From patchwork Fri Sep 25 13:48:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 304403 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS 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 3D4EDC4363D for ; Fri, 25 Sep 2020 13:55:46 +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 BBF14206C9 for ; Fri, 25 Sep 2020 13:55:45 +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="ir8IhASS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BBF14206C9 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]:54572 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLoCO-0001h2-EF for qemu-devel@archiver.kernel.org; Fri, 25 Sep 2020 09:55:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35366) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kLo6w-0003tm-1n for qemu-devel@nongnu.org; Fri, 25 Sep 2020 09:50:07 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:43617) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kLo6s-0000ps-0u for qemu-devel@nongnu.org; Fri, 25 Sep 2020 09:50:04 -0400 Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601041798; 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=fLvjjbnseEvWZyZlxkrX+W1Hx+rNQ9Jg98KLgwjIUh0=; b=ir8IhASSfIG71X7ZkLp8wJzrmpD7klhPzoOvKNpE5GerdxbH8gp/RxQbD2lYJjGLE+wYuG Z65D3ifu8JFOnQe1MXCBo0Jvnr+U2ht6VdY3BUIv8C6oTEoIaDD2WUfiXq6o392tOuGY8l izfQpDhJqKVEiEd1aVFi+HBI1WnDh40= 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-557-_u9TE8skM56EMqOW5PgM4Q-1; Fri, 25 Sep 2020 09:49:57 -0400 X-MC-Unique: _u9TE8skM56EMqOW5PgM4Q-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C183F1084C9E; Fri, 25 Sep 2020 13:49:55 +0000 (UTC) Received: from laptop.redhat.com (ovpn-113-81.ams2.redhat.com [10.36.113.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id 742DE5D9DC; Fri, 25 Sep 2020 13:49:09 +0000 (UTC) From: Eric Auger To: eric.auger.pro@gmail.com, eric.auger@redhat.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, stefanha@redhat.com, fam@euphon.net, philmd@redhat.com, alex.williamson@redhat.com Subject: [RFC 3/3] util/vfio-helpers: Rework the IOVA allocator to avoid IOVA reserved regions Date: Fri, 25 Sep 2020 15:48:45 +0200 Message-Id: <20200925134845.21053-4-eric.auger@redhat.com> In-Reply-To: <20200925134845.21053-1-eric.auger@redhat.com> References: <20200925134845.21053-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eric.auger@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=eric.auger@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/25 02:48:20 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] 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=-1.199, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=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: lvivier@redhat.com, kwolf@redhat.com, cohuck@redhat.com, mreitz@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Signed-off-by: Eric Auger --- util/vfio-helpers.c | 55 +++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 51 insertions(+), 4 deletions(-) diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c index 567bcf1ded..c98d0d882e 100644 --- a/util/vfio-helpers.c +++ b/util/vfio-helpers.c @@ -676,6 +676,48 @@ static bool qemu_vfio_verify_mappings(QEMUVFIOState *s) return true; } +static int +qemu_vfio_find_fixed_iova(QEMUVFIOState *s, size_t size, uint64_t *iova) +{ + int i; + + for (i = 0; i < s->nb_iova_ranges; i++) { + if (s->usable_iova_ranges[i].end < s->low_water_mark) { + continue; + } + s->low_water_mark = + MAX(s->low_water_mark, s->usable_iova_ranges[i].start); + + if (s->usable_iova_ranges[i].end - s->low_water_mark + 1 >= size) { + *iova = s->low_water_mark; + s->low_water_mark += size; + return 0; + } + } + return -ENOMEM; +} + +static int +qemu_vfio_find_temp_iova(QEMUVFIOState *s, size_t size, uint64_t *iova) +{ + int i; + + for (i = s->nb_iova_ranges - 1; i >= 0; i--) { + if (s->usable_iova_ranges[i].start > s->high_water_mark) { + continue; + } + s->high_water_mark = + MIN(s->high_water_mark, s->usable_iova_ranges[i].end + 1); + + if (s->high_water_mark - s->usable_iova_ranges[i].start + 1 >= size) { + *iova = s->high_water_mark - size; + s->high_water_mark = *iova; + return 0; + } + } + return -ENOMEM; +} + /* Map [host, host + size) area into a contiguous IOVA address space, and store * the result in @iova if not NULL. The caller need to make sure the area is * aligned to page size, and mustn't overlap with existing mapping areas (split @@ -702,7 +744,11 @@ int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size, goto out; } if (!temporary) { - iova0 = s->low_water_mark; + if (qemu_vfio_find_fixed_iova(s, size, &iova0)) { + ret = -ENOMEM; + goto out; + } + mapping = qemu_vfio_add_mapping(s, host, size, index + 1, iova0); if (!mapping) { ret = -ENOMEM; @@ -714,15 +760,16 @@ int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size, qemu_vfio_undo_mapping(s, mapping, NULL); goto out; } - s->low_water_mark += size; qemu_vfio_dump_mappings(s); } else { - iova0 = s->high_water_mark - size; + if (qemu_vfio_find_temp_iova(s, size, &iova0)) { + ret = -ENOMEM; + goto out; + } ret = qemu_vfio_do_mapping(s, host, size, iova0); if (ret) { goto out; } - s->high_water_mark -= size; } } if (iova) {