+ memblock-update-initialization-of-reserved-pages.patch added to -mm tree

+ memblock-update-initialization-of-reserved-pages.patch added to -mm tree

[akpm]

The patch titled
     Subject: memblock: update initialization of reserved pages
has been added to the -mm tree.  Its filename is
     memblock-update-initialization-of-reserved-pages.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/memblock-update-initialization-of-reserved-pages.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/memblock-update-initialization-of-reserved-pages.patch

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------------------------------------------------------
From: Mike Rapoport <rppt@linux.ibm.com>
Subject: memblock: update initialization of reserved pages

The struct pages representing a reserved memory region are initialized
using reserve_bootmem_range() function.  This function is called for each
reserved region just before the memory is freed from memblock to the buddy
page allocator.

The struct pages for MEMBLOCK_NOMAP regions are kept with the default
values set by the memory map initialization which makes it necessary to
have a special treatment for such pages in pfn_valid() and
pfn_valid_within().

Split out initialization of the reserved pages to a function with a
meaningful name and treat the MEMBLOCK_NOMAP regions the same way as the
reserved regions and mark struct pages for the NOMAP regions as
PageReserved.

Link: https://lkml.kernel.org/r/20210511100550.28178-3-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/memblock.h |    4 +++-
 mm/memblock.c            |   28 ++++++++++++++++++++++++++--
 2 files changed, 29 insertions(+), 3 deletions(-)

--- a/include/linux/memblock.h~memblock-update-initialization-of-reserved-pages
+++ a/include/linux/memblock.h
@@ -30,7 +30,9 @@ extern unsigned long long max_possible_p
  * @MEMBLOCK_NONE: no special request
  * @MEMBLOCK_HOTPLUG: hotpluggable region
  * @MEMBLOCK_MIRROR: mirrored region
- * @MEMBLOCK_NOMAP: don't add to kernel direct mapping
+ * @MEMBLOCK_NOMAP: don't add to kernel direct mapping and treat as
+ * reserved in the memory map; refer to memblock_mark_nomap() description
+ * for further details
  */
 enum memblock_flags {
 	MEMBLOCK_NONE		= 0x0,	/* No special request */
--- a/mm/memblock.c~memblock-update-initialization-of-reserved-pages
+++ a/mm/memblock.c
@@ -906,6 +906,11 @@ int __init_memblock memblock_mark_mirror
  * @base: the base phys addr of the region
  * @size: the size of the region
  *
+ * The memory regions marked with %MEMBLOCK_NOMAP will not be added to the
+ * direct mapping of the physical memory. These regions will still be
+ * covered by the memory map. The struct page representing NOMAP memory
+ * frames in the memory map will be PageReserved()
+ *
  * Return: 0 on success, -errno on failure.
  */
 int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)
@@ -2002,6 +2007,26 @@ static unsigned long __init __free_memor
 	return end_pfn - start_pfn;
 }
 
+static void __init memmap_init_reserved_pages(void)
+{
+	struct memblock_region *region;
+	phys_addr_t start, end;
+	u64 i;
+
+	/* initialize struct pages for the reserved regions */
+	for_each_reserved_mem_range(i, &start, &end)
+		reserve_bootmem_region(start, end);
+
+	/* and also treat struct pages for the NOMAP regions as PageReserved */
+	for_each_mem_region(region) {
+		if (memblock_is_nomap(region)) {
+			start = region->base;
+			end = start + region->size;
+			reserve_bootmem_region(start, end);
+		}
+	}
+}
+
 static unsigned long __init free_low_memory_core_early(void)
 {
 	unsigned long count = 0;
@@ -2010,8 +2035,7 @@ static unsigned long __init free_low_mem
 
 	memblock_clear_hotplug(0, -1);
 
-	for_each_reserved_mem_range(i, &start, &end)
-		reserve_bootmem_region(start, end);
+	memmap_init_reserved_pages();
 
 	/*
 	 * We need to use NUMA_NO_NODE instead of NODE_DATA(0)->node_id
_

Patches currently in -mm which might be from rppt@linux.ibm.com are

mm-mmzoneh-simplify-is_highmem_idx.patch
docs-procrst-meminfo-briefly-describe-gaps-in-memory-accounting.patch
include-linux-mmzoneh-add-documentation-for-pfn_valid.patch
memblock-update-initialization-of-reserved-pages.patch
arm64-decouple-check-whether-pfn-is-in-linear-map-from-pfn_valid.patch
arm64-drop-pfn_valid_within-and-simplify-pfn_valid.patch
mmap-make-mlock_future_check-global.patch
riscv-kconfig-make-direct-map-manipulation-options-depend-on-mmu.patch
set_memory-allow-set_direct_map__noflush-for-multiple-pages.patch
set_memory-allow-querying-whether-set_direct_map_-is-actually-enabled.patch
mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas.patch
mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix.patch
mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-2.patch
mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-3.patch
pm-hibernate-disable-when-there-are-active-secretmem-users.patch
arch-mm-wire-up-memfd_secret-system-call-where-relevant.patch
arch-mm-wire-up-memfd_secret-system-call-where-relevant-fix.patch
secretmem-test-add-basic-selftest-for-memfd_secret2.patch
secretmem-test-add-basic-selftest-for-memfd_secret2-fix.patch