1 // SPDX-License-Identifier: GPL-2.0 <<
2 /* 1 /*
3 * linux/arch/arm/mm/extable.c !! 2 * arch/ppc/mm/extable.c
>> 3 *
>> 4 * from arch/i386/mm/extable.c
4 */ 5 */
5 #include <linux/extable.h> <<
6 #include <linux/uaccess.h> <<
7 6
8 int fixup_exception(struct pt_regs *regs) !! 7 #include <linux/config.h>
>> 8 #include <linux/module.h>
>> 9 #include <linux/init.h>
>> 10 #include <asm/uaccess.h>
>> 11
>> 12 extern struct exception_table_entry __start___ex_table[];
>> 13 extern struct exception_table_entry __stop___ex_table[];
>> 14
>> 15 /*
>> 16 * The exception table needs to be sorted because we use the macros
>> 17 * which put things into the exception table in a variety of segments
>> 18 * such as the prep, pmac, chrp, etc. segments as well as the init
>> 19 * segment and the main kernel text segment.
>> 20 */
>> 21 static inline void
>> 22 sort_ex_table(struct exception_table_entry *start,
>> 23 struct exception_table_entry *finish)
9 { 24 {
10 const struct exception_table_entry *fi !! 25 struct exception_table_entry el, *p, *q;
11 26
12 fixup = search_exception_tables(instru !! 27 /* insertion sort */
13 if (fixup) { !! 28 for (p = start + 1; p < finish; ++p) {
14 regs->ARM_pc = fixup->fixup; !! 29 /* start .. p-1 is sorted */
15 #ifdef CONFIG_THUMB2_KERNEL !! 30 if (p[0].insn < p[-1].insn) {
16 /* Clear the IT state to avoid !! 31 /* move element p down to its right place */
17 regs->ARM_cpsr &= ~PSR_IT_MASK !! 32 el = *p;
18 #endif !! 33 q = p;
>> 34 do {
>> 35 /* el comes before q[-1], move q[-1] up one */
>> 36 q[0] = q[-1];
>> 37 --q;
>> 38 } while (q > start && el.insn < q[-1].insn);
>> 39 *q = el;
>> 40 }
19 } 41 }
>> 42 }
>> 43
>> 44 void __init
>> 45 sort_exception_table(void)
>> 46 {
>> 47 sort_ex_table(__start___ex_table, __stop___ex_table);
>> 48 }
>> 49
>> 50 /* Simple binary search */
>> 51 const struct exception_table_entry *
>> 52 search_extable(const struct exception_table_entry *first,
>> 53 const struct exception_table_entry *last,
>> 54 unsigned long value)
>> 55 {
>> 56 while (first <= last) {
>> 57 const struct exception_table_entry *mid;
>> 58 long diff;
20 59
21 return fixup != NULL; !! 60 mid = (last - first) / 2 + first;
>> 61 diff = mid->insn - value;
>> 62 if (diff == 0)
>> 63 return mid;
>> 64 else if (diff < 0)
>> 65 first = mid+1;
>> 66 else
>> 67 last = mid-1;
>> 68 }
>> 69 return NULL;
22 } 70 }
23 71
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.