118 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			118 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _ASM_POWERPC_FUTEX_H
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| #define _ASM_POWERPC_FUTEX_H
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| 
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| #ifdef __KERNEL__
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| 
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| #include <linux/futex.h>
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| #include <linux/uaccess.h>
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| #include <asm/errno.h>
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| #include <asm/synch.h>
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| #include <asm/asm-compat.h>
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| 
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| #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
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|   __asm__ __volatile ( \
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| 	LWSYNC_ON_SMP \
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| "1:	lwarx	%0,0,%2\n" \
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| 	insn \
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| 	PPC405_ERR77(0, %2) \
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| "2:	stwcx.	%1,0,%2\n" \
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| 	"bne-	1b\n" \
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| 	"li	%1,0\n" \
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| "3:	.section .fixup,\"ax\"\n" \
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| "4:	li	%1,%3\n" \
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| 	"b	3b\n" \
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| 	".previous\n" \
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| 	".section __ex_table,\"a\"\n" \
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| 	".align 3\n" \
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| 	PPC_LONG "1b,4b,2b,4b\n" \
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| 	".previous" \
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| 	: "=&r" (oldval), "=&r" (ret) \
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| 	: "b" (uaddr), "i" (-EFAULT), "r" (oparg) \
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| 	: "cr0", "memory")
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| 
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| static inline int futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
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| {
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| 	int op = (encoded_op >> 28) & 7;
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| 	int cmp = (encoded_op >> 24) & 15;
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| 	int oparg = (encoded_op << 8) >> 20;
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| 	int cmparg = (encoded_op << 20) >> 20;
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| 	int oldval = 0, ret;
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| 	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
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| 		oparg = 1 << oparg;
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| 
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| 	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
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| 		return -EFAULT;
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| 
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| 	pagefault_disable();
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| 
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| 	switch (op) {
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| 	case FUTEX_OP_SET:
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| 		__futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg);
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| 		break;
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| 	case FUTEX_OP_ADD:
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| 		__futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg);
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| 		break;
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| 	case FUTEX_OP_OR:
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| 		__futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg);
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| 		break;
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| 	case FUTEX_OP_ANDN:
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| 		__futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg);
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| 		break;
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| 	case FUTEX_OP_XOR:
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| 		__futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg);
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| 		break;
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| 	default:
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| 		ret = -ENOSYS;
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| 	}
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| 
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| 	pagefault_enable();
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| 
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| 	if (!ret) {
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| 		switch (cmp) {
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| 		case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
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| 		case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
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| 		case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
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| 		case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
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| 		case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
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| 		case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
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| 		default: ret = -ENOSYS;
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| 		}
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| 	}
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| 	return ret;
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| }
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| 
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| static inline int
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| futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
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| {
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| 	int prev;
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| 
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| 	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
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| 		return -EFAULT;
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| 
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|         __asm__ __volatile__ (
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|         LWSYNC_ON_SMP
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| "1:     lwarx   %0,0,%2         # futex_atomic_cmpxchg_inatomic\n\
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|         cmpw    0,%0,%3\n\
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|         bne-    3f\n"
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|         PPC405_ERR77(0,%2)
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| "2:     stwcx.  %4,0,%2\n\
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|         bne-    1b\n"
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|         ISYNC_ON_SMP
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| "3:	.section .fixup,\"ax\"\n\
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| 4:	li	%0,%5\n\
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| 	b	3b\n\
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| 	.previous\n\
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| 	.section __ex_table,\"a\"\n\
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| 	.align 3\n\
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| 	" PPC_LONG "1b,4b,2b,4b\n\
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| 	.previous" \
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|         : "=&r" (prev), "+m" (*uaddr)
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|         : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)
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|         : "cc", "memory");
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| 
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|         return prev;
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| }
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| 
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| #endif /* __KERNEL__ */
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| #endif /* _ASM_POWERPC_FUTEX_H */
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