| virtio_ring.h (228301) | virtio_ring.h (234270) |
|---|---|
| 1/*- 2 * Copyright Rusty Russell IBM Corporation 2007. 3 * 4 * This header is BSD licensed so anyone can use the definitions to implement 5 * compatible drivers/servers. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions --- 13 unchanged lines hidden (view full) --- 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * | 1/*- 2 * Copyright Rusty Russell IBM Corporation 2007. 3 * 4 * This header is BSD licensed so anyone can use the definitions to implement 5 * compatible drivers/servers. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions --- 13 unchanged lines hidden (view full) --- 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * |
| 30 * $FreeBSD: head/sys/dev/virtio/virtio_ring.h 228301 2011-12-06 06:28:32Z grehan $ | 30 * $FreeBSD: head/sys/dev/virtio/virtio_ring.h 234270 2012-04-14 05:48:04Z grehan $ |
| 31 */ 32 33#ifndef VIRTIO_RING_H 34#define VIRTIO_RING_H 35 36#include <sys/types.h> 37 38/* This marks a buffer as continuing via the next field. */ --- 59 unchanged lines hidden (view full) --- 98 * struct vring { 99 * // The actual descriptors (16 bytes each) 100 * struct vring_desc desc[num]; 101 * 102 * // A ring of available descriptor heads with free-running index. 103 * __u16 avail_flags; 104 * __u16 avail_idx; 105 * __u16 available[num]; | 31 */ 32 33#ifndef VIRTIO_RING_H 34#define VIRTIO_RING_H 35 36#include <sys/types.h> 37 38/* This marks a buffer as continuing via the next field. */ --- 59 unchanged lines hidden (view full) --- 98 * struct vring { 99 * // The actual descriptors (16 bytes each) 100 * struct vring_desc desc[num]; 101 * 102 * // A ring of available descriptor heads with free-running index. 103 * __u16 avail_flags; 104 * __u16 avail_idx; 105 * __u16 available[num]; |
| 106 * __u16 used_event_idx; |
|
| 106 * 107 * // Padding to the next align boundary. 108 * char pad[]; 109 * 110 * // A ring of used descriptor heads with free-running index. 111 * __u16 used_flags; 112 * __u16 used_idx; 113 * struct vring_used_elem used[num]; | 107 * 108 * // Padding to the next align boundary. 109 * char pad[]; 110 * 111 * // A ring of used descriptor heads with free-running index. 112 * __u16 used_flags; 113 * __u16 used_idx; 114 * struct vring_used_elem used[num]; |
| 115 * __u16 avail_event_idx; |
|
| 114 * }; 115 * 116 * NOTE: for VirtIO PCI, align is 4096. 117 */ 118 | 116 * }; 117 * 118 * NOTE: for VirtIO PCI, align is 4096. 119 */ 120 |
| 121/* 122 * We publish the used event index at the end of the available ring, and vice 123 * versa. They are at the end for backwards compatibility. 124 */ 125#define vring_used_event(vr) ((vr)->avail->ring[(vr)->num]) 126#define vring_avail_event(vr) (*(uint16_t *)&(vr)->used->ring[(vr)->num]) 127 |
|
| 119static inline int 120vring_size(unsigned int num, unsigned long align) 121{ 122 int size; 123 124 size = num * sizeof(struct vring_desc); 125 size += sizeof(struct vring_avail) + (num * sizeof(uint16_t)); 126 size = (size + align - 1) & ~(align - 1); --- 8 unchanged lines hidden (view full) --- 135{ 136 vr->num = num; 137 vr->desc = (struct vring_desc *) p; 138 vr->avail = (struct vring_avail *) (p + 139 num * sizeof(struct vring_desc)); 140 vr->used = (void *) 141 (((unsigned long) &vr->avail->ring[num] + align-1) & ~(align-1)); 142} | 128static inline int 129vring_size(unsigned int num, unsigned long align) 130{ 131 int size; 132 133 size = num * sizeof(struct vring_desc); 134 size += sizeof(struct vring_avail) + (num * sizeof(uint16_t)); 135 size = (size + align - 1) & ~(align - 1); --- 8 unchanged lines hidden (view full) --- 144{ 145 vr->num = num; 146 vr->desc = (struct vring_desc *) p; 147 vr->avail = (struct vring_avail *) (p + 148 num * sizeof(struct vring_desc)); 149 vr->used = (void *) 150 (((unsigned long) &vr->avail->ring[num] + align-1) & ~(align-1)); 151} |
| 152 153/* 154 * The following is used with VIRTIO_RING_F_EVENT_IDX. 155 * 156 * Assuming a given event_idx value from the other size, if we have 157 * just incremented index from old to new_idx, should we trigger an 158 * event? 159 */ 160static inline int 161vring_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old) 162{ 163 164 return (uint16_t)(new_idx - event_idx - 1) < (uint16_t)(new_idx - old); 165} |
|
| 143#endif /* VIRTIO_RING_H */ | 166#endif /* VIRTIO_RING_H */ |