drivers/infiniband/ulp/iser/iser_initiator.c

   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  */
  48 static 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  */
  98 static int
  99 iser_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 */
 162 static 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
 175 static 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
 197 static 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
 226 free_rsp:
 227         kfree(desc->rsp);
 228 unmap_req:
 229         ib_dma_unmap_single(device->ib_device, desc->req_dma,
 230                             ISCSI_DEF_MAX_RECV_SEG_LEN,
 231                             DMA_TO_DEVICE);
 232 free_req:
 233         kfree(desc->req);
 234
 235         return -ENOMEM;
 236 }
 237
 238 int 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
 284 rx_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;
 291 rx_desc_alloc_fail:
 292         iser_free_login_buf(iser_conn);
 293 alloc_login_buf_fail:
 294         device->reg_ops->free_reg_res(ib_conn);
 295 create_rdma_reg_res_failed:
 296         iser_err("failed allocating rx descriptors / data buffers\n");
 297         return -ENOMEM;
 298 }
 299
 300 void 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
 321 static 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
 352 static 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  */
 360 int 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
 423 send_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  */
 431 int 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
 491 send_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
 497 int 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
 554 send_control_error:
 555         iser_err("conn %p failed err %d\n",conn, err);
 556         return err;
 557 }
 558
 559 void 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
 593 static inline void
 594 iser_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
 602 static int
 603 iser_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: unexpected 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
 644 void 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
 696 void 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
 702 void 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
 718 void 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
 732 void 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
 752 void 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 }