Signed-off-by: David Hildenbrand <da...@redhat.com> --- hw/virtio/virtio-mem.c | 168 ++++++++++++++++++++++++++--------------- 1 file changed, 109 insertions(+), 59 deletions(-)
diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 093b6eb0bb..d28b501778 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -237,30 +237,78 @@ static void virtio_mem_unplug_request(VirtIOMEM *vm, VirtQueueElement *elem, virtio_mem_send_response_simple(vm, elem, type); } +/* + * Try to resize the usable region to hold at least the requested size. + */ +static void virtio_mem_resize_usable_region(VirtIOMEM *vm, + uint64_t requested_size, + Error **errp) +{ + /* + * If possible, we size the usable region a little bit bigger than the + * requested size, so the guest has more flexibility. + */ + uint64_t newsize = MIN(memory_region_max_size(&vm->memdev->mr), + requested_size + VIRTIO_MEM_USABLE_EXTENT); + Error *err = NULL; + + /* + * Size it as small as possible (0 is not valid). + */ + if (!requested_size) { + newsize = vm->block_size; + } + + if (newsize == vm->usable_region_size) { + return; + } + + /* resize the memory region, if supported */ + if (memory_region_is_resizable(&vm->memdev->mr)) { + memory_region_ram_resize(&vm->memdev->mr, newsize, &err); + } + if (!err) { + vm->usable_region_size = newsize; + fprintf(stderr, "New usable_region_size: %" PRIx64 "\n", + vm->usable_region_size); + } + error_propagate(errp, err); +} + /* * Unplug all memory and shrink the usable region. */ -static void virtio_mem_unplug_all(VirtIOMEM *vm) +static int virtio_mem_unplug_all(VirtIOMEM *vm) { + Error *err = NULL; + + if (virtio_mem_busy()) { + return -EBUSY; + } + + virtio_mem_resize_usable_region(vm, vm->requested_size, &err); + if (err) { + /* It's unlikely that shrinking fails. */ + warn_report_err(err); + return -ENOMEM; + } if (vm->size) { - virtio_mem_set_block_state(vm, vm->addr, - memory_region_size(&vm->memdev->mr), false); + ram_block_discard_range(vm->memdev->mr.ram_block, 0, + memory_region_size(&vm->memdev->mr)); + bitmap_clear(vm->bitmap, 0, vm->bitmap_size); vm->size = 0; } - vm->usable_region_size = MIN(memory_region_size(&vm->memdev->mr), - vm->requested_size + VIRTIO_MEM_USABLE_EXTENT); + return 0; } static void virtio_mem_unplug_all_request(VirtIOMEM *vm, VirtQueueElement *elem) { - if (virtio_mem_busy()) { + if (virtio_mem_unplug_all(vm)) { virtio_mem_send_response_simple(vm, elem, VIRTIO_MEM_RESP_BUSY); - return; + } else { + virtio_mem_send_response_simple(vm, elem, VIRTIO_MEM_RESP_ACK); } - - virtio_mem_unplug_all(vm); - virtio_mem_send_response_simple(vm, elem, VIRTIO_MEM_RESP_ACK); } static void virtio_mem_state_request(VirtIOMEM *vm, VirtQueueElement *elem, @@ -344,7 +392,7 @@ static void virtio_mem_get_config(VirtIODevice *vdev, uint8_t *config_data) config->requested_size = cpu_to_le64(vm->requested_size); config->plugged_size = cpu_to_le64(vm->size); config->addr = cpu_to_le64(vm->addr); - config->region_size = cpu_to_le64(memory_region_size(&vm->memdev->mr)); + config->region_size = cpu_to_le64(memory_region_max_size(&vm->memdev->mr)); config->usable_region_size = cpu_to_le64(vm->usable_region_size); } @@ -370,10 +418,6 @@ static void virtio_mem_system_reset(void *opaque) * region size. This is, however, not possible in all scenarios. Then, * the guest has to deal with this manually (VIRTIO_MEM_REQ_UNPLUG_ALL). */ - if (virtio_mem_busy()) { - return; - } - virtio_mem_unplug_all(vm); } @@ -410,32 +454,32 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) int nb_numa_nodes = ms->numa_state ? ms->numa_state->num_nodes : 0; VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIOMEM *vm = VIRTIO_MEM(dev); - Error *local_err = NULL; + Error *err = NULL; uint64_t page_size; /* verify the memdev */ host_memory_backend_validate(vm->memdev, VIRTIO_MEM_MEMDEV_PROP, - false, &local_err); - if (local_err) { - error_propagate(errp, local_err); + true, &err); + if (err) { + error_propagate(errp, err); return; } /* verify the node */ if ((nb_numa_nodes && vm->node >= nb_numa_nodes) || (!nb_numa_nodes && vm->node)) { - error_setg(&local_err, "Property '%s' has value '%" PRIu32 + error_setg(errp, "Property '%s' has value '%" PRIu32 "', which exceeds the number of numa nodes: %d", VIRTIO_MEM_NODE_PROP, vm->node, nb_numa_nodes ? nb_numa_nodes : 1); - goto out; + return; } /* mmap/madvise changes have to be reflected in guest physical memory */ if (kvm_enabled() && !kvm_has_sync_mmu()) { - error_set(&local_err, ERROR_CLASS_KVM_MISSING_CAP, + error_set(errp, ERROR_CLASS_KVM_MISSING_CAP, "Using KVM without synchronous MMU, virtio-mem unavailable"); - goto out; + return; } /* @@ -443,8 +487,14 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) * to temporarily unlock and relock at the right places to make it work. */ if (enable_mlock) { - error_setg(&local_err, "Memory is locked, virtio-mem unavailable"); - goto out; + error_setg(errp, "Memory is locked, virtio-mem unavailable"); + return; + } + + if (virtio_mem_busy()) { + error_setg(errp, "virtio-mem devices cannot be created while migrating," + " while dumping, or when certain vfio devices are used."); + return; } g_assert(memory_region_is_ram(&vm->memdev->mr)); @@ -458,37 +508,37 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) */ page_size = qemu_ram_pagesize(vm->memdev->mr.ram_block); if (page_size != getpagesize()) { - error_setg(&local_err, "'%s' page size (0x%" PRIx64 ") not supported", + error_setg(errp, "'%s' page size (0x%" PRIx64 ") not supported", VIRTIO_MEM_MEMDEV_PROP, page_size); - goto out; + return; } /* now that memdev and block_size is fixed, verify the properties */ if (vm->block_size < page_size) { - error_setg(&local_err, "'%s' has to be at least the page size (0x%" + error_setg(errp, "'%s' has to be at least the page size (0x%" PRIx64 ")", VIRTIO_MEM_BLOCK_SIZE_PROP, page_size); - goto out; + return; } else if (!QEMU_IS_ALIGNED(vm->requested_size, vm->block_size)) { error_setg(errp, "'%s' has to be multiples of '%s' (0x%" PRIx32 ")", VIRTIO_MEM_REQUESTED_SIZE_PROP, VIRTIO_MEM_BLOCK_SIZE_PROP, vm->block_size); - } else if (!QEMU_IS_ALIGNED(memory_region_size(&vm->memdev->mr), + return; + } else if (!QEMU_IS_ALIGNED(memory_region_max_size(&vm->memdev->mr), vm->block_size)) { - error_setg(&local_err, "'%s' size has to be multiples of '%s' (0x%" + error_setg(errp, "'%s' size has to be multiples of '%s' (0x%" PRIx32 ")", VIRTIO_MEM_MEMDEV_PROP, VIRTIO_MEM_BLOCK_SIZE_PROP, vm->block_size); - goto out; + return; } - /* - * If possible, we size the usable region a little bit bigger than the - * requested size, so the guest has more flexibility. - */ - vm->usable_region_size = MIN(memory_region_size(&vm->memdev->mr), - vm->requested_size + VIRTIO_MEM_USABLE_EXTENT); + virtio_mem_resize_usable_region(vm, vm->requested_size, &err); + if (err) { + error_propagate(errp, err); + return; + } /* allocate the bitmap for tracking the state of a block */ - vm->bitmap_size = memory_region_size(&vm->memdev->mr) / vm->block_size; + vm->bitmap_size = memory_region_max_size(&vm->memdev->mr) / vm->block_size; vm->bitmap = bitmap_new(vm->bitmap_size); /* all memory is unplugged initially */ @@ -505,8 +555,6 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) vm->postcopy_notifier.notify = virtio_mem_postcopy_notifier; postcopy_add_notifier(&vm->postcopy_notifier); qemu_register_reset(virtio_mem_system_reset, vm); -out: - error_propagate(errp, local_err); } static void virtio_mem_device_unrealize(DeviceState *dev, Error **errp) @@ -603,7 +651,7 @@ static void virtio_mem_fill_device_info(const VirtIOMEM *vmem, vi->node = vmem->node; vi->requested_size = vmem->requested_size; vi->size = vmem->size; - vi->max_size = memory_region_size(&vmem->memdev->mr); + vi->max_size = memory_region_max_size(&vmem->memdev->mr); vi->block_size = vmem->block_size; vi->memdev = object_get_canonical_path(OBJECT(vmem->memdev)); } @@ -651,14 +699,6 @@ static void virtio_mem_set_requested_size(Object *obj, Visitor *v, return; } - /* Growing the usable region might later not be possible, disallow it. */ - if (virtio_mem_busy() && value > vm->requested_size) { - error_setg(errp, "'%s' cannot be increased while migrating," - " while dumping, or when certain vfio devices are used.", - name); - return; - } - /* * The block size and memory backend are not fixed until the device was * realized. realize() will verify these properties then. @@ -669,22 +709,32 @@ static void virtio_mem_set_requested_size(Object *obj, Visitor *v, ")", name, VIRTIO_MEM_BLOCK_SIZE_PROP, vm->block_size); return; - } else if (value > memory_region_size(&vm->memdev->mr)) { + } else if (value > memory_region_max_size(&vm->memdev->mr)) { error_setg(errp, "'%s' cannot exceed the memory backend size" "(0x%" PRIx64 ")", name, - memory_region_size(&vm->memdev->mr)); + memory_region_max_size(&vm->memdev->mr)); return; } if (value != vm->requested_size) { - uint64_t tmp_size; - + if (virtio_mem_busy()) { + error_setg(errp, "'%s' cannot be changed while migrating," + " while dumping, or when certain vfio devices are used.", + name); + return; + } + + /* We are only allowed to grow the region */ + if (value > vm->requested_size) { + Error *err = NULL; + + virtio_mem_resize_usable_region(vm, value, &err); + if (err) { + error_propagate(errp, err); + return; + } + } vm->requested_size = value; - - /* Grow the usable region if required */ - tmp_size = MIN(memory_region_size(&vm->memdev->mr), - vm->requested_size + VIRTIO_MEM_USABLE_EXTENT); - vm->usable_region_size = MAX(vm->usable_region_size, tmp_size); } /* * Trigger a config update so the guest gets notified. We trigger -- 2.24.1