[031/151] KVM: s390: Make psw available on all exits, not just a subset

Greg KH
2009-12-17T04:42:55Z

From: Carsten Otte <carsteno@de.ibm.com>

commit d7b0b5eb3000c6fb902f08c619fcd673a23d8fab upstream.

This patch moves s390 processor status word into the base kvm_run
struct and keeps it up-to date on all userspace exits.

The userspace ABI is broken by this, however there are no applications
in the wild using this. A capability check is provided so users can
verify the updated API exists.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
arch/s390/include/asm/kvm.h | 3 ++-
arch/s390/kvm/kvm-s390.c | 25 +++++++++++++++++--------
include/linux/kvm.h | 8 ++++++--
3 files changed, 25 insertions(+), 11 deletions(-)

--- a/arch/s390/include/asm/kvm.h
+++ b/arch/s390/include/asm/kvm.h
@@ -1,6 +1,5 @@
#ifndef __LINUX_KVM_S390_H
#define __LINUX_KVM_S390_H
-
/*
* asm-s390/kvm.h - KVM s390 specific structures and definitions
*
@@ -15,6 +14,8 @@
*/
#include <linux/types.h>

+#define __KVM_S390
+
/* for KVM_GET_REGS and KVM_SET_REGS */
struct kvm_regs {
/* general purpose regs for s390 */
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -116,10 +116,16 @@ long kvm_arch_dev_ioctl(struct file *fil

int kvm_dev_ioctl_check_extension(long ext)
{
+ int r;
+
switch (ext) {
+ case KVM_CAP_S390_PSW:
+ r = 1;
+ break;
default:
- return 0;
+ r = 0;
}
+ return r;
}

/* Section: vm related */
@@ -419,8 +425,10 @@ static int kvm_arch_vcpu_ioctl_set_initi
vcpu_load(vcpu);
if (atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_RUNNING)
rc = -EBUSY;
- else
- vcpu->arch.sie_block->gpsw = psw;
+ else {
+ vcpu->run->psw_mask = psw.mask;
+ vcpu->run->psw_addr = psw.addr;
+ }
vcpu_put(vcpu);
return rc;
}
@@ -508,9 +516,6 @@ rerun_vcpu:

switch (kvm_run->exit_reason) {
case KVM_EXIT_S390_SIEIC:
- vcpu->arch.sie_block->gpsw.mask = kvm_run->s390_sieic.mask;
- vcpu->arch.sie_block->gpsw.addr = kvm_run->s390_sieic.addr;
- break;
case KVM_EXIT_UNKNOWN:
case KVM_EXIT_INTR:
case KVM_EXIT_S390_RESET:
@@ -519,6 +524,9 @@ rerun_vcpu:
BUG();
}

+ vcpu->arch.sie_block->gpsw.mask = kvm_run->psw_mask;
+ vcpu->arch.sie_block->gpsw.addr = kvm_run->psw_addr;
+
might_fault();

do {
@@ -538,8 +546,6 @@ rerun_vcpu:
/* intercept cannot be handled in-kernel, prepare kvm-run */
kvm_run->exit_reason = KVM_EXIT_S390_SIEIC;
kvm_run->s390_sieic.icptcode = vcpu->arch.sie_block->icptcode;
- kvm_run->s390_sieic.mask = vcpu->arch.sie_block->gpsw.mask;
- kvm_run->s390_sieic.addr = vcpu->arch.sie_block->gpsw.addr;
kvm_run->s390_sieic.ipa = vcpu->arch.sie_block->ipa;
kvm_run->s390_sieic.ipb = vcpu->arch.sie_block->ipb;
rc = 0;
@@ -551,6 +557,9 @@ rerun_vcpu:
rc = 0;
}

+ kvm_run->psw_mask = vcpu->arch.sie_block->gpsw.mask;
+ kvm_run->psw_addr = vcpu->arch.sie_block->gpsw.addr;
+
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &sigsaved, NULL);

--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -116,6 +116,11 @@ struct kvm_run {
__u64 cr8;
__u64 apic_base;

+#ifdef __KVM_S390
+ /* the processor status word for s390 */
+ __u64 psw_mask; /* psw upper half */
+ __u64 psw_addr; /* psw lower half */
+#endif
union {
/* KVM_EXIT_UNKNOWN */
struct {
@@ -167,8 +172,6 @@ struct kvm_run {
/* KVM_EXIT_S390_SIEIC */
struct {
__u8 icptcode;
- __u64 mask; /* psw upper half */
- __u64 addr; /* psw lower half */
__u16 ipa;
__u32 ipb;
} s390_sieic;
@@ -474,6 +477,7 @@ struct kvm_irq_routing {
};

#endif
+#define KVM_CAP_S390_PSW 42

#ifdef KVM_CAP_MCE
/* x86 MCE */