sparc, thp: remove infrastructure for handling splitting PMDs

With new refcounting we don't need to mark PMDs splitting.  Let's drop
code to handle this.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/sparc/include/asm/pgtable_64.h

@@ -681,13 +681,6 @@ static inline unsigned long pmd_trans_huge(pmd_t pmd)
 	return pte_val(pte) & _PAGE_PMD_HUGE;
 }
 
-static inline unsigned long pmd_trans_splitting(pmd_t pmd)
-{
-	pte_t pte = __pte(pmd_val(pmd));
-
-	return pmd_trans_huge(pmd) && pte_special(pte);
-}
-
 #define has_transparent_hugepage() 1
 
 static inline pmd_t pmd_mkold(pmd_t pmd)
@@ -735,15 +728,6 @@ static inline pmd_t pmd_mkwrite(pmd_t pmd)
 	return __pmd(pte_val(pte));
 }
 
-static inline pmd_t pmd_mksplitting(pmd_t pmd)
-{
-	pte_t pte = __pte(pmd_val(pmd));
-
-	pte = pte_mkspecial(pte);
-
-	return __pmd(pte_val(pte));
-}
-
 static inline pgprot_t pmd_pgprot(pmd_t entry)
 {
 	unsigned long val = pmd_val(entry);

arch/sparc/mm/fault_64.c

@@ -113,9 +113,6 @@ static unsigned int get_user_insn(unsigned long tpc)
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 	if (pmd_trans_huge(*pmdp)) {
-		if (pmd_trans_splitting(*pmdp))
-			goto out_irq_enable;
-
 		pa  = pmd_pfn(*pmdp) << PAGE_SHIFT;
 		pa += tpc & ~HPAGE_MASK;
 

arch/sparc/mm/gup.c

@@ -114,7 +114,7 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
 		pmd_t pmd = *pmdp;
 
 		next = pmd_addr_end(addr, end);
-		if (pmd_none(pmd) || pmd_trans_splitting(pmd))
+		if (pmd_none(pmd))
 			return 0;
 		if (unlikely(pmd_large(pmd))) {
 			if (!gup_huge_pmd(pmdp, pmd, addr, next,