-/* Virtio balloon implementation, inspired by Dor Loar and Marcelo
+/*
+ * Virtio balloon implementation, inspired by Dor Laor and Marcelo
* Tosatti's implementations.
*
* Copyright 2008 Rusty Russell IBM Corporation
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
-//#define DEBUG
+
#include <linux/virtio.h>
#include <linux/virtio_balloon.h>
#include <linux/swap.h>
#include <linux/freezer.h>
#include <linux/delay.h>
#include <linux/slab.h>
+#include <linux/module.h>
struct virtio_balloon
{
/* Waiting for host to ack the pages we released. */
struct completion acked;
- /* Do we have to tell Host *before* we reuse pages? */
- bool tell_host_first;
-
/* The pages we've told the Host we're not using. */
unsigned int num_pages;
struct list_head pages;
struct virtio_balloon *vb;
unsigned int len;
- vb = vq->vq_ops->get_buf(vq, &len);
+ vb = virtqueue_get_buf(vq, &len);
if (vb)
complete(&vb->acked);
}
init_completion(&vb->acked);
/* We should always be able to add one buffer to an empty queue. */
- if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) < 0)
+ if (virtqueue_add_buf(vq, &sg, 1, 0, vb, GFP_KERNEL) < 0)
BUG();
- vq->vq_ops->kick(vq);
+ virtqueue_kick(vq);
/* When host has read buffer, this completes via balloon_ack */
wait_for_completion(&vb->acked);
vb->num_pages--;
}
- if (vb->tell_host_first) {
- tell_host(vb, vb->deflate_vq);
- release_pages_by_pfn(vb->pfns, vb->num_pfns);
- } else {
- release_pages_by_pfn(vb->pfns, vb->num_pfns);
- tell_host(vb, vb->deflate_vq);
- }
+ /*
+ * Note that if
+ * virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
+ * is true, we *have* to do it in this order
+ */
+ tell_host(vb, vb->deflate_vq);
+ release_pages_by_pfn(vb->pfns, vb->num_pfns);
}
static inline void update_stat(struct virtio_balloon *vb, int idx,
struct virtio_balloon *vb;
unsigned int len;
- vb = vq->vq_ops->get_buf(vq, &len);
+ vb = virtqueue_get_buf(vq, &len);
if (!vb)
return;
vb->need_stats_update = 1;
vq = vb->stats_vq;
sg_init_one(&sg, vb->stats, sizeof(vb->stats));
- if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) < 0)
+ if (virtqueue_add_buf(vq, &sg, 1, 0, vb, GFP_KERNEL) < 0)
BUG();
- vq->vq_ops->kick(vq);
+ virtqueue_kick(vq);
}
static void virtballoon_changed(struct virtio_device *vdev)
return 0;
}
-static int virtballoon_probe(struct virtio_device *vdev)
+static int init_vqs(struct virtio_balloon *vb)
{
- struct virtio_balloon *vb;
struct virtqueue *vqs[3];
vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request };
const char *names[] = { "inflate", "deflate", "stats" };
int err, nvqs;
- vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
- if (!vb) {
- err = -ENOMEM;
- goto out;
- }
-
- INIT_LIST_HEAD(&vb->pages);
- vb->num_pages = 0;
- init_waitqueue_head(&vb->config_change);
- vb->vdev = vdev;
- vb->need_stats_update = 0;
-
- /* We expect two virtqueues: inflate and deflate,
- * and optionally stat. */
+ /*
+ * We expect two virtqueues: inflate and deflate, and
+ * optionally stat.
+ */
nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2;
- err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
+ err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks, names);
if (err)
- goto out_free_vb;
+ return err;
vb->inflate_vq = vqs[0];
vb->deflate_vq = vqs[1];
* use it to signal us later.
*/
sg_init_one(&sg, vb->stats, sizeof vb->stats);
- if (vb->stats_vq->vq_ops->add_buf(vb->stats_vq,
- &sg, 1, 0, vb) < 0)
+ if (virtqueue_add_buf(vb->stats_vq, &sg, 1, 0, vb, GFP_KERNEL)
+ < 0)
BUG();
- vb->stats_vq->vq_ops->kick(vb->stats_vq);
+ virtqueue_kick(vb->stats_vq);
+ }
+ return 0;
+}
+
+static int virtballoon_probe(struct virtio_device *vdev)
+{
+ struct virtio_balloon *vb;
+ int err;
+
+ vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
+ if (!vb) {
+ err = -ENOMEM;
+ goto out;
}
+ INIT_LIST_HEAD(&vb->pages);
+ vb->num_pages = 0;
+ init_waitqueue_head(&vb->config_change);
+ vb->vdev = vdev;
+ vb->need_stats_update = 0;
+
+ err = init_vqs(vb);
+ if (err)
+ goto out_free_vb;
+
vb->thread = kthread_run(balloon, vb, "vballoon");
if (IS_ERR(vb->thread)) {
err = PTR_ERR(vb->thread);
goto out_del_vqs;
}
- vb->tell_host_first
- = virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
-
return 0;
out_del_vqs:
kfree(vb);
}
+#ifdef CONFIG_PM
+static int virtballoon_freeze(struct virtio_device *vdev)
+{
+ struct virtio_balloon *vb = vdev->priv;
+
+ /*
+ * The kthread is already frozen by the PM core before this
+ * function is called.
+ */
+
+ while (vb->num_pages)
+ leak_balloon(vb, vb->num_pages);
+ update_balloon_size(vb);
+
+ /* Ensure we don't get any more requests from the host */
+ vdev->config->reset(vdev);
+ vdev->config->del_vqs(vdev);
+ return 0;
+}
+
+static int restore_common(struct virtio_device *vdev)
+{
+ struct virtio_balloon *vb = vdev->priv;
+ int ret;
+
+ ret = init_vqs(vdev->priv);
+ if (ret)
+ return ret;
+
+ fill_balloon(vb, towards_target(vb));
+ update_balloon_size(vb);
+ return 0;
+}
+
+static int virtballoon_restore(struct virtio_device *vdev)
+{
+ return restore_common(vdev);
+}
+#endif
+
static unsigned int features[] = {
VIRTIO_BALLOON_F_MUST_TELL_HOST,
VIRTIO_BALLOON_F_STATS_VQ,
.probe = virtballoon_probe,
.remove = __devexit_p(virtballoon_remove),
.config_changed = virtballoon_changed,
+#ifdef CONFIG_PM
+ .freeze = virtballoon_freeze,
+ .restore = virtballoon_restore,
+#endif
};
static int __init init(void)