libqos: Added EVENT_IDX support

Added avail_event and NO_NOTIFY check before notifying.
Added used_event setting.

Signed-off-by: Marc Marí <marc.mari.barcelo@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Marc Marí 2014-09-01 12:08:00 +02:00 committed by Stefan Hajnoczi
parent 5836811398
commit 1053587c3f
4 changed files with 156 additions and 1 deletions

View file

@ -203,6 +203,7 @@ static QVirtQueue *qvirtio_pci_virtqueue_setup(QVirtioDevice *d,
vqpci->vq.num_free = vqpci->vq.size;
vqpci->vq.align = QVIRTIO_PCI_ALIGN;
vqpci->vq.indirect = (feat & QVIRTIO_F_RING_INDIRECT_DESC) != 0;
vqpci->vq.event = (feat & QVIRTIO_F_RING_EVENT_IDX) != 0;
vqpci->msix_entry = -1;
vqpci->msix_addr = 0;

View file

@ -124,9 +124,13 @@ void qvring_init(const QGuestAllocator *alloc, QVirtQueue *vq, uint64_t addr)
writew(vq->avail, 0);
/* vq->avail->idx */
writew(vq->avail + 2, 0);
/* vq->avail->used_event */
writew(vq->avail + 4 + (2 * vq->size), 0);
/* vq->used->flags */
writew(vq->used, 0);
/* vq->used->avail_event */
writew(vq->used+2+(sizeof(struct QVRingUsedElem)*vq->size), 0);
}
QVRingIndirectDesc *qvring_indirect_desc_setup(QVirtioDevice *d,
@ -222,11 +226,32 @@ void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq,
{
/* vq->avail->idx */
uint16_t idx = readl(vq->avail + 2);
/* vq->used->flags */
uint16_t flags;
/* vq->used->avail_event */
uint16_t avail_event;
/* vq->avail->ring[idx % vq->size] */
writel(vq->avail + 4 + (2 * (idx % vq->size)), free_head);
/* vq->avail->idx */
writel(vq->avail + 2, idx + 1);
bus->virtqueue_kick(d, vq);
/* Must read after idx is updated */
flags = readw(vq->avail);
avail_event = readw(vq->used + 4 +
(sizeof(struct QVRingUsedElem) * vq->size));
/* < 1 because we add elements to avail queue one by one */
if ((flags & QVRING_USED_F_NO_NOTIFY) == 0 &&
(!vq->event || (uint16_t)(idx-avail_event) < 1)) {
bus->virtqueue_kick(d, vq);
}
}
void qvirtqueue_set_used_event(QVirtQueue *vq, uint16_t idx)
{
g_assert(vq->event);
/* vq->avail->used_event */
writew(vq->avail + 4 + (2 * vq->size), idx);
}

View file

@ -26,6 +26,7 @@
#define QVIRTIO_F_ANY_LAYOUT 0x08000000
#define QVIRTIO_F_RING_INDIRECT_DESC 0x10000000
#define QVIRTIO_F_RING_EVENT_IDX 0x20000000
#define QVIRTIO_F_BAD_FEATURE 0x40000000
#define QVRING_DESC_F_NEXT 0x1
#define QVRING_DESC_F_WRITE 0x2
@ -57,6 +58,7 @@ typedef struct QVRingAvail {
uint16_t flags;
uint16_t idx;
uint16_t ring[0]; /* This is an array of uint16_t */
uint16_t used_event;
} QVRingAvail;
typedef struct QVRingUsedElem {
@ -68,6 +70,7 @@ typedef struct QVRingUsed {
uint16_t flags;
uint16_t idx;
QVRingUsedElem ring[0]; /* This is an array of QVRingUsedElem structs */
uint16_t avail_event;
} QVRingUsed;
typedef struct QVirtQueue {
@ -80,6 +83,7 @@ typedef struct QVirtQueue {
uint32_t num_free;
uint32_t align;
bool indirect;
bool event;
} QVirtQueue;
typedef struct QVRingIndirectDesc {
@ -174,4 +178,5 @@ uint32_t qvirtqueue_add_indirect(QVirtQueue *vq, QVRingIndirectDesc *indirect);
void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq,
uint32_t free_head);
void qvirtqueue_set_used_event(QVirtQueue *vq, uint16_t idx);
#endif