4 #include "types.h" // u64
5 #include "memmap.h" // PAGE_SIZE
8 #define PAGE_MASK (PAGE_SIZE-1)
10 #define virt_to_phys(v) (unsigned long)(v)
11 #define phys_to_virt(p) (void*)(p)
12 #define wmb() barrier()
13 #define mb() barrier()
15 /* Status byte for guest to report progress, and synchronize features. */
16 /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
17 #define VIRTIO_CONFIG_S_ACKNOWLEDGE 1
18 /* We have found a driver for the device. */
19 #define VIRTIO_CONFIG_S_DRIVER 2
20 /* Driver has used its parts of the config, and is happy */
21 #define VIRTIO_CONFIG_S_DRIVER_OK 4
22 /* We've given up on this device. */
23 #define VIRTIO_CONFIG_S_FAILED 0x80
25 #define MAX_QUEUE_NUM (128)
27 #define VRING_DESC_F_NEXT 1
28 #define VRING_DESC_F_WRITE 2
30 #define VRING_AVAIL_F_NO_INTERRUPT 1
32 #define VRING_USED_F_NO_NOTIFY 1
49 struct vring_used_elem
59 struct vring_used_elem ring[];
64 struct vring_desc *desc;
65 struct vring_avail *avail;
66 struct vring_used *used;
69 #define vring_size(num) \
70 (((((sizeof(struct vring_desc) * num) + \
71 (sizeof(struct vring_avail) + sizeof(u16) * num)) \
72 + PAGE_MASK) & ~PAGE_MASK) + \
73 (sizeof(struct vring_used) + sizeof(struct vring_used_elem) * num))
75 typedef unsigned char virtio_queue_t[vring_size(MAX_QUEUE_NUM)];
77 struct vring_virtqueue {
82 u16 vdata[MAX_QUEUE_NUM];
92 static inline void vring_init(struct vring *vr,
93 unsigned int num, unsigned char *queue)
101 /* physical address of desc must be page aligned */
103 pa = virt_to_phys(queue);
104 pa = (pa + PAGE_MASK) & ~PAGE_MASK;
105 vr->desc = phys_to_virt(pa);
107 vr->avail = (struct vring_avail *)&vr->desc[num];
109 /* physical address of used must be page aligned */
111 pa = virt_to_phys(&vr->avail->ring[num]);
112 pa = (pa + PAGE_MASK) & ~PAGE_MASK;
113 vr->used = phys_to_virt(pa);
115 for (i = 0; i < num - 1; i++)
116 vr->desc[i].next = i + 1;
117 vr->desc[i].next = 0;
120 int vring_more_used(struct vring_virtqueue *vq);
121 void vring_detach(struct vring_virtqueue *vq, unsigned int head);
122 int vring_get_buf(struct vring_virtqueue *vq, unsigned int *len);
123 void vring_add_buf(struct vring_virtqueue *vq, struct vring_list list[],
124 unsigned int out, unsigned int in,
125 int index, int num_added);
126 void vring_kick(unsigned int ioaddr, struct vring_virtqueue *vq, int num_added);
128 #endif /* _VIRTIO_RING_H_ */