1 /* 2 * Memory Device Interface 3 * 4 * Copyright (c) 2018 Red Hat, Inc. 5 * 6 * Authors: 7 * David Hildenbrand <david@redhat.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or later. 10 * See the COPYING file in the top-level directory. 11 */ 12 13 #ifndef MEMORY_DEVICE_H 14 #define MEMORY_DEVICE_H 15 16 #include "qom/object.h" 17 #include "hw/qdev.h" 18 19 #define TYPE_MEMORY_DEVICE "memory-device" 20 21 #define MEMORY_DEVICE_CLASS(klass) \ 22 OBJECT_CLASS_CHECK(MemoryDeviceClass, (klass), TYPE_MEMORY_DEVICE) 23 #define MEMORY_DEVICE_GET_CLASS(obj) \ 24 OBJECT_GET_CLASS(MemoryDeviceClass, (obj), TYPE_MEMORY_DEVICE) 25 #define MEMORY_DEVICE(obj) \ 26 INTERFACE_CHECK(MemoryDeviceState, (obj), TYPE_MEMORY_DEVICE) 27 28 typedef struct MemoryDeviceState { 29 Object parent_obj; 30 } MemoryDeviceState; 31 32 /** 33 * MemoryDeviceClass: 34 * 35 * All memory devices need to implement TYPE_MEMORY_DEVICE as an interface. 36 * 37 * A memory device is a device that owns a memory region which is 38 * mapped into guest physical address space at a certain address. The 39 * address in guest physical memory can either be specified explicitly 40 * or get assigned automatically. 41 * 42 * Conceptually, memory devices only span one memory region. If multiple 43 * successive memory regions are used, a covering memory region has to 44 * be provided. Scattered memory regions are not supported for single 45 * devices. 46 */ 47 typedef struct MemoryDeviceClass { 48 /* private */ 49 InterfaceClass parent_class; 50 51 /* 52 * Return the address of the memory device in guest physical memory. 53 * 54 * Called when (un)plugging a memory device or when iterating over 55 * all memory devices mapped into guest physical address space. 56 * 57 * If "0" is returned, no address has been specified by the user and 58 * no address has been assigned to this memory device yet. 59 */ 60 uint64_t (*get_addr)(const MemoryDeviceState *md); 61 62 /* 63 * Set the address of the memory device in guest physical memory. 64 * 65 * Called when plugging the memory device to configure the determined 66 * address in guest physical memory. 67 */ 68 void (*set_addr)(MemoryDeviceState *md, uint64_t addr, Error **errp); 69 70 /* 71 * Return the amount of memory provided by the memory device currently 72 * usable ("plugged") by the VM. 73 * 74 * Called when calculating the total amount of ram available to the 75 * VM (e.g. to report memory stats to the user). 76 * 77 * This is helpful for devices that dynamically manage the amount of 78 * memory accessible by the guest via the reserved memory region. For 79 * most devices, this corresponds to the size of the memory region. 80 */ 81 uint64_t (*get_plugged_size)(const MemoryDeviceState *md, Error **errp); 82 83 /* 84 * Return the memory region of the memory device. 85 * 86 * Called when (un)plugging the memory device, to (un)map the 87 * memory region in guest physical memory, but also to detect the 88 * required alignment during address assignment or when the size of the 89 * memory region is required. 90 */ 91 MemoryRegion *(*get_memory_region)(MemoryDeviceState *md, Error **errp); 92 93 /* 94 * Translate the memory device into #MemoryDeviceInfo. 95 */ 96 void (*fill_device_info)(const MemoryDeviceState *md, 97 MemoryDeviceInfo *info); 98 } MemoryDeviceClass; 99 100 MemoryDeviceInfoList *qmp_memory_device_list(void); 101 uint64_t get_plugged_memory_size(void); 102 void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms, 103 const uint64_t *legacy_align, Error **errp); 104 void memory_device_plug(MemoryDeviceState *md, MachineState *ms); 105 void memory_device_unplug(MemoryDeviceState *md, MachineState *ms); 106 uint64_t memory_device_get_region_size(const MemoryDeviceState *md, 107 Error **errp); 108 109 #endif 110