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 /* for gdb script dump-guest-memory.py */ 39 static VMCoreInfoState * volatile vmcoreinfo_state G_GNUC_UNUSED; 40 41 /* Given that this function is executing, there is at least one VMCOREINFO 42 * device. Check if there are several. 43 */ 44 if (!vmcoreinfo_find()) { 45 error_setg(errp, "at most one %s device is permitted", 46 VMCOREINFO_DEVICE); 47 return; 48 } 49 50 if (!fw_cfg || !fw_cfg->dma_enabled) { 51 error_setg(errp, "%s device requires fw_cfg with DMA", 52 VMCOREINFO_DEVICE); 53 return; 54 } 55 56 fw_cfg_add_file_callback(fw_cfg, "etc/vmcoreinfo", 57 NULL, fw_cfg_vmci_write, s, 58 &s->vmcoreinfo, sizeof(s->vmcoreinfo), false); 59 60 qemu_register_reset(vmcoreinfo_reset, dev); 61 vmcoreinfo_state = s; 62 } 63 64 static const VMStateDescription vmstate_vmcoreinfo = { 65 .name = "vmcoreinfo", 66 .version_id = 1, 67 .minimum_version_id = 1, 68 .fields = (VMStateField[]) { 69 VMSTATE_BOOL(has_vmcoreinfo, VMCoreInfoState), 70 VMSTATE_UINT16(vmcoreinfo.host_format, VMCoreInfoState), 71 VMSTATE_UINT16(vmcoreinfo.guest_format, VMCoreInfoState), 72 VMSTATE_UINT32(vmcoreinfo.size, VMCoreInfoState), 73 VMSTATE_UINT64(vmcoreinfo.paddr, VMCoreInfoState), 74 VMSTATE_END_OF_LIST() 75 }, 76 }; 77 78 static void vmcoreinfo_device_class_init(ObjectClass *klass, void *data) 79 { 80 DeviceClass *dc = DEVICE_CLASS(klass); 81 82 dc->vmsd = &vmstate_vmcoreinfo; 83 dc->realize = vmcoreinfo_realize; 84 dc->hotpluggable = false; 85 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 86 } 87 88 static const TypeInfo vmcoreinfo_device_info = { 89 .name = VMCOREINFO_DEVICE, 90 .parent = TYPE_DEVICE, 91 .instance_size = sizeof(VMCoreInfoState), 92 .class_init = vmcoreinfo_device_class_init, 93 }; 94 95 static void vmcoreinfo_register_types(void) 96 { 97 type_register_static(&vmcoreinfo_device_info); 98 } 99 100 type_init(vmcoreinfo_register_types) 101