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 13 #include "qemu/osdep.h" 14 #include "qapi/error.h" 15 #include "qemu/module.h" 16 #include "sysemu/reset.h" 17 #include "hw/nvram/fw_cfg.h" 18 #include "migration/vmstate.h" 19 #include "hw/misc/vmcoreinfo.h" 20 21 static void fw_cfg_vmci_write(void *dev, off_t offset, size_t len) 22 { 23 VMCoreInfoState *s = VMCOREINFO(dev); 24 25 s->has_vmcoreinfo = offset == 0 && len == sizeof(s->vmcoreinfo) 26 && s->vmcoreinfo.guest_format != FW_CFG_VMCOREINFO_FORMAT_NONE; 27 } 28 29 static void vmcoreinfo_reset(void *dev) 30 { 31 VMCoreInfoState *s = VMCOREINFO(dev); 32 33 s->has_vmcoreinfo = false; 34 memset(&s->vmcoreinfo, 0, sizeof(s->vmcoreinfo)); 35 s->vmcoreinfo.host_format = cpu_to_le16(FW_CFG_VMCOREINFO_FORMAT_ELF); 36 } 37 38 static void vmcoreinfo_realize(DeviceState *dev, Error **errp) 39 { 40 VMCoreInfoState *s = VMCOREINFO(dev); 41 FWCfgState *fw_cfg = fw_cfg_find(); 42 /* for gdb script dump-guest-memory.py */ 43 static VMCoreInfoState * volatile vmcoreinfo_state G_GNUC_UNUSED; 44 45 /* Given that this function is executing, there is at least one VMCOREINFO 46 * device. Check if there are several. 47 */ 48 if (!vmcoreinfo_find()) { 49 error_setg(errp, "at most one %s device is permitted", 50 VMCOREINFO_DEVICE); 51 return; 52 } 53 54 if (!fw_cfg || !fw_cfg->dma_enabled) { 55 error_setg(errp, "%s device requires fw_cfg with DMA", 56 VMCOREINFO_DEVICE); 57 return; 58 } 59 60 fw_cfg_add_file_callback(fw_cfg, FW_CFG_VMCOREINFO_FILENAME, 61 NULL, fw_cfg_vmci_write, s, 62 &s->vmcoreinfo, sizeof(s->vmcoreinfo), false); 63 64 /* 65 * This device requires to register a global reset because it is 66 * not plugged to a bus (which, as its QOM parent, would reset it). 67 */ 68 qemu_register_reset(vmcoreinfo_reset, dev); 69 vmcoreinfo_state = s; 70 } 71 72 static const VMStateDescription vmstate_vmcoreinfo = { 73 .name = "vmcoreinfo", 74 .version_id = 1, 75 .minimum_version_id = 1, 76 .fields = (VMStateField[]) { 77 VMSTATE_BOOL(has_vmcoreinfo, VMCoreInfoState), 78 VMSTATE_UINT16(vmcoreinfo.host_format, VMCoreInfoState), 79 VMSTATE_UINT16(vmcoreinfo.guest_format, VMCoreInfoState), 80 VMSTATE_UINT32(vmcoreinfo.size, VMCoreInfoState), 81 VMSTATE_UINT64(vmcoreinfo.paddr, VMCoreInfoState), 82 VMSTATE_END_OF_LIST() 83 }, 84 }; 85 86 static void vmcoreinfo_device_class_init(ObjectClass *klass, void *data) 87 { 88 DeviceClass *dc = DEVICE_CLASS(klass); 89 90 dc->vmsd = &vmstate_vmcoreinfo; 91 dc->realize = vmcoreinfo_realize; 92 dc->hotpluggable = false; 93 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 94 } 95 96 static const TypeInfo vmcoreinfo_device_info = { 97 .name = VMCOREINFO_DEVICE, 98 .parent = TYPE_DEVICE, 99 .instance_size = sizeof(VMCoreInfoState), 100 .class_init = vmcoreinfo_device_class_init, 101 }; 102 103 static void vmcoreinfo_register_types(void) 104 { 105 type_register_static(&vmcoreinfo_device_info); 106 } 107 108 type_init(vmcoreinfo_register_types) 109