remove experimental tags from all symbol definitions
[dpdk.git] / lib / librte_eal / common / eal_common_dev.c
index 1194419..86f801d 100644 (file)
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   Copyright(c) 2014 6WIND S.A.
- *   All rights reserved.
- *
- *   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.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2010-2014 Intel Corporation.
+ * Copyright(c) 2014 6WIND S.A.
  */
 
+#include <stdio.h>
 #include <string.h>
 #include <inttypes.h>
 #include <sys/queue.h>
 
+#include <rte_compat.h>
+#include <rte_bus.h>
+#include <rte_class.h>
 #include <rte_dev.h>
 #include <rte_devargs.h>
 #include <rte_debug.h>
-#include <rte_devargs.h>
+#include <rte_errno.h>
+#include <rte_kvargs.h>
+#include <rte_log.h>
+#include <rte_spinlock.h>
+#include <rte_malloc.h>
+#include <rte_string_fns.h>
 
 #include "eal_private.h"
+#include "hotplug_mp.h"
 
-/** Global list of device drivers. */
-static struct rte_driver_list dev_driver_list =
-       TAILQ_HEAD_INITIALIZER(dev_driver_list);
+/**
+ * The device event callback description.
+ *
+ * It contains callback address to be registered by user application,
+ * the pointer to the parameters for callback, and the device name.
+ */
+struct dev_event_callback {
+       TAILQ_ENTRY(dev_event_callback) next; /**< Callbacks list */
+       rte_dev_event_cb_fn cb_fn;            /**< Callback address */
+       void *cb_arg;                         /**< Callback parameter */
+       char *dev_name;  /**< Callback device name, NULL is for all device */
+       uint32_t active;                      /**< Callback is executing */
+};
 
-/* register a driver */
-void
-rte_eal_driver_register(struct rte_driver *driver)
+/** @internal Structure to keep track of registered callbacks */
+TAILQ_HEAD(dev_event_cb_list, dev_event_callback);
+
+/* The device event callback list for all registered callbacks. */
+static struct dev_event_cb_list dev_event_cbs;
+
+/* spinlock for device callbacks */
+static rte_spinlock_t dev_event_lock = RTE_SPINLOCK_INITIALIZER;
+
+struct dev_next_ctx {
+       struct rte_dev_iterator *it;
+       const char *bus_str;
+       const char *cls_str;
+};
+
+#define CTX(it, bus_str, cls_str) \
+       (&(const struct dev_next_ctx){ \
+               .it = it, \
+               .bus_str = bus_str, \
+               .cls_str = cls_str, \
+       })
+
+#define ITCTX(ptr) \
+       (((struct dev_next_ctx *)(intptr_t)ptr)->it)
+
+#define BUSCTX(ptr) \
+       (((struct dev_next_ctx *)(intptr_t)ptr)->bus_str)
+
+#define CLSCTX(ptr) \
+       (((struct dev_next_ctx *)(intptr_t)ptr)->cls_str)
+
+static int cmp_dev_name(const struct rte_device *dev, const void *_name)
 {
-       TAILQ_INSERT_TAIL(&dev_driver_list, driver, next);
+       const char *name = _name;
+
+       return strcmp(dev->name, name);
 }
 
-/* unregister a driver */
-void
-rte_eal_driver_unregister(struct rte_driver *driver)
+int
+rte_dev_is_probed(const struct rte_device *dev)
+{
+       /* The field driver should be set only when the probe is successful. */
+       return dev->driver != NULL;
+}
+
+/* helper function to build devargs, caller should free the memory */
+static int
+build_devargs(const char *busname, const char *devname,
+             const char *drvargs, char **devargs)
+{
+       int length;
+
+       length = snprintf(NULL, 0, "%s:%s,%s", busname, devname, drvargs);
+       if (length < 0)
+               return -EINVAL;
+
+       *devargs = malloc(length + 1);
+       if (*devargs == NULL)
+               return -ENOMEM;
+
+       length = snprintf(*devargs, length + 1, "%s:%s,%s",
+                       busname, devname, drvargs);
+       if (length < 0) {
+               free(*devargs);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+int
+rte_eal_hotplug_add(const char *busname, const char *devname,
+                   const char *drvargs)
 {
-       TAILQ_REMOVE(&dev_driver_list, driver, next);
+
+       char *devargs;
+       int ret;
+
+       ret = build_devargs(busname, devname, drvargs, &devargs);
+       if (ret != 0)
+               return ret;
+
+       ret = rte_dev_probe(devargs);
+       free(devargs);
+
+       return ret;
 }
 
+/* probe device at local process. */
 int
-rte_eal_dev_init(uint8_t init_pri)
+local_dev_probe(const char *devargs, struct rte_device **new_dev)
 {
-       struct rte_devargs *devargs;
-       struct rte_driver *driver;
+       struct rte_device *dev;
+       struct rte_devargs *da;
+       int ret;
+
+       *new_dev = NULL;
+       da = calloc(1, sizeof(*da));
+       if (da == NULL)
+               return -ENOMEM;
+
+       ret = rte_devargs_parse(da, devargs);
+       if (ret)
+               goto err_devarg;
+
+       if (da->bus->plug == NULL) {
+               RTE_LOG(ERR, EAL, "Function plug not supported by bus (%s)\n",
+                       da->bus->name);
+               ret = -ENOTSUP;
+               goto err_devarg;
+       }
+
+       ret = rte_devargs_insert(&da);
+       if (ret)
+               goto err_devarg;
 
-       /*
-        * Note that the dev_driver_list is populated here
-        * from calls made to rte_eal_driver_register from constructor functions
-        * embedded into PMD modules via the PMD_REGISTER_DRIVER macro
+       /* the rte_devargs will be referenced in the matching rte_device */
+       ret = da->bus->scan();
+       if (ret)
+               goto err_devarg;
+
+       dev = da->bus->find_device(NULL, cmp_dev_name, da->name);
+       if (dev == NULL) {
+               RTE_LOG(ERR, EAL, "Cannot find device (%s)\n",
+                       da->name);
+               ret = -ENODEV;
+               goto err_devarg;
+       }
+       /* Since there is a matching device, it is now its responsibility
+        * to manage the devargs we've just inserted. From this point
+        * those devargs shouldn't be removed manually anymore.
         */
 
-       /* call the init function for each virtual device */
-       TAILQ_FOREACH(devargs, &devargs_list, next) {
+       ret = dev->bus->plug(dev);
+       if (ret && !rte_dev_is_probed(dev)) { /* if hasn't ever succeeded */
+               RTE_LOG(ERR, EAL, "Driver cannot attach the device (%s)\n",
+                       dev->name);
+               return ret;
+       }
 
-               if (devargs->type != RTE_DEVTYPE_VIRTUAL)
-                       continue;
+       *new_dev = dev;
+       return ret;
+
+err_devarg:
+       if (rte_devargs_remove(da) != 0) {
+               free(da->args);
+               free(da);
+       }
+       return ret;
+}
+
+int
+rte_dev_probe(const char *devargs)
+{
+       struct eal_dev_mp_req req;
+       struct rte_device *dev;
+       int ret;
+
+       memset(&req, 0, sizeof(req));
+       req.t = EAL_DEV_REQ_TYPE_ATTACH;
+       strlcpy(req.devargs, devargs, EAL_DEV_MP_DEV_ARGS_MAX_LEN);
+
+       if (rte_eal_process_type() != RTE_PROC_PRIMARY) {
+               /**
+                * If in secondary process, just send IPC request to
+                * primary process.
+                */
+               ret = eal_dev_hotplug_request_to_primary(&req);
+               if (ret != 0) {
+                       RTE_LOG(ERR, EAL,
+                               "Failed to send hotplug request to primary\n");
+                       return -ENOMSG;
+               }
+               if (req.result != 0)
+                       RTE_LOG(ERR, EAL,
+                               "Failed to hotplug add device\n");
+               return req.result;
+       }
+
+       /* attach a shared device from primary start from here: */
+
+       /* primary attach the new device itself. */
+       ret = local_dev_probe(devargs, &dev);
+
+       if (ret != 0) {
+               RTE_LOG(ERR, EAL,
+                       "Failed to attach device on primary process\n");
+
+               /**
+                * it is possible that secondary process failed to attached a
+                * device that primary process have during initialization,
+                * so for -EEXIST case, we still need to sync with secondary
+                * process.
+                */
+               if (ret != -EEXIST)
+                       return ret;
+       }
+
+       /* primary send attach sync request to secondary. */
+       ret = eal_dev_hotplug_request_to_secondary(&req);
+
+       /* if any communication error, we need to rollback. */
+       if (ret != 0) {
+               RTE_LOG(ERR, EAL,
+                       "Failed to send hotplug add request to secondary\n");
+               ret = -ENOMSG;
+               goto rollback;
+       }
+
+       /**
+        * if any secondary failed to attach, we need to consider if rollback
+        * is necessary.
+        */
+       if (req.result != 0) {
+               RTE_LOG(ERR, EAL,
+                       "Failed to attach device on secondary process\n");
+               ret = req.result;
+
+               /* for -EEXIST, we don't need to rollback. */
+               if (ret == -EEXIST)
+                       return ret;
+               goto rollback;
+       }
+
+       return 0;
+
+rollback:
+       req.t = EAL_DEV_REQ_TYPE_ATTACH_ROLLBACK;
+
+       /* primary send rollback request to secondary. */
+       if (eal_dev_hotplug_request_to_secondary(&req) != 0)
+               RTE_LOG(WARNING, EAL,
+                       "Failed to rollback device attach on secondary."
+                       "Devices in secondary may not sync with primary\n");
+
+       /* primary rollback itself. */
+       if (local_dev_remove(dev) != 0)
+               RTE_LOG(WARNING, EAL,
+                       "Failed to rollback device attach on primary."
+                       "Devices in secondary may not sync with primary\n");
+
+       return ret;
+}
+
+int
+rte_eal_hotplug_remove(const char *busname, const char *devname)
+{
+       struct rte_device *dev;
+       struct rte_bus *bus;
+
+       bus = rte_bus_find_by_name(busname);
+       if (bus == NULL) {
+               RTE_LOG(ERR, EAL, "Cannot find bus (%s)\n", busname);
+               return -ENOENT;
+       }
+
+       dev = bus->find_device(NULL, cmp_dev_name, devname);
+       if (dev == NULL) {
+               RTE_LOG(ERR, EAL, "Cannot find plugged device (%s)\n", devname);
+               return -EINVAL;
+       }
+
+       return rte_dev_remove(dev);
+}
+
+/* remove device at local process. */
+int
+local_dev_remove(struct rte_device *dev)
+{
+       int ret;
+
+       if (dev->bus->unplug == NULL) {
+               RTE_LOG(ERR, EAL, "Function unplug not supported by bus (%s)\n",
+                       dev->bus->name);
+               return -ENOTSUP;
+       }
+
+       ret = dev->bus->unplug(dev);
+       if (ret) {
+               RTE_LOG(ERR, EAL, "Driver cannot detach the device (%s)\n",
+                       dev->name);
+               return ret;
+       }
+
+       return 0;
+}
+
+int
+rte_dev_remove(struct rte_device *dev)
+{
+       struct eal_dev_mp_req req;
+       char *devargs;
+       int ret;
+
+       if (!rte_dev_is_probed(dev)) {
+               RTE_LOG(ERR, EAL, "Device is not probed\n");
+               return -ENOENT;
+       }
+
+       ret = build_devargs(dev->bus->name, dev->name, "", &devargs);
+       if (ret != 0)
+               return ret;
+
+       memset(&req, 0, sizeof(req));
+       req.t = EAL_DEV_REQ_TYPE_DETACH;
+       strlcpy(req.devargs, devargs, EAL_DEV_MP_DEV_ARGS_MAX_LEN);
+       free(devargs);
+
+       if (rte_eal_process_type() != RTE_PROC_PRIMARY) {
+               /**
+                * If in secondary process, just send IPC request to
+                * primary process.
+                */
+               ret = eal_dev_hotplug_request_to_primary(&req);
+               if (ret != 0) {
+                       RTE_LOG(ERR, EAL,
+                               "Failed to send hotplug request to primary\n");
+                       return -ENOMSG;
+               }
+               if (req.result != 0)
+                       RTE_LOG(ERR, EAL,
+                               "Failed to hotplug remove device\n");
+               return req.result;
+       }
+
+       /* detach a device from primary start from here: */
 
-               TAILQ_FOREACH(driver, &dev_driver_list, next) {
-                       /* RTE_DEVTYPE_VIRTUAL can only be a virtual or bonded device,
-                        * virtual devices are initialized pre PCI probing and bonded
-                        * device are post pci probing */
-                       if ((driver->type == PMD_VDEV && init_pri ==
-                                       PMD_INIT_PRE_PCI_PROBE) ||
-                               (driver->type == PMD_BDEV && init_pri ==
-                                               PMD_INIT_POST_PCI_PROBE)) {
-
-                               /* search a driver prefix in virtual device name */
-                               if (!strncmp(driver->name, devargs->virtual.drv_name,
-                                               strlen(driver->name))) {
-                                       printf("init (%u) %s\n", init_pri, devargs->virtual.drv_name);
-                                       driver->init(devargs->virtual.drv_name,
-                                               devargs->args);
-                                       break;
+       /* primary send detach sync request to secondary */
+       ret = eal_dev_hotplug_request_to_secondary(&req);
+
+       /**
+        * if communication error, we need to rollback, because it is possible
+        * part of the secondary processes still detached it successfully.
+        */
+       if (ret != 0) {
+               RTE_LOG(ERR, EAL,
+                       "Failed to send device detach request to secondary\n");
+               ret = -ENOMSG;
+               goto rollback;
+       }
+
+       /**
+        * if any secondary failed to detach, we need to consider if rollback
+        * is necessary.
+        */
+       if (req.result != 0) {
+               RTE_LOG(ERR, EAL,
+                       "Failed to detach device on secondary process\n");
+               ret = req.result;
+               /**
+                * if -ENOENT, we don't need to rollback, since devices is
+                * already detached on secondary process.
+                */
+               if (ret != -ENOENT)
+                       goto rollback;
+       }
+
+       /* primary detach the device itself. */
+       ret = local_dev_remove(dev);
+
+       /* if primary failed, still need to consider if rollback is necessary */
+       if (ret != 0) {
+               RTE_LOG(ERR, EAL,
+                       "Failed to detach device on primary process\n");
+               /* if -ENOENT, we don't need to rollback */
+               if (ret == -ENOENT)
+                       return ret;
+               goto rollback;
+       }
+
+       return 0;
+
+rollback:
+       req.t = EAL_DEV_REQ_TYPE_DETACH_ROLLBACK;
+
+       /* primary send rollback request to secondary. */
+       if (eal_dev_hotplug_request_to_secondary(&req) != 0)
+               RTE_LOG(WARNING, EAL,
+                       "Failed to rollback device detach on secondary."
+                       "Devices in secondary may not sync with primary\n");
+
+       return ret;
+}
+
+int
+rte_dev_event_callback_register(const char *device_name,
+                               rte_dev_event_cb_fn cb_fn,
+                               void *cb_arg)
+{
+       struct dev_event_callback *event_cb;
+       int ret;
+
+       if (!cb_fn)
+               return -EINVAL;
+
+       rte_spinlock_lock(&dev_event_lock);
+
+       if (TAILQ_EMPTY(&dev_event_cbs))
+               TAILQ_INIT(&dev_event_cbs);
+
+       TAILQ_FOREACH(event_cb, &dev_event_cbs, next) {
+               if (event_cb->cb_fn == cb_fn && event_cb->cb_arg == cb_arg) {
+                       if (device_name == NULL && event_cb->dev_name == NULL)
+                               break;
+                       if (device_name == NULL || event_cb->dev_name == NULL)
+                               continue;
+                       if (!strcmp(event_cb->dev_name, device_name))
+                               break;
+               }
+       }
+
+       /* create a new callback. */
+       if (event_cb == NULL) {
+               event_cb = malloc(sizeof(struct dev_event_callback));
+               if (event_cb != NULL) {
+                       event_cb->cb_fn = cb_fn;
+                       event_cb->cb_arg = cb_arg;
+                       event_cb->active = 0;
+                       if (!device_name) {
+                               event_cb->dev_name = NULL;
+                       } else {
+                               event_cb->dev_name = strdup(device_name);
+                               if (event_cb->dev_name == NULL) {
+                                       ret = -ENOMEM;
+                                       goto error;
                                }
                        }
+                       TAILQ_INSERT_TAIL(&dev_event_cbs, event_cb, next);
+               } else {
+                       RTE_LOG(ERR, EAL,
+                               "Failed to allocate memory for device "
+                               "event callback.");
+                       ret = -ENOMEM;
+                       goto error;
                }
+       } else {
+               RTE_LOG(ERR, EAL,
+                       "The callback is already exist, no need "
+                       "to register again.\n");
+               ret = -EEXIST;
+       }
 
-               /* If initializing pre PCI probe, then we don't expect a bonded driver
-                * to be found */
-               if (init_pri == PMD_INIT_PRE_PCI_PROBE &&
-                               strncmp(PMD_BOND_NAME, devargs->virtual.drv_name,
-                                       strlen(PMD_BOND_NAME)) != 0) {
-                       if (driver == NULL) {
-                               rte_panic("no driver found for virtual device %s\n",
-                                       devargs->virtual.drv_name);
-                       }
-               } else if (init_pri == PMD_INIT_POST_PCI_PROBE &&
-                               strncmp(PMD_BOND_NAME, devargs->virtual.drv_name,
-                                       strlen(PMD_BOND_NAME)) == 0) {
-                       if (driver == NULL) {
-                               rte_panic("no driver found for bonded device %s\n",
-                                       devargs->virtual.drv_name);
+       rte_spinlock_unlock(&dev_event_lock);
+       return 0;
+error:
+       free(event_cb);
+       rte_spinlock_unlock(&dev_event_lock);
+       return ret;
+}
+
+int
+rte_dev_event_callback_unregister(const char *device_name,
+                                 rte_dev_event_cb_fn cb_fn,
+                                 void *cb_arg)
+{
+       int ret = 0;
+       struct dev_event_callback *event_cb, *next;
+
+       if (!cb_fn)
+               return -EINVAL;
+
+       rte_spinlock_lock(&dev_event_lock);
+       /*walk through the callbacks and remove all that match. */
+       for (event_cb = TAILQ_FIRST(&dev_event_cbs); event_cb != NULL;
+            event_cb = next) {
+
+               next = TAILQ_NEXT(event_cb, next);
+
+               if (device_name != NULL && event_cb->dev_name != NULL) {
+                       if (!strcmp(event_cb->dev_name, device_name)) {
+                               if (event_cb->cb_fn != cb_fn ||
+                                   (cb_arg != (void *)-1 &&
+                                   event_cb->cb_arg != cb_arg))
+                                       continue;
                        }
+               } else if (device_name != NULL) {
+                       continue;
+               }
+
+               /*
+                * if this callback is not executing right now,
+                * then remove it.
+                */
+               if (event_cb->active == 0) {
+                       TAILQ_REMOVE(&dev_event_cbs, event_cb, next);
+                       free(event_cb);
+                       ret++;
+               } else {
+                       continue;
                }
        }
+       rte_spinlock_unlock(&dev_event_lock);
+       return ret;
+}
+
+void
+rte_dev_event_callback_process(const char *device_name,
+                              enum rte_dev_event_type event)
+{
+       struct dev_event_callback *cb_lst;
+
+       if (device_name == NULL)
+               return;
 
-       /* Once the vdevs are initialized, start calling all the pdev drivers */
-       if (init_pri == PMD_INIT_PRE_PCI_PROBE) {
-               TAILQ_FOREACH(driver, &dev_driver_list, next) {
-                       if (driver->type != PMD_PDEV)
+       rte_spinlock_lock(&dev_event_lock);
+
+       TAILQ_FOREACH(cb_lst, &dev_event_cbs, next) {
+               if (cb_lst->dev_name) {
+                       if (strcmp(cb_lst->dev_name, device_name))
                                continue;
-                       /* PDEV drivers don't get passed any parameters */
-                       driver->init(NULL, NULL);
                }
+               cb_lst->active = 1;
+               rte_spinlock_unlock(&dev_event_lock);
+               cb_lst->cb_fn(device_name, event,
+                               cb_lst->cb_arg);
+               rte_spinlock_lock(&dev_event_lock);
+               cb_lst->active = 0;
        }
-       return 0;
+       rte_spinlock_unlock(&dev_event_lock);
+}
+
+int
+rte_dev_iterator_init(struct rte_dev_iterator *it,
+                     const char *dev_str)
+{
+       struct rte_devargs devargs;
+       struct rte_class *cls = NULL;
+       struct rte_bus *bus = NULL;
+
+       /* Having both bus_str and cls_str NULL is illegal,
+        * marking this iterator as invalid unless
+        * everything goes well.
+        */
+       it->bus_str = NULL;
+       it->cls_str = NULL;
+
+       devargs.data = dev_str;
+       if (rte_devargs_layers_parse(&devargs, dev_str))
+               goto get_out;
+
+       bus = devargs.bus;
+       cls = devargs.cls;
+       /* The string should have at least
+        * one layer specified.
+        */
+       if (bus == NULL && cls == NULL) {
+               RTE_LOG(ERR, EAL,
+                       "Either bus or class must be specified.\n");
+               rte_errno = EINVAL;
+               goto get_out;
+       }
+       if (bus != NULL && bus->dev_iterate == NULL) {
+               RTE_LOG(ERR, EAL, "Bus %s not supported\n", bus->name);
+               rte_errno = ENOTSUP;
+               goto get_out;
+       }
+       if (cls != NULL && cls->dev_iterate == NULL) {
+               RTE_LOG(ERR, EAL, "Class %s not supported\n", cls->name);
+               rte_errno = ENOTSUP;
+               goto get_out;
+       }
+       it->bus_str = devargs.bus_str;
+       it->cls_str = devargs.cls_str;
+       it->dev_str = dev_str;
+       it->bus = bus;
+       it->cls = cls;
+       it->device = NULL;
+       it->class_device = NULL;
+get_out:
+       return -rte_errno;
+}
+
+static char *
+dev_str_sane_copy(const char *str)
+{
+       size_t end;
+       char *copy;
+
+       end = strcspn(str, ",/");
+       if (str[end] == ',') {
+               copy = strdup(&str[end + 1]);
+       } else {
+               /* '/' or '\0' */
+               copy = strdup("");
+       }
+       if (copy == NULL) {
+               rte_errno = ENOMEM;
+       } else {
+               char *slash;
+
+               slash = strchr(copy, '/');
+               if (slash != NULL)
+                       slash[0] = '\0';
+       }
+       return copy;
+}
+
+static int
+class_next_dev_cmp(const struct rte_class *cls,
+                  const void *ctx)
+{
+       struct rte_dev_iterator *it;
+       const char *cls_str = NULL;
+       void *dev;
+
+       if (cls->dev_iterate == NULL)
+               return 1;
+       it = ITCTX(ctx);
+       cls_str = CLSCTX(ctx);
+       dev = it->class_device;
+       /* it->cls_str != NULL means a class
+        * was specified in the devstr.
+        */
+       if (it->cls_str != NULL && cls != it->cls)
+               return 1;
+       /* If an error occurred previously,
+        * no need to test further.
+        */
+       if (rte_errno != 0)
+               return -1;
+       dev = cls->dev_iterate(dev, cls_str, it);
+       it->class_device = dev;
+       return dev == NULL;
+}
+
+static int
+bus_next_dev_cmp(const struct rte_bus *bus,
+                const void *ctx)
+{
+       struct rte_device *dev = NULL;
+       struct rte_class *cls = NULL;
+       struct rte_dev_iterator *it;
+       const char *bus_str = NULL;
+
+       if (bus->dev_iterate == NULL)
+               return 1;
+       it = ITCTX(ctx);
+       bus_str = BUSCTX(ctx);
+       dev = it->device;
+       /* it->bus_str != NULL means a bus
+        * was specified in the devstr.
+        */
+       if (it->bus_str != NULL && bus != it->bus)
+               return 1;
+       /* If an error occurred previously,
+        * no need to test further.
+        */
+       if (rte_errno != 0)
+               return -1;
+       if (it->cls_str == NULL) {
+               dev = bus->dev_iterate(dev, bus_str, it);
+               goto end;
+       }
+       /* cls_str != NULL */
+       if (dev == NULL) {
+next_dev_on_bus:
+               dev = bus->dev_iterate(dev, bus_str, it);
+               it->device = dev;
+       }
+       if (dev == NULL)
+               return 1;
+       if (it->cls != NULL)
+               cls = TAILQ_PREV(it->cls, rte_class_list, next);
+       cls = rte_class_find(cls, class_next_dev_cmp, ctx);
+       if (cls != NULL) {
+               it->cls = cls;
+               goto end;
+       }
+       goto next_dev_on_bus;
+end:
+       it->device = dev;
+       return dev == NULL;
+}
+struct rte_device *
+rte_dev_iterator_next(struct rte_dev_iterator *it)
+{
+       struct rte_bus *bus = NULL;
+       int old_errno = rte_errno;
+       char *bus_str = NULL;
+       char *cls_str = NULL;
+
+       rte_errno = 0;
+       if (it->bus_str == NULL && it->cls_str == NULL) {
+               /* Invalid iterator. */
+               rte_errno = EINVAL;
+               return NULL;
+       }
+       if (it->bus != NULL)
+               bus = TAILQ_PREV(it->bus, rte_bus_list, next);
+       if (it->bus_str != NULL) {
+               bus_str = dev_str_sane_copy(it->bus_str);
+               if (bus_str == NULL)
+                       goto out;
+       }
+       if (it->cls_str != NULL) {
+               cls_str = dev_str_sane_copy(it->cls_str);
+               if (cls_str == NULL)
+                       goto out;
+       }
+       while ((bus = rte_bus_find(bus, bus_next_dev_cmp,
+                                  CTX(it, bus_str, cls_str)))) {
+               if (it->device != NULL) {
+                       it->bus = bus;
+                       goto out;
+               }
+               if (it->bus_str != NULL ||
+                   rte_errno != 0)
+                       break;
+       }
+       if (rte_errno == 0)
+               rte_errno = old_errno;
+out:
+       free(bus_str);
+       free(cls_str);
+       return it->device;
+}
+
+int
+rte_dev_dma_map(struct rte_device *dev, void *addr, uint64_t iova,
+               size_t len)
+{
+       if (dev->bus->dma_map == NULL || len == 0) {
+               rte_errno = ENOTSUP;
+               return -1;
+       }
+       /* Memory must be registered through rte_extmem_* APIs */
+       if (rte_mem_virt2memseg_list(addr) == NULL) {
+               rte_errno = EINVAL;
+               return -1;
+       }
+
+       return dev->bus->dma_map(dev, addr, iova, len);
+}
+
+int
+rte_dev_dma_unmap(struct rte_device *dev, void *addr, uint64_t iova,
+                 size_t len)
+{
+       if (dev->bus->dma_unmap == NULL || len == 0) {
+               rte_errno = ENOTSUP;
+               return -1;
+       }
+       /* Memory must be registered through rte_extmem_* APIs */
+       if (rte_mem_virt2memseg_list(addr) == NULL) {
+               rte_errno = EINVAL;
+               return -1;
+       }
+
+       return dev->bus->dma_unmap(dev, addr, iova, len);
 }