5255 uts shouldn't open-code ISP2

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26 
  27 /*
  28  * tavor_srq.c
  29  *    Tavor Shared Receive Queue Processing Routines
  30  *
  31  *    Implements all the routines necessary for allocating, freeing, querying,
  32  *    modifying and posting shared receive queues.
  33  */
  34 
  35 #include <sys/sysmacros.h>
  36 #include <sys/types.h>
  37 #include <sys/conf.h>
  38 #include <sys/ddi.h>
  39 #include <sys/sunddi.h>
  40 #include <sys/modctl.h>
  41 #include <sys/bitmap.h>
  42 
  43 #include <sys/ib/adapters/tavor/tavor.h>
  44 
  45 static void tavor_srq_sgl_to_logwqesz(tavor_state_t *state, uint_t num_sgl,
  46     tavor_qp_wq_type_t wq_type, uint_t *logwqesz, uint_t *max_sgl);
  47 
  48 /*
  49  * tavor_srq_alloc()
  50  *    Context: Can be called only from user or kernel context.
  51  */
  52 int
  53 tavor_srq_alloc(tavor_state_t *state, tavor_srq_info_t *srqinfo,
  54     uint_t sleepflag, tavor_srq_options_t *op)
  55 {
  56         ibt_srq_hdl_t           ibt_srqhdl;
  57         tavor_pdhdl_t           pd;
  58         ibt_srq_sizes_t         *sizes;
  59         ibt_srq_sizes_t         *real_sizes;
  60         tavor_srqhdl_t          *srqhdl;
  61         ibt_srq_flags_t         flags;
  62         tavor_rsrc_t            *srqc, *rsrc;
  63         tavor_hw_srqc_t         srqc_entry;
  64         uint32_t                *buf;
  65         tavor_srqhdl_t          srq;
  66         tavor_umap_db_entry_t   *umapdb;
  67         ibt_mr_attr_t           mr_attr;
  68         tavor_mr_options_t      mr_op;
  69         tavor_mrhdl_t           mr;
  70         uint64_t                addr;
  71         uint64_t                value, srq_desc_off;
  72         uint32_t                lkey;
  73         uint32_t                log_srq_size;
  74         uint32_t                uarpg;
  75         uint_t                  wq_location, dma_xfer_mode, srq_is_umap;
  76         int                     flag, status;
  77         char                    *errormsg;
  78         uint_t                  max_sgl;
  79         uint_t                  wqesz;
  80 
  81         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*sizes))
  82 
  83         TAVOR_TNF_ENTER(tavor_srq_alloc);
  84 
  85         /*
  86          * Check the "options" flag.  Currently this flag tells the driver
  87          * whether or not the SRQ's work queues should be come from normal
  88          * system memory or whether they should be allocated from DDR memory.
  89          */
  90         if (op == NULL) {
  91                 wq_location = TAVOR_QUEUE_LOCATION_NORMAL;
  92         } else {
  93                 wq_location = op->srqo_wq_loc;
  94         }
  95 
  96         /*
  97          * Extract the necessary info from the tavor_srq_info_t structure
  98          */
  99         real_sizes = srqinfo->srqi_real_sizes;
 100         sizes      = srqinfo->srqi_sizes;
 101         pd         = srqinfo->srqi_pd;
 102         ibt_srqhdl = srqinfo->srqi_ibt_srqhdl;
 103         flags      = srqinfo->srqi_flags;
 104         srqhdl     = srqinfo->srqi_srqhdl;
 105 
 106         /*
 107          * Determine whether SRQ is being allocated for userland access or
 108          * whether it is being allocated for kernel access.  If the SRQ is
 109          * being allocated for userland access, then lookup the UAR doorbell
 110          * page number for the current process.  Note:  If this is not found
 111          * (e.g. if the process has not previously open()'d the Tavor driver),
 112          * then an error is returned.
 113          */
 114         srq_is_umap = (flags & IBT_SRQ_USER_MAP) ? 1 : 0;
 115         if (srq_is_umap) {
 116                 status = tavor_umap_db_find(state->ts_instance, ddi_get_pid(),
 117                     MLNX_UMAP_UARPG_RSRC, &value, 0, NULL);
 118                 if (status != DDI_SUCCESS) {
 119                         /* Set "status" and "errormsg" and goto failure */
 120                         TAVOR_TNF_FAIL(IBT_INVALID_PARAM, "failed UAR page");
 121                         goto srqalloc_fail3;
 122                 }
 123                 uarpg = ((tavor_rsrc_t *)(uintptr_t)value)->tr_indx;
 124         }
 125 
 126         /* Increase PD refcnt */
 127         tavor_pd_refcnt_inc(pd);
 128 
 129         /* Allocate an SRQ context entry */
 130         status = tavor_rsrc_alloc(state, TAVOR_SRQC, 1, sleepflag, &srqc);
 131         if (status != DDI_SUCCESS) {
 132                 /* Set "status" and "errormsg" and goto failure */
 133                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed SRQ context");
 134                 goto srqalloc_fail1;
 135         }
 136 
 137         /* Allocate the SRQ Handle entry */
 138         status = tavor_rsrc_alloc(state, TAVOR_SRQHDL, 1, sleepflag, &rsrc);
 139         if (status != DDI_SUCCESS) {
 140                 /* Set "status" and "errormsg" and goto failure */
 141                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed SRQ handle");
 142                 goto srqalloc_fail2;
 143         }
 144 
 145         srq = (tavor_srqhdl_t)rsrc->tr_addr;
 146         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*srq))
 147 
 148         srq->srq_srqnum = srqc->tr_indx;  /* just use index */
 149 
 150         /*
 151          * If this will be a user-mappable SRQ, then allocate an entry for
 152          * the "userland resources database".  This will later be added to
 153          * the database (after all further SRQ operations are successful).
 154          * If we fail here, we must undo the reference counts and the
 155          * previous resource allocation.
 156          */
 157         if (srq_is_umap) {
 158                 umapdb = tavor_umap_db_alloc(state->ts_instance,
 159                     srq->srq_srqnum, MLNX_UMAP_SRQMEM_RSRC,
 160                     (uint64_t)(uintptr_t)rsrc);
 161                 if (umapdb == NULL) {
 162                         /* Set "status" and "errormsg" and goto failure */
 163                         TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed umap add");
 164                         goto srqalloc_fail3;
 165                 }
 166         }
 167 
 168         /*
 169          * Calculate the appropriate size for the SRQ.
 170          * Note:  All Tavor SRQs must be a power-of-2 in size.  Also
 171          * they may not be any smaller than TAVOR_SRQ_MIN_SIZE.  This step
 172          * is to round the requested size up to the next highest power-of-2
 173          */
 174         sizes->srq_wr_sz = max(sizes->srq_wr_sz, TAVOR_SRQ_MIN_SIZE);
 175         log_srq_size = highbit(sizes->srq_wr_sz);
 176         if (ISP2(sizes->srq_wr_sz)) {
 177                 log_srq_size = log_srq_size - 1;
 178         }
 179 
 180         /*
 181          * Next we verify that the rounded-up size is valid (i.e. consistent
 182          * with the device limits and/or software-configured limits).  If not,
 183          * then obviously we have a lot of cleanup to do before returning.
 184          */
 185         if (log_srq_size > state->ts_cfg_profile->cp_log_max_srq_sz) {
 186                 /* Set "status" and "errormsg" and goto failure */
 187                 TAVOR_TNF_FAIL(IBT_HCA_WR_EXCEEDED, "max SRQ size");
 188                 goto srqalloc_fail4;
 189         }
 190 
 191         /*
 192          * Next we verify that the requested number of SGL is valid (i.e.
 193          * consistent with the device limits and/or software-configured
 194          * limits).  If not, then obviously the same cleanup needs to be done.
 195          */
 196         max_sgl = state->ts_cfg_profile->cp_srq_max_sgl;
 197         if (sizes->srq_sgl_sz > max_sgl) {
 198                 /* Set "status" and "errormsg" and goto failure */
 199                 TAVOR_TNF_FAIL(IBT_HCA_SGL_EXCEEDED, "max SRQ SGL");
 200                 goto srqalloc_fail4;
 201         }
 202 
 203         /*
 204          * Determine the SRQ's WQE sizes.  This depends on the requested
 205          * number of SGLs.  Note: This also has the side-effect of
 206          * calculating the real number of SGLs (for the calculated WQE size)
 207          */
 208         tavor_srq_sgl_to_logwqesz(state, sizes->srq_sgl_sz,
 209             TAVOR_QP_WQ_TYPE_RECVQ, &srq->srq_wq_log_wqesz,
 210             &srq->srq_wq_sgl);
 211 
 212         /*
 213          * Allocate the memory for SRQ work queues.  Note:  The location from
 214          * which we will allocate these work queues has been passed in through
 215          * the tavor_qp_options_t structure.  Since Tavor work queues are not
 216          * allowed to cross a 32-bit (4GB) boundary, the alignment of the work
 217          * queue memory is very important.  We used to allocate work queues
 218          * (the combined receive and send queues) so that they would be aligned
 219          * on their combined size.  That alignment guaranteed that they would
 220          * never cross the 4GB boundary (Tavor work queues are on the order of
 221          * MBs at maximum).  Now we are able to relax this alignment constraint
 222          * by ensuring that the IB address assigned to the queue memory (as a
 223          * result of the tavor_mr_register() call) is offset from zero.
 224          * Previously, we had wanted to use the ddi_dma_mem_alloc() routine to
 225          * guarantee the alignment, but when attempting to use IOMMU bypass
 226          * mode we found that we were not allowed to specify any alignment that
 227          * was more restrictive than the system page size.  So we avoided this
 228          * constraint by passing two alignment values, one for the memory
 229          * allocation itself and the other for the DMA handle (for later bind).
 230          * This used to cause more memory than necessary to be allocated (in
 231          * order to guarantee the more restrictive alignment contraint).  But
 232          * be guaranteeing the zero-based IB virtual address for the queue, we
 233          * are able to conserve this memory.
 234          *
 235          * Note: If SRQ is not user-mappable, then it may come from either
 236          * kernel system memory or from HCA-attached local DDR memory.
 237          *
 238          * Note2: We align this queue on a pagesize boundary.  This is required
 239          * to make sure that all the resulting IB addresses will start at 0, for
 240          * a zero-based queue.  By making sure we are aligned on at least a
 241          * page, any offset we use into our queue will be the same as when we
 242          * perform tavor_srq_modify() operations later.
 243          */
 244         wqesz = (1 << srq->srq_wq_log_wqesz);
 245         srq->srq_wqinfo.qa_size = (1 << log_srq_size) * wqesz;
 246         srq->srq_wqinfo.qa_alloc_align = PAGESIZE;
 247         srq->srq_wqinfo.qa_bind_align = PAGESIZE;
 248         if (srq_is_umap) {
 249                 srq->srq_wqinfo.qa_location = TAVOR_QUEUE_LOCATION_USERLAND;
 250         } else {
 251                 srq->srq_wqinfo.qa_location = wq_location;
 252         }
 253         status = tavor_queue_alloc(state, &srq->srq_wqinfo, sleepflag);
 254         if (status != DDI_SUCCESS) {
 255                 /* Set "status" and "errormsg" and goto failure */
 256                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed srq");
 257                 goto srqalloc_fail4;
 258         }
 259         buf = (uint32_t *)srq->srq_wqinfo.qa_buf_aligned;
 260         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*buf))
 261 
 262         /*
 263          * Register the memory for the SRQ work queues.  The memory for the SRQ
 264          * must be registered in the Tavor TPT tables.  This gives us the LKey
 265          * to specify in the SRQ context later.  Note: If the work queue is to
 266          * be allocated from DDR memory, then only a "bypass" mapping is
 267          * appropriate.  And if the SRQ memory is user-mappable, then we force
 268          * DDI_DMA_CONSISTENT mapping.  Also, in order to meet the alignment
 269          * restriction, we pass the "mro_bind_override_addr" flag in the call
 270          * to tavor_mr_register().  This guarantees that the resulting IB vaddr
 271          * will be zero-based (modulo the offset into the first page).  If we
 272          * fail here, we still have the bunch of resource and reference count
 273          * cleanup to do.
 274          */
 275         flag = (sleepflag == TAVOR_SLEEP) ? IBT_MR_SLEEP :
 276             IBT_MR_NOSLEEP;
 277         mr_attr.mr_vaddr = (uint64_t)(uintptr_t)buf;
 278         mr_attr.mr_len   = srq->srq_wqinfo.qa_size;
 279         mr_attr.mr_as    = NULL;
 280         mr_attr.mr_flags = flag | IBT_MR_ENABLE_LOCAL_WRITE;
 281         if (srq_is_umap) {
 282                 mr_op.mro_bind_type   = state->ts_cfg_profile->cp_iommu_bypass;
 283         } else {
 284                 if (wq_location == TAVOR_QUEUE_LOCATION_NORMAL) {
 285                         mr_op.mro_bind_type =
 286                             state->ts_cfg_profile->cp_iommu_bypass;
 287                         dma_xfer_mode =
 288                             state->ts_cfg_profile->cp_streaming_consistent;
 289                         if (dma_xfer_mode == DDI_DMA_STREAMING) {
 290                                 mr_attr.mr_flags |= IBT_MR_NONCOHERENT;
 291                         }
 292                 } else {
 293                         mr_op.mro_bind_type = TAVOR_BINDMEM_BYPASS;
 294                 }
 295         }
 296         mr_op.mro_bind_dmahdl = srq->srq_wqinfo.qa_dmahdl;
 297         mr_op.mro_bind_override_addr = 1;
 298         status = tavor_mr_register(state, pd, &mr_attr, &mr, &mr_op);
 299         if (status != DDI_SUCCESS) {
 300                 /* Set "status" and "errormsg" and goto failure */
 301                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed register mr");
 302                 goto srqalloc_fail5;
 303         }
 304         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*mr))
 305         addr = mr->mr_bindinfo.bi_addr;
 306         lkey = mr->mr_lkey;
 307 
 308         /*
 309          * Calculate the offset between the kernel virtual address space
 310          * and the IB virtual address space.  This will be used when
 311          * posting work requests to properly initialize each WQE.
 312          */
 313         srq_desc_off = (uint64_t)(uintptr_t)srq->srq_wqinfo.qa_buf_aligned -
 314             (uint64_t)mr->mr_bindinfo.bi_addr;
 315 
 316         /*
 317          * Create WQL and Wridlist for use by this SRQ
 318          */
 319         srq->srq_wrid_wql = tavor_wrid_wql_create(state);
 320         if (srq->srq_wrid_wql == NULL) {
 321                 /* Set "status" and "errormsg" and goto failure */
 322                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed wql create");
 323                 goto srqalloc_fail6;
 324         }
 325         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*(srq->srq_wrid_wql)))
 326 
 327         srq->srq_wridlist = tavor_wrid_get_list(1 << log_srq_size);
 328         if (srq->srq_wridlist == NULL) {
 329                 /* Set "status" and "errormsg" and goto failure */
 330                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed wridlist create");
 331                 goto srqalloc_fail7;
 332         }
 333         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*(srq->srq_wridlist)))
 334 
 335         srq->srq_wridlist->wl_srq_en = 1;
 336         srq->srq_wridlist->wl_free_list_indx = -1;
 337 
 338         /*
 339          * Fill in all the return arguments (if necessary).  This includes
 340          * real queue size and real SGLs.
 341          */
 342         if (real_sizes != NULL) {
 343                 real_sizes->srq_wr_sz = (1 << log_srq_size);
 344                 real_sizes->srq_sgl_sz = srq->srq_wq_sgl;
 345         }
 346 
 347         /*
 348          * Fill in the SRQC entry.  This is the final step before passing
 349          * ownership of the SRQC entry to the Tavor hardware.  We use all of
 350          * the information collected/calculated above to fill in the
 351          * requisite portions of the SRQC.  Note: If this SRQ is going to be
 352          * used for userland access, then we need to set the UAR page number
 353          * appropriately (otherwise it's a "don't care")
 354          */
 355         bzero(&srqc_entry, sizeof (tavor_hw_srqc_t));
 356         srqc_entry.wqe_addr_h      = (addr >> 32);
 357         srqc_entry.next_wqe_addr_l = 0;
 358         srqc_entry.ds              = (wqesz >> 4);
 359         srqc_entry.state           = TAVOR_SRQ_STATE_HW_OWNER;
 360         srqc_entry.pd              = pd->pd_pdnum;
 361         srqc_entry.lkey            = lkey;
 362         srqc_entry.wqe_cnt         = 0;
 363         if (srq_is_umap) {
 364                 srqc_entry.uar     = uarpg;
 365         } else {
 366                 srqc_entry.uar     = 0;
 367         }
 368 
 369         /*
 370          * Write the SRQC entry to hardware.  Lastly, we pass ownership of
 371          * the entry to the hardware (using the Tavor SW2HW_SRQ firmware
 372          * command).  Note: In general, this operation shouldn't fail.  But
 373          * if it does, we have to undo everything we've done above before
 374          * returning error.
 375          */
 376         status = tavor_cmn_ownership_cmd_post(state, SW2HW_SRQ, &srqc_entry,
 377             sizeof (tavor_hw_srqc_t), srq->srq_srqnum,
 378             sleepflag);
 379         if (status != TAVOR_CMD_SUCCESS) {
 380                 cmn_err(CE_CONT, "Tavor: SW2HW_SRQ command failed: %08x\n",
 381                     status);
 382                 TNF_PROBE_1(tavor_srq_alloc_sw2hw_srq_cmd_fail,
 383                     TAVOR_TNF_ERROR, "", tnf_uint, status, status);
 384                 /* Set "status" and "errormsg" and goto failure */
 385                 TAVOR_TNF_FAIL(IBT_FAILURE, "tavor SW2HW_SRQ command");
 386                 goto srqalloc_fail8;
 387         }
 388 
 389         /*
 390          * Fill in the rest of the Tavor SRQ handle.  We can update
 391          * the following fields for use in further operations on the SRQ.
 392          */
 393         srq->srq_srqcrsrcp = srqc;
 394         srq->srq_rsrcp          = rsrc;
 395         srq->srq_mrhdl          = mr;
 396         srq->srq_refcnt         = 0;
 397         srq->srq_is_umap   = srq_is_umap;
 398         srq->srq_uarpg          = (srq->srq_is_umap) ? uarpg : 0;
 399         srq->srq_umap_dhp  = (devmap_cookie_t)NULL;
 400         srq->srq_pdhdl          = pd;
 401         srq->srq_wq_lastwqeindx = -1;
 402         srq->srq_wq_bufsz  = (1 << log_srq_size);
 403         srq->srq_wq_buf         = buf;
 404         srq->srq_desc_off  = srq_desc_off;
 405         srq->srq_hdlrarg   = (void *)ibt_srqhdl;
 406         srq->srq_state          = 0;
 407         srq->srq_real_sizes.srq_wr_sz = (1 << log_srq_size);
 408         srq->srq_real_sizes.srq_sgl_sz = srq->srq_wq_sgl;
 409 
 410         /* Determine if later ddi_dma_sync will be necessary */
 411         srq->srq_sync = TAVOR_SRQ_IS_SYNC_REQ(state, srq->srq_wqinfo);
 412 
 413         /*
 414          * Put SRQ handle in Tavor SRQNum-to-SRQhdl list.  Then fill in the
 415          * "srqhdl" and return success
 416          */
 417         ASSERT(state->ts_srqhdl[srqc->tr_indx] == NULL);
 418         state->ts_srqhdl[srqc->tr_indx] = srq;
 419 
 420         /*
 421          * If this is a user-mappable SRQ, then we need to insert the
 422          * previously allocated entry into the "userland resources database".
 423          * This will allow for later lookup during devmap() (i.e. mmap())
 424          * calls.
 425          */
 426         if (srq->srq_is_umap) {
 427                 tavor_umap_db_add(umapdb);
 428         } else {
 429                 mutex_enter(&srq->srq_wrid_wql->wql_lock);
 430                 tavor_wrid_list_srq_init(srq->srq_wridlist, srq, 0);
 431                 mutex_exit(&srq->srq_wrid_wql->wql_lock);
 432         }
 433 
 434         *srqhdl = srq;
 435 
 436         TAVOR_TNF_EXIT(tavor_srq_alloc);
 437         return (status);
 438 
 439 /*
 440  * The following is cleanup for all possible failure cases in this routine
 441  */
 442 srqalloc_fail8:
 443         kmem_free(srq->srq_wridlist->wl_wre, srq->srq_wridlist->wl_size *
 444             sizeof (tavor_wrid_entry_t));
 445         kmem_free(srq->srq_wridlist, sizeof (tavor_wrid_list_hdr_t));
 446 srqalloc_fail7:
 447         tavor_wql_refcnt_dec(srq->srq_wrid_wql);
 448 srqalloc_fail6:
 449         if (tavor_mr_deregister(state, &mr, TAVOR_MR_DEREG_ALL,
 450             TAVOR_SLEEPFLAG_FOR_CONTEXT()) != DDI_SUCCESS) {
 451                 TAVOR_WARNING(state, "failed to deregister SRQ memory");
 452         }
 453 srqalloc_fail5:
 454         tavor_queue_free(state, &srq->srq_wqinfo);
 455 srqalloc_fail4:
 456         if (srq_is_umap) {
 457                 tavor_umap_db_free(umapdb);
 458         }
 459 srqalloc_fail3:
 460         tavor_rsrc_free(state, &rsrc);
 461 srqalloc_fail2:
 462         tavor_rsrc_free(state, &srqc);
 463 srqalloc_fail1:
 464         tavor_pd_refcnt_dec(pd);
 465 srqalloc_fail:
 466         TNF_PROBE_1(tavor_srq_alloc_fail, TAVOR_TNF_ERROR, "",
 467             tnf_string, msg, errormsg);
 468         TAVOR_TNF_EXIT(tavor_srq_alloc);
 469         return (status);
 470 }
 471 
 472 
 473 /*
 474  * tavor_srq_free()
 475  *    Context: Can be called only from user or kernel context.
 476  */
 477 /* ARGSUSED */
 478 int
 479 tavor_srq_free(tavor_state_t *state, tavor_srqhdl_t *srqhdl, uint_t sleepflag)
 480 {
 481         tavor_rsrc_t            *srqc, *rsrc;
 482         tavor_umap_db_entry_t   *umapdb;
 483         uint64_t                value;
 484         tavor_srqhdl_t          srq;
 485         tavor_mrhdl_t           mr;
 486         tavor_pdhdl_t           pd;
 487         tavor_hw_srqc_t         srqc_entry;
 488         uint32_t                srqnum;
 489         uint32_t                size;
 490         uint_t                  maxprot;
 491         int                     status;
 492 
 493         TAVOR_TNF_ENTER(tavor_srq_free);
 494 
 495         /*
 496          * Pull all the necessary information from the Tavor Shared Receive
 497          * Queue handle.  This is necessary here because the resource for the
 498          * SRQ handle is going to be freed up as part of this operation.
 499          */
 500         srq     = *srqhdl;
 501         mutex_enter(&srq->srq_lock);
 502         srqc    = srq->srq_srqcrsrcp;
 503         rsrc    = srq->srq_rsrcp;
 504         pd      = srq->srq_pdhdl;
 505         mr      = srq->srq_mrhdl;
 506         srqnum  = srq->srq_srqnum;
 507 
 508         /*
 509          * If there are work queues still associated with the SRQ, then return
 510          * an error.  Otherwise, we will be holding the SRQ lock.
 511          */
 512         if (srq->srq_refcnt != 0) {
 513                 mutex_exit(&srq->srq_lock);
 514                 TNF_PROBE_1(tavor_srq_free_refcnt_fail, TAVOR_TNF_ERROR, "",
 515                     tnf_int, refcnt, srq->srq_refcnt);
 516                 TAVOR_TNF_EXIT(tavor_srq_free);
 517                 return (IBT_SRQ_IN_USE);
 518         }
 519 
 520         /*
 521          * If this was a user-mappable SRQ, then we need to remove its entry
 522          * from the "userland resources database".  If it is also currently
 523          * mmap()'d out to a user process, then we need to call
 524          * devmap_devmem_remap() to remap the SRQ memory to an invalid mapping.
 525          * We also need to invalidate the SRQ tracking information for the
 526          * user mapping.
 527          */
 528         if (srq->srq_is_umap) {
 529                 status = tavor_umap_db_find(state->ts_instance, srq->srq_srqnum,
 530                     MLNX_UMAP_SRQMEM_RSRC, &value, TAVOR_UMAP_DB_REMOVE,
 531                     &umapdb);
 532                 if (status != DDI_SUCCESS) {
 533                         mutex_exit(&srq->srq_lock);
 534                         TAVOR_WARNING(state, "failed to find in database");
 535                         TAVOR_TNF_EXIT(tavor_srq_free);
 536                         return (ibc_get_ci_failure(0));
 537                 }
 538                 tavor_umap_db_free(umapdb);
 539                 if (srq->srq_umap_dhp != NULL) {
 540                         maxprot = (PROT_READ | PROT_WRITE | PROT_USER);
 541                         status = devmap_devmem_remap(srq->srq_umap_dhp,
 542                             state->ts_dip, 0, 0, srq->srq_wqinfo.qa_size,
 543                             maxprot, DEVMAP_MAPPING_INVALID, NULL);
 544                         if (status != DDI_SUCCESS) {
 545                                 mutex_exit(&srq->srq_lock);
 546                                 TAVOR_WARNING(state, "failed in SRQ memory "
 547                                     "devmap_devmem_remap()");
 548                                 TAVOR_TNF_EXIT(tavor_srq_free);
 549                                 return (ibc_get_ci_failure(0));
 550                         }
 551                         srq->srq_umap_dhp = (devmap_cookie_t)NULL;
 552                 }
 553         }
 554 
 555         /*
 556          * Put NULL into the Tavor SRQNum-to-SRQHdl list.  This will allow any
 557          * in-progress events to detect that the SRQ corresponding to this
 558          * number has been freed.
 559          */
 560         state->ts_srqhdl[srqc->tr_indx] = NULL;
 561 
 562         mutex_exit(&srq->srq_lock);
 563         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*srq));
 564         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*srq->srq_wridlist));
 565 
 566         /*
 567          * Reclaim SRQC entry from hardware (using the Tavor HW2SW_SRQ
 568          * firmware command).  If the ownership transfer fails for any reason,
 569          * then it is an indication that something (either in HW or SW) has
 570          * gone seriously wrong.
 571          */
 572         status = tavor_cmn_ownership_cmd_post(state, HW2SW_SRQ, &srqc_entry,
 573             sizeof (tavor_hw_srqc_t), srqnum, sleepflag);
 574         if (status != TAVOR_CMD_SUCCESS) {
 575                 TAVOR_WARNING(state, "failed to reclaim SRQC ownership");
 576                 cmn_err(CE_CONT, "Tavor: HW2SW_SRQ command failed: %08x\n",
 577                     status);
 578                 TNF_PROBE_1(tavor_srq_free_hw2sw_srq_cmd_fail,
 579                     TAVOR_TNF_ERROR, "", tnf_uint, status, status);
 580                 TAVOR_TNF_EXIT(tavor_srq_free);
 581                 return (IBT_FAILURE);
 582         }
 583 
 584         /*
 585          * Deregister the memory for the Shared Receive Queue.  If this fails
 586          * for any reason, then it is an indication that something (either
 587          * in HW or SW) has gone seriously wrong.  So we print a warning
 588          * message and return.
 589          */
 590         status = tavor_mr_deregister(state, &mr, TAVOR_MR_DEREG_ALL,
 591             sleepflag);
 592         if (status != DDI_SUCCESS) {
 593                 TAVOR_WARNING(state, "failed to deregister SRQ memory");
 594                 TNF_PROBE_0(tavor_srq_free_dereg_mr_fail, TAVOR_TNF_ERROR, "");
 595                 TAVOR_TNF_EXIT(tavor_srq_free);
 596                 return (IBT_FAILURE);
 597         }
 598 
 599         /* Calculate the size and free the wridlist container */
 600         if (srq->srq_wridlist != NULL) {
 601                 size = (srq->srq_wridlist->wl_size *
 602                     sizeof (tavor_wrid_entry_t));
 603                 kmem_free(srq->srq_wridlist->wl_wre, size);
 604                 kmem_free(srq->srq_wridlist, sizeof (tavor_wrid_list_hdr_t));
 605 
 606                 /*
 607                  * Release reference to WQL; If this is the last reference,
 608                  * this call also has the side effect of freeing up the
 609                  * 'srq_wrid_wql' memory.
 610                  */
 611                 tavor_wql_refcnt_dec(srq->srq_wrid_wql);
 612         }
 613 
 614         /* Free the memory for the SRQ */
 615         tavor_queue_free(state, &srq->srq_wqinfo);
 616 
 617         /* Free the Tavor SRQ Handle */
 618         tavor_rsrc_free(state, &rsrc);
 619 
 620         /* Free the SRQC entry resource */
 621         tavor_rsrc_free(state, &srqc);
 622 
 623         /* Decrement the reference count on the protection domain (PD) */
 624         tavor_pd_refcnt_dec(pd);
 625 
 626         /* Set the srqhdl pointer to NULL and return success */
 627         *srqhdl = NULL;
 628 
 629         TAVOR_TNF_EXIT(tavor_srq_free);
 630         return (DDI_SUCCESS);
 631 }
 632 
 633 
 634 /*
 635  * tavor_srq_modify()
 636  *    Context: Can be called only from user or kernel context.
 637  */
 638 int
 639 tavor_srq_modify(tavor_state_t *state, tavor_srqhdl_t srq, uint_t size,
 640     uint_t *real_size, uint_t sleepflag)
 641 {
 642         tavor_qalloc_info_t     new_srqinfo, old_srqinfo;
 643         tavor_rsrc_t            *mtt, *mpt, *old_mtt;
 644         tavor_bind_info_t       bind;
 645         tavor_bind_info_t       old_bind;
 646         tavor_rsrc_pool_info_t  *rsrc_pool;
 647         tavor_mrhdl_t           mr;
 648         tavor_hw_mpt_t          mpt_entry;
 649         tavor_wrid_entry_t      *wre_new, *wre_old;
 650         uint64_t                mtt_ddrbaseaddr, mtt_addr;
 651         uint64_t                srq_desc_off;
 652         uint32_t                *buf, srq_old_bufsz;
 653         uint32_t                wqesz;
 654         uint_t                  max_srq_size;
 655         uint_t                  dma_xfer_mode, mtt_pgsize_bits;
 656         uint_t                  srq_sync, log_srq_size, maxprot;
 657         uint_t                  wq_location;
 658         int                     status;
 659         char                    *errormsg;
 660 
 661         TAVOR_TNF_ENTER(tavor_srq_modify);
 662 
 663         /*
 664          * Check the "inddr" flag.  This flag tells the driver whether or not
 665          * the SRQ's work queues should be come from normal system memory or
 666          * whether they should be allocated from DDR memory.
 667          */
 668         wq_location = state->ts_cfg_profile->cp_srq_wq_inddr;
 669 
 670         /*
 671          * If size requested is larger than device capability, return
 672          * Insufficient Resources
 673          */
 674         max_srq_size = (1 << state->ts_cfg_profile->cp_log_max_srq_sz);
 675         if (size > max_srq_size) {
 676                 TNF_PROBE_0(tavor_srq_modify_size_larger_than_maxsize,
 677                     TAVOR_TNF_ERROR, "");
 678                 TAVOR_TNF_EXIT(tavor_srq_modify);
 679                 return (IBT_HCA_WR_EXCEEDED);
 680         }
 681 
 682         /*
 683          * Calculate the appropriate size for the SRQ.
 684          * Note:  All Tavor SRQs must be a power-of-2 in size.  Also
 685          * they may not be any smaller than TAVOR_SRQ_MIN_SIZE.  This step
 686          * is to round the requested size up to the next highest power-of-2
 687          */
 688         size = max(size, TAVOR_SRQ_MIN_SIZE);
 689         log_srq_size = highbit(size);
 690         if (ISP2(size)) {
 691                 log_srq_size = log_srq_size - 1;
 692         }
 693 
 694         /*
 695          * Next we verify that the rounded-up size is valid (i.e. consistent
 696          * with the device limits and/or software-configured limits).
 697          */
 698         if (log_srq_size > state->ts_cfg_profile->cp_log_max_srq_sz) {
 699                 /* Set "status" and "errormsg" and goto failure */
 700                 TAVOR_TNF_FAIL(IBT_HCA_WR_EXCEEDED, "max SRQ size");
 701                 goto srqmodify_fail;
 702         }
 703 
 704         /*
 705          * Allocate the memory for newly resized Shared Receive Queue.
 706          *
 707          * Note: If SRQ is not user-mappable, then it may come from either
 708          * kernel system memory or from HCA-attached local DDR memory.
 709          *
 710          * Note2: We align this queue on a pagesize boundary.  This is required
 711          * to make sure that all the resulting IB addresses will start at 0,
 712          * for a zero-based queue.  By making sure we are aligned on at least a
 713          * page, any offset we use into our queue will be the same as it was
 714          * when we allocated it at tavor_srq_alloc() time.
 715          */
 716         wqesz = (1 << srq->srq_wq_log_wqesz);
 717         new_srqinfo.qa_size = (1 << log_srq_size) * wqesz;
 718         new_srqinfo.qa_alloc_align = PAGESIZE;
 719         new_srqinfo.qa_bind_align  = PAGESIZE;
 720         if (srq->srq_is_umap) {
 721                 new_srqinfo.qa_location = TAVOR_QUEUE_LOCATION_USERLAND;
 722         } else {
 723                 new_srqinfo.qa_location = wq_location;
 724         }
 725         status = tavor_queue_alloc(state, &new_srqinfo, sleepflag);
 726         if (status != DDI_SUCCESS) {
 727                 /* Set "status" and "errormsg" and goto failure */
 728                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE, "failed srq");
 729                 goto srqmodify_fail;
 730         }
 731         buf = (uint32_t *)new_srqinfo.qa_buf_aligned;
 732         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*buf))
 733 
 734         /*
 735          * Allocate the memory for the new WRE list.  This will be used later
 736          * when we resize the wridlist based on the new SRQ size.
 737          */
 738         wre_new = (tavor_wrid_entry_t *)kmem_zalloc((1 << log_srq_size) *
 739             sizeof (tavor_wrid_entry_t), sleepflag);
 740         if (wre_new == NULL) {
 741                 /* Set "status" and "errormsg" and goto failure */
 742                 TAVOR_TNF_FAIL(IBT_INSUFF_RESOURCE,
 743                     "failed wre_new alloc");
 744                 goto srqmodify_fail;
 745         }
 746 
 747         /*
 748          * Fill in the "bind" struct.  This struct provides the majority
 749          * of the information that will be used to distinguish between an
 750          * "addr" binding (as is the case here) and a "buf" binding (see
 751          * below).  The "bind" struct is later passed to tavor_mr_mem_bind()
 752          * which does most of the "heavy lifting" for the Tavor memory
 753          * registration routines.
 754          */
 755         _NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(bind))
 756         bzero(&bind, sizeof (tavor_bind_info_t));
 757         bind.bi_type  = TAVOR_BINDHDL_VADDR;
 758         bind.bi_addr  = (uint64_t)(uintptr_t)buf;
 759         bind.bi_len   = new_srqinfo.qa_size;
 760         bind.bi_as    = NULL;
 761         bind.bi_flags = sleepflag == TAVOR_SLEEP ? IBT_MR_SLEEP :
 762             IBT_MR_NOSLEEP | IBT_MR_ENABLE_LOCAL_WRITE;
 763         if (srq->srq_is_umap) {
 764                 bind.bi_bypass = state->ts_cfg_profile->cp_iommu_bypass;
 765         } else {
 766                 if (wq_location == TAVOR_QUEUE_LOCATION_NORMAL) {
 767                         bind.bi_bypass =
 768                             state->ts_cfg_profile->cp_iommu_bypass;
 769                         dma_xfer_mode =
 770                             state->ts_cfg_profile->cp_streaming_consistent;
 771                         if (dma_xfer_mode == DDI_DMA_STREAMING) {
 772                                 bind.bi_flags |= IBT_MR_NONCOHERENT;
 773                         }
 774                 } else {
 775                         bind.bi_bypass = TAVOR_BINDMEM_BYPASS;
 776                 }
 777         }
 778         status = tavor_mr_mtt_bind(state, &bind, new_srqinfo.qa_dmahdl, &mtt,
 779             &mtt_pgsize_bits);
 780         if (status != DDI_SUCCESS) {
 781                 /* Set "status" and "errormsg" and goto failure */
 782                 TAVOR_TNF_FAIL(status, "failed mtt bind");
 783                 kmem_free(wre_new, srq->srq_wq_bufsz *
 784                     sizeof (tavor_wrid_entry_t));
 785                 tavor_queue_free(state, &new_srqinfo);
 786                 goto srqmodify_fail;
 787         }
 788 
 789         /*
 790          * Calculate the offset between the kernel virtual address space
 791          * and the IB virtual address space.  This will be used when
 792          * posting work requests to properly initialize each WQE.
 793          *
 794          * Note: bind addr is zero-based (from alloc) so we calculate the
 795          * correct new offset here.
 796          */
 797         bind.bi_addr = bind.bi_addr & ((1 << mtt_pgsize_bits) - 1);
 798         srq_desc_off = (uint64_t)(uintptr_t)new_srqinfo.qa_buf_aligned -
 799             (uint64_t)bind.bi_addr;
 800 
 801         /*
 802          * Get the base address for the MTT table.  This will be necessary
 803          * below when we are modifying the MPT entry.
 804          */
 805         rsrc_pool = &state->ts_rsrc_hdl[TAVOR_MTT];
 806         mtt_ddrbaseaddr = (uint64_t)(uintptr_t)rsrc_pool->rsrc_ddr_offset;
 807 
 808         /*
 809          * Fill in the MPT entry.  This is the final step before passing
 810          * ownership of the MPT entry to the Tavor hardware.  We use all of
 811          * the information collected/calculated above to fill in the
 812          * requisite portions of the MPT.
 813          */
 814         bzero(&mpt_entry, sizeof (tavor_hw_mpt_t));
 815         mpt_entry.reg_win_len   = bind.bi_len;
 816         mtt_addr = mtt_ddrbaseaddr + (mtt->tr_indx << TAVOR_MTT_SIZE_SHIFT);
 817         mpt_entry.mttseg_addr_h = mtt_addr >> 32;
 818         mpt_entry.mttseg_addr_l = mtt_addr >> 6;
 819 
 820         /*
 821          * Now we grab the SRQ lock.  Since we will be updating the actual
 822          * SRQ location and the producer/consumer indexes, we should hold
 823          * the lock.
 824          *
 825          * We do a TAVOR_NOSLEEP here (and below), though, because we are
 826          * holding the "srq_lock" and if we got raised to interrupt level
 827          * by priority inversion, we would not want to block in this routine
 828          * waiting for success.
 829          */
 830         mutex_enter(&srq->srq_lock);
 831 
 832         /*
 833          * Copy old entries to new buffer
 834          */
 835         srq_old_bufsz = srq->srq_wq_bufsz;
 836         bcopy(srq->srq_wq_buf, buf, srq_old_bufsz * wqesz);
 837 
 838         /* Determine if later ddi_dma_sync will be necessary */
 839         srq_sync = TAVOR_SRQ_IS_SYNC_REQ(state, srq->srq_wqinfo);
 840 
 841         /* Sync entire "new" SRQ for use by hardware (if necessary) */
 842         if (srq_sync) {
 843                 (void) ddi_dma_sync(bind.bi_dmahdl, 0,
 844                     new_srqinfo.qa_size, DDI_DMA_SYNC_FORDEV);
 845         }
 846 
 847         /*
 848          * Setup MPT information for use in the MODIFY_MPT command
 849          */
 850         mr = srq->srq_mrhdl;
 851         mutex_enter(&mr->mr_lock);
 852         mpt = srq->srq_mrhdl->mr_mptrsrcp;
 853 
 854         /*
 855          * MODIFY_MPT
 856          *
 857          * If this fails for any reason, then it is an indication that
 858          * something (either in HW or SW) has gone seriously wrong.  So we
 859          * print a warning message and return.
 860          */
 861         status = tavor_modify_mpt_cmd_post(state, &mpt_entry, mpt->tr_indx,
 862             TAVOR_CMD_MODIFY_MPT_RESIZESRQ, sleepflag);
 863         if (status != TAVOR_CMD_SUCCESS) {
 864                 cmn_err(CE_CONT, "Tavor: MODIFY_MPT command failed: %08x\n",
 865                     status);
 866                 TNF_PROBE_1(tavor_mr_common_reg_sw2hw_mpt_cmd_fail,
 867                     TAVOR_TNF_ERROR, "", tnf_uint, status, status);
 868                 TAVOR_TNF_FAIL(status, "MODIFY_MPT command failed");
 869                 (void) tavor_mr_mtt_unbind(state, &srq->srq_mrhdl->mr_bindinfo,
 870                     srq->srq_mrhdl->mr_mttrsrcp);
 871                 kmem_free(wre_new, srq->srq_wq_bufsz *
 872                     sizeof (tavor_wrid_entry_t));
 873                 tavor_queue_free(state, &new_srqinfo);
 874                 mutex_exit(&mr->mr_lock);
 875                 mutex_exit(&srq->srq_lock);
 876                 return (ibc_get_ci_failure(0));
 877         }
 878 
 879         /*
 880          * Update the Tavor Shared Receive Queue handle with all the new
 881          * information.  At the same time, save away all the necessary
 882          * information for freeing up the old resources
 883          */
 884         old_srqinfo        = srq->srq_wqinfo;
 885         old_mtt            = srq->srq_mrhdl->mr_mttrsrcp;
 886         bcopy(&srq->srq_mrhdl->mr_bindinfo, &old_bind,
 887             sizeof (tavor_bind_info_t));
 888 
 889         /* Now set the new info */
 890         srq->srq_wqinfo         = new_srqinfo;
 891         srq->srq_wq_buf         = buf;
 892         srq->srq_wq_bufsz  = (1 << log_srq_size);
 893         bcopy(&bind, &srq->srq_mrhdl->mr_bindinfo, sizeof (tavor_bind_info_t));
 894         srq->srq_mrhdl->mr_mttrsrcp = mtt;
 895         srq->srq_desc_off  = srq_desc_off;
 896         srq->srq_real_sizes.srq_wr_sz = (1 << log_srq_size);
 897 
 898         /* Update MR mtt pagesize */
 899         mr->mr_logmttpgsz = mtt_pgsize_bits;
 900         mutex_exit(&mr->mr_lock);
 901 
 902 #ifdef __lock_lint
 903         mutex_enter(&srq->srq_wrid_wql->wql_lock);
 904 #else
 905         if (srq->srq_wrid_wql != NULL) {
 906                 mutex_enter(&srq->srq_wrid_wql->wql_lock);
 907         }
 908 #endif
 909 
 910         /*
 911          * Initialize new wridlist, if needed.
 912          *
 913          * If a wridlist already is setup on an SRQ (the QP associated with an
 914          * SRQ has moved "from_reset") then we must update this wridlist based
 915          * on the new SRQ size.  We allocate the new size of Work Request ID
 916          * Entries, copy over the old entries to the new list, and
 917          * re-initialize the srq wridlist in non-umap case
 918          */
 919         wre_old = NULL;
 920         if (srq->srq_wridlist != NULL) {
 921                 wre_old = srq->srq_wridlist->wl_wre;
 922 
 923                 bcopy(wre_old, wre_new, srq_old_bufsz *
 924                     sizeof (tavor_wrid_entry_t));
 925 
 926                 /* Setup new sizes in wre */
 927                 srq->srq_wridlist->wl_wre = wre_new;
 928                 srq->srq_wridlist->wl_size = srq->srq_wq_bufsz;
 929 
 930                 if (!srq->srq_is_umap) {
 931                         tavor_wrid_list_srq_init(srq->srq_wridlist, srq,
 932                             srq_old_bufsz);
 933                 }
 934         }
 935 
 936 #ifdef __lock_lint
 937         mutex_exit(&srq->srq_wrid_wql->wql_lock);
 938 #else
 939         if (srq->srq_wrid_wql != NULL) {
 940                 mutex_exit(&srq->srq_wrid_wql->wql_lock);
 941         }
 942 #endif
 943 
 944         /*
 945          * If "old" SRQ was a user-mappable SRQ that is currently mmap()'d out
 946          * to a user process, then we need to call devmap_devmem_remap() to
 947          * invalidate the mapping to the SRQ memory.  We also need to
 948          * invalidate the SRQ tracking information for the user mapping.
 949          *
 950          * Note: On failure, the remap really shouldn't ever happen.  So, if it
 951          * does, it is an indication that something has gone seriously wrong.
 952          * So we print a warning message and return error (knowing, of course,
 953          * that the "old" SRQ memory will be leaked)
 954          */
 955         if ((srq->srq_is_umap) && (srq->srq_umap_dhp != NULL)) {
 956                 maxprot = (PROT_READ | PROT_WRITE | PROT_USER);
 957                 status = devmap_devmem_remap(srq->srq_umap_dhp,
 958                     state->ts_dip, 0, 0, srq->srq_wqinfo.qa_size, maxprot,
 959                     DEVMAP_MAPPING_INVALID, NULL);
 960                 if (status != DDI_SUCCESS) {
 961                         mutex_exit(&srq->srq_lock);
 962                         TAVOR_WARNING(state, "failed in SRQ memory "
 963                             "devmap_devmem_remap()");
 964                         /* We can, however, free the memory for old wre */
 965                         if (wre_old != NULL) {
 966                                 kmem_free(wre_old, srq_old_bufsz *
 967                                     sizeof (tavor_wrid_entry_t));
 968                         }
 969                         TAVOR_TNF_EXIT(tavor_srq_modify);
 970                         return (ibc_get_ci_failure(0));
 971                 }
 972                 srq->srq_umap_dhp = (devmap_cookie_t)NULL;
 973         }
 974 
 975         /*
 976          * Drop the SRQ lock now.  The only thing left to do is to free up
 977          * the old resources.
 978          */
 979         mutex_exit(&srq->srq_lock);
 980 
 981         /*
 982          * Unbind the MTT entries.
 983          */
 984         status = tavor_mr_mtt_unbind(state, &old_bind, old_mtt);
 985         if (status != DDI_SUCCESS) {
 986                 TAVOR_WARNING(state, "failed to unbind old SRQ memory");
 987                 /* Set "status" and "errormsg" and goto failure */
 988                 TAVOR_TNF_FAIL(ibc_get_ci_failure(0),
 989                     "failed to unbind (old)");
 990                 goto srqmodify_fail;
 991         }
 992 
 993         /* Free the memory for old wre */
 994         if (wre_old != NULL) {
 995                 kmem_free(wre_old, srq_old_bufsz *
 996                     sizeof (tavor_wrid_entry_t));
 997         }
 998 
 999         /* Free the memory for the old SRQ */
1000         tavor_queue_free(state, &old_srqinfo);
1001 
1002         /*
1003          * Fill in the return arguments (if necessary).  This includes the
1004          * real new completion queue size.
1005          */
1006         if (real_size != NULL) {
1007                 *real_size = (1 << log_srq_size);
1008         }
1009 
1010         TAVOR_TNF_EXIT(tavor_srq_modify);
1011         return (DDI_SUCCESS);
1012 
1013 srqmodify_fail:
1014         TNF_PROBE_1(tavor_srq_modify_fail, TAVOR_TNF_ERROR, "",
1015             tnf_string, msg, errormsg);
1016         TAVOR_TNF_EXIT(tavor_srq_modify);
1017         return (status);
1018 }
1019 
1020 
1021 /*
1022  * tavor_srq_refcnt_inc()
1023  *    Context: Can be called from interrupt or base context.
1024  */
1025 void
1026 tavor_srq_refcnt_inc(tavor_srqhdl_t srq)
1027 {
1028         mutex_enter(&srq->srq_lock);
1029         TNF_PROBE_1_DEBUG(tavor_srq_refcnt_inc, TAVOR_TNF_TRACE, "",
1030             tnf_uint, refcnt, srq->srq_refcnt);
1031         srq->srq_refcnt++;
1032         mutex_exit(&srq->srq_lock);
1033 }
1034 
1035 
1036 /*
1037  * tavor_srq_refcnt_dec()
1038  *    Context: Can be called from interrupt or base context.
1039  */
1040 void
1041 tavor_srq_refcnt_dec(tavor_srqhdl_t srq)
1042 {
1043         mutex_enter(&srq->srq_lock);
1044         srq->srq_refcnt--;
1045         TNF_PROBE_1_DEBUG(tavor_srq_refcnt_dec, TAVOR_TNF_TRACE, "",
1046             tnf_uint, refcnt, srq->srq_refcnt);
1047         mutex_exit(&srq->srq_lock);
1048 }
1049 
1050 
1051 /*
1052  * tavor_srqhdl_from_srqnum()
1053  *    Context: Can be called from interrupt or base context.
1054  *
1055  *    This routine is important because changing the unconstrained
1056  *    portion of the SRQ number is critical to the detection of a
1057  *    potential race condition in the SRQ handler code (i.e. the case
1058  *    where a SRQ is freed and alloc'd again before an event for the
1059  *    "old" SRQ can be handled).
1060  *
1061  *    While this is not a perfect solution (not sure that one exists)
1062  *    it does help to mitigate the chance that this race condition will
1063  *    cause us to deliver a "stale" event to the new SRQ owner.  Note:
1064  *    this solution does not scale well because the number of constrained
1065  *    bits increases (and, hence, the number of unconstrained bits
1066  *    decreases) as the number of supported SRQ grows.  For small and
1067  *    intermediate values, it should hopefully provide sufficient
1068  *    protection.
1069  */
1070 tavor_srqhdl_t
1071 tavor_srqhdl_from_srqnum(tavor_state_t *state, uint_t srqnum)
1072 {
1073         uint_t  srqindx, srqmask;
1074 
1075         /* Calculate the SRQ table index from the srqnum */
1076         srqmask = (1 << state->ts_cfg_profile->cp_log_num_srq) - 1;
1077         srqindx = srqnum & srqmask;
1078         return (state->ts_srqhdl[srqindx]);
1079 }
1080 
1081 
1082 /*
1083  * tavor_srq_sgl_to_logwqesz()
1084  *    Context: Can be called from interrupt or base context.
1085  */
1086 static void
1087 tavor_srq_sgl_to_logwqesz(tavor_state_t *state, uint_t num_sgl,
1088     tavor_qp_wq_type_t wq_type, uint_t *logwqesz, uint_t *max_sgl)
1089 {
1090         uint_t  max_size, log2, actual_sgl;
1091 
1092         TAVOR_TNF_ENTER(tavor_srq_sgl_to_logwqesz);
1093 
1094         switch (wq_type) {
1095         case TAVOR_QP_WQ_TYPE_RECVQ:
1096                 /*
1097                  * Use requested maximum SGL to calculate max descriptor size
1098                  * (while guaranteeing that the descriptor size is a
1099                  * power-of-2 cachelines).
1100                  */
1101                 max_size = (TAVOR_QP_WQE_MLX_RCV_HDRS + (num_sgl << 4));
1102                 log2 = highbit(max_size);
1103                 if (ISP2(max_size)) {
1104                         log2 = log2 - 1;
1105                 }
1106 
1107                 /* Make sure descriptor is at least the minimum size */
1108                 log2 = max(log2, TAVOR_QP_WQE_LOG_MINIMUM);
1109 
1110                 /* Calculate actual number of SGL (given WQE size) */
1111                 actual_sgl = ((1 << log2) - TAVOR_QP_WQE_MLX_RCV_HDRS) >> 4;
1112                 break;
1113 
1114         default:
1115                 TAVOR_WARNING(state, "unexpected work queue type");
1116                 TNF_PROBE_0(tavor_srq_sgl_to_logwqesz_inv_wqtype_fail,
1117                     TAVOR_TNF_ERROR, "");
1118                 break;
1119         }
1120 
1121         /* Fill in the return values */
1122         *logwqesz = log2;
1123         *max_sgl  = min(state->ts_cfg_profile->cp_srq_max_sgl, actual_sgl);
1124 
1125         TAVOR_TNF_EXIT(tavor_qp_sgl_to_logwqesz);
1126 }
--- EOF ---