[PATCH] mm: Move set_pxd_safe() helpers from generic to platform

[Anshuman Khandual]

set_pxd_safe() helpers that serve a specific purpose for both x86 and riscv
platforms, do not need to be in the common memory code. Otherwise they just
unnecessarily make the common API more complicated. This moves the helpers
from common code to platform instead.

Cc: Paul Walmsley <paul.walmsley at sifive.com>
Cc: Palmer Dabbelt <palmer at dabbelt.com>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: Dave Hansen <dave.hansen at linux.intel.com>
Cc: David Hildenbrand <david at redhat.com>
Cc: Ryan Roberts <ryan.roberts at arm.com>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: x86 at kernel.org
Cc: linux-mm at kvack.org
Cc: linux-riscv at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Suggested-by: David Hildenbrand <david at redhat.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual at arm.com>
---
 arch/riscv/include/asm/pgtable.h | 19 ++++++++++++++++
 arch/x86/include/asm/pgtable.h   | 37 +++++++++++++++++++++++++++++++
 include/linux/pgtable.h          | 38 --------------------------------
 3 files changed, 56 insertions(+), 38 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 089f3c9f56a3..39ca652c5ebe 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -957,6 +957,25 @@ void misc_mem_init(void);
 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
 
+/*
+ * Use set_p*_safe(), and elide TLB flushing, when confident that *no*
+ * TLB flush will be required as a result of the "set". For example, use
+ * in scenarios where it is known ahead of time that the routine is
+ * setting non-present entries, or re-setting an existing entry to the
+ * same value. Otherwise, use the typical "set" helpers and flush the
+ * TLB.
+ */
+#define set_p4d_safe(p4dp, p4d) \
+({ \
+	WARN_ON_ONCE(p4d_present(*p4dp) && !p4d_same(*p4dp, p4d)); \
+	set_p4d(p4dp, p4d); \
+})
+
+#define set_pgd_safe(pgdp, pgd) \
+({ \
+	WARN_ON_ONCE(pgd_present(*pgdp) && !pgd_same(*pgdp, pgd)); \
+	set_pgd(pgdp, pgd); \
+})
 #endif /* !__ASSEMBLY__ */
 
 #endif /* _ASM_RISCV_PGTABLE_H */
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index e39311a89bf4..fefb52bb6b4d 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1701,6 +1701,43 @@ bool arch_is_platform_page(u64 paddr);
 #define arch_is_platform_page arch_is_platform_page
 #endif
 
+/*
+ * Use set_p*_safe(), and elide TLB flushing, when confident that *no*
+ * TLB flush will be required as a result of the "set". For example, use
+ * in scenarios where it is known ahead of time that the routine is
+ * setting non-present entries, or re-setting an existing entry to the
+ * same value. Otherwise, use the typical "set" helpers and flush the
+ * TLB.
+ */
+#define set_pte_safe(ptep, pte) \
+({ \
+	WARN_ON_ONCE(pte_present(*ptep) && !pte_same(*ptep, pte)); \
+	set_pte(ptep, pte); \
+})
+
+#define set_pmd_safe(pmdp, pmd) \
+({ \
+	WARN_ON_ONCE(pmd_present(*pmdp) && !pmd_same(*pmdp, pmd)); \
+	set_pmd(pmdp, pmd); \
+})
+
+#define set_pud_safe(pudp, pud) \
+({ \
+	WARN_ON_ONCE(pud_present(*pudp) && !pud_same(*pudp, pud)); \
+	set_pud(pudp, pud); \
+})
+
+#define set_p4d_safe(p4dp, p4d) \
+({ \
+	WARN_ON_ONCE(p4d_present(*p4dp) && !p4d_same(*p4dp, p4d)); \
+	set_p4d(p4dp, p4d); \
+})
+
+#define set_pgd_safe(pgdp, pgd) \
+({ \
+	WARN_ON_ONCE(pgd_present(*pgdp) && !pgd_same(*pgdp, pgd)); \
+	set_pgd(pgdp, pgd); \
+})
 #endif	/* __ASSEMBLY__ */
 
 #endif /* _ASM_X86_PGTABLE_H */
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 2a6a3cccfc36..0bf88e505aad 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1050,44 +1050,6 @@ static inline int pgd_same(pgd_t pgd_a, pgd_t pgd_b)
 }
 #endif
 
-/*
- * Use set_p*_safe(), and elide TLB flushing, when confident that *no*
- * TLB flush will be required as a result of the "set". For example, use
- * in scenarios where it is known ahead of time that the routine is
- * setting non-present entries, or re-setting an existing entry to the
- * same value. Otherwise, use the typical "set" helpers and flush the
- * TLB.
- */
-#define set_pte_safe(ptep, pte) \
-({ \
-	WARN_ON_ONCE(pte_present(*ptep) && !pte_same(*ptep, pte)); \
-	set_pte(ptep, pte); \
-})
-
-#define set_pmd_safe(pmdp, pmd) \
-({ \
-	WARN_ON_ONCE(pmd_present(*pmdp) && !pmd_same(*pmdp, pmd)); \
-	set_pmd(pmdp, pmd); \
-})
-
-#define set_pud_safe(pudp, pud) \
-({ \
-	WARN_ON_ONCE(pud_present(*pudp) && !pud_same(*pudp, pud)); \
-	set_pud(pudp, pud); \
-})
-
-#define set_p4d_safe(p4dp, p4d) \
-({ \
-	WARN_ON_ONCE(p4d_present(*p4dp) && !p4d_same(*p4dp, p4d)); \
-	set_p4d(p4dp, p4d); \
-})
-
-#define set_pgd_safe(pgdp, pgd) \
-({ \
-	WARN_ON_ONCE(pgd_present(*pgdp) && !pgd_same(*pgdp, pgd)); \
-	set_pgd(pgdp, pgd); \
-})
-
 #ifndef __HAVE_ARCH_DO_SWAP_PAGE
 static inline void arch_do_swap_page_nr(struct mm_struct *mm,
 				     struct vm_area_struct *vma,
-- 
2.25.1