static void check_blocks(void)
{
unsigned int current_page;
int do_seek = 1;
char *buffer;
buffer = xmalloc(pagesize);
current_page = 0;
while (current_page < PAGES) {
if (!check && version == 0) {
page_ok(current_page++);
continue;
}
if (do_seek && lseek(DEV, current_page * pagesize, SEEK_SET) !=
current_page * pagesize)
bb_error_msg_and_die("seek failed in check_blocks");
if ((do_seek = (pagesize != read(DEV, buffer, pagesize)))) {
current_page++;
if (version == 0)
bit_test_and_clear(signature_page, current_page);
else {
if (badpages == MAX_BADPAGES)
bb_error_msg_and_die("too many bad pages");
p->badpages[badpages] = current_page;
}
badpages++;
continue;
}
page_ok(current_page++);
}
if (ENABLE_FEATURE_CLEAN_UP)
free(buffer);
if (badpages > 0)
printf("%d bad page%s\n", badpages, (badpages==1)?"":"s");
}
static void check_blocks(void)
{
unsigned int current_page;
int do_seek = 1;
char *buffer;
buffer = xmalloc(pagesize);
current_page = 0;
while (current_page < PAGES) {
if (!check) {
page_ok(current_page++);
continue;
}
if (do_seek && lseek(DEV, current_page * pagesize, SEEK_SET) !=
current_page * pagesize)
bb_error_msg_and_die("seek failed in check_blocks");
if ((do_seek = (pagesize != read(DEV, buffer, pagesize)))) {
page_bad(current_page++);
continue;
}
page_ok(current_page++);
}
if (badpages == 1)
printf("one bad page\n");
else if (badpages > 1)
printf("%d bad pages\n", badpages);
}
unsigned long os_get_top_address(void)
{
struct sigaction sa, old;
unsigned long bottom = 0;
/*
*/
unsigned long top = 0xffffd000 >> UM_KERN_PAGE_SHIFT;
unsigned long test, original;
printf("Locating the bottom of the address space ... ");
fflush(stdout);
/*
*/
sa.sa_handler = segfault;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_NODEFER;
if (sigaction(SIGSEGV, &sa, &old)) {
perror("os_get_top_address");
exit(1);
}
/*
*/
for (bottom = 0; bottom < top; bottom++) {
if (page_ok(bottom))
break;
}
/* */
if (bottom == top) {
fprintf(stderr, "Unable to determine bottom of address "
"space.\n");
exit(1);
}
printf("0x%x\n", bottom << UM_KERN_PAGE_SHIFT);
printf("Locating the top of the address space ... ");
fflush(stdout);
original = bottom;
/* */
if (page_ok(top))
goto out;
do {
test = bottom + (top - bottom) / 2;
if (page_ok(test))
bottom = test;
else
top = test;
} while (top - bottom > 1);
out:
/* */
if (sigaction(SIGSEGV, &old, NULL)) {
perror("os_get_top_address");
exit(1);
}
top <<= UM_KERN_PAGE_SHIFT;
printf("0x%x\n", top);
return top;
}
unsigned long os_get_top_address(void)
{
struct sigaction sa, old;
unsigned long bottom = 0;
/*
* A 32-bit UML on a 64-bit host gets confused about the VDSO at
* 0xffffe000. It is mapped, is readable, can be reprotected writeable
* and written. However, exec discovers later that it can't be
* unmapped. So, just set the highest address to be checked to just
* below it. This might waste some address space on 4G/4G 32-bit
* hosts, but shouldn't hurt otherwise.
*/
unsigned long top = 0xffffd000 >> UM_KERN_PAGE_SHIFT;
unsigned long test, original;
printf("Locating the bottom of the address space ... ");
fflush(stdout);
/*
* We're going to be longjmping out of the signal handler, so
* SA_DEFER needs to be set.
*/
sa.sa_handler = segfault;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_NODEFER;
if (sigaction(SIGSEGV, &sa, &old)) {
perror("os_get_top_address");
exit(1);
}
/* Manually scan the address space, bottom-up, until we find
* the first valid page (or run out of them).
*/
for (bottom = 0; bottom < top; bottom++) {
if (page_ok(bottom))
break;
}
/* If we've got this far, we ran out of pages. */
if (bottom == top) {
fprintf(stderr, "Unable to determine bottom of address "
"space.\n");
exit(1);
}
printf("0x%x\n", bottom << UM_KERN_PAGE_SHIFT);
printf("Locating the top of the address space ... ");
fflush(stdout);
original = bottom;
/* This could happen with a 4G/4G split */
if (page_ok(top))
goto out;
do {
test = bottom + (top - bottom) / 2;
if (page_ok(test))
bottom = test;
else
top = test;
} while (top - bottom > 1);
out:
/* Restore the old SIGSEGV handling */
if (sigaction(SIGSEGV, &old, NULL)) {
perror("os_get_top_address");
exit(1);
}
top <<= UM_KERN_PAGE_SHIFT;
printf("0x%x\n", top);
return top;
}
