summaryrefslogtreecommitdiffstats
path: root/virt/kvm/arm/vgic/vgic-its.c
diff options
context:
space:
mode:
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-its.c')
-rw-r--r--virt/kvm/arm/vgic/vgic-its.c158
1 files changed, 114 insertions, 44 deletions
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 07411cf967b9..4660a7d04eea 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -51,7 +51,7 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid)
irq = kzalloc(sizeof(struct vgic_irq), GFP_KERNEL);
if (!irq)
- return NULL;
+ return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&irq->lpi_list);
INIT_LIST_HEAD(&irq->ap_list);
@@ -441,39 +441,63 @@ static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm,
* Find the target VCPU and the LPI number for a given devid/eventid pair
* and make this IRQ pending, possibly injecting it.
* Must be called with the its_lock mutex held.
+ * Returns 0 on success, a positive error value for any ITS mapping
+ * related errors and negative error values for generic errors.
*/
-static void vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
- u32 devid, u32 eventid)
+static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
+ u32 devid, u32 eventid)
{
+ struct kvm_vcpu *vcpu;
struct its_itte *itte;
if (!its->enabled)
- return;
+ return -EBUSY;
itte = find_itte(its, devid, eventid);
- /* Triggering an unmapped IRQ gets silently dropped. */
- if (itte && its_is_collection_mapped(itte->collection)) {
- struct kvm_vcpu *vcpu;
-
- vcpu = kvm_get_vcpu(kvm, itte->collection->target_addr);
- if (vcpu && vcpu->arch.vgic_cpu.lpis_enabled) {
- spin_lock(&itte->irq->irq_lock);
- itte->irq->pending = true;
- vgic_queue_irq_unlock(kvm, itte->irq);
- }
- }
+ if (!itte || !its_is_collection_mapped(itte->collection))
+ return E_ITS_INT_UNMAPPED_INTERRUPT;
+
+ vcpu = kvm_get_vcpu(kvm, itte->collection->target_addr);
+ if (!vcpu)
+ return E_ITS_INT_UNMAPPED_INTERRUPT;
+
+ if (!vcpu->arch.vgic_cpu.lpis_enabled)
+ return -EBUSY;
+
+ spin_lock(&itte->irq->irq_lock);
+ itte->irq->pending = true;
+ vgic_queue_irq_unlock(kvm, itte->irq);
+
+ return 0;
+}
+
+static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev)
+{
+ struct vgic_io_device *iodev;
+
+ if (dev->ops != &kvm_io_gic_ops)
+ return NULL;
+
+ iodev = container_of(dev, struct vgic_io_device, dev);
+
+ if (iodev->iodev_type != IODEV_ITS)
+ return NULL;
+
+ return iodev;
}
/*
* Queries the KVM IO bus framework to get the ITS pointer from the given
* doorbell address.
* We then call vgic_its_trigger_msi() with the decoded data.
+ * According to the KVM_SIGNAL_MSI API description returns 1 on success.
*/
int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
{
u64 address;
struct kvm_io_device *kvm_io_dev;
struct vgic_io_device *iodev;
+ int ret;
if (!vgic_has_its(kvm))
return -ENODEV;
@@ -485,15 +509,28 @@ int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address);
if (!kvm_io_dev)
- return -ENODEV;
+ return -EINVAL;
- iodev = container_of(kvm_io_dev, struct vgic_io_device, dev);
+ iodev = vgic_get_its_iodev(kvm_io_dev);
+ if (!iodev)
+ return -EINVAL;
mutex_lock(&iodev->its->its_lock);
- vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data);
+ ret = vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data);
mutex_unlock(&iodev->its->its_lock);
- return 0;
+ if (ret < 0)
+ return ret;
+
+ /*
+ * KVM_SIGNAL_MSI demands a return value > 0 for success and 0
+ * if the guest has blocked the MSI. So we map any LPI mapping
+ * related error to that.
+ */
+ if (ret)
+ return 0;
+ else
+ return 1;
}
/* Requires the its_lock to be held. */
@@ -502,7 +539,8 @@ static void its_free_itte(struct kvm *kvm, struct its_itte *itte)
list_del(&itte->itte_list);
/* This put matches the get in vgic_add_lpi. */
- vgic_put_irq(kvm, itte->irq);
+ if (itte->irq)
+ vgic_put_irq(kvm, itte->irq);
kfree(itte);
}
@@ -697,6 +735,7 @@ static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
struct its_device *device;
struct its_collection *collection, *new_coll = NULL;
int lpi_nr;
+ struct vgic_irq *irq;
device = find_its_device(its, device_id);
if (!device)
@@ -710,6 +749,10 @@ static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
lpi_nr >= max_lpis_propbaser(kvm->arch.vgic.propbaser))
return E_ITS_MAPTI_PHYSICALID_OOR;
+ /* If there is an existing mapping, behavior is UNPREDICTABLE. */
+ if (find_itte(its, device_id, event_id))
+ return 0;
+
collection = find_collection(its, coll_id);
if (!collection) {
int ret = vgic_its_alloc_collection(its, &collection, coll_id);
@@ -718,22 +761,28 @@ static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
new_coll = collection;
}
- itte = find_itte(its, device_id, event_id);
+ itte = kzalloc(sizeof(struct its_itte), GFP_KERNEL);
if (!itte) {
- itte = kzalloc(sizeof(struct its_itte), GFP_KERNEL);
- if (!itte) {
- if (new_coll)
- vgic_its_free_collection(its, coll_id);
- return -ENOMEM;
- }
-
- itte->event_id = event_id;
- list_add_tail(&itte->itte_list, &device->itt_head);
+ if (new_coll)
+ vgic_its_free_collection(its, coll_id);
+ return -ENOMEM;
}
+ itte->event_id = event_id;
+ list_add_tail(&itte->itte_list, &device->itt_head);
+
itte->collection = collection;
itte->lpi = lpi_nr;
- itte->irq = vgic_add_lpi(kvm, lpi_nr);
+
+ irq = vgic_add_lpi(kvm, lpi_nr);
+ if (IS_ERR(irq)) {
+ if (new_coll)
+ vgic_its_free_collection(its, coll_id);
+ its_free_itte(kvm, itte);
+ return PTR_ERR(irq);
+ }
+ itte->irq = irq;
+
update_affinity_itte(kvm, itte);
/*
@@ -981,9 +1030,7 @@ static int vgic_its_cmd_handle_int(struct kvm *kvm, struct vgic_its *its,
u32 msi_data = its_cmd_get_id(its_cmd);
u64 msi_devid = its_cmd_get_deviceid(its_cmd);
- vgic_its_trigger_msi(kvm, its, msi_devid, msi_data);
-
- return 0;
+ return vgic_its_trigger_msi(kvm, its, msi_devid, msi_data);
}
/*
@@ -1288,13 +1335,13 @@ void vgic_enable_lpis(struct kvm_vcpu *vcpu)
its_sync_lpi_pending_table(vcpu);
}
-static int vgic_its_init_its(struct kvm *kvm, struct vgic_its *its)
+static int vgic_register_its_iodev(struct kvm *kvm, struct vgic_its *its)
{
struct vgic_io_device *iodev = &its->iodev;
int ret;
- if (its->initialized)
- return 0;
+ if (!its->initialized)
+ return -EBUSY;
if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base))
return -ENXIO;
@@ -1311,9 +1358,6 @@ static int vgic_its_init_its(struct kvm *kvm, struct vgic_its *its)
KVM_VGIC_V3_ITS_SIZE, &iodev->dev);
mutex_unlock(&kvm->slots_lock);
- if (!ret)
- its->initialized = true;
-
return ret;
}
@@ -1435,9 +1479,6 @@ static int vgic_its_set_attr(struct kvm_device *dev,
if (type != KVM_VGIC_ITS_ADDR_TYPE)
return -ENODEV;
- if (its->initialized)
- return -EBUSY;
-
if (copy_from_user(&addr, uaddr, sizeof(addr)))
return -EFAULT;
@@ -1453,7 +1494,9 @@ static int vgic_its_set_attr(struct kvm_device *dev,
case KVM_DEV_ARM_VGIC_GRP_CTRL:
switch (attr->attr) {
case KVM_DEV_ARM_VGIC_CTRL_INIT:
- return vgic_its_init_its(dev->kvm, its);
+ its->initialized = true;
+
+ return 0;
}
break;
}
@@ -1498,3 +1541,30 @@ int kvm_vgic_register_its_device(void)
return kvm_register_device_ops(&kvm_arm_vgic_its_ops,
KVM_DEV_TYPE_ARM_VGIC_ITS);
}
+
+/*
+ * Registers all ITSes with the kvm_io_bus framework.
+ * To follow the existing VGIC initialization sequence, this has to be
+ * done as late as possible, just before the first VCPU runs.
+ */
+int vgic_register_its_iodevs(struct kvm *kvm)
+{
+ struct kvm_device *dev;
+ int ret = 0;
+
+ list_for_each_entry(dev, &kvm->devices, vm_node) {
+ if (dev->ops != &kvm_arm_vgic_its_ops)
+ continue;
+
+ ret = vgic_register_its_iodev(kvm, dev->private);
+ if (ret)
+ return ret;
+ /*
+ * We don't need to care about tearing down previously
+ * registered ITSes, as the kvm_io_bus framework removes
+ * them for us if the VM gets destroyed.
+ */
+ }
+
+ return ret;
+}