Re: [kvm-unit-tests PATCH 3/6] s390x: uv: Add UV lib

[Janosch Frank <frankja@linux.ibm.com>]

On 4/20/21 4:15 PM, Claudio Imbrenda wrote:
> On Tue, 16 Mar 2021 09:16:51 +0000
> Janosch Frank <frankja@linux.ibm.com> wrote:
> 
>> Let's add a UV library to make checking the UV feature bit easier.
>> In the future this library file can take care of handling UV
>> initialization and UV guest creation.
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> 
> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

Thanks

> 
> but see some comments below
> 
>> ---
>>  lib/s390x/asm/uv.h |  4 ++--
>>  lib/s390x/io.c     |  2 ++
>>  lib/s390x/uv.c     | 48
>> ++++++++++++++++++++++++++++++++++++++++++++++ lib/s390x/uv.h     |
>> 10 ++++++++++ s390x/Makefile     |  1 +
>>  5 files changed, 63 insertions(+), 2 deletions(-)
>>  create mode 100644 lib/s390x/uv.c
>>  create mode 100644 lib/s390x/uv.h
>>
>> diff --git a/lib/s390x/asm/uv.h b/lib/s390x/asm/uv.h
>> index 11f70a9f..b22cbaa8 100644
>> --- a/lib/s390x/asm/uv.h
>> +++ b/lib/s390x/asm/uv.h
>> @@ -9,8 +9,8 @@
>>   * This code is free software; you can redistribute it and/or modify
>> it
>>   * under the terms of the GNU General Public License version 2.
>>   */
>> -#ifndef UV_H
>> -#define UV_H
>> +#ifndef ASM_S390X_UV_H
>> +#define ASM_S390X_UV_H
>>  
>>  #define UVC_RC_EXECUTED		0x0001
>>  #define UVC_RC_INV_CMD		0x0002
>> diff --git a/lib/s390x/io.c b/lib/s390x/io.c
>> index ef9f59e3..a4f1b113 100644
>> --- a/lib/s390x/io.c
>> +++ b/lib/s390x/io.c
>> @@ -14,6 +14,7 @@
>>  #include <asm/facility.h>
>>  #include <asm/sigp.h>
>>  #include "sclp.h"
>> +#include "uv.h"
>>  #include "smp.h"
>>  
>>  extern char ipl_args[];
>> @@ -38,6 +39,7 @@ void setup(void)
>>  	sclp_facilities_setup();
>>  	sclp_console_setup();
>>  	sclp_memory_setup();
>> +	uv_setup();
>>  	smp_setup();
>>  }
>>  
>> diff --git a/lib/s390x/uv.c b/lib/s390x/uv.c
>> new file mode 100644
>> index 00000000..a84a85fc
>> --- /dev/null
>> +++ b/lib/s390x/uv.c
>> @@ -0,0 +1,48 @@
>> +#include <libcflat.h>
>> +#include <bitops.h>
>> +#include <alloc.h>
>> +#include <alloc_page.h>
>> +#include <asm/page.h>
>> +#include <asm/arch_def.h>
>> +
>> +#include <asm/facility.h>
>> +#include <asm/uv.h>
>> +#include <uv.h>
>> +
>> +static struct uv_cb_qui uvcb_qui = {
>> +	.header.cmd = UVC_CMD_QUI,
>> +	.header.len = sizeof(uvcb_qui),
>> +};
>> +
>> +bool uv_os_is_guest(void)
>> +{
>> +	return uv_query_test_feature(BIT_UVC_CMD_SET_SHARED_ACCESS)
>> +		&&
>> uv_query_test_feature(BIT_UVC_CMD_REMOVE_SHARED_ACCESS); +}
>> +
>> +bool uv_os_is_host(void)
>> +{
>> +	return uv_query_test_feature(BIT_UVC_CMD_INIT_UV);
>> +}
>> +
>> +bool uv_query_test_feature(int nr)
>> +{
>> +	/* Query needs to be called first */
>> +	if (!uvcb_qui.header.rc)
>> +		return false;
> 
> why not an assert?

I'd guess I had some weird reservation.
I'll add one though

> 
>> +
>> +	return test_bit_inv(nr, uvcb_qui.inst_calls_list);
>> +}
>> +
>> +int uv_setup(void)
>> +{
>> +	int cc;
>> +
>> +	if (!test_facility(158))
>> +		return 0;
>> +
>> +	cc = uv_call(0, (u64)&uvcb_qui);
>> +	assert(cc == 0);
>> +
>> +	return cc == 0;
> 
> sooo... return 1?

Yes

> 
>> +}
>> diff --git a/lib/s390x/uv.h b/lib/s390x/uv.h
>> new file mode 100644
>> index 00000000..159bf8e5
>> --- /dev/null
>> +++ b/lib/s390x/uv.h
>> @@ -0,0 +1,10 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +#ifndef UV_H
>> +#define UV_H
>> +
>> +bool uv_os_is_guest(void);
>> +bool uv_os_is_host(void);
>> +bool uv_query_test_feature(int nr);
>> +int uv_setup(void);
>> +
>> +#endif /* UV_H */
>> diff --git a/s390x/Makefile b/s390x/Makefile
>> index b92de9c5..bbf177fa 100644
>> --- a/s390x/Makefile
>> +++ b/s390x/Makefile
>> @@ -67,6 +67,7 @@ cflatobjs += lib/s390x/vm.o
>>  cflatobjs += lib/s390x/css_dump.o
>>  cflatobjs += lib/s390x/css_lib.o
>>  cflatobjs += lib/s390x/malloc_io.o
>> +cflatobjs += lib/s390x/uv.o
>>  
>>  OBJDIRS += lib/s390x
>>  
>