arm64/mm: Re-organize arch_make_huge_pte()

Core HugeTLB defines a fallback definition for arch_make_huge_pte(), which
calls platform provided pte_mkhuge(). But if any platform already provides
an override for arch_make_huge_pte(), then it does not need to provide the
helper pte_mkhuge().

arm64 override for arch_make_huge_pte() calls pte_mkhuge() internally, thus
creating an impression, that both of these callbacks are being used in core
HugeTLB and hence required to be defined. This drops off pte_mkhuge() which
was never required to begin with as there could not be any section mappings
at the PTE level. Re-organize arch_make_huge_pte() based on requested page
size and create the entry for the applicable page table level as needed. It
also removes a redundancy of clearing PTE_TABLE_BIT bit followed by setting
both PTE_TABLE_BIT and PTE_VALID bits (via PTE_TYPE_MASK) in the pte, while
creating CONT_PTE_SIZE size entries.

Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20241029044529.2624785-1-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index d56dbe5742d63089362730d01838dce86b7c68bf..609fd4447b1949e408de658eb72ad522e7658d11 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -438,11 +438,6 @@ static inline void __set_ptes(struct mm_struct *mm,
        }
 }
 
-/*
- * Huge pte definitions.
- */
-#define pte_mkhuge(pte)                (__pte(pte_val(pte) & ~PTE_TABLE_BIT))
-
 /*
  * Hugetlb definitions.
  */

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 5f1e2103888b76e50d589ffdfb70215db60f9a10..3215adf48a1b6c7a68f48b61bd2dbc21cd917450 100644 (file)
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -361,14 +361,25 @@ pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags)
 {
        size_t pagesize = 1UL << shift;
 
-       entry = pte_mkhuge(entry);
-       if (pagesize == CONT_PTE_SIZE) {
-               entry = pte_mkcont(entry);
-       } else if (pagesize == CONT_PMD_SIZE) {
+       switch (pagesize) {
+#ifndef __PAGETABLE_PMD_FOLDED
+       case PUD_SIZE:
+               entry = pud_pte(pud_mkhuge(pte_pud(entry)));
+               break;
+#endif
+       case CONT_PMD_SIZE:
                entry = pmd_pte(pmd_mkcont(pte_pmd(entry)));
-       } else if (pagesize != PUD_SIZE && pagesize != PMD_SIZE) {
+               fallthrough;
+       case PMD_SIZE:
+               entry = pmd_pte(pmd_mkhuge(pte_pmd(entry)));
+               break;
+       case CONT_PTE_SIZE:
+               entry = pte_mkcont(entry);
+               break;
+       default:
                pr_warn("%s: unrecognized huge page size 0x%lx\n",
                        __func__, pagesize);
+               break;
        }
        return entry;
 }