diff options
Diffstat (limited to 'kernel/arch/sparc/mm/tlb.c')
| -rw-r--r-- | kernel/arch/sparc/mm/tlb.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/kernel/arch/sparc/mm/tlb.c b/kernel/arch/sparc/mm/tlb.c new file mode 100644 index 000000000..9df2190c0 --- /dev/null +++ b/kernel/arch/sparc/mm/tlb.c @@ -0,0 +1,243 @@ +/* arch/sparc64/mm/tlb.c + * + * Copyright (C) 2004 David S. Miller <davem@redhat.com> + */ + +#include <linux/kernel.h> +#include <linux/percpu.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/preempt.h> + +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/tlbflush.h> +#include <asm/cacheflush.h> +#include <asm/mmu_context.h> +#include <asm/tlb.h> + +/* Heavily inspired by the ppc64 code. */ + +static DEFINE_PER_CPU(struct tlb_batch, tlb_batch); + +void flush_tlb_pending(void) +{ + struct tlb_batch *tb = &get_cpu_var(tlb_batch); + struct mm_struct *mm = tb->mm; + + if (!tb->tlb_nr) + goto out; + + flush_tsb_user(tb); + + if (CTX_VALID(mm->context)) { + if (tb->tlb_nr == 1) { + global_flush_tlb_page(mm, tb->vaddrs[0]); + } else { +#ifdef CONFIG_SMP + smp_flush_tlb_pending(tb->mm, tb->tlb_nr, + &tb->vaddrs[0]); +#else + __flush_tlb_pending(CTX_HWBITS(tb->mm->context), + tb->tlb_nr, &tb->vaddrs[0]); +#endif + } + } + + tb->tlb_nr = 0; + +out: + put_cpu_var(tlb_batch); +} + +void arch_enter_lazy_mmu_mode(void) +{ + struct tlb_batch *tb = this_cpu_ptr(&tlb_batch); + + tb->active = 1; +} + +void arch_leave_lazy_mmu_mode(void) +{ + struct tlb_batch *tb = this_cpu_ptr(&tlb_batch); + + if (tb->tlb_nr) + flush_tlb_pending(); + tb->active = 0; +} + +static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr, + bool exec) +{ + struct tlb_batch *tb = &get_cpu_var(tlb_batch); + unsigned long nr; + + vaddr &= PAGE_MASK; + if (exec) + vaddr |= 0x1UL; + + nr = tb->tlb_nr; + + if (unlikely(nr != 0 && mm != tb->mm)) { + flush_tlb_pending(); + nr = 0; + } + + if (!tb->active) { + flush_tsb_user_page(mm, vaddr); + global_flush_tlb_page(mm, vaddr); + goto out; + } + + if (nr == 0) + tb->mm = mm; + + tb->vaddrs[nr] = vaddr; + tb->tlb_nr = ++nr; + if (nr >= TLB_BATCH_NR) + flush_tlb_pending(); + +out: + put_cpu_var(tlb_batch); +} + +void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr, + pte_t *ptep, pte_t orig, int fullmm) +{ + if (tlb_type != hypervisor && + pte_dirty(orig)) { + unsigned long paddr, pfn = pte_pfn(orig); + struct address_space *mapping; + struct page *page; + + if (!pfn_valid(pfn)) + goto no_cache_flush; + + page = pfn_to_page(pfn); + if (PageReserved(page)) + goto no_cache_flush; + + /* A real file page? */ + mapping = page_mapping(page); + if (!mapping) + goto no_cache_flush; + + paddr = (unsigned long) page_address(page); + if ((paddr ^ vaddr) & (1 << 13)) + flush_dcache_page_all(mm, page); + } + +no_cache_flush: + if (!fullmm) + tlb_batch_add_one(mm, vaddr, pte_exec(orig)); +} + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr, + pmd_t pmd) +{ + unsigned long end; + pte_t *pte; + + pte = pte_offset_map(&pmd, vaddr); + end = vaddr + HPAGE_SIZE; + while (vaddr < end) { + if (pte_val(*pte) & _PAGE_VALID) { + bool exec = pte_exec(*pte); + + tlb_batch_add_one(mm, vaddr, exec); + } + pte++; + vaddr += PAGE_SIZE; + } + pte_unmap(pte); +} + +void set_pmd_at(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, pmd_t pmd) +{ + pmd_t orig = *pmdp; + + *pmdp = pmd; + + if (mm == &init_mm) + return; + + if ((pmd_val(pmd) ^ pmd_val(orig)) & _PAGE_PMD_HUGE) { + if (pmd_val(pmd) & _PAGE_PMD_HUGE) + mm->context.huge_pte_count++; + else + mm->context.huge_pte_count--; + + /* Do not try to allocate the TSB hash table if we + * don't have one already. We have various locks held + * and thus we'll end up doing a GFP_KERNEL allocation + * in an atomic context. + * + * Instead, we let the first TLB miss on a hugepage + * take care of this. + */ + } + + if (!pmd_none(orig)) { + addr &= HPAGE_MASK; + if (pmd_trans_huge(orig)) { + pte_t orig_pte = __pte(pmd_val(orig)); + bool exec = pte_exec(orig_pte); + + tlb_batch_add_one(mm, addr, exec); + tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec); + } else { + tlb_batch_pmd_scan(mm, addr, orig); + } + } +} + +void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp) +{ + pmd_t entry = *pmdp; + + pmd_val(entry) &= ~_PAGE_VALID; + + set_pmd_at(vma->vm_mm, address, pmdp, entry); + flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); +} + +void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, + pgtable_t pgtable) +{ + struct list_head *lh = (struct list_head *) pgtable; + + assert_spin_locked(&mm->page_table_lock); + + /* FIFO */ + if (!pmd_huge_pte(mm, pmdp)) + INIT_LIST_HEAD(lh); + else + list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp)); + pmd_huge_pte(mm, pmdp) = pgtable; +} + +pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) +{ + struct list_head *lh; + pgtable_t pgtable; + + assert_spin_locked(&mm->page_table_lock); + + /* FIFO */ + pgtable = pmd_huge_pte(mm, pmdp); + lh = (struct list_head *) pgtable; + if (list_empty(lh)) + pmd_huge_pte(mm, pmdp) = NULL; + else { + pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next; + list_del(lh); + } + pte_val(pgtable[0]) = 0; + pte_val(pgtable[1]) = 0; + + return pgtable; +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |