linux/arch/s390/kvm/priv.c
Christian Borntraeger ef50f7ac7e KVM: s390: Allow stfle instruction in the guest
2.6.31-rc introduced an architecture level set checker based on facility
bits. e.g. if the kernel is compiled to run only on z9, several facility
bits are checked very early and the kernel refuses to boot if a z9 specific
facility is missing.
Until now kvm on s390 did not implement the store facility extended (STFLE)
instruction. A 2.6.31-rc kernel that was compiled for z9 or higher did not
boot in kvm. This patch implements stfle.

This patch should go in before 2.6.31.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-28 14:10:30 +03:00

328 lines
8.0 KiB
C

/*
* priv.c - handling privileged instructions
*
* 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.h>
#include <linux/errno.h>
#include <asm/current.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include <asm/sysinfo.h>
#include "gaccess.h"
#include "kvm-s390.h"
static int handle_set_prefix(struct kvm_vcpu *vcpu)
{
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
u64 operand2;
u32 address = 0;
u8 tmp;
vcpu->stat.instruction_spx++;
operand2 = disp2;
if (base2)
operand2 += vcpu->arch.guest_gprs[base2];
/* must be word boundary */
if (operand2 & 3) {
kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
goto out;
}
/* get the value */
if (get_guest_u32(vcpu, operand2, &address)) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
goto out;
}
address = address & 0x7fffe000u;
/* make sure that the new value is valid memory */
if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
(copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1))) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
goto out;
}
vcpu->arch.sie_block->prefix = address;
vcpu->arch.sie_block->ihcpu = 0xffff;
VCPU_EVENT(vcpu, 5, "setting prefix to %x", address);
out:
return 0;
}
static int handle_store_prefix(struct kvm_vcpu *vcpu)
{
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
u64 operand2;
u32 address;
vcpu->stat.instruction_stpx++;
operand2 = disp2;
if (base2)
operand2 += vcpu->arch.guest_gprs[base2];
/* must be word boundary */
if (operand2 & 3) {
kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
goto out;
}
address = vcpu->arch.sie_block->prefix;
address = address & 0x7fffe000u;
/* get the value */
if (put_guest_u32(vcpu, operand2, address)) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
goto out;
}
VCPU_EVENT(vcpu, 5, "storing prefix to %x", address);
out:
return 0;
}
static int handle_store_cpu_address(struct kvm_vcpu *vcpu)
{
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
u64 useraddr;
int rc;
vcpu->stat.instruction_stap++;
useraddr = disp2;
if (base2)
useraddr += vcpu->arch.guest_gprs[base2];
if (useraddr & 1) {
kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
goto out;
}
rc = put_guest_u16(vcpu, useraddr, vcpu->vcpu_id);
if (rc == -EFAULT) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
goto out;
}
VCPU_EVENT(vcpu, 5, "storing cpu address to %llx", useraddr);
out:
return 0;
}
static int handle_skey(struct kvm_vcpu *vcpu)
{
vcpu->stat.instruction_storage_key++;
vcpu->arch.sie_block->gpsw.addr -= 4;
VCPU_EVENT(vcpu, 4, "%s", "retrying storage key operation");
return 0;
}
static int handle_stsch(struct kvm_vcpu *vcpu)
{
vcpu->stat.instruction_stsch++;
VCPU_EVENT(vcpu, 4, "%s", "store subchannel - CC3");
/* condition code 3 */
vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
vcpu->arch.sie_block->gpsw.mask |= (3 & 3ul) << 44;
return 0;
}
static int handle_chsc(struct kvm_vcpu *vcpu)
{
vcpu->stat.instruction_chsc++;
VCPU_EVENT(vcpu, 4, "%s", "channel subsystem call - CC3");
/* condition code 3 */
vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
vcpu->arch.sie_block->gpsw.mask |= (3 & 3ul) << 44;
return 0;
}
static int handle_stfl(struct kvm_vcpu *vcpu)
{
unsigned int facility_list = stfl();
int rc;
vcpu->stat.instruction_stfl++;
/* only pass the facility bits, which we can handle */
facility_list &= 0xff00fff3;
rc = copy_to_guest(vcpu, offsetof(struct _lowcore, stfl_fac_list),
&facility_list, sizeof(facility_list));
if (rc == -EFAULT)
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
else
VCPU_EVENT(vcpu, 5, "store facility list value %x",
facility_list);
return 0;
}
static int handle_stidp(struct kvm_vcpu *vcpu)
{
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
u64 operand2;
int rc;
vcpu->stat.instruction_stidp++;
operand2 = disp2;
if (base2)
operand2 += vcpu->arch.guest_gprs[base2];
if (operand2 & 7) {
kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
goto out;
}
rc = put_guest_u64(vcpu, operand2, vcpu->arch.stidp_data);
if (rc == -EFAULT) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
goto out;
}
VCPU_EVENT(vcpu, 5, "%s", "store cpu id");
out:
return 0;
}
static void handle_stsi_3_2_2(struct kvm_vcpu *vcpu, struct sysinfo_3_2_2 *mem)
{
struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
int cpus = 0;
int n;
spin_lock(&fi->lock);
for (n = 0; n < KVM_MAX_VCPUS; n++)
if (fi->local_int[n])
cpus++;
spin_unlock(&fi->lock);
/* deal with other level 3 hypervisors */
if (stsi(mem, 3, 2, 2) == -ENOSYS)
mem->count = 0;
if (mem->count < 8)
mem->count++;
for (n = mem->count - 1; n > 0 ; n--)
memcpy(&mem->vm[n], &mem->vm[n - 1], sizeof(mem->vm[0]));
mem->vm[0].cpus_total = cpus;
mem->vm[0].cpus_configured = cpus;
mem->vm[0].cpus_standby = 0;
mem->vm[0].cpus_reserved = 0;
mem->vm[0].caf = 1000;
memcpy(mem->vm[0].name, "KVMguest", 8);
ASCEBC(mem->vm[0].name, 8);
memcpy(mem->vm[0].cpi, "KVM/Linux ", 16);
ASCEBC(mem->vm[0].cpi, 16);
}
static int handle_stsi(struct kvm_vcpu *vcpu)
{
int fc = (vcpu->arch.guest_gprs[0] & 0xf0000000) >> 28;
int sel1 = vcpu->arch.guest_gprs[0] & 0xff;
int sel2 = vcpu->arch.guest_gprs[1] & 0xffff;
int base2 = vcpu->arch.sie_block->ipb >> 28;
int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
u64 operand2;
unsigned long mem;
vcpu->stat.instruction_stsi++;
VCPU_EVENT(vcpu, 4, "stsi: fc: %x sel1: %x sel2: %x", fc, sel1, sel2);
operand2 = disp2;
if (base2)
operand2 += vcpu->arch.guest_gprs[base2];
if (operand2 & 0xfff && fc > 0)
return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
switch (fc) {
case 0:
vcpu->arch.guest_gprs[0] = 3 << 28;
vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
return 0;
case 1: /* same handling for 1 and 2 */
case 2:
mem = get_zeroed_page(GFP_KERNEL);
if (!mem)
goto out_fail;
if (stsi((void *) mem, fc, sel1, sel2) == -ENOSYS)
goto out_mem;
break;
case 3:
if (sel1 != 2 || sel2 != 2)
goto out_fail;
mem = get_zeroed_page(GFP_KERNEL);
if (!mem)
goto out_fail;
handle_stsi_3_2_2(vcpu, (void *) mem);
break;
default:
goto out_fail;
}
if (copy_to_guest_absolute(vcpu, operand2, (void *) mem, PAGE_SIZE)) {
kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
goto out_mem;
}
free_page(mem);
vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
vcpu->arch.guest_gprs[0] = 0;
return 0;
out_mem:
free_page(mem);
out_fail:
/* condition code 3 */
vcpu->arch.sie_block->gpsw.mask |= 3ul << 44;
return 0;
}
static intercept_handler_t priv_handlers[256] = {
[0x02] = handle_stidp,
[0x10] = handle_set_prefix,
[0x11] = handle_store_prefix,
[0x12] = handle_store_cpu_address,
[0x29] = handle_skey,
[0x2a] = handle_skey,
[0x2b] = handle_skey,
[0x34] = handle_stsch,
[0x5f] = handle_chsc,
[0x7d] = handle_stsi,
[0xb1] = handle_stfl,
};
int kvm_s390_handle_b2(struct kvm_vcpu *vcpu)
{
intercept_handler_t handler;
/*
* a lot of B2 instructions are priviledged. We first check for
* the priviledges ones, that we can handle in the kernel. If the
* kernel can handle this instruction, we check for the problem
* state bit and (a) handle the instruction or (b) send a code 2
* program check.
* Anything else goes to userspace.*/
handler = priv_handlers[vcpu->arch.sie_block->ipa & 0x00ff];
if (handler) {
if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
return kvm_s390_inject_program_int(vcpu,
PGM_PRIVILEGED_OPERATION);
else
return handler(vcpu);
}
return -ENOTSUPP;
}