diff options
| author | Len Brown <len.brown@intel.com> | 2005-09-08 01:45:47 -0400 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2005-09-08 01:45:47 -0400 |
| commit | 64e47488c913ac704d465a6af86a26786d1412a5 (patch) | |
| tree | d3b0148592963dcde26e4bb35ddfec8b1eaf8e23 /include/asm-x86_64/futex.h | |
| parent | 4a35a46bf1cda4737c428380d1db5d15e2590d18 (diff) | |
| parent | caf39e87cc1182f7dae84eefc43ca14d54c78ef9 (diff) | |
Merge linux-2.6 with linux-acpi-2.6
Diffstat (limited to 'include/asm-x86_64/futex.h')
| -rw-r--r-- | include/asm-x86_64/futex.h | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/include/asm-x86_64/futex.h b/include/asm-x86_64/futex.h new file mode 100644 index 000000000000..8602c09bf89e --- /dev/null +++ b/include/asm-x86_64/futex.h @@ -0,0 +1,98 @@ +#ifndef _ASM_FUTEX_H +#define _ASM_FUTEX_H + +#ifdef __KERNEL__ + +#include <linux/futex.h> +#include <asm/errno.h> +#include <asm/system.h> +#include <asm/uaccess.h> + +#define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \ + __asm__ __volatile ( \ +"1: " insn "\n" \ +"2: .section .fixup,\"ax\"\n\ +3: mov %3, %1\n\ + jmp 2b\n\ + .previous\n\ + .section __ex_table,\"a\"\n\ + .align 8\n\ + .quad 1b,3b\n\ + .previous" \ + : "=r" (oldval), "=r" (ret), "=m" (*uaddr) \ + : "i" (-EFAULT), "m" (*uaddr), "0" (oparg), "1" (0)) + +#define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \ + __asm__ __volatile ( \ +"1: movl %2, %0\n\ + movl %0, %3\n" \ + insn "\n" \ +"2: " LOCK_PREFIX "cmpxchgl %3, %2\n\ + jnz 1b\n\ +3: .section .fixup,\"ax\"\n\ +4: mov %5, %1\n\ + jmp 3b\n\ + .previous\n\ + .section __ex_table,\"a\"\n\ + .align 8\n\ + .quad 1b,4b,2b,4b\n\ + .previous" \ + : "=&a" (oldval), "=&r" (ret), "=m" (*uaddr), \ + "=&r" (tem) \ + : "r" (oparg), "i" (-EFAULT), "m" (*uaddr), "1" (0)) + +static inline int +futex_atomic_op_inuser (int encoded_op, int __user *uaddr) +{ + int op = (encoded_op >> 28) & 7; + int cmp = (encoded_op >> 24) & 15; + int oparg = (encoded_op << 8) >> 20; + int cmparg = (encoded_op << 20) >> 20; + int oldval = 0, ret, tem; + if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) + oparg = 1 << oparg; + + if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int))) + return -EFAULT; + + inc_preempt_count(); + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval, + uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg); + break; + default: + ret = -ENOSYS; + } + + dec_preempt_count(); + + if (!ret) { + switch (cmp) { + case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break; + case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break; + case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break; + case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break; + case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break; + case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break; + default: ret = -ENOSYS; + } + } + return ret; +} + +#endif +#endif |