[PATCH 01/13] arm64: mm: Add p?d_large() definitions

Steven Price
2019-02-15T17:03:11Z

From: James Morse <james.morse@arm.com>

Exposing the pud/pgd levels of the page tables to walk_page_range() means
we may come across the exotic large mappings that come with large areas
of contiguous memory (such as the kernel's linear map).

Expose p?d_large() from each architecture to detect these large mappings.

arm64 already has these macros defined, but with a different name.
p?d_large() is used by s390, sparc and x86. Only arm/arm64 use p?d_sect().
Add a macro to allow both names.

By not providing a pgd_large(), we get the generic version that always
returns 0.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
---
arch/arm64/include/asm/pgtable.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index de70c1eabf33..09d308921625 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -428,6 +428,7 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
PMD_TYPE_TABLE)
#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
PMD_TYPE_SECT)
+#define pmd_large(x) pmd_sect(x)

#if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
#define pud_sect(pud) (0)
@@ -435,6 +436,7 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
#else
#define pud_sect(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \
PUD_TYPE_SECT)
+#define pud_large(x) pud_sect(x)
#define pud_table(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \
PUD_TYPE_TABLE)
#endif
--
2.20.1