx, &edx);
97 
98         type = eax & SGX_CPUID_EPC_MASK;
99         if (type == SGX_CPUID_EPC_INVALID) {
100             break;
101         }
102 
103         if (type != SGX_CPUID_EPC_SECTION) {
104             break;
105         }
106 
107         section = g_new0(SGXEPCSection, 1);
108         section->node = j++;
109         section->size = sgx_calc_section_metric(ecx, edx);
110         QAPI_LIST_APPEND(tail, section);
111     }
112 
113     return head;
114 }
115 
116 static void sgx_epc_reset(void *opaque)
117 {
118     PCMachineState *pcms = PC_MACHINE(qdev_get_machine());
119     HostMemoryBackend *hostmem;
120     SGXEPCDevice *epc;
121     int failures;
122     int fd, i, j, r;
123     static bool warned = false;
124 
125     /*
126      * The second pass is needed to remove SECS pages that could not
127      * be removed during the first.
128      */
129     for (i = 0; i < RETRY_NUM; i++) {
130         failures = 0;
131         for (j = 0; j < pcms->sgx_epc.nr_sections; j++) {
132             epc = pcms->sgx_epc.sections[j];
133             hostmem = MEMORY_BACKEND(epc->hostmem);
134             fd = memory_region_get_fd(host_memory_backend_get_memory(hostmem));
135 
136             r = ioctl(fd, SGX_IOC_VEPC_REMOVE_ALL);
137             if (r == -ENOTTY && !warned) {
138                 warned = true;
139                 warn_report("kernel does not support SGX_IOC_VEPC_REMOVE_ALL");
140                 warn_report("SGX might operate incorrectly in the guest after reset");
141                 break;
142             } else if (r > 0) {
143                 /* SECS pages remain */
144                 failures++;
145                 if (i == 1) {
146                     error_report("cannot reset vEPC section %d", j);
147                 }
148             }
149         }
150         if (!failures) {
151             break;
152         }
153      }
154 }
155 
156 SGXInfo *qmp_query_sgx_capabilities(Error **errp)
157 {
158     SGXInfo *info = NULL;
159     uint32_t eax, ebx, ecx, edx;
160 
161     int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR);
162     if (fd < 0) {
163         error_setg(errp, "SGX is not enabled in KVM");
164         return NULL;
165     }
166 
167     info = g_new0(SGXInfo, 1);
168     host_cpuid(0x7, 0, &eax, &ebx, &ecx, &edx);
169 
170     info->sgx = ebx & (1U << 2) ? true : false;
171     info->flc = ecx & (1U << 30) ? true : false;
172 
173     host_cpuid(0x12, 0, &eax, &ebx, &ecx, &edx);
174     info->sgx1 = eax & (1U << 0) ? true : false;
175     info->sgx2 = eax & (1U << 1) ? true : false;
176 
177     info->sections = sgx_calc_host_epc_sections();
178 
179     close(fd);
180 
181     return info;
182 }
183 
184 static SGXEPCSectionList *sgx_get_epc_sections_list(void)
185 {
186     GSList *device_list = sgx_epc_get_device_list();
187     SGXEPCSectionList *head = NULL, **tail = &head;
188     SGXEPCSection *section;
189 
190     for (; device_list; device_list = device_list->next) {
191         DeviceState *dev = device_list->data;
192         Object *obj = OBJECT(dev);
193 
194         section = g_new0(SGXEPCSection, 1);
195         section->node = object_property_get_uint(obj, SGX_EPC_NUMA_NODE_PROP,
196                                                  &error_abort);
197         section->size = object_property_get_uint(obj, SGX_EPC_SIZE_PROP,
198                                                  &error_abort);
199         QAPI_LIST_APPEND(tail, section);
200     }
201     g_slist_free(device_list);
202 
203     return head;
204 }
205 
206 SGXInfo *qmp_query_sgx(Error **errp)
207 {
208     SGXInfo *info = NULL;
209     X86MachineState *x86ms;
210     PCMachineState *pcms =
211         (PCMachineState *)object_dynamic_cast(qdev_get_machine(),
212                                               TYPE_PC_MACHINE);
213     if (!pcms) {
214         error_setg(errp, "SGX is only supported on PC machines");
215         return NULL;
216     }
217 
218     x86ms = X86_MACHINE(pcms);
219     if (!x86ms->sgx_epc_list) {
220         error_setg(errp, "No EPC regions defined, SGX not available");
221         return NULL;
222     }
223 
224     info = g_new0(SGXInfo, 1);
225 
226     info->sgx = true;
227     info->sgx1 = true;
228     info->sgx2 = true;
229     info->flc = true;
230     info->sections = sgx_get_epc_sections_list();
231 
232     return info;
233 }
234 
235 void hmp_info_sgx(Monitor *mon, const QDict *qdict)
236 {
237     Error *err = NULL;
238     SGXEPCSectionList *section_list, *section;
239     g_autoptr(SGXInfo) info = qmp_query_sgx(&err);
240     uint64_t size = 0;
241 
242     if (err) {
243         error_report_err(err);
244         return;
245     }
246     monitor_printf(mon, "SGX support: %s\n",
247                    info->sgx ? "enabled" : "disabled");
248     monitor_printf(mon, "SGX1 support: %s\n",
249                    info->sgx1 ? "enabled" : "disabled");
250     monitor_printf(mon, "SGX2 support: %s\n",
251                    info->sgx2 ? "enabled" : "disabled");
252     monitor_printf(mon, "FLC support: %s\n",
253                    info->flc ? "enabled" : "disabled");
254 
255     section_list = info->sections;
256     for (section = section_list; section; section = section->next) {
257         monitor_printf(mon, "NUMA node #%" PRId64 ": ",
258                        section->value->node);
259         monitor_printf(mon, "size=%" PRIu64 "\n",
260                        section->value->size);
261         size += section->value->size;
262     }
263     monitor_printf(mon, "total size=%" PRIu64 "\n",
264                    size);
265 }
266 
267 bool sgx_epc_get_section(int section_nr, uint64_t *addr, uint64_t *size)
268 {
269     PCMachineState *pcms = PC_MACHINE(qdev_get_machine());
270     SGXEPCDevice *epc;
271 
272     if (pcms->sgx_epc.size == 0 || pcms->sgx_epc.nr_sections <= section_nr) {
273         return true;
274     }
275 
276     epc = pcms->sgx_epc.sections[section_nr];
277 
278     *addr = epc->addr;
279     *size = memory_device_get_region_size(MEMORY_DEVICE(epc), &error_fatal);
280 
281     return false;
282 }
283 
284 void pc_machine_init_sgx_epc(PCMachineState *pcms)
285 {
286     SGXEPCState *sgx_epc = &pcms->sgx_epc;
287     X86MachineState *x86ms = X86_MACHINE(pcms);
288     SgxEPCList *list = NULL;
289 
290     memset(sgx_epc, 0, sizeof(SGXEPCState));
291     if (!x86ms->sgx_epc_list) {
292         return;
293     }
294 
295     sgx_epc->base = x86ms->above_4g_mem_start + x86ms->above_4g_mem_size;
296 
297     memory_region_init(&sgx_epc->mr, OBJECT(pcms), "sgx-epc", UINT64_MAX);
298     memory_region_add_subregion(get_system_memory(), sgx_epc->base,
299                                 &sgx_epc->mr);
300 
301     for (list = x86ms->sgx_epc_list; list; list = list->next) {
302         DeviceState *dev = qdev_new(TYPE_SGX_EPC);
303 
304         /* set the memdev link with memory backend */
305         object_property_parse(OBJECT(dev), SGX_EPC_MEMDEV_PROP,
306                               list->value->memdev, &error_fatal);
307         /* set the numa node property for sgx epc object */
308         object_property_set_uint(OBJECT(dev), SGX_EPC_NUMA_NODE_PROP,
309                                  list->value->node, &error_fatal);
310         qdev_realize_and_unref(dev, NULL, &error_fatal);
311     }
312 
313     if ((sgx_epc->base + sgx_epc->size) < sgx_epc->base) {
314         error_report("Size of all 'sgx-epc' =0x%"PRIx64" causes EPC to wrap",
315                      sgx_epc->size);
316         exit(EXIT_FAILURE);
317     }
318 
319     memory_region_set_size(&sgx_epc->mr, sgx_epc->size);
320 
321     /* register the reset callback for sgx epc */
322     qemu_register_reset(sgx_epc_reset, NULL);
323 }
324