arm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS

ARM64_SWAPPER_USES_SECTION_MAPS implies that a PMD level huge page mappings
are used for swapper, idmap and vmemmap. Lets make it PMD explicit removing
any possible confusion with generic memory sections and also bit generic as
it's applicable for idmap and vmemmap mappings as well. Hence rename it as
ARM64_KERNEL_USES_PMD_MAPS instead.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
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>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/1623991622-24294-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

Author: Anshuman Khandual

arch/arm64/include/asm/kernel-pgtable.h

@@ -18,9 +18,9 @@
  * 64K (section size = 512M).
  */
 #ifdef CONFIG_ARM64_4K_PAGES
-#define ARM64_SWAPPER_USES_SECTION_MAPS 1
+#define ARM64_KERNEL_USES_PMD_MAPS 1
 #else
-#define ARM64_SWAPPER_USES_SECTION_MAPS 0
+#define ARM64_KERNEL_USES_PMD_MAPS 0
 #endif
 
 /*
@@ -33,7 +33,7 @@
  * VA range, so pages required to map highest possible PA are reserved in all
  * cases.
  */
-#if ARM64_SWAPPER_USES_SECTION_MAPS
+#if ARM64_KERNEL_USES_PMD_MAPS
 #define SWAPPER_PGTABLE_LEVELS	(CONFIG_PGTABLE_LEVELS - 1)
 #define IDMAP_PGTABLE_LEVELS	(ARM64_HW_PGTABLE_LEVELS(PHYS_MASK_SHIFT) - 1)
 #else
@@ -90,7 +90,7 @@
 #define IDMAP_DIR_SIZE		(IDMAP_PGTABLE_LEVELS * PAGE_SIZE)
 
 /* Initial memory map size */
-#if ARM64_SWAPPER_USES_SECTION_MAPS
+#if ARM64_KERNEL_USES_PMD_MAPS
 #define SWAPPER_BLOCK_SHIFT	PMD_SHIFT
 #define SWAPPER_BLOCK_SIZE	PMD_SIZE
 #define SWAPPER_TABLE_SHIFT	PUD_SHIFT
@@ -106,7 +106,7 @@
 #define SWAPPER_PTE_FLAGS	(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
 #define SWAPPER_PMD_FLAGS	(PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
 
-#if ARM64_SWAPPER_USES_SECTION_MAPS
+#if ARM64_KERNEL_USES_PMD_MAPS
 #define SWAPPER_MM_MMUFLAGS	(PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS)
 #else
 #define SWAPPER_MM_MMUFLAGS	(PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS)

arch/arm64/mm/mmu.c

@@ -1113,14 +1113,14 @@ static void free_empty_tables(unsigned long addr, unsigned long end,
 }
 #endif
 
-#if !ARM64_SWAPPER_USES_SECTION_MAPS
+#if !ARM64_KERNEL_USES_PMD_MAPS
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 		struct vmem_altmap *altmap)
 {
 	WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END));
 	return vmemmap_populate_basepages(start, end, node, altmap);
 }
-#else	/* !ARM64_SWAPPER_USES_SECTION_MAPS */
+#else	/* !ARM64_KERNEL_USES_PMD_MAPS */
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 		struct vmem_altmap *altmap)
 {
@@ -1165,7 +1165,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 
 	return 0;
 }
-#endif	/* !ARM64_SWAPPER_USES_SECTION_MAPS */
+#endif	/* !ARM64_KERNEL_USES_PMD_MAPS */
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 void vmemmap_free(unsigned long start, unsigned long end,