| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 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, write to the Free Software |
| 13 | * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
| 14 | */ |
| 15 | |
| 16 | #ifndef __KVM_IODEV_H__ |
| 17 | #define __KVM_IODEV_H__ |
| 18 | |
| 19 | #include <linux/kvm_types.h> |
| 20 | #include <asm/errno.h> |
| 21 | |
| 22 | struct kvm_io_device; |
| 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_io_device *this, |
| 31 | gpa_t addr, |
| 32 | int len, |
| 33 | void *val); |
| 34 | int (*write)(struct kvm_io_device *this, |
| 35 | gpa_t addr, |
| 36 | int len, |
| 37 | const void *val); |
| 38 | void (*destructor)(struct kvm_io_device *this); |
| 39 | }; |
| 40 | |
| 41 | |
| 42 | struct kvm_io_device { |
| 43 | const struct kvm_io_device_ops *ops; |
| 44 | }; |
| 45 | |
| 46 | static inline void kvm_iodevice_init(struct kvm_io_device *dev, |
| 47 | const struct kvm_io_device_ops *ops) |
| 48 | { |
| 49 | dev->ops = ops; |
| 50 | } |
| 51 | |
| 52 | static inline int kvm_iodevice_read(struct kvm_io_device *dev, |
| 53 | gpa_t addr, int l, void *v) |
| 54 | { |
| 55 | return dev->ops->read ? dev->ops->read(dev, addr, l, v) : -EOPNOTSUPP; |
| 56 | } |
| 57 | |
| 58 | static inline int kvm_iodevice_write(struct kvm_io_device *dev, |
| 59 | gpa_t addr, int l, const void *v) |
| 60 | { |
| 61 | return dev->ops->write ? dev->ops->write(dev, addr, l, v) : -EOPNOTSUPP; |
| 62 | } |
| 63 | |
| 64 | static inline void kvm_iodevice_destructor(struct kvm_io_device *dev) |
| 65 | { |
| 66 | if (dev->ops->destructor) |
| 67 | dev->ops->destructor(dev); |
| 68 | } |
| 69 | |
| 70 | #endif /* __KVM_IODEV_H__ */ |