[SRU][B][D][Patch 6/9] KVM: s390: provide query function for instructions returning 32 byte

[frank.heimes at canonical.com]

From: Christian Borntraeger <borntraeger at de.ibm.com>

BugLink: https://bugs.launchpad.net/bugs/1836153

Some of the new features have a 32byte response for the query function.
Provide a new wrapper similar to __cpacf_query. We might want to factor
this out if other users come up, as of today there is none. So let us
keep the function within KVM.

Signed-off-by: Christian Borntraeger <borntraeger at de.ibm.com>
Reviewed-by: Collin Walling <walling at linux.ibm.com>
Reviewed-by: David Hildenbrand <david at redhat.com>
(cherry picked from commit d668139718a9e2260702777bd8d86d71c30b6539)
Signed-off-by: Frank Heimes <frank.heimes at canonical.com>
---
 arch/s390/kvm/kvm-s390.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 0dbb31b..995d229 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -297,6 +297,19 @@ static inline int plo_test_bit(unsigned char nr)
 	return cc == 0;
 }
 
+static inline void __insn32_query(unsigned int opcode, u8 query[32])
+{
+	register unsigned long r0 asm("0") = 0;	/* query function */
+	register unsigned long r1 asm("1") = (unsigned long) query;
+
+	asm volatile(
+		/* Parameter regs are ignored */
+		"	.insn	rrf,%[opc] << 16,2,4,6,0\n"
+		: "=m" (*query)
+		: "d" (r0), "a" (r1), [opc] "i" (opcode)
+		: "cc");
+}
+
 static void kvm_s390_cpu_feat_init(void)
 {
 	int i;
-- 
2.7.4