mm: declare several functions

hulk inclusion
category: feature
bugzilla: 46904, https://gitee.com/openeuler/kernel/issues/I4QSHG
CVE: NA

--------------------------------

There are several functions that will be used in next patches for
dynamic hugetlb feature. Declare them.

No functional changes.
Signed-off-by: NLiu Shixin <liushixin2@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

include/linux/hugetlb.h

@@ -471,6 +471,9 @@ static inline struct hstate *hstate_inode(struct inode *i)
 {
 	return HUGETLBFS_SB(i->i_sb)->hstate;
 }
+
+bool prep_compound_gigantic_page(struct page *page, unsigned int order);
+
 #else /* !CONFIG_HUGETLBFS */
 
 #define is_file_hugepages(file)			false

include/linux/memcontrol.h

@@ -1239,6 +1239,22 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 						gfp_t gfp_mask,
 						unsigned long *total_scanned);
 
+/*
+ * Test whether @memcg has children, dead or alive.  Note that this
+ * function doesn't care whether @memcg has use_hierarchy enabled and
+ * returns %true if there are child csses according to the cgroup
+ * hierarchy.  Testing use_hierarchy is the caller's responsibility.
+ */
+static inline bool memcg_has_children(struct mem_cgroup *memcg)
+{
+	bool ret;
+
+	rcu_read_lock();
+	ret = css_next_child(NULL, &memcg->css);
+	rcu_read_unlock();
+	return ret;
+}
+
 #else /* CONFIG_MEMCG */
 
 #define MEM_CGROUP_ID_SHIFT	0

include/linux/memory_hotplug.h

@@ -284,6 +284,7 @@ static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
 
+extern int do_migrate_range(unsigned long start_pfn, unsigned long end_pfn);
 extern void try_offline_node(int nid);
 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
 extern int remove_memory(int nid, u64 start, u64 size);
@@ -291,6 +292,11 @@ extern void __remove_memory(int nid, u64 start, u64 size);
 extern int offline_and_remove_memory(int nid, u64 start, u64 size);
 
 #else
+static inline int do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
+{
+	return -ENOSYS;
+}
+
 static inline void try_offline_node(int nid) {}
 
 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)

mm/hugetlb.c

@@ -1633,7 +1633,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
 	spin_unlock_irq(&hugetlb_lock);
 }
 
-static bool prep_compound_gigantic_page(struct page *page, unsigned int order)
+bool prep_compound_gigantic_page(struct page *page, unsigned int order)
 {
 	int i, j;
 	int nr_pages = 1 << order;

mm/internal.h

@@ -197,6 +197,9 @@ extern void __free_pages_core(struct page *page, unsigned int order);
 extern void prep_compound_page(struct page *page, unsigned int order);
 extern void post_alloc_hook(struct page *page, unsigned int order,
 					gfp_t gfp_flags);
+extern void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
+							unsigned int alloc_flags);
+extern bool free_pages_prepare(struct page *page, unsigned int order, bool check_free);
 extern int user_min_free_kbytes;
 
 extern void zone_pcp_update(struct zone *zone);

mm/memcontrol.c

@@ -3402,22 +3402,6 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 	return nr_reclaimed;
 }
 
-/*
- * Test whether @memcg has children, dead or alive.  Note that this
- * function doesn't care whether @memcg has use_hierarchy enabled and
- * returns %true if there are child csses according to the cgroup
- * hierarchy.  Testing use_hierarchy is the caller's responsibility.
- */
-static inline bool memcg_has_children(struct mem_cgroup *memcg)
-{
-	bool ret;
-
-	rcu_read_lock();
-	ret = css_next_child(NULL, &memcg->css);
-	rcu_read_unlock();
-	return ret;
-}
-
 /*
  * Reclaims as many pages from the given memcg as possible.
  *

mm/memory_hotplug.c

@@ -1165,8 +1165,7 @@ static int scan_movable_pages(unsigned long start, unsigned long end,
 	return 0;
 }
 
-static int
-do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
+int do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 {
 	unsigned long pfn;
 	struct page *page, *head;

mm/page_alloc.c

@@ -1203,7 +1203,7 @@ static void kernel_init_free_pages(struct page *page, int numpages)
 	kasan_enable_current();
 }
 
-static __always_inline bool free_pages_prepare(struct page *page,
+__always_inline bool free_pages_prepare(struct page *page,
 					unsigned int order, bool check_free)
 {
 	int bad = 0;
@@ -2283,8 +2283,8 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
 	set_page_owner(page, order, gfp_flags);
 }
 
-static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
-							unsigned int alloc_flags)
+void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
+						unsigned int alloc_flags)
 {
 	post_alloc_hook(page, order, gfp_flags);