On Mon, 15 Jun 2020 11:31:53 +0200
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
Subject: "s390: I/O interrupt registration" ?
> Let's make it possible to add and remove a custom io interrupt handler,
> that can be used instead of the normal one.
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx>
> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
> Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
> ---
> lib/s390x/interrupt.c | 23 ++++++++++++++++++++++-
> lib/s390x/interrupt.h | 8 ++++++++
> 2 files changed, 30 insertions(+), 1 deletion(-)
> create mode 100644 lib/s390x/interrupt.h
>
> diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c
> index 3a40cac..243b9c2 100644
> --- a/lib/s390x/interrupt.c
> +++ b/lib/s390x/interrupt.c
> @@ -10,9 +10,9 @@
> * under the terms of the GNU Library General Public License version 2.
> */
> #include <libcflat.h>
> -#include <asm/interrupt.h>
> #include <asm/barrier.h>
> #include <sclp.h>
> +#include <interrupt.h>
>
> static bool pgm_int_expected;
> static bool ext_int_expected;
> @@ -144,12 +144,33 @@ void handle_mcck_int(void)
> stap(), lc->mcck_old_psw.addr);
> }
>
> +static void (*io_int_func)(void);
> +
> void handle_io_int(void)
> {
> + if (io_int_func)
> + return io_int_func();
> +
> report_abort("Unexpected io interrupt: on cpu %d at %#lx",
> stap(), lc->io_old_psw.addr);
> }
>
> +int register_io_int_func(void (*f)(void))
> +{
> + if (io_int_func)
> + return -1;
> + io_int_func = f;
> + return 0;
> +}
> +
> +int unregister_io_int_func(void (*f)(void))
> +{
> + if (io_int_func != f)
> + return -1;
Not sure if we really need these checks, but they don't hurt, either.
> + io_int_func = NULL;
> + return 0;
> +}
> +
> void handle_svc_int(void)
> {
> report_abort("Unexpected supervisor call interrupt: on cpu %d at %#lx",
Acked-by: Cornelia Huck <cohuck@xxxxxxxxxx>
