[PATCH v7 02/12] mm/sparsemem: Introduce common definitions for the size and mask of a section

From: Dan Williams
Date: Thu May 02 2019 - 02:09:38 EST


Up-level the local section size and mask from kernel/memremap.c to
global definitions. These will be used by the new sub-section hotplug
support.

Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: JÃrÃme Glisse <jglisse@xxxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
include/linux/mmzone.h | 2 ++
kernel/memremap.c | 10 ++++------
mm/hmm.c | 2 --
3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index f0bbd85dc19a..6726fc175b51 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1134,6 +1134,8 @@ static inline unsigned long early_pfn_to_nid(unsigned long pfn)
* PFN_SECTION_SHIFT pfn to/from section number
*/
#define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
+#define PA_SECTION_SIZE (1UL << PA_SECTION_SHIFT)
+#define PA_SECTION_MASK (~(PA_SECTION_SIZE-1))
#define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)

#define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 4e59d29245f4..f355586ea54a 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -14,8 +14,6 @@
#include <linux/hmm.h>

static DEFINE_XARRAY(pgmap_array);
-#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
-#define SECTION_SIZE (1UL << PA_SECTION_SHIFT)

#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,
@@ -98,8 +96,8 @@ static void devm_memremap_pages_release(void *data)
put_page(pfn_to_page(pfn));

/* pages are dead and unused, undo the arch mapping */
- align_start = res->start & ~(SECTION_SIZE - 1);
- align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
+ align_start = res->start & ~(PA_SECTION_SIZE - 1);
+ align_size = ALIGN(res->start + resource_size(res), PA_SECTION_SIZE)
- align_start;

nid = page_to_nid(pfn_to_page(align_start >> PAGE_SHIFT));
@@ -160,8 +158,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
if (!pgmap->ref || !pgmap->kill)
return ERR_PTR(-EINVAL);

- align_start = res->start & ~(SECTION_SIZE - 1);
- align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
+ align_start = res->start & ~(PA_SECTION_SIZE - 1);
+ align_size = ALIGN(res->start + resource_size(res), PA_SECTION_SIZE)
- align_start;
align_end = align_start + align_size - 1;

diff --git a/mm/hmm.c b/mm/hmm.c
index 0db8491090b8..a7e7f8e33c5f 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -34,8 +34,6 @@
#include <linux/mmu_notifier.h>
#include <linux/memory_hotplug.h>

-#define PA_SECTION_SIZE (1UL << PA_SECTION_SHIFT)
-
#if IS_ENABLED(CONFIG_HMM_MIRROR)
static const struct mmu_notifier_ops hmm_mmu_notifier_ops;