 8feca0e182
			
		
	
	
	8feca0e182
	
	
	
		
			
			Signed-off-by: Richard Kuo <rkuo@codeaurora.org> Signed-off-by: Linas Vepstas <linas@codeaurora.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			137 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			137 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _ASM_HEXAGON_FUTEX_H
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| #define _ASM_HEXAGON_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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| 
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| /* XXX TODO-- need to add sync barriers! */
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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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| 	"1: %0 = memw_locked(%3);\n" \
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| 	    /* For example: %1 = %4 */ \
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| 	    insn \
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| 	"2: memw_locked(%3,p2) = %1;\n" \
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| 	"   if !p2 jump 1b;\n" \
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| 	"   %1 = #0;\n" \
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| 	"3:\n" \
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| 	".section .fixup,\"ax\"\n" \
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| 	"4: %1 = #%5;\n" \
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| 	"   jump 3b\n" \
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| 	".previous\n" \
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| 	".section __ex_table,\"a\"\n" \
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| 	".long 1b,4b,2b,4b\n" \
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| 	".previous\n" \
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| 	: "=&r" (oldval), "=&r" (ret), "+m" (*uaddr) \
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| 	: "r" (uaddr), "r" (oparg), "i" (-EFAULT) \
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| 	: "p2", "memory")
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| 
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| 
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| static inline int
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| 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("%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("%1 = add(%0,%4)\n", ret, oldval, uaddr,
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| 				  oparg);
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| 		break;
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| 	case FUTEX_OP_OR:
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| 		__futex_atomic_op("%1 = or(%0,%4)\n", ret, oldval, uaddr,
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| 				  oparg);
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| 		break;
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| 	case FUTEX_OP_ANDN:
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| 		__futex_atomic_op("%1 = not(%4); %1 = and(%0,%1)\n", ret,
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| 				  oldval, uaddr, oparg);
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| 		break;
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| 	case FUTEX_OP_XOR:
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| 		__futex_atomic_op("%1 = xor(%0,%4)\n", ret, oldval, uaddr,
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| 				  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:
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| 			ret = (oldval == cmparg);
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| 			break;
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| 		case FUTEX_OP_CMP_NE:
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| 			ret = (oldval != cmparg);
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| 			break;
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| 		case FUTEX_OP_CMP_LT:
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| 			ret = (oldval < cmparg);
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| 			break;
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| 		case FUTEX_OP_CMP_GE:
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| 			ret = (oldval >= cmparg);
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| 			break;
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| 		case FUTEX_OP_CMP_LE:
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| 			ret = (oldval <= cmparg);
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| 			break;
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| 		case FUTEX_OP_CMP_GT:
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| 			ret = (oldval > cmparg);
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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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| 	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(u32 *uval, u32 __user *uaddr, u32 oldval,
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| 			      u32 newval)
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| {
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| 	int prev;
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| 	int ret;
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| 
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| 	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
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| 		return -EFAULT;
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| 
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| 	__asm__ __volatile__ (
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| 	"1: %1 = memw_locked(%3)\n"
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| 	"   {\n"
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| 	"      p2 = cmp.eq(%1,%4)\n"
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| 	"      if !p2.new jump:NT 3f\n"
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| 	"   }\n"
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| 	"2: memw_locked(%3,p2) = %5\n"
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| 	"   if !p2 jump 1b\n"
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| 	"3:\n"
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| 	".section .fixup,\"ax\"\n"
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| 	"4: %0 = #%6\n"
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| 	"   jump 3b\n"
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| 	".previous\n"
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| 	".section __ex_table,\"a\"\n"
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| 	".long 1b,4b,2b,4b\n"
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| 	".previous\n"
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| 	: "+r" (ret), "=&r" (prev), "+m" (*uaddr)
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| 	: "r" (uaddr), "r" (oldval), "r" (newval), "i"(-EFAULT)
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| 	: "p2", "memory");
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| 
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| 	*uval = prev;
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| 	return ret;
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| }
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| 
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| #endif /* __KERNEL__ */
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| #endif /* _ASM_HEXAGON_FUTEX_H */
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