diff options
Diffstat (limited to 'arch/powerpc/mm/book3s32/tlb.c')
| -rw-r--r-- | arch/powerpc/mm/book3s32/tlb.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/powerpc/mm/book3s32/tlb.c b/arch/powerpc/mm/book3s32/tlb.c new file mode 100644 index 000000000..9ad6b56bf --- /dev/null +++ b/arch/powerpc/mm/book3s32/tlb.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains the routines for TLB flushing. + * On machines where the MMU uses a hash table to store virtual to + * physical translations, these routines flush entries from the + * hash table also. + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + */ + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/highmem.h> +#include <linux/pagemap.h> +#include <linux/export.h> + +#include <asm/tlbflush.h> +#include <asm/tlb.h> + +#include <mm/mmu_decl.h> + +/* + * TLB flushing: + * + * - flush_tlb_mm(mm) flushes the specified mm context TLB's + * - flush_tlb_page(vma, vmaddr) flushes one page + * - flush_tlb_range(vma, start, end) flushes a range of pages + * - flush_tlb_kernel_range(start, end) flushes kernel pages + * + * since the hardware hash table functions as an extension of the + * tlb as far as the linux tables are concerned, flush it too. + * -- Cort + */ + +/* + * For each address in the range, find the pte for the address + * and check _PAGE_HASHPTE bit; if it is set, find and destroy + * the corresponding HPTE. + */ +void hash__flush_range(struct mm_struct *mm, unsigned long start, unsigned long end) +{ + pmd_t *pmd; + unsigned long pmd_end; + int count; + unsigned int ctx = mm->context.id; + + start &= PAGE_MASK; + if (start >= end) + return; + end = (end - 1) | ~PAGE_MASK; + pmd = pmd_off(mm, start); + for (;;) { + pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1; + if (pmd_end > end) + pmd_end = end; + if (!pmd_none(*pmd)) { + count = ((pmd_end - start) >> PAGE_SHIFT) + 1; + flush_hash_pages(ctx, start, pmd_val(*pmd), count); + } + if (pmd_end == end) + break; + start = pmd_end + 1; + ++pmd; + } +} +EXPORT_SYMBOL(hash__flush_range); + +/* + * Flush all the (user) entries for the address space described by mm. + */ +void hash__flush_tlb_mm(struct mm_struct *mm) +{ + struct vm_area_struct *mp; + VMA_ITERATOR(vmi, mm, 0); + + /* + * It is safe to iterate the vmas when called from dup_mmap, + * holding mmap_lock. It would also be safe from unmap_region + * or exit_mmap, but not from vmtruncate on SMP - but it seems + * dup_mmap is the only SMP case which gets here. + */ + for_each_vma(vmi, mp) + hash__flush_range(mp->vm_mm, mp->vm_start, mp->vm_end); +} +EXPORT_SYMBOL(hash__flush_tlb_mm); + +void hash__flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) +{ + struct mm_struct *mm; + pmd_t *pmd; + + mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm; + pmd = pmd_off(mm, vmaddr); + if (!pmd_none(*pmd)) + flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1); +} +EXPORT_SYMBOL(hash__flush_tlb_page); |