arch/um/kernel/skas/tlb.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/stddef.h"
   7 #include "linux/sched.h"
   8 #include "linux/mm.h"
   9 #include "asm/page.h"
  10 #include "asm/pgtable.h"
  11 #include "asm/mmu.h"
  12 #include "user_util.h"
  13 #include "mem_user.h"
  14 #include "skas.h"
  15 #include "os.h"
  16
  17 static void fix_range(struct mm_struct *mm, unsigned long start_addr,
  18                       unsigned long end_addr, int force)
  19 {
  20         pgd_t *npgd;
  21         pmd_t *npmd;
  22         pte_t *npte;
  23         unsigned long addr;
  24         int r, w, x, err, fd;
  25
  26         if(mm == NULL) return;
  27         fd = mm->context.skas.mm_fd;
  28         for(addr = start_addr; addr < end_addr;){
  29                 npgd = pgd_offset(mm, addr);
  30                 npmd = pmd_offset(npgd, addr);
  31                 if(pmd_present(*npmd)){
  32                         npte = pte_offset_kernel(npmd, addr);
  33                         r = pte_read(*npte);
  34                         w = pte_write(*npte);
  35                         x = pte_exec(*npte);
  36                         if(!pte_dirty(*npte)) w = 0;
  37                         if(!pte_young(*npte)){
  38                                 r = 0;
  39                                 w = 0;
  40                         }
  41                         if(force || pte_newpage(*npte)){
  42                                 err = unmap(fd, (void *) addr, PAGE_SIZE);
  43                                 if(err < 0)
  44                                         panic("munmap failed, errno = %d\n",
  45                                               -err);
  46                                 if(pte_present(*npte))
  47                                         map(fd, addr,
  48                                             pte_val(*npte) & PAGE_MASK,
  49                                             PAGE_SIZE, r, w, x);
  50                         }
  51                         else if(pte_newprot(*npte)){
  52                                 protect(fd, addr, PAGE_SIZE, r, w, x, 1);
  53                         }
  54                         *npte = pte_mkuptodate(*npte);
  55                         addr += PAGE_SIZE;
  56                 }
  57                 else {
  58                         if(force || pmd_newpage(*npmd)){
  59                                 err = unmap(fd, (void *) addr, PMD_SIZE);
  60                                 if(err < 0)
  61                                         panic("munmap failed, errno = %d\n",
  62                                               -err);
  63                                 pmd_mkuptodate(*npmd);
  64                         }
  65                         addr += PMD_SIZE;
  66                 }
  67         }
  68 }
  69
  70 void flush_tlb_kernel_range_skas(unsigned long start, unsigned long end)
  71 {
  72         struct mm_struct *mm;
  73         pgd_t *pgd;
  74         pmd_t *pmd;
  75         pte_t *pte;
  76         unsigned long addr;
  77         int updated = 0, err;
  78
  79         mm = &init_mm;
  80         for(addr = start_vm; addr < end_vm;){
  81                 pgd = pgd_offset(mm, addr);
  82                 pmd = pmd_offset(pgd, addr);
  83                 if(pmd_present(*pmd)){
  84                         pte = pte_offset_kernel(pmd, addr);
  85                         if(!pte_present(*pte) || pte_newpage(*pte)){
  86                                 updated = 1;
  87                                 err = os_unmap_memory((void *) addr,
  88                                                       PAGE_SIZE);
  89                                 if(err < 0)
  90                                         panic("munmap failed, errno = %d\n",
  91                                               -err);
  92                                 if(pte_present(*pte))
  93                                         map_memory(addr,
  94                                                    pte_val(*pte) & PAGE_MASK,
  95                                                    PAGE_SIZE, 1, 1, 1);
  96                         }
  97                         else if(pte_newprot(*pte)){
  98                                 updated = 1;
  99                                 protect_memory(addr, PAGE_SIZE, 1, 1, 1, 1);
 100                         }
 101                         addr += PAGE_SIZE;
 102                 }
 103                 else {
 104                         if(pmd_newpage(*pmd)){
 105                                 updated = 1;
 106                                 err = os_unmap_memory((void *) addr, PMD_SIZE);
 107                                 if(err < 0)
 108                                         panic("munmap failed, errno = %d\n",
 109                                               -err);
 110                         }
 111                         addr += PMD_SIZE;
 112                 }
 113         }
 114 }
 115
 116 void flush_tlb_kernel_vm_skas(void)
 117 {
 118         flush_tlb_kernel_range_skas(start_vm, end_vm);
 119 }
 120
 121 void __flush_tlb_one_skas(unsigned long addr)
 122 {
 123         flush_tlb_kernel_range_skas(addr, addr + PAGE_SIZE);
 124 }
 125
 126 void flush_tlb_range_skas(struct vm_area_struct *vma, unsigned long start,
 127                      unsigned long end)
 128 {
 129         if(vma->vm_mm == NULL)
 130                 flush_tlb_kernel_range_skas(start, end);
 131         else fix_range(vma->vm_mm, start, end, 0);
 132 }
 133
 134 void flush_tlb_mm_skas(struct mm_struct *mm)
 135 {
 136         flush_tlb_kernel_vm_skas();
 137         fix_range(mm, 0, host_task_size, 0);
 138 }
 139
 140 void force_flush_all_skas(void)
 141 {
 142         fix_range(current->mm, 0, host_task_size, 1);
 143 }
 144
 145 /*
 146  * Overrides for Emacs so that we follow Linus's tabbing style.
 147  * Emacs will notice this stuff at the end of the file and automatically
 148  * adjust the settings for this buffer only.  This must remain at the end
 149  * of the file.
 150  * ---------------------------------------------------------------------------
 151  * Local variables:
 152  * c-file-style: "linux"
 153  * End:
 154  */