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 X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60C89C38A24 for ; Thu, 7 May 2020 14:03:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 20E5D20838 for ; Thu, 7 May 2020 14:03:42 +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="YaTA1piM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 20E5D20838 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C7872900004; Thu, 7 May 2020 10:03:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C4EDE900002; Thu, 7 May 2020 10:03:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B8ABB900004; Thu, 7 May 2020 10:03:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0209.hostedemail.com [216.40.44.209]) by kanga.kvack.org (Postfix) with ESMTP id 9E9A7900002 for ; Thu, 7 May 2020 10:03:41 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4E284180ACF9A for ; Thu, 7 May 2020 14:03:41 +0000 (UTC) X-FDA: 76790091042.29.songs85_2023501074545 X-HE-Tag: songs85_2023501074545 X-Filterd-Recvd-Size: 6173 Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Thu, 7 May 2020 14:03:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588860220; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6V2gf0PUPPm7OaaYKcNrW48UHq1Rnm4/NYm4dg9LwpA=; b=YaTA1piMohpkrVTQ47Risp9w3l5TBMhOfFmVyEacHiA5UO4tIqjJ159YYeIY5tW8tpQJBt neVvejblzPzGnpHvEgnyXn+vVkrr9Wf4BNMXhNdrlxSyC7pqiEPjpmVWpjOhZz9eH11Dzv LhbD50Cej24TBNv9RlYdfTT5F2igVYQ= 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-34-qIHWr591MXiJlBlN5gcBKg-1; Thu, 07 May 2020 10:03:35 -0400 X-MC-Unique: qIHWr591MXiJlBlN5gcBKg-1 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 35E8D80B724; Thu, 7 May 2020 14:03:34 +0000 (UTC) Received: from t480s.redhat.com (ovpn-113-245.ams2.redhat.com [10.36.113.245]) by smtp.corp.redhat.com (Postfix) with ESMTP id BF27360BEC; Thu, 7 May 2020 14:03:26 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, Michal Hocko , Andrew Morton , "Michael S . Tsirkin" , David Hildenbrand , Pankaj Gupta Subject: [PATCH v4 11/15] virtio-mem: Add parent resource for all added "System RAM" Date: Thu, 7 May 2020 16:01:35 +0200 Message-Id: <20200507140139.17083-12-david@redhat.com> In-Reply-To: <20200507140139.17083-1-david@redhat.com> References: <20200507140139.17083-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Let's add a parent resource, named after the virtio device (inspired by drivers/dax/kmem.c). This allows user space to identify which memory belongs to which virtio-mem device. With this change and two virtio-mem devices: :/# cat /proc/iomem 00000000-00000fff : Reserved 00001000-0009fbff : System RAM [...] 140000000-333ffffff : virtio0 140000000-147ffffff : System RAM 148000000-14fffffff : System RAM 150000000-157ffffff : System RAM [...] 334000000-3033ffffff : virtio1 338000000-33fffffff : System RAM 340000000-347ffffff : System RAM 348000000-34fffffff : System RAM [...] Cc: "Michael S. Tsirkin" Cc: Pankaj Gupta Signed-off-by: David Hildenbrand --- drivers/virtio/virtio_mem.c | 52 ++++++++++++++++++++++++++++++++++++- 1 file changed, 51 insertions(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c index eb4c16d634e0..80cdb9e6b3c4 100644 --- a/drivers/virtio/virtio_mem.c +++ b/drivers/virtio/virtio_mem.c @@ -99,6 +99,9 @@ struct virtio_mem { /* Id of the next memory bock to prepare when needed. */ unsigned long next_mb_id; =20 + /* The parent resource for all memory added via this device. */ + struct resource *parent_resource; + /* Summary of all memory block states. */ unsigned long nb_mb_state[VIRTIO_MEM_MB_STATE_COUNT]; #define VIRTIO_MEM_NB_OFFLINE_THRESHOLD 10 @@ -1741,6 +1744,44 @@ static int virtio_mem_init(struct virtio_mem *vm) return 0; } =20 +static int virtio_mem_create_resource(struct virtio_mem *vm) +{ + /* + * When force-unloading the driver and removing the device, we + * could have a garbage pointer. Duplicate the string. + */ + const char *name =3D kstrdup(dev_name(&vm->vdev->dev), GFP_KERNEL); + + if (!name) + return -ENOMEM; + + vm->parent_resource =3D __request_mem_region(vm->addr, vm->region_size, + name, IORESOURCE_SYSTEM_RAM); + if (!vm->parent_resource) { + kfree(name); + dev_warn(&vm->vdev->dev, "could not reserve device region\n"); + return -EBUSY; + } + + /* The memory is not actually busy - make add_memory() work. */ + vm->parent_resource->flags &=3D ~IORESOURCE_BUSY; + return 0; +} + +static void virtio_mem_delete_resource(struct virtio_mem *vm) +{ + const char *name; + + if (!vm->parent_resource) + return; + + name =3D vm->parent_resource->name; + release_resource(vm->parent_resource); + kfree(vm->parent_resource); + kfree(name); + vm->parent_resource =3D NULL; +} + static int virtio_mem_probe(struct virtio_device *vdev) { struct virtio_mem *vm; @@ -1770,11 +1811,16 @@ static int virtio_mem_probe(struct virtio_device = *vdev) if (rc) goto out_del_vq; =20 + /* create the parent resource for all memory */ + rc =3D virtio_mem_create_resource(vm); + if (rc) + goto out_del_vq; + /* register callbacks */ vm->memory_notifier.notifier_call =3D virtio_mem_memory_notifier_cb; rc =3D register_memory_notifier(&vm->memory_notifier); if (rc) - goto out_del_vq; + goto out_del_resource; rc =3D register_virtio_mem_device(vm); if (rc) goto out_unreg_mem; @@ -1788,6 +1834,8 @@ static int virtio_mem_probe(struct virtio_device *v= dev) return 0; out_unreg_mem: unregister_memory_notifier(&vm->memory_notifier); +out_del_resource: + virtio_mem_delete_resource(vm); out_del_vq: vdev->config->del_vqs(vdev); out_free_vm: @@ -1848,6 +1896,8 @@ static void virtio_mem_remove(struct virtio_device = *vdev) vm->nb_mb_state[VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL] || vm->nb_mb_state[VIRTIO_MEM_MB_STATE_ONLINE_MOVABLE]) dev_warn(&vdev->dev, "device still has system memory added\n"); + else + virtio_mem_delete_resource(vm); =20 /* remove all tracking data - no locking needed */ vfree(vm->mb_state); --=20 2.25.3