virtio: introduce qemu_get/put_virtqueue_element

Move allocation to virtio functions also when loading/saving a
VirtQueueElement.  This will also let the load/save functions
keep backwards compatibility when the VirtQueueElement layout
is changed.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Paolo Bonzini 2016-01-31 11:28:59 +01:00 committed by Michael S. Tsirkin
parent 51b19ebe43
commit ab281c1781
5 changed files with 23 additions and 19 deletions

View File

@ -808,8 +808,7 @@ static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f)
while (req) {
qemu_put_sbyte(f, 1);
qemu_put_buffer(f, (unsigned char *)&req->elem,
sizeof(VirtQueueElement));
qemu_put_virtqueue_element(f, &req->elem);
req = req->next;
}
qemu_put_sbyte(f, 0);
@ -832,14 +831,11 @@ static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
VirtIOBlock *s = VIRTIO_BLK(vdev);
while (qemu_get_sbyte(f)) {
VirtIOBlockReq *req = g_new(VirtIOBlockReq, 1);
VirtIOBlockReq *req;
req = qemu_get_virtqueue_element(f, sizeof(VirtIOBlockReq));
virtio_blk_init_request(s, req);
qemu_get_buffer(f, (unsigned char *)&req->elem,
sizeof(VirtQueueElement));
req->next = s->rq;
s->rq = req;
virtqueue_map(&req->elem);
}
return 0;

View File

@ -646,9 +646,7 @@ static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f)
if (elem_popped) {
qemu_put_be32s(f, &port->iov_idx);
qemu_put_be64s(f, &port->iov_offset);
qemu_put_buffer(f, (unsigned char *)port->elem,
sizeof(VirtQueueElement));
qemu_put_virtqueue_element(f, port->elem);
}
}
}
@ -723,10 +721,8 @@ static int fetch_active_ports_list(QEMUFile *f, int version_id,
qemu_get_be32s(f, &port->iov_idx);
qemu_get_be64s(f, &port->iov_offset);
port->elem = g_new(VirtQueueElement, 1);
qemu_get_buffer(f, (unsigned char *)port->elem,
sizeof(VirtQueueElement));
virtqueue_map(port->elem);
port->elem =
qemu_get_virtqueue_element(f, sizeof(VirtQueueElement));
/*
* Port was throttled on source machine. Let's

View File

@ -189,7 +189,7 @@ static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq)
assert(n < vs->conf.num_queues);
qemu_put_be32s(f, &n);
qemu_put_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
qemu_put_virtqueue_element(f, &req->elem);
}
static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
@ -202,12 +202,9 @@ static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
qemu_get_be32s(f, &n);
assert(n < vs->conf.num_queues);
req = g_malloc(sizeof(VirtIOSCSIReq) + vs->cdb_size);
qemu_get_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
req = qemu_get_virtqueue_element(f, sizeof(VirtIOSCSIReq) + vs->cdb_size);
virtio_scsi_init_req(s, vs->cmd_vqs[n], req);
virtqueue_map(&req->elem);
if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size,
sizeof(VirtIOSCSICmdResp) + vs->sense_size) < 0) {
error_report("invalid SCSI request migration data");

View File

@ -576,6 +576,19 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
return elem;
}
void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz)
{
VirtQueueElement *elem = g_malloc(sz);
qemu_get_buffer(f, (uint8_t *)elem, sizeof(VirtQueueElement));
virtqueue_map(elem);
return elem;
}
void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem)
{
qemu_put_buffer(f, (uint8_t *)elem, sizeof(VirtQueueElement));
}
/* virtio device */
static void virtio_notify_vector(VirtIODevice *vdev, uint16_t vector)
{

View File

@ -153,6 +153,8 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
void virtqueue_map(VirtQueueElement *elem);
void *virtqueue_pop(VirtQueue *vq, size_t sz);
void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz);
void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
unsigned int out_bytes);
void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,