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   1 /*
   2  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  *
  32  * $Id: iser_initiator.c 6964 2006-05-07 11:11:43Z ogerlitz $
  33  */
  34 #include <linux/kernel.h>
  35 #include <linux/slab.h>
  36 #include <linux/mm.h>
  37 #include <asm/io.h>
  38 #include <asm/scatterlist.h>
  39 #include <linux/scatterlist.h>
  40 #include <linux/kfifo.h>
  41 #include <scsi/scsi_cmnd.h>
  42 #include <scsi/scsi_host.h>
  43
  44 #include "iscsi_iser.h"
  45
  46 /* Constant PDU lengths calculations */
  47 #define ISER_TOTAL_HEADERS_LEN  (sizeof (struct iser_hdr) + \
  48                                  sizeof (struct iscsi_hdr))
  49
  50 /* iser_dto_add_regd_buff - increments the reference count for *
  51  * the registered buffer & adds it to the DTO object           */
  52 static void iser_dto_add_regd_buff(struct iser_dto *dto,
  53                                    struct iser_regd_buf *regd_buf,
  54                                    unsigned long use_offset,
  55                                    unsigned long use_size)
  56 {
  57         int add_idx;
  58
  59         atomic_inc(&regd_buf->ref_count);
  60
  61         add_idx = dto->regd_vector_len;
  62         dto->regd[add_idx] = regd_buf;
  63         dto->used_sz[add_idx] = use_size;
  64         dto->offset[add_idx] = use_offset;
  65
  66         dto->regd_vector_len++;
  67 }
  68
  69 /* Register user buffer memory and initialize passive rdma
  70  *  dto descriptor. Total data size is stored in
  71  *  iser_ctask->data[ISER_DIR_IN].data_len
  72  */
  73 static int iser_prepare_read_cmd(struct iscsi_cmd_task *ctask,
  74                                  unsigned int edtl)
  75
  76 {
  77         struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
  78         struct iser_regd_buf *regd_buf;
  79         int err;
  80         struct iser_hdr *hdr = &iser_ctask->desc.iser_header;
  81         struct iser_data_buf *buf_in = &iser_ctask->data[ISER_DIR_IN];
  82
  83         err = iser_dma_map_task_data(iser_ctask,
  84                                      buf_in,
  85                                      ISER_DIR_IN,
  86                                      DMA_FROM_DEVICE);
  87         if (err)
  88                 return err;
  89
  90         if (edtl > iser_ctask->data[ISER_DIR_IN].data_len) {
  91                 iser_err("Total data length: %ld, less than EDTL: "
  92                          "%d, in READ cmd BHS itt: %d, conn: 0x%p\n",
  93                          iser_ctask->data[ISER_DIR_IN].data_len, edtl,
  94                          ctask->itt, iser_ctask->iser_conn);
  95                 return -EINVAL;
  96         }
  97
  98         err = iser_reg_rdma_mem(iser_ctask,ISER_DIR_IN);
  99         if (err) {
 100                 iser_err("Failed to set up Data-IN RDMA\n");
 101                 return err;
 102         }
 103         regd_buf = &iser_ctask->rdma_regd[ISER_DIR_IN];
 104
 105         hdr->flags    |= ISER_RSV;
 106         hdr->read_stag = cpu_to_be32(regd_buf->reg.rkey);
 107         hdr->read_va   = cpu_to_be64(regd_buf->reg.va);
 108
 109         iser_dbg("Cmd itt:%d READ tags RKEY:%#.4X VA:%#llX\n",
 110                  ctask->itt, regd_buf->reg.rkey,
 111                  (unsigned long long)regd_buf->reg.va);
 112
 113         return 0;
 114 }
 115
 116 /* Register user buffer memory and initialize passive rdma
 117  *  dto descriptor. Total data size is stored in
 118  *  ctask->data[ISER_DIR_OUT].data_len
 119  */
 120 static int
 121 iser_prepare_write_cmd(struct iscsi_cmd_task *ctask,
 122                        unsigned int imm_sz,
 123                        unsigned int unsol_sz,
 124                        unsigned int edtl)
 125 {
 126         struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
 127         struct iser_regd_buf *regd_buf;
 128         int err;
 129         struct iser_dto *send_dto = &iser_ctask->desc.dto;
 130         struct iser_hdr *hdr = &iser_ctask->desc.iser_header;
 131         struct iser_data_buf *buf_out = &iser_ctask->data[ISER_DIR_OUT];
 132
 133         err = iser_dma_map_task_data(iser_ctask,
 134                                      buf_out,
 135                                      ISER_DIR_OUT,
 136                                      DMA_TO_DEVICE);
 137         if (err)
 138                 return err;
 139
 140         if (edtl > iser_ctask->data[ISER_DIR_OUT].data_len) {
 141                 iser_err("Total data length: %ld, less than EDTL: %d, "
 142                          "in WRITE cmd BHS itt: %d, conn: 0x%p\n",
 143                          iser_ctask->data[ISER_DIR_OUT].data_len,
 144                          edtl, ctask->itt, ctask->conn);
 145                 return -EINVAL;
 146         }
 147
 148         err = iser_reg_rdma_mem(iser_ctask,ISER_DIR_OUT);
 149         if (err != 0) {
 150                 iser_err("Failed to register write cmd RDMA mem\n");
 151                 return err;
 152         }
 153
 154         regd_buf = &iser_ctask->rdma_regd[ISER_DIR_OUT];
 155
 156         if (unsol_sz < edtl) {
 157                 hdr->flags     |= ISER_WSV;
 158                 hdr->write_stag = cpu_to_be32(regd_buf->reg.rkey);
 159                 hdr->write_va   = cpu_to_be64(regd_buf->reg.va + unsol_sz);
 160
 161                 iser_dbg("Cmd itt:%d, WRITE tags, RKEY:%#.4X "
 162                          "VA:%#llX + unsol:%d\n",
 163                          ctask->itt, regd_buf->reg.rkey,
 164                          (unsigned long long)regd_buf->reg.va, unsol_sz);
 165         }
 166
 167         if (imm_sz > 0) {
 168                 iser_dbg("Cmd itt:%d, WRITE, adding imm.data sz: %d\n",
 169                          ctask->itt, imm_sz);
 170                 iser_dto_add_regd_buff(send_dto,
 171                                        regd_buf,
 172                                        0,
 173                                        imm_sz);
 174         }
 175
 176         return 0;
 177 }
 178
 179 /**
 180  * iser_post_receive_control - allocates, initializes and posts receive DTO.
 181  */
 182 static int iser_post_receive_control(struct iscsi_conn *conn)
 183 {
 184         struct iscsi_iser_conn *iser_conn = conn->dd_data;
 185         struct iser_desc     *rx_desc;
 186         struct iser_regd_buf *regd_hdr;
 187         struct iser_regd_buf *regd_data;
 188         struct iser_dto      *recv_dto = NULL;
 189         struct iser_device  *device = iser_conn->ib_conn->device;
 190         int rx_data_size, err = 0;
 191
 192         rx_desc = kmem_cache_alloc(ig.desc_cache, GFP_NOIO);
 193         if (rx_desc == NULL) {
 194                 iser_err("Failed to alloc desc for post recv\n");
 195                 return -ENOMEM;
 196         }
 197         rx_desc->type = ISCSI_RX;
 198
 199         /* for the login sequence we must support rx of upto 8K; login is done
 200          * after conn create/bind (connect) and conn stop/bind (reconnect),
 201          * what's common for both schemes is that the connection is not started
 202          */
 203         if (conn->c_stage != ISCSI_CONN_STARTED)
 204                 rx_data_size = ISCSI_DEF_MAX_RECV_SEG_LEN;
 205         else /* FIXME till user space sets conn->max_recv_dlength correctly */
 206                 rx_data_size = 128;
 207
 208         rx_desc->data = kmalloc(rx_data_size, GFP_NOIO);
 209         if (rx_desc->data == NULL) {
 210                 iser_err("Failed to alloc data buf for post recv\n");
 211                 err = -ENOMEM;
 212                 goto post_rx_kmalloc_failure;
 213         }
 214
 215         recv_dto = &rx_desc->dto;
 216         recv_dto->ib_conn = iser_conn->ib_conn;
 217         recv_dto->regd_vector_len = 0;
 218
 219         regd_hdr = &rx_desc->hdr_regd_buf;
 220         memset(regd_hdr, 0, sizeof(struct iser_regd_buf));
 221         regd_hdr->device  = device;
 222         regd_hdr->virt_addr  = rx_desc; /* == &rx_desc->iser_header */
 223         regd_hdr->data_size  = ISER_TOTAL_HEADERS_LEN;
 224
 225         iser_reg_single(device, regd_hdr, DMA_FROM_DEVICE);
 226
 227         iser_dto_add_regd_buff(recv_dto, regd_hdr, 0, 0);
 228
 229         regd_data = &rx_desc->data_regd_buf;
 230         memset(regd_data, 0, sizeof(struct iser_regd_buf));
 231         regd_data->device  = device;
 232         regd_data->virt_addr  = rx_desc->data;
 233         regd_data->data_size  = rx_data_size;
 234
 235         iser_reg_single(device, regd_data, DMA_FROM_DEVICE);
 236
 237         iser_dto_add_regd_buff(recv_dto, regd_data, 0, 0);
 238
 239         err = iser_post_recv(rx_desc);
 240         if (!err)
 241                 return 0;
 242
 243         /* iser_post_recv failed */
 244         iser_dto_buffs_release(recv_dto);
 245         kfree(rx_desc->data);
 246 post_rx_kmalloc_failure:
 247         kmem_cache_free(ig.desc_cache, rx_desc);
 248         return err;
 249 }
 250
 251 /* creates a new tx descriptor and adds header regd buffer */
 252 static void iser_create_send_desc(struct iscsi_iser_conn *iser_conn,
 253                                   struct iser_desc       *tx_desc)
 254 {
 255         struct iser_regd_buf *regd_hdr = &tx_desc->hdr_regd_buf;
 256         struct iser_dto      *send_dto = &tx_desc->dto;
 257
 258         memset(regd_hdr, 0, sizeof(struct iser_regd_buf));
 259         regd_hdr->device  = iser_conn->ib_conn->device;
 260         regd_hdr->virt_addr  = tx_desc; /* == &tx_desc->iser_header */
 261         regd_hdr->data_size  = ISER_TOTAL_HEADERS_LEN;
 262
 263         send_dto->ib_conn         = iser_conn->ib_conn;
 264         send_dto->notify_enable   = 1;
 265         send_dto->regd_vector_len = 0;
 266
 267         memset(&tx_desc->iser_header, 0, sizeof(struct iser_hdr));
 268         tx_desc->iser_header.flags = ISER_VER;
 269
 270         iser_dto_add_regd_buff(send_dto, regd_hdr, 0, 0);
 271 }
 272
 273 /**
 274  *  iser_conn_set_full_featured_mode - (iSER API)
 275  */
 276 int iser_conn_set_full_featured_mode(struct iscsi_conn *conn)
 277 {
 278         struct iscsi_iser_conn *iser_conn = conn->dd_data;
 279
 280         int i;
 281         /* no need to keep it in a var, we are after login so if this should
 282          * be negotiated, by now the result should be available here */
 283         int initial_post_recv_bufs_num = ISER_MAX_RX_MISC_PDUS;
 284
 285         iser_dbg("Initially post: %d\n", initial_post_recv_bufs_num);
 286
 287         /* Check that there is no posted recv or send buffers left - */
 288         /* they must be consumed during the login phase */
 289         BUG_ON(atomic_read(&iser_conn->ib_conn->post_recv_buf_count) != 0);
 290         BUG_ON(atomic_read(&iser_conn->ib_conn->post_send_buf_count) != 0);
 291
 292         /* Initial post receive buffers */
 293         for (i = 0; i < initial_post_recv_bufs_num; i++) {
 294                 if (iser_post_receive_control(conn) != 0) {
 295                         iser_err("Failed to post recv bufs at:%d conn:0x%p\n",
 296                                  i, conn);
 297                         return -ENOMEM;
 298                 }
 299         }
 300         iser_dbg("Posted %d post recv bufs, conn:0x%p\n", i, conn);
 301         return 0;
 302 }
 303
 304 static int
 305 iser_check_xmit(struct iscsi_conn *conn, void *task)
 306 {
 307         struct iscsi_iser_conn *iser_conn = conn->dd_data;
 308
 309         if (atomic_read(&iser_conn->ib_conn->post_send_buf_count) ==
 310             ISER_QP_MAX_REQ_DTOS) {
 311                 iser_dbg("%ld can't xmit task %p\n",jiffies,task);
 312                 return -ENOBUFS;
 313         }
 314         return 0;
 315 }
 316
 317
 318 /**
 319  * iser_send_command - send command PDU
 320  */
 321 int iser_send_command(struct iscsi_conn     *conn,
 322                       struct iscsi_cmd_task *ctask)
 323 {
 324         struct iscsi_iser_conn *iser_conn = conn->dd_data;
 325         struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
 326         struct iser_dto *send_dto = NULL;
 327         unsigned long edtl;
 328         int err = 0;
 329         struct iser_data_buf *data_buf;
 330
 331         struct iscsi_cmd *hdr =  ctask->hdr;
 332         struct scsi_cmnd *sc  =  ctask->sc;
 333
 334         if (!iser_conn_state_comp(iser_conn->ib_conn, ISER_CONN_UP)) {
 335                 iser_err("Failed to send, conn: 0x%p is not up\n", iser_conn->ib_conn);
 336                 return -EPERM;
 337         }
 338         if (iser_check_xmit(conn, ctask))
 339                 return -ENOBUFS;
 340
 341         edtl = ntohl(hdr->data_length);
 342
 343         /* build the tx desc regd header and add it to the tx desc dto */
 344         iser_ctask->desc.type = ISCSI_TX_SCSI_COMMAND;
 345         send_dto = &iser_ctask->desc.dto;
 346         send_dto->ctask = iser_ctask;
 347         iser_create_send_desc(iser_conn, &iser_ctask->desc);
 348
 349         if (hdr->flags & ISCSI_FLAG_CMD_READ)
 350                 data_buf = &iser_ctask->data[ISER_DIR_IN];
 351         else
 352                 data_buf = &iser_ctask->data[ISER_DIR_OUT];
 353
 354         if (scsi_sg_count(sc)) { /* using a scatter list */
 355                 data_buf->buf  = scsi_sglist(sc);
 356                 data_buf->size = scsi_sg_count(sc);
 357         }
 358
 359         data_buf->data_len = scsi_bufflen(sc);
 360
 361         if (hdr->flags & ISCSI_FLAG_CMD_READ) {
 362                 err = iser_prepare_read_cmd(ctask, edtl);
 363                 if (err)
 364                         goto send_command_error;
 365         }
 366         if (hdr->flags & ISCSI_FLAG_CMD_WRITE) {
 367                 err = iser_prepare_write_cmd(ctask,
 368                                              ctask->imm_count,
 369                                              ctask->imm_count +
 370                                              ctask->unsol_count,
 371                                              edtl);
 372                 if (err)
 373                         goto send_command_error;
 374         }
 375
 376         iser_reg_single(iser_conn->ib_conn->device,
 377                         send_dto->regd[0], DMA_TO_DEVICE);
 378
 379         if (iser_post_receive_control(conn) != 0) {
 380                 iser_err("post_recv failed!\n");
 381                 err = -ENOMEM;
 382                 goto send_command_error;
 383         }
 384
 385         iser_ctask->status = ISER_TASK_STATUS_STARTED;
 386
 387         err = iser_post_send(&iser_ctask->desc);
 388         if (!err)
 389                 return 0;
 390
 391 send_command_error:
 392         iser_dto_buffs_release(send_dto);
 393         iser_err("conn %p failed ctask->itt %d err %d\n",conn, ctask->itt, err);
 394         return err;
 395 }
 396
 397 /**
 398  * iser_send_data_out - send data out PDU
 399  */
 400 int iser_send_data_out(struct iscsi_conn     *conn,
 401                        struct iscsi_cmd_task *ctask,
 402                        struct iscsi_data *hdr)
 403 {
 404         struct iscsi_iser_conn *iser_conn = conn->dd_data;
 405         struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
 406         struct iser_desc *tx_desc = NULL;
 407         struct iser_dto *send_dto = NULL;
 408         unsigned long buf_offset;
 409         unsigned long data_seg_len;
 410         unsigned int itt;
 411         int err = 0;
 412
 413         if (!iser_conn_state_comp(iser_conn->ib_conn, ISER_CONN_UP)) {
 414                 iser_err("Failed to send, conn: 0x%p is not up\n", iser_conn->ib_conn);
 415                 return -EPERM;
 416         }
 417
 418         if (iser_check_xmit(conn, ctask))
 419                 return -ENOBUFS;
 420
 421         itt = ntohl(hdr->itt);
 422         data_seg_len = ntoh24(hdr->dlength);
 423         buf_offset   = ntohl(hdr->offset);
 424
 425         iser_dbg("%s itt %d dseg_len %d offset %d\n",
 426                  __func__,(int)itt,(int)data_seg_len,(int)buf_offset);
 427
 428         tx_desc = kmem_cache_alloc(ig.desc_cache, GFP_NOIO);
 429         if (tx_desc == NULL) {
 430                 iser_err("Failed to alloc desc for post dataout\n");
 431                 return -ENOMEM;
 432         }
 433
 434         tx_desc->type = ISCSI_TX_DATAOUT;
 435         memcpy(&tx_desc->iscsi_header, hdr, sizeof(struct iscsi_hdr));
 436
 437         /* build the tx desc regd header and add it to the tx desc dto */
 438         send_dto = &tx_desc->dto;
 439         send_dto->ctask = iser_ctask;
 440         iser_create_send_desc(iser_conn, tx_desc);
 441
 442         iser_reg_single(iser_conn->ib_conn->device,
 443                         send_dto->regd[0], DMA_TO_DEVICE);
 444
 445         /* all data was registered for RDMA, we can use the lkey */
 446         iser_dto_add_regd_buff(send_dto,
 447                                &iser_ctask->rdma_regd[ISER_DIR_OUT],
 448                                buf_offset,
 449                                data_seg_len);
 450
 451         if (buf_offset + data_seg_len > iser_ctask->data[ISER_DIR_OUT].data_len) {
 452                 iser_err("Offset:%ld & DSL:%ld in Data-Out "
 453                          "inconsistent with total len:%ld, itt:%d\n",
 454                          buf_offset, data_seg_len,
 455                          iser_ctask->data[ISER_DIR_OUT].data_len, itt);
 456                 err = -EINVAL;
 457                 goto send_data_out_error;
 458         }
 459         iser_dbg("data-out itt: %d, offset: %ld, sz: %ld\n",
 460                  itt, buf_offset, data_seg_len);
 461
 462
 463         err = iser_post_send(tx_desc);
 464         if (!err)
 465                 return 0;
 466
 467 send_data_out_error:
 468         iser_dto_buffs_release(send_dto);
 469         kmem_cache_free(ig.desc_cache, tx_desc);
 470         iser_err("conn %p failed err %d\n",conn, err);
 471         return err;
 472 }
 473
 474 int iser_send_control(struct iscsi_conn *conn,
 475                       struct iscsi_mgmt_task *mtask)
 476 {
 477         struct iscsi_iser_conn *iser_conn = conn->dd_data;
 478         struct iser_desc *mdesc = mtask->dd_data;
 479         struct iser_dto *send_dto = NULL;
 480         unsigned long data_seg_len;
 481         int err = 0;
 482         struct iser_regd_buf *regd_buf;
 483         struct iser_device *device;
 484
 485         if (!iser_conn_state_comp(iser_conn->ib_conn, ISER_CONN_UP)) {
 486                 iser_err("Failed to send, conn: 0x%p is not up\n", iser_conn->ib_conn);
 487                 return -EPERM;
 488         }
 489
 490         if (iser_check_xmit(conn,mtask))
 491                 return -ENOBUFS;
 492
 493         /* build the tx desc regd header and add it to the tx desc dto */
 494         mdesc->type = ISCSI_TX_CONTROL;
 495         send_dto = &mdesc->dto;
 496         send_dto->ctask = NULL;
 497         iser_create_send_desc(iser_conn, mdesc);
 498
 499         device = iser_conn->ib_conn->device;
 500
 501         iser_reg_single(device, send_dto->regd[0], DMA_TO_DEVICE);
 502
 503         data_seg_len = ntoh24(mtask->hdr->dlength);
 504
 505         if (data_seg_len > 0) {
 506                 regd_buf = &mdesc->data_regd_buf;
 507                 memset(regd_buf, 0, sizeof(struct iser_regd_buf));
 508                 regd_buf->device = device;
 509                 regd_buf->virt_addr = mtask->data;
 510                 regd_buf->data_size = mtask->data_count;
 511                 iser_reg_single(device, regd_buf,
 512                                 DMA_TO_DEVICE);
 513                 iser_dto_add_regd_buff(send_dto, regd_buf,
 514                                        0,
 515                                        data_seg_len);
 516         }
 517
 518         if (iser_post_receive_control(conn) != 0) {
 519                 iser_err("post_rcv_buff failed!\n");
 520                 err = -ENOMEM;
 521                 goto send_control_error;
 522         }
 523
 524         err = iser_post_send(mdesc);
 525         if (!err)
 526                 return 0;
 527
 528 send_control_error:
 529         iser_dto_buffs_release(send_dto);
 530         iser_err("conn %p failed err %d\n",conn, err);
 531         return err;
 532 }
 533
 534 /**
 535  * iser_rcv_dto_completion - recv DTO completion
 536  */
 537 void iser_rcv_completion(struct iser_desc *rx_desc,
 538                          unsigned long dto_xfer_len)
 539 {
 540         struct iser_dto        *dto = &rx_desc->dto;
 541         struct iscsi_iser_conn *conn = dto->ib_conn->iser_conn;
 542         struct iscsi_session *session = conn->iscsi_conn->session;
 543         struct iscsi_cmd_task *ctask;
 544         struct iscsi_iser_cmd_task *iser_ctask;
 545         struct iscsi_hdr *hdr;
 546         char   *rx_data = NULL;
 547         int     rx_data_len = 0;
 548         unsigned int itt;
 549         unsigned char opcode;
 550
 551         hdr = &rx_desc->iscsi_header;
 552
 553         iser_dbg("op 0x%x itt 0x%x\n", hdr->opcode,hdr->itt);
 554
 555         if (dto_xfer_len > ISER_TOTAL_HEADERS_LEN) { /* we have data */
 556                 rx_data_len = dto_xfer_len - ISER_TOTAL_HEADERS_LEN;
 557                 rx_data     = dto->regd[1]->virt_addr;
 558                 rx_data    += dto->offset[1];
 559         }
 560
 561         opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 562
 563         if (opcode == ISCSI_OP_SCSI_CMD_RSP) {
 564                 itt = get_itt(hdr->itt); /* mask out cid and age bits */
 565                 if (!(itt < session->cmds_max))
 566                         iser_err("itt can't be matched to task!!!"
 567                                  "conn %p opcode %d cmds_max %d itt %d\n",
 568                                  conn->iscsi_conn,opcode,session->cmds_max,itt);
 569                 /* use the mapping given with the cmds array indexed by itt */
 570                 ctask = (struct iscsi_cmd_task *)session->cmds[itt];
 571                 iser_ctask = ctask->dd_data;
 572                 iser_dbg("itt %d ctask %p\n",itt,ctask);
 573                 iser_ctask->status = ISER_TASK_STATUS_COMPLETED;
 574                 iser_ctask_rdma_finalize(iser_ctask);
 575         }
 576
 577         iser_dto_buffs_release(dto);
 578
 579         iscsi_iser_recv(conn->iscsi_conn, hdr, rx_data, rx_data_len);
 580
 581         kfree(rx_desc->data);
 582         kmem_cache_free(ig.desc_cache, rx_desc);
 583
 584         /* decrementing conn->post_recv_buf_count only --after-- freeing the   *
 585          * task eliminates the need to worry on tasks which are completed in   *
 586          * parallel to the execution of iser_conn_term. So the code that waits *
 587          * for the posted rx bufs refcount to become zero handles everything   */
 588         atomic_dec(&conn->ib_conn->post_recv_buf_count);
 589 }
 590
 591 void iser_snd_completion(struct iser_desc *tx_desc)
 592 {
 593         struct iser_dto        *dto = &tx_desc->dto;
 594         struct iser_conn       *ib_conn = dto->ib_conn;
 595         struct iscsi_iser_conn *iser_conn = ib_conn->iser_conn;
 596         struct iscsi_conn      *conn = iser_conn->iscsi_conn;
 597         struct iscsi_mgmt_task *mtask;
 598         int resume_tx = 0;
 599
 600         iser_dbg("Initiator, Data sent dto=0x%p\n", dto);
 601
 602         iser_dto_buffs_release(dto);
 603
 604         if (tx_desc->type == ISCSI_TX_DATAOUT)
 605                 kmem_cache_free(ig.desc_cache, tx_desc);
 606
 607         if (atomic_read(&iser_conn->ib_conn->post_send_buf_count) ==
 608             ISER_QP_MAX_REQ_DTOS)
 609                 resume_tx = 1;
 610
 611         atomic_dec(&ib_conn->post_send_buf_count);
 612
 613         if (resume_tx) {
 614                 iser_dbg("%ld resuming tx\n",jiffies);
 615                 scsi_queue_work(conn->session->host, &conn->xmitwork);
 616         }
 617
 618         if (tx_desc->type == ISCSI_TX_CONTROL) {
 619                 /* this arithmetic is legal by libiscsi dd_data allocation */
 620                 mtask = (void *) ((long)(void *)tx_desc -
 621                                   sizeof(struct iscsi_mgmt_task));
 622                 if (mtask->hdr->itt == RESERVED_ITT) {
 623                         struct iscsi_session *session = conn->session;
 624
 625                         spin_lock(&conn->session->lock);
 626                         list_del(&mtask->running);
 627                         __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
 628                                     sizeof(void*));
 629                         spin_unlock(&session->lock);
 630                 }
 631         }
 632 }
 633
 634 void iser_ctask_rdma_init(struct iscsi_iser_cmd_task *iser_ctask)
 635
 636 {
 637         iser_ctask->status = ISER_TASK_STATUS_INIT;
 638
 639         iser_ctask->dir[ISER_DIR_IN] = 0;
 640         iser_ctask->dir[ISER_DIR_OUT] = 0;
 641
 642         iser_ctask->data[ISER_DIR_IN].data_len  = 0;
 643         iser_ctask->data[ISER_DIR_OUT].data_len = 0;
 644
 645         memset(&iser_ctask->rdma_regd[ISER_DIR_IN], 0,
 646                sizeof(struct iser_regd_buf));
 647         memset(&iser_ctask->rdma_regd[ISER_DIR_OUT], 0,
 648                sizeof(struct iser_regd_buf));
 649 }
 650
 651 void iser_ctask_rdma_finalize(struct iscsi_iser_cmd_task *iser_ctask)
 652 {
 653         int deferred;
 654         int is_rdma_aligned = 1;
 655         struct iser_regd_buf *regd;
 656
 657         /* if we were reading, copy back to unaligned sglist,
 658          * anyway dma_unmap and free the copy
 659          */
 660         if (iser_ctask->data_copy[ISER_DIR_IN].copy_buf != NULL) {
 661                 is_rdma_aligned = 0;
 662                 iser_finalize_rdma_unaligned_sg(iser_ctask, ISER_DIR_IN);
 663         }
 664         if (iser_ctask->data_copy[ISER_DIR_OUT].copy_buf != NULL) {
 665                 is_rdma_aligned = 0;
 666                 iser_finalize_rdma_unaligned_sg(iser_ctask, ISER_DIR_OUT);
 667         }
 668
 669         if (iser_ctask->dir[ISER_DIR_IN]) {
 670                 regd = &iser_ctask->rdma_regd[ISER_DIR_IN];
 671                 deferred = iser_regd_buff_release(regd);
 672                 if (deferred) {
 673                         iser_err("%d references remain for BUF-IN rdma reg\n",
 674                                  atomic_read(&regd->ref_count));
 675                 }
 676         }
 677
 678         if (iser_ctask->dir[ISER_DIR_OUT]) {
 679                 regd = &iser_ctask->rdma_regd[ISER_DIR_OUT];
 680                 deferred = iser_regd_buff_release(regd);
 681                 if (deferred) {
 682                         iser_err("%d references remain for BUF-OUT rdma reg\n",
 683                                  atomic_read(&regd->ref_count));
 684                 }
 685         }
 686
 687        /* if the data was unaligned, it was already unmapped and then copied */
 688        if (is_rdma_aligned)
 689                 iser_dma_unmap_task_data(iser_ctask);
 690 }
 691
 692 void iser_dto_buffs_release(struct iser_dto *dto)
 693 {
 694         int i;
 695
 696         for (i = 0; i < dto->regd_vector_len; i++)
 697                 iser_regd_buff_release(dto->regd[i]);
 698 }
 699