From 69324b8f48339de2f90fdf2f774687fc6c47629a Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 28 Dec 2018 00:35:01 -0800 Subject: [PATCH] mm, devm_memremap_pages: add MEMORY_DEVICE_PRIVATE support MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 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. [jglisse@redhat.com: call move_pfn_range_to_zone for MEMORY_DEVICE_PRIVATE] Link: http://lkml.kernel.org/r/154275559036.76910.12434636179931292607.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Reviewed-by: Jérôme Glisse Acked-by: Christoph Hellwig Reported-by: Logan Gunthorpe Reviewed-by: Logan Gunthorpe Cc: Balbir Singh Cc: Michal Hocko Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/memremap.c | 53 +++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 41 insertions(+), 12 deletions(-) diff --git a/kernel/memremap.c b/kernel/memremap.c index 5e45f0c..3eef989 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -98,9 +98,15 @@ 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); @@ -187,17 +193,40 @@ 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; -- 2.7.4