On Wed, 18 Mar 2020 10:30:40 -0400
Janosch Frank <fran...@linux.ibm.com> wrote:
> SCLP for a protected guest is done over the SIDAD, so we need to use
> the s390_cpu_pv_mem_* functions to access the SIDAD instead of guest
> memory when reading/writing SCBs.
>
> To not confuse the sclp emulation, we set 0x4000 as the SCCB address,
> since the function that injects the sclp external interrupt would
> reject a zero sccb address.
>
> Signed-off-by: Janosch Frank <fran...@linux.ibm.com>
> Reviewed-by: David Hildenbrand <da...@redhat.com>
> Reviewed-by: Claudio Imbrenda <imbre...@linux.ibm.com>
> ---
> hw/s390x/sclp.c | 65 ++++++++++++++++++++++++++++++++++-------
> include/hw/s390x/sclp.h | 2 ++
> target/s390x/kvm.c | 25 ++++++++++++----
> 3 files changed, 76 insertions(+), 16 deletions(-)
>
> diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
> index af0bfbc2eca74767..6486890fecea4b3c 100644
> --- a/hw/s390x/sclp.c
> +++ b/hw/s390x/sclp.c
> @@ -33,6 +33,22 @@ static inline SCLPDevice *get_sclp_device(void)
> return sclp;
> }
>
> +static inline bool sclp_command_code_valid(uint32_t code)
> +{
> + switch (code & SCLP_CMD_CODE_MASK) {
> + case SCLP_CMDW_READ_SCP_INFO:
> + case SCLP_CMDW_READ_SCP_INFO_FORCED:
> + case SCLP_CMDW_READ_CPU_INFO:
> + case SCLP_CMDW_CONFIGURE_IOA:
> + case SCLP_CMDW_DECONFIGURE_IOA:
> + case SCLP_CMD_READ_EVENT_DATA:
> + case SCLP_CMD_WRITE_EVENT_DATA:
> + case SCLP_CMD_WRITE_EVENT_MASK:
> + return true;
> + }
> + return false;
> +}
> +
> static void prepare_cpu_entries(SCLPDevice *sclp, CPUEntry *entry, int
> *count)
> {
> MachineState *ms = MACHINE(qdev_get_machine());
> @@ -193,6 +209,43 @@ static void sclp_execute(SCLPDevice *sclp, SCCB *sccb,
> uint32_t code)
> }
> }
>
> +/*
> + * We only need the address to have something valid for the
> + * service_interrupt call.
> + */
> +#define SCLP_PV_DUMMY_ADDR 0x4000
> +int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb,
> + uint32_t code)
> +{
> + SCLPDevice *sclp = get_sclp_device();
> + SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp);
> + SCCB work_sccb;
> + hwaddr sccb_len = sizeof(SCCB);
> +
> + /*
> + * Only a very limited number of calls is permitted by the
> + * Ultravisor and we support all of them, so we don't check for
This is no longer true, no?
> + * them. All other specification exceptions are also interpreted
> + * by the Ultravisor and hence never cause an exit we need to
> + * handle.
> + *
> + * Setting the CC is also done by the Ultravisor.
> + */
> + s390_cpu_pv_mem_read(env_archcpu(env), 0, &work_sccb, sccb_len);
> +
> + if (!sclp_command_code_valid(code)) {
> + work_sccb.h.response_code =
> cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND);
> + goto out_write;
> + }
> +
> + sclp_c->execute(sclp, &work_sccb, code);
> +out_write:
> + s390_cpu_pv_mem_write(env_archcpu(env), 0, &work_sccb,
> + be16_to_cpu(work_sccb.h.length));
> + sclp_c->service_interrupt(sclp, SCLP_PV_DUMMY_ADDR);
> + return 0;
> +}
> +
> int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code)
> {
> SCLPDevice *sclp = get_sclp_device();
