thp: add pmd mangling generic functions

Some are needed to build but not actually used on archs not supporting
transparent hugepages.  Others like pmdp_clear_flush are used by x86 too.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 0ab2cd2..f1eddf7 100644 (file)
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -5,67 +5,108 @@
 #ifdef CONFIG_MMU
 
 #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
-/*
- * Largely same as above, but only sets the access flags (dirty,
- * accessed, and writable). Furthermore, we know it always gets set
- * to a "more permissive" setting, which allows most architectures
- * to optimize this. We return whether the PTE actually changed, which
- * in turn instructs the caller to do things like update__mmu_cache.
- * This used to be done in the caller, but sparc needs minor faults to
- * force that call on sun4c so we changed this macro slightly
- */
-#define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
-({                                                                       \
-       int __changed = !pte_same(*(__ptep), __entry);                    \
-       if (__changed) {                                                  \
-               set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry); \
-               flush_tlb_page(__vma, __address);                         \
-       }                                                                 \
-       __changed;                                                        \
-})
+extern int ptep_set_access_flags(struct vm_area_struct *vma,
+                                unsigned long address, pte_t *ptep,
+                                pte_t entry, int dirty);
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
+extern int pmdp_set_access_flags(struct vm_area_struct *vma,
+                                unsigned long address, pmd_t *pmdp,
+                                pmd_t entry, int dirty);
 #endif
 
 #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
-#define ptep_test_and_clear_young(__vma, __address, __ptep)            \
-({                                                                     \
-       pte_t __pte = *(__ptep);                                        \
-       int r = 1;                                                      \
-       if (!pte_young(__pte))                                          \
-               r = 0;                                                  \
-       else                                                            \
-               set_pte_at((__vma)->vm_mm, (__address),                 \
-                          (__ptep), pte_mkold(__pte));                 \
-       r;                                                              \
-})
+static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
+                                           unsigned long address,
+                                           pte_t *ptep)
+{
+       pte_t pte = *ptep;
+       int r = 1;
+       if (!pte_young(pte))
+               r = 0;
+       else
+               set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte));
+       return r;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
+                                           unsigned long address,
+                                           pmd_t *pmdp)
+{
+       pmd_t pmd = *pmdp;
+       int r = 1;
+       if (!pmd_young(pmd))
+               r = 0;
+       else
+               set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));
+       return r;
+}
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
+                                           unsigned long address,
+                                           pmd_t *pmdp)
+{
+       BUG();
+       return 0;
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 #endif
 
 #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
-#define ptep_clear_flush_young(__vma, __address, __ptep)               \
-({                                                                     \
-       int __young;                                                    \
-       __young = ptep_test_and_clear_young(__vma, __address, __ptep);  \
-       if (__young)                                                    \
-               flush_tlb_page(__vma, __address);                       \
-       __young;                                                        \
-})
+int ptep_clear_flush_young(struct vm_area_struct *vma,
+                          unsigned long address, pte_t *ptep);
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
+int pmdp_clear_flush_young(struct vm_area_struct *vma,
+                          unsigned long address, pmd_t *pmdp);
 #endif
 
 #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
-#define ptep_get_and_clear(__mm, __address, __ptep)                    \
-({                                                                     \
-       pte_t __pte = *(__ptep);                                        \
-       pte_clear((__mm), (__address), (__ptep));                       \
-       __pte;                                                          \
+static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
+                                      unsigned long address,
+                                      pte_t *ptep)
+{
+       pte_t pte = *ptep;
+       pte_clear(mm, address, ptep);
+       return pte;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
+                                      unsigned long address,
+                                      pmd_t *pmdp)
+{
+       pmd_t pmd = *pmdp;
+       pmd_clear(mm, address, pmdp);
+       return pmd;
 })
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
+                                      unsigned long address,
+                                      pmd_t *pmdp)
+{
+       BUG();
+       return __pmd(0);
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 #endif
 
 #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
-#define ptep_get_and_clear_full(__mm, __address, __ptep, __full)       \
-({                                                                     \
-       pte_t __pte;                                                    \
-       __pte = ptep_get_and_clear((__mm), (__address), (__ptep));      \
-       __pte;                                                          \
-})
+static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
+                                           unsigned long address, pte_t *ptep,
+                                           int full)
+{
+       pte_t pte;
+       pte = ptep_get_and_clear(mm, address, ptep);
+       return pte;
+}
 #endif
 
 /*
@@ -74,20 +115,25 @@
  * not present, or in the process of an address space destruction.
  */
 #ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL
-#define pte_clear_not_present_full(__mm, __address, __ptep, __full)    \
-do {                                                                   \
-       pte_clear((__mm), (__address), (__ptep));                       \
-} while (0)
+static inline void pte_clear_not_present_full(struct mm_struct *mm,
+                                             unsigned long address,
+                                             pte_t *ptep,
+                                             int full)
+{
+       pte_clear(mm, address, ptep);
+}
 #endif
 
 #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
-#define ptep_clear_flush(__vma, __address, __ptep)                     \
-({                                                                     \
-       pte_t __pte;                                                    \
-       __pte = ptep_get_and_clear((__vma)->vm_mm, __address, __ptep);  \
-       flush_tlb_page(__vma, __address);                               \
-       __pte;                                                          \
-})
+extern pte_t ptep_clear_flush(struct vm_area_struct *vma,
+                             unsigned long address,
+                             pte_t *ptep);
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
+extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
+                             unsigned long address,
+                             pmd_t *pmdp);
 #endif
 
 #ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
@@ -99,8 +145,49 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres
 }
 #endif
 
+#ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline void pmdp_set_wrprotect(struct mm_struct *mm,
+                                     unsigned long address, pmd_t *pmdp)
+{
+       pmd_t old_pmd = *pmdp;
+       set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd));
+}
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+static inline void pmdp_set_wrprotect(struct mm_struct *mm,
+                                     unsigned long address, pmd_t *pmdp)
+{
+       BUG();
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
+extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
+                             unsigned long address,
+                             pmd_t *pmdp);
+#endif
+
 #ifndef __HAVE_ARCH_PTE_SAME
-#define pte_same(A,B)  (pte_val(A) == pte_val(B))
+static inline int pte_same(pte_t pte_a, pte_t pte_b)
+{
+       return pte_val(pte_a) == pte_val(pte_b);
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMD_SAME
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
+{
+       return pmd_val(pmd_a) == pmd_val(pmd_b);
+}
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
+{
+       BUG();
+       return 0;
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 #endif
 
 #ifndef __HAVE_ARCH_PAGE_TEST_DIRTY
@@ -357,6 +444,13 @@ static inline int pmd_trans_splitting(pmd_t pmd)
 {
        return 0;
 }
+#ifndef __HAVE_ARCH_PMD_WRITE
+static inline int pmd_write(pmd_t pmd)
+{
+       BUG();
+       return 0;
+}
+#endif /* __HAVE_ARCH_PMD_WRITE */
 #endif
 
 #endif /* !__ASSEMBLY__ */

diff --git a/mm/Makefile b/mm/Makefile
index f73f75a..380772a 100644 (file)
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -5,7 +5,7 @@
 mmu-y                  := nommu.o
 mmu-$(CONFIG_MMU)      := fremap.o highmem.o madvise.o memory.o mincore.o \
                           mlock.o mmap.o mprotect.o mremap.o msync.o rmap.o \
-                          vmalloc.o pagewalk.o
+                          vmalloc.o pagewalk.o pgtable-generic.o
 
 obj-y                  := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
                           maccess.o page_alloc.o page-writeback.o \

diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
new file mode 100644 (file)
index 0000000..d030548
--- /dev/null
+++ b/mm/pgtable-generic.c
@@ -0,0 +1,123 @@
+/*
+ *  mm/pgtable-generic.c
+ *
+ *  Generic pgtable methods declared in asm-generic/pgtable.h
+ *
+ *  Copyright (C) 2010  Linus Torvalds
+ */
+
+#include <asm/tlb.h>
+#include <asm-generic/pgtable.h>
+
+#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
+/*
+ * Only sets the access flags (dirty, accessed, and
+ * writable). Furthermore, we know it always gets set to a "more
+ * permissive" setting, which allows most architectures to optimize
+ * this. We return whether the PTE actually changed, which in turn
+ * instructs the caller to do things like update__mmu_cache.  This
+ * used to be done in the caller, but sparc needs minor faults to
+ * force that call on sun4c so we changed this macro slightly
+ */
+int ptep_set_access_flags(struct vm_area_struct *vma,
+                         unsigned long address, pte_t *ptep,
+                         pte_t entry, int dirty)
+{
+       int changed = !pte_same(*ptep, entry);
+       if (changed) {
+               set_pte_at(vma->vm_mm, address, ptep, entry);
+               flush_tlb_page(vma, address);
+       }
+       return changed;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
+int pmdp_set_access_flags(struct vm_area_struct *vma,
+                         unsigned long address, pmd_t *pmdp,
+                         pmd_t entry, int dirty)
+{
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+       int changed = !pmd_same(*pmdp, entry);
+       VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+       if (changed) {
+               set_pmd_at(vma->vm_mm, address, pmdp, entry);
+               flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+       }
+       return changed;
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+       BUG();
+       return 0;
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+}
+#endif
+
+#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+int ptep_clear_flush_young(struct vm_area_struct *vma,
+                          unsigned long address, pte_t *ptep)
+{
+       int young;
+       young = ptep_test_and_clear_young(vma, address, ptep);
+       if (young)
+               flush_tlb_page(vma, address);
+       return young;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
+int pmdp_clear_flush_young(struct vm_area_struct *vma,
+                          unsigned long address, pmd_t *pmdp)
+{
+       int young;
+#ifndef CONFIG_TRANSPARENT_HUGEPAGE
+       BUG();
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+       VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+       young = pmdp_test_and_clear_young(vma, address, pmdp);
+       if (young)
+               flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+       return young;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
+pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
+                      pte_t *ptep)
+{
+       pte_t pte;
+       pte = ptep_get_and_clear((vma)->vm_mm, address, ptep);
+       flush_tlb_page(vma, address);
+       return pte;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
+pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
+                      pmd_t *pmdp)
+{
+       pmd_t pmd;
+#ifndef CONFIG_TRANSPARENT_HUGEPAGE
+       BUG();
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+       VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+       pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
+       flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+       return pmd;
+}
+#endif
+
+#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
+pmd_t pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+                          pmd_t *pmdp)
+{
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+       pmd_t pmd = pmd_mksplitting(*pmdp);
+       VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+       set_pmd_at(vma->vm_mm, address, pmdp, pmd);
+       /* tlb flush only to serialize against gup-fast */
+       flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+       BUG();
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+}
+#endif