[PATCH mm-unstable RFC 14/26] nios2/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE
From: David Hildenbrand <hidden>
Date: 2022-12-06 14:54:08
Also in:
linux-alpha, linux-m68k, linux-mips, linux-mm, linux-riscv, linux-s390, linux-sh, linux-um, linuxppc-dev, lkml, loongarch, sparclinux
Subsystem:
nios2 architecture, the rest · Maintainers:
Dinh Nguyen, Simon Schuster, Linus Torvalds
Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by using the yet-unused bit 31. Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: David Hildenbrand <redacted> --- arch/nios2/include/asm/pgtable-bits.h | 3 +++ arch/nios2/include/asm/pgtable.h | 22 +++++++++++++++++++++- 2 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/arch/nios2/include/asm/pgtable-bits.h b/arch/nios2/include/asm/pgtable-bits.h
index bfddff383e89..724f9b08b1d1 100644
--- a/arch/nios2/include/asm/pgtable-bits.h
+++ b/arch/nios2/include/asm/pgtable-bits.h@@ -31,4 +31,7 @@ #define _PAGE_ACCESSED (1<<26) /* page referenced */ #define _PAGE_DIRTY (1<<27) /* dirty page */ +/* We borrow bit 31 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE (1<<31) + #endif /* _ASM_NIOS2_PGTABLE_BITS_H */
diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
index d1e5c9eb4643..05999da01731 100644
--- a/arch/nios2/include/asm/pgtable.h
+++ b/arch/nios2/include/asm/pgtable.h@@ -239,7 +239,9 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) * * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 - * 0 < type -> 0 0 0 0 0 0 <-------------- offset ---------------> + * E < type -> 0 0 0 0 0 0 <-------------- offset ---------------> + * + * E is the exclusive marker that is not stored in swap entries. * * Note that the offset field is always non-zero if the swap type is 0, thus * !pte_none() is always true.
@@ -251,6 +253,24 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + extern void __init paging_init(void); extern void __init mmu_init(void);
--
2.38.1
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