xref: /openbmc/linux/drivers/net/netdevsim/health.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019 Mellanox Technologies. All rights reserved */
3 
4 #include <linux/debugfs.h>
5 #include <linux/err.h>
6 #include <linux/kernel.h>
7 #include <linux/slab.h>
8 
9 #include "netdevsim.h"
10 
11 static int
12 nsim_dev_empty_reporter_dump(struct devlink_health_reporter *reporter,
13 			     struct devlink_fmsg *fmsg, void *priv_ctx,
14 			     struct netlink_ext_ack *extack)
15 {
16 	return 0;
17 }
18 
19 static int
20 nsim_dev_empty_reporter_diagnose(struct devlink_health_reporter *reporter,
21 				 struct devlink_fmsg *fmsg,
22 				 struct netlink_ext_ack *extack)
23 {
24 	return 0;
25 }
26 
27 static const
28 struct devlink_health_reporter_ops nsim_dev_empty_reporter_ops = {
29 	.name = "empty",
30 	.dump = nsim_dev_empty_reporter_dump,
31 	.diagnose = nsim_dev_empty_reporter_diagnose,
32 };
33 
34 struct nsim_dev_dummy_reporter_ctx {
35 	char *break_msg;
36 };
37 
38 static int
39 nsim_dev_dummy_reporter_recover(struct devlink_health_reporter *reporter,
40 				void *priv_ctx,
41 				struct netlink_ext_ack *extack)
42 {
43 	struct nsim_dev_health *health = devlink_health_reporter_priv(reporter);
44 	struct nsim_dev_dummy_reporter_ctx *ctx = priv_ctx;
45 
46 	if (health->fail_recover) {
47 		/* For testing purposes, user set debugfs fail_recover
48 		 * value to true. Fail right away.
49 		 */
50 		NL_SET_ERR_MSG_MOD(extack, "User setup the recover to fail for testing purposes");
51 		return -EINVAL;
52 	}
53 	if (ctx) {
54 		kfree(health->recovered_break_msg);
55 		health->recovered_break_msg = kstrdup(ctx->break_msg,
56 						      GFP_KERNEL);
57 		if (!health->recovered_break_msg)
58 			return -ENOMEM;
59 	}
60 	return 0;
61 }
62 
63 static int nsim_dev_dummy_fmsg_put(struct devlink_fmsg *fmsg, u32 binary_len)
64 {
65 	char *binary;
66 	int err;
67 	int i;
68 
69 	err = devlink_fmsg_bool_pair_put(fmsg, "test_bool", true);
70 	if (err)
71 		return err;
72 	err = devlink_fmsg_u8_pair_put(fmsg, "test_u8", 1);
73 	if (err)
74 		return err;
75 	err = devlink_fmsg_u32_pair_put(fmsg, "test_u32", 3);
76 	if (err)
77 		return err;
78 	err = devlink_fmsg_u64_pair_put(fmsg, "test_u64", 4);
79 	if (err)
80 		return err;
81 	err = devlink_fmsg_string_pair_put(fmsg, "test_string", "somestring");
82 	if (err)
83 		return err;
84 
85 	binary = kmalloc(binary_len, GFP_KERNEL | __GFP_NOWARN);
86 	if (!binary)
87 		return -ENOMEM;
88 	get_random_bytes(binary, binary_len);
89 	err = devlink_fmsg_binary_pair_put(fmsg, "test_binary", binary, binary_len);
90 	kfree(binary);
91 	if (err)
92 		return err;
93 
94 	err = devlink_fmsg_pair_nest_start(fmsg, "test_nest");
95 	if (err)
96 		return err;
97 	err = devlink_fmsg_obj_nest_start(fmsg);
98 	if (err)
99 		return err;
100 	err = devlink_fmsg_bool_pair_put(fmsg, "nested_test_bool", false);
101 	if (err)
102 		return err;
103 	err = devlink_fmsg_u8_pair_put(fmsg, "nested_test_u8", false);
104 	if (err)
105 		return err;
106 	err = devlink_fmsg_obj_nest_end(fmsg);
107 	if (err)
108 		return err;
109 	err = devlink_fmsg_pair_nest_end(fmsg);
110 	if (err)
111 		return err;
112 
113 	err = devlink_fmsg_arr_pair_nest_end(fmsg);
114 	if (err)
115 		return err;
116 
117 	err = devlink_fmsg_arr_pair_nest_start(fmsg, "test_u32_array");
118 	if (err)
119 		return err;
120 	for (i = 0; i < 10; i++) {
121 		err = devlink_fmsg_u32_put(fmsg, i);
122 		if (err)
123 			return err;
124 	}
125 	err = devlink_fmsg_arr_pair_nest_end(fmsg);
126 	if (err)
127 		return err;
128 
129 	err = devlink_fmsg_arr_pair_nest_start(fmsg, "test_array_of_objects");
130 	if (err)
131 		return err;
132 	for (i = 0; i < 10; i++) {
133 		err = devlink_fmsg_obj_nest_start(fmsg);
134 		if (err)
135 			return err;
136 		err = devlink_fmsg_bool_pair_put(fmsg,
137 						 "in_array_nested_test_bool",
138 						 false);
139 		if (err)
140 			return err;
141 		err = devlink_fmsg_u8_pair_put(fmsg,
142 					       "in_array_nested_test_u8",
143 					       i);
144 		if (err)
145 			return err;
146 		err = devlink_fmsg_obj_nest_end(fmsg);
147 		if (err)
148 			return err;
149 	}
150 	return devlink_fmsg_arr_pair_nest_end(fmsg);
151 }
152 
153 static int
154 nsim_dev_dummy_reporter_dump(struct devlink_health_reporter *reporter,
155 			     struct devlink_fmsg *fmsg, void *priv_ctx,
156 			     struct netlink_ext_ack *extack)
157 {
158 	struct nsim_dev_health *health = devlink_health_reporter_priv(reporter);
159 	struct nsim_dev_dummy_reporter_ctx *ctx = priv_ctx;
160 	int err;
161 
162 	if (ctx) {
163 		err = devlink_fmsg_string_pair_put(fmsg, "break_message",
164 						   ctx->break_msg);
165 		if (err)
166 			return err;
167 	}
168 	return nsim_dev_dummy_fmsg_put(fmsg, health->binary_len);
169 }
170 
171 static int
172 nsim_dev_dummy_reporter_diagnose(struct devlink_health_reporter *reporter,
173 				 struct devlink_fmsg *fmsg,
174 				 struct netlink_ext_ack *extack)
175 {
176 	struct nsim_dev_health *health = devlink_health_reporter_priv(reporter);
177 	int err;
178 
179 	if (health->recovered_break_msg) {
180 		err = devlink_fmsg_string_pair_put(fmsg,
181 						   "recovered_break_message",
182 						   health->recovered_break_msg);
183 		if (err)
184 			return err;
185 	}
186 	return nsim_dev_dummy_fmsg_put(fmsg, health->binary_len);
187 }
188 
189 static const
190 struct devlink_health_reporter_ops nsim_dev_dummy_reporter_ops = {
191 	.name = "dummy",
192 	.recover = nsim_dev_dummy_reporter_recover,
193 	.dump = nsim_dev_dummy_reporter_dump,
194 	.diagnose = nsim_dev_dummy_reporter_diagnose,
195 };
196 
197 static ssize_t nsim_dev_health_break_write(struct file *file,
198 					   const char __user *data,
199 					   size_t count, loff_t *ppos)
200 {
201 	struct nsim_dev_health *health = file->private_data;
202 	struct nsim_dev_dummy_reporter_ctx ctx;
203 	char *break_msg;
204 	int err;
205 
206 	break_msg = memdup_user_nul(data, count);
207 	if (IS_ERR(break_msg))
208 		return PTR_ERR(break_msg);
209 
210 	if (break_msg[count - 1] == '\n')
211 		break_msg[count - 1] = '\0';
212 
213 	ctx.break_msg = break_msg;
214 	err = devlink_health_report(health->dummy_reporter, break_msg, &ctx);
215 	if (err)
216 		goto out;
217 
218 out:
219 	kfree(break_msg);
220 	return err ?: count;
221 }
222 
223 static const struct file_operations nsim_dev_health_break_fops = {
224 	.open = simple_open,
225 	.write = nsim_dev_health_break_write,
226 	.llseek = generic_file_llseek,
227 	.owner = THIS_MODULE,
228 };
229 
230 int nsim_dev_health_init(struct nsim_dev *nsim_dev, struct devlink *devlink)
231 {
232 	struct nsim_dev_health *health = &nsim_dev->health;
233 	int err;
234 
235 	health->empty_reporter =
236 		devlink_health_reporter_create(devlink,
237 					       &nsim_dev_empty_reporter_ops,
238 					       0, health);
239 	if (IS_ERR(health->empty_reporter))
240 		return PTR_ERR(health->empty_reporter);
241 
242 	health->dummy_reporter =
243 		devlink_health_reporter_create(devlink,
244 					       &nsim_dev_dummy_reporter_ops,
245 					       0, health);
246 	if (IS_ERR(health->dummy_reporter)) {
247 		err = PTR_ERR(health->dummy_reporter);
248 		goto err_empty_reporter_destroy;
249 	}
250 
251 	health->ddir = debugfs_create_dir("health", nsim_dev->ddir);
252 	if (IS_ERR(health->ddir)) {
253 		err = PTR_ERR(health->ddir);
254 		goto err_dummy_reporter_destroy;
255 	}
256 
257 	health->recovered_break_msg = NULL;
258 	debugfs_create_file("break_health", 0200, health->ddir, health,
259 			    &nsim_dev_health_break_fops);
260 	health->binary_len = 16;
261 	debugfs_create_u32("binary_len", 0600, health->ddir,
262 			   &health->binary_len);
263 	health->fail_recover = false;
264 	debugfs_create_bool("fail_recover", 0600, health->ddir,
265 			    &health->fail_recover);
266 	return 0;
267 
268 err_dummy_reporter_destroy:
269 	devlink_health_reporter_destroy(health->dummy_reporter);
270 err_empty_reporter_destroy:
271 	devlink_health_reporter_destroy(health->empty_reporter);
272 	return err;
273 }
274 
275 void nsim_dev_health_exit(struct nsim_dev *nsim_dev)
276 {
277 	struct nsim_dev_health *health = &nsim_dev->health;
278 
279 	debugfs_remove_recursive(health->ddir);
280 	kfree(health->recovered_break_msg);
281 	devlink_health_reporter_destroy(health->dummy_reporter);
282 	devlink_health_reporter_destroy(health->empty_reporter);
283 }
284