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