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=-15.1 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 C7A4BC433DB for ; Fri, 15 Jan 2021 10:29:21 +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 591F2224F9 for ; Fri, 15 Jan 2021 10:29:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 591F2224F9 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]:47300 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l0MM4-00013b-FV for qemu-devel@archiver.kernel.org; Fri, 15 Jan 2021 05:29:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:57992) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l0MKW-0007q9-9T for qemu-devel@nongnu.org; Fri, 15 Jan 2021 05:27:44 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:55753) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l0MKU-0000uk-Cv for qemu-devel@nongnu.org; Fri, 15 Jan 2021 05:27:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610706461; 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=DlyKwa+h6ktjs4tjrEI39rWNicK/UMxDrl3youZ9jF8=; b=dSJxhdZRjJvK1Y9GQzcGeUq0gUQz9i+jlPwH48SnDhZJBCR9jgqDqXdO2IMs2cagF80xwn kgMIoYHhlTAbvxqhl6N9V6WQ4TS4x+G+vJ/pffQcLmdBR57oeFE+GQsbf4VYFyHlRDthH1 zD4qV06JKgYZMpemYD7+aFGnx8Di5iA= 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-374-gfWmWReGMyqbd9nJpFKFMg-1; Fri, 15 Jan 2021 05:27:37 -0500 X-MC-Unique: gfWmWReGMyqbd9nJpFKFMg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4545B19611A2; Fri, 15 Jan 2021 10:27:36 +0000 (UTC) Received: from [10.36.112.11] (ovpn-112-11.ams2.redhat.com [10.36.112.11]) by smtp.corp.redhat.com (Postfix) with ESMTP id 46A9E100AE3F; Fri, 15 Jan 2021 10:27:21 +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: <1fd4e7c2-067b-4a19-3940-65c3df3b18a1@redhat.com> Date: Fri, 15 Jan 2021 11:27:20 +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: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 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=ham 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 16:57, David Hildenbrand wrote: > 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)); > Ehm, I guess my brain needs some time to cool down over the weekend :D + g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity)); + g_assert(vrdl->granularity >= 1 << ctz64(container->pgsizes)); -- Thanks, David / dhildenb