diff options
Diffstat (limited to 'drivers/virtio')
| -rw-r--r-- | drivers/virtio/virtio.c | 46 | ||||
| -rw-r--r-- | drivers/virtio/virtio_balloon.c | 12 | ||||
| -rw-r--r-- | drivers/virtio/virtio_pci.c | 41 | ||||
| -rw-r--r-- | drivers/virtio/virtio_ring.c | 13 |
4 files changed, 73 insertions, 39 deletions
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index b535483..7084e7e 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -2,6 +2,9 @@ #include <linux/spinlock.h> #include <linux/virtio_config.h> +/* Unique numbering for virtio devices. */ +static unsigned int dev_index; + static ssize_t device_show(struct device *_d, struct device_attribute *attr, char *buf) { @@ -80,19 +83,51 @@ static void add_status(struct virtio_device *dev, unsigned status) dev->config->set_status(dev, dev->config->get_status(dev) | status); } +void virtio_check_driver_offered_feature(const struct virtio_device *vdev, + unsigned int fbit) +{ + unsigned int i; + struct virtio_driver *drv = container_of(vdev->dev.driver, + struct virtio_driver, driver); + + for (i = 0; i < drv->feature_table_size; i++) + if (drv->feature_table[i] == fbit) + return; + BUG(); +} +EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature); + static int virtio_dev_probe(struct device *_d) { - int err; + int err, i; struct virtio_device *dev = container_of(_d,struct virtio_device,dev); struct virtio_driver *drv = container_of(dev->dev.driver, struct virtio_driver, driver); + u32 device_features; + /* We have a driver! */ add_status(dev, VIRTIO_CONFIG_S_DRIVER); + + /* Figure out what features the device supports. */ + device_features = dev->config->get_features(dev); + + /* Features supported by both device and driver into dev->features. */ + memset(dev->features, 0, sizeof(dev->features)); + for (i = 0; i < drv->feature_table_size; i++) { + unsigned int f = drv->feature_table[i]; + BUG_ON(f >= 32); + if (device_features & (1 << f)) + set_bit(f, dev->features); + } + err = drv->probe(dev); if (err) add_status(dev, VIRTIO_CONFIG_S_FAILED); - else + else { + /* They should never have set feature bits beyond 32 */ + dev->config->set_features(dev, dev->features[0]); add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK); + } return err; } @@ -114,6 +149,8 @@ static int virtio_dev_remove(struct device *_d) int register_virtio_driver(struct virtio_driver *driver) { + /* Catch this early. */ + BUG_ON(driver->feature_table_size && !driver->feature_table); driver->driver.bus = &virtio_bus; driver->driver.probe = virtio_dev_probe; driver->driver.remove = virtio_dev_remove; @@ -132,7 +169,10 @@ int register_virtio_device(struct virtio_device *dev) int err; dev->dev.bus = &virtio_bus; - sprintf(dev->dev.bus_id, "%u", dev->index); + + /* Assign a unique device index and hence name. */ + dev->index = dev_index++; + sprintf(dev->dev.bus_id, "virtio%u", dev->index); /* We always start by resetting the device, in case a previous * driver messed it up. This also tests that code path a little. */ diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 0b3efc3..bfef604 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -155,9 +155,9 @@ static void virtballoon_changed(struct virtio_device *vdev) static inline s64 towards_target(struct virtio_balloon *vb) { u32 v; - __virtio_config_val(vb->vdev, - offsetof(struct virtio_balloon_config, num_pages), - &v); + vb->vdev->config->get(vb->vdev, + offsetof(struct virtio_balloon_config, num_pages), + &v, sizeof(v)); return v - vb->num_pages; } @@ -227,7 +227,7 @@ static int virtballoon_probe(struct virtio_device *vdev) } vb->tell_host_first - = vdev->config->feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST); + = virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST); return 0; @@ -259,7 +259,11 @@ static void virtballoon_remove(struct virtio_device *vdev) kfree(vb); } +static unsigned int features[] = { VIRTIO_BALLOON_F_MUST_TELL_HOST }; + static struct virtio_driver virtio_balloon = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, .driver.owner = THIS_MODULE, .id_table = id_table, diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index c0df924..eae72363 100644 --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -78,32 +78,28 @@ static struct device virtio_pci_root = { .bus_id = "virtio-pci", }; -/* Unique numbering for devices under the kvm root */ -static unsigned int dev_index; - /* Convert a generic virtio device to our structure */ static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) { return container_of(vdev, struct virtio_pci_device, vdev); } -/* virtio config->feature() implementation */ -static bool vp_feature(struct virtio_device *vdev, unsigned bit) +/* virtio config->get_features() implementation */ +static u32 vp_get_features(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); - u32 mask; - - /* Since this function is supposed to have the side effect of - * enabling a queried feature, we simulate that by doing a read - * from the host feature bitmask and then writing to the guest - * feature bitmask */ - mask = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); - if (mask & (1 << bit)) { - mask |= (1 << bit); - iowrite32(mask, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); - } - return !!(mask & (1 << bit)); + /* When someone needs more than 32 feature bits, we'll need to + * steal a bit to indicate that the rest are somewhere else. */ + return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); +} + +/* virtio config->set_features() implementation */ +static void vp_set_features(struct virtio_device *vdev, u32 features) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + iowrite32(features, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); } /* virtio config->get() implementation */ @@ -145,14 +141,14 @@ static void vp_set_status(struct virtio_device *vdev, u8 status) struct virtio_pci_device *vp_dev = to_vp_device(vdev); /* We should never be setting status to 0. */ BUG_ON(status == 0); - return iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS); + iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS); } static void vp_reset(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); /* 0 status means a reset. */ - return iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS); + iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS); } /* the notify function used when creating a virt queue */ @@ -293,7 +289,6 @@ static void vp_del_vq(struct virtqueue *vq) } static struct virtio_config_ops virtio_pci_config_ops = { - .feature = vp_feature, .get = vp_get, .set = vp_set, .get_status = vp_get_status, @@ -301,6 +296,8 @@ static struct virtio_config_ops virtio_pci_config_ops = { .reset = vp_reset, .find_vq = vp_find_vq, .del_vq = vp_del_vq, + .get_features = vp_get_features, + .set_features = vp_set_features, }; /* the PCI probing function */ @@ -325,10 +322,6 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev, if (vp_dev == NULL) return -ENOMEM; - snprintf(vp_dev->vdev.dev.bus_id, BUS_ID_SIZE, "virtio%d", dev_index); - vp_dev->vdev.index = dev_index; - dev_index++; - vp_dev->vdev.dev.parent = &virtio_pci_root; vp_dev->vdev.config = &virtio_pci_config_ops; vp_dev->pci_dev = pci_dev; diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index c2fa5c6..72bf8bc 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -184,6 +184,11 @@ static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len) START_USE(vq); + if (unlikely(vq->broken)) { + END_USE(vq); + return NULL; + } + if (!more_used(vq)) { pr_debug("No more buffers in queue\n"); END_USE(vq); @@ -222,7 +227,6 @@ static bool vring_enable_cb(struct virtqueue *_vq) struct vring_virtqueue *vq = to_vvq(_vq); START_USE(vq); - BUG_ON(!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)); /* We optimistically turn back on interrupts, then check if there was * more to do. */ @@ -249,13 +253,6 @@ irqreturn_t vring_interrupt(int irq, void *_vq) if (unlikely(vq->broken)) return IRQ_HANDLED; - /* Other side may have missed us turning off the interrupt, - * but we should preserve disable semantic for virtio users. */ - if (unlikely(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) { - pr_debug("virtqueue interrupt after disable for %p\n", vq); - return IRQ_HANDLED; - } - pr_debug("virtqueue callback for %p (%p)\n", vq, vq->vq.callback); if (vq->vq.callback) vq->vq.callback(&vq->vq); |