mm: Create ptdesc equivalents for pgtable_{pte,pmd}_page_{ctor,dtor}

Creates ptdesc_pte_ctor(), ptdesc_pmd_ctor(), ptdesc_pte_dtor(), and
ptdesc_pmd_dtor() and make the original pgtable constructor/destructors
wrappers.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

include/linux/mm.h

@@ -2821,20 +2821,34 @@ static inline bool ptlock_init(struct ptdesc *ptdesc) { return true; }
 static inline void ptlock_free(struct ptdesc *ptdesc) {}
 #endif /* USE_SPLIT_PTE_PTLOCKS */
 
-static inline bool pgtable_pte_page_ctor(struct page *page)
+static inline bool ptdesc_pte_ctor(struct ptdesc *ptdesc)
 {
-	if (!ptlock_init(page_ptdesc(page)))
+	struct folio *folio = ptdesc_folio(ptdesc);
+
+	if (!ptlock_init(ptdesc))
 		return false;
-	__SetPageTable(page);
-	inc_lruvec_page_state(page, NR_PAGETABLE);
+	__SetPageTable(&folio->page);
+	lruvec_stat_add_folio(folio, NR_PAGETABLE);
 	return true;
 }
 
+static inline bool pgtable_pte_page_ctor(struct page *page)
+{
+	return ptdesc_pte_ctor(page_ptdesc(page));
+}
+
+static inline void ptdesc_pte_dtor(struct ptdesc *ptdesc)
+{
+	struct folio *folio = ptdesc_folio(ptdesc);
+
+	ptlock_free(ptdesc);
+	__ClearPageTable(&folio->page);
+	lruvec_stat_sub_folio(folio, NR_PAGETABLE);
+}
+
 static inline void pgtable_pte_page_dtor(struct page *page)
 {
-	ptlock_free(page_ptdesc(page));
-	__ClearPageTable(page);
-	dec_lruvec_page_state(page, NR_PAGETABLE);
+	ptdesc_pte_dtor(page_ptdesc(page));
 }
 
 #define pte_offset_map_lock(mm, pmd, address, ptlp)	\
@@ -2916,20 +2930,34 @@ static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
 	return ptl;
 }
 
-static inline bool pgtable_pmd_page_ctor(struct page *page)
+static inline bool ptdesc_pmd_ctor(struct ptdesc *ptdesc)
 {
-	if (!pmd_ptlock_init(page_ptdesc(page)))
+	struct folio *folio = ptdesc_folio(ptdesc);
+
+	if (!pmd_ptlock_init(ptdesc))
 		return false;
-	__SetPageTable(page);
-	inc_lruvec_page_state(page, NR_PAGETABLE);
+	__SetPageTable(&folio->page);
+	lruvec_stat_add_folio(folio, NR_PAGETABLE);
 	return true;
 }
 
+static inline bool pgtable_pmd_page_ctor(struct page *page)
+{
+	return ptdesc_pmd_ctor(page_ptdesc(page));
+}
+
+static inline void ptdesc_pmd_dtor(struct ptdesc *ptdesc)
+{
+	struct folio *folio = ptdesc_folio(ptdesc);
+
+	pmd_ptlock_free(ptdesc);
+	__ClearPageTable(&folio->page);
+	lruvec_stat_sub_folio(folio, NR_PAGETABLE);
+}
+
 static inline void pgtable_pmd_page_dtor(struct page *page)
 {
-	pmd_ptlock_free(page_ptdesc(page));
-	__ClearPageTable(page);
-	dec_lruvec_page_state(page, NR_PAGETABLE);
+	ptdesc_pmd_dtor(page_ptdesc(page));
 }
 
 /*