virtio: explicit enable_cb/disable_cb rather than callback return. It seems that virtio_net wants to disable callbacks (interrupts) before calling netif_rx_schedule(), so we can't use the return value to do so. Rename "restart" to "cb_enable" and introduce "cb_disable" hook: callback now returns void, rather than a boolean. Signed-off-by: Rusty Russell --- drivers/block/virtio_blk.c | 3 +-- drivers/lguest/lguest_device.c | 2 +- drivers/net/virtio_net.c | 15 ++++++++------- drivers/virtio/virtio_pci.c | 2 +- drivers/virtio/virtio_ring.c | 21 ++++++++++++++++----- include/linux/virtio.h | 11 ++++++----- include/linux/virtio_config.h | 2 +- include/linux/virtio_ring.h | 2 +- net/9p/trans_virtio.c | 4 +--- 9 files changed, 36 insertions(+), 26 deletions(-) diff -r a53e9de3ae53 drivers/block/virtio_blk.c --- a/drivers/block/virtio_blk.c Wed Jan 09 22:57:38 2008 +1100 +++ b/drivers/block/virtio_blk.c Fri Jan 11 14:04:40 2008 +1100 @@ -36,7 +36,7 @@ struct virtblk_req struct virtio_blk_inhdr in_hdr; }; -static bool blk_done(struct virtqueue *vq) +static void blk_done(struct virtqueue *vq) { struct virtio_blk *vblk = vq->vdev->priv; struct virtblk_req *vbr; @@ -65,7 +65,6 @@ static bool blk_done(struct virtqueue *v /* In case queue is stopped waiting for more buffers. */ blk_start_queue(vblk->disk->queue); spin_unlock_irqrestore(&vblk->lock, flags); - return true; } static bool do_req(struct request_queue *q, struct virtio_blk *vblk, diff -r a53e9de3ae53 drivers/lguest/lguest_device.c --- a/drivers/lguest/lguest_device.c Wed Jan 09 22:57:38 2008 +1100 +++ b/drivers/lguest/lguest_device.c Fri Jan 11 14:04:41 2008 +1100 @@ -193,7 +193,7 @@ static void lg_notify(struct virtqueue * * So we provide devices with a "find virtqueue and set it up" function. */ static struct virtqueue *lg_find_vq(struct virtio_device *vdev, unsigned index, - bool (*callback)(struct virtqueue *vq)) + void (*callback)(struct virtqueue *vq)) { struct lguest_device *ldev = to_lgdev(vdev); struct lguest_vq_info *lvq; diff -r a53e9de3ae53 drivers/net/virtio_net.c --- a/drivers/net/virtio_net.c Wed Jan 09 22:57:38 2008 +1100 +++ b/drivers/net/virtio_net.c Fri Jan 11 14:04:41 2008 +1100 @@ -52,13 +52,12 @@ static inline void vnet_hdr_to_sg(struct sg_init_one(sg, skb_vnet_hdr(skb), sizeof(struct virtio_net_hdr)); } -static bool skb_xmit_done(struct virtqueue *rvq) +static void skb_xmit_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; /* In case we were waiting for output buffers. */ netif_wake_queue(vi->dev); - return true; } static void receive_skb(struct net_device *dev, struct sk_buff *skb, @@ -170,12 +169,14 @@ static void try_fill_recv(struct virtnet vi->rvq->vq_ops->kick(vi->rvq); } -static bool skb_recv_done(struct virtqueue *rvq) +static void skb_recv_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; - netif_rx_schedule(vi->dev, &vi->napi); - /* Suppress further interrupts. */ - return false; + /* Schedule NAPI, Suppress further interrupts if successful. */ + if (netif_rx_schedule_prep(vi->dev, &vi->napi)) { + rvq->vq_ops->disable_cb(rvq); + __netif_rx_schedule(vi->dev, &vi->napi); + } } static int virtnet_poll(struct napi_struct *napi, int budget) @@ -201,7 +203,7 @@ again: /* Out of packets? */ if (received < budget) { netif_rx_complete(vi->dev, napi); - if (unlikely(!vi->rvq->vq_ops->restart(vi->rvq)) + if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) && netif_rx_reschedule(vi->dev, napi)) goto again; } diff -r a53e9de3ae53 drivers/virtio/virtio_pci.c --- a/drivers/virtio/virtio_pci.c Wed Jan 09 22:57:38 2008 +1100 +++ b/drivers/virtio/virtio_pci.c Fri Jan 11 14:04:41 2008 +1100 @@ -190,7 +190,7 @@ static irqreturn_t vp_interrupt(int irq, /* the config->find_vq() implementation */ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index, - bool (*callback)(struct virtqueue *vq)) + void (*callback)(struct virtqueue *vq)) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct virtio_pci_vq_info *info; diff -r a53e9de3ae53 drivers/virtio/virtio_ring.c --- a/drivers/virtio/virtio_ring.c Wed Jan 09 22:57:38 2008 +1100 +++ b/drivers/virtio/virtio_ring.c Fri Jan 11 14:04:41 2008 +1100 @@ -222,7 +222,17 @@ static void *vring_get_buf(struct virtqu return ret; } -static bool vring_restart(struct virtqueue *_vq) +static void vring_disable_cb(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + START_USE(vq); + BUG_ON(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT); + vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; + END_USE(vq); +} + +static bool vring_enable_cb(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); @@ -256,8 +266,8 @@ irqreturn_t vring_interrupt(int irq, voi return IRQ_HANDLED; pr_debug("virtqueue callback for %p (%p)\n", vq, vq->vq.callback); - if (vq->vq.callback && !vq->vq.callback(&vq->vq)) - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; + if (vq->vq.callback) + vq->vq.callback(&vq->vq); return IRQ_HANDLED; } @@ -268,7 +278,8 @@ static struct virtqueue_ops vring_vq_ops .add_buf = vring_add_buf, .get_buf = vring_get_buf, .kick = vring_kick, - .restart = vring_restart, + .disable_cb = vring_disable_cb, + .enable_cb = vring_enable_cb, .shutdown = vring_shutdown, }; @@ -276,7 +287,7 @@ struct virtqueue *vring_new_virtqueue(un struct virtio_device *vdev, void *pages, void (*notify)(struct virtqueue *), - bool (*callback)(struct virtqueue *)) + void (*callback)(struct virtqueue *)) { struct vring_virtqueue *vq; unsigned int i; diff -r a53e9de3ae53 include/linux/virtio.h --- a/include/linux/virtio.h Wed Jan 09 22:57:38 2008 +1100 +++ b/include/linux/virtio.h Fri Jan 11 14:04:41 2008 +1100 @@ -11,15 +11,13 @@ /** * virtqueue - a queue to register buffers for sending or receiving. * @callback: the function to call when buffers are consumed (can be NULL). - * If this returns false, callbacks are suppressed until vq_ops->restart - * is called. * @vdev: the virtio device this queue was created for. * @vq_ops: the operations for this virtqueue (see below). * @priv: a pointer for the virtqueue implementation to use. */ struct virtqueue { - bool (*callback)(struct virtqueue *vq); + void (*callback)(struct virtqueue *vq); struct virtio_device *vdev; struct virtqueue_ops *vq_ops; void *priv; @@ -41,7 +39,9 @@ struct virtqueue * vq: the struct virtqueue we're talking about. * len: the length written into the buffer * Returns NULL or the "data" token handed to add_buf. - * @restart: restart callbacks after callback returned false. + * @disable_cb: disable callbacks + * vq: the struct virtqueue we're talking about. + * @enable_cb: restart callbacks after disable_cb. * vq: the struct virtqueue we're talking about. * This returns "false" (and doesn't re-enable) if there are pending * buffers in the queue, to avoid a race. @@ -65,7 +65,8 @@ struct virtqueue_ops { void *(*get_buf)(struct virtqueue *vq, unsigned int *len); - bool (*restart)(struct virtqueue *vq); + void (*disable_cb)(struct virtqueue *vq); + bool (*enable_cb)(struct virtqueue *vq); void (*shutdown)(struct virtqueue *vq); }; diff -r a53e9de3ae53 include/linux/virtio_config.h --- a/include/linux/virtio_config.h Wed Jan 09 22:57:38 2008 +1100 +++ b/include/linux/virtio_config.h Fri Jan 11 14:04:41 2008 +1100 @@ -61,7 +61,7 @@ struct virtio_config_ops void (*set_status)(struct virtio_device *vdev, u8 status); struct virtqueue *(*find_vq)(struct virtio_device *vdev, unsigned index, - bool (*callback)(struct virtqueue *)); + void (*callback)(struct virtqueue *)); void (*del_vq)(struct virtqueue *vq); }; diff -r a53e9de3ae53 include/linux/virtio_ring.h --- a/include/linux/virtio_ring.h Wed Jan 09 22:57:38 2008 +1100 +++ b/include/linux/virtio_ring.h Fri Jan 11 14:04:41 2008 +1100 @@ -118,7 +118,7 @@ struct virtqueue *vring_new_virtqueue(un struct virtio_device *vdev, void *pages, void (*notify)(struct virtqueue *vq), - bool (*callback)(struct virtqueue *vq)); + void (*callback)(struct virtqueue *vq)); void vring_del_virtqueue(struct virtqueue *vq); irqreturn_t vring_interrupt(int irq, void *_vq); diff -r a53e9de3ae53 net/9p/trans_virtio.c --- a/net/9p/trans_virtio.c Wed Jan 09 22:57:38 2008 +1100 +++ b/net/9p/trans_virtio.c Fri Jan 11 14:04:41 2008 +1100 @@ -199,14 +199,12 @@ static void p9_virtio_close(struct p9_tr kfree(trans); } -static bool p9_virtio_intr(struct virtqueue *q) +static void p9_virtio_intr(struct virtqueue *q) { struct virtio_chan *chan = q->vdev->priv; P9_DPRINTK(P9_DEBUG_TRANS, "9p poll_wakeup: %p\n", &chan->wq); wake_up_interruptible(&chan->wq); - - return true; } static int p9_virtio_probe(struct virtio_device *dev)