// SPDX-License-Identifier: BSD-3-Clause-Clear
/*
 * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
 * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
 */

#include "core.h"
#include "peer.h"
#include "debug.h"

static struct ath11k_peer *ath11k_peer_find_list_by_id(struct ath11k_base *ab,
                                                       int peer_id)
{
        struct ath11k_peer *peer;

        lockdep_assert_held(&ab->base_lock);

        list_for_each_entry(peer, &ab->peers, list) {
                if (peer->peer_id != peer_id)
                        continue;

                return peer;
        }

        return NULL;
}

struct ath11k_peer *ath11k_peer_find(struct ath11k_base *ab, int vdev_id,
                                     const u8 *addr)
{
        struct ath11k_peer *peer;

        lockdep_assert_held(&ab->base_lock);

        list_for_each_entry(peer, &ab->peers, list) {
                if (peer->vdev_id != vdev_id)
                        continue;
                if (!ether_addr_equal(peer->addr, addr))
                        continue;

                return peer;
        }

        return NULL;
}

struct ath11k_peer *ath11k_peer_find_by_addr(struct ath11k_base *ab,
                                             const u8 *addr)
{
        struct ath11k_peer *peer;

        lockdep_assert_held(&ab->base_lock);

        if (!ab->rhead_peer_addr)
                return NULL;

        peer = rhashtable_lookup_fast(ab->rhead_peer_addr, addr,
                                      ab->rhash_peer_addr_param);

        return peer;
}

struct ath11k_peer *ath11k_peer_find_by_id(struct ath11k_base *ab,
                                           int peer_id)
{
        struct ath11k_peer *peer;

        lockdep_assert_held(&ab->base_lock);

        if (!ab->rhead_peer_id)
                return NULL;

        peer = rhashtable_lookup_fast(ab->rhead_peer_id, &peer_id,
                                      ab->rhash_peer_id_param);

        return peer;
}

struct ath11k_peer *ath11k_peer_find_by_vdev_id(struct ath11k_base *ab,
                                                int vdev_id)
{
        struct ath11k_peer *peer;

        spin_lock_bh(&ab->base_lock);

        list_for_each_entry(peer, &ab->peers, list) {
                if (vdev_id == peer->vdev_id) {
                        spin_unlock_bh(&ab->base_lock);
                        return peer;
                }
        }
        spin_unlock_bh(&ab->base_lock);
        return NULL;
}

void ath11k_peer_unmap_event(struct ath11k_base *ab, u16 peer_id)
{
        struct ath11k_peer *peer;

        spin_lock_bh(&ab->base_lock);

        peer = ath11k_peer_find_list_by_id(ab, peer_id);
        if (!peer) {
                ath11k_warn(ab, "peer-unmap-event: unknown peer id %d\n",
                            peer_id);
                goto exit;
        }

        ath11k_dbg(ab, ATH11K_DBG_DP_HTT, "peer unmap vdev %d peer %pM id %d\n",
                   peer->vdev_id, peer->addr, peer_id);

        list_del(&peer->list);
        kfree(peer);
        wake_up(&ab->peer_mapping_wq);

exit:
        spin_unlock_bh(&ab->base_lock);
}

void ath11k_peer_map_event(struct ath11k_base *ab, u8 vdev_id, u16 peer_id,
                           u8 *mac_addr, u16 ast_hash, u16 hw_peer_id)
{
        struct ath11k_peer *peer;

        spin_lock_bh(&ab->base_lock);
        peer = ath11k_peer_find(ab, vdev_id, mac_addr);
        if (!peer) {
                peer = kzalloc_obj(*peer, GFP_ATOMIC);
                if (!peer)
                        goto exit;

                peer->vdev_id = vdev_id;
                peer->peer_id = peer_id;
                peer->ast_hash = ast_hash;
                peer->hw_peer_id = hw_peer_id;
                ether_addr_copy(peer->addr, mac_addr);
                list_add(&peer->list, &ab->peers);
                wake_up(&ab->peer_mapping_wq);
        }

        ath11k_dbg(ab, ATH11K_DBG_DP_HTT, "peer map vdev %d peer %pM id %d\n",
                   vdev_id, mac_addr, peer_id);

exit:
        spin_unlock_bh(&ab->base_lock);
}

static int ath11k_wait_for_peer_common(struct ath11k_base *ab, int vdev_id,
                                       const u8 *addr, bool expect_mapped)
{
        int ret;

        ret = wait_event_timeout(ab->peer_mapping_wq, ({
                                bool mapped;

                                spin_lock_bh(&ab->base_lock);
                                mapped = !!ath11k_peer_find(ab, vdev_id, addr);
                                spin_unlock_bh(&ab->base_lock);

                                (mapped == expect_mapped ||
                                 test_bit(ATH11K_FLAG_CRASH_FLUSH, &ab->dev_flags));
                                }), 3 * HZ);

        if (ret <= 0)
                return -ETIMEDOUT;

        return 0;
}

static inline int ath11k_peer_rhash_insert(struct ath11k_base *ab,
                                           struct rhashtable *rtbl,
                                           struct rhash_head *rhead,
                                           struct rhashtable_params *params,
                                           void *key)
{
        struct ath11k_peer *tmp;

        lockdep_assert_held(&ab->tbl_mtx_lock);

        tmp = rhashtable_lookup_get_insert_fast(rtbl, rhead, *params);

        if (!tmp)
                return 0;
        else if (IS_ERR(tmp))
                return PTR_ERR(tmp);
        else
                return -EEXIST;
}

static inline int ath11k_peer_rhash_remove(struct ath11k_base *ab,
                                           struct rhashtable *rtbl,
                                           struct rhash_head *rhead,
                                           struct rhashtable_params *params)
{
        int ret;

        lockdep_assert_held(&ab->tbl_mtx_lock);

        ret = rhashtable_remove_fast(rtbl, rhead, *params);
        if (ret && ret != -ENOENT)
                return ret;

        return 0;
}

static int ath11k_peer_rhash_add(struct ath11k_base *ab, struct ath11k_peer *peer)
{
        int ret;

        lockdep_assert_held(&ab->base_lock);
        lockdep_assert_held(&ab->tbl_mtx_lock);

        if (!ab->rhead_peer_id || !ab->rhead_peer_addr)
                return -EPERM;

        ret = ath11k_peer_rhash_insert(ab, ab->rhead_peer_id, &peer->rhash_id,
                                       &ab->rhash_peer_id_param, &peer->peer_id);
        if (ret) {
                ath11k_warn(ab, "failed to add peer %pM with id %d in rhash_id ret %d\n",
                            peer->addr, peer->peer_id, ret);
                return ret;
        }

        ret = ath11k_peer_rhash_insert(ab, ab->rhead_peer_addr, &peer->rhash_addr,
                                       &ab->rhash_peer_addr_param, &peer->addr);
        if (ret) {
                ath11k_warn(ab, "failed to add peer %pM with id %d in rhash_addr ret %d\n",
                            peer->addr, peer->peer_id, ret);
                goto err_clean;
        }

        return 0;

err_clean:
        ath11k_peer_rhash_remove(ab, ab->rhead_peer_id, &peer->rhash_id,
                                 &ab->rhash_peer_id_param);
        return ret;
}

void ath11k_peer_cleanup(struct ath11k *ar, u32 vdev_id)
{
        struct ath11k_peer *peer, *tmp;
        struct ath11k_base *ab = ar->ab;

        lockdep_assert_held(&ar->conf_mutex);

        mutex_lock(&ab->tbl_mtx_lock);
        spin_lock_bh(&ab->base_lock);
        list_for_each_entry_safe(peer, tmp, &ab->peers, list) {
                if (peer->vdev_id != vdev_id)
                        continue;

                ath11k_warn(ab, "removing stale peer %pM from vdev_id %d\n",
                            peer->addr, vdev_id);

                ath11k_peer_rhash_delete(ab, peer);
                list_del(&peer->list);
                kfree(peer);
                ar->num_peers--;
        }

        spin_unlock_bh(&ab->base_lock);
        mutex_unlock(&ab->tbl_mtx_lock);
}

static int ath11k_wait_for_peer_deleted(struct ath11k *ar, int vdev_id, const u8 *addr)
{
        return ath11k_wait_for_peer_common(ar->ab, vdev_id, addr, false);
}

int ath11k_wait_for_peer_delete_done(struct ath11k *ar, u32 vdev_id,
                                     const u8 *addr)
{
        int ret;
        unsigned long time_left;

        ret = ath11k_wait_for_peer_deleted(ar, vdev_id, addr);
        if (ret) {
                ath11k_warn(ar->ab, "failed wait for peer deleted");
                return ret;
        }

        time_left = wait_for_completion_timeout(&ar->peer_delete_done,
                                                3 * HZ);
        if (time_left == 0) {
                ath11k_warn(ar->ab, "Timeout in receiving peer delete response\n");
                return -ETIMEDOUT;
        }

        return 0;
}

static int __ath11k_peer_delete(struct ath11k *ar, u32 vdev_id, const u8 *addr)
{
        int ret;
        struct ath11k_peer *peer;
        struct ath11k_base *ab = ar->ab;

        lockdep_assert_held(&ar->conf_mutex);

        mutex_lock(&ab->tbl_mtx_lock);
        spin_lock_bh(&ab->base_lock);

        peer = ath11k_peer_find_by_addr(ab, addr);
        /* Check if the found peer is what we want to remove.
         * While the sta is transitioning to another band we may
         * have 2 peer with the same addr assigned to different
         * vdev_id. Make sure we are deleting the correct peer.
         */
        if (peer && peer->vdev_id == vdev_id)
                ath11k_peer_rhash_delete(ab, peer);

        /* Fallback to peer list search if the correct peer can't be found.
         * Skip the deletion of the peer from the rhash since it has already
         * been deleted in peer add.
         */
        if (!peer)
                peer = ath11k_peer_find(ab, vdev_id, addr);

        if (!peer) {
                spin_unlock_bh(&ab->base_lock);
                mutex_unlock(&ab->tbl_mtx_lock);

                ath11k_warn(ab,
                            "failed to find peer vdev_id %d addr %pM in delete\n",
                            vdev_id, addr);
                return -EINVAL;
        }

        spin_unlock_bh(&ab->base_lock);
        mutex_unlock(&ab->tbl_mtx_lock);

        reinit_completion(&ar->peer_delete_done);

        ret = ath11k_wmi_send_peer_delete_cmd(ar, addr, vdev_id);
        if (ret) {
                ath11k_warn(ab,
                            "failed to delete peer vdev_id %d addr %pM ret %d\n",
                            vdev_id, addr, ret);
                return ret;
        }

        ret = ath11k_wait_for_peer_delete_done(ar, vdev_id, addr);
        if (ret)
                return ret;

        return 0;
}

int ath11k_peer_delete(struct ath11k *ar, u32 vdev_id, u8 *addr)
{
        int ret;

        lockdep_assert_held(&ar->conf_mutex);

        ret = __ath11k_peer_delete(ar, vdev_id, addr);
        if (ret)
                return ret;

        ar->num_peers--;

        return 0;
}

static int ath11k_wait_for_peer_created(struct ath11k *ar, int vdev_id, const u8 *addr)
{
        return ath11k_wait_for_peer_common(ar->ab, vdev_id, addr, true);
}

int ath11k_peer_create(struct ath11k *ar, struct ath11k_vif *arvif,
                       struct ieee80211_sta *sta, struct peer_create_params *param)
{
        struct ath11k_peer *peer;
        struct ath11k_sta *arsta;
        int ret, fbret;

        lockdep_assert_held(&ar->conf_mutex);

        if (ar->num_peers > (ar->max_num_peers - 1)) {
                ath11k_warn(ar->ab,
                            "failed to create peer due to insufficient peer entry resource in firmware\n");
                return -ENOBUFS;
        }

        mutex_lock(&ar->ab->tbl_mtx_lock);
        spin_lock_bh(&ar->ab->base_lock);
        peer = ath11k_peer_find_by_addr(ar->ab, param->peer_addr);
        if (peer) {
                if (peer->vdev_id == param->vdev_id) {
                        spin_unlock_bh(&ar->ab->base_lock);
                        mutex_unlock(&ar->ab->tbl_mtx_lock);
                        return -EINVAL;
                }

                /* Assume sta is transitioning to another band.
                 * Remove here the peer from rhash.
                 */
                ath11k_peer_rhash_delete(ar->ab, peer);
        }
        spin_unlock_bh(&ar->ab->base_lock);
        mutex_unlock(&ar->ab->tbl_mtx_lock);

        ret = ath11k_wmi_send_peer_create_cmd(ar, param);
        if (ret) {
                ath11k_warn(ar->ab,
                            "failed to send peer create vdev_id %d ret %d\n",
                            param->vdev_id, ret);
                return ret;
        }

        ret = ath11k_wait_for_peer_created(ar, param->vdev_id,
                                           param->peer_addr);
        if (ret)
                return ret;

        mutex_lock(&ar->ab->tbl_mtx_lock);
        spin_lock_bh(&ar->ab->base_lock);

        peer = ath11k_peer_find(ar->ab, param->vdev_id, param->peer_addr);
        if (!peer) {
                spin_unlock_bh(&ar->ab->base_lock);
                mutex_unlock(&ar->ab->tbl_mtx_lock);
                ath11k_warn(ar->ab, "failed to find peer %pM on vdev %i after creation\n",
                            param->peer_addr, param->vdev_id);

                ret = -ENOENT;
                goto cleanup;
        }

        ret = ath11k_peer_rhash_add(ar->ab, peer);
        if (ret) {
                spin_unlock_bh(&ar->ab->base_lock);
                mutex_unlock(&ar->ab->tbl_mtx_lock);
                goto cleanup;
        }

        peer->pdev_idx = ar->pdev_idx;
        peer->sta = sta;

        if (arvif->vif->type == NL80211_IFTYPE_STATION) {
                arvif->ast_hash = peer->ast_hash;
                arvif->ast_idx = peer->hw_peer_id;
        }

        peer->sec_type = HAL_ENCRYPT_TYPE_OPEN;
        peer->sec_type_grp = HAL_ENCRYPT_TYPE_OPEN;

        if (sta) {
                arsta = ath11k_sta_to_arsta(sta);
                arsta->tcl_metadata |= FIELD_PREP(HTT_TCL_META_DATA_TYPE, 0) |
                                       FIELD_PREP(HTT_TCL_META_DATA_PEER_ID,
                                                  peer->peer_id);

                /* set HTT extension valid bit to 0 by default */
                arsta->tcl_metadata &= ~HTT_TCL_META_DATA_VALID_HTT;
        }

        ar->num_peers++;

        spin_unlock_bh(&ar->ab->base_lock);
        mutex_unlock(&ar->ab->tbl_mtx_lock);

        return 0;

cleanup:
        fbret = __ath11k_peer_delete(ar, param->vdev_id, param->peer_addr);
        if (fbret)
                ath11k_warn(ar->ab, "failed peer %pM delete vdev_id %d fallback ret %d\n",
                            param->peer_addr, param->vdev_id, fbret);

        return ret;
}

int ath11k_peer_rhash_delete(struct ath11k_base *ab, struct ath11k_peer *peer)
{
        int ret;

        lockdep_assert_held(&ab->base_lock);
        lockdep_assert_held(&ab->tbl_mtx_lock);

        if (!ab->rhead_peer_id || !ab->rhead_peer_addr)
                return -EPERM;

        ret = ath11k_peer_rhash_remove(ab, ab->rhead_peer_addr, &peer->rhash_addr,
                                       &ab->rhash_peer_addr_param);
        if (ret) {
                ath11k_warn(ab, "failed to remove peer %pM id %d in rhash_addr ret %d\n",
                            peer->addr, peer->peer_id, ret);
                return ret;
        }

        ret = ath11k_peer_rhash_remove(ab, ab->rhead_peer_id, &peer->rhash_id,
                                       &ab->rhash_peer_id_param);
        if (ret) {
                ath11k_warn(ab, "failed to remove peer %pM id %d in rhash_id ret %d\n",
                            peer->addr, peer->peer_id, ret);
                return ret;
        }

        return 0;
}

static int ath11k_peer_rhash_id_tbl_init(struct ath11k_base *ab)
{
        struct rhashtable_params *param;
        struct rhashtable *rhash_id_tbl;
        int ret;
        size_t size;

        lockdep_assert_held(&ab->tbl_mtx_lock);

        if (ab->rhead_peer_id)
                return 0;

        size = sizeof(*ab->rhead_peer_id);
        rhash_id_tbl = kzalloc(size, GFP_KERNEL);
        if (!rhash_id_tbl) {
                ath11k_warn(ab, "failed to init rhash id table due to no mem (size %zu)\n",
                            size);
                return -ENOMEM;
        }

        param = &ab->rhash_peer_id_param;

        param->key_offset = offsetof(struct ath11k_peer, peer_id);
        param->head_offset = offsetof(struct ath11k_peer, rhash_id);
        param->key_len = sizeof_field(struct ath11k_peer, peer_id);
        param->automatic_shrinking = true;
        param->nelem_hint = ab->num_radios * TARGET_NUM_PEERS_PDEV(ab);

        ret = rhashtable_init(rhash_id_tbl, param);
        if (ret) {
                ath11k_warn(ab, "failed to init peer id rhash table %d\n", ret);
                goto err_free;
        }

        spin_lock_bh(&ab->base_lock);

        if (!ab->rhead_peer_id) {
                ab->rhead_peer_id = rhash_id_tbl;
        } else {
                spin_unlock_bh(&ab->base_lock);
                goto cleanup_tbl;
        }

        spin_unlock_bh(&ab->base_lock);

        return 0;

cleanup_tbl:
        rhashtable_destroy(rhash_id_tbl);
err_free:
        kfree(rhash_id_tbl);

        return ret;
}

static int ath11k_peer_rhash_addr_tbl_init(struct ath11k_base *ab)
{
        struct rhashtable_params *param;
        struct rhashtable *rhash_addr_tbl;
        int ret;
        size_t size;

        lockdep_assert_held(&ab->tbl_mtx_lock);

        if (ab->rhead_peer_addr)
                return 0;

        size = sizeof(*ab->rhead_peer_addr);
        rhash_addr_tbl = kzalloc(size, GFP_KERNEL);
        if (!rhash_addr_tbl) {
                ath11k_warn(ab, "failed to init rhash addr table due to no mem (size %zu)\n",
                            size);
                return -ENOMEM;
        }

        param = &ab->rhash_peer_addr_param;

        param->key_offset = offsetof(struct ath11k_peer, addr);
        param->head_offset = offsetof(struct ath11k_peer, rhash_addr);
        param->key_len = sizeof_field(struct ath11k_peer, addr);
        param->automatic_shrinking = true;
        param->nelem_hint = ab->num_radios * TARGET_NUM_PEERS_PDEV(ab);

        ret = rhashtable_init(rhash_addr_tbl, param);
        if (ret) {
                ath11k_warn(ab, "failed to init peer addr rhash table %d\n", ret);
                goto err_free;
        }

        spin_lock_bh(&ab->base_lock);

        if (!ab->rhead_peer_addr) {
                ab->rhead_peer_addr = rhash_addr_tbl;
        } else {
                spin_unlock_bh(&ab->base_lock);
                goto cleanup_tbl;
        }

        spin_unlock_bh(&ab->base_lock);

        return 0;

cleanup_tbl:
        rhashtable_destroy(rhash_addr_tbl);
err_free:
        kfree(rhash_addr_tbl);

        return ret;
}

static inline void ath11k_peer_rhash_id_tbl_destroy(struct ath11k_base *ab)
{
        lockdep_assert_held(&ab->tbl_mtx_lock);

        if (!ab->rhead_peer_id)
                return;

        rhashtable_destroy(ab->rhead_peer_id);
        kfree(ab->rhead_peer_id);
        ab->rhead_peer_id = NULL;
}

static inline void ath11k_peer_rhash_addr_tbl_destroy(struct ath11k_base *ab)
{
        lockdep_assert_held(&ab->tbl_mtx_lock);

        if (!ab->rhead_peer_addr)
                return;

        rhashtable_destroy(ab->rhead_peer_addr);
        kfree(ab->rhead_peer_addr);
        ab->rhead_peer_addr = NULL;
}

int ath11k_peer_rhash_tbl_init(struct ath11k_base *ab)
{
        int ret;

        mutex_lock(&ab->tbl_mtx_lock);

        ret = ath11k_peer_rhash_id_tbl_init(ab);
        if (ret)
                goto out;

        ret = ath11k_peer_rhash_addr_tbl_init(ab);
        if (ret)
                goto cleanup_tbl;

        mutex_unlock(&ab->tbl_mtx_lock);

        return 0;

cleanup_tbl:
        ath11k_peer_rhash_id_tbl_destroy(ab);
out:
        mutex_unlock(&ab->tbl_mtx_lock);
        return ret;
}

void ath11k_peer_rhash_tbl_destroy(struct ath11k_base *ab)
{
        mutex_lock(&ab->tbl_mtx_lock);

        ath11k_peer_rhash_addr_tbl_destroy(ab);
        ath11k_peer_rhash_id_tbl_destroy(ab);

        mutex_unlock(&ab->tbl_mtx_lock);
}