From ccc9d90a9a8b5c4ad7e9708ec41f75ff9e98d61d Mon Sep 17 00:00:00 2001 From: Wei Liu Date: Fri, 3 Apr 2015 14:44:59 +0800 Subject: xenbus_client: Extend interface to support multi-page ring Originally Xen PV drivers only use single-page ring to pass along information. This might limit the throughput between frontend and backend. The patch extends Xenbus driver to support multi-page ring, which in general should improve throughput if ring is the bottleneck. Changes to various frontend / backend to adapt to the new interface are also included. Affected Xen drivers: * blkfront/back * netfront/back * pcifront/back * scsifront/back * vtpmfront The interface is documented, as before, in xenbus_client.c. Signed-off-by: Wei Liu Signed-off-by: Paul Durrant Signed-off-by: Bob Liu Cc: Konrad Wilk Cc: Boris Ostrovsky Signed-off-by: David Vrabel --- drivers/scsi/xen-scsifront.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/scsi/xen-scsifront.c') diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c index 78d9506..fad22ca 100644 --- a/drivers/scsi/xen-scsifront.c +++ b/drivers/scsi/xen-scsifront.c @@ -714,6 +714,7 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info) { struct xenbus_device *dev = info->dev; struct vscsiif_sring *sring; + grant_ref_t gref; int err = -ENOMEM; /***** Frontend to Backend ring start *****/ @@ -726,14 +727,14 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info) SHARED_RING_INIT(sring); FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE); - err = xenbus_grant_ring(dev, virt_to_mfn(sring)); + err = xenbus_grant_ring(dev, sring, 1, &gref); if (err < 0) { free_page((unsigned long)sring); xenbus_dev_fatal(dev, err, "fail to grant shared ring (Front to Back)"); return err; } - info->ring_ref = err; + info->ring_ref = gref; err = xenbus_alloc_evtchn(dev, &info->evtchn); if (err) { -- cgit v1.1