android_kernel_motorola_sm6225/arch/s390/kvm/intercept.c
Christian Borntraeger e28acfea5d KVM: s390: intercepts for diagnose instructions
This patch introduces interpretation of some diagnose instruction intercepts.
Diagnose is our classic architected way of doing a hypercall. This patch
features the following diagnose codes:
- vm storage size, that tells the guest about its memory layout
- time slice end, which is used by the guest to indicate that it waits
  for a lock and thus cannot use up its time slice in a useful way
- ipl functions, which a guest can use to reset and reboot itself

In order to implement ipl functions, we also introduce an exit reason that
causes userspace to perform various resets on the virtual machine. All resets
are described in the principles of operation book, except KVM_S390_RESET_IPL
which causes a reboot of the machine.

Acked-by: Martin Schwidefsky <martin.schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:00:46 +03:00

216 lines
5.1 KiB
C

/*
* intercept.c - in-kernel handling for sie intercepts
*
* Copyright IBM Corp. 2008
*
* 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_host.h>
#include <linux/errno.h>
#include <linux/pagemap.h>
#include <asm/kvm_host.h>
#include "kvm-s390.h"
#include "gaccess.h"
static int handle_lctg(struct kvm_vcpu *vcpu)
{
int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16) +
((vcpu->arch.sie_block->ipb & 0xff00) << 4);
u64 useraddr;
int reg, rc;
vcpu->stat.instruction_lctg++;
if ((vcpu->arch.sie_block->ipb & 0xff) != 0x2f)
return -ENOTSUPP;
useraddr = disp2;
if (base2)
useraddr += vcpu->arch.guest_gprs[base2];
reg = reg1;
VCPU_EVENT(vcpu, 5, "lctg r1:%x, r3:%x,b2:%x,d2:%x", reg1, reg3, base2,
disp2);
do {
rc = get_guest_u64(vcpu, useraddr,
&vcpu->arch.sie_block->gcr[reg]);
if (rc == -EFAULT) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
break;
}
useraddr += 8;
if (reg == reg3)
break;
reg = (reg + 1) % 16;
} while (1);
return 0;
}
static int handle_lctl(struct kvm_vcpu *vcpu)
{
int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
u64 useraddr;
u32 val = 0;
int reg, rc;
vcpu->stat.instruction_lctl++;
useraddr = disp2;
if (base2)
useraddr += vcpu->arch.guest_gprs[base2];
VCPU_EVENT(vcpu, 5, "lctl r1:%x, r3:%x,b2:%x,d2:%x", reg1, reg3, base2,
disp2);
reg = reg1;
do {
rc = get_guest_u32(vcpu, useraddr, &val);
if (rc == -EFAULT) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
break;
}
vcpu->arch.sie_block->gcr[reg] &= 0xffffffff00000000ul;
vcpu->arch.sie_block->gcr[reg] |= val;
useraddr += 4;
if (reg == reg3)
break;
reg = (reg + 1) % 16;
} while (1);
return 0;
}
static intercept_handler_t instruction_handlers[256] = {
[0x83] = kvm_s390_handle_diag,
[0xae] = kvm_s390_handle_sigp,
[0xb2] = kvm_s390_handle_priv,
[0xb7] = handle_lctl,
[0xeb] = handle_lctg,
};
static int handle_noop(struct kvm_vcpu *vcpu)
{
switch (vcpu->arch.sie_block->icptcode) {
case 0x10:
vcpu->stat.exit_external_request++;
break;
case 0x14:
vcpu->stat.exit_external_interrupt++;
break;
default:
break; /* nothing */
}
return 0;
}
static int handle_stop(struct kvm_vcpu *vcpu)
{
int rc;
vcpu->stat.exit_stop_request++;
atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
spin_lock_bh(&vcpu->arch.local_int.lock);
if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) {
vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP;
rc = __kvm_s390_vcpu_store_status(vcpu,
KVM_S390_STORE_STATUS_NOADDR);
if (rc >= 0)
rc = -ENOTSUPP;
}
if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) {
vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP;
VCPU_EVENT(vcpu, 3, "%s", "cpu stopped");
rc = -ENOTSUPP;
} else
rc = 0;
spin_unlock_bh(&vcpu->arch.local_int.lock);
return rc;
}
static int handle_validity(struct kvm_vcpu *vcpu)
{
int viwhy = vcpu->arch.sie_block->ipb >> 16;
vcpu->stat.exit_validity++;
if (viwhy == 0x37) {
fault_in_pages_writeable((char __user *)
vcpu->kvm->arch.guest_origin +
vcpu->arch.sie_block->prefix,
PAGE_SIZE);
return 0;
}
VCPU_EVENT(vcpu, 2, "unhandled validity intercept code %d",
viwhy);
return -ENOTSUPP;
}
static int handle_instruction(struct kvm_vcpu *vcpu)
{
intercept_handler_t handler;
vcpu->stat.exit_instruction++;
handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8];
if (handler)
return handler(vcpu);
return -ENOTSUPP;
}
static int handle_prog(struct kvm_vcpu *vcpu)
{
vcpu->stat.exit_program_interruption++;
return kvm_s390_inject_program_int(vcpu, vcpu->arch.sie_block->iprcc);
}
static int handle_instruction_and_prog(struct kvm_vcpu *vcpu)
{
int rc, rc2;
vcpu->stat.exit_instr_and_program++;
rc = handle_instruction(vcpu);
rc2 = handle_prog(vcpu);
if (rc == -ENOTSUPP)
vcpu->arch.sie_block->icptcode = 0x04;
if (rc)
return rc;
return rc2;
}
static const intercept_handler_t intercept_funcs[0x48 >> 2] = {
[0x00 >> 2] = handle_noop,
[0x04 >> 2] = handle_instruction,
[0x08 >> 2] = handle_prog,
[0x0C >> 2] = handle_instruction_and_prog,
[0x10 >> 2] = handle_noop,
[0x14 >> 2] = handle_noop,
[0x1C >> 2] = kvm_s390_handle_wait,
[0x20 >> 2] = handle_validity,
[0x28 >> 2] = handle_stop,
};
int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
{
intercept_handler_t func;
u8 code = vcpu->arch.sie_block->icptcode;
if (code & 3 || code > 0x48)
return -ENOTSUPP;
func = intercept_funcs[code >> 2];
if (func)
return func(vcpu);
return -ENOTSUPP;
}