mm/arm64: merge pXd_huge() and pXd_leaf() definitions

Unlike most archs, aarch64 defines pXd_huge() and pXd_leaf() slightly
differently.  Redefine the pXd_huge() with pXd_leaf().

There used to be two traps for old aarch64 definitions over these APIs that
I found when reading the code around, they're:

 (1) 4797ec2dc83a ("arm64: fix pud_huge() for 2-level pagetables")
 (2) 23bc8f69f0ec ("arm64: mm: fix p?d_leaf()")

Define pXd_huge() with the current pXd_leaf() will make sure (2) isn't a
problem (on PROT_NONE checks).  To make sure it also works for (1), we
move over the __PAGETABLE_PMD_FOLDED check to pud_leaf(), allowing it to
constantly returning "false" for 2-level pgtables, which looks even safer
to cover both now.

Link: https://lkml.kernel.org/r/20240318200404.448346-9-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Mark Salter <msalter@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Konrad Dybcio <konrad.dybcio@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index afdd56d..ec406e7 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -709,7 +709,11 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 #define pud_none(pud)          (!pud_val(pud))
 #define pud_bad(pud)           (!pud_table(pud))
 #define pud_present(pud)       pte_present(pud_pte(pud))
+#ifndef __PAGETABLE_PMD_FOLDED
 #define pud_leaf(pud)          (pud_present(pud) && !pud_table(pud))
+#else
+#define pud_leaf(pud)          false
+#endif
 #define pud_valid(pud)         pte_valid(pud_pte(pud))
 #define pud_user(pud)          pte_user(pud_pte(pud))
 #define pud_user_exec(pud)     pte_user_exec(pud_pte(pud))

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 0f0e10b..1234bba 100644 (file)
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -81,16 +81,12 @@ bool arch_hugetlb_migration_supported(struct hstate *h)
 
 int pmd_huge(pmd_t pmd)
 {
-       return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
+       return pmd_leaf(pmd);
 }
 
 int pud_huge(pud_t pud)
 {
-#ifndef __PAGETABLE_PMD_FOLDED
-       return pud_val(pud) && !(pud_val(pud) & PUD_TABLE_BIT);
-#else
-       return 0;
-#endif
+       return pud_leaf(pud);
 }
 
 static int find_num_contig(struct mm_struct *mm, unsigned long addr,