| 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 "system/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 *opaque, off_t offset, size_t len) |
| 22 | { |
| 23 | VMCoreInfoState *s = opaque; |
| 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_hold(Object *obj, ResetType type) |
| 30 | { |
| 31 | VMCoreInfoState *s = VMCOREINFO(obj); |
| 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 | TYPE_VMCOREINFO); |
| 51 | return; |
| 52 | } |
| 53 | |
| 54 | if (!fw_cfg || !fw_cfg->dma_enabled) { |
| 55 | error_setg(errp, "%s device requires fw_cfg with DMA", |
| 56 | TYPE_VMCOREINFO); |
| 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_resettable(OBJECT(s)); |
| 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 = (const 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, const void *data) |
| 87 | { |
| 88 | DeviceClass *dc = DEVICE_CLASS(klass); |
| 89 | ResettableClass *rc = RESETTABLE_CLASS(klass); |
| 90 | |
| 91 | dc->vmsd = &vmstate_vmcoreinfo; |
| 92 | dc->realize = vmcoreinfo_realize; |
| 93 | dc->hotpluggable = false; |
| 94 | set_bit(DEVICE_CATEGORY_MISC, dc->categories); |
| 95 | rc->phases.hold = vmcoreinfo_reset_hold; |
| 96 | } |
| 97 | |
| 98 | static const TypeInfo vmcoreinfo_types[] = { |
| 99 | { |
| 100 | .name = TYPE_VMCOREINFO, |
| 101 | .parent = TYPE_DEVICE, |
| 102 | .instance_size = sizeof(VMCoreInfoState), |
| 103 | .class_init = vmcoreinfo_device_class_init, |
| 104 | } |
| 105 | }; |
| 106 | |
| 107 | DEFINE_TYPES(vmcoreinfo_types) |