arch/um/kernel/skas/tlb.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Copyright 2003 PathScale, Inc.
   4  * Licensed under the GPL
   5  */
   6
   7 #include "linux/stddef.h"
   8 #include "linux/sched.h"
   9 #include "linux/mm.h"
  10 #include "asm/page.h"
  11 #include "asm/pgtable.h"
  12 #include "asm/mmu.h"
  13 #include "mem_user.h"
  14 #include "mem.h"
  15 #include "skas.h"
  16 #include "os.h"
  17 #include "tlb.h"
  18
  19 static int do_ops(union mm_context *mmu, struct host_vm_op *ops, int last,
  20                   int finished, void **flush)
  21 {
  22         struct host_vm_op *op;
  23         int i, ret = 0;
  24
  25         for(i = 0; i <= last && !ret; i++){
  26                 op = &ops[i];
  27                 switch(op->type){
  28                 case MMAP:
  29                         ret = map(&mmu->skas.id, op->u.mmap.addr,
  30                                   op->u.mmap.len, op->u.mmap.r, op->u.mmap.w,
  31                                   op->u.mmap.x, op->u.mmap.fd,
  32                                   op->u.mmap.offset, finished, flush);
  33                         break;
  34                 case MUNMAP:
  35                         ret = unmap(&mmu->skas.id, op->u.munmap.addr,
  36                                     op->u.munmap.len, finished, flush);
  37                         break;
  38                 case MPROTECT:
  39                         ret = protect(&mmu->skas.id, op->u.mprotect.addr,
  40                                       op->u.mprotect.len, op->u.mprotect.r,
  41                                       op->u.mprotect.w, op->u.mprotect.x,
  42                                       finished, flush);
  43                         break;
  44                 default:
  45                         printk("Unknown op type %d in do_ops\n", op->type);
  46                         break;
  47                 }
  48         }
  49
  50         return ret;
  51 }
  52
  53 extern int proc_mm;
  54
  55 static void fix_range(struct mm_struct *mm, unsigned long start_addr,
  56                       unsigned long end_addr, int force)
  57 {
  58         if(!proc_mm && (end_addr > CONFIG_STUB_START))
  59                 end_addr = CONFIG_STUB_START;
  60
  61         fix_range_common(mm, start_addr, end_addr, force, do_ops);
  62 }
  63
  64 void __flush_tlb_one_skas(unsigned long addr)
  65 {
  66         flush_tlb_kernel_range_common(addr, addr + PAGE_SIZE);
  67 }
  68
  69 void flush_tlb_range_skas(struct vm_area_struct *vma, unsigned long start,
  70                      unsigned long end)
  71 {
  72         if(vma->vm_mm == NULL)
  73                 flush_tlb_kernel_range_common(start, end);
  74         else fix_range(vma->vm_mm, start, end, 0);
  75 }
  76
  77 void flush_tlb_mm_skas(struct mm_struct *mm)
  78 {
  79         unsigned long end;
  80
  81         /* Don't bother flushing if this address space is about to be
  82          * destroyed.
  83          */
  84         if(atomic_read(&mm->mm_users) == 0)
  85                 return;
  86
  87         end = proc_mm ? task_size : CONFIG_STUB_START;
  88         fix_range(mm, 0, end, 0);
  89 }
  90
  91 void force_flush_all_skas(void)
  92 {
  93         unsigned long end = proc_mm ? task_size : CONFIG_STUB_START;
  94         fix_range(current->mm, 0, end, 1);
  95 }
  96
  97 void flush_tlb_page_skas(struct vm_area_struct *vma, unsigned long address)
  98 {
  99         pgd_t *pgd;
 100         pud_t *pud;
 101         pmd_t *pmd;
 102         pte_t *pte;
 103         struct mm_struct *mm = vma->vm_mm;
 104         void *flush = NULL;
 105         int r, w, x, err = 0;
 106         struct mm_id *mm_id;
 107
 108         pgd = pgd_offset(vma->vm_mm, address);
 109         if(!pgd_present(*pgd))
 110                 goto kill;
 111
 112         pud = pud_offset(pgd, address);
 113         if(!pud_present(*pud))
 114                 goto kill;
 115
 116         pmd = pmd_offset(pud, address);
 117         if(!pmd_present(*pmd))
 118                 goto kill;
 119
 120         pte = pte_offset_kernel(pmd, address);
 121
 122         r = pte_read(*pte);
 123         w = pte_write(*pte);
 124         x = pte_exec(*pte);
 125         if (!pte_young(*pte)) {
 126                 r = 0;
 127                 w = 0;
 128         } else if (!pte_dirty(*pte)) {
 129                 w = 0;
 130         }
 131
 132         mm_id = &mm->context.skas.id;
 133         if(pte_newpage(*pte)){
 134                 if(pte_present(*pte)){
 135                         unsigned long long offset;
 136                         int fd;
 137
 138                         fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset);
 139                         err = map(mm_id, address, PAGE_SIZE, r, w, x, fd,
 140                                   offset, 1, &flush);
 141                 }
 142                 else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush);
 143         }
 144         else if(pte_newprot(*pte))
 145                 err = protect(mm_id, address, PAGE_SIZE, r, w, x, 1, &flush);
 146
 147         if(err)
 148                 goto kill;
 149
 150         *pte = pte_mkuptodate(*pte);
 151
 152         return;
 153
 154 kill:
 155         printk("Failed to flush page for address 0x%lx\n", address);
 156         force_sig(SIGKILL, current);
 157 }
 158