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/s390-virtio-ccw.c | 50 ++++++++++++++++++++++++++++++
include/hw/s390x/s390-virtio-ccw.h | 6 ++++
target/s390x/kvm/kvm.c | 14 +++++++++
3 files changed, 70 insertions(+)
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 93d1a43583..1ffaddebcc 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -434,6 +434,56 @@ static void s390_pv_prepare_reset(S390CcwMachineState *ms)
s390_pv_prep_reset();
}
+/*
+ * 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.
+ */
+int 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 0;
+ }
+
+ if (env->psw.mask & PSW_MASK_PSTATE) {
+ s390_program_interrupt(env, PGM_PRIVILEGED, ra);
+ return 0;
+ }
+
+ if (reg & ~S390_TOPO_FC_MASK) {
+ s390_program_interrupt(env, PGM_SPECIFICATION, ra);
+ return 0;
+ }
+
+ switch (fc) {
+ case 0: /* Horizontal polarization is already set */
+ env->regs[r1] |= S390_PTF_REASON_DONE;
+ return 2;
+ case 1: /* Vertical polarization is not supported */
+ env->regs[r1] |= S390_PTF_REASON_NONE;
+ return 2;
+ default:
+ /* Note that fc == 2 is interpreted by the SIE */
+ s390_program_interrupt(env, PGM_SPECIFICATION, ra);
+ }
+
+ return 0;
+}
+
static void s390_machine_reset(MachineState *machine)
{
S390CcwMachineState *ms = S390_CCW_MACHINE(machine);
diff --git a/include/hw/s390x/s390-virtio-ccw.h b/include/hw/s390x/s390-virtio-ccw.h
index 3331990e02..ac4b4a92e7 100644
--- a/include/hw/s390x/s390-virtio-ccw.h
+++ b/include/hw/s390x/s390-virtio-ccw.h
@@ -30,6 +30,12 @@ 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
+int 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 27b3fbfa09..e3792e52c2 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -98,6 +98,7 @@
#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
@@ -1453,6 +1454,16 @@ 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;
+ int ret;
+
+ ret = s390_handle_ptf(cpu, r1, RA_IGNORED);
+ setcc(cpu, ret);
+ return 0;
+}
+
static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
{
int r = 0;
@@ -1470,6 +1481,9 @@ 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;
--
2.27.0On 20/04/2022 13.57, 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>
> ---
> hw/s390x/s390-virtio-ccw.c | 50 ++++++++++++++++++++++++++++++
> include/hw/s390x/s390-virtio-ccw.h | 6 ++++
> target/s390x/kvm/kvm.c | 14 +++++++++
> 3 files changed, 70 insertions(+)
>
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index 93d1a43583..1ffaddebcc 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
Why do you put this into s390-virtio-ccw.c and not into cpu_topology.c ?
> @@ -434,6 +434,56 @@ static void s390_pv_prepare_reset(S390CcwMachineState *ms)
> s390_pv_prep_reset();
> }
>
> +/*
> + * 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.
> + */
> +int 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 0;
> + }
> +
> + if (env->psw.mask & PSW_MASK_PSTATE) {
> + s390_program_interrupt(env, PGM_PRIVILEGED, ra);
> + return 0;
> + }
> +
> + if (reg & ~S390_TOPO_FC_MASK) {
> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
> + return 0;
> + }
> +
> + switch (fc) {
> + case 0: /* Horizontal polarization is already set */
> + env->regs[r1] |= S390_PTF_REASON_DONE;
> + return 2;
> + case 1: /* Vertical polarization is not supported */
> + env->regs[r1] |= S390_PTF_REASON_NONE;
> + return 2;
> + default:
> + /* Note that fc == 2 is interpreted by the SIE */
> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
> + }
> +
> + return 0;
> +}
> +
> static void s390_machine_reset(MachineState *machine)
> {
> S390CcwMachineState *ms = S390_CCW_MACHINE(machine);
> diff --git a/include/hw/s390x/s390-virtio-ccw.h b/include/hw/s390x/s390-virtio-ccw.h
> index 3331990e02..ac4b4a92e7 100644
> --- a/include/hw/s390x/s390-virtio-ccw.h
> +++ b/include/hw/s390x/s390-virtio-ccw.h
> @@ -30,6 +30,12 @@ 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
> +int 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 27b3fbfa09..e3792e52c2 100644
> --- a/target/s390x/kvm/kvm.c
> +++ b/target/s390x/kvm/kvm.c
> @@ -98,6 +98,7 @@
>
> #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
> @@ -1453,6 +1454,16 @@ 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;
> + int ret;
> +
> + ret = s390_handle_ptf(cpu, r1, RA_IGNORED);
> + setcc(cpu, ret);
So you're still setting the CC in case the s390_handle_ptf() function
injected a program interrupt? ... feels wrong. Maybe the CC should be set
within s390_handle_ptf() instead?
Thomas
> + return 0;
> +}
> +
> static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
> {
> int r = 0;
> @@ -1470,6 +1481,9 @@ 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 5/24/22 13:27, Thomas Huth wrote:
> On 20/04/2022 13.57, 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>
>> ---
>> hw/s390x/s390-virtio-ccw.c | 50 ++++++++++++++++++++++++++++++
>> include/hw/s390x/s390-virtio-ccw.h | 6 ++++
>> target/s390x/kvm/kvm.c | 14 +++++++++
>> 3 files changed, 70 insertions(+)
>>
>> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
>> index 93d1a43583..1ffaddebcc 100644
>> --- a/hw/s390x/s390-virtio-ccw.c
>> +++ b/hw/s390x/s390-virtio-ccw.c
>
> Why do you put this into s390-virtio-ccw.c and not into cpu_topology.c ?
Should have historical reason I forgot in between.
I will move it in cpu_topology.c
>
>> @@ -434,6 +434,56 @@ static void
>> s390_pv_prepare_reset(S390CcwMachineState *ms)
>> s390_pv_prep_reset();
>> }
>> +/*
>> + * 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.
>> + */
>> +int s390_has390_handle_ptfndle_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 0;
>> + }
>> +
>> + if (env->psw.mask & PSW_MASK_PSTATE) {
>> + s390_program_interrupt(env, PGM_PRIVILEGED, ra);
>> + return 0;
>> + }
>> +
>> + if (reg & ~S390_TOPO_FC_MASK) {
>> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
>> + return 0;
>> + }
>> +
>> + switch (fc) {
>> + case 0: /* Horizontal polarization is already set */
>> + env->regs[r1] |= S390_PTF_REASON_DONE;
>> + return 2;
>> + case 1: /* Vertical polarization is not supported */
>> + env->regs[r1] |= S390_PTF_REASON_NONE;
>> + return 2;
>> + default:
>> + /* Note that fc == 2 is interpreted by the SIE */
>> + s390_program_interrupt(env, PGM_SPECIFICATION, ra);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> static void s390_machine_reset(MachineState *machine)
>> {
>> S390CcwMachineState *ms = S390_CCW_MACHINE(machine);
>> diff --git a/include/hw/s390x/s390-virtio-ccw.h
>> b/include/hw/s390x/s390-virtio-ccw.h
>> index 3331990e02..ac4b4a92e7 100644
>> --- a/include/hw/s390x/s390-virtio-ccw.h
>> +++ b/include/hw/s390x/s390-virtio-ccw.h
>> @@ -30,6 +30,12 @@ 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
>> +int 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 27b3fbfa09..e3792e52c2 100644
>> --- a/target/s390x/kvm/kvm.c
>> +++ b/target/s390x/kvm/kvm.c
>> @@ -98,6 +98,7 @@
>> #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
>> @@ -1453,6 +1454,16 @@ 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;
>> + int ret;
>> +
>> + ret = s390_handle_ptf(cpu, r1, RA_IGNORED);
>> + setcc(cpu, ret);
>
> So you're still setting the CC in case the s390_handle_ptf() function
> injected a program interrupt? ... feels wrong. Maybe the CC should be
> set within s390_handle_ptf() instead?
OK, I will have a look and change it.
Thanks,
Pierre
>
> Thomas
>
>
>> + return 0;
>> +}
>> +
>> static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
>> {
>> int r = 0;
>> @@ -1470,6 +1481,9 @@ 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;
>
--
Pierre Morel
IBM Lab Boeblingen
© 2016 - 2026 Red Hat, Inc.