putuser.S 1.6 KB

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  1. /*
  2. * linux/arch/arm/lib/putuser.S
  3. *
  4. * Copyright (C) 2001 Russell King
  5. *
  6. * This program is free software; you can redistribute it and/or modify
  7. * it under the terms of the GNU General Public License version 2 as
  8. * published by the Free Software Foundation.
  9. *
  10. * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
  11. *
  12. * These functions have a non-standard call interface to make
  13. * them more efficient, especially as they return an error
  14. * value in addition to the "real" return value.
  15. *
  16. * __put_user_X
  17. *
  18. * Inputs: r0 contains the address
  19. * r2, r3 contains the value
  20. * Outputs: r0 is the error code
  21. * lr corrupted
  22. *
  23. * No other registers must be altered. (see include/asm-arm/uaccess.h
  24. * for specific ASM register usage).
  25. *
  26. * Note that ADDR_LIMIT is either 0 or 0xc0000000
  27. * Note also that it is intended that __put_user_bad is not global.
  28. */
  29. #include <asm/asm-offsets.h>
  30. #include <asm/thread_info.h>
  31. #include <asm/errno.h>
  32. .global __put_user_1
  33. __put_user_1:
  34. 1: strbt r2, [r0]
  35. mov r0, #0
  36. mov pc, lr
  37. .global __put_user_2
  38. __put_user_2:
  39. mov ip, r2, lsr #8
  40. #ifndef __ARMEB__
  41. 2: strbt r2, [r0], #1
  42. 3: strbt ip, [r0]
  43. #else
  44. 2: strbt ip, [r0], #1
  45. 3: strbt r2, [r0]
  46. #endif
  47. mov r0, #0
  48. mov pc, lr
  49. .global __put_user_4
  50. __put_user_4:
  51. 4: strt r2, [r0]
  52. mov r0, #0
  53. mov pc, lr
  54. .global __put_user_8
  55. __put_user_8:
  56. 5: strt r2, [r0], #4
  57. 6: strt r3, [r0]
  58. mov r0, #0
  59. mov pc, lr
  60. __put_user_bad:
  61. mov r0, #-EFAULT
  62. mov pc, lr
  63. .section __ex_table, "a"
  64. .long 1b, __put_user_bad
  65. .long 2b, __put_user_bad
  66. .long 3b, __put_user_bad
  67. .long 4b, __put_user_bad
  68. .long 5b, __put_user_bad
  69. .long 6b, __put_user_bad
  70. .previous