1#include <stdlib.h>
  2#include <string.h>
  3#include <stdio.h>
  4#include <signal.h>
  5#include <unistd.h>
  6#include <sys/mman.h>
  7
  8#include "utils.h"
  9
 10extern char __start___ex_table[];
 11extern char __stop___ex_table[];
 12
 13#if defined(__powerpc64__)
 14#define UCONTEXT_NIA(UC)	(UC)->uc_mcontext.gp_regs[PT_NIP]
 15#elif defined(__powerpc__)
 16#define UCONTEXT_NIA(UC)	(UC)->uc_mcontext.uc_regs->gregs[PT_NIP]
 17#else
 18#error implement UCONTEXT_NIA
 19#endif
 20
 21static void segv_handler(int signr, siginfo_t *info, void *ptr)
 22{
 23	ucontext_t *uc = (ucontext_t *)ptr;
 24	unsigned long addr = (unsigned long)info->si_addr;
 25	unsigned long *ip = &UCONTEXT_NIA(uc);
 26	unsigned long *ex_p = (unsigned long *)__start___ex_table;
 27
 28	while (ex_p < (unsigned long *)__stop___ex_table) {
 29		unsigned long insn, fixup;
 30
 31		insn = *ex_p++;
 32		fixup = *ex_p++;
 33
 34		if (insn == *ip) {
 35			*ip = fixup;
 36			return;
 37		}
 38	}
 39
 40	printf("No exception table match for NIA %lx ADDR %lx\n", *ip, addr);
 41	abort();
 42}
 43
 44static void setup_segv_handler(void)
 45{
 46	struct sigaction action;
 47
 48	memset(&action, 0, sizeof(action));
 49	action.sa_sigaction = segv_handler;
 50	action.sa_flags = SA_SIGINFO;
 51	sigaction(SIGSEGV, &action, NULL);
 52}
 53
 54unsigned long COPY_LOOP(void *to, const void *from, unsigned long size);
 55unsigned long test_copy_tofrom_user_reference(void *to, const void *from, unsigned long size);
 56
 57static int total_passed;
 58static int total_failed;
 59
 60static void do_one_test(char *dstp, char *srcp, unsigned long len)
 61{
 62	unsigned long got, expected;
 63
 64	got = COPY_LOOP(dstp, srcp, len);
 65	expected = test_copy_tofrom_user_reference(dstp, srcp, len);
 66
 67	if (got != expected) {
 68		total_failed++;
 69		printf("FAIL from=%p to=%p len=%ld returned %ld, expected %ld\n",
 70		       srcp, dstp, len, got, expected);
 71		//abort();
 72	} else
 73		total_passed++;
 74}
 75
 76//#define MAX_LEN 512
 77#define MAX_LEN 16
 78
 79int test_copy_exception(void)
 80{
 81	int page_size;
 82	static char *p, *q;
 83	unsigned long src, dst, len;
 84
 85	page_size = getpagesize();
 86	p = mmap(NULL, page_size * 2, PROT_READ|PROT_WRITE,
 87		MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
 88
 89	if (p == MAP_FAILED) {
 90		perror("mmap");
 91		exit(1);
 92	}
 93
 94	memset(p, 0, page_size);
 95
 96	setup_segv_handler();
 97
 98	if (mprotect(p + page_size, page_size, PROT_NONE)) {
 99		perror("mprotect");
100		exit(1);
101	}
102
103	q = p + page_size - MAX_LEN;
104
105	for (src = 0; src < MAX_LEN; src++) {
106		for (dst = 0; dst < MAX_LEN; dst++) {
107			for (len = 0; len < MAX_LEN+1; len++) {
108				// printf("from=%p to=%p len=%ld\n", q+dst, q+src, len);
109				do_one_test(q+dst, q+src, len);
110			}
111		}
112	}
113
114	printf("Totals:\n");
115	printf("  Pass: %d\n", total_passed);
116	printf("  Fail: %d\n", total_failed);
117
118	return 0;
119}
120
121int main(void)
122{
123	return test_harness(test_copy_exception, str(COPY_LOOP));
124}