linux/drivers/infiniband/ulp/iser/iser_initiator.c
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   1/*
   2 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
   3 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
   4 *
   5 * This software is available to you under a choice of one of two
   6 * licenses.  You may choose to be licensed under the terms of the GNU
   7 * General Public License (GPL) Version 2, available from the file
   8 * COPYING in the main directory of this source tree, or the
   9 * OpenIB.org BSD license below:
  10 *
  11 *     Redistribution and use in source and binary forms, with or
  12 *     without modification, are permitted provided that the following
  13 *     conditions are met:
  14 *
  15 *      - Redistributions of source code must retain the above
  16 *        copyright notice, this list of conditions and the following
  17 *        disclaimer.
  18 *
  19 *      - Redistributions in binary form must reproduce the above
  20 *        copyright notice, this list of conditions and the following
  21 *        disclaimer in the documentation and/or other materials
  22 *        provided with the distribution.
  23 *
  24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31 * SOFTWARE.
  32 */
  33#include <linux/kernel.h>
  34#include <linux/slab.h>
  35#include <linux/mm.h>
  36#include <linux/scatterlist.h>
  37#include <linux/kfifo.h>
  38#include <scsi/scsi_cmnd.h>
  39#include <scsi/scsi_host.h>
  40
  41#include "iscsi_iser.h"
  42
  43/* Register user buffer memory and initialize passive rdma
  44 *  dto descriptor. Data size is stored in
  45 *  task->data[ISER_DIR_IN].data_len, Protection size
  46 *  os stored in task->prot[ISER_DIR_IN].data_len
  47 */
  48static int iser_prepare_read_cmd(struct iscsi_task *task)
  49
  50{
  51        struct iscsi_iser_task *iser_task = task->dd_data;
  52        struct iser_mem_reg *mem_reg;
  53        int err;
  54        struct iser_ctrl *hdr = &iser_task->desc.iser_header;
  55        struct iser_data_buf *buf_in = &iser_task->data[ISER_DIR_IN];
  56
  57        err = iser_dma_map_task_data(iser_task,
  58                                     buf_in,
  59                                     ISER_DIR_IN,
  60                                     DMA_FROM_DEVICE);
  61        if (err)
  62                return err;
  63
  64        if (scsi_prot_sg_count(iser_task->sc)) {
  65                struct iser_data_buf *pbuf_in = &iser_task->prot[ISER_DIR_IN];
  66
  67                err = iser_dma_map_task_data(iser_task,
  68                                             pbuf_in,
  69                                             ISER_DIR_IN,
  70                                             DMA_FROM_DEVICE);
  71                if (err)
  72                        return err;
  73        }
  74
  75        err = iser_reg_rdma_mem(iser_task, ISER_DIR_IN, false);
  76        if (err) {
  77                iser_err("Failed to set up Data-IN RDMA\n");
  78                return err;
  79        }
  80        mem_reg = &iser_task->rdma_reg[ISER_DIR_IN];
  81
  82        hdr->flags    |= ISER_RSV;
  83        hdr->read_stag = cpu_to_be32(mem_reg->rkey);
  84        hdr->read_va   = cpu_to_be64(mem_reg->sge.addr);
  85
  86        iser_dbg("Cmd itt:%d READ tags RKEY:%#.4X VA:%#llX\n",
  87                 task->itt, mem_reg->rkey,
  88                 (unsigned long long)mem_reg->sge.addr);
  89
  90        return 0;
  91}
  92
  93/* Register user buffer memory and initialize passive rdma
  94 *  dto descriptor. Data size is stored in
  95 *  task->data[ISER_DIR_OUT].data_len, Protection size
  96 *  is stored at task->prot[ISER_DIR_OUT].data_len
  97 */
  98static int
  99iser_prepare_write_cmd(struct iscsi_task *task,
 100                       unsigned int imm_sz,
 101                       unsigned int unsol_sz,
 102                       unsigned int edtl)
 103{
 104        struct iscsi_iser_task *iser_task = task->dd_data;
 105        struct iser_mem_reg *mem_reg;
 106        int err;
 107        struct iser_ctrl *hdr = &iser_task->desc.iser_header;
 108        struct iser_data_buf *buf_out = &iser_task->data[ISER_DIR_OUT];
 109        struct ib_sge *tx_dsg = &iser_task->desc.tx_sg[1];
 110
 111        err = iser_dma_map_task_data(iser_task,
 112                                     buf_out,
 113                                     ISER_DIR_OUT,
 114                                     DMA_TO_DEVICE);
 115        if (err)
 116                return err;
 117
 118        if (scsi_prot_sg_count(iser_task->sc)) {
 119                struct iser_data_buf *pbuf_out = &iser_task->prot[ISER_DIR_OUT];
 120
 121                err = iser_dma_map_task_data(iser_task,
 122                                             pbuf_out,
 123                                             ISER_DIR_OUT,
 124                                             DMA_TO_DEVICE);
 125                if (err)
 126                        return err;
 127        }
 128
 129        err = iser_reg_rdma_mem(iser_task, ISER_DIR_OUT,
 130                                buf_out->data_len == imm_sz);
 131        if (err != 0) {
 132                iser_err("Failed to register write cmd RDMA mem\n");
 133                return err;
 134        }
 135
 136        mem_reg = &iser_task->rdma_reg[ISER_DIR_OUT];
 137
 138        if (unsol_sz < edtl) {
 139                hdr->flags     |= ISER_WSV;
 140                hdr->write_stag = cpu_to_be32(mem_reg->rkey);
 141                hdr->write_va   = cpu_to_be64(mem_reg->sge.addr + unsol_sz);
 142
 143                iser_dbg("Cmd itt:%d, WRITE tags, RKEY:%#.4X "
 144                         "VA:%#llX + unsol:%d\n",
 145                         task->itt, mem_reg->rkey,
 146                         (unsigned long long)mem_reg->sge.addr, unsol_sz);
 147        }
 148
 149        if (imm_sz > 0) {
 150                iser_dbg("Cmd itt:%d, WRITE, adding imm.data sz: %d\n",
 151                         task->itt, imm_sz);
 152                tx_dsg->addr = mem_reg->sge.addr;
 153                tx_dsg->length = imm_sz;
 154                tx_dsg->lkey = mem_reg->sge.lkey;
 155                iser_task->desc.num_sge = 2;
 156        }
 157
 158        return 0;
 159}
 160
 161/* creates a new tx descriptor and adds header regd buffer */
 162static void iser_create_send_desc(struct iser_conn      *iser_conn,
 163                                  struct iser_tx_desc   *tx_desc)
 164{
 165        struct iser_device *device = iser_conn->ib_conn.device;
 166
 167        ib_dma_sync_single_for_cpu(device->ib_device,
 168                tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
 169
 170        memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
 171        tx_desc->iser_header.flags = ISER_VER;
 172        tx_desc->num_sge = 1;
 173}
 174
 175static void iser_free_login_buf(struct iser_conn *iser_conn)
 176{
 177        struct iser_device *device = iser_conn->ib_conn.device;
 178        struct iser_login_desc *desc = &iser_conn->login_desc;
 179
 180        if (!desc->req)
 181                return;
 182
 183        ib_dma_unmap_single(device->ib_device, desc->req_dma,
 184                            ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);
 185
 186        ib_dma_unmap_single(device->ib_device, desc->rsp_dma,
 187                            ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);
 188
 189        kfree(desc->req);
 190        kfree(desc->rsp);
 191
 192        /* make sure we never redo any unmapping */
 193        desc->req = NULL;
 194        desc->rsp = NULL;
 195}
 196
 197static int iser_alloc_login_buf(struct iser_conn *iser_conn)
 198{
 199        struct iser_device *device = iser_conn->ib_conn.device;
 200        struct iser_login_desc *desc = &iser_conn->login_desc;
 201
 202        desc->req = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
 203        if (!desc->req)
 204                return -ENOMEM;
 205
 206        desc->req_dma = ib_dma_map_single(device->ib_device, desc->req,
 207                                          ISCSI_DEF_MAX_RECV_SEG_LEN,
 208                                          DMA_TO_DEVICE);
 209        if (ib_dma_mapping_error(device->ib_device,
 210                                desc->req_dma))
 211                goto free_req;
 212
 213        desc->rsp = kmalloc(ISER_RX_LOGIN_SIZE, GFP_KERNEL);
 214        if (!desc->rsp)
 215                goto unmap_req;
 216
 217        desc->rsp_dma = ib_dma_map_single(device->ib_device, desc->rsp,
 218                                           ISER_RX_LOGIN_SIZE,
 219                                           DMA_FROM_DEVICE);
 220        if (ib_dma_mapping_error(device->ib_device,
 221                                desc->rsp_dma))
 222                goto free_rsp;
 223
 224        return 0;
 225
 226free_rsp:
 227        kfree(desc->rsp);
 228unmap_req:
 229        ib_dma_unmap_single(device->ib_device, desc->req_dma,
 230                            ISCSI_DEF_MAX_RECV_SEG_LEN,
 231                            DMA_TO_DEVICE);
 232free_req:
 233        kfree(desc->req);
 234
 235        return -ENOMEM;
 236}
 237
 238int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
 239                              struct iscsi_session *session)
 240{
 241        int i, j;
 242        u64 dma_addr;
 243        struct iser_rx_desc *rx_desc;
 244        struct ib_sge       *rx_sg;
 245        struct ib_conn *ib_conn = &iser_conn->ib_conn;
 246        struct iser_device *device = ib_conn->device;
 247
 248        iser_conn->qp_max_recv_dtos = session->cmds_max;
 249        iser_conn->qp_max_recv_dtos_mask = session->cmds_max - 1; /* cmds_max is 2^N */
 250        iser_conn->min_posted_rx = iser_conn->qp_max_recv_dtos >> 2;
 251
 252        if (device->reg_ops->alloc_reg_res(ib_conn, session->scsi_cmds_max,
 253                                           iser_conn->scsi_sg_tablesize))
 254                goto create_rdma_reg_res_failed;
 255
 256        if (iser_alloc_login_buf(iser_conn))
 257                goto alloc_login_buf_fail;
 258
 259        iser_conn->num_rx_descs = session->cmds_max;
 260        iser_conn->rx_descs = kmalloc(iser_conn->num_rx_descs *
 261                                sizeof(struct iser_rx_desc), GFP_KERNEL);
 262        if (!iser_conn->rx_descs)
 263                goto rx_desc_alloc_fail;
 264
 265        rx_desc = iser_conn->rx_descs;
 266
 267        for (i = 0; i < iser_conn->qp_max_recv_dtos; i++, rx_desc++)  {
 268                dma_addr = ib_dma_map_single(device->ib_device, (void *)rx_desc,
 269                                        ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 270                if (ib_dma_mapping_error(device->ib_device, dma_addr))
 271                        goto rx_desc_dma_map_failed;
 272
 273                rx_desc->dma_addr = dma_addr;
 274                rx_desc->cqe.done = iser_task_rsp;
 275                rx_sg = &rx_desc->rx_sg;
 276                rx_sg->addr = rx_desc->dma_addr;
 277                rx_sg->length = ISER_RX_PAYLOAD_SIZE;
 278                rx_sg->lkey = device->pd->local_dma_lkey;
 279        }
 280
 281        iser_conn->rx_desc_head = 0;
 282        return 0;
 283
 284rx_desc_dma_map_failed:
 285        rx_desc = iser_conn->rx_descs;
 286        for (j = 0; j < i; j++, rx_desc++)
 287                ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
 288                                    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 289        kfree(iser_conn->rx_descs);
 290        iser_conn->rx_descs = NULL;
 291rx_desc_alloc_fail:
 292        iser_free_login_buf(iser_conn);
 293alloc_login_buf_fail:
 294        device->reg_ops->free_reg_res(ib_conn);
 295create_rdma_reg_res_failed:
 296        iser_err("failed allocating rx descriptors / data buffers\n");
 297        return -ENOMEM;
 298}
 299
 300void iser_free_rx_descriptors(struct iser_conn *iser_conn)
 301{
 302        int i;
 303        struct iser_rx_desc *rx_desc;
 304        struct ib_conn *ib_conn = &iser_conn->ib_conn;
 305        struct iser_device *device = ib_conn->device;
 306
 307        if (device->reg_ops->free_reg_res)
 308                device->reg_ops->free_reg_res(ib_conn);
 309
 310        rx_desc = iser_conn->rx_descs;
 311        for (i = 0; i < iser_conn->qp_max_recv_dtos; i++, rx_desc++)
 312                ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
 313                                    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 314        kfree(iser_conn->rx_descs);
 315        /* make sure we never redo any unmapping */
 316        iser_conn->rx_descs = NULL;
 317
 318        iser_free_login_buf(iser_conn);
 319}
 320
 321static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req)
 322{
 323        struct iser_conn *iser_conn = conn->dd_data;
 324        struct ib_conn *ib_conn = &iser_conn->ib_conn;
 325        struct iscsi_session *session = conn->session;
 326
 327        iser_dbg("req op %x flags %x\n", req->opcode, req->flags);
 328        /* check if this is the last login - going to full feature phase */
 329        if ((req->flags & ISCSI_FULL_FEATURE_PHASE) != ISCSI_FULL_FEATURE_PHASE)
 330                return 0;
 331
 332        /*
 333         * Check that there is one posted recv buffer
 334         * (for the last login response).
 335         */
 336        WARN_ON(ib_conn->post_recv_buf_count != 1);
 337
 338        if (session->discovery_sess) {
 339                iser_info("Discovery session, re-using login RX buffer\n");
 340                return 0;
 341        } else
 342                iser_info("Normal session, posting batch of RX %d buffers\n",
 343                          iser_conn->min_posted_rx);
 344
 345        /* Initial post receive buffers */
 346        if (iser_post_recvm(iser_conn, iser_conn->min_posted_rx))
 347                return -ENOMEM;
 348
 349        return 0;
 350}
 351
 352static inline bool iser_signal_comp(u8 sig_count)
 353{
 354        return ((sig_count % ISER_SIGNAL_CMD_COUNT) == 0);
 355}
 356
 357/**
 358 * iser_send_command - send command PDU
 359 */
 360int iser_send_command(struct iscsi_conn *conn,
 361                      struct iscsi_task *task)
 362{
 363        struct iser_conn *iser_conn = conn->dd_data;
 364        struct iscsi_iser_task *iser_task = task->dd_data;
 365        unsigned long edtl;
 366        int err;
 367        struct iser_data_buf *data_buf, *prot_buf;
 368        struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)task->hdr;
 369        struct scsi_cmnd *sc  =  task->sc;
 370        struct iser_tx_desc *tx_desc = &iser_task->desc;
 371        u8 sig_count = ++iser_conn->ib_conn.sig_count;
 372
 373        edtl = ntohl(hdr->data_length);
 374
 375        /* build the tx desc regd header and add it to the tx desc dto */
 376        tx_desc->type = ISCSI_TX_SCSI_COMMAND;
 377        tx_desc->cqe.done = iser_cmd_comp;
 378        iser_create_send_desc(iser_conn, tx_desc);
 379
 380        if (hdr->flags & ISCSI_FLAG_CMD_READ) {
 381                data_buf = &iser_task->data[ISER_DIR_IN];
 382                prot_buf = &iser_task->prot[ISER_DIR_IN];
 383        } else {
 384                data_buf = &iser_task->data[ISER_DIR_OUT];
 385                prot_buf = &iser_task->prot[ISER_DIR_OUT];
 386        }
 387
 388        if (scsi_sg_count(sc)) { /* using a scatter list */
 389                data_buf->sg = scsi_sglist(sc);
 390                data_buf->size = scsi_sg_count(sc);
 391        }
 392        data_buf->data_len = scsi_bufflen(sc);
 393
 394        if (scsi_prot_sg_count(sc)) {
 395                prot_buf->sg  = scsi_prot_sglist(sc);
 396                prot_buf->size = scsi_prot_sg_count(sc);
 397                prot_buf->data_len = (data_buf->data_len >>
 398                                     ilog2(sc->device->sector_size)) * 8;
 399        }
 400
 401        if (hdr->flags & ISCSI_FLAG_CMD_READ) {
 402                err = iser_prepare_read_cmd(task);
 403                if (err)
 404                        goto send_command_error;
 405        }
 406        if (hdr->flags & ISCSI_FLAG_CMD_WRITE) {
 407                err = iser_prepare_write_cmd(task,
 408                                             task->imm_count,
 409                                             task->imm_count +
 410                                             task->unsol_r2t.data_length,
 411                                             edtl);
 412                if (err)
 413                        goto send_command_error;
 414        }
 415
 416        iser_task->status = ISER_TASK_STATUS_STARTED;
 417
 418        err = iser_post_send(&iser_conn->ib_conn, tx_desc,
 419                             iser_signal_comp(sig_count));
 420        if (!err)
 421                return 0;
 422
 423send_command_error:
 424        iser_err("conn %p failed task->itt %d err %d\n",conn, task->itt, err);
 425        return err;
 426}
 427
 428/**
 429 * iser_send_data_out - send data out PDU
 430 */
 431int iser_send_data_out(struct iscsi_conn *conn,
 432                       struct iscsi_task *task,
 433                       struct iscsi_data *hdr)
 434{
 435        struct iser_conn *iser_conn = conn->dd_data;
 436        struct iscsi_iser_task *iser_task = task->dd_data;
 437        struct iser_tx_desc *tx_desc = NULL;
 438        struct iser_mem_reg *mem_reg;
 439        unsigned long buf_offset;
 440        unsigned long data_seg_len;
 441        uint32_t itt;
 442        int err;
 443        struct ib_sge *tx_dsg;
 444
 445        itt = (__force uint32_t)hdr->itt;
 446        data_seg_len = ntoh24(hdr->dlength);
 447        buf_offset   = ntohl(hdr->offset);
 448
 449        iser_dbg("%s itt %d dseg_len %d offset %d\n",
 450                 __func__,(int)itt,(int)data_seg_len,(int)buf_offset);
 451
 452        tx_desc = kmem_cache_zalloc(ig.desc_cache, GFP_ATOMIC);
 453        if (tx_desc == NULL) {
 454                iser_err("Failed to alloc desc for post dataout\n");
 455                return -ENOMEM;
 456        }
 457
 458        tx_desc->type = ISCSI_TX_DATAOUT;
 459        tx_desc->cqe.done = iser_dataout_comp;
 460        tx_desc->iser_header.flags = ISER_VER;
 461        memcpy(&tx_desc->iscsi_header, hdr, sizeof(struct iscsi_hdr));
 462
 463        /* build the tx desc */
 464        err = iser_initialize_task_headers(task, tx_desc);
 465        if (err)
 466                goto send_data_out_error;
 467
 468        mem_reg = &iser_task->rdma_reg[ISER_DIR_OUT];
 469        tx_dsg = &tx_desc->tx_sg[1];
 470        tx_dsg->addr = mem_reg->sge.addr + buf_offset;
 471        tx_dsg->length = data_seg_len;
 472        tx_dsg->lkey = mem_reg->sge.lkey;
 473        tx_desc->num_sge = 2;
 474
 475        if (buf_offset + data_seg_len > iser_task->data[ISER_DIR_OUT].data_len) {
 476                iser_err("Offset:%ld & DSL:%ld in Data-Out "
 477                         "inconsistent with total len:%ld, itt:%d\n",
 478                         buf_offset, data_seg_len,
 479                         iser_task->data[ISER_DIR_OUT].data_len, itt);
 480                err = -EINVAL;
 481                goto send_data_out_error;
 482        }
 483        iser_dbg("data-out itt: %d, offset: %ld, sz: %ld\n",
 484                 itt, buf_offset, data_seg_len);
 485
 486
 487        err = iser_post_send(&iser_conn->ib_conn, tx_desc, true);
 488        if (!err)
 489                return 0;
 490
 491send_data_out_error:
 492        kmem_cache_free(ig.desc_cache, tx_desc);
 493        iser_err("conn %p failed err %d\n", conn, err);
 494        return err;
 495}
 496
 497int iser_send_control(struct iscsi_conn *conn,
 498                      struct iscsi_task *task)
 499{
 500        struct iser_conn *iser_conn = conn->dd_data;
 501        struct iscsi_iser_task *iser_task = task->dd_data;
 502        struct iser_tx_desc *mdesc = &iser_task->desc;
 503        unsigned long data_seg_len;
 504        int err = 0;
 505        struct iser_device *device;
 506
 507        /* build the tx desc regd header and add it to the tx desc dto */
 508        mdesc->type = ISCSI_TX_CONTROL;
 509        mdesc->cqe.done = iser_ctrl_comp;
 510        iser_create_send_desc(iser_conn, mdesc);
 511
 512        device = iser_conn->ib_conn.device;
 513
 514        data_seg_len = ntoh24(task->hdr->dlength);
 515
 516        if (data_seg_len > 0) {
 517                struct iser_login_desc *desc = &iser_conn->login_desc;
 518                struct ib_sge *tx_dsg = &mdesc->tx_sg[1];
 519
 520                if (task != conn->login_task) {
 521                        iser_err("data present on non login task!!!\n");
 522                        goto send_control_error;
 523                }
 524
 525                ib_dma_sync_single_for_cpu(device->ib_device, desc->req_dma,
 526                                           task->data_count, DMA_TO_DEVICE);
 527
 528                memcpy(desc->req, task->data, task->data_count);
 529
 530                ib_dma_sync_single_for_device(device->ib_device, desc->req_dma,
 531                                              task->data_count, DMA_TO_DEVICE);
 532
 533                tx_dsg->addr = desc->req_dma;
 534                tx_dsg->length = task->data_count;
 535                tx_dsg->lkey = device->pd->local_dma_lkey;
 536                mdesc->num_sge = 2;
 537        }
 538
 539        if (task == conn->login_task) {
 540                iser_dbg("op %x dsl %lx, posting login rx buffer\n",
 541                         task->hdr->opcode, data_seg_len);
 542                err = iser_post_recvl(iser_conn);
 543                if (err)
 544                        goto send_control_error;
 545                err = iser_post_rx_bufs(conn, task->hdr);
 546                if (err)
 547                        goto send_control_error;
 548        }
 549
 550        err = iser_post_send(&iser_conn->ib_conn, mdesc, true);
 551        if (!err)
 552                return 0;
 553
 554send_control_error:
 555        iser_err("conn %p failed err %d\n",conn, err);
 556        return err;
 557}
 558
 559void iser_login_rsp(struct ib_cq *cq, struct ib_wc *wc)
 560{
 561        struct ib_conn *ib_conn = wc->qp->qp_context;
 562        struct iser_conn *iser_conn = to_iser_conn(ib_conn);
 563        struct iser_login_desc *desc = iser_login(wc->wr_cqe);
 564        struct iscsi_hdr *hdr;
 565        char *data;
 566        int length;
 567
 568        if (unlikely(wc->status != IB_WC_SUCCESS)) {
 569                iser_err_comp(wc, "login_rsp");
 570                return;
 571        }
 572
 573        ib_dma_sync_single_for_cpu(ib_conn->device->ib_device,
 574                                   desc->rsp_dma, ISER_RX_LOGIN_SIZE,
 575                                   DMA_FROM_DEVICE);
 576
 577        hdr = desc->rsp + sizeof(struct iser_ctrl);
 578        data = desc->rsp + ISER_HEADERS_LEN;
 579        length = wc->byte_len - ISER_HEADERS_LEN;
 580
 581        iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
 582                 hdr->itt, length);
 583
 584        iscsi_iser_recv(iser_conn->iscsi_conn, hdr, data, length);
 585
 586        ib_dma_sync_single_for_device(ib_conn->device->ib_device,
 587                                      desc->rsp_dma, ISER_RX_LOGIN_SIZE,
 588                                      DMA_FROM_DEVICE);
 589
 590        ib_conn->post_recv_buf_count--;
 591}
 592
 593static inline void
 594iser_inv_desc(struct iser_fr_desc *desc, u32 rkey)
 595{
 596        if (likely(rkey == desc->rsc.mr->rkey))
 597                desc->rsc.mr_valid = 0;
 598        else if (likely(rkey == desc->pi_ctx->sig_mr->rkey))
 599                desc->pi_ctx->sig_mr_valid = 0;
 600}
 601
 602static int
 603iser_check_remote_inv(struct iser_conn *iser_conn,
 604                      struct ib_wc *wc,
 605                      struct iscsi_hdr *hdr)
 606{
 607        if (wc->wc_flags & IB_WC_WITH_INVALIDATE) {
 608                struct iscsi_task *task;
 609                u32 rkey = wc->ex.invalidate_rkey;
 610
 611                iser_dbg("conn %p: remote invalidation for rkey %#x\n",
 612                         iser_conn, rkey);
 613
 614                if (unlikely(!iser_conn->snd_w_inv)) {
 615                        iser_err("conn %p: unexepected remote invalidation, "
 616                                 "terminating connection\n", iser_conn);
 617                        return -EPROTO;
 618                }
 619
 620                task = iscsi_itt_to_ctask(iser_conn->iscsi_conn, hdr->itt);
 621                if (likely(task)) {
 622                        struct iscsi_iser_task *iser_task = task->dd_data;
 623                        struct iser_fr_desc *desc;
 624
 625                        if (iser_task->dir[ISER_DIR_IN]) {
 626                                desc = iser_task->rdma_reg[ISER_DIR_IN].mem_h;
 627                                iser_inv_desc(desc, rkey);
 628                        }
 629
 630                        if (iser_task->dir[ISER_DIR_OUT]) {
 631                                desc = iser_task->rdma_reg[ISER_DIR_OUT].mem_h;
 632                                iser_inv_desc(desc, rkey);
 633                        }
 634                } else {
 635                        iser_err("failed to get task for itt=%d\n", hdr->itt);
 636                        return -EINVAL;
 637                }
 638        }
 639
 640        return 0;
 641}
 642
 643
 644void iser_task_rsp(struct ib_cq *cq, struct ib_wc *wc)
 645{
 646        struct ib_conn *ib_conn = wc->qp->qp_context;
 647        struct iser_conn *iser_conn = to_iser_conn(ib_conn);
 648        struct iser_rx_desc *desc = iser_rx(wc->wr_cqe);
 649        struct iscsi_hdr *hdr;
 650        int length;
 651        int outstanding, count, err;
 652
 653        if (unlikely(wc->status != IB_WC_SUCCESS)) {
 654                iser_err_comp(wc, "task_rsp");
 655                return;
 656        }
 657
 658        ib_dma_sync_single_for_cpu(ib_conn->device->ib_device,
 659                                   desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
 660                                   DMA_FROM_DEVICE);
 661
 662        hdr = &desc->iscsi_header;
 663        length = wc->byte_len - ISER_HEADERS_LEN;
 664
 665        iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
 666                 hdr->itt, length);
 667
 668        if (iser_check_remote_inv(iser_conn, wc, hdr)) {
 669                iscsi_conn_failure(iser_conn->iscsi_conn,
 670                                   ISCSI_ERR_CONN_FAILED);
 671                return;
 672        }
 673
 674        iscsi_iser_recv(iser_conn->iscsi_conn, hdr, desc->data, length);
 675
 676        ib_dma_sync_single_for_device(ib_conn->device->ib_device,
 677                                      desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
 678                                      DMA_FROM_DEVICE);
 679
 680        /* decrementing conn->post_recv_buf_count only --after-- freeing the   *
 681         * task eliminates the need to worry on tasks which are completed in   *
 682         * parallel to the execution of iser_conn_term. So the code that waits *
 683         * for the posted rx bufs refcount to become zero handles everything   */
 684        ib_conn->post_recv_buf_count--;
 685
 686        outstanding = ib_conn->post_recv_buf_count;
 687        if (outstanding + iser_conn->min_posted_rx <= iser_conn->qp_max_recv_dtos) {
 688                count = min(iser_conn->qp_max_recv_dtos - outstanding,
 689                            iser_conn->min_posted_rx);
 690                err = iser_post_recvm(iser_conn, count);
 691                if (err)
 692                        iser_err("posting %d rx bufs err %d\n", count, err);
 693        }
 694}
 695
 696void iser_cmd_comp(struct ib_cq *cq, struct ib_wc *wc)
 697{
 698        if (unlikely(wc->status != IB_WC_SUCCESS))
 699                iser_err_comp(wc, "command");
 700}
 701
 702void iser_ctrl_comp(struct ib_cq *cq, struct ib_wc *wc)
 703{
 704        struct iser_tx_desc *desc = iser_tx(wc->wr_cqe);
 705        struct iscsi_task *task;
 706
 707        if (unlikely(wc->status != IB_WC_SUCCESS)) {
 708                iser_err_comp(wc, "control");
 709                return;
 710        }
 711
 712        /* this arithmetic is legal by libiscsi dd_data allocation */
 713        task = (void *)desc - sizeof(struct iscsi_task);
 714        if (task->hdr->itt == RESERVED_ITT)
 715                iscsi_put_task(task);
 716}
 717
 718void iser_dataout_comp(struct ib_cq *cq, struct ib_wc *wc)
 719{
 720        struct iser_tx_desc *desc = iser_tx(wc->wr_cqe);
 721        struct ib_conn *ib_conn = wc->qp->qp_context;
 722        struct iser_device *device = ib_conn->device;
 723
 724        if (unlikely(wc->status != IB_WC_SUCCESS))
 725                iser_err_comp(wc, "dataout");
 726
 727        ib_dma_unmap_single(device->ib_device, desc->dma_addr,
 728                            ISER_HEADERS_LEN, DMA_TO_DEVICE);
 729        kmem_cache_free(ig.desc_cache, desc);
 730}
 731
 732void iser_task_rdma_init(struct iscsi_iser_task *iser_task)
 733
 734{
 735        iser_task->status = ISER_TASK_STATUS_INIT;
 736
 737        iser_task->dir[ISER_DIR_IN] = 0;
 738        iser_task->dir[ISER_DIR_OUT] = 0;
 739
 740        iser_task->data[ISER_DIR_IN].data_len  = 0;
 741        iser_task->data[ISER_DIR_OUT].data_len = 0;
 742
 743        iser_task->prot[ISER_DIR_IN].data_len  = 0;
 744        iser_task->prot[ISER_DIR_OUT].data_len = 0;
 745
 746        memset(&iser_task->rdma_reg[ISER_DIR_IN], 0,
 747               sizeof(struct iser_mem_reg));
 748        memset(&iser_task->rdma_reg[ISER_DIR_OUT], 0,
 749               sizeof(struct iser_mem_reg));
 750}
 751
 752void iser_task_rdma_finalize(struct iscsi_iser_task *iser_task)
 753{
 754        int prot_count = scsi_prot_sg_count(iser_task->sc);
 755
 756        if (iser_task->dir[ISER_DIR_IN]) {
 757                iser_unreg_rdma_mem(iser_task, ISER_DIR_IN);
 758                iser_dma_unmap_task_data(iser_task,
 759                                         &iser_task->data[ISER_DIR_IN],
 760                                         DMA_FROM_DEVICE);
 761                if (prot_count)
 762                        iser_dma_unmap_task_data(iser_task,
 763                                                 &iser_task->prot[ISER_DIR_IN],
 764                                                 DMA_FROM_DEVICE);
 765        }
 766
 767        if (iser_task->dir[ISER_DIR_OUT]) {
 768                iser_unreg_rdma_mem(iser_task, ISER_DIR_OUT);
 769                iser_dma_unmap_task_data(iser_task,
 770                                         &iser_task->data[ISER_DIR_OUT],
 771                                         DMA_TO_DEVICE);
 772                if (prot_count)
 773                        iser_dma_unmap_task_data(iser_task,
 774                                                 &iser_task->prot[ISER_DIR_OUT],
 775                                                 DMA_TO_DEVICE);
 776        }
 777}
 778