From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by kanga.kvack.org (Postfix) with ESMTP id 9E9F08E0001 for ; Tue, 18 Sep 2018 16:34:37 -0400 (EDT) Received: by mail-qk1-f198.google.com with SMTP id w126-v6so2249157qka.11 for ; Tue, 18 Sep 2018 13:34:37 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id l1-v6si1221195qtb.119.2018.09.18.13.34.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 18 Sep 2018 13:34:36 -0700 (PDT) Date: Tue, 18 Sep 2018 16:34:32 -0400 From: Jerome Glisse Subject: Re: [PATCH v5 4/7] mm, devm_memremap_pages: Add MEMORY_DEVICE_PRIVATE support Message-ID: <20180918203432.GD14689@redhat.com> References: <153680531988.453305.8080706591516037706.stgit@dwillia2-desk3.amr.corp.intel.com> <153680534246.453305.10522027577023444732.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <153680534246.453305.10522027577023444732.stgit@dwillia2-desk3.amr.corp.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Dan Williams Cc: akpm@linux-foundation.org, Christoph Hellwig , Logan Gunthorpe , alexander.h.duyck@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Below is v2 of this patch with v2 it works properly: From: Dan Williams Date: Wed, 12 Sep 2018 19:22:22 -0700 Subject: [PATCH] mm, devm_memremap_pages: Add MEMORY_DEVICE_PRIVATE support v2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In preparation for consolidating all ZONE_DEVICE enabling via devm_memremap_pages(), teach it how to handle the constraints of MEMORY_DEVICE_PRIVATE ranges. Changed since v1: - move_pfn_range_to_zone() for private device memory too Cc: Christoph Hellwig Reviewed-by: Jerome Glisse Reported-by: Logan Gunthorpe Reviewed-by: Logan Gunthorpe Signed-off-by: Dan Williams --- kernel/memremap.c | 53 ++++++++++++++++++++++++++++++++++++----------- 1 file changed, 41 insertions(+), 12 deletions(-) diff --git a/kernel/memremap.c b/kernel/memremap.c index 5b3b6f23fd35..adba623a25f4 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -132,9 +132,15 @@ static void devm_memremap_pages_release(void *data) - align_start; mem_hotplug_begin(); - arch_remove_memory(align_start, align_size, pgmap->altmap_valid ? - &pgmap->altmap : NULL); - kasan_remove_zero_shadow(__va(align_start), align_size); + if (pgmap->type == MEMORY_DEVICE_PRIVATE) { + pfn = align_start >> PAGE_SHIFT; + __remove_pages(page_zone(pfn_to_page(pfn)), pfn, + align_size >> PAGE_SHIFT, NULL); + } else { + arch_remove_memory(align_start, align_size, + pgmap->altmap_valid ? &pgmap->altmap : NULL); + kasan_remove_zero_shadow(__va(align_start), align_size); + } mem_hotplug_done(); untrack_pfn(NULL, PHYS_PFN(align_start), align_size); @@ -234,17 +240,40 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap, goto err_pfn_remap; mem_hotplug_begin(); - error = kasan_add_zero_shadow(__va(align_start), align_size); - if (error) { - mem_hotplug_done(); - goto err_kasan; + + /* + * For device private memory we call add_pages() as we only need to + * allocate and initialize struct page for the device memory. More- + * over the device memory is un-accessible thus we do not want to + * create a linear mapping for the memory like arch_add_memory() + * would do. + * + * For all other device memory types, which are accessible by + * the CPU, we do want the linear mapping and thus use + * arch_add_memory(). + */ + if (pgmap->type == MEMORY_DEVICE_PRIVATE) { + error = add_pages(nid, align_start >> PAGE_SHIFT, + align_size >> PAGE_SHIFT, NULL, false); + } else { + error = kasan_add_zero_shadow(__va(align_start), align_size); + if (error) { + mem_hotplug_done(); + goto err_kasan; + } + + error = arch_add_memory(nid, align_start, align_size, altmap, + false); + } + + if (!error) { + struct zone *zone; + + zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE]; + move_pfn_range_to_zone(zone, align_start >> PAGE_SHIFT, + align_size >> PAGE_SHIFT, altmap); } - error = arch_add_memory(nid, align_start, align_size, altmap, false); - if (!error) - move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], - align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT, altmap); mem_hotplug_done(); if (error) goto err_add_memory; -- 2.17.1