From patchwork Wed Nov 4 17:32:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 1394433 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=LBICOmu4; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 4CRDXX67f3z9sSs for ; Thu, 5 Nov 2020 04:43:40 +1100 (AEDT) Received: from localhost ([::1]:42234 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kaMos-0006Il-Rj for incoming@patchwork.ozlabs.org; Wed, 04 Nov 2020 12:43:38 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34398) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kaMeD-0002mR-Ig for qemu-devel@nongnu.org; Wed, 04 Nov 2020 12:32:37 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:44483) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kaMeA-0000dq-Qh for qemu-devel@nongnu.org; Wed, 04 Nov 2020 12:32:37 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1604511153; 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=JAkNKONqo76aMaOLMEJtdIGjE54M7qVDn/xgaYjJzws=; b=LBICOmu40rvISEEd+ku0EALAnSfGtcsuF7O1KRjX+yJL9I9soNS8SJo9fGV1EwtSDoKsDq 1aT7SoDmIb1cI9VHJQWogT4ZU33oQ1wWe30JgW8ktYV6mRn9qZXr+ofQ/3jVQJhEeXCnWj b1cGC1OmXWcpKPFmJkvL4/eD8OxBNjY= 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-468-iVOoeJgpNtidOyQce_ZkpA-1; Wed, 04 Nov 2020 12:32:31 -0500 X-MC-Unique: iVOoeJgpNtidOyQce_ZkpA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7BFAA80476C; Wed, 4 Nov 2020 17:32:30 +0000 (UTC) Received: from localhost.localdomain (unknown [10.35.207.23]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2172075128; Wed, 4 Nov 2020 17:32:26 +0000 (UTC) From: Maxim Levitsky To: qemu-devel@nongnu.org Subject: [PATCH 1/5] file-posix: split hdev_refresh_limits from raw_refresh_limits Date: Wed, 4 Nov 2020 19:32:13 +0200 Message-Id: <20201104173217.417538-2-mlevitsk@redhat.com> In-Reply-To: <20201104173217.417538-1-mlevitsk@redhat.com> References: <20201104173217.417538-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mlevitsk@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=mlevitsk@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/03 22:09:52 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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=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: Fam Zheng , Kevin Wolf , Stefan Hajnoczi , qemu-block@nongnu.org, Peter Lieven , Tom Yan , Ronnie Sahlberg , Paolo Bonzini , Maxim Levitsky , Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Tom Yan We can and should get max transfer length and max segments for all host devices / cdroms (on Linux). Also use MIN_NON_ZERO instead when we clamp max transfer length against max segments. Signed-off-by: Tom Yan Signed-off-by: Maxim Levitsky --- block/file-posix.c | 61 ++++++++++++++++++++++++++++++++++------------ 1 file changed, 45 insertions(+), 16 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index c63926d592..6581f41b2b 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1162,6 +1162,12 @@ static void raw_reopen_abort(BDRVReopenState *state) static int sg_get_max_transfer_length(int fd) { + /* + * BLKSECTGET for /dev/sg* character devices incorrectly returns + * the max transfer size in bytes (rather than in blocks). + * Also note that /dev/sg* doesn't support BLKSSZGET ioctl. + */ + #ifdef BLKSECTGET int max_bytes = 0; @@ -1175,7 +1181,24 @@ static int sg_get_max_transfer_length(int fd) #endif } -static int sg_get_max_segments(int fd) +static int get_max_transfer_length(int fd) +{ +#if defined(BLKSECTGET) && defined(BLKSSZGET) + int sect = 0; + int ssz = 0; + + if (ioctl(fd, BLKSECTGET, §) == 0 && + ioctl(fd, BLKSSZGET, &ssz) == 0) { + return sect * ssz; + } else { + return -errno; + } +#else + return -ENOSYS; +#endif +} + +static int get_max_segments(int fd) { #ifdef CONFIG_LINUX char buf[32]; @@ -1230,23 +1253,29 @@ static void raw_refresh_limits(BlockDriverState *bs, Error **errp) { BDRVRawState *s = bs->opaque; - if (bs->sg) { - int ret = sg_get_max_transfer_length(s->fd); + raw_probe_alignment(bs, s->fd, errp); + bs->bl.min_mem_alignment = s->buf_align; + bs->bl.opt_mem_alignment = MAX(s->buf_align, qemu_real_host_page_size); +} - if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) { - bs->bl.max_transfer = pow2floor(ret); - } +static void hdev_refresh_limits(BlockDriverState *bs, Error **errp) +{ + BDRVRawState *s = bs->opaque; - ret = sg_get_max_segments(s->fd); - if (ret > 0) { - bs->bl.max_transfer = MIN(bs->bl.max_transfer, - ret * qemu_real_host_page_size); - } + int ret = bs->sg ? sg_get_max_transfer_length(s->fd) : + get_max_transfer_length(s->fd); + + if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) { + bs->bl.max_transfer = pow2floor(ret); } - raw_probe_alignment(bs, s->fd, errp); - bs->bl.min_mem_alignment = s->buf_align; - bs->bl.opt_mem_alignment = MAX(s->buf_align, qemu_real_host_page_size); + ret = get_max_segments(s->fd); + if (ret > 0) { + bs->bl.max_transfer = MIN_NON_ZERO(bs->bl.max_transfer, + ret * qemu_real_host_page_size); + } + + raw_refresh_limits(bs, errp); } static int check_for_dasd(int fd) @@ -3600,7 +3629,7 @@ static BlockDriver bdrv_host_device = { .bdrv_co_pdiscard = hdev_co_pdiscard, .bdrv_co_copy_range_from = raw_co_copy_range_from, .bdrv_co_copy_range_to = raw_co_copy_range_to, - .bdrv_refresh_limits = raw_refresh_limits, + .bdrv_refresh_limits = hdev_refresh_limits, .bdrv_io_plug = raw_aio_plug, .bdrv_io_unplug = raw_aio_unplug, .bdrv_attach_aio_context = raw_aio_attach_aio_context, @@ -3724,7 +3753,7 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_co_preadv = raw_co_preadv, .bdrv_co_pwritev = raw_co_pwritev, .bdrv_co_flush_to_disk = raw_co_flush_to_disk, - .bdrv_refresh_limits = raw_refresh_limits, + .bdrv_refresh_limits = hdev_refresh_limits, .bdrv_io_plug = raw_aio_plug, .bdrv_io_unplug = raw_aio_unplug, .bdrv_attach_aio_context = raw_aio_attach_aio_context,