Architectures like ppc64 want to use page table deposit/withraw
even with huge pmd dax entries. Allow arch to override the
vma_is_anonymous check by moving that to pmd_move_must_withdraw
function
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
---
* Changes from V1:
Fix build error with x86 config
arch/powerpc/include/asm/book3s/64/pgtable.h | 3 ++-
include/asm-generic/pgtable.h | 12 ------------
mm/huge_memory.c | 18 ++++++++++++++++--
3 files changed, 18 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 9fd77f8794a0..700301bc5190 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -1009,7 +1009,8 @@ static inline void pmdp_huge_split_prepare(struct vm_area_struct *vma,
#define pmd_move_must_withdraw pmd_move_must_withdraw
struct spinlock;
static inline int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
- struct spinlock *old_pmd_ptl)
+ struct spinlock *old_pmd_ptl,
+ struct vm_area_struct *vma)
{
if (radix_enabled())
return false;
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index c4f8fd2fd384..324990273ad2 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -653,18 +653,6 @@ static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
}
#endif
-#ifndef pmd_move_must_withdraw
-static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl,
- spinlock_t *old_pmd_ptl)
-{
- /*
- * With split pmd lock we also need to move preallocated
- * PTE page table if new_pmd is on different PMD page table.
- */
- return new_pmd_ptl != old_pmd_ptl;
-}
-#endif
-
/*
* This function is meant to be used by sites walking pagetables with
* the mmap_sem hold in read mode to protect against MADV_DONTNEED and
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index cdcd25cb30fe..54f265ec902e 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1424,6 +1424,21 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
return 1;
}
+#ifndef pmd_move_must_withdraw
+static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl,
+ spinlock_t *old_pmd_ptl,
+ struct vm_area_struct *vma)
+{
+ /*
+ * With split pmd lock we also need to move preallocated
+ * PTE page table if new_pmd is on different PMD page table.
+ *
+ * We also don't deposit and withdraw tables for file pages.
+ */
+ return (new_pmd_ptl != old_pmd_ptl) && vma_is_anonymous(vma);
+}
+#endif
+
bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
unsigned long new_addr, unsigned long old_end,
pmd_t *old_pmd, pmd_t *new_pmd)
@@ -1458,8 +1473,7 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
pmd = pmdp_huge_get_and_clear(mm, old_addr, old_pmd);
VM_BUG_ON(!pmd_none(*new_pmd));
- if (pmd_move_must_withdraw(new_ptl, old_ptl) &&
- vma_is_anonymous(vma)) {
+ if (pmd_move_must_withdraw(new_ptl, old_ptl, vma)) {
pgtable_t pgtable;
pgtable = pgtable_trans_huge_withdraw(mm, old_pmd);
pgtable_trans_huge_deposit(mm, new_pmd, pgtable);
--
2.10.2
--
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