[PATCH v3 1/5] arch/x86: Drop own definition of pgd,p4d_leaf

[PATCH v3 1/5] arch/x86: Drop own definition of pgd,p4d_leaf

[Christophe Leroy]

From: Oscar Salvador <osalvador@suse.de>

We provide generic definitions of pXd_leaf in pgtable.h when the arch
do not define their own, where the generic pXd_leaf always return false.

Although x86 defines {pgd,p4d}_leaf, they end up being a no-op, so drop them
and make them fallback to the generic one.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
 arch/x86/include/asm/pgtable.h | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 65b8e5bb902c..772f778bac06 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -252,13 +252,6 @@ static inline unsigned long pgd_pfn(pgd_t pgd)
 	return (pgd_val(pgd) & PTE_PFN_MASK) >> PAGE_SHIFT;
 }
 
-#define p4d_leaf p4d_leaf
-static inline bool p4d_leaf(p4d_t p4d)
-{
-	/* No 512 GiB pages yet */
-	return 0;
-}
-
 #define pte_page(pte)	pfn_to_page(pte_pfn(pte))
 
 #define pmd_leaf pmd_leaf
@@ -1396,9 +1389,6 @@ static inline bool pgdp_maps_userspace(void *__ptr)
 	return (((ptr & ~PAGE_MASK) / sizeof(pgd_t)) < PGD_KERNEL_START);
 }
 
-#define pgd_leaf	pgd_leaf
-static inline bool pgd_leaf(pgd_t pgd) { return false; }
-
 #ifdef CONFIG_MITIGATION_PAGE_TABLE_ISOLATION
 /*
  * All top-level MITIGATION_PAGE_TABLE_ISOLATION page tables are order-1 pages
-- 
2.44.0

[PATCH v3 2/5] mm: Remove pud_user() from asm-generic/pgtable-nopmd.h

[Christophe Leroy]

Commit 2c8a81dc0cc5 ("riscv/mm: fix two page table check related
issues") added pud_user() in include/asm-generic/pgtable-nopmd.h

But pud_user() only exists on ARM64 and RISCV and is not expected
by any part of MM.

Add the missing definition in arch/riscv/include/asm/pgtable-32.h
and remove it from asm-generic/pgtable-nopmd.h

A stub pud_user() is also required for ARM64 after
commit ed928a3402d8 ("arm64/mm: fix page table check compile
error for CONFIG_PGTABLE_LEVELS=2")

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
---
v3: Added pud_user() for arm64
---
 arch/arm64/include/asm/pgtable.h    | 1 +
 arch/riscv/include/asm/pgtable-32.h | 5 +++++
 include/asm-generic/pgtable-nopmd.h | 1 -
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index f8efbc128446..c818b3328704 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -812,6 +812,7 @@ static inline pmd_t *pud_pgtable(pud_t pud)
 
 #define pud_valid(pud)		false
 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
+#define pud_user		false /* Always 0 with folding */
 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
 
 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
diff --git a/arch/riscv/include/asm/pgtable-32.h b/arch/riscv/include/asm/pgtable-32.h
index 00f3369570a8..37878ef37466 100644
--- a/arch/riscv/include/asm/pgtable-32.h
+++ b/arch/riscv/include/asm/pgtable-32.h
@@ -36,4 +36,9 @@
 static const __maybe_unused int pgtable_l4_enabled;
 static const __maybe_unused int pgtable_l5_enabled;
 
+static inline int pud_user(pud_t pud)
+{
+	return 0;
+}
+
 #endif /* _ASM_RISCV_PGTABLE_32_H */
diff --git a/include/asm-generic/pgtable-nopmd.h b/include/asm-generic/pgtable-nopmd.h
index 8ffd64e7a24c..b01349a312fa 100644
--- a/include/asm-generic/pgtable-nopmd.h
+++ b/include/asm-generic/pgtable-nopmd.h
@@ -30,7 +30,6 @@ typedef struct { pud_t pud; } pmd_t;
 static inline int pud_none(pud_t pud)		{ return 0; }
 static inline int pud_bad(pud_t pud)		{ return 0; }
 static inline int pud_present(pud_t pud)	{ return 1; }
-static inline int pud_user(pud_t pud)		{ return 0; }
 static inline int pud_leaf(pud_t pud)		{ return 0; }
 static inline void pud_clear(pud_t *pud)	{ }
 #define pmd_ERROR(pmd)				(pud_ERROR((pmd).pud))
-- 
2.44.0

[PATCH v3 3/5] LoongArch: Do not define pud_leaf() when there is no PMD

[Christophe Leroy]

pud_leaf() is already provided by asm-generic/pgtable-nopmd.h

Do not add a macro that hides and overrides the static inline
definition in asm-generic/pgtable-nopmd.h.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/loongarch/include/asm/pgtable.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index 161dd6e10479..da91b2d8bc6f 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -207,6 +207,7 @@ static inline pmd_t *pud_pgtable(pud_t pud)
 
 #define pud_phys(pud)		PHYSADDR(pud_val(pud))
 #define pud_page(pud)		(pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
+#define pud_leaf(pud)		((pud_val(pud) & _PAGE_HUGE) != 0)
 
 #endif
 
@@ -611,7 +612,6 @@ static inline long pmd_protnone(pmd_t pmd)
 #endif /* CONFIG_NUMA_BALANCING */
 
 #define pmd_leaf(pmd)		((pmd_val(pmd) & _PAGE_HUGE) != 0)
-#define pud_leaf(pud)		((pud_val(pud) & _PAGE_HUGE) != 0)
 
 /*
  * We provide our own get_unmapped area to cope with the virtual aliasing
-- 
2.44.0

[PATCH v3 4/5] mips: Do not define pud_leaf() when there is no PMD

[Christophe Leroy]

pud_leaf() is already provided by asm-generic/pgtable-nopmd.h

Do not add a macro that hides and overrides the static inline
definition in asm-generic/pgtable-nopmd.h.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/mips/include/asm/pgtable-64.h | 4 ++++
 arch/mips/include/asm/pgtable.h    | 1 -
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h
index 401c1d9e4409..d2de4e2800be 100644
--- a/arch/mips/include/asm/pgtable-64.h
+++ b/arch/mips/include/asm/pgtable-64.h
@@ -294,6 +294,10 @@ static inline void pud_clear(pud_t *pudp)
 {
 	pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
 }
+
+#ifdef _PAGE_HUGE
+#define pud_leaf(pud)	((pud_val(pud) & _PAGE_HUGE) != 0)
+#endif
 #endif
 
 #define pte_page(x)		pfn_to_page(pte_pfn(x))
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index c29a551eb0ca..28233025f884 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -755,7 +755,6 @@ static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
 
 #ifdef _PAGE_HUGE
 #define pmd_leaf(pmd)	((pmd_val(pmd) & _PAGE_HUGE) != 0)
-#define pud_leaf(pud)	((pud_val(pud) & _PAGE_HUGE) != 0)
 #endif
 
 #define gup_fast_permitted(start, end)	(!cpu_has_dc_aliases)
-- 
2.44.0

[PATCH v3 5/5] mm: Add p{g/4}d_leaf() in asm-generic/pgtable-nop{4/u}d.h

[Christophe Leroy]

Commit 2c8a81dc0cc5 ("riscv/mm: fix two page table check related
issues") added pud_leaf() in include/asm-generic/pgtable-nopmd.h

Do the same for p4d_leaf() and pgd_leaf() to avoid getting them
erroneously defined by architectures that do not implement the
related page level.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
v2: Added pXd_leaf macro as well in asm-generic/pgtable-nopXd.h to cohabit with the fallback
---
 include/asm-generic/pgtable-nop4d.h | 2 ++
 include/asm-generic/pgtable-nopmd.h | 1 +
 include/asm-generic/pgtable-nopud.h | 2 ++
 3 files changed, 5 insertions(+)

diff --git a/include/asm-generic/pgtable-nop4d.h b/include/asm-generic/pgtable-nop4d.h
index 03b7dae47dd4..ed7ba008469f 100644
--- a/include/asm-generic/pgtable-nop4d.h
+++ b/include/asm-generic/pgtable-nop4d.h
@@ -21,6 +21,8 @@ typedef struct { pgd_t pgd; } p4d_t;
 static inline int pgd_none(pgd_t pgd)		{ return 0; }
 static inline int pgd_bad(pgd_t pgd)		{ return 0; }
 static inline int pgd_present(pgd_t pgd)	{ return 1; }
+static inline int pgd_leaf(pgd_t pgd)		{ return 0; }
+#define pgd_leaf pgd_leaf
 static inline void pgd_clear(pgd_t *pgd)	{ }
 #define p4d_ERROR(p4d)				(pgd_ERROR((p4d).pgd))
 
diff --git a/include/asm-generic/pgtable-nopmd.h b/include/asm-generic/pgtable-nopmd.h
index b01349a312fa..e178ace2e23e 100644
--- a/include/asm-generic/pgtable-nopmd.h
+++ b/include/asm-generic/pgtable-nopmd.h
@@ -31,6 +31,7 @@ static inline int pud_none(pud_t pud)		{ return 0; }
 static inline int pud_bad(pud_t pud)		{ return 0; }
 static inline int pud_present(pud_t pud)	{ return 1; }
 static inline int pud_leaf(pud_t pud)		{ return 0; }
+#define pud_leaf pud_leaf
 static inline void pud_clear(pud_t *pud)	{ }
 #define pmd_ERROR(pmd)				(pud_ERROR((pmd).pud))
 
diff --git a/include/asm-generic/pgtable-nopud.h b/include/asm-generic/pgtable-nopud.h
index eb70c6d7ceff..655dfebea91c 100644
--- a/include/asm-generic/pgtable-nopud.h
+++ b/include/asm-generic/pgtable-nopud.h
@@ -28,6 +28,8 @@ typedef struct { p4d_t p4d; } pud_t;
 static inline int p4d_none(p4d_t p4d)		{ return 0; }
 static inline int p4d_bad(p4d_t p4d)		{ return 0; }
 static inline int p4d_present(p4d_t p4d)	{ return 1; }
+static inline int p4d_leaf(p4d_t p4d)		{ return 0; }
+#define p4d_leaf p4d_leaf
 static inline void p4d_clear(p4d_t *p4d)	{ }
 #define pud_ERROR(pud)				(p4d_ERROR((pud).p4d))
 
-- 
2.44.0

Re: [PATCH v3 1/5] arch/x86: Drop own definition of pgd,p4d_leaf

[Baoquan He]

On 07/13/24 at 09:08am, Christophe Leroy wrote:
> From: Oscar Salvador <osalvador@suse.de>
> 
> We provide generic definitions of pXd_leaf in pgtable.h when the arch
> do not define their own, where the generic pXd_leaf always return false.
> 
> Although x86 defines {pgd,p4d}_leaf, they end up being a no-op, so drop them
> and make them fallback to the generic one.
> 
> Signed-off-by: Oscar Salvador <osalvador@suse.de>
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> Reviewed-by: Peter Xu <peterx@redhat.com>
> ---
>  arch/x86/include/asm/pgtable.h | 10 ----------
>  1 file changed, 10 deletions(-)

Seems this series is missed. It does do a great clean up.

> 
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index 65b8e5bb902c..772f778bac06 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -252,13 +252,6 @@ static inline unsigned long pgd_pfn(pgd_t pgd)
>  	return (pgd_val(pgd) & PTE_PFN_MASK) >> PAGE_SHIFT;
>  }
>  
> -#define p4d_leaf p4d_leaf
> -static inline bool p4d_leaf(p4d_t p4d)
> -{
> -	/* No 512 GiB pages yet */
> -	return 0;
> -}
> -
>  #define pte_page(pte)	pfn_to_page(pte_pfn(pte))
>  
>  #define pmd_leaf pmd_leaf
> @@ -1396,9 +1389,6 @@ static inline bool pgdp_maps_userspace(void *__ptr)
>  	return (((ptr & ~PAGE_MASK) / sizeof(pgd_t)) < PGD_KERNEL_START);
>  }
>  
> -#define pgd_leaf	pgd_leaf
> -static inline bool pgd_leaf(pgd_t pgd) { return false; }
> -
>  #ifdef CONFIG_MITIGATION_PAGE_TABLE_ISOLATION
>  /*
>   * All top-level MITIGATION_PAGE_TABLE_ISOLATION page tables are order-1 pages
> -- 
> 2.44.0
> 
>