#ifndef PAGE_SIZE
#define PAGE_SIZE sysconf(_SC_PAGE_SIZE)
#endif
+#ifndef MAP_ANONYMOUS
+ #define MAP_ANONYMOUS 0
+#endif
/* max mmap size, *start is the largest power-of-2 size considered */
static size_t mmax(int fd, size_t *start)
void *p;
for (i=n=*start; i>=PAGE_SIZE; i/=2) {
- if ((p=mmap(0, n, PROT_NONE, MAP_PRIVATE, fd, 0)) == MAP_FAILED) {
+ if ((p=mmap(0, n, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, fd, 0)) == MAP_FAILED) {
n -= i/2;
} else {
munmap(p, n);
*/
int t_vmfill(void **p, size_t *n, int len)
{
- int fd = open("/dev/zero", O_RDWR);
+ int fd = MAP_ANONYMOUS ? -1 : open("/dev/zero", O_RDWR);
size_t start = SIZE_MAX/2 + 1;
size_t m;
void *q;
m = mmax(fd, &start);
if (!m)
break;
- q = mmap(0, m, PROT_NONE, MAP_PRIVATE, fd, 0);
+ q = mmap(0, m, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, fd, 0);
if (q == MAP_FAILED)
return -1;
if (i < len) {