1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2020, Oracle and/or its affiliates.
4 *    Author: Alan Maguire <alan.maguire@oracle.com>
5 */
6
7#include <linux/debugfs.h>
8#include <linux/module.h>
9
10#include <kunit/test.h>
11#include <kunit/test-bug.h>
12
13#include "string-stream.h"
14#include "debugfs.h"
15
16#define KUNIT_DEBUGFS_ROOT             "kunit"
17#define KUNIT_DEBUGFS_RESULTS          "results"
18#define KUNIT_DEBUGFS_RUN              "run"
19
20/*
21 * Create a debugfs representation of test suites:
22 *
23 * Path						Semantics
24 * /sys/kernel/debug/kunit/<testsuite>/results	Show results of last run for
25 *						testsuite
26 * /sys/kernel/debug/kunit/<testsuite>/run	Write to this file to trigger
27 *						testsuite to run
28 *
29 */
30
31static struct dentry *debugfs_rootdir;
32
33void kunit_debugfs_cleanup(void)
34{
35	debugfs_remove_recursive(debugfs_rootdir);
36}
37
38void kunit_debugfs_init(void)
39{
40	if (!debugfs_rootdir)
41		debugfs_rootdir = debugfs_create_dir(KUNIT_DEBUGFS_ROOT, NULL);
42}
43
44static void debugfs_print_result(struct seq_file *seq, struct string_stream *log)
45{
46	struct string_stream_fragment *frag_container;
47
48	if (!log)
49		return;
50
51	/*
52	 * Walk the fragments so we don't need to allocate a temporary
53	 * buffer to hold the entire string.
54	 */
55	spin_lock(&log->lock);
56	list_for_each_entry(frag_container, &log->fragments, node)
57		seq_printf(seq, "%s", frag_container->fragment);
58	spin_unlock(&log->lock);
59}
60
61/*
62 * /sys/kernel/debug/kunit/<testsuite>/results shows all results for testsuite.
63 */
64static int debugfs_print_results(struct seq_file *seq, void *v)
65{
66	struct kunit_suite *suite = (struct kunit_suite *)seq->private;
67	enum kunit_status success;
68	struct kunit_case *test_case;
69
70	if (!suite)
71		return 0;
72
73	success = kunit_suite_has_succeeded(suite);
74
75	/* Print KTAP header so the debugfs log can be parsed as valid KTAP. */
76	seq_puts(seq, "KTAP version 1\n");
77	seq_puts(seq, "1..1\n");
78
79	/* Print suite header because it is not stored in the test logs. */
80	seq_puts(seq, KUNIT_SUBTEST_INDENT "KTAP version 1\n");
81	seq_printf(seq, KUNIT_SUBTEST_INDENT "# Subtest: %s\n", suite->name);
82	seq_printf(seq, KUNIT_SUBTEST_INDENT "1..%zd\n", kunit_suite_num_test_cases(suite));
83
84	kunit_suite_for_each_test_case(suite, test_case)
85		debugfs_print_result(seq, test_case->log);
86
87	debugfs_print_result(seq, suite->log);
88
89	seq_printf(seq, "%s %d %s\n",
90		   kunit_status_to_ok_not_ok(success), 1, suite->name);
91	return 0;
92}
93
94static int debugfs_release(struct inode *inode, struct file *file)
95{
96	return single_release(inode, file);
97}
98
99static int debugfs_results_open(struct inode *inode, struct file *file)
100{
101	struct kunit_suite *suite;
102
103	suite = (struct kunit_suite *)inode->i_private;
104
105	return single_open(file, debugfs_print_results, suite);
106}
107
108/*
109 * Print a usage message to the debugfs "run" file
110 * (/sys/kernel/debug/kunit/<testsuite>/run) if opened.
111 */
112static int debugfs_print_run(struct seq_file *seq, void *v)
113{
114	struct kunit_suite *suite = (struct kunit_suite *)seq->private;
115
116	seq_puts(seq, "Write to this file to trigger the test suite to run.\n");
117	seq_printf(seq, "usage: echo \"any string\" > /sys/kernel/debugfs/kunit/%s/run\n",
118			suite->name);
119	return 0;
120}
121
122/*
123 * The debugfs "run" file (/sys/kernel/debug/kunit/<testsuite>/run)
124 * contains no information. Write to the file to trigger the test suite
125 * to run.
126 */
127static int debugfs_run_open(struct inode *inode, struct file *file)
128{
129	struct kunit_suite *suite;
130
131	suite = (struct kunit_suite *)inode->i_private;
132
133	return single_open(file, debugfs_print_run, suite);
134}
135
136/*
137 * Trigger a test suite to run by writing to the suite's "run" debugfs
138 * file found at: /sys/kernel/debug/kunit/<testsuite>/run
139 *
140 * Note: what is written to this file will not be saved.
141 */
142static ssize_t debugfs_run(struct file *file,
143		const char __user *buf, size_t count, loff_t *ppos)
144{
145	struct inode *f_inode = file->f_inode;
146	struct kunit_suite *suite = (struct kunit_suite *) f_inode->i_private;
147
148	__kunit_test_suites_init(&suite, 1);
149
150	return count;
151}
152
153static const struct file_operations debugfs_results_fops = {
154	.open = debugfs_results_open,
155	.read = seq_read,
156	.llseek = seq_lseek,
157	.release = debugfs_release,
158};
159
160static const struct file_operations debugfs_run_fops = {
161	.open = debugfs_run_open,
162	.read = seq_read,
163	.write = debugfs_run,
164	.llseek = seq_lseek,
165	.release = debugfs_release,
166};
167
168void kunit_debugfs_create_suite(struct kunit_suite *suite)
169{
170	struct kunit_case *test_case;
171	struct string_stream *stream;
172
173	/* If suite log already allocated, do not create new debugfs files. */
174	if (suite->log)
175		return;
176
177	/*
178	 * Allocate logs before creating debugfs representation.
179	 * The suite->log and test_case->log pointer are expected to be NULL
180	 * if there isn't a log, so only set it if the log stream was created
181	 * successfully.
182	 */
183	stream = alloc_string_stream(GFP_KERNEL);
184	if (IS_ERR_OR_NULL(stream))
185		return;
186
187	string_stream_set_append_newlines(stream, true);
188	suite->log = stream;
189
190	kunit_suite_for_each_test_case(suite, test_case) {
191		stream = alloc_string_stream(GFP_KERNEL);
192		if (IS_ERR_OR_NULL(stream))
193			goto err;
194
195		string_stream_set_append_newlines(stream, true);
196		test_case->log = stream;
197	}
198
199	suite->debugfs = debugfs_create_dir(suite->name, debugfs_rootdir);
200
201	debugfs_create_file(KUNIT_DEBUGFS_RESULTS, S_IFREG | 0444,
202			    suite->debugfs,
203			    suite, &debugfs_results_fops);
204
205	/* Do not create file to re-run test if test runs on init */
206	if (!suite->is_init) {
207		debugfs_create_file(KUNIT_DEBUGFS_RUN, S_IFREG | 0644,
208				    suite->debugfs,
209				    suite, &debugfs_run_fops);
210	}
211	return;
212
213err:
214	string_stream_destroy(suite->log);
215	kunit_suite_for_each_test_case(suite, test_case)
216		string_stream_destroy(test_case->log);
217}
218
219void kunit_debugfs_destroy_suite(struct kunit_suite *suite)
220{
221	struct kunit_case *test_case;
222
223	debugfs_remove_recursive(suite->debugfs);
224	string_stream_destroy(suite->log);
225	kunit_suite_for_each_test_case(suite, test_case)
226		string_stream_destroy(test_case->log);
227}
228