From 0a920356748df4fb06e86c21c23d2ed6d31d37ad Mon Sep 17 00:00:00 2001
From: Weidong Han <weidong.han@intel.com>
Date: Tue, 2 Dec 2008 21:24:23 +0800
Subject: [PATCH] KVM: support device deassignment
Support device deassignment, it can be used in device hotplug.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
include/linux/kvm_host.h | 8 ++++++++
virt/kvm/kvm_main.c | 42 ++++++++++++++++++++++++++++++++++++++++
virt/kvm/vtd.c | 24 +++++++++++++++++++++++
3 files changed, 74 insertions(+)
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index c96739b4b7a31..ce5d1c17ce26f 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -334,6 +334,8 @@ int kvm_iommu_map_guest(struct kvm *kvm);
int kvm_iommu_unmap_guest(struct kvm *kvm);
int kvm_assign_device(struct kvm *kvm,
struct kvm_assigned_dev_kernel *assigned_dev);
+int kvm_deassign_device(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev);
#else /* CONFIG_DMAR */
static inline int kvm_iommu_map_pages(struct kvm *kvm,
gfn_t base_gfn,
@@ -357,6 +359,12 @@ static inline int kvm_assign_device(struct kvm *kvm,
{
return 0;
}
+
+static inline int kvm_deassign_device(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ return 0;
+}
#endif /* CONFIG_DMAR */
static inline void kvm_guest_enter(void)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c92b63462b797..3238e08e4651b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -530,6 +530,35 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
}
#endif
+#ifdef KVM_CAP_DEVICE_DEASSIGNMENT
+static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
+ struct kvm_assigned_pci_dev *assigned_dev)
+{
+ int r = 0;
+ struct kvm_assigned_dev_kernel *match;
+
+ mutex_lock(&kvm->lock);
+
+ match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
+ assigned_dev->assigned_dev_id);
+ if (!match) {
+ printk(KERN_INFO "%s: device hasn't been assigned before, "
+ "so cannot be deassigned\n", __func__);
+ r = -EINVAL;
+ goto out;
+ }
+
+ if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU)
+ kvm_deassign_device(kvm, match);
+
+ kvm_free_assigned_device(kvm, match);
+
+out:
+ mutex_unlock(&kvm->lock);
+ return r;
+}
+#endif
+
static inline int valid_vcpu(int n)
{
return likely(n >= 0 && n < KVM_MAX_VCPUS);
@@ -1862,6 +1891,19 @@ static long kvm_vm_ioctl(struct file *filp,
goto out;
break;
}
+#endif
+#ifdef KVM_CAP_DEVICE_DEASSIGNMENT
+ case KVM_DEASSIGN_PCI_DEVICE: {
+ struct kvm_assigned_pci_dev assigned_dev;
+
+ r = -EFAULT;
+ if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
+ goto out;
+ r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
+ if (r)
+ goto out;
+ break;
+ }
#endif
default:
r = kvm_arch_vm_ioctl(filp, ioctl, arg);
diff --git a/virt/kvm/vtd.c b/virt/kvm/vtd.c
index 44bb58a395a56..174ea1f8cee5f 100644
--- a/virt/kvm/vtd.c
+++ b/virt/kvm/vtd.c
@@ -116,6 +116,30 @@ int kvm_assign_device(struct kvm *kvm,
return 0;
}
+int kvm_deassign_device(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ struct dmar_domain *domain = kvm->arch.intel_iommu_domain;
+ struct pci_dev *pdev = NULL;
+
+ /* check if iommu exists and in use */
+ if (!domain)
+ return 0;
+
+ pdev = assigned_dev->dev;
+ if (pdev == NULL)
+ return -ENODEV;
+
+ intel_iommu_detach_device(domain, pdev);
+
+ printk(KERN_DEBUG "deassign device: host bdf = %x:%x:%x\n",
+ assigned_dev->host_busnr,
+ PCI_SLOT(assigned_dev->host_devfn),
+ PCI_FUNC(assigned_dev->host_devfn));
+
+ return 0;
+}
+
int kvm_iommu_map_guest(struct kvm *kvm)
{
int r;
--
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