* [PATCHv5 1/3] virtio: find_vqs/del_vqs virtio operations
[not found] <cover.1242241196.git.mst@redhat.com>
@ 2009-05-13 19:08 ` Michael S. Tsirkin
2009-05-14 6:35 ` Christian Borntraeger
2009-05-13 19:09 ` [PATCHv5 2/3] virtio_pci: split up vp_interrupt Michael S. Tsirkin
2009-05-13 19:11 ` [PATCHv5 3/3] virtio_pci: optional MSI-X support Michael S. Tsirkin
2 siblings, 1 reply; 5+ messages in thread
From: Michael S. Tsirkin @ 2009-05-13 19:08 UTC (permalink / raw)
To: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte <
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 | 6 ++--
drivers/char/hw_random/virtio-rng.c | 6 ++--
drivers/char/virtio_console.c | 26 ++++++++-----------
drivers/lguest/lguest_device.c | 36 +++++++++++++++++++++++++-
drivers/net/virtio_net.c | 45 +++++++++++++--------------------
drivers/s390/kvm/kvm_virtio.c | 36 +++++++++++++++++++++++++-
drivers/virtio/virtio_balloon.c | 27 ++++++++------------
drivers/virtio/virtio_pci.c | 37 ++++++++++++++++++++++-----
include/linux/virtio_config.h | 46 ++++++++++++++++++++++++++--------
net/9p/trans_virtio.c | 2 +-
10 files changed, 180 insertions(+), 87 deletions(-)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 8f7c956..c9f5627 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -224,7 +224,7 @@ 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, "requests");
+ vblk->vq = virtio_find_single_vq(vdev, blk_done, "requests");
if (IS_ERR(vblk->vq)) {
err = PTR_ERR(vblk->vq);
goto out_free_vblk;
@@ -323,7 +323,7 @@ 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 +344,7 @@ 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 2aeafce..f2041fe 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -94,13 +94,13 @@ static int virtrng_probe(struct virtio_device *vdev)
int err;
/* We expect a single virtqueue. */
- vq = vdev->config->find_vq(vdev, 0, random_recv_done, "input");
+ vq = virtio_find_single_vq(vdev, random_recv_done, "input");
if (IS_ERR(vq))
return PTR_ERR(vq);
err = hwrng_register(&virtio_hwrng);
if (err) {
- vdev->config->del_vq(vq);
+ vdev->config->del_vqs(vdev);
return err;
}
@@ -112,7 +112,7 @@ 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 58684e4..c74dacf 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -188,6 +188,9 @@ 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)
{
+ vq_callback_t *callbacks[] = { hvc_handle_input, NULL};
+ const char *names[] = { "input", "output" };
+ struct virtqueue *vqs[2];
int err;
vdev = dev;
@@ -199,20 +202,15 @@ 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, "input");
- if (IS_ERR(in_vq)) {
- err = PTR_ERR(in_vq);
+ err = vdev->config->find_vqs(vdev, 2, vqs, callbacks, names);
+ if (err)
goto free;
- }
- out_vq = vdev->config->find_vq(vdev, 1, NULL, "output");
- 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 +231,15 @@ 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 4babed8..f8e0c8b 100644
--- a/drivers/lguest/lguest_device.c
+++ b/drivers/lguest/lguest_device.c
@@ -313,6 +313,38 @@ static void lg_del_vq(struct virtqueue *vq)
kfree(lvq);
}
+static void lg_del_vqs(struct virtio_device *vdev)
+{
+ struct virtqueue *vq, *n;
+
+ list_for_each_entry_safe(vq, n, &vdev->vqs, list)
+ kvm_del_vq(vq);
+}
+
+static int lg_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[]
+ vq_callback_t *callbacks[],
+ const char *names[])
+{
+ 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);
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = lg_find_vq(vdev, i, callbacks[i], names[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ }
+ 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,
@@ -322,8 +354,8 @@ 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 be3b734..7fa620d 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -845,6 +845,10 @@ static int virtnet_probe(struct virtio_device *vdev)
int err;
struct net_device *dev;
struct virtnet_info *vi;
+ struct virtqueue *vqs[3];
+ vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
+ const char *names[] = { "input", "output", "control" };
+ int nvqs;
/* Allocate ourselves a network device with room for our info */
dev = alloc_etherdev(sizeof(struct virtnet_info));
@@ -905,25 +909,19 @@ 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, "input");
- if (IS_ERR(vi->rvq)) {
- err = PTR_ERR(vi->rvq);
+ /* We expect two virtqueues, receive then send,
+ * and optionally control. */
+ nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
+
+ err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
+ if (err)
goto free;
- }
- vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done, "output");
- 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, "control");
- 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 +939,7 @@ 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 +960,8 @@ 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 +987,10 @@ 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 ba8995f..e719188 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -227,6 +227,38 @@ static void kvm_del_vq(struct virtqueue *vq)
KVM_S390_VIRTIO_RING_ALIGN));
}
+static void vp_del_vqs(struct virtio_device *vdev)
+{
+ struct virtqueue *vq, *n;
+
+ list_for_each_entry_safe(vq, n, &vdev->vqs, list)
+ kvm_del_vq(vq);
+}
+
+static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ vq_callback_t *callbacks[],
+ const char *names[])
+{
+ struct kvm_device *kdev = to_kvmdev(vdev);
+ int i;
+
+ /* We must have this many virtqueues. */
+ if (nvqs > kdev->desc->num_vq)
+ return -ENOENT;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = kvm_find_vq(vdev, i, callbacks[i], names[i]);
+ if (IS_ERR(vqs[i]))
+ goto error;
+ }
+ return 0;
+
+error:
+ kvm_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+}
+
/*
* The config ops structure as defined by virtio config
*/
@@ -238,8 +270,8 @@ 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 0fa73b4..26b2782 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -204,6 +204,9 @@ static int balloon(void *_vballoon)
static int virtballoon_probe(struct virtio_device *vdev)
{
struct virtio_balloon *vb;
+ struct virtqueue *vqs[2];
+ vq_callback_t *callbacks[] = { balloon_ack, balloon_ack };
+ const char *names[] = { "inflate", "deflate" };
int err;
vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
@@ -218,22 +221,17 @@ 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, "inflate");
- if (IS_ERR(vb->inflate_vq)) {
- err = PTR_ERR(vb->inflate_vq);
+ err = vdev->config->find_vqs(vdev, 2, vqs, callbacks, names);
+ if (err)
goto out_free_vb;
- }
- vb->deflate_vq = vdev->config->find_vq(vdev, 1, balloon_ack, "deflate");
- 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 +239,8 @@ 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 +260,7 @@ 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 be4047a..027f13f 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -276,11 +276,7 @@ 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);
@@ -293,14 +289,41 @@ static void vp_del_vq(struct virtqueue *vq)
kfree(info);
}
+static void vp_del_vqs(struct virtio_device *vdev)
+{
+ struct virtqueue *vq, *n;
+
+ list_for_each_entry_safe(vq, n, &vdev->vqs, list)
+ vp_del_vq(vq);
+}
+
+static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ vq_callback_t *callbacks[],
+ const char *names[])
+{
+ int i;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = vp_find_vq(vdev, i, callbacks[i], names[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 9fae274..4938050 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -49,16 +49,26 @@
* @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 virtqueue callback
- * name: the virtqueue name (mainly for debugging)
- * 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
+ * names: array of virtqueue names (mainly for debugging)
+ * 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).
@@ -67,6 +77,7 @@
* This gives the final feature bits for the device: it can change
* the dev->feature bits if it wants.
*/
+typedef void vq_callback_t(struct virtqueue *);
struct virtio_config_ops
{
void (*get)(struct virtio_device *vdev, unsigned offset,
@@ -76,11 +87,11 @@ 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 *),
- const char *name);
- void (*del_vq)(struct virtqueue *vq);
+ int (*find_vqs)(struct virtio_device *, unsigned nvqs,
+ struct virtqueue *vqs[],
+ vq_callback_t *callbacks[],
+ const char *names[]);
+ void (*del_vqs)(struct virtio_device *);
u32 (*get_features)(struct virtio_device *vdev);
void (*finalize_features)(struct virtio_device *vdev);
};
@@ -128,5 +139,18 @@ static inline int virtio_config_buf(struct virtio_device *vdev,
vdev->config->get(vdev, offset, buf, len);
return 0;
}
+
+static inline
+struct virtqueue *virtio_find_single_vq(struct virtio_device *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;
+}
#endif /* __KERNEL__ */
#endif /* _LINUX_VIRTIO_CONFIG_H */
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index ab8791f..977a8c3 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -246,7 +246,7 @@ 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, "requests");
+ chan->vq = virtio_find_single_vq(vdev, req_done, "requests");
if (IS_ERR(chan->vq)) {
err = PTR_ERR(chan->vq);
goto out_free_vq;
--
1.6.3.rc3.1.g830204
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCHv5 3/3] virtio_pci: optional MSI-X support
[not found] <cover.1242241196.git.mst@redhat.com>
2009-05-13 19:08 ` [PATCHv5 1/3] virtio: find_vqs/del_vqs virtio operations Michael S. Tsirkin
2009-05-13 19:09 ` [PATCHv5 2/3] virtio_pci: split up vp_interrupt Michael S. Tsirkin
@ 2009-05-13 19:11 ` Michael S. Tsirkin
2009-05-14 2:16 ` Anthony Liguori
2 siblings, 1 reply; 5+ messages in thread
From: Michael S. Tsirkin @ 2009-05-13 19:11 UTC (permalink / raw)
To: Christian Borntraeger, virtualization, Anthony Liguori, kvm, avi,
Carsten Otte <
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 | 227 +++++++++++++++++++++++++++++++++++++++----
include/linux/virtio_pci.h | 10 ++-
2 files changed, 217 insertions(+), 20 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 951e673..65627a4 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -42,6 +42,26 @@ 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 available vectors */
+ unsigned msix_vectors;
+ /* Vectors allocated */
+ unsigned msix_used_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,
};
struct virtio_pci_vq_info
@@ -60,6 +80,9 @@ 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 +132,8 @@ 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 +147,8 @@ 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 +246,121 @@ 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_used_vectors; ++i)
+ free_irq(vp_dev->msix_entries[i].vector, vp_dev);
+ vp_dev->msix_used_vectors = 0;
+
+ if (vp_dev->msix_enabled) {
+ /* Disable the vector used for configuration */
+ iowrite16(VIRTIO_MSI_NO_VECTOR,
+ vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+ /* Flush the write out to device */
+ ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+
+ vp_dev->msix_enabled = 0;
+ pci_disable_msix(vp_dev->pci_dev);
+ }
+}
+
+static int vp_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
+ int *options, int noptions)
+{
+ int i;
+ for (i = 0; i < noptions; ++i)
+ if (!pci_enable_msix(dev, entries, options[i]))
+ return options[i];
+ return -EBUSY;
+}
+
+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, v;
+ int err = -ENOMEM;
+ /* We want at most one vector per queue and one for config changes.
+ * Fallback to separate vectors for config and a shared for queues.
+ * Finally fall back to regular interrupts. */
+ int options[] = { max_vqs + 1, 2 };
+ int nvectors = max(options[0], options[1]);
+
+ vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
+ GFP_KERNEL);
+ if (!vp_dev->msix_entries)
+ goto error_entries;
+ vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
+ GFP_KERNEL);
+ if (!vp_dev->msix_names)
+ goto error_names;
+
+ for (i = 0; i < nvectors; ++i)
+ vp_dev->msix_entries[i].entry = i;
+
+ err = vp_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries,
+ options, ARRAY_SIZE(options));
+ if (err < 0) {
+ /* Can't allocate enough MSI-X vectors, use regular interrupt */
+ vp_dev->msix_vectors = 0;
+ 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;
+ } else {
+ vp_dev->msix_vectors = err;
+ vp_dev->msix_enabled = 1;
+
+ /* Set the vector used for configuration */
+ v = vp_dev->msix_used_vectors;
+ snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
+ "%s-config", name);
+ err = request_irq(vp_dev->msix_entries[v].vector,
+ vp_config_changed, 0, vp_dev->msix_names[v],
+ vp_dev);
+ if (err)
+ goto error_irq;
+ ++vp_dev->msix_used_vectors;
+
+ iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+ /* Verify we had enough resources to assign the vector */
+ v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
+ if (v == VIRTIO_MSI_NO_VECTOR) {
+ err = -EBUSY;
+ goto error_irq;
+ }
+ }
+
+ if (vp_dev->msix_vectors && vp_dev->msix_vectors != max_vqs + 1) {
+ /* Shared vector for all VQs */
+ v = vp_dev->msix_used_vectors;
+ snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
+ "%s-virtqueues", name);
+ err = request_irq(vp_dev->msix_entries[v].vector,
+ vp_vring_interrupt, 0, vp_dev->msix_names[v],
+ vp_dev);
+ if (err)
+ goto error_irq;
+ ++vp_dev->msix_used_vectors;
+ }
+ 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),
const char *name)
@@ -230,7 +369,7 @@ 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 */
@@ -249,6 +388,7 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
info->queue_index = index;
info->num = num;
+ info->vector = VIRTIO_MSI_NO_VECTOR;
size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
@@ -272,12 +412,43 @@ 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 (callback && vp_dev->msix_used_vectors < vp_dev->msix_vectors) {
+ vector = vp_dev->msix_used_vectors;
+ snprintf(vp_dev->msix_names[vector], sizeof *vp_dev->msix_names,
+ "%s-%s", dev_name(&vp_dev->vdev.dev), name);
+ 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_used_vectors;
+ } else
+ vector = VP_MSIX_VQ_VECTOR;
+
+ if (callback && vp_dev->msix_enabled) {
+ iowrite16(vector, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+ vector = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
+ if (vector == VIRTIO_MSI_NO_VECTOR) {
+ err = -EBUSY;
+ goto out_assign;
+ }
+ }
+
spin_lock_irqsave(&vp_dev->lock, flags);
list_add(&info->node, &vp_dev->virtqueues);
spin_unlock_irqrestore(&vp_dev->lock, flags);
return vq;
+out_assign:
+ if (info->vector != VIRTIO_MSI_NO_VECTOR) {
+ free_irq(vp_dev->msix_entries[info->vector].vector, vq);
+ --vp_dev->msix_used_vectors;
+ }
+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);
@@ -286,17 +457,27 @@ 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 != VIRTIO_MSI_NO_VECTOR)
+ free_irq(vp_dev->msix_entries[info->vector].vector, vq);
+
+ if (vp_dev->msix_enabled) {
+ iowrite16(VIRTIO_MSI_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));
@@ -304,30 +485,46 @@ 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 virtqueue *vq, *n;
list_for_each_entry_safe(vq, n, &vdev->vqs, list)
vp_del_vq(vq);
+
+ vp_free_vectors(vdev);
}
+/* the config->find_vqs() implementation */
static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char *names[])
{
- 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], names[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]);
}
@@ -349,7 +546,7 @@ 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);
@@ -408,21 +605,13 @@ 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..9a3d7c4 100644
--- a/include/linux/virtio_pci.h
+++ b/include/linux/virtio_pci.h
@@ -47,9 +47,17 @@
/* 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
+/* Vector value used to disable MSI for queue */
+#define VIRTIO_MSI_NO_VECTOR 0xffff
+
/* 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
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