From patchwork Tue Feb 18 12:42:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 11388395 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7C00713A4 for ; Tue, 18 Feb 2020 12:56:17 +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 538B02067D for ; Tue, 18 Feb 2020 12:56:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="W1bfpiZ+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 538B02067D 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:34124 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j42QC-0001na-Fe for patchwork-qemu-devel@patchwork.kernel.org; Tue, 18 Feb 2020 07:56:16 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:39276) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j42E8-0005eV-AP for qemu-devel@nongnu.org; Tue, 18 Feb 2020 07:43:49 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j42E7-0001Xy-0g for qemu-devel@nongnu.org; Tue, 18 Feb 2020 07:43:48 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:53380 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j42E6-0001Xf-Sc for qemu-devel@nongnu.org; Tue, 18 Feb 2020 07:43:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582029826; 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=gArPcFvrgWgPAU5UnPYON1w06SOWCsg0NzSVFmmLTmI=; b=W1bfpiZ+vkgEHzpUt8WDPk39bltL/fQfP3UESByxGAc3vIhiF0SlwQWgr5b9jqc2EDdBvK wTQdDk49yYQrkZYhCmooavTU4bsu6/gW0RbEw31vSOcK5zVrmw9ldbOGnvBnPykxagd4Hr CUDiqSyrbXwjNkvj0Qx00GWnHwUiJoI= 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-97-E2tbPrHtOTyiCZhxTNASEA-1; Tue, 18 Feb 2020 07:43:38 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C5E9B18A5500; Tue, 18 Feb 2020 12:43:37 +0000 (UTC) Received: from localhost (unknown [10.36.118.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3F6A660C80; Tue, 18 Feb 2020 12:43:36 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH v3 16/33] block: Pull out bdrv_default_perms_for_storage() Date: Tue, 18 Feb 2020 13:42:25 +0100 Message-Id: <20200218124242.584644-17-mreitz@redhat.com> In-Reply-To: <20200218124242.584644-1-mreitz@redhat.com> References: <20200218124242.584644-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: E2tbPrHtOTyiCZhxTNASEA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" 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 --- block.c | 71 +++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 46 insertions(+), 25 deletions(-) diff --git a/block.c b/block.c index 8b97412cbc..64b5635122 100644 --- a/block.c +++ b/block.c @@ -2340,6 +2340,50 @@ static void bdrv_default_perms_for_backing(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, @@ -2351,31 +2395,8 @@ 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_backing(bs, c, child_class, role, reopen_queue, perm, shared, nperm, nshared);