[PATCH] hugetlb: Remove PageHeadHuge()

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

Sidhartha Kumar removed the last caller of PageHeadHuge(), so we can
now remove it and make folio_test_hugetlb() the real implementation.
Add kernel-doc for folio_test_hugetlb().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 include/linux/page-flags.h |  7 +------
 mm/hugetlb.c               | 18 +++++++++++-------
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 6b3e138613e1..88600a94fa91 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -811,14 +811,9 @@ static inline void ClearPageCompound(struct page *page)
 
 #ifdef CONFIG_HUGETLB_PAGE
 int PageHuge(struct page *page);
-int PageHeadHuge(struct page *page);
-static inline bool folio_test_hugetlb(struct folio *folio)
-{
-	return PageHeadHuge(&folio->page);
-}
+bool folio_test_hugetlb(struct folio *folio);
 #else
 TESTPAGEFLAG_FALSE(Huge, hugetlb)
-TESTPAGEFLAG_FALSE(HeadHuge, headhuge)
 #endif
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4dd722c35a7f..ff686074c481 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2050,19 +2050,23 @@ int PageHuge(struct page *page)
 }
 EXPORT_SYMBOL_GPL(PageHuge);
 
-/*
- * PageHeadHuge() only returns true for hugetlbfs head page, but not for
- * normal or transparent huge pages.
+/**
+ * folio_test_hugetlb - Determine if the folio belongs to hugetlbfs
+ * @folio: The folio to test.
+ *
+ * Context: Any context.  Caller should have a reference on the folio to
+ * prevent it from being turned into a tail page.
+ * Return: True for hugetlbfs folios, false for anon folios or folios
+ * belonging to other filesystems.
  */
-int PageHeadHuge(struct page *page_head)
+bool folio_test_hugetlb(struct folio *folio)
 {
-	struct folio *folio = (struct folio *)page_head;
 	if (!folio_test_large(folio))
-		return 0;
+		return false;
 
 	return folio->_folio_dtor == HUGETLB_PAGE_DTOR;
 }
-EXPORT_SYMBOL_GPL(PageHeadHuge);
+EXPORT_SYMBOL_GPL(folio_test_hugetlb);
 
 /*
  * Find and lock address space (mapping) in write mode.
-- 
2.39.2