From patchwork Thu Mar 25 11:53:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12163889 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=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,URIBL_RED 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 F38A2C433C1 for ; Thu, 25 Mar 2021 11:54:21 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 734BA61A0A for ; Thu, 25 Mar 2021 11:54:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 734BA61A0A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 084706B0083; Thu, 25 Mar 2021 07:54:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 047BF6B0085; Thu, 25 Mar 2021 07:54:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DDE4E6B0087; Thu, 25 Mar 2021 07:54:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0049.hostedemail.com [216.40.44.49]) by kanga.kvack.org (Postfix) with ESMTP id C29B16B0083 for ; Thu, 25 Mar 2021 07:54:20 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 816DC80DD077 for ; Thu, 25 Mar 2021 11:54:20 +0000 (UTC) X-FDA: 77958238680.27.3050D46 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf10.hostedemail.com (Postfix) with ESMTP id 7C5EC40002D0 for ; Thu, 25 Mar 2021 11:54:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616673259; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=57Syy87RcK+AlwebrqRsu9Z8bLmvqowWF6LlY9KkoZA=; b=hDwpSamA++8q7bIhzMpF7VL5SSiG04avmF3doPbLRgOB7S+bZ0nVULdzwAHe1qfG3DitCl lkid/629SrVeFz/bAjaKnnKWsYltBzvzi/y/a5yRpzLFNqTVKyCaLMMfBH/RPqM2XEGNyC evDj87hoD/uU2p4iPNR7KdnyL+iAZEM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-49-VJw28n4xPeac7oyeC4M4mQ-1; Thu, 25 Mar 2021 07:54:17 -0400 X-MC-Unique: VJw28n4xPeac7oyeC4M4mQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 921BA81624; Thu, 25 Mar 2021 11:54:14 +0000 (UTC) Received: from t480s.redhat.com (ovpn-115-72.ams2.redhat.com [10.36.115.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id CB53060861; Thu, 25 Mar 2021 11:54:04 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, David Hildenbrand , Dan Williams , Andy Shevchenko , Andrew Morton , Greg Kroah-Hartman , Daniel Vetter , Mauro Carvalho Chehab , Dave Young , Baoquan He , Vivek Goyal , Dave Hansen , Keith Busch , Michal Hocko , Qian Cai , Oscar Salvador , Eric Biederman , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Tom Lendacky , Brijesh Singh , x86@kernel.org, kexec@lists.infradead.org Subject: [PATCH v2 3/3] kernel/resource: remove first_lvl / siblings_only logic Date: Thu, 25 Mar 2021 12:53:26 +0100 Message-Id: <20210325115326.7826-4-david@redhat.com> In-Reply-To: <20210325115326.7826-1-david@redhat.com> References: <20210325115326.7826-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 7C5EC40002D0 X-Stat-Signature: c9epqzafohh38az6rht8hxkk3gwbtfec Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf10; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=216.205.24.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616673258-894818 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: All functions that search for IORESOURCE_SYSTEM_RAM or IORESOURCE_MEM resources now properly consider the whole resource tree, not just the first level. Let's drop the unused first_lvl / siblings_only logic. Remove documentation that indicates that some functions behave differently, all consider the full resource tree now. Reviewed-by: Dan Williams Reviewed-by: Andy Shevchenko Cc: Andrew Morton Cc: Greg Kroah-Hartman Cc: Dan Williams Cc: Daniel Vetter Cc: Andy Shevchenko Cc: Mauro Carvalho Chehab Cc: Dave Young Cc: Baoquan He Cc: Vivek Goyal Cc: Dave Hansen Cc: Keith Busch Cc: Michal Hocko Cc: Qian Cai Cc: Oscar Salvador Cc: Eric Biederman Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Tom Lendacky Cc: Brijesh Singh Cc: x86@kernel.org Cc: kexec@lists.infradead.org Signed-off-by: David Hildenbrand --- kernel/resource.c | 45 ++++++++++++--------------------------------- 1 file changed, 12 insertions(+), 33 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 16e0c7e8ed24..7e00239a023a 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -64,12 +64,8 @@ static DEFINE_RWLOCK(resource_lock); static struct resource *bootmem_resource_free; static DEFINE_SPINLOCK(bootmem_resource_lock); -static struct resource *next_resource(struct resource *p, bool sibling_only) +static struct resource *next_resource(struct resource *p) { - /* Caller wants to traverse through siblings only */ - if (sibling_only) - return p->sibling; - if (p->child) return p->child; while (!p->sibling && p->parent) @@ -81,7 +77,7 @@ static void *r_next(struct seq_file *m, void *v, loff_t *pos) { struct resource *p = v; (*pos)++; - return (void *)next_resource(p, false); + return (void *)next_resource(p); } #ifdef CONFIG_PROC_FS @@ -330,14 +326,10 @@ EXPORT_SYMBOL(release_resource); * of the resource that's within [@start..@end]; if none is found, returns * -ENODEV. Returns -EINVAL for invalid parameters. * - * This function walks the whole tree and not just first level children - * unless @first_lvl is true. - * * @start: start address of the resource searched for * @end: end address of same resource * @flags: flags which the resource must have * @desc: descriptor the resource must have - * @first_lvl: walk only the first level children, if set * @res: return ptr, if resource found * * The caller must specify @start, @end, @flags, and @desc @@ -345,9 +337,8 @@ EXPORT_SYMBOL(release_resource); */ static int find_next_iomem_res(resource_size_t start, resource_size_t end, unsigned long flags, unsigned long desc, - bool first_lvl, struct resource *res) + struct resource *res) { - bool siblings_only = true; struct resource *p; if (!res) @@ -358,7 +349,7 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end, read_lock(&resource_lock); - for (p = iomem_resource.child; p; p = next_resource(p, siblings_only)) { + for (p = iomem_resource.child; p; p = next_resource(p)) { /* If we passed the resource we are looking for, stop */ if (p->start > end) { p = NULL; @@ -369,13 +360,6 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end, if (p->end < start) continue; - /* - * Now that we found a range that matches what we look for, - * check the flags and the descriptor. If we were not asked to - * use only the first level, start looking at children as well. - */ - siblings_only = first_lvl; - if ((p->flags & flags) != flags) continue; if ((desc != IORES_DESC_NONE) && (desc != p->desc)) @@ -402,14 +386,14 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end, static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, unsigned long flags, unsigned long desc, - bool first_lvl, void *arg, + void *arg, int (*func)(struct resource *, void *)) { struct resource res; int ret = -EINVAL; while (start < end && - !find_next_iomem_res(start, end, flags, desc, first_lvl, &res)) { + !find_next_iomem_res(start, end, flags, desc, &res)) { ret = (*func)(&res, arg); if (ret) break; @@ -431,7 +415,6 @@ static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, * @arg: function argument for the callback @func * @func: callback function that is called for each qualifying resource area * - * This walks through whole tree and not just first level children. * All the memory ranges which overlap start,end and also match flags and * desc are valid candidates. * @@ -441,7 +424,7 @@ static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { - return __walk_iomem_res_desc(start, end, flags, desc, false, arg, func); + return __walk_iomem_res_desc(start, end, flags, desc, arg, func); } EXPORT_SYMBOL_GPL(walk_iomem_res_desc); @@ -457,8 +440,8 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, { unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, false, - arg, func); + return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, arg, + func); } /* @@ -470,17 +453,14 @@ int walk_mem_res(u64 start, u64 end, void *arg, { unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; - return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, false, - arg, func); + return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, arg, + func); } /* * This function calls the @func callback against all memory ranges of type * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. * It is to be used only for System RAM. - * - * This will find System RAM ranges that are children of top-level resources - * in addition to top-level System RAM resources. */ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)) @@ -495,8 +475,7 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; while (start < end && - !find_next_iomem_res(start, end, flags, IORES_DESC_NONE, - false, &res)) { + !find_next_iomem_res(start, end, flags, IORES_DESC_NONE, &res)) { pfn = PFN_UP(res.start); end_pfn = PFN_DOWN(res.end + 1); if (end_pfn > pfn)