1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 3 #ifndef __KVM_IODEV_H__ 4 #define __KVM_IODEV_H__ 5 6 #include <linux/kvm_types.h> 7 #include <linux/errno.h> 8 9 struct kvm_io_device; 10 struct kvm_vcpu; 11 12 /** 13 * kvm_io_device_ops are called under kvm slots_lock. 14 * read and write handlers return 0 if the transaction has been handled, 15 * or non-zero to have it passed to the next device. 16 **/ 17 struct kvm_io_device_ops { 18 int (*read)(struct kvm_vcpu *vcpu, 19 struct kvm_io_device *this, 20 gpa_t addr, 21 int len, 22 void *val); 23 int (*write)(struct kvm_vcpu *vcpu, 24 struct kvm_io_device *this, 25 gpa_t addr, 26 int len, 27 const void *val); 28 void (*destructor)(struct kvm_io_device *this); 29 }; 30 31 32 struct kvm_io_device { 33 const struct kvm_io_device_ops *ops; 34 }; 35 36 static inline void kvm_iodevice_init(struct kvm_io_device *dev, 37 const struct kvm_io_device_ops *ops) 38 { 39 dev->ops = ops; 40 } 41 42 static inline int kvm_iodevice_read(struct kvm_vcpu *vcpu, 43 struct kvm_io_device *dev, gpa_t addr, 44 int l, void *v) 45 { 46 return dev->ops->read ? dev->ops->read(vcpu, dev, addr, l, v) 47 : -EOPNOTSUPP; 48 } 49 50 static inline int kvm_iodevice_write(struct kvm_vcpu *vcpu, 51 struct kvm_io_device *dev, gpa_t addr, 52 int l, const void *v) 53 { 54 return dev->ops->write ? dev->ops->write(vcpu, dev, addr, l, v) 55 : -EOPNOTSUPP; 56 } 57 58 #endif /* __KVM_IODEV_H__ */ 59