Add test generic/319 for deferred cmtime update after mmapped write

.gitignore

@@ -62,6 +62,7 @@
 /src/makeextents
 /src/metaperf
 /src/mmapcat
+/src/mmap_cmtime
 /src/multi_open_unlink
 /src/nametest
 /src/nsexec

src/Makefile

@@ -18,7 +18,8 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
 	locktest unwritten_mmap bulkstat_unlink_test t_stripealign \
 	bulkstat_unlink_test_modified t_dir_offset t_futimens t_immutable \
 	stale_handle pwrite_mmap_blocked t_dir_offset2 seek_sanity_test \
-	seek_copy_test t_readdir_1 t_readdir_2 fsync-tester nsexec
+	seek_copy_test t_readdir_1 t_readdir_2 fsync-tester nsexec \
+	mmap_cmtime
 
 SUBDIRS =
 

src/mmap_cmtime.c

@@ -0,0 +1,270 @@
+/*
+ * Test ctime and mtime are updated on truncate(2) and ftruncate(2)
+ *
+ * Copyright (c) 2013 Andrew Lutomirski
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <string.h>
+#include <poll.h>
+#include <err.h>
+#include <stdbool.h>
+#include <time.h>
+
+static int pagesize, map_len;
+static int fd;
+static bool ns_timestamps = true;
+static int errors = 0;
+
+static void wait_ts(void)
+{
+	/*
+	 * Wait for the time to change.  (We need to wait long enough
+	 for the FS * and for the kernel's fs timestamp granularity.)
+	*/
+	usleep(ns_timestamps ? 11000 : 1100000);
+}
+
+static struct timespec get_cmtime(int fd)
+{
+	struct stat stat;
+	if (fstat(fd, &stat) < 0)
+		err(1, "fstat");
+
+	if (stat.st_mtim.tv_sec != stat.st_ctim.tv_sec ||
+	    stat.st_mtim.tv_nsec != stat.st_ctim.tv_nsec) {
+		printf("mtime != ctime\n");
+		errors++;
+	}
+
+	printf("  [DEBUG] get_cmtime: %lld.%09ld\n",
+	       (long long)stat.st_mtim.tv_sec, (long)stat.st_mtim.tv_nsec);
+	wait_ts();
+	return stat.st_mtim;
+}
+
+static struct timespec now()
+{
+	struct timespec ret;
+	clock_gettime(CLOCK_REALTIME, &ret);
+	printf("  [DEBUG] now:        %lld.%09ld\n",
+	       (long long)ret.tv_sec, (long)ret.tv_nsec);
+	wait_ts();
+	return ret;
+}
+
+static bool ts_eq(const struct timespec *a, const struct timespec *b)
+{
+	return a->tv_sec == b->tv_sec && a->tv_nsec == b->tv_nsec;
+}
+
+static bool ts_before(const struct timespec *a, const struct timespec *b)
+{
+	return a->tv_sec < b->tv_sec ||
+		(a->tv_sec == b->tv_sec && a->tv_nsec < b->tv_nsec);
+}
+
+#define CHECK(cond)							\
+	do {								\
+		if (!(cond)) {						\
+			printf("*** failed check: %s\n", #cond);	\
+			errors++;					\
+		}							\
+	} while(0)
+
+static void *map()
+{
+	void *addr = mmap(0, map_len, PROT_READ | PROT_WRITE,
+			  MAP_SHARED, fd, 0);
+	if (addr == MAP_FAILED)
+		err(1, "mmap");
+	return addr;
+}
+
+static void write_page(void *addr, int page)
+{
+	printf("Write page %d\n", page);
+	*((char*)addr + page*pagesize) = 1;
+}
+
+static void unmap(void *addr)
+{
+	printf("munmap\n");
+	munmap(addr, map_len);
+}
+
+static void test_basic()
+{
+	struct timespec t1, t2, t3;
+	void *addr = map();
+
+	printf("\ntest_basic\n");
+
+	t1 = get_cmtime(fd);
+	write_page(addr, 0);
+	t2 = get_cmtime(fd);
+	unmap(addr);
+	t3 = get_cmtime(fd);
+
+	CHECK(ts_before(&t1, &t3));
+	CHECK(ts_eq(&t2, &t1) || ts_eq(&t2, &t3));
+}
+
+static void test_write_twice()
+{
+	struct timespec t1, t2, t3, t4, t5;
+	void *addr = map();
+
+	printf("\ntest_write_twice\n");
+
+	t1 = get_cmtime(fd);
+	write_page(addr, 0);
+	t2 = get_cmtime(fd);
+	t3 = now();
+	write_page(addr, 0);
+	t4 = get_cmtime(fd);
+	unmap(addr);
+	t5 = get_cmtime(fd);
+
+	/* Time must change at most twice. */
+	CHECK(!ts_eq(&t1, &t2) + !ts_eq(&t2, &t4) + !ts_eq(&t4, &t5) <= 2);
+
+	/* The second write must cause an update. */
+	CHECK(ts_before(&t3, &t5));
+}
+
+static void test_write_twice_sync(int sync_style)
+{
+	struct timespec t1, t2, t3, t4, t5, t6;
+	void *addr = map();
+
+	printf("\ntest_write_twice_sync(%d)\n", sync_style);
+
+	t1 = get_cmtime(fd);
+	write_page(addr, 0);
+	t2 = get_cmtime(fd);
+	t3 = now();
+	write_page(addr, 0);
+	t4 = get_cmtime(fd);
+	if (sync_style == 0) {
+		printf("fsync\n");
+		fsync(fd);
+	} else if (sync_style == 1) {
+		printf("MS_SYNC one byte\n");
+		msync(addr, 1, MS_SYNC);
+	} else if (sync_style == 2) {
+		printf("MS_SYNC entire mapping byte\n");
+		msync(addr, map_len, MS_SYNC);
+	} else if (sync_style == 3) {
+		printf("MS_ASYNC one byte\n");
+		msync(addr, 1, MS_ASYNC);
+	} else if (sync_style == 4) {
+		printf("MS_ASYNC entire mapping byte\n");
+		msync(addr, map_len, MS_ASYNC);
+	} else if (sync_style == 5) {
+		printf("fdatasync\n");
+		fdatasync(fd);
+	} else if (sync_style == 6) {
+		printf("sync_file_range one byte\n");
+		sync_file_range(fd, 0, 1,
+				SYNC_FILE_RANGE_WRITE | SYNC_FILE_RANGE_WAIT_AFTER);
+	} else {
+		abort();
+	}
+	t5 = get_cmtime(fd);
+	unmap(addr);
+	t6 = get_cmtime(fd);
+
+	/* Time must change at most twice. */
+	CHECK(!ts_eq(&t1, &t2) + !ts_eq(&t2, &t4) + !ts_eq(&t4, &t5) +
+	      !ts_eq(&t5, &t6) <= 2);
+
+	/* The second write must cause an update. */
+	CHECK(ts_before(&t3, &t5));
+
+	/* Unmap must not cause an update. */
+	CHECK(ts_eq(&t5, &t6));
+}
+
+static void test_two_pages()
+{
+	struct timespec t1, t2, t3, t4;
+	void *addr = map();
+
+	printf("\ntest_two_pages\n");
+
+	t1 = get_cmtime(fd);
+	write_page(addr, 0);
+	write_page(addr, 1);
+	sync_file_range(fd, 0, 1,
+			SYNC_FILE_RANGE_WRITE | SYNC_FILE_RANGE_WAIT_AFTER);
+	t2 = get_cmtime(fd);
+	CHECK(ts_before(&t1, &t2));
+
+	t3 = now();
+	write_page(addr, 1);
+	unmap(addr);
+	t4 = get_cmtime(fd);
+	CHECK(ts_before(&t3, &t4));
+}
+
+int main(int argc, char **argv)
+{
+	if (argc != 2) {
+		printf("Usage: %s filename\n", argv[0]);
+		return 1;
+	}
+
+	pagesize = getpagesize();
+
+	fd = open(argv[1], O_RDWR | O_CREAT | O_EXCL, 0666);
+	if (fd == -1)
+		err(1, "open");
+
+	unlink(argv[1]);
+
+	map_len = 2*pagesize;
+	if (ftruncate(fd, map_len) != 0)
+		err(1, "ftruncate");
+
+	ns_timestamps = (get_cmtime(fd).tv_nsec != 0);
+
+	test_basic();
+	test_write_twice();
+	test_write_twice_sync(0);
+	test_write_twice_sync(1);
+	test_write_twice_sync(2);
+	test_write_twice_sync(3);
+	test_write_twice_sync(4);
+	test_write_twice_sync(5);
+	test_write_twice_sync(6);
+	test_two_pages();
+
+	if (errors) {
+		printf("%d errors\n", errors);
+		return 1;
+	} else {
+		printf("\nPassed!\n");
+		return 0;
+	}
+}

tests/generic/319

@@ -0,0 +1,49 @@
+#! /bin/bash
+# FS QA Test No. 001
+#
+# Test cmtime update after writes to shared writable mmaps
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2013 Andrew Lutomirski.  All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#-----------------------------------------------------------------------
+#
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+    rm -f "$TEST_DIR/file"
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# Modify as appropriate.
+_supported_fs generic
+_supported_os Linux
+
+"$here/src/mmap_cmtime" "$TEST_DIR/file" 2>&1 | tee "$seqres.full" |grep -v '^  \[DEBUG\]'
+status=${PIPESTATUS[0]}
+
+exit $status

tests/generic/319.out

@@ -0,0 +1,60 @@
+QA output created by 319
+
+test_basic
+Write page 0
+munmap
+
+test_write_twice
+Write page 0
+Write page 0
+munmap
+
+test_write_twice_sync(0)
+Write page 0
+Write page 0
+fsync
+munmap
+
+test_write_twice_sync(1)
+Write page 0
+Write page 0
+MS_SYNC one byte
+munmap
+
+test_write_twice_sync(2)
+Write page 0
+Write page 0
+MS_SYNC entire mapping byte
+munmap
+
+test_write_twice_sync(3)
+Write page 0
+Write page 0
+MS_ASYNC one byte
+munmap
+
+test_write_twice_sync(4)
+Write page 0
+Write page 0
+MS_ASYNC entire mapping byte
+munmap
+
+test_write_twice_sync(5)
+Write page 0
+Write page 0
+fdatasync
+munmap
+
+test_write_twice_sync(6)
+Write page 0
+Write page 0
+sync_file_range one byte
+munmap
+
+test_two_pages
+Write page 0
+Write page 1
+Write page 1
+munmap
+
+Passed!