On 20.03.2018 12:19, Janosch Frank wrote:
> Storage keys are not used by Linux anymore, so let's show them some
> love and test if the basics still work.
>
> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>
> ---
> lib/s390x/asm/mem.h | 52 +++++++++++++++++++++++++++++
> s390x/Makefile | 1 +
> s390x/skey.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> s390x/unittests.cfg | 3 ++
> 4 files changed, 150 insertions(+)
> create mode 100644 lib/s390x/asm/mem.h
> create mode 100644 s390x/skey.c
>
> diff --git a/lib/s390x/asm/mem.h b/lib/s390x/asm/mem.h
> new file mode 100644
> index 0000000..909e6d4
> --- /dev/null
> +++ b/lib/s390x/asm/mem.h
> @@ -0,0 +1,52 @@
> +/*
> + * Physical memory management related functions and definitions.
> + *
> + * Copyright IBM Corp. 2018
> + * Author(s): Janosch Frank <frankja@xxxxxxxxxx>
> + *
> + * This code is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU Library General Public License version 2.
> + */
> +#ifndef _ASM_S390_MEM_H
> +#define _ASM_S390_MEM_H
> +
> +union skey {
> + struct {
> + uint8_t acc : 4;
> + uint8_t fp : 1;
> + uint8_t rf : 1;
> + uint8_t ch : 1;
> + uint8_t pad : 1;
> + } str;
> + uint8_t val;
> +};
> +
> +static inline void set_storage_key(unsigned long addr,
> + unsigned char skey,
> + int nq)
> +{
> + if (nq)
> + asm volatile(".insn rrf,0xb22b0000,%0,%1,8,0"
> + : : "d" (skey), "a" (addr));
> + else
> + asm volatile("sske %0,%1" : : "d" (skey), "a" (addr));
> +}
> +
> +static inline unsigned long set_storage_key_mb(unsigned long addr,
> + unsigned char skey)
> +{
> + assert(test_facility(8));
> +
> + asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],1,0"
> + : [addr] "+a" (addr) : [skey] "d" (skey));
> + return addr;
> +}
> +
> +static inline unsigned char get_storage_key(unsigned long addr)
> +{
> + unsigned char skey;
> +
> + asm volatile("iske %0,%1" : "=d" (skey) : "a" (addr));
> + return skey;
> +}
> +#endif
> diff --git a/s390x/Makefile b/s390x/Makefile
> index e062727..b73031d 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -3,6 +3,7 @@ tests += $(TEST_DIR)/intercept.elf
> tests += $(TEST_DIR)/emulator.elf
> tests += $(TEST_DIR)/sieve.elf
> tests += $(TEST_DIR)/sthyi.elf
> +tests += $(TEST_DIR)/skey.elf
>
> all: directories test_cases
>
> diff --git a/s390x/skey.c b/s390x/skey.c
> new file mode 100644
> index 0000000..e4c2a43
> --- /dev/null
> +++ b/s390x/skey.c
> @@ -0,0 +1,94 @@
> +/*
> + * Storage key tests
> + *
> + * Copyright (c) 2018 IBM Corp
> + *
> + * Authors:
> + * Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>
> + *
> + * This code is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU Library General Public License version 2.
> + */
> +#include <libcflat.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/interrupt.h>
> +#include <asm/page.h>
> +#include <asm/facility.h>
> +#include <asm/mem.h>
> +
> +
> +static uint8_t pagebuf[PAGE_SIZE * 2] __attribute__((aligned(PAGE_SIZE * 2)));
> +const unsigned long page0 = (unsigned long)pagebuf;
> +const unsigned long page1 = (unsigned long)(pagebuf + PAGE_SIZE);
> +
> +static void test_set_mb(void)
> +{
> + union skey skey, ret1, ret2;
> + unsigned long addr = 0x10000 - 2 * PAGE_SIZE;
> + unsigned long end = 0x10000;
> +
> + /* Multi block support came with EDAT 1 */
> + if (!test_facility(8))
> + return;
> +
> + skey.val = 0x30;
> + while (addr < end)
> + addr = set_storage_key_mb(addr, skey.val);
> +
> + ret1.val = get_storage_key(end - PAGE_SIZE);
> + ret2.val = get_storage_key(end - PAGE_SIZE * 2);
> + report("multi block", ret1.val == ret2.val && ret1.val == skey.val);
> +}
> +
> +static void test_chg(void)
> +{
> + union skey skey1, skey2;
> +
> + skey1.val = 0x30;
> + set_storage_key(page0, skey1.val, 0);
> + skey1.val = get_storage_key(page0);
> + pagebuf[0] = 3;
> + skey2.val = get_storage_key(page0);
> + report("chg bit test", !skey1.str.ch && skey2.str.ch);
> +}
> +
> +static void test_set(void)
> +{
> + union skey skey, ret;
> +
> + skey.val = 0x30;
> + ret.val = get_storage_key(page0);
> + set_storage_key(page0, skey.val, 0);
> + ret.val = get_storage_key(page0);
> + report("set key test", skey.val == ret.val);
> +}
> +
> +static void test_priv(void)
> +{
> + union skey skey;
> +
> + memset(pagebuf, 0, PAGE_SIZE * 2);
> + expect_pgm_int();
> + enter_pstate();
> + set_storage_key(page0, 0x30, 0);
> + check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
> +
> + skey.val = get_storage_key(page0);
> + report("skey did not change on exception", skey.str.acc != 3);
> +
> + expect_pgm_int();
> + enter_pstate();
> + get_storage_key(page0);
> + check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
> +}
> +
> +int main(void)
> +{
> + report_prefix_push("skey");
> + test_priv();
> + test_set();
> + test_set_mb();
> + test_chg();
> + report_prefix_pop();
> + return report_summary();
> +}
> diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
> index 506891a..8321e9b 100644
> --- a/s390x/unittests.cfg
> +++ b/s390x/unittests.cfg
> @@ -38,3 +38,6 @@ timeout = 600
> [sthyi]
> file = sthyi.elf
> accel = kvm
> +
> +[skey]
> +file = skey.elf
>
Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx>
