[PATCHv2 06/29] mm: convert generic code to 5-level paging

From: Kirill A. Shutemov
Date: Mon Dec 26 2016 - 20:57:31 EST

Convers all non-architecture-specific code to 5-level paging.

It's mosly mechanical adding handling one more page table level in
places where we deal with pud_t.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
drivers/misc/sgi-gru/grufault.c | 9 +-
fs/userfaultfd.c | 6 +-
include/asm-generic/pgtable.h | 48 +++++++++-
include/linux/hugetlb.h | 5 +-
include/linux/kasan.h | 1 +
include/linux/mm.h | 31 ++++--
lib/ioremap.c | 39 +++++++-
mm/gup.c | 46 +++++++--
mm/huge_memory.c | 7 +-
mm/hugetlb.c | 29 +++---
mm/kasan/kasan_init.c | 35 ++++++-
mm/memory.c | 207 +++++++++++++++++++++++++++++++++-------
mm/mlock.c | 1 +
mm/mprotect.c | 26 ++++-
mm/mremap.c | 13 ++-
mm/pagewalk.c | 32 ++++++-
mm/pgtable-generic.c | 6 ++
mm/rmap.c | 13 ++-
mm/sparse-vmemmap.c | 22 ++++-
mm/swapfile.c | 26 ++++-
mm/userfaultfd.c | 23 +++--
mm/vmalloc.c | 81 ++++++++++++----
22 files changed, 586 insertions(+), 120 deletions(-)

diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c
index 6fb773dbcd0c..93be82fc338a 100644
--- a/drivers/misc/sgi-gru/grufault.c
+++ b/drivers/misc/sgi-gru/grufault.c
@@ -219,15 +219,20 @@ static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr,
int write, unsigned long *paddr, int *pageshift)
{
pgd_t *pgdp;
- pmd_t *pmdp;
+ p4d_t *p4dp;
pud_t *pudp;
+ pmd_t *pmdp;
pte_t pte;

pgdp = pgd_offset(vma->vm_mm, vaddr);
if (unlikely(pgd_none(*pgdp)))
goto err;

- pudp = pud_offset(pgdp, vaddr);
+ p4dp = p4d_offset(pgdp, vaddr);
+ if (unlikely(p4d_none(*p4dp)))
+ goto err;
+
+ pudp = pud_offset(p4dp, vaddr);
if (unlikely(pud_none(*pudp)))
goto err;

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index d96e2f30084b..20e04bd11654 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -195,6 +195,7 @@ static inline bool userfaultfd_must_wait(struct userfaultfd_ctx *ctx,
{
struct mm_struct *mm = ctx->mm;
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd, _pmd;
pte_t *pte;
@@ -205,7 +206,10 @@ static inline bool userfaultfd_must_wait(struct userfaultfd_ctx *ctx,
pgd = pgd_offset(mm, address);
if (!pgd_present(*pgd))
goto out;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (!p4d_present(*p4d))
+ goto out;
+ pud = pud_offset(p4d, address);
if (!pud_present(*pud))
goto out;
pmd = pmd_offset(pud, address);
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 18af2bcefe6a..dc6a54318cf5 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -10,9 +10,9 @@
#include <linux/bug.h>
#include <linux/errno.h>

-#if 4 - defined(__PAGETABLE_PUD_FOLDED) - defined(__PAGETABLE_PMD_FOLDED) != \
- CONFIG_PGTABLE_LEVELS
-#error CONFIG_PGTABLE_LEVELS is not consistent with __PAGETABLE_{PUD,PMD}_FOLDED
+#if 5 - defined(__PAGETABLE_P4D_FOLDED) - defined(__PAGETABLE_PUD_FOLDED) - \
+ defined(__PAGETABLE_PMD_FOLDED) != CONFIG_PGTABLE_LEVELS
+#error CONFIG_PGTABLE_LEVELS is not consistent with __PAGETABLE_{P4D,PUD,PMD}_FOLDED
#endif

/*
@@ -339,6 +339,13 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
(__boundary - 1 < (end) - 1)? __boundary: (end); \
})

+#ifndef p4d_addr_end
+#define p4d_addr_end(addr, end) \
+({ unsigned long __boundary = ((addr) + P4D_SIZE) & P4D_MASK; \
+ (__boundary - 1 < (end) - 1)? __boundary: (end); \
+})
+#endif
+
#ifndef pud_addr_end
#define pud_addr_end(addr, end) \
({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \
@@ -359,6 +366,7 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
* Do the tests inline, but report and clear the bad entry in mm/memory.c.
*/
void pgd_clear_bad(pgd_t *);
+void p4d_clear_bad(p4d_t *);
void pud_clear_bad(pud_t *);
void pmd_clear_bad(pmd_t *);

@@ -373,6 +381,17 @@ static inline int pgd_none_or_clear_bad(pgd_t *pgd)
return 0;
}

+static inline int p4d_none_or_clear_bad(p4d_t *p4d)
+{
+ if (p4d_none(*p4d))
+ return 1;
+ if (unlikely(p4d_bad(*p4d))) {
+ p4d_clear_bad(p4d);
+ return 1;
+ }
+ return 0;
+}
+
static inline int pud_none_or_clear_bad(pud_t *pud)
{
if (pud_none(*pud))
@@ -750,11 +769,30 @@ static inline int pmd_protnone(pmd_t pmd)
#endif /* CONFIG_MMU */

#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+
+#ifndef __PAGETABLE_P4D_FOLDED
+int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot);
+int p4d_clear_huge(p4d_t *p4d);
+#else
+static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
+{
+ return 0;
+}
+static inline int p4d_clear_huge(p4d_t *p4d)
+{
+ return 0;
+}
+#endif /* !__PAGETABLE_P4D_FOLDED */
+
int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot);
int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot);
int pud_clear_huge(pud_t *pud);
int pmd_clear_huge(pmd_t *pmd);
#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
+{
+ return 0;
+}
static inline int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
{
return 0;
@@ -763,6 +801,10 @@ static inline int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
{
return 0;
}
+static inline int p4d_clear_huge(p4d_t *p4d)
+{
+ return 0;
+}
static inline int pud_clear_huge(pud_t *pud)
{
return 0;
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 48c76d612d40..1b45ac594b54 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -116,7 +116,7 @@ struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
pud_t *pud, int flags);
int pmd_huge(pmd_t pmd);
-int pud_huge(pud_t pmd);
+int pud_huge(pud_t pud);
unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
unsigned long address, unsigned long end, pgprot_t newprot);

@@ -189,6 +189,9 @@ static inline void __unmap_hugepage_range(struct mmu_gather *tlb,
#ifndef pgd_huge
#define pgd_huge(x) 0
#endif
+#ifndef p4d_huge
+#define p4d_huge(x) 0
+#endif

#ifndef pgd_write
static inline int pgd_write(pgd_t pgd)
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 820c0ad54a01..8e52fe609220 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -19,6 +19,7 @@ extern unsigned char kasan_zero_page[PAGE_SIZE];
extern pte_t kasan_zero_pte[PTRS_PER_PTE];
extern pmd_t kasan_zero_pmd[PTRS_PER_PMD];
extern pud_t kasan_zero_pud[PTRS_PER_PUD];
+extern p4d_t kasan_zero_p4d[PTRS_PER_P4D];

void kasan_populate_zero_shadow(const void *shadow_start,
const void *shadow_end);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 58fab8917bbe..9c0ef57e5f56 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1515,14 +1515,24 @@ static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
return ptep;
}

+#ifdef __PAGETABLE_P4D_FOLDED
+static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
+ unsigned long address)
+{
+ return 0;
+}
+#else
+int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
+#endif
+
#ifdef __PAGETABLE_PUD_FOLDED
-static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
+static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d,
unsigned long address)
{
return 0;
}
#else
-int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
+int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address);
#endif

#if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
@@ -1576,10 +1586,18 @@ int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);
#if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)

#ifndef __ARCH_HAS_5LEVEL_HACK
-static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
+static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
+ unsigned long address)
+{
+ return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ?
+ NULL : p4d_offset(pgd, address);
+}
+
+static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
+ unsigned long address)
{
- return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
- NULL: pud_offset(pgd, address);
+ return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ?
+ NULL : pud_offset(p4d, address);
}
#endif /* !__ARCH_HAS_5LEVEL_HACK */

@@ -2318,7 +2336,8 @@ void sparse_mem_maps_populate_node(struct page **map_map,

struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
-pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);
+p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
+pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
void *vmemmap_alloc_block(unsigned long size, int node);
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 86c8911b0e3a..5629eeaba5ae 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -14,6 +14,7 @@
#include <asm/pgtable.h>

#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+static int __read_mostly ioremap_p4d_capable;
static int __read_mostly ioremap_pud_capable;
static int __read_mostly ioremap_pmd_capable;
static int __read_mostly ioremap_huge_disabled;
@@ -35,6 +36,11 @@ void __init ioremap_huge_init(void)
}
}

+static inline int ioremap_p4d_enabled(void)
+{
+ return ioremap_p4d_capable;
+}
+
static inline int ioremap_pud_enabled(void)
{
return ioremap_pud_capable;
@@ -46,6 +52,7 @@ static inline int ioremap_pmd_enabled(void)
}

#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+static inline int ioremap_p4d_enabled(void) { return 0; }
static inline int ioremap_pud_enabled(void) { return 0; }
static inline int ioremap_pmd_enabled(void) { return 0; }
#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
@@ -94,14 +101,14 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
return 0;
}

-static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
+static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
pud_t *pud;
unsigned long next;

phys_addr -= addr;
- pud = pud_alloc(&init_mm, pgd, addr);
+ pud = pud_alloc(&init_mm, p4d, addr);
if (!pud)
return -ENOMEM;
do {
@@ -120,6 +127,32 @@ static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
return 0;
}

+static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
+ unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
+{
+ p4d_t *p4d;
+ unsigned long next;
+
+ phys_addr -= addr;
+ p4d = p4d_alloc(&init_mm, pgd, addr);
+ if (!p4d)
+ return -ENOMEM;
+ do {
+ next = p4d_addr_end(addr, end);
+
+ if (ioremap_p4d_enabled() &&
+ ((next - addr) == P4D_SIZE) &&
+ IS_ALIGNED(phys_addr + addr, P4D_SIZE)) {
+ if (p4d_set_huge(p4d, phys_addr + addr, prot))
+ continue;
+ }
+
+ if (ioremap_pud_range(p4d, addr, next, phys_addr + addr, prot))
+ return -ENOMEM;
+ } while (p4d++, addr = next, addr != end);
+ return 0;
+}
+
int ioremap_page_range(unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
@@ -135,7 +168,7 @@ int ioremap_page_range(unsigned long addr,
pgd = pgd_offset_k(addr);
do {
next = pgd_addr_end(addr, end);
- err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
+ err = ioremap_p4d_range(pgd, addr, next, phys_addr+addr, prot);
if (err)
break;
} while (pgd++, addr = next, addr != end);
diff --git a/mm/gup.c b/mm/gup.c
index 55315555489d..4660b7ee2088 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -226,6 +226,7 @@ struct page *follow_page_mask(struct vm_area_struct *vma,
unsigned int *page_mask)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
spinlock_t *ptl;
@@ -243,8 +244,13 @@ struct page *follow_page_mask(struct vm_area_struct *vma,
pgd = pgd_offset(mm, address);
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
return no_page_table(vma, flags);
-
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (p4d_none(*p4d))
+ return no_page_table(vma, flags);
+ BUILD_BUG_ON(p4d_huge(*p4d));
+ if (unlikely(p4d_bad(*p4d)))
+ return no_page_table(vma, flags);
+ pud = pud_offset(p4d, address);
if (pud_none(*pud))
return no_page_table(vma, flags);
if (pud_huge(*pud) && vma->vm_flags & VM_HUGETLB) {
@@ -317,6 +323,7 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address,
struct page **page)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -330,7 +337,9 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address,
else
pgd = pgd_offset_gate(mm, address);
BUG_ON(pgd_none(*pgd));
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ BUG_ON(p4d_none(*p4d));
+ pud = pud_offset(p4d, address);
BUG_ON(pud_none(*pud));
pmd = pmd_offset(pud, address);
if (pmd_none(*pmd))
@@ -1392,13 +1401,13 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
return 1;
}

-static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end,
+static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end,
int write, struct page **pages, int *nr)
{
unsigned long next;
pud_t *pudp;

- pudp = pud_offset(&pgd, addr);
+ pudp = pud_offset(&p4d, addr);
do {
pud_t pud = READ_ONCE(*pudp);

@@ -1420,6 +1429,31 @@ static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end,
return 1;
}

+static int gup_p4d_range(pgd_t pgd, unsigned long addr, unsigned long end,
+ int write, struct page **pages, int *nr)
+{
+ unsigned long next;
+ p4d_t *p4dp;
+
+ p4dp = p4d_offset(&pgd, addr);
+ do {
+ p4d_t p4d = READ_ONCE(*p4dp);
+
+ next = p4d_addr_end(addr, end);
+ if (p4d_none(p4d))
+ return 0;
+ BUILD_BUG_ON(p4d_huge(p4d));
+ if (unlikely(is_hugepd(__hugepd(p4d_val(p4d))))) {
+ if (!gup_huge_pd(__hugepd(p4d_val(p4d)), addr,
+ P4D_SHIFT, next, write, pages, nr))
+ return 0;
+ } else if (!gup_p4d_range(p4d, addr, next, write, pages, nr))
+ return 0;
+ } while (p4dp++, addr = next, addr != end);
+
+ return 1;
+}
+
/*
* Like get_user_pages_fast() except it's IRQ-safe in that it won't fall back to
* the regular GUP. It will only return non-negative values.
@@ -1470,7 +1504,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
if (!gup_huge_pd(__hugepd(pgd_val(pgd)), addr,
PGDIR_SHIFT, next, write, pages, &nr))
break;
- } else if (!gup_pud_range(pgd, addr, next, write, pages, &nr))
+ } else if (!gup_p4d_range(pgd, addr, next, write, pages, &nr))
break;
} while (pgdp++, addr = next, addr != end);
local_irq_restore(flags);
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 10eedbf14421..37778ab8de40 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1778,6 +1778,7 @@ void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
bool freeze, struct page *page)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;

@@ -1785,7 +1786,11 @@ void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
if (!pgd_present(*pgd))
return;

- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (!p4d_present(*p4d))
+ return;
+
+ pud = pud_offset(p4d, address);
if (!pud_present(*pud))
return;

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 3edb759c5c7d..2359da2264e7 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4366,7 +4366,8 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
{
pgd_t *pgd = pgd_offset(mm, *addr);
- pud_t *pud = pud_offset(pgd, *addr);
+ p4d_t *p4d = p4d_offset(pgd, *addr);
+ pud_t *pud = pud_offset(p4d, *addr);

BUG_ON(page_count(virt_to_page(ptep)) == 0);
if (page_count(virt_to_page(ptep)) == 1)
@@ -4397,11 +4398,13 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pte_t *pte = NULL;

pgd = pgd_offset(mm, addr);
- pud = pud_alloc(mm, pgd, addr);
+ p4d = p4d_offset(pgd, addr);
+ pud = pud_alloc(mm, p4d, addr);
if (pud) {
if (sz == PUD_SIZE) {
pte = (pte_t *)pud;
@@ -4421,18 +4424,22 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
- pmd_t *pmd = NULL;
+ pmd_t *pmd;

pgd = pgd_offset(mm, addr);
- if (pgd_present(*pgd)) {
- pud = pud_offset(pgd, addr);
- if (pud_present(*pud)) {
- if (pud_huge(*pud))
- return (pte_t *)pud;
- pmd = pmd_offset(pud, addr);
- }
- }
+ if (!pgd_present(*pgd))
+ return NULL;
+ p4d = p4d_offset(pgd, addr);
+ if (!p4d_present(*p4d))
+ return NULL;
+ pud = pud_offset(p4d, addr);
+ if (!pud_present(*pud))
+ return NULL;
+ if (pud_huge(*pud))
+ return (pte_t *)pud;
+ pmd = pmd_offset(pud, addr);
return (pte_t *) pmd;
}

diff --git a/mm/kasan/kasan_init.c b/mm/kasan/kasan_init.c
index 3f9a41cf0ac6..0d4ee78796fc 100644
--- a/mm/kasan/kasan_init.c
+++ b/mm/kasan/kasan_init.c
@@ -29,6 +29,9 @@
*/
unsigned char kasan_zero_page[PAGE_SIZE] __page_aligned_bss;

+#if CONFIG_PGTABLE_LEVELS > 4
+p4d_t kasan_zero_p4d[PTRS_PER_P4D] __page_aligned_bss;
+#endif
#if CONFIG_PGTABLE_LEVELS > 3
pud_t kasan_zero_pud[PTRS_PER_PUD] __page_aligned_bss;
#endif
@@ -81,10 +84,10 @@ static void __init zero_pmd_populate(pud_t *pud, unsigned long addr,
} while (pmd++, addr = next, addr != end);
}

-static void __init zero_pud_populate(pgd_t *pgd, unsigned long addr,
+static void __init zero_pud_populate(p4d_t *p4d, unsigned long addr,
unsigned long end)
{
- pud_t *pud = pud_offset(pgd, addr);
+ pud_t *pud = pud_offset(p4d, addr);
unsigned long next;

do {
@@ -106,6 +109,23 @@ static void __init zero_pud_populate(pgd_t *pgd, unsigned long addr,
} while (pud++, addr = next, addr != end);
}

+static void __init zero_p4d_populate(pgd_t *pgd, unsigned long addr,
+ unsigned long end)
+{
+ p4d_t *p4d = p4d_offset(pgd, addr);
+ unsigned long next;
+
+ do {
+ next = p4d_addr_end(addr, end);
+
+ if (p4d_none(*p4d)) {
+ p4d_populate(&init_mm, p4d,
+ early_alloc(PAGE_SIZE, NUMA_NO_NODE));
+ }
+ zero_pud_populate(p4d, addr, next);
+ } while (p4d++, addr = next, addr != end);
+}
+
/**
* kasan_populate_zero_shadow - populate shadow memory region with
* kasan_zero_page
@@ -124,6 +144,7 @@ void __init kasan_populate_zero_shadow(const void *shadow_start,
next = pgd_addr_end(addr, end);

if (IS_ALIGNED(addr, PGDIR_SIZE) && end - addr >= PGDIR_SIZE) {
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;

@@ -135,8 +156,12 @@ void __init kasan_populate_zero_shadow(const void *shadow_start,
* puds,pmds, so pgd_populate(), pud_populate()
* is noops.
*/
- pgd_populate(&init_mm, pgd, kasan_zero_pud);
- pud = pud_offset(pgd, addr);
+#ifndef __ARCH_HAS_5LEVEL_HACK
+ pgd_populate(&init_mm, pgd, kasan_zero_p4d);
+#endif
+ p4d = p4d_offset(pgd, addr);
+ p4d_populate(&init_mm, p4d, kasan_zero_pud);
+ pud = pud_offset(p4d, addr);
pud_populate(&init_mm, pud, kasan_zero_pmd);
pmd = pmd_offset(pud, addr);
pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
@@ -147,6 +172,6 @@ void __init kasan_populate_zero_shadow(const void *shadow_start,
pgd_populate(&init_mm, pgd,
early_alloc(PAGE_SIZE, NUMA_NO_NODE));
}
- zero_pud_populate(pgd, addr, next);
+ zero_p4d_populate(pgd, addr, next);
} while (pgd++, addr = next, addr != end);
}
diff --git a/mm/memory.c b/mm/memory.c
index 7d23b5050248..267cee723aa1 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -442,7 +442,7 @@ static inline void free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
mm_dec_nr_pmds(tlb->mm);
}

-static inline void free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
+static inline void free_pud_range(struct mmu_gather *tlb, p4d_t *p4d,
unsigned long addr, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
@@ -451,7 +451,7 @@ static inline void free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
unsigned long start;

start = addr;
- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
@@ -459,6 +459,39 @@ static inline void free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
free_pmd_range(tlb, pud, addr, next, floor, ceiling);
} while (pud++, addr = next, addr != end);

+ start &= P4D_MASK;
+ if (start < floor)
+ return;
+ if (ceiling) {
+ ceiling &= P4D_MASK;
+ if (!ceiling)
+ return;
+ }
+ if (end - 1 > ceiling - 1)
+ return;
+
+ pud = pud_offset(p4d, start);
+ p4d_clear(p4d);
+ pud_free_tlb(tlb, pud, start);
+}
+
+static inline void free_p4d_range(struct mmu_gather *tlb, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ unsigned long floor, unsigned long ceiling)
+{
+ p4d_t *p4d;
+ unsigned long next;
+ unsigned long start;
+
+ start = addr;
+ p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none_or_clear_bad(p4d))
+ continue;
+ free_pud_range(tlb, p4d, addr, next, floor, ceiling);
+ } while (p4d++, addr = next, addr != end);
+
start &= PGDIR_MASK;
if (start < floor)
return;
@@ -470,9 +503,9 @@ static inline void free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
if (end - 1 > ceiling - 1)
return;

- pud = pud_offset(pgd, start);
+ p4d = p4d_offset(pgd, start);
pgd_clear(pgd);
- pud_free_tlb(tlb, pud, start);
+ p4d_free_tlb(tlb, p4d, start);
}

/*
@@ -536,7 +569,7 @@ void free_pgd_range(struct mmu_gather *tlb,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- free_pud_range(tlb, pgd, addr, next, floor, ceiling);
+ free_p4d_range(tlb, pgd, addr, next, floor, ceiling);
} while (pgd++, addr = next, addr != end);
}

@@ -655,7 +688,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
pte_t pte, struct page *page)
{
pgd_t *pgd = pgd_offset(vma->vm_mm, addr);
- pud_t *pud = pud_offset(pgd, addr);
+ p4d_t *p4d = p4d_offset(pgd, addr);
+ pud_t *pud = pud_offset(p4d, addr);
pmd_t *pmd = pmd_offset(pud, addr);
struct address_space *mapping;
pgoff_t index;
@@ -1020,16 +1054,16 @@ static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src
}

static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
- pgd_t *dst_pgd, pgd_t *src_pgd, struct vm_area_struct *vma,
+ p4d_t *dst_p4d, p4d_t *src_p4d, struct vm_area_struct *vma,
unsigned long addr, unsigned long end)
{
pud_t *src_pud, *dst_pud;
unsigned long next;

- dst_pud = pud_alloc(dst_mm, dst_pgd, addr);
+ dst_pud = pud_alloc(dst_mm, dst_p4d, addr);
if (!dst_pud)
return -ENOMEM;
- src_pud = pud_offset(src_pgd, addr);
+ src_pud = pud_offset(src_p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(src_pud))
@@ -1041,6 +1075,28 @@ static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src
return 0;
}

+static inline int copy_p4d_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
+ pgd_t *dst_pgd, pgd_t *src_pgd, struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end)
+{
+ p4d_t *src_p4d, *dst_p4d;
+ unsigned long next;
+
+ dst_p4d = p4d_alloc(dst_mm, dst_pgd, addr);
+ if (!dst_p4d)
+ return -ENOMEM;
+ src_p4d = p4d_offset(src_pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none_or_clear_bad(src_p4d))
+ continue;
+ if (copy_pud_range(dst_mm, src_mm, dst_p4d, src_p4d,
+ vma, addr, next))
+ return -ENOMEM;
+ } while (dst_p4d++, src_p4d++, addr = next, addr != end);
+ return 0;
+}
+
int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
struct vm_area_struct *vma)
{
@@ -1096,7 +1152,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(src_pgd))
continue;
- if (unlikely(copy_pud_range(dst_mm, src_mm, dst_pgd, src_pgd,
+ if (unlikely(copy_p4d_range(dst_mm, src_mm, dst_pgd, src_pgd,
vma, addr, next))) {
ret = -ENOMEM;
break;
@@ -1259,14 +1315,14 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb,
}

static inline unsigned long zap_pud_range(struct mmu_gather *tlb,
- struct vm_area_struct *vma, pgd_t *pgd,
+ struct vm_area_struct *vma, p4d_t *p4d,
unsigned long addr, unsigned long end,
struct zap_details *details)
{
pud_t *pud;
unsigned long next;

- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
@@ -1277,6 +1333,25 @@ static inline unsigned long zap_pud_range(struct mmu_gather *tlb,
return addr;
}

+static inline unsigned long zap_p4d_range(struct mmu_gather *tlb,
+ struct vm_area_struct *vma, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ struct zap_details *details)
+{
+ p4d_t *p4d;
+ unsigned long next;
+
+ p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none_or_clear_bad(p4d))
+ continue;
+ next = zap_pud_range(tlb, vma, p4d, addr, next, details);
+ } while (p4d++, addr = next, addr != end);
+
+ return addr;
+}
+
void unmap_page_range(struct mmu_gather *tlb,
struct vm_area_struct *vma,
unsigned long addr, unsigned long end,
@@ -1292,7 +1367,7 @@ void unmap_page_range(struct mmu_gather *tlb,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- next = zap_pud_range(tlb, vma, pgd, addr, next, details);
+ next = zap_p4d_range(tlb, vma, pgd, addr, next, details);
} while (pgd++, addr = next, addr != end);
tlb_end_vma(tlb, vma);
}
@@ -1448,16 +1523,24 @@ EXPORT_SYMBOL_GPL(zap_vma_ptes);
pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
spinlock_t **ptl)
{
- pgd_t * pgd = pgd_offset(mm, addr);
- pud_t * pud = pud_alloc(mm, pgd, addr);
- if (pud) {
- pmd_t * pmd = pmd_alloc(mm, pud, addr);
- if (pmd) {
- VM_BUG_ON(pmd_trans_huge(*pmd));
- return pte_alloc_map_lock(mm, pmd, addr, ptl);
- }
- }
- return NULL;
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ pgd = pgd_offset(mm, addr);
+ p4d = p4d_alloc(mm, pgd, addr);
+ if (!p4d)
+ return NULL;
+ pud = pud_alloc(mm, p4d, addr);
+ if (!pud)
+ return NULL;
+ pmd = pmd_alloc(mm, pud, addr);
+ if (!pmd)
+ return NULL;
+
+ VM_BUG_ON(pmd_trans_huge(*pmd));
+ return pte_alloc_map_lock(mm, pmd, addr, ptl);
}

/*
@@ -1723,7 +1806,7 @@ static inline int remap_pmd_range(struct mm_struct *mm, pud_t *pud,
return 0;
}

-static inline int remap_pud_range(struct mm_struct *mm, pgd_t *pgd,
+static inline int remap_pud_range(struct mm_struct *mm, p4d_t *p4d,
unsigned long addr, unsigned long end,
unsigned long pfn, pgprot_t prot)
{
@@ -1731,7 +1814,7 @@ static inline int remap_pud_range(struct mm_struct *mm, pgd_t *pgd,
unsigned long next;

pfn -= addr >> PAGE_SHIFT;
- pud = pud_alloc(mm, pgd, addr);
+ pud = pud_alloc(mm, p4d, addr);
if (!pud)
return -ENOMEM;
do {
@@ -1743,6 +1826,26 @@ static inline int remap_pud_range(struct mm_struct *mm, pgd_t *pgd,
return 0;
}

+static inline int remap_p4d_range(struct mm_struct *mm, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ unsigned long pfn, pgprot_t prot)
+{
+ p4d_t *p4d;
+ unsigned long next;
+
+ pfn -= addr >> PAGE_SHIFT;
+ p4d = p4d_alloc(mm, pgd, addr);
+ if (!p4d)
+ return -ENOMEM;
+ do {
+ next = p4d_addr_end(addr, end);
+ if (remap_pud_range(mm, p4d, addr, next,
+ pfn + (addr >> PAGE_SHIFT), prot))
+ return -ENOMEM;
+ } while (p4d++, addr = next, addr != end);
+ return 0;
+}
+
/**
* remap_pfn_range - remap kernel memory to userspace
* @vma: user vma to map to
@@ -1799,7 +1902,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
flush_cache_range(vma, addr, end);
do {
next = pgd_addr_end(addr, end);
- err = remap_pud_range(mm, pgd, addr, next,
+ err = remap_p4d_range(mm, pgd, addr, next,
pfn + (addr >> PAGE_SHIFT), prot);
if (err)
break;
@@ -1915,7 +2018,7 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud,
return err;
}

-static int apply_to_pud_range(struct mm_struct *mm, pgd_t *pgd,
+static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d,
unsigned long addr, unsigned long end,
pte_fn_t fn, void *data)
{
@@ -1923,7 +2026,7 @@ static int apply_to_pud_range(struct mm_struct *mm, pgd_t *pgd,
unsigned long next;
int err;

- pud = pud_alloc(mm, pgd, addr);
+ pud = pud_alloc(mm, p4d, addr);
if (!pud)
return -ENOMEM;
do {
@@ -1935,6 +2038,26 @@ static int apply_to_pud_range(struct mm_struct *mm, pgd_t *pgd,
return err;
}

+static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ pte_fn_t fn, void *data)
+{
+ p4d_t *p4d;
+ unsigned long next;
+ int err;
+
+ p4d = p4d_alloc(mm, pgd, addr);
+ if (!p4d)
+ return -ENOMEM;
+ do {
+ next = p4d_addr_end(addr, end);
+ err = apply_to_pud_range(mm, p4d, addr, next, fn, data);
+ if (err)
+ break;
+ } while (p4d++, addr = next, addr != end);
+ return err;
+}
+
/*
* Scan a region of virtual memory, filling in page tables as necessary
* and calling a provided function on each leaf page table.
@@ -1953,7 +2076,7 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
pgd = pgd_offset(mm, addr);
do {
next = pgd_addr_end(addr, end);
- err = apply_to_pud_range(mm, pgd, addr, next, fn, data);
+ err = apply_to_p4d_range(mm, pgd, addr, next, fn, data);
if (err)
break;
} while (pgd++, addr = next, addr != end);
@@ -3622,10 +3745,14 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
};
struct mm_struct *mm = vma->vm_mm;
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;

pgd = pgd_offset(mm, address);
- pud = pud_alloc(mm, pgd, address);
+ p4d = p4d_alloc(mm, pgd, address);
+ if (!p4d)
+ return VM_FAULT_OOM;
+ pud = pud_alloc(mm, p4d, address);
if (!pud)
return VM_FAULT_OOM;
vmf.pmd = pmd_alloc(mm, pud, address);
@@ -3729,7 +3856,7 @@ EXPORT_SYMBOL_GPL(handle_mm_fault);
* Allocate page upper directory.
* We've already handled the fast-path in-line.
*/
-int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
+int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address)
{
pud_t *new = pud_alloc_one(mm, address);
if (!new)
@@ -3738,10 +3865,17 @@ int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
smp_wmb(); /* See comment in __pte_alloc */

spin_lock(&mm->page_table_lock);
- if (pgd_present(*pgd)) /* Another has populated it */
+#ifndef __ARCH_HAS_5LEVEL_HACK
+ if (p4d_present(*p4d)) /* Another has populated it */
+ pud_free(mm, new);
+ else
+ p4d_populate(mm, p4d, new);
+#else
+ if (pgd_present(*p4d)) /* Another has populated it */
pud_free(mm, new);
else
- pgd_populate(mm, pgd, new);
+ pgd_populate(mm, p4d, new);
+#endif /* __ARCH_HAS_5LEVEL_HACK */
spin_unlock(&mm->page_table_lock);
return 0;
}
@@ -3783,6 +3917,7 @@ static int __follow_pte(struct mm_struct *mm, unsigned long address,
pte_t **ptepp, spinlock_t **ptlp)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *ptep;
@@ -3791,7 +3926,11 @@ static int __follow_pte(struct mm_struct *mm, unsigned long address,
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
goto out;

- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (p4d_none(*p4d) || unlikely(p4d_bad(*p4d)))
+ goto out;
+
+ pud = pud_offset(p4d, address);
if (pud_none(*pud) || unlikely(pud_bad(*pud)))
goto out;

diff --git a/mm/mlock.c b/mm/mlock.c
index cdbed8aaa426..81fe0c18e29d 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -379,6 +379,7 @@ static unsigned long __munlock_pagevec_fill(struct pagevec *pvec,
pte = get_locked_pte(vma->vm_mm, start, &ptl);
/* Make sure we do not cross the page table boundary */
end = pgd_addr_end(start, end);
+ end = p4d_addr_end(start, end);
end = pud_addr_end(start, end);
end = pmd_addr_end(start, end);

diff --git a/mm/mprotect.c b/mm/mprotect.c
index f9c07f54dd62..af677fe954bc 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -209,14 +209,14 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
}

static inline unsigned long change_pud_range(struct vm_area_struct *vma,
- pgd_t *pgd, unsigned long addr, unsigned long end,
+ p4d_t *p4d, unsigned long addr, unsigned long end,
pgprot_t newprot, int dirty_accountable, int prot_numa)
{
pud_t *pud;
unsigned long next;
unsigned long pages = 0;

- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
@@ -228,6 +228,26 @@ static inline unsigned long change_pud_range(struct vm_area_struct *vma,
return pages;
}

+static inline unsigned long change_p4d_range(struct vm_area_struct *vma,
+ pgd_t *pgd, unsigned long addr, unsigned long end,
+ pgprot_t newprot, int dirty_accountable, int prot_numa)
+{
+ p4d_t *p4d;
+ unsigned long next;
+ unsigned long pages = 0;
+
+ p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none_or_clear_bad(p4d))
+ continue;
+ pages += change_pud_range(vma, p4d, addr, next, newprot,
+ dirty_accountable, prot_numa);
+ } while (p4d++, addr = next, addr != end);
+
+ return pages;
+}
+
static unsigned long change_protection_range(struct vm_area_struct *vma,
unsigned long addr, unsigned long end, pgprot_t newprot,
int dirty_accountable, int prot_numa)
@@ -246,7 +266,7 @@ static unsigned long change_protection_range(struct vm_area_struct *vma,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- pages += change_pud_range(vma, pgd, addr, next, newprot,
+ pages += change_p4d_range(vma, pgd, addr, next, newprot,
dirty_accountable, prot_numa);
} while (pgd++, addr = next, addr != end);

diff --git a/mm/mremap.c b/mm/mremap.c
index 30d7d2482eea..2b3bfcd51c75 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -31,6 +31,7 @@
static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;

@@ -38,7 +39,11 @@ static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr)
if (pgd_none_or_clear_bad(pgd))
return NULL;

- pud = pud_offset(pgd, addr);
+ p4d = p4d_offset(pgd, addr);
+ if (p4d_none_or_clear_bad(p4d))
+ return NULL;
+
+ pud = pud_offset(p4d, addr);
if (pud_none_or_clear_bad(pud))
return NULL;

@@ -53,11 +58,15 @@ static pmd_t *alloc_new_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;

pgd = pgd_offset(mm, addr);
- pud = pud_alloc(mm, pgd, addr);
+ p4d = p4d_alloc(mm, pgd, addr);
+ if (!p4d)
+ return NULL;
+ pud = pud_alloc(mm, p4d, addr);
if (!pud)
return NULL;

diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index 207244489a68..0020f340abfd 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -69,14 +69,14 @@ static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
return err;
}

-static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end,
+static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
pud_t *pud;
unsigned long next;
int err = 0;

- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud)) {
@@ -95,6 +95,32 @@ static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end,
return err;
}

+static int walk_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ p4d_t *p4d;
+ unsigned long next;
+ int err = 0;
+
+ p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none_or_clear_bad(p4d)) {
+ if (walk->pte_hole)
+ err = walk->pte_hole(addr, next, walk);
+ if (err)
+ break;
+ continue;
+ }
+ if (walk->pmd_entry || walk->pte_entry)
+ err = walk_pud_range(p4d, addr, next, walk);
+ if (err)
+ break;
+ } while (p4d++, addr = next, addr != end);
+
+ return err;
+}
+
static int walk_pgd_range(unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
@@ -113,7 +139,7 @@ static int walk_pgd_range(unsigned long addr, unsigned long end,
continue;
}
if (walk->pmd_entry || walk->pte_entry)
- err = walk_pud_range(pgd, addr, next, walk);
+ err = walk_p4d_range(pgd, addr, next, walk);
if (err)
break;
} while (pgd++, addr = next, addr != end);
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 71c5f9109f2a..738e278b48c1 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -22,6 +22,12 @@ void pgd_clear_bad(pgd_t *pgd)
pgd_clear(pgd);
}

+void p4d_clear_bad(p4d_t *p4d)
+{
+ p4d_ERROR(*p4d);
+ p4d_clear(p4d);
+}
+
void pud_clear_bad(pud_t *pud)
{
pud_ERROR(*pud);
diff --git a/mm/rmap.c b/mm/rmap.c
index 91619fd70939..257cb67892ee 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -684,6 +684,7 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd = NULL;
pmd_t pmde;
@@ -692,7 +693,11 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
if (!pgd_present(*pgd))
goto out;

- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (!p4d_present(*p4d))
+ goto out;
+
+ pud = pud_offset(p4d, address);
if (!pud_present(*pud))
goto out;

@@ -797,6 +802,7 @@ bool page_check_address_transhuge(struct page *page, struct mm_struct *mm,
pte_t **ptep, spinlock_t **ptlp)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -816,7 +822,10 @@ bool page_check_address_transhuge(struct page *page, struct mm_struct *mm,
pgd = pgd_offset(mm, address);
if (!pgd_present(*pgd))
return false;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (!p4d_present(*p4d))
+ return false;
+ pud = pud_offset(p4d, address);
if (!pud_present(*pud))
return false;
pmd = pmd_offset(pud, address);
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 574c67b663fe..a56c3989f773 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -196,9 +196,9 @@ pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
return pmd;
}

-pud_t * __meminit vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node)
+pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
{
- pud_t *pud = pud_offset(pgd, addr);
+ pud_t *pud = pud_offset(p4d, addr);
if (pud_none(*pud)) {
void *p = vmemmap_alloc_block(PAGE_SIZE, node);
if (!p)
@@ -208,6 +208,18 @@ pud_t * __meminit vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node)
return pud;
}

+p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
+{
+ p4d_t *p4d = p4d_offset(pgd, addr);
+ if (p4d_none(*p4d)) {
+ void *p = vmemmap_alloc_block(PAGE_SIZE, node);
+ if (!p)
+ return NULL;
+ p4d_populate(&init_mm, p4d, p);
+ }
+ return p4d;
+}
+
pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
{
pgd_t *pgd = pgd_offset_k(addr);
@@ -225,6 +237,7 @@ int __meminit vmemmap_populate_basepages(unsigned long start,
{
unsigned long addr = start;
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -233,7 +246,10 @@ int __meminit vmemmap_populate_basepages(unsigned long start,
pgd = vmemmap_pgd_populate(addr, node);
if (!pgd)
return -ENOMEM;
- pud = vmemmap_pud_populate(pgd, addr, node);
+ p4d = vmemmap_p4d_populate(pgd, addr, node);
+ if (!p4d)
+ return -ENOMEM;
+ pud = vmemmap_pud_populate(p4d, addr, node);
if (!pud)
return -ENOMEM;
pmd = vmemmap_pmd_populate(pud, addr, node);
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 1c6e0321205d..0d3bd27dba69 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1245,7 +1245,7 @@ static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud,
return 0;
}

-static inline int unuse_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+static inline int unuse_pud_range(struct vm_area_struct *vma, p4d_t *p4d,
unsigned long addr, unsigned long end,
swp_entry_t entry, struct page *page)
{
@@ -1253,7 +1253,7 @@ static inline int unuse_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
unsigned long next;
int ret;

- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
@@ -1265,6 +1265,26 @@ static inline int unuse_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
return 0;
}

+static inline int unuse_p4d_range(struct vm_area_struct *vma, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ swp_entry_t entry, struct page *page)
+{
+ p4d_t *p4d;
+ unsigned long next;
+ int ret;
+
+ p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none_or_clear_bad(p4d))
+ continue;
+ ret = unuse_pud_range(vma, p4d, addr, next, entry, page);
+ if (ret)
+ return ret;
+ } while (p4d++, addr = next, addr != end);
+ return 0;
+}
+
static int unuse_vma(struct vm_area_struct *vma,
swp_entry_t entry, struct page *page)
{
@@ -1288,7 +1308,7 @@ static int unuse_vma(struct vm_area_struct *vma,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- ret = unuse_pud_range(vma, pgd, addr, next, entry, page);
+ ret = unuse_p4d_range(vma, pgd, addr, next, entry, page);
if (ret)
return ret;
} while (pgd++, addr = next, addr != end);
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index af817e5060fb..721681deba9f 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -124,19 +124,22 @@ static int mfill_zeropage_pte(struct mm_struct *dst_mm,
static pmd_t *mm_alloc_pmd(struct mm_struct *mm, unsigned long address)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
- pmd_t *pmd = NULL;

pgd = pgd_offset(mm, address);
- pud = pud_alloc(mm, pgd, address);
- if (pud)
- /*
- * Note that we didn't run this because the pmd was
- * missing, the *pmd may be already established and in
- * turn it may also be a trans_huge_pmd.
- */
- pmd = pmd_alloc(mm, pud, address);
- return pmd;
+ p4d = p4d_alloc(mm, pgd, address);
+ if (!p4d)
+ return NULL;
+ pud = pud_alloc(mm, p4d, address);
+ if (!pud)
+ return NULL;
+ /*
+ * Note that we didn't run this because the pmd was
+ * missing, the *pmd may be already established and in
+ * turn it may also be a trans_huge_pmd.
+ */
+ return pmd_alloc(mm, pud, address);
}

static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm,
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 3ca82d44edd3..35ff0d0e6400 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -86,12 +86,12 @@ static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end)
} while (pmd++, addr = next, addr != end);
}

-static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end)
+static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end)
{
pud_t *pud;
unsigned long next;

- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (pud_clear_huge(pud))
@@ -102,6 +102,22 @@ static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end)
} while (pud++, addr = next, addr != end);
}

+static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end)
+{
+ p4d_t *p4d;
+ unsigned long next;
+
+ p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_clear_huge(p4d))
+ continue;
+ if (p4d_none_or_clear_bad(p4d))
+ continue;
+ vunmap_pud_range(p4d, addr, next);
+ } while (p4d++, addr = next, addr != end);
+}
+
static void vunmap_page_range(unsigned long addr, unsigned long end)
{
pgd_t *pgd;
@@ -113,7 +129,7 @@ static void vunmap_page_range(unsigned long addr, unsigned long end)
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- vunmap_pud_range(pgd, addr, next);
+ vunmap_p4d_range(pgd, addr, next);
} while (pgd++, addr = next, addr != end);
}

@@ -160,13 +176,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr,
return 0;
}

-static int vmap_pud_range(pgd_t *pgd, unsigned long addr,
+static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
unsigned long end, pgprot_t prot, struct page **pages, int *nr)
{
pud_t *pud;
unsigned long next;

- pud = pud_alloc(&init_mm, pgd, addr);
+ pud = pud_alloc(&init_mm, p4d, addr);
if (!pud)
return -ENOMEM;
do {
@@ -177,6 +193,23 @@ static int vmap_pud_range(pgd_t *pgd, unsigned long addr,
return 0;
}

+static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
+ unsigned long end, pgprot_t prot, struct page **pages, int *nr)
+{
+ p4d_t *p4d;
+ unsigned long next;
+
+ p4d = p4d_alloc(&init_mm, pgd, addr);
+ if (!p4d)
+ return -ENOMEM;
+ do {
+ next = p4d_addr_end(addr, end);
+ if (vmap_pud_range(p4d, addr, next, prot, pages, nr))
+ return -ENOMEM;
+ } while (p4d++, addr = next, addr != end);
+ return 0;
+}
+
/*
* Set up page tables in kva (addr, end). The ptes shall have prot "prot", and
* will have pfns corresponding to the "pages" array.
@@ -196,7 +229,7 @@ static int vmap_page_range_noflush(unsigned long start, unsigned long end,
pgd = pgd_offset_k(addr);
do {
next = pgd_addr_end(addr, end);
- err = vmap_pud_range(pgd, addr, next, prot, pages, &nr);
+ err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr);
if (err)
return err;
} while (pgd++, addr = next, addr != end);
@@ -237,6 +270,10 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
unsigned long addr = (unsigned long) vmalloc_addr;
struct page *page = NULL;
pgd_t *pgd = pgd_offset_k(addr);
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *ptep, pte;

/*
* XXX we might need to change this if we add VIRTUAL_BUG_ON for
@@ -244,21 +281,23 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
*/
VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));

- if (!pgd_none(*pgd)) {
- pud_t *pud = pud_offset(pgd, addr);
- if (!pud_none(*pud)) {
- pmd_t *pmd = pmd_offset(pud, addr);
- if (!pmd_none(*pmd)) {
- pte_t *ptep, pte;
-
- ptep = pte_offset_map(pmd, addr);
- pte = *ptep;
- if (pte_present(pte))
- page = pte_page(pte);
- pte_unmap(ptep);
- }
- }
- }
+ if (pgd_none(*pgd))
+ return NULL;
+ p4d = p4d_offset(pgd, addr);
+ if (p4d_none(*p4d))
+ return NULL;
+ pud = pud_offset(p4d, addr);
+ if (pud_none(*pud))
+ return NULL;
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd))
+ return NULL;
+
+ ptep = pte_offset_map(pmd, addr);
+ pte = *ptep;
+ if (pte_present(pte))
+ page = pte_page(pte);
+ pte_unmap(ptep);
return page;
}
EXPORT_SYMBOL(vmalloc_to_page);
--
2.11.0