1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2022 CTERA Networks. All Rights Reserved.
4 *
5 * Author: Amir Goldstein <amir73il@gmail.com>
6 */
7
8/*\
9 * [Description]
10 * Test special inotify mask flags.
11 *
12 * Regression test for kernel commit:
13 * a32e697cda27 ("inotify: show inotify mask flags in proc fdinfo")
14 */
15
16#include "config.h"
17
18#include <stdio.h>
19#include <unistd.h>
20#include <fcntl.h>
21#include <signal.h>
22#include <sys/wait.h>
23
24#include "tst_test.h"
25#include "tst_safe_macros.h"
26#include "inotify.h"
27
28#if defined(HAVE_SYS_INOTIFY_H)
29#include <sys/inotify.h>
30
31#define EVENT_MAX 32
32/* Size of the event structure, not including the name */
33#define EVENT_SIZE	(sizeof(struct inotify_event))
34#define EVENT_BUF_LEN	(EVENT_MAX * (EVENT_SIZE + 16))
35
36#define	TEST_FILE	"test_file"
37
38static char event_buf[EVENT_BUF_LEN];
39
40static struct tcase {
41	const char *tname;
42	unsigned int mask;
43	int expect_events;
44} tcases[] = {
45	{
46		"Watch for multi events",
47		IN_MODIFY,
48		2,
49	},
50	{
51		"Watch for single event",
52		IN_MODIFY | IN_ONESHOT,
53		1,
54	},
55	{
56		"Watch for events on linked file",
57		IN_MODIFY | IN_EXCL_UNLINK,
58		1,
59	},
60};
61
62static int fd_notify;
63
64static void verify_inotify(unsigned int n)
65{
66	struct tcase *tc = &tcases[n];
67	int fd, len;
68	unsigned int tmpmask;
69	char procfdinfo[100];
70	struct inotify_event *event = (struct inotify_event *)event_buf;
71
72	tst_res(TINFO, "Test #%d: %s", n, tc->tname);
73
74	fd_notify = SAFE_MYINOTIFY_INIT1(O_NONBLOCK);
75
76	SAFE_FILE_PRINTF(TEST_FILE, "1");
77
78	SAFE_MYINOTIFY_ADD_WATCH(fd_notify, ".", tc->mask);
79
80	sprintf(procfdinfo, "/proc/%d/fdinfo/%d", (int)getpid(), fd_notify);
81	if (FILE_LINES_SCANF(procfdinfo, "inotify wd:%*d ino:%*x sdev:%*x mask:%x",
82			     &tmpmask)) {
83		tst_res(TFAIL, "Could not parse inotify fdinfo");
84	} else if (tmpmask != tc->mask) {
85		tst_res(TFAIL, "Incorrect mask %x in inotify fdinfo (expected %x)",
86			tmpmask, tc->mask);
87	} else {
88		tst_res(TPASS, "Correct mask in inotify fdinfo");
89	}
90
91	fd = SAFE_OPEN(TEST_FILE, O_RDWR);
92	SAFE_WRITE(SAFE_WRITE_ALL, fd, "2", 1);
93
94	/*
95	 * Read the 1st IN_MODIFY event
96	 */
97	len = SAFE_READ(0, fd_notify, event_buf, EVENT_BUF_LEN);
98
99	if (len < (int)sizeof(*event)) {
100		tst_res(TFAIL, "Got no events");
101	} else if (event->mask == IN_MODIFY) {
102		tst_res(TPASS, "Got 1st event as expected");
103	} else {
104		tst_res(TFAIL, "Got event 0x%x (expected 0x%x)",
105				event->mask, IN_MODIFY);
106	}
107
108	/*
109	 * Unlink file so IN_EXCL_UNLINK won't get IN_ACCESS event.
110	 * IN_ONESHOT won't get IN_ACCESS event because IN_MODIFY
111	 * was already generated.
112	 */
113	SAFE_UNLINK(TEST_FILE);
114	SAFE_WRITE(SAFE_WRITE_ALL, fd, "3", 1);
115	SAFE_CLOSE(fd);
116
117	/*
118	 * Possibly read the 2nd IN_MODIFY event
119	 */
120	errno = 0;
121	len = read(fd_notify, event_buf, EVENT_BUF_LEN);
122	SAFE_CLOSE(fd_notify);
123	if (len < 0 && errno == EAGAIN) {
124		/* Treat no event same as we treat IN_IGNORED */
125		event->mask = IN_IGNORED;
126	} else if (len < (int)sizeof(*event)) {
127		tst_res(TFAIL | TERRNO, "Failed to read events");
128		return;
129	}
130
131	if (event->mask == IN_MODIFY) {
132		if (tc->expect_events > 1)
133			tst_res(TPASS, "Got 2nd event as expected");
134		else
135			tst_res(TFAIL, "Got unexpected 2nd event");
136	} else if (event->mask == IN_IGNORED) {
137		if (tc->expect_events == 1)
138			tst_res(TPASS, "Got no more events as expected");
139		else
140			tst_res(TFAIL, "Got only one event (expected %d)",
141					tc->expect_events);
142	} else {
143		tst_res(TFAIL, "Got unexpected event 0x%x",
144				event->mask);
145	}
146}
147
148static void cleanup(void)
149{
150	if (fd_notify > 0)
151		SAFE_CLOSE(fd_notify);
152}
153
154static struct tst_test test = {
155	.max_runtime = 10,
156	.needs_tmpdir = 1,
157	.cleanup = cleanup,
158	.test = verify_inotify,
159	.tcnt = ARRAY_SIZE(tcases),
160	.tags = (const struct tst_tag[]) {
161		{"linux-git", "a32e697cda27"},
162		{}
163	},
164};
165
166#else
167	TST_TEST_TCONF("system doesn't have required inotify support");
168#endif
169