arch/sparc/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);
  23
  24 void flush_tlb_pending(void)
  25 {
  26         struct mmu_gather *mp = &get_cpu_var(mmu_gathers);
  27
  28         if (mp->tlb_nr) {
  29                 flush_tsb_user(mp);
  30
  31                 if (CTX_VALID(mp->mm->context)) {
  32 #ifdef CONFIG_SMP
  33                         smp_flush_tlb_pending(mp->mm, mp->tlb_nr,
  34                                               &mp->vaddrs[0]);
  35 #else
  36                         __flush_tlb_pending(CTX_HWBITS(mp->mm->context),
  37                                             mp->tlb_nr, &mp->vaddrs[0]);
  38 #endif
  39                 }
  40                 mp->tlb_nr = 0;
  41         }
  42
  43         put_cpu_var(mmu_gathers);
  44 }
  45
  46 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr, pte_t *ptep, pte_t orig)
  47 {
  48         struct mmu_gather *mp = &__get_cpu_var(mmu_gathers);
  49         unsigned long nr;
  50
  51         vaddr &= PAGE_MASK;
  52         if (pte_exec(orig))
  53                 vaddr |= 0x1UL;
  54
  55         if (tlb_type != hypervisor &&
  56             pte_dirty(orig)) {
  57                 unsigned long paddr, pfn = pte_pfn(orig);
  58                 struct address_space *mapping;
  59                 struct page *page;
  60
  61                 if (!pfn_valid(pfn))
  62                         goto no_cache_flush;
  63
  64                 page = pfn_to_page(pfn);
  65                 if (PageReserved(page))
  66                         goto no_cache_flush;
  67
  68                 /* A real file page? */
  69                 mapping = page_mapping(page);
  70                 if (!mapping)
  71                         goto no_cache_flush;
  72
  73                 paddr = (unsigned long) page_address(page);
  74                 if ((paddr ^ vaddr) & (1 << 13))
  75                         flush_dcache_page_all(mm, page);
  76         }
  77
  78 no_cache_flush:
  79
  80         if (mp->fullmm)
  81                 return;
  82
  83         nr = mp->tlb_nr;
  84
  85         if (unlikely(nr != 0 && mm != mp->mm)) {
  86                 flush_tlb_pending();
  87                 nr = 0;
  88         }
  89
  90         if (nr == 0)
  91                 mp->mm = mm;
  92
  93         mp->vaddrs[nr] = vaddr;
  94         mp->tlb_nr = ++nr;
  95         if (nr >= TLB_BATCH_NR)
  96                 flush_tlb_pending();
  97 }