diff options
Diffstat (limited to 'include/asm-s390/futex.h')
| -rw-r--r-- | include/asm-s390/futex.h | 124 |
1 files changed, 120 insertions, 4 deletions
diff --git a/include/asm-s390/futex.h b/include/asm-s390/futex.h index 6a332a9f099c..1802775568b9 100644 --- a/include/asm-s390/futex.h +++ b/include/asm-s390/futex.h @@ -1,6 +1,122 @@ -#ifndef _ASM_FUTEX_H -#define _ASM_FUTEX_H +#ifndef _ASM_S390_FUTEX_H +#define _ASM_S390_FUTEX_H -#include <asm-generic/futex.h> +#ifdef __KERNEL__ -#endif +#include <linux/futex.h> +#include <asm/errno.h> +#include <asm/uaccess.h> + +#ifndef __s390x__ +#define __futex_atomic_fixup \ + ".section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 0b,4b,2b,4b,3b,4b\n" \ + ".previous" +#else /* __s390x__ */ +#define __futex_atomic_fixup \ + ".section __ex_table,\"a\"\n" \ + " .align 8\n" \ + " .quad 0b,4b,2b,4b,3b,4b\n" \ + ".previous" +#endif /* __s390x__ */ + +#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \ + asm volatile(" sacf 256\n" \ + "0: l %1,0(%6)\n" \ + "1: " insn \ + "2: cs %1,%2,0(%6)\n" \ + "3: jl 1b\n" \ + " lhi %0,0\n" \ + "4: sacf 0\n" \ + __futex_atomic_fixup \ + : "=d" (ret), "=&d" (oldval), "=&d" (newval), \ + "=m" (*uaddr) \ + : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \ + "m" (*uaddr) : "cc" ); + +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, newval, ret; + 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_op("lr %2,%5\n", + ret, oldval, newval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("lr %2,%1\nar %2,%5\n", + ret, oldval, newval, uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("lr %2,%1\nor %2,%5\n", + ret, oldval, newval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("lr %2,%1\nnr %2,%5\n", + ret, oldval, newval, uaddr, oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("lr %2,%1\nxr %2,%5\n", + ret, oldval, newval, 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; +} + +static inline int +futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval) +{ + int ret; + + if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int))) + return -EFAULT; + asm volatile(" cs %1,%4,0(%5)\n" + "0: lr %0,%1\n" + "1:\n" +#ifndef __s390x__ + ".section __ex_table,\"a\"\n" + " .align 4\n" + " .long 0b,1b\n" + ".previous" +#else /* __s390x__ */ + ".section __ex_table,\"a\"\n" + " .align 8\n" + " .quad 0b,1b\n" + ".previous" +#endif /* __s390x__ */ + : "=d" (ret), "+d" (oldval), "=m" (*uaddr) + : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr) + : "cc", "memory" ); + return oldval; +} + +#endif /* __KERNEL__ */ +#endif /* _ASM_S390_FUTEX_H */ |