xref: /dpdk/drivers/common/mlx5/linux/mlx5_common_os.c (revision fda34680eb9abf53872bde66e119f4c0288fd62f)
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 	MKSTR(path, "%s/device/uevent", dev_path);
43 
44 	file = fopen(path, "rb");
45 	if (file == NULL) {
46 		rte_errno = errno;
47 		return -rte_errno;
48 	}
49 	while (fgets(line, sizeof(line), file) == line) {
50 		size_t len = strlen(line);
51 		int ret;
52 
53 		/* Truncate long lines. */
54 		if (len == (sizeof(line) - 1))
55 			while (line[(len - 1)] != '\n') {
56 				ret = fgetc(file);
57 				if (ret == EOF)
58 					break;
59 				line[(len - 1)] = ret;
60 			}
61 		/* Extract information. */
62 		if (sscanf(line,
63 			   "PCI_SLOT_NAME="
64 			   "%" SCNx32 ":%" SCNx8 ":%" SCNx8 ".%" SCNx8 "\n",
65 			   &pci_addr->domain,
66 			   &pci_addr->bus,
67 			   &pci_addr->devid,
68 			   &pci_addr->function) == 4) {
69 			break;
70 		}
71 	}
72 	fclose(file);
73 	return 0;
74 }
75 
76 /**
77  * Extract port name, as a number, from sysfs or netlink information.
78  *
79  * @param[in] port_name_in
80  *   String representing the port name.
81  * @param[out] port_info_out
82  *   Port information, including port name as a number and port name
83  *   type if recognized
84  *
85  * @return
86  *   port_name field set according to recognized name format.
87  */
88 void
89 mlx5_translate_port_name(const char *port_name_in,
90 			 struct mlx5_switch_info *port_info_out)
91 {
92 	char pf_c1, pf_c2, vf_c1, vf_c2, eol;
93 	char *end;
94 	int sc_items;
95 
96 	/*
97 	 * Check for port-name as a string of the form pf0vf0
98 	 * (support kernel ver >= 5.0 or OFED ver >= 4.6).
99 	 */
100 	sc_items = sscanf(port_name_in, "%c%c%d%c%c%d%c",
101 			  &pf_c1, &pf_c2, &port_info_out->pf_num,
102 			  &vf_c1, &vf_c2, &port_info_out->port_name, &eol);
103 	if (sc_items == 6 &&
104 	    pf_c1 == 'p' && pf_c2 == 'f' &&
105 	    vf_c1 == 'v' && vf_c2 == 'f') {
106 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_PFVF;
107 		return;
108 	}
109 	/*
110 	 * Check for port-name as a string of the form p0
111 	 * (support kernel ver >= 5.0, or OFED ver >= 4.6).
112 	 */
113 	sc_items = sscanf(port_name_in, "%c%d%c",
114 			  &pf_c1, &port_info_out->port_name, &eol);
115 	if (sc_items == 2 && pf_c1 == 'p') {
116 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UPLINK;
117 		return;
118 	}
119 	/*
120 	 * Check for port-name as a string of the form pf0
121 	 * (support kernel ver >= 5.7 for HPF representor on BF).
122 	 */
123 	sc_items = sscanf(port_name_in, "%c%c%d%c",
124 			  &pf_c1, &pf_c2, &port_info_out->pf_num, &eol);
125 	if (sc_items == 3 && pf_c1 == 'p' && pf_c2 == 'f') {
126 		port_info_out->port_name = -1;
127 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_PFHPF;
128 		return;
129 	}
130 	/* Check for port-name as a number (support kernel ver < 5.0 */
131 	errno = 0;
132 	port_info_out->port_name = strtol(port_name_in, &end, 0);
133 	if (!errno &&
134 	    (size_t)(end - port_name_in) == strlen(port_name_in)) {
135 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_LEGACY;
136 		return;
137 	}
138 	port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UNKNOWN;
139 }
140 
141 /**
142  * Get kernel interface name from IB device path.
143  *
144  * @param[in] ibdev_path
145  *   Pointer to IB device path.
146  * @param[out] ifname
147  *   Interface name output buffer.
148  *
149  * @return
150  *   0 on success, a negative errno value otherwise and rte_errno is set.
151  */
152 int
153 mlx5_get_ifname_sysfs(const char *ibdev_path, char *ifname)
154 {
155 	DIR *dir;
156 	struct dirent *dent;
157 	unsigned int dev_type = 0;
158 	unsigned int dev_port_prev = ~0u;
159 	char match[IF_NAMESIZE] = "";
160 
161 	MLX5_ASSERT(ibdev_path);
162 	{
163 		MKSTR(path, "%s/device/net", ibdev_path);
164 
165 		dir = opendir(path);
166 		if (dir == NULL) {
167 			rte_errno = errno;
168 			return -rte_errno;
169 		}
170 	}
171 	while ((dent = readdir(dir)) != NULL) {
172 		char *name = dent->d_name;
173 		FILE *file;
174 		unsigned int dev_port;
175 		int r;
176 
177 		if ((name[0] == '.') &&
178 		    ((name[1] == '\0') ||
179 		     ((name[1] == '.') && (name[2] == '\0'))))
180 			continue;
181 
182 		MKSTR(path, "%s/device/net/%s/%s",
183 		      ibdev_path, name,
184 		      (dev_type ? "dev_id" : "dev_port"));
185 
186 		file = fopen(path, "rb");
187 		if (file == NULL) {
188 			if (errno != ENOENT)
189 				continue;
190 			/*
191 			 * Switch to dev_id when dev_port does not exist as
192 			 * is the case with Linux kernel versions < 3.15.
193 			 */
194 try_dev_id:
195 			match[0] = '\0';
196 			if (dev_type)
197 				break;
198 			dev_type = 1;
199 			dev_port_prev = ~0u;
200 			rewinddir(dir);
201 			continue;
202 		}
203 		r = fscanf(file, (dev_type ? "%x" : "%u"), &dev_port);
204 		fclose(file);
205 		if (r != 1)
206 			continue;
207 		/*
208 		 * Switch to dev_id when dev_port returns the same value for
209 		 * all ports. May happen when using a MOFED release older than
210 		 * 3.0 with a Linux kernel >= 3.15.
211 		 */
212 		if (dev_port == dev_port_prev)
213 			goto try_dev_id;
214 		dev_port_prev = dev_port;
215 		if (dev_port == 0)
216 			strlcpy(match, name, IF_NAMESIZE);
217 	}
218 	closedir(dir);
219 	if (match[0] == '\0') {
220 		rte_errno = ENOENT;
221 		return -rte_errno;
222 	}
223 	strncpy(ifname, match, IF_NAMESIZE);
224 	return 0;
225 }
226 
227 #ifdef MLX5_GLUE
228 
229 /**
230  * Suffix RTE_EAL_PMD_PATH with "-glue".
231  *
232  * This function performs a sanity check on RTE_EAL_PMD_PATH before
233  * suffixing its last component.
234  *
235  * @param buf[out]
236  *   Output buffer, should be large enough otherwise NULL is returned.
237  * @param size
238  *   Size of @p out.
239  *
240  * @return
241  *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
242  */
243 static char *
244 mlx5_glue_path(char *buf, size_t size)
245 {
246 	static const char *const bad[] = { "/", ".", "..", NULL };
247 	const char *path = RTE_EAL_PMD_PATH;
248 	size_t len = strlen(path);
249 	size_t off;
250 	int i;
251 
252 	while (len && path[len - 1] == '/')
253 		--len;
254 	for (off = len; off && path[off - 1] != '/'; --off)
255 		;
256 	for (i = 0; bad[i]; ++i)
257 		if (!strncmp(path + off, bad[i], (int)(len - off)))
258 			goto error;
259 	i = snprintf(buf, size, "%.*s-glue", (int)len, path);
260 	if (i == -1 || (size_t)i >= size)
261 		goto error;
262 	return buf;
263 error:
264 	RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
265 		" RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
266 		" re-configure DPDK");
267 	return NULL;
268 }
269 
270 static int
271 mlx5_glue_dlopen(void)
272 {
273 	char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
274 	void *handle = NULL;
275 
276 	char const *path[] = {
277 		/*
278 		 * A basic security check is necessary before trusting
279 		 * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
280 		 */
281 		(geteuid() == getuid() && getegid() == getgid() ?
282 		 getenv("MLX5_GLUE_PATH") : NULL),
283 		/*
284 		 * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
285 		 * variant, otherwise let dlopen() look up libraries on its
286 		 * own.
287 		 */
288 		(*RTE_EAL_PMD_PATH ?
289 		 mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
290 	};
291 	unsigned int i = 0;
292 	void **sym;
293 	const char *dlmsg;
294 
295 	while (!handle && i != RTE_DIM(path)) {
296 		const char *end;
297 		size_t len;
298 		int ret;
299 
300 		if (!path[i]) {
301 			++i;
302 			continue;
303 		}
304 		end = strpbrk(path[i], ":;");
305 		if (!end)
306 			end = path[i] + strlen(path[i]);
307 		len = end - path[i];
308 		ret = 0;
309 		do {
310 			char name[ret + 1];
311 
312 			ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
313 				       (int)len, path[i],
314 				       (!len || *(end - 1) == '/') ? "" : "/");
315 			if (ret == -1)
316 				break;
317 			if (sizeof(name) != (size_t)ret + 1)
318 				continue;
319 			DRV_LOG(DEBUG, "Looking for rdma-core glue as "
320 				"\"%s\"", name);
321 			handle = dlopen(name, RTLD_LAZY);
322 			break;
323 		} while (1);
324 		path[i] = end + 1;
325 		if (!*end)
326 			++i;
327 	}
328 	if (!handle) {
329 		rte_errno = EINVAL;
330 		dlmsg = dlerror();
331 		if (dlmsg)
332 			DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
333 		goto glue_error;
334 	}
335 	sym = dlsym(handle, "mlx5_glue");
336 	if (!sym || !*sym) {
337 		rte_errno = EINVAL;
338 		dlmsg = dlerror();
339 		if (dlmsg)
340 			DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
341 		goto glue_error;
342 	}
343 	mlx5_glue = *sym;
344 	return 0;
345 
346 glue_error:
347 	if (handle)
348 		dlclose(handle);
349 	return -1;
350 }
351 
352 #endif
353 
354 /**
355  * Initialization routine for run-time dependency on rdma-core.
356  */
357 void
358 mlx5_glue_constructor(void)
359 {
360 	/*
361 	 * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
362 	 * huge pages. Calling ibv_fork_init() during init allows
363 	 * applications to use fork() safely for purposes other than
364 	 * using this PMD, which is not supported in forked processes.
365 	 */
366 	setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
367 	/* Match the size of Rx completion entry to the size of a cacheline. */
368 	if (RTE_CACHE_LINE_SIZE == 128)
369 		setenv("MLX5_CQE_SIZE", "128", 0);
370 	/*
371 	 * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
372 	 * cleanup all the Verbs resources even when the device was removed.
373 	 */
374 	setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
375 
376 #ifdef MLX5_GLUE
377 	if (mlx5_glue_dlopen() != 0)
378 		goto glue_error;
379 #endif
380 
381 #ifdef RTE_LIBRTE_MLX5_DEBUG
382 	/* Glue structure must not contain any NULL pointers. */
383 	{
384 		unsigned int i;
385 
386 		for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
387 			MLX5_ASSERT(((const void *const *)mlx5_glue)[i]);
388 	}
389 #endif
390 	if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
391 		rte_errno = EINVAL;
392 		DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
393 			"required", mlx5_glue->version, MLX5_GLUE_VERSION);
394 		goto glue_error;
395 	}
396 	mlx5_glue->fork_init();
397 	return;
398 
399 glue_error:
400 	DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
401 		" run-time dependency on rdma-core libraries (libibverbs,"
402 		" libmlx5)");
403 	mlx5_glue = NULL;
404 }
405 
406