From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id E35836B000D for ; Fri, 6 Apr 2018 08:36:21 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id i137so596017pfe.0 for ; Fri, 06 Apr 2018 05:36:21 -0700 (PDT) Received: from mga14.intel.com (mga14.intel.com. [192.55.52.115]) by mx.google.com with ESMTPS id y1-v6si9100342pli.586.2018.04.06.05.36.20 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Apr 2018 05:36:20 -0700 (PDT) From: Wei Wang Subject: [PATCH v31 4/4] virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON Date: Fri, 6 Apr 2018 20:17:25 +0800 Message-Id: <1523017045-18315-5-git-send-email-wei.w.wang@intel.com> In-Reply-To: <1523017045-18315-1-git-send-email-wei.w.wang@intel.com> References: <1523017045-18315-1-git-send-email-wei.w.wang@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: virtio-dev@lists.oasis-open.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mhocko@kernel.org, akpm@linux-foundation.org Cc: pbonzini@redhat.com, wei.w.wang@intel.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu0@gmail.com, nilal@redhat.com, riel@redhat.com, huangzhichao@huawei.com The VIRTIO_BALLOON_F_PAGE_POISON feature bit is used to indicate if the guest is using page poisoning. Guest writes to the poison_val config field to tell host about the page poisoning value in use. Signed-off-by: Wei Wang Suggested-by: Michael S. Tsirkin Cc: Michael S. Tsirkin Cc: Michal Hocko Cc: Andrew Morton --- drivers/virtio/virtio_balloon.c | 10 ++++++++++ include/uapi/linux/virtio_balloon.h | 3 +++ 2 files changed, 13 insertions(+) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index aef73ee..47b02d5 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -714,6 +714,7 @@ static struct file_system_type balloon_fs = { static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; + __u32 poison_val; int err; if (!vdev->config->get) { @@ -759,6 +760,11 @@ static int virtballoon_probe(struct virtio_device *vdev) vb->stop_cmd_id = cpu_to_virtio32(vb->vdev, VIRTIO_BALLOON_FREE_PAGE_REPORT_STOP_ID); INIT_WORK(&vb->report_free_page_work, report_free_page_func); + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { + memset(&poison_val, PAGE_POISON, sizeof(poison_val)); + virtio_cwrite(vb->vdev, struct virtio_balloon_config, + poison_val, &poison_val); + } } vb->nb.notifier_call = virtballoon_oom_notify; @@ -877,6 +883,9 @@ static int virtballoon_restore(struct virtio_device *vdev) static int virtballoon_validate(struct virtio_device *vdev) { + if (!page_poisoning_enabled()) + __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_POISON); + __virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM); return 0; } @@ -886,6 +895,7 @@ static unsigned int features[] = { VIRTIO_BALLOON_F_STATS_VQ, VIRTIO_BALLOON_F_DEFLATE_ON_OOM, VIRTIO_BALLOON_F_FREE_PAGE_HINT, + VIRTIO_BALLOON_F_PAGE_POISON, }; static struct virtio_driver virtio_balloon_driver = { diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h index b2d86c2..8b93581 100644 --- a/include/uapi/linux/virtio_balloon.h +++ b/include/uapi/linux/virtio_balloon.h @@ -35,6 +35,7 @@ #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */ #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ #define VIRTIO_BALLOON_F_FREE_PAGE_HINT 3 /* VQ to report free pages */ +#define VIRTIO_BALLOON_F_PAGE_POISON 4 /* Guest is using page poisoning */ /* Size of a PFN in the balloon interface. */ #define VIRTIO_BALLOON_PFN_SHIFT 12 @@ -47,6 +48,8 @@ struct virtio_balloon_config { __u32 actual; /* Free page report command id, readonly by guest */ __u32 free_page_report_cmd_id; + /* Stores PAGE_POISON if page poisoning is in use */ + __u32 poison_val; }; #define VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */ -- 2.7.4