/* 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_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"

/**
 * 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 */
};

/** @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)
{
        const char *name = _name;

        return strcmp(dev->name, name);
}

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)
{

        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
local_dev_probe(const char *devargs, struct rte_device **new_dev)
{
        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;

        /* 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.
         */

        ret = dev->bus->plug(dev);
        if (ret > 0)
                ret = -ENOTSUP;

        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;
        }

        *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 < 0) ? ret : -ENOENT;
        }

        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: */

        /* 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");
                event_cb = NULL;
                ret = -EEXIST;
                goto error;
        }

        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->dev_name);
                        free(event_cb);
                        ret++;
                } else {
                        ret = -EAGAIN;
                        break;
                }
        }

        /* this callback is not be registered */
        if (ret == 0)
                ret = -ENOENT;

        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;

        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;
                }
                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;
        }
        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);
}