object_get_canonical_path_component() returns a malloced copy of a property name on success, null on failure. 19 of its 25 callers immediately free the returned copy. Change object_get_canonical_path_component() to return the property name directly. Since modifying the name would be wrong, adjust the return type to const char *. Drop the free from the 19 callers become simpler, add the g_strdup() to the other six. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200714160202.3121879-4-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Li Qiang <liq3ea@gmail.com>
		
			
				
	
	
		
			872 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			872 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Virtio MEM device
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 *
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 * Copyright (C) 2020 Red Hat, Inc.
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 *
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 * Authors:
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 *  David Hildenbrand <david@redhat.com>
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2.
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 * See the COPYING file in the top-level directory.
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 */
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#include "qemu/osdep.h"
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#include "qemu-common.h"
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#include "qemu/iov.h"
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#include "qemu/cutils.h"
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#include "qemu/error-report.h"
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#include "qemu/units.h"
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#include "sysemu/numa.h"
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#include "sysemu/sysemu.h"
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#include "sysemu/reset.h"
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#include "hw/virtio/virtio.h"
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#include "hw/virtio/virtio-bus.h"
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#include "hw/virtio/virtio-access.h"
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#include "hw/virtio/virtio-mem.h"
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#include "qapi/error.h"
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#include "qapi/visitor.h"
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#include "exec/ram_addr.h"
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#include "migration/misc.h"
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#include "hw/boards.h"
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#include "hw/qdev-properties.h"
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#include "config-devices.h"
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#include "trace.h"
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/*
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 * Use QEMU_VMALLOC_ALIGN, so no THP will have to be split when unplugging
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 * memory (e.g., 2MB on x86_64).
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 */
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#define VIRTIO_MEM_MIN_BLOCK_SIZE QEMU_VMALLOC_ALIGN
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/*
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 * Size the usable region bigger than the requested size if possible. Esp.
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 * Linux guests will only add (aligned) memory blocks in case they fully
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 * fit into the usable region, but plug+online only a subset of the pages.
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 * The memory block size corresponds mostly to the section size.
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 *
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 * This allows e.g., to add 20MB with a section size of 128MB on x86_64, and
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 * a section size of 1GB on arm64 (as long as the start address is properly
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 * aligned, similar to ordinary DIMMs).
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 *
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 * We can change this at any time and maybe even make it configurable if
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 * necessary (as the section size can change). But it's more likely that the
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 * section size will rather get smaller and not bigger over time.
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 */
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#if defined(TARGET_X86_64) || defined(TARGET_I386)
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#define VIRTIO_MEM_USABLE_EXTENT (2 * (128 * MiB))
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#else
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#error VIRTIO_MEM_USABLE_EXTENT not defined
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#endif
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static bool virtio_mem_is_busy(void)
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{
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    /*
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     * Postcopy cannot handle concurrent discards and we don't want to migrate
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     * pages on-demand with stale content when plugging new blocks.
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     *
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     * For precopy, we don't want unplugged blocks in our migration stream, and
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     * when plugging new blocks, the page content might differ between source
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     * and destination (observable by the guest when not initializing pages
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     * after plugging them) until we're running on the destination (as we didn't
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     * migrate these blocks when they were unplugged).
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     */
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    return migration_in_incoming_postcopy() || !migration_is_idle();
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}
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static bool virtio_mem_test_bitmap(VirtIOMEM *vmem, uint64_t start_gpa,
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                                   uint64_t size, bool plugged)
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{
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    const unsigned long first_bit = (start_gpa - vmem->addr) / vmem->block_size;
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    const unsigned long last_bit = first_bit + (size / vmem->block_size) - 1;
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    unsigned long found_bit;
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    /* We fake a shorter bitmap to avoid searching too far. */
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    if (plugged) {
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        found_bit = find_next_zero_bit(vmem->bitmap, last_bit + 1, first_bit);
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    } else {
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        found_bit = find_next_bit(vmem->bitmap, last_bit + 1, first_bit);
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    }
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    return found_bit > last_bit;
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}
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static void virtio_mem_set_bitmap(VirtIOMEM *vmem, uint64_t start_gpa,
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                                  uint64_t size, bool plugged)
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{
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    const unsigned long bit = (start_gpa - vmem->addr) / vmem->block_size;
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    const unsigned long nbits = size / vmem->block_size;
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    if (plugged) {
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        bitmap_set(vmem->bitmap, bit, nbits);
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    } else {
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        bitmap_clear(vmem->bitmap, bit, nbits);
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    }
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}
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static void virtio_mem_send_response(VirtIOMEM *vmem, VirtQueueElement *elem,
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                                     struct virtio_mem_resp *resp)
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{
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    VirtIODevice *vdev = VIRTIO_DEVICE(vmem);
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    VirtQueue *vq = vmem->vq;
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    trace_virtio_mem_send_response(le16_to_cpu(resp->type));
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    iov_from_buf(elem->in_sg, elem->in_num, 0, resp, sizeof(*resp));
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    virtqueue_push(vq, elem, sizeof(*resp));
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    virtio_notify(vdev, vq);
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}
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static void virtio_mem_send_response_simple(VirtIOMEM *vmem,
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                                            VirtQueueElement *elem,
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                                            uint16_t type)
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{
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    struct virtio_mem_resp resp = {
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        .type = cpu_to_le16(type),
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    };
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    virtio_mem_send_response(vmem, elem, &resp);
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}
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static bool virtio_mem_valid_range(VirtIOMEM *vmem, uint64_t gpa, uint64_t size)
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{
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    if (!QEMU_IS_ALIGNED(gpa, vmem->block_size)) {
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        return false;
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    }
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    if (gpa + size < gpa || !size) {
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        return false;
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    }
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    if (gpa < vmem->addr || gpa >= vmem->addr + vmem->usable_region_size) {
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        return false;
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    }
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    if (gpa + size > vmem->addr + vmem->usable_region_size) {
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        return false;
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    }
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    return true;
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}
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static int virtio_mem_set_block_state(VirtIOMEM *vmem, uint64_t start_gpa,
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                                      uint64_t size, bool plug)
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{
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    const uint64_t offset = start_gpa - vmem->addr;
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    int ret;
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    if (virtio_mem_is_busy()) {
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        return -EBUSY;
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    }
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    if (!plug) {
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        ret = ram_block_discard_range(vmem->memdev->mr.ram_block, offset, size);
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        if (ret) {
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            error_report("Unexpected error discarding RAM: %s",
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                         strerror(-ret));
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            return -EBUSY;
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        }
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    }
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    virtio_mem_set_bitmap(vmem, start_gpa, size, plug);
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    return 0;
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}
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static int virtio_mem_state_change_request(VirtIOMEM *vmem, uint64_t gpa,
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                                           uint16_t nb_blocks, bool plug)
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{
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    const uint64_t size = nb_blocks * vmem->block_size;
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    int ret;
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    if (!virtio_mem_valid_range(vmem, gpa, size)) {
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        return VIRTIO_MEM_RESP_ERROR;
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    }
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    if (plug && (vmem->size + size > vmem->requested_size)) {
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        return VIRTIO_MEM_RESP_NACK;
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    }
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    /* test if really all blocks are in the opposite state */
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    if (!virtio_mem_test_bitmap(vmem, gpa, size, !plug)) {
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        return VIRTIO_MEM_RESP_ERROR;
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    }
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    ret = virtio_mem_set_block_state(vmem, gpa, size, plug);
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    if (ret) {
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        return VIRTIO_MEM_RESP_BUSY;
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    }
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    if (plug) {
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        vmem->size += size;
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    } else {
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        vmem->size -= size;
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    }
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    notifier_list_notify(&vmem->size_change_notifiers, &vmem->size);
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    return VIRTIO_MEM_RESP_ACK;
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}
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static void virtio_mem_plug_request(VirtIOMEM *vmem, VirtQueueElement *elem,
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                                    struct virtio_mem_req *req)
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{
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    const uint64_t gpa = le64_to_cpu(req->u.plug.addr);
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    const uint16_t nb_blocks = le16_to_cpu(req->u.plug.nb_blocks);
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    uint16_t type;
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    trace_virtio_mem_plug_request(gpa, nb_blocks);
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    type = virtio_mem_state_change_request(vmem, gpa, nb_blocks, true);
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    virtio_mem_send_response_simple(vmem, elem, type);
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}
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static void virtio_mem_unplug_request(VirtIOMEM *vmem, VirtQueueElement *elem,
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                                      struct virtio_mem_req *req)
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{
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    const uint64_t gpa = le64_to_cpu(req->u.unplug.addr);
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    const uint16_t nb_blocks = le16_to_cpu(req->u.unplug.nb_blocks);
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    uint16_t type;
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    trace_virtio_mem_unplug_request(gpa, nb_blocks);
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    type = virtio_mem_state_change_request(vmem, gpa, nb_blocks, false);
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    virtio_mem_send_response_simple(vmem, elem, type);
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}
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static void virtio_mem_resize_usable_region(VirtIOMEM *vmem,
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                                            uint64_t requested_size,
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                                            bool can_shrink)
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{
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    uint64_t newsize = MIN(memory_region_size(&vmem->memdev->mr),
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                           requested_size + VIRTIO_MEM_USABLE_EXTENT);
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    if (!requested_size) {
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        newsize = 0;
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    }
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    if (newsize < vmem->usable_region_size && !can_shrink) {
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        return;
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    }
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    trace_virtio_mem_resized_usable_region(vmem->usable_region_size, newsize);
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    vmem->usable_region_size = newsize;
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}
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static int virtio_mem_unplug_all(VirtIOMEM *vmem)
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{
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    RAMBlock *rb = vmem->memdev->mr.ram_block;
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    int ret;
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    if (virtio_mem_is_busy()) {
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        return -EBUSY;
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    }
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    ret = ram_block_discard_range(rb, 0, qemu_ram_get_used_length(rb));
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    if (ret) {
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        error_report("Unexpected error discarding RAM: %s", strerror(-ret));
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        return -EBUSY;
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    }
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    bitmap_clear(vmem->bitmap, 0, vmem->bitmap_size);
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    if (vmem->size) {
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        vmem->size = 0;
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        notifier_list_notify(&vmem->size_change_notifiers, &vmem->size);
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    }
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    trace_virtio_mem_unplugged_all();
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    virtio_mem_resize_usable_region(vmem, vmem->requested_size, true);
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    return 0;
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}
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static void virtio_mem_unplug_all_request(VirtIOMEM *vmem,
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                                          VirtQueueElement *elem)
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{
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    trace_virtio_mem_unplug_all_request();
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    if (virtio_mem_unplug_all(vmem)) {
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        virtio_mem_send_response_simple(vmem, elem, VIRTIO_MEM_RESP_BUSY);
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    } else {
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        virtio_mem_send_response_simple(vmem, elem, VIRTIO_MEM_RESP_ACK);
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    }
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}
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static void virtio_mem_state_request(VirtIOMEM *vmem, VirtQueueElement *elem,
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                                     struct virtio_mem_req *req)
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{
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    const uint16_t nb_blocks = le16_to_cpu(req->u.state.nb_blocks);
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    const uint64_t gpa = le64_to_cpu(req->u.state.addr);
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    const uint64_t size = nb_blocks * vmem->block_size;
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    struct virtio_mem_resp resp = {
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        .type = cpu_to_le16(VIRTIO_MEM_RESP_ACK),
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    };
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    trace_virtio_mem_state_request(gpa, nb_blocks);
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    if (!virtio_mem_valid_range(vmem, gpa, size)) {
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        virtio_mem_send_response_simple(vmem, elem, VIRTIO_MEM_RESP_ERROR);
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        return;
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    }
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    if (virtio_mem_test_bitmap(vmem, gpa, size, true)) {
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        resp.u.state.state = cpu_to_le16(VIRTIO_MEM_STATE_PLUGGED);
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    } else if (virtio_mem_test_bitmap(vmem, gpa, size, false)) {
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        resp.u.state.state = cpu_to_le16(VIRTIO_MEM_STATE_UNPLUGGED);
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    } else {
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        resp.u.state.state = cpu_to_le16(VIRTIO_MEM_STATE_MIXED);
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    }
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    trace_virtio_mem_state_response(le16_to_cpu(resp.u.state.state));
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    virtio_mem_send_response(vmem, elem, &resp);
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}
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static void virtio_mem_handle_request(VirtIODevice *vdev, VirtQueue *vq)
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{
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    const int len = sizeof(struct virtio_mem_req);
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    VirtIOMEM *vmem = VIRTIO_MEM(vdev);
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    VirtQueueElement *elem;
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    struct virtio_mem_req req;
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    uint16_t type;
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    while (true) {
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        elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
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        if (!elem) {
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            return;
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        }
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        if (iov_to_buf(elem->out_sg, elem->out_num, 0, &req, len) < len) {
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            virtio_error(vdev, "virtio-mem protocol violation: invalid request"
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                         " size: %d", len);
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            g_free(elem);
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            return;
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        }
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        if (iov_size(elem->in_sg, elem->in_num) <
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            sizeof(struct virtio_mem_resp)) {
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            virtio_error(vdev, "virtio-mem protocol violation: not enough space"
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                         " for response: %zu",
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                         iov_size(elem->in_sg, elem->in_num));
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            g_free(elem);
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            return;
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        }
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        type = le16_to_cpu(req.type);
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        switch (type) {
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        case VIRTIO_MEM_REQ_PLUG:
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            virtio_mem_plug_request(vmem, elem, &req);
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            break;
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        case VIRTIO_MEM_REQ_UNPLUG:
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            virtio_mem_unplug_request(vmem, elem, &req);
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            break;
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        case VIRTIO_MEM_REQ_UNPLUG_ALL:
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            virtio_mem_unplug_all_request(vmem, elem);
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            break;
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        case VIRTIO_MEM_REQ_STATE:
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            virtio_mem_state_request(vmem, elem, &req);
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            break;
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        default:
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            virtio_error(vdev, "virtio-mem protocol violation: unknown request"
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                         " type: %d", type);
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            g_free(elem);
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            return;
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        }
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        g_free(elem);
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    }
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}
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static void virtio_mem_get_config(VirtIODevice *vdev, uint8_t *config_data)
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{
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    VirtIOMEM *vmem = VIRTIO_MEM(vdev);
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    struct virtio_mem_config *config = (void *) config_data;
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    config->block_size = cpu_to_le64(vmem->block_size);
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    config->node_id = cpu_to_le16(vmem->node);
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    config->requested_size = cpu_to_le64(vmem->requested_size);
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    config->plugged_size = cpu_to_le64(vmem->size);
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    config->addr = cpu_to_le64(vmem->addr);
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    config->region_size = cpu_to_le64(memory_region_size(&vmem->memdev->mr));
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    config->usable_region_size = cpu_to_le64(vmem->usable_region_size);
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}
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static uint64_t virtio_mem_get_features(VirtIODevice *vdev, uint64_t features,
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                                        Error **errp)
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{
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    MachineState *ms = MACHINE(qdev_get_machine());
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    if (ms->numa_state) {
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#if defined(CONFIG_ACPI)
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        virtio_add_feature(&features, VIRTIO_MEM_F_ACPI_PXM);
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#endif
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    }
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    return features;
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}
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static void virtio_mem_system_reset(void *opaque)
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{
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    VirtIOMEM *vmem = VIRTIO_MEM(opaque);
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    /*
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     * 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)) {
 | 
						|
        error_setg(errp, "'%s' property specifies a busy memdev: %s",
 | 
						|
                   VIRTIO_MEM_MEMDEV_PROP,
 | 
						|
                   object_get_canonical_path_component(OBJECT(vmem->memdev)));
 | 
						|
        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);
 | 
						|
    precopy_add_notifier(&vmem->precopy_notifier);
 | 
						|
}
 | 
						|
 | 
						|
static void virtio_mem_device_unrealize(DeviceState *dev)
 | 
						|
{
 | 
						|
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 | 
						|
    VirtIOMEM *vmem = VIRTIO_MEM(dev);
 | 
						|
 | 
						|
    precopy_remove_notifier(&vmem->precopy_notifier);
 | 
						|
    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));
 | 
						|
}
 | 
						|
 | 
						|
typedef struct VirtIOMEMMigSanityChecks {
 | 
						|
    VirtIOMEM *parent;
 | 
						|
    uint64_t addr;
 | 
						|
    uint64_t region_size;
 | 
						|
    uint64_t block_size;
 | 
						|
    uint32_t node;
 | 
						|
} VirtIOMEMMigSanityChecks;
 | 
						|
 | 
						|
static int virtio_mem_mig_sanity_checks_pre_save(void *opaque)
 | 
						|
{
 | 
						|
    VirtIOMEMMigSanityChecks *tmp = opaque;
 | 
						|
    VirtIOMEM *vmem = tmp->parent;
 | 
						|
 | 
						|
    tmp->addr = vmem->addr;
 | 
						|
    tmp->region_size = memory_region_size(&vmem->memdev->mr);
 | 
						|
    tmp->block_size = vmem->block_size;
 | 
						|
    tmp->node = vmem->node;
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static int virtio_mem_mig_sanity_checks_post_load(void *opaque, int version_id)
 | 
						|
{
 | 
						|
    VirtIOMEMMigSanityChecks *tmp = opaque;
 | 
						|
    VirtIOMEM *vmem = tmp->parent;
 | 
						|
    const uint64_t new_region_size = memory_region_size(&vmem->memdev->mr);
 | 
						|
 | 
						|
    if (tmp->addr != vmem->addr) {
 | 
						|
        error_report("Property '%s' changed from 0x%" PRIx64 " to 0x%" PRIx64,
 | 
						|
                     VIRTIO_MEM_ADDR_PROP, tmp->addr, vmem->addr);
 | 
						|
        return -EINVAL;
 | 
						|
    }
 | 
						|
    /*
 | 
						|
     * Note: Preparation for resizeable memory regions. The maximum size
 | 
						|
     * of the memory region must not change during migration.
 | 
						|
     */
 | 
						|
    if (tmp->region_size != new_region_size) {
 | 
						|
        error_report("Property '%s' size changed from 0x%" PRIx64 " to 0x%"
 | 
						|
                     PRIx64, VIRTIO_MEM_MEMDEV_PROP, tmp->region_size,
 | 
						|
                     new_region_size);
 | 
						|
        return -EINVAL;
 | 
						|
    }
 | 
						|
    if (tmp->block_size != vmem->block_size) {
 | 
						|
        error_report("Property '%s' changed from 0x%" PRIx64 " to 0x%" PRIx64,
 | 
						|
                     VIRTIO_MEM_BLOCK_SIZE_PROP, tmp->block_size,
 | 
						|
                     vmem->block_size);
 | 
						|
        return -EINVAL;
 | 
						|
    }
 | 
						|
    if (tmp->node != vmem->node) {
 | 
						|
        error_report("Property '%s' changed from %" PRIu32 " to %" PRIu32,
 | 
						|
                     VIRTIO_MEM_NODE_PROP, tmp->node, vmem->node);
 | 
						|
        return -EINVAL;
 | 
						|
    }
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static const VMStateDescription vmstate_virtio_mem_sanity_checks = {
 | 
						|
    .name = "virtio-mem-device/sanity-checks",
 | 
						|
    .pre_save = virtio_mem_mig_sanity_checks_pre_save,
 | 
						|
    .post_load = virtio_mem_mig_sanity_checks_post_load,
 | 
						|
    .fields = (VMStateField[]) {
 | 
						|
        VMSTATE_UINT64(addr, VirtIOMEMMigSanityChecks),
 | 
						|
        VMSTATE_UINT64(region_size, VirtIOMEMMigSanityChecks),
 | 
						|
        VMSTATE_UINT64(block_size, VirtIOMEMMigSanityChecks),
 | 
						|
        VMSTATE_UINT32(node, VirtIOMEMMigSanityChecks),
 | 
						|
        VMSTATE_END_OF_LIST(),
 | 
						|
    },
 | 
						|
};
 | 
						|
 | 
						|
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_WITH_TMP(VirtIOMEM, VirtIOMEMMigSanityChecks,
 | 
						|
                         vmstate_virtio_mem_sanity_checks),
 | 
						|
        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_add_size_change_notifier(VirtIOMEM *vmem,
 | 
						|
                                                Notifier *notifier)
 | 
						|
{
 | 
						|
    notifier_list_add(&vmem->size_change_notifiers, notifier);
 | 
						|
}
 | 
						|
 | 
						|
static void virtio_mem_remove_size_change_notifier(VirtIOMEM *vmem,
 | 
						|
                                                   Notifier *notifier)
 | 
						|
{
 | 
						|
    notifier_remove(notifier);
 | 
						|
}
 | 
						|
 | 
						|
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_precopy_exclude_unplugged(VirtIOMEM *vmem)
 | 
						|
{
 | 
						|
    void * const host = qemu_ram_get_host_addr(vmem->memdev->mr.ram_block);
 | 
						|
    unsigned long first_zero_bit, last_zero_bit;
 | 
						|
    uint64_t offset, length;
 | 
						|
 | 
						|
    /*
 | 
						|
     * Find consecutive unplugged blocks and exclude them from migration.
 | 
						|
     *
 | 
						|
     * Note: Blocks cannot get (un)plugged during precopy, no locking needed.
 | 
						|
     */
 | 
						|
    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;
 | 
						|
 | 
						|
        qemu_guest_free_page_hint(host + offset, length);
 | 
						|
        first_zero_bit = find_next_zero_bit(vmem->bitmap, vmem->bitmap_size,
 | 
						|
                                            last_zero_bit + 2);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static int virtio_mem_precopy_notify(NotifierWithReturn *n, void *data)
 | 
						|
{
 | 
						|
    VirtIOMEM *vmem = container_of(n, VirtIOMEM, precopy_notifier);
 | 
						|
    PrecopyNotifyData *pnd = data;
 | 
						|
 | 
						|
    switch (pnd->reason) {
 | 
						|
    case PRECOPY_NOTIFY_SETUP:
 | 
						|
        precopy_enable_free_page_optimization();
 | 
						|
        break;
 | 
						|
    case PRECOPY_NOTIFY_AFTER_BITMAP_SYNC:
 | 
						|
        virtio_mem_precopy_exclude_unplugged(vmem);
 | 
						|
        break;
 | 
						|
    default:
 | 
						|
        break;
 | 
						|
    }
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static void virtio_mem_instance_init(Object *obj)
 | 
						|
{
 | 
						|
    VirtIOMEM *vmem = VIRTIO_MEM(obj);
 | 
						|
 | 
						|
    vmem->block_size = VIRTIO_MEM_MIN_BLOCK_SIZE;
 | 
						|
    notifier_list_init(&vmem->size_change_notifiers);
 | 
						|
    vmem->precopy_notifier.notify = virtio_mem_precopy_notify;
 | 
						|
 | 
						|
    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;
 | 
						|
    vmc->add_size_change_notifier = virtio_mem_add_size_change_notifier;
 | 
						|
    vmc->remove_size_change_notifier = virtio_mem_remove_size_change_notifier;
 | 
						|
}
 | 
						|
 | 
						|
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)
 |