arch/sparc64/mm/tlb.c

   1 /* arch/sparc64/mm/tlb.c
   2  *
   3  * Copyright (C) 2004 David S. Miller <davem@redhat.com>
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/init.h>
   8 #include <linux/percpu.h>
   9 #include <linux/mm.h>
  10 #include <linux/swap.h>
  11 #include <linux/preempt.h>
  12
  13 #include <asm/pgtable.h>
  14 #include <asm/pgalloc.h>
  15 #include <asm/tlbflush.h>
  16 #include <asm/cacheflush.h>
  17 #include <asm/mmu_context.h>
  18 #include <asm/tlb.h>
  19
  20 /* Heavily inspired by the ppc64 code.  */
  21
  22 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers) = { 0, };
  23
  24 void flush_tlb_pending(void)
  25 {
  26         struct mmu_gather *mp;
  27
  28         preempt_disable();
  29
  30         mp = &__get_cpu_var(mmu_gathers);
  31         if (mp->tlb_nr) {
  32                 flush_tsb_user(mp);
  33
  34                 if (CTX_VALID(mp->mm->context)) {
  35 #ifdef CONFIG_SMP
  36                         smp_flush_tlb_pending(mp->mm, mp->tlb_nr,
  37                                               &mp->vaddrs[0]);
  38 #else
  39                         __flush_tlb_pending(CTX_HWBITS(mp->mm->context),
  40                                             mp->tlb_nr, &mp->vaddrs[0]);
  41 #endif
  42                 }
  43                 mp->tlb_nr = 0;
  44         }
  45
  46         preempt_enable();
  47 }
  48
  49 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr, pte_t *ptep, pte_t orig)
  50 {
  51         struct mmu_gather *mp = &__get_cpu_var(mmu_gathers);
  52         unsigned long nr;
  53
  54         vaddr &= PAGE_MASK;
  55         if (pte_exec(orig))
  56                 vaddr |= 0x1UL;
  57
  58         if (tlb_type != hypervisor &&
  59             pte_dirty(orig)) {
  60                 unsigned long paddr, pfn = pte_pfn(orig);
  61                 struct address_space *mapping;
  62                 struct page *page;
  63
  64                 if (!pfn_valid(pfn))
  65                         goto no_cache_flush;
  66
  67                 page = pfn_to_page(pfn);
  68                 if (PageReserved(page))
  69                         goto no_cache_flush;
  70
  71                 /* A real file page? */
  72                 mapping = page_mapping(page);
  73                 if (!mapping)
  74                         goto no_cache_flush;
  75
  76                 paddr = (unsigned long) page_address(page);
  77                 if ((paddr ^ vaddr) & (1 << 13))
  78                         flush_dcache_page_all(mm, page);
  79         }
  80
  81 no_cache_flush:
  82
  83         if (mp->fullmm)
  84                 return;
  85
  86         nr = mp->tlb_nr;
  87
  88         if (unlikely(nr != 0 && mm != mp->mm)) {
  89                 flush_tlb_pending();
  90                 nr = 0;
  91         }
  92
  93         if (nr == 0)
  94                 mp->mm = mm;
  95
  96         mp->vaddrs[nr] = vaddr;
  97         mp->tlb_nr = ++nr;
  98         if (nr >= TLB_BATCH_NR)
  99                 flush_tlb_pending();
 100 }