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 = &__get_cpu_var(mmu_gathers);
  27
  28         preempt_disable();
  29
  30         if (mp->tlb_nr) {
  31                 flush_tsb_user(mp);
  32
  33                 if (CTX_VALID(mp->mm->context)) {
  34 #ifdef CONFIG_SMP
  35                         smp_flush_tlb_pending(mp->mm, mp->tlb_nr,
  36                                               &mp->vaddrs[0]);
  37 #else
  38                         __flush_tlb_pending(CTX_HWBITS(mp->mm->context),
  39                                             mp->tlb_nr, &mp->vaddrs[0]);
  40 #endif
  41                 }
  42                 mp->tlb_nr = 0;
  43         }
  44
  45         preempt_enable();
  46 }
  47
  48 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr, pte_t *ptep, pte_t orig)
  49 {
  50         struct mmu_gather *mp = &__get_cpu_var(mmu_gathers);
  51         unsigned long nr;
  52
  53         vaddr &= PAGE_MASK;
  54         if (pte_exec(orig))
  55                 vaddr |= 0x1UL;
  56
  57         if (tlb_type != hypervisor &&
  58             pte_dirty(orig)) {
  59                 unsigned long paddr, pfn = pte_pfn(orig);
  60                 struct address_space *mapping;
  61                 struct page *page;
  62
  63                 if (!pfn_valid(pfn))
  64                         goto no_cache_flush;
  65
  66                 page = pfn_to_page(pfn);
  67                 if (PageReserved(page))
  68                         goto no_cache_flush;
  69
  70                 /* A real file page? */
  71                 mapping = page_mapping(page);
  72                 if (!mapping)
  73                         goto no_cache_flush;
  74
  75                 paddr = (unsigned long) page_address(page);
  76                 if ((paddr ^ vaddr) & (1 << 13))
  77                         flush_dcache_page_all(mm, page);
  78         }
  79
  80 no_cache_flush:
  81
  82         if (mp->fullmm)
  83                 return;
  84
  85         nr = mp->tlb_nr;
  86
  87         if (unlikely(nr != 0 && mm != mp->mm)) {
  88                 flush_tlb_pending();
  89                 nr = 0;
  90         }
  91
  92         if (nr == 0)
  93                 mp->mm = mm;
  94
  95         mp->vaddrs[nr] = vaddr;
  96         mp->tlb_nr = ++nr;
  97         if (nr >= TLB_BATCH_NR)
  98                 flush_tlb_pending();
  99 }