From patchwork Thu Dec 17 16:56:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 11980227 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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 959CBC4361B for ; Thu, 17 Dec 2020 16:59:09 +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 177D9233A0 for ; Thu, 17 Dec 2020 16:59:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 177D9233A0 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]:48738 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kpwcN-0004cS-SP for qemu-devel@archiver.kernel.org; Thu, 17 Dec 2020 11:59:07 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34148) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kpwaB-0003Ap-VJ for qemu-devel@nongnu.org; Thu, 17 Dec 2020 11:56:52 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:35949) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kpwZs-0002zE-RB for qemu-devel@nongnu.org; Thu, 17 Dec 2020 11:56:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1608224191; 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=kZFEbwr1Avouyzp/6NUQgRq517wGVME+gmVK7SGUO+A=; b=JsXRunGsjtcJ/y5RR7JwEH2IpAOHuUGijUTLagrkjuWd2nYsQLUOSP6FigdWJzbssjL2wo VGdaI06X54kbAsEk+dTCcLr7F0QzR6pZz98FFziN16KvPzLXS0c7GzBp4EeHNPWh17kGG4 3AUxrZeFuxDvollc7GLEIh+Z+IBTP10= 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-24-6Dj63fEfNSyNsrKKglUjXA-1; Thu, 17 Dec 2020 11:56:27 -0500 X-MC-Unique: 6Dj63fEfNSyNsrKKglUjXA-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 95E9A101AFB0; Thu, 17 Dec 2020 16:56:25 +0000 (UTC) Received: from localhost.localdomain (unknown [10.35.206.213]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2C1591F055; Thu, 17 Dec 2020 16:56:21 +0000 (UTC) From: Maxim Levitsky To: qemu-devel@nongnu.org Subject: [PATCH v3 1/5] file-posix: split hdev_refresh_limits from raw_refresh_limits Date: Thu, 17 Dec 2020 18:56:08 +0200 Message-Id: <20201217165612.942849-2-mlevitsk@redhat.com> In-Reply-To: <20201217165612.942849-1-mlevitsk@redhat.com> References: <20201217165612.942849-1-mlevitsk@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=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-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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, T_SPF_TEMPERROR=0.01 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 , Ronnie Sahlberg , qemu-block@nongnu.org, Peter Lieven , Tom Yan , Stefan Hajnoczi , Paolo Bonzini , Maxim Levitsky , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.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 | 57 +++++++++++++++++++++++++++++++++------------- 1 file changed, 41 insertions(+), 16 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 9804681d5c..cbf1271773 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1166,6 +1166,10 @@ static int sg_get_max_transfer_length(int fd) int max_bytes = 0; if (ioctl(fd, BLKSECTGET, &max_bytes) == 0) { + /* + * BLKSECTGET for /dev/sg* character devices incorrectly returns + * the max transfer size in bytes (rather than in blocks). + */ return max_bytes; } else { return -errno; @@ -1175,7 +1179,22 @@ 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) + int sect = 0; + + if (ioctl(fd, BLKSECTGET, §) == 0) { + return sect << 9; + } else { + return -errno; + } +#else + return -ENOSYS; +#endif +} + +static int get_max_segments(int fd) { #ifdef CONFIG_LINUX char buf[32]; @@ -1230,23 +1249,29 @@ 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); +} + +static void hdev_refresh_limits(BlockDriverState *bs, Error **errp) +{ + BDRVRawState *s = bs->opaque; + + 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); - } + if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) { + bs->bl.max_transfer = pow2floor(ret); + } - 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); - } + 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_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); + raw_refresh_limits(bs, errp); } static int check_for_dasd(int fd) @@ -3600,7 +3625,7 @@ 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 +3749,7 @@ 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,