From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f69.google.com (mail-pl0-f69.google.com [209.85.160.69]) by kanga.kvack.org (Postfix) with ESMTP id A253D6B026D for ; Fri, 20 Jul 2018 05:00:44 -0400 (EDT) Received: by mail-pl0-f69.google.com with SMTP id w1-v6so6823441ply.12 for ; Fri, 20 Jul 2018 02:00:44 -0700 (PDT) Received: from mga04.intel.com (mga04.intel.com. [192.55.52.120]) by mx.google.com with ESMTPS id 196-v6si1455917pgg.588.2018.07.20.02.00.43 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 20 Jul 2018 02:00:43 -0700 (PDT) From: Wei Wang Subject: [PATCH v36 5/5] virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON Date: Fri, 20 Jul 2018 16:33:05 +0800 Message-Id: <1532075585-39067-6-git-send-email-wei.w.wang@intel.com> In-Reply-To: <1532075585-39067-1-git-send-email-wei.w.wang@intel.com> References: <1532075585-39067-1-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, torvalds@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, peterx@redhat.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 that is in use. Suggested-by: Michael S. Tsirkin Signed-off-by: Wei Wang 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 82cd497..6340cc1 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -814,6 +814,7 @@ static int virtio_balloon_register_shrinker(struct virtio_balloon *vb) static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; + __u32 poison_val; int err; if (!vdev->config->get) { @@ -883,6 +884,11 @@ static int virtballoon_probe(struct virtio_device *vdev) VIRTIO_BALLOON_CMD_ID_STOP); spin_lock_init(&vb->free_page_list_lock); INIT_LIST_HEAD(&vb->free_page_list); + 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); + } } err = virtio_balloon_register_shrinker(vb); @@ -979,6 +985,9 @@ 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; } @@ -988,6 +997,7 @@ 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 18ee430..80a7b7e 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