1 /*
2  * Copyright (C) 2013-2021 Canonical, Ltd.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
17  *
18  * This code is a complete clean re-write of the stress tool by
19  * Colin Ian King <colin.king@canonical.com> and attempts to be
20  * backwardly compatible with the stress tool by Amos Waterland
21  * <apw@rossby.metr.ou.edu> but has more stress tests and more
22  * functionality.
23  *
24  */
25 #include "stress-ng.h"
26 
27 static const stress_help_t help[] = {
28 	{ NULL,	"sendfile N",	   "start N workers exercising sendfile" },
29 	{ NULL,	"sendfile-ops N",  "stop after N bogo sendfile operations" },
30 	{ NULL,	"sendfile-size N", "size of data to be sent with sendfile" },
31 	{ NULL,	NULL,		   NULL }
32 };
33 
stress_set_sendfile_size(const char * opt)34 static int stress_set_sendfile_size(const char *opt)
35 {
36 	uint64_t sendfile_size;
37 
38 	sendfile_size = stress_get_uint64_byte(opt);
39 	stress_check_range_bytes("sendfile-size", sendfile_size,
40 		MIN_SENDFILE_SIZE, MAX_SENDFILE_SIZE);
41 	return stress_set_setting("sendfile-size", TYPE_ID_UINT64, &sendfile_size);
42 }
43 
44 static const stress_opt_set_func_t opt_set_funcs[] = {
45 	{ OPT_sendfile_size,	stress_set_sendfile_size },
46 	{ 0,			NULL }
47 };
48 
49 #if defined(HAVE_SYS_SENDFILE_H) &&	\
50     NEED_GLIBC(2,1,0)
51 
52 /*
53  *  stress_sendfile
54  *	stress reading of a temp file and writing to /dev/null via sendfile
55  */
stress_sendfile(const stress_args_t * args)56 static int stress_sendfile(const stress_args_t *args)
57 {
58 	char filename[PATH_MAX];
59 	int i = 0, fdin, fdout, ret, bad_fd, rc = EXIT_SUCCESS;
60 	size_t sz;
61 	int64_t sendfile_size = DEFAULT_SENDFILE_SIZE;
62 
63 	if (!stress_get_setting("sendfile-size", &sendfile_size)) {
64 		if (g_opt_flags & OPT_FLAGS_MAXIMIZE)
65 			sendfile_size = MAX_SENDFILE_SIZE;
66 		if (g_opt_flags & OPT_FLAGS_MINIMIZE)
67 			sendfile_size = MIN_SENDFILE_SIZE;
68 	}
69 	sz = (size_t)sendfile_size;
70 
71 	ret = stress_temp_dir_mk_args(args);
72 	if (ret < 0)
73 		return exit_status(-ret);
74 
75 	(void)stress_temp_filename_args(args,
76 		filename, sizeof(filename), stress_mwc32());
77 
78 	if ((fdin = open(filename, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR)) < 0) {
79 		rc = exit_status(errno);
80 		pr_fail("%s: open %s failed, errno=%d (%s)\n",
81 			args->name, filename, errno, strerror(errno));
82 		goto dir_out;
83 	}
84 #if defined(HAVE_POSIX_FALLOCATE)
85 	ret = posix_fallocate(fdin, (off_t)0, (off_t)sz);
86 #else
87 	ret = shim_fallocate(fdin, 0, (off_t)0, (off_t)sz);
88 #endif
89 	if (ret < 0) {
90 		rc = exit_status(errno);
91 		pr_fail("%s: fallocate failed, errno=%d (%s)\n",
92 			args->name, errno, strerror(errno));
93 		goto dir_out;
94 	}
95 	(void)close(fdin);
96 	if ((fdin = open(filename, O_RDONLY)) < 0) {
97 		rc = exit_status(errno);
98 		pr_fail("%s: open %s failed, errno=%d (%s)\n",
99 			args->name, filename, errno, strerror(errno));
100 		goto dir_out;
101 	}
102 
103 	if ((fdout = open("/dev/null", O_WRONLY)) < 0) {
104 		pr_fail("%s: open /dev/null failed, errno=%d (%s)\n",
105 			args->name, errno, strerror(errno));
106 		rc = EXIT_FAILURE;
107 		goto close_in;
108 	}
109 
110 	bad_fd = stress_get_bad_fd();
111 
112 	stress_set_proc_state(args->name, STRESS_STATE_RUN);
113 
114 	do {
115 		off_t offset = 0;
116 
117 		if (sendfile(fdout, fdin, &offset, sz) < 0) {
118 			if (errno == ENOSYS) {
119 				if (args->instance == 0)
120 					pr_inf_skip("%s: skipping stressor, sendfile not implemented\n",
121 						args->name);
122 				rc = EXIT_NOT_IMPLEMENTED;
123 				goto close_out;
124 			}
125 			if (errno == EINTR)
126 				continue;
127 			pr_fail("%s: sendfile failed, errno=%d (%s)\n",
128 				args->name, errno, strerror(errno));
129 			rc = EXIT_FAILURE;
130 			goto close_out;
131 		}
132 
133 		/* Periodically perform some unusual sendfile calls */
134 		if ((i++ & 0xff) == 0) {
135 			/* Exercise with invalid destination fd */
136 			offset = 0;
137 			(void)sendfile(bad_fd, fdin, &offset, sz);
138 
139 			/* Exercise with invalid source fd */
140 			offset = 0;
141 			(void)sendfile(fdout, bad_fd, &offset, sz);
142 
143 			/* Exercise with invalid offset */
144 			offset = -1;
145 			(void)sendfile(fdout, fdin, &offset, sz);
146 
147 			/* Exercise with invalid size */
148 			offset = 0;
149 			(void)sendfile(fdout, fdin, &offset, (size_t)-1);
150 
151 			/* Exercise with zero size (should work, no-op) */
152 			offset = 0;
153 			(void)sendfile(fdout, fdin, &offset, 0);
154 
155 			/* Exercise with read-only destination (EBADF) */
156 			offset = 0;
157 			(void)sendfile(fdin, fdin, &offset, sz);
158 
159 			/* Exercise with write-only source (EBADF) */
160 			offset = 0;
161 			(void)sendfile(fdout, fdout, &offset, sz);
162 
163 			/* Exercise truncated read */
164 			offset = (off_t)(sz - 1);
165 			(void)sendfile(fdout, fdin, &offset, sz);
166 		}
167 		inc_counter(args);
168 	} while (keep_stressing(args));
169 
170 close_out:
171 	stress_set_proc_state(args->name, STRESS_STATE_DEINIT);
172 	(void)close(fdout);
173 close_in:
174 	stress_set_proc_state(args->name, STRESS_STATE_DEINIT);
175 	(void)close(fdin);
176 	(void)unlink(filename);
177 dir_out:
178 	stress_set_proc_state(args->name, STRESS_STATE_DEINIT);
179 	(void)stress_temp_dir_rm_args(args);
180 
181 	return rc;
182 }
183 
184 stressor_info_t stress_sendfile_info = {
185 	.stressor = stress_sendfile,
186 	.class = CLASS_PIPE_IO | CLASS_OS,
187 	.opt_set_funcs = opt_set_funcs,
188 	.help = help
189 };
190 #else
191 stressor_info_t stress_sendfile_info = {
192 	.stressor = stress_not_implemented,
193 	.class = CLASS_PIPE_IO | CLASS_OS,
194 	.opt_set_funcs = opt_set_funcs,
195 	.help = help
196 };
197 #endif
198