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 177BCC43217 for ; Tue, 2 Nov 2021 16:48:22 +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 D19A360F58 for ; Tue, 2 Nov 2021 16:48:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org D19A360F58 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]:54354 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mhwxR-0001kV-0p for qemu-devel@archiver.kernel.org; Tue, 02 Nov 2021 12:48:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37880) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mhwut-0006t0-8s for qemu-devel@nongnu.org; Tue, 02 Nov 2021 12:45:43 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:43757) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mhwuq-00056a-PH for qemu-devel@nongnu.org; Tue, 02 Nov 2021 12:45:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1635871539; 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=X4hchrxwCsRo/Xfw/XJx+BgHd8p2GwZA7aQLxDcQKGs=; b=jUa5wQlkRa5Zkk4T8tRrLnQAi0AK9XGG+A4J9i2IAfcGVh0flkrFhfOixIYPAooNpfNOTq RpBljY2NOrtBhHS7QvsiBOZPkGwL5eoOLp36RrghFqxNhCz9IMd4SquPVeGy7+VdCLmYPJ 5P/Fd8A1XbcvNE19h5WEFjgIuwfmtF4= 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-601-qKCBdH49PJSseZrvL_QZkg-1; Tue, 02 Nov 2021 12:45:38 -0400 X-MC-Unique: qKCBdH49PJSseZrvL_QZkg-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 49AB0100738D; Tue, 2 Nov 2021 16:45:37 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.193.156]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9909A101E59D; Tue, 2 Nov 2021 16:45:24 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 2/3] memory: Make memory_region_is_mapped() succeed when mapped via an alias Date: Tue, 2 Nov 2021 17:43:16 +0100 Message-Id: <20211102164317.45658-3-david@redhat.com> In-Reply-To: <20211102164317.45658-1-david@redhat.com> References: <20211102164317.45658-1-david@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=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=david@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=-0.702, 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=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , David Hildenbrand , Richard Henderson , Peter Xu , Igor Mammedov , Paolo Bonzini , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" memory_region_is_mapped() currently does not return "true" when a memory region is mapped via an alias. Assuming we have: alias (A0) -> alias (A1) -> region (R0) Mapping A0 would currently only make memory_region_is_mapped() succeed on A0, but not on A1 and R0. Let's fix that by adding a "mapped_via_alias" counter to memory regions and updating it accordingly when an alias gets (un)mapped. I am not aware of actual issues, this is rather a cleanup to make it consistent. Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Peter Xu Signed-off-by: David Hildenbrand --- include/exec/memory.h | 1 + softmmu/memory.c | 13 ++++++++++++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/include/exec/memory.h b/include/exec/memory.h index 20f1b27377..fea1a493b9 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -738,6 +738,7 @@ struct MemoryRegion { const MemoryRegionOps *ops; void *opaque; MemoryRegion *container; + int mapped_via_alias; /* Mapped via an alias, container might be NULL */ Int128 size; hwaddr addr; void (*destructor)(MemoryRegion *mr); diff --git a/softmmu/memory.c b/softmmu/memory.c index 7340e19ff5..b52b6a2f66 100644 --- a/softmmu/memory.c +++ b/softmmu/memory.c @@ -2535,8 +2535,13 @@ static void memory_region_add_subregion_common(MemoryRegion *mr, hwaddr offset, MemoryRegion *subregion) { + MemoryRegion *alias; + assert(!subregion->container); subregion->container = mr; + for (alias = subregion->alias; alias; alias = alias->alias) { + alias->mapped_via_alias++; + } subregion->addr = offset; memory_region_update_container_subregions(subregion); } @@ -2561,9 +2566,15 @@ void memory_region_add_subregion_overlap(MemoryRegion *mr, void memory_region_del_subregion(MemoryRegion *mr, MemoryRegion *subregion) { + MemoryRegion *alias; + memory_region_transaction_begin(); assert(subregion->container == mr); subregion->container = NULL; + for (alias = subregion->alias; alias; alias = alias->alias) { + alias->mapped_via_alias--; + assert(alias->mapped_via_alias >= 0); + } QTAILQ_REMOVE(&mr->subregions, subregion, subregions_link); memory_region_unref(subregion); memory_region_update_pending |= mr->enabled && subregion->enabled; @@ -2660,7 +2671,7 @@ static FlatRange *flatview_lookup(FlatView *view, AddrRange addr) bool memory_region_is_mapped(MemoryRegion *mr) { - return mr->container ? true : false; + return !!mr->container || mr->mapped_via_alias; } /* Same as memory_region_find, but it does not add a reference to the -- 2.31.1