hugetlb: convert PageHugeTemporary() to HPageTemporary flag

Use new hugetlb specific HPageTemporary flag to replace the
PageHugeTemporary() interfaces.  PageHugeTemporary does contain a
PageHuge() check.  However, this interface is only used within hugetlb
code where we know we are dealing with a hugetlb page.  Therefore, the
check can be eliminated.

Link: https://lkml.kernel.org/r/20210122195231.324857-5-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/hugetlb.h

@@ -483,10 +483,15 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
  * HPG_migratable  - Set after a newly allocated page is added to the page
  *	cache and/or page tables.  Indicates the page is a candidate for
  *	migration.
+ * HPG_temporary - - Set on a page that is temporarily allocated from the buddy
+ *	allocator.  Typically used for migration target pages when no pages
+ *	are available in the pool.  The hugetlb free page path will
+ *	immediately free pages with this flag set to the buddy allocator.
  */
 enum hugetlb_page_flags {
 	HPG_restore_reserve = 0,
 	HPG_migratable,
+	HPG_temporary,
 	__NR_HPAGEFLAGS,
 };
 
@@ -530,6 +535,7 @@ static inline void ClearHPage##uname(struct page *page)		\
  */
 HPAGEFLAG(RestoreReserve, restore_reserve)
 HPAGEFLAG(Migratable, migratable)
+HPAGEFLAG(Temporary, temporary)
 
 #ifdef CONFIG_HUGETLB_PAGE