[v2,4/7] KVM: s390: provide query function for instructions returning 32 byte
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Message ID 20190424115619.2483-5-borntraeger@de.ibm.com
State New
Headers show
Series
  • KVM: s390: new guest facilities
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Commit Message

Christian Borntraeger April 24, 2019, 11:56 a.m. UTC
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@de.ibm.com>
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
---
 arch/s390/kvm/kvm-s390.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

Patch
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diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 0dad61ccde3d..336e591d94eb 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -321,6 +321,19 @@  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;