From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH v3 06/11] virtio: blk: Add freeze, restore handlers to support S4 Date: Thu, 17 Nov 2011 14:28:26 +0200 Message-ID: <20111117122825.GC19682@redhat.com> References: <81e98fc00370152ded2eef20f0953f19fad6f0f5.1321530505.git.amit.shah@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <81e98fc00370152ded2eef20f0953f19fad6f0f5.1321530505.git.amit.shah@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Amit Shah Cc: linux-kernel@vger.kernel.org, levinsasha928@gmail.com, Virtualization List List-Id: virtualization@lists.linuxfoundation.org On Thu, Nov 17, 2011 at 05:27:37PM +0530, Amit Shah wrote: > Delete the vq and flush any pending requests from the block queue on the > freeze callback to prepare for hibernation. > > Re-create the vq in the restore callback to resume normal function. > > Signed-off-by: Amit Shah > --- > drivers/block/virtio_blk.c | 36 ++++++++++++++++++++++++++++++++++++ > 1 files changed, 36 insertions(+), 0 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index 467f218..f73fb2d 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -568,6 +568,38 @@ static void __devexit virtblk_remove(struct virtio_device *vdev) > ida_simple_remove(&vd_index_ida, index); > } > > +#ifdef CONFIG_PM > +static int virtblk_freeze(struct virtio_device *vdev) > +{ > + struct virtio_blk *vblk = vdev->priv; > + > + flush_work(&vblk->config_work); What if a new config_work is scheduled after this point? The right thing to do seems to be to flush after disabling interrupts. > + spin_lock_irq(vblk->disk->queue->queue_lock); > + blk_stop_queue(vblk->disk->queue); > + spin_unlock_irq(vblk->disk->queue->queue_lock); > + blk_sync_queue(vblk->disk->queue); > + > + /* Stop all the virtqueues. */ > + vdev->config->reset(vdev); > + vdev->config->del_vqs(vdev); I think del_vqs should be followed by reset: del_vqs assumes the device in a state find put it in. > + return 0; > +} > + > +static int virtblk_restore(struct virtio_device *vdev) > +{ > + struct virtio_blk *vblk = vdev->priv; > + int ret; > + > + ret = init_vq(vdev->priv); > + if (!ret) { > + spin_lock_irq(vblk->disk->queue->queue_lock); > + blk_start_queue(vblk->disk->queue); > + spin_unlock_irq(vblk->disk->queue->queue_lock); > + } > + return ret; > +} > +#endif > + > static const struct virtio_device_id id_table[] = { > { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, > { 0 }, > @@ -593,6 +625,10 @@ static struct virtio_driver __refdata virtio_blk = { > .probe = virtblk_probe, > .remove = __devexit_p(virtblk_remove), > .config_changed = virtblk_config_changed, > +#ifdef CONFIG_PM > + .freeze = virtblk_freeze, > + .restore = virtblk_restore, > +#endif > }; > > static int __init init(void) > -- > 1.7.7.1