On Wed, 11 May 2022 10:56:51 +0200
Nico Boehr <nrb@xxxxxxxxxxxxx> wrote:
> Since we're going to need the definitions in an upcoming migration test for CMM,
> add a header for CMM related defines. It is based on
> arch/s390/include/asm/page-states.h from linux.
>
> While at it, use the constants in existing calls to CMM related functions.
>
> Also move essa() and test_availability() there to be able to use it outside
> cmm.c.
>
> Signed-off-by: Nico Boehr <nrb@xxxxxxxxxxxxx>
Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
> ---
> lib/s390x/asm/cmm.h | 50 +++++++++++++++++++++++++++++++++++++++++++++
> s390x/cmm.c | 25 +++--------------------
> 2 files changed, 53 insertions(+), 22 deletions(-)
> create mode 100644 lib/s390x/asm/cmm.h
>
> diff --git a/lib/s390x/asm/cmm.h b/lib/s390x/asm/cmm.h
> new file mode 100644
> index 000000000000..554a60031fbf
> --- /dev/null
> +++ b/lib/s390x/asm/cmm.h
> @@ -0,0 +1,50 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright IBM Corp. 2017, 2022
> + * Author(s): Claudio Imbrenda <imbrenda@xxxxxxxxxxxxxxxxxx>
> + * Nico Boehr <nrb@xxxxxxxxxxxxx>
> + */
> +#include <asm/interrupt.h>
> +
> +#ifndef PAGE_STATES_H
> +#define PAGE_STATES_H
> +
> +#define ESSA_GET_STATE 0
> +#define ESSA_SET_STABLE 1
> +#define ESSA_SET_UNUSED 2
> +#define ESSA_SET_VOLATILE 3
> +#define ESSA_SET_POT_VOLATILE 4
> +#define ESSA_SET_STABLE_RESIDENT 5
> +#define ESSA_SET_STABLE_IF_RESIDENT 6
> +#define ESSA_SET_STABLE_NODAT 7
> +
> +#define ESSA_MAX ESSA_SET_STABLE_NODAT
> +
> +#define ESSA_USAGE_STABLE 0
> +#define ESSA_USAGE_UNUSED 1
> +#define ESSA_USAGE_POT_VOLATILE 2
> +#define ESSA_USAGE_VOLATILE 3
> +
> +static unsigned long essa(uint8_t state, unsigned long paddr)
> +{
> + uint64_t extr_state;
> +
> + asm volatile(".insn rrf,0xb9ab0000,%[extr_state],%[addr],%[new_state],0" \
> + : [extr_state] "=d" (extr_state) \
> + : [addr] "a" (paddr), [new_state] "i" (state));
> +
> + return (unsigned long)extr_state;
> +}
> +
> +/*
> + * Unfortunately the availability is not indicated by stfl bits, but
> + * we have to try to execute it and test for an operation exception.
> + */
> +static inline bool check_essa_available(void)
> +{
> + expect_pgm_int();
> + essa(ESSA_GET_STATE, 0);
> + return clear_pgm_int() == 0;
> +}
> +
> +#endif
> diff --git a/s390x/cmm.c b/s390x/cmm.c
> index c3f0c931ae36..af852838851e 100644
> --- a/s390x/cmm.c
> +++ b/s390x/cmm.c
> @@ -12,19 +12,10 @@
> #include <asm/asm-offsets.h>
> #include <asm/interrupt.h>
> #include <asm/page.h>
> +#include <asm/cmm.h>
>
> static uint8_t pagebuf[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
>
> -static unsigned long essa(uint8_t state, unsigned long paddr)
> -{
> - uint64_t extr_state;
> -
> - asm volatile(".insn rrf,0xb9ab0000,%[extr_state],%[addr],%[new_state],0"
> - : [extr_state] "=d" (extr_state)
> - : [addr] "a" (paddr), [new_state] "i" (state));
> - return (unsigned long)extr_state;
> -}
> -
> static void test_params(void)
> {
> report_prefix_push("invalid ORC 8");
> @@ -39,24 +30,14 @@ static void test_priv(void)
> report_prefix_push("privileged");
> expect_pgm_int();
> enter_pstate();
> - essa(0, (unsigned long)pagebuf);
> + essa(ESSA_GET_STATE, (unsigned long)pagebuf);
> check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
> report_prefix_pop();
> }
>
> -/* Unfortunately the availability is not indicated by stfl bits, but
> - * we have to try to execute it and test for an operation exception.
> - */
> -static bool test_availability(void)
> -{
> - expect_pgm_int();
> - essa(0, (unsigned long)pagebuf);
> - return clear_pgm_int() == 0;
> -}
> -
> int main(void)
> {
> - bool has_essa = test_availability();
> + bool has_essa = check_essa_available();
>
> report_prefix_push("cmm");
> if (!has_essa) {
