do_poll takes sched_poll* as parameter, but that's actually in guest memory
(so it's more a guest handle). Split its copy from/to guest logic from
the main logic, so that we have a separate vcpu_poll which takes the sched_poll
parameters directly.
Signed-off-by: Teddy Astie <teddy.as...@vates.tech>
---
xen/common/sched/core.c | 40 +++++++++++++++++++++-------------------
1 file changed, 21 insertions(+), 19 deletions(-)
diff --git a/xen/common/sched/core.c b/xen/common/sched/core.c
index 13fdf57e57..b2c784c60e 100644
--- a/xen/common/sched/core.c
+++ b/xen/common/sched/core.c
@@ -1437,21 +1437,13 @@ static void vcpu_block_enable_events(void)
vcpu_block();
}
-static long do_poll(const struct sched_poll *sched_poll)
+static long vcpu_poll(unsigned int nr_ports, uint64_t timeout, evtchn_port_t
*ports)
{
struct vcpu *v = current;
struct domain *d = v->domain;
- evtchn_port_t port = 0;
long rc;
unsigned int i;
- /* Fairly arbitrary limit. */
- if ( sched_poll->nr_ports > 128 )
- return -EINVAL;
-
- if ( !guest_handle_okay(sched_poll->ports, sched_poll->nr_ports) )
- return -EFAULT;
-
set_bit(_VPF_blocked, &v->pause_flags);
v->poll_evtchn = -1;
set_bit(v->vcpu_id, d->poll_mask);
@@ -1478,13 +1470,9 @@ static long do_poll(const struct sched_poll *sched_poll)
if ( local_events_need_delivery() )
goto out;
- for ( i = 0; i < sched_poll->nr_ports; i++ )
+ for ( i = 0; i < nr_ports; i++ )
{
- rc = -EFAULT;
- if ( __copy_from_guest_offset(&port, sched_poll->ports, i, 1) )
- goto out;
-
- rc = evtchn_port_poll(d, port);
+ rc = evtchn_port_poll(d, ports[i]);
if ( rc )
{
if ( rc > 0 )
@@ -1493,11 +1481,11 @@ static long do_poll(const struct sched_poll *sched_poll)
}
}
- if ( sched_poll->nr_ports == 1 )
- v->poll_evtchn = port;
+ if ( nr_ports == 1 )
+ v->poll_evtchn = ports[0];
- if ( sched_poll->timeout != 0 )
- set_timer(&v->poll_timer, sched_poll->timeout);
+ if ( timeout != 0 )
+ set_timer(&v->poll_timer, timeout);
TRACE_TIME(TRC_SCHED_BLOCK, d->domain_id, v->vcpu_id);
raise_softirq(SCHEDULE_SOFTIRQ);
@@ -1511,6 +1499,20 @@ static long do_poll(const struct sched_poll *sched_poll)
return rc;
}
+static long do_poll(struct sched_poll *sched_poll)
+{
+ evtchn_port_t ports[128];
+
+ /* Fairly arbitrary limit */
+ if ( sched_poll->nr_ports > 128 )
+ return -EINVAL;
+
+ if ( copy_from_guest(ports, sched_poll->ports, sched_poll->nr_ports) )
+ return -EFAULT;
+
+ return vcpu_poll(sched_poll->nr_ports, sched_poll->timeout, ports);
+}
+
/* Voluntarily yield the processor for this allocation. */
long vcpu_yield(void)
{
--
2.50.1
Teddy Astie | Vates XCP-ng Developer
XCP-ng & Xen Orchestra - Vates solutions
web: https://vates.tech
