Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933944AbcCISyr (ORCPT ); Wed, 9 Mar 2016 13:54:47 -0500 Received: from g9t5008.houston.hp.com ([15.240.92.66]:34074 "EHLO g9t5008.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933900AbcCISye (ORCPT ); Wed, 9 Mar 2016 13:54:34 -0500 From: Toshi Kani To: mingo@kernel.org, bp@suse.de, dan.j.williams@intel.com, rjw@rjwysocki.net, akpm@linux-foundation.org Cc: linux-nvdimm@ml01.01.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Toshi Kani Subject: [PATCH v3 1/4] resource: Change __request_region to inherit from immediate parent Date: Wed, 9 Mar 2016 12:47:03 -0700 Message-Id: <1457552826-13987-1-git-send-email-toshi.kani@hpe.com> X-Mailer: git-send-email 2.5.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1935 Lines: 56 __request_region() sets 'flags' of a new resource from @parent as it inherits the parent's attribute. When a target resource has a conflict, this function inserts the new resource entry under the conflicted entry by updating @parent. In this case, the new resource entry needs to inherit attribute from the updated parent. This conflict is a typical case since __request_region() is used to allocate a new resource from a specific resource range. For instance, request_mem_region() calls __request_region() with @parent set to &iomem_resource, which is the root entry of the whole iomem range. When this request results in inserting a new entry "DEV-A" under "BUS-1", "DEV-A" needs to inherit from the immediate parent "BUS-1" as it holds specific attribute for the range. root (&iomem_resource) : + "BUS-1" + "DEV-A" Change __request_region() to set 'flags' and 'desc' of a new entry from the immediate parent. Signed-off-by: Toshi Kani Cc: Ingo Molnar Cc: Borislav Petkov Cc: Andrew Morton Cc: Dan Williams --- kernel/resource.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 4d46605..5a56e8f 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -1085,15 +1085,16 @@ struct resource * __request_region(struct resource *parent, res->name = name; res->start = start; res->end = start + n - 1; - res->flags = resource_type(parent) | resource_ext_type(parent); - res->flags |= IORESOURCE_BUSY | flags; - res->desc = IORES_DESC_NONE; write_lock(&resource_lock); for (;;) { struct resource *conflict; + res->flags = resource_type(parent) | resource_ext_type(parent); + res->flags |= IORESOURCE_BUSY | flags; + res->desc = parent->desc; + conflict = __request_resource(parent, res); if (!conflict) break;