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 static DEFINE_PER_CPU(struct tlb_batch, tlb_batch);
  23
  24 void flush_tlb_pending(void)
  25 {
  26         struct tlb_batch *tb = &get_cpu_var(tlb_batch);
  27
  28         if (tb->tlb_nr) {
  29                 flush_tsb_user(tb);
  30
  31                 if (CTX_VALID(tb->mm->context)) {
  32 #ifdef CONFIG_SMP
  33                         smp_flush_tlb_pending(tb->mm, tb->tlb_nr,
  34                                               &tb->vaddrs[0]);
  35 #else
  36                         __flush_tlb_pending(CTX_HWBITS(tb->mm->context),
  37                                             tb->tlb_nr, &tb->vaddrs[0]);
  38 #endif
  39                 }
  40                 tb->tlb_nr = 0;
  41         }
  42
  43         put_cpu_var(tlb_batch);
  44 }
  45
  46 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
  47                    pte_t *ptep, pte_t orig, int fullmm)
  48 {
  49         struct tlb_batch *tb = &get_cpu_var(tlb_batch);
  50         unsigned long nr;
  51
  52         vaddr &= PAGE_MASK;
  53         if (pte_exec(orig))
  54                 vaddr |= 0x1UL;
  55
  56         if (tlb_type != hypervisor &&
  57             pte_dirty(orig)) {
  58                 unsigned long paddr, pfn = pte_pfn(orig);
  59                 struct address_space *mapping;
  60                 struct page *page;
  61
  62                 if (!pfn_valid(pfn))
  63                         goto no_cache_flush;
  64
  65                 page = pfn_to_page(pfn);
  66                 if (PageReserved(page))
  67                         goto no_cache_flush;
  68
  69                 /* A real file page? */
  70                 mapping = page_mapping(page);
  71                 if (!mapping)
  72                         goto no_cache_flush;
  73
  74                 paddr = (unsigned long) page_address(page);
  75                 if ((paddr ^ vaddr) & (1 << 13))
  76                         flush_dcache_page_all(mm, page);
  77         }
  78
  79 no_cache_flush:
  80
  81         if (fullmm) {
  82                 put_cpu_var(tlb_batch);
  83                 return;
  84         }
  85
  86         nr = tb->tlb_nr;
  87
  88         if (unlikely(nr != 0 && mm != tb->mm)) {
  89                 flush_tlb_pending();
  90                 nr = 0;
  91         }
  92
  93         if (nr == 0)
  94                 tb->mm = mm;
  95
  96         tb->vaddrs[nr] = vaddr;
  97         tb->tlb_nr = ++nr;
  98         if (nr >= TLB_BATCH_NR)
  99                 flush_tlb_pending();
 100
 101         put_cpu_var(tlb_batch);
 102 }