1/*
2 * linux/arch/sparc/mm/extable.c
3 */
4
5#include <linux/module.h>
6#include <asm/uaccess.h>
7
8void sort_extable(struct exception_table_entry *start,
9		  struct exception_table_entry *finish)
10{
11}
12
13/* Caller knows they are in a range if ret->fixup == 0 */
14const struct exception_table_entry *
15search_extable(const struct exception_table_entry *start,
16	       const struct exception_table_entry *last,
17	       unsigned long value)
18{
19	const struct exception_table_entry *walk;
20
21	/* Single insn entries are encoded as:
22	 *	word 1:	insn address
23	 *	word 2:	fixup code address
24	 *
25	 * Range entries are encoded as:
26	 *	word 1: first insn address
27	 *	word 2: 0
28	 *	word 3: last insn address + 4 bytes
29	 *	word 4: fixup code address
30	 *
31	 * See asm/uaccess.h for more details.
32	 */
33
34	/* 1. Try to find an exact match. */
35	for (walk = start; walk <= last; walk++) {
36		if (walk->fixup == 0) {
37			/* A range entry, skip both parts. */
38			walk++;
39			continue;
40		}
41
42		if (walk->insn == value)
43			return walk;
44	}
45
46	/* 2. Try to find a range match. */
47	for (walk = start; walk <= (last - 1); walk++) {
48		if (walk->fixup)
49			continue;
50
51		if (walk[0].insn <= value && walk[1].insn > value)
52			return walk;
53
54		walk++;
55	}
56
57        return NULL;
58}
59
60/* Special extable search, which handles ranges.  Returns fixup */
61unsigned long search_extables_range(unsigned long addr, unsigned long *g2)
62{
63	const struct exception_table_entry *entry;
64
65	entry = search_exception_tables(addr);
66	if (!entry)
67		return 0;
68
69	/* Inside range?  Fix g2 and return correct fixup */
70	if (!entry->fixup) {
71		*g2 = (addr - entry->insn) / 4;
72		return (entry + 1)->fixup;
73	}
74
75	return entry->fixup;
76}
77