diff mbox series

[v4,2/4] memblock: update initialization of reserved pages

Message ID 20210511100550.28178-3-rppt@kernel.org (mailing list archive)
State New
Headers show
Series arm64: drop pfn_valid_within() and simplify pfn_valid() | expand

Commit Message

Mike Rapoport May 11, 2021, 10:05 a.m. UTC
From: Mike Rapoport <rppt@linux.ibm.com>

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.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 include/linux/memblock.h |  4 +++-
 mm/memblock.c            | 28 ++++++++++++++++++++++++++--
 2 files changed, 29 insertions(+), 3 deletions(-)

Comments

Ard Biesheuvel May 11, 2021, 10:23 a.m. UTC | #1
On Tue, 11 May 2021 at 12:06, Mike Rapoport <rppt@kernel.org> wrote:
>
> From: Mike Rapoport <rppt@linux.ibm.com>
>
> 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.
>
> 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>

> ---
>  include/linux/memblock.h |  4 +++-
>  mm/memblock.c            | 28 ++++++++++++++++++++++++++--
>  2 files changed, 29 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index 5984fff3f175..1b4c97c151ae 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -30,7 +30,9 @@ extern unsigned long long max_possible_pfn;
>   * @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 */
> diff --git a/mm/memblock.c b/mm/memblock.c
> index afaefa8fc6ab..3abf2c3fea7f 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -906,6 +906,11 @@ int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
>   * @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_memory_core(phys_addr_t start,
>         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_memory_core_early(void)
>
>         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
> --
> 2.28.0
>
diff mbox series

Patch

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 5984fff3f175..1b4c97c151ae 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -30,7 +30,9 @@  extern unsigned long long max_possible_pfn;
  * @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 */
diff --git a/mm/memblock.c b/mm/memblock.c
index afaefa8fc6ab..3abf2c3fea7f 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -906,6 +906,11 @@  int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
  * @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_memory_core(phys_addr_t start,
 	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_memory_core_early(void)
 
 	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