From patchwork Mon Oct 5 15:43:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 11816911 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 1BE09139A for ; Mon, 5 Oct 2020 15:53:26 +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 D3DF720639 for ; Mon, 5 Oct 2020 15:53:25 +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="Ig+ZQm1f" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D3DF720639 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]:59466 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kPSnl-0001AY-00 for patchwork-qemu-devel@patchwork.kernel.org; Mon, 05 Oct 2020 11:53:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57002) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kPSfT-0006Ez-SR for qemu-devel@nongnu.org; Mon, 05 Oct 2020 11:44:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:44912) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kPSfN-0008Lh-OE for qemu-devel@nongnu.org; Mon, 05 Oct 2020 11:44:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601912684; 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=O5QARRmCXxm1BipHqnlxMxzhlAY+C26xXKhU5QRMwDk=; b=Ig+ZQm1fSe4hoOqdXzgFUINjPf0nAUuH7Jyq78ZzYtG/MEES09vWpCHZlWirc89YWhIwOv vSabNIhNi6ZO+MlhTN1w4z1jfGstaUF51LG0mcXZXzgZ9iJja1OsstoP40J8ahBHrWCM4J M4vNjsWFap3avgYGBsdsjOwusdzho3A= 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-282-WztZws8SPfSs7fqSa-iuwQ-1; Mon, 05 Oct 2020 11:44:42 -0400 X-MC-Unique: WztZws8SPfSs7fqSa-iuwQ-1 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 A7FE91019627; Mon, 5 Oct 2020 15:44:40 +0000 (UTC) Received: from localhost (ovpn-112-117.ams2.redhat.com [10.36.112.117]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2893F19C4F; Mon, 5 Oct 2020 15:44:34 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org, Peter Maydell Subject: [PULL v2 17/17] util/vfio-helpers: Rework the IOVA allocator to avoid IOVA reserved regions Date: Mon, 5 Oct 2020 16:43:23 +0100 Message-Id: <20201005154323.31347-18-stefanha@redhat.com> In-Reply-To: <20201005154323.31347-1-stefanha@redhat.com> References: <20201005154323.31347-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/05 01:25:11 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.733, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MIME_BASE64_TEXT=1.741, 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=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: Kevin Wolf , Fam Zheng , Eduardo Habkost , qemu-block@nongnu.org, Max Reitz , Eric Auger , Stefan Hajnoczi , Cleber Rosa Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Eric Auger Introduce the qemu_vfio_find_fixed/temp_iova helpers which respectively allocate IOVAs from the bottom/top parts of the usable IOVA range, without picking within host IOVA reserved windows. The allocation remains basic: if the size is too big for the remaining of the current usable IOVA range, we jump to the next one, leaving a hole in the address map. Signed-off-by: Eric Auger Message-id: 20200929085550.30926-3-eric.auger@redhat.com Signed-off-by: Stefan Hajnoczi --- util/vfio-helpers.c | 57 +++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 53 insertions(+), 4 deletions(-) diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c index fe9ca9ce38..c469beb061 100644 --- a/util/vfio-helpers.c +++ b/util/vfio-helpers.c @@ -667,6 +667,50 @@ 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 || + s->usable_iova_ranges[i].end - s->low_water_mark + 1 == 0) { + *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 || + s->high_water_mark - s->usable_iova_ranges[i].start + 1 == 0) { + *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 @@ -693,7 +737,11 @@ 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; @@ -705,15 +753,16 @@ 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) {