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                 if (buf_out->data_len > imm_sz) {
 141                         hdr->write_stag = cpu_to_be32(mem_reg->rkey);
 142                         hdr->write_va = cpu_to_be64(mem_reg->sge.addr + unsol_sz);
 143                 }
 144
 145                 iser_dbg("Cmd itt:%d, WRITE tags, RKEY:%#.4X "
 146                          "VA:%#llX + unsol:%d\n",
 147                          task->itt, mem_reg->rkey,
 148                          (unsigned long long)mem_reg->sge.addr, unsol_sz);
 149         }
 150
 151         if (imm_sz > 0) {
 152                 iser_dbg("Cmd itt:%d, WRITE, adding imm.data sz: %d\n",
 153                          task->itt, imm_sz);
 154                 tx_dsg->addr = mem_reg->sge.addr;
 155                 tx_dsg->length = imm_sz;
 156                 tx_dsg->lkey = mem_reg->sge.lkey;
 157                 iser_task->desc.num_sge = 2;
 158         }
 159
 160         return 0;
 161 }
 162
 163 /* creates a new tx descriptor and adds header regd buffer */
 164 static void iser_create_send_desc(struct iser_conn      *iser_conn,
 165                                   struct iser_tx_desc   *tx_desc)
 166 {
 167         struct iser_device *device = iser_conn->ib_conn.device;
 168
 169         ib_dma_sync_single_for_cpu(device->ib_device,
 170                 tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
 171
 172         memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
 173         tx_desc->iser_header.flags = ISER_VER;
 174         tx_desc->num_sge = 1;
 175 }
 176
 177 static void iser_free_login_buf(struct iser_conn *iser_conn)
 178 {
 179         struct iser_device *device = iser_conn->ib_conn.device;
 180         struct iser_login_desc *desc = &iser_conn->login_desc;
 181
 182         if (!desc->req)
 183                 return;
 184
 185         ib_dma_unmap_single(device->ib_device, desc->req_dma,
 186                             ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);
 187
 188         ib_dma_unmap_single(device->ib_device, desc->rsp_dma,
 189                             ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);
 190
 191         kfree(desc->req);
 192         kfree(desc->rsp);
 193
 194         /* make sure we never redo any unmapping */
 195         desc->req = NULL;
 196         desc->rsp = NULL;
 197 }
 198
 199 static int iser_alloc_login_buf(struct iser_conn *iser_conn)
 200 {
 201         struct iser_device *device = iser_conn->ib_conn.device;
 202         struct iser_login_desc *desc = &iser_conn->login_desc;
 203
 204         desc->req = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
 205         if (!desc->req)
 206                 return -ENOMEM;
 207
 208         desc->req_dma = ib_dma_map_single(device->ib_device, desc->req,
 209                                           ISCSI_DEF_MAX_RECV_SEG_LEN,
 210                                           DMA_TO_DEVICE);
 211         if (ib_dma_mapping_error(device->ib_device,
 212                                 desc->req_dma))
 213                 goto free_req;
 214
 215         desc->rsp = kmalloc(ISER_RX_LOGIN_SIZE, GFP_KERNEL);
 216         if (!desc->rsp)
 217                 goto unmap_req;
 218
 219         desc->rsp_dma = ib_dma_map_single(device->ib_device, desc->rsp,
 220                                            ISER_RX_LOGIN_SIZE,
 221                                            DMA_FROM_DEVICE);
 222         if (ib_dma_mapping_error(device->ib_device,
 223                                 desc->rsp_dma))
 224                 goto free_rsp;
 225
 226         return 0;
 227
 228 free_rsp:
 229         kfree(desc->rsp);
 230 unmap_req:
 231         ib_dma_unmap_single(device->ib_device, desc->req_dma,
 232                             ISCSI_DEF_MAX_RECV_SEG_LEN,
 233                             DMA_TO_DEVICE);
 234 free_req:
 235         kfree(desc->req);
 236
 237         return -ENOMEM;
 238 }
 239
 240 int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
 241                               struct iscsi_session *session)
 242 {
 243         int i, j;
 244         u64 dma_addr;
 245         struct iser_rx_desc *rx_desc;
 246         struct ib_sge       *rx_sg;
 247         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 248         struct iser_device *device = ib_conn->device;
 249
 250         iser_conn->qp_max_recv_dtos = session->cmds_max;
 251         iser_conn->qp_max_recv_dtos_mask = session->cmds_max - 1; /* cmds_max is 2^N */
 252         iser_conn->min_posted_rx = iser_conn->qp_max_recv_dtos >> 2;
 253
 254         if (device->reg_ops->alloc_reg_res(ib_conn, session->scsi_cmds_max,
 255                                            iser_conn->scsi_sg_tablesize))
 256                 goto create_rdma_reg_res_failed;
 257
 258         if (iser_alloc_login_buf(iser_conn))
 259                 goto alloc_login_buf_fail;
 260
 261         iser_conn->num_rx_descs = session->cmds_max;
 262         iser_conn->rx_descs = kmalloc(iser_conn->num_rx_descs *
 263                                 sizeof(struct iser_rx_desc), GFP_KERNEL);
 264         if (!iser_conn->rx_descs)
 265                 goto rx_desc_alloc_fail;
 266
 267         rx_desc = iser_conn->rx_descs;
 268
 269         for (i = 0; i < iser_conn->qp_max_recv_dtos; i++, rx_desc++)  {
 270                 dma_addr = ib_dma_map_single(device->ib_device, (void *)rx_desc,
 271                                         ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 272                 if (ib_dma_mapping_error(device->ib_device, dma_addr))
 273                         goto rx_desc_dma_map_failed;
 274
 275                 rx_desc->dma_addr = dma_addr;
 276                 rx_desc->cqe.done = iser_task_rsp;
 277                 rx_sg = &rx_desc->rx_sg;
 278                 rx_sg->addr = rx_desc->dma_addr;
 279                 rx_sg->length = ISER_RX_PAYLOAD_SIZE;
 280                 rx_sg->lkey = device->pd->local_dma_lkey;
 281         }
 282
 283         iser_conn->rx_desc_head = 0;
 284         return 0;
 285
 286 rx_desc_dma_map_failed:
 287         rx_desc = iser_conn->rx_descs;
 288         for (j = 0; j < i; j++, rx_desc++)
 289                 ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
 290                                     ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 291         kfree(iser_conn->rx_descs);
 292         iser_conn->rx_descs = NULL;
 293 rx_desc_alloc_fail:
 294         iser_free_login_buf(iser_conn);
 295 alloc_login_buf_fail:
 296         device->reg_ops->free_reg_res(ib_conn);
 297 create_rdma_reg_res_failed:
 298         iser_err("failed allocating rx descriptors / data buffers\n");
 299         return -ENOMEM;
 300 }
 301
 302 void iser_free_rx_descriptors(struct iser_conn *iser_conn)
 303 {
 304         int i;
 305         struct iser_rx_desc *rx_desc;
 306         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 307         struct iser_device *device = ib_conn->device;
 308
 309         if (device->reg_ops->free_reg_res)
 310                 device->reg_ops->free_reg_res(ib_conn);
 311
 312         rx_desc = iser_conn->rx_descs;
 313         for (i = 0; i < iser_conn->qp_max_recv_dtos; i++, rx_desc++)
 314                 ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
 315                                     ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 316         kfree(iser_conn->rx_descs);
 317         /* make sure we never redo any unmapping */
 318         iser_conn->rx_descs = NULL;
 319
 320         iser_free_login_buf(iser_conn);
 321 }
 322
 323 static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req)
 324 {
 325         struct iser_conn *iser_conn = conn->dd_data;
 326         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 327         struct iscsi_session *session = conn->session;
 328
 329         iser_dbg("req op %x flags %x\n", req->opcode, req->flags);
 330         /* check if this is the last login - going to full feature phase */
 331         if ((req->flags & ISCSI_FULL_FEATURE_PHASE) != ISCSI_FULL_FEATURE_PHASE)
 332                 return 0;
 333
 334         /*
 335          * Check that there is one posted recv buffer
 336          * (for the last login response).
 337          */
 338         WARN_ON(ib_conn->post_recv_buf_count != 1);
 339
 340         if (session->discovery_sess) {
 341                 iser_info("Discovery session, re-using login RX buffer\n");
 342                 return 0;
 343         } else
 344                 iser_info("Normal session, posting batch of RX %d buffers\n",
 345                           iser_conn->min_posted_rx);
 346
 347         /* Initial post receive buffers */
 348         if (iser_post_recvm(iser_conn, iser_conn->min_posted_rx))
 349                 return -ENOMEM;
 350
 351         return 0;
 352 }
 353
 354 static inline bool iser_signal_comp(u8 sig_count)
 355 {
 356         return ((sig_count % ISER_SIGNAL_CMD_COUNT) == 0);
 357 }
 358
 359 /**
 360  * iser_send_command - send command PDU
 361  */
 362 int iser_send_command(struct iscsi_conn *conn,
 363                       struct iscsi_task *task)
 364 {
 365         struct iser_conn *iser_conn = conn->dd_data;
 366         struct iscsi_iser_task *iser_task = task->dd_data;
 367         unsigned long edtl;
 368         int err;
 369         struct iser_data_buf *data_buf, *prot_buf;
 370         struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)task->hdr;
 371         struct scsi_cmnd *sc  =  task->sc;
 372         struct iser_tx_desc *tx_desc = &iser_task->desc;
 373         u8 sig_count = ++iser_conn->ib_conn.sig_count;
 374
 375         edtl = ntohl(hdr->data_length);
 376
 377         /* build the tx desc regd header and add it to the tx desc dto */
 378         tx_desc->type = ISCSI_TX_SCSI_COMMAND;
 379         tx_desc->cqe.done = iser_cmd_comp;
 380         iser_create_send_desc(iser_conn, tx_desc);
 381
 382         if (hdr->flags & ISCSI_FLAG_CMD_READ) {
 383                 data_buf = &iser_task->data[ISER_DIR_IN];
 384                 prot_buf = &iser_task->prot[ISER_DIR_IN];
 385         } else {
 386                 data_buf = &iser_task->data[ISER_DIR_OUT];
 387                 prot_buf = &iser_task->prot[ISER_DIR_OUT];
 388         }
 389
 390         if (scsi_sg_count(sc)) { /* using a scatter list */
 391                 data_buf->sg = scsi_sglist(sc);
 392                 data_buf->size = scsi_sg_count(sc);
 393         }
 394         data_buf->data_len = scsi_bufflen(sc);
 395
 396         if (scsi_prot_sg_count(sc)) {
 397                 prot_buf->sg  = scsi_prot_sglist(sc);
 398                 prot_buf->size = scsi_prot_sg_count(sc);
 399                 prot_buf->data_len = (data_buf->data_len >>
 400                                      ilog2(sc->device->sector_size)) * 8;
 401         }
 402
 403         if (hdr->flags & ISCSI_FLAG_CMD_READ) {
 404                 err = iser_prepare_read_cmd(task);
 405                 if (err)
 406                         goto send_command_error;
 407         }
 408         if (hdr->flags & ISCSI_FLAG_CMD_WRITE) {
 409                 err = iser_prepare_write_cmd(task,
 410                                              task->imm_count,
 411                                              task->imm_count +
 412                                              task->unsol_r2t.data_length,
 413                                              edtl);
 414                 if (err)
 415                         goto send_command_error;
 416         }
 417
 418         iser_task->status = ISER_TASK_STATUS_STARTED;
 419
 420         err = iser_post_send(&iser_conn->ib_conn, tx_desc,
 421                              iser_signal_comp(sig_count));
 422         if (!err)
 423                 return 0;
 424
 425 send_command_error:
 426         iser_err("conn %p failed task->itt %d err %d\n",conn, task->itt, err);
 427         return err;
 428 }
 429
 430 /**
 431  * iser_send_data_out - send data out PDU
 432  */
 433 int iser_send_data_out(struct iscsi_conn *conn,
 434                        struct iscsi_task *task,
 435                        struct iscsi_data *hdr)
 436 {
 437         struct iser_conn *iser_conn = conn->dd_data;
 438         struct iscsi_iser_task *iser_task = task->dd_data;
 439         struct iser_tx_desc *tx_desc = NULL;
 440         struct iser_mem_reg *mem_reg;
 441         unsigned long buf_offset;
 442         unsigned long data_seg_len;
 443         uint32_t itt;
 444         int err;
 445         struct ib_sge *tx_dsg;
 446
 447         itt = (__force uint32_t)hdr->itt;
 448         data_seg_len = ntoh24(hdr->dlength);
 449         buf_offset   = ntohl(hdr->offset);
 450
 451         iser_dbg("%s itt %d dseg_len %d offset %d\n",
 452                  __func__,(int)itt,(int)data_seg_len,(int)buf_offset);
 453
 454         tx_desc = kmem_cache_zalloc(ig.desc_cache, GFP_ATOMIC);
 455         if (tx_desc == NULL) {
 456                 iser_err("Failed to alloc desc for post dataout\n");
 457                 return -ENOMEM;
 458         }
 459
 460         tx_desc->type = ISCSI_TX_DATAOUT;
 461         tx_desc->cqe.done = iser_dataout_comp;
 462         tx_desc->iser_header.flags = ISER_VER;
 463         memcpy(&tx_desc->iscsi_header, hdr, sizeof(struct iscsi_hdr));
 464
 465         /* build the tx desc */
 466         err = iser_initialize_task_headers(task, tx_desc);
 467         if (err)
 468                 goto send_data_out_error;
 469
 470         mem_reg = &iser_task->rdma_reg[ISER_DIR_OUT];
 471         tx_dsg = &tx_desc->tx_sg[1];
 472         tx_dsg->addr = mem_reg->sge.addr + buf_offset;
 473         tx_dsg->length = data_seg_len;
 474         tx_dsg->lkey = mem_reg->sge.lkey;
 475         tx_desc->num_sge = 2;
 476
 477         if (buf_offset + data_seg_len > iser_task->data[ISER_DIR_OUT].data_len) {
 478                 iser_err("Offset:%ld & DSL:%ld in Data-Out "
 479                          "inconsistent with total len:%ld, itt:%d\n",
 480                          buf_offset, data_seg_len,
 481                          iser_task->data[ISER_DIR_OUT].data_len, itt);
 482                 err = -EINVAL;
 483                 goto send_data_out_error;
 484         }
 485         iser_dbg("data-out itt: %d, offset: %ld, sz: %ld\n",
 486                  itt, buf_offset, data_seg_len);
 487
 488
 489         err = iser_post_send(&iser_conn->ib_conn, tx_desc, true);
 490         if (!err)
 491                 return 0;
 492
 493 send_data_out_error:
 494         kmem_cache_free(ig.desc_cache, tx_desc);
 495         iser_err("conn %p failed err %d\n", conn, err);
 496         return err;
 497 }
 498
 499 int iser_send_control(struct iscsi_conn *conn,
 500                       struct iscsi_task *task)
 501 {
 502         struct iser_conn *iser_conn = conn->dd_data;
 503         struct iscsi_iser_task *iser_task = task->dd_data;
 504         struct iser_tx_desc *mdesc = &iser_task->desc;
 505         unsigned long data_seg_len;
 506         int err = 0;
 507         struct iser_device *device;
 508
 509         /* build the tx desc regd header and add it to the tx desc dto */
 510         mdesc->type = ISCSI_TX_CONTROL;
 511         mdesc->cqe.done = iser_ctrl_comp;
 512         iser_create_send_desc(iser_conn, mdesc);
 513
 514         device = iser_conn->ib_conn.device;
 515
 516         data_seg_len = ntoh24(task->hdr->dlength);
 517
 518         if (data_seg_len > 0) {
 519                 struct iser_login_desc *desc = &iser_conn->login_desc;
 520                 struct ib_sge *tx_dsg = &mdesc->tx_sg[1];
 521
 522                 if (task != conn->login_task) {
 523                         iser_err("data present on non login task!!!\n");
 524                         goto send_control_error;
 525                 }
 526
 527                 ib_dma_sync_single_for_cpu(device->ib_device, desc->req_dma,
 528                                            task->data_count, DMA_TO_DEVICE);
 529
 530                 memcpy(desc->req, task->data, task->data_count);
 531
 532                 ib_dma_sync_single_for_device(device->ib_device, desc->req_dma,
 533                                               task->data_count, DMA_TO_DEVICE);
 534
 535                 tx_dsg->addr = desc->req_dma;
 536                 tx_dsg->length = task->data_count;
 537                 tx_dsg->lkey = device->pd->local_dma_lkey;
 538                 mdesc->num_sge = 2;
 539         }
 540
 541         if (task == conn->login_task) {
 542                 iser_dbg("op %x dsl %lx, posting login rx buffer\n",
 543                          task->hdr->opcode, data_seg_len);
 544                 err = iser_post_recvl(iser_conn);
 545                 if (err)
 546                         goto send_control_error;
 547                 err = iser_post_rx_bufs(conn, task->hdr);
 548                 if (err)
 549                         goto send_control_error;
 550         }
 551
 552         err = iser_post_send(&iser_conn->ib_conn, mdesc, true);
 553         if (!err)
 554                 return 0;
 555
 556 send_control_error:
 557         iser_err("conn %p failed err %d\n",conn, err);
 558         return err;
 559 }
 560
 561 void iser_login_rsp(struct ib_cq *cq, struct ib_wc *wc)
 562 {
 563         struct ib_conn *ib_conn = wc->qp->qp_context;
 564         struct iser_conn *iser_conn = to_iser_conn(ib_conn);
 565         struct iser_login_desc *desc = iser_login(wc->wr_cqe);
 566         struct iscsi_hdr *hdr;
 567         char *data;
 568         int length;
 569
 570         if (unlikely(wc->status != IB_WC_SUCCESS)) {
 571                 iser_err_comp(wc, "login_rsp");
 572                 return;
 573         }
 574
 575         ib_dma_sync_single_for_cpu(ib_conn->device->ib_device,
 576                                    desc->rsp_dma, ISER_RX_LOGIN_SIZE,
 577                                    DMA_FROM_DEVICE);
 578
 579         hdr = desc->rsp + sizeof(struct iser_ctrl);
 580         data = desc->rsp + ISER_HEADERS_LEN;
 581         length = wc->byte_len - ISER_HEADERS_LEN;
 582
 583         iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
 584                  hdr->itt, length);
 585
 586         iscsi_iser_recv(iser_conn->iscsi_conn, hdr, data, length);
 587
 588         ib_dma_sync_single_for_device(ib_conn->device->ib_device,
 589                                       desc->rsp_dma, ISER_RX_LOGIN_SIZE,
 590                                       DMA_FROM_DEVICE);
 591
 592         ib_conn->post_recv_buf_count--;
 593 }
 594
 595 static inline void
 596 iser_inv_desc(struct iser_fr_desc *desc, u32 rkey)
 597 {
 598         if (likely(rkey == desc->rsc.mr->rkey))
 599                 desc->rsc.mr_valid = 0;
 600         else if (likely(rkey == desc->pi_ctx->sig_mr->rkey))
 601                 desc->pi_ctx->sig_mr_valid = 0;
 602 }
 603
 604 static int
 605 iser_check_remote_inv(struct iser_conn *iser_conn,
 606                       struct ib_wc *wc,
 607                       struct iscsi_hdr *hdr)
 608 {
 609         if (wc->wc_flags & IB_WC_WITH_INVALIDATE) {
 610                 struct iscsi_task *task;
 611                 u32 rkey = wc->ex.invalidate_rkey;
 612
 613                 iser_dbg("conn %p: remote invalidation for rkey %#x\n",
 614                          iser_conn, rkey);
 615
 616                 if (unlikely(!iser_conn->snd_w_inv)) {
 617                         iser_err("conn %p: unexpected remote invalidation, "
 618                                  "terminating connection\n", iser_conn);
 619                         return -EPROTO;
 620                 }
 621
 622                 task = iscsi_itt_to_ctask(iser_conn->iscsi_conn, hdr->itt);
 623                 if (likely(task)) {
 624                         struct iscsi_iser_task *iser_task = task->dd_data;
 625                         struct iser_fr_desc *desc;
 626
 627                         if (iser_task->dir[ISER_DIR_IN]) {
 628                                 desc = iser_task->rdma_reg[ISER_DIR_IN].mem_h;
 629                                 iser_inv_desc(desc, rkey);
 630                         }
 631
 632                         if (iser_task->dir[ISER_DIR_OUT]) {
 633                                 desc = iser_task->rdma_reg[ISER_DIR_OUT].mem_h;
 634                                 iser_inv_desc(desc, rkey);
 635                         }
 636                 } else {
 637                         iser_err("failed to get task for itt=%d\n", hdr->itt);
 638                         return -EINVAL;
 639                 }
 640         }
 641
 642         return 0;
 643 }
 644
 645
 646 void iser_task_rsp(struct ib_cq *cq, struct ib_wc *wc)
 647 {
 648         struct ib_conn *ib_conn = wc->qp->qp_context;
 649         struct iser_conn *iser_conn = to_iser_conn(ib_conn);
 650         struct iser_rx_desc *desc = iser_rx(wc->wr_cqe);
 651         struct iscsi_hdr *hdr;
 652         int length;
 653         int outstanding, count, err;
 654
 655         if (unlikely(wc->status != IB_WC_SUCCESS)) {
 656                 iser_err_comp(wc, "task_rsp");
 657                 return;
 658         }
 659
 660         ib_dma_sync_single_for_cpu(ib_conn->device->ib_device,
 661                                    desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
 662                                    DMA_FROM_DEVICE);
 663
 664         hdr = &desc->iscsi_header;
 665         length = wc->byte_len - ISER_HEADERS_LEN;
 666
 667         iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
 668                  hdr->itt, length);
 669
 670         if (iser_check_remote_inv(iser_conn, wc, hdr)) {
 671                 iscsi_conn_failure(iser_conn->iscsi_conn,
 672                                    ISCSI_ERR_CONN_FAILED);
 673                 return;
 674         }
 675
 676         iscsi_iser_recv(iser_conn->iscsi_conn, hdr, desc->data, length);
 677
 678         ib_dma_sync_single_for_device(ib_conn->device->ib_device,
 679                                       desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
 680                                       DMA_FROM_DEVICE);
 681
 682         /* decrementing conn->post_recv_buf_count only --after-- freeing the   *
 683          * task eliminates the need to worry on tasks which are completed in   *
 684          * parallel to the execution of iser_conn_term. So the code that waits *
 685          * for the posted rx bufs refcount to become zero handles everything   */
 686         ib_conn->post_recv_buf_count--;
 687
 688         outstanding = ib_conn->post_recv_buf_count;
 689         if (outstanding + iser_conn->min_posted_rx <= iser_conn->qp_max_recv_dtos) {
 690                 count = min(iser_conn->qp_max_recv_dtos - outstanding,
 691                             iser_conn->min_posted_rx);
 692                 err = iser_post_recvm(iser_conn, count);
 693                 if (err)
 694                         iser_err("posting %d rx bufs err %d\n", count, err);
 695         }
 696 }
 697
 698 void iser_cmd_comp(struct ib_cq *cq, struct ib_wc *wc)
 699 {
 700         if (unlikely(wc->status != IB_WC_SUCCESS))
 701                 iser_err_comp(wc, "command");
 702 }
 703
 704 void iser_ctrl_comp(struct ib_cq *cq, struct ib_wc *wc)
 705 {
 706         struct iser_tx_desc *desc = iser_tx(wc->wr_cqe);
 707         struct iscsi_task *task;
 708
 709         if (unlikely(wc->status != IB_WC_SUCCESS)) {
 710                 iser_err_comp(wc, "control");
 711                 return;
 712         }
 713
 714         /* this arithmetic is legal by libiscsi dd_data allocation */
 715         task = (void *)desc - sizeof(struct iscsi_task);
 716         if (task->hdr->itt == RESERVED_ITT)
 717                 iscsi_put_task(task);
 718 }
 719
 720 void iser_dataout_comp(struct ib_cq *cq, struct ib_wc *wc)
 721 {
 722         struct iser_tx_desc *desc = iser_tx(wc->wr_cqe);
 723         struct ib_conn *ib_conn = wc->qp->qp_context;
 724         struct iser_device *device = ib_conn->device;
 725
 726         if (unlikely(wc->status != IB_WC_SUCCESS))
 727                 iser_err_comp(wc, "dataout");
 728
 729         ib_dma_unmap_single(device->ib_device, desc->dma_addr,
 730                             ISER_HEADERS_LEN, DMA_TO_DEVICE);
 731         kmem_cache_free(ig.desc_cache, desc);
 732 }
 733
 734 void iser_task_rdma_init(struct iscsi_iser_task *iser_task)
 735
 736 {
 737         iser_task->status = ISER_TASK_STATUS_INIT;
 738
 739         iser_task->dir[ISER_DIR_IN] = 0;
 740         iser_task->dir[ISER_DIR_OUT] = 0;
 741
 742         iser_task->data[ISER_DIR_IN].data_len  = 0;
 743         iser_task->data[ISER_DIR_OUT].data_len = 0;
 744
 745         iser_task->prot[ISER_DIR_IN].data_len  = 0;
 746         iser_task->prot[ISER_DIR_OUT].data_len = 0;
 747
 748         memset(&iser_task->rdma_reg[ISER_DIR_IN], 0,
 749                sizeof(struct iser_mem_reg));
 750         memset(&iser_task->rdma_reg[ISER_DIR_OUT], 0,
 751                sizeof(struct iser_mem_reg));
 752 }
 753
 754 void iser_task_rdma_finalize(struct iscsi_iser_task *iser_task)
 755 {
 756         int prot_count = scsi_prot_sg_count(iser_task->sc);
 757
 758         if (iser_task->dir[ISER_DIR_IN]) {
 759                 iser_unreg_rdma_mem(iser_task, ISER_DIR_IN);
 760                 iser_dma_unmap_task_data(iser_task,
 761                                          &iser_task->data[ISER_DIR_IN],
 762                                          DMA_FROM_DEVICE);
 763                 if (prot_count)
 764                         iser_dma_unmap_task_data(iser_task,
 765                                                  &iser_task->prot[ISER_DIR_IN],
 766                                                  DMA_FROM_DEVICE);
 767         }
 768
 769         if (iser_task->dir[ISER_DIR_OUT]) {
 770                 iser_unreg_rdma_mem(iser_task, ISER_DIR_OUT);
 771                 iser_dma_unmap_task_data(iser_task,
 772                                          &iser_task->data[ISER_DIR_OUT],
 773                                          DMA_TO_DEVICE);
 774                 if (prot_count)
 775                         iser_dma_unmap_task_data(iser_task,
 776                                                  &iser_task->prot[ISER_DIR_OUT],
 777                                                  DMA_TO_DEVICE);
 778         }
 779 }