From patchwork Thu Jun 17 15:52:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 12328269 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 BE78BC2B9F4 for ; Thu, 17 Jun 2021 15:59:13 +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 5E3F061003 for ; Thu, 17 Jun 2021 15:59:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5E3F061003 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]:46466 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ltuQC-0001do-IF for qemu-devel@archiver.kernel.org; Thu, 17 Jun 2021 11:59:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43802) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ltuKC-0005Zx-5t for qemu-devel@nongnu.org; Thu, 17 Jun 2021 11:53:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:50503) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ltuKA-0001Gw-CM for qemu-devel@nongnu.org; Thu, 17 Jun 2021 11:52:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623945177; 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=AYqtM2qJIAUaOJRMjffIELPUPqFhJKPW2pkh7BPmLGM=; b=QvJRON0ujA6BMGwJB55q6Czcd/9ZYYavTEIY4sh2xJ/9bm+hcMWMNipUFx9tNcDMqPAY1b aaa2FHyffRpGoRaeYOwo96YVAQZ9Le44c880fIQc8V33SDN4FecFlUfIL8egnPlo83D5Af eAN91w0GQXNrwC9IH7UgX61PLGEtJW4= 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-523-QN2FDTjNOTypZYUHyuK7HQ-1; Thu, 17 Jun 2021 11:52:56 -0400 X-MC-Unique: QN2FDTjNOTypZYUHyuK7HQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5CCD28042B7; Thu, 17 Jun 2021 15:52:55 +0000 (UTC) Received: from localhost (ovpn-114-231.ams2.redhat.com [10.36.114.231]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0827860875; Thu, 17 Jun 2021 15:52:54 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH 3/6] block/file-posix: Do not force-cap *pnum Date: Thu, 17 Jun 2021 17:52:44 +0200 Message-Id: <20210617155247.442150-4-mreitz@redhat.com> In-Reply-To: <20210617155247.442150-1-mreitz@redhat.com> References: <20210617155247.442150-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.197, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=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: Kevin Wolf , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" bdrv_co_block_status() does it for us, we do not need to do it here. The advantage of not capping *pnum is that bdrv_co_block_status() can cache larger data regions than requested by its caller. Signed-off-by: Max Reitz Reviewed-by: Eric Blake Reviewed-by: Vladimir Sementsov-Ogievskiy --- block/file-posix.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index b3fbb9bd63..aeb370d5bb 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -2689,7 +2689,8 @@ static int find_allocation(BlockDriverState *bs, off_t start, * the specified offset) that are known to be in the same * allocated/unallocated state. * - * 'bytes' is the max value 'pnum' should be set to. + * 'bytes' is a soft cap for 'pnum'. If the information is free, 'pnum' may + * well exceed it. */ static int coroutine_fn raw_co_block_status(BlockDriverState *bs, bool want_zero, @@ -2727,7 +2728,7 @@ static int coroutine_fn raw_co_block_status(BlockDriverState *bs, } else if (data == offset) { /* On a data extent, compute bytes to the end of the extent, * possibly including a partial sector at EOF. */ - *pnum = MIN(bytes, hole - offset); + *pnum = hole - offset; /* * We are not allowed to return partial sectors, though, so @@ -2746,7 +2747,7 @@ static int coroutine_fn raw_co_block_status(BlockDriverState *bs, } else { /* On a hole, compute bytes to the beginning of the next extent. */ assert(hole == offset); - *pnum = MIN(bytes, data - offset); + *pnum = data - offset; ret = BDRV_BLOCK_ZERO; } *map = offset;