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 "hw/misc/vmcoreinfo.h" 19 20 static void fw_cfg_vmci_write(void *dev, off_t offset, size_t len) 21 { 22 VMCoreInfoState *s = VMCOREINFO(dev); 23 24 s->has_vmcoreinfo = offset == 0 && len == sizeof(s->vmcoreinfo) 25 && s->vmcoreinfo.guest_format != FW_CFG_VMCOREINFO_FORMAT_NONE; 26 } 27 28 static void vmcoreinfo_reset(void *dev) 29 { 30 VMCoreInfoState *s = VMCOREINFO(dev); 31 32 s->has_vmcoreinfo = false; 33 memset(&s->vmcoreinfo, 0, sizeof(s->vmcoreinfo)); 34 s->vmcoreinfo.host_format = cpu_to_le16(FW_CFG_VMCOREINFO_FORMAT_ELF); 35 } 36 37 static void vmcoreinfo_realize(DeviceState *dev, Error **errp) 38 { 39 VMCoreInfoState *s = VMCOREINFO(dev); 40 FWCfgState *fw_cfg = fw_cfg_find(); 41 /* for gdb script dump-guest-memory.py */ 42 static VMCoreInfoState * volatile vmcoreinfo_state G_GNUC_UNUSED; 43 44 /* Given that this function is executing, there is at least one VMCOREINFO 45 * device. Check if there are several. 46 */ 47 if (!vmcoreinfo_find()) { 48 error_setg(errp, "at most one %s device is permitted", 49 VMCOREINFO_DEVICE); 50 return; 51 } 52 53 if (!fw_cfg || !fw_cfg->dma_enabled) { 54 error_setg(errp, "%s device requires fw_cfg with DMA", 55 VMCOREINFO_DEVICE); 56 return; 57 } 58 59 fw_cfg_add_file_callback(fw_cfg, FW_CFG_VMCOREINFO_FILENAME, 60 NULL, fw_cfg_vmci_write, s, 61 &s->vmcoreinfo, sizeof(s->vmcoreinfo), false); 62 63 qemu_register_reset(vmcoreinfo_reset, dev); 64 vmcoreinfo_state = s; 65 } 66 67 static const VMStateDescription vmstate_vmcoreinfo = { 68 .name = "vmcoreinfo", 69 .version_id = 1, 70 .minimum_version_id = 1, 71 .fields = (VMStateField[]) { 72 VMSTATE_BOOL(has_vmcoreinfo, VMCoreInfoState), 73 VMSTATE_UINT16(vmcoreinfo.host_format, VMCoreInfoState), 74 VMSTATE_UINT16(vmcoreinfo.guest_format, VMCoreInfoState), 75 VMSTATE_UINT32(vmcoreinfo.size, VMCoreInfoState), 76 VMSTATE_UINT64(vmcoreinfo.paddr, VMCoreInfoState), 77 VMSTATE_END_OF_LIST() 78 }, 79 }; 80 81 static void vmcoreinfo_device_class_init(ObjectClass *klass, void *data) 82 { 83 DeviceClass *dc = DEVICE_CLASS(klass); 84 85 dc->vmsd = &vmstate_vmcoreinfo; 86 dc->realize = vmcoreinfo_realize; 87 dc->hotpluggable = false; 88 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 89 } 90 91 static const TypeInfo vmcoreinfo_device_info = { 92 .name = VMCOREINFO_DEVICE, 93 .parent = TYPE_DEVICE, 94 .instance_size = sizeof(VMCoreInfoState), 95 .class_init = vmcoreinfo_device_class_init, 96 }; 97 98 static void vmcoreinfo_register_types(void) 99 { 100 type_register_static(&vmcoreinfo_device_info); 101 } 102 103 type_init(vmcoreinfo_register_types) 104