From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65B23C433EF for ; Tue, 5 Oct 2021 14:59:51 +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 F16EB61244 for ; Tue, 5 Oct 2021 14:59:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org F16EB61244 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]:45346 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mXlv2-0005KF-T5 for qemu-devel@archiver.kernel.org; Tue, 05 Oct 2021 10:59:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53834) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXlY1-0004fb-Vs for qemu-devel@nongnu.org; Tue, 05 Oct 2021 10:36:02 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:57980) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXlXv-0005WP-TV for qemu-devel@nongnu.org; Tue, 05 Oct 2021 10:36:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1633444555; 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=l96+gyHamARpqL9o+1xsA/DMOsEDvMBK7/u8XMNDR2c=; b=eern96IU1UDXyew1fnIWaSQXLlkkAcaqc4AllggJt+lMVfEzewmJ8RlUnm3J5pBWiTcfy4 6gmTPc8G0Sipfr3hFRCmnC4BwIpRQD4VXGYSw1zO2lEcEJRV2gQdOCVuVIxVfgAec/n5MT F/aqqYozirGbRGSPjo9+poXtvDCjnoA= 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-3-ye7NiKicOWS_HZKAi8_kjA-1; Tue, 05 Oct 2021 10:35:53 -0400 X-MC-Unique: ye7NiKicOWS_HZKAi8_kjA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 19B04362FE; Tue, 5 Oct 2021 14:35:52 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 83E241042AAA; Tue, 5 Oct 2021 14:35:49 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Subject: [RFC PATCH v2 23/25] block-backend-common.h: split function pointers in BlockDevOps Date: Tue, 5 Oct 2021 10:32:13 -0400 Message-Id: <20211005143215.29500-24-eesposit@redhat.com> In-Reply-To: <20211005143215.29500-1-eesposit@redhat.com> References: <20211005143215.29500-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eesposit@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=170.10.129.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -9 X-Spam_score: -1.0 X-Spam_bar: - X-Spam_report: (-1.0 / 5.0 requ) DKIMWL_WL_HIGH=-0.066, 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=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 , Vladimir Sementsov-Ogievskiy , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Eduardo Habkost , Juan Quintela , qemu-devel@nongnu.org, John Snow , Emanuele Giuseppe Esposito , Richard Henderson , Markus Armbruster , "Dr. David Alan Gilbert" , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Eric Blake Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Assertions in the callers of the funciton pointrs are already added by previous patches. Signed-off-by: Emanuele Giuseppe Esposito --- include/sysemu/block-backend-common.h | 42 +++++++++++++++++++++++---- 1 file changed, 37 insertions(+), 5 deletions(-) diff --git a/include/sysemu/block-backend-common.h b/include/sysemu/block-backend-common.h index 52ff6a4d26..25f34917b6 100644 --- a/include/sysemu/block-backend-common.h +++ b/include/sysemu/block-backend-common.h @@ -17,6 +17,29 @@ /* Callbacks for block device models */ typedef struct BlockDevOps { + + /* + * Global state (GS) API. These functions run under the BQL lock. + * + * If a function modifies the graph, it also uses drain and/or + * aio_context_acquire/release to be sure it has unique access. + * aio_context locking is needed together with BQL because of + * the thread-safe I/O API that concurrently runs and accesses + * the graph without the BQL. + * + * It is important to note that not all of these functions are + * necessarily limited to running under the BQL, but they would + * require additional auditing and may small thread-safety changes + * to move them into the I/O API. Often it's not worth doing that + * work since the APIs are only used with the BQL held at the + * moment, so they have been placed in the GS API (for now). + * + * All bdrv_* callers that use these function pointers must + * use this assertion: + * g_assert(qemu_in_main_thread()); + * to catch when they are accidentally called without the BQL. + */ + /* * Runs when virtual media changed (monitor commands eject, change) * Argument load is true on load and false on eject. @@ -34,16 +57,25 @@ typedef struct BlockDevOps { * true, even if they do not support eject requests. */ void (*eject_request_cb)(void *opaque, bool force); - /* - * Is the virtual tray open? - * Device models implement this only when the device has a tray. - */ - bool (*is_tray_open)(void *opaque); + /* * Is the virtual medium locked into the device? * Device models implement this only when device has such a lock. */ bool (*is_medium_locked)(void *opaque); + + /* + * I/O API functions. These functions are thread-safe, and therefore + * can run in any thread as long as they have called + * aio_context_acquire/release(). + */ + + /* + * Is the virtual tray open? + * Device models implement this only when the device has a tray. + */ + bool (*is_tray_open)(void *opaque); + /* * Runs when the size changed (e.g. monitor command block_resize) */ -- 2.27.0