Code to deal with reserved/managed pages are duplicated by many
architectures, so introduce common help functions to reduce duplicated
code. These common help functions will also be used to concentrate code
to modify totalram_pages and zone->managed_pages, which makes the code
much more clear.
Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx>
---
include/linux/mm.h | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
mm/page_alloc.c | 20 ++++++++++++++++++++
2 files changed, 68 insertions(+)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7acc9dc..d75c14b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1295,6 +1295,54 @@ extern void free_area_init_node(int nid, unsigned long * zones_size,
unsigned long zone_start_pfn, unsigned long *zholes_size);
extern void free_initmem(void);
+/*
+ * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
+ * into the buddy system. The freed pages will be poisoned with pattern
+ * "poison" if it's non-zero.
+ * Return pages freed into the buddy system.
+ */
+extern unsigned long free_reserved_area(unsigned long start, unsigned long end,
+ int poison, char *s);
+
+static inline void adjust_managed_page_count(struct page *page, long count)
+{
+ totalram_pages += count;
+}
+
+/* Free the reserved page into the buddy system, so it gets managed. */
+static inline void __free_reserved_page(struct page *page)
+{
+ ClearPageReserved(page);
+ init_page_count(page);
+ __free_page(page);
+}
+
+static inline void free_reserved_page(struct page *page)
+{
+ __free_reserved_page(page);
+ adjust_managed_page_count(page, 1);
+}
+
+static inline void mark_page_reserved(struct page *page)
+{
+ SetPageReserved(page);
+ adjust_managed_page_count(page, -1);
+}
+
+/*
+ * Default method to free all the __init memory into the buddy system.
+ * The freed pages will be poisoned with pattern "poison" if it is
+ * non-zero. Return pages freed into the buddy system.
+ */
+static inline unsigned long free_initmem_default(int poison)
+{
+ extern char __init_begin[], __init_end[];
+
+ return free_reserved_area(PAGE_ALIGN((unsigned long)&__init_begin) ,
+ ((unsigned long)&__init_end) & PAGE_MASK,
+ poison, "unused kernel");
+}
+
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/*
* With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8fcced7..0fadb09 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5113,6 +5113,26 @@ early_param("movablecore", cmdline_parse_movablecore);
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
+unsigned long free_reserved_area(unsigned long start, unsigned long end,
+ int poison, char *s)
+{
+ unsigned long pages, pos;
+
+ pos = start = PAGE_ALIGN(start);
+ end &= PAGE_MASK;
+ for (pages = 0; pos < end; pos += PAGE_SIZE, pages++) {
+ if (poison)
+ memset((void *)pos, poison, PAGE_SIZE);
+ free_reserved_page(virt_to_page(pos));
+ }
+
+ if (pages && s)
+ pr_info("Freeing %s memory: %ldK (%lx - %lx)\n",
+ s, pages << (PAGE_SHIFT - 10), start, end);
+
+ return pages;
+}
+
/**
* set_dma_reserve - set the specified number of pages reserved in the first zone
* @new_dma_reserve: The number of pages to mark reserved
--
1.7.9.5
--
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