[SPARC64]: Fix fault handling in unaligned trap handler.

We were not calling kernel_mna_trap_fault() correctly.
Instead of being fancy, just return 0 vs. -EFAULT from
the assembler stubs, and handle that return value as
appropriate.

Create an "__retl_efault" stub for assembler exception
table entries and use it where possible.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/kernel/unaligned.c b/arch/sparc64/kernel/unaligned.c
index 9d6be20..70faf63 100644
--- a/arch/sparc64/kernel/unaligned.c
+++ b/arch/sparc64/kernel/unaligned.c
@@ -180,14 +180,14 @@
 	die_if_kernel(str, regs);
 }
 
-extern void do_int_load(unsigned long *dest_reg, int size,
-			unsigned long *saddr, int is_signed, int asi);
+extern int do_int_load(unsigned long *dest_reg, int size,
+		       unsigned long *saddr, int is_signed, int asi);
 	
-extern void __do_int_store(unsigned long *dst_addr, int size,
-			   unsigned long src_val, int asi);
+extern int __do_int_store(unsigned long *dst_addr, int size,
+			  unsigned long src_val, int asi);
 
-static inline void do_int_store(int reg_num, int size, unsigned long *dst_addr,
-				struct pt_regs *regs, int asi, int orig_asi)
+static inline int do_int_store(int reg_num, int size, unsigned long *dst_addr,
+			       struct pt_regs *regs, int asi, int orig_asi)
 {
 	unsigned long zero = 0;
 	unsigned long *src_val_p = &zero;
@@ -219,7 +219,7 @@
 			break;
 		};
 	}
-	__do_int_store(dst_addr, size, src_val, asi);
+	return __do_int_store(dst_addr, size, src_val, asi);
 }
 
 static inline void advance(struct pt_regs *regs)
@@ -242,7 +242,7 @@
 	return !floating_point_load_or_store_p(insn);
 }
 
-void kernel_mna_trap_fault(void)
+static void kernel_mna_trap_fault(void)
 {
 	struct pt_regs *regs = current_thread_info()->kern_una_regs;
 	unsigned int insn = current_thread_info()->kern_una_insn;
@@ -294,7 +294,7 @@
 		kernel_mna_trap_fault();
 	} else {
 		unsigned long addr, *reg_addr;
-		int orig_asi, asi;
+		int orig_asi, asi, err;
 
 		addr = compute_effective_address(regs, insn,
 						 ((insn >> 25) & 0x1f));
@@ -319,9 +319,10 @@
 		switch (dir) {
 		case load:
 			reg_addr = fetch_reg_addr(((insn>>25)&0x1f), regs);
-			do_int_load(reg_addr, size, (unsigned long *) addr,
-				    decode_signedness(insn), asi);
-			if (unlikely(asi != orig_asi)) {
+			err = do_int_load(reg_addr, size,
+					  (unsigned long *) addr,
+					  decode_signedness(insn), asi);
+			if (likely(!err) && unlikely(asi != orig_asi)) {
 				unsigned long val_in = *reg_addr;
 				switch (size) {
 				case 2:
@@ -343,16 +344,19 @@
 			break;
 
 		case store:
-			do_int_store(((insn>>25)&0x1f), size,
-				     (unsigned long *) addr, regs,
-				     asi, orig_asi);
+			err = do_int_store(((insn>>25)&0x1f), size,
+					   (unsigned long *) addr, regs,
+					   asi, orig_asi);
 			break;
 
 		default:
 			panic("Impossible kernel unaligned trap.");
 			/* Not reached... */
 		}
-		advance(regs);
+		if (unlikely(err))
+			kernel_mna_trap_fault();
+		else
+			advance(regs);
 	}
 }