hypercall.S 3.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106
  1. /******************************************************************************
  2. * hypercall.S
  3. *
  4. * Xen hypercall wrappers
  5. *
  6. * Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Citrix, 2012
  7. *
  8. * This program is free software; you can redistribute it and/or
  9. * modify it under the terms of the GNU General Public License version 2
  10. * as published by the Free Software Foundation; or, when distributed
  11. * separately from the Linux kernel or incorporated into other
  12. * software packages, subject to the following license:
  13. *
  14. * Permission is hereby granted, free of charge, to any person obtaining a copy
  15. * of this source file (the "Software"), to deal in the Software without
  16. * restriction, including without limitation the rights to use, copy, modify,
  17. * merge, publish, distribute, sublicense, and/or sell copies of the Software,
  18. * and to permit persons to whom the Software is furnished to do so, subject to
  19. * the following conditions:
  20. *
  21. * The above copyright notice and this permission notice shall be included in
  22. * all copies or substantial portions of the Software.
  23. *
  24. * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  25. * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  26. * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  27. * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  28. * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  29. * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  30. * IN THE SOFTWARE.
  31. */
  32. /*
  33. * The Xen hypercall calling convention is very similar to the ARM
  34. * procedure calling convention: the first paramter is passed in r0, the
  35. * second in r1, the third in r2 and the fourth in r3. Considering that
  36. * Xen hypercalls have 5 arguments at most, the fifth paramter is passed
  37. * in r4, differently from the procedure calling convention of using the
  38. * stack for that case.
  39. *
  40. * The hypercall number is passed in r12.
  41. *
  42. * The return value is in r0.
  43. *
  44. * The hvc ISS is required to be 0xEA1, that is the Xen specific ARM
  45. * hypercall tag.
  46. */
  47. #include <linux/linkage.h>
  48. #include <asm/assembler.h>
  49. #include <xen/interface/xen.h>
  50. /* HVC 0xEA1 */
  51. #ifdef CONFIG_THUMB2_KERNEL
  52. #define xen_hvc .word 0xf7e08ea1
  53. #else
  54. #define xen_hvc .word 0xe140ea71
  55. #endif
  56. #define HYPERCALL_SIMPLE(hypercall) \
  57. ENTRY(HYPERVISOR_##hypercall) \
  58. mov r12, #__HYPERVISOR_##hypercall; \
  59. xen_hvc; \
  60. mov pc, lr; \
  61. ENDPROC(HYPERVISOR_##hypercall)
  62. #define HYPERCALL0 HYPERCALL_SIMPLE
  63. #define HYPERCALL1 HYPERCALL_SIMPLE
  64. #define HYPERCALL2 HYPERCALL_SIMPLE
  65. #define HYPERCALL3 HYPERCALL_SIMPLE
  66. #define HYPERCALL4 HYPERCALL_SIMPLE
  67. #define HYPERCALL5(hypercall) \
  68. ENTRY(HYPERVISOR_##hypercall) \
  69. stmdb sp!, {r4} \
  70. ldr r4, [sp, #4] \
  71. mov r12, #__HYPERVISOR_##hypercall; \
  72. xen_hvc \
  73. ldm sp!, {r4} \
  74. mov pc, lr \
  75. ENDPROC(HYPERVISOR_##hypercall)
  76. .text
  77. HYPERCALL2(xen_version);
  78. HYPERCALL3(console_io);
  79. HYPERCALL3(grant_table_op);
  80. HYPERCALL2(sched_op);
  81. HYPERCALL2(event_channel_op);
  82. HYPERCALL2(hvm_op);
  83. HYPERCALL2(memory_op);
  84. HYPERCALL2(physdev_op);
  85. ENTRY(privcmd_call)
  86. stmdb sp!, {r4}
  87. mov r12, r0
  88. mov r0, r1
  89. mov r1, r2
  90. mov r2, r3
  91. ldr r3, [sp, #8]
  92. ldr r4, [sp, #4]
  93. xen_hvc
  94. ldm sp!, {r4}
  95. mov pc, lr
  96. ENDPROC(privcmd_call);