arch/s390/kvm/diag.c

   1 /*
   2  * 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 #include "trace.h"
  18 #include "trace-s390.h"
  19
  20 static int diag_release_pages(struct kvm_vcpu *vcpu)
  21 {
  22         unsigned long start, end;
  23         unsigned long prefix  = vcpu->arch.sie_block->prefix;
  24
  25         start = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
  26         end = vcpu->run->s.regs.gprs[vcpu->arch.sie_block->ipa & 0xf] + 4096;
  27
  28         if (start & ~PAGE_MASK || end & ~PAGE_MASK || start > end
  29             || start < 2 * PAGE_SIZE)
  30                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
  31
  32         VCPU_EVENT(vcpu, 5, "diag release pages %lX %lX", start, end);
  33         vcpu->stat.diagnose_10++;
  34
  35         /* we checked for start > end above */
  36         if (end < prefix || start >= prefix + 2 * PAGE_SIZE) {
  37                 gmap_discard(start, end, vcpu->arch.gmap);
  38         } else {
  39                 if (start < prefix)
  40                         gmap_discard(start, prefix, vcpu->arch.gmap);
  41                 if (end >= prefix)
  42                         gmap_discard(prefix + 2 * PAGE_SIZE,
  43                                      end, vcpu->arch.gmap);
  44         }
  45         return 0;
  46 }
  47
  48 static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
  49 {
  50         VCPU_EVENT(vcpu, 5, "%s", "diag time slice end");
  51         vcpu->stat.diagnose_44++;
  52         kvm_vcpu_on_spin(vcpu);
  53         return 0;
  54 }
  55
  56 static int __diag_time_slice_end_directed(struct kvm_vcpu *vcpu)
  57 {
  58         struct kvm *kvm = vcpu->kvm;
  59         struct kvm_vcpu *tcpu;
  60         int tid;
  61         int i;
  62
  63         tid = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
  64         vcpu->stat.diagnose_9c++;
  65         VCPU_EVENT(vcpu, 5, "diag time slice end directed to %d", tid);
  66
  67         if (tid == vcpu->vcpu_id)
  68                 return 0;
  69
  70         kvm_for_each_vcpu(i, tcpu, kvm)
  71                 if (tcpu->vcpu_id == tid) {
  72                         kvm_vcpu_yield_to(tcpu);
  73                         break;
  74                 }
  75
  76         return 0;
  77 }
  78
  79 static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
  80 {
  81         unsigned int reg = vcpu->arch.sie_block->ipa & 0xf;
  82         unsigned long subcode = vcpu->run->s.regs.gprs[reg] & 0xffff;
  83
  84         VCPU_EVENT(vcpu, 5, "diag ipl functions, subcode %lx", subcode);
  85         switch (subcode) {
  86         case 3:
  87                 vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR;
  88                 break;
  89         case 4:
  90                 vcpu->run->s390_reset_flags = 0;
  91                 break;
  92         default:
  93                 return -EOPNOTSUPP;
  94         }
  95
  96         atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
  97         vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM;
  98         vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL;
  99         vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT;
 100         vcpu->run->exit_reason = KVM_EXIT_S390_RESET;
 101         VCPU_EVENT(vcpu, 3, "requesting userspace resets %llx",
 102           vcpu->run->s390_reset_flags);
 103         trace_kvm_s390_request_resets(vcpu->run->s390_reset_flags);
 104         return -EREMOTE;
 105 }
 106
 107 int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
 108 {
 109         int code = (vcpu->arch.sie_block->ipb & 0xfff0000) >> 16;
 110
 111         trace_kvm_s390_handle_diag(vcpu, code);
 112         switch (code) {
 113         case 0x10:
 114                 return diag_release_pages(vcpu);
 115         case 0x44:
 116                 return __diag_time_slice_end(vcpu);
 117         case 0x9c:
 118                 return __diag_time_slice_end_directed(vcpu);
 119         case 0x308:
 120                 return __diag_ipl_functions(vcpu);
 121         default:
 122                 return -EOPNOTSUPP;
 123         }
 124 }