From 10ed63415223b16d7e80ba528556500231814232 Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Date: Fri, 17 Aug 2018 15:45:15 -0700
Subject: [PATCH] mm/page_ext.c: constify lookup_page_ext() argument
lookup_page_ext() finds 'struct page_ext' for a given page. It requires
only read access to the given struct page.
Current implemnentation takes 'struct page *' as an argument. It makes
compiler complain when 'const struct page *' passed.
Change the argument to 'const struct page *'.
Link: http://lkml.kernel.org/r/20180531135457.20167-3-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/page_ext.h | 4 ++--
mm/page_ext.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h
index bbec618a614b..f84f167ec04c 100644
--- a/include/linux/page_ext.h
+++ b/include/linux/page_ext.h
@@ -50,7 +50,7 @@ static inline void page_ext_init(void)
}
#endif
-struct page_ext *lookup_page_ext(struct page *page);
+struct page_ext *lookup_page_ext(const struct page *page);
#else /* !CONFIG_PAGE_EXTENSION */
struct page_ext;
@@ -59,7 +59,7 @@ static inline void pgdat_page_ext_init(struct pglist_data *pgdat)
{
}
-static inline struct page_ext *lookup_page_ext(struct page *page)
+static inline struct page_ext *lookup_page_ext(const struct page *page)
{
return NULL;
}
diff --git a/mm/page_ext.c b/mm/page_ext.c
index 5295ef331165..a9826da84ccb 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -120,7 +120,7 @@ void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
pgdat->node_page_ext = NULL;
}
-struct page_ext *lookup_page_ext(struct page *page)
+struct page_ext *lookup_page_ext(const struct page *page)
{
unsigned long pfn = page_to_pfn(page);
unsigned long index;
@@ -195,7 +195,7 @@ fail:
#else /* CONFIG_FLAT_NODE_MEM_MAP */
-struct page_ext *lookup_page_ext(struct page *page)
+struct page_ext *lookup_page_ext(const struct page *page)
{
unsigned long pfn = page_to_pfn(page);
struct mem_section *section = __pfn_to_section(pfn);