linux/arch/s390/kvm/intercept.c
Michael Mueller 7feb6bb8e6 KVM: s390: enable Transactional Execution
This patch enables transactional execution for KVM guests
on s390 systems zec12 or later.

We rework the allocation of the page containing the sie_block
to also back the Interception Transaction Diagnostic Block.
If available the TE facilities will be enabled.

Setting bit 73 and 50 in vfacilities bitmask reveals the HW
facilities Transactional Memory and Constraint Transactional
Memory respectively to the KVM guest.

Furthermore, the patch restores the Program-Interruption TDB
from the Interception TDB in case a program interception has
occurred and the ITDB has a valid format.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-01-17 13:12:01 +01:00

170 lines
4.3 KiB
C

/*
* in-kernel handling for sie intercepts
*
* Copyright IBM Corp. 2008, 2009
*
* 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"
#include "trace.h"
#include "trace-s390.h"
static const intercept_handler_t instruction_handlers[256] = {
[0x01] = kvm_s390_handle_01,
[0x82] = kvm_s390_handle_lpsw,
[0x83] = kvm_s390_handle_diag,
[0xae] = kvm_s390_handle_sigp,
[0xb2] = kvm_s390_handle_b2,
[0xb7] = kvm_s390_handle_lctl,
[0xb9] = kvm_s390_handle_b9,
[0xe5] = kvm_s390_handle_e5,
[0xeb] = kvm_s390_handle_eb,
};
static int handle_noop(struct kvm_vcpu *vcpu)
{
switch (vcpu->arch.sie_block->icptcode) {
case 0x0:
vcpu->stat.exit_null++;
break;
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 = 0;
vcpu->stat.exit_stop_request++;
spin_lock_bh(&vcpu->arch.local_int.lock);
trace_kvm_s390_stop_request(vcpu->arch.local_int.action_bits);
if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) {
atomic_set_mask(CPUSTAT_STOPPED,
&vcpu->arch.sie_block->cpuflags);
vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP;
VCPU_EVENT(vcpu, 3, "%s", "cpu stopped");
rc = -EOPNOTSUPP;
}
if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) {
vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP;
/* store status must be called unlocked. Since local_int.lock
* only protects local_int.* and not guest memory we can give
* up the lock here */
spin_unlock_bh(&vcpu->arch.local_int.lock);
rc = kvm_s390_vcpu_store_status(vcpu,
KVM_S390_STORE_STATUS_NOADDR);
if (rc >= 0)
rc = -EOPNOTSUPP;
} else
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++;
trace_kvm_s390_intercept_validity(vcpu, viwhy);
WARN_ONCE(true, "kvm: unhandled validity intercept 0x%x\n", viwhy);
return -EOPNOTSUPP;
}
static int handle_instruction(struct kvm_vcpu *vcpu)
{
intercept_handler_t handler;
vcpu->stat.exit_instruction++;
trace_kvm_s390_intercept_instruction(vcpu,
vcpu->arch.sie_block->ipa,
vcpu->arch.sie_block->ipb);
handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8];
if (handler)
return handler(vcpu);
return -EOPNOTSUPP;
}
static int handle_prog(struct kvm_vcpu *vcpu)
{
vcpu->stat.exit_program_interruption++;
/* Restore ITDB to Program-Interruption TDB in guest memory */
if (IS_TE_ENABLED(vcpu) &&
!(current->thread.per_flags & PER_FLAG_NO_TE) &&
IS_ITDB_VALID(vcpu)) {
copy_to_guest(vcpu, TDB_ADDR, vcpu->arch.sie_block->itdba,
sizeof(struct kvm_s390_itdb));
memset((void *) vcpu->arch.sie_block->itdba, 0,
sizeof(struct kvm_s390_itdb));
}
trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
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 == -EOPNOTSUPP)
vcpu->arch.sie_block->icptcode = 0x04;
if (rc)
return rc;
return rc2;
}
static const intercept_handler_t intercept_funcs[] = {
[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,
[0x18 >> 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 >> 2) >= ARRAY_SIZE(intercept_funcs))
return -EOPNOTSUPP;
func = intercept_funcs[code >> 2];
if (func)
return func(vcpu);
return -EOPNOTSUPP;
}