@@ -1356,19 +1356,56 @@
}
}
+##
+# @VirtioMEMDeviceInfo:
+#
+# VirtioMEMDevice state information
+#
+# @id: device's ID
+#
+# @memaddr: physical address in memory, where device is mapped
+#
+# @requested-size: the user requested size of the device
+#
+# @size: the (current) size of memory that the device provides
+#
+# @max-size: the maximum size of memory that the device can provide
+#
+# @block-size: the block size of memory that the device provides
+#
+# @node: NUMA node number where device is assigned to
+#
+# @memdev: memory backend linked with the region
+#
+# Since: 5.1
+##
+{ 'struct': 'VirtioMEMDeviceInfo',
+ 'data': { '*id': 'str',
+ 'memaddr': 'size',
+ 'requested-size': 'size',
+ 'size': 'size',
+ 'max-size': 'size',
+ 'block-size': 'size',
+ 'node': 'int',
+ 'memdev': 'str'
+ }
+}
+
##
# @MemoryDeviceInfo:
#
# Union containing information about a memory device
#
# nvdimm is included since 2.12. virtio-pmem is included since 4.1.
+# virtio-mem is included since 5.1.
#
# Since: 2.1
##
{ 'union': 'MemoryDeviceInfo',
'data': { 'dimm': 'PCDIMMDeviceInfo',
'nvdimm': 'PCDIMMDeviceInfo',
- 'virtio-pmem': 'VirtioPMEMDeviceInfo'
+ 'virtio-pmem': 'VirtioPMEMDeviceInfo',
+ 'virtio-mem': 'VirtioMEMDeviceInfo'
}
}
new file mode 100644
@@ -0,0 +1,78 @@
+/*
+ * Virtio MEM device
+ *
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Authors:
+ * David Hildenbrand <david@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef HW_VIRTIO_MEM_H
+#define HW_VIRTIO_MEM_H
+
+#include "standard-headers/linux/virtio_mem.h"
+#include "hw/virtio/virtio.h"
+#include "qapi/qapi-types-misc.h"
+#include "sysemu/hostmem.h"
+
+#define TYPE_VIRTIO_MEM "virtio-mem"
+
+#define VIRTIO_MEM(obj) \
+ OBJECT_CHECK(VirtIOMEM, (obj), TYPE_VIRTIO_MEM)
+#define VIRTIO_MEM_CLASS(oc) \
+ OBJECT_CLASS_CHECK(VirtIOMEMClass, (oc), TYPE_VIRTIO_MEM)
+#define VIRTIO_MEM_GET_CLASS(obj) \
+ OBJECT_GET_CLASS(VirtIOMEMClass, (obj), TYPE_VIRTIO_MEM)
+
+#define VIRTIO_MEM_MEMDEV_PROP "memdev"
+#define VIRTIO_MEM_NODE_PROP "node"
+#define VIRTIO_MEM_SIZE_PROP "size"
+#define VIRTIO_MEM_REQUESTED_SIZE_PROP "requested-size"
+#define VIRTIO_MEM_BLOCK_SIZE_PROP "block-size"
+#define VIRTIO_MEM_ADDR_PROP "memaddr"
+
+typedef struct VirtIOMEM {
+ VirtIODevice parent_obj;
+
+ /* guest -> host request queue */
+ VirtQueue *vq;
+
+ /* bitmap used to track unplugged memory */
+ int32_t bitmap_size;
+ unsigned long *bitmap;
+
+ /* assigned memory backend and memory region */
+ HostMemoryBackend *memdev;
+
+ /* NUMA node */
+ uint32_t node;
+
+ /* assigned address of the region in guest physical memory */
+ uint64_t addr;
+
+ /* usable region size (<= region_size) */
+ uint64_t usable_region_size;
+
+ /* actual size (how much the guest plugged) */
+ uint64_t size;
+
+ /* requested size */
+ uint64_t requested_size;
+
+ /* block size and alignment */
+ uint64_t block_size;
+} VirtIOMEM;
+
+typedef struct VirtIOMEMClass {
+ /* private */
+ VirtIODevice parent;
+
+ /* public */
+ void (*fill_device_info)(const VirtIOMEM *vmen, VirtioMEMDeviceInfo *vi);
+ MemoryRegion *(*get_memory_region)(VirtIOMEM *vmem, Error **errp);
+} VirtIOMEMClass;
+
+#endif
new file mode 100644
@@ -0,0 +1,724 @@
+/*
+ * Virtio MEM device
+ *
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Authors:
+ * David Hildenbrand <david@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "qemu/iov.h"
+#include "qemu/cutils.h"
+#include "qemu/error-report.h"
+#include "qemu/units.h"
+#include "sysemu/numa.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/reset.h"
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/virtio-access.h"
+#include "hw/virtio/virtio-mem.h"
+#include "qapi/error.h"
+#include "qapi/visitor.h"
+#include "exec/ram_addr.h"
+#include "migration/misc.h"
+#include "hw/boards.h"
+#include "hw/qdev-properties.h"
+#include "config-devices.h"
+
+/*
+ * Use QEMU_VMALLOC_ALIGN, so no THP will have to be split when unplugging
+ * memory (e.g., 2MB on x86_64).
+ */
+#define VIRTIO_MEM_MIN_BLOCK_SIZE QEMU_VMALLOC_ALIGN
+/*
+ * Size the usable region bigger than the requested size if possible. Esp.
+ * Linux guests will only add (aligned) memory blocks in case they fully
+ * fit into the usable region, but plug+online only a subset of the pages.
+ * The memory block size corresponds mostly to the section size.
+ *
+ * This allows e.g., to add 20MB with a section size of 128MB on x86_64, and
+ * a section size of 1GB on arm64 (as long as the start address is properly
+ * aligned, similar to ordinary DIMMs).
+ *
+ * We can change this at any time and maybe even make it configurable if
+ * necessary (as the section size can change). But it's more likely that the
+ * section size will rather get smaller and not bigger over time.
+ */
+#if defined(TARGET_X86_64) || defined(TARGET_I386)
+#define VIRTIO_MEM_USABLE_EXTENT (2 * (128 * MiB))
+#else
+#error VIRTIO_MEM_USABLE_EXTENT not defined
+#endif
+
+static bool virtio_mem_is_busy(void)
+{
+ /*
+ * Postcopy cannot handle concurrent discards and we don't want to migrate
+ * pages on-demand with stale content when plugging new blocks.
+ */
+ return migration_in_incoming_postcopy();
+}
+
+static bool virtio_mem_test_bitmap(VirtIOMEM *vmem, uint64_t start_gpa,
+ uint64_t size, bool plugged)
+{
+ const unsigned long first_bit = (start_gpa - vmem->addr) / vmem->block_size;
+ const unsigned long last_bit = first_bit + (size / vmem->block_size) - 1;
+ unsigned long found_bit;
+
+ /* We fake a shorter bitmap to avoid searching too far. */
+ if (plugged) {
+ found_bit = find_next_zero_bit(vmem->bitmap, last_bit + 1, first_bit);
+ } else {
+ found_bit = find_next_bit(vmem->bitmap, last_bit + 1, first_bit);
+ }
+ return found_bit > last_bit;
+}
+
+static void virtio_mem_set_bitmap(VirtIOMEM *vmem, uint64_t start_gpa,
+ uint64_t size, bool plugged)
+{
+ const unsigned long bit = (start_gpa - vmem->addr) / vmem->block_size;
+ const unsigned long nbits = size / vmem->block_size;
+
+ if (plugged) {
+ bitmap_set(vmem->bitmap, bit, nbits);
+ } else {
+ bitmap_clear(vmem->bitmap, bit, nbits);
+ }
+}
+
+static void virtio_mem_send_response(VirtIOMEM *vmem, VirtQueueElement *elem,
+ struct virtio_mem_resp *resp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(vmem);
+ VirtQueue *vq = vmem->vq;
+
+ iov_from_buf(elem->in_sg, elem->in_num, 0, resp, sizeof(*resp));
+
+ virtqueue_push(vq, elem, sizeof(*resp));
+ virtio_notify(vdev, vq);
+}
+
+static void virtio_mem_send_response_simple(VirtIOMEM *vmem,
+ VirtQueueElement *elem,
+ uint16_t type)
+{
+ struct virtio_mem_resp resp = {
+ .type = cpu_to_le16(type),
+ };
+
+ virtio_mem_send_response(vmem, elem, &resp);
+}
+
+static bool virtio_mem_valid_range(VirtIOMEM *vmem, uint64_t gpa, uint64_t size)
+{
+ if (!QEMU_IS_ALIGNED(gpa, vmem->block_size)) {
+ return false;
+ }
+ if (gpa + size < gpa || !size) {
+ return false;
+ }
+ if (gpa < vmem->addr || gpa >= vmem->addr + vmem->usable_region_size) {
+ return false;
+ }
+ if (gpa + size > vmem->addr + vmem->usable_region_size) {
+ return false;
+ }
+ return true;
+}
+
+static int virtio_mem_set_block_state(VirtIOMEM *vmem, uint64_t start_gpa,
+ uint64_t size, bool plug)
+{
+ const uint64_t offset = start_gpa - vmem->addr;
+ int ret;
+
+ if (virtio_mem_is_busy()) {
+ return -EBUSY;
+ }
+
+ if (!plug) {
+ ret = ram_block_discard_range(vmem->memdev->mr.ram_block, offset, size);
+ if (ret) {
+ error_report("Unexpected error discarding RAM: %s",
+ strerror(-ret));
+ return -EBUSY;
+ }
+ }
+ virtio_mem_set_bitmap(vmem, start_gpa, size, plug);
+ return 0;
+}
+
+static int virtio_mem_state_change_request(VirtIOMEM *vmem, uint64_t gpa,
+ uint16_t nb_blocks, bool plug)
+{
+ const uint64_t size = nb_blocks * vmem->block_size;
+ int ret;
+
+ if (!virtio_mem_valid_range(vmem, gpa, size)) {
+ return VIRTIO_MEM_RESP_ERROR;
+ }
+
+ if (plug && (vmem->size + size > vmem->requested_size)) {
+ return VIRTIO_MEM_RESP_NACK;
+ }
+
+ /* test if really all blocks are in the opposite state */
+ if (!virtio_mem_test_bitmap(vmem, gpa, size, !plug)) {
+ return VIRTIO_MEM_RESP_ERROR;
+ }
+
+ ret = virtio_mem_set_block_state(vmem, gpa, size, plug);
+ if (ret) {
+ return VIRTIO_MEM_RESP_BUSY;
+ }
+ if (plug) {
+ vmem->size += size;
+ } else {
+ vmem->size -= size;
+ }
+ return VIRTIO_MEM_RESP_ACK;
+}
+
+static void virtio_mem_plug_request(VirtIOMEM *vmem, VirtQueueElement *elem,
+ struct virtio_mem_req *req)
+{
+ const uint64_t gpa = le64_to_cpu(req->u.plug.addr);
+ const uint16_t nb_blocks = le16_to_cpu(req->u.plug.nb_blocks);
+ uint16_t type;
+
+ type = virtio_mem_state_change_request(vmem, gpa, nb_blocks, true);
+ virtio_mem_send_response_simple(vmem, elem, type);
+}
+
+static void virtio_mem_unplug_request(VirtIOMEM *vmem, VirtQueueElement *elem,
+ struct virtio_mem_req *req)
+{
+ const uint64_t gpa = le64_to_cpu(req->u.unplug.addr);
+ const uint16_t nb_blocks = le16_to_cpu(req->u.unplug.nb_blocks);
+ uint16_t type;
+
+ type = virtio_mem_state_change_request(vmem, gpa, nb_blocks, false);
+ virtio_mem_send_response_simple(vmem, elem, type);
+}
+
+static void virtio_mem_resize_usable_region(VirtIOMEM *vmem,
+ uint64_t requested_size,
+ bool can_shrink)
+{
+ uint64_t newsize = MIN(memory_region_size(&vmem->memdev->mr),
+ requested_size + VIRTIO_MEM_USABLE_EXTENT);
+
+ if (!requested_size) {
+ newsize = 0;
+ }
+
+ if (newsize < vmem->usable_region_size && !can_shrink) {
+ return;
+ }
+
+ vmem->usable_region_size = newsize;
+}
+
+static int virtio_mem_unplug_all(VirtIOMEM *vmem)
+{
+ RAMBlock *rb = vmem->memdev->mr.ram_block;
+ int ret;
+
+ if (virtio_mem_is_busy()) {
+ return -EBUSY;
+ }
+
+ ret = ram_block_discard_range(rb, 0, qemu_ram_get_used_length(rb));
+ if (ret) {
+ error_report("Unexpected error discarding RAM: %s", strerror(-ret));
+ return -EBUSY;
+ }
+ bitmap_clear(vmem->bitmap, 0, vmem->bitmap_size);
+ vmem->size = 0;
+
+ virtio_mem_resize_usable_region(vmem, vmem->requested_size, true);
+ return 0;
+}
+
+static void virtio_mem_unplug_all_request(VirtIOMEM *vmem,
+ VirtQueueElement *elem)
+{
+ if (virtio_mem_unplug_all(vmem)) {
+ virtio_mem_send_response_simple(vmem, elem, VIRTIO_MEM_RESP_BUSY);
+ } else {
+ virtio_mem_send_response_simple(vmem, elem, VIRTIO_MEM_RESP_ACK);
+ }
+}
+
+static void virtio_mem_state_request(VirtIOMEM *vmem, VirtQueueElement *elem,
+ struct virtio_mem_req *req)
+{
+ const uint16_t nb_blocks = le16_to_cpu(req->u.state.nb_blocks);
+ const uint64_t gpa = le64_to_cpu(req->u.state.addr);
+ const uint64_t size = nb_blocks * vmem->block_size;
+ struct virtio_mem_resp resp = {
+ .type = cpu_to_le16(VIRTIO_MEM_RESP_ACK),
+ };
+
+ if (!virtio_mem_valid_range(vmem, gpa, size)) {
+ virtio_mem_send_response_simple(vmem, elem, VIRTIO_MEM_RESP_ERROR);
+ return;
+ }
+
+ if (virtio_mem_test_bitmap(vmem, gpa, size, true)) {
+ resp.u.state.state = cpu_to_le16(VIRTIO_MEM_STATE_PLUGGED);
+ } else if (virtio_mem_test_bitmap(vmem, gpa, size, false)) {
+ resp.u.state.state = cpu_to_le16(VIRTIO_MEM_STATE_UNPLUGGED);
+ } else {
+ resp.u.state.state = cpu_to_le16(VIRTIO_MEM_STATE_MIXED);
+ }
+ virtio_mem_send_response(vmem, elem, &resp);
+}
+
+static void virtio_mem_handle_request(VirtIODevice *vdev, VirtQueue *vq)
+{
+ const int len = sizeof(struct virtio_mem_req);
+ VirtIOMEM *vmem = VIRTIO_MEM(vdev);
+ VirtQueueElement *elem;
+ struct virtio_mem_req req;
+ uint16_t type;
+
+ while (true) {
+ elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
+ if (!elem) {
+ return;
+ }
+
+ if (iov_to_buf(elem->out_sg, elem->out_num, 0, &req, len) < len) {
+ virtio_error(vdev, "virtio-mem protocol violation: invalid request"
+ " size: %d", len);
+ g_free(elem);
+ return;
+ }
+
+ if (iov_size(elem->in_sg, elem->in_num) <
+ sizeof(struct virtio_mem_resp)) {
+ virtio_error(vdev, "virtio-mem protocol violation: not enough space"
+ " for response: %zu",
+ iov_size(elem->in_sg, elem->in_num));
+ g_free(elem);
+ return;
+ }
+
+ type = le16_to_cpu(req.type);
+ switch (type) {
+ case VIRTIO_MEM_REQ_PLUG:
+ virtio_mem_plug_request(vmem, elem, &req);
+ break;
+ case VIRTIO_MEM_REQ_UNPLUG:
+ virtio_mem_unplug_request(vmem, elem, &req);
+ break;
+ case VIRTIO_MEM_REQ_UNPLUG_ALL:
+ virtio_mem_unplug_all_request(vmem, elem);
+ break;
+ case VIRTIO_MEM_REQ_STATE:
+ virtio_mem_state_request(vmem, elem, &req);
+ break;
+ default:
+ virtio_error(vdev, "virtio-mem protocol violation: unknown request"
+ " type: %d", type);
+ g_free(elem);
+ return;
+ }
+
+ g_free(elem);
+ }
+}
+
+static void virtio_mem_get_config(VirtIODevice *vdev, uint8_t *config_data)
+{
+ VirtIOMEM *vmem = VIRTIO_MEM(vdev);
+ struct virtio_mem_config *config = (void *) config_data;
+
+ config->block_size = cpu_to_le64(vmem->block_size);
+ config->node_id = cpu_to_le16(vmem->node);
+ config->requested_size = cpu_to_le64(vmem->requested_size);
+ config->plugged_size = cpu_to_le64(vmem->size);
+ config->addr = cpu_to_le64(vmem->addr);
+ config->region_size = cpu_to_le64(memory_region_size(&vmem->memdev->mr));
+ config->usable_region_size = cpu_to_le64(vmem->usable_region_size);
+}
+
+static uint64_t virtio_mem_get_features(VirtIODevice *vdev, uint64_t features,
+ Error **errp)
+{
+ MachineState *ms = MACHINE(qdev_get_machine());
+
+ if (ms->numa_state) {
+#if defined(CONFIG_ACPI)
+ virtio_add_feature(&features, VIRTIO_MEM_F_ACPI_PXM);
+#endif
+ }
+ return features;
+}
+
+static void virtio_mem_system_reset(void *opaque)
+{
+ VirtIOMEM *vmem = VIRTIO_MEM(opaque);
+
+ /*
+ * During usual resets, we will unplug all memory and shrink the usable
+ * region size. This is, however, not possible in all scenarios. Then,
+ * the guest has to deal with this manually (VIRTIO_MEM_REQ_UNPLUG_ALL).
+ */
+ virtio_mem_unplug_all(vmem);
+}
+
+static void virtio_mem_device_realize(DeviceState *dev, Error **errp)
+{
+ MachineState *ms = MACHINE(qdev_get_machine());
+ int nb_numa_nodes = ms->numa_state ? ms->numa_state->num_nodes : 0;
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtIOMEM *vmem = VIRTIO_MEM(dev);
+ uint64_t page_size;
+ RAMBlock *rb;
+ int ret;
+
+ if (!vmem->memdev) {
+ error_setg(errp, "'%s' property is not set", VIRTIO_MEM_MEMDEV_PROP);
+ return;
+ } else if (host_memory_backend_is_mapped(vmem->memdev)) {
+ char *path = object_get_canonical_path_component(OBJECT(vmem->memdev));
+
+ error_setg(errp, "'%s' property specifies a busy memdev: %s",
+ VIRTIO_MEM_MEMDEV_PROP, path);
+ g_free(path);
+ return;
+ } else if (!memory_region_is_ram(&vmem->memdev->mr) ||
+ memory_region_is_rom(&vmem->memdev->mr) ||
+ !vmem->memdev->mr.ram_block) {
+ error_setg(errp, "'%s' property specifies an unsupported memdev",
+ VIRTIO_MEM_MEMDEV_PROP);
+ return;
+ }
+
+ if ((nb_numa_nodes && vmem->node >= nb_numa_nodes) ||
+ (!nb_numa_nodes && vmem->node)) {
+ error_setg(errp, "'%s' property has value '%" PRIu32 "', which exceeds"
+ "the number of numa nodes: %d", VIRTIO_MEM_NODE_PROP,
+ vmem->node, nb_numa_nodes ? nb_numa_nodes : 1);
+ return;
+ }
+
+ if (enable_mlock) {
+ error_setg(errp, "Incompatible with mlock");
+ return;
+ }
+
+ rb = vmem->memdev->mr.ram_block;
+ page_size = qemu_ram_pagesize(rb);
+
+ if (vmem->block_size < page_size) {
+ error_setg(errp, "'%s' property has to be at least the page size (0x%"
+ PRIx64 ")", VIRTIO_MEM_BLOCK_SIZE_PROP, page_size);
+ return;
+ } else if (!QEMU_IS_ALIGNED(vmem->requested_size, vmem->block_size)) {
+ error_setg(errp, "'%s' property has to be multiples of '%s' (0x%" PRIx64
+ ")", VIRTIO_MEM_REQUESTED_SIZE_PROP,
+ VIRTIO_MEM_BLOCK_SIZE_PROP, vmem->block_size);
+ return;
+ } else if (!QEMU_IS_ALIGNED(memory_region_size(&vmem->memdev->mr),
+ vmem->block_size)) {
+ error_setg(errp, "'%s' property memdev size has to be multiples of"
+ "'%s' (0x%" PRIx64 ")", VIRTIO_MEM_MEMDEV_PROP,
+ VIRTIO_MEM_BLOCK_SIZE_PROP, vmem->block_size);
+ return;
+ }
+
+ if (ram_block_discard_require(true)) {
+ error_setg(errp, "Discarding RAM is disabled");
+ return;
+ }
+
+ ret = ram_block_discard_range(rb, 0, qemu_ram_get_used_length(rb));
+ if (ret) {
+ error_setg_errno(errp, -ret, "Unexpected error discarding RAM");
+ ram_block_discard_require(false);
+ return;
+ }
+
+ virtio_mem_resize_usable_region(vmem, vmem->requested_size, true);
+
+ vmem->bitmap_size = memory_region_size(&vmem->memdev->mr) /
+ vmem->block_size;
+ vmem->bitmap = bitmap_new(vmem->bitmap_size);
+
+ virtio_init(vdev, TYPE_VIRTIO_MEM, VIRTIO_ID_MEM,
+ sizeof(struct virtio_mem_config));
+ vmem->vq = virtio_add_queue(vdev, 128, virtio_mem_handle_request);
+
+ host_memory_backend_set_mapped(vmem->memdev, true);
+ vmstate_register_ram(&vmem->memdev->mr, DEVICE(vmem));
+ qemu_register_reset(virtio_mem_system_reset, vmem);
+}
+
+static void virtio_mem_device_unrealize(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtIOMEM *vmem = VIRTIO_MEM(dev);
+
+ qemu_unregister_reset(virtio_mem_system_reset, vmem);
+ vmstate_unregister_ram(&vmem->memdev->mr, DEVICE(vmem));
+ host_memory_backend_set_mapped(vmem->memdev, false);
+ virtio_del_queue(vdev, 0);
+ virtio_cleanup(vdev);
+ g_free(vmem->bitmap);
+ ram_block_discard_require(false);
+}
+
+static int virtio_mem_restore_unplugged(VirtIOMEM *vmem)
+{
+ RAMBlock *rb = vmem->memdev->mr.ram_block;
+ unsigned long first_zero_bit, last_zero_bit;
+ uint64_t offset, length;
+ int ret;
+
+ /* Find consecutive unplugged blocks and discard the consecutive range. */
+ first_zero_bit = find_first_zero_bit(vmem->bitmap, vmem->bitmap_size);
+ while (first_zero_bit < vmem->bitmap_size) {
+ offset = first_zero_bit * vmem->block_size;
+ last_zero_bit = find_next_bit(vmem->bitmap, vmem->bitmap_size,
+ first_zero_bit + 1) - 1;
+ length = (last_zero_bit - first_zero_bit + 1) * vmem->block_size;
+
+ ret = ram_block_discard_range(rb, offset, length);
+ if (ret) {
+ error_report("Unexpected error discarding RAM: %s",
+ strerror(-ret));
+ return -EINVAL;
+ }
+ first_zero_bit = find_next_zero_bit(vmem->bitmap, vmem->bitmap_size,
+ last_zero_bit + 2);
+ }
+ return 0;
+}
+
+static int virtio_mem_post_load(void *opaque, int version_id)
+{
+ if (migration_in_incoming_postcopy()) {
+ return 0;
+ }
+
+ return virtio_mem_restore_unplugged(VIRTIO_MEM(opaque));
+}
+
+static const VMStateDescription vmstate_virtio_mem_device = {
+ .name = "virtio-mem-device",
+ .minimum_version_id = 1,
+ .version_id = 1,
+ .post_load = virtio_mem_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT64(usable_region_size, VirtIOMEM),
+ VMSTATE_UINT64(size, VirtIOMEM),
+ VMSTATE_UINT64(requested_size, VirtIOMEM),
+ VMSTATE_BITMAP(bitmap, VirtIOMEM, 0, bitmap_size),
+ VMSTATE_END_OF_LIST()
+ },
+};
+
+static const VMStateDescription vmstate_virtio_mem = {
+ .name = "virtio-mem",
+ .minimum_version_id = 1,
+ .version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_VIRTIO_DEVICE,
+ VMSTATE_END_OF_LIST()
+ },
+};
+
+static void virtio_mem_fill_device_info(const VirtIOMEM *vmem,
+ VirtioMEMDeviceInfo *vi)
+{
+ vi->memaddr = vmem->addr;
+ vi->node = vmem->node;
+ vi->requested_size = vmem->requested_size;
+ vi->size = vmem->size;
+ vi->max_size = memory_region_size(&vmem->memdev->mr);
+ vi->block_size = vmem->block_size;
+ vi->memdev = object_get_canonical_path(OBJECT(vmem->memdev));
+}
+
+static MemoryRegion *virtio_mem_get_memory_region(VirtIOMEM *vmem, Error **errp)
+{
+ if (!vmem->memdev) {
+ error_setg(errp, "'%s' property must be set", VIRTIO_MEM_MEMDEV_PROP);
+ return NULL;
+ }
+
+ return &vmem->memdev->mr;
+}
+
+static void virtio_mem_get_size(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ const VirtIOMEM *vmem = VIRTIO_MEM(obj);
+ uint64_t value = vmem->size;
+
+ visit_type_size(v, name, &value, errp);
+}
+
+static void virtio_mem_get_requested_size(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ const VirtIOMEM *vmem = VIRTIO_MEM(obj);
+ uint64_t value = vmem->requested_size;
+
+ visit_type_size(v, name, &value, errp);
+}
+
+static void virtio_mem_set_requested_size(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ VirtIOMEM *vmem = VIRTIO_MEM(obj);
+ Error *err = NULL;
+ uint64_t value;
+
+ visit_type_size(v, name, &value, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+
+ /*
+ * The block size and memory backend are not fixed until the device was
+ * realized. realize() will verify these properties then.
+ */
+ if (DEVICE(obj)->realized) {
+ if (!QEMU_IS_ALIGNED(value, vmem->block_size)) {
+ error_setg(errp, "'%s' has to be multiples of '%s' (0x%" PRIx64
+ ")", name, VIRTIO_MEM_BLOCK_SIZE_PROP,
+ vmem->block_size);
+ return;
+ } else if (value > memory_region_size(&vmem->memdev->mr)) {
+ error_setg(errp, "'%s' cannot exceed the memory backend size"
+ "(0x%" PRIx64 ")", name,
+ memory_region_size(&vmem->memdev->mr));
+ return;
+ }
+
+ if (value != vmem->requested_size) {
+ virtio_mem_resize_usable_region(vmem, value, false);
+ vmem->requested_size = value;
+ }
+ /*
+ * Trigger a config update so the guest gets notified. We trigger
+ * even if the size didn't change (especially helpful for debugging).
+ */
+ virtio_notify_config(VIRTIO_DEVICE(vmem));
+ } else {
+ vmem->requested_size = value;
+ }
+}
+
+static void virtio_mem_get_block_size(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ const VirtIOMEM *vmem = VIRTIO_MEM(obj);
+ uint64_t value = vmem->block_size;
+
+ visit_type_size(v, name, &value, errp);
+}
+
+static void virtio_mem_set_block_size(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ VirtIOMEM *vmem = VIRTIO_MEM(obj);
+ Error *err = NULL;
+ uint64_t value;
+
+ if (DEVICE(obj)->realized) {
+ error_setg(errp, "'%s' cannot be changed", name);
+ return;
+ }
+
+ visit_type_size(v, name, &value, &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+
+ if (value < VIRTIO_MEM_MIN_BLOCK_SIZE) {
+ error_setg(errp, "'%s' property has to be at least 0x%" PRIx32, name,
+ VIRTIO_MEM_MIN_BLOCK_SIZE);
+ return;
+ } else if (!is_power_of_2(value)) {
+ error_setg(errp, "'%s' property has to be a power of two", name);
+ return;
+ }
+ vmem->block_size = value;
+}
+
+static void virtio_mem_instance_init(Object *obj)
+{
+ VirtIOMEM *vmem = VIRTIO_MEM(obj);
+
+ vmem->block_size = VIRTIO_MEM_MIN_BLOCK_SIZE;
+
+ object_property_add(obj, VIRTIO_MEM_SIZE_PROP, "size", virtio_mem_get_size,
+ NULL, NULL, NULL);
+ object_property_add(obj, VIRTIO_MEM_REQUESTED_SIZE_PROP, "size",
+ virtio_mem_get_requested_size,
+ virtio_mem_set_requested_size, NULL, NULL);
+ object_property_add(obj, VIRTIO_MEM_BLOCK_SIZE_PROP, "size",
+ virtio_mem_get_block_size, virtio_mem_set_block_size,
+ NULL, NULL);
+}
+
+static Property virtio_mem_properties[] = {
+ DEFINE_PROP_UINT64(VIRTIO_MEM_ADDR_PROP, VirtIOMEM, addr, 0),
+ DEFINE_PROP_UINT32(VIRTIO_MEM_NODE_PROP, VirtIOMEM, node, 0),
+ DEFINE_PROP_LINK(VIRTIO_MEM_MEMDEV_PROP, VirtIOMEM, memdev,
+ TYPE_MEMORY_BACKEND, HostMemoryBackend *),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtio_mem_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+ VirtIOMEMClass *vmc = VIRTIO_MEM_CLASS(klass);
+
+ device_class_set_props(dc, virtio_mem_properties);
+ dc->vmsd = &vmstate_virtio_mem;
+
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+ vdc->realize = virtio_mem_device_realize;
+ vdc->unrealize = virtio_mem_device_unrealize;
+ vdc->get_config = virtio_mem_get_config;
+ vdc->get_features = virtio_mem_get_features;
+ vdc->vmsd = &vmstate_virtio_mem_device;
+
+ vmc->fill_device_info = virtio_mem_fill_device_info;
+ vmc->get_memory_region = virtio_mem_get_memory_region;
+}
+
+static const TypeInfo virtio_mem_info = {
+ .name = TYPE_VIRTIO_MEM,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VirtIOMEM),
+ .instance_init = virtio_mem_instance_init,
+ .class_init = virtio_mem_class_init,
+ .class_size = sizeof(VirtIOMEMClass),
+};
+
+static void virtio_register_types(void)
+{
+ type_register_static(&virtio_mem_info);
+}
+
+type_init(virtio_register_types)
@@ -47,3 +47,14 @@ config VIRTIO_PMEM
depends on VIRTIO
depends on VIRTIO_PMEM_SUPPORTED
select MEM_DEVICE
+
+config VIRTIO_MEM_SUPPORTED
+ bool
+
+config VIRTIO_MEM
+ bool
+ default y
+ depends on VIRTIO
+ depends on LINUX
+ depends on VIRTIO_MEM_SUPPORTED
+ select MEM_DEVICE
@@ -19,6 +19,7 @@ obj-$(call land,$(CONFIG_VHOST_USER_FS),$(CONFIG_VIRTIO_PCI)) += vhost-user-fs-p
obj-$(CONFIG_VIRTIO_IOMMU) += virtio-iommu.o
obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock-common.o vhost-vsock.o
obj-$(CONFIG_VHOST_USER_VSOCK) += vhost-vsock-common.o vhost-user-vsock.o
+obj-$(CONFIG_VIRTIO_MEM) += virtio-mem.o
ifeq ($(CONFIG_VIRTIO_PCI),y)
obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock-pci.o