// Copyright (2019-2022) Paul Scherrer Institute
// SPDX-License-Identifier: GPL-3.0-or-later

#ifdef JFJOCH_USE_IBVERBS

#include <thread>
#include <chrono>

#include "IBWrappers.h"
#include "../../common/JFJochException.h"

IBContext::IBContext(const std::string &dev_name) {
    struct ibv_device **dev_list;
    int num_devices;

    dev_list = ibv_get_device_list(&num_devices);

    if (dev_list == nullptr) throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to get IB devices list.");

    int selected = -1;
    for (int i = 0; i < num_devices; i++) {
        std::string tmp = std::string(ibv_get_device_name(dev_list[i]));
        if (dev_name == tmp) selected = i;
    }

    if (selected == -1) throw JFJochException(JFJochExceptionCategory::IBVerbs, "IB device not found.");

    context = ibv_open_device(dev_list[selected]);
    if (context == nullptr)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to open context for IB device.");

    ibv_free_device_list(dev_list);

    if (GetState() != IBV_PORT_ACTIVE) {
        ibv_close_device(context);
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "IB port is not open");
    }
}

IBContext::~IBContext() {
    ibv_close_device(context);
}

ibv_port_state IBContext::GetState() {
    ibv_port_attr port_attr{};
    if(ibv_query_port(context, 1, &port_attr) != 0)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Cannot query port");
    return port_attr.state;
}

uint16_t IBContext::GetLid() {
    ibv_port_attr port_attr{};
    if(ibv_query_port(context, 1, &port_attr) != 0)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Cannot query port");
    return port_attr.lid;
}

ibv_context *IBContext::GetPointer() {
    return context;
}

IBCompletionQueue::IBCompletionQueue(IBContext &context, int minimum_size) {
    cq = ibv_create_cq(context.GetPointer(), minimum_size, nullptr, nullptr, 0);
    if (cq == nullptr)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to create completion queue.");
}

int IBCompletionQueue::Poll(int64_t &id, size_t &compl_size) {
    ibv_wc wc{};
    int num_comp = ibv_poll_cq(cq, 1, &wc);

    // Error in CQ polling
    if (num_comp < 0)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed polling IB Verbs completion queue");
    else if (num_comp > 0) {
        // Check for error in work completion
        if (wc.status == IBV_WC_RETRY_EXC_ERR)
            throw JFJochException(JFJochExceptionCategory::IBVerbs, "Remote party can be disconnected or failed (transport retry counter exceeded status in CQ)");
        else if (wc.status != IBV_WC_SUCCESS)
            throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed status of IB Verbs send request " + std::to_string(wc.status), wc.status);
        else if (!(wc.wc_flags & IBV_WC_IP_CSUM_OK))
            compl_size = 0;
        else
            // Frame length in bytes
            compl_size = wc.byte_len;

        // Location in buffer is based on work request ID
        id = wc.wr_id;
    }
    return num_comp;
}

ibv_cq *IBCompletionQueue::GetPointer() {
    return cq;
}

IBCompletionQueue::~IBCompletionQueue() {
    ibv_destroy_cq(cq);
}

IBQueuePair::IBQueuePair(IBProtectionDomain &pd, IBCompletionQueue &cq, size_t send_queue_size,
                         size_t receive_queue_size) {
    ibv_qp_init_attr qp_init_attr{};
    memset(&qp_init_attr, 0, sizeof (qp_init_attr));
    qp_init_attr.send_cq = cq.GetPointer();
    qp_init_attr.recv_cq = cq.GetPointer();
    qp_init_attr.qp_type = IBV_QPT_RAW_PACKET;
    qp_init_attr.cap.max_send_wr = send_queue_size;
    qp_init_attr.cap.max_recv_wr = receive_queue_size;
    qp_init_attr.cap.max_send_sge = 1; // No scatter/gather operations

    qp = ibv_create_qp(pd.GetPointer(), &qp_init_attr);
    if (qp == nullptr)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to create IB queue pair.");
}

uint32_t IBQueuePair::GetNumber() {
    return qp->qp_num;
}

void IBQueuePair::Init() {
    ibv_qp_attr qp_attr{};
    memset(&qp_attr, 0, sizeof(qp_attr));

    int qp_flags = IBV_QP_STATE | IBV_QP_PORT |IBV_QP_PKEY_INDEX | IBV_QP_ACCESS_FLAGS;
    qp_attr.qp_state = IBV_QPS_INIT;
    qp_attr.port_num = 1;
    qp_attr.qp_access_flags = 0;
    qp_attr.pkey_index = 0;

    if (ibv_modify_qp(qp, &qp_attr, qp_flags))
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed modify IB queue pair to init.");
}

void IBQueuePair::ReadyToReceive() {
    int qp_flags = IBV_QP_STATE ;

    ibv_qp_attr qp_attr{};
    memset(&qp_attr, 0, sizeof(qp_attr));

    qp_attr.qp_state           = IBV_QPS_RTR;

    if (ibv_modify_qp(qp, &qp_attr, qp_flags))
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to set IB queue pair to ready to receive ");
}

void IBQueuePair::ReadyToSend() {
    int qp_flags = IBV_QP_STATE ;

    ibv_qp_attr qp_attr{};
    memset(&qp_attr, 0, sizeof(qp_attr));

    qp_attr.qp_state         = IBV_QPS_RTS;

    if (ibv_modify_qp(qp, &qp_attr, qp_flags))
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to set IB queue pair to ready to send");
}

void IBQueuePair::Reset() {
    int qp_flags = IBV_QP_STATE;

    ibv_qp_attr qp_attr{};
    memset(&qp_attr, 0, sizeof(qp_attr));

    qp_attr.qp_state = IBV_QPS_RESET;

    if (ibv_modify_qp(qp, &qp_attr, qp_flags))
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed modify IB queue pair to reset.");
}

void IBQueuePair::PostReceiveWR(IBMemoryRegion &mr, uint32_t location, void *pointer, size_t size) {

    ibv_sge ib_sg_entry{};
    ibv_recv_wr ib_wr{};
    ibv_recv_wr *ib_bad_recv_wr = nullptr;

    // pointer to packet buffer size and memory key of each packet buffer
    ib_sg_entry.length = size;
    ib_sg_entry.lkey = mr.GetLocalKey();

    ib_wr.num_sge = 1;
    ib_wr.sg_list = &ib_sg_entry;
    ib_wr.next = nullptr;
    ib_sg_entry.addr = (uintptr_t)(pointer);
    ib_wr.wr_id = location;

    int ret;
    while ((ret = ibv_post_recv(qp, &ib_wr, &ib_bad_recv_wr))) {
        if (ret != ENOMEM)
            throw JFJochException(JFJochExceptionCategory::IBVerbs, "Receiving with IB Verbs failed ", ret);
        // ENONEM is not enough location in receive queue; just wait
        std::this_thread::sleep_for(std::chrono::microseconds(1));
    }
}

void IBQueuePair::PostInlineSendWR(void *pointer, size_t size) {
    // Send the frame via RDMA
    ibv_sge ib_sg{};
    ibv_send_wr ib_wr{};
    ibv_send_wr *ib_bad_wr = nullptr;

    memset(&ib_sg, 0, sizeof(ib_sg));
    memset(&ib_wr, 0, sizeof(ib_wr));

    ib_sg.addr	 = (uintptr_t)(pointer);
    ib_sg.length = size;

    ib_wr.wr_id      = UINT64_MAX;
    ib_wr.sg_list    = &ib_sg;
    ib_wr.num_sge    = 1;

    ib_wr.opcode     = IBV_WR_SEND;
    ib_wr.send_flags = IBV_SEND_INLINE;

    int ret;
    while ((ret = ibv_post_send(qp, &ib_wr, &ib_bad_wr))) {
        if (ret != ENOMEM)
            throw JFJochException(JFJochExceptionCategory::IBVerbs, "Sending with IB Verbs failed", ret);
        // ENONEM is not enough location in send queue; just wait
        std::this_thread::sleep_for(std::chrono::microseconds(1));
    }
}

void IBQueuePair::FlowSteering(uint64_t mac_addr, uint32_t ipv4) {
    uint8_t dst_mac_addr[6];
    for (int i = 0; i < 6; i++)
        dst_mac_addr[i] = (mac_addr & (0xFF << (i*8))) >> (i * 8);

    struct raw_eth_flow_attr {
        struct ibv_flow_attr attr;
        struct ibv_flow_spec_eth spec_eth;
        struct ibv_flow_spec_ipv4 spec_ipv4;
    } __attribute__((packed)) flow_attr = {
            .attr = {
                    .comp_mask = 0,
                    .type = IBV_FLOW_ATTR_NORMAL,
                    .size = sizeof(flow_attr),
                    .priority = 0,
                    .num_of_specs = 2,
                    .port = 1,
                    .flags = 0,
            },
            .spec_eth = {
                    .type = IBV_FLOW_SPEC_ETH,
                    .size = sizeof(struct ibv_flow_spec_eth),
                    .val = {
                            .dst_mac = {
                                    dst_mac_addr[0],
                                    dst_mac_addr[1],
                                    dst_mac_addr[2],
                                    dst_mac_addr[3],
                                    dst_mac_addr[4],
                                    dst_mac_addr[5]
                                    },
                            .src_mac = {0,0,0,0,0,0},
                            .ether_type = 0x0800,
                            .vlan_tag = 0x0
                    },
                    .mask = {
                            .dst_mac = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF},
                            .src_mac = {0,0,0,0,0,0},
                            .ether_type = 0xFFFF,
                            .vlan_tag = 0x0
                    }
            },
            .spec_ipv4 = {
                    .type = IBV_FLOW_SPEC_IPV4,
                    .size = sizeof(struct ibv_flow_spec_ipv4),
                    .val = {
                            .src_ip = 0,
                            .dst_ip = ipv4
                    },
                    .mask = {
                            .src_ip = 0,
                            .dst_ip = 0xFFFFFFFF
                    }
            }
    };

    flow = ibv_create_flow(qp, &flow_attr.attr);
    if (flow == nullptr)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to set IB flow steering");
}

IBQueuePair::~IBQueuePair() {
    if (flow)
        ibv_destroy_flow(flow);
    ibv_destroy_qp(qp);
}

IBProtectionDomain::IBProtectionDomain(IBContext &context) {
    pd = ibv_alloc_pd(context.GetPointer());
    if (pd == nullptr)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to allocate IB protection domain.");
}

IBProtectionDomain::~IBProtectionDomain() {
    ibv_dealloc_pd(pd);
}

ibv_pd *IBProtectionDomain::GetPointer() {
    return pd;
}

IBMemoryRegion::IBMemoryRegion(IBProtectionDomain &pd, void *pointer, size_t size) {
    buffer_mr = ibv_reg_mr(pd.GetPointer(), pointer, size, IBV_ACCESS_LOCAL_WRITE);

    if (buffer_mr == nullptr)
        throw JFJochException(JFJochExceptionCategory::IBVerbs, "Failed to register IB memory region.");
}

uint32_t IBMemoryRegion::GetLocalKey() {
    return buffer_mr->lkey;
}

uint32_t IBMemoryRegion::GetRemoteKey() {
    return buffer_mr->rkey;
}

IBMemoryRegion::~IBMemoryRegion() {
    ibv_dereg_mr(buffer_mr);
}

#endif //JFJOCH_USE_IBVERBS