From patchwork Mon Sep 7 11:08:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 11760647 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 491C259D for ; Mon, 7 Sep 2020 11:17:17 +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 C2C322166E for ; Mon, 7 Sep 2020 11:17:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iQLCGQz/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C2C322166E 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]:33182 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kFF99-0007Gy-RB for patchwork-qemu-devel@patchwork.kernel.org; Mon, 07 Sep 2020 07:17:15 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58662) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kFF26-00022d-Hs for qemu-devel@nongnu.org; Mon, 07 Sep 2020 07:09:58 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:38067 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kFF24-0007su-Sq for qemu-devel@nongnu.org; Mon, 07 Sep 2020 07:09:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599476996; 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=tNvuxDHW2UclE/Ad5IT65+egvp89LXNP48q4m9ZZImI=; b=iQLCGQz/O54islRKJenkN6cm0tSghxzjxGYQRgH+Y8CfWNUtUxUAAIsu4Qdc1iNjFZgtR8 rmktp8KeZc3D3sqlOkIRJ+rIvMP1em/5FGiWxN/7sxirTt/kVMENRImySwczpHikCyJn/Q 7b78qL2tZeluQxpgh+S1IQ92XBLQBoI= 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-537-ai3ABksUNbSVXFgqSr2A2g-1; Mon, 07 Sep 2020 07:09:54 -0400 X-MC-Unique: ai3ABksUNbSVXFgqSr2A2g-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5F15B18B9EC1; Mon, 7 Sep 2020 11:09:53 +0000 (UTC) Received: from linux.fritz.box.com (ovpn-114-154.ams2.redhat.com [10.36.114.154]) by smtp.corp.redhat.com (Postfix) with ESMTP id 68D0E9CBA; Mon, 7 Sep 2020 11:09:52 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Subject: [PULL 09/64] block/nvme: Use union of NvmeIdCtrl / NvmeIdNs structures Date: Mon, 7 Sep 2020 13:08:41 +0200 Message-Id: <20200907110936.261684-10-kwolf@redhat.com> In-Reply-To: <20200907110936.261684-1-kwolf@redhat.com> References: <20200907110936.261684-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=kwolf@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/07 02:54:37 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.1, 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_H2=-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: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Philippe Mathieu-Daudé We allocate an unique chunk of memory then use it for two different structures. By using an union, we make it clear the data is overlapping (and we can remove the casts). Suggested-by: Stefan Hajnoczi Reviewed-by: Stefan Hajnoczi Reviewed-by: Stefano Garzarella Signed-off-by: Philippe Mathieu-Daudé Message-Id: <20200821195359.1285345-9-philmd@redhat.com> Signed-off-by: Kevin Wolf --- block/nvme.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/block/nvme.c b/block/nvme.c index 0992f2fb57..b0d55ecfb2 100644 --- a/block/nvme.c +++ b/block/nvme.c @@ -508,9 +508,10 @@ static int nvme_cmd_sync(BlockDriverState *bs, NVMeQueuePair *q, static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp) { BDRVNVMeState *s = bs->opaque; - NvmeIdCtrl *idctrl; - NvmeIdNs *idns; - uint8_t *id; + union { + NvmeIdCtrl ctrl; + NvmeIdNs ns; + } *id; NvmeLBAF *lbaf; uint16_t oncs; int r; @@ -520,14 +521,12 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp) .cdw10 = cpu_to_le32(0x1), }; - id = qemu_try_blockalign0(bs, sizeof(NvmeIdCtrl)); + id = qemu_try_blockalign0(bs, sizeof(*id)); if (!id) { error_setg(errp, "Cannot allocate buffer for identify response"); goto out; } - idctrl = (NvmeIdCtrl *)id; - idns = (NvmeIdNs *)id; - r = qemu_vfio_dma_map(s->vfio, id, sizeof(NvmeIdCtrl), true, &iova); + r = qemu_vfio_dma_map(s->vfio, id, sizeof(*id), true, &iova); if (r) { error_setg(errp, "Cannot map buffer for DMA"); goto out; @@ -539,22 +538,22 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp) goto out; } - if (le32_to_cpu(idctrl->nn) < namespace) { + if (le32_to_cpu(id->ctrl.nn) < namespace) { error_setg(errp, "Invalid namespace"); goto out; } - s->write_cache_supported = le32_to_cpu(idctrl->vwc) & 0x1; - s->max_transfer = (idctrl->mdts ? 1 << idctrl->mdts : 0) * s->page_size; + s->write_cache_supported = le32_to_cpu(id->ctrl.vwc) & 0x1; + s->max_transfer = (id->ctrl.mdts ? 1 << id->ctrl.mdts : 0) * s->page_size; /* For now the page list buffer per command is one page, to hold at most * s->page_size / sizeof(uint64_t) entries. */ s->max_transfer = MIN_NON_ZERO(s->max_transfer, s->page_size / sizeof(uint64_t) * s->page_size); - oncs = le16_to_cpu(idctrl->oncs); + oncs = le16_to_cpu(id->ctrl.oncs); s->supports_write_zeroes = !!(oncs & NVME_ONCS_WRITE_ZEROES); s->supports_discard = !!(oncs & NVME_ONCS_DSM); - memset(id, 0, 4096); + memset(id, 0, sizeof(*id)); cmd.cdw10 = 0; cmd.nsid = cpu_to_le32(namespace); if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) { @@ -562,11 +561,11 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp) goto out; } - s->nsze = le64_to_cpu(idns->nsze); - lbaf = &idns->lbaf[NVME_ID_NS_FLBAS_INDEX(idns->flbas)]; + s->nsze = le64_to_cpu(id->ns.nsze); + lbaf = &id->ns.lbaf[NVME_ID_NS_FLBAS_INDEX(id->ns.flbas)]; - if (NVME_ID_NS_DLFEAT_WRITE_ZEROES(idns->dlfeat) && - NVME_ID_NS_DLFEAT_READ_BEHAVIOR(idns->dlfeat) == + if (NVME_ID_NS_DLFEAT_WRITE_ZEROES(id->ns.dlfeat) && + NVME_ID_NS_DLFEAT_READ_BEHAVIOR(id->ns.dlfeat) == NVME_ID_NS_DLFEAT_READ_BEHAVIOR_ZEROES) { bs->supported_write_flags |= BDRV_REQ_MAY_UNMAP; }