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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4439FC433EF for ; Mon, 15 Nov 2021 16:55:44 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id EEBD560174 for ; Mon, 15 Nov 2021 16:55:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org EEBD560174 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A330F4B1BD; Mon, 15 Nov 2021 11:55:43 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VgiG-zOoTFdO; Mon, 15 Nov 2021 11:55:41 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A6ADD4B1D0; Mon, 15 Nov 2021 11:55:41 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id C5A424B150 for ; Mon, 15 Nov 2021 11:55:39 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EMBQVbBxNuzA for ; Mon, 15 Nov 2021 11:55:38 -0500 (EST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0F5E84B1E3 for ; Mon, 15 Nov 2021 11:55:38 -0500 (EST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C735C1063; Mon, 15 Nov 2021 08:55:37 -0800 (PST) Received: from monolith.localdoman (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 547953F766; Mon, 15 Nov 2021 08:55:36 -0800 (PST) From: Alexandru Elisei To: will@kernel.org, julien.thierry.kdev@gmail.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, maz@kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, mark.rutland@arm.com Subject: [PATCH kvmtool 7/9] util: Add cpulist_parse() Date: Mon, 15 Nov 2021 16:57:03 +0000 Message-Id: <20211115165705.195736-8-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165705.195736-1-alexandru.elisei@arm.com> References: <20211115165705.195736-1-alexandru.elisei@arm.com> MIME-Version: 1.0 X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Add the function cpulist_parse(), which creates a cpumask_t from a cpulist. The function will be necessary to parse the cpulist of CPUs associated with a particular PMU. Signed-off-by: Alexandru Elisei --- Makefile | 1 + include/linux/bitmap.h | 25 +++++ include/linux/bitops.h | 2 + include/linux/cpumask.h | 5 + include/linux/kernel.h | 1 + util/bitmap.c | 221 ++++++++++++++++++++++++++++++++++++++++ 6 files changed, 255 insertions(+) create mode 100644 util/bitmap.c diff --git a/Makefile b/Makefile index c7820e6a5200..3f65d6b0478d 100644 --- a/Makefile +++ b/Makefile @@ -88,6 +88,7 @@ OBJS += net/uip/buf.o OBJS += net/uip/csum.o OBJS += net/uip/dhcp.o OBJS += kvm-cmd.o +OBJS += util/bitmap.o OBJS += util/init.o OBJS += util/iovec.o OBJS += util/rbtree.o diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 33b24520a576..3221d06d9200 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -17,4 +17,29 @@ static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) memset(dst, 0, len); } +#ifdef __LITTLE_ENDIAN +#define BITMAP_MEM_ALIGNMENT 8 +#else +#define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long)) +#endif +#define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1) + +void __bitmap_set(unsigned long *map, unsigned int start, int len); + +static inline void bitmap_set(unsigned long *map, unsigned int start, + unsigned int nbits) +{ + if (__builtin_constant_p(nbits) && nbits == 1) + set_bit(start, map); + else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && + IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && + __builtin_constant_p(nbits & BITMAP_MEM_MASK) && + IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) + memset((char *)map + start / 8, 0xff, nbits / 8); + else + __bitmap_set(map, start, nbits); +} + +int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits); + #endif /* KVM__BITMAP_H */ diff --git a/include/linux/bitops.h b/include/linux/bitops.h index 56448b71ebbf..d8df5515ceb8 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -9,6 +9,8 @@ #define BITS_PER_BYTE 8 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) +#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) + static inline void set_bit(int nr, unsigned long *addr) { addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG); diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 36959885aeff..25c11b0361ec 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -30,4 +30,9 @@ static inline void cpumask_clear(cpumask_t *dstp) bitmap_zero(cpumask_bits(dstp), NR_CPUS); } +static inline int cpulist_parse(const char *buf, cpumask_t *dstp) +{ + return bitmap_parselist(buf, cpumask_bits(dstp), NR_CPUS); +} + #endif /* KVM__CPUMASK_H */ diff --git a/include/linux/kernel.h b/include/linux/kernel.h index f3240e09a321..0b9079f9c0bc 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -8,6 +8,7 @@ #define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1) #define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask)) +#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) #ifndef offsetof #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) diff --git a/util/bitmap.c b/util/bitmap.c new file mode 100644 index 000000000000..eef23d0f1845 --- /dev/null +++ b/util/bitmap.c @@ -0,0 +1,221 @@ +/* + * Taken from Linux kernel version v5.15. + */ +#include +#include +#include +#include + +#include +#include +#include + +/* + * Region 9-38:4/10 describes the following bitmap structure: + * 0 9 12 18 38 N + * .........****......****......****.................. + * ^ ^ ^ ^ ^ + * start off group_len end nbits + */ +struct region { + unsigned int start; + unsigned int off; + unsigned int group_len; + unsigned int end; + unsigned int nbits; +}; + +void __bitmap_set(unsigned long *map, unsigned int start, int len) +{ + unsigned long *p = map + BIT_WORD(start); + const unsigned int size = start + len; + int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); + unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); + + while (len - bits_to_set >= 0) { + *p |= mask_to_set; + len -= bits_to_set; + bits_to_set = BITS_PER_LONG; + mask_to_set = ~0UL; + p++; + } + if (len) { + mask_to_set &= BITMAP_LAST_WORD_MASK(size); + *p |= mask_to_set; + } +} + +static void bitmap_set_region(const struct region *r, unsigned long *bitmap) +{ + unsigned int start; + + for (start = r->start; start <= r->end; start += r->group_len) + bitmap_set(bitmap, start, min(r->end - start + 1, r->off)); +} + +static inline bool __end_of_region(char c) +{ + return isspace(c) || c == ','; +} + +static inline bool end_of_str(char c) +{ + return c == '\0' || c == '\n'; +} + +static inline bool end_of_region(char c) +{ + return __end_of_region(c) || end_of_str(c); +} + +/* + * The format allows commas and whitespaces at the beginning + * of the region. + */ +static const char *bitmap_find_region(const char *str) +{ + while (__end_of_region(*str)) + str++; + + return end_of_str(*str) ? NULL : str; +} + +static int bitmap_check_region(const struct region *r) +{ + if (r->start > r->end || r->group_len == 0 || r->off > r->group_len) + return -EINVAL; + + if (r->end >= r->nbits) + return -ERANGE; + + return 0; +} + +static const char *bitmap_getnum(const char *str, unsigned int *num, + unsigned int lastbit) +{ + unsigned long long n; + char *endptr; + + if (str[0] == 'N') { + *num = lastbit; + return str + 1; + } + + n = strtoll(str, &endptr, 10); + /* No digits found. */ + if (n == 0 && endptr == str) + return ERR_PTR(-EINVAL); + /* Check for overflows and negative numbers. */ + if (n == ULLONG_MAX || n != (unsigned long)n || n != (unsigned int)n) + return ERR_PTR(-EOVERFLOW); + + *num = n; + return endptr; +} + +static const char *bitmap_parse_region(const char *str, struct region *r) +{ + unsigned int lastbit = r->nbits - 1; + + if (!strncasecmp(str, "all", 3)) { + r->start = 0; + r->end = lastbit; + str += 3; + + goto check_pattern; + } + + str = bitmap_getnum(str, &r->start, lastbit); + if (IS_ERR(str)) + return str; + + if (end_of_region(*str)) + goto no_end; + + if (*str != '-') + return ERR_PTR(-EINVAL); + + str = bitmap_getnum(str + 1, &r->end, lastbit); + if (IS_ERR(str)) + return str; + +check_pattern: + if (end_of_region(*str)) + goto no_pattern; + + if (*str != ':') + return ERR_PTR(-EINVAL); + + str = bitmap_getnum(str + 1, &r->off, lastbit); + if (IS_ERR(str)) + return str; + + if (*str != '/') + return ERR_PTR(-EINVAL); + + return bitmap_getnum(str + 1, &r->group_len, lastbit); + +no_end: + r->end = r->start; +no_pattern: + r->off = r->end + 1; + r->group_len = r->end + 1; + + return end_of_str(*str) ? NULL : str; +} + +/** + * bitmap_parselist - convert list format ASCII string to bitmap + * @buf: read user string from this buffer; must be terminated + * with a \0 or \n. + * @maskp: write resulting mask here + * @nmaskbits: number of bits in mask to be written + * + * Input format is a comma-separated list of decimal numbers and + * ranges. Consecutively set bits are shown as two hyphen-separated + * decimal numbers, the smallest and largest bit numbers set in + * the range. + * Optionally each range can be postfixed to denote that only parts of it + * should be set. The range will divided to groups of specific size. + * From each group will be used only defined amount of bits. + * Syntax: range:used_size/group_size + * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 + * The value 'N' can be used as a dynamically substituted token for the + * maximum allowed value; i.e (nmaskbits - 1). Keep in mind that it is + * dynamic, so if system changes cause the bitmap width to change, such + * as more cores in a CPU list, then any ranges using N will also change. + * + * Returns: 0 on success, -errno on invalid input strings. Error values: + * + * - ``-EINVAL``: wrong region format + * - ``-EINVAL``: invalid character in string + * - ``-ERANGE``: bit number specified too large for mask + * - ``-EOVERFLOW``: integer overflow in the input parameters + */ +int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) +{ + struct region r; + long ret; + + r.nbits = nmaskbits; + bitmap_zero(maskp, r.nbits); + + while (buf) { + buf = bitmap_find_region(buf); + if (buf == NULL) + return 0; + + buf = bitmap_parse_region(buf, &r); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + ret = bitmap_check_region(&r); + if (ret) + return ret; + + bitmap_set_region(&r, maskp); + } + + return 0; +} -- 2.31.1 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B4FFC433F5 for ; Mon, 15 Nov 2021 16:59:23 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1AB0161BD2 for ; Mon, 15 Nov 2021 16:59:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1AB0161BD2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Cc:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=e3Y8p/A3uVWB2wl/XrOKGsOZLTws27pvYAsatmanXxM=; b=WossW7YiJimQVe FBRJZmrKnlTKkdYrpq9Gek4MDuIeVHbgUQGlm0TksYnQESFDnCII4pinaIP4uUWTVZZK8S4y7Ur5a CQ/hijyTHoIgsFb0qfZEmom+lwtYlGO3PPxoWF78t6XsV2obDrRL2WlE3bV3LbxGM/vt4ArGsro+y aOGdy9iDZ/cITLdBLN29TwuvYnroLFUxn9Cln/f6rFlQ8u7GQi9YHGYePUtmX3DmD3mCHtFcQ/lYX 7QfuAWqfqTwcvP6qbtydrfqupLD6hiY2SQB7WFMWHKr/TPyDCJT4M5lR1J0L+0Z9bZmLcv/3618N0 4EpV07RYl89nAkttkDDw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mmfJ0-00GRpp-Jw; Mon, 15 Nov 2021 16:58:06 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mmfGc-00GQd1-O7 for linux-arm-kernel@lists.infradead.org; Mon, 15 Nov 2021 16:55:40 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C735C1063; Mon, 15 Nov 2021 08:55:37 -0800 (PST) Received: from monolith.localdoman (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 547953F766; Mon, 15 Nov 2021 08:55:36 -0800 (PST) From: Alexandru Elisei To: will@kernel.org, julien.thierry.kdev@gmail.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, maz@kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, mark.rutland@arm.com Subject: [PATCH kvmtool 7/9] util: Add cpulist_parse() Date: Mon, 15 Nov 2021 16:57:03 +0000 Message-Id: <20211115165705.195736-8-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165705.195736-1-alexandru.elisei@arm.com> References: <20211115165705.195736-1-alexandru.elisei@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211115_085538_945294_C858344E X-CRM114-Status: GOOD ( 25.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add the function cpulist_parse(), which creates a cpumask_t from a cpulist. The function will be necessary to parse the cpulist of CPUs associated with a particular PMU. Signed-off-by: Alexandru Elisei --- Makefile | 1 + include/linux/bitmap.h | 25 +++++ include/linux/bitops.h | 2 + include/linux/cpumask.h | 5 + include/linux/kernel.h | 1 + util/bitmap.c | 221 ++++++++++++++++++++++++++++++++++++++++ 6 files changed, 255 insertions(+) create mode 100644 util/bitmap.c diff --git a/Makefile b/Makefile index c7820e6a5200..3f65d6b0478d 100644 --- a/Makefile +++ b/Makefile @@ -88,6 +88,7 @@ OBJS += net/uip/buf.o OBJS += net/uip/csum.o OBJS += net/uip/dhcp.o OBJS += kvm-cmd.o +OBJS += util/bitmap.o OBJS += util/init.o OBJS += util/iovec.o OBJS += util/rbtree.o diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 33b24520a576..3221d06d9200 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -17,4 +17,29 @@ static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) memset(dst, 0, len); } +#ifdef __LITTLE_ENDIAN +#define BITMAP_MEM_ALIGNMENT 8 +#else +#define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long)) +#endif +#define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1) + +void __bitmap_set(unsigned long *map, unsigned int start, int len); + +static inline void bitmap_set(unsigned long *map, unsigned int start, + unsigned int nbits) +{ + if (__builtin_constant_p(nbits) && nbits == 1) + set_bit(start, map); + else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && + IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && + __builtin_constant_p(nbits & BITMAP_MEM_MASK) && + IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) + memset((char *)map + start / 8, 0xff, nbits / 8); + else + __bitmap_set(map, start, nbits); +} + +int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits); + #endif /* KVM__BITMAP_H */ diff --git a/include/linux/bitops.h b/include/linux/bitops.h index 56448b71ebbf..d8df5515ceb8 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -9,6 +9,8 @@ #define BITS_PER_BYTE 8 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) +#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) + static inline void set_bit(int nr, unsigned long *addr) { addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG); diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 36959885aeff..25c11b0361ec 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -30,4 +30,9 @@ static inline void cpumask_clear(cpumask_t *dstp) bitmap_zero(cpumask_bits(dstp), NR_CPUS); } +static inline int cpulist_parse(const char *buf, cpumask_t *dstp) +{ + return bitmap_parselist(buf, cpumask_bits(dstp), NR_CPUS); +} + #endif /* KVM__CPUMASK_H */ diff --git a/include/linux/kernel.h b/include/linux/kernel.h index f3240e09a321..0b9079f9c0bc 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -8,6 +8,7 @@ #define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1) #define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask)) +#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) #ifndef offsetof #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) diff --git a/util/bitmap.c b/util/bitmap.c new file mode 100644 index 000000000000..eef23d0f1845 --- /dev/null +++ b/util/bitmap.c @@ -0,0 +1,221 @@ +/* + * Taken from Linux kernel version v5.15. + */ +#include +#include +#include +#include + +#include +#include +#include + +/* + * Region 9-38:4/10 describes the following bitmap structure: + * 0 9 12 18 38 N + * .........****......****......****.................. + * ^ ^ ^ ^ ^ + * start off group_len end nbits + */ +struct region { + unsigned int start; + unsigned int off; + unsigned int group_len; + unsigned int end; + unsigned int nbits; +}; + +void __bitmap_set(unsigned long *map, unsigned int start, int len) +{ + unsigned long *p = map + BIT_WORD(start); + const unsigned int size = start + len; + int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); + unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); + + while (len - bits_to_set >= 0) { + *p |= mask_to_set; + len -= bits_to_set; + bits_to_set = BITS_PER_LONG; + mask_to_set = ~0UL; + p++; + } + if (len) { + mask_to_set &= BITMAP_LAST_WORD_MASK(size); + *p |= mask_to_set; + } +} + +static void bitmap_set_region(const struct region *r, unsigned long *bitmap) +{ + unsigned int start; + + for (start = r->start; start <= r->end; start += r->group_len) + bitmap_set(bitmap, start, min(r->end - start + 1, r->off)); +} + +static inline bool __end_of_region(char c) +{ + return isspace(c) || c == ','; +} + +static inline bool end_of_str(char c) +{ + return c == '\0' || c == '\n'; +} + +static inline bool end_of_region(char c) +{ + return __end_of_region(c) || end_of_str(c); +} + +/* + * The format allows commas and whitespaces at the beginning + * of the region. + */ +static const char *bitmap_find_region(const char *str) +{ + while (__end_of_region(*str)) + str++; + + return end_of_str(*str) ? NULL : str; +} + +static int bitmap_check_region(const struct region *r) +{ + if (r->start > r->end || r->group_len == 0 || r->off > r->group_len) + return -EINVAL; + + if (r->end >= r->nbits) + return -ERANGE; + + return 0; +} + +static const char *bitmap_getnum(const char *str, unsigned int *num, + unsigned int lastbit) +{ + unsigned long long n; + char *endptr; + + if (str[0] == 'N') { + *num = lastbit; + return str + 1; + } + + n = strtoll(str, &endptr, 10); + /* No digits found. */ + if (n == 0 && endptr == str) + return ERR_PTR(-EINVAL); + /* Check for overflows and negative numbers. */ + if (n == ULLONG_MAX || n != (unsigned long)n || n != (unsigned int)n) + return ERR_PTR(-EOVERFLOW); + + *num = n; + return endptr; +} + +static const char *bitmap_parse_region(const char *str, struct region *r) +{ + unsigned int lastbit = r->nbits - 1; + + if (!strncasecmp(str, "all", 3)) { + r->start = 0; + r->end = lastbit; + str += 3; + + goto check_pattern; + } + + str = bitmap_getnum(str, &r->start, lastbit); + if (IS_ERR(str)) + return str; + + if (end_of_region(*str)) + goto no_end; + + if (*str != '-') + return ERR_PTR(-EINVAL); + + str = bitmap_getnum(str + 1, &r->end, lastbit); + if (IS_ERR(str)) + return str; + +check_pattern: + if (end_of_region(*str)) + goto no_pattern; + + if (*str != ':') + return ERR_PTR(-EINVAL); + + str = bitmap_getnum(str + 1, &r->off, lastbit); + if (IS_ERR(str)) + return str; + + if (*str != '/') + return ERR_PTR(-EINVAL); + + return bitmap_getnum(str + 1, &r->group_len, lastbit); + +no_end: + r->end = r->start; +no_pattern: + r->off = r->end + 1; + r->group_len = r->end + 1; + + return end_of_str(*str) ? NULL : str; +} + +/** + * bitmap_parselist - convert list format ASCII string to bitmap + * @buf: read user string from this buffer; must be terminated + * with a \0 or \n. + * @maskp: write resulting mask here + * @nmaskbits: number of bits in mask to be written + * + * Input format is a comma-separated list of decimal numbers and + * ranges. Consecutively set bits are shown as two hyphen-separated + * decimal numbers, the smallest and largest bit numbers set in + * the range. + * Optionally each range can be postfixed to denote that only parts of it + * should be set. The range will divided to groups of specific size. + * From each group will be used only defined amount of bits. + * Syntax: range:used_size/group_size + * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 + * The value 'N' can be used as a dynamically substituted token for the + * maximum allowed value; i.e (nmaskbits - 1). Keep in mind that it is + * dynamic, so if system changes cause the bitmap width to change, such + * as more cores in a CPU list, then any ranges using N will also change. + * + * Returns: 0 on success, -errno on invalid input strings. Error values: + * + * - ``-EINVAL``: wrong region format + * - ``-EINVAL``: invalid character in string + * - ``-ERANGE``: bit number specified too large for mask + * - ``-EOVERFLOW``: integer overflow in the input parameters + */ +int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) +{ + struct region r; + long ret; + + r.nbits = nmaskbits; + bitmap_zero(maskp, r.nbits); + + while (buf) { + buf = bitmap_find_region(buf); + if (buf == NULL) + return 0; + + buf = bitmap_parse_region(buf, &r); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + ret = bitmap_check_region(&r); + if (ret) + return ret; + + bitmap_set_region(&r, maskp); + } + + return 0; +} -- 2.31.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel