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From:   Steven Price <steven.price@arm.com>
To:     linux-mm@kvack.org
Cc:     Steven Price <steven.price@arm.com>,
        Andy Lutomirski <luto@kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Arnd Bergmann <arnd@arndb.de>, Borislav Petkov <bp@alien8.de>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>,
        James Morse <james.morse@arm.com>,
        =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= <jglisse@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Will Deacon <will.deacon@arm.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH 01/13] arm64: mm: Add p?d_large() definitions
Date:   Fri, 15 Feb 2019 17:02:22 +0000
Message-Id: <20190215170235.23360-2-steven.price@arm.com>
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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