From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0867BC433E6 for ; Thu, 14 Jan 2021 16:34:29 +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 B3A4323772 for ; Thu, 14 Jan 2021 16:34:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B3A4323772 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+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:44202 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l05Zr-00079X-CN for qemu-devel@archiver.kernel.org; Thu, 14 Jan 2021 11:34:27 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:60622) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l050D-0008Vu-LZ for qemu-devel@nongnu.org; Thu, 14 Jan 2021 10:57:42 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:56128) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l0501-0000D0-Ak for qemu-devel@nongnu.org; Thu, 14 Jan 2021 10:57:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610639844; 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=h2Fb23QGHP9O9Qe44X0FIy35a1lGNwTY+7Py9pmOOhU=; b=czCY2NC7XBhl1SAt6dG8wA7PYtoYQ4pNEprKLGVBJnSjARW60HIFbw0mAQmYRVM40Foro7 uKTurIhpSzJKME1k7O56qzsAYJcDQCw9WofOQfKW0cBBD8UKxwxHu1BdWJkAxW8fxySRHs 5Mhbka6D2ReKTu6OerPUmKCNSLaEfKg= 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-412-4FUDMlN1O96_MFPqGwzOtA-1; Thu, 14 Jan 2021 10:57:22 -0500 X-MC-Unique: 4FUDMlN1O96_MFPqGwzOtA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 43DB38145F8; Thu, 14 Jan 2021 15:57:20 +0000 (UTC) Received: from [10.36.115.75] (ovpn-115-75.ams2.redhat.com [10.36.115.75]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9AE7363746; Thu, 14 Jan 2021 15:57:05 +0000 (UTC) Subject: Re: [PATCH v4 04/11] vfio: Support for RamDiscardMgr in the !vIOMMU case From: David Hildenbrand To: Alex Williamson References: <20210107133423.44964-1-david@redhat.com> <20210107133423.44964-5-david@redhat.com> <20210113162745.5c92e04f@omen.home.shazbot.org> <651d5ef7-096f-0b71-2190-53532dab3dd0@redhat.com> Organization: Red Hat GmbH Message-ID: Date: Thu, 14 Jan 2021 16:57:04 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <651d5ef7-096f-0b71-2190-53532dab3dd0@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.248, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.237, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action 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: Pankaj Gupta , Wei Yang , "Michael S. Tsirkin" , Jonathan Cameron , qemu-devel@nongnu.org, Peter Xu , "Dr . David Alan Gilbert" , Auger Eric , teawater , Igor Mammedov , Paolo Bonzini , Marek Kedzierski Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 14.01.21 16:54, David Hildenbrand wrote: > On 14.01.21 00:27, Alex Williamson wrote: >> On Thu, 7 Jan 2021 14:34:16 +0100 >> David Hildenbrand wrote: >> >>> Implement support for RamDiscardMgr, to prepare for virtio-mem >>> support. Instead of mapping the whole memory section, we only map >>> "populated" parts and update the mapping when notified about >>> discarding/population of memory via the RamDiscardListener. Similarly, when >>> syncing the dirty bitmaps, sync only the actually mapped (populated) parts >>> by replaying via the notifier. >>> >>> Using virtio-mem with vfio is still blocked via >>> ram_block_discard_disable()/ram_block_discard_require() after this patch. >>> >>> Cc: Paolo Bonzini >>> Cc: "Michael S. Tsirkin" >>> Cc: Alex Williamson >>> Cc: Dr. David Alan Gilbert >>> Cc: Igor Mammedov >>> Cc: Pankaj Gupta >>> Cc: Peter Xu >>> Cc: Auger Eric >>> Cc: Wei Yang >>> Cc: teawater >>> Cc: Marek Kedzierski >>> Signed-off-by: David Hildenbrand >>> --- >>> hw/vfio/common.c | 200 ++++++++++++++++++++++++++++++++++ >>> include/hw/vfio/vfio-common.h | 12 ++ >>> 2 files changed, 212 insertions(+) >>> >>> diff --git a/hw/vfio/common.c b/hw/vfio/common.c >>> index 6ff1daa763..2bd219cf1d 100644 >>> --- a/hw/vfio/common.c >>> +++ b/hw/vfio/common.c >>> @@ -654,6 +654,136 @@ out: >>> rcu_read_unlock(); >>> } >>> >>> +static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl, >>> + const MemoryRegion *mr, >>> + ram_addr_t offset, ram_addr_t size) >>> +{ >>> + VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, >>> + listener); >>> + const hwaddr mr_start = MAX(offset, vrdl->offset_within_region); >>> + const hwaddr mr_end = MIN(offset + size, >>> + vrdl->offset_within_region + vrdl->size); >>> + const hwaddr iova = mr_start - vrdl->offset_within_region + >>> + vrdl->offset_within_address_space; >>> + int ret; >>> + >>> + if (mr_start >= mr_end) { >>> + return; >>> + } >>> + >>> + /* Unmap with a single call. */ >>> + ret = vfio_dma_unmap(vrdl->container, iova, mr_end - mr_start, NULL); >>> + if (ret) { >>> + error_report("%s: vfio_dma_unmap() failed: %s", __func__, >>> + strerror(-ret)); >>> + } >>> +} >>> + >>> +static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl, >>> + const MemoryRegion *mr, >>> + ram_addr_t offset, ram_addr_t size) >>> +{ >>> + VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, >>> + listener); >>> + const hwaddr mr_end = MIN(offset + size, >>> + vrdl->offset_within_region + vrdl->size); >>> + hwaddr mr_start = MAX(offset, vrdl->offset_within_region); >>> + hwaddr mr_next, iova; >>> + void *vaddr; >>> + int ret; >>> + >>> + /* >>> + * Map in (aligned within memory region) minimum granularity, so we can >>> + * unmap in minimum granularity later. >>> + */ >>> + for (; mr_start < mr_end; mr_start = mr_next) { >>> + mr_next = ROUND_UP(mr_start + 1, vrdl->granularity); >>> + mr_next = MIN(mr_next, mr_end); >>> + >>> + iova = mr_start - vrdl->offset_within_region + >>> + vrdl->offset_within_address_space; >>> + vaddr = memory_region_get_ram_ptr(vrdl->mr) + mr_start; >>> + >>> + ret = vfio_dma_map(vrdl->container, iova, mr_next - mr_start, >>> + vaddr, mr->readonly); >>> + if (ret) { >>> + /* Rollback */ >>> + vfio_ram_discard_notify_discard(rdl, mr, offset, size); >>> + return ret; >>> + } >>> + } >>> + return 0; >>> +} >>> + >>> +static void vfio_ram_discard_notify_discard_all(RamDiscardListener *rdl, >>> + const MemoryRegion *mr) >>> +{ >>> + VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, >>> + listener); >>> + int ret; >>> + >>> + /* Unmap with a single call. */ >>> + ret = vfio_dma_unmap(vrdl->container, vrdl->offset_within_address_space, >>> + vrdl->size, NULL); >>> + if (ret) { >>> + error_report("%s: vfio_dma_unmap() failed: %s", __func__, >>> + strerror(-ret)); >>> + } >>> +} >>> + >>> +static void vfio_register_ram_discard_notifier(VFIOContainer *container, >>> + MemoryRegionSection *section) >>> +{ >>> + RamDiscardMgr *rdm = memory_region_get_ram_discard_mgr(section->mr); >>> + RamDiscardMgrClass *rdmc = RAM_DISCARD_MGR_GET_CLASS(rdm); >>> + VFIORamDiscardListener *vrdl; >>> + >>> + vrdl = g_new0(VFIORamDiscardListener, 1); >>> + vrdl->container = container; >>> + vrdl->mr = section->mr; >>> + vrdl->offset_within_region = section->offset_within_region; >>> + vrdl->offset_within_address_space = section->offset_within_address_space; >>> + vrdl->size = int128_get64(section->size); >>> + vrdl->granularity = rdmc->get_min_granularity(rdm, section->mr); >>> + >>> + /* Ignore some corner cases not relevant in practice. */ >>> + g_assert(QEMU_IS_ALIGNED(vrdl->offset_within_region, TARGET_PAGE_SIZE)); >>> + g_assert(QEMU_IS_ALIGNED(vrdl->offset_within_address_space, >>> + TARGET_PAGE_SIZE)); >>> + g_assert(QEMU_IS_ALIGNED(vrdl->size, TARGET_PAGE_SIZE)); >> >> Should probably toss in a test of vrdl->granularity vs >> container->pgsizes too, right? Looks good otherwise: > > Makes sense as a sanity check. What about > > g_assert(vrdl->granularity && !is_power_of_2(vrdl->granularity)); ^ g_assert(vrdl->granularity >= 1 << ctz64(container->pgsizes)); -- Thanks, David / dhildenb