1 /* 2 * Virtual Machine coreinfo device 3 * 4 * Copyright (C) 2017 Red Hat, Inc. 5 * 6 * Authors: Marc-André Lureau <marcandre.lureau@redhat.com> 7 * 8 * This work is licensed under the terms of the GNU GPL, version 2 or later. 9 * See the COPYING file in the top-level directory. 10 * 11 */ 12 #include "qemu/osdep.h" 13 #include "qapi/error.h" 14 #include "hw/nvram/fw_cfg.h" 15 #include "hw/misc/vmcoreinfo.h" 16 17 static void fw_cfg_vmci_write(void *dev, off_t offset, size_t len) 18 { 19 VMCoreInfoState *s = VMCOREINFO(dev); 20 21 s->has_vmcoreinfo = offset == 0 && len == sizeof(s->vmcoreinfo) 22 && s->vmcoreinfo.guest_format != VMCOREINFO_FORMAT_NONE; 23 } 24 25 static void vmcoreinfo_reset(void *dev) 26 { 27 VMCoreInfoState *s = VMCOREINFO(dev); 28 29 s->has_vmcoreinfo = false; 30 memset(&s->vmcoreinfo, 0, sizeof(s->vmcoreinfo)); 31 s->vmcoreinfo.host_format = cpu_to_le16(VMCOREINFO_FORMAT_ELF); 32 } 33 34 static void vmcoreinfo_realize(DeviceState *dev, Error **errp) 35 { 36 VMCoreInfoState *s = VMCOREINFO(dev); 37 FWCfgState *fw_cfg = fw_cfg_find(); 38 39 /* Given that this function is executing, there is at least one VMCOREINFO 40 * device. Check if there are several. 41 */ 42 if (!vmcoreinfo_find()) { 43 error_setg(errp, "at most one %s device is permitted", 44 VMCOREINFO_DEVICE); 45 return; 46 } 47 48 if (!fw_cfg || !fw_cfg->dma_enabled) { 49 error_setg(errp, "%s device requires fw_cfg with DMA", 50 VMCOREINFO_DEVICE); 51 return; 52 } 53 54 fw_cfg_add_file_callback(fw_cfg, "etc/vmcoreinfo", 55 NULL, fw_cfg_vmci_write, s, 56 &s->vmcoreinfo, sizeof(s->vmcoreinfo), false); 57 58 qemu_register_reset(vmcoreinfo_reset, dev); 59 } 60 61 static const VMStateDescription vmstate_vmcoreinfo = { 62 .name = "vmcoreinfo", 63 .version_id = 1, 64 .minimum_version_id = 1, 65 .fields = (VMStateField[]) { 66 VMSTATE_BOOL(has_vmcoreinfo, VMCoreInfoState), 67 VMSTATE_UINT16(vmcoreinfo.host_format, VMCoreInfoState), 68 VMSTATE_UINT16(vmcoreinfo.guest_format, VMCoreInfoState), 69 VMSTATE_UINT32(vmcoreinfo.size, VMCoreInfoState), 70 VMSTATE_UINT64(vmcoreinfo.paddr, VMCoreInfoState), 71 VMSTATE_END_OF_LIST() 72 }, 73 }; 74 75 static void vmcoreinfo_device_class_init(ObjectClass *klass, void *data) 76 { 77 DeviceClass *dc = DEVICE_CLASS(klass); 78 79 dc->vmsd = &vmstate_vmcoreinfo; 80 dc->realize = vmcoreinfo_realize; 81 dc->hotpluggable = false; 82 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 83 } 84 85 static const TypeInfo vmcoreinfo_device_info = { 86 .name = VMCOREINFO_DEVICE, 87 .parent = TYPE_DEVICE, 88 .instance_size = sizeof(VMCoreInfoState), 89 .class_init = vmcoreinfo_device_class_init, 90 }; 91 92 static void vmcoreinfo_register_types(void) 93 { 94 type_register_static(&vmcoreinfo_device_info); 95 } 96 97 type_init(vmcoreinfo_register_types) 98