xref: /dpdk/drivers/common/mlx5/linux/mlx5_common_os.c (revision 89813a522e68076e6f50ec18b075fa57cc5ae937)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright 2020 Mellanox Technologies, Ltd
3  */
4 
5 #include <unistd.h>
6 #include <string.h>
7 #include <stdio.h>
8 #ifdef RTE_IBVERBS_LINK_DLOPEN
9 #include <dlfcn.h>
10 #endif
11 #include <dirent.h>
12 #include <net/if.h>
13 
14 #include <rte_errno.h>
15 #include <rte_string_fns.h>
16 
17 #include "mlx5_common.h"
18 #include "mlx5_common_utils.h"
19 #include "mlx5_glue.h"
20 
21 #ifdef MLX5_GLUE
22 const struct mlx5_glue *mlx5_glue;
23 #endif
24 
25 /**
26  * Get PCI information by sysfs device path.
27  *
28  * @param dev_path
29  *   Pointer to device sysfs folder name.
30  * @param[out] pci_addr
31  *   PCI bus address output buffer.
32  *
33  * @return
34  *   0 on success, a negative errno value otherwise and rte_errno is set.
35  */
36 int
37 mlx5_dev_to_pci_addr(const char *dev_path,
38 		     struct rte_pci_addr *pci_addr)
39 {
40 	FILE *file;
41 	char line[32];
42 	int rc = -ENOENT;
43 	MKSTR(path, "%s/device/uevent", dev_path);
44 
45 	file = fopen(path, "rb");
46 	if (file == NULL) {
47 		rte_errno = errno;
48 		return -rte_errno;
49 	}
50 	while (fgets(line, sizeof(line), file) == line) {
51 		size_t len = strlen(line);
52 
53 		/* Truncate long lines. */
54 		if (len == (sizeof(line) - 1)) {
55 			while (line[(len - 1)] != '\n') {
56 				int ret = fgetc(file);
57 
58 				if (ret == EOF)
59 					goto exit;
60 				line[(len - 1)] = ret;
61 			}
62 			/* No match for long lines. */
63 			continue;
64 		}
65 		/* Extract information. */
66 		if (sscanf(line,
67 			   "PCI_SLOT_NAME="
68 			   "%" SCNx32 ":%" SCNx8 ":%" SCNx8 ".%" SCNx8 "\n",
69 			   &pci_addr->domain,
70 			   &pci_addr->bus,
71 			   &pci_addr->devid,
72 			   &pci_addr->function) == 4) {
73 			rc = 0;
74 			break;
75 		}
76 	}
77 exit:
78 	fclose(file);
79 	if (rc)
80 		rte_errno = -rc;
81 	return rc;
82 }
83 
84 /**
85  * Extract port name, as a number, from sysfs or netlink information.
86  *
87  * @param[in] port_name_in
88  *   String representing the port name.
89  * @param[out] port_info_out
90  *   Port information, including port name as a number and port name
91  *   type if recognized
92  *
93  * @return
94  *   port_name field set according to recognized name format.
95  */
96 void
97 mlx5_translate_port_name(const char *port_name_in,
98 			 struct mlx5_switch_info *port_info_out)
99 {
100 	char ctrl = 0, pf_c1, pf_c2, vf_c1, vf_c2, eol;
101 	char *end;
102 	int sc_items;
103 
104 	sc_items = sscanf(port_name_in, "%c%d",
105 			  &ctrl, &port_info_out->ctrl_num);
106 	if (sc_items == 2 && ctrl == 'c') {
107 		port_name_in++; /* 'c' */
108 		port_name_in += snprintf(NULL, 0, "%d",
109 					  port_info_out->ctrl_num);
110 	}
111 	/* Check for port-name as a string of the form pf0vf0 or pf0sf0 */
112 	sc_items = sscanf(port_name_in, "%c%c%d%c%c%d%c",
113 			  &pf_c1, &pf_c2, &port_info_out->pf_num,
114 			  &vf_c1, &vf_c2, &port_info_out->port_name, &eol);
115 	if (sc_items == 6 && pf_c1 == 'p' && pf_c2 == 'f') {
116 		if (vf_c1 == 'v' && vf_c2 == 'f') {
117 			/* Kernel ver >= 5.0 or OFED ver >= 4.6 */
118 			port_info_out->name_type =
119 					MLX5_PHYS_PORT_NAME_TYPE_PFVF;
120 			return;
121 		}
122 		if (vf_c1 == 's' && vf_c2 == 'f') {
123 			/* Kernel ver >= 5.11 or OFED ver >= 5.1 */
124 			port_info_out->name_type =
125 					MLX5_PHYS_PORT_NAME_TYPE_PFSF;
126 			return;
127 		}
128 	}
129 	/*
130 	 * Check for port-name as a string of the form p0
131 	 * (support kernel ver >= 5.0, or OFED ver >= 4.6).
132 	 */
133 	sc_items = sscanf(port_name_in, "%c%d%c",
134 			  &pf_c1, &port_info_out->port_name, &eol);
135 	if (sc_items == 2 && pf_c1 == 'p') {
136 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UPLINK;
137 		return;
138 	}
139 	/*
140 	 * Check for port-name as a string of the form pf0
141 	 * (support kernel ver >= 5.7 for HPF representor on BF).
142 	 */
143 	sc_items = sscanf(port_name_in, "%c%c%d%c",
144 			  &pf_c1, &pf_c2, &port_info_out->pf_num, &eol);
145 	if (sc_items == 3 && pf_c1 == 'p' && pf_c2 == 'f') {
146 		port_info_out->port_name = -1;
147 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_PFHPF;
148 		return;
149 	}
150 	/* Check for port-name as a number (support kernel ver < 5.0 */
151 	errno = 0;
152 	port_info_out->port_name = strtol(port_name_in, &end, 0);
153 	if (!errno &&
154 	    (size_t)(end - port_name_in) == strlen(port_name_in)) {
155 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_LEGACY;
156 		return;
157 	}
158 	port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UNKNOWN;
159 }
160 
161 /**
162  * Get kernel interface name from IB device path.
163  *
164  * @param[in] ibdev_path
165  *   Pointer to IB device path.
166  * @param[out] ifname
167  *   Interface name output buffer.
168  *
169  * @return
170  *   0 on success, a negative errno value otherwise and rte_errno is set.
171  */
172 int
173 mlx5_get_ifname_sysfs(const char *ibdev_path, char *ifname)
174 {
175 	DIR *dir;
176 	struct dirent *dent;
177 	unsigned int dev_type = 0;
178 	unsigned int dev_port_prev = ~0u;
179 	char match[IF_NAMESIZE] = "";
180 
181 	MLX5_ASSERT(ibdev_path);
182 	{
183 		MKSTR(path, "%s/device/net", ibdev_path);
184 
185 		dir = opendir(path);
186 		if (dir == NULL) {
187 			rte_errno = errno;
188 			return -rte_errno;
189 		}
190 	}
191 	while ((dent = readdir(dir)) != NULL) {
192 		char *name = dent->d_name;
193 		FILE *file;
194 		unsigned int dev_port;
195 		int r;
196 
197 		if ((name[0] == '.') &&
198 		    ((name[1] == '\0') ||
199 		     ((name[1] == '.') && (name[2] == '\0'))))
200 			continue;
201 
202 		MKSTR(path, "%s/device/net/%s/%s",
203 		      ibdev_path, name,
204 		      (dev_type ? "dev_id" : "dev_port"));
205 
206 		file = fopen(path, "rb");
207 		if (file == NULL) {
208 			if (errno != ENOENT)
209 				continue;
210 			/*
211 			 * Switch to dev_id when dev_port does not exist as
212 			 * is the case with Linux kernel versions < 3.15.
213 			 */
214 try_dev_id:
215 			match[0] = '\0';
216 			if (dev_type)
217 				break;
218 			dev_type = 1;
219 			dev_port_prev = ~0u;
220 			rewinddir(dir);
221 			continue;
222 		}
223 		r = fscanf(file, (dev_type ? "%x" : "%u"), &dev_port);
224 		fclose(file);
225 		if (r != 1)
226 			continue;
227 		/*
228 		 * Switch to dev_id when dev_port returns the same value for
229 		 * all ports. May happen when using a MOFED release older than
230 		 * 3.0 with a Linux kernel >= 3.15.
231 		 */
232 		if (dev_port == dev_port_prev)
233 			goto try_dev_id;
234 		dev_port_prev = dev_port;
235 		if (dev_port == 0)
236 			strlcpy(match, name, IF_NAMESIZE);
237 	}
238 	closedir(dir);
239 	if (match[0] == '\0') {
240 		rte_errno = ENOENT;
241 		return -rte_errno;
242 	}
243 	strncpy(ifname, match, IF_NAMESIZE);
244 	return 0;
245 }
246 
247 #ifdef MLX5_GLUE
248 
249 /**
250  * Suffix RTE_EAL_PMD_PATH with "-glue".
251  *
252  * This function performs a sanity check on RTE_EAL_PMD_PATH before
253  * suffixing its last component.
254  *
255  * @param buf[out]
256  *   Output buffer, should be large enough otherwise NULL is returned.
257  * @param size
258  *   Size of @p out.
259  *
260  * @return
261  *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
262  */
263 static char *
264 mlx5_glue_path(char *buf, size_t size)
265 {
266 	static const char *const bad[] = { "/", ".", "..", NULL };
267 	const char *path = RTE_EAL_PMD_PATH;
268 	size_t len = strlen(path);
269 	size_t off;
270 	int i;
271 
272 	while (len && path[len - 1] == '/')
273 		--len;
274 	for (off = len; off && path[off - 1] != '/'; --off)
275 		;
276 	for (i = 0; bad[i]; ++i)
277 		if (!strncmp(path + off, bad[i], (int)(len - off)))
278 			goto error;
279 	i = snprintf(buf, size, "%.*s-glue", (int)len, path);
280 	if (i == -1 || (size_t)i >= size)
281 		goto error;
282 	return buf;
283 error:
284 	RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
285 		" RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
286 		" re-configure DPDK");
287 	return NULL;
288 }
289 
290 static int
291 mlx5_glue_dlopen(void)
292 {
293 	char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
294 	void *handle = NULL;
295 
296 	char const *path[] = {
297 		/*
298 		 * A basic security check is necessary before trusting
299 		 * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
300 		 */
301 		(geteuid() == getuid() && getegid() == getgid() ?
302 		 getenv("MLX5_GLUE_PATH") : NULL),
303 		/*
304 		 * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
305 		 * variant, otherwise let dlopen() look up libraries on its
306 		 * own.
307 		 */
308 		(*RTE_EAL_PMD_PATH ?
309 		 mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
310 	};
311 	unsigned int i = 0;
312 	void **sym;
313 	const char *dlmsg;
314 
315 	while (!handle && i != RTE_DIM(path)) {
316 		const char *end;
317 		size_t len;
318 		int ret;
319 
320 		if (!path[i]) {
321 			++i;
322 			continue;
323 		}
324 		end = strpbrk(path[i], ":;");
325 		if (!end)
326 			end = path[i] + strlen(path[i]);
327 		len = end - path[i];
328 		ret = 0;
329 		do {
330 			char name[ret + 1];
331 
332 			ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
333 				       (int)len, path[i],
334 				       (!len || *(end - 1) == '/') ? "" : "/");
335 			if (ret == -1)
336 				break;
337 			if (sizeof(name) != (size_t)ret + 1)
338 				continue;
339 			DRV_LOG(DEBUG, "Looking for rdma-core glue as "
340 				"\"%s\"", name);
341 			handle = dlopen(name, RTLD_LAZY);
342 			break;
343 		} while (1);
344 		path[i] = end + 1;
345 		if (!*end)
346 			++i;
347 	}
348 	if (!handle) {
349 		rte_errno = EINVAL;
350 		dlmsg = dlerror();
351 		if (dlmsg)
352 			DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
353 		goto glue_error;
354 	}
355 	sym = dlsym(handle, "mlx5_glue");
356 	if (!sym || !*sym) {
357 		rte_errno = EINVAL;
358 		dlmsg = dlerror();
359 		if (dlmsg)
360 			DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
361 		goto glue_error;
362 	}
363 	mlx5_glue = *sym;
364 	return 0;
365 
366 glue_error:
367 	if (handle)
368 		dlclose(handle);
369 	return -1;
370 }
371 
372 #endif
373 
374 /**
375  * Initialization routine for run-time dependency on rdma-core.
376  */
377 void
378 mlx5_glue_constructor(void)
379 {
380 	/*
381 	 * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
382 	 * huge pages. Calling ibv_fork_init() during init allows
383 	 * applications to use fork() safely for purposes other than
384 	 * using this PMD, which is not supported in forked processes.
385 	 */
386 	setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
387 	/* Match the size of Rx completion entry to the size of a cacheline. */
388 	if (RTE_CACHE_LINE_SIZE == 128)
389 		setenv("MLX5_CQE_SIZE", "128", 0);
390 	/*
391 	 * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
392 	 * cleanup all the Verbs resources even when the device was removed.
393 	 */
394 	setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
395 
396 #ifdef MLX5_GLUE
397 	if (mlx5_glue_dlopen() != 0)
398 		goto glue_error;
399 #endif
400 
401 #ifdef RTE_LIBRTE_MLX5_DEBUG
402 	/* Glue structure must not contain any NULL pointers. */
403 	{
404 		unsigned int i;
405 
406 		for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
407 			MLX5_ASSERT(((const void *const *)mlx5_glue)[i]);
408 	}
409 #endif
410 	if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
411 		rte_errno = EINVAL;
412 		DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
413 			"required", mlx5_glue->version, MLX5_GLUE_VERSION);
414 		goto glue_error;
415 	}
416 	mlx5_glue->fork_init();
417 	return;
418 
419 glue_error:
420 	DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
421 		" run-time dependency on rdma-core libraries (libibverbs,"
422 		" libmlx5)");
423 	mlx5_glue = NULL;
424 }
425 
426