Commit c1e01514 authored by Sheng Yang's avatar Sheng Yang Committed by Avi Kivity
Browse files

KVM: Ioctls for init MSI-X entry 



Introduce KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY two ioctls.

This two ioctls are used by userspace to specific guest device MSI-X entry
number and correlate MSI-X entry with GSI during the initialization stage.

MSI-X should be well initialzed before enabling.

Don't support change MSI-X entry number for now.

Signed-off-by: default avatarSheng Yang <sheng@linux.intel.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent bfd349d0

include/linux/kvm.h

+18 −0
Original line number Diff line number Diff line
@@ -487,6 +487,10 @@ struct kvm_irq_routing { 
#define KVM_REINJECT_CONTROL      _IO(KVMIO, 0x71)

#define KVM_DEASSIGN_PCI_DEVICE _IOW(KVMIO, 0x72, \

				     struct kvm_assigned_pci_dev)

#define KVM_ASSIGN_SET_MSIX_NR \

			_IOW(KVMIO, 0x73, struct kvm_assigned_msix_nr)

#define KVM_ASSIGN_SET_MSIX_ENTRY \

			_IOW(KVMIO, 0x74, struct kvm_assigned_msix_entry)



/*

 * ioctls for vcpu fds
@@ -607,4 +611,18 @@ struct kvm_assigned_irq { 
#define KVM_DEV_IRQ_ASSIGN_MSI_ACTION	KVM_DEV_IRQ_ASSIGN_ENABLE_MSI

#define KVM_DEV_IRQ_ASSIGN_ENABLE_MSI	(1 << 0)



struct kvm_assigned_msix_nr {

	__u32 assigned_dev_id;

	__u16 entry_nr;

	__u16 padding;

};



#define KVM_MAX_MSIX_PER_DEV		512

struct kvm_assigned_msix_entry {

	__u32 assigned_dev_id;

	__u32 gsi;

	__u16 entry; /* The index of entry in the MSI-X table */

	__u16 padding[3];

};



#endif

include/linux/kvm_host.h

+10 −0
Original line number Diff line number Diff line
@@ -319,6 +319,12 @@ struct kvm_irq_ack_notifier { 
	void (*irq_acked)(struct kvm_irq_ack_notifier *kian);

};



struct kvm_guest_msix_entry {

	u32 vector;

	u16 entry;

	u16 flags;

};



struct kvm_assigned_dev_kernel {

	struct kvm_irq_ack_notifier ack_notifier;

	struct work_struct interrupt_work;
@@ -326,13 +332,17 @@ struct kvm_assigned_dev_kernel { 
	int assigned_dev_id;

	int host_busnr;

	int host_devfn;

	unsigned int entries_nr;

	int host_irq;

	bool host_irq_disabled;

	struct msix_entry *host_msix_entries;

	int guest_irq;

	struct kvm_guest_msix_entry *guest_msix_entries;

#define KVM_ASSIGNED_DEV_GUEST_INTX	(1 << 0)

#define KVM_ASSIGNED_DEV_GUEST_MSI	(1 << 1)

#define KVM_ASSIGNED_DEV_HOST_INTX	(1 << 8)

#define KVM_ASSIGNED_DEV_HOST_MSI	(1 << 9)

#define KVM_ASSIGNED_DEV_MSIX		((1 << 2) | (1 << 10))

	unsigned long irq_requested_type;

	int irq_source_id;

	int flags;

virt/kvm/kvm_main.c

+104 −0
Original line number Diff line number Diff line
@@ -1593,6 +1593,88 @@ static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset) 
	return 0;

}



#ifdef __KVM_HAVE_MSIX

static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,

				    struct kvm_assigned_msix_nr *entry_nr)

{

	int r = 0;

	struct kvm_assigned_dev_kernel *adev;



	mutex_lock(&kvm->lock);



	adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,

				      entry_nr->assigned_dev_id);

	if (!adev) {

		r = -EINVAL;

		goto msix_nr_out;

	}



	if (adev->entries_nr == 0) {

		adev->entries_nr = entry_nr->entry_nr;

		if (adev->entries_nr == 0 ||

		    adev->entries_nr >= KVM_MAX_MSIX_PER_DEV) {

			r = -EINVAL;

			goto msix_nr_out;

		}



		adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *

						entry_nr->entry_nr,

						GFP_KERNEL);

		if (!adev->host_msix_entries) {

			r = -ENOMEM;

			goto msix_nr_out;

		}

		adev->guest_msix_entries = kzalloc(

				sizeof(struct kvm_guest_msix_entry) *

				entry_nr->entry_nr, GFP_KERNEL);

		if (!adev->guest_msix_entries) {

			kfree(adev->host_msix_entries);

			r = -ENOMEM;

			goto msix_nr_out;

		}

	} else /* Not allowed set MSI-X number twice */

		r = -EINVAL;

msix_nr_out:

	mutex_unlock(&kvm->lock);

	return r;

}



static int kvm_vm_ioctl_set_msix_entry(struct kvm *kvm,

				       struct kvm_assigned_msix_entry *entry)

{

	int r = 0, i;

	struct kvm_assigned_dev_kernel *adev;



	mutex_lock(&kvm->lock);



	adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,

				      entry->assigned_dev_id);



	if (!adev) {

		r = -EINVAL;

		goto msix_entry_out;

	}



	for (i = 0; i < adev->entries_nr; i++)

		if (adev->guest_msix_entries[i].vector == 0 ||

		    adev->guest_msix_entries[i].entry == entry->entry) {

			adev->guest_msix_entries[i].entry = entry->entry;

			adev->guest_msix_entries[i].vector = entry->gsi;

			adev->host_msix_entries[i].entry = entry->entry;

			break;

		}

	if (i == adev->entries_nr) {

		r = -ENOSPC;

		goto msix_entry_out;

	}



msix_entry_out:

	mutex_unlock(&kvm->lock);



	return r;

}

#endif



static long kvm_vcpu_ioctl(struct file *filp,

			   unsigned int ioctl, unsigned long arg)

{
@@ -1917,7 +1999,29 @@ static long kvm_vm_ioctl(struct file *filp, 
		vfree(entries);

		break;

	}

#ifdef __KVM_HAVE_MSIX

	case KVM_ASSIGN_SET_MSIX_NR: {

		struct kvm_assigned_msix_nr entry_nr;

		r = -EFAULT;

		if (copy_from_user(&entry_nr, argp, sizeof entry_nr))

			goto out;

		r = kvm_vm_ioctl_set_msix_nr(kvm, &entry_nr);

		if (r)

			goto out;

		break;

	}

	case KVM_ASSIGN_SET_MSIX_ENTRY: {

		struct kvm_assigned_msix_entry entry;

		r = -EFAULT;

		if (copy_from_user(&entry, argp, sizeof entry))

			goto out;

		r = kvm_vm_ioctl_set_msix_entry(kvm, &entry);

		if (r)

			goto out;

		break;

	}

#endif

#endif /* KVM_CAP_IRQ_ROUTING */

	default:

		r = kvm_arch_vm_ioctl(filp, ioctl, arg);

	}

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