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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 52314C433F5 for ; Tue, 1 Feb 2022 20:44:54 +0000 (UTC) Received: from localhost ([::1]:43946 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nF01F-0003d0-7T for qemu-devel@archiver.kernel.org; Tue, 01 Feb 2022 15:44:53 -0500 Received: from eggs.gnu.org ([209.51.188.92]:58094) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nEwx6-0001JZ-5P for qemu-devel@nongnu.org; Tue, 01 Feb 2022 12:28:24 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:50436) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nEwx3-0000Go-1p for qemu-devel@nongnu.org; Tue, 01 Feb 2022 12:28:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643736481; 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=uJGuFdBHy4gqarPpquFAw1Wj7Q9CqhmbQt+C2TQ9gu8=; b=I9xl4s1+1hI1OW/xAigjmxWLD+JIDqFIEXJgLFxAiTyJ09IDIvm6mSv5EWvpiwP9vzR5m/ rZ8WlhFEf+4NotwaxASw4sSYJlog6L9r/a5KwZKOAnUWvVkvH+XWn/3VMJi7745uIzEy8H IMckRF1QE8qEov/wHzI0kAPeV2K53Pk= Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-479-xIcud4--OdOAX-Aff7lhvw-1; Tue, 01 Feb 2022 12:28:00 -0500 X-MC-Unique: xIcud4--OdOAX-Aff7lhvw-1 Received: by mail-qt1-f199.google.com with SMTP id a28-20020ac84d9c000000b002d05c958a84so13516790qtw.0 for ; Tue, 01 Feb 2022 09:28:00 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=uJGuFdBHy4gqarPpquFAw1Wj7Q9CqhmbQt+C2TQ9gu8=; b=NNEeQgUU5MvetqzZOASHmC2hJMGbrDLtxvWrVBSxAEf2xvn41yRwaNk+E7BYJHVQ/q aPVgYneat2wEb1dwl9y/sgpK4eNW+UXGgsDwa8Y3Tv9uz9wNYUEF+yEOAUU/6Xquf4Vd 5LF+HyPAzRzS1ZXEm60FYLrK4AliTNrQBfRh8ydJVJjCGT3NBmdowQVuuyuo2QPGWK8/ 8R0VYvHx4Zi4VgJGkDbR9qugq5e/+S0Vf/v5j1XkzC69B7+RxdaRXw8SfjGzd008o6YE v/le7Sou7AN2yL/yW8rRKZmb0de60hf3da/CyR5+5ac3dpOCz9yWwuRVAtJ6G6JeSYMy OfJw== X-Gm-Message-State: AOAM530sfdOs8TTdqhQzFGPwc6RFblbaWbE+BO16t/genP5i355EFDNX U4lpR6n7Ymd11z7YDPxfA+p07wh/uJ1MnGep9o7sBrxCfUXKVFdSYB7sz8eWT2+lgGXHecbWAJf XtuLF+3ntE6Pbabkoy53ietBsM6onyec= X-Received: by 2002:ac8:5a4a:: with SMTP id o10mr3533160qta.459.1643736478346; Tue, 01 Feb 2022 09:27:58 -0800 (PST) X-Google-Smtp-Source: ABdhPJzU5S3HNjxQxWfnfr/qjnHncr/D8lNm1aQE/dZPc0Mw8IuWDwkOe/pzeseqdjbFv3f0hUFKPnbFHVC9tL2r6f8= X-Received: by 2002:ac8:5a4a:: with SMTP id o10mr3533142qta.459.1643736478072; Tue, 01 Feb 2022 09:27:58 -0800 (PST) MIME-Version: 1.0 References: <20220121202733.404989-1-eperezma@redhat.com> <20220121202733.404989-23-eperezma@redhat.com> <2eb07526-0143-d612-8969-097ccdf00fae@redhat.com> In-Reply-To: <2eb07526-0143-d612-8969-097ccdf00fae@redhat.com> From: Eugenio Perez Martin Date: Tue, 1 Feb 2022 18:27:21 +0100 Message-ID: Subject: Re: [PATCH 22/31] vhost: Add VhostIOVATree To: Jason Wang Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eperezma@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=170.10.129.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.081, 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, T_SCC_BODY_TEXT_LINE=-0.01 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: Laurent Vivier , Parav Pandit , Cindy Lu , "Michael S. Tsirkin" , Juan Quintela , Richard Henderson , qemu-level , Gautam Dawar , Markus Armbruster , Eduardo Habkost , Harpreet Singh Anand , Xiao W Wang , Peter Xu , Stefan Hajnoczi , Eli Cohen , Paolo Bonzini , Zhu Lingshan , virtualization , Eric Blake , Stefano Garzarella Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Sun, Jan 30, 2022 at 6:21 AM Jason Wang wrote: > > > =E5=9C=A8 2022/1/22 =E4=B8=8A=E5=8D=884:27, Eugenio P=C3=A9rez =E5=86=99= =E9=81=93: > > This tree is able to look for a translated address from an IOVA address= . > > > > At first glance it is similar to util/iova-tree. However, SVQ working o= n > > devices with limited IOVA space need more capabilities, > > > So did the IOVA tree (e.g l2 vtd can only work in the range of GAW and > without RMRRs). > > > > like allocating > > IOVA chunks or performing reverse translations (qemu addresses to iova)= . > > > This looks like a general request as well. So I wonder if we can simply > extend iova tree instead. > While both are true, I don't see code that performs allocations or qemu vaddr to iova translations. But if the changes can be integrated into iova-tree that would be great for sure. The main drawback I see is the need to maintain two trees instead of one for users of iova-tree. While complexity does not grow, it needs to double the amount of work needed. Thanks! > Thanks > > > > > > The allocation capability, as "assign a free IOVA address to this chunk > > of memory in qemu's address space" allows shadow virtqueue to create a > > new address space that is not restricted by guest's addressable one, so > > we can allocate shadow vqs vrings outside of it. > > > > It duplicates the tree so it can search efficiently both directions, > > and it will signal overlap if iova or the translated address is > > present in any tree. > > > > Signed-off-by: Eugenio P=C3=A9rez > > --- > > hw/virtio/vhost-iova-tree.h | 27 +++++++ > > hw/virtio/vhost-iova-tree.c | 157 +++++++++++++++++++++++++++++++++++= + > > hw/virtio/meson.build | 2 +- > > 3 files changed, 185 insertions(+), 1 deletion(-) > > create mode 100644 hw/virtio/vhost-iova-tree.h > > create mode 100644 hw/virtio/vhost-iova-tree.c > > > > diff --git a/hw/virtio/vhost-iova-tree.h b/hw/virtio/vhost-iova-tree.h > > new file mode 100644 > > index 0000000000..610394eaf1 > > --- /dev/null > > +++ b/hw/virtio/vhost-iova-tree.h > > @@ -0,0 +1,27 @@ > > +/* > > + * vhost software live migration ring > > + * > > + * SPDX-FileCopyrightText: Red Hat, Inc. 2021 > > + * SPDX-FileContributor: Author: Eugenio P=C3=A9rez > > + * > > + * SPDX-License-Identifier: GPL-2.0-or-later > > + */ > > + > > +#ifndef HW_VIRTIO_VHOST_IOVA_TREE_H > > +#define HW_VIRTIO_VHOST_IOVA_TREE_H > > + > > +#include "qemu/iova-tree.h" > > +#include "exec/memory.h" > > + > > +typedef struct VhostIOVATree VhostIOVATree; > > + > > +VhostIOVATree *vhost_iova_tree_new(uint64_t iova_first, uint64_t iova_= last); > > +void vhost_iova_tree_delete(VhostIOVATree *iova_tree); > > +G_DEFINE_AUTOPTR_CLEANUP_FUNC(VhostIOVATree, vhost_iova_tree_delete); > > + > > +const DMAMap *vhost_iova_tree_find_iova(const VhostIOVATree *iova_tree= , > > + const DMAMap *map); > > +int vhost_iova_tree_map_alloc(VhostIOVATree *iova_tree, DMAMap *map); > > +void vhost_iova_tree_remove(VhostIOVATree *iova_tree, const DMAMap *ma= p); > > + > > +#endif > > diff --git a/hw/virtio/vhost-iova-tree.c b/hw/virtio/vhost-iova-tree.c > > new file mode 100644 > > index 0000000000..0021dbaf54 > > --- /dev/null > > +++ b/hw/virtio/vhost-iova-tree.c > > @@ -0,0 +1,157 @@ > > +/* > > + * vhost software live migration ring > > + * > > + * SPDX-FileCopyrightText: Red Hat, Inc. 2021 > > + * SPDX-FileContributor: Author: Eugenio P=C3=A9rez > > + * > > + * SPDX-License-Identifier: GPL-2.0-or-later > > + */ > > + > > +#include "qemu/osdep.h" > > +#include "qemu/iova-tree.h" > > +#include "vhost-iova-tree.h" > > + > > +#define iova_min_addr qemu_real_host_page_size > > + > > +/** > > + * VhostIOVATree, able to: > > + * - Translate iova address > > + * - Reverse translate iova address (from translated to iova) > > + * - Allocate IOVA regions for translated range (potentially slow oper= ation) > > + * > > + * Note that it cannot remove nodes. > > + */ > > +struct VhostIOVATree { > > + /* First addresable iova address in the device */ > > + uint64_t iova_first; > > + > > + /* Last addressable iova address in the device */ > > + uint64_t iova_last; > > + > > + /* IOVA address to qemu memory maps. */ > > + IOVATree *iova_taddr_map; > > + > > + /* QEMU virtual memory address to iova maps */ > > + GTree *taddr_iova_map; > > +}; > > + > > +static gint vhost_iova_tree_cmp_taddr(gconstpointer a, gconstpointer b= , > > + gpointer data) > > +{ > > + const DMAMap *m1 =3D a, *m2 =3D b; > > + > > + if (m1->translated_addr > m2->translated_addr + m2->size) { > > + return 1; > > + } > > + > > + if (m1->translated_addr + m1->size < m2->translated_addr) { > > + return -1; > > + } > > + > > + /* Overlapped */ > > + return 0; > > +} > > + > > +/** > > + * Create a new IOVA tree > > + * > > + * Returns the new IOVA tree > > + */ > > +VhostIOVATree *vhost_iova_tree_new(hwaddr iova_first, hwaddr iova_last= ) > > +{ > > + VhostIOVATree *tree =3D g_new(VhostIOVATree, 1); > > + > > + /* Some devices does not like 0 addresses */ > > + tree->iova_first =3D MAX(iova_first, iova_min_addr); > > + tree->iova_last =3D iova_last; > > + > > + tree->iova_taddr_map =3D iova_tree_new(); > > + tree->taddr_iova_map =3D g_tree_new_full(vhost_iova_tree_cmp_taddr= , NULL, > > + NULL, g_free); > > + return tree; > > +} > > + > > +/** > > + * Delete an iova tree > > + */ > > +void vhost_iova_tree_delete(VhostIOVATree *iova_tree) > > +{ > > + iova_tree_destroy(iova_tree->iova_taddr_map); > > + g_tree_unref(iova_tree->taddr_iova_map); > > + g_free(iova_tree); > > +} > > + > > +/** > > + * Find the IOVA address stored from a memory address > > + * > > + * @tree The iova tree > > + * @map The map with the memory address > > + * > > + * Return the stored mapping, or NULL if not found. > > + */ > > +const DMAMap *vhost_iova_tree_find_iova(const VhostIOVATree *tree, > > + const DMAMap *map) > > +{ > > + return g_tree_lookup(tree->taddr_iova_map, map); > > +} > > + > > +/** > > + * Allocate a new mapping > > + * > > + * @tree The iova tree > > + * @map The iova map > > + * > > + * Returns: > > + * - IOVA_OK if the map fits in the container > > + * - IOVA_ERR_INVALID if the map does not make sense (like size overfl= ow) > > + * - IOVA_ERR_OVERLAP if the tree already contains that map > > + * - IOVA_ERR_NOMEM if tree cannot allocate more space. > > + * > > + * It returns assignated iova in map->iova if return value is VHOST_DM= A_MAP_OK. > > + */ > > +int vhost_iova_tree_map_alloc(VhostIOVATree *tree, DMAMap *map) > > +{ > > + /* Some vhost devices does not like addr 0. Skip first page */ > > + hwaddr iova_first =3D tree->iova_first ?: qemu_real_host_page_size= ; > > + DMAMap *new; > > + int r; > > + > > + if (map->translated_addr + map->size < map->translated_addr || > > + map->perm =3D=3D IOMMU_NONE) { > > + return IOVA_ERR_INVALID; > > + } > > + > > + /* Check for collisions in translated addresses */ > > + if (vhost_iova_tree_find_iova(tree, map)) { > > + return IOVA_ERR_OVERLAP; > > + } > > + > > + /* Allocate a node in IOVA address */ > > + r =3D iova_tree_alloc(tree->iova_taddr_map, map, iova_first, > > + tree->iova_last); > > + if (r !=3D IOVA_OK) { > > + return r; > > + } > > + > > + /* Allocate node in qemu -> iova translations */ > > + new =3D g_malloc(sizeof(*new)); > > + memcpy(new, map, sizeof(*new)); > > + g_tree_insert(tree->taddr_iova_map, new, new); > > + return IOVA_OK; > > +} > > + > > +/** > > + * Remove existing mappings from iova tree > > + * > > + * @param iova_tree The vhost iova tree > > + * @param map The map to remove > > + */ > > +void vhost_iova_tree_remove(VhostIOVATree *iova_tree, const DMAMap *ma= p) > > +{ > > + const DMAMap *overlap; > > + > > + iova_tree_remove(iova_tree->iova_taddr_map, map); > > + while ((overlap =3D vhost_iova_tree_find_iova(iova_tree, map))) { > > + g_tree_remove(iova_tree->taddr_iova_map, overlap); > > + } > > +} > > diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build > > index 2dc87613bc..6047670804 100644 > > --- a/hw/virtio/meson.build > > +++ b/hw/virtio/meson.build > > @@ -11,7 +11,7 @@ softmmu_ss.add(when: 'CONFIG_ALL', if_true: files('vh= ost-stub.c')) > > > > virtio_ss =3D ss.source_set() > > virtio_ss.add(files('virtio.c')) > > -virtio_ss.add(when: 'CONFIG_VHOST', if_true: files('vhost.c', 'vhost-b= ackend.c', 'vhost-shadow-virtqueue.c')) > > +virtio_ss.add(when: 'CONFIG_VHOST', if_true: files('vhost.c', 'vhost-b= ackend.c', 'vhost-shadow-virtqueue.c', 'vhost-iova-tree.c')) > > virtio_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user.c= ')) > > virtio_ss.add(when: 'CONFIG_VHOST_VDPA', if_true: files('vhost-vdpa.c= ')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_BALLOON', if_true: files('virtio-b= alloon.c')) >