From d60eacb07053142bfb9b41582074a89a790a9d46 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 2 Sep 2014 10:27:33 +0100 Subject: [PATCH] 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 Cc: Alex Graf Cc: Gleb Natapov Cc: Paolo Bonzini Cc: Marc Zyngier Acked-by: Cornelia Huck Reviewed-by: Christoffer Dall Signed-off-by: Will Deacon Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 1 + include/uapi/linux/kvm.h | 22 ++++++++++---- virt/kvm/kvm_main.c | 65 +++++++++++++++++++++++----------------- 3 files changed, 55 insertions(+), 33 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index e098dce179df..b6e954742951 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -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; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 0695a1e3e332..60768822b140 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -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 diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c338599804e0..686d783387a0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2272,44 +2272,55 @@ 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: +}; + +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; -- 2.20.1