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 "hw/qdev-core.h" 17 #include "qapi/qapi-types-machine.h" 18 #include "qom/object.h" 19 20 #define TYPE_MEMORY_DEVICE "memory-device" 21 22 typedef struct MemoryDeviceClass MemoryDeviceClass; 23 DECLARE_CLASS_CHECKERS(MemoryDeviceClass, MEMORY_DEVICE, 24 TYPE_MEMORY_DEVICE) 25 #define MEMORY_DEVICE(obj) \ 26 INTERFACE_CHECK(MemoryDeviceState, (obj), TYPE_MEMORY_DEVICE) 27 28 typedef struct MemoryDeviceState MemoryDeviceState; 29 30 /** 31 * MemoryDeviceClass: 32 * 33 * All memory devices need to implement TYPE_MEMORY_DEVICE as an interface. 34 * 35 * A memory device is a device that owns a memory region which is 36 * mapped into guest physical address space at a certain address. The 37 * address in guest physical memory can either be specified explicitly 38 * or get assigned automatically. 39 * 40 * Conceptually, memory devices only span one memory region. If multiple 41 * successive memory regions are used, a covering memory region has to 42 * be provided. Scattered memory regions are not supported for single 43 * devices. 44 */ 45 struct MemoryDeviceClass { 46 /* private */ 47 InterfaceClass parent_class; 48 49 /* 50 * Return the address of the memory device in guest physical memory. 51 * 52 * Called when (un)plugging a memory device or when iterating over 53 * all memory devices mapped into guest physical address space. 54 * 55 * If "0" is returned, no address has been specified by the user and 56 * no address has been assigned to this memory device yet. 57 */ 58 uint64_t (*get_addr)(const MemoryDeviceState *md); 59 60 /* 61 * Set the address of the memory device in guest physical memory. 62 * 63 * Called when plugging the memory device to configure the determined 64 * address in guest physical memory. 65 */ 66 void (*set_addr)(MemoryDeviceState *md, uint64_t addr, Error **errp); 67 68 /* 69 * Return the amount of memory provided by the memory device currently 70 * usable ("plugged") by the VM. 71 * 72 * Called when calculating the total amount of ram available to the 73 * VM (e.g. to report memory stats to the user). 74 * 75 * This is helpful for devices that dynamically manage the amount of 76 * memory accessible by the guest via the reserved memory region. For 77 * most devices, this corresponds to the size of the memory region. 78 */ 79 uint64_t (*get_plugged_size)(const MemoryDeviceState *md, Error **errp); 80 81 /* 82 * Return the memory region of the memory device. 83 * 84 * Called when (un)plugging the memory device, to (un)map the 85 * memory region in guest physical memory, but also to detect the 86 * required alignment during address assignment or when the size of the 87 * memory region is required. 88 */ 89 MemoryRegion *(*get_memory_region)(MemoryDeviceState *md, Error **errp); 90 91 /* 92 * Optional: Return the desired minimum alignment of the device in guest 93 * physical address space. The final alignment is computed based on this 94 * alignment and the alignment requirements of the memory region. 95 * 96 * Called when plugging the memory device to detect the required alignment 97 * during address assignment. 98 */ 99 uint64_t (*get_min_alignment)(const MemoryDeviceState *md); 100 101 /* 102 * Translate the memory device into #MemoryDeviceInfo. 103 */ 104 void (*fill_device_info)(const MemoryDeviceState *md, 105 MemoryDeviceInfo *info); 106 }; 107 108 MemoryDeviceInfoList *qmp_memory_device_list(void); 109 uint64_t get_plugged_memory_size(void); 110 void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms, 111 const uint64_t *legacy_align, Error **errp); 112 void memory_device_plug(MemoryDeviceState *md, MachineState *ms); 113 void memory_device_unplug(MemoryDeviceState *md, MachineState *ms); 114 uint64_t memory_device_get_region_size(const MemoryDeviceState *md, 115 Error **errp); 116 117 #endif 118