sparc64/mm: Implement pXX_leaf_size() support

Sparc64 has non-pagetable aligned large page support; wire up the
pXX_leaf_size() functions to report the correct pagetable page size.

This enables PERF_SAMPLE_{DATA,CODE}_PAGE_SIZE to report accurate
pagetable leaf sizes.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201126121121.301768209@infradead.org

arch/sparc/include/asm/pgtable_64.h

@@ -1121,6 +1121,19 @@ extern unsigned long cmdline_memory_size;
 
 asmlinkage void do_sparc64_fault(struct pt_regs *regs);
 
+#ifdef CONFIG_HUGETLB_PAGE
+
+#define pud_leaf_size pud_leaf_size
+extern unsigned long pud_leaf_size(pud_t pud);
+
+#define pmd_leaf_size pmd_leaf_size
+extern unsigned long pmd_leaf_size(pmd_t pmd);
+
+#define pte_leaf_size pte_leaf_size
+extern unsigned long pte_leaf_size(pte_t pte);
+
+#endif /* CONFIG_HUGETLB_PAGE */
+
 #endif /* !(__ASSEMBLY__) */
 
 #endif /* !(_SPARC64_PGTABLE_H) */

arch/sparc/mm/hugetlbpage.c

@@ -247,14 +247,17 @@ static unsigned int sun4u_huge_tte_to_shift(pte_t entry)
 	return shift;
 }
 
-static unsigned int huge_tte_to_shift(pte_t entry)
+static unsigned long tte_to_shift(pte_t entry)
 {
-	unsigned long shift;
-
 	if (tlb_type == hypervisor)
-		shift = sun4v_huge_tte_to_shift(entry);
-	else
-		shift = sun4u_huge_tte_to_shift(entry);
+		return sun4v_huge_tte_to_shift(entry);
+
+	return sun4u_huge_tte_to_shift(entry);
+}
+
+static unsigned int huge_tte_to_shift(pte_t entry)
+{
+	unsigned long shift = tte_to_shift(entry);
 
 	if (shift == PAGE_SHIFT)
 		WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n",
@@ -272,6 +275,10 @@ static unsigned long huge_tte_to_size(pte_t pte)
 	return size;
 }
 
+unsigned long pud_leaf_size(pud_t pud) { return 1UL << tte_to_shift(*(pte_t *)&pud); }
+unsigned long pmd_leaf_size(pmd_t pmd) { return 1UL << tte_to_shift(*(pte_t *)&pmd); }
+unsigned long pte_leaf_size(pte_t pte) { return 1UL << tte_to_shift(pte); }
+
 pte_t *huge_pte_alloc(struct mm_struct *mm,
 			unsigned long addr, unsigned long sz)
 {