1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
33  * https://docs.microsoft.com/en-us/windows/win32/hyperv_v2/virtual-machine-generation-identifier ,
34  * https://azure.microsoft.com/en-us/blog/accessing-and-using-azure-vm-unique-id/
39  * - QEMU: https://bugzilla.redhat.com/show_bug.cgi?id=1118834
40  * - VMware/ESXi: https://kb.vmware.com/s/article/2032586
41 …* - Xen: https://github.com/xenserver/xen-4.5/blob/master/tools/firmware/hvmloader/acpi/dsdt.asl#L…
56 #include <contrib/dev/acpica/include/acpi.h>
58 #include <dev/acpica/acpivar.h>
59 #include <dev/random/random_harvestq.h>
60 #include <dev/vmgenc/vmgenc_acpi.h>
73 MODULE_PNP_INFO("Z:_CID", acpi, vmgenc, vmgenc_ids, nitems(vmgenc_ids) - 1);
88 		    sizeof(((struct harvest_event *)0)->he_entropy));  in vmgenc_harvest_all()
91 		sz -= nbytes;  in vmgenc_harvest_all()
100 	device_t dev;  in vmgenc_status_changed()  local
102 	dev = context;  in vmgenc_status_changed()
103 	sc = device_get_softc(dev);  in vmgenc_status_changed()
106 	memcpy(guid, __DEVOLATILE(void *, sc->vmg_pguid), sizeof(guid));  in vmgenc_status_changed()
107 	if (memcmp(guid, sc->vmg_cache_guid, GUID_BYTES) == 0)  in vmgenc_status_changed()
111 	memcpy(sc->vmg_cache_guid, guid, GUID_BYTES);  in vmgenc_status_changed()
113 	vmgenc_harvest_all(sc->vmg_cache_guid, sizeof(sc->vmg_cache_guid));  in vmgenc_status_changed()
116 	acpi_UserNotify("VMGenerationCounter", acpi_get_handle(dev), 0);  in vmgenc_status_changed()
122 	device_t dev;  in vmgenc_notify()  local
124 	dev = context;  in vmgenc_notify()
131 		AcpiOsExecute(OSL_NOTIFY_HANDLER, vmgenc_status_changed, dev);  in vmgenc_notify()
134 		device_printf(dev, "unknown notify %#x\n", notify);  in vmgenc_notify()
140 vmgenc_probe(device_t dev)  in vmgenc_probe()  argument
146 	rv = ACPI_ID_PROBE(device_get_parent(dev), dev,  in vmgenc_probe()
149 		device_set_desc(dev, "VM Generation Counter");  in vmgenc_probe()
154 vmgenc_acpi_getname(ACPI_HANDLE handle, char data[static 256])  in vmgenc_acpi_getname()  argument
161     if (ACPI_SUCCESS(AcpiGetName(handle, ACPI_FULL_PATHNAME, &buf)))  in vmgenc_acpi_getname()
167 acpi_GetPackedUINT64(device_t dev, ACPI_HANDLE handle, char *path,  in acpi_GetPackedUINT64()  argument
177 	status = AcpiEvaluateObject(handle, path, NULL, &buf);  in acpi_GetPackedUINT64()
179 		device_printf(dev, "%s(%s::%s()): %s\n", __func__,  in acpi_GetPackedUINT64()
180 		    vmgenc_acpi_getname(handle, hpath), path,  in acpi_GetPackedUINT64()
185 		device_printf(dev, "%s(%s::%s()): Wrong type %#x\n", __func__,  in acpi_GetPackedUINT64()
186 		    vmgenc_acpi_getname(handle, hpath), path,  in acpi_GetPackedUINT64()
191 		device_printf(dev, "%s(%s::%s()): Wrong number of results %u\n",  in acpi_GetPackedUINT64()
192 		    __func__, vmgenc_acpi_getname(handle, hpath), path,  in acpi_GetPackedUINT64()
198 		device_printf(dev, "%s(%s::%s()): Wrong type results %#x, %#x\n",  in acpi_GetPackedUINT64()
199 		    __func__, vmgenc_acpi_getname(handle, hpath), path,  in acpi_GetPackedUINT64()
214 vmgenc_attach(device_t dev)  in vmgenc_attach()  argument
221 	h = acpi_get_handle(dev);  in vmgenc_attach()
222 	sc = device_get_softc(dev);  in vmgenc_attach()
224 	error = acpi_GetPackedUINT64(dev, h, "ADDR", &guid_physaddr);  in vmgenc_attach()
228 	SYSCTL_ADD_OPAQUE(device_get_sysctl_ctx(dev),  in vmgenc_attach()
229 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "guid",  in vmgenc_attach()
230 	    CTLFLAG_RD, sc->vmg_cache_guid, GUID_BYTES, "",  in vmgenc_attach()
231 	    "latest cached VM generation counter (128-bit UUID)");  in vmgenc_attach()
233 	sc->vmg_pguid = AcpiOsMapMemory(guid_physaddr, GUID_BYTES);  in vmgenc_attach()
234 	memcpy(sc->vmg_cache_guid, __DEVOLATILE(void *, sc->vmg_pguid),  in vmgenc_attach()
235 	    sizeof(sc->vmg_cache_guid));  in vmgenc_attach()
238 	vmgenc_harvest_all(sc->vmg_cache_guid, sizeof(sc->vmg_cache_guid));  in vmgenc_attach()
240 	AcpiInstallNotifyHandler(h, ACPI_DEVICE_NOTIFY, vmgenc_notify, dev);  in vmgenc_attach()