[PATCH v4 03/14] arm64: add support for folded p4d page tables

From: Mike Rapoport
Date: Tue Apr 14 2020 - 11:37:03 EST

From: Mike Rapoport <rppt@xxxxxxxxxxxxx>

Implement primitives necessary for the 4th level folding, add walks of p4d
level where appropriate, replace 5level-fixup.h with pgtable-nop4d.h and
remove __ARCH_USE_5LEVEL_HACK.

Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
---
arch/arm64/include/asm/kvm_mmu.h | 10 +-
arch/arm64/include/asm/pgalloc.h | 10 +-
arch/arm64/include/asm/pgtable-types.h | 5 +-
arch/arm64/include/asm/pgtable.h | 37 +++--
arch/arm64/include/asm/stage2_pgtable.h | 48 ++++--
arch/arm64/kernel/hibernate.c | 44 ++++-
arch/arm64/mm/fault.c | 9 +-
arch/arm64/mm/hugetlbpage.c | 15 +-
arch/arm64/mm/kasan_init.c | 26 ++-
arch/arm64/mm/mmu.c | 52 ++++--
arch/arm64/mm/pageattr.c | 7 +-
virt/kvm/arm/mmu.c | 209 ++++++++++++++++++++----
12 files changed, 368 insertions(+), 104 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 30b0e8d6b895..8255fab2e441 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -172,8 +172,8 @@ void kvm_clear_hyp_idmap(void);
__pmd(__phys_to_pmd_val(__pa(ptep)) | PMD_TYPE_TABLE)
#define kvm_mk_pud(pmdp) \
__pud(__phys_to_pud_val(__pa(pmdp)) | PMD_TYPE_TABLE)
-#define kvm_mk_pgd(pudp) \
- __pgd(__phys_to_pgd_val(__pa(pudp)) | PUD_TYPE_TABLE)
+#define kvm_mk_p4d(pmdp) \
+ __p4d(__phys_to_p4d_val(__pa(pmdp)) | PUD_TYPE_TABLE)

#define kvm_set_pud(pudp, pud) set_pud(pudp, pud)

@@ -299,6 +299,12 @@ static inline bool kvm_s2pud_young(pud_t pud)
#define hyp_pud_table_empty(pudp) kvm_page_empty(pudp)
#endif

+#ifdef __PAGETABLE_P4D_FOLDED
+#define hyp_p4d_table_empty(p4dp) (0)
+#else
+#define hyp_p4d_table_empty(p4dp) kvm_page_empty(p4dp)
+#endif
+
struct kvm;

#define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l))
diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
index 172d76fa0245..58e93583ddb6 100644
--- a/arch/arm64/include/asm/pgalloc.h
+++ b/arch/arm64/include/asm/pgalloc.h
@@ -73,17 +73,17 @@ static inline void pud_free(struct mm_struct *mm, pud_t *pudp)
free_page((unsigned long)pudp);
}

-static inline void __pgd_populate(pgd_t *pgdp, phys_addr_t pudp, pgdval_t prot)
+static inline void __p4d_populate(p4d_t *p4dp, phys_addr_t pudp, p4dval_t prot)
{
- set_pgd(pgdp, __pgd(__phys_to_pgd_val(pudp) | prot));
+ set_p4d(p4dp, __p4d(__phys_to_p4d_val(pudp) | prot));
}

-static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgdp, pud_t *pudp)
+static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp)
{
- __pgd_populate(pgdp, __pa(pudp), PUD_TYPE_TABLE);
+ __p4d_populate(p4dp, __pa(pudp), PUD_TYPE_TABLE);
}
#else
-static inline void __pgd_populate(pgd_t *pgdp, phys_addr_t pudp, pgdval_t prot)
+static inline void __p4d_populate(p4d_t *p4dp, phys_addr_t pudp, p4dval_t prot)
{
BUILD_BUG();
}
diff --git a/arch/arm64/include/asm/pgtable-types.h b/arch/arm64/include/asm/pgtable-types.h
index acb0751a6606..b8f158ae2527 100644
--- a/arch/arm64/include/asm/pgtable-types.h
+++ b/arch/arm64/include/asm/pgtable-types.h
@@ -14,6 +14,7 @@
typedef u64 pteval_t;
typedef u64 pmdval_t;
typedef u64 pudval_t;
+typedef u64 p4dval_t;
typedef u64 pgdval_t;

/*
@@ -44,13 +45,11 @@ typedef struct { pteval_t pgprot; } pgprot_t;
#define __pgprot(x) ((pgprot_t) { (x) } )

#if CONFIG_PGTABLE_LEVELS == 2
-#define __ARCH_USE_5LEVEL_HACK
#include <asm-generic/pgtable-nopmd.h>
#elif CONFIG_PGTABLE_LEVELS == 3
-#define __ARCH_USE_5LEVEL_HACK
#include <asm-generic/pgtable-nopud.h>
#elif CONFIG_PGTABLE_LEVELS == 4
-#include <asm-generic/5level-fixup.h>
+#include <asm-generic/pgtable-nop4d.h>
#endif

#endif /* __ASM_PGTABLE_TYPES_H */
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 538c85e62f86..c23c5a4e6dc6 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -298,6 +298,11 @@ static inline pte_t pgd_pte(pgd_t pgd)
return __pte(pgd_val(pgd));
}

+static inline pte_t p4d_pte(p4d_t p4d)
+{
+ return __pte(p4d_val(p4d));
+}
+
static inline pte_t pud_pte(pud_t pud)
{
return __pte(pud_val(pud));
@@ -401,6 +406,9 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd)

#define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))

+#define __p4d_to_phys(p4d) __pte_to_phys(p4d_pte(p4d))
+#define __phys_to_p4d_val(phys) __phys_to_pte_val(phys)
+
#define __pgd_to_phys(pgd) __pte_to_phys(pgd_pte(pgd))
#define __phys_to_pgd_val(phys) __phys_to_pte_val(phys)

@@ -588,49 +596,50 @@ static inline phys_addr_t pud_page_paddr(pud_t pud)

#define pud_ERROR(pud) __pud_error(__FILE__, __LINE__, pud_val(pud))

-#define pgd_none(pgd) (!pgd_val(pgd))
-#define pgd_bad(pgd) (!(pgd_val(pgd) & 2))
-#define pgd_present(pgd) (pgd_val(pgd))
+#define p4d_none(p4d) (!p4d_val(p4d))
+#define p4d_bad(p4d) (!(p4d_val(p4d) & 2))
+#define p4d_present(p4d) (p4d_val(p4d))

-static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
+static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
{
- if (in_swapper_pgdir(pgdp)) {
- set_swapper_pgd(pgdp, pgd);
+ if (in_swapper_pgdir(p4dp)) {
+ set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
return;
}

- WRITE_ONCE(*pgdp, pgd);
+ WRITE_ONCE(*p4dp, p4d);
dsb(ishst);
isb();
}

-static inline void pgd_clear(pgd_t *pgdp)
+static inline void p4d_clear(p4d_t *p4dp)
{
- set_pgd(pgdp, __pgd(0));
+ set_p4d(p4dp, __p4d(0));
}

-static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
+static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
{
- return __pgd_to_phys(pgd);
+ return __p4d_to_phys(p4d);
}

/* Find an entry in the frst-level page table. */
#define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))

-#define pud_offset_phys(dir, addr) (pgd_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t))
+#define pud_offset_phys(dir, addr) (p4d_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t))
#define pud_offset(dir, addr) ((pud_t *)__va(pud_offset_phys((dir), (addr))))

#define pud_set_fixmap(addr) ((pud_t *)set_fixmap_offset(FIX_PUD, addr))
-#define pud_set_fixmap_offset(pgd, addr) pud_set_fixmap(pud_offset_phys(pgd, addr))
+#define pud_set_fixmap_offset(p4d, addr) pud_set_fixmap(pud_offset_phys(p4d, addr))
#define pud_clear_fixmap() clear_fixmap(FIX_PUD)

-#define pgd_page(pgd) pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
+#define p4d_page(p4d) pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))

/* use ONLY for statically allocated translation tables */
#define pud_offset_kimg(dir,addr) ((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr))))

#else

+#define p4d_page_paddr(p4d) ({ BUILD_BUG(); 0;})
#define pgd_page_paddr(pgd) ({ BUILD_BUG(); 0;})

/* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h
index 326aac658b9d..9a364aeae5fb 100644
--- a/arch/arm64/include/asm/stage2_pgtable.h
+++ b/arch/arm64/include/asm/stage2_pgtable.h
@@ -68,41 +68,67 @@ static inline bool kvm_stage2_has_pud(struct kvm *kvm)
#define S2_PUD_SIZE (1UL << S2_PUD_SHIFT)
#define S2_PUD_MASK (~(S2_PUD_SIZE - 1))

-static inline bool stage2_pgd_none(struct kvm *kvm, pgd_t pgd)
+#define stage2_pgd_none(kvm, pgd) pgd_none(pgd)
+#define stage2_pgd_clear(kvm, pgd) pgd_clear(pgd)
+#define stage2_pgd_present(kvm, pgd) pgd_present(pgd)
+#define stage2_pgd_populate(kvm, pgd, p4d) pgd_populate(NULL, pgd, p4d)
+
+static inline p4d_t *stage2_p4d_offset(struct kvm *kvm,
+ pgd_t *pgd, unsigned long address)
+{
+ return p4d_offset(pgd, address);
+}
+
+static inline void stage2_p4d_free(struct kvm *kvm, p4d_t *p4d)
+{
+}
+
+static inline bool stage2_p4d_table_empty(struct kvm *kvm, p4d_t *p4dp)
+{
+ return false;
+}
+
+static inline phys_addr_t stage2_p4d_addr_end(struct kvm *kvm,
+ phys_addr_t addr, phys_addr_t end)
+{
+ return end;
+}
+
+static inline bool stage2_p4d_none(struct kvm *kvm, p4d_t p4d)
{
if (kvm_stage2_has_pud(kvm))
- return pgd_none(pgd);
+ return p4d_none(p4d);
else
return 0;
}

-static inline void stage2_pgd_clear(struct kvm *kvm, pgd_t *pgdp)
+static inline void stage2_p4d_clear(struct kvm *kvm, p4d_t *p4dp)
{
if (kvm_stage2_has_pud(kvm))
- pgd_clear(pgdp);
+ p4d_clear(p4dp);
}

-static inline bool stage2_pgd_present(struct kvm *kvm, pgd_t pgd)
+static inline bool stage2_p4d_present(struct kvm *kvm, p4d_t p4d)
{
if (kvm_stage2_has_pud(kvm))
- return pgd_present(pgd);
+ return p4d_present(p4d);
else
return 1;
}

-static inline void stage2_pgd_populate(struct kvm *kvm, pgd_t *pgd, pud_t *pud)
+static inline void stage2_p4d_populate(struct kvm *kvm, p4d_t *p4d, pud_t *pud)
{
if (kvm_stage2_has_pud(kvm))
- pgd_populate(NULL, pgd, pud);
+ p4d_populate(NULL, p4d, pud);
}

static inline pud_t *stage2_pud_offset(struct kvm *kvm,
- pgd_t *pgd, unsigned long address)
+ p4d_t *p4d, unsigned long address)
{
if (kvm_stage2_has_pud(kvm))
- return pud_offset(pgd, address);
+ return pud_offset(p4d, address);
else
- return (pud_t *)pgd;
+ return (pud_t *)p4d;
}

static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud)
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 5b73e92c99e3..a8a4b55f3a09 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -184,6 +184,7 @@ static int trans_pgd_map_page(pgd_t *trans_pgd, void *page,
pgprot_t pgprot)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
@@ -196,7 +197,15 @@ static int trans_pgd_map_page(pgd_t *trans_pgd, void *page,
pgd_populate(&init_mm, pgdp, pudp);
}

- pudp = pud_offset(pgdp, dst_addr);
+ p4dp = p4d_offset(pgdp, dst_addr);
+ if (p4d_none(READ_ONCE(*p4dp))) {
+ pudp = (void *)get_safe_page(GFP_ATOMIC);
+ if (!pudp)
+ return -ENOMEM;
+ p4d_populate(&init_mm, p4dp, pudp);
+ }
+
+ pudp = pud_offset(p4dp, dst_addr);
if (pud_none(READ_ONCE(*pudp))) {
pmdp = (void *)get_safe_page(GFP_ATOMIC);
if (!pmdp)
@@ -419,7 +428,7 @@ static int copy_pmd(pud_t *dst_pudp, pud_t *src_pudp, unsigned long start,
return 0;
}

-static int copy_pud(pgd_t *dst_pgdp, pgd_t *src_pgdp, unsigned long start,
+static int copy_pud(p4d_t *dst_p4dp, p4d_t *src_p4dp, unsigned long start,
unsigned long end)
{
pud_t *dst_pudp;
@@ -427,15 +436,15 @@ static int copy_pud(pgd_t *dst_pgdp, pgd_t *src_pgdp, unsigned long start,
unsigned long next;
unsigned long addr = start;

- if (pgd_none(READ_ONCE(*dst_pgdp))) {
+ if (p4d_none(READ_ONCE(*dst_p4dp))) {
dst_pudp = (pud_t *)get_safe_page(GFP_ATOMIC);
if (!dst_pudp)
return -ENOMEM;
- pgd_populate(&init_mm, dst_pgdp, dst_pudp);
+ p4d_populate(&init_mm, dst_p4dp, dst_pudp);
}
- dst_pudp = pud_offset(dst_pgdp, start);
+ dst_pudp = pud_offset(dst_p4dp, start);

- src_pudp = pud_offset(src_pgdp, start);
+ src_pudp = pud_offset(src_p4dp, start);
do {
pud_t pud = READ_ONCE(*src_pudp);

@@ -454,6 +463,27 @@ static int copy_pud(pgd_t *dst_pgdp, pgd_t *src_pgdp, unsigned long start,
return 0;
}

+static int copy_p4d(pgd_t *dst_pgdp, pgd_t *src_pgdp, unsigned long start,
+ unsigned long end)
+{
+ p4d_t *dst_p4dp;
+ p4d_t *src_p4dp;
+ unsigned long next;
+ unsigned long addr = start;
+
+ dst_p4dp = p4d_offset(dst_pgdp, start);
+ src_p4dp = p4d_offset(src_pgdp, start);
+ do {
+ next = p4d_addr_end(addr, end);
+ if (p4d_none(READ_ONCE(*src_p4dp)))
+ continue;
+ if (copy_pud(dst_p4dp, src_p4dp, addr, next))
+ return -ENOMEM;
+ } while (dst_p4dp++, src_p4dp++, addr = next, addr != end);
+
+ return 0;
+}
+
static int copy_page_tables(pgd_t *dst_pgdp, unsigned long start,
unsigned long end)
{
@@ -466,7 +496,7 @@ static int copy_page_tables(pgd_t *dst_pgdp, unsigned long start,
next = pgd_addr_end(addr, end);
if (pgd_none(READ_ONCE(*src_pgdp)))
continue;
- if (copy_pud(dst_pgdp, src_pgdp, addr, next))
+ if (copy_p4d(dst_pgdp, src_pgdp, addr, next))
return -ENOMEM;
} while (dst_pgdp++, src_pgdp++, addr = next, addr != end);

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index c9cedc0432d2..a529877daa13 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -145,6 +145,7 @@ static void show_pte(unsigned long addr)
pr_alert("[%016lx] pgd=%016llx", addr, pgd_val(pgd));

do {
+ p4d_t *p4dp, p4d;
pud_t *pudp, pud;
pmd_t *pmdp, pmd;
pte_t *ptep, pte;
@@ -152,7 +153,13 @@ static void show_pte(unsigned long addr)
if (pgd_none(pgd) || pgd_bad(pgd))
break;

- pudp = pud_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ p4d = READ_ONCE(*p4dp);
+ pr_cont(", p4d=%016llx", p4d_val(p4d));
+ if (p4d_none(p4d) || p4d_bad(p4d))
+ break;
+
+ pudp = pud_offset(p4dp, addr);
pud = READ_ONCE(*pudp);
pr_cont(", pud=%016llx", pud_val(pud));
if (pud_none(pud) || pud_bad(pud))
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index bbeb6a5a6ba6..b8a9f26f3790 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -67,11 +67,13 @@ static int find_num_contig(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, size_t *pgsize)
{
pgd_t *pgdp = pgd_offset(mm, addr);
+ p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;

*pgsize = PAGE_SIZE;
- pudp = pud_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ pudp = pud_offset(p4dp, addr);
pmdp = pmd_offset(pudp, addr);
if ((pte_t *)pmdp == ptep) {
*pgsize = PMD_SIZE;
@@ -217,12 +219,14 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep = NULL;

pgdp = pgd_offset(mm, addr);
- pudp = pud_alloc(mm, pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ pudp = pud_alloc(mm, p4dp, addr);
if (!pudp)
return NULL;

@@ -259,6 +263,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp, pud;
pmd_t *pmdp, pmd;

@@ -266,7 +271,11 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
if (!pgd_present(READ_ONCE(*pgdp)))
return NULL;

- pudp = pud_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ if (!p4d_present(READ_ONCE(*p4dp)))
+ return NULL;
+
+ pudp = pud_offset(p4dp, addr);
pud = READ_ONCE(*pudp);
if (sz != PUD_SIZE && pud_none(pud))
return NULL;
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index f87a32484ea8..2339811f317b 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -84,17 +84,17 @@ static pmd_t *__init kasan_pmd_offset(pud_t *pudp, unsigned long addr, int node,
return early ? pmd_offset_kimg(pudp, addr) : pmd_offset(pudp, addr);
}

-static pud_t *__init kasan_pud_offset(pgd_t *pgdp, unsigned long addr, int node,
+static pud_t *__init kasan_pud_offset(p4d_t *p4dp, unsigned long addr, int node,
bool early)
{
- if (pgd_none(READ_ONCE(*pgdp))) {
+ if (p4d_none(READ_ONCE(*p4dp))) {
phys_addr_t pud_phys = early ?
__pa_symbol(kasan_early_shadow_pud)
: kasan_alloc_zeroed_page(node);
- __pgd_populate(pgdp, pud_phys, PMD_TYPE_TABLE);
+ __p4d_populate(p4dp, pud_phys, PMD_TYPE_TABLE);
}

- return early ? pud_offset_kimg(pgdp, addr) : pud_offset(pgdp, addr);
+ return early ? pud_offset_kimg(p4dp, addr) : pud_offset(p4dp, addr);
}

static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr,
@@ -126,11 +126,11 @@ static void __init kasan_pmd_populate(pud_t *pudp, unsigned long addr,
} while (pmdp++, addr = next, addr != end && pmd_none(READ_ONCE(*pmdp)));
}

-static void __init kasan_pud_populate(pgd_t *pgdp, unsigned long addr,
+static void __init kasan_pud_populate(p4d_t *p4dp, unsigned long addr,
unsigned long end, int node, bool early)
{
unsigned long next;
- pud_t *pudp = kasan_pud_offset(pgdp, addr, node, early);
+ pud_t *pudp = kasan_pud_offset(p4dp, addr, node, early);

do {
next = pud_addr_end(addr, end);
@@ -138,6 +138,18 @@ static void __init kasan_pud_populate(pgd_t *pgdp, unsigned long addr,
} while (pudp++, addr = next, addr != end && pud_none(READ_ONCE(*pudp)));
}

+static void __init kasan_p4d_populate(pgd_t *pgdp, unsigned long addr,
+ unsigned long end, int node, bool early)
+{
+ unsigned long next;
+ p4d_t *p4dp = p4d_offset(pgdp, addr);
+
+ do {
+ next = p4d_addr_end(addr, end);
+ kasan_pud_populate(p4dp, addr, next, node, early);
+ } while (p4dp++, addr = next, addr != end);
+}
+
static void __init kasan_pgd_populate(unsigned long addr, unsigned long end,
int node, bool early)
{
@@ -147,7 +159,7 @@ static void __init kasan_pgd_populate(unsigned long addr, unsigned long end,
pgdp = pgd_offset_k(addr);
do {
next = pgd_addr_end(addr, end);
- kasan_pud_populate(pgdp, addr, next, node, early);
+ kasan_p4d_populate(pgdp, addr, next, node, early);
} while (pgdp++, addr = next, addr != end);
}

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index a374e4f51a62..c4c2e36b80ab 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -290,18 +290,19 @@ static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end,
{
unsigned long next;
pud_t *pudp;
- pgd_t pgd = READ_ONCE(*pgdp);
+ p4d_t *p4dp = p4d_offset(pgdp, addr);
+ p4d_t p4d = READ_ONCE(*p4dp);

- if (pgd_none(pgd)) {
+ if (p4d_none(p4d)) {
phys_addr_t pud_phys;
BUG_ON(!pgtable_alloc);
pud_phys = pgtable_alloc(PUD_SHIFT);
- __pgd_populate(pgdp, pud_phys, PUD_TYPE_TABLE);
- pgd = READ_ONCE(*pgdp);
+ __p4d_populate(p4dp, pud_phys, PUD_TYPE_TABLE);
+ p4d = READ_ONCE(*p4dp);
}
- BUG_ON(pgd_bad(pgd));
+ BUG_ON(p4d_bad(p4d));

- pudp = pud_set_fixmap_offset(pgdp, addr);
+ pudp = pud_set_fixmap_offset(p4dp, addr);
do {
pud_t old_pud = READ_ONCE(*pudp);

@@ -648,6 +649,7 @@ static void __init map_kernel(pgd_t *pgdp)
READ_ONCE(*pgd_offset_k(FIXADDR_START)));
} else if (CONFIG_PGTABLE_LEVELS > 3) {
pgd_t *bm_pgdp;
+ p4d_t *bm_p4dp;
pud_t *bm_pudp;
/*
* The fixmap shares its top level pgd entry with the kernel
@@ -657,7 +659,8 @@ static void __init map_kernel(pgd_t *pgdp)
*/
BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
bm_pgdp = pgd_offset_raw(pgdp, FIXADDR_START);
- bm_pudp = pud_set_fixmap_offset(bm_pgdp, FIXADDR_START);
+ bm_p4dp = p4d_offset(bm_pgdp, FIXADDR_START);
+ bm_pudp = pud_set_fixmap_offset(bm_p4dp, FIXADDR_START);
pud_populate(&init_mm, bm_pudp, lm_alias(bm_pmd));
pud_clear_fixmap();
} else {
@@ -691,6 +694,7 @@ void __init paging_init(void)
int kern_addr_valid(unsigned long addr)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp, pud;
pmd_t *pmdp, pmd;
pte_t *ptep, pte;
@@ -702,7 +706,11 @@ int kern_addr_valid(unsigned long addr)
if (pgd_none(READ_ONCE(*pgdp)))
return 0;

- pudp = pud_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ if (p4d_none(READ_ONCE(*p4dp)))
+ return 0;
+
+ pudp = pud_offset(p4dp, addr);
pud = READ_ONCE(*pudp);
if (pud_none(pud))
return 0;
@@ -1045,6 +1053,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
unsigned long addr = start;
unsigned long next;
pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;

@@ -1055,7 +1064,11 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
if (!pgdp)
return -ENOMEM;

- pudp = vmemmap_pud_populate(pgdp, addr, node);
+ p4dp = vmemmap_p4d_populate(pgdp, addr, node);
+ if (!p4dp)
+ return -ENOMEM;
+
+ pudp = vmemmap_pud_populate(p4dp, addr, node);
if (!pudp)
return -ENOMEM;

@@ -1090,11 +1103,12 @@ void vmemmap_free(unsigned long start, unsigned long end,
static inline pud_t * fixmap_pud(unsigned long addr)
{
pgd_t *pgdp = pgd_offset_k(addr);
- pgd_t pgd = READ_ONCE(*pgdp);
+ p4d_t *p4dp = p4d_offset(pgdp, addr);
+ p4d_t p4d = READ_ONCE(*p4dp);

- BUG_ON(pgd_none(pgd) || pgd_bad(pgd));
+ BUG_ON(p4d_none(p4d) || p4d_bad(p4d));

- return pud_offset_kimg(pgdp, addr);
+ return pud_offset_kimg(p4dp, addr);
}

static inline pmd_t * fixmap_pmd(unsigned long addr)
@@ -1120,25 +1134,27 @@ static inline pte_t * fixmap_pte(unsigned long addr)
*/
void __init early_fixmap_init(void)
{
- pgd_t *pgdp, pgd;
+ pgd_t *pgdp;
+ p4d_t *p4dp, p4d;
pud_t *pudp;
pmd_t *pmdp;
unsigned long addr = FIXADDR_START;

pgdp = pgd_offset_k(addr);
- pgd = READ_ONCE(*pgdp);
+ p4dp = p4d_offset(pgdp, addr);
+ p4d = READ_ONCE(*p4dp);
if (CONFIG_PGTABLE_LEVELS > 3 &&
- !(pgd_none(pgd) || pgd_page_paddr(pgd) == __pa_symbol(bm_pud))) {
+ !(p4d_none(p4d) || p4d_page_paddr(p4d) == __pa_symbol(bm_pud))) {
/*
* We only end up here if the kernel mapping and the fixmap
* share the top level pgd entry, which should only happen on
* 16k/4 levels configurations.
*/
BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
- pudp = pud_offset_kimg(pgdp, addr);
+ pudp = pud_offset_kimg(p4dp, addr);
} else {
- if (pgd_none(pgd))
- __pgd_populate(pgdp, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
+ if (p4d_none(p4d))
+ __p4d_populate(p4dp, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
pudp = fixmap_pud(addr);
}
if (pud_none(READ_ONCE(*pudp)))
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 250c49008d73..5a310991ff73 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -198,6 +198,7 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
bool kernel_page_present(struct page *page)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
pud_t *pudp, pud;
pmd_t *pmdp, pmd;
pte_t *ptep;
@@ -210,7 +211,11 @@ bool kernel_page_present(struct page *page)
if (pgd_none(READ_ONCE(*pgdp)))
return false;

- pudp = pud_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ if (p4d_none(READ_ONCE(*p4dp)))
+ return false;
+
+ pudp = pud_offset(p4dp, addr);
pud = READ_ONCE(*pudp);
if (pud_none(pud))
return false;
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index e3b9ee268823..48d4288c5f1b 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -158,13 +158,22 @@ static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)

static void clear_stage2_pgd_entry(struct kvm *kvm, pgd_t *pgd, phys_addr_t addr)
{
- pud_t *pud_table __maybe_unused = stage2_pud_offset(kvm, pgd, 0UL);
+ p4d_t *p4d_table __maybe_unused = stage2_p4d_offset(kvm, pgd, 0UL);
stage2_pgd_clear(kvm, pgd);
kvm_tlb_flush_vmid_ipa(kvm, addr);
- stage2_pud_free(kvm, pud_table);
+ stage2_p4d_free(kvm, p4d_table);
put_page(virt_to_page(pgd));
}

+static void clear_stage2_p4d_entry(struct kvm *kvm, p4d_t *p4d, phys_addr_t addr)
+{
+ pud_t *pud_table __maybe_unused = stage2_pud_offset(kvm, p4d, 0);
+ stage2_p4d_clear(kvm, p4d);
+ kvm_tlb_flush_vmid_ipa(kvm, addr);
+ stage2_pud_free(kvm, pud_table);
+ put_page(virt_to_page(p4d));
+}
+
static void clear_stage2_pud_entry(struct kvm *kvm, pud_t *pud, phys_addr_t addr)
{
pmd_t *pmd_table __maybe_unused = stage2_pmd_offset(kvm, pud, 0);
@@ -208,12 +217,20 @@ static inline void kvm_pud_populate(pud_t *pudp, pmd_t *pmdp)
dsb(ishst);
}

-static inline void kvm_pgd_populate(pgd_t *pgdp, pud_t *pudp)
+static inline void kvm_p4d_populate(p4d_t *p4dp, pud_t *pudp)
{
- WRITE_ONCE(*pgdp, kvm_mk_pgd(pudp));
+ WRITE_ONCE(*p4dp, kvm_mk_p4d(pudp));
dsb(ishst);
}

+static inline void kvm_pgd_populate(pgd_t *pgdp, p4d_t *p4dp)
+{
+#ifndef __PAGETABLE_P4D_FOLDED
+ WRITE_ONCE(*pgdp, kvm_mk_pgd(p4dp));
+ dsb(ishst);
+#endif
+}
+
/*
* Unmapping vs dcache management:
*
@@ -293,13 +310,13 @@ static void unmap_stage2_pmds(struct kvm *kvm, pud_t *pud,
clear_stage2_pud_entry(kvm, pud, start_addr);
}

-static void unmap_stage2_puds(struct kvm *kvm, pgd_t *pgd,
+static void unmap_stage2_puds(struct kvm *kvm, p4d_t *p4d,
phys_addr_t addr, phys_addr_t end)
{
phys_addr_t next, start_addr = addr;
pud_t *pud, *start_pud;

- start_pud = pud = stage2_pud_offset(kvm, pgd, addr);
+ start_pud = pud = stage2_pud_offset(kvm, p4d, addr);
do {
next = stage2_pud_addr_end(kvm, addr, end);
if (!stage2_pud_none(kvm, *pud)) {
@@ -317,6 +334,23 @@ static void unmap_stage2_puds(struct kvm *kvm, pgd_t *pgd,
} while (pud++, addr = next, addr != end);

if (stage2_pud_table_empty(kvm, start_pud))
+ clear_stage2_p4d_entry(kvm, p4d, start_addr);
+}
+
+static void unmap_stage2_p4ds(struct kvm *kvm, pgd_t *pgd,
+ phys_addr_t addr, phys_addr_t end)
+{
+ phys_addr_t next, start_addr = addr;
+ p4d_t *p4d, *start_p4d;
+
+ start_p4d = p4d = stage2_p4d_offset(kvm, pgd, addr);
+ do {
+ next = stage2_p4d_addr_end(kvm, addr, end);
+ if (!stage2_p4d_none(kvm, *p4d))
+ unmap_stage2_puds(kvm, p4d, addr, next);
+ } while (p4d++, addr = next, addr != end);
+
+ if (stage2_p4d_table_empty(kvm, start_p4d))
clear_stage2_pgd_entry(kvm, pgd, start_addr);
}

@@ -351,7 +385,7 @@ static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
break;
next = stage2_pgd_addr_end(kvm, addr, end);
if (!stage2_pgd_none(kvm, *pgd))
- unmap_stage2_puds(kvm, pgd, addr, next);
+ unmap_stage2_p4ds(kvm, pgd, addr, next);
/*
* If the range is too large, release the kvm->mmu_lock
* to prevent starvation and lockup detector warnings.
@@ -391,13 +425,13 @@ static void stage2_flush_pmds(struct kvm *kvm, pud_t *pud,
} while (pmd++, addr = next, addr != end);
}

-static void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd,
+static void stage2_flush_puds(struct kvm *kvm, p4d_t *p4d,
phys_addr_t addr, phys_addr_t end)
{
pud_t *pud;
phys_addr_t next;

- pud = stage2_pud_offset(kvm, pgd, addr);
+ pud = stage2_pud_offset(kvm, p4d, addr);
do {
next = stage2_pud_addr_end(kvm, addr, end);
if (!stage2_pud_none(kvm, *pud)) {
@@ -409,6 +443,20 @@ static void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd,
} while (pud++, addr = next, addr != end);
}

+static void stage2_flush_p4ds(struct kvm *kvm, pgd_t *pgd,
+ phys_addr_t addr, phys_addr_t end)
+{
+ p4d_t *p4d;
+ phys_addr_t next;
+
+ p4d = stage2_p4d_offset(kvm, pgd, addr);
+ do {
+ next = stage2_p4d_addr_end(kvm, addr, end);
+ if (!stage2_p4d_none(kvm, *p4d))
+ stage2_flush_puds(kvm, p4d, addr, next);
+ } while (p4d++, addr = next, addr != end);
+}
+
static void stage2_flush_memslot(struct kvm *kvm,
struct kvm_memory_slot *memslot)
{
@@ -421,7 +469,7 @@ static void stage2_flush_memslot(struct kvm *kvm,
do {
next = stage2_pgd_addr_end(kvm, addr, end);
if (!stage2_pgd_none(kvm, *pgd))
- stage2_flush_puds(kvm, pgd, addr, next);
+ stage2_flush_p4ds(kvm, pgd, addr, next);
} while (pgd++, addr = next, addr != end);
}

@@ -451,12 +499,21 @@ static void stage2_flush_vm(struct kvm *kvm)

static void clear_hyp_pgd_entry(pgd_t *pgd)
{
- pud_t *pud_table __maybe_unused = pud_offset(pgd, 0UL);
+ p4d_t *p4d_table __maybe_unused = p4d_offset(pgd, 0UL);
pgd_clear(pgd);
- pud_free(NULL, pud_table);
+ p4d_free(NULL, p4d_table);
put_page(virt_to_page(pgd));
}

+static void clear_hyp_p4d_entry(p4d_t *p4d)
+{
+ pud_t *pud_table __maybe_unused = pud_offset(p4d, 0);
+ VM_BUG_ON(p4d_huge(*p4d));
+ p4d_clear(p4d);
+ pud_free(NULL, pud_table);
+ put_page(virt_to_page(p4d));
+}
+
static void clear_hyp_pud_entry(pud_t *pud)
{
pmd_t *pmd_table __maybe_unused = pmd_offset(pud, 0);
@@ -508,12 +565,12 @@ static void unmap_hyp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end)
clear_hyp_pud_entry(pud);
}

-static void unmap_hyp_puds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end)
+static void unmap_hyp_puds(p4d_t *p4d, phys_addr_t addr, phys_addr_t end)
{
phys_addr_t next;
pud_t *pud, *start_pud;

- start_pud = pud = pud_offset(pgd, addr);
+ start_pud = pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
/* Hyp doesn't use huge puds */
@@ -522,6 +579,23 @@ static void unmap_hyp_puds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end)
} while (pud++, addr = next, addr != end);

if (hyp_pud_table_empty(start_pud))
+ clear_hyp_p4d_entry(p4d);
+}
+
+static void unmap_hyp_p4ds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end)
+{
+ phys_addr_t next;
+ p4d_t *p4d, *start_p4d;
+
+ start_p4d = p4d = p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+ /* Hyp doesn't use huge p4ds */
+ if (!p4d_none(*p4d))
+ unmap_hyp_puds(p4d, addr, next);
+ } while (p4d++, addr = next, addr != end);
+
+ if (hyp_p4d_table_empty(start_p4d))
clear_hyp_pgd_entry(pgd);
}

@@ -545,7 +619,7 @@ static void __unmap_hyp_range(pgd_t *pgdp, unsigned long ptrs_per_pgd,
do {
next = pgd_addr_end(addr, end);
if (!pgd_none(*pgd))
- unmap_hyp_puds(pgd, addr, next);
+ unmap_hyp_p4ds(pgd, addr, next);
} while (pgd++, addr = next, addr != end);
}

@@ -655,7 +729,7 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
return 0;
}

-static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start,
+static int create_hyp_pud_mappings(p4d_t *p4d, unsigned long start,
unsigned long end, unsigned long pfn,
pgprot_t prot)
{
@@ -666,7 +740,7 @@ static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start,

addr = start;
do {
- pud = pud_offset(pgd, addr);
+ pud = pud_offset(p4d, addr);

if (pud_none_or_clear_bad(pud)) {
pmd = pmd_alloc_one(NULL, addr);
@@ -688,12 +762,45 @@ static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start,
return 0;
}

+static int create_hyp_p4d_mappings(pgd_t *pgd, unsigned long start,
+ unsigned long end, unsigned long pfn,
+ pgprot_t prot)
+{
+ p4d_t *p4d;
+ pud_t *pud;
+ unsigned long addr, next;
+ int ret;
+
+ addr = start;
+ do {
+ p4d = p4d_offset(pgd, addr);
+
+ if (p4d_none(*p4d)) {
+ pud = pud_alloc_one(NULL, addr);
+ if (!pud) {
+ kvm_err("Cannot allocate Hyp pud\n");
+ return -ENOMEM;
+ }
+ kvm_p4d_populate(p4d, pud);
+ get_page(virt_to_page(p4d));
+ }
+
+ next = p4d_addr_end(addr, end);
+ ret = create_hyp_pud_mappings(p4d, addr, next, pfn, prot);
+ if (ret)
+ return ret;
+ pfn += (next - addr) >> PAGE_SHIFT;
+ } while (addr = next, addr != end);
+
+ return 0;
+}
+
static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd,
unsigned long start, unsigned long end,
unsigned long pfn, pgprot_t prot)
{
pgd_t *pgd;
- pud_t *pud;
+ p4d_t *p4d;
unsigned long addr, next;
int err = 0;

@@ -704,18 +811,18 @@ static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd,
pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd);

if (pgd_none(*pgd)) {
- pud = pud_alloc_one(NULL, addr);
- if (!pud) {
- kvm_err("Cannot allocate Hyp pud\n");
+ p4d = p4d_alloc_one(NULL, addr);
+ if (!p4d) {
+ kvm_err("Cannot allocate Hyp p4d\n");
err = -ENOMEM;
goto out;
}
- kvm_pgd_populate(pgd, pud);
+ kvm_pgd_populate(pgd, p4d);
get_page(virt_to_page(pgd));
}

next = pgd_addr_end(addr, end);
- err = create_hyp_pud_mappings(pgd, addr, next, pfn, prot);
+ err = create_hyp_p4d_mappings(pgd, addr, next, pfn, prot);
if (err)
goto out;
pfn += (next - addr) >> PAGE_SHIFT;
@@ -1012,22 +1119,40 @@ void kvm_free_stage2_pgd(struct kvm *kvm)
free_pages_exact(pgd, stage2_pgd_size(kvm));
}

-static pud_t *stage2_get_pud(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
+static p4d_t *stage2_get_p4d(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
phys_addr_t addr)
{
pgd_t *pgd;
- pud_t *pud;
+ p4d_t *p4d;

pgd = kvm->arch.pgd + stage2_pgd_index(kvm, addr);
if (stage2_pgd_none(kvm, *pgd)) {
if (!cache)
return NULL;
- pud = mmu_memory_cache_alloc(cache);
- stage2_pgd_populate(kvm, pgd, pud);
+ p4d = mmu_memory_cache_alloc(cache);
+ stage2_pgd_populate(kvm, pgd, p4d);
get_page(virt_to_page(pgd));
}

- return stage2_pud_offset(kvm, pgd, addr);
+ return stage2_p4d_offset(kvm, pgd, addr);
+}
+
+static pud_t *stage2_get_pud(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
+ phys_addr_t addr)
+{
+ p4d_t *p4d;
+ pud_t *pud;
+
+ p4d = stage2_get_p4d(kvm, cache, addr);
+ if (stage2_p4d_none(kvm, *p4d)) {
+ if (!cache)
+ return NULL;
+ pud = mmu_memory_cache_alloc(cache);
+ stage2_p4d_populate(kvm, p4d, pud);
+ get_page(virt_to_page(p4d));
+ }
+
+ return stage2_pud_offset(kvm, p4d, addr);
}

static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
@@ -1461,18 +1586,18 @@ static void stage2_wp_pmds(struct kvm *kvm, pud_t *pud,
}

/**
- * stage2_wp_puds - write protect PGD range
+ * stage2_wp_puds - write protect P4D range
* @pgd: pointer to pgd entry
* @addr: range start address
* @end: range end address
*/
-static void stage2_wp_puds(struct kvm *kvm, pgd_t *pgd,
+static void stage2_wp_puds(struct kvm *kvm, p4d_t *p4d,
phys_addr_t addr, phys_addr_t end)
{
pud_t *pud;
phys_addr_t next;

- pud = stage2_pud_offset(kvm, pgd, addr);
+ pud = stage2_pud_offset(kvm, p4d, addr);
do {
next = stage2_pud_addr_end(kvm, addr, end);
if (!stage2_pud_none(kvm, *pud)) {
@@ -1486,6 +1611,26 @@ static void stage2_wp_puds(struct kvm *kvm, pgd_t *pgd,
} while (pud++, addr = next, addr != end);
}

+/**
+ * stage2_wp_p4ds - write protect PGD range
+ * @pgd: pointer to pgd entry
+ * @addr: range start address
+ * @end: range end address
+ */
+static void stage2_wp_p4ds(struct kvm *kvm, pgd_t *pgd,
+ phys_addr_t addr, phys_addr_t end)
+{
+ p4d_t *p4d;
+ phys_addr_t next;
+
+ p4d = stage2_p4d_offset(kvm, pgd, addr);
+ do {
+ next = stage2_p4d_addr_end(kvm, addr, end);
+ if (!stage2_p4d_none(kvm, *p4d))
+ stage2_wp_puds(kvm, p4d, addr, next);
+ } while (p4d++, addr = next, addr != end);
+}
+
/**
* stage2_wp_range() - write protect stage2 memory region range
* @kvm: The KVM pointer
@@ -1513,7 +1658,7 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
break;
next = stage2_pgd_addr_end(kvm, addr, end);
if (stage2_pgd_present(kvm, *pgd))
- stage2_wp_puds(kvm, pgd, addr, next);
+ stage2_wp_p4ds(kvm, pgd, addr, next);
} while (pgd++, addr = next, addr != end);
}

--
2.25.1