From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751932AbdKVCvW (ORCPT ); Tue, 21 Nov 2017 21:51:22 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:56653 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751778AbdKVCUW (ORCPT ); Tue, 21 Nov 2017 21:20:22 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Arnd Bergmann" , "Joe Perches" , "Linus Torvalds" , "Thierry Reding" , "Greg Kroah-Hartman" Date: Wed, 22 Nov 2017 01:58:12 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 011/133] asm/sections: add helpers to check for section data In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.51-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Thierry Reding commit 979559362516bb0f5424505c607210ac054e30ae upstream. Add a helper to check if an object (given an address and a size) is part of a section (given beginning and end addresses). For convenience, also provide a helper that performs this check for __init data using the __init_begin and __init_end limits. Signed-off-by: Thierry Reding Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- include/asm-generic/sections.h | 65 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) --- a/include/asm-generic/sections.h +++ b/include/asm-generic/sections.h @@ -4,6 +4,7 @@ /* References to section boundaries */ #include +#include /* * Usage guidelines: @@ -63,4 +64,68 @@ static inline int arch_is_kernel_data(un } #endif +/** + * memory_contains - checks if an object is contained within a memory region + * @begin: virtual address of the beginning of the memory region + * @end: virtual address of the end of the memory region + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if the object specified by @virt and @size is entirely + * contained within the memory region defined by @begin and @end, false + * otherwise. + */ +static inline bool memory_contains(void *begin, void *end, void *virt, + size_t size) +{ + return virt >= begin && virt + size <= end; +} + +/** + * memory_intersects - checks if the region occupied by an object intersects + * with another memory region + * @begin: virtual address of the beginning of the memory regien + * @end: virtual address of the end of the memory region + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if an object's memory region, specified by @virt and @size, + * intersects with the region specified by @begin and @end, false otherwise. + */ +static inline bool memory_intersects(void *begin, void *end, void *virt, + size_t size) +{ + void *vend = virt + size; + + return (virt >= begin && virt < end) || (vend >= begin && vend < end); +} + +/** + * init_section_contains - checks if an object is contained within the init + * section + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if the object specified by @virt and @size is entirely + * contained within the init section, false otherwise. + */ +static inline bool init_section_contains(void *virt, size_t size) +{ + return memory_contains(__init_begin, __init_end, virt, size); +} + +/** + * init_section_intersects - checks if the region occupied by an object + * intersects with the init section + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if an object's memory region, specified by @virt and @size, + * intersects with the init section, false otherwise. + */ +static inline bool init_section_intersects(void *virt, size_t size) +{ + return memory_intersects(__init_begin, __init_end, virt, size); +} + #endif /* _ASM_GENERIC_SECTIONS_H_ */