futex.h 5.5 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218
  1. /*
  2. * This file is subject to the terms and conditions of the GNU General Public
  3. * License. See the file "COPYING" in the main directory of this archive
  4. * for more details.
  5. *
  6. * Copyright (c) 2006 Ralf Baechle (ralf@linux-mips.org)
  7. */
  8. #ifndef _ASM_FUTEX_H
  9. #define _ASM_FUTEX_H
  10. #ifdef __KERNEL__
  11. #include <linux/futex.h>
  12. #include <linux/uaccess.h>
  13. #include <asm/asm-eva.h>
  14. #include <asm/barrier.h>
  15. #include <asm/compiler.h>
  16. #include <asm/errno.h>
  17. #include <asm/war.h>
  18. #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
  19. { \
  20. if (cpu_has_llsc && R10000_LLSC_WAR) { \
  21. __asm__ __volatile__( \
  22. " .set push \n" \
  23. " .set noat \n" \
  24. " .set arch=r4000 \n" \
  25. "1: ll %1, %4 # __futex_atomic_op \n" \
  26. " .set mips0 \n" \
  27. " " insn " \n" \
  28. " .set arch=r4000 \n" \
  29. "2: sc $1, %2 \n" \
  30. " beqzl $1, 1b \n" \
  31. __WEAK_LLSC_MB \
  32. "3: \n" \
  33. " .insn \n" \
  34. " .set pop \n" \
  35. " .set mips0 \n" \
  36. " .section .fixup,\"ax\" \n" \
  37. "4: li %0, %6 \n" \
  38. " j 3b \n" \
  39. " .previous \n" \
  40. " .section __ex_table,\"a\" \n" \
  41. " "__UA_ADDR "\t1b, 4b \n" \
  42. " "__UA_ADDR "\t2b, 4b \n" \
  43. " .previous \n" \
  44. : "=r" (ret), "=&r" (oldval), \
  45. "=" GCC_OFF_SMALL_ASM() (*uaddr) \
  46. : "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg), \
  47. "i" (-EFAULT) \
  48. : "memory"); \
  49. } else if (cpu_has_llsc) { \
  50. __asm__ __volatile__( \
  51. " .set push \n" \
  52. " .set noat \n" \
  53. " .set "MIPS_ISA_ARCH_LEVEL" \n" \
  54. "1: "user_ll("%1", "%4")" # __futex_atomic_op\n" \
  55. " .set mips0 \n" \
  56. " " insn " \n" \
  57. " .set "MIPS_ISA_ARCH_LEVEL" \n" \
  58. "2: "user_sc("$1", "%2")" \n" \
  59. " beqz $1, 1b \n" \
  60. __WEAK_LLSC_MB \
  61. "3: \n" \
  62. " .insn \n" \
  63. " .set pop \n" \
  64. " .set mips0 \n" \
  65. " .section .fixup,\"ax\" \n" \
  66. "4: li %0, %6 \n" \
  67. " j 3b \n" \
  68. " .previous \n" \
  69. " .section __ex_table,\"a\" \n" \
  70. " "__UA_ADDR "\t1b, 4b \n" \
  71. " "__UA_ADDR "\t2b, 4b \n" \
  72. " .previous \n" \
  73. : "=r" (ret), "=&r" (oldval), \
  74. "=" GCC_OFF_SMALL_ASM() (*uaddr) \
  75. : "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg), \
  76. "i" (-EFAULT) \
  77. : "memory"); \
  78. } else \
  79. ret = -ENOSYS; \
  80. }
  81. static inline int
  82. futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
  83. {
  84. int op = (encoded_op >> 28) & 7;
  85. int cmp = (encoded_op >> 24) & 15;
  86. int oparg = (encoded_op << 8) >> 20;
  87. int cmparg = (encoded_op << 20) >> 20;
  88. int oldval = 0, ret;
  89. if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
  90. oparg = 1 << oparg;
  91. if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32)))
  92. return -EFAULT;
  93. pagefault_disable();
  94. switch (op) {
  95. case FUTEX_OP_SET:
  96. __futex_atomic_op("move $1, %z5", ret, oldval, uaddr, oparg);
  97. break;
  98. case FUTEX_OP_ADD:
  99. __futex_atomic_op("addu $1, %1, %z5",
  100. ret, oldval, uaddr, oparg);
  101. break;
  102. case FUTEX_OP_OR:
  103. __futex_atomic_op("or $1, %1, %z5",
  104. ret, oldval, uaddr, oparg);
  105. break;
  106. case FUTEX_OP_ANDN:
  107. __futex_atomic_op("and $1, %1, %z5",
  108. ret, oldval, uaddr, ~oparg);
  109. break;
  110. case FUTEX_OP_XOR:
  111. __futex_atomic_op("xor $1, %1, %z5",
  112. ret, oldval, uaddr, oparg);
  113. break;
  114. default:
  115. ret = -ENOSYS;
  116. }
  117. pagefault_enable();
  118. if (!ret) {
  119. switch (cmp) {
  120. case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
  121. case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
  122. case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
  123. case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
  124. case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
  125. case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
  126. default: ret = -ENOSYS;
  127. }
  128. }
  129. return ret;
  130. }
  131. static inline int
  132. futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  133. u32 oldval, u32 newval)
  134. {
  135. int ret = 0;
  136. u32 val;
  137. if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
  138. return -EFAULT;
  139. if (cpu_has_llsc && R10000_LLSC_WAR) {
  140. __asm__ __volatile__(
  141. "# futex_atomic_cmpxchg_inatomic \n"
  142. " .set push \n"
  143. " .set noat \n"
  144. " .set arch=r4000 \n"
  145. "1: ll %1, %3 \n"
  146. " bne %1, %z4, 3f \n"
  147. " .set mips0 \n"
  148. " move $1, %z5 \n"
  149. " .set arch=r4000 \n"
  150. "2: sc $1, %2 \n"
  151. " beqzl $1, 1b \n"
  152. __WEAK_LLSC_MB
  153. "3: \n"
  154. " .insn \n"
  155. " .set pop \n"
  156. " .section .fixup,\"ax\" \n"
  157. "4: li %0, %6 \n"
  158. " j 3b \n"
  159. " .previous \n"
  160. " .section __ex_table,\"a\" \n"
  161. " "__UA_ADDR "\t1b, 4b \n"
  162. " "__UA_ADDR "\t2b, 4b \n"
  163. " .previous \n"
  164. : "+r" (ret), "=&r" (val), "=" GCC_OFF_SMALL_ASM() (*uaddr)
  165. : GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
  166. "i" (-EFAULT)
  167. : "memory");
  168. } else if (cpu_has_llsc) {
  169. __asm__ __volatile__(
  170. "# futex_atomic_cmpxchg_inatomic \n"
  171. " .set push \n"
  172. " .set noat \n"
  173. " .set "MIPS_ISA_ARCH_LEVEL" \n"
  174. "1: "user_ll("%1", "%3")" \n"
  175. " bne %1, %z4, 3f \n"
  176. " .set mips0 \n"
  177. " move $1, %z5 \n"
  178. " .set "MIPS_ISA_ARCH_LEVEL" \n"
  179. "2: "user_sc("$1", "%2")" \n"
  180. " beqz $1, 1b \n"
  181. __WEAK_LLSC_MB
  182. "3: \n"
  183. " .insn \n"
  184. " .set pop \n"
  185. " .section .fixup,\"ax\" \n"
  186. "4: li %0, %6 \n"
  187. " j 3b \n"
  188. " .previous \n"
  189. " .section __ex_table,\"a\" \n"
  190. " "__UA_ADDR "\t1b, 4b \n"
  191. " "__UA_ADDR "\t2b, 4b \n"
  192. " .previous \n"
  193. : "+r" (ret), "=&r" (val), "=" GCC_OFF_SMALL_ASM() (*uaddr)
  194. : GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
  195. "i" (-EFAULT)
  196. : "memory");
  197. } else
  198. return -ENOSYS;
  199. *uval = val;
  200. return ret;
  201. }
  202. #endif
  203. #endif /* _ASM_FUTEX_H */