[deliverable/linux.git] / arch / x86 / include / asm / futex.h

#ifndef _ASM_X86_FUTEX_H
#define _ASM_X86_FUTEX_H

#ifdef __KERNEL__

#include <linux/futex.h>
#include <linux/uaccess.h>

#include <asm/asm.h>
#include <asm/errno.h>
#include <asm/processor.h>
#include <asm/smap.h>

#define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg)	\
	asm volatile("\t" ASM_STAC "\n"				\
		     "1:\t" insn "\n"				\
		     "2:\t" ASM_CLAC "\n"			\
		     "\t.section .fixup,\"ax\"\n"		\
		     "3:\tmov\t%3, %1\n"			\
		     "\tjmp\t2b\n"				\
		     "\t.previous\n"				\
		     _ASM_EXTABLE(1b, 3b)			\
		     : "=r" (oldval), "=r" (ret), "+m" (*uaddr)	\
		     : "i" (-EFAULT), "0" (oparg), "1" (0))

#define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg)	\
	asm volatile("\t" ASM_STAC "\n"				\
		     "1:\tmovl	%2, %0\n"			\
		     "\tmovl\t%0, %3\n"				\
		     "\t" insn "\n"				\
		     "2:\t" LOCK_PREFIX "cmpxchgl %3, %2\n"	\
		     "\tjnz\t1b\n"				\
		     "3:\t" ASM_CLAC "\n"			\
		     "\t.section .fixup,\"ax\"\n"		\
		     "4:\tmov\t%5, %1\n"			\
		     "\tjmp\t3b\n"				\
		     "\t.previous\n"				\
		     _ASM_EXTABLE(1b, 4b)			\
		     _ASM_EXTABLE(2b, 4b)			\
		     : "=&a" (oldval), "=&r" (ret),		\
		       "+m" (*uaddr), "=&r" (tem)		\
		     : "r" (oparg), "i" (-EFAULT), "1" (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, tem;

	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("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;
	}

	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)
{
	int ret = 0;

	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
		return -EFAULT;

	asm volatile("\t" ASM_STAC "\n"
		     "1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"
		     "2:\t" ASM_CLAC "\n"
		     "\t.section .fixup, \"ax\"\n"
		     "3:\tmov     %3, %0\n"
		     "\tjmp     2b\n"
		     "\t.previous\n"
		     _ASM_EXTABLE(1b, 3b)
		     : "+r" (ret), "=a" (oldval), "+m" (*uaddr)
		     : "i" (-EFAULT), "r" (newval), "1" (oldval)
		     : "memory"
	);

	*uval = oldval;
	return ret;
}

#endif
#endif /* _ASM_X86_FUTEX_H */
Commit	Line	Data
	1	#ifndef _ASM_X86_FUTEX_H
	2	#define _ASM_X86_FUTEX_H
	3
	4	#ifdef __KERNEL__
	5
	6	#include <linux/futex.h>
	7	#include <linux/uaccess.h>
	8
	9	#include <asm/asm.h>
	10	#include <asm/errno.h>
	11	#include <asm/processor.h>
	12	#include <asm/smap.h>
	13
	14	#define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
	15	asm volatile("\t" ASM_STAC "\n" \
	16	"1:\t" insn "\n" \
	17	"2:\t" ASM_CLAC "\n" \
	18	"\t.section .fixup,\"ax\"\n" \
	19	"3:\tmov\t%3, %1\n" \
	20	"\tjmp\t2b\n" \
	21	"\t.previous\n" \
	22	_ASM_EXTABLE(1b, 3b) \
	23	: "=r" (oldval), "=r" (ret), "+m" (*uaddr) \
	24	: "i" (-EFAULT), "0" (oparg), "1" (0))
	25
	26	#define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
	27	asm volatile("\t" ASM_STAC "\n" \
	28	"1:\tmovl %2, %0\n" \
	29	"\tmovl\t%0, %3\n" \
	30	"\t" insn "\n" \
	31	"2:\t" LOCK_PREFIX "cmpxchgl %3, %2\n" \
	32	"\tjnz\t1b\n" \
	33	"3:\t" ASM_CLAC "\n" \
	34	"\t.section .fixup,\"ax\"\n" \
	35	"4:\tmov\t%5, %1\n" \
	36	"\tjmp\t3b\n" \
	37	"\t.previous\n" \
	38	_ASM_EXTABLE(1b, 4b) \
	39	_ASM_EXTABLE(2b, 4b) \
	40	: "=&a" (oldval), "=&r" (ret), \
	41	"+m" (*uaddr), "=&r" (tem) \
	42	: "r" (oparg), "i" (-EFAULT), "1" (0))
	43
	44	static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
	45	{
	46	int op = (encoded_op >> 28) & 7;
	47	int cmp = (encoded_op >> 24) & 15;
	48	int oparg = (encoded_op << 8) >> 20;
	49	int cmparg = (encoded_op << 20) >> 20;
	50	int oldval = 0, ret, tem;
	51
	52	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
	53	oparg = 1 << oparg;
	54
	55	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
	56	return -EFAULT;
	57
	58	pagefault_disable();
	59
	60	switch (op) {
	61	case FUTEX_OP_SET:
	62	__futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
	63	break;
	64	case FUTEX_OP_ADD:
	65	__futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval,
	66	uaddr, oparg);
	67	break;
	68	case FUTEX_OP_OR:
	69	__futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg);
	70	break;
	71	case FUTEX_OP_ANDN:
	72	__futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg);
	73	break;
	74	case FUTEX_OP_XOR:
	75	__futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg);
	76	break;
	77	default:
	78	ret = -ENOSYS;
	79	}
	80
	81	pagefault_enable();
	82
	83	if (!ret) {
	84	switch (cmp) {
	85	case FUTEX_OP_CMP_EQ:
	86	ret = (oldval == cmparg);
	87	break;
	88	case FUTEX_OP_CMP_NE:
	89	ret = (oldval != cmparg);
	90	break;
	91	case FUTEX_OP_CMP_LT:
	92	ret = (oldval < cmparg);
	93	break;
	94	case FUTEX_OP_CMP_GE:
	95	ret = (oldval >= cmparg);
	96	break;
	97	case FUTEX_OP_CMP_LE:
	98	ret = (oldval <= cmparg);
	99	break;
	100	case FUTEX_OP_CMP_GT:
	101	ret = (oldval > cmparg);
	102	break;
	103	default:
	104	ret = -ENOSYS;
	105	}
	106	}
	107	return ret;
	108	}
	109
	110	static inline int futex_atomic_cmpxchg_inatomic(u32 uval, u32 __user uaddr,
	111	u32 oldval, u32 newval)
	112	{
	113	int ret = 0;
	114
	115	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
	116	return -EFAULT;
	117
	118	asm volatile("\t" ASM_STAC "\n"
	119	"1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"
	120	"2:\t" ASM_CLAC "\n"
	121	"\t.section .fixup, \"ax\"\n"
	122	"3:\tmov %3, %0\n"
	123	"\tjmp 2b\n"
	124	"\t.previous\n"
	125	_ASM_EXTABLE(1b, 3b)
	126	: "+r" (ret), "=a" (oldval), "+m" (*uaddr)
	127	: "i" (-EFAULT), "r" (newval), "1" (oldval)
	128	: "memory"
	129	);
	130
	131	*uval = oldval;
	132	return ret;
	133	}
	134
	135	#endif
	136	#endif /* _ASM_X86_FUTEX_H */