diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c index 1e8cfd80a4e6..4acc4e899600 100644 --- a/drivers/xen/xen-scsiback.c +++ b/drivers/xen/xen-scsiback.c @@ -91,7 +91,6 @@ struct vscsibk_info { unsigned int irq; struct vscsiif_back_ring ring; - int ring_error; spinlock_t ring_lock; atomic_t nr_unreplied_reqs; @@ -722,7 +721,8 @@ static struct vscsibk_pend *prepare_pending_reqs(struct vscsibk_info *info, return pending_req; } -static int scsiback_do_cmd_fn(struct vscsibk_info *info) +static int scsiback_do_cmd_fn(struct vscsibk_info *info, + unsigned int *eoi_flags) { struct vscsiif_back_ring *ring = &info->ring; struct vscsiif_request ring_req; @@ -739,11 +739,12 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) rc = ring->rsp_prod_pvt; pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n", info->domid, rp, rc, rp - rc); - info->ring_error = 1; - return 0; + return -EINVAL; } while ((rc != rp)) { + *eoi_flags &= ~XEN_EOI_FLAG_SPURIOUS; + if (RING_REQUEST_CONS_OVERFLOW(ring, rc)) break; @@ -802,13 +803,16 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) static irqreturn_t scsiback_irq_fn(int irq, void *dev_id) { struct vscsibk_info *info = dev_id; + int rc; + unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS; - if (info->ring_error) - return IRQ_HANDLED; - - while (scsiback_do_cmd_fn(info)) + while ((rc = scsiback_do_cmd_fn(info, &eoi_flags)) > 0) cond_resched(); + /* In case of a ring error we keep the event channel masked. */ + if (!rc) + xen_irq_lateeoi(irq, eoi_flags); + return IRQ_HANDLED; } @@ -829,7 +833,7 @@ static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref, sring = (struct vscsiif_sring *)area; BACK_RING_INIT(&info->ring, sring, PAGE_SIZE); - err = bind_interdomain_evtchn_to_irq(info->domid, evtchn); + err = bind_interdomain_evtchn_to_irq_lateeoi(info->domid, evtchn); if (err < 0) goto unmap_page; @@ -1253,7 +1257,6 @@ static int scsiback_probe(struct xenbus_device *dev, info->domid = dev->otherend_id; spin_lock_init(&info->ring_lock); - info->ring_error = 0; atomic_set(&info->nr_unreplied_reqs, 0); init_waitqueue_head(&info->waiting_to_free); info->dev = dev;