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	This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write functions. in_range now becomes unused so it is removed from device ops in favor of read/write callbacks performing range checks internally. This allows aliasing (mostly for in-kernel virtio), as well as better error handling by making it possible to pass errors up to userspace. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
		
			
				
	
	
		
			70 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			70 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
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 */
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#ifndef __KVM_IODEV_H__
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#define __KVM_IODEV_H__
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#include <linux/kvm_types.h>
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#include <asm/errno.h>
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struct kvm_io_device;
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/**
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 * kvm_io_device_ops are called under kvm slots_lock.
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 * read and write handlers return 0 if the transaction has been handled,
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 * or non-zero to have it passed to the next device.
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 **/
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struct kvm_io_device_ops {
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	int (*read)(struct kvm_io_device *this,
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		    gpa_t addr,
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		    int len,
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		    void *val);
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	int (*write)(struct kvm_io_device *this,
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		     gpa_t addr,
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		     int len,
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		     const void *val);
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	void (*destructor)(struct kvm_io_device *this);
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};
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struct kvm_io_device {
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	const struct kvm_io_device_ops *ops;
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};
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static inline void kvm_iodevice_init(struct kvm_io_device *dev,
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				     const struct kvm_io_device_ops *ops)
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{
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	dev->ops = ops;
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}
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static inline int kvm_iodevice_read(struct kvm_io_device *dev,
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				    gpa_t addr, int l, void *v)
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{
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	return dev->ops->read ? dev->ops->read(dev, addr, l, v) : -EOPNOTSUPP;
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}
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static inline int kvm_iodevice_write(struct kvm_io_device *dev,
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				     gpa_t addr, int l, const void *v)
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{
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	return dev->ops->write ? dev->ops->write(dev, addr, l, v) : -EOPNOTSUPP;
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}
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static inline void kvm_iodevice_destructor(struct kvm_io_device *dev)
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{
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	if (dev->ops->destructor)
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		dev->ops->destructor(dev);
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}
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#endif /* __KVM_IODEV_H__ */
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