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/arch/mn10300/mm/mmu-context.c

https://bitbucket.org/cresqo/cm7-p500-kernel
C | 81 lines | 45 code | 13 blank | 23 comment | 9 complexity | 2e6a8cf5f6164d1c05b36f3fc86288a8 MD5 | raw file
Possible License(s): LGPL-2.0, AGPL-1.0, GPL-2.0 
    

  1. /* MN10300 MMU context allocation and management
    2. 

  2.  *
    3. 

  3.  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
    4. 

  4.  * Written by David Howells (dhowells@redhat.com)
    5. 

  5.  *
    6. 

  6.  * This program is free software; you can redistribute it and/or
    7. 

  7.  * modify it under the terms of the GNU General Public Licence
    8. 

  8.  * as published by the Free Software Foundation; either version
    9. 

  9.  * 2 of the Licence, or (at your option) any later version.
    10. 

  10.  */
    11. 

  11. #include <linux/sched.h>
    12. 

  12. #include <linux/mm.h>
    13. 

  13. #include <asm/mmu_context.h>
    14. 

  14. #include <asm/tlbflush.h>
    15. 

  15. 

  16. /*
    17. 

  17.  * list of the MMU contexts last allocated on each CPU
    18. 

  18.  */
    19. 

  19. unsigned long mmu_context_cache[NR_CPUS] = {
    20. 

  20. 	[0 ... NR_CPUS - 1] = MMU_CONTEXT_FIRST_VERSION * 2 - 1,
    21. 

  21. };
    22. 

  22. 

  23. /*
    24. 

  24.  * flush the specified TLB entry
    25. 

  25.  */
    26. 

  26. void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
    27. 

  27. {
    28. 

  28. 	unsigned long pteu, cnx, flags;
    29. 

  29. 

  30. 	addr &= PAGE_MASK;
    31. 

  31. 

  32. 	/* make sure the context doesn't migrate and defend against
    33. 

  33. 	 * interference from vmalloc'd regions */
    34. 

  34. 	local_irq_save(flags);
    35. 

  35. 

  36. 	cnx = mm_context(vma->vm_mm);
    37. 

  37. 

  38. 	if (cnx != MMU_NO_CONTEXT) {
    39. 

  39. 		pteu = addr | (cnx & 0x000000ffUL);
    40. 

  40. 		IPTEU = pteu;
    41. 

  41. 		DPTEU = pteu;
    42. 

  42. 		if (IPTEL & xPTEL_V)
    43. 

  43. 			IPTEL = 0;
    44. 

  44. 		if (DPTEL & xPTEL_V)
    45. 

  45. 			DPTEL = 0;
    46. 

  46. 	}
    47. 

  47. 

  48. 	local_irq_restore(flags);
    49. 

  49. }
    50. 

  50. 

  51. /*
    52. 

  52.  * preemptively set a TLB entry
    53. 

  53.  */
    54. 

  54. void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
    55. 

  55. {
    56. 

  56. 	unsigned long pteu, ptel, cnx, flags;
    57. 

  57. 	pte_t pte = *ptep;
    58. 

  58. 

  59. 	addr &= PAGE_MASK;
    60. 

  60. 	ptel = pte_val(pte) & ~(xPTEL_UNUSED1 | xPTEL_UNUSED2);
    61. 

  61. 

  62. 	/* make sure the context doesn't migrate and defend against
    63. 

  63. 	 * interference from vmalloc'd regions */
    64. 

  64. 	local_irq_save(flags);
    65. 

  65. 

  66. 	cnx = mm_context(vma->vm_mm);
    67. 

  67. 

  68. 	if (cnx != MMU_NO_CONTEXT) {
    69. 

  69. 		pteu = addr | (cnx & 0x000000ffUL);
    70. 

  70. 		if (!(pte_val(pte) & _PAGE_NX)) {
    71. 

  71. 			IPTEU = pteu;
    72. 

  72. 			if (IPTEL & xPTEL_V)
    73. 

  73. 				IPTEL = ptel;
    74. 

  74. 		}
    75. 

  75. 		DPTEU = pteu;
    76. 

  76. 		if (DPTEL & xPTEL_V)
    77. 

  77. 			DPTEL = ptel;
    78. 

  78. 	}
    79. 

  79. 

  80. 	local_irq_restore(flags);
    81. 

  81. }
    82. 

  82.