1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License as published by 4 * the Free Software Foundation; either version 2 of the License. 5 * 6 * This program is distributed in the hope that it will be useful, 7 * but WITHOUT ANY WARRANTY; without even the implied warranty of 8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 9 * GNU General Public License for more details. 10 * 11 * You should have received a copy of the GNU General Public License 12 * along with this program. If not, see <http://www.gnu.org/licenses/>. 13 */ 14 15 #ifndef __KVM_IODEV_H__ 16 #define __KVM_IODEV_H__ 17 18 #include <linux/kvm_types.h> 19 #include <linux/errno.h> 20 21 struct kvm_io_device; 22 struct kvm_vcpu; 23 24 /** 25 * kvm_io_device_ops are called under kvm slots_lock. 26 * read and write handlers return 0 if the transaction has been handled, 27 * or non-zero to have it passed to the next device. 28 **/ 29 struct kvm_io_device_ops { 30 int (*read)(struct kvm_vcpu *vcpu, 31 struct kvm_io_device *this, 32 gpa_t addr, 33 int len, 34 void *val); 35 int (*write)(struct kvm_vcpu *vcpu, 36 struct kvm_io_device *this, 37 gpa_t addr, 38 int len, 39 const void *val); 40 void (*destructor)(struct kvm_io_device *this); 41 }; 42 43 44 struct kvm_io_device { 45 const struct kvm_io_device_ops *ops; 46 }; 47 48 static inline void kvm_iodevice_init(struct kvm_io_device *dev, 49 const struct kvm_io_device_ops *ops) 50 { 51 dev->ops = ops; 52 } 53 54 static inline int kvm_iodevice_read(struct kvm_vcpu *vcpu, 55 struct kvm_io_device *dev, gpa_t addr, 56 int l, void *v) 57 { 58 return dev->ops->read ? dev->ops->read(vcpu, dev, addr, l, v) 59 : -EOPNOTSUPP; 60 } 61 62 static inline int kvm_iodevice_write(struct kvm_vcpu *vcpu, 63 struct kvm_io_device *dev, gpa_t addr, 64 int l, const void *v) 65 { 66 return dev->ops->write ? dev->ops->write(vcpu, dev, addr, l, v) 67 : -EOPNOTSUPP; 68 } 69 70 static inline void kvm_iodevice_destructor(struct kvm_io_device *dev) 71 { 72 if (dev->ops->destructor) 73 dev->ops->destructor(dev); 74 } 75 76 #endif /* __KVM_IODEV_H__ */ 77