From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:65496 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730066AbgK0NJK (ORCPT ); Fri, 27 Nov 2020 08:09:10 -0500 From: Janosch Frank Subject: [kvm-unit-tests PATCH v2 1/7] s390x: Add test_bit to library Date: Fri, 27 Nov 2020 08:06:23 -0500 Message-Id: <20201127130629.120469-2-frankja@linux.ibm.com> In-Reply-To: <20201127130629.120469-1-frankja@linux.ibm.com> References: <20201127130629.120469-1-frankja@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit List-ID: To: kvm@vger.kernel.org Cc: thuth@redhat.com, david@redhat.com, borntraeger@de.ibm.com, imbrenda@linux.ibm.com, cohuck@redhat.com, linux-s390@vger.kernel.org Query/feature bits are commonly tested via MSB bit numbers on s390. Let's add test bit functions, so we don't need to copy code to test query bits. The test_bit code has been taken from the kernel since most s390x KVM unit test developers are used to them. Signed-off-by: Janosch Frank Reviewed-by: Cornelia Huck Reviewed-by: Thomas Huth --- lib/s390x/asm/bitops.h | 26 ++++++++++++++++++++++++++ lib/s390x/asm/facility.h | 3 ++- 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/lib/s390x/asm/bitops.h b/lib/s390x/asm/bitops.h index e7cdda9..792881e 100644 --- a/lib/s390x/asm/bitops.h +++ b/lib/s390x/asm/bitops.h @@ -1,3 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Bitops taken from the kernel as most developers are already used + * to them. + * + * Copyright IBM Corp. 1999,2013 + * + * Author(s): Martin Schwidefsky , + * + */ #ifndef _ASMS390X_BITOPS_H_ #define _ASMS390X_BITOPS_H_ @@ -7,4 +17,20 @@ #define BITS_PER_LONG 64 +static inline bool test_bit(unsigned long nr, + const volatile unsigned long *ptr) +{ + const volatile unsigned char *addr; + + addr = ((const volatile unsigned char *)ptr); + addr += (nr ^ (BITS_PER_LONG - 8)) >> 3; + return (*addr >> (nr & 7)) & 1; +} + +static inline bool test_bit_inv(unsigned long nr, + const volatile unsigned long *ptr) +{ + return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); +} + #endif diff --git a/lib/s390x/asm/facility.h b/lib/s390x/asm/facility.h index def2705..5593c2d 100644 --- a/lib/s390x/asm/facility.h +++ b/lib/s390x/asm/facility.h @@ -13,13 +13,14 @@ #include #include #include +#include #define NB_STFL_DOUBLEWORDS 32 extern uint64_t stfl_doublewords[]; static inline bool test_facility(int nr) { - return stfl_doublewords[nr / 64] & (0x8000000000000000UL >> (nr % 64)); + return test_bit_inv(nr, stfl_doublewords); } static inline void stfl(void) -- 2.25.1