From patchwork Thu Aug 12 08:41:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 12432907 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=-13.5 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,URIBL_BLOCKED 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 8F81FC4338F for ; Thu, 12 Aug 2021 08:45:38 +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 0EF566103A for ; Thu, 12 Aug 2021 08:45:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0EF566103A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:46018 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mE6LI-0004ag-Tr for qemu-devel@archiver.kernel.org; Thu, 12 Aug 2021 04:45:36 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35624) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mE6Ht-0004ig-A8 for qemu-devel@nongnu.org; Thu, 12 Aug 2021 04:42:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:28601) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mE6Hr-0004lL-UG for qemu-devel@nongnu.org; Thu, 12 Aug 2021 04:42:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628757723; 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=A7OBgZ5Pa9IACALRG26Pb/1nfqyFwvc0iacl8KZexbA=; b=Z/h7cpQJifnZk7eqJQjc6A1WhNLd3hKn86JqmyuC3FsMlntdfOk+2cfEqnmWjKWchVbPIn UEJXmmNHpwvjr61pUiEtB5ZSVfqc1EquA2SL8Ihigpgv+DmpWYvjH47qt+iRuCL0BVMvOA TKg/p1WL5DbJptFoUp8zXMsCtP0nrfo= 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-123-ChQVl_Z5Pu6MYiyroT5HUA-1; Thu, 12 Aug 2021 04:42:00 -0400 X-MC-Unique: ChQVl_Z5Pu6MYiyroT5HUA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E37B687D542; Thu, 12 Aug 2021 08:41:58 +0000 (UTC) Received: from localhost (unknown [10.39.193.89]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8BC845C23A; Thu, 12 Aug 2021 08:41:58 +0000 (UTC) From: Hanna Reitz To: qemu-block@nongnu.org Subject: [PATCH v3 4/6] block/file-posix: Do not force-cap *pnum Date: Thu, 12 Aug 2021 10:41:46 +0200 Message-Id: <20210812084148.14458-5-hreitz@redhat.com> In-Reply-To: <20210812084148.14458-1-hreitz@redhat.com> References: <20210812084148.14458-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=hreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.7, 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_H2=-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 , Hanna Reitz , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org 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: Hanna Reitz Reviewed-by: Eric Blake Reviewed-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Kevin Wolf --- 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 cb9bffe047..9f35e5631a 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -2744,7 +2744,8 @@ 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, @@ -2782,7 +2783,7 @@ 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 @@ -2801,7 +2802,7 @@ 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;