1 files changed, 97 insertions, 0 deletions
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
new file mode 100644
index 00000000..a353f0ea
--- /dev/null
+++ b/arch/s390/kvm/diag.c
@@ -0,0 +1,97 @@
+/*
+ * diag.c - handling diagnose instructions
+ *
+ * Copyright IBM Corp. 2008,2011
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ *    Author(s): Carsten Otte <cotte@de.ibm.com>
+ *               Christian Borntraeger <borntraeger@de.ibm.com>
+ */
+
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include "kvm-s390.h"
+
+static int diag_release_pages(struct kvm_vcpu *vcpu)
+{
+	unsigned long start, end;
+	unsigned long prefix  = vcpu->arch.sie_block->prefix;
+
+	start = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
+	end = vcpu->run->s.regs.gprs[vcpu->arch.sie_block->ipa & 0xf] + 4096;
+
+	if (start & ~PAGE_MASK || end & ~PAGE_MASK || start > end
+	    || start < 2 * PAGE_SIZE)
+		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+	VCPU_EVENT(vcpu, 5, "diag release pages %lX %lX", start, end);
+	vcpu->stat.diagnose_10++;
+
+	/* we checked for start > end above */
+	if (end < prefix || start >= prefix + 2 * PAGE_SIZE) {
+		gmap_discard(start, end, vcpu->arch.gmap);
+	} else {
+		if (start < prefix)
+			gmap_discard(start, prefix, vcpu->arch.gmap);
+		if (end >= prefix)
+			gmap_discard(prefix + 2 * PAGE_SIZE,
+				     end, vcpu->arch.gmap);
+	}
+	return 0;
+}
+
+static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
+{
+	VCPU_EVENT(vcpu, 5, "%s", "diag time slice end");
+	vcpu->stat.diagnose_44++;
+	vcpu_put(vcpu);
+	yield();
+	vcpu_load(vcpu);
+	return 0;
+}
+
+static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
+{
+	unsigned int reg = vcpu->arch.sie_block->ipa & 0xf;
+	unsigned long subcode = vcpu->run->s.regs.gprs[reg] & 0xffff;
+
+	VCPU_EVENT(vcpu, 5, "diag ipl functions, subcode %lx", subcode);
+	switch (subcode) {
+	case 3:
+		vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR;
+		break;
+	case 4:
+		vcpu->run->s390_reset_flags = 0;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
+	vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM;
+	vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL;
+	vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT;
+	vcpu->run->exit_reason = KVM_EXIT_S390_RESET;
+	VCPU_EVENT(vcpu, 3, "requesting userspace resets %llx",
+	  vcpu->run->s390_reset_flags);
+	return -EREMOTE;
+}
+
+int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
+{
+	int code = (vcpu->arch.sie_block->ipb & 0xfff0000) >> 16;
+
+	switch (code) {
+	case 0x10:
+		return diag_release_pages(vcpu);
+	case 0x44:
+		return __diag_time_slice_end(vcpu);
+	case 0x308:
+		return __diag_ipl_functions(vcpu);
+	default:
+		return -EOPNOTSUPP;
+	}
+}