diff mbox series

[kvm-unit-tests,v6,1/8] lib: s390x: introduce bitfield for PSW mask

Message ID 20230904082318.1465055-2-nrb@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x: Add support for running guests without MSO/MSL | expand

Commit Message

Nico Boehr Sept. 4, 2023, 8:22 a.m. UTC
Changing the PSW mask is currently little clumsy, since there is only the
PSW_MASK_* defines. This makes it hard to change e.g. only the address
space in the current PSW without a lot of bit fiddling.

Introduce a bitfield for the PSW mask. This makes this kind of
modifications much simpler and easier to read.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
---
 lib/s390x/asm/arch_def.h | 26 +++++++++++++++++++++++++-
 s390x/selftest.c         | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 1 deletion(-)

Comments

Thomas Huth Sept. 4, 2023, 9:49 a.m. UTC | #1
On 04/09/2023 10.22, Nico Boehr wrote:
> Changing the PSW mask is currently little clumsy, since there is only the
> PSW_MASK_* defines. This makes it hard to change e.g. only the address
> space in the current PSW without a lot of bit fiddling.
> 
> Introduce a bitfield for the PSW mask. This makes this kind of
> modifications much simpler and easier to read.
> 
> Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
> ---
>   lib/s390x/asm/arch_def.h | 26 +++++++++++++++++++++++++-
>   s390x/selftest.c         | 34 ++++++++++++++++++++++++++++++++++
>   2 files changed, 59 insertions(+), 1 deletion(-)

Reviewed-by: Thomas Huth <thuth@redhat.com>
Janosch Frank Sept. 5, 2023, 12:22 p.m. UTC | #2
On 9/4/23 10:22, Nico Boehr wrote:
> Changing the PSW mask is currently little clumsy, since there is only the
> PSW_MASK_* defines. This makes it hard to change e.g. only the address
> space in the current PSW without a lot of bit fiddling.
> 
> Introduce a bitfield for the PSW mask. This makes this kind of
> modifications much simpler and easier to read.
> 
> Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
> ---
>   lib/s390x/asm/arch_def.h | 26 +++++++++++++++++++++++++-
>   s390x/selftest.c         | 34 ++++++++++++++++++++++++++++++++++
>   2 files changed, 59 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
> index bb26e008cc68..5a712f97f129 100644
> --- a/lib/s390x/asm/arch_def.h
> +++ b/lib/s390x/asm/arch_def.h
> @@ -37,12 +37,36 @@ struct stack_frame_int {
>   };
>   
>   struct psw {
> -	uint64_t	mask;
> +	union {
> +		uint64_t	mask;
> +		struct {
> +			uint64_t reserved00:1;
> +			uint64_t per:1;
> +			uint64_t reserved02:3;
> +			uint64_t dat:1;
> +			uint64_t io:1;
> +			uint64_t ext:1;
> +			uint64_t key:4;
> +			uint64_t reserved12:1;
> +			uint64_t mchk:1;
> +			uint64_t wait:1;
> +			uint64_t pstate:1;
> +			uint64_t as:2;
> +			uint64_t cc:2;
> +			uint64_t prg_mask:4;
> +			uint64_t reserved24:7;
> +			uint64_t ea:1;
> +			uint64_t ba:1;
> +			uint64_t reserved33:31;
> +		};
> +	};
>   	uint64_t	addr;
>   };
> +_Static_assert(sizeof(struct psw) == 16, "PSW size");
>   
>   #define PSW(m, a) ((struct psw){ .mask = (m), .addr = (uint64_t)(a) })
>   
> +

We can fix this up when picking.

Other than that:
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
diff mbox series

Patch

diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
index bb26e008cc68..5a712f97f129 100644
--- a/lib/s390x/asm/arch_def.h
+++ b/lib/s390x/asm/arch_def.h
@@ -37,12 +37,36 @@  struct stack_frame_int {
 };
 
 struct psw {
-	uint64_t	mask;
+	union {
+		uint64_t	mask;
+		struct {
+			uint64_t reserved00:1;
+			uint64_t per:1;
+			uint64_t reserved02:3;
+			uint64_t dat:1;
+			uint64_t io:1;
+			uint64_t ext:1;
+			uint64_t key:4;
+			uint64_t reserved12:1;
+			uint64_t mchk:1;
+			uint64_t wait:1;
+			uint64_t pstate:1;
+			uint64_t as:2;
+			uint64_t cc:2;
+			uint64_t prg_mask:4;
+			uint64_t reserved24:7;
+			uint64_t ea:1;
+			uint64_t ba:1;
+			uint64_t reserved33:31;
+		};
+	};
 	uint64_t	addr;
 };
+_Static_assert(sizeof(struct psw) == 16, "PSW size");
 
 #define PSW(m, a) ((struct psw){ .mask = (m), .addr = (uint64_t)(a) })
 
+
 struct short_psw {
 	uint32_t	mask;
 	uint32_t	addr;
diff --git a/s390x/selftest.c b/s390x/selftest.c
index 13fd36bc06f8..92ed4e5d35eb 100644
--- a/s390x/selftest.c
+++ b/s390x/selftest.c
@@ -74,6 +74,39 @@  static void test_malloc(void)
 	report_prefix_pop();
 }
 
+static void test_psw_mask(void)
+{
+	uint64_t expected_key = 0xf;
+	struct psw test_psw = PSW(0, 0);
+
+	report_prefix_push("PSW mask");
+	test_psw.mask = PSW_MASK_DAT;
+	report(test_psw.dat, "DAT matches expected=0x%016lx actual=0x%016lx", PSW_MASK_DAT, test_psw.mask);
+
+	test_psw.mask = PSW_MASK_IO;
+	report(test_psw.io, "IO matches expected=0x%016lx actual=0x%016lx", PSW_MASK_IO, test_psw.mask);
+
+	test_psw.mask = PSW_MASK_EXT;
+	report(test_psw.ext, "EXT matches expected=0x%016lx actual=0x%016lx", PSW_MASK_EXT, test_psw.mask);
+
+	test_psw.mask = expected_key << (63 - 11);
+	report(test_psw.key == expected_key, "PSW Key matches expected=0x%lx actual=0x%x", expected_key, test_psw.key);
+
+	test_psw.mask = 1UL << (63 - 13);
+	report(test_psw.mchk, "MCHK matches");
+
+	test_psw.mask = PSW_MASK_WAIT;
+	report(test_psw.wait, "Wait matches expected=0x%016lx actual=0x%016lx", PSW_MASK_WAIT, test_psw.mask);
+
+	test_psw.mask = PSW_MASK_PSTATE;
+	report(test_psw.pstate, "Pstate matches expected=0x%016lx actual=0x%016lx", PSW_MASK_PSTATE, test_psw.mask);
+
+	test_psw.mask = PSW_MASK_64;
+	report(test_psw.ea && test_psw.ba, "BA/EA matches expected=0x%016lx actual=0x%016lx", PSW_MASK_64, test_psw.mask);
+
+	report_prefix_pop();
+}
+
 int main(int argc, char**argv)
 {
 	report_prefix_push("selftest");
@@ -89,6 +122,7 @@  int main(int argc, char**argv)
 	test_fp();
 	test_pgm_int();
 	test_malloc();
+	test_psw_mask();
 
 	return report_summary();
 }