copy_to_user.S 2.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125
  1. /* SPDX-License-Identifier: GPL-2.0-only */
  2. /*
  3. * linux/arch/arm/lib/copy_to_user.S
  4. *
  5. * Author: Nicolas Pitre
  6. * Created: Sep 29, 2005
  7. * Copyright: MontaVista Software, Inc.
  8. */
  9. #include <linux/linkage.h>
  10. #include <asm/assembler.h>
  11. #include <asm/unwind.h>
  12. /*
  13. * Prototype:
  14. *
  15. * size_t arm_copy_to_user(void *to, const void *from, size_t n)
  16. *
  17. * Purpose:
  18. *
  19. * copy a block to user memory from kernel memory
  20. *
  21. * Params:
  22. *
  23. * to = user memory
  24. * from = kernel memory
  25. * n = number of bytes to copy
  26. *
  27. * Return value:
  28. *
  29. * Number of bytes NOT copied.
  30. */
  31. #define LDR1W_SHIFT 0
  32. .macro ldr1w ptr reg abort
  33. W(ldr) \reg, [\ptr], #4
  34. .endm
  35. .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
  36. ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}
  37. .endm
  38. .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  39. ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
  40. .endm
  41. .macro ldr1b ptr reg cond=al abort
  42. ldrb\cond \reg, [\ptr], #1
  43. .endm
  44. #ifdef CONFIG_CPU_USE_DOMAINS
  45. #ifndef CONFIG_THUMB2_KERNEL
  46. #define STR1W_SHIFT 0
  47. #else
  48. #define STR1W_SHIFT 1
  49. #endif
  50. .macro str1w ptr reg abort
  51. strusr \reg, \ptr, 4, abort=\abort
  52. .endm
  53. .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  54. str1w \ptr, \reg1, \abort
  55. str1w \ptr, \reg2, \abort
  56. str1w \ptr, \reg3, \abort
  57. str1w \ptr, \reg4, \abort
  58. str1w \ptr, \reg5, \abort
  59. str1w \ptr, \reg6, \abort
  60. str1w \ptr, \reg7, \abort
  61. str1w \ptr, \reg8, \abort
  62. .endm
  63. #else
  64. #define STR1W_SHIFT 0
  65. .macro str1w ptr reg abort
  66. USERL(\abort, W(str) \reg, [\ptr], #4)
  67. .endm
  68. .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  69. USERL(\abort, stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8})
  70. .endm
  71. #endif /* CONFIG_CPU_USE_DOMAINS */
  72. .macro str1b ptr reg cond=al abort
  73. strusr \reg, \ptr, 1, \cond, abort=\abort
  74. .endm
  75. .macro enter regs:vararg
  76. mov r3, #0
  77. UNWIND( .save {r0, r2, r3, \regs} )
  78. stmdb sp!, {r0, r2, r3, \regs}
  79. .endm
  80. .macro exit regs:vararg
  81. add sp, sp, #8
  82. ldmfd sp!, {r0, \regs}
  83. .endm
  84. .text
  85. ENTRY(__copy_to_user_std)
  86. WEAK(arm_copy_to_user)
  87. #ifdef CONFIG_CPU_SPECTRE
  88. ldr r3, =TASK_SIZE
  89. uaccess_mask_range_ptr r0, r2, r3, ip
  90. #endif
  91. #include "copy_template.S"
  92. ENDPROC(arm_copy_to_user)
  93. ENDPROC(__copy_to_user_std)
  94. .pushsection .text.fixup,"ax"
  95. .align 0
  96. copy_abort_preamble
  97. ldmfd sp!, {r1, r2, r3}
  98. sub r0, r0, r1
  99. rsb r0, r0, r2
  100. copy_abort_end
  101. .popsection