copy_from_user.S 2.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125
  1. /* SPDX-License-Identifier: GPL-2.0-only */
  2. /*
  3. * linux/arch/arm/lib/copy_from_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_from_user(void *to, const void *from, size_t n)
  16. *
  17. * Purpose:
  18. *
  19. * copy a block to kernel memory from user memory
  20. *
  21. * Params:
  22. *
  23. * to = kernel memory
  24. * from = user memory
  25. * n = number of bytes to copy
  26. *
  27. * Return value:
  28. *
  29. * Number of bytes NOT copied.
  30. */
  31. #ifdef CONFIG_CPU_USE_DOMAINS
  32. #ifndef CONFIG_THUMB2_KERNEL
  33. #define LDR1W_SHIFT 0
  34. #else
  35. #define LDR1W_SHIFT 1
  36. #endif
  37. .macro ldr1w ptr reg abort
  38. ldrusr \reg, \ptr, 4, abort=\abort
  39. .endm
  40. .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
  41. ldr1w \ptr, \reg1, \abort
  42. ldr1w \ptr, \reg2, \abort
  43. ldr1w \ptr, \reg3, \abort
  44. ldr1w \ptr, \reg4, \abort
  45. .endm
  46. .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  47. ldr4w \ptr, \reg1, \reg2, \reg3, \reg4, \abort
  48. ldr4w \ptr, \reg5, \reg6, \reg7, \reg8, \abort
  49. .endm
  50. #else
  51. #define LDR1W_SHIFT 0
  52. .macro ldr1w ptr reg abort
  53. USERL(\abort, W(ldr) \reg, [\ptr], #4)
  54. .endm
  55. .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
  56. USERL(\abort, ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4})
  57. .endm
  58. .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  59. USERL(\abort, ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8})
  60. .endm
  61. #endif /* CONFIG_CPU_USE_DOMAINS */
  62. .macro ldr1b ptr reg cond=al abort
  63. ldrusr \reg, \ptr, 1, \cond, abort=\abort
  64. .endm
  65. #define STR1W_SHIFT 0
  66. .macro str1w ptr reg abort
  67. W(str) \reg, [\ptr], #4
  68. .endm
  69. .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  70. stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
  71. .endm
  72. .macro str1b ptr reg cond=al abort
  73. strb\cond \reg, [\ptr], #1
  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(arm_copy_from_user)
  86. #ifdef CONFIG_CPU_SPECTRE
  87. ldr r3, =TASK_SIZE
  88. uaccess_mask_range_ptr r1, r2, r3, ip
  89. #endif
  90. #include "copy_template.S"
  91. ENDPROC(arm_copy_from_user)
  92. .pushsection .text.fixup,"ax"
  93. .align 0
  94. copy_abort_preamble
  95. ldmfd sp!, {r1, r2, r3}
  96. sub r0, r0, r1
  97. rsb r0, r0, r2
  98. copy_abort_end
  99. .popsection