xref: /xnu-8792.81.2/tests/vm/anon_max_size.c (revision 19c3b8c28c31cb8130e034cfb5df6bf9ba342d90)
1 #include <darwintest.h>
2 
3 #include <errno.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <string.h>
7 
8 #include <sys/mman.h>
9 
10 #include <mach/mach_error.h>
11 #include <mach/mach_init.h>
12 #include <mach/mach_vm.h>
13 
14 #define ANON_MAX_PAGES 0xFFFFFFFFULL
15 #define ANON_MAX_SIZE (ANON_MAX_PAGES * vm_kernel_page_size)
16 
17 T_DECL(anon_max_size, "Test an ALLOC_MAX_SIZE allocation",
18     T_META_NAMESPACE("xnu.vm"),
19     T_META_RADAR_COMPONENT_NAME("xnu"),
20     T_META_RADAR_COMPONENT_VERSION("VM"),
21     T_META_REQUIRES_SYSCTL_EQ("kern.development", 1))
22 {
23 	kern_return_t kr;
24 	mach_vm_address_t vm_addr;
25 	mach_vm_size_t vm_size;
26 	unsigned char *cp;
27 	int ret;
28 	unsigned char vec;
29 
30 	/* allocate the largest anonymous size possible */
31 	vm_size = ANON_MAX_SIZE;
32 	/* truncate to avoid going over actual max size when rounding up */
33 	vm_size &= ~PAGE_MASK;
34 	vm_addr = 0;
35 	kr = mach_vm_allocate(mach_task_self(),
36 	    &vm_addr,
37 	    vm_size,
38 	    VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE);
39 	if (kr == KERN_NO_SPACE) {
40 		T_SKIP("not enough address space...");
41 	}
42 	T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "vm_allocate(0x%llx)", ANON_MAX_SIZE);
43 
44 	/* dirty the first and last pages */
45 	cp = (unsigned char *)(uintptr_t)vm_addr;
46 	cp[0] = 'a';
47 	cp[vm_size - 1] = 'z';
48 
49 	/* trigger the VM compressor for that VM object */
50 	ret = madvise(cp, (size_t)vm_size, MADV_PAGEOUT);
51 	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "madvise(MADV_PAGEOUT)");
52 
53 	/* wait for the pages to be (asynchronously) compressed */
54 	T_QUIET; T_LOG("waiting for first page to be paged out...");
55 	do {
56 		ret = mincore(&cp[0], 1, (char *)&vec);
57 		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "mincore(1st)");
58 	} while (vec & MINCORE_INCORE);
59 	T_QUIET; T_LOG("waiting for last page to be paged out...");
60 	do {
61 		ret = mincore(&cp[vm_size - 1], 1, (char *)&vec);
62 		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "mincore(last)");
63 	} while (vec & MINCORE_INCORE);
64 
65 	/* trigger pageins and check the contents */
66 	T_QUIET; T_ASSERT_EQ(cp[0], 'a', "first page intact");
67 	T_QUIET; T_ASSERT_EQ(cp[vm_size - 1], 'z', "last page intact");
68 
69 	/* success */
70 	return;
71 }
72