mm: cleanup *pte_alloc* interfaces

There are few things about *pte_alloc*() helpers worth cleaning up:

 - 'vma' argument is unused, let's drop it;

 - most __pte_alloc() callers do speculative check for pmd_none(),
   before taking ptl: let's introduce pte_alloc() macro which does
   the check.

   The only direct user of __pte_alloc left is userfaultfd, which has
   different expectation about atomicity wrt pmd.

 - pte_alloc_map() and pte_alloc_map_lock() are redefined using
   pte_alloc().

[sudeep.holla@arm.com: fix build for arm64 hugetlbpage]
[sfr@canb.auug.org.au: fix arch/arm/mm/mmu.c some more]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

16 files changed, 27 insertions, 32 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 434d76f0b363..88fbe0d23ca6 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -732,7 +732,7 @@ static void *__init late_alloc(unsigned long sz)
         return ptr;
 }
 
-static pte_t * __init pte_alloc(pmd_t *pmd, unsigned long addr,
+static pte_t * __init arm_pte_alloc(pmd_t *pmd, unsigned long addr,
                                 unsigned long prot,
                                 void *(*alloc)(unsigned long sz))
 {
@@ -747,7 +747,7 @@ static pte_t * __init pte_alloc(pmd_t *pmd, unsigned long addr,
 static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
                                       unsigned long prot)
 {
-        return pte_alloc(pmd, addr, prot, early_alloc);
+        return arm_pte_alloc(pmd, addr, prot, early_alloc);
 }
 
 static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
@@ -756,7 +756,7 @@ static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
                                   void *(*alloc)(unsigned long sz),
                                   bool ng)
 {
-        pte_t *pte = pte_alloc(pmd, addr, type->prot_l1, alloc);
+        pte_t *pte = arm_pte_alloc(pmd, addr, type->prot_l1, alloc);
         do {
                 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)),
                             ng ? PTE_EXT_NG : 0);
diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c
index e683db1b90a3..b8d477321730 100644
--- a/arch/arm/mm/pgd.c
+++ b/arch/arm/mm/pgd.c
@@ -80,7 +80,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
                 if (!new_pmd)
                         goto no_pmd;
 
-                new_pte = pte_alloc_map(mm, NULL, new_pmd, 0);
+                new_pte = pte_alloc_map(mm, new_pmd, 0);
                 if (!new_pte)
                         goto no_pte;
 
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index da30529bb1f6..589fd28e1fb5 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -124,7 +124,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
                  * will be no pte_unmap() to correspond with this
                  * pte_alloc_map().
                  */
-                pte = pte_alloc_map(mm, NULL, pmd, addr);
+                pte = pte_alloc_map(mm, pmd, addr);
         } else if (sz == PMD_SIZE) {
                 if (IS_ENABLED(CONFIG_ARCH_WANT_HUGE_PMD_SHARE) &&
                     pud_none(*pud))
diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c
index f50d4b3f501a..85de86d36fdf 100644
--- a/arch/ia64/mm/hugetlbpage.c
+++ b/arch/ia64/mm/hugetlbpage.c
@@ -38,7 +38,7 @@ huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz)
         if (pud) {
                 pmd = pmd_alloc(mm, pud, taddr);
                 if (pmd)
-                        pte = pte_alloc_map(mm, NULL, pmd, taddr);
+                        pte = pte_alloc_map(mm, pmd, taddr);
         }
         return pte;
 }
diff --git a/arch/metag/mm/hugetlbpage.c b/arch/metag/mm/hugetlbpage.c
index 53f0f6c47027..b38700ae4e84 100644
--- a/arch/metag/mm/hugetlbpage.c
+++ b/arch/metag/mm/hugetlbpage.c
@@ -67,7 +67,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
         pgd = pgd_offset(mm, addr);
         pud = pud_offset(pgd, addr);
         pmd = pmd_offset(pud, addr);
-        pte = pte_alloc_map(mm, NULL, pmd, addr);
+        pte = pte_alloc_map(mm, pmd, addr);
         pgd->pgd &= ~_PAGE_SZ_MASK;
         pgd->pgd |= _PAGE_SZHUGE;
 
diff --git a/arch/parisc/mm/hugetlbpage.c b/arch/parisc/mm/hugetlbpage.c
index 54ba39262b82..5d6eea925cf4 100644
--- a/arch/parisc/mm/hugetlbpage.c
+++ b/arch/parisc/mm/hugetlbpage.c
@@ -63,7 +63,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
         if (pud) {
                 pmd = pmd_alloc(mm, pud, addr);
                 if (pmd)
-                        pte = pte_alloc_map(mm, NULL, pmd, addr);
+                        pte = pte_alloc_map(mm, pmd, addr);
         }
         return pte;
 }
diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c
index 6385f60209b6..cc948db74878 100644
--- a/arch/sh/mm/hugetlbpage.c
+++ b/arch/sh/mm/hugetlbpage.c
@@ -35,7 +35,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
                 if (pud) {
                         pmd = pmd_alloc(mm, pud, addr);
                         if (pmd)
-                                pte = pte_alloc_map(mm, NULL, pmd, addr);
+                                pte = pte_alloc_map(mm, pmd, addr);
                 }
         }
 
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index 131eaf4ad7f5..4977800e9770 100644
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -146,7 +146,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
         if (pud) {
                 pmd = pmd_alloc(mm, pud, addr);
                 if (pmd)
-                        pte = pte_alloc_map(mm, NULL, pmd, addr);
+                        pte = pte_alloc_map(mm, pmd, addr);
         }
         return pte;
 }
diff --git a/arch/tile/mm/hugetlbpage.c b/arch/tile/mm/hugetlbpage.c
index c034dc3fe2d4..e212c64682c5 100644
--- a/arch/tile/mm/hugetlbpage.c
+++ b/arch/tile/mm/hugetlbpage.c
@@ -77,7 +77,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
                 else {
                         if (sz != PAGE_SIZE << huge_shift[HUGE_SHIFT_PAGE])
                                 panic("Unexpected page size %#lx\n", sz);
-                        return pte_alloc_map(mm, NULL, pmd, addr);
+                        return pte_alloc_map(mm, pmd, addr);
                 }
         }
 #else
diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index 9591a66aa5c5..3943e9d7d13d 100644
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -31,7 +31,7 @@ static int init_stub_pte(struct mm_struct *mm, unsigned long proc,
         if (!pmd)
                 goto out_pmd;
 
-        pte = pte_alloc_map(mm, NULL, pmd, proc);
+        pte = pte_alloc_map(mm, pmd, proc);
         if (!pte)
                 goto out_pte;
 
diff --git a/arch/unicore32/mm/pgd.c b/arch/unicore32/mm/pgd.c
index 2ade20d8eab3..c572a28c76c9 100644
--- a/arch/unicore32/mm/pgd.c
+++ b/arch/unicore32/mm/pgd.c
@@ -54,7 +54,7 @@ pgd_t *get_pgd_slow(struct mm_struct *mm)
                 if (!new_pmd)
                         goto no_pmd;
 
-                new_pte = pte_alloc_map(mm, NULL, new_pmd, 0);
+                new_pte = pte_alloc_map(mm, new_pmd, 0);
                 if (!new_pte)
                         goto no_pte;
 
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 91a4496db434..e72a07f20b05 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -135,7 +135,7 @@ static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
         pmd = pmd_alloc(&tboot_mm, pud, vaddr);
         if (!pmd)
                 return -1;
-        pte = pte_alloc_map(&tboot_mm, NULL, pmd, vaddr);
+        pte = pte_alloc_map(&tboot_mm, pmd, vaddr);
         if (!pte)
                 return -1;
         set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
diff --git a/include/linux/mm.h b/include/linux/mm.h
index db9df3f78de1..75d1907b9009 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1545,8 +1545,7 @@ static inline void mm_dec_nr_pmds(struct mm_struct *mm)
 }
 #endif
 
-int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
-                pmd_t *pmd, unsigned long address);
+int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address);
 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);
 
 /*
@@ -1672,15 +1671,15 @@ static inline void pgtable_page_dtor(struct page *page)
         pte_unmap(pte);                                 \
 } while (0)
 
-#define pte_alloc_map(mm, vma, pmd, address)                            \
-        ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma,    \
-                                                        pmd, address))? \
-         NULL: pte_offset_map(pmd, address))
+#define pte_alloc(mm, pmd, address)                     \
+        (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd, address))
+
+#define pte_alloc_map(mm, pmd, address)                 \
+        (pte_alloc(mm, pmd, address) ? NULL : pte_offset_map(pmd, address))
 
 #define pte_alloc_map_lock(mm, pmd, address, ptlp)      \
-        ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL,   \
-                                                        pmd, address))? \
-                NULL: pte_offset_map_lock(mm, pmd, address, ptlp))
+        (pte_alloc(mm, pmd, address) ?                  \
+                 NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
 
 #define pte_alloc_kernel(pmd, address)                  \
         ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
diff --git a/mm/memory.c b/mm/memory.c
index 0e247642ed5b..1974fc02c4d0 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -562,8 +562,7 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
         }
 }
 
-int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
-                pmd_t *pmd, unsigned long address)
+int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
 {
         spinlock_t *ptl;
         pgtable_t new = pte_alloc_one(mm, address);
@@ -3419,12 +3418,11 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
         }
 
         /*
-         * Use __pte_alloc instead of pte_alloc_map, because we can't
+         * Use pte_alloc() instead of pte_alloc_map, because we can't
          * run pte_offset_map on the pmd, if an huge pmd could
          * materialize from under us from a different thread.
          */
-        if (unlikely(pmd_none(*pmd)) &&
-            unlikely(__pte_alloc(mm, vma, pmd, address)))
+        if (unlikely(pte_alloc(mm, pmd, address)))
                 return VM_FAULT_OOM;
         /*
          * If a huge pmd materialized under us just retry later.  Use
diff --git a/mm/mremap.c b/mm/mremap.c
index e30c8a6489a6..3fa0a467df66 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -213,8 +213,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
                                 continue;
                         VM_BUG_ON(pmd_trans_huge(*old_pmd));
                 }
-                if (pmd_none(*new_pmd) && __pte_alloc(new_vma->vm_mm, new_vma,
-                                                      new_pmd, new_addr))
+                if (pte_alloc(new_vma->vm_mm, new_pmd, new_addr))
                         break;
                 next = (new_addr + PMD_SIZE) & PMD_MASK;
                 if (extent > next - new_addr)
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 806b0c758c5b..9f3a0290b273 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -230,8 +230,7 @@ retry:
                         break;
                 }
                 if (unlikely(pmd_none(dst_pmdval)) &&
-                    unlikely(__pte_alloc(dst_mm, dst_vma, dst_pmd,
-                                         dst_addr))) {
+                    unlikely(__pte_alloc(dst_mm, dst_pmd, dst_addr))) {
                         err = -ENOMEM;
                         break;
                 }