From 1a3b2b87de3458c31272f39401ec7bda0b6fd531 Mon Sep 17 00:00:00 2001
From: Colin Percival <cperciva@FreeBSD.org>
Date: Thu, 25 Nov 2010 15:05:21 +0000
Subject: [PATCH] Rename HYPERVISOR_multicall (which performs the multicall
 hypercall) to _HYPERVISOR_multicall, and create a new HYPERVISOR_multicall
 function which invokes _HYPERVISOR_multicall and checks that the individual
 hypercalls all succeeded.

---
 sys/i386/include/xen/hypercall.h |  3 ++-
 sys/i386/xen/xen_machdep.c       | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/sys/i386/include/xen/hypercall.h b/sys/i386/include/xen/hypercall.h
index b33626f7c7e7..2631a9b58e6f 100644
--- a/sys/i386/include/xen/hypercall.h
+++ b/sys/i386/include/xen/hypercall.h
@@ -234,8 +234,9 @@ HYPERVISOR_memory_op(
 	return _hypercall2(int, memory_op, cmd, arg);
 }
 
+int HYPERVISOR_multicall(multicall_entry_t *, int);
 static inline int
-HYPERVISOR_multicall(
+_HYPERVISOR_multicall(
 	void *call_list, int nr_calls)
 {
 	return _hypercall2(int, multicall, call_list, nr_calls);
diff --git a/sys/i386/xen/xen_machdep.c b/sys/i386/xen/xen_machdep.c
index 2d46f6eeef50..a9180fc3b3e0 100644
--- a/sys/i386/xen/xen_machdep.c
+++ b/sys/i386/xen/xen_machdep.c
@@ -1177,6 +1177,27 @@ trap_info_t trap_table[] = {
 	{  0, 0,           0, 0 }
 };
 
+/* Perform a multicall and check that individual calls succeeded. */
+int
+HYPERVISOR_multicall(struct multicall_entry * call_list, int nr_calls)
+{
+	int ret = 0;
+	int i;
+
+	/* Perform the multicall. */
+	PANIC_IF(_HYPERVISOR_multicall(call_list, nr_calls));
+
+	/* Check the results of individual hypercalls. */
+	for (i = 0; i < nr_calls; i++)
+		if (unlikely(call_list[i].result < 0))
+			ret++;
+	if (unlikely(ret > 0))
+		panic("%d multicall(s) failed: cpu %d\n",
+		    ret, smp_processor_id());
+
+	/* If we didn't panic already, everything succeeded. */
+	return (0);
+}
 
 /********** CODE WORTH KEEPING ABOVE HERE *****************/