+ mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch added to -mm tree

+ mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm: constify get_pfnblock_flags_mask and get_pfnblock_migratetype
has been added to the -mm tree.  Its filename is
     mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm: constify get_pfnblock_flags_mask and get_pfnblock_migratetype

The struct page is not modified by these routines, so it can be marked
const.

Link: https://lkml.kernel.org/r/20210416231531.2521383-6-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/pageblock-flags.h |    2 +-
 mm/page_alloc.c                 |   13 +++++++------
 2 files changed, 8 insertions(+), 7 deletions(-)

--- a/include/linux/pageblock-flags.h~mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype
+++ a/include/linux/pageblock-flags.h
@@ -54,7 +54,7 @@ extern unsigned int pageblock_order;
 /* Forward declaration */
 struct page;
 
-unsigned long get_pfnblock_flags_mask(struct page *page,
+unsigned long get_pfnblock_flags_mask(const struct page *page,
 				unsigned long pfn,
 				unsigned long mask);
 
--- a/mm/page_alloc.c~mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype
+++ a/mm/page_alloc.c
@@ -474,7 +474,7 @@ static inline bool defer_init(int nid, u
 #endif
 
 /* Return a pointer to the bitmap storing bits affecting a block of pages */
-static inline unsigned long *get_pageblock_bitmap(struct page *page,
+static inline unsigned long *get_pageblock_bitmap(const struct page *page,
 							unsigned long pfn)
 {
 #ifdef CONFIG_SPARSEMEM
@@ -484,7 +484,7 @@ static inline unsigned long *get_pageblo
 #endif /* CONFIG_SPARSEMEM */
 }
 
-static inline int pfn_to_bitidx(struct page *page, unsigned long pfn)
+static inline int pfn_to_bitidx(const struct page *page, unsigned long pfn)
 {
 #ifdef CONFIG_SPARSEMEM
 	pfn &= (PAGES_PER_SECTION-1);
@@ -495,7 +495,7 @@ static inline int pfn_to_bitidx(struct p
 }
 
 static __always_inline
-unsigned long __get_pfnblock_flags_mask(struct page *page,
+unsigned long __get_pfnblock_flags_mask(const struct page *page,
 					unsigned long pfn,
 					unsigned long mask)
 {
@@ -520,13 +520,14 @@ unsigned long __get_pfnblock_flags_mask(
  *
  * Return: pageblock_bits flags
  */
-unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn,
-					unsigned long mask)
+unsigned long get_pfnblock_flags_mask(const struct page *page,
+					unsigned long pfn, unsigned long mask)
 {
 	return __get_pfnblock_flags_mask(page, pfn, mask);
 }
 
-static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
+static __always_inline int get_pfnblock_migratetype(const struct page *page,
+					unsigned long pfn)
 {
 	return __get_pfnblock_flags_mask(page, pfn, MIGRATETYPE_MASK);
 }
_

Patches currently in -mm which might be from willy@infradead.org are

mm-make-__dump_page-static.patch
mm-debug-factor-pagepoisoned-out-of-__dump_page.patch
mm-page_owner-constify-dump_page_owner.patch
mm-make-compound_head-const-preserving.patch
mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch
mm-constify-page_count-and-page_ref_count.patch