linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Wei Wang <wei.w.wang@intel.com>
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
Subject: [PATCH v28 4/4] virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON
Date: Thu,  8 Feb 2018 17:50:20 +0800	[thread overview]
Message-ID: <1518083420-11108-5-git-send-email-wei.w.wang@intel.com> (raw)
In-Reply-To: <1518083420-11108-1-git-send-email-wei.w.wang@intel.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 <wei.w.wang@intel.com>
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
 drivers/virtio/virtio_balloon.c     | 13 +++++++++++++
 include/uapi/linux/virtio_balloon.h |  3 +++
 2 files changed, 16 insertions(+)

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 39ecce3..9fa7fcf 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -685,6 +685,7 @@ 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) {
@@ -728,6 +729,12 @@ static int virtballoon_probe(struct virtio_device *vdev)
 			goto out_del_vqs;
 		}
 		INIT_WORK(&vb->report_free_page_work, report_free_page_func);
+		if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) {
+			page_poison_val_get((u8 *)&poison_val);
+			memset(&poison_val, poison_val, sizeof(poison_val));
+			virtio_cwrite(vb->vdev, struct virtio_balloon_config,
+				      poison_val, &poison_val);
+		}
 	}
 
 	vb->nb.notifier_call = virtballoon_oom_notify;
@@ -846,6 +853,11 @@ static int virtballoon_restore(struct virtio_device *vdev)
 
 static int virtballoon_validate(struct virtio_device *vdev)
 {
+	uint8_t unused;
+
+	if (!page_poison_val_get(&unused))
+		__virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_POISON);
+
 	__virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM);
 	return 0;
 }
@@ -855,6 +867,7 @@ 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 0c654db..3f97067 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

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  parent reply	other threads:[~2018-02-08 10:09 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-08  9:50 [PATCH v28 0/4] Virtio-balloon: support free page reporting Wei Wang
2018-02-08  9:50 ` [PATCH v28 1/4] mm: support reporting free page blocks Wei Wang
2018-02-08  9:50 ` [PATCH v28 2/4] virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT Wei Wang
2018-02-08  9:50 ` [PATCH v28 3/4] mm/page_poison: add a function to expose page poison val to kernel modules Wei Wang
2018-02-08 19:29   ` Michael S. Tsirkin
2018-02-08  9:50 ` Wei Wang [this message]
2018-02-08 19:25   ` [PATCH v28 4/4] virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON Michael S. Tsirkin
2018-02-08 19:31   ` Michael S. Tsirkin
2018-02-08 19:55 ` [PATCH v28 0/4] Virtio-balloon: support free page reporting Michael S. Tsirkin
2018-02-09  3:11   ` Wei Wang
2018-02-09  3:14     ` Michael S. Tsirkin
2018-02-26  4:01       ` Wei Wang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1518083420-11108-5-git-send-email-wei.w.wang@intel.com \
    --to=wei.w.wang@intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=huangzhichao@huawei.com \
    --cc=kvm@vger.kernel.org \
    --cc=liliang.opensource@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@kernel.org \
    --cc=mst@redhat.com \
    --cc=nilal@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=quan.xu0@gmail.com \
    --cc=riel@redhat.com \
    --cc=virtio-dev@lists.oasis-open.org \
    --cc=virtualization@lists.linux-foundation.org \
    --cc=yang.zhang.wz@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).