mm/hugetlb: use pmd_page() in follow_huge_pmd()

[ Upstream commit 97534127012f0e396eddea4691f4c9b170aed74b ]

Commit 61f77eda9bbf ("mm/hugetlb: reduce arch dependent code around
follow_huge_*") broke follow_huge_pmd() on s390, where pmd and pte
layout differ and using pte_page() on a huge pmd will return wrong
results.  Using pmd_page() instead fixes this.

All architectures that were touched by that commit have pmd_page()
defined, so this should not break anything on other architectures.

Fixes: 61f77eda "mm/hugetlb: reduce arch dependent code around follow_huge_*"
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.cz>, Andrea Arcangeli <aarcange@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/arch/arm/mm/hugetlbpage.c b/arch/arm/mm/hugetlbpage.c
index 66781bf..c724124 100644 (file)
--- a/arch/arm/mm/hugetlbpage.c
+++ b/arch/arm/mm/hugetlbpage.c
@@ -36,12 +36,6 @@
  * of type casting from pmd_t * to pte_t *.
  */
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-                             int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pud_huge(pud_t pud)
 {
        return 0;

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 023747b..2de9d2e 100644 (file)
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -38,12 +38,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 }
 #endif
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-                             int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        return !(pmd_val(pmd) & PMD_TABLE_BIT);

diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c
index 76069c1..52b7604 100644 (file)
--- a/arch/ia64/mm/hugetlbpage.c
+++ b/arch/ia64/mm/hugetlbpage.c
@@ -114,12 +114,6 @@ int pud_huge(pud_t pud)
        return 0;
 }
 
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write)
-{
-       return NULL;
-}
-
 void hugetlb_free_pgd_range(struct mmu_gather *tlb,
                        unsigned long addr, unsigned long end,
                        unsigned long floor, unsigned long ceiling)

diff --git a/arch/metag/mm/hugetlbpage.c b/arch/metag/mm/hugetlbpage.c
index 3c32075..7ca80ac 100644 (file)
--- a/arch/metag/mm/hugetlbpage.c
+++ b/arch/metag/mm/hugetlbpage.c
@@ -94,12 +94,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
        return 0;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm,
-                             unsigned long address, int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        return pmd_page_shift(pmd) > PAGE_SHIFT;

diff --git a/arch/mips/mm/hugetlbpage.c b/arch/mips/mm/hugetlbpage.c
index 4ec8ee1..06e0f42 100644 (file)
--- a/arch/mips/mm/hugetlbpage.c
+++ b/arch/mips/mm/hugetlbpage.c
@@ -68,12 +68,6 @@ int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
        return 0;
 }
 
-struct page *
-follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        return (pmd_val(pmd) & _PAGE_HUGE) != 0;
@@ -83,15 +77,3 @@ int pud_huge(pud_t pud)
 {
        return (pud_val(pud) & _PAGE_HUGE) != 0;
 }
-
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-               pmd_t *pmd, int write)
-{
-       struct page *page;
-
-       page = pte_page(*(pte_t *)pmd);
-       if (page)
-               page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
-       return page;
-}

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 6a4a5fc..17e83a0 100644 (file)
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -704,6 +704,14 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
        return NULL;
 }
 
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+               pud_t *pud, int write)
+{
+       BUG();
+       return NULL;
+}
+
 static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
                                      unsigned long sz)
 {

diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index 3c80d2e..210ffed 100644 (file)
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -192,12 +192,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
        return 0;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-                             int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        if (!MACHINE_HAS_HPAGE)
@@ -210,17 +204,3 @@ int pud_huge(pud_t pud)
 {
        return 0;
 }
-
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-                            pmd_t *pmdp, int write)
-{
-       struct page *page;
-
-       if (!MACHINE_HAS_HPAGE)
-               return NULL;
-
-       page = pmd_page(*pmdp);
-       if (page)
-               page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
-       return page;
-}

diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c
index d776234..534bc97 100644 (file)
--- a/arch/sh/mm/hugetlbpage.c
+++ b/arch/sh/mm/hugetlbpage.c
@@ -67,12 +67,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
        return 0;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm,
-                             unsigned long address, int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        return 0;
@@ -82,9 +76,3 @@ int pud_huge(pud_t pud)
 {
        return 0;
 }
-
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-                            pmd_t *pmd, int write)
-{
-       return NULL;
-}

diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index d329537..4242eab 100644 (file)
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -215,12 +215,6 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
        return entry;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm,
-                             unsigned long address, int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        return 0;
@@ -230,9 +224,3 @@ int pud_huge(pud_t pud)
 {
        return 0;
 }
-
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-                            pmd_t *pmd, int write)
-{
-       return NULL;
-}

diff --git a/arch/tile/mm/hugetlbpage.c b/arch/tile/mm/hugetlbpage.c
index e514899..8a00c7b 100644 (file)
--- a/arch/tile/mm/hugetlbpage.c
+++ b/arch/tile/mm/hugetlbpage.c
@@ -150,12 +150,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
        return NULL;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-                             int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
        return !!(pmd_val(pmd) & _PAGE_HUGE_PAGE);
@@ -166,28 +160,6 @@ int pud_huge(pud_t pud)
        return !!(pud_val(pud) & _PAGE_HUGE_PAGE);
 }
 
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-                            pmd_t *pmd, int write)
-{
-       struct page *page;
-
-       page = pte_page(*(pte_t *)pmd);
-       if (page)
-               page += ((address & ~PMD_MASK) >> PAGE_SHIFT);
-       return page;
-}
-
-struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
-                            pud_t *pud, int write)
-{
-       struct page *page;
-
-       page = pte_page(*(pte_t *)pud);
-       if (page)
-               page += ((address & ~PUD_MASK) >> PAGE_SHIFT);
-       return page;
-}
-
 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 {
        return 0;

diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 006cc91..9161f76 100644 (file)
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -52,20 +52,8 @@ int pud_huge(pud_t pud)
        return 0;
 }
 
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-               pmd_t *pmd, int write)
-{
-       return NULL;
-}
 #else
 
-struct page *
-follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
-{
-       return ERR_PTR(-EINVAL);
-}
-
 /*
  * pmd_huge() returns 1 if @pmd is hugetlb related entry, that is normal
  * hugetlb entry or non-present (migration or hwpoisoned) hugetlb entry.

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4cacc6a..e8c0078 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3693,7 +3693,20 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
        return (pte_t *) pmd;
 }
 
-struct page *
+#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
+
+/*
+ * These functions are overwritable if your architecture needs its own
+ * behavior.
+ */
+struct page * __weak
+follow_huge_addr(struct mm_struct *mm, unsigned long address,
+                             int write)
+{
+       return ERR_PTR(-EINVAL);
+}
+
+struct page * __weak
 follow_huge_pmd(struct mm_struct *mm, unsigned long address,
                pmd_t *pmd, int write)
 {
@@ -3707,7 +3720,7 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
        return page;
 }
 
-struct page *
+struct page * __weak
 follow_huge_pud(struct mm_struct *mm, unsigned long address,
                pud_t *pud, int write)
 {
@@ -3719,19 +3732,6 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address,
        return page;
 }
 
-#else /* !CONFIG_ARCH_WANT_GENERAL_HUGETLB */
-
-/* Can be overriden by architectures */
-struct page * __weak
-follow_huge_pud(struct mm_struct *mm, unsigned long address,
-              pud_t *pud, int write)
-{
-       BUG();
-       return NULL;
-}
-
-#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
-
 #ifdef CONFIG_MEMORY_FAILURE
 
 /* Should be called in hugetlb_lock */