From patchwork Fri May 15 12:44:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 282648 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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 0341AC433E0 for ; Fri, 15 May 2020 13:05:44 +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 BEFA320657 for ; Fri, 15 May 2020 13:05:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="av07ypym" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BEFA320657 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]:36150 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jZa22-0006B1-Ry for qemu-devel@archiver.kernel.org; Fri, 15 May 2020 09:05:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45780) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jZZjH-00033v-0i for qemu-devel@nongnu.org; Fri, 15 May 2020 08:46:19 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:32984 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 1jZZjE-0002NI-SR for qemu-devel@nongnu.org; Fri, 15 May 2020 08:46:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589546776; 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=AuY+Dbh3/ukNTTpzfm0qDSVDwuPn80YJkfSix/LeENg=; b=av07ypymPE3DW/6f9p8bFkth1z8wilsOKwZ5719e3h9T4xM6cTWwmhbjy28SBmqGfkcMC9 wthHI0A5U/29DSQfyWdeovPpEd2qb7F2LTGFlFu8ICmLk14bSS4lmJnGnw9cc+o3HIFotI +PWe+pvPrWg52JVQrs6wAJY9FXSGN68= 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-61-yL2xoS64OnS4vVgaTaMaNQ-1; Fri, 15 May 2020 08:46:13 -0400 X-MC-Unique: yL2xoS64OnS4vVgaTaMaNQ-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 E13ED107ACF4; Fri, 15 May 2020 12:46:12 +0000 (UTC) Received: from linux.fritz.box.com (ovpn-113-110.ams2.redhat.com [10.36.113.110]) by smtp.corp.redhat.com (Postfix) with ESMTP id E85FF2E024; Fri, 15 May 2020 12:46:11 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Subject: [PULL 29/51] block: Pull out bdrv_default_perms_for_storage() Date: Fri, 15 May 2020 14:44:59 +0200 Message-Id: <20200515124521.335403-30-kwolf@redhat.com> In-Reply-To: <20200515124521.335403-1-kwolf@redhat.com> References: <20200515124521.335403-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 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 = 2020/05/14 22:56:02 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_H2=-0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Max Reitz Right now, bdrv_format_default_perms() is used by format parents (generally). We want to switch to a model where most parents use a single BdrvChildClass, which then decides the permissions based on the child role. To do so, we have to split bdrv_format_default_perms() into separate functions for each such role. Note that bdrv_default_perms_for_storage() currently handles all DATA | METADATA children. A follow-up patch is going to split it further into one function for each case. Signed-off-by: Max Reitz Reviewed-by: Eric Blake Message-Id: <20200513110544.176672-18-mreitz@redhat.com> Signed-off-by: Kevin Wolf --- block.c | 71 +++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 46 insertions(+), 25 deletions(-) diff --git a/block.c b/block.c index b12222a471..5d17aa1cc3 100644 --- a/block.c +++ b/block.c @@ -2506,6 +2506,50 @@ static void bdrv_default_perms_for_cow(BlockDriverState *bs, BdrvChild *c, *nshared = shared; } +static void bdrv_default_perms_for_storage(BlockDriverState *bs, BdrvChild *c, + const BdrvChildClass *child_class, + BdrvChildRole role, + BlockReopenQueue *reopen_queue, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + int flags; + + assert(child_class == &child_file || + (child_class == &child_of_bds && + (role & (BDRV_CHILD_METADATA | BDRV_CHILD_DATA)))); + + flags = bdrv_reopen_get_flags(reopen_queue, bs); + + /* + * Apart from the modifications below, the same permissions are + * forwarded and left alone as for filters + */ + bdrv_filter_default_perms(bs, c, child_class, role, reopen_queue, + perm, shared, &perm, &shared); + + /* Format drivers may touch metadata even if the guest doesn't write */ + if (bdrv_is_writable_after_reopen(bs, reopen_queue)) { + perm |= BLK_PERM_WRITE | BLK_PERM_RESIZE; + } + + /* + * bs->file always needs to be consistent because of the metadata. We + * can never allow other users to resize or write to it. + */ + if (!(flags & BDRV_O_NO_IO)) { + perm |= BLK_PERM_CONSISTENT_READ; + } + shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); + + if (bs->open_flags & BDRV_O_INACTIVE) { + shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; + } + + *nperm = perm; + *nshared = shared; +} + void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, const BdrvChildClass *child_class, BdrvChildRole role, @@ -2517,31 +2561,8 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, assert(child_class == &child_backing || child_class == &child_file); if (!backing) { - int flags = bdrv_reopen_get_flags(reopen_queue, bs); - - /* Apart from the modifications below, the same permissions are - * forwarded and left alone as for filters */ - bdrv_filter_default_perms(bs, c, child_class, role, reopen_queue, - perm, shared, &perm, &shared); - - /* Format drivers may touch metadata even if the guest doesn't write */ - if (bdrv_is_writable_after_reopen(bs, reopen_queue)) { - perm |= BLK_PERM_WRITE | BLK_PERM_RESIZE; - } - - /* bs->file always needs to be consistent because of the metadata. We - * can never allow other users to resize or write to it. */ - if (!(flags & BDRV_O_NO_IO)) { - perm |= BLK_PERM_CONSISTENT_READ; - } - shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); - - if (bs->open_flags & BDRV_O_INACTIVE) { - shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; - } - - *nperm = perm; - *nshared = shared; + bdrv_default_perms_for_storage(bs, c, child_class, role, reopen_queue, + perm, shared, nperm, nshared); } else { bdrv_default_perms_for_cow(bs, c, child_class, role, reopen_queue, perm, shared, nperm, nshared);