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1// SPDX-License-Identifier: GPL-2.02#define _GNU_SOURCE3#include <sys/mman.h>4#include <stdint.h>5#include <unistd.h>6#include <string.h>7#include <sys/time.h>8#include <sys/resource.h>9#include <stdbool.h>10#include "../kselftest.h"11#include "mlock2.h"12 13struct vm_boundaries {14	unsigned long start;15	unsigned long end;16};17 18static int get_vm_area(unsigned long addr, struct vm_boundaries *area)19{20	FILE *file;21	int ret = 1;22	char line[1024] = {0};23	unsigned long start;24	unsigned long end;25 26	if (!area)27		return ret;28 29	file = fopen("/proc/self/maps", "r");30	if (!file) {31		perror("fopen");32		return ret;33	}34 35	memset(area, 0, sizeof(struct vm_boundaries));36 37	while(fgets(line, 1024, file)) {38		if (sscanf(line, "%lx-%lx", &start, &end) != 2) {39			ksft_print_msg("cannot parse /proc/self/maps\n");40			goto out;41		}42 43		if (start <= addr && end > addr) {44			area->start = start;45			area->end = end;46			ret = 0;47			goto out;48		}49	}50out:51	fclose(file);52	return ret;53}54 55#define VMFLAGS "VmFlags:"56 57static bool is_vmflag_set(unsigned long addr, const char *vmflag)58{59	char *line = NULL;60	char *flags;61	size_t size = 0;62	bool ret = false;63	FILE *smaps;64 65	smaps = seek_to_smaps_entry(addr);66	if (!smaps) {67		ksft_print_msg("Unable to parse /proc/self/smaps\n");68		goto out;69	}70 71	while (getline(&line, &size, smaps) > 0) {72		if (!strstr(line, VMFLAGS)) {73			free(line);74			line = NULL;75			size = 0;76			continue;77		}78 79		flags = line + strlen(VMFLAGS);80		ret = (strstr(flags, vmflag) != NULL);81		goto out;82	}83 84out:85	free(line);86	fclose(smaps);87	return ret;88}89 90#define SIZE "Size:"91#define RSS  "Rss:"92#define LOCKED "lo"93 94static unsigned long get_value_for_name(unsigned long addr, const char *name)95{96	char *line = NULL;97	size_t size = 0;98	char *value_ptr;99	FILE *smaps = NULL;100	unsigned long value = -1UL;101 102	smaps = seek_to_smaps_entry(addr);103	if (!smaps) {104		ksft_print_msg("Unable to parse /proc/self/smaps\n");105		goto out;106	}107 108	while (getline(&line, &size, smaps) > 0) {109		if (!strstr(line, name)) {110			free(line);111			line = NULL;112			size = 0;113			continue;114		}115 116		value_ptr = line + strlen(name);117		if (sscanf(value_ptr, "%lu kB", &value) < 1) {118			ksft_print_msg("Unable to parse smaps entry for Size\n");119			goto out;120		}121		break;122	}123 124out:125	if (smaps)126		fclose(smaps);127	free(line);128	return value;129}130 131static bool is_vma_lock_on_fault(unsigned long addr)132{133	bool locked;134	unsigned long vma_size, vma_rss;135 136	locked = is_vmflag_set(addr, LOCKED);137	if (!locked)138		return false;139 140	vma_size = get_value_for_name(addr, SIZE);141	vma_rss = get_value_for_name(addr, RSS);142 143	/* only one page is faulted in */144	return (vma_rss < vma_size);145}146 147#define PRESENT_BIT     0x8000000000000000ULL148#define PFN_MASK        0x007FFFFFFFFFFFFFULL149#define UNEVICTABLE_BIT (1UL << 18)150 151static int lock_check(unsigned long addr)152{153	bool locked;154	unsigned long vma_size, vma_rss;155 156	locked = is_vmflag_set(addr, LOCKED);157	if (!locked)158		return false;159 160	vma_size = get_value_for_name(addr, SIZE);161	vma_rss = get_value_for_name(addr, RSS);162 163	return (vma_rss == vma_size);164}165 166static int unlock_lock_check(char *map)167{168	if (is_vmflag_set((unsigned long)map, LOCKED)) {169		ksft_print_msg("VMA flag %s is present on page 1 after unlock\n", LOCKED);170		return 1;171	}172 173	return 0;174}175 176static void test_mlock_lock(void)177{178	char *map;179	unsigned long page_size = getpagesize();180 181	map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,182		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);183	if (map == MAP_FAILED)184		ksft_exit_fail_msg("mmap error: %s", strerror(errno));185 186	if (mlock2_(map, 2 * page_size, 0)) {187		munmap(map, 2 * page_size);188		ksft_exit_fail_msg("mlock2(0): %s\n", strerror(errno));189	}190 191	ksft_test_result(lock_check((unsigned long)map), "%s: Locked\n", __func__);192 193	/* Now unlock and recheck attributes */194	if (munlock(map, 2 * page_size)) {195		munmap(map, 2 * page_size);196		ksft_exit_fail_msg("munlock(): %s\n", strerror(errno));197	}198 199	ksft_test_result(!unlock_lock_check(map), "%s: Locked\n", __func__);200	munmap(map, 2 * page_size);201}202 203static int onfault_check(char *map)204{205	*map = 'a';206	if (!is_vma_lock_on_fault((unsigned long)map)) {207		ksft_print_msg("VMA is not marked for lock on fault\n");208		return 1;209	}210 211	return 0;212}213 214static int unlock_onfault_check(char *map)215{216	unsigned long page_size = getpagesize();217 218	if (is_vma_lock_on_fault((unsigned long)map) ||219	    is_vma_lock_on_fault((unsigned long)map + page_size)) {220		ksft_print_msg("VMA is still lock on fault after unlock\n");221		return 1;222	}223 224	return 0;225}226 227static void test_mlock_onfault(void)228{229	char *map;230	unsigned long page_size = getpagesize();231 232	map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,233		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);234	if (map == MAP_FAILED)235		ksft_exit_fail_msg("mmap error: %s", strerror(errno));236 237	if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {238		munmap(map, 2 * page_size);239		ksft_exit_fail_msg("mlock2(MLOCK_ONFAULT): %s\n", strerror(errno));240	}241 242	ksft_test_result(!onfault_check(map), "%s: VMA marked for lock on fault\n", __func__);243 244	/* Now unlock and recheck attributes */245	if (munlock(map, 2 * page_size)) {246		munmap(map, 2 * page_size);247		ksft_exit_fail_msg("munlock(): %s\n", strerror(errno));248	}249 250	ksft_test_result(!unlock_onfault_check(map), "VMA open lock after fault\n");251	munmap(map, 2 * page_size);252}253 254static void test_lock_onfault_of_present(void)255{256	char *map;257	unsigned long page_size = getpagesize();258 259	map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,260		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);261	if (map == MAP_FAILED)262		ksft_exit_fail_msg("mmap error: %s", strerror(errno));263 264	*map = 'a';265 266	if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {267		munmap(map, 2 * page_size);268		ksft_test_result_fail("mlock2(MLOCK_ONFAULT) error: %s", strerror(errno));269	}270 271	ksft_test_result(is_vma_lock_on_fault((unsigned long)map) ||272			 is_vma_lock_on_fault((unsigned long)map + page_size),273			 "VMA with present pages is not marked lock on fault\n");274	munmap(map, 2 * page_size);275}276 277static void test_munlockall0(void)278{279	char *map;280	unsigned long page_size = getpagesize();281 282	map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,283		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);284	if (map == MAP_FAILED)285		ksft_exit_fail_msg("mmap error: %s\n", strerror(errno));286 287	if (mlockall(MCL_CURRENT)) {288		munmap(map, 2 * page_size);289		ksft_exit_fail_msg("mlockall(MCL_CURRENT): %s\n", strerror(errno));290	}291 292	ksft_test_result(lock_check((unsigned long)map), "%s: Locked memory area\n", __func__);293 294	if (munlockall()) {295		munmap(map, 2 * page_size);296		ksft_exit_fail_msg("munlockall(): %s\n", strerror(errno));297	}298 299	ksft_test_result(!unlock_lock_check(map), "%s: No locked memory\n", __func__);300	munmap(map, 2 * page_size);301}302 303static void test_munlockall1(void)304{305	char *map;306	unsigned long page_size = getpagesize();307 308	map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,309		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);310	if (map == MAP_FAILED)311		ksft_exit_fail_msg("mmap error: %s", strerror(errno));312 313	if (mlockall(MCL_CURRENT | MCL_ONFAULT)) {314		munmap(map, 2 * page_size);315		ksft_exit_fail_msg("mlockall(MCL_CURRENT | MCL_ONFAULT): %s\n", strerror(errno));316	}317 318	ksft_test_result(!onfault_check(map), "%s: VMA marked for lock on fault\n", __func__);319 320	if (munlockall()) {321		munmap(map, 2 * page_size);322		ksft_exit_fail_msg("munlockall(): %s\n", strerror(errno));323	}324 325	ksft_test_result(!unlock_onfault_check(map), "%s: Unlocked\n", __func__);326 327	if (mlockall(MCL_CURRENT | MCL_FUTURE)) {328		munmap(map, 2 * page_size);329		ksft_exit_fail_msg("mlockall(MCL_CURRENT | MCL_FUTURE): %s\n", strerror(errno));330	}331 332	ksft_test_result(lock_check((unsigned long)map), "%s: Locked\n", __func__);333 334	if (munlockall()) {335		munmap(map, 2 * page_size);336		ksft_exit_fail_msg("munlockall() %s\n", strerror(errno));337	}338 339	ksft_test_result(!unlock_lock_check(map), "%s: No locked memory\n", __func__);340	munmap(map, 2 * page_size);341}342 343static void test_vma_management(bool call_mlock)344{345	void *map;346	unsigned long page_size = getpagesize();347	struct vm_boundaries page1;348	struct vm_boundaries page2;349	struct vm_boundaries page3;350 351	map = mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE,352		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);353	if (map == MAP_FAILED)354		ksft_exit_fail_msg("mmap error: %s", strerror(errno));355 356	if (call_mlock && mlock2_(map, 3 * page_size, MLOCK_ONFAULT)) {357		munmap(map, 3 * page_size);358		ksft_test_result_fail("mlock error: %s", strerror(errno));359	}360 361	if (get_vm_area((unsigned long)map, &page1) ||362	    get_vm_area((unsigned long)map + page_size, &page2) ||363	    get_vm_area((unsigned long)map + page_size * 2, &page3)) {364		munmap(map, 3 * page_size);365		ksft_test_result_fail("couldn't find mapping in /proc/self/maps");366	}367 368	/*369	 * Before we unlock a portion, we need to that all three pages are in370	 * the same VMA.  If they are not we abort this test (Note that this is371	 * not a failure)372	 */373	if (page1.start != page2.start || page2.start != page3.start) {374		munmap(map, 3 * page_size);375		ksft_test_result_fail("VMAs are not merged to start, aborting test");376	}377 378	if (munlock(map + page_size, page_size)) {379		munmap(map, 3 * page_size);380		ksft_test_result_fail("munlock(): %s", strerror(errno));381	}382 383	if (get_vm_area((unsigned long)map, &page1) ||384	    get_vm_area((unsigned long)map + page_size, &page2) ||385	    get_vm_area((unsigned long)map + page_size * 2, &page3)) {386		munmap(map, 3 * page_size);387		ksft_test_result_fail("couldn't find mapping in /proc/self/maps");388	}389 390	/* All three VMAs should be different */391	if (page1.start == page2.start || page2.start == page3.start) {392		munmap(map, 3 * page_size);393		ksft_test_result_fail("failed to split VMA for munlock");394	}395 396	/* Now unlock the first and third page and check the VMAs again */397	if (munlock(map, page_size * 3)) {398		munmap(map, 3 * page_size);399		ksft_test_result_fail("munlock(): %s", strerror(errno));400	}401 402	if (get_vm_area((unsigned long)map, &page1) ||403	    get_vm_area((unsigned long)map + page_size, &page2) ||404	    get_vm_area((unsigned long)map + page_size * 2, &page3)) {405		munmap(map, 3 * page_size);406		ksft_test_result_fail("couldn't find mapping in /proc/self/maps");407	}408 409	/* Now all three VMAs should be the same */410	if (page1.start != page2.start || page2.start != page3.start) {411		munmap(map, 3 * page_size);412		ksft_test_result_fail("failed to merge VMAs after munlock");413	}414 415	ksft_test_result_pass("%s call_mlock %d\n", __func__, call_mlock);416	munmap(map, 3 * page_size);417}418 419static void test_mlockall(void)420{421	if (mlockall(MCL_CURRENT | MCL_ONFAULT | MCL_FUTURE))422		ksft_exit_fail_msg("mlockall failed: %s\n", strerror(errno));423 424	test_vma_management(false);425	munlockall();426}427 428int main(int argc, char **argv)429{430	int ret, size = 3 * getpagesize();431	void *map;432 433	ksft_print_header();434 435	map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);436	if (map == MAP_FAILED)437		ksft_exit_fail_msg("mmap error: %s", strerror(errno));438 439	ret = mlock2_(map, size, MLOCK_ONFAULT);440	if (ret && errno == ENOSYS)441		ksft_finished();442 443	munmap(map, size);444 445	ksft_set_plan(13);446 447	test_mlock_lock();448	test_mlock_onfault();449	test_munlockall0();450	test_munlockall1();451	test_lock_onfault_of_present();452	test_vma_management(true);453	test_mlockall();454 455	ksft_finished();456}457