5255 uts shouldn't open-code ISP2

[illumos-gate.git] / usr / src / uts / common / io / ib / adapters / tavor / tavor_qp.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * tavor_qp.c
 *    Tavor Queue Pair Processing Routines
 *
 *    Implements all the routines necessary for allocating, freeing, and
 *    querying the Tavor queue pairs.
 */

#include <sys/types.h>
#include <sys/conf.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/modctl.h>
#include <sys/bitmap.h>
#include <sys/sysmacros.h>

#include <sys/ib/adapters/tavor/tavor.h>
#include <sys/ib/ib_pkt_hdrs.h>

static int tavor_qp_create_qpn(tavor_state_t *state, tavor_qphdl_t qp,
    tavor_rsrc_t *qpc);
static int tavor_qpn_avl_compare(const void *q, const void *e);
static int tavor_special_qp_rsrc_alloc(tavor_state_t *state,
    ibt_sqp_type_t type, uint_t port, tavor_rsrc_t **qp_rsrc);
static int tavor_special_qp_rsrc_free(tavor_state_t *state, ibt_sqp_type_t type,
    uint_t port);
static void tavor_qp_sgl_to_logwqesz(tavor_state_t *state, uint_t num_sgl,
    tavor_qp_wq_type_t wq_type, uint_t *logwqesz, uint_t *max_sgl);

/*
 * tavor_qp_alloc()
 *    Context: Can be called only from user or kernel context.
 */
int
tavor_qp_alloc(tavor_state_t *state, tavor_qp_info_t *qpinfo,
    uint_t sleepflag, tavor_qp_options_t *op)
{
        tavor_rsrc_pool_info_t  *rsrc_pool;
        tavor_rsrc_t            *qpc, *rsrc, *rdb;
        tavor_umap_db_entry_t   *umapdb;
        tavor_qphdl_t           qp;
        ibt_qp_alloc_attr_t     *attr_p;
        ibt_qp_type_t           type;
        ibtl_qp_hdl_t           ibt_qphdl;
        ibt_chan_sizes_t        *queuesz_p;
        ib_qpn_t                *qpn;
        tavor_qphdl_t           *qphdl;
        ibt_mr_attr_t           mr_attr;
        tavor_mr_options_t      mr_op;
        tavor_srqhdl_t          srq;
        tavor_pdhdl_t           pd;
        tavor_cqhdl_t           sq_cq, rq_cq;
        tavor_mrhdl_t           mr;
        uint64_t                value, qp_desc_off;
        uint32_t                *sq_buf, *rq_buf;
        uint32_t                log_qp_sq_size, log_qp_rq_size;
        uint32_t                sq_size, rq_size;
        uint32_t                sq_wqe_size, rq_wqe_size;
        uint32_t                max_rdb, max_sgl, uarpg;
        uint_t                  wq_location, dma_xfer_mode, qp_is_umap;
        uint_t                  qp_srq_en;
        int                     status, flag;
        char                    *errormsg;

        TAVOR_TNF_ENTER(tavor_qp_alloc);

        _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*attr_p, *queuesz_p))

        /*
         * Check the "options" flag.  Currently this flag tells the driver
         * whether or not the QP's work queues should be come from normal
         * system memory or whether they should be allocated from DDR memory.
         */
        if (op == NULL) {
                wq_location = TAVOR_QUEUE_LOCATION_NORMAL;
        } else {
                wq_location = op->qpo_wq_loc;
        }

        /*
         * Extract the necessary info from the tavor_qp_info_t structure
         */
        attr_p    = qpinfo->qpi_attrp;
        type      = qpinfo->qpi_type;
        ibt_qphdl = qpinfo->qpi_ibt_qphdl;
        queuesz_p = qpinfo->qpi_queueszp;
        qpn       = qpinfo->qpi_qpn;
        qphdl     = &qpinfo->qpi_qphdl;

        /*
         * Determine whether QP is being allocated for userland access or
         * whether it is being allocated for kernel access.  If the QP is
         * being allocated for userland access, then lookup the UAR doorbell
         * page number for the current process.  Note:  If this is not found
         * (e.g. if the process has not previously open()'d the Tavor driver),
         * then an error is returned.
         */
        qp_is_umap = (attr_p->qp_alloc_flags & IBT_QP_USER_MAP) ? 1 : 0;
        if (qp_is_umap) {
                status = tavor_umap_db_find(state->ts_instance, ddi_get_pid(),
                    MLNX_UMAP_UARPG_RSRC, &value, 0, NULL);
                if (status != DDI_SUCCESS) {
                        /* Set "status" and "errormsg" and goto failure */
                        TAVOR_TNF_FAIL(IBT_INVALID_PARAM, "failed UAR page");
                        goto qpalloc_fail;
                }
                uarpg = ((tavor_rsrc_t *)(uintptr_t)value)->tr_indx;
        }

        /*
         * Determine whether QP is being associated with an SRQ
         */
        qp_srq_en = (attr_p->qp_alloc_flags & IBT_QP_USES_SRQ) ? 1 : 0;
        if (qp_srq_en) {
                /*
                 * Check for valid SRQ handle pointers
                 */
                if (attr_p->qp_ibc_srq_hdl == NULL) {
                        /* Set "status" and "errormsg" and goto failure */
                        TAVOR_TNF_FAIL(IBT_SRQ_HDL_INVALID,
                            "invalid SRQ handle");
                        goto qpalloc_fail;
                }
                srq = (tavor_srqhdl_t)attr_p->qp_ibc_srq_hdl;
        }

        /*
         * Check for valid QP service type (only UD/RC/UC supported)
         */
        if (((type != IBT_UD_RQP) && (type != IBT_RC_RQP) &&
            (type != IBT_UC_RQP))) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_QP_SRV_TYPE_INVALID, "invalid serv type");
                goto qpalloc_fail;
        }

        /*
         * Only RC is supported on an SRQ -- This is a Tavor hardware
         * limitation.  Arbel native mode will not have this shortcoming.
         */
        if (qp_srq_en && type != IBT_RC_RQP) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INVALID_PARAM, "invalid serv type with SRQ");
                goto qpalloc_fail;
        }

        /*
         * Check for valid PD handle pointer
         */
        if (attr_p->qp_pd_hdl == NULL) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_PD_HDL_INVALID, "invalid PD handle");
                goto qpalloc_fail;
        }
        pd = (tavor_pdhdl_t)attr_p->qp_pd_hdl;

        /*
         * If on an SRQ, check to make sure the PD is the same
         */
        if (qp_srq_en && (pd->pd_pdnum != srq->srq_pdhdl->pd_pdnum)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_PD_HDL_INVALID, "invalid PD handle");
                goto qpalloc_fail;
        }

        /* Increment the reference count on the protection domain (PD) */
        tavor_pd_refcnt_inc(pd);

        /*
         * Check for valid CQ handle pointers
         */
        if ((attr_p->qp_ibc_scq_hdl == NULL) ||
            (attr_p->qp_ibc_rcq_hdl == NULL)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_CQ_HDL_INVALID, "invalid CQ handle");
                goto qpalloc_fail1;
        }
        sq_cq = (tavor_cqhdl_t)attr_p->qp_ibc_scq_hdl;
        rq_cq = (tavor_cqhdl_t)attr_p->qp_ibc_rcq_hdl;

        /*
         * Increment the reference count on the CQs.  One or both of these
         * could return error if we determine that the given CQ is already
         * being used with a special (SMI/GSI) QP.
         */
        status = tavor_cq_refcnt_inc(sq_cq, TAVOR_CQ_IS_NORMAL);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_CQ_HDL_INVALID, "invalid CQ handle");
                goto qpalloc_fail1;
        }
        status = tavor_cq_refcnt_inc(rq_cq, TAVOR_CQ_IS_NORMAL);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_CQ_HDL_INVALID, "invalid CQ handle");
                goto qpalloc_fail2;
        }

        /*
         * Allocate an QP context entry.  This will be filled in with all
         * the necessary parameters to define the Queue Pair.  Unlike
         * other Tavor hardware resources, ownership is not immediately
         * given to hardware in the final step here.  Instead, we must
         * wait until the QP is later transitioned to the "Init" state before
         * passing the QP to hardware.  If we fail here, we must undo all
         * the reference count (CQ and PD).
         */
        status = tavor_rsrc_alloc(state, TAVOR_QPC, 1, sleepflag, &qpc);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed QP context");
                goto qpalloc_fail3;
        }

        /*
         * Allocate the software structure for tracking the queue pair
         * (i.e. the Tavor Queue Pair handle).  If we fail here, we must
         * undo the reference counts and the previous resource allocation.
         */
        status = tavor_rsrc_alloc(state, TAVOR_QPHDL, 1, sleepflag, &rsrc);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed QP handle");
                goto qpalloc_fail4;
        }
        qp = (tavor_qphdl_t)rsrc->tr_addr;
        _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*qp))

        /*
         * Calculate the QP number from QPC index.  This routine handles
         * all of the operations necessary to keep track of used, unused,
         * and released QP numbers.
         */
        status = tavor_qp_create_qpn(state, qp, qpc);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed QPN create");
                goto qpalloc_fail5;
        }

        /*
         * If this will be a user-mappable QP, then allocate an entry for
         * the "userland resources database".  This will later be added to
         * the database (after all further QP operations are successful).
         * If we fail here, we must undo the reference counts and the
         * previous resource allocation.
         */
        if (qp_is_umap) {
                umapdb = tavor_umap_db_alloc(state->ts_instance, qp->qp_qpnum,
                    MLNX_UMAP_QPMEM_RSRC, (uint64_t)(uintptr_t)rsrc);
                if (umapdb == NULL) {
                        /* Set "status" and "errormsg" and goto failure */
                        TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed umap add");
                        goto qpalloc_fail6;
                }
        }

        /*
         * If this is an RC QP, then pre-allocate the maximum number of RDB
         * entries.  This allows us to ensure that we can later cover all
         * the resources needed by hardware for handling multiple incoming
         * RDMA Reads.  Note: These resources are obviously not always
         * necessary.  They are allocated here anyway.  Someday maybe this
         * can be modified to allocate these on-the-fly (i.e. only if RDMA
         * Read or Atomic operations are enabled) XXX
         * If we fail here, we have a bunch of resource and reference count
         * cleanup to do.
         */
        if (type == IBT_RC_RQP) {
                max_rdb = state->ts_cfg_profile->cp_hca_max_rdma_in_qp;
                status = tavor_rsrc_alloc(state, TAVOR_RDB, max_rdb,
                    sleepflag, &rdb);
                if (status != DDI_SUCCESS) {
                        /* Set "status" and "errormsg" and goto failure */
                        TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed RDB");
                        goto qpalloc_fail7;
                }
                qp->qp_rdbrsrcp = rdb;
                /* Calculate offset (into DDR memory) of RDB entries */
                rsrc_pool = &state->ts_rsrc_hdl[TAVOR_RDB];
                qp->qp_rdb_ddraddr = (uintptr_t)rsrc_pool->rsrc_ddr_offset +
                    (rdb->tr_indx << TAVOR_RDB_SIZE_SHIFT);
        }

        /*
         * Calculate the appropriate size for the work queues.
         * Note:  All Tavor QP work queues must be a power-of-2 in size.  Also
         * they may not be any smaller than TAVOR_QP_MIN_SIZE.  This step is
         * to round the requested size up to the next highest power-of-2
         */
        attr_p->qp_sizes.cs_sq = max(attr_p->qp_sizes.cs_sq, TAVOR_QP_MIN_SIZE);
        attr_p->qp_sizes.cs_rq = max(attr_p->qp_sizes.cs_rq, TAVOR_QP_MIN_SIZE);
        log_qp_sq_size = highbit(attr_p->qp_sizes.cs_sq);
        if (ISP2(attr_p->qp_sizes.cs_sq)) {
                log_qp_sq_size = log_qp_sq_size - 1;
        }
        log_qp_rq_size = highbit(attr_p->qp_sizes.cs_rq);
        if (ISP2(attr_p->qp_sizes.cs_rq)) {
                log_qp_rq_size = log_qp_rq_size - 1;
        }

        /*
         * Next we verify that the rounded-up size is valid (i.e. consistent
         * with the device limits and/or software-configured limits).  If not,
         * then obviously we have a lot of cleanup to do before returning.
         */
        if ((log_qp_sq_size > state->ts_cfg_profile->cp_log_max_qp_sz) ||
            (!qp_srq_en && (log_qp_rq_size >
            state->ts_cfg_profile->cp_log_max_qp_sz))) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_HCA_WR_EXCEEDED, "max QP size");
                goto qpalloc_fail8;
        }

        /*
         * Next we verify that the requested number of SGL is valid (i.e.
         * consistent with the device limits and/or software-configured
         * limits).  If not, then obviously the same cleanup needs to be done.
         */
        max_sgl = state->ts_cfg_profile->cp_wqe_real_max_sgl;
        if ((attr_p->qp_sizes.cs_sq_sgl > max_sgl) ||
            (!qp_srq_en && (attr_p->qp_sizes.cs_rq_sgl > max_sgl))) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_HCA_SGL_EXCEEDED, "max QP SGL");
                goto qpalloc_fail8;
        }

        /*
         * Determine this QP's WQE sizes (for both the Send and Recv WQEs).
         * This will depend on the requested number of SGLs.  Note: this
         * has the side-effect of also calculating the real number of SGLs
         * (for the calculated WQE size).
         *
         * For QP's on an SRQ, we set these to 0.
         */
        if (qp_srq_en) {
                qp->qp_rq_log_wqesz = 0;
                qp->qp_rq_sgl = 0;
        } else {
                tavor_qp_sgl_to_logwqesz(state, attr_p->qp_sizes.cs_rq_sgl,
                    TAVOR_QP_WQ_TYPE_RECVQ, &qp->qp_rq_log_wqesz,
                    &qp->qp_rq_sgl);
        }
        tavor_qp_sgl_to_logwqesz(state, attr_p->qp_sizes.cs_sq_sgl,
            TAVOR_QP_WQ_TYPE_SENDQ, &qp->qp_sq_log_wqesz, &qp->qp_sq_sgl);

        /*
         * Allocate the memory for QP work queues.  Note:  The location from
         * which we will allocate these work queues has been passed in
         * through the tavor_qp_options_t structure.  Since Tavor work queues
         * are not allowed to cross a 32-bit (4GB) boundary, the alignment of
         * the work queue memory is very important.  We used to allocate
         * work queues (the combined receive and send queues) so that they
         * would be aligned on their combined size.  That alignment guaranteed
         * that they would never cross the 4GB boundary (Tavor work queues
         * are on the order of MBs at maximum).  Now we are able to relax
         * this alignment constraint by ensuring that the IB address assigned
         * to the queue memory (as a result of the tavor_mr_register() call)
         * is offset from zero.
         * Previously, we had wanted to use the ddi_dma_mem_alloc() routine to
         * guarantee the alignment, but when attempting to use IOMMU bypass
         * mode we found that we were not allowed to specify any alignment
         * that was more restrictive than the system page size.
         * So we avoided this constraint by passing two alignment values,
         * one for the memory allocation itself and the other for the DMA
         * handle (for later bind).  This used to cause more memory than
         * necessary to be allocated (in order to guarantee the more
         * restrictive alignment contraint).  But be guaranteeing the
         * zero-based IB virtual address for the queue, we are able to
         * conserve this memory.
         * Note: If QP is not user-mappable, then it may come from either
         * kernel system memory or from HCA-attached local DDR memory.
         */
        sq_wqe_size = 1 << qp->qp_sq_log_wqesz;
        sq_size     = (1 << log_qp_sq_size) * sq_wqe_size;

        /* QP on SRQ sets these to 0 */
        if (qp_srq_en) {
                rq_wqe_size = 0;
                rq_size     = 0;
        } else {
                rq_wqe_size = 1 << qp->qp_rq_log_wqesz;
                rq_size     = (1 << log_qp_rq_size) * rq_wqe_size;
        }

        qp->qp_wqinfo.qa_size = sq_size + rq_size;
        qp->qp_wqinfo.qa_alloc_align = max(sq_wqe_size, rq_wqe_size);
        qp->qp_wqinfo.qa_bind_align  = max(sq_wqe_size, rq_wqe_size);
        if (qp_is_umap) {
                qp->qp_wqinfo.qa_location = TAVOR_QUEUE_LOCATION_USERLAND;
        } else {
                qp->qp_wqinfo.qa_location = wq_location;
        }
        status = tavor_queue_alloc(state, &qp->qp_wqinfo, sleepflag);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed work queue");
                goto qpalloc_fail8;
        }
        if (sq_wqe_size > rq_wqe_size) {
                sq_buf = qp->qp_wqinfo.qa_buf_aligned;

                /*
                 * If QP's on an SRQ, we set the rq_buf to NULL
                 */
                if (qp_srq_en)
                        rq_buf = NULL;
                else
                        rq_buf = (uint32_t *)((uintptr_t)sq_buf + sq_size);
        } else {
                rq_buf = qp->qp_wqinfo.qa_buf_aligned;
                sq_buf = (uint32_t *)((uintptr_t)rq_buf + rq_size);
        }

        /*
         * Register the memory for the QP work queues.  The memory for the
         * QP must be registered in the Tavor TPT tables.  This gives us the
         * LKey to specify in the QP context later.  Note: The memory for
         * Tavor work queues (both Send and Recv) must be contiguous and
         * registered as a single memory region.  Note also: If the work
         * queue is to be allocated from DDR memory, then only a "bypass"
         * mapping is appropriate.  And if the QP memory is user-mappable,
         * then we force DDI_DMA_CONSISTENT mapping.
         * Also, in order to meet the alignment restriction, we pass the
         * "mro_bind_override_addr" flag in the call to tavor_mr_register().
         * This guarantees that the resulting IB vaddr will be zero-based
         * (modulo the offset into the first page).
         * If we fail here, we still have the bunch of resource and reference
         * count cleanup to do.
         */
        flag = (sleepflag == TAVOR_SLEEP) ? IBT_MR_SLEEP :
            IBT_MR_NOSLEEP;
        mr_attr.mr_vaddr    = (uint64_t)(uintptr_t)qp->qp_wqinfo.qa_buf_aligned;
        mr_attr.mr_len      = qp->qp_wqinfo.qa_size;
        mr_attr.mr_as       = NULL;
        mr_attr.mr_flags    = flag;
        if (qp_is_umap) {
                mr_op.mro_bind_type = state->ts_cfg_profile->cp_iommu_bypass;
        } else {
                if (wq_location == TAVOR_QUEUE_LOCATION_NORMAL) {
                        mr_op.mro_bind_type =
                            state->ts_cfg_profile->cp_iommu_bypass;
                        dma_xfer_mode =
                            state->ts_cfg_profile->cp_streaming_consistent;
                        if (dma_xfer_mode == DDI_DMA_STREAMING) {
                                mr_attr.mr_flags |= IBT_MR_NONCOHERENT;
                        }
                } else {
                        mr_op.mro_bind_type = TAVOR_BINDMEM_BYPASS;
                }
        }
        mr_op.mro_bind_dmahdl = qp->qp_wqinfo.qa_dmahdl;
        mr_op.mro_bind_override_addr = 1;
        status = tavor_mr_register(state, pd, &mr_attr, &mr, &mr_op);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed register mr");
                goto qpalloc_fail9;
        }

        /*
         * Calculate the offset between the kernel virtual address space
         * and the IB virtual address space.  This will be used when
         * posting work requests to properly initialize each WQE.
         */
        qp_desc_off = (uint64_t)(uintptr_t)qp->qp_wqinfo.qa_buf_aligned -
            (uint64_t)mr->mr_bindinfo.bi_addr;

        /*
         * Fill in all the return arguments (if necessary).  This includes
         * real work queue sizes, real SGLs, and QP number
         */
        if (queuesz_p != NULL) {
                queuesz_p->cs_sq        = (1 << log_qp_sq_size);
                queuesz_p->cs_sq_sgl    = qp->qp_sq_sgl;

                /* QP on an SRQ set these to 0 */
                if (qp_srq_en) {
                        queuesz_p->cs_rq        = 0;
                        queuesz_p->cs_rq_sgl    = 0;
                } else {
                        queuesz_p->cs_rq        = (1 << log_qp_rq_size);
                        queuesz_p->cs_rq_sgl    = qp->qp_rq_sgl;
                }
        }
        if (qpn != NULL) {
                *qpn = (ib_qpn_t)qp->qp_qpnum;
        }

        /*
         * Fill in the rest of the Tavor Queue Pair handle.  We can update
         * the following fields for use in further operations on the QP.
         */
        qp->qp_qpcrsrcp         = qpc;
        qp->qp_rsrcp            = rsrc;
        qp->qp_state            = TAVOR_QP_RESET;
        qp->qp_pdhdl            = pd;
        qp->qp_mrhdl            = mr;
        qp->qp_sq_sigtype       = (attr_p->qp_flags & IBT_WR_SIGNALED) ?
            TAVOR_QP_SQ_WR_SIGNALED : TAVOR_QP_SQ_ALL_SIGNALED;
        qp->qp_is_special       = 0;
        qp->qp_is_umap          = qp_is_umap;
        qp->qp_uarpg            = (qp->qp_is_umap) ? uarpg : 0;
        qp->qp_umap_dhp         = (devmap_cookie_t)NULL;
        qp->qp_sq_cqhdl         = sq_cq;
        qp->qp_sq_lastwqeaddr   = NULL;
        qp->qp_sq_bufsz         = (1 << log_qp_sq_size);
        qp->qp_sq_buf           = sq_buf;
        qp->qp_desc_off         = qp_desc_off;
        qp->qp_rq_cqhdl         = rq_cq;
        qp->qp_rq_lastwqeaddr   = NULL;
        qp->qp_rq_buf           = rq_buf;

        /* QP on an SRQ sets this to 0 */
        if (qp_srq_en) {
                qp->qp_rq_bufsz         = 0;
        } else {
                qp->qp_rq_bufsz         = (1 << log_qp_rq_size);
        }

        qp->qp_forward_sqd_event  = 0;
        qp->qp_sqd_still_draining = 0;
        qp->qp_hdlrarg          = (void *)ibt_qphdl;
        qp->qp_mcg_refcnt       = 0;

        /*
         * If this QP is to be associated with an SRQ, then set the SRQ handle
         * appropriately.
         */
        if (qp_srq_en) {
                qp->qp_srqhdl = srq;
                qp->qp_srq_en = TAVOR_QP_SRQ_ENABLED;
                tavor_srq_refcnt_inc(qp->qp_srqhdl);
        } else {
                qp->qp_srqhdl = NULL;
                qp->qp_srq_en = TAVOR_QP_SRQ_DISABLED;
        }

        /* Determine if later ddi_dma_sync will be necessary */
        qp->qp_sync = TAVOR_QP_IS_SYNC_REQ(state, qp->qp_wqinfo);

        /* Determine the QP service type */
        if (type == IBT_RC_RQP) {
                qp->qp_serv_type = TAVOR_QP_RC;
        } else if (type == IBT_UD_RQP) {
                qp->qp_serv_type = TAVOR_QP_UD;
        } else {
                qp->qp_serv_type = TAVOR_QP_UC;
        }

        /* Zero out the QP context */
        bzero(&qp->qpc, sizeof (tavor_hw_qpc_t));

        /*
         * Put QP handle in Tavor QPNum-to-QPHdl list.  Then fill in the
         * "qphdl" and return success
         */
        ASSERT(state->ts_qphdl[qpc->tr_indx] == NULL);
        state->ts_qphdl[qpc->tr_indx] = qp;

        /*
         * If this is a user-mappable QP, then we need to insert the previously
         * allocated entry into the "userland resources database".  This will
         * allow for later lookup during devmap() (i.e. mmap()) calls.
         */
        if (qp_is_umap) {
                tavor_umap_db_add(umapdb);
        }

        *qphdl = qp;

        TAVOR_TNF_EXIT(tavor_qp_alloc);
        return (DDI_SUCCESS);

/*
 * The following is cleanup for all possible failure cases in this routine
 */
qpalloc_fail9:
        tavor_queue_free(state, &qp->qp_wqinfo);
qpalloc_fail8:
        if (type == IBT_RC_RQP) {
                tavor_rsrc_free(state, &rdb);
        }
qpalloc_fail7:
        if (qp_is_umap) {
                tavor_umap_db_free(umapdb);
        }
qpalloc_fail6:
        /*
         * Releasing the QPN will also free up the QPC context.  Update
         * the QPC context pointer to indicate this.
         */
        tavor_qp_release_qpn(state, qp->qp_qpn_hdl, TAVOR_QPN_RELEASE);
        qpc = NULL;
qpalloc_fail5:
        tavor_rsrc_free(state, &rsrc);
qpalloc_fail4:
        if (qpc) {
                tavor_rsrc_free(state, &qpc);
        }
qpalloc_fail3:
        tavor_cq_refcnt_dec(rq_cq);
qpalloc_fail2:
        tavor_cq_refcnt_dec(sq_cq);
qpalloc_fail1:
        tavor_pd_refcnt_dec(pd);
qpalloc_fail:
        TNF_PROBE_1(tavor_qp_alloc_fail, TAVOR_TNF_ERROR, "",
            tnf_string, msg, errormsg);
        TAVOR_TNF_EXIT(tavor_qp_alloc);
        return (status);
}



/*
 * tavor_special_qp_alloc()
 *    Context: Can be called only from user or kernel context.
 */
int
tavor_special_qp_alloc(tavor_state_t *state, tavor_qp_info_t *qpinfo,
    uint_t sleepflag, tavor_qp_options_t *op)
{
        tavor_rsrc_t            *qpc, *rsrc;
        tavor_qphdl_t           qp;
        ibt_qp_alloc_attr_t     *attr_p;
        ibt_sqp_type_t          type;
        uint8_t                 port;
        ibtl_qp_hdl_t           ibt_qphdl;
        ibt_chan_sizes_t        *queuesz_p;
        tavor_qphdl_t           *qphdl;
        ibt_mr_attr_t           mr_attr;
        tavor_mr_options_t      mr_op;
        tavor_pdhdl_t           pd;
        tavor_cqhdl_t           sq_cq, rq_cq;
        tavor_mrhdl_t           mr;
        uint64_t                qp_desc_off;
        uint32_t                *sq_buf, *rq_buf;
        uint32_t                log_qp_sq_size, log_qp_rq_size;
        uint32_t                sq_size, rq_size, max_sgl;
        uint32_t                sq_wqe_size, rq_wqe_size;
        uint_t                  wq_location, dma_xfer_mode;
        int                     status, flag;
        char                    *errormsg;

        TAVOR_TNF_ENTER(tavor_special_qp_alloc);

        /*
         * Check the "options" flag.  Currently this flag tells the driver
         * whether or not the QP's work queues should be come from normal
         * system memory or whether they should be allocated from DDR memory.
         */
        if (op == NULL) {
                wq_location = TAVOR_QUEUE_LOCATION_NORMAL;
        } else {
                wq_location = op->qpo_wq_loc;
        }

        /*
         * Extract the necessary info from the tavor_qp_info_t structure
         */
        attr_p    = qpinfo->qpi_attrp;
        type      = qpinfo->qpi_type;
        port      = qpinfo->qpi_port;
        ibt_qphdl = qpinfo->qpi_ibt_qphdl;
        queuesz_p = qpinfo->qpi_queueszp;
        qphdl     = &qpinfo->qpi_qphdl;

        /*
         * Check for valid special QP type (only SMI & GSI supported)
         */
        if ((type != IBT_SMI_SQP) && (type != IBT_GSI_SQP)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_QP_SPECIAL_TYPE_INVALID, "invalid QP type");
                goto spec_qpalloc_fail;
        }

        /*
         * Check for valid port number
         */
        if (!tavor_portnum_is_valid(state, port)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_HCA_PORT_INVALID, "invalid port num");
                goto spec_qpalloc_fail;
        }
        port = port - 1;

        /*
         * Check for valid PD handle pointer
         */
        if (attr_p->qp_pd_hdl == NULL) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_PD_HDL_INVALID, "invalid PD handle");
                goto spec_qpalloc_fail;
        }
        pd = (tavor_pdhdl_t)attr_p->qp_pd_hdl;

        /* Increment the reference count on the PD */
        tavor_pd_refcnt_inc(pd);

        /*
         * Check for valid CQ handle pointers
         */
        if ((attr_p->qp_ibc_scq_hdl == NULL) ||
            (attr_p->qp_ibc_rcq_hdl == NULL)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_CQ_HDL_INVALID, "invalid CQ handle");
                goto spec_qpalloc_fail1;
        }
        sq_cq = (tavor_cqhdl_t)attr_p->qp_ibc_scq_hdl;
        rq_cq = (tavor_cqhdl_t)attr_p->qp_ibc_rcq_hdl;

        /*
         * Increment the reference count on the CQs.  One or both of these
         * could return error if we determine that the given CQ is already
         * being used with a non-special QP (i.e. a normal QP).
         */
        status = tavor_cq_refcnt_inc(sq_cq, TAVOR_CQ_IS_SPECIAL);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_CQ_HDL_INVALID, "invalid CQ handle");
                goto spec_qpalloc_fail1;
        }
        status = tavor_cq_refcnt_inc(rq_cq, TAVOR_CQ_IS_SPECIAL);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_CQ_HDL_INVALID, "invalid CQ handle");
                goto spec_qpalloc_fail2;
        }

        /*
         * Allocate the special QP resources.  Essentially, this allocation
         * amounts to checking if the request special QP has already been
         * allocated.  If successful, the QP context return is an actual
         * QP context that has been "aliased" to act as a special QP of the
         * appropriate type (and for the appropriate port).  Just as in
         * tavor_qp_alloc() above, ownership for this QP context is not
         * immediately given to hardware in the final step here.  Instead, we
         * wait until the QP is later transitioned to the "Init" state before
         * passing the QP to hardware.  If we fail here, we must undo all
         * the reference count (CQ and PD).
         */
        status = tavor_special_qp_rsrc_alloc(state, type, port, &qpc);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(status, "failed special QP rsrc");
                goto spec_qpalloc_fail3;
        }

        /*
         * Allocate the software structure for tracking the special queue
         * pair (i.e. the Tavor Queue Pair handle).  If we fail here, we
         * must undo the reference counts and the previous resource allocation.
         */
        status = tavor_rsrc_alloc(state, TAVOR_QPHDL, 1, sleepflag, &rsrc);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed QP handle");
                goto spec_qpalloc_fail4;
        }
        qp = (tavor_qphdl_t)rsrc->tr_addr;
        _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*qp))

        /*
         * Actual QP number is a combination of the index of the QPC and
         * the port number.  This is because the special QP contexts must
         * be allocated two-at-a-time.
         */
        qp->qp_qpnum = qpc->tr_indx + port;

        /*
         * Calculate the appropriate size for the work queues.
         * Note:  All Tavor QP work queues must be a power-of-2 in size.  Also
         * they may not be any smaller than TAVOR_QP_MIN_SIZE.  This step is
         * to round the requested size up to the next highest power-of-2
         */
        attr_p->qp_sizes.cs_sq = max(attr_p->qp_sizes.cs_sq, TAVOR_QP_MIN_SIZE);
        attr_p->qp_sizes.cs_rq = max(attr_p->qp_sizes.cs_rq, TAVOR_QP_MIN_SIZE);
        log_qp_sq_size = highbit(attr_p->qp_sizes.cs_sq);
        if (ISP2(attr_p->qp_sizes.cs_sq)) {
                log_qp_sq_size = log_qp_sq_size - 1;
        }
        log_qp_rq_size = highbit(attr_p->qp_sizes.cs_rq);
        if (ISP2(attr_p->qp_sizes.cs_rq)) {
                log_qp_rq_size = log_qp_rq_size - 1;
        }

        /*
         * Next we verify that the rounded-up size is valid (i.e. consistent
         * with the device limits and/or software-configured limits).  If not,
         * then obviously we have a bit of cleanup to do before returning.
         */
        if ((log_qp_sq_size > state->ts_cfg_profile->cp_log_max_qp_sz) ||
            (log_qp_rq_size > state->ts_cfg_profile->cp_log_max_qp_sz)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_HCA_WR_EXCEEDED, "max QP size");
                goto spec_qpalloc_fail5;
        }

        /*
         * Next we verify that the requested number of SGL is valid (i.e.
         * consistent with the device limits and/or software-configured
         * limits).  If not, then obviously the same cleanup needs to be done.
         */
        max_sgl = state->ts_cfg_profile->cp_wqe_real_max_sgl;
        if ((attr_p->qp_sizes.cs_sq_sgl > max_sgl) ||
            (attr_p->qp_sizes.cs_rq_sgl > max_sgl)) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_HCA_SGL_EXCEEDED, "max QP SGL");
                goto spec_qpalloc_fail5;
        }

        /*
         * Determine this QP's WQE sizes (for both the Send and Recv WQEs).
         * This will depend on the requested number of SGLs.  Note: this
         * has the side-effect of also calculating the real number of SGLs
         * (for the calculated WQE size).
         */
        tavor_qp_sgl_to_logwqesz(state, attr_p->qp_sizes.cs_rq_sgl,
            TAVOR_QP_WQ_TYPE_RECVQ, &qp->qp_rq_log_wqesz, &qp->qp_rq_sgl);
        if (type == IBT_SMI_SQP) {
                tavor_qp_sgl_to_logwqesz(state, attr_p->qp_sizes.cs_sq_sgl,
                    TAVOR_QP_WQ_TYPE_SENDMLX_QP0, &qp->qp_sq_log_wqesz,
                    &qp->qp_sq_sgl);
        } else {
                tavor_qp_sgl_to_logwqesz(state, attr_p->qp_sizes.cs_sq_sgl,
                    TAVOR_QP_WQ_TYPE_SENDMLX_QP1, &qp->qp_sq_log_wqesz,
                    &qp->qp_sq_sgl);
        }

        /*
         * Allocate the memory for QP work queues.  Note:  The location from
         * which we will allocate these work queues has been passed in
         * through the tavor_qp_options_t structure.  Since Tavor work queues
         * are not allowed to cross a 32-bit (4GB) boundary, the alignment of
         * the work queue memory is very important.  We used to allocate
         * work queues (the combined receive and send queues) so that they
         * would be aligned on their combined size.  That alignment guaranteed
         * that they would never cross the 4GB boundary (Tavor work queues
         * are on the order of MBs at maximum).  Now we are able to relax
         * this alignment constraint by ensuring that the IB address assigned
         * to the queue memory (as a result of the tavor_mr_register() call)
         * is offset from zero.
         * Previously, we had wanted to use the ddi_dma_mem_alloc() routine to
         * guarantee the alignment, but when attempting to use IOMMU bypass
         * mode we found that we were not allowed to specify any alignment
         * that was more restrictive than the system page size.
         * So we avoided this constraint by passing two alignment values,
         * one for the memory allocation itself and the other for the DMA
         * handle (for later bind).  This used to cause more memory than
         * necessary to be allocated (in order to guarantee the more
         * restrictive alignment contraint).  But be guaranteeing the
         * zero-based IB virtual address for the queue, we are able to
         * conserve this memory.
         */
        sq_wqe_size = 1 << qp->qp_sq_log_wqesz;
        rq_wqe_size = 1 << qp->qp_rq_log_wqesz;
        sq_size     = (1 << log_qp_sq_size) * sq_wqe_size;
        rq_size     = (1 << log_qp_rq_size) * rq_wqe_size;
        qp->qp_wqinfo.qa_size     = sq_size + rq_size;
        qp->qp_wqinfo.qa_alloc_align = max(sq_wqe_size, rq_wqe_size);
        qp->qp_wqinfo.qa_bind_align  = max(sq_wqe_size, rq_wqe_size);
        qp->qp_wqinfo.qa_location = wq_location;
        status = tavor_queue_alloc(state, &qp->qp_wqinfo, sleepflag);
        if (status != NULL) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed work queue");
                goto spec_qpalloc_fail5;
        }
        if (sq_wqe_size > rq_wqe_size) {
                sq_buf = qp->qp_wqinfo.qa_buf_aligned;
                rq_buf = (uint32_t *)((uintptr_t)sq_buf + sq_size);
        } else {
                rq_buf = qp->qp_wqinfo.qa_buf_aligned;
                sq_buf = (uint32_t *)((uintptr_t)rq_buf + rq_size);
        }

        /*
         * Register the memory for the special QP work queues.  The memory for
         * the special QP must be registered in the Tavor TPT tables.  This
         * gives us the LKey to specify in the QP context later.  Note: The
         * memory for Tavor work queues (both Send and Recv) must be contiguous
         * and registered as a single memory region.  Note also: If the work
         * queue is to be allocated from DDR memory, then only a "bypass"
         * mapping is appropriate.
         * Also, in order to meet the alignment restriction, we pass the
         * "mro_bind_override_addr" flag in the call to tavor_mr_register().
         * This guarantees that the resulting IB vaddr will be zero-based
         * (modulo the offset into the first page).
         * If we fail here, we have a bunch of resource and reference count
         * cleanup to do.
         */
        flag = (sleepflag == TAVOR_SLEEP) ? IBT_MR_SLEEP :
            IBT_MR_NOSLEEP;
        mr_attr.mr_vaddr    = (uint64_t)(uintptr_t)qp->qp_wqinfo.qa_buf_aligned;
        mr_attr.mr_len      = qp->qp_wqinfo.qa_size;
        mr_attr.mr_as       = NULL;
        mr_attr.mr_flags    = flag;
        if (wq_location == TAVOR_QUEUE_LOCATION_NORMAL) {
                mr_op.mro_bind_type = state->ts_cfg_profile->cp_iommu_bypass;

                dma_xfer_mode = state->ts_cfg_profile->cp_streaming_consistent;
                if (dma_xfer_mode == DDI_DMA_STREAMING) {
                        mr_attr.mr_flags |= IBT_MR_NONCOHERENT;
                }
        } else {
                mr_op.mro_bind_type = TAVOR_BINDMEM_BYPASS;
        }
        mr_op.mro_bind_dmahdl = qp->qp_wqinfo.qa_dmahdl;
        mr_op.mro_bind_override_addr = 1;
        status = tavor_mr_register(state, pd, &mr_attr, &mr, &mr_op);
        if (status != DDI_SUCCESS) {
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed register mr");
                goto spec_qpalloc_fail6;
        }

        /*
         * Calculate the offset between the kernel virtual address space
         * and the IB virtual address space.  This will be used when
         * posting work requests to properly initialize each WQE.
         */
        qp_desc_off = (uint64_t)(uintptr_t)qp->qp_wqinfo.qa_buf_aligned -
            (uint64_t)mr->mr_bindinfo.bi_addr;

        /*
         * Fill in all the return arguments (if necessary).  This includes
         * real work queue sizes, real SGLs, and QP number (which will be
         * either zero or one, depending on the special QP type)
         */
        if (queuesz_p != NULL) {
                queuesz_p->cs_sq        = (1 << log_qp_sq_size);
                queuesz_p->cs_sq_sgl    = qp->qp_sq_sgl;
                queuesz_p->cs_rq        = (1 << log_qp_rq_size);
                queuesz_p->cs_rq_sgl    = qp->qp_rq_sgl;
        }

        /*
         * Fill in the rest of the Tavor Queue Pair handle.  We can update
         * the following fields for use in further operations on the QP.
         */
        qp->qp_qpcrsrcp         = qpc;
        qp->qp_rsrcp            = rsrc;
        qp->qp_state            = TAVOR_QP_RESET;
        qp->qp_pdhdl            = pd;
        qp->qp_mrhdl            = mr;
        qp->qp_sq_sigtype       = (attr_p->qp_flags & IBT_WR_SIGNALED) ?
            TAVOR_QP_SQ_WR_SIGNALED : TAVOR_QP_SQ_ALL_SIGNALED;
        qp->qp_is_special       = (type == IBT_SMI_SQP) ?
            TAVOR_QP_SMI : TAVOR_QP_GSI;
        qp->qp_is_umap          = 0;
        qp->qp_uarpg            = 0;
        qp->qp_sq_cqhdl         = sq_cq;
        qp->qp_sq_lastwqeaddr   = NULL;
        qp->qp_sq_bufsz         = (1 << log_qp_sq_size);
        qp->qp_sq_buf           = sq_buf;
        qp->qp_desc_off         = qp_desc_off;
        qp->qp_rq_cqhdl         = rq_cq;
        qp->qp_rq_lastwqeaddr   = NULL;
        qp->qp_rq_bufsz         = (1 << log_qp_rq_size);
        qp->qp_rq_buf           = rq_buf;
        qp->qp_portnum          = port;
        qp->qp_pkeyindx         = 0;
        qp->qp_hdlrarg          = (void *)ibt_qphdl;
        qp->qp_mcg_refcnt       = 0;
        qp->qp_srq_en           = 0;
        qp->qp_srqhdl           = NULL;

        /* Determine if later ddi_dma_sync will be necessary */
        qp->qp_sync = TAVOR_QP_IS_SYNC_REQ(state, qp->qp_wqinfo);

        /* All special QPs are UD QP service type */
        qp->qp_serv_type = TAVOR_QP_UD;

        /* Zero out the QP context */
        bzero(&qp->qpc, sizeof (tavor_hw_qpc_t));

        /*
         * Put QP handle in Tavor QPNum-to-QPHdl list.  Then fill in the
         * "qphdl" and return success
         */
        ASSERT(state->ts_qphdl[qpc->tr_indx + port] == NULL);
        state->ts_qphdl[qpc->tr_indx + port] = qp;

        *qphdl = qp;

        TAVOR_TNF_EXIT(tavor_special_qp_alloc);
        return (DDI_SUCCESS);

/*
 * The following is cleanup for all possible failure cases in this routine
 */
spec_qpalloc_fail6:
        tavor_queue_free(state, &qp->qp_wqinfo);
spec_qpalloc_fail5:
        tavor_rsrc_free(state, &rsrc);
spec_qpalloc_fail4:
        if (tavor_special_qp_rsrc_free(state, type, port) != DDI_SUCCESS) {
                TAVOR_WARNING(state, "failed to free special QP rsrc");
        }
spec_qpalloc_fail3:
        tavor_cq_refcnt_dec(rq_cq);
spec_qpalloc_fail2:
        tavor_cq_refcnt_dec(sq_cq);
spec_qpalloc_fail1:
        tavor_pd_refcnt_dec(pd);
spec_qpalloc_fail:
        TNF_PROBE_1(tavor_special_qp_alloc_fail, TAVOR_TNF_ERROR, "",
            tnf_string, msg, errormsg);
        TAVOR_TNF_EXIT(tavor_special_qp_alloc);
        return (status);
}


/*
 * tavor_qp_free()
 *    This function frees up the QP resources.  Depending on the value
 *    of the "free_qp_flags", the QP number may not be released until
 *    a subsequent call to tavor_qp_release_qpn().
 *
 *    Context: Can be called only from user or kernel context.
 */
/* ARGSUSED */
int
tavor_qp_free(tavor_state_t *state, tavor_qphdl_t *qphdl,
    ibc_free_qp_flags_t free_qp_flags, ibc_qpn_hdl_t *qpnh,
    uint_t sleepflag)
{
        tavor_rsrc_t            *qpc, *rdb, *rsrc;
        tavor_umap_db_entry_t   *umapdb;
        tavor_qpn_entry_t       *entry;
        tavor_pdhdl_t           pd;
        tavor_mrhdl_t           mr;
        tavor_cqhdl_t           sq_cq, rq_cq;
        tavor_srqhdl_t          srq;
        tavor_qphdl_t           qp;
        uint64_t                value;
        uint_t                  type, port;
        uint_t                  maxprot;
        uint_t                  qp_srq_en;
        int                     status;
        char                    *errormsg;

        TAVOR_TNF_ENTER(tavor_qp_free);

        /*
         * Pull all the necessary information from the Tavor Queue Pair
         * handle.  This is necessary here because the resource for the
         * QP handle is going to be freed up as part of this operation.
         */
        qp      = *qphdl;
        mutex_enter(&qp->qp_lock);
        qpc     = qp->qp_qpcrsrcp;
        rsrc    = qp->qp_rsrcp;
        pd      = qp->qp_pdhdl;
        srq     = qp->qp_srqhdl;
        mr      = qp->qp_mrhdl;
        rq_cq   = qp->qp_rq_cqhdl;
        sq_cq   = qp->qp_sq_cqhdl;
        rdb     = qp->qp_rdbrsrcp;
        port    = qp->qp_portnum;
        qp_srq_en = qp->qp_srq_en;

        /*
         * If the QP is part of an MCG, then we fail the qp_free
         */
        if (qp->qp_mcg_refcnt != 0) {
                mutex_exit(&qp->qp_lock);
                TAVOR_TNF_FAIL(ibc_get_ci_failure(0), "QP part of MCG on free");
                goto qpfree_fail;
        }

        /*
         * If the QP is not already in "Reset" state, then transition to
         * "Reset".  This is necessary because software does not reclaim
         * ownership of the QP context until the QP is in the "Reset" state.
         * If the ownership transfer fails for any reason, then it is an
         * indication that something (either in HW or SW) has gone seriously
         * wrong.  So we print a warning message and return.
         */
        if (qp->qp_state != TAVOR_QP_RESET) {
                if (tavor_qp_to_reset(state, qp) != DDI_SUCCESS) {
                        mutex_exit(&qp->qp_lock);
                        TAVOR_WARNING(state, "failed to reset QP context");
                        /* Set "status" and "errormsg" and goto failure */
                        TAVOR_TNF_FAIL(ibc_get_ci_failure(0),
                            "reset QP context");
                        goto qpfree_fail;
                }
                qp->qp_state = TAVOR_QP_RESET;

                /*
                 * Do any additional handling necessary for the transition
                 * to the "Reset" state (e.g. update the WRID lists)
                 */
                tavor_wrid_to_reset_handling(state, qp);
        }

        /*
         * If this was a user-mappable QP, then we need to remove its entry
         * from the "userland resources database".  If it is also currently
         * mmap()'d out to a user process, then we need to call
         * devmap_devmem_remap() to remap the QP memory to an invalid mapping.
         * We also need to invalidate the QP tracking information for the
         * user mapping.
         */
        if (qp->qp_is_umap) {
                status = tavor_umap_db_find(state->ts_instance, qp->qp_qpnum,
                    MLNX_UMAP_QPMEM_RSRC, &value, TAVOR_UMAP_DB_REMOVE,
                    &umapdb);
                if (status != DDI_SUCCESS) {
                        mutex_exit(&qp->qp_lock);
                        TAVOR_WARNING(state, "failed to find in database");
                        TAVOR_TNF_EXIT(tavor_qp_free);
                        return (ibc_get_ci_failure(0));
                }
                tavor_umap_db_free(umapdb);
                if (qp->qp_umap_dhp != NULL) {
                        maxprot = (PROT_READ | PROT_WRITE | PROT_USER);
                        status = devmap_devmem_remap(qp->qp_umap_dhp,
                            state->ts_dip, 0, 0, qp->qp_wqinfo.qa_size,
                            maxprot, DEVMAP_MAPPING_INVALID, NULL);
                        if (status != DDI_SUCCESS) {
                                mutex_exit(&qp->qp_lock);
                                TAVOR_WARNING(state, "failed in QP memory "
                                    "devmap_devmem_remap()");
                                TAVOR_TNF_EXIT(tavor_qp_free);
                                return (ibc_get_ci_failure(0));
                        }
                        qp->qp_umap_dhp = (devmap_cookie_t)NULL;
                }
        }

        /*
         * Put NULL into the Tavor QPNum-to-QPHdl list.  This will allow any
         * in-progress events to detect that the QP corresponding to this
         * number has been freed.  Note: it does depend in whether we are
         * freeing a special QP or not.
         */
        if (qp->qp_is_special) {
                state->ts_qphdl[qpc->tr_indx + port] = NULL;
        } else {
                state->ts_qphdl[qpc->tr_indx] = NULL;
        }

        /*
         * Drop the QP lock
         *    At this point the lock is no longer necessary.  We cannot
         *    protect from multiple simultaneous calls to free the same QP.
         *    In addition, since the QP lock is contained in the QP "software
         *    handle" resource, which we will free (see below), it is
         *    important that we have no further references to that memory.
         */
        mutex_exit(&qp->qp_lock);
        _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*qp))

        /*
         * Free the QP resources
         *    Start by deregistering and freeing the memory for work queues.
         *    Next free any previously allocated context information
         *    (depending on QP type)
         *    Finally, decrement the necessary reference counts.
         * If this fails for any reason, then it is an indication that
         * something (either in HW or SW) has gone seriously wrong.  So we
         * print a warning message and return.
         */
        status = tavor_mr_deregister(state, &mr, TAVOR_MR_DEREG_ALL,
            sleepflag);
        if (status != DDI_SUCCESS) {
                TAVOR_WARNING(state, "failed to deregister QP memory");
                /* Set "status" and "errormsg" and goto failure */
                TAVOR_TNF_FAIL(ibc_get_ci_failure(0), "failed deregister mr");
                goto qpfree_fail;
        }

        /* Free the memory for the QP */
        tavor_queue_free(state, &qp->qp_wqinfo);

        /*
         * Free up the remainder of the QP resources.  Note: we have a few
         * different resources to free up depending on whether the QP is a
         * special QP or not.  As described above, if any of these fail for
         * any reason it is an indication that something (either in HW or SW)
         * has gone seriously wrong.  So we print a warning message and
         * return.
         */
        if (qp->qp_is_special) {
                type = (qp->qp_is_special == TAVOR_QP_SMI) ?
                    IBT_SMI_SQP : IBT_GSI_SQP;

                /* Free up resources for the special QP */
                status = tavor_special_qp_rsrc_free(state, type, port);
                if (status != DDI_SUCCESS) {
                        TAVOR_WARNING(state, "failed to free special QP rsrc");
                        /* Set "status" and "errormsg" and goto failure */
                        TAVOR_TNF_FAIL(ibc_get_ci_failure(0),
                            "failed special QP rsrc");
                        goto qpfree_fail;
                }

        } else {
                type = qp->qp_serv_type;

                /* Free up the RDB entries resource */
                if (type == TAVOR_QP_RC) {
                        tavor_rsrc_free(state, &rdb);
                }

                /*
                 * Check the flags and determine whether to release the
                 * QPN or not, based on their value.
                 */
                if (free_qp_flags == IBC_FREE_QP_ONLY) {
                        entry = qp->qp_qpn_hdl;
                        tavor_qp_release_qpn(state, qp->qp_qpn_hdl,
                            TAVOR_QPN_FREE_ONLY);
                        *qpnh = (ibc_qpn_hdl_t)entry;
                } else {
                        tavor_qp_release_qpn(state, qp->qp_qpn_hdl,
                            TAVOR_QPN_RELEASE);
                }
        }

        /* Free the Tavor Queue Pair handle */
        tavor_rsrc_free(state, &rsrc);

        /* Decrement the reference counts on CQs, PD and SRQ (if needed) */
        tavor_cq_refcnt_dec(rq_cq);
        tavor_cq_refcnt_dec(sq_cq);
        tavor_pd_refcnt_dec(pd);
        if (qp_srq_en == TAVOR_QP_SRQ_ENABLED) {
                tavor_srq_refcnt_dec(srq);
        }

        /* Set the qphdl pointer to NULL and return success */
        *qphdl = NULL;

        TAVOR_TNF_EXIT(tavor_qp_free);
        return (DDI_SUCCESS);

qpfree_fail:
        TNF_PROBE_1(tavor_qp_free_fail, TAVOR_TNF_ERROR, "",
            tnf_string, msg, errormsg);
        TAVOR_TNF_EXIT(tavor_qp_free);
        return (status);
}


/*
 * tavor_qp_query()
 *    Context: Can be called from interrupt or base context.
 */
int
tavor_qp_query(tavor_state_t *state, tavor_qphdl_t qp,
    ibt_qp_query_attr_t *attr_p)
{
        ibt_cep_state_t         qp_state;
        ibt_qp_ud_attr_t        *ud;
        ibt_qp_rc_attr_t        *rc;
        ibt_qp_uc_attr_t        *uc;
        ibt_cep_flags_t         enable_flags;
        tavor_hw_addr_path_t    *qpc_path, *qpc_alt_path;
        ibt_cep_path_t          *path_ptr, *alt_path_ptr;
        tavor_hw_qpc_t          *qpc;
        int                     status;

        TAVOR_TNF_ENTER(tavor_qp_query);

        mutex_enter(&qp->qp_lock);

        /*
         * Grab the temporary QPC entry from QP software state
         */
        qpc = &qp->qpc;

        /* Convert the current Tavor QP state to IBTF QP state */
        switch (qp->qp_state) {
        case TAVOR_QP_RESET:
                qp_state = IBT_STATE_RESET;             /* "Reset" */
                break;
        case TAVOR_QP_INIT:
                qp_state = IBT_STATE_INIT;              /* Initialized */
                break;
        case TAVOR_QP_RTR:
                qp_state = IBT_STATE_RTR;               /* Ready to Receive */
                break;
        case TAVOR_QP_RTS:
                qp_state = IBT_STATE_RTS;               /* Ready to Send */
                break;
        case TAVOR_QP_SQERR:
                qp_state = IBT_STATE_SQE;               /* Send Queue Error */
                break;
        case TAVOR_QP_SQD:
                if (qp->qp_sqd_still_draining) {
                        qp_state = IBT_STATE_SQDRAIN;   /* SQ Draining */
                } else {
                        qp_state = IBT_STATE_SQD;       /* SQ Drained */
                }
                break;
        case TAVOR_QP_ERR:
                qp_state = IBT_STATE_ERROR;             /* Error */
                break;
        default:
                mutex_exit(&qp->qp_lock);
                TNF_PROBE_1(tavor_qp_query_inv_qpstate_fail,
                    TAVOR_TNF_ERROR, "", tnf_uint, qpstate, qp->qp_state);
                TAVOR_TNF_EXIT(tavor_qp_query);
                return (ibc_get_ci_failure(0));
        }
        attr_p->qp_info.qp_state = qp_state;

        /* SRQ Hook. */
        attr_p->qp_srq = NULL;

        /*
         * The following QP information is always returned, regardless of
         * the current QP state.  Note: Some special handling is necessary
         * for calculating the QP number on special QP (QP0 and QP1).
         */
        attr_p->qp_sq_cq    = qp->qp_sq_cqhdl->cq_hdlrarg;
        attr_p->qp_rq_cq    = qp->qp_rq_cqhdl->cq_hdlrarg;
        if (qp->qp_is_special) {
                attr_p->qp_qpn = (qp->qp_is_special == TAVOR_QP_SMI) ? 0 : 1;
        } else {
                attr_p->qp_qpn = (ib_qpn_t)qp->qp_qpnum;
        }
        attr_p->qp_sq_sgl   = qp->qp_sq_sgl;
        attr_p->qp_rq_sgl   = qp->qp_rq_sgl;
        attr_p->qp_info.qp_sq_sz = qp->qp_sq_bufsz;
        attr_p->qp_info.qp_rq_sz = qp->qp_rq_bufsz;

        /*
         * If QP is currently in the "Reset" state, then only the above are
         * returned
         */
        if (qp_state == IBT_STATE_RESET) {
                mutex_exit(&qp->qp_lock);
                TAVOR_TNF_EXIT(tavor_qp_query);
                return (DDI_SUCCESS);
        }

        /*
         * Post QUERY_QP command to firmware
         *
         * We do a TAVOR_NOSLEEP here because we are holding the "qp_lock".
         * Since we may be in the interrupt context (or subsequently raised
         * to interrupt level by priority inversion), we do not want to block
         * in this routine waiting for success.
         */
        status = tavor_cmn_query_cmd_post(state, QUERY_QP, qp->qp_qpnum,
            qpc, sizeof (tavor_hw_qpc_t), TAVOR_CMD_NOSLEEP_SPIN);
        if (status != TAVOR_CMD_SUCCESS) {
                mutex_exit(&qp->qp_lock);
                cmn_err(CE_CONT, "Tavor: QUERY_QP command failed: %08x\n",
                    status);
                TNF_PROBE_1(tavor_qp_query_cmd_fail, TAVOR_TNF_ERROR, "",
                    tnf_uint, status, status);
                TAVOR_TNF_EXIT(tavor_qp_query);
                return (ibc_get_ci_failure(0));
        }

        /*
         * Fill in the additional QP info based on the QP's transport type.
         */
        if (qp->qp_serv_type == TAVOR_QP_UD) {

                /* Fill in the UD-specific info */
                ud = &attr_p->qp_info.qp_transport.ud;
                ud->ud_qkey     = (ib_qkey_t)qpc->qkey;
                ud->ud_sq_psn   = qpc->next_snd_psn;
                ud->ud_pkey_ix  = qpc->pri_addr_path.pkey_indx;
                ud->ud_port     = qpc->pri_addr_path.portnum;

                attr_p->qp_info.qp_trans = IBT_UD_SRV;

        } else if (qp->qp_serv_type == TAVOR_QP_RC) {

                /* Fill in the RC-specific info */
                rc = &attr_p->qp_info.qp_transport.rc;
                rc->rc_sq_psn   = qpc->next_snd_psn;
                rc->rc_rq_psn   = qpc->next_rcv_psn;
                rc->rc_dst_qpn  = qpc->rem_qpn;

                /* Grab the path migration state information */
                if (qpc->pm_state == TAVOR_QP_PMSTATE_MIGRATED) {
                        rc->rc_mig_state = IBT_STATE_MIGRATED;
                } else if (qpc->pm_state == TAVOR_QP_PMSTATE_REARM) {
                        rc->rc_mig_state = IBT_STATE_REARMED;
                } else {
                        rc->rc_mig_state = IBT_STATE_ARMED;
                }
                rc->rc_rdma_ra_out = (1 << qpc->sra_max);
                rc->rc_rdma_ra_in  = (1 << qpc->rra_max);
                rc->rc_min_rnr_nak = qpc->min_rnr_nak;
                rc->rc_path_mtu    = qpc->mtu;
                rc->rc_retry_cnt   = qpc->retry_cnt;

                /* Get the common primary address path fields */
                qpc_path = &qpc->pri_addr_path;
                path_ptr = &rc->rc_path;
                tavor_get_addr_path(state, qpc_path, &path_ptr->cep_adds_vect,
                    TAVOR_ADDRPATH_QP, qp);

                /* Fill in the additional primary address path fields */
                path_ptr->cep_pkey_ix      = qpc_path->pkey_indx;
                path_ptr->cep_hca_port_num = qpc_path->portnum;
                path_ptr->cep_timeout      = qpc_path->ack_timeout;

                /* Get the common alternate address path fields */
                qpc_alt_path = &qpc->alt_addr_path;
                alt_path_ptr = &rc->rc_alt_path;
                tavor_get_addr_path(state, qpc_alt_path,
                    &alt_path_ptr->cep_adds_vect, TAVOR_ADDRPATH_QP, qp);

                /* Fill in the additional alternate address path fields */
                alt_path_ptr->cep_pkey_ix       = qpc_alt_path->pkey_indx;
                alt_path_ptr->cep_hca_port_num  = qpc_alt_path->portnum;
                alt_path_ptr->cep_timeout       = qpc_alt_path->ack_timeout;

                /* Get the RNR retry time from primary path */
                rc->rc_rnr_retry_cnt = qpc_path->rnr_retry;

                /* Set the enable flags based on RDMA/Atomic enable bits */
                enable_flags = IBT_CEP_NO_FLAGS;
                enable_flags |= ((qpc->rre == 0) ? 0 : IBT_CEP_RDMA_RD);
                enable_flags |= ((qpc->rwe == 0) ? 0 : IBT_CEP_RDMA_WR);
                enable_flags |= ((qpc->rae == 0) ? 0 : IBT_CEP_ATOMIC);
                attr_p->qp_info.qp_flags = enable_flags;

                attr_p->qp_info.qp_trans = IBT_RC_SRV;

        } else if (qp->qp_serv_type == TAVOR_QP_UC) {

                /* Fill in the UC-specific info */
                uc = &attr_p->qp_info.qp_transport.uc;
                uc->uc_sq_psn   = qpc->next_snd_psn;
                uc->uc_rq_psn   = qpc->next_rcv_psn;
                uc->uc_dst_qpn  = qpc->rem_qpn;

                /* Grab the path migration state information */
                if (qpc->pm_state == TAVOR_QP_PMSTATE_MIGRATED) {
                        uc->uc_mig_state = IBT_STATE_MIGRATED;
                } else if (qpc->pm_state == TAVOR_QP_PMSTATE_REARM) {
                        uc->uc_mig_state = IBT_STATE_REARMED;
                } else {
                        uc->uc_mig_state = IBT_STATE_ARMED;
                }
                uc->uc_path_mtu = qpc->mtu;

                /* Get the common primary address path fields */
                qpc_path = &qpc->pri_addr_path;
                path_ptr = &uc->uc_path;
                tavor_get_addr_path(state, qpc_path, &path_ptr->cep_adds_vect,
                    TAVOR_ADDRPATH_QP, qp);

                /* Fill in the additional primary address path fields */
                path_ptr->cep_pkey_ix      = qpc_path->pkey_indx;
                path_ptr->cep_hca_port_num = qpc_path->portnum;

                /* Get the common alternate address path fields */
                qpc_alt_path = &qpc->alt_addr_path;
                alt_path_ptr = &uc->uc_alt_path;
                tavor_get_addr_path(state, qpc_alt_path,
                    &alt_path_ptr->cep_adds_vect, TAVOR_ADDRPATH_QP, qp);

                /* Fill in the additional alternate address path fields */
                alt_path_ptr->cep_pkey_ix       = qpc_alt_path->pkey_indx;
                alt_path_ptr->cep_hca_port_num  = qpc_alt_path->portnum;

                /*
                 * Set the enable flags based on RDMA enable bits (by
                 * definition UC doesn't support Atomic or RDMA Read)
                 */
                enable_flags = ((qpc->rwe == 0) ? 0 : IBT_CEP_RDMA_WR);
                attr_p->qp_info.qp_flags = enable_flags;

                attr_p->qp_info.qp_trans = IBT_UC_SRV;

        } else {
                TAVOR_WARNING(state, "unexpected QP transport type");
                mutex_exit(&qp->qp_lock);
                return (ibc_get_ci_failure(0));
        }

        /*
         * Under certain circumstances it is possible for the Tavor hardware
         * to transition to one of the error states without software directly
         * knowing about it.  The QueryQP() call is the one place where we
         * have an opportunity to sample and update our view of the QP state.
         */
        if (qpc->state == TAVOR_QP_SQERR) {
                attr_p->qp_info.qp_state = IBT_STATE_SQE;
                qp->qp_state = TAVOR_QP_SQERR;
        }
        if (qpc->state == TAVOR_QP_ERR) {
                attr_p->qp_info.qp_state = IBT_STATE_ERROR;
                qp->qp_state = TAVOR_QP_ERR;
        }
        mutex_exit(&qp->qp_lock);

        TAVOR_TNF_EXIT(tavor_qp_query);
        return (DDI_SUCCESS);
}


/*
 * tavor_qp_create_qpn()
 *    Context: Can be called from interrupt or base context.
 */
static int
tavor_qp_create_qpn(tavor_state_t *state, tavor_qphdl_t qp, tavor_rsrc_t *qpc)
{
        tavor_qpn_entry_t       query;
        tavor_qpn_entry_t       *entry;
        avl_index_t             where;

        TAVOR_TNF_ENTER(tavor_qp_create_qpn);

        /*
         * Build a query (for the AVL tree lookup) and attempt to find
         * a previously added entry that has a matching QPC index.  If
         * no matching entry is found, then allocate, initialize, and
         * add an entry to the AVL tree.
         * If a matching entry is found, then increment its QPN counter
         * and reference counter.
         */
        query.qpn_indx = qpc->tr_indx;
        mutex_enter(&state->ts_qpn_avl_lock);
        entry = (tavor_qpn_entry_t *)avl_find(&state->ts_qpn_avl,
            &query, &where);
        if (entry == NULL) {
                /*
                 * Allocate and initialize a QPN entry, then insert
                 * it into the AVL tree.
                 */
                entry = (tavor_qpn_entry_t *)kmem_zalloc(
                    sizeof (tavor_qpn_entry_t), KM_NOSLEEP);
                if (entry == NULL) {
                        mutex_exit(&state->ts_qpn_avl_lock);
                        TAVOR_TNF_EXIT(tavor_qp_create_qpn);
                        return (DDI_FAILURE);
                }
                _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*entry))

                entry->qpn_indx    = qpc->tr_indx;
                entry->qpn_refcnt  = 0;
                entry->qpn_counter = 0;

                avl_insert(&state->ts_qpn_avl, entry, where);
        }

        /*
         * Make the AVL tree entry point to the QP context resource that
         * it will be responsible for tracking
         */
        entry->qpn_qpc = qpc;

        /*
         * Setup the QP handle to point to the AVL tree entry.  Then
         * generate the new QP number from the entry's QPN counter value
         * and the hardware's QP context table index.
         */
        qp->qp_qpn_hdl  = entry;
        qp->qp_qpnum    = ((entry->qpn_counter <<
            state->ts_cfg_profile->cp_log_num_qp) | qpc->tr_indx) &
            TAVOR_QP_MAXNUMBER_MSK;

        /*
         * Increment the reference counter and QPN counter.  The QPN
         * counter always indicates the next available number for use.
         */
        entry->qpn_counter++;
        entry->qpn_refcnt++;

        mutex_exit(&state->ts_qpn_avl_lock);
        TAVOR_TNF_EXIT(tavor_qp_create_qpn);
        return (DDI_SUCCESS);
}


/*
 * tavor_qp_release_qpn()
 *    Context: Can be called only from user or kernel context.
 */
void
tavor_qp_release_qpn(tavor_state_t *state, tavor_qpn_entry_t *entry, int flags)
{
        TAVOR_TNF_ENTER(tavor_qp_release_qpn);

        ASSERT(entry != NULL);

        mutex_enter(&state->ts_qpn_avl_lock);

        /*
         * If we are releasing the QP number here, then we decrement the
         * reference count and check for zero references.  If there are
         * zero references, then we free the QPC context (if it hadn't
         * already been freed during a TAVOR_QPN_FREE_ONLY free, i.e. for
         * reuse with another similar QP number) and remove the tracking
         * structure from the QP number AVL tree and free the structure.
         * If we are not releasing the QP number here, then, as long as we
         * have not exhausted the usefulness of the QPC context (that is,
         * re-used it too many times without the reference count having
         * gone to zero), we free up the QPC context for use by another
         * thread (which will use it to construct a different QP number
         * from the same QPC table index).
         */
        if (flags == TAVOR_QPN_RELEASE) {
                entry->qpn_refcnt--;

                /*
                 * If the reference count is zero, then we free the QPC
                 * context (if it hadn't already been freed in an early
                 * step, e.g. TAVOR_QPN_FREE_ONLY) and remove/free the
                 * tracking structure from the QP number AVL tree.
                 */
                if (entry->qpn_refcnt == 0) {
                        if (entry->qpn_qpc != NULL) {
                                tavor_rsrc_free(state, &entry->qpn_qpc);
                        }

                        /*
                         * If the current entry has served it's useful
                         * purpose (i.e. been reused the maximum allowable
                         * number of times), then remove it from QP number
                         * AVL tree and free it up.
                         */
                        if (entry->qpn_counter >= (1 <<
                            (24 - state->ts_cfg_profile->cp_log_num_qp))) {
                                avl_remove(&state->ts_qpn_avl, entry);
                                kmem_free(entry, sizeof (tavor_qpn_entry_t));
                        }
                }

        } else if (flags == TAVOR_QPN_FREE_ONLY) {
                /*
                 * Even if we are not freeing the QP number, that will not
                 * always prevent us from releasing the QPC context.  In fact,
                 * since the QPC context only forms part of the whole QPN,
                 * we want to free it up for use by other consumers.  But
                 * if the reference count is non-zero (which it will always
                 * be when we are doing TAVOR_QPN_FREE_ONLY) and the counter
                 * has reached its maximum value, then we cannot reuse the
                 * QPC context until the reference count eventually reaches
                 * zero (in TAVOR_QPN_RELEASE, above).
                 */
                if (entry->qpn_counter < (1 <<
                    (24 - state->ts_cfg_profile->cp_log_num_qp))) {
                        tavor_rsrc_free(state, &entry->qpn_qpc);
                }
        }
        mutex_exit(&state->ts_qpn_avl_lock);

        TAVOR_TNF_EXIT(tavor_qp_release_qpn);
}


/*
 * tavor_qpn_db_compare()
 *    Context: Can be called from user or kernel context.
 */
static int
tavor_qpn_avl_compare(const void *q, const void *e)
{
        tavor_qpn_entry_t       *entry, *query;

        TAVOR_TNF_ENTER(tavor_qpn_avl_compare);

        entry = (tavor_qpn_entry_t *)e;
        query = (tavor_qpn_entry_t *)q;

        if (query->qpn_indx < entry->qpn_indx) {
                TAVOR_TNF_EXIT(tavor_qpn_avl_compare);
                return (-1);
        } else if (query->qpn_indx > entry->qpn_indx) {
                TAVOR_TNF_EXIT(tavor_qpn_avl_compare);
                return (+1);
        } else {
                TAVOR_TNF_EXIT(tavor_qpn_avl_compare);
                return (0);
        }
}


/*
 * tavor_qpn_avl_init()
 *    Context: Only called from attach() path context
 */
void
tavor_qpn_avl_init(tavor_state_t *state)
{
        TAVOR_TNF_ENTER(tavor_qpn_avl_init);

        /* Initialize the lock used for QP number (QPN) AVL tree access */
        mutex_init(&state->ts_qpn_avl_lock, NULL, MUTEX_DRIVER,
            DDI_INTR_PRI(state->ts_intrmsi_pri));

        /* Initialize the AVL tree for the QP number (QPN) storage */
        avl_create(&state->ts_qpn_avl, tavor_qpn_avl_compare,
            sizeof (tavor_qpn_entry_t),
            offsetof(tavor_qpn_entry_t, qpn_avlnode));

        TAVOR_TNF_EXIT(tavor_qpn_avl_init);
}


/*
 * tavor_qpn_avl_fini()
 *    Context: Only called from attach() and/or detach() path contexts
 */
void
tavor_qpn_avl_fini(tavor_state_t *state)
{
        tavor_qpn_entry_t       *entry;
        void                    *cookie;

        TAVOR_TNF_ENTER(tavor_qpn_avl_fini);

        /*
         * Empty all entries (if necessary) and destroy the AVL tree
         * that was used for QP number (QPN) tracking.
         */
        cookie = NULL;
        while ((entry = (tavor_qpn_entry_t *)avl_destroy_nodes(
            &state->ts_qpn_avl, &cookie)) != NULL) {
                kmem_free(entry, sizeof (tavor_qpn_entry_t));
        }
        avl_destroy(&state->ts_qpn_avl);

        /* Destroy the lock used for QP number (QPN) AVL tree access */
        mutex_destroy(&state->ts_qpn_avl_lock);

        TAVOR_TNF_EXIT(tavor_qpn_avl_fini);
}


/*
 * tavor_qphdl_from_qpnum()
 *    Context: Can be called from interrupt or base context.
 *
 *    This routine is important because changing the unconstrained
 *    portion of the QP number is critical to the detection of a
 *    potential race condition in the QP event handler code (i.e. the case
 *    where a QP is freed and alloc'd again before an event for the
 *    "old" QP can be handled).
 *
 *    While this is not a perfect solution (not sure that one exists)
 *    it does help to mitigate the chance that this race condition will
 *    cause us to deliver a "stale" event to the new QP owner.  Note:
 *    this solution does not scale well because the number of constrained
 *    bits increases (and, hence, the number of unconstrained bits
 *    decreases) as the number of supported QPs grows.  For small and
 *    intermediate values, it should hopefully provide sufficient
 *    protection.
 */
tavor_qphdl_t
tavor_qphdl_from_qpnum(tavor_state_t *state, uint_t qpnum)
{
        uint_t  qpindx, qpmask;

        /* Calculate the QP table index from the qpnum */
        qpmask = (1 << state->ts_cfg_profile->cp_log_num_qp) - 1;
        qpindx = qpnum & qpmask;
        return (state->ts_qphdl[qpindx]);
}


/*
 * tavor_special_qp_rsrc_alloc
 *    Context: Can be called from interrupt or base context.
 */
static int
tavor_special_qp_rsrc_alloc(tavor_state_t *state, ibt_sqp_type_t type,
    uint_t port, tavor_rsrc_t **qp_rsrc)
{
        uint_t          mask, flags;
        int             status;

        TAVOR_TNF_ENTER(tavor_special_qp_rsrc_alloc);

        mutex_enter(&state->ts_spec_qplock);
        flags = state->ts_spec_qpflags;
        if (type == IBT_SMI_SQP) {
                /*
                 * Check here to see if the driver has been configured
                 * to instruct the Tavor firmware to handle all incoming
                 * SMP messages (i.e. messages sent to SMA).  If so,
                 * then we will treat QP0 as if it has already been
                 * allocated (for internal use).  Otherwise, if we allow
                 * the allocation to happen, it will cause unexpected
                 * behaviors (e.g. Tavor SMA becomes unresponsive).
                 */
                if (state->ts_cfg_profile->cp_qp0_agents_in_fw != 0) {
                        mutex_exit(&state->ts_spec_qplock);
                        TNF_PROBE_0(tavor_special_qp0_alloc_already_in_fw,
                            TAVOR_TNF_ERROR, "");
                        TAVOR_TNF_EXIT(tavor_special_qp_rsrc_alloc);
                        return (IBT_QP_IN_USE);
                }

                /*
                 * If this is the first QP0 allocation, then post
                 * a CONF_SPECIAL_QP firmware command
                 */
                if ((flags & TAVOR_SPECIAL_QP0_RSRC_MASK) == 0) {
                        status = tavor_conf_special_qp_cmd_post(state,
                            state->ts_spec_qp0->tr_indx, TAVOR_CMD_QP_SMI,
                            TAVOR_CMD_NOSLEEP_SPIN);
                        if (status != TAVOR_CMD_SUCCESS) {
                                mutex_exit(&state->ts_spec_qplock);
                                cmn_err(CE_CONT, "Tavor: CONF_SPECIAL_QP "
                                    "command failed: %08x\n", status);
                                TNF_PROBE_1(tavor_conf_special_qp_cmd_fail,
                                    TAVOR_TNF_ERROR, "", tnf_uint, status,
                                    status);
                                TAVOR_TNF_EXIT(tavor_special_qp_rsrc_alloc);
                                return (IBT_INSUFF_RESOURCE);
                        }
                }

                /*
                 * Now check (and, if necessary, modify) the flags to indicate
                 * whether the allocation was successful
                 */
                mask = (1 << (TAVOR_SPECIAL_QP0_RSRC + port));
                if (flags & mask) {
                        mutex_exit(&state->ts_spec_qplock);
                        TNF_PROBE_1(tavor_ts_spec_qp0_alloc_already,
                            TAVOR_TNF_ERROR, "", tnf_uint, port, port);
                        TAVOR_TNF_EXIT(tavor_special_qp_rsrc_alloc);
                        return (IBT_QP_IN_USE);
                }
                state->ts_spec_qpflags |= mask;
                *qp_rsrc = state->ts_spec_qp0;

        } else {
                /*
                 * If this is the first QP1 allocation, then post
                 * a CONF_SPECIAL_QP firmware command
                 */
                if ((flags & TAVOR_SPECIAL_QP1_RSRC_MASK) == 0) {
                        status = tavor_conf_special_qp_cmd_post(state,
                            state->ts_spec_qp1->tr_indx, TAVOR_CMD_QP_GSI,
                            TAVOR_CMD_NOSLEEP_SPIN);
                        if (status != TAVOR_CMD_SUCCESS) {
                                mutex_exit(&state->ts_spec_qplock);
                                cmn_err(CE_CONT, "Tavor: CONF_SPECIAL_QP "
                                    "command failed: %08x\n", status);
                                TNF_PROBE_1(tavor_conf_special_qp_cmd_fail,
                                    TAVOR_TNF_ERROR, "", tnf_uint, status,
                                    status);
                                TAVOR_TNF_EXIT(tavor_special_qp_rsrc_alloc);
                                return (IBT_INSUFF_RESOURCE);
                        }
                }

                /*
                 * Now check (and, if necessary, modify) the flags to indicate
                 * whether the allocation was successful
                 */
                mask = (1 << (TAVOR_SPECIAL_QP1_RSRC + port));
                if (flags & mask) {
                        mutex_exit(&state->ts_spec_qplock);
                        TNF_PROBE_0(tavor_ts_spec_qp1_alloc_already,
                            TAVOR_TNF_ERROR, "");
                        TAVOR_TNF_EXIT(tavor_special_qp_rsrc_alloc);
                        return (IBT_QP_IN_USE);
                }
                state->ts_spec_qpflags |= mask;
                *qp_rsrc = state->ts_spec_qp1;
        }

        mutex_exit(&state->ts_spec_qplock);
        TAVOR_TNF_EXIT(tavor_special_qp_rsrc_alloc);
        return (DDI_SUCCESS);
}


/*
 * tavor_special_qp_rsrc_free
 *    Context: Can be called from interrupt or base context.
 */
static int
tavor_special_qp_rsrc_free(tavor_state_t *state, ibt_sqp_type_t type,
    uint_t port)
{
        uint_t          mask, flags;
        int             status;

        TAVOR_TNF_ENTER(tavor_special_qp_rsrc_free);

        mutex_enter(&state->ts_spec_qplock);
        if (type == IBT_SMI_SQP) {
                mask = (1 << (TAVOR_SPECIAL_QP0_RSRC + port));
                state->ts_spec_qpflags &= ~mask;
                flags = state->ts_spec_qpflags;

                /*
                 * If this is the last QP0 free, then post a CONF_SPECIAL_QP
                 * firmware command
                 */
                if ((flags & TAVOR_SPECIAL_QP0_RSRC_MASK) == 0) {
                        status = tavor_conf_special_qp_cmd_post(state, 0,
                            TAVOR_CMD_QP_SMI, TAVOR_CMD_NOSLEEP_SPIN);
                        if (status != TAVOR_CMD_SUCCESS) {
                                mutex_exit(&state->ts_spec_qplock);
                                cmn_err(CE_CONT, "Tavor: CONF_SPECIAL_QP "
                                    "command failed: %08x\n", status);
                                TNF_PROBE_1(tavor_conf_special_qp_cmd_fail,
                                    TAVOR_TNF_ERROR, "", tnf_uint, status,
                                    status);
                                TAVOR_TNF_EXIT(tavor_special_qp_rsrc_free);
                                return (ibc_get_ci_failure(0));
                        }
                }
        } else {
                mask = (1 << (TAVOR_SPECIAL_QP1_RSRC + port));
                state->ts_spec_qpflags &= ~mask;
                flags = state->ts_spec_qpflags;

                /*
                 * If this is the last QP1 free, then post a CONF_SPECIAL_QP
                 * firmware command
                 */
                if ((flags & TAVOR_SPECIAL_QP1_RSRC_MASK) == 0) {
                        status = tavor_conf_special_qp_cmd_post(state, 0,
                            TAVOR_CMD_QP_GSI, TAVOR_CMD_NOSLEEP_SPIN);
                        if (status != TAVOR_CMD_SUCCESS) {
                                mutex_exit(&state->ts_spec_qplock);
                                cmn_err(CE_CONT, "Tavor: CONF_SPECIAL_QP "
                                    "command failed: %08x\n", status);
                                TNF_PROBE_1(tavor_conf_special_qp_cmd_fail,
                                    TAVOR_TNF_ERROR, "", tnf_uint, status,
                                    status);
                                TAVOR_TNF_EXIT(tavor_special_qp_rsrc_free);
                                return (ibc_get_ci_failure(0));
                        }
                }
        }

        mutex_exit(&state->ts_spec_qplock);
        TAVOR_TNF_EXIT(tavor_special_qp_rsrc_free);
        return (DDI_SUCCESS);
}


/*
 * tavor_qp_sgl_to_logwqesz()
 *    Context: Can be called from interrupt or base context.
 */
static void
tavor_qp_sgl_to_logwqesz(tavor_state_t *state, uint_t num_sgl,
    tavor_qp_wq_type_t wq_type, uint_t *logwqesz, uint_t *max_sgl)
{
        uint_t  max_size, log2, actual_sgl;

        TAVOR_TNF_ENTER(tavor_qp_sgl_to_logwqesz);

        switch (wq_type) {
        case TAVOR_QP_WQ_TYPE_SENDQ:
                /*
                 * Use requested maximum SGL to calculate max descriptor size
                 * (while guaranteeing that the descriptor size is a
                 * power-of-2 cachelines).
                 */
                max_size = (TAVOR_QP_WQE_MLX_SND_HDRS + (num_sgl << 4));
                log2 = highbit(max_size);
                if (ISP2(max_size)) {
                        log2 = log2 - 1;
                }

                /* Make sure descriptor is at least the minimum size */
                log2 = max(log2, TAVOR_QP_WQE_LOG_MINIMUM);

                /* Calculate actual number of SGL (given WQE size) */
                actual_sgl = ((1 << log2) - TAVOR_QP_WQE_MLX_SND_HDRS) >> 4;
                break;

        case TAVOR_QP_WQ_TYPE_RECVQ:
                /*
                 * Same as above (except for Recv WQEs)
                 */
                max_size = (TAVOR_QP_WQE_MLX_RCV_HDRS + (num_sgl << 4));
                log2 = highbit(max_size);
                if (ISP2(max_size)) {
                        log2 = log2 - 1;
                }

                /* Make sure descriptor is at least the minimum size */
                log2 = max(log2, TAVOR_QP_WQE_LOG_MINIMUM);

                /* Calculate actual number of SGL (given WQE size) */
                actual_sgl = ((1 << log2) - TAVOR_QP_WQE_MLX_RCV_HDRS) >> 4;
                break;

        case TAVOR_QP_WQ_TYPE_SENDMLX_QP0:
                /*
                 * Same as above (except for MLX transport WQEs).  For these
                 * WQEs we have to account for the space consumed by the
                 * "inline" packet headers.  (This is smaller than for QP1
                 * below because QP0 is not allowed to send packets with a GRH.
                 */
                max_size = (TAVOR_QP_WQE_MLX_QP0_HDRS + (num_sgl << 4));
                log2 = highbit(max_size);
                if (ISP2(max_size)) {
                        log2 = log2 - 1;
                }

                /* Make sure descriptor is at least the minimum size */
                log2 = max(log2, TAVOR_QP_WQE_LOG_MINIMUM);

                /* Calculate actual number of SGL (given WQE size) */
                actual_sgl = ((1 << log2) - TAVOR_QP_WQE_MLX_QP0_HDRS) >> 4;
                break;

        case TAVOR_QP_WQ_TYPE_SENDMLX_QP1:
                /*
                 * Same as above.  For these WQEs we again have to account for
                 * the space consumed by the "inline" packet headers.  (This
                 * is larger than for QP0 above because we have to account for
                 * the possibility of a GRH in each packet - and this
                 * introduces an alignment issue that causes us to consume
                 * an additional 8 bytes).
                 */
                max_size = (TAVOR_QP_WQE_MLX_QP1_HDRS + (num_sgl << 4));
                log2 = highbit(max_size);
                if (ISP2(max_size)) {
                        log2 = log2 - 1;
                }

                /* Make sure descriptor is at least the minimum size */
                log2 = max(log2, TAVOR_QP_WQE_LOG_MINIMUM);

                /* Calculate actual number of SGL (given WQE size) */
                actual_sgl = ((1 << log2) - TAVOR_QP_WQE_MLX_QP1_HDRS) >> 4;
                break;

        default:
                TAVOR_WARNING(state, "unexpected work queue type");
                TNF_PROBE_0(tavor_qp_sgl_to_logwqesz_inv_wqtype_fail,
                    TAVOR_TNF_ERROR, "");
                break;
        }

        /* Fill in the return values */
        *logwqesz = log2;
        *max_sgl  = min(state->ts_cfg_profile->cp_wqe_real_max_sgl, actual_sgl);

        TAVOR_TNF_EXIT(tavor_qp_sgl_to_logwqesz);
}