* [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
[not found] <cover.1242080138.git.mst@redhat.com>
@ 2009-05-11 22:19 ` Michael S. Tsirkin
2009-05-12 8:55 ` Christian Borntraeger
` (3 more replies)
2009-05-11 22:19 ` Michael S. Tsirkin
` (4 subsequent siblings)
5 siblings, 4 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-11 22:19 UTC (permalink / raw)
To: Christian Borntraeger, Rusty Russell, virtualization,
Anthony Liguori, kvm
This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
and updates all drivers. This is needed for MSI support, because MSI
needs to know the total number of vectors upfront.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/block/virtio_blk.c | 11 +++---
drivers/char/hw_random/virtio-rng.c | 11 +++---
drivers/char/virtio_console.c | 27 ++++++--------
drivers/lguest/lguest_device.c | 49 +++++++++++++++++++++++++-
drivers/net/virtio_net.c | 48 +++++++++++---------------
drivers/s390/kvm/kvm_virtio.c | 64 +++++++++++++++++++++++++++++++++-
drivers/virtio/virtio_balloon.c | 29 +++++++---------
drivers/virtio/virtio_pci.c | 43 +++++++++++++++++++----
include/linux/virtio_config.h | 29 +++++++++++-----
net/9p/trans_virtio.c | 7 ++--
10 files changed, 225 insertions(+), 93 deletions(-)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 5d34764..7b7435d 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -197,6 +197,7 @@ static int virtblk_probe(struct virtio_device *vdev)
u64 cap;
u32 v;
u32 blk_size, sg_elems;
+ virtqueue_callback *callback[] = { blk_done };
if (index_to_minor(index) >= 1 << MINORBITS)
return -ENOSPC;
@@ -224,11 +225,9 @@ static int virtblk_probe(struct virtio_device *vdev)
sg_init_table(vblk->sg, vblk->sg_elems);
/* We expect one virtqueue, for output. */
- vblk->vq = vdev->config->find_vq(vdev, 0, blk_done);
- if (IS_ERR(vblk->vq)) {
- err = PTR_ERR(vblk->vq);
+ err = vdev->config->find_vqs(vdev, 1, &vblk->vq, callback);
+ if (err)
goto out_free_vblk;
- }
vblk->pool = mempool_create_kmalloc_pool(1,sizeof(struct virtblk_req));
if (!vblk->pool) {
@@ -323,7 +322,7 @@ out_put_disk:
out_mempool:
mempool_destroy(vblk->pool);
out_free_vq:
- vdev->config->del_vq(vblk->vq);
+ vdev->config->del_vqs(vdev);
out_free_vblk:
kfree(vblk);
out:
@@ -344,7 +343,7 @@ static void virtblk_remove(struct virtio_device *vdev)
blk_cleanup_queue(vblk->disk->queue);
put_disk(vblk->disk);
mempool_destroy(vblk->pool);
- vdev->config->del_vq(vblk->vq);
+ vdev->config->del_vqs(vdev);
kfree(vblk);
}
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index 86e83f8..18eabe4 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -91,16 +91,17 @@ static struct hwrng virtio_hwrng = {
static int virtrng_probe(struct virtio_device *vdev)
{
+ virtqueue_callback *callback[] = { random_recv_done };
int err;
/* We expect a single virtqueue. */
- vq = vdev->config->find_vq(vdev, 0, random_recv_done);
- if (IS_ERR(vq))
- return PTR_ERR(vq);
+ err = vdev->config->find_vqs(vdev, 1, &vq, callback);
+ if (err)
+ return err;
err = hwrng_register(&virtio_hwrng);
if (err) {
- vdev->config->del_vq(vq);
+ vdev->config->del_vqs(vdev);
return err;
}
@@ -112,7 +113,7 @@ static void virtrng_remove(struct virtio_device *vdev)
{
vdev->config->reset(vdev);
hwrng_unregister(&virtio_hwrng);
- vdev->config->del_vq(vq);
+ vdev->config->del_vqs(vdev);
}
static struct virtio_device_id id_table[] = {
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index ff6f5a4..1fd5376 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -188,6 +188,8 @@ static void hvc_handle_input(struct virtqueue *vq)
* Finally we put our input buffer in the input queue, ready to receive. */
static int __devinit virtcons_probe(struct virtio_device *dev)
{
+ struct virtqueue *vqs[2];
+ virtqueue_callback *callbacks[2];
int err;
vdev = dev;
@@ -199,20 +201,17 @@ static int __devinit virtcons_probe(struct virtio_device *dev)
goto fail;
}
- /* Find the input queue. */
+ /* Find the queues. */
/* FIXME: This is why we want to wean off hvc: we do nothing
* when input comes in. */
- in_vq = vdev->config->find_vq(vdev, 0, hvc_handle_input);
- if (IS_ERR(in_vq)) {
- err = PTR_ERR(in_vq);
+ callbacks[0] = hvc_handle_input;
+ callbacks[1] = NULL;
+ err = vdev->config->find_vqs(vdev, 2, vqs, callbacks);
+ if (err)
goto free;
- }
- out_vq = vdev->config->find_vq(vdev, 1, NULL);
- if (IS_ERR(out_vq)) {
- err = PTR_ERR(out_vq);
- goto free_in_vq;
- }
+ in_vq = vqs[0];
+ out_vq = vqs[1];
/* Start using the new console output. */
virtio_cons.get_chars = get_chars;
@@ -233,17 +232,15 @@ static int __devinit virtcons_probe(struct virtio_device *dev)
hvc = hvc_alloc(0, 0, &virtio_cons, PAGE_SIZE);
if (IS_ERR(hvc)) {
err = PTR_ERR(hvc);
- goto free_out_vq;
+ goto free_vqs;
}
/* Register the input buffer the first time. */
add_inbuf();
return 0;
-free_out_vq:
- vdev->config->del_vq(out_vq);
-free_in_vq:
- vdev->config->del_vq(in_vq);
+free_vqs:
+ vdev->config->del_vqs(vdev);
free:
kfree(inbuf);
fail:
diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c
index df44d96..53699aa 100644
--- a/drivers/lguest/lguest_device.c
+++ b/drivers/lguest/lguest_device.c
@@ -37,6 +37,10 @@ static inline void lguest_unmap(void *addr)
struct lguest_device {
struct virtio_device vdev;
+ /* Array of virtqueues */
+ struct virtqueue **vqs;
+ int nvqs;
+
/* The entry in the lguest_devices page for this device. */
struct lguest_device_desc *desc;
};
@@ -312,6 +316,47 @@ static void lg_del_vq(struct virtqueue *vq)
kfree(lvq);
}
+static void lg_del_vqs(struct virtio_device *vdev)
+{
+ struct lguest_device *ldev = to_lgdev(vdev);
+ int i;
+ if (!ldev->vqs)
+ return;
+ for (i = 0; i < ldev->nvqs; ++i)
+ lg_del_vq(ldev->vqs[i]);
+ kfree(ldev->vqs);
+ ldev->vqs = NULL;
+ ldev->nvqs = 0;
+}
+
+static int lg_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[]
+ void (*callbacks)[](struct virtqueue *))
+{
+ struct lguest_device *ldev = to_lgdev(vdev);
+ int i;
+
+ /* We must have this many virtqueues. */
+ if (nvqs > ldev->desc->num_vq)
+ return ERR_PTR(-ENOENT);
+
+ ldev->vqs = kmalloc(GFP_KERNEL, nvqs * sizeof *ldev->vqs);
+ if (!ldev->vqs)
+ return -ENOMEM;
+
+ for (i = 0; i < nvqs; ++i) {
+ ldev->vqs[i] = vqs[i] = lg_find_vq(vdev, i, callbacks[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ ldev->nvqs = i;
+ }
+ return 0;
+
+error:
+ vp_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
/* The ops structure which hooks everything together. */
static struct virtio_config_ops lguest_config_ops = {
.get_features = lg_get_features,
@@ -321,8 +366,8 @@ static struct virtio_config_ops lguest_config_ops = {
.get_status = lg_get_status,
.set_status = lg_set_status,
.reset = lg_reset,
- .find_vq = lg_find_vq,
- .del_vq = lg_del_vq,
+ .find_vqs = lg_find_vqs,
+ .del_vqs = lg_del_vqs,
};
/* The root device for the lguest virtio devices. This makes them appear as
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 4d1d479..862a314 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -845,6 +845,9 @@ static int virtnet_probe(struct virtio_device *vdev)
int err;
struct net_device *dev;
struct virtnet_info *vi;
+ struct virtqueue *vqs[3];
+ virtqueue_callback *callbacks[3];
+ int nvqs;
/* Allocate ourselves a network device with room for our info */
dev = alloc_etherdev(sizeof(struct virtnet_info));
@@ -905,25 +908,23 @@ static int virtnet_probe(struct virtio_device *vdev)
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
vi->mergeable_rx_bufs = true;
- /* We expect two virtqueues, receive then send. */
- vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
- if (IS_ERR(vi->rvq)) {
- err = PTR_ERR(vi->rvq);
+ /* We expect two virtqueues, receive then send,
+ * and optionally control. */
+ callbacks[0] = skb_recv_done;
+ callbacks[1] = skb_xmit_done;
+ callbacks[2] = NULL;
+
+ nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
+
+ err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks);
+ if (err)
goto free;
- }
- vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
- if (IS_ERR(vi->svq)) {
- err = PTR_ERR(vi->svq);
- goto free_recv;
- }
+ vi->rvq = vqs[0];
+ vi->svq = vqs[1];
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
- vi->cvq = vdev->config->find_vq(vdev, 2, NULL);
- if (IS_ERR(vi->cvq)) {
- err = PTR_ERR(vi->svq);
- goto free_send;
- }
+ vi->cvq = vqs[2];
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
dev->features |= NETIF_F_HW_VLAN_FILTER;
@@ -941,7 +942,7 @@ static int virtnet_probe(struct virtio_device *vdev)
err = register_netdev(dev);
if (err) {
pr_debug("virtio_net: registering device failed\n");
- goto free_ctrl;
+ goto free_vqs;
}
/* Last of all, set up some receive buffers. */
@@ -962,13 +963,8 @@ static int virtnet_probe(struct virtio_device *vdev)
unregister:
unregister_netdev(dev);
-free_ctrl:
- if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
- vdev->config->del_vq(vi->cvq);
-free_send:
- vdev->config->del_vq(vi->svq);
-free_recv:
- vdev->config->del_vq(vi->rvq);
+free_vqs:
+ vdev->config->del_vqs(vdev);
free:
free_netdev(dev);
return err;
@@ -994,12 +990,10 @@ static void virtnet_remove(struct virtio_device *vdev)
BUG_ON(vi->num != 0);
- vdev->config->del_vq(vi->svq);
- vdev->config->del_vq(vi->rvq);
- if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
- vdev->config->del_vq(vi->cvq);
unregister_netdev(vi->dev);
+ vdev->config->del_vqs(vi->vdev);
+
while (vi->pages)
__free_pages(get_a_page(vi, GFP_KERNEL), 0);
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index cbc8566..6787426 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -34,6 +34,11 @@ static void *kvm_devices;
struct kvm_device {
struct virtio_device vdev;
+
+ /* Array of virtqueues */
+ struct virtqueue **vqs;
+ int nvqs;
+
struct kvm_device_desc *desc;
};
@@ -226,6 +231,61 @@ static void kvm_del_vq(struct virtqueue *vq)
KVM_S390_VIRTIO_RING_ALIGN));
}
+static void kvm_del_vqs(struct virtio_device *vdev)
+{
+ struct kvm_device *kdev = to_kvmdev(vdev);
+ int i;
+ if (!kdev->vqs)
+ return;
+ for (i = 0; i < ldev->nvqs; ++i)
+ kvm_del_vq(kdev->vqs[i]);
+ kfree(ldev->vqs);
+ ldev->vqs = NULL;
+ ldev->nvqs = 0;
+}
+
+static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[]
+ void (*callbacks)[](struct virtqueue *))
+{
+ struct kvm_device *kdev = to_kvmdev(vdev);
+ int i;
+
+ /* We must have this many virtqueues. */
+ if (nvqs > kdev->desc->num_vq)
+ return ERR_PTR(-ENOENT);
+
+ kdev->vqs = kmalloc(GFP_KERNEL, nvqs * sizeof *kdev->vqs);
+ if (!kdev->vqs)
+ return -ENOMEM;
+
+ for (i = 0; i < nvqs; ++i) {
+ kdev->vqs[i] = vqs[i] = kvm_find_vq(vdev, i, callbacks[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ kdev->nvqs = i;
+ }
+ return 0;
+
+error:
+ kvm_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
+static void kvm_del_vqs(struct virtio_device *vdev)
+{
+ struct lguest_device *ldev = to_lgdev(vdev);
+ int i;
+
+ if (!ldev->vqs)
+ return;
+ for (i = 0; i < ldev->nvqs; ++i)
+ lg_del_vq(ldev->vqs[i]);
+ kfree(ldev->vqs);
+ ldev->vqs = NULL;
+ ldev->nvqs = 0;
+}
+
/*
* The config ops structure as defined by virtio config
*/
@@ -237,8 +297,8 @@ static struct virtio_config_ops kvm_vq_configspace_ops = {
.get_status = kvm_get_status,
.set_status = kvm_set_status,
.reset = kvm_reset,
- .find_vq = kvm_find_vq,
- .del_vq = kvm_del_vq,
+ .find_vqs = kvm_find_vqs,
+ .del_vqs = kvm_del_vqs,
};
/*
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 9c76a06..ef7c481 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -204,6 +204,8 @@ static int balloon(void *_vballoon)
static int virtballoon_probe(struct virtio_device *vdev)
{
struct virtio_balloon *vb;
+ struct virtqueue *vqs[2];
+ virtqueue_callback *callbacks[2];
int err;
vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
@@ -218,22 +220,20 @@ static int virtballoon_probe(struct virtio_device *vdev)
vb->vdev = vdev;
/* We expect two virtqueues. */
- vb->inflate_vq = vdev->config->find_vq(vdev, 0, balloon_ack);
- if (IS_ERR(vb->inflate_vq)) {
- err = PTR_ERR(vb->inflate_vq);
+ callbacks[0] = balloon_ack;
+ callbacks[1] = balloon_ack;
+
+ err = vdev->config->find_vqs(vdev, 2, vqs, callbacks);
+ if (err)
goto out_free_vb;
- }
- vb->deflate_vq = vdev->config->find_vq(vdev, 1, balloon_ack);
- if (IS_ERR(vb->deflate_vq)) {
- err = PTR_ERR(vb->deflate_vq);
- goto out_del_inflate_vq;
- }
+ vb->inflate_vq = vqs[0];
+ vb->deflate_vq = vqs[1];
vb->thread = kthread_run(balloon, vb, "vballoon");
if (IS_ERR(vb->thread)) {
err = PTR_ERR(vb->thread);
- goto out_del_deflate_vq;
+ goto out_del_vqs;
}
vb->tell_host_first
@@ -241,10 +241,8 @@ static int virtballoon_probe(struct virtio_device *vdev)
return 0;
-out_del_deflate_vq:
- vdev->config->del_vq(vb->deflate_vq);
-out_del_inflate_vq:
- vdev->config->del_vq(vb->inflate_vq);
+out_del_vqs:
+ vdev->config->del_vqs(vdev);
out_free_vb:
kfree(vb);
out:
@@ -264,8 +262,7 @@ static void virtballoon_remove(struct virtio_device *vdev)
/* Now we reset the device so we can clean up the queues. */
vdev->config->reset(vdev);
- vdev->config->del_vq(vb->deflate_vq);
- vdev->config->del_vq(vb->inflate_vq);
+ vdev->config->del_vqs(vdev);
kfree(vb);
}
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 330aacb..d5e030f 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -275,11 +275,7 @@ static void vp_del_vq(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
struct virtio_pci_vq_info *info = vq->priv;
- unsigned long flags, size;
-
- spin_lock_irqsave(&vp_dev->lock, flags);
- list_del(&info->node);
- spin_unlock_irqrestore(&vp_dev->lock, flags);
+ unsigned long size;
vring_del_virtqueue(vq);
@@ -292,14 +288,47 @@ static void vp_del_vq(struct virtqueue *vq)
kfree(info);
}
+static void vp_del_vqs(struct virtio_device *vdev)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ struct virtio_pci_vq_info *info;
+ struct list_head virtqueues;
+ unsigned long flags;
+
+ spin_lock_irqsave(&vp_dev->lock, flags);
+ list_replace_init(&vp_dev->virtqueues, &virtqueues);
+ spin_unlock_irqrestore(&vp_dev->lock, flags);
+
+ list_for_each_entry(info, &virtqueues, node)
+ vp_del_vq(info->vq);
+}
+
+static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ virtqueue_callback *callbacks[])
+{
+ int i;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = vp_find_vq(vdev, i, callbacks[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ }
+ return 0;
+
+error:
+ vp_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
static struct virtio_config_ops virtio_pci_config_ops = {
.get = vp_get,
.set = vp_set,
.get_status = vp_get_status,
.set_status = vp_set_status,
.reset = vp_reset,
- .find_vq = vp_find_vq,
- .del_vq = vp_del_vq,
+ .find_vqs = vp_find_vqs,
+ .del_vqs = vp_del_vqs,
.get_features = vp_get_features,
.finalize_features = vp_finalize_features,
};
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index bf8ec28..32f6ce8 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -49,15 +49,25 @@
* @set_status: write the status byte
* vdev: the virtio_device
* status: the new status byte
+ * @request_vqs: request the specified number of virtqueues
+ * vdev: the virtio_device
+ * max_vqs: the max number of virtqueues we want
+ * If supplied, must call before any virtqueues are instantiated.
+ * To modify the max number of virtqueues after request_vqs has been
+ * called, call free_vqs and then request_vqs with a new value.
+ * @free_vqs: cleanup resources allocated by request_vqs
+ * vdev: the virtio_device
+ * If supplied, must call after all virtqueues have been deleted.
* @reset: reset the device
* vdev: the virtio device
* After this, status and feature negotiation must be done again
- * @find_vq: find a virtqueue and instantiate it.
+ * @find_vqs: find virtqueues and instantiate them.
* vdev: the virtio_device
- * index: the 0-based virtqueue number in case there's more than one.
- * callback: the virqtueue callback
- * Returns the new virtqueue or ERR_PTR() (eg. -ENOENT).
- * @del_vq: free a virtqueue found by find_vq().
+ * nvqs: the number of virtqueues to find
+ * vqs: on success, includes new virtqueues
+ * callbacks: array of callbacks, for each virtqueue
+ * Returns 0 on success or error status
+ * @del_vqs: free virtqueues found by find_vqs().
* @get_features: get the array of feature bits for this device.
* vdev: the virtio_device
* Returns the first 32 feature bits (all we currently need).
@@ -66,6 +76,7 @@
* This gives the final feature bits for the device: it can change
* the dev->feature bits if it wants.
*/
+typedef void virtqueue_callback(struct virtqueue *);
struct virtio_config_ops
{
void (*get)(struct virtio_device *vdev, unsigned offset,
@@ -75,10 +86,10 @@ struct virtio_config_ops
u8 (*get_status)(struct virtio_device *vdev);
void (*set_status)(struct virtio_device *vdev, u8 status);
void (*reset)(struct virtio_device *vdev);
- struct virtqueue *(*find_vq)(struct virtio_device *vdev,
- unsigned index,
- void (*callback)(struct virtqueue *));
- void (*del_vq)(struct virtqueue *vq);
+ int (*find_vqs)(struct virtio_device *, unsigned nvqs,
+ struct virtqueue *vqs[],
+ virtqueue_callback *callbacks[]);
+ void (*del_vqs)(struct virtio_device *);
u32 (*get_features)(struct virtio_device *vdev);
void (*finalize_features)(struct virtio_device *vdev);
};
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index bb8579a..fd113a1 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -230,6 +230,7 @@ static int p9_virtio_probe(struct virtio_device *vdev)
int err;
struct virtio_chan *chan;
int index;
+ virtqueue_callback *callbacks[] = { req_done };
mutex_lock(&virtio_9p_lock);
index = chan_index++;
@@ -246,11 +247,9 @@ static int p9_virtio_probe(struct virtio_device *vdev)
chan->vdev = vdev;
/* We expect one virtqueue, for requests. */
- chan->vq = vdev->config->find_vq(vdev, 0, req_done);
- if (IS_ERR(chan->vq)) {
- err = PTR_ERR(chan->vq);
+ err = vdev->config->find_vqs(vdev, 1, &chan->vq, callbacks);
+ if (err)
goto out_free_vq;
- }
chan->vq->vdev->priv = chan;
spin_lock_init(&chan->lock);
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-11 22:19 ` [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
@ 2009-05-12 8:55 ` Christian Borntraeger
2009-05-12 8:55 ` Christian Borntraeger
` (2 subsequent siblings)
3 siblings, 0 replies; 22+ messages in thread
From: Christian Borntraeger @ 2009-05-12 8:55 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Carsten Otte, kvm, virtualization, avi, Anthony Liguori
Am Tuesday 12 May 2009 00:19:32 schrieb Michael S. Tsirkin:
> This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
> and updates all drivers. This is needed for MSI support, because MSI
> needs to know the total number of vectors upfront.
[...]
> diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
This file contains several copy/paste breakages and needs at least the
patch below to compile.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
drivers/s390/kvm/kvm_virtio.c | 28 +++++++---------------------
1 file changed, 7 insertions(+), 21 deletions(-)
Index: kvm/drivers/s390/kvm/kvm_virtio.c
===================================================================
--- kvm.orig/drivers/s390/kvm/kvm_virtio.c
+++ kvm/drivers/s390/kvm/kvm_virtio.c
@@ -237,23 +237,23 @@ static void kvm_del_vqs(struct virtio_de
int i;
if (!kdev->vqs)
return;
- for (i = 0; i < ldev->nvqs; ++i)
+ for (i = 0; i < kdev->nvqs; ++i)
kvm_del_vq(kdev->vqs[i]);
- kfree(ldev->vqs);
- ldev->vqs = NULL;
- ldev->nvqs = 0;
+ kfree(kdev->vqs);
+ kdev->vqs = NULL;
+ kdev->nvqs = 0;
}
static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
- struct virtqueue *vqs[]
- void (*callbacks)[](struct virtqueue *))
+ struct virtqueue *vqs[],
+ virtqueue_callback *callbacks[])
{
struct kvm_device *kdev = to_kvmdev(vdev);
int i;
/* We must have this many virtqueues. */
if (nvqs > kdev->desc->num_vq)
- return ERR_PTR(-ENOENT);
+ return -ENOENT;
kdev->vqs = kmalloc(GFP_KERNEL, nvqs * sizeof *kdev->vqs);
if (!kdev->vqs)
@@ -272,20 +272,6 @@ error:
return PTR_ERR(vqs[i]);
}
-static void kvm_del_vqs(struct virtio_device *vdev)
-{
- struct lguest_device *ldev = to_lgdev(vdev);
- int i;
-
- if (!ldev->vqs)
- return;
- for (i = 0; i < ldev->nvqs; ++i)
- lg_del_vq(ldev->vqs[i]);
- kfree(ldev->vqs);
- ldev->vqs = NULL;
- ldev->nvqs = 0;
-}
-
/*
* The config ops structure as defined by virtio config
*/
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-11 22:19 ` [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
2009-05-12 8:55 ` Christian Borntraeger
@ 2009-05-12 8:55 ` Christian Borntraeger
2009-05-12 14:30 ` Rusty Russell
2009-05-12 14:30 ` Rusty Russell
3 siblings, 0 replies; 22+ messages in thread
From: Christian Borntraeger @ 2009-05-12 8:55 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Rusty Russell, virtualization, Anthony Liguori, kvm, avi, Carsten Otte
Am Tuesday 12 May 2009 00:19:32 schrieb Michael S. Tsirkin:
> This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
> and updates all drivers. This is needed for MSI support, because MSI
> needs to know the total number of vectors upfront.
[...]
> diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
This file contains several copy/paste breakages and needs at least the
patch below to compile.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
drivers/s390/kvm/kvm_virtio.c | 28 +++++++---------------------
1 file changed, 7 insertions(+), 21 deletions(-)
Index: kvm/drivers/s390/kvm/kvm_virtio.c
===================================================================
--- kvm.orig/drivers/s390/kvm/kvm_virtio.c
+++ kvm/drivers/s390/kvm/kvm_virtio.c
@@ -237,23 +237,23 @@ static void kvm_del_vqs(struct virtio_de
int i;
if (!kdev->vqs)
return;
- for (i = 0; i < ldev->nvqs; ++i)
+ for (i = 0; i < kdev->nvqs; ++i)
kvm_del_vq(kdev->vqs[i]);
- kfree(ldev->vqs);
- ldev->vqs = NULL;
- ldev->nvqs = 0;
+ kfree(kdev->vqs);
+ kdev->vqs = NULL;
+ kdev->nvqs = 0;
}
static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
- struct virtqueue *vqs[]
- void (*callbacks)[](struct virtqueue *))
+ struct virtqueue *vqs[],
+ virtqueue_callback *callbacks[])
{
struct kvm_device *kdev = to_kvmdev(vdev);
int i;
/* We must have this many virtqueues. */
if (nvqs > kdev->desc->num_vq)
- return ERR_PTR(-ENOENT);
+ return -ENOENT;
kdev->vqs = kmalloc(GFP_KERNEL, nvqs * sizeof *kdev->vqs);
if (!kdev->vqs)
@@ -272,20 +272,6 @@ error:
return PTR_ERR(vqs[i]);
}
-static void kvm_del_vqs(struct virtio_device *vdev)
-{
- struct lguest_device *ldev = to_lgdev(vdev);
- int i;
-
- if (!ldev->vqs)
- return;
- for (i = 0; i < ldev->nvqs; ++i)
- lg_del_vq(ldev->vqs[i]);
- kfree(ldev->vqs);
- ldev->vqs = NULL;
- ldev->nvqs = 0;
-}
-
/*
* The config ops structure as defined by virtio config
*/
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-11 22:19 ` [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
2009-05-12 8:55 ` Christian Borntraeger
2009-05-12 8:55 ` Christian Borntraeger
@ 2009-05-12 14:30 ` Rusty Russell
2009-05-12 14:30 ` Rusty Russell
3 siblings, 0 replies; 22+ messages in thread
From: Rusty Russell @ 2009-05-12 14:30 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Carsten Otte, kvm, virtualization, Christian Borntraeger, avi,
Anthony Liguori
On Tue, 12 May 2009 07:49:32 am Michael S. Tsirkin wrote:
> This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
> and updates all drivers. This is needed for MSI support, because MSI
> needs to know the total number of vectors upfront.
Sorry, is this not on top of my virtio_device vq linked list patch?
Two other things: prefer vq_callback_t as the type name, and perhaps consider
varargs for the callbacks (or would that be too horrible at the implementation
end?)
Thanks,
Rusty.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-11 22:19 ` [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
` (2 preceding siblings ...)
2009-05-12 14:30 ` Rusty Russell
@ 2009-05-12 14:30 ` Rusty Russell
2009-05-12 15:33 ` Michael S. Tsirkin
2009-05-12 15:33 ` Michael S. Tsirkin
3 siblings, 2 replies; 22+ messages in thread
From: Rusty Russell @ 2009-05-12 14:30 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte
On Tue, 12 May 2009 07:49:32 am Michael S. Tsirkin wrote:
> This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
> and updates all drivers. This is needed for MSI support, because MSI
> needs to know the total number of vectors upfront.
Sorry, is this not on top of my virtio_device vq linked list patch?
Two other things: prefer vq_callback_t as the type name, and perhaps consider
varargs for the callbacks (or would that be too horrible at the implementation
end?)
Thanks,
Rusty.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-12 14:30 ` Rusty Russell
@ 2009-05-12 15:33 ` Michael S. Tsirkin
2009-05-12 15:33 ` Michael S. Tsirkin
1 sibling, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-12 15:33 UTC (permalink / raw)
To: Rusty Russell
Cc: Carsten Otte, kvm, virtualization, Christian Borntraeger, avi,
Anthony Liguori
On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote:
> On Tue, 12 May 2009 07:49:32 am Michael S. Tsirkin wrote:
> > This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
> > and updates all drivers. This is needed for MSI support, because MSI
> > needs to know the total number of vectors upfront.
>
> Sorry, is this not on top of my virtio_device vq linked list patch?
Not yet, working on that.
> Two other things: prefer vq_callback_t as the type name,
ok
> and perhaps consider
> varargs for the callbacks (or would that be too horrible at the implementation
> end?)
>
> Thanks,
> Rusty.
Ugh ... I think it will be. And AFAIK gcc generates a lot of code
for varargs - not something we want to do in each interrupt handler.
--
MST
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-12 14:30 ` Rusty Russell
2009-05-12 15:33 ` Michael S. Tsirkin
@ 2009-05-12 15:33 ` Michael S. Tsirkin
2009-05-13 1:17 ` Rusty Russell
2009-05-13 1:17 ` Rusty Russell
1 sibling, 2 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-12 15:33 UTC (permalink / raw)
To: Rusty Russell
Cc: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte
On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote:
> On Tue, 12 May 2009 07:49:32 am Michael S. Tsirkin wrote:
> > This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
> > and updates all drivers. This is needed for MSI support, because MSI
> > needs to know the total number of vectors upfront.
>
> Sorry, is this not on top of my virtio_device vq linked list patch?
Not yet, working on that.
> Two other things: prefer vq_callback_t as the type name,
ok
> and perhaps consider
> varargs for the callbacks (or would that be too horrible at the implementation
> end?)
>
> Thanks,
> Rusty.
Ugh ... I think it will be. And AFAIK gcc generates a lot of code
for varargs - not something we want to do in each interrupt handler.
--
MST
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-12 15:33 ` Michael S. Tsirkin
@ 2009-05-13 1:17 ` Rusty Russell
2009-05-13 7:18 ` Michael S. Tsirkin
2009-05-13 7:18 ` Michael S. Tsirkin
2009-05-13 1:17 ` Rusty Russell
1 sibling, 2 replies; 22+ messages in thread
From: Rusty Russell @ 2009-05-13 1:17 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte
On Wed, 13 May 2009 01:03:30 am Michael S. Tsirkin wrote:
> On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote
> > and perhaps consider
> > varargs for the callbacks (or would that be too horrible at the
> > implementation end?)
> >
> > Thanks,
> > Rusty.
>
> Ugh ... I think it will be. And AFAIK gcc generates a lot of code
> for varargs - not something we want to do in each interrupt handler.
Err, no I mean for find_vqs: eg.
(block device)
err = vdev->config->find_vqs(vdev, 1, &vblk->vq, blk_done);
(net device)
err = vdev->config->find_vqs(vdev, 3, vqs, skb_recv_done, skb_xmit_done, NULL);
A bit neater for for the single-queue case.
Cheers,
Rusty.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-13 1:17 ` Rusty Russell
@ 2009-05-13 7:18 ` Michael S. Tsirkin
2009-05-13 7:18 ` Michael S. Tsirkin
1 sibling, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-13 7:18 UTC (permalink / raw)
To: Rusty Russell
Cc: Carsten Otte, kvm, virtualization, Christian Borntraeger, avi,
Anthony Liguori
On Wed, May 13, 2009 at 10:47:08AM +0930, Rusty Russell wrote:
> On Wed, 13 May 2009 01:03:30 am Michael S. Tsirkin wrote:
> > On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote
> > > and perhaps consider
> > > varargs for the callbacks (or would that be too horrible at the
> > > implementation end?)
> > >
> > > Thanks,
> > > Rusty.
> >
> > Ugh ... I think it will be. And AFAIK gcc generates a lot of code
> > for varargs - not something we want to do in each interrupt handler.
>
> Err, no I mean for find_vqs: eg.
> (block device)
> err = vdev->config->find_vqs(vdev, 1, &vblk->vq, blk_done);
>
> (net device)
> err = vdev->config->find_vqs(vdev, 3, vqs, skb_recv_done, skb_xmit_done, NULL);
>
> A bit neater for for the single-queue case.
>
> Cheers,
> Rusty.
Oh. I see. But it becomes messy now that we also need to pass in the
names, and we lose type safety.
Let's just add a helper function for the single vq case?
static inline struct virtqueue *virtio_find_vq(struct virtio_devide *vdev,
vq_callback_t *c, const char *n)
{
vq_callback_t *callbacks[] = { c };
const char *names[] = { n };
struct virtqueue *vq;
int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
if (err < 0)
return ERR_PTR(err);
return vq;
}
--
MST
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-13 1:17 ` Rusty Russell
2009-05-13 7:18 ` Michael S. Tsirkin
@ 2009-05-13 7:18 ` Michael S. Tsirkin
2009-05-13 7:26 ` Avi Kivity
` (3 more replies)
1 sibling, 4 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-13 7:18 UTC (permalink / raw)
To: Rusty Russell
Cc: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte
On Wed, May 13, 2009 at 10:47:08AM +0930, Rusty Russell wrote:
> On Wed, 13 May 2009 01:03:30 am Michael S. Tsirkin wrote:
> > On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote
> > > and perhaps consider
> > > varargs for the callbacks (or would that be too horrible at the
> > > implementation end?)
> > >
> > > Thanks,
> > > Rusty.
> >
> > Ugh ... I think it will be. And AFAIK gcc generates a lot of code
> > for varargs - not something we want to do in each interrupt handler.
>
> Err, no I mean for find_vqs: eg.
> (block device)
> err = vdev->config->find_vqs(vdev, 1, &vblk->vq, blk_done);
>
> (net device)
> err = vdev->config->find_vqs(vdev, 3, vqs, skb_recv_done, skb_xmit_done, NULL);
>
> A bit neater for for the single-queue case.
>
> Cheers,
> Rusty.
Oh. I see. But it becomes messy now that we also need to pass in the
names, and we lose type safety.
Let's just add a helper function for the single vq case?
static inline struct virtqueue *virtio_find_vq(struct virtio_devide *vdev,
vq_callback_t *c, const char *n)
{
vq_callback_t *callbacks[] = { c };
const char *names[] = { n };
struct virtqueue *vq;
int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
if (err < 0)
return ERR_PTR(err);
return vq;
}
--
MST
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-13 7:18 ` Michael S. Tsirkin
@ 2009-05-13 7:26 ` Avi Kivity
2009-05-13 7:26 ` Avi Kivity
` (2 subsequent siblings)
3 siblings, 0 replies; 22+ messages in thread
From: Avi Kivity @ 2009-05-13 7:26 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Rusty Russell, Christian Borntraeger, virtualization,
Anthony Liguori, kvm, Carsten Otte
Michael S. Tsirkin wrote:
> On Wed, May 13, 2009 at 10:47:08AM +0930, Rusty Russell wrote:
>
>> On Wed, 13 May 2009 01:03:30 am Michael S. Tsirkin wrote:
>>
>>> On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote
>>>
>>>> and perhaps consider
>>>> varargs for the callbacks (or would that be too horrible at the
>>>> implementation end?)
>>>>
>>>> Thanks,
>>>> Rusty.
>>>>
>>> Ugh ... I think it will be. And AFAIK gcc generates a lot of code
>>> for varargs - not something we want to do in each interrupt handler.
>>>
>> Err, no I mean for find_vqs: eg.
>> (block device)
>> err = vdev->config->find_vqs(vdev, 1, &vblk->vq, blk_done);
>>
>> (net device)
>> err = vdev->config->find_vqs(vdev, 3, vqs, skb_recv_done, skb_xmit_done, NULL);
>>
>> A bit neater for for the single-queue case.
>>
>> Cheers,
>> Rusty.
>>
>
> Oh. I see. But it becomes messy now that we also need to pass in the
> names, and we lose type safety.
> Let's just add a helper function for the single vq case?
>
> static inline struct virtqueue *virtio_find_vq(struct virtio_devide *vdev,
> vq_callback_t *c, const char *n)
> {
> vq_callback_t *callbacks[] = { c };
> const char *names[] = { n };
> struct virtqueue *vq;
> int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
> if (err < 0)
> return ERR_PTR(err);
> return vq;
> }
>
Much saner.
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-13 7:18 ` Michael S. Tsirkin
2009-05-13 7:26 ` Avi Kivity
@ 2009-05-13 7:26 ` Avi Kivity
2009-05-13 11:33 ` Rusty Russell
2009-05-13 11:33 ` Rusty Russell
3 siblings, 0 replies; 22+ messages in thread
From: Avi Kivity @ 2009-05-13 7:26 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Carsten Otte, kvm, virtualization, Christian Borntraeger,
Anthony Liguori
Michael S. Tsirkin wrote:
> On Wed, May 13, 2009 at 10:47:08AM +0930, Rusty Russell wrote:
>
>> On Wed, 13 May 2009 01:03:30 am Michael S. Tsirkin wrote:
>>
>>> On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote
>>>
>>>> and perhaps consider
>>>> varargs for the callbacks (or would that be too horrible at the
>>>> implementation end?)
>>>>
>>>> Thanks,
>>>> Rusty.
>>>>
>>> Ugh ... I think it will be. And AFAIK gcc generates a lot of code
>>> for varargs - not something we want to do in each interrupt handler.
>>>
>> Err, no I mean for find_vqs: eg.
>> (block device)
>> err = vdev->config->find_vqs(vdev, 1, &vblk->vq, blk_done);
>>
>> (net device)
>> err = vdev->config->find_vqs(vdev, 3, vqs, skb_recv_done, skb_xmit_done, NULL);
>>
>> A bit neater for for the single-queue case.
>>
>> Cheers,
>> Rusty.
>>
>
> Oh. I see. But it becomes messy now that we also need to pass in the
> names, and we lose type safety.
> Let's just add a helper function for the single vq case?
>
> static inline struct virtqueue *virtio_find_vq(struct virtio_devide *vdev,
> vq_callback_t *c, const char *n)
> {
> vq_callback_t *callbacks[] = { c };
> const char *names[] = { n };
> struct virtqueue *vq;
> int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
> if (err < 0)
> return ERR_PTR(err);
> return vq;
> }
>
Much saner.
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-13 7:18 ` Michael S. Tsirkin
2009-05-13 7:26 ` Avi Kivity
2009-05-13 7:26 ` Avi Kivity
@ 2009-05-13 11:33 ` Rusty Russell
2009-05-13 11:33 ` Rusty Russell
3 siblings, 0 replies; 22+ messages in thread
From: Rusty Russell @ 2009-05-13 11:33 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Carsten Otte, kvm, virtualization, Christian Borntraeger, avi,
Anthony Liguori
On Wed, 13 May 2009 04:48:34 pm Michael S. Tsirkin wrote:
> Let's just add a helper function for the single vq case?
>
> static inline struct virtqueue *virtio_find_vq(struct virtio_devide *vdev,
> vq_callback_t *c, const char *n)
virtio_find_single_vq() to emphasize the singular nature, and it looks good.
Thanks!
Rusty.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-13 7:18 ` Michael S. Tsirkin
` (2 preceding siblings ...)
2009-05-13 11:33 ` Rusty Russell
@ 2009-05-13 11:33 ` Rusty Russell
3 siblings, 0 replies; 22+ messages in thread
From: Rusty Russell @ 2009-05-13 11:33 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte
On Wed, 13 May 2009 04:48:34 pm Michael S. Tsirkin wrote:
> Let's just add a helper function for the single vq case?
>
> static inline struct virtqueue *virtio_find_vq(struct virtio_devide *vdev,
> vq_callback_t *c, const char *n)
virtio_find_single_vq() to emphasize the singular nature, and it looks good.
Thanks!
Rusty.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
2009-05-12 15:33 ` Michael S. Tsirkin
2009-05-13 1:17 ` Rusty Russell
@ 2009-05-13 1:17 ` Rusty Russell
1 sibling, 0 replies; 22+ messages in thread
From: Rusty Russell @ 2009-05-13 1:17 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Carsten Otte, kvm, virtualization, Christian Borntraeger, avi,
Anthony Liguori
On Wed, 13 May 2009 01:03:30 am Michael S. Tsirkin wrote:
> On Wed, May 13, 2009 at 12:00:02AM +0930, Rusty Russell wrote
> > and perhaps consider
> > varargs for the callbacks (or would that be too horrible at the
> > implementation end?)
> >
> > Thanks,
> > Rusty.
>
> Ugh ... I think it will be. And AFAIK gcc generates a lot of code
> for varargs - not something we want to do in each interrupt handler.
Err, no I mean for find_vqs: eg.
(block device)
err = vdev->config->find_vqs(vdev, 1, &vblk->vq, blk_done);
(net device)
err = vdev->config->find_vqs(vdev, 3, vqs, skb_recv_done, skb_xmit_done, NULL);
A bit neater for for the single-queue case.
Cheers,
Rusty.
^ permalink raw reply [flat|nested] 22+ messages in thread
* [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations
[not found] <cover.1242080138.git.mst@redhat.com>
2009-05-11 22:19 ` [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
@ 2009-05-11 22:19 ` Michael S. Tsirkin
2009-05-11 22:19 ` [PATCH 2/3] virtio_pci: split up vp_interrupt Michael S. Tsirkin
` (3 subsequent siblings)
5 siblings, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-11 22:19 UTC (permalink / raw)
To: Christian Borntraeger, Rusty Russell, virtualization, Anthony Liguori
This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
and updates all drivers. This is needed for MSI support, because MSI
needs to know the total number of vectors upfront.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/block/virtio_blk.c | 11 +++---
drivers/char/hw_random/virtio-rng.c | 11 +++---
drivers/char/virtio_console.c | 27 ++++++--------
drivers/lguest/lguest_device.c | 49 +++++++++++++++++++++++++-
drivers/net/virtio_net.c | 48 +++++++++++---------------
drivers/s390/kvm/kvm_virtio.c | 64 +++++++++++++++++++++++++++++++++-
drivers/virtio/virtio_balloon.c | 29 +++++++---------
drivers/virtio/virtio_pci.c | 43 +++++++++++++++++++----
include/linux/virtio_config.h | 29 +++++++++++-----
net/9p/trans_virtio.c | 7 ++--
10 files changed, 225 insertions(+), 93 deletions(-)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 5d34764..7b7435d 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -197,6 +197,7 @@ static int virtblk_probe(struct virtio_device *vdev)
u64 cap;
u32 v;
u32 blk_size, sg_elems;
+ virtqueue_callback *callback[] = { blk_done };
if (index_to_minor(index) >= 1 << MINORBITS)
return -ENOSPC;
@@ -224,11 +225,9 @@ static int virtblk_probe(struct virtio_device *vdev)
sg_init_table(vblk->sg, vblk->sg_elems);
/* We expect one virtqueue, for output. */
- vblk->vq = vdev->config->find_vq(vdev, 0, blk_done);
- if (IS_ERR(vblk->vq)) {
- err = PTR_ERR(vblk->vq);
+ err = vdev->config->find_vqs(vdev, 1, &vblk->vq, callback);
+ if (err)
goto out_free_vblk;
- }
vblk->pool = mempool_create_kmalloc_pool(1,sizeof(struct virtblk_req));
if (!vblk->pool) {
@@ -323,7 +322,7 @@ out_put_disk:
out_mempool:
mempool_destroy(vblk->pool);
out_free_vq:
- vdev->config->del_vq(vblk->vq);
+ vdev->config->del_vqs(vdev);
out_free_vblk:
kfree(vblk);
out:
@@ -344,7 +343,7 @@ static void virtblk_remove(struct virtio_device *vdev)
blk_cleanup_queue(vblk->disk->queue);
put_disk(vblk->disk);
mempool_destroy(vblk->pool);
- vdev->config->del_vq(vblk->vq);
+ vdev->config->del_vqs(vdev);
kfree(vblk);
}
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index 86e83f8..18eabe4 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -91,16 +91,17 @@ static struct hwrng virtio_hwrng = {
static int virtrng_probe(struct virtio_device *vdev)
{
+ virtqueue_callback *callback[] = { random_recv_done };
int err;
/* We expect a single virtqueue. */
- vq = vdev->config->find_vq(vdev, 0, random_recv_done);
- if (IS_ERR(vq))
- return PTR_ERR(vq);
+ err = vdev->config->find_vqs(vdev, 1, &vq, callback);
+ if (err)
+ return err;
err = hwrng_register(&virtio_hwrng);
if (err) {
- vdev->config->del_vq(vq);
+ vdev->config->del_vqs(vdev);
return err;
}
@@ -112,7 +113,7 @@ static void virtrng_remove(struct virtio_device *vdev)
{
vdev->config->reset(vdev);
hwrng_unregister(&virtio_hwrng);
- vdev->config->del_vq(vq);
+ vdev->config->del_vqs(vdev);
}
static struct virtio_device_id id_table[] = {
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index ff6f5a4..1fd5376 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -188,6 +188,8 @@ static void hvc_handle_input(struct virtqueue *vq)
* Finally we put our input buffer in the input queue, ready to receive. */
static int __devinit virtcons_probe(struct virtio_device *dev)
{
+ struct virtqueue *vqs[2];
+ virtqueue_callback *callbacks[2];
int err;
vdev = dev;
@@ -199,20 +201,17 @@ static int __devinit virtcons_probe(struct virtio_device *dev)
goto fail;
}
- /* Find the input queue. */
+ /* Find the queues. */
/* FIXME: This is why we want to wean off hvc: we do nothing
* when input comes in. */
- in_vq = vdev->config->find_vq(vdev, 0, hvc_handle_input);
- if (IS_ERR(in_vq)) {
- err = PTR_ERR(in_vq);
+ callbacks[0] = hvc_handle_input;
+ callbacks[1] = NULL;
+ err = vdev->config->find_vqs(vdev, 2, vqs, callbacks);
+ if (err)
goto free;
- }
- out_vq = vdev->config->find_vq(vdev, 1, NULL);
- if (IS_ERR(out_vq)) {
- err = PTR_ERR(out_vq);
- goto free_in_vq;
- }
+ in_vq = vqs[0];
+ out_vq = vqs[1];
/* Start using the new console output. */
virtio_cons.get_chars = get_chars;
@@ -233,17 +232,15 @@ static int __devinit virtcons_probe(struct virtio_device *dev)
hvc = hvc_alloc(0, 0, &virtio_cons, PAGE_SIZE);
if (IS_ERR(hvc)) {
err = PTR_ERR(hvc);
- goto free_out_vq;
+ goto free_vqs;
}
/* Register the input buffer the first time. */
add_inbuf();
return 0;
-free_out_vq:
- vdev->config->del_vq(out_vq);
-free_in_vq:
- vdev->config->del_vq(in_vq);
+free_vqs:
+ vdev->config->del_vqs(vdev);
free:
kfree(inbuf);
fail:
diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c
index df44d96..53699aa 100644
--- a/drivers/lguest/lguest_device.c
+++ b/drivers/lguest/lguest_device.c
@@ -37,6 +37,10 @@ static inline void lguest_unmap(void *addr)
struct lguest_device {
struct virtio_device vdev;
+ /* Array of virtqueues */
+ struct virtqueue **vqs;
+ int nvqs;
+
/* The entry in the lguest_devices page for this device. */
struct lguest_device_desc *desc;
};
@@ -312,6 +316,47 @@ static void lg_del_vq(struct virtqueue *vq)
kfree(lvq);
}
+static void lg_del_vqs(struct virtio_device *vdev)
+{
+ struct lguest_device *ldev = to_lgdev(vdev);
+ int i;
+ if (!ldev->vqs)
+ return;
+ for (i = 0; i < ldev->nvqs; ++i)
+ lg_del_vq(ldev->vqs[i]);
+ kfree(ldev->vqs);
+ ldev->vqs = NULL;
+ ldev->nvqs = 0;
+}
+
+static int lg_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[]
+ void (*callbacks)[](struct virtqueue *))
+{
+ struct lguest_device *ldev = to_lgdev(vdev);
+ int i;
+
+ /* We must have this many virtqueues. */
+ if (nvqs > ldev->desc->num_vq)
+ return ERR_PTR(-ENOENT);
+
+ ldev->vqs = kmalloc(GFP_KERNEL, nvqs * sizeof *ldev->vqs);
+ if (!ldev->vqs)
+ return -ENOMEM;
+
+ for (i = 0; i < nvqs; ++i) {
+ ldev->vqs[i] = vqs[i] = lg_find_vq(vdev, i, callbacks[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ ldev->nvqs = i;
+ }
+ return 0;
+
+error:
+ vp_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
/* The ops structure which hooks everything together. */
static struct virtio_config_ops lguest_config_ops = {
.get_features = lg_get_features,
@@ -321,8 +366,8 @@ static struct virtio_config_ops lguest_config_ops = {
.get_status = lg_get_status,
.set_status = lg_set_status,
.reset = lg_reset,
- .find_vq = lg_find_vq,
- .del_vq = lg_del_vq,
+ .find_vqs = lg_find_vqs,
+ .del_vqs = lg_del_vqs,
};
/* The root device for the lguest virtio devices. This makes them appear as
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 4d1d479..862a314 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -845,6 +845,9 @@ static int virtnet_probe(struct virtio_device *vdev)
int err;
struct net_device *dev;
struct virtnet_info *vi;
+ struct virtqueue *vqs[3];
+ virtqueue_callback *callbacks[3];
+ int nvqs;
/* Allocate ourselves a network device with room for our info */
dev = alloc_etherdev(sizeof(struct virtnet_info));
@@ -905,25 +908,23 @@ static int virtnet_probe(struct virtio_device *vdev)
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
vi->mergeable_rx_bufs = true;
- /* We expect two virtqueues, receive then send. */
- vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
- if (IS_ERR(vi->rvq)) {
- err = PTR_ERR(vi->rvq);
+ /* We expect two virtqueues, receive then send,
+ * and optionally control. */
+ callbacks[0] = skb_recv_done;
+ callbacks[1] = skb_xmit_done;
+ callbacks[2] = NULL;
+
+ nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
+
+ err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks);
+ if (err)
goto free;
- }
- vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
- if (IS_ERR(vi->svq)) {
- err = PTR_ERR(vi->svq);
- goto free_recv;
- }
+ vi->rvq = vqs[0];
+ vi->svq = vqs[1];
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
- vi->cvq = vdev->config->find_vq(vdev, 2, NULL);
- if (IS_ERR(vi->cvq)) {
- err = PTR_ERR(vi->svq);
- goto free_send;
- }
+ vi->cvq = vqs[2];
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
dev->features |= NETIF_F_HW_VLAN_FILTER;
@@ -941,7 +942,7 @@ static int virtnet_probe(struct virtio_device *vdev)
err = register_netdev(dev);
if (err) {
pr_debug("virtio_net: registering device failed\n");
- goto free_ctrl;
+ goto free_vqs;
}
/* Last of all, set up some receive buffers. */
@@ -962,13 +963,8 @@ static int virtnet_probe(struct virtio_device *vdev)
unregister:
unregister_netdev(dev);
-free_ctrl:
- if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
- vdev->config->del_vq(vi->cvq);
-free_send:
- vdev->config->del_vq(vi->svq);
-free_recv:
- vdev->config->del_vq(vi->rvq);
+free_vqs:
+ vdev->config->del_vqs(vdev);
free:
free_netdev(dev);
return err;
@@ -994,12 +990,10 @@ static void virtnet_remove(struct virtio_device *vdev)
BUG_ON(vi->num != 0);
- vdev->config->del_vq(vi->svq);
- vdev->config->del_vq(vi->rvq);
- if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
- vdev->config->del_vq(vi->cvq);
unregister_netdev(vi->dev);
+ vdev->config->del_vqs(vi->vdev);
+
while (vi->pages)
__free_pages(get_a_page(vi, GFP_KERNEL), 0);
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index cbc8566..6787426 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -34,6 +34,11 @@ static void *kvm_devices;
struct kvm_device {
struct virtio_device vdev;
+
+ /* Array of virtqueues */
+ struct virtqueue **vqs;
+ int nvqs;
+
struct kvm_device_desc *desc;
};
@@ -226,6 +231,61 @@ static void kvm_del_vq(struct virtqueue *vq)
KVM_S390_VIRTIO_RING_ALIGN));
}
+static void kvm_del_vqs(struct virtio_device *vdev)
+{
+ struct kvm_device *kdev = to_kvmdev(vdev);
+ int i;
+ if (!kdev->vqs)
+ return;
+ for (i = 0; i < ldev->nvqs; ++i)
+ kvm_del_vq(kdev->vqs[i]);
+ kfree(ldev->vqs);
+ ldev->vqs = NULL;
+ ldev->nvqs = 0;
+}
+
+static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[]
+ void (*callbacks)[](struct virtqueue *))
+{
+ struct kvm_device *kdev = to_kvmdev(vdev);
+ int i;
+
+ /* We must have this many virtqueues. */
+ if (nvqs > kdev->desc->num_vq)
+ return ERR_PTR(-ENOENT);
+
+ kdev->vqs = kmalloc(GFP_KERNEL, nvqs * sizeof *kdev->vqs);
+ if (!kdev->vqs)
+ return -ENOMEM;
+
+ for (i = 0; i < nvqs; ++i) {
+ kdev->vqs[i] = vqs[i] = kvm_find_vq(vdev, i, callbacks[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ kdev->nvqs = i;
+ }
+ return 0;
+
+error:
+ kvm_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
+static void kvm_del_vqs(struct virtio_device *vdev)
+{
+ struct lguest_device *ldev = to_lgdev(vdev);
+ int i;
+
+ if (!ldev->vqs)
+ return;
+ for (i = 0; i < ldev->nvqs; ++i)
+ lg_del_vq(ldev->vqs[i]);
+ kfree(ldev->vqs);
+ ldev->vqs = NULL;
+ ldev->nvqs = 0;
+}
+
/*
* The config ops structure as defined by virtio config
*/
@@ -237,8 +297,8 @@ static struct virtio_config_ops kvm_vq_configspace_ops = {
.get_status = kvm_get_status,
.set_status = kvm_set_status,
.reset = kvm_reset,
- .find_vq = kvm_find_vq,
- .del_vq = kvm_del_vq,
+ .find_vqs = kvm_find_vqs,
+ .del_vqs = kvm_del_vqs,
};
/*
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 9c76a06..ef7c481 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -204,6 +204,8 @@ static int balloon(void *_vballoon)
static int virtballoon_probe(struct virtio_device *vdev)
{
struct virtio_balloon *vb;
+ struct virtqueue *vqs[2];
+ virtqueue_callback *callbacks[2];
int err;
vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
@@ -218,22 +220,20 @@ static int virtballoon_probe(struct virtio_device *vdev)
vb->vdev = vdev;
/* We expect two virtqueues. */
- vb->inflate_vq = vdev->config->find_vq(vdev, 0, balloon_ack);
- if (IS_ERR(vb->inflate_vq)) {
- err = PTR_ERR(vb->inflate_vq);
+ callbacks[0] = balloon_ack;
+ callbacks[1] = balloon_ack;
+
+ err = vdev->config->find_vqs(vdev, 2, vqs, callbacks);
+ if (err)
goto out_free_vb;
- }
- vb->deflate_vq = vdev->config->find_vq(vdev, 1, balloon_ack);
- if (IS_ERR(vb->deflate_vq)) {
- err = PTR_ERR(vb->deflate_vq);
- goto out_del_inflate_vq;
- }
+ vb->inflate_vq = vqs[0];
+ vb->deflate_vq = vqs[1];
vb->thread = kthread_run(balloon, vb, "vballoon");
if (IS_ERR(vb->thread)) {
err = PTR_ERR(vb->thread);
- goto out_del_deflate_vq;
+ goto out_del_vqs;
}
vb->tell_host_first
@@ -241,10 +241,8 @@ static int virtballoon_probe(struct virtio_device *vdev)
return 0;
-out_del_deflate_vq:
- vdev->config->del_vq(vb->deflate_vq);
-out_del_inflate_vq:
- vdev->config->del_vq(vb->inflate_vq);
+out_del_vqs:
+ vdev->config->del_vqs(vdev);
out_free_vb:
kfree(vb);
out:
@@ -264,8 +262,7 @@ static void virtballoon_remove(struct virtio_device *vdev)
/* Now we reset the device so we can clean up the queues. */
vdev->config->reset(vdev);
- vdev->config->del_vq(vb->deflate_vq);
- vdev->config->del_vq(vb->inflate_vq);
+ vdev->config->del_vqs(vdev);
kfree(vb);
}
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 330aacb..d5e030f 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -275,11 +275,7 @@ static void vp_del_vq(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
struct virtio_pci_vq_info *info = vq->priv;
- unsigned long flags, size;
-
- spin_lock_irqsave(&vp_dev->lock, flags);
- list_del(&info->node);
- spin_unlock_irqrestore(&vp_dev->lock, flags);
+ unsigned long size;
vring_del_virtqueue(vq);
@@ -292,14 +288,47 @@ static void vp_del_vq(struct virtqueue *vq)
kfree(info);
}
+static void vp_del_vqs(struct virtio_device *vdev)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ struct virtio_pci_vq_info *info;
+ struct list_head virtqueues;
+ unsigned long flags;
+
+ spin_lock_irqsave(&vp_dev->lock, flags);
+ list_replace_init(&vp_dev->virtqueues, &virtqueues);
+ spin_unlock_irqrestore(&vp_dev->lock, flags);
+
+ list_for_each_entry(info, &virtqueues, node)
+ vp_del_vq(info->vq);
+}
+
+static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ virtqueue_callback *callbacks[])
+{
+ int i;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = vp_find_vq(vdev, i, callbacks[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ }
+ return 0;
+
+error:
+ vp_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
static struct virtio_config_ops virtio_pci_config_ops = {
.get = vp_get,
.set = vp_set,
.get_status = vp_get_status,
.set_status = vp_set_status,
.reset = vp_reset,
- .find_vq = vp_find_vq,
- .del_vq = vp_del_vq,
+ .find_vqs = vp_find_vqs,
+ .del_vqs = vp_del_vqs,
.get_features = vp_get_features,
.finalize_features = vp_finalize_features,
};
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index bf8ec28..32f6ce8 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -49,15 +49,25 @@
* @set_status: write the status byte
* vdev: the virtio_device
* status: the new status byte
+ * @request_vqs: request the specified number of virtqueues
+ * vdev: the virtio_device
+ * max_vqs: the max number of virtqueues we want
+ * If supplied, must call before any virtqueues are instantiated.
+ * To modify the max number of virtqueues after request_vqs has been
+ * called, call free_vqs and then request_vqs with a new value.
+ * @free_vqs: cleanup resources allocated by request_vqs
+ * vdev: the virtio_device
+ * If supplied, must call after all virtqueues have been deleted.
* @reset: reset the device
* vdev: the virtio device
* After this, status and feature negotiation must be done again
- * @find_vq: find a virtqueue and instantiate it.
+ * @find_vqs: find virtqueues and instantiate them.
* vdev: the virtio_device
- * index: the 0-based virtqueue number in case there's more than one.
- * callback: the virqtueue callback
- * Returns the new virtqueue or ERR_PTR() (eg. -ENOENT).
- * @del_vq: free a virtqueue found by find_vq().
+ * nvqs: the number of virtqueues to find
+ * vqs: on success, includes new virtqueues
+ * callbacks: array of callbacks, for each virtqueue
+ * Returns 0 on success or error status
+ * @del_vqs: free virtqueues found by find_vqs().
* @get_features: get the array of feature bits for this device.
* vdev: the virtio_device
* Returns the first 32 feature bits (all we currently need).
@@ -66,6 +76,7 @@
* This gives the final feature bits for the device: it can change
* the dev->feature bits if it wants.
*/
+typedef void virtqueue_callback(struct virtqueue *);
struct virtio_config_ops
{
void (*get)(struct virtio_device *vdev, unsigned offset,
@@ -75,10 +86,10 @@ struct virtio_config_ops
u8 (*get_status)(struct virtio_device *vdev);
void (*set_status)(struct virtio_device *vdev, u8 status);
void (*reset)(struct virtio_device *vdev);
- struct virtqueue *(*find_vq)(struct virtio_device *vdev,
- unsigned index,
- void (*callback)(struct virtqueue *));
- void (*del_vq)(struct virtqueue *vq);
+ int (*find_vqs)(struct virtio_device *, unsigned nvqs,
+ struct virtqueue *vqs[],
+ virtqueue_callback *callbacks[]);
+ void (*del_vqs)(struct virtio_device *);
u32 (*get_features)(struct virtio_device *vdev);
void (*finalize_features)(struct virtio_device *vdev);
};
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index bb8579a..fd113a1 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -230,6 +230,7 @@ static int p9_virtio_probe(struct virtio_device *vdev)
int err;
struct virtio_chan *chan;
int index;
+ virtqueue_callback *callbacks[] = { req_done };
mutex_lock(&virtio_9p_lock);
index = chan_index++;
@@ -246,11 +247,9 @@ static int p9_virtio_probe(struct virtio_device *vdev)
chan->vdev = vdev;
/* We expect one virtqueue, for requests. */
- chan->vq = vdev->config->find_vq(vdev, 0, req_done);
- if (IS_ERR(chan->vq)) {
- err = PTR_ERR(chan->vq);
+ err = vdev->config->find_vqs(vdev, 1, &chan->vq, callbacks);
+ if (err)
goto out_free_vq;
- }
chan->vq->vdev->priv = chan;
spin_lock_init(&chan->lock);
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH 2/3] virtio_pci: split up vp_interrupt
[not found] <cover.1242080138.git.mst@redhat.com>
2009-05-11 22:19 ` [PATCH 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
2009-05-11 22:19 ` Michael S. Tsirkin
@ 2009-05-11 22:19 ` Michael S. Tsirkin
2009-05-11 22:19 ` Michael S. Tsirkin
` (2 subsequent siblings)
5 siblings, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-11 22:19 UTC (permalink / raw)
To: Christian Borntraeger, Rusty Russell, virtualization,
Anthony Liguori, kvm
This reorganizes virtio-pci code in vp_interrupt slightly, so that
it's easier to add per-vq MSI support on top.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/virtio/virtio_pci.c | 53 +++++++++++++++++++++++++++---------------
1 files changed, 34 insertions(+), 19 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index d5e030f..a6bebe2 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -164,6 +164,37 @@ static void vp_notify(struct virtqueue *vq)
iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
}
+/* Handle a configuration change: Tell driver if it wants to know. */
+static irqreturn_t vp_config_changed(int irq, void *opaque)
+{
+ struct virtio_pci_device *vp_dev = opaque;
+ struct virtio_driver *drv;
+ drv = container_of(vp_dev->vdev.dev.driver,
+ struct virtio_driver, driver);
+
+ if (drv && drv->config_changed)
+ drv->config_changed(&vp_dev->vdev);
+ return IRQ_HANDLED;
+}
+
+/* Notify all virtqueues on an interrupt. */
+static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
+{
+ struct virtio_pci_device *vp_dev = opaque;
+ struct virtio_pci_vq_info *info;
+ irqreturn_t ret = IRQ_NONE;
+ unsigned long flags;
+
+ spin_lock_irqsave(&vp_dev->lock, flags);
+ list_for_each_entry(info, &vp_dev->virtqueues, node) {
+ if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
+ ret = IRQ_HANDLED;
+ }
+ spin_unlock_irqrestore(&vp_dev->lock, flags);
+
+ return ret;
+}
+
/* A small wrapper to also acknowledge the interrupt when it's handled.
* I really need an EIO hook for the vring so I can ack the interrupt once we
* know that we'll be handling the IRQ but before we invoke the callback since
@@ -173,9 +204,6 @@ static void vp_notify(struct virtqueue *vq)
static irqreturn_t vp_interrupt(int irq, void *opaque)
{
struct virtio_pci_device *vp_dev = opaque;
- struct virtio_pci_vq_info *info;
- irqreturn_t ret = IRQ_NONE;
- unsigned long flags;
u8 isr;
/* reading the ISR has the effect of also clearing it so it's very
@@ -187,23 +215,10 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
return IRQ_NONE;
/* Configuration change? Tell driver if it wants to know. */
- if (isr & VIRTIO_PCI_ISR_CONFIG) {
- struct virtio_driver *drv;
- drv = container_of(vp_dev->vdev.dev.driver,
- struct virtio_driver, driver);
-
- if (drv && drv->config_changed)
- drv->config_changed(&vp_dev->vdev);
- }
+ if (isr & VIRTIO_PCI_ISR_CONFIG)
+ vp_config_changed(irq, opaque);
- spin_lock_irqsave(&vp_dev->lock, flags);
- list_for_each_entry(info, &vp_dev->virtqueues, node) {
- if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
- ret = IRQ_HANDLED;
- }
- spin_unlock_irqrestore(&vp_dev->lock, flags);
-
- return ret;
+ return vp_vring_interrupt(irq, opaque);
}
/* the config->find_vq() implementation */
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH 2/3] virtio_pci: split up vp_interrupt
[not found] <cover.1242080138.git.mst@redhat.com>
` (2 preceding siblings ...)
2009-05-11 22:19 ` [PATCH 2/3] virtio_pci: split up vp_interrupt Michael S. Tsirkin
@ 2009-05-11 22:19 ` Michael S. Tsirkin
2009-05-11 22:19 ` [PATCH 3/3] virtio_pci: optional MSI-X support Michael S. Tsirkin
2009-05-11 22:19 ` Michael S. Tsirkin
5 siblings, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-11 22:19 UTC (permalink / raw)
To: Christian Borntraeger, Rusty Russell, virtualization, Anthony Liguori
This reorganizes virtio-pci code in vp_interrupt slightly, so that
it's easier to add per-vq MSI support on top.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/virtio/virtio_pci.c | 53 +++++++++++++++++++++++++++---------------
1 files changed, 34 insertions(+), 19 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index d5e030f..a6bebe2 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -164,6 +164,37 @@ static void vp_notify(struct virtqueue *vq)
iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
}
+/* Handle a configuration change: Tell driver if it wants to know. */
+static irqreturn_t vp_config_changed(int irq, void *opaque)
+{
+ struct virtio_pci_device *vp_dev = opaque;
+ struct virtio_driver *drv;
+ drv = container_of(vp_dev->vdev.dev.driver,
+ struct virtio_driver, driver);
+
+ if (drv && drv->config_changed)
+ drv->config_changed(&vp_dev->vdev);
+ return IRQ_HANDLED;
+}
+
+/* Notify all virtqueues on an interrupt. */
+static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
+{
+ struct virtio_pci_device *vp_dev = opaque;
+ struct virtio_pci_vq_info *info;
+ irqreturn_t ret = IRQ_NONE;
+ unsigned long flags;
+
+ spin_lock_irqsave(&vp_dev->lock, flags);
+ list_for_each_entry(info, &vp_dev->virtqueues, node) {
+ if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
+ ret = IRQ_HANDLED;
+ }
+ spin_unlock_irqrestore(&vp_dev->lock, flags);
+
+ return ret;
+}
+
/* A small wrapper to also acknowledge the interrupt when it's handled.
* I really need an EIO hook for the vring so I can ack the interrupt once we
* know that we'll be handling the IRQ but before we invoke the callback since
@@ -173,9 +204,6 @@ static void vp_notify(struct virtqueue *vq)
static irqreturn_t vp_interrupt(int irq, void *opaque)
{
struct virtio_pci_device *vp_dev = opaque;
- struct virtio_pci_vq_info *info;
- irqreturn_t ret = IRQ_NONE;
- unsigned long flags;
u8 isr;
/* reading the ISR has the effect of also clearing it so it's very
@@ -187,23 +215,10 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
return IRQ_NONE;
/* Configuration change? Tell driver if it wants to know. */
- if (isr & VIRTIO_PCI_ISR_CONFIG) {
- struct virtio_driver *drv;
- drv = container_of(vp_dev->vdev.dev.driver,
- struct virtio_driver, driver);
-
- if (drv && drv->config_changed)
- drv->config_changed(&vp_dev->vdev);
- }
+ if (isr & VIRTIO_PCI_ISR_CONFIG)
+ vp_config_changed(irq, opaque);
- spin_lock_irqsave(&vp_dev->lock, flags);
- list_for_each_entry(info, &vp_dev->virtqueues, node) {
- if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
- ret = IRQ_HANDLED;
- }
- spin_unlock_irqrestore(&vp_dev->lock, flags);
-
- return ret;
+ return vp_vring_interrupt(irq, opaque);
}
/* the config->find_vq() implementation */
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH 3/3] virtio_pci: optional MSI-X support
[not found] <cover.1242080138.git.mst@redhat.com>
` (3 preceding siblings ...)
2009-05-11 22:19 ` Michael S. Tsirkin
@ 2009-05-11 22:19 ` Michael S. Tsirkin
2009-05-11 22:19 ` Michael S. Tsirkin
5 siblings, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-11 22:19 UTC (permalink / raw)
To: Christian Borntraeger, Rusty Russell, virtualization,
Anthony Liguori, kvm
This implements optional MSI-X support in virtio_pci.
MSI-X is used whenever the host supports at least 2 MSI-X
vectors: 1 for configuration changes and 1 for virtqueues.
Per-virtqueue vectors are allocated if enough vectors
available.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/virtio/virtio_pci.c | 211 +++++++++++++++++++++++++++++++++++++++----
include/linux/virtio_pci.h | 8 ++-
2 files changed, 199 insertions(+), 20 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index a6bebe2..d21e2e6 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -42,6 +42,29 @@ struct virtio_pci_device
/* a list of queues so we can dispatch IRQs */
spinlock_t lock;
struct list_head virtqueues;
+
+ /* MSI-X support */
+ int msix_enabled;
+ int intx_enabled;
+ struct msix_entry *msix_entries;
+ /* Name strings for interrupts. This size should be enough,
+ * and I'm too lazy to allocate each name separately. */
+ char (*msix_names)[256];
+ /* Number of vectors configured at startup (excludes per-virtqueue
+ * vectors if any) */
+ unsigned msix_preset_vectors;
+ /* Number of per-virtqueue vectors if any. */
+ unsigned msix_per_vq_vectors;
+};
+
+/* Constants for MSI-X */
+/* Use first vector for configuration changes, second and the rest for
+ * virtqueues Thus, we need at least 2 vectors for MSI. */
+enum {
+ VP_MSIX_CONFIG_VECTOR = 0,
+ VP_MSIX_VQ_VECTOR = 1,
+ VP_MSIX_MIN_VECTORS = 2,
+ VP_MSIX_NO_VECTOR = 0xffff,
};
struct virtio_pci_vq_info
@@ -60,6 +83,9 @@ struct virtio_pci_vq_info
/* the list node for the virtqueues list */
struct list_head node;
+
+ /* MSI-X vector (or none) */
+ unsigned vector;
};
/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
@@ -109,7 +135,8 @@ static void vp_get(struct virtio_device *vdev, unsigned offset,
void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void __iomem *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ void __iomem *ioaddr = vp_dev->ioaddr +
+ VIRTIO_PCI_CONFIG(vp_dev) + offset;
u8 *ptr = buf;
int i;
@@ -123,7 +150,8 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
const void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void __iomem *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ void __iomem *ioaddr = vp_dev->ioaddr +
+ VIRTIO_PCI_CONFIG(vp_dev) + offset;
const u8 *ptr = buf;
int i;
@@ -221,7 +249,116 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
return vp_vring_interrupt(irq, opaque);
}
-/* the config->find_vq() implementation */
+static void vp_free_vectors(struct virtio_device *vdev) {
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ int i;
+
+ if (vp_dev->intx_enabled) {
+ free_irq(vp_dev->pci_dev->irq, vp_dev);
+ vp_dev->intx_enabled = 0;
+ }
+
+ for (i = 0; i < vp_dev->msix_preset_vectors; ++i)
+ free_irq(vp_dev->msix_entries[i].vector, vp_dev);
+ vp_dev->msix_preset_vectors = 0;
+
+ if (vp_dev->msix_enabled) {
+ /* Disable the vector used for configuration */
+ iowrite16(VP_MSIX_NO_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+
+ vp_dev->msix_enabled = 0;
+ pci_disable_msix(vp_dev->pci_dev);
+ }
+}
+
+static int vp_request_vectors(struct virtio_device *vdev, unsigned max_vqs)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ const char *name = dev_name(&vp_dev->vdev.dev);
+ unsigned i, vectors;
+ int err = -ENOMEM;
+
+ /* We need at most one vector per queue and one for config changes */
+ vectors = VP_MSIX_VQ_VECTOR + max_vqs;
+ vp_dev->msix_entries = kmalloc(vectors * sizeof *vp_dev->msix_entries,
+ GFP_KERNEL);
+ if (!vp_dev->msix_entries)
+ goto error_entries;
+ vp_dev->msix_names = kmalloc(vectors * sizeof *vp_dev->msix_names,
+ GFP_KERNEL);
+ if (!vp_dev->msix_names)
+ goto error_names;
+
+ snprintf(vp_dev->msix_names[VP_MSIX_CONFIG_VECTOR],
+ sizeof *vp_dev->msix_names, "%s-config", name);
+ for (i = 0; i < max_vqs; ++i)
+ snprintf(vp_dev->msix_names[i + VP_MSIX_VQ_VECTOR],
+ sizeof *vp_dev->msix_names, "%s-vq-%d", name, i);
+ for (i = 0; i < vectors; ++i)
+ vp_dev->msix_entries[i].entry = i;
+
+ vp_dev->msix_preset_vectors = 1;
+ vp_dev->msix_per_vq_vectors = max_vqs;
+ for (;;) {
+ err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries,
+ vectors);
+ /* Error out if not enough vectors */
+ if (err > 0 && err < VP_MSIX_MIN_VECTORS)
+ err = -EBUSY;
+ if (err <= 0)
+ break;
+ /* Not enough vectors for all queues. Retry, disabling
+ * per-queue interrupts */
+ vectors = VP_MSIX_MIN_VECTORS;
+ vp_dev->msix_preset_vectors = VP_MSIX_MIN_VECTORS;
+ vp_dev->msix_per_vq_vectors = 0;
+ snprintf(vp_dev->msix_names[VP_MSIX_VQ_VECTOR],
+ sizeof *vp_dev->msix_names, "%s-vq", name);
+ }
+
+ if (!err)
+ vp_dev->msix_enabled = 1;
+ if (err) {
+ /* Can't allocate enough MSI-X vectors, use regular interrupt */
+ vp_dev->msix_enabled = 0;
+ vp_dev->msix_preset_vectors = 0;
+ vp_dev->msix_per_vq_vectors = 0;
+ /* Register a handler for the queue with the PCI device's
+ * interrupt */
+ err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
+ IRQF_SHARED, name, vp_dev);
+ if (err)
+ goto error_irq;
+ vp_dev->intx_enabled = 1;
+ }
+ for (i = 0; i < vp_dev->msix_preset_vectors; ++i) {
+ err = request_irq(vp_dev->msix_entries[i].vector,
+ i == VP_MSIX_CONFIG_VECTOR ?
+ vp_config_changed : vp_vring_interrupt,
+ 0, vp_dev->msix_names[i], vp_dev);
+ if (err) {
+ /* Set msix_preset_vectors so that only vectors we
+ * already allocated will be freed by vp_free_vqs. */
+ vp_dev->msix_preset_vectors = i;
+ goto error_irq;
+ }
+
+ /* Set the vector used for configuration */
+ if (i == VP_MSIX_CONFIG_VECTOR)
+ iowrite16(VP_MSIX_CONFIG_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+ }
+ return 0;
+error_irq:
+ vp_free_vectors(vdev);
+ kfree(vp_dev->msix_names);
+error_names:
+ kfree(vp_dev->msix_entries);
+error_entries:
+ return err;
+}
+
static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
void (*callback)(struct virtqueue *vq))
{
@@ -229,7 +366,7 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
struct virtio_pci_vq_info *info;
struct virtqueue *vq;
unsigned long flags, size;
- u16 num;
+ u16 num, vector;
int err;
/* Select the queue we're interested in */
@@ -248,6 +385,7 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
info->queue_index = index;
info->num = num;
+ info->vector = VP_MSIX_NO_VECTOR;
size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
@@ -271,12 +409,29 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
vq->priv = info;
info->vq = vq;
+ /* allocate per-vq vector if available and necessary */
+ if (vp_dev->msix_per_vq_vectors && callback) {
+ vector = VP_MSIX_VQ_VECTOR + vp_dev->msix_per_vq_vectors - 1;
+ err = request_irq(vp_dev->msix_entries[vector].vector,
+ vring_interrupt, 0,
+ vp_dev->msix_names[vector], vq);
+ if (err)
+ goto out_request_irq;
+ info->vector = vector;
+ vp_dev->msix_per_vq_vectors--;
+ iowrite16(vector, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+ } else if (vp_dev->msix_enabled)
+ iowrite16(VP_MSIX_VQ_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+
spin_lock_irqsave(&vp_dev->lock, flags);
list_add(&info->node, &vp_dev->virtqueues);
spin_unlock_irqrestore(&vp_dev->lock, flags);
return vq;
+out_request_irq:
+ vring_del_virtqueue(vq);
out_activate_queue:
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
free_pages_exact(info->queue, size);
@@ -285,17 +440,27 @@ out_info:
return ERR_PTR(err);
}
-/* the config->del_vq() implementation */
static void vp_del_vq(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
struct virtio_pci_vq_info *info = vq->priv;
unsigned long size;
+ iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
+
+ if (info->vector != VP_MSIX_NO_VECTOR)
+ free_irq(vp_dev->msix_entries[info->vector].vector, vq);
+
+ if (vp_dev->msix_enabled) {
+ iowrite16(VP_MSIX_NO_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+ /* Flush the write out to device */
+ ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
+ }
+
vring_del_virtqueue(vq);
/* Select and deactivate the queue */
- iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN));
@@ -303,6 +468,7 @@ static void vp_del_vq(struct virtqueue *vq)
kfree(info);
}
+/* the config->del_vqs() implementation */
static void vp_del_vqs(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -316,23 +482,38 @@ static void vp_del_vqs(struct virtio_device *vdev)
list_for_each_entry(info, &virtqueues, node)
vp_del_vq(info->vq);
+
+ vp_free_vectors(vdev);
}
+/* the config->find_vqs() implementation */
static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct virtqueue *vqs[],
virtqueue_callback *callbacks[])
{
- int i;
+ int vectors = 0;
+ int i, err;
+
+ /* How many vectors would we like? */
+ for (i = 0; i < nvqs; ++i)
+ if (callbacks[i])
+ ++vectors;
+
+ err = vp_request_vectors(vdev, vectors);
+ if (err)
+ goto error_request;
for (i = 0; i < nvqs; ++i) {
vqs[i] = vp_find_vq(vdev, i, callbacks[i]);
if (IS_ERR(vqs[i]))
- goto error;
+ goto error_find;
}
return 0;
-error:
+error_find:
vp_del_vqs(vdev);
+
+error_request:
return PTR_ERR(vqs[i]);
}
@@ -354,7 +535,7 @@ static void virtio_pci_release_dev(struct device *_d)
struct virtio_pci_device *vp_dev = to_vp_device(dev);
struct pci_dev *pci_dev = vp_dev->pci_dev;
- free_irq(pci_dev->irq, vp_dev);
+ vp_del_vqs(dev);
pci_set_drvdata(pci_dev, NULL);
pci_iounmap(pci_dev, vp_dev->ioaddr);
pci_release_regions(pci_dev);
@@ -413,21 +594,13 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
vp_dev->vdev.id.device = pci_dev->subsystem_device;
- /* register a handler for the queue with the PCI device's interrupt */
- err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
- dev_name(&vp_dev->vdev.dev), vp_dev);
- if (err)
- goto out_set_drvdata;
-
/* finally register the virtio device */
err = register_virtio_device(&vp_dev->vdev);
if (err)
- goto out_req_irq;
+ goto out_set_drvdata;
return 0;
-out_req_irq:
- free_irq(pci_dev->irq, vp_dev);
out_set_drvdata:
pci_set_drvdata(pci_dev, NULL);
pci_iounmap(pci_dev, vp_dev->ioaddr);
diff --git a/include/linux/virtio_pci.h b/include/linux/virtio_pci.h
index cd0fd5d..4a0275b 100644
--- a/include/linux/virtio_pci.h
+++ b/include/linux/virtio_pci.h
@@ -47,9 +47,15 @@
/* The bit of the ISR which indicates a device configuration change. */
#define VIRTIO_PCI_ISR_CONFIG 0x2
+/* MSI-X registers: only enabled if MSI-X is enabled. */
+/* A 16-bit vector for configuration changes. */
+#define VIRTIO_MSI_CONFIG_VECTOR 20
+/* A 16-bit vector for selected queue notifications. */
+#define VIRTIO_MSI_QUEUE_VECTOR 22
+
/* The remaining space is defined by each driver as the per-driver
* configuration space */
-#define VIRTIO_PCI_CONFIG 20
+#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20)
/* Virtio ABI version, this must match exactly */
#define VIRTIO_PCI_ABI_VERSION 0
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH 3/3] virtio_pci: optional MSI-X support
[not found] <cover.1242080138.git.mst@redhat.com>
` (4 preceding siblings ...)
2009-05-11 22:19 ` [PATCH 3/3] virtio_pci: optional MSI-X support Michael S. Tsirkin
@ 2009-05-11 22:19 ` Michael S. Tsirkin
5 siblings, 0 replies; 22+ messages in thread
From: Michael S. Tsirkin @ 2009-05-11 22:19 UTC (permalink / raw)
To: Christian Borntraeger, Rusty Russell, virtualization, Anthony Liguori
This implements optional MSI-X support in virtio_pci.
MSI-X is used whenever the host supports at least 2 MSI-X
vectors: 1 for configuration changes and 1 for virtqueues.
Per-virtqueue vectors are allocated if enough vectors
available.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/virtio/virtio_pci.c | 211 +++++++++++++++++++++++++++++++++++++++----
include/linux/virtio_pci.h | 8 ++-
2 files changed, 199 insertions(+), 20 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index a6bebe2..d21e2e6 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -42,6 +42,29 @@ struct virtio_pci_device
/* a list of queues so we can dispatch IRQs */
spinlock_t lock;
struct list_head virtqueues;
+
+ /* MSI-X support */
+ int msix_enabled;
+ int intx_enabled;
+ struct msix_entry *msix_entries;
+ /* Name strings for interrupts. This size should be enough,
+ * and I'm too lazy to allocate each name separately. */
+ char (*msix_names)[256];
+ /* Number of vectors configured at startup (excludes per-virtqueue
+ * vectors if any) */
+ unsigned msix_preset_vectors;
+ /* Number of per-virtqueue vectors if any. */
+ unsigned msix_per_vq_vectors;
+};
+
+/* Constants for MSI-X */
+/* Use first vector for configuration changes, second and the rest for
+ * virtqueues Thus, we need at least 2 vectors for MSI. */
+enum {
+ VP_MSIX_CONFIG_VECTOR = 0,
+ VP_MSIX_VQ_VECTOR = 1,
+ VP_MSIX_MIN_VECTORS = 2,
+ VP_MSIX_NO_VECTOR = 0xffff,
};
struct virtio_pci_vq_info
@@ -60,6 +83,9 @@ struct virtio_pci_vq_info
/* the list node for the virtqueues list */
struct list_head node;
+
+ /* MSI-X vector (or none) */
+ unsigned vector;
};
/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
@@ -109,7 +135,8 @@ static void vp_get(struct virtio_device *vdev, unsigned offset,
void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void __iomem *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ void __iomem *ioaddr = vp_dev->ioaddr +
+ VIRTIO_PCI_CONFIG(vp_dev) + offset;
u8 *ptr = buf;
int i;
@@ -123,7 +150,8 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
const void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void __iomem *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ void __iomem *ioaddr = vp_dev->ioaddr +
+ VIRTIO_PCI_CONFIG(vp_dev) + offset;
const u8 *ptr = buf;
int i;
@@ -221,7 +249,116 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
return vp_vring_interrupt(irq, opaque);
}
-/* the config->find_vq() implementation */
+static void vp_free_vectors(struct virtio_device *vdev) {
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ int i;
+
+ if (vp_dev->intx_enabled) {
+ free_irq(vp_dev->pci_dev->irq, vp_dev);
+ vp_dev->intx_enabled = 0;
+ }
+
+ for (i = 0; i < vp_dev->msix_preset_vectors; ++i)
+ free_irq(vp_dev->msix_entries[i].vector, vp_dev);
+ vp_dev->msix_preset_vectors = 0;
+
+ if (vp_dev->msix_enabled) {
+ /* Disable the vector used for configuration */
+ iowrite16(VP_MSIX_NO_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+
+ vp_dev->msix_enabled = 0;
+ pci_disable_msix(vp_dev->pci_dev);
+ }
+}
+
+static int vp_request_vectors(struct virtio_device *vdev, unsigned max_vqs)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ const char *name = dev_name(&vp_dev->vdev.dev);
+ unsigned i, vectors;
+ int err = -ENOMEM;
+
+ /* We need at most one vector per queue and one for config changes */
+ vectors = VP_MSIX_VQ_VECTOR + max_vqs;
+ vp_dev->msix_entries = kmalloc(vectors * sizeof *vp_dev->msix_entries,
+ GFP_KERNEL);
+ if (!vp_dev->msix_entries)
+ goto error_entries;
+ vp_dev->msix_names = kmalloc(vectors * sizeof *vp_dev->msix_names,
+ GFP_KERNEL);
+ if (!vp_dev->msix_names)
+ goto error_names;
+
+ snprintf(vp_dev->msix_names[VP_MSIX_CONFIG_VECTOR],
+ sizeof *vp_dev->msix_names, "%s-config", name);
+ for (i = 0; i < max_vqs; ++i)
+ snprintf(vp_dev->msix_names[i + VP_MSIX_VQ_VECTOR],
+ sizeof *vp_dev->msix_names, "%s-vq-%d", name, i);
+ for (i = 0; i < vectors; ++i)
+ vp_dev->msix_entries[i].entry = i;
+
+ vp_dev->msix_preset_vectors = 1;
+ vp_dev->msix_per_vq_vectors = max_vqs;
+ for (;;) {
+ err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries,
+ vectors);
+ /* Error out if not enough vectors */
+ if (err > 0 && err < VP_MSIX_MIN_VECTORS)
+ err = -EBUSY;
+ if (err <= 0)
+ break;
+ /* Not enough vectors for all queues. Retry, disabling
+ * per-queue interrupts */
+ vectors = VP_MSIX_MIN_VECTORS;
+ vp_dev->msix_preset_vectors = VP_MSIX_MIN_VECTORS;
+ vp_dev->msix_per_vq_vectors = 0;
+ snprintf(vp_dev->msix_names[VP_MSIX_VQ_VECTOR],
+ sizeof *vp_dev->msix_names, "%s-vq", name);
+ }
+
+ if (!err)
+ vp_dev->msix_enabled = 1;
+ if (err) {
+ /* Can't allocate enough MSI-X vectors, use regular interrupt */
+ vp_dev->msix_enabled = 0;
+ vp_dev->msix_preset_vectors = 0;
+ vp_dev->msix_per_vq_vectors = 0;
+ /* Register a handler for the queue with the PCI device's
+ * interrupt */
+ err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
+ IRQF_SHARED, name, vp_dev);
+ if (err)
+ goto error_irq;
+ vp_dev->intx_enabled = 1;
+ }
+ for (i = 0; i < vp_dev->msix_preset_vectors; ++i) {
+ err = request_irq(vp_dev->msix_entries[i].vector,
+ i == VP_MSIX_CONFIG_VECTOR ?
+ vp_config_changed : vp_vring_interrupt,
+ 0, vp_dev->msix_names[i], vp_dev);
+ if (err) {
+ /* Set msix_preset_vectors so that only vectors we
+ * already allocated will be freed by vp_free_vqs. */
+ vp_dev->msix_preset_vectors = i;
+ goto error_irq;
+ }
+
+ /* Set the vector used for configuration */
+ if (i == VP_MSIX_CONFIG_VECTOR)
+ iowrite16(VP_MSIX_CONFIG_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+ }
+ return 0;
+error_irq:
+ vp_free_vectors(vdev);
+ kfree(vp_dev->msix_names);
+error_names:
+ kfree(vp_dev->msix_entries);
+error_entries:
+ return err;
+}
+
static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
void (*callback)(struct virtqueue *vq))
{
@@ -229,7 +366,7 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
struct virtio_pci_vq_info *info;
struct virtqueue *vq;
unsigned long flags, size;
- u16 num;
+ u16 num, vector;
int err;
/* Select the queue we're interested in */
@@ -248,6 +385,7 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
info->queue_index = index;
info->num = num;
+ info->vector = VP_MSIX_NO_VECTOR;
size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
@@ -271,12 +409,29 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
vq->priv = info;
info->vq = vq;
+ /* allocate per-vq vector if available and necessary */
+ if (vp_dev->msix_per_vq_vectors && callback) {
+ vector = VP_MSIX_VQ_VECTOR + vp_dev->msix_per_vq_vectors - 1;
+ err = request_irq(vp_dev->msix_entries[vector].vector,
+ vring_interrupt, 0,
+ vp_dev->msix_names[vector], vq);
+ if (err)
+ goto out_request_irq;
+ info->vector = vector;
+ vp_dev->msix_per_vq_vectors--;
+ iowrite16(vector, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+ } else if (vp_dev->msix_enabled)
+ iowrite16(VP_MSIX_VQ_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+
spin_lock_irqsave(&vp_dev->lock, flags);
list_add(&info->node, &vp_dev->virtqueues);
spin_unlock_irqrestore(&vp_dev->lock, flags);
return vq;
+out_request_irq:
+ vring_del_virtqueue(vq);
out_activate_queue:
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
free_pages_exact(info->queue, size);
@@ -285,17 +440,27 @@ out_info:
return ERR_PTR(err);
}
-/* the config->del_vq() implementation */
static void vp_del_vq(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
struct virtio_pci_vq_info *info = vq->priv;
unsigned long size;
+ iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
+
+ if (info->vector != VP_MSIX_NO_VECTOR)
+ free_irq(vp_dev->msix_entries[info->vector].vector, vq);
+
+ if (vp_dev->msix_enabled) {
+ iowrite16(VP_MSIX_NO_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+ /* Flush the write out to device */
+ ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
+ }
+
vring_del_virtqueue(vq);
/* Select and deactivate the queue */
- iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN));
@@ -303,6 +468,7 @@ static void vp_del_vq(struct virtqueue *vq)
kfree(info);
}
+/* the config->del_vqs() implementation */
static void vp_del_vqs(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -316,23 +482,38 @@ static void vp_del_vqs(struct virtio_device *vdev)
list_for_each_entry(info, &virtqueues, node)
vp_del_vq(info->vq);
+
+ vp_free_vectors(vdev);
}
+/* the config->find_vqs() implementation */
static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct virtqueue *vqs[],
virtqueue_callback *callbacks[])
{
- int i;
+ int vectors = 0;
+ int i, err;
+
+ /* How many vectors would we like? */
+ for (i = 0; i < nvqs; ++i)
+ if (callbacks[i])
+ ++vectors;
+
+ err = vp_request_vectors(vdev, vectors);
+ if (err)
+ goto error_request;
for (i = 0; i < nvqs; ++i) {
vqs[i] = vp_find_vq(vdev, i, callbacks[i]);
if (IS_ERR(vqs[i]))
- goto error;
+ goto error_find;
}
return 0;
-error:
+error_find:
vp_del_vqs(vdev);
+
+error_request:
return PTR_ERR(vqs[i]);
}
@@ -354,7 +535,7 @@ static void virtio_pci_release_dev(struct device *_d)
struct virtio_pci_device *vp_dev = to_vp_device(dev);
struct pci_dev *pci_dev = vp_dev->pci_dev;
- free_irq(pci_dev->irq, vp_dev);
+ vp_del_vqs(dev);
pci_set_drvdata(pci_dev, NULL);
pci_iounmap(pci_dev, vp_dev->ioaddr);
pci_release_regions(pci_dev);
@@ -413,21 +594,13 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
vp_dev->vdev.id.device = pci_dev->subsystem_device;
- /* register a handler for the queue with the PCI device's interrupt */
- err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
- dev_name(&vp_dev->vdev.dev), vp_dev);
- if (err)
- goto out_set_drvdata;
-
/* finally register the virtio device */
err = register_virtio_device(&vp_dev->vdev);
if (err)
- goto out_req_irq;
+ goto out_set_drvdata;
return 0;
-out_req_irq:
- free_irq(pci_dev->irq, vp_dev);
out_set_drvdata:
pci_set_drvdata(pci_dev, NULL);
pci_iounmap(pci_dev, vp_dev->ioaddr);
diff --git a/include/linux/virtio_pci.h b/include/linux/virtio_pci.h
index cd0fd5d..4a0275b 100644
--- a/include/linux/virtio_pci.h
+++ b/include/linux/virtio_pci.h
@@ -47,9 +47,15 @@
/* The bit of the ISR which indicates a device configuration change. */
#define VIRTIO_PCI_ISR_CONFIG 0x2
+/* MSI-X registers: only enabled if MSI-X is enabled. */
+/* A 16-bit vector for configuration changes. */
+#define VIRTIO_MSI_CONFIG_VECTOR 20
+/* A 16-bit vector for selected queue notifications. */
+#define VIRTIO_MSI_QUEUE_VECTOR 22
+
/* The remaining space is defined by each driver as the per-driver
* configuration space */
-#define VIRTIO_PCI_CONFIG 20
+#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20)
/* Virtio ABI version, this must match exactly */
#define VIRTIO_PCI_ABI_VERSION 0
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 22+ messages in thread