[PATCH 1/2] arm64: mm: add missing P4D definitions and use them consistently

Ard Biesheuvel ardb at kernel.org
Thu Mar 4 17:11:44 GMT 2021


Even though level 0, 1 and 2 descriptors share the same attribute
encodings, let's be a bit more consistent about using the right one at
the right level. So add new macros for level 0/P4D definitions, and
clean up some inconsistencies involving these macros.

Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/arm64/include/asm/pgtable-hwdef.h | 9 +++++++++
 arch/arm64/mm/mmu.c                    | 6 +++---
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h
index 42442a0ae2ab..e64e77a345b2 100644
--- a/arch/arm64/include/asm/pgtable-hwdef.h
+++ b/arch/arm64/include/asm/pgtable-hwdef.h
@@ -94,6 +94,15 @@
 /*
  * Hardware page table definitions.
  *
+ * Level 0 descriptor (P4D).
+ */
+#define P4D_TYPE_TABLE		(_AT(p4dval_t, 3) << 0)
+#define P4D_TABLE_BIT		(_AT(p4dval_t, 1) << 1)
+#define P4D_TYPE_MASK		(_AT(p4dval_t, 3) << 0)
+#define P4D_TYPE_SECT		(_AT(p4dval_t, 1) << 0)
+#define P4D_SECT_RDONLY		(_AT(p4dval_t, 1) << 7)		/* AP[2] */
+
+/*
  * Level 1 descriptor (PUD).
  */
 #define PUD_TYPE_TABLE		(_AT(pudval_t, 3) << 0)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 3802cfbdd20d..029091474042 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -309,7 +309,7 @@ static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end,
 		phys_addr_t pud_phys;
 		BUG_ON(!pgtable_alloc);
 		pud_phys = pgtable_alloc(PUD_SHIFT);
-		__p4d_populate(p4dp, pud_phys, PUD_TYPE_TABLE);
+		__p4d_populate(p4dp, pud_phys, P4D_TYPE_TABLE);
 		p4d = READ_ONCE(*p4dp);
 	}
 	BUG_ON(p4d_bad(p4d));
@@ -1209,11 +1209,11 @@ void __init early_fixmap_init(void)
 		pudp = pud_offset_kimg(p4dp, addr);
 	} else {
 		if (p4d_none(p4d))
-			__p4d_populate(p4dp, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
+			__p4d_populate(p4dp, __pa_symbol(bm_pud), P4D_TYPE_TABLE);
 		pudp = fixmap_pud(addr);
 	}
 	if (pud_none(READ_ONCE(*pudp)))
-		__pud_populate(pudp, __pa_symbol(bm_pmd), PMD_TYPE_TABLE);
+		__pud_populate(pudp, __pa_symbol(bm_pmd), PUD_TYPE_TABLE);
 	pmdp = fixmap_pmd(addr);
 	__pmd_populate(pmdp, __pa_symbol(bm_pte), PMD_TYPE_TABLE);
 
-- 
2.20.1




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