xref: /dpdk/drivers/net/failsafe/failsafe_args.c (revision f665790a5dbad7b645ff46f31d65e977324e7bfc)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright 2017 6WIND S.A.
3  * Copyright 2017 Mellanox Technologies, Ltd
4  */
5 
6 #include <fcntl.h>
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <unistd.h>
11 #include <errno.h>
12 
13 #include <rte_debug.h>
14 #include <rte_devargs.h>
15 #include <rte_malloc.h>
16 #include <rte_kvargs.h>
17 #include <rte_string_fns.h>
18 
19 #include "failsafe_private.h"
20 
21 /* Callback used when a new device is found in devargs */
22 typedef int (parse_cb)(struct rte_eth_dev *dev, const char *params,
23 		uint8_t head);
24 
25 uint64_t failsafe_hotplug_poll = FAILSAFE_HOTPLUG_DEFAULT_TIMEOUT_MS;
26 int failsafe_mac_from_arg;
27 
28 static const char * const pmd_failsafe_init_parameters[] = {
29 	PMD_FAILSAFE_HOTPLUG_POLL_KVARG,
30 	PMD_FAILSAFE_MAC_KVARG,
31 	NULL,
32 };
33 
34 /*
35  * input: text.
36  * output: 0: if text[0] != '(',
37  *         0: if there are no corresponding ')'
38  *         n: distance to corresponding ')' otherwise
39  */
40 static size_t
41 closing_paren(const char *text)
42 {
43 	int nb_open = 0;
44 	size_t i = 0;
45 
46 	while (text[i] != '\0') {
47 		if (text[i] == '(')
48 			nb_open++;
49 		if (text[i] == ')')
50 			nb_open--;
51 		if (nb_open == 0)
52 			return i;
53 		i++;
54 	}
55 	return 0;
56 }
57 
58 static int
59 fs_parse_device(struct sub_device *sdev, char *args)
60 {
61 	struct rte_devargs *d;
62 	int ret;
63 
64 	d = &sdev->devargs;
65 	DEBUG("%s", args);
66 	ret = rte_devargs_parse(d, args);
67 	if (ret) {
68 		DEBUG("devargs parsing failed with code %d", ret);
69 		return ret;
70 	}
71 	sdev->bus = d->bus;
72 	sdev->state = DEV_PARSED;
73 	return 0;
74 }
75 
76 static void
77 fs_sanitize_cmdline(char *args)
78 {
79 	char *nl;
80 
81 	nl = strrchr(args, '\n');
82 	if (nl)
83 		nl[0] = '\0';
84 }
85 
86 static int
87 fs_execute_cmd(struct sub_device *sdev, char *cmdline)
88 {
89 	FILE *fp;
90 	/* store possible newline as well */
91 	char output[DEVARGS_MAXLEN + 1];
92 	size_t len;
93 	int ret;
94 
95 	RTE_ASSERT(cmdline != NULL || sdev->cmdline != NULL);
96 	if (sdev->cmdline == NULL) {
97 		size_t i;
98 
99 		len = strlen(cmdline) + 1;
100 		sdev->cmdline = calloc(1, len);
101 		if (sdev->cmdline == NULL) {
102 			ERROR("Command line allocation failed");
103 			return -ENOMEM;
104 		}
105 		strlcpy(sdev->cmdline, cmdline, len);
106 		/* Replace all commas in the command line by spaces */
107 		for (i = 0; i < len; i++)
108 			if (sdev->cmdline[i] == ',')
109 				sdev->cmdline[i] = ' ';
110 	}
111 	DEBUG("'%s'", sdev->cmdline);
112 	fp = popen(sdev->cmdline, "r");
113 	if (fp == NULL) {
114 		ret = -errno;
115 		ERROR("popen: %s", strerror(errno));
116 		return ret;
117 	}
118 	/* We only read one line */
119 	if (fgets(output, sizeof(output) - 1, fp) == NULL) {
120 		DEBUG("Could not read command output");
121 		ret = -ENODEV;
122 		goto ret_pclose;
123 	}
124 	fs_sanitize_cmdline(output);
125 	if (output[0] == '\0') {
126 		ret = -ENODEV;
127 		goto ret_pclose;
128 	}
129 	ret = fs_parse_device(sdev, output);
130 	if (ret)
131 		ERROR("Parsing device '%s' failed", output);
132 ret_pclose:
133 	if (pclose(fp) == -1)
134 		ERROR("pclose: %s", strerror(errno));
135 	return ret;
136 }
137 
138 static int
139 fs_read_fd(struct sub_device *sdev, char *fd_str)
140 {
141 	FILE *fp = NULL;
142 	int fd = -1;
143 	/* store possible newline as well */
144 	char output[DEVARGS_MAXLEN + 1];
145 	int err = -ENODEV;
146 	int oflags;
147 	int lcount;
148 
149 	RTE_ASSERT(fd_str != NULL || sdev->fd_str != NULL);
150 	if (sdev->fd_str == NULL) {
151 		sdev->fd_str = strdup(fd_str);
152 		if (sdev->fd_str == NULL) {
153 			ERROR("Command line allocation failed");
154 			return -ENOMEM;
155 		}
156 	}
157 	errno = 0;
158 	fd = strtol(fd_str, &fd_str, 0);
159 	if (errno || *fd_str || fd < 0) {
160 		ERROR("Parsing FD number failed");
161 		goto error;
162 	}
163 	/* Fiddle with copy of file descriptor */
164 	fd = dup(fd);
165 	if (fd == -1)
166 		goto error;
167 	oflags = fcntl(fd, F_GETFL);
168 	if (oflags == -1)
169 		goto error;
170 	if (fcntl(fd, F_SETFL, oflags | O_NONBLOCK) == -1)
171 		goto error;
172 	fp = fdopen(fd, "r");
173 	if (fp == NULL)
174 		goto error;
175 	fd = -1;
176 	/* Only take the last line into account */
177 	lcount = 0;
178 	while (fgets(output, sizeof(output), fp))
179 		++lcount;
180 	if (lcount == 0)
181 		goto error;
182 	else if (ferror(fp) && errno != EAGAIN)
183 		goto error;
184 	/* Line must end with a newline character */
185 	fs_sanitize_cmdline(output);
186 	if (output[0] == '\0')
187 		goto error;
188 	err = fs_parse_device(sdev, output);
189 	if (err)
190 		ERROR("Parsing device '%s' failed", output);
191 error:
192 	if (fp)
193 		fclose(fp);
194 	if (fd != -1)
195 		close(fd);
196 	return err;
197 }
198 
199 static int
200 fs_parse_device_param(struct rte_eth_dev *dev, const char *param,
201 		uint8_t head)
202 {
203 	struct fs_priv *priv;
204 	struct sub_device *sdev;
205 	char *args = NULL;
206 	size_t a, b;
207 	int ret;
208 
209 	priv = PRIV(dev);
210 	a = 0;
211 	b = 0;
212 	ret = 0;
213 	while  (param[b] != '(' &&
214 		param[b] != '\0')
215 		b++;
216 	a = b;
217 	b += closing_paren(&param[b]);
218 	if (a == b) {
219 		ERROR("Dangling parenthesis");
220 		return -EINVAL;
221 	}
222 	a += 1;
223 	args = strndup(&param[a], b - a);
224 	if (args == NULL) {
225 		ERROR("Not enough memory for parameter parsing");
226 		return -ENOMEM;
227 	}
228 	sdev = &priv->subs[head];
229 	if (strncmp(param, "dev", 3) == 0) {
230 		ret = fs_parse_device(sdev, args);
231 		if (ret)
232 			goto free_args;
233 	} else if (strncmp(param, "exec", 4) == 0) {
234 		ret = fs_execute_cmd(sdev, args);
235 		if (ret == -ENODEV) {
236 			DEBUG("Reading device info from command line failed");
237 			ret = 0;
238 		}
239 		if (ret)
240 			goto free_args;
241 	} else if (strncmp(param, "fd(", 3) == 0) {
242 		ret = fs_read_fd(sdev, args);
243 		if (ret == -ENODEV) {
244 			DEBUG("Reading device info from FD failed");
245 			ret = 0;
246 		}
247 		if (ret)
248 			goto free_args;
249 	} else {
250 		ERROR("Unrecognized device type: %.*s", (int)b, param);
251 		ret = -EINVAL;
252 	}
253 free_args:
254 	free(args);
255 	return ret;
256 }
257 
258 static int
259 fs_parse_sub_devices(parse_cb *cb,
260 		struct rte_eth_dev *dev, const char *params)
261 {
262 	size_t a, b;
263 	uint8_t head;
264 	int ret;
265 
266 	a = 0;
267 	head = 0;
268 	ret = 0;
269 	while (params[a] != '\0') {
270 		b = a;
271 		while (params[b] != '(' &&
272 		       params[b] != ',' &&
273 		       params[b] != '\0')
274 			b++;
275 		if (b == a) {
276 			ERROR("Invalid parameter");
277 			return -EINVAL;
278 		}
279 		if (params[b] == ',') {
280 			a = b + 1;
281 			continue;
282 		}
283 		if (params[b] == '(') {
284 			size_t start = b;
285 
286 			b += closing_paren(&params[b]);
287 			if (b == start) {
288 				ERROR("Dangling parenthesis");
289 				return -EINVAL;
290 			}
291 			ret = (*cb)(dev, &params[a], head);
292 			if (ret)
293 				return ret;
294 			head += 1;
295 			b += 1;
296 			if (params[b] == '\0')
297 				return 0;
298 		}
299 		a = b + 1;
300 	}
301 	return 0;
302 }
303 
304 static int
305 fs_remove_sub_devices_definition(char params[DEVARGS_MAXLEN])
306 {
307 	char buffer[DEVARGS_MAXLEN] = {0};
308 	size_t a, b;
309 	int i;
310 
311 	a = 0;
312 	i = 0;
313 	while (params[a] != '\0') {
314 		b = a;
315 		while (params[b] != '(' &&
316 		       params[b] != ',' &&
317 		       params[b] != '\0')
318 			b++;
319 		if (b == a) {
320 			ERROR("Invalid parameter");
321 			return -EINVAL;
322 		}
323 		if (params[b] == ',' || params[b] == '\0') {
324 			size_t len = b - a;
325 
326 			if (i > 0)
327 				len += 1;
328 			snprintf(&buffer[i], len + 1, "%s%s",
329 					i ? "," : "", &params[a]);
330 			i += len;
331 		} else if (params[b] == '(') {
332 			size_t start = b;
333 
334 			b += closing_paren(&params[b]);
335 			if (b == start)
336 				return -EINVAL;
337 			b += 1;
338 			if (params[b] == '\0')
339 				goto out;
340 		}
341 		a = b + 1;
342 	}
343 out:
344 	strlcpy(params, buffer, DEVARGS_MAXLEN);
345 	return 0;
346 }
347 
348 static int
349 fs_get_u64_arg(const char *key __rte_unused,
350 		const char *value, void *out)
351 {
352 	uint64_t *u64 = out;
353 	char *endptr = NULL;
354 
355 	if ((value == NULL) || (out == NULL))
356 		return -EINVAL;
357 	errno = 0;
358 	*u64 = strtoull(value, &endptr, 0);
359 	if (errno != 0)
360 		return -errno;
361 	if (endptr == value)
362 		return -1;
363 	return 0;
364 }
365 
366 static int
367 fs_get_mac_addr_arg(const char *key __rte_unused,
368 		const char *value, void *out)
369 {
370 	struct rte_ether_addr *ea = out;
371 
372 	if ((value == NULL) || (out == NULL))
373 		return -EINVAL;
374 
375 	return rte_ether_unformat_addr(value, ea);
376 }
377 
378 int
379 failsafe_args_parse(struct rte_eth_dev *dev, const char *params)
380 {
381 	struct fs_priv *priv;
382 	char mut_params[DEVARGS_MAXLEN] = "";
383 	struct rte_kvargs *kvlist = NULL;
384 	unsigned int arg_count;
385 	size_t n;
386 	int ret;
387 
388 	priv = PRIV(dev);
389 	ret = 0;
390 	priv->subs_tx = FAILSAFE_MAX_ETHPORTS;
391 	/* default parameters */
392 	n = strlcpy(mut_params, params, sizeof(mut_params));
393 	if (n >= sizeof(mut_params)) {
394 		ERROR("Parameter string too long (>=%zu)",
395 				sizeof(mut_params));
396 		return -ENOMEM;
397 	}
398 	ret = fs_parse_sub_devices(fs_parse_device_param,
399 				   dev, params);
400 	if (ret < 0)
401 		return ret;
402 	ret = fs_remove_sub_devices_definition(mut_params);
403 	if (ret < 0)
404 		return ret;
405 	if (strnlen(mut_params, sizeof(mut_params)) > 0) {
406 		kvlist = rte_kvargs_parse(mut_params,
407 				pmd_failsafe_init_parameters);
408 		if (kvlist == NULL) {
409 			ERROR("Error parsing parameters, usage:"
410 				PMD_FAILSAFE_PARAM_STRING);
411 			return -1;
412 		}
413 		/* PLUG_IN event poll timer */
414 		arg_count = rte_kvargs_count(kvlist,
415 				PMD_FAILSAFE_HOTPLUG_POLL_KVARG);
416 		if (arg_count == 1) {
417 			ret = rte_kvargs_process(kvlist,
418 					PMD_FAILSAFE_HOTPLUG_POLL_KVARG,
419 					&fs_get_u64_arg, &failsafe_hotplug_poll);
420 			if (ret < 0)
421 				goto free_kvlist;
422 		}
423 		/* MAC addr */
424 		arg_count = rte_kvargs_count(kvlist,
425 				PMD_FAILSAFE_MAC_KVARG);
426 		if (arg_count > 0) {
427 			ret = rte_kvargs_process(kvlist,
428 					PMD_FAILSAFE_MAC_KVARG,
429 					&fs_get_mac_addr_arg,
430 					&dev->data->mac_addrs[0]);
431 			if (ret < 0)
432 				goto free_kvlist;
433 
434 			failsafe_mac_from_arg = 1;
435 		}
436 	}
437 	PRIV(dev)->state = DEV_PARSED;
438 free_kvlist:
439 	rte_kvargs_free(kvlist);
440 	return ret;
441 }
442 
443 void
444 failsafe_args_free(struct rte_eth_dev *dev)
445 {
446 	struct sub_device *sdev;
447 	uint8_t i;
448 
449 	FOREACH_SUBDEV(sdev, i, dev) {
450 		free(sdev->cmdline);
451 		sdev->cmdline = NULL;
452 		free(sdev->fd_str);
453 		sdev->fd_str = NULL;
454 		rte_devargs_reset(&sdev->devargs);
455 	}
456 }
457 
458 static int
459 fs_count_device(struct rte_eth_dev *dev, const char *param,
460 		uint8_t head __rte_unused)
461 {
462 	size_t b = 0;
463 
464 	while  (param[b] != '(' &&
465 		param[b] != '\0')
466 		b++;
467 	if (strncmp(param, "dev", b) != 0 &&
468 	    strncmp(param, "exec", b) != 0 &&
469 	    strncmp(param, "fd(", b) != 0) {
470 		ERROR("Unrecognized device type: %.*s", (int)b, param);
471 		return -EINVAL;
472 	}
473 	PRIV(dev)->subs_tail += 1;
474 	return 0;
475 }
476 
477 int
478 failsafe_args_count_subdevice(struct rte_eth_dev *dev,
479 			const char *params)
480 {
481 	return fs_parse_sub_devices(fs_count_device,
482 				    dev, params);
483 }
484 
485 static int
486 fs_parse_sub_device(struct sub_device *sdev)
487 {
488 	struct rte_devargs *da;
489 	char devstr[DEVARGS_MAXLEN] = "";
490 
491 	da = &sdev->devargs;
492 	snprintf(devstr, sizeof(devstr), "%s,%s", da->name, da->args);
493 	return fs_parse_device(sdev, devstr);
494 }
495 
496 int
497 failsafe_args_parse_subs(struct rte_eth_dev *dev)
498 {
499 	struct sub_device *sdev;
500 	uint8_t i;
501 	int ret = 0;
502 
503 	FOREACH_SUBDEV(sdev, i, dev) {
504 		if (sdev->state >= DEV_PARSED)
505 			continue;
506 		if (sdev->cmdline)
507 			ret = fs_execute_cmd(sdev, sdev->cmdline);
508 		else if (sdev->fd_str)
509 			ret = fs_read_fd(sdev, sdev->fd_str);
510 		else
511 			ret = fs_parse_sub_device(sdev);
512 		if (ret == 0)
513 			sdev->state = DEV_PARSED;
514 	}
515 	return 0;
516 }
517