1/*
2 * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
3 * Copyright (c) 2006 Cisco Systems, Inc.  All rights reserved.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses.  You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
10 *
11 *     Redistribution and use in source and binary forms, with or
12 *     without modification, are permitted provided that the following
13 *     conditions are met:
14 *
15 *      - Redistributions of source code must retain the above
16 *        copyright notice, this list of conditions and the following
17 *        disclaimer.
18 *
19 *      - Redistributions in binary form must reproduce the above
20 *        copyright notice, this list of conditions and the following
21 *        disclaimer in the documentation and/or other materials
22 *        provided with the distribution.
23 *
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31 * SOFTWARE.
32 */
33
34#if HAVE_CONFIG_H
35#  include <config.h>
36#endif /* HAVE_CONFIG_H */
37
38#include <stdlib.h>
39#include <string.h>
40#include <glob.h>
41#include <stdio.h>
42#include <dlfcn.h>
43#include <unistd.h>
44#include <sys/stat.h>
45#include <sys/types.h>
46#include <sys/time.h>
47#include <sys/resource.h>
48#include <dirent.h>
49#include <errno.h>
50
51#include "ibverbs.h"
52
53HIDDEN int abi_ver;
54
55struct ibv_sysfs_dev {
56	char		        sysfs_name[IBV_SYSFS_NAME_MAX];
57	char		        ibdev_name[IBV_SYSFS_NAME_MAX];
58	char		        sysfs_path[IBV_SYSFS_PATH_MAX];
59	char		        ibdev_path[IBV_SYSFS_PATH_MAX];
60	struct ibv_sysfs_dev   *next;
61	int			abi_ver;
62	int			have_driver;
63};
64
65struct ibv_driver_name {
66	char		       *name;
67	struct ibv_driver_name *next;
68};
69
70struct ibv_driver {
71	const char	       *name;
72	ibv_driver_init_func	init_func;
73	struct ibv_driver      *next;
74};
75
76static struct ibv_sysfs_dev *sysfs_dev_list;
77static struct ibv_driver_name *driver_name_list;
78static struct ibv_driver *head_driver, *tail_driver;
79
80static int find_sysfs_devs(void)
81{
82#ifdef __linux__
83	char class_path[IBV_SYSFS_PATH_MAX];
84	DIR *class_dir;
85	struct dirent *dent;
86	struct ibv_sysfs_dev *sysfs_dev = NULL;
87	char value[8];
88	int ret = 0;
89
90	snprintf(class_path, sizeof class_path, "%s/class/infiniband_verbs",
91		 ibv_get_sysfs_path());
92
93	class_dir = opendir(class_path);
94	if (!class_dir)
95		return ENOSYS;
96
97	while ((dent = readdir(class_dir))) {
98		struct stat buf;
99
100		if (dent->d_name[0] == '.')
101			continue;
102
103		if (!sysfs_dev)
104			sysfs_dev = malloc(sizeof *sysfs_dev);
105		if (!sysfs_dev) {
106			ret = ENOMEM;
107			goto out;
108		}
109
110		snprintf(sysfs_dev->sysfs_path, sizeof sysfs_dev->sysfs_path,
111			 "%s/%s", class_path, dent->d_name);
112
113		if (stat(sysfs_dev->sysfs_path, &buf)) {
114			fprintf(stderr, PFX "Warning: couldn't stat '%s'.\n",
115				sysfs_dev->sysfs_path);
116			continue;
117		}
118
119		if (!S_ISDIR(buf.st_mode))
120			continue;
121
122		snprintf(sysfs_dev->sysfs_name, sizeof sysfs_dev->sysfs_name,
123			"%s", dent->d_name);
124
125		if (ibv_read_sysfs_file(sysfs_dev->sysfs_path, "ibdev",
126					sysfs_dev->ibdev_name,
127					sizeof sysfs_dev->ibdev_name) < 0) {
128			fprintf(stderr, PFX "Warning: no ibdev class attr for '%s'.\n",
129				dent->d_name);
130			continue;
131		}
132
133		snprintf(sysfs_dev->ibdev_path, sizeof sysfs_dev->ibdev_path,
134			 "%s/class/infiniband/%s", ibv_get_sysfs_path(),
135			 sysfs_dev->ibdev_name);
136
137		sysfs_dev->next        = sysfs_dev_list;
138		sysfs_dev->have_driver = 0;
139		if (ibv_read_sysfs_file(sysfs_dev->sysfs_path, "abi_version",
140					value, sizeof value) > 0)
141			sysfs_dev->abi_ver = strtol(value, NULL, 10);
142		else
143			sysfs_dev->abi_ver = 0;
144
145		sysfs_dev_list = sysfs_dev;
146		sysfs_dev      = NULL;
147	}
148
149 out:
150	if (sysfs_dev)
151		free(sysfs_dev);
152
153	closedir(class_dir);
154	return ret;
155#else
156	char class_path[IBV_SYSFS_PATH_MAX];
157	struct ibv_sysfs_dev *sysfs_dev = NULL;
158	char value[8];
159	int ret = 0;
160	int i;
161
162	snprintf(class_path, sizeof class_path, "%s/class/infiniband_verbs",
163		 ibv_get_sysfs_path());
164
165	for (i = 0; i < 256; i++) {
166		if (!sysfs_dev)
167			sysfs_dev = malloc(sizeof *sysfs_dev);
168		if (!sysfs_dev) {
169			ret = ENOMEM;
170			goto out;
171		}
172
173		snprintf(sysfs_dev->sysfs_path, sizeof sysfs_dev->sysfs_path,
174			 "%s/uverbs%d", class_path, i);
175
176		snprintf(sysfs_dev->sysfs_name, sizeof sysfs_dev->sysfs_name,
177			"uverbs%d", i);
178
179		if (ibv_read_sysfs_file(sysfs_dev->sysfs_path, "ibdev",
180					sysfs_dev->ibdev_name,
181					sizeof sysfs_dev->ibdev_name) < 0)
182			continue;
183
184		snprintf(sysfs_dev->ibdev_path, sizeof sysfs_dev->ibdev_path,
185			 "%s/class/infiniband/%s", ibv_get_sysfs_path(),
186			 sysfs_dev->ibdev_name);
187
188		sysfs_dev->next        = sysfs_dev_list;
189		sysfs_dev->have_driver = 0;
190		if (ibv_read_sysfs_file(sysfs_dev->sysfs_path, "abi_version",
191					value, sizeof value) > 0)
192			sysfs_dev->abi_ver = strtol(value, NULL, 10);
193		else
194			sysfs_dev->abi_ver = 0;
195
196		sysfs_dev_list = sysfs_dev;
197		sysfs_dev      = NULL;
198	}
199
200 out:
201	if (sysfs_dev)
202		free(sysfs_dev);
203
204	return ret;
205
206#endif
207}
208
209void ibv_register_driver(const char *name, ibv_driver_init_func init_func)
210{
211	struct ibv_driver *driver;
212
213	driver = malloc(sizeof *driver);
214	if (!driver) {
215		fprintf(stderr, PFX "Warning: couldn't allocate driver for %s\n", name);
216		return;
217	}
218
219	driver->name      = name;
220	driver->init_func = init_func;
221	driver->next      = NULL;
222
223	if (tail_driver)
224		tail_driver->next = driver;
225	else
226		head_driver = driver;
227	tail_driver = driver;
228}
229
230static void load_driver(const char *name)
231{
232	char *so_name;
233	void *dlhandle;
234
235#define __IBV_QUOTE(x)	#x
236#define IBV_QUOTE(x)	__IBV_QUOTE(x)
237
238	if (asprintf(&so_name,
239		     name[0] == '/' ?
240		     "%s-" IBV_QUOTE(IBV_DEVICE_LIBRARY_EXTENSION) ".so" :
241		     "lib%s-" IBV_QUOTE(IBV_DEVICE_LIBRARY_EXTENSION) ".so",
242		     name) < 0) {
243		fprintf(stderr, PFX "Warning: couldn't load driver '%s'.\n",
244			name);
245		return;
246	}
247
248	dlhandle = dlopen(so_name, RTLD_NOW);
249	if (!dlhandle) {
250		fprintf(stderr, PFX "Warning: couldn't load driver '%s': %s\n",
251			name, dlerror());
252		goto out;
253	}
254
255out:
256	free(so_name);
257}
258
259static void load_drivers(void)
260{
261	struct ibv_driver_name *name, *next_name;
262	const char *env;
263	char *list, *env_name;
264
265	/*
266	 * Only use drivers passed in through the calling user's
267	 * environment if we're not running setuid.
268	 */
269	if (getuid() == geteuid()) {
270		if ((env = getenv("RDMAV_DRIVERS"))) {
271			list = strdupa(env);
272			while ((env_name = strsep(&list, ":;")))
273				load_driver(env_name);
274		} else if ((env = getenv("IBV_DRIVERS"))) {
275			list = strdupa(env);
276			while ((env_name = strsep(&list, ":;")))
277				load_driver(env_name);
278		}
279	}
280
281	for (name = driver_name_list, next_name = name ? name->next : NULL;
282	     name;
283	     name = next_name, next_name = name ? name->next : NULL) {
284		load_driver(name->name);
285		free(name->name);
286		free(name);
287	}
288}
289
290static void read_config_file(const char *path)
291{
292	FILE *conf;
293	char *line = NULL;
294	char *config;
295	char *field;
296	size_t buflen = 0;
297	ssize_t len;
298
299	conf = fopen(path, "r");
300	if (!conf) {
301		fprintf(stderr, PFX "Warning: couldn't read config file %s.\n",
302			path);
303		return;
304	}
305
306	while ((len = getline(&line, &buflen, conf)) != -1) {
307		config = line + strspn(line, "\t ");
308		if (config[0] == '\n' || config[0] == '#')
309			continue;
310
311		field = strsep(&config, "\n\t ");
312
313		if (strcmp(field, "driver") == 0) {
314			struct ibv_driver_name *driver_name;
315
316			config += strspn(config, "\t ");
317			field = strsep(&config, "\n\t ");
318
319			driver_name = malloc(sizeof *driver_name);
320			if (!driver_name) {
321				fprintf(stderr, PFX "Warning: couldn't allocate "
322					"driver name '%s'.\n", field);
323				continue;
324			}
325
326			driver_name->name = strdup(field);
327			if (!driver_name->name) {
328				fprintf(stderr, PFX "Warning: couldn't allocate "
329					"driver name '%s'.\n", field);
330				free(driver_name);
331				continue;
332			}
333
334			driver_name->next = driver_name_list;
335			driver_name_list  = driver_name;
336		} else
337			fprintf(stderr, PFX "Warning: ignoring bad config directive "
338				"'%s' in file '%s'.\n", field, path);
339	}
340
341	if (line)
342		free(line);
343	fclose(conf);
344}
345
346static void read_config(void)
347{
348	DIR *conf_dir;
349	struct dirent *dent;
350	char *path;
351
352	conf_dir = opendir(IBV_CONFIG_DIR);
353	if (!conf_dir) {
354		fprintf(stderr, PFX "Warning: couldn't open config directory '%s'.\n",
355			IBV_CONFIG_DIR);
356		return;
357	}
358
359	while ((dent = readdir(conf_dir))) {
360		struct stat buf;
361
362		if (asprintf(&path, "%s/%s", IBV_CONFIG_DIR, dent->d_name) < 0) {
363			fprintf(stderr, PFX "Warning: couldn't read config file %s/%s.\n",
364				IBV_CONFIG_DIR, dent->d_name);
365			return;
366		}
367
368		if (stat(path, &buf)) {
369			fprintf(stderr, PFX "Warning: couldn't stat config file '%s'.\n",
370				path);
371			goto next;
372		}
373
374		if (!S_ISREG(buf.st_mode))
375			goto next;
376
377		read_config_file(path);
378next:
379		free(path);
380	}
381
382	closedir(conf_dir);
383}
384
385static struct ibv_device *try_driver(struct ibv_driver *driver,
386				     struct ibv_sysfs_dev *sysfs_dev)
387{
388	struct ibv_device *dev;
389	char value[8];
390
391	dev = driver->init_func(sysfs_dev->sysfs_path, sysfs_dev->abi_ver);
392	if (!dev)
393		return NULL;
394
395	if (ibv_read_sysfs_file(sysfs_dev->ibdev_path, "node_type", value, sizeof value) < 0) {
396		fprintf(stderr, PFX "Warning: no node_type attr under %s.\n",
397			sysfs_dev->ibdev_path);
398			dev->node_type = IBV_NODE_UNKNOWN;
399	} else {
400		dev->node_type = strtol(value, NULL, 10);
401		if (dev->node_type < IBV_NODE_CA || dev->node_type > IBV_NODE_RNIC)
402			dev->node_type = IBV_NODE_UNKNOWN;
403	}
404out:
405
406	switch (dev->node_type) {
407	case IBV_NODE_CA:
408	case IBV_NODE_SWITCH:
409	case IBV_NODE_ROUTER:
410		dev->transport_type = IBV_TRANSPORT_IB;
411		break;
412	case IBV_NODE_RNIC:
413		dev->transport_type = IBV_TRANSPORT_IWARP;
414		break;
415	default:
416		dev->transport_type = IBV_TRANSPORT_UNKNOWN;
417		break;
418	}
419
420	strcpy(dev->dev_name,   sysfs_dev->sysfs_name);
421	strcpy(dev->dev_path,   sysfs_dev->sysfs_path);
422	strcpy(dev->name,       sysfs_dev->ibdev_name);
423	strcpy(dev->ibdev_path, sysfs_dev->ibdev_path);
424
425	return dev;
426}
427
428static struct ibv_device *try_drivers(struct ibv_sysfs_dev *sysfs_dev)
429{
430	struct ibv_driver *driver;
431	struct ibv_device *dev;
432
433	for (driver = head_driver; driver; driver = driver->next) {
434		dev = try_driver(driver, sysfs_dev);
435		if (dev)
436			return dev;
437	}
438
439	return NULL;
440}
441
442static int check_abi_version(const char *path)
443{
444	char value[8];
445
446	if (ibv_read_sysfs_file(path, "class/infiniband_verbs/abi_version",
447				value, sizeof value) < 0) {
448		return ENOSYS;
449	}
450
451	abi_ver = strtol(value, NULL, 10);
452
453	if (abi_ver < IB_USER_VERBS_MIN_ABI_VERSION ||
454	    abi_ver > IB_USER_VERBS_MAX_ABI_VERSION) {
455		fprintf(stderr, PFX "Fatal: kernel ABI version %d "
456			"doesn't match library version %d.\n",
457			abi_ver, IB_USER_VERBS_MAX_ABI_VERSION);
458		return ENOSYS;
459	}
460
461	return 0;
462}
463
464static void check_memlock_limit(void)
465{
466	struct rlimit rlim;
467
468	if (!geteuid())
469		return;
470
471	if (getrlimit(RLIMIT_MEMLOCK, &rlim)) {
472		fprintf(stderr, PFX "Warning: getrlimit(RLIMIT_MEMLOCK) failed.");
473		return;
474	}
475
476	if (rlim.rlim_cur <= 32768)
477		fprintf(stderr, PFX "Warning: RLIMIT_MEMLOCK is %lu bytes.\n"
478			"    This will severely limit memory registrations.\n",
479			rlim.rlim_cur);
480}
481
482static void add_device(struct ibv_device *dev,
483		       struct ibv_device ***dev_list,
484		       int *num_devices,
485		       int *list_size)
486{
487	struct ibv_device **new_list;
488
489	if (*list_size <= *num_devices) {
490		*list_size = *list_size ? *list_size * 2 : 1;
491		new_list = realloc(*dev_list, *list_size * sizeof (struct ibv_device *));
492		if (!new_list)
493			return;
494		*dev_list = new_list;
495	}
496
497	(*dev_list)[(*num_devices)++] = dev;
498}
499
500HIDDEN int ibverbs_init(struct ibv_device ***list)
501{
502	const char *sysfs_path;
503	struct ibv_sysfs_dev *sysfs_dev, *next_dev;
504	struct ibv_device *device;
505	int num_devices = 0;
506	int list_size = 0;
507	int statically_linked = 0;
508	int no_driver = 0;
509	int ret;
510
511	*list = NULL;
512
513	if (getenv("RDMAV_FORK_SAFE") || getenv("IBV_FORK_SAFE"))
514		if (ibv_fork_init())
515			fprintf(stderr, PFX "Warning: fork()-safety requested "
516				"but init failed\n");
517
518	sysfs_path = ibv_get_sysfs_path();
519	if (!sysfs_path)
520		return -ENOSYS;
521
522	ret = check_abi_version(sysfs_path);
523	if (ret)
524		return -ret;
525
526	check_memlock_limit();
527
528	read_config();
529
530	ret = find_sysfs_devs();
531	if (ret)
532		return -ret;
533
534	for (sysfs_dev = sysfs_dev_list; sysfs_dev; sysfs_dev = sysfs_dev->next) {
535		device = try_drivers(sysfs_dev);
536		if (device) {
537			add_device(device, list, &num_devices, &list_size);
538			sysfs_dev->have_driver = 1;
539		} else
540			no_driver = 1;
541	}
542
543	if (!no_driver)
544		goto out;
545
546	/*
547	 * Check if we can dlopen() ourselves.  If this fails,
548	 * libibverbs is probably statically linked into the
549	 * executable, and we should just give up, since trying to
550	 * dlopen() a driver module will fail spectacularly (loading a
551	 * driver .so will bring in dynamic copies of libibverbs and
552	 * libdl to go along with the static copies the executable
553	 * has, which quickly leads to a crash.
554	 */
555	{
556		void *hand = dlopen(NULL, RTLD_NOW);
557		if (!hand) {
558			fprintf(stderr, PFX "Warning: dlopen(NULL) failed, "
559				"assuming static linking.\n");
560			statically_linked = 1;
561			goto out;
562		}
563		dlclose(hand);
564	}
565
566	load_drivers();
567
568	for (sysfs_dev = sysfs_dev_list; sysfs_dev; sysfs_dev = sysfs_dev->next) {
569		if (sysfs_dev->have_driver)
570			continue;
571
572		device = try_drivers(sysfs_dev);
573		if (device) {
574			add_device(device, list, &num_devices, &list_size);
575			sysfs_dev->have_driver = 1;
576		}
577	}
578
579out:
580	for (sysfs_dev = sysfs_dev_list,
581		     next_dev = sysfs_dev ? sysfs_dev->next : NULL;
582	     sysfs_dev;
583	     sysfs_dev = next_dev, next_dev = sysfs_dev ? sysfs_dev->next : NULL) {
584		if (!sysfs_dev->have_driver) {
585			fprintf(stderr, PFX "Warning: no userspace device-specific "
586				"driver found for %s\n", sysfs_dev->sysfs_path);
587			if (statically_linked)
588				fprintf(stderr, "	When linking libibverbs statically, "
589					"driver must be statically linked too.\n");
590		}
591		free(sysfs_dev);
592	}
593
594	return num_devices;
595}
596