xref: /dpdk/drivers/common/mlx5/linux/mlx5_common_os.c (revision 79aa430721b1e33706f71c84a6a718469b8f9053)
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 
12 #include <rte_errno.h>
13 
14 #include "mlx5_common.h"
15 #include "mlx5_common_utils.h"
16 #include "mlx5_glue.h"
17 
18 #ifdef MLX5_GLUE
19 const struct mlx5_glue *mlx5_glue;
20 #endif
21 
22 /**
23  * Get PCI information by sysfs device path.
24  *
25  * @param dev_path
26  *   Pointer to device sysfs folder name.
27  * @param[out] pci_addr
28  *   PCI bus address output buffer.
29  *
30  * @return
31  *   0 on success, a negative errno value otherwise and rte_errno is set.
32  */
33 int
34 mlx5_dev_to_pci_addr(const char *dev_path,
35 		     struct rte_pci_addr *pci_addr)
36 {
37 	FILE *file;
38 	char line[32];
39 	MKSTR(path, "%s/device/uevent", dev_path);
40 
41 	file = fopen(path, "rb");
42 	if (file == NULL) {
43 		rte_errno = errno;
44 		return -rte_errno;
45 	}
46 	while (fgets(line, sizeof(line), file) == line) {
47 		size_t len = strlen(line);
48 		int ret;
49 
50 		/* Truncate long lines. */
51 		if (len == (sizeof(line) - 1))
52 			while (line[(len - 1)] != '\n') {
53 				ret = fgetc(file);
54 				if (ret == EOF)
55 					break;
56 				line[(len - 1)] = ret;
57 			}
58 		/* Extract information. */
59 		if (sscanf(line,
60 			   "PCI_SLOT_NAME="
61 			   "%" SCNx32 ":%" SCNx8 ":%" SCNx8 ".%" SCNx8 "\n",
62 			   &pci_addr->domain,
63 			   &pci_addr->bus,
64 			   &pci_addr->devid,
65 			   &pci_addr->function) == 4) {
66 			ret = 0;
67 			break;
68 		}
69 	}
70 	fclose(file);
71 	return 0;
72 }
73 
74 /**
75  * Extract port name, as a number, from sysfs or netlink information.
76  *
77  * @param[in] port_name_in
78  *   String representing the port name.
79  * @param[out] port_info_out
80  *   Port information, including port name as a number and port name
81  *   type if recognized
82  *
83  * @return
84  *   port_name field set according to recognized name format.
85  */
86 void
87 mlx5_translate_port_name(const char *port_name_in,
88 			 struct mlx5_switch_info *port_info_out)
89 {
90 	char pf_c1, pf_c2, vf_c1, vf_c2;
91 	char *end;
92 	int sc_items;
93 
94 	/*
95 	 * Check for port-name as a string of the form pf0vf0
96 	 * (support kernel ver >= 5.0 or OFED ver >= 4.6).
97 	 */
98 	sc_items = sscanf(port_name_in, "%c%c%d%c%c%d",
99 			  &pf_c1, &pf_c2, &port_info_out->pf_num,
100 			  &vf_c1, &vf_c2, &port_info_out->port_name);
101 	if (sc_items == 6 &&
102 	    pf_c1 == 'p' && pf_c2 == 'f' &&
103 	    vf_c1 == 'v' && vf_c2 == 'f') {
104 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_PFVF;
105 		return;
106 	}
107 	/*
108 	 * Check for port-name as a string of the form p0
109 	 * (support kernel ver >= 5.0, or OFED ver >= 4.6).
110 	 */
111 	sc_items = sscanf(port_name_in, "%c%d",
112 			  &pf_c1, &port_info_out->port_name);
113 	if (sc_items == 2 && pf_c1 == 'p') {
114 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UPLINK;
115 		return;
116 	}
117 	/* Check for port-name as a number (support kernel ver < 5.0 */
118 	errno = 0;
119 	port_info_out->port_name = strtol(port_name_in, &end, 0);
120 	if (!errno &&
121 	    (size_t)(end - port_name_in) == strlen(port_name_in)) {
122 		port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_LEGACY;
123 		return;
124 	}
125 	port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UNKNOWN;
126 }
127 
128 #ifdef MLX5_GLUE
129 
130 /**
131  * Suffix RTE_EAL_PMD_PATH with "-glue".
132  *
133  * This function performs a sanity check on RTE_EAL_PMD_PATH before
134  * suffixing its last component.
135  *
136  * @param buf[out]
137  *   Output buffer, should be large enough otherwise NULL is returned.
138  * @param size
139  *   Size of @p out.
140  *
141  * @return
142  *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
143  */
144 static char *
145 mlx5_glue_path(char *buf, size_t size)
146 {
147 	static const char *const bad[] = { "/", ".", "..", NULL };
148 	const char *path = RTE_EAL_PMD_PATH;
149 	size_t len = strlen(path);
150 	size_t off;
151 	int i;
152 
153 	while (len && path[len - 1] == '/')
154 		--len;
155 	for (off = len; off && path[off - 1] != '/'; --off)
156 		;
157 	for (i = 0; bad[i]; ++i)
158 		if (!strncmp(path + off, bad[i], (int)(len - off)))
159 			goto error;
160 	i = snprintf(buf, size, "%.*s-glue", (int)len, path);
161 	if (i == -1 || (size_t)i >= size)
162 		goto error;
163 	return buf;
164 error:
165 	RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
166 		" RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
167 		" re-configure DPDK");
168 	return NULL;
169 }
170 
171 static int
172 mlx5_glue_dlopen(void)
173 {
174 	char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
175 	void *handle = NULL;
176 
177 	char const *path[] = {
178 		/*
179 		 * A basic security check is necessary before trusting
180 		 * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
181 		 */
182 		(geteuid() == getuid() && getegid() == getgid() ?
183 		 getenv("MLX5_GLUE_PATH") : NULL),
184 		/*
185 		 * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
186 		 * variant, otherwise let dlopen() look up libraries on its
187 		 * own.
188 		 */
189 		(*RTE_EAL_PMD_PATH ?
190 		 mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
191 	};
192 	unsigned int i = 0;
193 	void **sym;
194 	const char *dlmsg;
195 
196 	while (!handle && i != RTE_DIM(path)) {
197 		const char *end;
198 		size_t len;
199 		int ret;
200 
201 		if (!path[i]) {
202 			++i;
203 			continue;
204 		}
205 		end = strpbrk(path[i], ":;");
206 		if (!end)
207 			end = path[i] + strlen(path[i]);
208 		len = end - path[i];
209 		ret = 0;
210 		do {
211 			char name[ret + 1];
212 
213 			ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
214 				       (int)len, path[i],
215 				       (!len || *(end - 1) == '/') ? "" : "/");
216 			if (ret == -1)
217 				break;
218 			if (sizeof(name) != (size_t)ret + 1)
219 				continue;
220 			DRV_LOG(DEBUG, "Looking for rdma-core glue as "
221 				"\"%s\"", name);
222 			handle = dlopen(name, RTLD_LAZY);
223 			break;
224 		} while (1);
225 		path[i] = end + 1;
226 		if (!*end)
227 			++i;
228 	}
229 	if (!handle) {
230 		rte_errno = EINVAL;
231 		dlmsg = dlerror();
232 		if (dlmsg)
233 			DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
234 		goto glue_error;
235 	}
236 	sym = dlsym(handle, "mlx5_glue");
237 	if (!sym || !*sym) {
238 		rte_errno = EINVAL;
239 		dlmsg = dlerror();
240 		if (dlmsg)
241 			DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
242 		goto glue_error;
243 	}
244 	mlx5_glue = *sym;
245 	return 0;
246 
247 glue_error:
248 	if (handle)
249 		dlclose(handle);
250 	return -1;
251 }
252 
253 #endif
254 
255 /**
256  * Initialization routine for run-time dependency on rdma-core.
257  */
258 void
259 mlx5_glue_constructor(void)
260 {
261 	/*
262 	 * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
263 	 * huge pages. Calling ibv_fork_init() during init allows
264 	 * applications to use fork() safely for purposes other than
265 	 * using this PMD, which is not supported in forked processes.
266 	 */
267 	setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
268 	/* Match the size of Rx completion entry to the size of a cacheline. */
269 	if (RTE_CACHE_LINE_SIZE == 128)
270 		setenv("MLX5_CQE_SIZE", "128", 0);
271 	/*
272 	 * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
273 	 * cleanup all the Verbs resources even when the device was removed.
274 	 */
275 	setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
276 
277 #ifdef MLX5_GLUE
278 	if (mlx5_glue_dlopen() != 0)
279 		goto glue_error;
280 #endif
281 
282 #ifdef RTE_LIBRTE_MLX5_DEBUG
283 	/* Glue structure must not contain any NULL pointers. */
284 	{
285 		unsigned int i;
286 
287 		for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
288 			MLX5_ASSERT(((const void *const *)mlx5_glue)[i]);
289 	}
290 #endif
291 	if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
292 		rte_errno = EINVAL;
293 		DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
294 			"required", mlx5_glue->version, MLX5_GLUE_VERSION);
295 		goto glue_error;
296 	}
297 	mlx5_glue->fork_init();
298 	return;
299 
300 glue_error:
301 	DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
302 		" run-time dependency on rdma-core libraries (libibverbs,"
303 		" libmlx5)");
304 	mlx5_glue = NULL;
305 }
306