mm/memory-failure: move some function declarations into internal.h

There are some functions only used inside mm.  Move them into internal.h. 
No functional change intended.

Link: https://lkml.kernel.org/r/20240612071835.157004-11-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202405251049.hxjwX7zO-lkp@intel.com/
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/mm.h

@@ -4000,7 +4000,6 @@ extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
 					bool *migratable_cleared);
 void num_poisoned_pages_inc(unsigned long pfn);
 void num_poisoned_pages_sub(unsigned long pfn, long i);
-struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);
 #else
 static inline void memory_failure_queue(unsigned long pfn, int flags)
 {
@@ -4021,12 +4020,6 @@ static inline void num_poisoned_pages_sub(unsigned long pfn, long i)
 }
 #endif
 
-#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM)
-void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
-		     struct vm_area_struct *vma, struct list_head *to_kill,
-		     unsigned long ksm_addr);
-#endif
-
 #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
 extern void memblk_nr_poison_inc(unsigned long pfn);
 extern void memblk_nr_poison_sub(unsigned long pfn, long i);

include/linux/page-flags.h

@@ -616,11 +616,6 @@ PAGEFLAG_FALSE(Uncached, uncached)
 PAGEFLAG(HWPoison, hwpoison, PF_ANY)
 TESTSCFLAG(HWPoison, hwpoison, PF_ANY)
 #define __PG_HWPOISON (1UL << PG_hwpoison)
-#define MAGIC_HWPOISON	0x48575053U	/* HWPS */
-extern void SetPageHWPoisonTakenOff(struct page *page);
-extern void ClearPageHWPoisonTakenOff(struct page *page);
-extern bool take_page_off_buddy(struct page *page);
-extern bool put_page_back_buddy(struct page *page);
 #else
 PAGEFLAG_FALSE(HWPoison, hwpoison)
 #define __PG_HWPOISON 0

include/linux/rmap.h

@@ -747,8 +747,6 @@ int pfn_mkclean_range(unsigned long pfn, unsigned long nr_pages, pgoff_t pgoff,
 
 void remove_migration_ptes(struct folio *src, struct folio *dst, bool locked);
 
-unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
-
 /*
  * rmap_walk_control: To control rmap traversing for specific needs
  *

mm/internal.h

@@ -1062,6 +1062,16 @@ extern u64 hwpoison_filter_flags_mask;
 extern u64 hwpoison_filter_flags_value;
 extern u64 hwpoison_filter_memcg;
 extern u32 hwpoison_filter_enable;
+#define MAGIC_HWPOISON	0x48575053U	/* HWPS */
+void SetPageHWPoisonTakenOff(struct page *page);
+void ClearPageHWPoisonTakenOff(struct page *page);
+bool take_page_off_buddy(struct page *page);
+bool put_page_back_buddy(struct page *page);
+struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);
+void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
+		     struct vm_area_struct *vma, struct list_head *to_kill,
+		     unsigned long ksm_addr);
+unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
 
 extern unsigned long  __must_check vm_mmap_pgoff(struct file *, unsigned long,
         unsigned long, unsigned long,