1 /*
2 * diag.c - handling diagnose instructions
3 *
4 * Copyright IBM Corp. 2008,2011
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License (version 2 only)
8 * as published by the Free Software Foundation.
9 *
10 * Author(s): Carsten Otte <cotte@de.ibm.com>
11 * Christian Borntraeger <borntraeger@de.ibm.com>
12 */
13
14 #include <linux/kvm.h>
15 #include <linux/kvm_host.h>
16 #include "kvm-s390.h"
17
diag_release_pages(struct kvm_vcpu * vcpu)18 static int diag_release_pages(struct kvm_vcpu *vcpu)
19 {
20 unsigned long start, end;
21 unsigned long prefix = vcpu->arch.sie_block->prefix;
22
23 start = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
24 end = vcpu->run->s.regs.gprs[vcpu->arch.sie_block->ipa & 0xf] + 4096;
25
26 if (start & ~PAGE_MASK || end & ~PAGE_MASK || start > end
27 || start < 2 * PAGE_SIZE)
28 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
29
30 VCPU_EVENT(vcpu, 5, "diag release pages %lX %lX", start, end);
31 vcpu->stat.diagnose_10++;
32
33 /* we checked for start > end above */
34 if (end < prefix || start >= prefix + 2 * PAGE_SIZE) {
35 gmap_discard(start, end, vcpu->arch.gmap);
36 } else {
37 if (start < prefix)
38 gmap_discard(start, prefix, vcpu->arch.gmap);
39 if (end >= prefix)
40 gmap_discard(prefix + 2 * PAGE_SIZE,
41 end, vcpu->arch.gmap);
42 }
43 return 0;
44 }
45
__diag_time_slice_end(struct kvm_vcpu * vcpu)46 static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
47 {
48 VCPU_EVENT(vcpu, 5, "%s", "diag time slice end");
49 vcpu->stat.diagnose_44++;
50 vcpu_put(vcpu);
51 yield();
52 vcpu_load(vcpu);
53 return 0;
54 }
55
__diag_ipl_functions(struct kvm_vcpu * vcpu)56 static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
57 {
58 unsigned int reg = vcpu->arch.sie_block->ipa & 0xf;
59 unsigned long subcode = vcpu->run->s.regs.gprs[reg] & 0xffff;
60
61 VCPU_EVENT(vcpu, 5, "diag ipl functions, subcode %lx", subcode);
62 switch (subcode) {
63 case 3:
64 vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR;
65 break;
66 case 4:
67 vcpu->run->s390_reset_flags = 0;
68 break;
69 default:
70 return -EOPNOTSUPP;
71 }
72
73 atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
74 vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM;
75 vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL;
76 vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT;
77 vcpu->run->exit_reason = KVM_EXIT_S390_RESET;
78 VCPU_EVENT(vcpu, 3, "requesting userspace resets %llx",
79 vcpu->run->s390_reset_flags);
80 return -EREMOTE;
81 }
82
kvm_s390_handle_diag(struct kvm_vcpu * vcpu)83 int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
84 {
85 int code = (vcpu->arch.sie_block->ipb & 0xfff0000) >> 16;
86
87 switch (code) {
88 case 0x10:
89 return diag_release_pages(vcpu);
90 case 0x44:
91 return __diag_time_slice_end(vcpu);
92 case 0x308:
93 return __diag_ipl_functions(vcpu);
94 default:
95 return -EOPNOTSUPP;
96 }
97 }
98