From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44F6FC282C2 for ; Wed, 23 Jan 2019 11:10:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EE6A21019 for ; Wed, 23 Jan 2019 11:10:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727276AbfAWLKJ (ORCPT ); Wed, 23 Jan 2019 06:10:09 -0500 Received: from mail.cn.fujitsu.com ([183.91.158.132]:7521 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727181AbfAWLKH (ORCPT ); Wed, 23 Jan 2019 06:10:07 -0500 X-IronPort-AV: E=Sophos;i="5.56,510,1539619200"; d="scan'208";a="52651109" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 23 Jan 2019 19:10:03 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id 31EDF4C4A88D; Wed, 23 Jan 2019 19:10:03 +0800 (CST) Received: from localhost.local (10.167.225.56) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Wed, 23 Jan 2019 19:10:09 +0800 From: Chao Fan To: , , , , , , , , CC: , , , Subject: [PATCH v16 1/7] x86/boot: Copy kstrtoull() to boot/string.c instead of simple_strtoull() Date: Wed, 23 Jan 2019 19:08:44 +0800 Message-ID: <20190123110850.12433-2-fanc.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190123110850.12433-1-fanc.fnst@cn.fujitsu.com> References: <20190123110850.12433-1-fanc.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.167.225.56] X-yoursite-MailScanner-ID: 31EDF4C4A88D.AAC8E X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: fanc.fnst@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Copy kstrtoull() and necessary functions from lib/kstrtox.c to boot/string.c so that code in boot/ can use kstrtoull() and the old simple_strtoull() can be replaced. In boot/string.c, using div_u64() from math64.h directly will cause the dividend handled as 64-bit value and bring ld error. The solution is to separate the dividend to upper and lower in boot/string.o. So copy the useful div_u64() and div_u64_rem() to boot/string.c also. To avoid redefinition in i386, rename them as __div_u64() and __div_u64_rem(). Signed-off-by: Chao Fan --- arch/x86/boot/string.c | 141 +++++++++++++++++++++++++++++++++++++++++ arch/x86/boot/string.h | 1 + 2 files changed, 142 insertions(+) diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c index c4428a176973..315a67b8896b 100644 --- a/arch/x86/boot/string.c +++ b/arch/x86/boot/string.c @@ -13,10 +13,14 @@ */ #include +#include +#include #include #include "ctype.h" #include "string.h" +#define KSTRTOX_OVERFLOW (1U << 31) + /* * Undef these macros so that the functions that we provide * here will have the correct names regardless of how string.h @@ -187,3 +191,140 @@ char *strchr(const char *s, int c) return NULL; return (char *)s; } + +static inline u64 __div_u64_rem(u64 dividend, u32 divisor, u32 *remainder) +{ + union { + u64 v64; + u32 v32[2]; + } d = { dividend }; + u32 upper; + + upper = d.v32[1]; + d.v32[1] = 0; + if (upper >= divisor) { + d.v32[1] = upper / divisor; + upper %= divisor; + } + asm ("divl %2" : "=a" (d.v32[0]), "=d" (*remainder) : + "rm" (divisor), "0" (d.v32[0]), "1" (upper)); + return d.v64; +} + +static inline u64 __div_u64(u64 dividend, u32 divisor) +{ + u32 remainder; + + return __div_u64_rem(dividend, divisor, &remainder); +} + +static inline char _tolower(const char c) +{ + return c | 0x20; +} + +static const char *_parse_integer_fixup_radix(const char *s, unsigned int *base) +{ + if (*base == 0) { + if (s[0] == '0') { + if (_tolower(s[1]) == 'x' && isxdigit(s[2])) + *base = 16; + else + *base = 8; + } else + *base = 10; + } + if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x') + s += 2; + return s; +} + +/* + * Convert non-negative integer string representation in explicitly given radix + * to an integer. + * Return number of characters consumed maybe or-ed with overflow bit. + * If overflow occurs, result integer (incorrect) is still returned. + * + * Don't you dare use this function. + */ +static unsigned int _parse_integer(const char *s, + unsigned int base, + unsigned long long *p) +{ + unsigned long long res; + unsigned int rv; + + res = 0; + rv = 0; + while (1) { + unsigned int c = *s; + unsigned int lc = c | 0x20; /* don't tolower() this line */ + unsigned int val; + + if ('0' <= c && c <= '9') + val = c - '0'; + else if ('a' <= lc && lc <= 'f') + val = lc - 'a' + 10; + else + break; + + if (val >= base) + break; + /* + * Check for overflow only if we are within range of + * it in the max base we support (16) + */ + if (unlikely(res & (~0ull << 60))) { + if (res > __div_u64(ULLONG_MAX - val, base)) + rv |= KSTRTOX_OVERFLOW; + } + res = res * base + val; + rv++; + s++; + } + *p = res; + return rv; +} + +static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res) +{ + unsigned long long _res; + unsigned int rv; + + s = _parse_integer_fixup_radix(s, &base); + rv = _parse_integer(s, base, &_res); + if (rv & KSTRTOX_OVERFLOW) + return -ERANGE; + if (rv == 0) + return -EINVAL; + s += rv; + if (*s == '\n') + s++; + if (*s) + return -EINVAL; + *res = _res; + return 0; +} + +/** + * kstrtoull - convert a string to an unsigned long long + * @s: The start of the string. The string must be null-terminated, and may also + * include a single newline before its terminating null. The first character + * may also be a plus sign, but not a minus sign. + * @base: The number base to use. The maximum supported base is 16. If base is + * given as 0, then the base of the string is automatically detected with the + * conventional semantics - If it begins with 0x the number will be parsed as a + * hexadecimal (case insensitive), if it otherwise begins with 0, it will be + * parsed as an octal number. Otherwise it will be parsed as a decimal. + * @res: Where to write the result of the conversion on success. + * + * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. + * Used as a replacement for the obsolete simple_strtoull. Return code must + * be checked. + */ +int kstrtoull(const char *s, unsigned int base, unsigned long long *res) +{ + if (s[0] == '+') + s++; + return _kstrtoull(s, base, res); +} diff --git a/arch/x86/boot/string.h b/arch/x86/boot/string.h index 3d78e27077f4..38d8f2f5e47e 100644 --- a/arch/x86/boot/string.h +++ b/arch/x86/boot/string.h @@ -29,4 +29,5 @@ extern unsigned int atou(const char *s); extern unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base); +int kstrtoull(const char *s, unsigned int base, unsigned long long *res); #endif /* BOOT_STRING_H */ -- 2.20.1