PM / sleep: Asynchronous threads for suspend_noirq

[linux/fpc-iii.git] / drivers / infiniband / hw / mlx5 / cq.c

/*
 * Copyright (c) 2013, Mellanox Technologies 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.
 */

#include <linux/kref.h>
#include <rdma/ib_umem.h>
#include "mlx5_ib.h"
#include "user.h"

static void mlx5_ib_cq_comp(struct mlx5_core_cq *cq)
{
        struct ib_cq *ibcq = &to_mibcq(cq)->ibcq;

        ibcq->comp_handler(ibcq, ibcq->cq_context);
}

static void mlx5_ib_cq_event(struct mlx5_core_cq *mcq, enum mlx5_event type)
{
        struct mlx5_ib_cq *cq = container_of(mcq, struct mlx5_ib_cq, mcq);
        struct mlx5_ib_dev *dev = to_mdev(cq->ibcq.device);
        struct ib_cq *ibcq = &cq->ibcq;
        struct ib_event event;

        if (type != MLX5_EVENT_TYPE_CQ_ERROR) {
                mlx5_ib_warn(dev, "Unexpected event type %d on CQ %06x\n",
                             type, mcq->cqn);
                return;
        }

        if (ibcq->event_handler) {
                event.device     = &dev->ib_dev;
                event.event      = IB_EVENT_CQ_ERR;
                event.element.cq = ibcq;
                ibcq->event_handler(&event, ibcq->cq_context);
        }
}

static void *get_cqe_from_buf(struct mlx5_ib_cq_buf *buf, int n, int size)
{
        return mlx5_buf_offset(&buf->buf, n * size);
}

static void *get_cqe(struct mlx5_ib_cq *cq, int n)
{
        return get_cqe_from_buf(&cq->buf, n, cq->mcq.cqe_sz);
}

static u8 sw_ownership_bit(int n, int nent)
{
        return (n & nent) ? 1 : 0;
}

static void *get_sw_cqe(struct mlx5_ib_cq *cq, int n)
{
        void *cqe = get_cqe(cq, n & cq->ibcq.cqe);
        struct mlx5_cqe64 *cqe64;

        cqe64 = (cq->mcq.cqe_sz == 64) ? cqe : cqe + 64;

        if (likely((cqe64->op_own) >> 4 != MLX5_CQE_INVALID) &&
            !((cqe64->op_own & MLX5_CQE_OWNER_MASK) ^ !!(n & (cq->ibcq.cqe + 1)))) {
                return cqe;
        } else {
                return NULL;
        }
}

static void *next_cqe_sw(struct mlx5_ib_cq *cq)
{
        return get_sw_cqe(cq, cq->mcq.cons_index);
}

static enum ib_wc_opcode get_umr_comp(struct mlx5_ib_wq *wq, int idx)
{
        switch (wq->wr_data[idx]) {
        case MLX5_IB_WR_UMR:
                return 0;

        case IB_WR_LOCAL_INV:
                return IB_WC_LOCAL_INV;

        case IB_WR_FAST_REG_MR:
                return IB_WC_FAST_REG_MR;

        default:
                pr_warn("unknown completion status\n");
                return 0;
        }
}

static void handle_good_req(struct ib_wc *wc, struct mlx5_cqe64 *cqe,
                            struct mlx5_ib_wq *wq, int idx)
{
        wc->wc_flags = 0;
        switch (be32_to_cpu(cqe->sop_drop_qpn) >> 24) {
        case MLX5_OPCODE_RDMA_WRITE_IMM:
                wc->wc_flags |= IB_WC_WITH_IMM;
        case MLX5_OPCODE_RDMA_WRITE:
                wc->opcode    = IB_WC_RDMA_WRITE;
                break;
        case MLX5_OPCODE_SEND_IMM:
                wc->wc_flags |= IB_WC_WITH_IMM;
        case MLX5_OPCODE_SEND:
        case MLX5_OPCODE_SEND_INVAL:
                wc->opcode    = IB_WC_SEND;
                break;
        case MLX5_OPCODE_RDMA_READ:
                wc->opcode    = IB_WC_RDMA_READ;
                wc->byte_len  = be32_to_cpu(cqe->byte_cnt);
                break;
        case MLX5_OPCODE_ATOMIC_CS:
                wc->opcode    = IB_WC_COMP_SWAP;
                wc->byte_len  = 8;
                break;
        case MLX5_OPCODE_ATOMIC_FA:
                wc->opcode    = IB_WC_FETCH_ADD;
                wc->byte_len  = 8;
                break;
        case MLX5_OPCODE_ATOMIC_MASKED_CS:
                wc->opcode    = IB_WC_MASKED_COMP_SWAP;
                wc->byte_len  = 8;
                break;
        case MLX5_OPCODE_ATOMIC_MASKED_FA:
                wc->opcode    = IB_WC_MASKED_FETCH_ADD;
                wc->byte_len  = 8;
                break;
        case MLX5_OPCODE_BIND_MW:
                wc->opcode    = IB_WC_BIND_MW;
                break;
        case MLX5_OPCODE_UMR:
                wc->opcode = get_umr_comp(wq, idx);
                break;
        }
}

enum {
        MLX5_GRH_IN_BUFFER = 1,
        MLX5_GRH_IN_CQE    = 2,
};

static void handle_responder(struct ib_wc *wc, struct mlx5_cqe64 *cqe,
                             struct mlx5_ib_qp *qp)
{
        struct mlx5_ib_dev *dev = to_mdev(qp->ibqp.device);
        struct mlx5_ib_srq *srq;
        struct mlx5_ib_wq *wq;
        u16 wqe_ctr;
        u8 g;

        if (qp->ibqp.srq || qp->ibqp.xrcd) {
                struct mlx5_core_srq *msrq = NULL;

                if (qp->ibqp.xrcd) {
                        msrq = mlx5_core_get_srq(&dev->mdev,
                                                 be32_to_cpu(cqe->srqn));
                        srq = to_mibsrq(msrq);
                } else {
                        srq = to_msrq(qp->ibqp.srq);
                }
                if (srq) {
                        wqe_ctr = be16_to_cpu(cqe->wqe_counter);
                        wc->wr_id = srq->wrid[wqe_ctr];
                        mlx5_ib_free_srq_wqe(srq, wqe_ctr);
                        if (msrq && atomic_dec_and_test(&msrq->refcount))
                                complete(&msrq->free);
                }
        } else {
                wq        = &qp->rq;
                wc->wr_id = wq->wrid[wq->tail & (wq->wqe_cnt - 1)];
                ++wq->tail;
        }
        wc->byte_len = be32_to_cpu(cqe->byte_cnt);

        switch (cqe->op_own >> 4) {
        case MLX5_CQE_RESP_WR_IMM:
                wc->opcode      = IB_WC_RECV_RDMA_WITH_IMM;
                wc->wc_flags    = IB_WC_WITH_IMM;
                wc->ex.imm_data = cqe->imm_inval_pkey;
                break;
        case MLX5_CQE_RESP_SEND:
                wc->opcode   = IB_WC_RECV;
                wc->wc_flags = 0;
                break;
        case MLX5_CQE_RESP_SEND_IMM:
                wc->opcode      = IB_WC_RECV;
                wc->wc_flags    = IB_WC_WITH_IMM;
                wc->ex.imm_data = cqe->imm_inval_pkey;
                break;
        case MLX5_CQE_RESP_SEND_INV:
                wc->opcode      = IB_WC_RECV;
                wc->wc_flags    = IB_WC_WITH_INVALIDATE;
                wc->ex.invalidate_rkey = be32_to_cpu(cqe->imm_inval_pkey);
                break;
        }
        wc->slid           = be16_to_cpu(cqe->slid);
        wc->sl             = (be32_to_cpu(cqe->flags_rqpn) >> 24) & 0xf;
        wc->src_qp         = be32_to_cpu(cqe->flags_rqpn) & 0xffffff;
        wc->dlid_path_bits = cqe->ml_path;
        g = (be32_to_cpu(cqe->flags_rqpn) >> 28) & 3;
        wc->wc_flags |= g ? IB_WC_GRH : 0;
        wc->pkey_index     = be32_to_cpu(cqe->imm_inval_pkey) & 0xffff;
}

static void dump_cqe(struct mlx5_ib_dev *dev, struct mlx5_err_cqe *cqe)
{
        __be32 *p = (__be32 *)cqe;
        int i;

        mlx5_ib_warn(dev, "dump error cqe\n");
        for (i = 0; i < sizeof(*cqe) / 16; i++, p += 4)
                pr_info("%08x %08x %08x %08x\n", be32_to_cpu(p[0]),
                        be32_to_cpu(p[1]), be32_to_cpu(p[2]),
                        be32_to_cpu(p[3]));
}

static void mlx5_handle_error_cqe(struct mlx5_ib_dev *dev,
                                  struct mlx5_err_cqe *cqe,
                                  struct ib_wc *wc)
{
        int dump = 1;

        switch (cqe->syndrome) {
        case MLX5_CQE_SYNDROME_LOCAL_LENGTH_ERR:
                wc->status = IB_WC_LOC_LEN_ERR;
                break;
        case MLX5_CQE_SYNDROME_LOCAL_QP_OP_ERR:
                wc->status = IB_WC_LOC_QP_OP_ERR;
                break;
        case MLX5_CQE_SYNDROME_LOCAL_PROT_ERR:
                wc->status = IB_WC_LOC_PROT_ERR;
                break;
        case MLX5_CQE_SYNDROME_WR_FLUSH_ERR:
                dump = 0;
                wc->status = IB_WC_WR_FLUSH_ERR;
                break;
        case MLX5_CQE_SYNDROME_MW_BIND_ERR:
                wc->status = IB_WC_MW_BIND_ERR;
                break;
        case MLX5_CQE_SYNDROME_BAD_RESP_ERR:
                wc->status = IB_WC_BAD_RESP_ERR;
                break;
        case MLX5_CQE_SYNDROME_LOCAL_ACCESS_ERR:
                wc->status = IB_WC_LOC_ACCESS_ERR;
                break;
        case MLX5_CQE_SYNDROME_REMOTE_INVAL_REQ_ERR:
                wc->status = IB_WC_REM_INV_REQ_ERR;
                break;
        case MLX5_CQE_SYNDROME_REMOTE_ACCESS_ERR:
                wc->status = IB_WC_REM_ACCESS_ERR;
                break;
        case MLX5_CQE_SYNDROME_REMOTE_OP_ERR:
                wc->status = IB_WC_REM_OP_ERR;
                break;
        case MLX5_CQE_SYNDROME_TRANSPORT_RETRY_EXC_ERR:
                wc->status = IB_WC_RETRY_EXC_ERR;
                dump = 0;
                break;
        case MLX5_CQE_SYNDROME_RNR_RETRY_EXC_ERR:
                wc->status = IB_WC_RNR_RETRY_EXC_ERR;
                dump = 0;
                break;
        case MLX5_CQE_SYNDROME_REMOTE_ABORTED_ERR:
                wc->status = IB_WC_REM_ABORT_ERR;
                break;
        default:
                wc->status = IB_WC_GENERAL_ERR;
                break;
        }

        wc->vendor_err = cqe->vendor_err_synd;
        if (dump)
                dump_cqe(dev, cqe);
}

static int is_atomic_response(struct mlx5_ib_qp *qp, uint16_t idx)
{
        /* TBD: waiting decision
        */
        return 0;
}

static void *mlx5_get_atomic_laddr(struct mlx5_ib_qp *qp, uint16_t idx)
{
        struct mlx5_wqe_data_seg *dpseg;
        void *addr;

        dpseg = mlx5_get_send_wqe(qp, idx) + sizeof(struct mlx5_wqe_ctrl_seg) +
                sizeof(struct mlx5_wqe_raddr_seg) +
                sizeof(struct mlx5_wqe_atomic_seg);
        addr = (void *)(unsigned long)be64_to_cpu(dpseg->addr);
        return addr;
}

static void handle_atomic(struct mlx5_ib_qp *qp, struct mlx5_cqe64 *cqe64,
                          uint16_t idx)
{
        void *addr;
        int byte_count;
        int i;

        if (!is_atomic_response(qp, idx))
                return;

        byte_count = be32_to_cpu(cqe64->byte_cnt);
        addr = mlx5_get_atomic_laddr(qp, idx);

        if (byte_count == 4) {
                *(uint32_t *)addr = be32_to_cpu(*((__be32 *)addr));
        } else {
                for (i = 0; i < byte_count; i += 8) {
                        *(uint64_t *)addr = be64_to_cpu(*((__be64 *)addr));
                        addr += 8;
                }
        }

        return;
}

static void handle_atomics(struct mlx5_ib_qp *qp, struct mlx5_cqe64 *cqe64,
                           u16 tail, u16 head)
{
        int idx;

        do {
                idx = tail & (qp->sq.wqe_cnt - 1);
                handle_atomic(qp, cqe64, idx);
                if (idx == head)
                        break;

                tail = qp->sq.w_list[idx].next;
        } while (1);
        tail = qp->sq.w_list[idx].next;
        qp->sq.last_poll = tail;
}

static void free_cq_buf(struct mlx5_ib_dev *dev, struct mlx5_ib_cq_buf *buf)
{
        mlx5_buf_free(&dev->mdev, &buf->buf);
}

static int mlx5_poll_one(struct mlx5_ib_cq *cq,
                         struct mlx5_ib_qp **cur_qp,
                         struct ib_wc *wc)
{
        struct mlx5_ib_dev *dev = to_mdev(cq->ibcq.device);
        struct mlx5_err_cqe *err_cqe;
        struct mlx5_cqe64 *cqe64;
        struct mlx5_core_qp *mqp;
        struct mlx5_ib_wq *wq;
        uint8_t opcode;
        uint32_t qpn;
        u16 wqe_ctr;
        void *cqe;
        int idx;

repoll:
        cqe = next_cqe_sw(cq);
        if (!cqe)
                return -EAGAIN;

        cqe64 = (cq->mcq.cqe_sz == 64) ? cqe : cqe + 64;

        ++cq->mcq.cons_index;

        /* Make sure we read CQ entry contents after we've checked the
         * ownership bit.
         */
        rmb();

        opcode = cqe64->op_own >> 4;
        if (unlikely(opcode == MLX5_CQE_RESIZE_CQ)) {
                if (likely(cq->resize_buf)) {
                        free_cq_buf(dev, &cq->buf);
                        cq->buf = *cq->resize_buf;
                        kfree(cq->resize_buf);
                        cq->resize_buf = NULL;
                        goto repoll;
                } else {
                        mlx5_ib_warn(dev, "unexpected resize cqe\n");
                }
        }

        qpn = ntohl(cqe64->sop_drop_qpn) & 0xffffff;
        if (!*cur_qp || (qpn != (*cur_qp)->ibqp.qp_num)) {
                /* We do not have to take the QP table lock here,
                 * because CQs will be locked while QPs are removed
                 * from the table.
                 */
                mqp = __mlx5_qp_lookup(&dev->mdev, qpn);
                if (unlikely(!mqp)) {
                        mlx5_ib_warn(dev, "CQE@CQ %06x for unknown QPN %6x\n",
                                     cq->mcq.cqn, qpn);
                        return -EINVAL;
                }

                *cur_qp = to_mibqp(mqp);
        }

        wc->qp  = &(*cur_qp)->ibqp;
        switch (opcode) {
        case MLX5_CQE_REQ:
                wq = &(*cur_qp)->sq;
                wqe_ctr = be16_to_cpu(cqe64->wqe_counter);
                idx = wqe_ctr & (wq->wqe_cnt - 1);
                handle_good_req(wc, cqe64, wq, idx);
                handle_atomics(*cur_qp, cqe64, wq->last_poll, idx);
                wc->wr_id = wq->wrid[idx];
                wq->tail = wq->wqe_head[idx] + 1;
                wc->status = IB_WC_SUCCESS;
                break;
        case MLX5_CQE_RESP_WR_IMM:
        case MLX5_CQE_RESP_SEND:
        case MLX5_CQE_RESP_SEND_IMM:
        case MLX5_CQE_RESP_SEND_INV:
                handle_responder(wc, cqe64, *cur_qp);
                wc->status = IB_WC_SUCCESS;
                break;
        case MLX5_CQE_RESIZE_CQ:
                break;
        case MLX5_CQE_REQ_ERR:
        case MLX5_CQE_RESP_ERR:
                err_cqe = (struct mlx5_err_cqe *)cqe64;
                mlx5_handle_error_cqe(dev, err_cqe, wc);
                mlx5_ib_dbg(dev, "%s error cqe on cqn 0x%x:\n",
                            opcode == MLX5_CQE_REQ_ERR ?
                            "Requestor" : "Responder", cq->mcq.cqn);
                mlx5_ib_dbg(dev, "syndrome 0x%x, vendor syndrome 0x%x\n",
                            err_cqe->syndrome, err_cqe->vendor_err_synd);
                if (opcode == MLX5_CQE_REQ_ERR) {
                        wq = &(*cur_qp)->sq;
                        wqe_ctr = be16_to_cpu(cqe64->wqe_counter);
                        idx = wqe_ctr & (wq->wqe_cnt - 1);
                        wc->wr_id = wq->wrid[idx];
                        wq->tail = wq->wqe_head[idx] + 1;
                } else {
                        struct mlx5_ib_srq *srq;

                        if ((*cur_qp)->ibqp.srq) {
                                srq = to_msrq((*cur_qp)->ibqp.srq);
                                wqe_ctr = be16_to_cpu(cqe64->wqe_counter);
                                wc->wr_id = srq->wrid[wqe_ctr];
                                mlx5_ib_free_srq_wqe(srq, wqe_ctr);
                        } else {
                                wq = &(*cur_qp)->rq;
                                wc->wr_id = wq->wrid[wq->tail & (wq->wqe_cnt - 1)];
                                ++wq->tail;
                        }
                }
                break;
        }

        return 0;
}

int mlx5_ib_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc)
{
        struct mlx5_ib_cq *cq = to_mcq(ibcq);
        struct mlx5_ib_qp *cur_qp = NULL;
        unsigned long flags;
        int npolled;
        int err = 0;

        spin_lock_irqsave(&cq->lock, flags);

        for (npolled = 0; npolled < num_entries; npolled++) {
                err = mlx5_poll_one(cq, &cur_qp, wc + npolled);
                if (err)
                        break;
        }

        if (npolled)
                mlx5_cq_set_ci(&cq->mcq);

        spin_unlock_irqrestore(&cq->lock, flags);

        if (err == 0 || err == -EAGAIN)
                return npolled;
        else
                return err;
}

int mlx5_ib_arm_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags flags)
{
        mlx5_cq_arm(&to_mcq(ibcq)->mcq,
                    (flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
                    MLX5_CQ_DB_REQ_NOT_SOL : MLX5_CQ_DB_REQ_NOT,
                    to_mdev(ibcq->device)->mdev.priv.uuari.uars[0].map,
                    MLX5_GET_DOORBELL_LOCK(&to_mdev(ibcq->device)->mdev.priv.cq_uar_lock));

        return 0;
}

static int alloc_cq_buf(struct mlx5_ib_dev *dev, struct mlx5_ib_cq_buf *buf,
                        int nent, int cqe_size)
{
        int err;

        err = mlx5_buf_alloc(&dev->mdev, nent * cqe_size,
                             PAGE_SIZE * 2, &buf->buf);
        if (err)
                return err;

        buf->cqe_size = cqe_size;
        buf->nent = nent;

        return 0;
}

static int create_cq_user(struct mlx5_ib_dev *dev, struct ib_udata *udata,
                          struct ib_ucontext *context, struct mlx5_ib_cq *cq,
                          int entries, struct mlx5_create_cq_mbox_in **cqb,
                          int *cqe_size, int *index, int *inlen)
{
        struct mlx5_ib_create_cq ucmd;
        int page_shift;
        int npages;
        int ncont;
        int err;

        if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd)))
                return -EFAULT;

        if (ucmd.cqe_size != 64 && ucmd.cqe_size != 128)
                return -EINVAL;

        *cqe_size = ucmd.cqe_size;

        cq->buf.umem = ib_umem_get(context, ucmd.buf_addr,
                                   entries * ucmd.cqe_size,
                                   IB_ACCESS_LOCAL_WRITE, 1);
        if (IS_ERR(cq->buf.umem)) {
                err = PTR_ERR(cq->buf.umem);
                return err;
        }

        err = mlx5_ib_db_map_user(to_mucontext(context), ucmd.db_addr,
                                  &cq->db);
        if (err)
                goto err_umem;

        mlx5_ib_cont_pages(cq->buf.umem, ucmd.buf_addr, &npages, &page_shift,
                           &ncont, NULL);
        mlx5_ib_dbg(dev, "addr 0x%llx, size %u, npages %d, page_shift %d, ncont %d\n",
                    ucmd.buf_addr, entries * ucmd.cqe_size, npages, page_shift, ncont);

        *inlen = sizeof(**cqb) + sizeof(*(*cqb)->pas) * ncont;
        *cqb = mlx5_vzalloc(*inlen);
        if (!*cqb) {
                err = -ENOMEM;
                goto err_db;
        }
        mlx5_ib_populate_pas(dev, cq->buf.umem, page_shift, (*cqb)->pas, 0);
        (*cqb)->ctx.log_pg_sz = page_shift - MLX5_ADAPTER_PAGE_SHIFT;

        *index = to_mucontext(context)->uuari.uars[0].index;

        return 0;

err_db:
        mlx5_ib_db_unmap_user(to_mucontext(context), &cq->db);

err_umem:
        ib_umem_release(cq->buf.umem);
        return err;
}

static void destroy_cq_user(struct mlx5_ib_cq *cq, struct ib_ucontext *context)
{
        mlx5_ib_db_unmap_user(to_mucontext(context), &cq->db);
        ib_umem_release(cq->buf.umem);
}

static void init_cq_buf(struct mlx5_ib_cq *cq, struct mlx5_ib_cq_buf *buf)
{
        int i;
        void *cqe;
        struct mlx5_cqe64 *cqe64;

        for (i = 0; i < buf->nent; i++) {
                cqe = get_cqe_from_buf(buf, i, buf->cqe_size);
                cqe64 = buf->cqe_size == 64 ? cqe : cqe + 64;
                cqe64->op_own = MLX5_CQE_INVALID << 4;
        }
}

static int create_cq_kernel(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *cq,
                            int entries, int cqe_size,
                            struct mlx5_create_cq_mbox_in **cqb,
                            int *index, int *inlen)
{
        int err;

        err = mlx5_db_alloc(&dev->mdev, &cq->db);
        if (err)
                return err;

        cq->mcq.set_ci_db  = cq->db.db;
        cq->mcq.arm_db     = cq->db.db + 1;
        *cq->mcq.set_ci_db = 0;
        *cq->mcq.arm_db    = 0;
        cq->mcq.cqe_sz = cqe_size;

        err = alloc_cq_buf(dev, &cq->buf, entries, cqe_size);
        if (err)
                goto err_db;

        init_cq_buf(cq, &cq->buf);

        *inlen = sizeof(**cqb) + sizeof(*(*cqb)->pas) * cq->buf.buf.npages;
        *cqb = mlx5_vzalloc(*inlen);
        if (!*cqb) {
                err = -ENOMEM;
                goto err_buf;
        }
        mlx5_fill_page_array(&cq->buf.buf, (*cqb)->pas);

        (*cqb)->ctx.log_pg_sz = cq->buf.buf.page_shift - MLX5_ADAPTER_PAGE_SHIFT;
        *index = dev->mdev.priv.uuari.uars[0].index;

        return 0;

err_buf:
        free_cq_buf(dev, &cq->buf);

err_db:
        mlx5_db_free(&dev->mdev, &cq->db);
        return err;
}

static void destroy_cq_kernel(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *cq)
{
        free_cq_buf(dev, &cq->buf);
        mlx5_db_free(&dev->mdev, &cq->db);
}

struct ib_cq *mlx5_ib_create_cq(struct ib_device *ibdev, int entries,
                                int vector, struct ib_ucontext *context,
                                struct ib_udata *udata)
{
        struct mlx5_create_cq_mbox_in *cqb = NULL;
        struct mlx5_ib_dev *dev = to_mdev(ibdev);
        struct mlx5_ib_cq *cq;
        int uninitialized_var(index);
        int uninitialized_var(inlen);
        int cqe_size;
        int irqn;
        int eqn;
        int err;

        if (entries < 0)
                return ERR_PTR(-EINVAL);

        entries = roundup_pow_of_two(entries + 1);
        if (entries > dev->mdev.caps.max_cqes)
                return ERR_PTR(-EINVAL);

        cq = kzalloc(sizeof(*cq), GFP_KERNEL);
        if (!cq)
                return ERR_PTR(-ENOMEM);

        cq->ibcq.cqe = entries - 1;
        mutex_init(&cq->resize_mutex);
        spin_lock_init(&cq->lock);
        cq->resize_buf = NULL;
        cq->resize_umem = NULL;

        if (context) {
                err = create_cq_user(dev, udata, context, cq, entries,
                                     &cqb, &cqe_size, &index, &inlen);
                if (err)
                        goto err_create;
        } else {
                /* for now choose 64 bytes till we have a proper interface */
                cqe_size = 64;
                err = create_cq_kernel(dev, cq, entries, cqe_size, &cqb,
                                       &index, &inlen);
                if (err)
                        goto err_create;
        }

        cq->cqe_size = cqe_size;
        cqb->ctx.cqe_sz_flags = cqe_sz_to_mlx_sz(cqe_size) << 5;
        cqb->ctx.log_sz_usr_page = cpu_to_be32((ilog2(entries) << 24) | index);
        err = mlx5_vector2eqn(dev, vector, &eqn, &irqn);
        if (err)
                goto err_cqb;

        cqb->ctx.c_eqn = cpu_to_be16(eqn);
        cqb->ctx.db_record_addr = cpu_to_be64(cq->db.dma);

        err = mlx5_core_create_cq(&dev->mdev, &cq->mcq, cqb, inlen);
        if (err)
                goto err_cqb;

        mlx5_ib_dbg(dev, "cqn 0x%x\n", cq->mcq.cqn);
        cq->mcq.irqn = irqn;
        cq->mcq.comp  = mlx5_ib_cq_comp;
        cq->mcq.event = mlx5_ib_cq_event;

        if (context)
                if (ib_copy_to_udata(udata, &cq->mcq.cqn, sizeof(__u32))) {
                        err = -EFAULT;
                        goto err_cmd;
                }


        mlx5_vfree(cqb);
        return &cq->ibcq;

err_cmd:
        mlx5_core_destroy_cq(&dev->mdev, &cq->mcq);

err_cqb:
        mlx5_vfree(cqb);
        if (context)
                destroy_cq_user(cq, context);
        else
                destroy_cq_kernel(dev, cq);

err_create:
        kfree(cq);

        return ERR_PTR(err);
}


int mlx5_ib_destroy_cq(struct ib_cq *cq)
{
        struct mlx5_ib_dev *dev = to_mdev(cq->device);
        struct mlx5_ib_cq *mcq = to_mcq(cq);
        struct ib_ucontext *context = NULL;

        if (cq->uobject)
                context = cq->uobject->context;

        mlx5_core_destroy_cq(&dev->mdev, &mcq->mcq);
        if (context)
                destroy_cq_user(mcq, context);
        else
                destroy_cq_kernel(dev, mcq);

        kfree(mcq);

        return 0;
}

static int is_equal_rsn(struct mlx5_cqe64 *cqe64, u32 rsn)
{
        return rsn == (ntohl(cqe64->sop_drop_qpn) & 0xffffff);
}

void __mlx5_ib_cq_clean(struct mlx5_ib_cq *cq, u32 rsn, struct mlx5_ib_srq *srq)
{
        struct mlx5_cqe64 *cqe64, *dest64;
        void *cqe, *dest;
        u32 prod_index;
        int nfreed = 0;
        u8 owner_bit;

        if (!cq)
                return;

        /* First we need to find the current producer index, so we
         * know where to start cleaning from.  It doesn't matter if HW
         * adds new entries after this loop -- the QP we're worried
         * about is already in RESET, so the new entries won't come
         * from our QP and therefore don't need to be checked.
         */
        for (prod_index = cq->mcq.cons_index; get_sw_cqe(cq, prod_index); prod_index++)
                if (prod_index == cq->mcq.cons_index + cq->ibcq.cqe)
                        break;

        /* Now sweep backwards through the CQ, removing CQ entries
         * that match our QP by copying older entries on top of them.
         */
        while ((int) --prod_index - (int) cq->mcq.cons_index >= 0) {
                cqe = get_cqe(cq, prod_index & cq->ibcq.cqe);
                cqe64 = (cq->mcq.cqe_sz == 64) ? cqe : cqe + 64;
                if (is_equal_rsn(cqe64, rsn)) {
                        if (srq && (ntohl(cqe64->srqn) & 0xffffff))
                                mlx5_ib_free_srq_wqe(srq, be16_to_cpu(cqe64->wqe_counter));
                        ++nfreed;
                } else if (nfreed) {
                        dest = get_cqe(cq, (prod_index + nfreed) & cq->ibcq.cqe);
                        dest64 = (cq->mcq.cqe_sz == 64) ? dest : dest + 64;
                        owner_bit = dest64->op_own & MLX5_CQE_OWNER_MASK;
                        memcpy(dest, cqe, cq->mcq.cqe_sz);
                        dest64->op_own = owner_bit |
                                (dest64->op_own & ~MLX5_CQE_OWNER_MASK);
                }
        }

        if (nfreed) {
                cq->mcq.cons_index += nfreed;
                /* Make sure update of buffer contents is done before
                 * updating consumer index.
                 */
                wmb();
                mlx5_cq_set_ci(&cq->mcq);
        }
}

void mlx5_ib_cq_clean(struct mlx5_ib_cq *cq, u32 qpn, struct mlx5_ib_srq *srq)
{
        if (!cq)
                return;

        spin_lock_irq(&cq->lock);
        __mlx5_ib_cq_clean(cq, qpn, srq);
        spin_unlock_irq(&cq->lock);
}

int mlx5_ib_modify_cq(struct ib_cq *cq, u16 cq_count, u16 cq_period)
{
        struct mlx5_modify_cq_mbox_in *in;
        struct mlx5_ib_dev *dev = to_mdev(cq->device);
        struct mlx5_ib_cq *mcq = to_mcq(cq);
        int err;
        u32 fsel;

        if (!(dev->mdev.caps.flags & MLX5_DEV_CAP_FLAG_CQ_MODER))
                return -ENOSYS;

        in = kzalloc(sizeof(*in), GFP_KERNEL);
        if (!in)
                return -ENOMEM;

        in->cqn = cpu_to_be32(mcq->mcq.cqn);
        fsel = (MLX5_CQ_MODIFY_PERIOD | MLX5_CQ_MODIFY_COUNT);
        in->ctx.cq_period = cpu_to_be16(cq_period);
        in->ctx.cq_max_count = cpu_to_be16(cq_count);
        in->field_select = cpu_to_be32(fsel);
        err = mlx5_core_modify_cq(&dev->mdev, &mcq->mcq, in, sizeof(*in));
        kfree(in);

        if (err)
                mlx5_ib_warn(dev, "modify cq 0x%x failed\n", mcq->mcq.cqn);

        return err;
}

static int resize_user(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *cq,
                       int entries, struct ib_udata *udata, int *npas,
                       int *page_shift, int *cqe_size)
{
        struct mlx5_ib_resize_cq ucmd;
        struct ib_umem *umem;
        int err;
        int npages;
        struct ib_ucontext *context = cq->buf.umem->context;

        err = ib_copy_from_udata(&ucmd, udata, sizeof(ucmd));
        if (err)
                return err;

        if (ucmd.reserved0 || ucmd.reserved1)
                return -EINVAL;

        umem = ib_umem_get(context, ucmd.buf_addr, entries * ucmd.cqe_size,
                           IB_ACCESS_LOCAL_WRITE, 1);
        if (IS_ERR(umem)) {
                err = PTR_ERR(umem);
                return err;
        }

        mlx5_ib_cont_pages(umem, ucmd.buf_addr, &npages, page_shift,
                           npas, NULL);

        cq->resize_umem = umem;
        *cqe_size = ucmd.cqe_size;

        return 0;
}

static void un_resize_user(struct mlx5_ib_cq *cq)
{
        ib_umem_release(cq->resize_umem);
}

static int resize_kernel(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *cq,
                         int entries, int cqe_size)
{
        int err;

        cq->resize_buf = kzalloc(sizeof(*cq->resize_buf), GFP_KERNEL);
        if (!cq->resize_buf)
                return -ENOMEM;

        err = alloc_cq_buf(dev, cq->resize_buf, entries, cqe_size);
        if (err)
                goto ex;

        init_cq_buf(cq, cq->resize_buf);

        return 0;

ex:
        kfree(cq->resize_buf);
        return err;
}

static void un_resize_kernel(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *cq)
{
        free_cq_buf(dev, cq->resize_buf);
        cq->resize_buf = NULL;
}

static int copy_resize_cqes(struct mlx5_ib_cq *cq)
{
        struct mlx5_ib_dev *dev = to_mdev(cq->ibcq.device);
        struct mlx5_cqe64 *scqe64;
        struct mlx5_cqe64 *dcqe64;
        void *start_cqe;
        void *scqe;
        void *dcqe;
        int ssize;
        int dsize;
        int i;
        u8 sw_own;

        ssize = cq->buf.cqe_size;
        dsize = cq->resize_buf->cqe_size;
        if (ssize != dsize) {
                mlx5_ib_warn(dev, "resize from different cqe size is not supported\n");
                return -EINVAL;
        }

        i = cq->mcq.cons_index;
        scqe = get_sw_cqe(cq, i);
        scqe64 = ssize == 64 ? scqe : scqe + 64;
        start_cqe = scqe;
        if (!scqe) {
                mlx5_ib_warn(dev, "expected cqe in sw ownership\n");
                return -EINVAL;
        }

        while ((scqe64->op_own >> 4) != MLX5_CQE_RESIZE_CQ) {
                dcqe = get_cqe_from_buf(cq->resize_buf,
                                        (i + 1) & (cq->resize_buf->nent),
                                        dsize);
                dcqe64 = dsize == 64 ? dcqe : dcqe + 64;
                sw_own = sw_ownership_bit(i + 1, cq->resize_buf->nent);
                memcpy(dcqe, scqe, dsize);
                dcqe64->op_own = (dcqe64->op_own & ~MLX5_CQE_OWNER_MASK) | sw_own;

                ++i;
                scqe = get_sw_cqe(cq, i);
                scqe64 = ssize == 64 ? scqe : scqe + 64;
                if (!scqe) {
                        mlx5_ib_warn(dev, "expected cqe in sw ownership\n");
                        return -EINVAL;
                }

                if (scqe == start_cqe) {
                        pr_warn("resize CQ failed to get resize CQE, CQN 0x%x\n",
                                cq->mcq.cqn);
                        return -ENOMEM;
                }
        }
        ++cq->mcq.cons_index;
        return 0;
}

int mlx5_ib_resize_cq(struct ib_cq *ibcq, int entries, struct ib_udata *udata)
{
        struct mlx5_ib_dev *dev = to_mdev(ibcq->device);
        struct mlx5_ib_cq *cq = to_mcq(ibcq);
        struct mlx5_modify_cq_mbox_in *in;
        int err;
        int npas;
        int page_shift;
        int inlen;
        int uninitialized_var(cqe_size);
        unsigned long flags;

        if (!(dev->mdev.caps.flags & MLX5_DEV_CAP_FLAG_RESIZE_CQ)) {
                pr_info("Firmware does not support resize CQ\n");
                return -ENOSYS;
        }

        if (entries < 1)
                return -EINVAL;

        entries = roundup_pow_of_two(entries + 1);
        if (entries > dev->mdev.caps.max_cqes + 1)
                return -EINVAL;

        if (entries == ibcq->cqe + 1)
                return 0;

        mutex_lock(&cq->resize_mutex);
        if (udata) {
                err = resize_user(dev, cq, entries, udata, &npas, &page_shift,
                                  &cqe_size);
        } else {
                cqe_size = 64;
                err = resize_kernel(dev, cq, entries, cqe_size);
                if (!err) {
                        npas = cq->resize_buf->buf.npages;
                        page_shift = cq->resize_buf->buf.page_shift;
                }
        }

        if (err)
                goto ex;

        inlen = sizeof(*in) + npas * sizeof(in->pas[0]);
        in = mlx5_vzalloc(inlen);
        if (!in) {
                err = -ENOMEM;
                goto ex_resize;
        }

        if (udata)
                mlx5_ib_populate_pas(dev, cq->resize_umem, page_shift,
                                     in->pas, 0);
        else
                mlx5_fill_page_array(&cq->resize_buf->buf, in->pas);

        in->field_select = cpu_to_be32(MLX5_MODIFY_CQ_MASK_LOG_SIZE  |
                                       MLX5_MODIFY_CQ_MASK_PG_OFFSET |
                                       MLX5_MODIFY_CQ_MASK_PG_SIZE);
        in->ctx.log_pg_sz = page_shift - MLX5_ADAPTER_PAGE_SHIFT;
        in->ctx.cqe_sz_flags = cqe_sz_to_mlx_sz(cqe_size) << 5;
        in->ctx.page_offset = 0;
        in->ctx.log_sz_usr_page = cpu_to_be32(ilog2(entries) << 24);
        in->hdr.opmod = cpu_to_be16(MLX5_CQ_OPMOD_RESIZE);
        in->cqn = cpu_to_be32(cq->mcq.cqn);

        err = mlx5_core_modify_cq(&dev->mdev, &cq->mcq, in, inlen);
        if (err)
                goto ex_alloc;

        if (udata) {
                cq->ibcq.cqe = entries - 1;
                ib_umem_release(cq->buf.umem);
                cq->buf.umem = cq->resize_umem;
                cq->resize_umem = NULL;
        } else {
                struct mlx5_ib_cq_buf tbuf;
                int resized = 0;

                spin_lock_irqsave(&cq->lock, flags);
                if (cq->resize_buf) {
                        err = copy_resize_cqes(cq);
                        if (!err) {
                                tbuf = cq->buf;
                                cq->buf = *cq->resize_buf;
                                kfree(cq->resize_buf);
                                cq->resize_buf = NULL;
                                resized = 1;
                        }
                }
                cq->ibcq.cqe = entries - 1;
                spin_unlock_irqrestore(&cq->lock, flags);
                if (resized)
                        free_cq_buf(dev, &tbuf);
        }
        mutex_unlock(&cq->resize_mutex);

        mlx5_vfree(in);
        return 0;

ex_alloc:
        mlx5_vfree(in);

ex_resize:
        if (udata)
                un_resize_user(cq);
        else
                un_resize_kernel(dev, cq);
ex:
        mutex_unlock(&cq->resize_mutex);
        return err;
}

int mlx5_ib_get_cqe_size(struct mlx5_ib_dev *dev, struct ib_cq *ibcq)
{
        struct mlx5_ib_cq *cq;

        if (!ibcq)
                return 128;

        cq = to_mcq(ibcq);
        return cq->cqe_size;
}