text: /*
   * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
   * Copyright (c) 2006 Cisco Systems, Inc.  All rights reserved.
   *
   * This software is available to you under a choice of one of two
   * licenses.  You may choose to be licensed under the terms of the GNU
   * General Public License (GPL) Version 2, available from the file
   * COPYING in the main directory of this source tree, or the
   * OpenIB.org BSD license below:
   *
   *     Redistribution and use in source and binary forms, with or
   *     without modification, are permitted provided that the following
   *     conditions are met:
   *
   *      - Redistributions of source code must retain the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer.
   *
   *      - Redistributions in binary form must reproduce the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer in the documentation and/or other materials
   *        provided with the distribution.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  #define _GNU_SOURCE
  #include <config.h>
  
  #include <stdlib.h>
  #include <string.h>
  #include <glob.h>
  #include <stdio.h>
  #include <dlfcn.h>
  #include <unistd.h>
  #include <sys/stat.h>
  #include <sys/types.h>
  #include <sys/time.h>
  #include <sys/resource.h>
  #include <dirent.h>
  #include <errno.h>
  #include <assert.h>
  
  #include "ibverbs.h"
  
  #pragma GCC diagnostic ignored "-Wmissing-prototypes"
  
  int abi_ver;
  
  struct ibv_sysfs_dev {
  	char		        sysfs_name[IBV_SYSFS_NAME_MAX];
  	char		        ibdev_name[IBV_SYSFS_NAME_MAX];
  	char		        sysfs_path[IBV_SYSFS_PATH_MAX];
  	char		        ibdev_path[IBV_SYSFS_PATH_MAX];
  	struct ibv_sysfs_dev   *next;
  	int			abi_ver;
  	int			have_driver;
  };
  
  struct ibv_driver_name {
  	char		       *name;
  	struct ibv_driver_name *next;
  };
  
  struct ibv_driver {
  	const char	       *name;
  	verbs_driver_init_func	verbs_init_func;
  	struct ibv_driver      *next;
  };
  
  static struct ibv_sysfs_dev *sysfs_dev_list;
  static struct ibv_driver_name *driver_name_list;
  static struct ibv_driver *head_driver, *tail_driver;
  
  static int find_sysfs_devs(void)
  {
  	char class_path[IBV_SYSFS_PATH_MAX];
  	struct ibv_sysfs_dev *sysfs_dev = NULL;
  	char value[8];
  	int ret = 0;
  	int i;
  
  	snprintf(class_path, sizeof class_path, "%s/class/infiniband_verbs",
  		 ibv_get_sysfs_path());
  
  	for (i = 0; i < 256; i++) {
  		if (!sysfs_dev)
  			sysfs_dev = malloc(sizeof *sysfs_dev);
  		if (!sysfs_dev) {
  			ret = ENOMEM;
  			goto out;
  		}
  
  		snprintf(sysfs_dev->sysfs_path, sizeof sysfs_dev->sysfs_path,
  			 "%s/uverbs%d", class_path, i);
  
  		snprintf(sysfs_dev->sysfs_name, sizeof sysfs_dev->sysfs_name,
  			"uverbs%d", i);
  
  		if (ibv_read_sysfs_file(sysfs_dev->sysfs_path, "ibdev",
  					sysfs_dev->ibdev_name,
  					sizeof sysfs_dev->ibdev_name) < 0)
  			continue;
  
  		snprintf(sysfs_dev->ibdev_path, sizeof sysfs_dev->ibdev_path,
  			 "%s/class/infiniband/%s", ibv_get_sysfs_path(),
  			 sysfs_dev->ibdev_name);
  
  		sysfs_dev->next        = sysfs_dev_list;
  		sysfs_dev->have_driver = 0;
  		if (ibv_read_sysfs_file(sysfs_dev->sysfs_path, "abi_version",
  					value, sizeof value) > 0)
  			sysfs_dev->abi_ver = strtol(value, NULL, 10);
  		else
  			sysfs_dev->abi_ver = 0;
  
  		sysfs_dev_list = sysfs_dev;
  		sysfs_dev      = NULL;
  	}
  
   out:
  	if (sysfs_dev)
  		free(sysfs_dev);
  
  	return ret;
  }
  
  void verbs_register_driver(const char *name,
  			   verbs_driver_init_func verbs_init_func)
  {
  	struct ibv_driver *driver;
  
  	driver = malloc(sizeof *driver);
  	if (!driver) {
  		fprintf(stderr, PFX "Warning: couldn't allocate driver for %s\n", name);
  		return;
  	}
  
  	driver->name            = name;
  	driver->verbs_init_func = verbs_init_func;
  	driver->next            = NULL;
  
  	if (tail_driver)
  		tail_driver->next = driver;
  	else
  		head_driver = driver;
  	tail_driver = driver;
  }
  
  static struct ibv_device *try_driver(struct ibv_driver *driver,
  				     struct ibv_sysfs_dev *sysfs_dev)
  {
  	struct verbs_device *vdev;
  	struct ibv_device *dev;
  	char value[16];
  
  	vdev = driver->verbs_init_func(sysfs_dev->sysfs_path, sysfs_dev->abi_ver);
  	if (!vdev)
  		return NULL;
  
  	dev = &vdev->device;
  	assert(dev->_ops._dummy1 == NULL);
  	assert(dev->_ops._dummy2 == NULL);
  
  	if (ibv_read_sysfs_file(sysfs_dev->ibdev_path, "node_type", value, sizeof value) < 0) {
  		fprintf(stderr, PFX "Warning: no node_type attr under %s.\n",
  			sysfs_dev->ibdev_path);
  			dev->node_type = IBV_NODE_UNKNOWN;
  	} else {
  		dev->node_type = strtol(value, NULL, 10);
  		if (dev->node_type < IBV_NODE_CA || dev->node_type > IBV_NODE_USNIC_UDP)
  			dev->node_type = IBV_NODE_UNKNOWN;
  	}
  
  	switch (dev->node_type) {
  	case IBV_NODE_CA:
  	case IBV_NODE_SWITCH:
  	case IBV_NODE_ROUTER:
  		dev->transport_type = IBV_TRANSPORT_IB;
  		break;
  	case IBV_NODE_RNIC:
  		dev->transport_type = IBV_TRANSPORT_IWARP;
  		break;
  	case IBV_NODE_USNIC:
  		dev->transport_type = IBV_TRANSPORT_USNIC;
  		break;
  	case IBV_NODE_USNIC_UDP:
  		dev->transport_type = IBV_TRANSPORT_USNIC_UDP;
  		break;
  	default:
  		dev->transport_type = IBV_TRANSPORT_UNKNOWN;
  		break;
  	}
  
  	strcpy(dev->dev_name,   sysfs_dev->sysfs_name);
  	strcpy(dev->dev_path,   sysfs_dev->sysfs_path);
  	strcpy(dev->name,       sysfs_dev->ibdev_name);
  	strcpy(dev->ibdev_path, sysfs_dev->ibdev_path);
  
  	return dev;
  }
  
  static struct ibv_device *try_drivers(struct ibv_sysfs_dev *sysfs_dev)
  {
  	struct ibv_driver *driver;
  	struct ibv_device *dev;
  
  	for (driver = head_driver; driver; driver = driver->next) {
  		dev = try_driver(driver, sysfs_dev);
  		if (dev)
  			return dev;
  	}
  
  	return NULL;
  }
  
  static int check_abi_version(const char *path)
  {
  	char value[8];
  
  	if (ibv_read_sysfs_file(path, "class/infiniband_verbs/abi_version",
  				value, sizeof value) < 0) {
  		return ENOSYS;
  	}
  
  	abi_ver = strtol(value, NULL, 10);
  
  	if (abi_ver < IB_USER_VERBS_MIN_ABI_VERSION ||
  	    abi_ver > IB_USER_VERBS_MAX_ABI_VERSION) {
  		fprintf(stderr, PFX "Fatal: kernel ABI version %d "
  			"doesn't match library version %d.\n",
  			abi_ver, IB_USER_VERBS_MAX_ABI_VERSION);
  		return ENOSYS;
  	}
  
  	return 0;
  }
  
  static void check_memlock_limit(void)
  {
  	struct rlimit rlim;
  
  	if (!geteuid())
  		return;
  
  	if (getrlimit(RLIMIT_MEMLOCK, &rlim)) {
  		fprintf(stderr, PFX "Warning: getrlimit(RLIMIT_MEMLOCK) failed.");
  		return;
  	}
  
  	if (rlim.rlim_cur <= 32768)
  		fprintf(stderr, PFX "Warning: RLIMIT_MEMLOCK is %lu bytes.\n"
  			"    This will severely limit memory registrations.\n",
  			rlim.rlim_cur);
  }
  
  static void add_device(struct ibv_device *dev,
  		       struct ibv_device ***dev_list,
  		       int *num_devices,
  		       int *list_size)
  {
  	struct ibv_device **new_list;
  
  	if (*list_size <= *num_devices) {
  		*list_size = *list_size ? *list_size * 2 : 1;
  		new_list = realloc(*dev_list, *list_size * sizeof (struct ibv_device *));
  		if (!new_list)
  			return;
  		*dev_list = new_list;
  	}
  
  	(*dev_list)[(*num_devices)++] = dev;
  }
  
  int ibverbs_init(struct ibv_device ***list)
  {
  	const char *sysfs_path;
  	struct ibv_sysfs_dev *sysfs_dev, *next_dev;
  	struct ibv_device *device;
  	int num_devices = 0;
  	int list_size = 0;
  	int statically_linked = 0;
  	int no_driver = 0;
  	int ret;
  
  	*list = NULL;
  
  	if (getenv("RDMAV_FORK_SAFE") || getenv("IBV_FORK_SAFE"))
  		if (ibv_fork_init())
  			fprintf(stderr, PFX "Warning: fork()-safety requested "
  				"but init failed\n");
  
  	sysfs_path = ibv_get_sysfs_path();
  	if (!sysfs_path)
  		return -ENOSYS;
  
  	ret = check_abi_version(sysfs_path);
  	if (ret)
  		return -ret;
  
  	check_memlock_limit();
  
  	ret = find_sysfs_devs();
  	if (ret)
  		return -ret;
  
  	for (sysfs_dev = sysfs_dev_list; sysfs_dev; sysfs_dev = sysfs_dev->next) {
  		device = try_drivers(sysfs_dev);
  		if (device) {
  			add_device(device, list, &num_devices, &list_size);
  			sysfs_dev->have_driver = 1;
  		} else
  			no_driver = 1;
  	}
  
  	if (!no_driver)
  		goto out;
  
  	/*
  	 * Check if we can dlopen() ourselves.  If this fails,
  	 * libibverbs is probably statically linked into the
  	 * executable, and we should just give up, since trying to
  	 * dlopen() a driver module will fail spectacularly (loading a
  	 * driver .so will bring in dynamic copies of libibverbs and
  	 * libdl to go along with the static copies the executable
  	 * has, which quickly leads to a crash.
  	 */
  	{
  		void *hand = dlopen(NULL, RTLD_NOW);
  		if (!hand) {
  			fprintf(stderr, PFX "Warning: dlopen(NULL) failed, "
  				"assuming static linking.\n");
  			statically_linked = 1;
  			goto out;
  		}
  		dlclose(hand);
  	}
  
  	for (sysfs_dev = sysfs_dev_list; sysfs_dev; sysfs_dev = sysfs_dev->next) {
  		if (sysfs_dev->have_driver)
  			continue;
  
  		device = try_drivers(sysfs_dev);
  		if (device) {
  			add_device(device, list, &num_devices, &list_size);
  			sysfs_dev->have_driver = 1;
  		}
  	}
  
  out:
  	for (sysfs_dev = sysfs_dev_list,
  		     next_dev = sysfs_dev ? sysfs_dev->next : NULL;
  	     sysfs_dev;
  	     sysfs_dev = next_dev, next_dev = sysfs_dev ? sysfs_dev->next : NULL) {
  		if (!sysfs_dev->have_driver && getenv("IBV_SHOW_WARNINGS")) {
  			fprintf(stderr, PFX "Warning: no userspace device-specific "
  				"driver found for %s\n", sysfs_dev->sysfs_path);
  			if (statically_linked)
  				fprintf(stderr, "	When linking libibverbs statically, "
  					"driver must be statically linked too.\n");
  		}
  		free(sysfs_dev);
  	}
  
  	return num_devices;
  }
  