arch/um/kernel/tt/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/kernel.h"
   9 #include "linux/sched.h"
  10 #include "linux/mm.h"
  11 #include "asm/page.h"
  12 #include "asm/pgtable.h"
  13 #include "asm/uaccess.h"
  14 #include "asm/tlbflush.h"
  15 #include "user_util.h"
  16 #include "mem_user.h"
  17 #include "os.h"
  18 #include "tlb.h"
  19
  20 static int do_ops(union mm_context *mmu, struct host_vm_op *ops, int last,
  21                     int finished, void **flush)
  22 {
  23         struct host_vm_op *op;
  24         int i, ret=0;
  25
  26         for(i = 0; i <= last && !ret; i++){
  27                 op = &ops[i];
  28                 switch(op->type){
  29                 case MMAP:
  30                         ret = os_map_memory((void *) op->u.mmap.addr,
  31                                             op->u.mmap.fd, op->u.mmap.offset,
  32                                             op->u.mmap.len, op->u.mmap.r,
  33                                             op->u.mmap.w, op->u.mmap.x);
  34                         break;
  35                 case MUNMAP:
  36                         ret = os_unmap_memory((void *) op->u.munmap.addr,
  37                                               op->u.munmap.len);
  38                         break;
  39                 case MPROTECT:
  40                         ret = protect_memory(op->u.mprotect.addr,
  41                                              op->u.munmap.len,
  42                                              op->u.mprotect.r,
  43                                              op->u.mprotect.w,
  44                                              op->u.mprotect.x, 1);
  45                         protect_memory(op->u.mprotect.addr, op->u.munmap.len,
  46                                        op->u.mprotect.r, op->u.mprotect.w,
  47                                        op->u.mprotect.x, 1);
  48                         break;
  49                 default:
  50                         printk("Unknown op type %d in do_ops\n", op->type);
  51                         break;
  52                 }
  53         }
  54
  55         return ret;
  56 }
  57
  58 static void fix_range(struct mm_struct *mm, unsigned long start_addr,
  59                       unsigned long end_addr, int force)
  60 {
  61         if((current->thread.mode.tt.extern_pid != -1) &&
  62            (current->thread.mode.tt.extern_pid != os_getpid()))
  63                 panic("fix_range fixing wrong address space, current = 0x%p",
  64                       current);
  65
  66         fix_range_common(mm, start_addr, end_addr, force, do_ops);
  67 }
  68
  69 atomic_t vmchange_seq = ATOMIC_INIT(1);
  70
  71 void flush_tlb_kernel_range_tt(unsigned long start, unsigned long end)
  72 {
  73         if(flush_tlb_kernel_range_common(start, end))
  74                 atomic_inc(&vmchange_seq);
  75 }
  76
  77 static void protect_vm_page(unsigned long addr, int w, int must_succeed)
  78 {
  79         int err;
  80
  81         err = protect_memory(addr, PAGE_SIZE, 1, w, 1, must_succeed);
  82         if(err == 0) return;
  83         else if((err == -EFAULT) || (err == -ENOMEM)){
  84                 flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
  85                 protect_vm_page(addr, w, 1);
  86         }
  87         else panic("protect_vm_page : protect failed, errno = %d\n", err);
  88 }
  89
  90 void mprotect_kernel_vm(int w)
  91 {
  92         struct mm_struct *mm;
  93         pgd_t *pgd;
  94         pud_t *pud;
  95         pmd_t *pmd;
  96         pte_t *pte;
  97         unsigned long addr;
  98
  99         mm = &init_mm;
 100         for(addr = start_vm; addr < end_vm;){
 101                 pgd = pgd_offset(mm, addr);
 102                 pud = pud_offset(pgd, addr);
 103                 pmd = pmd_offset(pud, addr);
 104                 if(pmd_present(*pmd)){
 105                         pte = pte_offset_kernel(pmd, addr);
 106                         if(pte_present(*pte)) protect_vm_page(addr, w, 0);
 107                         addr += PAGE_SIZE;
 108                 }
 109                 else addr += PMD_SIZE;
 110         }
 111 }
 112
 113 void flush_tlb_kernel_vm_tt(void)
 114 {
 115         flush_tlb_kernel_range(start_vm, end_vm);
 116 }
 117
 118 void __flush_tlb_one_tt(unsigned long addr)
 119 {
 120         flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
 121 }
 122
 123 void flush_tlb_range_tt(struct vm_area_struct *vma, unsigned long start,
 124                      unsigned long end)
 125 {
 126         if(vma->vm_mm != current->mm) return;
 127
 128         /* Assumes that the range start ... end is entirely within
 129          * either process memory or kernel vm
 130          */
 131         if((start >= start_vm) && (start < end_vm)){
 132                 if(flush_tlb_kernel_range_common(start, end))
 133                         atomic_inc(&vmchange_seq);
 134         }
 135         else fix_range(vma->vm_mm, start, end, 0);
 136 }
 137
 138 void flush_tlb_mm_tt(struct mm_struct *mm)
 139 {
 140         unsigned long seq;
 141
 142         if(mm != current->mm) return;
 143
 144         fix_range(mm, 0, STACK_TOP, 0);
 145
 146         seq = atomic_read(&vmchange_seq);
 147         if(current->thread.mode.tt.vm_seq == seq)
 148                 return;
 149         current->thread.mode.tt.vm_seq = seq;
 150         flush_tlb_kernel_range_common(start_vm, end_vm);
 151 }
 152
 153 void force_flush_all_tt(void)
 154 {
 155         fix_range(current->mm, 0, STACK_TOP, 1);
 156         flush_tlb_kernel_range_common(start_vm, end_vm);
 157 }