Re: [kvm-unit-tests PATCH 1/5] lib: s390x: vm: Add kvm and lpar vm queries

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Fri, 14 Jan 2022 10:02:41 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> This patch will likely (in parts) be replaced by Pierre's patch from
> his topology test series.
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

although I think there is some room for improvement, but nothing too
serious, I'll probably fix it myself later

> ---
>  lib/s390x/vm.c | 39 +++++++++++++++++++++++++++++++++++++++
>  lib/s390x/vm.h | 23 +++++++++++++++++++++++
>  s390x/stsi.c   | 21 +--------------------
>  3 files changed, 63 insertions(+), 20 deletions(-)
> 
> diff --git a/lib/s390x/vm.c b/lib/s390x/vm.c
> index a5b92863..266a81c1 100644
> --- a/lib/s390x/vm.c
> +++ b/lib/s390x/vm.c
> @@ -26,6 +26,11 @@ bool vm_is_tcg(void)
>  	if (initialized)
>  		return is_tcg;
>  
> +	if (stsi_get_fc() < 3) {
> +		initialized = true;
> +		return false;
> +	}
> +
>  	buf = alloc_page();
>  	if (!buf)
>  		return false;
> @@ -43,3 +48,37 @@ out:
>  	free_page(buf);
>  	return is_tcg;
>  }
> +
> +bool vm_is_kvm(void)
> +{
> +	const uint8_t cpi_kvm[] = { 0xd2, 0xe5, 0xd4, 0x61 };
> +	struct stsi_322 *buf;
> +	static bool initialized = false;
> +	static bool is_kvm = false;
> +
> +	if (initialized)
> +		return is_kvm;
> +
> +	if (stsi_get_fc() < 3) {
> +		initialized = true;
> +		return false;
> +	}
> +
> +	buf = alloc_page();
> +	if (!buf)
> +		return false;
> +
> +	if (stsi(buf, 3, 2, 2))
> +		goto out;
> +
> +	is_kvm = !(memcmp(&buf->vm[0].cpi, cpi_kvm, sizeof(cpi_kvm))) && !vm_is_tcg();
> +	initialized = true;
> +out:
> +	free_page(buf);
> +	return is_kvm;
> +}
> +
> +bool vm_is_lpar(void)
> +{
> +	return stsi_get_fc() == 1;
> +}
> diff --git a/lib/s390x/vm.h b/lib/s390x/vm.h
> index 7abba0cc..d4a82fc0 100644
> --- a/lib/s390x/vm.h
> +++ b/lib/s390x/vm.h
> @@ -8,6 +8,29 @@
>  #ifndef _S390X_VM_H_
>  #define _S390X_VM_H_
>  
> +struct stsi_322 {
> +	uint8_t reserved[31];
> +	uint8_t count;
> +	struct {
> +		uint8_t reserved2[4];
> +		uint16_t total_cpus;
> +		uint16_t conf_cpus;
> +		uint16_t standby_cpus;
> +		uint16_t reserved_cpus;
> +		uint8_t name[8];
> +		uint32_t caf;
> +		uint8_t cpi[16];
> +		uint8_t reserved5[3];
> +		uint8_t ext_name_encoding;
> +		uint32_t reserved3;
> +		uint8_t uuid[16];
> +	} vm[8];
> +	uint8_t reserved4[1504];
> +	uint8_t ext_names[8][256];
> +};
> +
>  bool vm_is_tcg(void);
> +bool vm_is_kvm(void);
> +bool vm_is_lpar(void);
>  
>  #endif  /* _S390X_VM_H_ */
> diff --git a/s390x/stsi.c b/s390x/stsi.c
> index 391f8849..e66d07a1 100644
> --- a/s390x/stsi.c
> +++ b/s390x/stsi.c
> @@ -13,27 +13,8 @@
>  #include <asm/asm-offsets.h>
>  #include <asm/interrupt.h>
>  #include <smp.h>
> +#include <vm.h>
>  
> -struct stsi_322 {
> -	uint8_t reserved[31];
> -	uint8_t count;
> -	struct {
> -		uint8_t reserved2[4];
> -		uint16_t total_cpus;
> -		uint16_t conf_cpus;
> -		uint16_t standby_cpus;
> -		uint16_t reserved_cpus;
> -		uint8_t name[8];
> -		uint32_t caf;
> -		uint8_t cpi[16];
> -		uint8_t reserved5[3];
> -		uint8_t ext_name_encoding;
> -		uint32_t reserved3;
> -		uint8_t uuid[16];
> -	} vm[8];
> -	uint8_t reserved4[1504];
> -	uint8_t ext_names[8][256];
> -};
>  static uint8_t pagebuf[PAGE_SIZE * 2] __attribute__((aligned(PAGE_SIZE * 2)));
>  
>  static void test_specs(void)