From nobody Mon Feb 9 03:12:54 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1635264695705313.69245173325305; Tue, 26 Oct 2021 09:11:35 -0700 (PDT) Received: from localhost ([::1]:37426 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mfP30-0005gn-Kd for importer@patchew.org; Tue, 26 Oct 2021 12:11:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57722) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mfOzL-0007jG-Of for qemu-devel@nongnu.org; Tue, 26 Oct 2021 12:07:47 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:41746) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mfOzK-00044N-2H for qemu-devel@nongnu.org; Tue, 26 Oct 2021 12:07:47 -0400 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-60-sZHwZIsOPLmkrhh5dO8h6A-1; Tue, 26 Oct 2021 12:07:42 -0400 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 0AC5810168C3; Tue, 26 Oct 2021 16:07:41 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.192.183]) by smtp.corp.redhat.com (Postfix) with ESMTP id ECDB51972D; Tue, 26 Oct 2021 16:07:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1635264465; 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=zjLtlBcGj/IRcnBpCfCpWEDqyxtDvZR4R/M/lfHENw4=; b=dQjeLUigQYLV6a0LO7nG+kor+6taqSdazBaD6hq839C9hSfi4sXfLwcCq6P1WvBr8rY4rc XkTICwFrPxBN07oNwDUi8N9KzKzPFE1CwRHckqvRqeYFrrX/zdYHqAruDxF0pSPjlpL4+i MzZV+9wwTJnBx3jv3Y6QHQLOOg0mUTo= X-MC-Unique: sZHwZIsOPLmkrhh5dO8h6A-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v2 2/3] memory: Make memory_region_is_mapped() succeed when mapped via an alias Date: Tue, 26 Oct 2021 18:06:48 +0200 Message-Id: <20211026160649.47545-3-david@redhat.com> In-Reply-To: <20211026160649.47545-1-david@redhat.com> References: <20211026160649.47545-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 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-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_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: 2.1.23 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+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1635264696248100001 Content-Type: text/plain; charset="utf-8" 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. Signed-off-by: David Hildenbrand Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- include/exec/memory.h | 1 + softmmu/memory.c | 12 +++++++++++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/include/exec/memory.h b/include/exec/memory.h index a185b6dcb8..35382d9870 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -707,6 +707,7 @@ 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 e5826faa0c..17ca896c38 100644 --- a/softmmu/memory.c +++ b/softmmu/memory.c @@ -2524,8 +2524,13 @@ static void memory_region_add_subregion_common(Memor= yRegion *mr, hwaddr offset, MemoryRegion *subregion) { + MemoryRegion *alias; + assert(!subregion->container); subregion->container =3D mr; + for (alias =3D subregion->alias; alias; alias =3D alias->alias) { + alias->mapped_via_alias++; + } subregion->addr =3D offset; memory_region_update_container_subregions(subregion); } @@ -2550,9 +2555,14 @@ void memory_region_add_subregion_overlap(MemoryRegio= n *mr, void memory_region_del_subregion(MemoryRegion *mr, MemoryRegion *subregion) { + MemoryRegion *alias; + memory_region_transaction_begin(); assert(subregion->container =3D=3D mr); subregion->container =3D NULL; + for (alias =3D subregion->alias; alias; alias =3D alias->alias) { + alias->mapped_via_alias--; + } QTAILQ_REMOVE(&mr->subregions, subregion, subregions_link); memory_region_unref(subregion); memory_region_update_pending |=3D mr->enabled && subregion->enabled; @@ -2649,7 +2659,7 @@ static FlatRange *flatview_lookup(FlatView *view, Add= rRange addr) =20 bool memory_region_is_mapped(MemoryRegion *mr) { - return mr->container ? true : false; + return !!mr->container || mr->mapped_via_alias; } =20 /* Same as memory_region_find, but it does not add a reference to the --=20 2.31.1