xref: /third_party/ltp/testcases/kernel/mem/hugetlb/hugemmap/hugemmap01.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) International Business Machines  Corp., 2004
 * Copyright (c) Linux Test Project, 2004-2017
 *
 * Test Name: hugemmap01
 *
 * Test Description:
 *  Verify that, mmap() succeeds when used to map a file in a hugetlbfs.
 *
 * Expected Result:
 *  mmap() should succeed returning the address of the hugetlb mapped region.
 *  The number of free huge pages should decrease.
 *
 * Test:
 *  Loop if the proper options are given.
 *  Execute system call
 *  Check return code, if system call failed (return=-1)
 *  Log the errno and Issue a FAIL message.
 *
 * HISTORY
 *  04/2004 Written by Robbie Williamson
 */

#include <stdio.h>
#include <sys/mount.h>
#include <limits.h>
#include <sys/param.h>
#include "hugetlb.h"

static long *addr;
static int  fildes;
static long beforetest;
static long aftertest;
static long hugepagesmapped;
static char TEMPFILE[MAXPATHLEN];

static void test_hugemmap(void)
{
	long page_sz = 0;

	fildes = SAFE_OPEN(TEMPFILE, O_RDWR | O_CREAT, 0666);

	beforetest = SAFE_READ_MEMINFO("HugePages_Free:");

	page_sz = SAFE_READ_MEMINFO("Hugepagesize:") * 1024;

	addr = mmap(NULL, page_sz, PROT_READ | PROT_WRITE,
			MAP_SHARED, fildes, 0);

	if (addr == MAP_FAILED) {
		tst_res(TFAIL | TERRNO, "mmap() Failed on %s",
				TEMPFILE);
	} else {
		tst_res(TPASS, "call succeeded");

		/* force to allocate page and change HugePages_Free */
		*(int *)addr = 0;
		/* Make sure the number of free huge pages AFTER testing decreased */
		aftertest = SAFE_READ_MEMINFO("HugePages_Free:");
		hugepagesmapped = beforetest - aftertest;
		if (hugepagesmapped < 1)
			tst_res(TWARN, "Number of HUGEPAGES_FREE stayed the"
					" same. Okay if multiple copies running due"
					" to test collision.");
		munmap(addr, page_sz);
	}

	close(fildes);
}

void setup(void)
{
	if (tst_hugepages == 0)
		tst_brk(TCONF, "Not enough hugepages for testing.");

	if (!Hopt)
		Hopt = tst_get_tmpdir();
	SAFE_MOUNT("none", Hopt, "hugetlbfs", 0, NULL);

	snprintf(TEMPFILE, sizeof(TEMPFILE), "%s/mmapfile%d", Hopt, getpid());
}

void cleanup(void)
{
	unlink(TEMPFILE);
	umount(Hopt);
}

static struct tst_test test = {
	.needs_root = 1,
	.needs_tmpdir = 1,
	.options = (struct tst_option[]) {
		{"H:", &Hopt,   "Location of hugetlbfs, i.e.  -H /var/hugetlbfs"},
		{"s:", &nr_opt, "Set the number of the been allocated hugepages"},
		{}
	},
	.setup = setup,
	.cleanup = cleanup,
	.test_all = test_hugemmap,
	.hugepages = {128, TST_REQUEST},
};