Commit d60eacb0 authored by Will Deacon's avatar Will Deacon Committed by Paolo Bonzini
Browse files

KVM: device: add simple registration mechanism for kvm_device_ops 



kvm_ioctl_create_device currently has knowledge of all the device types
and their associated ops. This is fairly inflexible when adding support
for new in-kernel device emulations, so move what we currently have out
into a table, which can support dynamic registration of ops by new
drivers for virtual hardware.

Cc: Alex Williamson <Alex.Williamson@redhat.com>
Cc: Alex Graf <agraf@suse.de>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: default avatarChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 184564ef

include/linux/kvm_host.h

+1 −0
Original line number Diff line number Diff line
@@ -1064,6 +1064,7 @@ struct kvm_device_ops { 
void kvm_device_get(struct kvm_device *dev);

void kvm_device_put(struct kvm_device *dev);

struct kvm_device *kvm_device_from_filp(struct file *filp);

int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type);



extern struct kvm_device_ops kvm_mpic_ops;

extern struct kvm_device_ops kvm_xics_ops;

include/uapi/linux/kvm.h

+16 −6
Original line number Diff line number Diff line
@@ -943,15 +943,25 @@ struct kvm_device_attr { 
	__u64	addr;		/* userspace address of attr data */

};



#define KVM_DEV_TYPE_FSL_MPIC_20	1

#define KVM_DEV_TYPE_FSL_MPIC_42	2

#define KVM_DEV_TYPE_XICS		3

#define KVM_DEV_TYPE_VFIO		4

#define  KVM_DEV_VFIO_GROUP			1

#define   KVM_DEV_VFIO_GROUP_ADD			1

#define   KVM_DEV_VFIO_GROUP_DEL			2

#define KVM_DEV_TYPE_ARM_VGIC_V2	5

#define KVM_DEV_TYPE_FLIC		6



enum kvm_device_type {

	KVM_DEV_TYPE_FSL_MPIC_20	= 1,

#define KVM_DEV_TYPE_FSL_MPIC_20	KVM_DEV_TYPE_FSL_MPIC_20

	KVM_DEV_TYPE_FSL_MPIC_42,

#define KVM_DEV_TYPE_FSL_MPIC_42	KVM_DEV_TYPE_FSL_MPIC_42

	KVM_DEV_TYPE_XICS,

#define KVM_DEV_TYPE_XICS		KVM_DEV_TYPE_XICS

	KVM_DEV_TYPE_VFIO,

#define KVM_DEV_TYPE_VFIO		KVM_DEV_TYPE_VFIO

	KVM_DEV_TYPE_ARM_VGIC_V2,

#define KVM_DEV_TYPE_ARM_VGIC_V2	KVM_DEV_TYPE_ARM_VGIC_V2

	KVM_DEV_TYPE_FLIC,

#define KVM_DEV_TYPE_FLIC		KVM_DEV_TYPE_FLIC

	KVM_DEV_TYPE_MAX,

};



/*

 * ioctls for VM fds

virt/kvm/kvm_main.c

+38 −27
Original line number Diff line number Diff line
@@ -2272,45 +2272,56 @@ struct kvm_device *kvm_device_from_filp(struct file *filp) 
	return filp->private_data;

}



static int kvm_ioctl_create_device(struct kvm *kvm,

				   struct kvm_create_device *cd)

{

	struct kvm_device_ops *ops = NULL;

	struct kvm_device *dev;

	bool test = cd->flags & KVM_CREATE_DEVICE_TEST;

	int ret;



	switch (cd->type) {

static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {

#ifdef CONFIG_KVM_MPIC

	case KVM_DEV_TYPE_FSL_MPIC_20:

	case KVM_DEV_TYPE_FSL_MPIC_42:

		ops = &kvm_mpic_ops;

		break;

	[KVM_DEV_TYPE_FSL_MPIC_20]	= &kvm_mpic_ops,

	[KVM_DEV_TYPE_FSL_MPIC_42]	= &kvm_mpic_ops,

#endif



#ifdef CONFIG_KVM_XICS

	case KVM_DEV_TYPE_XICS:

		ops = &kvm_xics_ops;

		break;

	[KVM_DEV_TYPE_XICS]		= &kvm_xics_ops,

#endif



#ifdef CONFIG_KVM_VFIO

	case KVM_DEV_TYPE_VFIO:

		ops = &kvm_vfio_ops;

		break;

	[KVM_DEV_TYPE_VFIO]		= &kvm_vfio_ops,

#endif



#ifdef CONFIG_KVM_ARM_VGIC

	case KVM_DEV_TYPE_ARM_VGIC_V2:

		ops = &kvm_arm_vgic_v2_ops;

		break;

	[KVM_DEV_TYPE_ARM_VGIC_V2]	= &kvm_arm_vgic_v2_ops,

#endif



#ifdef CONFIG_S390

	case KVM_DEV_TYPE_FLIC:

		ops = &kvm_flic_ops;

		break;

	[KVM_DEV_TYPE_FLIC]		= &kvm_flic_ops,

#endif

	default:

		return -ENODEV;

};



int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)

{

	if (type >= ARRAY_SIZE(kvm_device_ops_table))

		return -ENOSPC;



	if (kvm_device_ops_table[type] != NULL)

		return -EEXIST;



	kvm_device_ops_table[type] = ops;

	return 0;

}



static int kvm_ioctl_create_device(struct kvm *kvm,

				   struct kvm_create_device *cd)

{

	struct kvm_device_ops *ops = NULL;

	struct kvm_device *dev;

	bool test = cd->flags & KVM_CREATE_DEVICE_TEST;

	int ret;



	if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))

		return -ENODEV;



	ops = kvm_device_ops_table[cd->type];

	if (ops == NULL)

		return -ENODEV;



	if (test)

		return 0;

CRA Git | Maintained and supported by SUSTech CRA and CCSE