diff options
Diffstat (limited to 'kernel/arch/ia64/include/asm/futex.h')
| -rw-r--r-- | kernel/arch/ia64/include/asm/futex.h | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/kernel/arch/ia64/include/asm/futex.h b/kernel/arch/ia64/include/asm/futex.h new file mode 100644 index 000000000..76acbcd5c --- /dev/null +++ b/kernel/arch/ia64/include/asm/futex.h @@ -0,0 +1,126 @@ +#ifndef _ASM_FUTEX_H +#define _ASM_FUTEX_H + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/errno.h> + +#define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \ +do { \ + register unsigned long r8 __asm ("r8") = 0; \ + __asm__ __volatile__( \ + " mf;; \n" \ + "[1:] " insn ";; \n" \ + " .xdata4 \"__ex_table\", 1b-., 2f-. \n" \ + "[2:]" \ + : "+r" (r8), "=r" (oldval) \ + : "r" (uaddr), "r" (oparg) \ + : "memory"); \ + ret = r8; \ +} while (0) + +#define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \ +do { \ + register unsigned long r8 __asm ("r8") = 0; \ + int val, newval; \ + do { \ + __asm__ __volatile__( \ + " mf;; \n" \ + "[1:] ld4 %3=[%4];; \n" \ + " mov %2=%3 \n" \ + insn ";; \n" \ + " mov ar.ccv=%2;; \n" \ + "[2:] cmpxchg4.acq %1=[%4],%3,ar.ccv;; \n" \ + " .xdata4 \"__ex_table\", 1b-., 3f-.\n" \ + " .xdata4 \"__ex_table\", 2b-., 3f-.\n" \ + "[3:]" \ + : "+r" (r8), "=r" (val), "=&r" (oldval), \ + "=&r" (newval) \ + : "r" (uaddr), "r" (oparg) \ + : "memory"); \ + if (unlikely (r8)) \ + break; \ + } while (unlikely (val != oldval)); \ + ret = r8; \ +} while (0) + +static inline int +futex_atomic_op_inuser (int encoded_op, u32 __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; + if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) + oparg = 1 << oparg; + + if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + pagefault_disable(); + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op1("xchg4 %1=[%2],%3", ret, oldval, uaddr, + oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op2("add %3=%3,%5", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op2("or %3=%3,%5", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op2("and %3=%3,%5", ret, oldval, uaddr, + ~oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op2("xor %3=%3,%5", ret, oldval, uaddr, oparg); + break; + default: + ret = -ENOSYS; + } + + pagefault_enable(); + + 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(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + { + register unsigned long r8 __asm ("r8") = 0; + unsigned long prev; + __asm__ __volatile__( + " mf;; \n" + " mov ar.ccv=%4;; \n" + "[1:] cmpxchg4.acq %1=[%2],%3,ar.ccv \n" + " .xdata4 \"__ex_table\", 1b-., 2f-. \n" + "[2:]" + : "+r" (r8), "=&r" (prev) + : "r" (uaddr), "r" (newval), + "rO" ((long) (unsigned) oldval) + : "memory"); + *uval = prev; + return r8; + } +} + +#endif /* _ASM_FUTEX_H */ |