[SPARC64]: Convert to use generic exception table support.

The funny "range" exception table entries we had were only
used by the compat layer socketcall assembly, and it wasn't
even needed there.

For free we now get proper exception table sorting and fast
binary searching.

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 4 insertions, 88 deletions

diff --git a/arch/sparc64/mm/Makefile b/arch/sparc64/mm/Makefile
index cda87333a77b..9d0960e69f48 100644
--- a/arch/sparc64/mm/Makefile
+++ b/arch/sparc64/mm/Makefile
@@ -5,6 +5,6 @@
 EXTRA_AFLAGS := -ansi
 EXTRA_CFLAGS := -Werror
 
-obj-y    := ultra.o tlb.o fault.o init.o generic.o extable.o
+obj-y    := ultra.o tlb.o fault.o init.o generic.o
 
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
diff --git a/arch/sparc64/mm/extable.c b/arch/sparc64/mm/extable.c
deleted file mode 100644
index ec334297ff4f..000000000000
--- a/arch/sparc64/mm/extable.c
+++ /dev/null
@@ -1,80 +0,0 @@
-/*
- * linux/arch/sparc64/mm/extable.c
- */
-
-#include <linux/config.h>
-#include <linux/module.h>
-#include <asm/uaccess.h>
-
-extern const struct exception_table_entry __start___ex_table[];
-extern const struct exception_table_entry __stop___ex_table[];
-
-void sort_extable(struct exception_table_entry *start,
-		  struct exception_table_entry *finish)
-{
-}
-
-/* Caller knows they are in a range if ret->fixup == 0 */
-const struct exception_table_entry *
-search_extable(const struct exception_table_entry *start,
-	       const struct exception_table_entry *last,
-	       unsigned long value)
-{
-	const struct exception_table_entry *walk;
-
-	/* Single insn entries are encoded as:
-	 *	word 1:	insn address
-	 *	word 2:	fixup code address
-	 *
-	 * Range entries are encoded as:
-	 *	word 1: first insn address
-	 *	word 2: 0
-	 *	word 3: last insn address + 4 bytes
-	 *	word 4: fixup code address
-	 *
-	 * See asm/uaccess.h for more details.
-	 */
-
-	/* 1. Try to find an exact match. */
-	for (walk = start; walk <= last; walk++) {
-		if (walk->fixup == 0) {
-			/* A range entry, skip both parts. */
-			walk++;
-			continue;
-		}
-
-		if (walk->insn == value)
-			return walk;
-	}
-
-	/* 2. Try to find a range match. */
-	for (walk = start; walk <= (last - 1); walk++) {
-		if (walk->fixup)
-			continue;
-
-		if (walk[0].insn <= value && walk[1].insn > value)
-			return walk;
-
-		walk++;
-	}
-
-        return NULL;
-}
-
-/* Special extable search, which handles ranges.  Returns fixup */
-unsigned long search_extables_range(unsigned long addr, unsigned long *g2)
-{
-	const struct exception_table_entry *entry;
-
-	entry = search_exception_tables(addr);
-	if (!entry)
-		return 0;
-
-	/* Inside range?  Fix g2 and return correct fixup */
-	if (!entry->fixup) {
-		*g2 = (addr - entry->insn) / 4;
-		return (entry + 1)->fixup;
-	}
-
-	return entry->fixup;
-}
diff --git a/arch/sparc64/mm/fault.c b/arch/sparc64/mm/fault.c
index db1e3310e907..59dc9a2ece5a 100644
--- a/arch/sparc64/mm/fault.c
+++ b/arch/sparc64/mm/fault.c
@@ -242,7 +242,6 @@ static unsigned int get_fault_insn(struct pt_regs *regs, unsigned int insn)
 static void do_kernel_fault(struct pt_regs *regs, int si_code, int fault_code,
 			    unsigned int insn, unsigned long address)
 {
-	unsigned long g2;
 	unsigned char asi = ASI_P;
  
 	if ((!insn) && (regs->tstate & TSTATE_PRIV))
@@ -273,11 +272,9 @@ static void do_kernel_fault(struct pt_regs *regs, int si_code, int fault_code,
 		}
 	}
 		
-	g2 = regs->u_regs[UREG_G2];
-
 	/* Is this in ex_table? */
 	if (regs->tstate & TSTATE_PRIV) {
-		unsigned long fixup;
+		const struct exception_table_entry *entry;
 
 		if (asi == ASI_P && (insn & 0xc0800000) == 0xc0800000) {
 			if (insn & 0x2000)
@@ -288,10 +285,9 @@ static void do_kernel_fault(struct pt_regs *regs, int si_code, int fault_code,
 	
 		/* Look in asi.h: All _S asis have LS bit set */
 		if ((asi & 0x1) &&
-		    (fixup = search_extables_range(regs->tpc, &g2))) {
-			regs->tpc = fixup;
+		    (entry = search_exception_tables(regs->tpc))) {
+			regs->tpc = entry->fixup;
 			regs->tnpc = regs->tpc + 4;
-			regs->u_regs[UREG_G2] = g2;
 			return;
 		}
 	} else {