+ powerpc-book3s64-mm-enable-transparent-pud-hugepage.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: powerpc/book3s64/mm: enable transparent pud hugepage
has been added to the -mm mm-unstable branch.  Its filename is
     powerpc-book3s64-mm-enable-transparent-pud-hugepage.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/powerpc-book3s64-mm-enable-transparent-pud-hugepage.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Subject: powerpc/book3s64/mm: enable transparent pud hugepage
Date: Tue, 25 Jul 2023 00:37:55 +0530

This is enabled only with radix translation and 1G hugepage size.  This
will be used with devdax device memory with a namespace alignment of 1G.

Anon transparent hugepage is not supported even though we do have helpers
checking pud_trans_huge().  We should never find that return true.  The
only expected pte bit combination is _PAGE_PTE | _PAGE_DEVMAP.

Some of the helpers are never expected to get called on hash translation
and hence is marked to call BUG() in such a case.

Link: https://lkml.kernel.org/r/20230724190759.483013-10-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/powerpc/include/asm/book3s/64/hash.h           |    9 
 arch/powerpc/include/asm/book3s/64/pgtable.h        |  155 +++++++++-
 arch/powerpc/include/asm/book3s/64/radix.h          |   36 ++
 arch/powerpc/include/asm/book3s/64/tlbflush-radix.h |    2 
 arch/powerpc/include/asm/book3s/64/tlbflush.h       |    8 
 arch/powerpc/mm/book3s64/pgtable.c                  |   78 +++++
 arch/powerpc/mm/book3s64/radix_pgtable.c            |   28 +
 arch/powerpc/mm/book3s64/radix_tlb.c                |    7 
 arch/powerpc/platforms/Kconfig.cputype              |    1 
 include/trace/events/thp.h                          |   10 
 10 files changed, 323 insertions(+), 11 deletions(-)

--- a/arch/powerpc/include/asm/book3s/64/hash.h~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/include/asm/book3s/64/hash.h
@@ -138,7 +138,16 @@ static inline int hash__pmd_same(pmd_t p
 }
 
 #define	hash__pmd_bad(pmd)		(pmd_val(pmd) & H_PMD_BAD_BITS)
+
+/*
+ * pud comparison that will work with both pte and page table pointer.
+ */
+static inline int hash__pud_same(pud_t pud_a, pud_t pud_b)
+{
+	return (((pud_raw(pud_a) ^ pud_raw(pud_b)) & ~cpu_to_be64(_PAGE_HPTEFLAGS)) == 0);
+}
 #define	hash__pud_bad(pud)		(pud_val(pud) & H_PUD_BAD_BITS)
+
 static inline int hash__p4d_bad(p4d_t p4d)
 {
 	return (p4d_val(p4d) == 0);
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -921,8 +921,29 @@ static inline pud_t pte_pud(pte_t pte)
 {
 	return __pud_raw(pte_raw(pte));
 }
+
+static inline pte_t *pudp_ptep(pud_t *pud)
+{
+	return (pte_t *)pud;
+}
+
+#define pud_pfn(pud)		pte_pfn(pud_pte(pud))
+#define pud_dirty(pud)		pte_dirty(pud_pte(pud))
+#define pud_young(pud)		pte_young(pud_pte(pud))
+#define pud_mkold(pud)		pte_pud(pte_mkold(pud_pte(pud)))
+#define pud_wrprotect(pud)	pte_pud(pte_wrprotect(pud_pte(pud)))
+#define pud_mkdirty(pud)	pte_pud(pte_mkdirty(pud_pte(pud)))
+#define pud_mkclean(pud)	pte_pud(pte_mkclean(pud_pte(pud)))
+#define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
+#define pud_mkwrite(pud)	pte_pud(pte_mkwrite(pud_pte(pud)))
 #define pud_write(pud)		pte_write(pud_pte(pud))
 
+#ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
+#define pud_soft_dirty(pmd)    pte_soft_dirty(pud_pte(pud))
+#define pud_mksoft_dirty(pmd)  pte_pud(pte_mksoft_dirty(pud_pte(pud)))
+#define pud_clear_soft_dirty(pmd) pte_pud(pte_clear_soft_dirty(pud_pte(pud)))
+#endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
+
 static inline int pud_bad(pud_t pud)
 {
 	if (radix_enabled())
@@ -1115,15 +1136,24 @@ static inline bool pmd_access_permitted(
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 extern pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot);
+extern pud_t pfn_pud(unsigned long pfn, pgprot_t pgprot);
 extern pmd_t mk_pmd(struct page *page, pgprot_t pgprot);
 extern pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot);
 extern void set_pmd_at(struct mm_struct *mm, unsigned long addr,
 		       pmd_t *pmdp, pmd_t pmd);
+extern void set_pud_at(struct mm_struct *mm, unsigned long addr,
+		       pud_t *pudp, pud_t pud);
+
 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
 					unsigned long addr, pmd_t *pmd)
 {
 }
 
+static inline void update_mmu_cache_pud(struct vm_area_struct *vma,
+					unsigned long addr, pud_t *pud)
+{
+}
+
 extern int hash__has_transparent_hugepage(void);
 static inline int has_transparent_hugepage(void)
 {
@@ -1133,6 +1163,14 @@ static inline int has_transparent_hugepa
 }
 #define has_transparent_hugepage has_transparent_hugepage
 
+static inline int has_transparent_pud_hugepage(void)
+{
+	if (radix_enabled())
+		return radix__has_transparent_pud_hugepage();
+	return 0;
+}
+#define has_transparent_pud_hugepage has_transparent_pud_hugepage
+
 static inline unsigned long
 pmd_hugepage_update(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp,
 		    unsigned long clr, unsigned long set)
@@ -1142,6 +1180,16 @@ pmd_hugepage_update(struct mm_struct *mm
 	return hash__pmd_hugepage_update(mm, addr, pmdp, clr, set);
 }
 
+static inline unsigned long
+pud_hugepage_update(struct mm_struct *mm, unsigned long addr, pud_t *pudp,
+		    unsigned long clr, unsigned long set)
+{
+	if (radix_enabled())
+		return radix__pud_hugepage_update(mm, addr, pudp, clr, set);
+	BUG();
+	return pud_val(*pudp);
+}
+
 /*
  * returns true for pmd migration entries, THP, devmap, hugetlb
  * But compile time dependent on THP config
@@ -1151,6 +1199,11 @@ static inline int pmd_large(pmd_t pmd)
 	return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE));
 }
 
+static inline int pud_large(pud_t pud)
+{
+	return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE));
+}
+
 /*
  * For radix we should always find H_PAGE_HASHPTE zero. Hence
  * the below will work for radix too
@@ -1166,6 +1219,17 @@ static inline int __pmdp_test_and_clear_
 	return ((old & _PAGE_ACCESSED) != 0);
 }
 
+static inline int __pudp_test_and_clear_young(struct mm_struct *mm,
+					      unsigned long addr, pud_t *pudp)
+{
+	unsigned long old;
+
+	if ((pud_raw(*pudp) & cpu_to_be64(_PAGE_ACCESSED | H_PAGE_HASHPTE)) == 0)
+		return 0;
+	old = pud_hugepage_update(mm, addr, pudp, _PAGE_ACCESSED, 0);
+	return ((old & _PAGE_ACCESSED) != 0);
+}
+
 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
 static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 				      pmd_t *pmdp)
@@ -1174,6 +1238,14 @@ static inline void pmdp_set_wrprotect(st
 		pmd_hugepage_update(mm, addr, pmdp, _PAGE_WRITE, 0);
 }
 
+#define __HAVE_ARCH_PUDP_SET_WRPROTECT
+static inline void pudp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
+				      pud_t *pudp)
+{
+	if (pud_write(*pudp))
+		pud_hugepage_update(mm, addr, pudp, _PAGE_WRITE, 0);
+}
+
 /*
  * Only returns true for a THP. False for pmd migration entry.
  * We also need to return true when we come across a pte that
@@ -1195,6 +1267,17 @@ static inline int pmd_trans_huge(pmd_t p
 	return hash__pmd_trans_huge(pmd);
 }
 
+static inline int pud_trans_huge(pud_t pud)
+{
+	if (!pud_present(pud))
+		return false;
+
+	if (radix_enabled())
+		return radix__pud_trans_huge(pud);
+	return 0;
+}
+
+
 #define __HAVE_ARCH_PMD_SAME
 static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
 {
@@ -1203,6 +1286,15 @@ static inline int pmd_same(pmd_t pmd_a,
 	return hash__pmd_same(pmd_a, pmd_b);
 }
 
+#define pud_same pud_same
+static inline int pud_same(pud_t pud_a, pud_t pud_b)
+{
+	if (radix_enabled())
+		return radix__pud_same(pud_a, pud_b);
+	return hash__pud_same(pud_a, pud_b);
+}
+
+
 static inline pmd_t __pmd_mkhuge(pmd_t pmd)
 {
 	if (radix_enabled())
@@ -1210,6 +1302,14 @@ static inline pmd_t __pmd_mkhuge(pmd_t p
 	return hash__pmd_mkhuge(pmd);
 }
 
+static inline pud_t __pud_mkhuge(pud_t pud)
+{
+	if (radix_enabled())
+		return radix__pud_mkhuge(pud);
+	BUG();
+	return pud;
+}
+
 /*
  * pfn_pmd return a pmd_t that can be used as pmd pte entry.
  */
@@ -1225,14 +1325,34 @@ static inline pmd_t pmd_mkhuge(pmd_t pmd
 	return pmd;
 }
 
+static inline pud_t pud_mkhuge(pud_t pud)
+{
+#ifdef CONFIG_DEBUG_VM
+	if (radix_enabled())
+		WARN_ON((pud_raw(pud) & cpu_to_be64(_PAGE_PTE)) == 0);
+	else
+		WARN_ON(1);
+#endif
+	return pud;
+}
+
+
 #define __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);
+#define __HAVE_ARCH_PUDP_SET_ACCESS_FLAGS
+extern int pudp_set_access_flags(struct vm_area_struct *vma,
+				 unsigned long address, pud_t *pudp,
+				 pud_t entry, int dirty);
 
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
 extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 				     unsigned long address, pmd_t *pmdp);
+#define __HAVE_ARCH_PUDP_TEST_AND_CLEAR_YOUNG
+extern int pudp_test_and_clear_young(struct vm_area_struct *vma,
+				     unsigned long address, pud_t *pudp);
+
 
 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
@@ -1243,6 +1363,16 @@ static inline pmd_t pmdp_huge_get_and_cl
 	return hash__pmdp_huge_get_and_clear(mm, addr, pmdp);
 }
 
+#define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR
+static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm,
+					    unsigned long addr, pud_t *pudp)
+{
+	if (radix_enabled())
+		return radix__pudp_huge_get_and_clear(mm, addr, pudp);
+	BUG();
+	return *pudp;
+}
+
 static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
 					unsigned long address, pmd_t *pmdp)
 {
@@ -1257,6 +1387,11 @@ pmd_t pmdp_huge_get_and_clear_full(struc
 				   unsigned long addr,
 				   pmd_t *pmdp, int full);
 
+#define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR_FULL
+pud_t pudp_huge_get_and_clear_full(struct vm_area_struct *vma,
+				   unsigned long addr,
+				   pud_t *pudp, int full);
+
 #define __HAVE_ARCH_PGTABLE_DEPOSIT
 static inline void pgtable_trans_huge_deposit(struct mm_struct *mm,
 					      pmd_t *pmdp, pgtable_t pgtable)
@@ -1305,6 +1440,14 @@ static inline pmd_t pmd_mkdevmap(pmd_t p
 	return hash__pmd_mkdevmap(pmd);
 }
 
+static inline pud_t pud_mkdevmap(pud_t pud)
+{
+	if (radix_enabled())
+		return radix__pud_mkdevmap(pud);
+	BUG();
+	return pud;
+}
+
 static inline int pmd_devmap(pmd_t pmd)
 {
 	return pte_devmap(pmd_pte(pmd));
@@ -1312,7 +1455,7 @@ static inline int pmd_devmap(pmd_t pmd)
 
 static inline int pud_devmap(pud_t pud)
 {
-	return 0;
+	return pte_devmap(pud_pte(pud));
 }
 
 static inline int pgd_devmap(pgd_t pgd)
@@ -1321,16 +1464,6 @@ static inline int pgd_devmap(pgd_t pgd)
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
-static inline int pud_pfn(pud_t pud)
-{
-	/*
-	 * Currently all calls to pud_pfn() are gated around a pud_devmap()
-	 * check so this should never be used. If it grows another user we
-	 * want to know about it.
-	 */
-	BUILD_BUG();
-	return 0;
-}
 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
 pte_t ptep_modify_prot_start(struct vm_area_struct *, unsigned long, pte_t *);
 void ptep_modify_prot_commit(struct vm_area_struct *, unsigned long,
--- a/arch/powerpc/include/asm/book3s/64/radix.h~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/include/asm/book3s/64/radix.h
@@ -250,6 +250,10 @@ static inline int radix__pud_bad(pud_t p
 	return !!(pud_val(pud) & RADIX_PUD_BAD_BITS);
 }
 
+static inline int radix__pud_same(pud_t pud_a, pud_t pud_b)
+{
+	return ((pud_raw(pud_a) ^ pud_raw(pud_b)) == 0);
+}
 
 static inline int radix__p4d_bad(p4d_t p4d)
 {
@@ -268,9 +272,22 @@ static inline pmd_t radix__pmd_mkhuge(pm
 	return __pmd(pmd_val(pmd) | _PAGE_PTE);
 }
 
+static inline int radix__pud_trans_huge(pud_t pud)
+{
+	return (pud_val(pud) & (_PAGE_PTE | _PAGE_DEVMAP)) == _PAGE_PTE;
+}
+
+static inline pud_t radix__pud_mkhuge(pud_t pud)
+{
+	return __pud(pud_val(pud) | _PAGE_PTE);
+}
+
 extern unsigned long radix__pmd_hugepage_update(struct mm_struct *mm, unsigned long addr,
 					  pmd_t *pmdp, unsigned long clr,
 					  unsigned long set);
+extern unsigned long radix__pud_hugepage_update(struct mm_struct *mm, unsigned long addr,
+						pud_t *pudp, unsigned long clr,
+						unsigned long set);
 extern pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma,
 				  unsigned long address, pmd_t *pmdp);
 extern void radix__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
@@ -278,6 +295,9 @@ extern void radix__pgtable_trans_huge_de
 extern pgtable_t radix__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
 extern pmd_t radix__pmdp_huge_get_and_clear(struct mm_struct *mm,
 				      unsigned long addr, pmd_t *pmdp);
+pud_t radix__pudp_huge_get_and_clear(struct mm_struct *mm,
+				     unsigned long addr, pud_t *pudp);
+
 static inline int radix__has_transparent_hugepage(void)
 {
 	/* For radix 2M at PMD level means thp */
@@ -285,6 +305,14 @@ static inline int radix__has_transparent
 		return 1;
 	return 0;
 }
+
+static inline int radix__has_transparent_pud_hugepage(void)
+{
+	/* For radix 1G at PUD level means pud hugepage support */
+	if (mmu_psize_defs[MMU_PAGE_1G].shift == PUD_SHIFT)
+		return 1;
+	return 0;
+}
 #endif
 
 static inline pmd_t radix__pmd_mkdevmap(pmd_t pmd)
@@ -292,9 +320,17 @@ static inline pmd_t radix__pmd_mkdevmap(
 	return __pmd(pmd_val(pmd) | (_PAGE_PTE | _PAGE_DEVMAP));
 }
 
+static inline pud_t radix__pud_mkdevmap(pud_t pud)
+{
+	return __pud(pud_val(pud) | (_PAGE_PTE | _PAGE_DEVMAP));
+}
+
+struct vmem_altmap;
 extern int __meminit radix__vmemmap_create_mapping(unsigned long start,
 					     unsigned long page_size,
 					     unsigned long phys);
+int __meminit radix__vmemmap_populate(unsigned long start, unsigned long end,
+				      int node, struct vmem_altmap *altmap);
 extern void radix__vmemmap_remove_mapping(unsigned long start,
 				    unsigned long page_size);
 
--- a/arch/powerpc/include/asm/book3s/64/tlbflush.h~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/include/asm/book3s/64/tlbflush.h
@@ -51,6 +51,14 @@ static inline void flush_pmd_tlb_range(s
 		radix__flush_pmd_tlb_range(vma, start, end);
 }
 
+#define __HAVE_ARCH_FLUSH_PUD_TLB_RANGE
+static inline void flush_pud_tlb_range(struct vm_area_struct *vma,
+				       unsigned long start, unsigned long end)
+{
+	if (radix_enabled())
+		radix__flush_pud_tlb_range(vma, start, end);
+}
+
 #define __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE
 static inline void flush_hugetlb_tlb_range(struct vm_area_struct *vma,
 					   unsigned long start,
--- a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h
@@ -68,6 +68,8 @@ void radix__flush_tlb_pwc_range_psize(st
 				      unsigned long end, int psize);
 extern void radix__flush_pmd_tlb_range(struct vm_area_struct *vma,
 				       unsigned long start, unsigned long end);
+extern void radix__flush_pud_tlb_range(struct vm_area_struct *vma,
+				       unsigned long start, unsigned long end);
 extern void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 			    unsigned long end);
 extern void radix__flush_tlb_kernel_range(unsigned long start, unsigned long end);
--- a/arch/powerpc/mm/book3s64/pgtable.c~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/mm/book3s64/pgtable.c
@@ -64,11 +64,39 @@ int pmdp_set_access_flags(struct vm_area
 	return changed;
 }
 
+int pudp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
+			  pud_t *pudp, pud_t entry, int dirty)
+{
+	int changed;
+#ifdef CONFIG_DEBUG_VM
+	WARN_ON(!pud_devmap(*pudp));
+	assert_spin_locked(pud_lockptr(vma->vm_mm, pudp));
+#endif
+	changed = !pud_same(*(pudp), entry);
+	if (changed) {
+		/*
+		 * We can use MMU_PAGE_1G here, because only radix
+		 * path look at the psize.
+		 */
+		__ptep_set_access_flags(vma, pudp_ptep(pudp),
+					pud_pte(entry), address, MMU_PAGE_1G);
+	}
+	return changed;
+}
+
+
 int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 			      unsigned long address, pmd_t *pmdp)
 {
 	return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp);
 }
+
+int pudp_test_and_clear_young(struct vm_area_struct *vma,
+			      unsigned long address, pud_t *pudp)
+{
+	return __pudp_test_and_clear_young(vma->vm_mm, address, pudp);
+}
+
 /*
  * set a new huge pmd. We should not be called for updating
  * an existing pmd entry. That should go via pmd_hugepage_update.
@@ -90,6 +118,23 @@ void set_pmd_at(struct mm_struct *mm, un
 	return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
 }
 
+void set_pud_at(struct mm_struct *mm, unsigned long addr,
+		pud_t *pudp, pud_t pud)
+{
+#ifdef CONFIG_DEBUG_VM
+	/*
+	 * Make sure hardware valid bit is not set. We don't do
+	 * tlb flush for this update.
+	 */
+
+	WARN_ON(pte_hw_valid(pud_pte(*pudp)));
+	assert_spin_locked(pud_lockptr(mm, pudp));
+	WARN_ON(!(pud_large(pud)));
+#endif
+	trace_hugepage_set_pud(addr, pud_val(pud));
+	return set_pte_at(mm, addr, pudp_ptep(pudp), pud_pte(pud));
+}
+
 static void do_serialize(void *arg)
 {
 	/* We've taken the IPI, so try to trim the mask while here */
@@ -147,11 +192,35 @@ pmd_t pmdp_huge_get_and_clear_full(struc
 	return pmd;
 }
 
+pud_t pudp_huge_get_and_clear_full(struct vm_area_struct *vma,
+				   unsigned long addr, pud_t *pudp, int full)
+{
+	pud_t pud;
+
+	VM_BUG_ON(addr & ~HPAGE_PMD_MASK);
+	VM_BUG_ON((pud_present(*pudp) && !pud_devmap(*pudp)) ||
+		  !pud_present(*pudp));
+	pud = pudp_huge_get_and_clear(vma->vm_mm, addr, pudp);
+	/*
+	 * if it not a fullmm flush, then we can possibly end up converting
+	 * this PMD pte entry to a regular level 0 PTE by a parallel page fault.
+	 * Make sure we flush the tlb in this case.
+	 */
+	if (!full)
+		flush_pud_tlb_range(vma, addr, addr + HPAGE_PUD_SIZE);
+	return pud;
+}
+
 static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot)
 {
 	return __pmd(pmd_val(pmd) | pgprot_val(pgprot));
 }
 
+static pud_t pud_set_protbits(pud_t pud, pgprot_t pgprot)
+{
+	return __pud(pud_val(pud) | pgprot_val(pgprot));
+}
+
 /*
  * At some point we should be able to get rid of
  * pmd_mkhuge() and mk_huge_pmd() when we update all the
@@ -166,6 +235,15 @@ pmd_t pfn_pmd(unsigned long pfn, pgprot_
 	return __pmd_mkhuge(pmd_set_protbits(__pmd(pmdv), pgprot));
 }
 
+pud_t pfn_pud(unsigned long pfn, pgprot_t pgprot)
+{
+	unsigned long pudv;
+
+	pudv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK;
+
+	return __pud_mkhuge(pud_set_protbits(__pud(pudv), pgprot));
+}
+
 pmd_t mk_pmd(struct page *page, pgprot_t pgprot)
 {
 	return pfn_pmd(page_to_pfn(page), pgprot);
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -967,6 +967,23 @@ unsigned long radix__pmd_hugepage_update
 	return old;
 }
 
+unsigned long radix__pud_hugepage_update(struct mm_struct *mm, unsigned long addr,
+					 pud_t *pudp, unsigned long clr,
+					 unsigned long set)
+{
+	unsigned long old;
+
+#ifdef CONFIG_DEBUG_VM
+	WARN_ON(!pud_devmap(*pudp));
+	assert_spin_locked(pud_lockptr(mm, pudp));
+#endif
+
+	old = radix__pte_update(mm, addr, pudp_ptep(pudp), clr, set, 1);
+	trace_hugepage_update_pud(addr, old, clr, set);
+
+	return old;
+}
+
 pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
 			pmd_t *pmdp)
 
@@ -1043,6 +1060,17 @@ pmd_t radix__pmdp_huge_get_and_clear(str
 	return old_pmd;
 }
 
+pud_t radix__pudp_huge_get_and_clear(struct mm_struct *mm,
+				     unsigned long addr, pud_t *pudp)
+{
+	pud_t old_pud;
+	unsigned long old;
+
+	old = radix__pud_hugepage_update(mm, addr, pudp, ~0UL, 0);
+	old_pud = __pud(old);
+	return old_pud;
+}
+
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
 void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep,
--- a/arch/powerpc/mm/book3s64/radix_tlb.c~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -1465,6 +1465,13 @@ void radix__flush_pmd_tlb_range(struct v
 }
 EXPORT_SYMBOL(radix__flush_pmd_tlb_range);
 
+void radix__flush_pud_tlb_range(struct vm_area_struct *vma,
+				unsigned long start, unsigned long end)
+{
+	radix__flush_tlb_range_psize(vma->vm_mm, start, end, MMU_PAGE_1G);
+}
+EXPORT_SYMBOL(radix__flush_pud_tlb_range);
+
 void radix__flush_tlb_all(void)
 {
 	unsigned long rb,prs,r,rs;
--- a/arch/powerpc/platforms/Kconfig.cputype~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/arch/powerpc/platforms/Kconfig.cputype
@@ -94,6 +94,7 @@ config PPC_BOOK3S_64
 	select PPC_FPU
 	select PPC_HAVE_PMU_SUPPORT
 	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
+	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
 	select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
 	select ARCH_ENABLE_SPLIT_PMD_PTLOCK
 	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
--- a/include/trace/events/thp.h~powerpc-book3s64-mm-enable-transparent-pud-hugepage
+++ a/include/trace/events/thp.h
@@ -30,6 +30,11 @@ DEFINE_EVENT(hugepage_set, hugepage_set_
 	    TP_ARGS(addr, pmd)
 );
 
+DEFINE_EVENT(hugepage_set, hugepage_set_pud,
+	    TP_PROTO(unsigned long addr, unsigned long pud),
+	    TP_ARGS(addr, pud)
+);
+
 DECLARE_EVENT_CLASS(hugepage_update,
 
 	    TP_PROTO(unsigned long addr, unsigned long pte, unsigned long clr, unsigned long set),
@@ -57,6 +62,11 @@ DEFINE_EVENT(hugepage_update, hugepage_u
 	    TP_ARGS(addr, pmd, clr, set)
 );
 
+DEFINE_EVENT(hugepage_update, hugepage_update_pud,
+	    TP_PROTO(unsigned long addr, unsigned long pud, unsigned long clr, unsigned long set),
+	    TP_ARGS(addr, pud, clr, set)
+);
+
 DECLARE_EVENT_CLASS(migration_pmd,
 
 		TP_PROTO(unsigned long addr, unsigned long pmd),
_

Patches currently in -mm which might be from aneesh.kumar@linux.ibm.com are

mm-hugepage-pud-allow-arch-specific-helper-function-to-check-huge-page-pud-support.patch
mm-change-pudp_huge_get_and_clear_full-take-vm_area_struct-as-arg.patch
mm-vmemmap-improve-vmemmap_can_optimize-and-allow-architectures-to-override.patch
mm-vmemmap-allow-architectures-to-override-how-vmemmap-optimization-works.patch
mm-add-pud_same-similar-to-__have_arch_p4d_same.patch
mm-huge-pud-use-transparent-huge-pud-helpers-only-with-config_transparent_hugepage.patch
mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization.patch
powerpc-mm-trace-convert-trace-event-to-trace-event-class.patch
powerpc-book3s64-mm-enable-transparent-pud-hugepage.patch
powerpc-book3s64-vmemmap-switch-radix-to-use-a-different-vmemmap-handling-function.patch
powerpc-book3s64-radix-add-support-for-vmemmap-optimization-for-radix.patch
powerpc-book3s64-radix-remove-mmu_vmemmap_psize.patch
powerpc-book3s64-radix-add-debug-message-to-give-more-details-of-vmemmap-allocation.patch