| Michal Simek | fd3db0a | 2009-10-19 11:58:44 +0200 | [diff] [blame] | 1 | #ifndef _ASM_MICROBLAZE_FUTEX_H |
| 2 | #define _ASM_MICROBLAZE_FUTEX_H |
| 3 | |
| 4 | #ifdef __KERNEL__ |
| 5 | |
| 6 | #include <linux/futex.h> |
| 7 | #include <linux/uaccess.h> |
| 8 | #include <asm/errno.h> |
| 9 | |
| 10 | #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ |
| 11 | ({ \ |
| 12 | __asm__ __volatile__ ( \ |
| 13 | "1: lwx %0, %2, r0; " \ |
| 14 | insn \ |
| 15 | "2: swx %1, %2, r0; \ |
| 16 | addic %1, r0, 0; \ |
| 17 | bnei %1, 1b; \ |
| 18 | 3: \ |
| 19 | .section .fixup,\"ax\"; \ |
| 20 | 4: brid 3b; \ |
| 21 | addik %1, r0, %3; \ |
| 22 | .previous; \ |
| 23 | .section __ex_table,\"a\"; \ |
| 24 | .word 1b,4b,2b,4b; \ |
| 25 | .previous;" \ |
| 26 | : "=&r" (oldval), "=&r" (ret) \ |
| 27 | : "b" (uaddr), "i" (-EFAULT), "r" (oparg) \ |
| 28 | ); \ |
| 29 | }) |
| 30 | |
| 31 | static inline int |
| 32 | futex_atomic_op_inuser(int encoded_op, int __user *uaddr) |
| 33 | { |
| 34 | int op = (encoded_op >> 28) & 7; |
| 35 | int cmp = (encoded_op >> 24) & 15; |
| 36 | int oparg = (encoded_op << 8) >> 20; |
| 37 | int cmparg = (encoded_op << 20) >> 20; |
| 38 | int oldval = 0, ret; |
| 39 | if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) |
| 40 | oparg = 1 << oparg; |
| 41 | |
| 42 | if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int))) |
| 43 | return -EFAULT; |
| 44 | |
| 45 | pagefault_disable(); |
| 46 | |
| 47 | switch (op) { |
| 48 | case FUTEX_OP_SET: |
| 49 | __futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg); |
| 50 | break; |
| 51 | case FUTEX_OP_ADD: |
| 52 | __futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg); |
| 53 | break; |
| 54 | case FUTEX_OP_OR: |
| 55 | __futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg); |
| 56 | break; |
| 57 | case FUTEX_OP_ANDN: |
| Michal Simek | 4bb30ba | 2010-04-06 18:51:37 +0200 | [diff] [blame] | 58 | __futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg); |
| Michal Simek | fd3db0a | 2009-10-19 11:58:44 +0200 | [diff] [blame] | 59 | break; |
| 60 | case FUTEX_OP_XOR: |
| 61 | __futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg); |
| 62 | break; |
| 63 | default: |
| 64 | ret = -ENOSYS; |
| 65 | } |
| 66 | |
| 67 | pagefault_enable(); |
| 68 | |
| 69 | if (!ret) { |
| 70 | switch (cmp) { |
| 71 | case FUTEX_OP_CMP_EQ: |
| 72 | ret = (oldval == cmparg); |
| 73 | break; |
| 74 | case FUTEX_OP_CMP_NE: |
| 75 | ret = (oldval != cmparg); |
| 76 | break; |
| 77 | case FUTEX_OP_CMP_LT: |
| 78 | ret = (oldval < cmparg); |
| 79 | break; |
| 80 | case FUTEX_OP_CMP_GE: |
| 81 | ret = (oldval >= cmparg); |
| 82 | break; |
| 83 | case FUTEX_OP_CMP_LE: |
| 84 | ret = (oldval <= cmparg); |
| 85 | break; |
| 86 | case FUTEX_OP_CMP_GT: |
| 87 | ret = (oldval > cmparg); |
| 88 | break; |
| 89 | default: |
| 90 | ret = -ENOSYS; |
| 91 | } |
| 92 | } |
| 93 | return ret; |
| 94 | } |
| 95 | |
| 96 | static inline int |
| 97 | futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval) |
| 98 | { |
| 99 | int prev, cmp; |
| 100 | |
| 101 | if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int))) |
| 102 | return -EFAULT; |
| 103 | |
| 104 | __asm__ __volatile__ ("1: lwx %0, %2, r0; \ |
| 105 | cmp %1, %0, %3; \ |
| 106 | beqi %1, 3f; \ |
| 107 | 2: swx %4, %2, r0; \ |
| 108 | addic %1, r0, 0; \ |
| 109 | bnei %1, 1b; \ |
| 110 | 3: \ |
| 111 | .section .fixup,\"ax\"; \ |
| 112 | 4: brid 3b; \ |
| 113 | addik %0, r0, %5; \ |
| 114 | .previous; \ |
| 115 | .section __ex_table,\"a\"; \ |
| 116 | .word 1b,4b,2b,4b; \ |
| 117 | .previous;" \ |
| 118 | : "=&r" (prev), "=&r"(cmp) \ |
| 119 | : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)); |
| 120 | |
| 121 | return prev; |
| 122 | } |
| 123 | |
| 124 | #endif /* __KERNEL__ */ |
| 125 | |
| 126 | #endif |