[PATCH mm-unstable RFC v4 6/7] mm/huge_memory: make move_huge_pmd() use has_deposited_pgtable()

[Yin Tirui]

Use has_deposited_pgtable() in move_huge_pmd() to decide whether
pmd_move_must_withdraw() should move a deposited pgtable instead of
using the VMA type.

PowerPC radix follows the generic rule.  PowerPC hash keeps returning
true.

Signed-off-by: Yin Tirui <yintirui@xxxxxxxxxx>
---
 arch/powerpc/include/asm/book3s/64/pgtable.h |  5 ++---
 arch/powerpc/mm/book3s64/pgtable.c           | 11 +++++------
 mm/huge_memory.c                             | 20 ++++++++++++--------
 3 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index b6629c041e75..a0042cacac8d 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -1424,9 +1424,8 @@ extern pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
 
 #define pmd_move_must_withdraw pmd_move_must_withdraw
 struct spinlock;
-extern int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
-				  struct spinlock *old_pmd_ptl,
-				  struct vm_area_struct *vma);
+extern bool pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
+		struct spinlock *old_pmd_ptl, bool has_deposit);
 /*
  * Hash translation mode use the deposited table to store hash pte
  * slot information.
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
index 85ab6723c8f2..4c45b5762d57 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -548,15 +548,14 @@ void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
  * pmd page. Hence if we have different pmd page we need to withdraw during pmd
  * move.
  *
- * With hash we use deposited table always irrespective of anon or not.
- * With radix we use deposited table only for anonymous mapping.
+ * With hash we use deposited table always irrespective of has_deposit or not.
+ * With radix we use the same rule as the generic implementation.
  */
-int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
-			   struct spinlock *old_pmd_ptl,
-			   struct vm_area_struct *vma)
+bool pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
+		struct spinlock *old_pmd_ptl, bool has_deposit)
 {
 	if (radix_enabled())
-		return (new_pmd_ptl != old_pmd_ptl) && vma_is_anonymous(vma);
+		return (new_pmd_ptl != old_pmd_ptl) && has_deposit;
 
 	return true;
 }
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 8cd77389d52f..be9b637c813b 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2552,17 +2552,14 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 }
 
 #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)
+static inline bool pmd_move_must_withdraw(spinlock_t *new_pmd_ptl,
+		spinlock_t *old_pmd_ptl, bool has_deposit)
 {
 	/*
 	 * 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);
+	return (new_pmd_ptl != old_pmd_ptl) && has_deposit;
 }
 #endif
 
@@ -2595,8 +2592,11 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
 {
 	spinlock_t *old_ptl, *new_ptl;
 	pmd_t pmd;
+	struct folio *folio = NULL;
 	struct mm_struct *mm = vma->vm_mm;
 	bool force_flush = false;
+	bool has_deposit;
+	bool is_present;
 
 	/*
 	 * The destination pmd shouldn't be established, free_pgtables()
@@ -2618,11 +2618,15 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
 		if (new_ptl != old_ptl)
 			spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING);
 		pmd = pmdp_huge_get_and_clear(mm, old_addr, old_pmd);
-		if (pmd_present(pmd))
+		is_present = pmd_present(pmd);
+		if (is_present)
 			force_flush = true;
 		VM_BUG_ON(!pmd_none(*new_pmd));
 
-		if (pmd_move_must_withdraw(new_ptl, old_ptl, vma)) {
+		folio = normal_or_softleaf_folio_pmd(vma, old_addr, pmd, is_present);
+		has_deposit = has_deposited_pgtable(vma, pmd, folio);
+
+		if (pmd_move_must_withdraw(new_ptl, old_ptl, has_deposit)) {
 			pgtable_t pgtable;
 			pgtable = pgtable_trans_huge_withdraw(mm, old_pmd);
 			pgtable_trans_huge_deposit(mm, new_pmd, pgtable);
-- 
2.43.0