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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 42912C433ED for ; Fri, 7 May 2021 01:05:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E04A2613C8 for ; Fri, 7 May 2021 01:05:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E04A2613C8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6C65E6B00C9; Thu, 6 May 2021 21:05:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 64CBB6B00CA; Thu, 6 May 2021 21:05:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4EDE56B00CB; Thu, 6 May 2021 21:05:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0199.hostedemail.com [216.40.44.199]) by kanga.kvack.org (Postfix) with ESMTP id 2FA5E6B00C9 for ; Thu, 6 May 2021 21:05:26 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id EB3875832 for ; Fri, 7 May 2021 01:05:25 +0000 (UTC) X-FDA: 78112641810.28.087ED60 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf21.hostedemail.com (Postfix) with ESMTP id 31911E000120 for ; Fri, 7 May 2021 01:05:21 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 69B0E61289; Fri, 7 May 2021 01:05:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1620349524; bh=XAQQ8XwILTG/INR9nzM1dESbW0zYjavvpuimq4NvWpc=; h=Date:From:To:Subject:In-Reply-To:From; b=am9WsPI4Oiwy3Cnmb7jisDGkZpTM3zpnOegNl5sifr8ySI+VwhS7p4OpoOzwoBRtj KJ0R+rnDgmN6jrpqGP/WQezE9eTwZoVWGoEVuH6+KL3rqvjbEVapzyAkfqEmOzW5XN Zc1nSuP41nwzfqF9cCpJ3++S8zalOH/9kFi/yLSM= Date: Thu, 06 May 2021 18:05:24 -0700 From: Andrew Morton To: akpm@linux-foundation.org, apopple@nvidia.com, bsingharora@gmail.com, dan.j.williams@intel.com, daniel.vetter@ffwll.ch, david@redhat.com, gregkh@linuxfoundation.org, jglisse@redhat.com, jhubbard@nvidia.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, smuchun@gmail.com, torvalds@linux-foundation.org Subject: [patch 64/91] kernel/resource: allow region_intersects users to hold resource_lock Message-ID: <20210507010524.md9CmXvZW%akpm@linux-foundation.org> In-Reply-To: <20210506180126.03e1baee7ca52bedb6cc6003@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=am9WsPI4; dmarc=none; spf=pass (imf21.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Stat-Signature: u4j91dz9juh71bn8rqiuwa44mey5ic5q X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 31911E000120 Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf21; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1620349521-656270 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Alistair Popple Subject: kernel/resource: allow region_intersects users to hold resource_lock Introduce a version of region_intersects() that can be called with the resource_lock already held. This is used in a future fix to __request_free_mem_region(). [akpm@linux-foundation.org: make __region_intersects static] Link: https://lkml.kernel.org/r/20210419070109.4780-1-apopple@nvidia.com Signed-off-by: Alistair Popple Cc: David Hildenbrand Cc: Daniel Vetter Cc: Dan Williams Cc: Greg Kroah-Hartman Cc: John Hubbard Cc: Jerome Glisse Cc: Balbir Singh Cc: Muchun Song Signed-off-by: Andrew Morton --- kernel/resource.c | 52 ++++++++++++++++++++++++++------------------ 1 file changed, 31 insertions(+), 21 deletions(-) --- a/kernel/resource.c~kernel-resource-allow-region_intersects-users-to-hold-resource_lock +++ a/kernel/resource.c @@ -502,6 +502,34 @@ int __weak page_is_ram(unsigned long pfn } EXPORT_SYMBOL_GPL(page_is_ram); +static int __region_intersects(resource_size_t start, size_t size, + unsigned long flags, unsigned long desc) +{ + struct resource res; + int type = 0; int other = 0; + struct resource *p; + + res.start = start; + res.end = start + size - 1; + + for (p = iomem_resource.child; p ; p = p->sibling) { + bool is_type = (((p->flags & flags) == flags) && + ((desc == IORES_DESC_NONE) || + (desc == p->desc))); + + if (resource_overlaps(p, &res)) + is_type ? type++ : other++; + } + + if (type == 0) + return REGION_DISJOINT; + + if (other == 0) + return REGION_INTERSECTS; + + return REGION_MIXED; +} + /** * region_intersects() - determine intersection of region with known resources * @start: region start address @@ -525,31 +553,13 @@ EXPORT_SYMBOL_GPL(page_is_ram); int region_intersects(resource_size_t start, size_t size, unsigned long flags, unsigned long desc) { - struct resource res; - int type = 0; int other = 0; - struct resource *p; - - res.start = start; - res.end = start + size - 1; + int ret; read_lock(&resource_lock); - for (p = iomem_resource.child; p ; p = p->sibling) { - bool is_type = (((p->flags & flags) == flags) && - ((desc == IORES_DESC_NONE) || - (desc == p->desc))); - - if (resource_overlaps(p, &res)) - is_type ? type++ : other++; - } + ret = __region_intersects(start, size, flags, desc); read_unlock(&resource_lock); - if (type == 0) - return REGION_DISJOINT; - - if (other == 0) - return REGION_INTERSECTS; - - return REGION_MIXED; + return ret; } EXPORT_SYMBOL_GPL(region_intersects); _