mbligh | 2b8cd19 | 2008-11-20 17:27:17 +0000 | [diff] [blame] | 1 | #include <stdio.h> |
| 2 | #include <stdlib.h> |
| 3 | #include <sys/mman.h> |
| 4 | #include <unistd.h> |
| 5 | #include <fcntl.h> |
| 6 | |
| 7 | /* This program allocates memory with multiple calls to remap. This |
| 8 | * can be used to verify if the remap api is working correctly. */ |
| 9 | |
| 10 | #define PAGE_SHIFT 12 |
| 11 | |
| 12 | #define ROUND_PAGES(memsize) ((memsize >> (PAGE_SHIFT)) << PAGE_SHIFT) |
| 13 | |
| 14 | int main(int argc, char *argv[]) { |
| 15 | unsigned int memsize; |
| 16 | char *mem; |
| 17 | int i, numpages, fd; |
| 18 | |
| 19 | if (argc != 2) { |
| 20 | printf("Usage: %s <memory_size>\n", argv[0]); |
| 21 | exit(EXIT_FAILURE); |
| 22 | } |
| 23 | |
| 24 | memsize = strtoul(argv[1], NULL, 10); |
| 25 | |
| 26 | memsize = ROUND_PAGES(memsize); |
| 27 | |
| 28 | /* We should be limited to < 4G so any size other than 0 is ok */ |
| 29 | if (memsize == 0) { |
| 30 | printf("Invalid memsize\n"); |
| 31 | exit(EXIT_FAILURE); |
| 32 | } |
| 33 | |
| 34 | numpages = memsize >> PAGE_SHIFT; |
| 35 | |
| 36 | mem = mmap(0, memsize, PROT_READ | PROT_WRITE, |
| 37 | MAP_PRIVATE | MAP_ANONYMOUS, |
| 38 | -1, 0); |
| 39 | |
| 40 | if (mem == (void*) -1) { |
| 41 | perror("Failed to allocate anon private memory using mmap\n"); |
| 42 | exit(EXIT_FAILURE); |
| 43 | } |
| 44 | |
| 45 | for (i = 2; i <= 16; i <<= 1) { |
| 46 | mem = mremap(mem , memsize * (i >> 1), |
| 47 | memsize * i, |
| 48 | 1 /* MREMAP_MAYMOVE */); |
| 49 | |
| 50 | if (mem == MAP_FAILED) { |
| 51 | perror("Failed to remap expand anon private memory\n"); |
| 52 | exit(EXIT_FAILURE); |
| 53 | } |
| 54 | |
| 55 | printf("Successfully remapped %d bytes @%p\n", |
| 56 | memsize * i, mem); |
| 57 | } |
| 58 | |
| 59 | if (munmap(mem, memsize * 16)) { |
| 60 | perror("Could not unmap and free memory\n"); |
| 61 | exit(EXIT_FAILURE); |
| 62 | } |
| 63 | |
| 64 | mem = mmap(0, memsize, PROT_READ | PROT_WRITE, |
| 65 | MAP_PRIVATE | MAP_ANONYMOUS, |
| 66 | -1, 0); |
| 67 | |
| 68 | if (mem == (void*) -1) { |
| 69 | perror("Failed to allocate anon private memory using mmap\n"); |
| 70 | exit(EXIT_FAILURE); |
| 71 | } |
| 72 | |
| 73 | exit(EXIT_SUCCESS); |
| 74 | } |