When the host supports the CPU topology facility, the PTF
instruction with function code 2 is interpreted by the SIE,
provided that the userland hypervizor activates the interpretation
by using the KVM_CAP_S390_CPU_TOPOLOGY KVM extension.
The PTF instructions with function code 0 and 1 are intercepted
and must be emulated by the userland hypervizor.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
hw/s390x/cpu-topology.c | 52 ++++++++++++++++++++++++++++++
include/hw/s390x/s390-virtio-ccw.h | 6 ++++
target/s390x/kvm/kvm.c | 13 ++++++++
3 files changed, 71 insertions(+)
diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
index b6bf839e40..7dcaa28ca3 100644
--- a/hw/s390x/cpu-topology.c
+++ b/hw/s390x/cpu-topology.c
@@ -20,6 +20,58 @@
#include "hw/s390x/s390-virtio-ccw.h"
#include "hw/s390x/cpu-topology.h"
#include "migration/vmstate.h"
+#include "target/s390x/cpu.h"
+#include "hw/s390x/s390-virtio-ccw.h"
+
+/*
+ * s390_handle_ptf:
+ *
+ * @register 1: contains the function code
+ *
+ * Function codes 0 and 1 handle the CPU polarization.
+ * We assume an horizontal topology, the only one supported currently
+ * by Linux, consequently we answer to function code 0, requesting
+ * horizontal polarization that it is already the current polarization
+ * and reject vertical polarization request without further explanation.
+ *
+ * Function code 2 is handling topology changes and is interpreted
+ * by the SIE.
+ */
+void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra)
+{
+ CPUS390XState *env = &cpu->env;
+ uint64_t reg = env->regs[r1];
+ uint8_t fc = reg & S390_TOPO_FC_MASK;
+
+ if (!s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY)) {
+ s390_program_interrupt(env, PGM_OPERATION, ra);
+ return;
+ }
+
+ if (env->psw.mask & PSW_MASK_PSTATE) {
+ s390_program_interrupt(env, PGM_PRIVILEGED, ra);
+ return;
+ }
+
+ if (reg & ~S390_TOPO_FC_MASK) {
+ s390_program_interrupt(env, PGM_SPECIFICATION, ra);
+ return;
+ }
+
+ switch (fc) {
+ case 0: /* Horizontal polarization is already set */
+ env->regs[r1] |= S390_PTF_REASON_DONE;
+ setcc(cpu, 2);
+ break;
+ case 1: /* Vertical polarization is not supported */
+ env->regs[r1] |= S390_PTF_REASON_NONE;
+ setcc(cpu, 2);
+ break;
+ default:
+ /* Note that fc == 2 is interpreted by the SIE */
+ s390_program_interrupt(env, PGM_SPECIFICATION, ra);
+ }
+}
S390Topology *s390_get_topology(void)
{
diff --git a/include/hw/s390x/s390-virtio-ccw.h b/include/hw/s390x/s390-virtio-ccw.h
index 8a0090a071..9e7a0d75bc 100644
--- a/include/hw/s390x/s390-virtio-ccw.h
+++ b/include/hw/s390x/s390-virtio-ccw.h
@@ -31,6 +31,12 @@ struct S390CcwMachineState {
uint8_t loadparm[8];
};
+#define S390_PTF_REASON_NONE (0x00 << 8)
+#define S390_PTF_REASON_DONE (0x01 << 8)
+#define S390_PTF_REASON_BUSY (0x02 << 8)
+#define S390_TOPO_FC_MASK 0xffUL
+void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra);
+
struct S390CcwMachineClass {
/*< private >*/
MachineClass parent_class;
diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c
index 9c994d27d5..cb14bcc012 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -97,6 +97,7 @@
#define PRIV_B9_EQBS 0x9c
#define PRIV_B9_CLP 0xa0
+#define PRIV_B9_PTF 0xa2
#define PRIV_B9_PCISTG 0xd0
#define PRIV_B9_PCILG 0xd2
#define PRIV_B9_RPCIT 0xd3
@@ -1463,6 +1464,15 @@ static int kvm_mpcifc_service_call(S390CPU *cpu, struct kvm_run *run)
}
}
+static int kvm_handle_ptf(S390CPU *cpu, struct kvm_run *run)
+{
+ uint8_t r1 = (run->s390_sieic.ipb >> 20) & 0x0f;
+
+ s390_handle_ptf(cpu, r1, RA_IGNORED);
+
+ return 0;
+}
+
static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
{
int r = 0;
@@ -1480,6 +1490,9 @@ static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
case PRIV_B9_RPCIT:
r = kvm_rpcit_service_call(cpu, run);
break;
+ case PRIV_B9_PTF:
+ r = kvm_handle_ptf(cpu, run);
+ break;
case PRIV_B9_EQBS:
/* just inject exception */
r = -1;
--
2.31.1On Fri, 2022-09-02 at 09:55 +0200, Pierre Morel wrote:
> When the host supports the CPU topology facility, the PTF
> instruction with function code 2 is interpreted by the SIE,
> provided that the userland hypervizor activates the interpretation
> by using the KVM_CAP_S390_CPU_TOPOLOGY KVM extension.
>
> The PTF instructions with function code 0 and 1 are intercepted
> and must be emulated by the userland hypervizor.
>
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
See note below.
> ---
> hw/s390x/cpu-topology.c | 52 ++++++++++++++++++++++++++++++
> include/hw/s390x/s390-virtio-ccw.h | 6 ++++
> target/s390x/kvm/kvm.c | 13 ++++++++
> 3 files changed, 71 insertions(+)
>
> diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
> index b6bf839e40..7dcaa28ca3 100644
> --- a/hw/s390x/cpu-topology.c
> +++ b/hw/s390x/cpu-topology.c
> @@ -20,6 +20,58 @@
> #include "hw/s390x/s390-virtio-ccw.h"
> #include "hw/s390x/cpu-topology.h"
> #include "migration/vmstate.h"
> +#include "target/s390x/cpu.h"
> +#include "hw/s390x/s390-virtio-ccw.h"
> +
> +/*
> + * s390_handle_ptf:
> + *
> + * @register 1: contains the function code
> + *
> + * Function codes 0 and 1 handle the CPU polarization.
> + * We assume an horizontal topology, the only one supported currently
> + * by Linux, consequently we answer to function code 0, requesting
> + * horizontal polarization that it is already the current polarization
> + * and reject vertical polarization request without further explanation.
> + *
> + * Function code 2 is handling topology changes and is interpreted
> + * by the SIE.
> + */
> +void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra)
> +{
> + CPUS390XState *env = &cpu->env;
> + uint64_t reg = env->regs[r1];
> + uint8_t fc = reg & S390_TOPO_FC_MASK;
> +
> + if (!s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY)) {
> + s390_program_interrupt(env, PGM_OPERATION, ra);
> + return;
I'm either expecting this function to return -1 here...
> + }
> +
> + if (env->psw.mask & PSW_MASK_PSTATE) {
> + s390_program_interrupt(env, PGM_PRIVILEGED, ra);
> + return;
> + }
> +
> + if (reg & ~S390_TOPO_FC_MASK) {
> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
> + return;
> + }
> +
> + switch (fc) {
> + case 0: /* Horizontal polarization is already set */
> + env->regs[r1] |= S390_PTF_REASON_DONE;
> + setcc(cpu, 2);
> + break;
> + case 1: /* Vertical polarization is not supported */
> + env->regs[r1] |= S390_PTF_REASON_NONE;
> + setcc(cpu, 2);
> + break;
> + default:
> + /* Note that fc == 2 is interpreted by the SIE */
> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
> + }
> +}
[...]
>
> +static int kvm_handle_ptf(S390CPU *cpu, struct kvm_run *run)
> +{
> + uint8_t r1 = (run->s390_sieic.ipb >> 20) & 0x0f;
> +
> + s390_handle_ptf(cpu, r1, RA_IGNORED);
... and this being returned here...
> +
> + return 0;
... or this function being void.
> +}
> +
> static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
> {
> int r = 0;
> @@ -1480,6 +1490,9 @@ static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
> case PRIV_B9_RPCIT:
> r = kvm_rpcit_service_call(cpu, run);
> break;
> + case PRIV_B9_PTF:
> + r = kvm_handle_ptf(cpu, run);
> + break;
> case PRIV_B9_EQBS:
> /* just inject exception */
> r = -1;
On 9/9/22 18:50, Janis Schoetterl-Glausch wrote:
> On Fri, 2022-09-02 at 09:55 +0200, Pierre Morel wrote:
>> When the host supports the CPU topology facility, the PTF
>> instruction with function code 2 is interpreted by the SIE,
>> provided that the userland hypervizor activates the interpretation
>> by using the KVM_CAP_S390_CPU_TOPOLOGY KVM extension.
>>
>> The PTF instructions with function code 0 and 1 are intercepted
>> and must be emulated by the userland hypervizor.
>>
>> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
>
> Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Thanks
>
> See note below.
>> ---
>> hw/s390x/cpu-topology.c | 52 ++++++++++++++++++++++++++++++
>> include/hw/s390x/s390-virtio-ccw.h | 6 ++++
>> target/s390x/kvm/kvm.c | 13 ++++++++
>> 3 files changed, 71 insertions(+)
>>
>> diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
>> index b6bf839e40..7dcaa28ca3 100644
>> --- a/hw/s390x/cpu-topology.c
>> +++ b/hw/s390x/cpu-topology.c
>> @@ -20,6 +20,58 @@
>> #include "hw/s390x/s390-virtio-ccw.h"
>> #include "hw/s390x/cpu-topology.h"
>> #include "migration/vmstate.h"
>> +#include "target/s390x/cpu.h"
>> +#include "hw/s390x/s390-virtio-ccw.h"
>> +
>> +/*
>> + * s390_handle_ptf:
>> + *
>> + * @register 1: contains the function code
>> + *
>> + * Function codes 0 and 1 handle the CPU polarization.
>> + * We assume an horizontal topology, the only one supported currently
>> + * by Linux, consequently we answer to function code 0, requesting
>> + * horizontal polarization that it is already the current polarization
>> + * and reject vertical polarization request without further explanation.
>> + *
>> + * Function code 2 is handling topology changes and is interpreted
>> + * by the SIE.
>> + */
>> +void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra)
>> +{
>> + CPUS390XState *env = &cpu->env;
>> + uint64_t reg = env->regs[r1];
>> + uint8_t fc = reg & S390_TOPO_FC_MASK;
>> +
>> + if (!s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY)) {
>> + s390_program_interrupt(env, PGM_OPERATION, ra);
>> + return;
>
> I'm either expecting this function to return -1 here...
>> + }
>> +
>> + if (env->psw.mask & PSW_MASK_PSTATE) {
>> + s390_program_interrupt(env, PGM_PRIVILEGED, ra);
>> + return;
>> + }
>> +
>> + if (reg & ~S390_TOPO_FC_MASK) {
>> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
>> + return;
>> + }
>> +
>> + switch (fc) {
>> + case 0: /* Horizontal polarization is already set */
>> + env->regs[r1] |= S390_PTF_REASON_DONE;
>> + setcc(cpu, 2);
>> + break;
>> + case 1: /* Vertical polarization is not supported */
>> + env->regs[r1] |= S390_PTF_REASON_NONE;
>> + setcc(cpu, 2);
>> + break;
>> + default:
>> + /* Note that fc == 2 is interpreted by the SIE */
>> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
>> + }
>> +}
>
> [...]
>>
>> +static int kvm_handle_ptf(S390CPU *cpu, struct kvm_run *run)
>> +{
>> + uint8_t r1 = (run->s390_sieic.ipb >> 20) & 0x0f;
>> +
>> + s390_handle_ptf(cpu, r1, RA_IGNORED);
>
> ... and this being returned here...
>> +
>> + return 0;
>
> ... or this function being void.
>> +}
Yes right, thanks
Regards,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
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