int main(int argc, char *argv[])
{
volatile int a __attribute__((__unused__));
char *buffer = "HELLO WORLD!";
char *data;
int fd, err, ret = 0;
if (argc < 2) {
printf("Usage: %s <pmem file>\n", basename(argv[0]));
exit(0);
}
fd = open(argv[1], O_RDWR|O_CREAT, S_IRUSR|S_IWUSR);
if (fd < 0)
err_exit("fd");
/*
* This allows us to map a huge zero page, and we do it at a non-zero
* offset for a little additional testing.
*/
ftruncate(fd, 0);
ftruncate(fd, MiB(4));
data = mmap(NULL, MiB(2), PROT_READ, MAP_SHARED, fd, MiB(2));
/*
* This faults in a 2MiB zero page to satisfy the read.
* 'a' is volatile so this read doesn't get optimized out.
*/
a = data[0];
pwrite(fd, buffer, strlen(buffer), MiB(2));
/*
* Try and use the mmap to read back the data we just wrote with
* pwrite(). If the kernel bug is present the mapping from the 2MiB
* zero page will still be intact, and we'll read back zeros instead.
*/
if (strncmp(buffer, data, strlen(buffer))) {
fprintf(stderr, "strncmp mismatch: '%s' vs '%s'\n", buffer,
data);
ret = 1;
}
err = munmap(data, MiB(2));
if (err < 0)
err_exit("munmap");
err = close(fd);
if (err < 0)
err_exit("close");
return ret;
}
#define MAX_LOGIC_BLK_PER_ZONE 1000
#define MAX_PHYS_BLK_PER_ZONE 1024
#define KiB(x) ( (x) * 1024L )
#define MiB(x) ( KiB(x) * 1024L )
typedef struct {
unsigned long size;
unsigned short cyl;
unsigned char head;
unsigned char sec;
} chs_entry_t;
static const chs_entry_t chs_table[] = {
{ MiB( 1), 125, 4, 4 },
{ MiB( 2), 125, 4, 8 },
{ MiB( 4), 250, 4, 8 },
{ MiB( 8), 250, 4, 16 },
{ MiB( 16), 500, 4, 16 },
{ MiB( 32), 500, 8, 16 },
{ MiB( 64), 500, 8, 32 },
{ MiB(128), 500, 16, 32 },
{ 0 },
};
static int get_chs(unsigned long size, unsigned short *cyl, unsigned char *head,
unsigned char *sec)
{
int k;
int found = 0;
inline U32 GiB(U32 x) {
return MiB(x) * 1024;
}