From patchwork Wed Feb 12 13:35:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11378587 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BB5C513A4 for ; Wed, 12 Feb 2020 13:47:17 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 804A721734 for ; Wed, 12 Feb 2020 13:47:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="f1+GqAIC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 804A721734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:38088 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j1sMG-00048d-ID for patchwork-qemu-devel@patchwork.kernel.org; Wed, 12 Feb 2020 08:47:16 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38199) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j1sCH-00031L-1T for qemu-devel@nongnu.org; Wed, 12 Feb 2020 08:36:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j1sCD-0006ZS-AO for qemu-devel@nongnu.org; Wed, 12 Feb 2020 08:36:56 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:50887 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j1sCD-0006Z3-4S for qemu-devel@nongnu.org; Wed, 12 Feb 2020 08:36:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1581514612; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3bTtXEQ8dqtzeP/iMuBtkOVb+vgeMWBv8YNFu0jiydM=; b=f1+GqAICYIZos2YhBknDkIMSIafRcd7AsxlZxpzU8JLndZ6u/NxDCz6SWMAL9RblkONyRS CCTDjhM9/hsUOfzCh8yDUurlMeVkmFKSnER+AIlaiAlC7oiDJLzAkY2qSN/T55SoBzVED3 jA50tnlkoXJh9kSocWIeyI71GBLsZmI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-4-GFHUODnPNnSs-TGdmLC1nA-1; Wed, 12 Feb 2020 08:36:51 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3DDB5107ACC5; Wed, 12 Feb 2020 13:36:50 +0000 (UTC) Received: from t480s.redhat.com (ovpn-117-92.ams2.redhat.com [10.36.117.92]) by smtp.corp.redhat.com (Postfix) with ESMTP id 77CEB19C69; Wed, 12 Feb 2020 13:36:48 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v2 14/16] virtio-mem: Support for resizable memory regions Date: Wed, 12 Feb 2020 14:35:59 +0100 Message-Id: <20200212133601.10555-15-david@redhat.com> In-Reply-To: <20200212133601.10555-1-david@redhat.com> References: <20200212133601.10555-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: GFHUODnPNnSs-TGdmLC1nA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S . Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Igor Mammedov , Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" Signed-off-by: David Hildenbrand --- 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