63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
| /* Copyright 2012 Red Hat, Inc. and/or its affiliates
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|  * Copyright IBM, Corp. 2012
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|  *
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|  * Based on Linux 2.6.39 vhost code:
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|  * Copyright (C) 2009 Red Hat, Inc.
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|  * Copyright (C) 2006 Rusty Russell IBM Corporation
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|  *
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|  * Author: Michael S. Tsirkin <mst@redhat.com>
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|  *         Stefan Hajnoczi <stefanha@redhat.com>
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|  *
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|  * Inspiration, some code, and most witty comments come from
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|  * Documentation/virtual/lguest/lguest.c, by Rusty Russell
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|  *
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|  * This work is licensed under the terms of the GNU GPL, version 2.
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|  */
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| 
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| #ifndef VRING_H
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| #define VRING_H
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| 
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| #include <linux/virtio_ring.h>
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| #include "qemu-common.h"
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| #include "hw/dataplane/hostmem.h"
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| #include "hw/virtio.h"
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| 
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| typedef struct {
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|     HostMem hostmem;                /* guest memory mapper */
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|     struct vring vr;                /* virtqueue vring mapped to host memory */
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|     uint16_t last_avail_idx;        /* last processed avail ring index */
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|     uint16_t last_used_idx;         /* last processed used ring index */
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|     uint16_t signalled_used;        /* EVENT_IDX state */
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|     bool signalled_used_valid;
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|     bool broken;                    /* was there a fatal error? */
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| } Vring;
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| 
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| static inline unsigned int vring_get_num(Vring *vring)
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| {
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|     return vring->vr.num;
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| }
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| 
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| /* Are there more descriptors available? */
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| static inline bool vring_more_avail(Vring *vring)
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| {
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|     return vring->vr.avail->idx != vring->last_avail_idx;
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| }
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| 
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| /* Fail future vring_pop() and vring_push() calls until reset */
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| static inline void vring_set_broken(Vring *vring)
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| {
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|     vring->broken = true;
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| }
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| 
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| bool vring_setup(Vring *vring, VirtIODevice *vdev, int n);
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| void vring_teardown(Vring *vring);
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| void vring_disable_notification(VirtIODevice *vdev, Vring *vring);
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| bool vring_enable_notification(VirtIODevice *vdev, Vring *vring);
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| bool vring_should_notify(VirtIODevice *vdev, Vring *vring);
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| int vring_pop(VirtIODevice *vdev, Vring *vring,
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|               struct iovec iov[], struct iovec *iov_end,
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|               unsigned int *out_num, unsigned int *in_num);
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| void vring_push(Vring *vring, unsigned int head, int len);
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| 
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| #endif /* VRING_H */
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