kernel/drivers/scsi/snic/snic_disc.c

   1 /*
   2  * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
   3  *
   4  * This program is free software; you may redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   9  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  10  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  11  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  12  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  13  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  14  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  15  * SOFTWARE.
  16  */
  17
  18 #include <linux/errno.h>
  19 #include <linux/mempool.h>
  20
  21 #include <scsi/scsi_tcq.h>
  22
  23 #include "snic_disc.h"
  24 #include "snic.h"
  25 #include "snic_io.h"
  26
  27
  28 /* snic target types */
  29 static const char * const snic_tgt_type_str[] = {
  30         [SNIC_TGT_DAS] = "DAS",
  31         [SNIC_TGT_SAN] = "SAN",
  32 };
  33
  34 static inline const char *
  35 snic_tgt_type_to_str(int typ)
  36 {
  37         return ((typ > SNIC_TGT_NONE && typ <= SNIC_TGT_SAN) ?
  38                  snic_tgt_type_str[typ] : "Unknown");
  39 }
  40
  41 static const char * const snic_tgt_state_str[] = {
  42         [SNIC_TGT_STAT_INIT]    = "INIT",
  43         [SNIC_TGT_STAT_ONLINE]  = "ONLINE",
  44         [SNIC_TGT_STAT_OFFLINE] = "OFFLINE",
  45         [SNIC_TGT_STAT_DEL]     = "DELETION IN PROGRESS",
  46 };
  47
  48 const char *
  49 snic_tgt_state_to_str(int state)
  50 {
  51         return ((state >= SNIC_TGT_STAT_INIT && state <= SNIC_TGT_STAT_DEL) ?
  52                 snic_tgt_state_str[state] : "UNKNOWN");
  53 }
  54
  55 /*
  56  * Initiate report_tgt req desc
  57  */
  58 static void
  59 snic_report_tgt_init(struct snic_host_req *req, u32 hid, u8 *buf, u32 len,
  60                      dma_addr_t rsp_buf_pa, ulong ctx)
  61 {
  62         struct snic_sg_desc *sgd = NULL;
  63
  64
  65         snic_io_hdr_enc(&req->hdr, SNIC_REQ_REPORT_TGTS, 0, SCSI_NO_TAG, hid,
  66                         1, ctx);
  67
  68         req->u.rpt_tgts.sg_cnt = cpu_to_le16(1);
  69         sgd = req_to_sgl(req);
  70         sgd[0].addr = cpu_to_le64(rsp_buf_pa);
  71         sgd[0].len = cpu_to_le32(len);
  72         sgd[0]._resvd = 0;
  73         req->u.rpt_tgts.sg_addr = cpu_to_le64((ulong)sgd);
  74 }
  75
  76 /*
  77  * snic_queue_report_tgt_req: Queues report target request.
  78  */
  79 static int
  80 snic_queue_report_tgt_req(struct snic *snic)
  81 {
  82         struct snic_req_info *rqi = NULL;
  83         u32 ntgts, buf_len = 0;
  84         u8 *buf = NULL;
  85         dma_addr_t pa = 0;
  86         int ret = 0;
  87
  88         rqi = snic_req_init(snic, 1);
  89         if (!rqi) {
  90                 ret = -ENOMEM;
  91                 goto error;
  92         }
  93
  94         if (snic->fwinfo.max_tgts)
  95                 ntgts = min_t(u32, snic->fwinfo.max_tgts, snic->shost->max_id);
  96         else
  97                 ntgts = snic->shost->max_id;
  98
  99         /* Allocate Response Buffer */
 100         SNIC_BUG_ON(ntgts == 0);
 101         buf_len = ntgts * sizeof(struct snic_tgt_id) + SNIC_SG_DESC_ALIGN;
 102
 103         buf = kzalloc(buf_len, GFP_KERNEL|GFP_DMA);
 104         if (!buf) {
 105                 snic_req_free(snic, rqi);
 106                 SNIC_HOST_ERR(snic->shost, "Resp Buf Alloc Failed.\n");
 107
 108                 ret = -ENOMEM;
 109                 goto error;
 110         }
 111
 112         SNIC_BUG_ON((((unsigned long)buf) % SNIC_SG_DESC_ALIGN) != 0);
 113
 114         pa = pci_map_single(snic->pdev, buf, buf_len, PCI_DMA_FROMDEVICE);
 115         if (pci_dma_mapping_error(snic->pdev, pa)) {
 116                 kfree(buf);
 117                 snic_req_free(snic, rqi);
 118                 SNIC_HOST_ERR(snic->shost,
 119                               "Rpt-tgt rspbuf %p: PCI DMA Mapping Failed\n",
 120                               buf);
 121                 ret = -EINVAL;
 122
 123                 goto error;
 124         }
 125
 126
 127         SNIC_BUG_ON(pa == 0);
 128         rqi->sge_va = (ulong) buf;
 129
 130         snic_report_tgt_init(rqi->req,
 131                              snic->config.hid,
 132                              buf,
 133                              buf_len,
 134                              pa,
 135                              (ulong)rqi);
 136
 137         snic_handle_untagged_req(snic, rqi);
 138
 139         ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
 140         if (ret) {
 141                 pci_unmap_single(snic->pdev, pa, buf_len, PCI_DMA_FROMDEVICE);
 142                 kfree(buf);
 143                 rqi->sge_va = 0;
 144                 snic_release_untagged_req(snic, rqi);
 145                 SNIC_HOST_ERR(snic->shost, "Queuing Report Tgts Failed.\n");
 146
 147                 goto error;
 148         }
 149
 150         SNIC_DISC_DBG(snic->shost, "Report Targets Issued.\n");
 151
 152         return ret;
 153
 154 error:
 155         SNIC_HOST_ERR(snic->shost,
 156                       "Queuing Report Targets Failed, err = %d\n",
 157                       ret);
 158         return ret;
 159 } /* end of snic_queue_report_tgt_req */
 160
 161 /* call into SML */
 162 static void
 163 snic_scsi_scan_tgt(struct work_struct *work)
 164 {
 165         struct snic_tgt *tgt = container_of(work, struct snic_tgt, scan_work);
 166         struct Scsi_Host *shost = dev_to_shost(&tgt->dev);
 167         unsigned long flags;
 168
 169         SNIC_HOST_INFO(shost, "Scanning Target id 0x%x\n", tgt->id);
 170         scsi_scan_target(&tgt->dev,
 171                          tgt->channel,
 172                          tgt->scsi_tgt_id,
 173                          SCAN_WILD_CARD,
 174                          1);
 175
 176         spin_lock_irqsave(shost->host_lock, flags);
 177         tgt->flags &= ~SNIC_TGT_SCAN_PENDING;
 178         spin_unlock_irqrestore(shost->host_lock, flags);
 179 } /* end of snic_scsi_scan_tgt */
 180
 181 /*
 182  * snic_tgt_lookup :
 183  */
 184 static struct snic_tgt *
 185 snic_tgt_lookup(struct snic *snic, struct snic_tgt_id *tgtid)
 186 {
 187         struct list_head *cur, *nxt;
 188         struct snic_tgt *tgt = NULL;
 189
 190         list_for_each_safe(cur, nxt, &snic->disc.tgt_list) {
 191                 tgt = list_entry(cur, struct snic_tgt, list);
 192                 if (tgt->id == le32_to_cpu(tgtid->tgt_id))
 193                         return tgt;
 194                 tgt = NULL;
 195         }
 196
 197         return tgt;
 198 } /* end of snic_tgt_lookup */
 199
 200 /*
 201  * snic_tgt_dev_release : Called on dropping last ref for snic_tgt object
 202  */
 203 void
 204 snic_tgt_dev_release(struct device *dev)
 205 {
 206         struct snic_tgt *tgt = dev_to_tgt(dev);
 207
 208         SNIC_HOST_INFO(snic_tgt_to_shost(tgt),
 209                        "Target Device ID %d (%s) Permanently Deleted.\n",
 210                        tgt->id,
 211                        dev_name(dev));
 212
 213         SNIC_BUG_ON(!list_empty(&tgt->list));
 214         kfree(tgt);
 215 }
 216
 217 /*
 218  * snic_tgt_del : work function to delete snic_tgt
 219  */
 220 static void
 221 snic_tgt_del(struct work_struct *work)
 222 {
 223         struct snic_tgt *tgt = container_of(work, struct snic_tgt, del_work);
 224         struct Scsi_Host *shost = snic_tgt_to_shost(tgt);
 225
 226         if (tgt->flags & SNIC_TGT_SCAN_PENDING)
 227                 scsi_flush_work(shost);
 228
 229         /* Block IOs on child devices, stops new IOs */
 230         scsi_target_block(&tgt->dev);
 231
 232         /* Cleanup IOs */
 233         snic_tgt_scsi_abort_io(tgt);
 234
 235         /* Unblock IOs now, to flush if there are any. */
 236         scsi_target_unblock(&tgt->dev, SDEV_TRANSPORT_OFFLINE);
 237
 238         /* Delete SCSI Target and sdevs */
 239         scsi_remove_target(&tgt->dev);  /* ?? */
 240         device_del(&tgt->dev);
 241         put_device(&tgt->dev);
 242 } /* end of snic_tgt_del */
 243
 244 /* snic_tgt_create: checks for existence of snic_tgt, if it doesn't
 245  * it creates one.
 246  */
 247 static struct snic_tgt *
 248 snic_tgt_create(struct snic *snic, struct snic_tgt_id *tgtid)
 249 {
 250         struct snic_tgt *tgt = NULL;
 251         unsigned long flags;
 252         int ret;
 253
 254         tgt = snic_tgt_lookup(snic, tgtid);
 255         if (tgt) {
 256                 /* update the information if required */
 257                 return tgt;
 258         }
 259
 260         tgt = kzalloc(sizeof(*tgt), GFP_KERNEL);
 261         if (!tgt) {
 262                 SNIC_HOST_ERR(snic->shost, "Failure to allocate snic_tgt.\n");
 263                 ret = -ENOMEM;
 264
 265                 return tgt;
 266         }
 267
 268         INIT_LIST_HEAD(&tgt->list);
 269         tgt->id = le32_to_cpu(tgtid->tgt_id);
 270         tgt->channel = 0;
 271
 272         SNIC_BUG_ON(le16_to_cpu(tgtid->tgt_type) > SNIC_TGT_SAN);
 273         tgt->tdata.typ = le16_to_cpu(tgtid->tgt_type);
 274
 275         /*
 276          * Plugging into SML Device Tree
 277          */
 278         tgt->tdata.disc_id = 0;
 279         tgt->state = SNIC_TGT_STAT_INIT;
 280         device_initialize(&tgt->dev);
 281         tgt->dev.parent = get_device(&snic->shost->shost_gendev);
 282         tgt->dev.release = snic_tgt_dev_release;
 283         INIT_WORK(&tgt->scan_work, snic_scsi_scan_tgt);
 284         INIT_WORK(&tgt->del_work, snic_tgt_del);
 285         switch (tgt->tdata.typ) {
 286         case SNIC_TGT_DAS:
 287                 dev_set_name(&tgt->dev, "snic_das_tgt:%d:%d-%d",
 288                              snic->shost->host_no, tgt->channel, tgt->id);
 289                 break;
 290
 291         case SNIC_TGT_SAN:
 292                 dev_set_name(&tgt->dev, "snic_san_tgt:%d:%d-%d",
 293                              snic->shost->host_no, tgt->channel, tgt->id);
 294                 break;
 295
 296         default:
 297                 SNIC_HOST_INFO(snic->shost, "Target type Unknown Detected.\n");
 298                 dev_set_name(&tgt->dev, "snic_das_tgt:%d:%d-%d",
 299                              snic->shost->host_no, tgt->channel, tgt->id);
 300                 break;
 301         }
 302
 303         spin_lock_irqsave(snic->shost->host_lock, flags);
 304         list_add_tail(&tgt->list, &snic->disc.tgt_list);
 305         tgt->scsi_tgt_id = snic->disc.nxt_tgt_id++;
 306         tgt->state = SNIC_TGT_STAT_ONLINE;
 307         spin_unlock_irqrestore(snic->shost->host_lock, flags);
 308
 309         SNIC_HOST_INFO(snic->shost,
 310                        "Tgt %d, type = %s detected. Adding..\n",
 311                        tgt->id, snic_tgt_type_to_str(tgt->tdata.typ));
 312
 313         ret = device_add(&tgt->dev);
 314         if (ret) {
 315                 SNIC_HOST_ERR(snic->shost,
 316                               "Snic Tgt: device_add, with err = %d\n",
 317                               ret);
 318
 319                 put_device(&snic->shost->shost_gendev);
 320                 kfree(tgt);
 321                 tgt = NULL;
 322
 323                 return tgt;
 324         }
 325
 326         SNIC_HOST_INFO(snic->shost, "Scanning %s.\n", dev_name(&tgt->dev));
 327
 328         scsi_queue_work(snic->shost, &tgt->scan_work);
 329
 330         return tgt;
 331 } /* end of snic_tgt_create */
 332
 333 /* Handler for discovery */
 334 void
 335 snic_handle_tgt_disc(struct work_struct *work)
 336 {
 337         struct snic *snic = container_of(work, struct snic, tgt_work);
 338         struct snic_tgt_id *tgtid = NULL;
 339         struct snic_tgt *tgt = NULL;
 340         unsigned long flags;
 341         int i;
 342
 343         spin_lock_irqsave(&snic->snic_lock, flags);
 344         if (snic->in_remove) {
 345                 spin_unlock_irqrestore(&snic->snic_lock, flags);
 346                 kfree(snic->disc.rtgt_info);
 347
 348                 return;
 349         }
 350         spin_unlock_irqrestore(&snic->snic_lock, flags);
 351
 352         mutex_lock(&snic->disc.mutex);
 353         /* Discover triggered during disc in progress */
 354         if (snic->disc.req_cnt) {
 355                 snic->disc.state = SNIC_DISC_DONE;
 356                 snic->disc.req_cnt = 0;
 357                 mutex_unlock(&snic->disc.mutex);
 358                 kfree(snic->disc.rtgt_info);
 359                 snic->disc.rtgt_info = NULL;
 360
 361                 SNIC_HOST_INFO(snic->shost, "tgt_disc: Discovery restart.\n");
 362                 /* Start Discovery Again */
 363                 snic_disc_start(snic);
 364
 365                 return;
 366         }
 367
 368         tgtid = (struct snic_tgt_id *)snic->disc.rtgt_info;
 369
 370         SNIC_BUG_ON(snic->disc.rtgt_cnt == 0 || tgtid == NULL);
 371
 372         for (i = 0; i < snic->disc.rtgt_cnt; i++) {
 373                 tgt = snic_tgt_create(snic, &tgtid[i]);
 374                 if (!tgt) {
 375                         int buf_sz = snic->disc.rtgt_cnt * sizeof(*tgtid);
 376
 377                         SNIC_HOST_ERR(snic->shost, "Failed to create tgt.\n");
 378                         snic_hex_dump("rpt_tgt_rsp", (char *)tgtid, buf_sz);
 379                         break;
 380                 }
 381         }
 382
 383         snic->disc.rtgt_info = NULL;
 384         snic->disc.state = SNIC_DISC_DONE;
 385         mutex_unlock(&snic->disc.mutex);
 386
 387         SNIC_HOST_INFO(snic->shost, "Discovery Completed.\n");
 388
 389         kfree(tgtid);
 390 } /* end of snic_handle_tgt_disc */
 391
 392
 393 int
 394 snic_report_tgt_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
 395 {
 396
 397         u8 typ, cmpl_stat;
 398         u32 cmnd_id, hid, tgt_cnt = 0;
 399         ulong ctx;
 400         struct snic_req_info *rqi = NULL;
 401         struct snic_tgt_id *tgtid;
 402         int i, ret = 0;
 403
 404         snic_io_hdr_dec(&fwreq->hdr, &typ, &cmpl_stat, &cmnd_id, &hid, &ctx);
 405         rqi = (struct snic_req_info *) ctx;
 406         tgtid = (struct snic_tgt_id *) rqi->sge_va;
 407
 408         tgt_cnt = le32_to_cpu(fwreq->u.rpt_tgts_cmpl.tgt_cnt);
 409         if (tgt_cnt == 0) {
 410                 SNIC_HOST_ERR(snic->shost, "No Targets Found on this host.\n");
 411                 ret = 1;
 412
 413                 goto end;
 414         }
 415
 416         /* printing list of targets here */
 417         SNIC_HOST_INFO(snic->shost, "Target Count = %d\n", tgt_cnt);
 418
 419         SNIC_BUG_ON(tgt_cnt > snic->fwinfo.max_tgts);
 420
 421         for (i = 0; i < tgt_cnt; i++)
 422                 SNIC_HOST_INFO(snic->shost,
 423                                "Tgt id = 0x%x\n",
 424                                le32_to_cpu(tgtid[i].tgt_id));
 425
 426         /*
 427          * Queue work for further processing,
 428          * Response Buffer Memory is freed after creating targets
 429          */
 430         snic->disc.rtgt_cnt = tgt_cnt;
 431         snic->disc.rtgt_info = (u8 *) tgtid;
 432         queue_work(snic_glob->event_q, &snic->tgt_work);
 433         ret = 0;
 434
 435 end:
 436         /* Unmap Response Buffer */
 437         snic_pci_unmap_rsp_buf(snic, rqi);
 438         if (ret)
 439                 kfree(tgtid);
 440
 441         rqi->sge_va = 0;
 442         snic_release_untagged_req(snic, rqi);
 443
 444         return ret;
 445 } /* end of snic_report_tgt_cmpl_handler */
 446
 447 /* Discovery init fn */
 448 void
 449 snic_disc_init(struct snic_disc *disc)
 450 {
 451         INIT_LIST_HEAD(&disc->tgt_list);
 452         mutex_init(&disc->mutex);
 453         disc->disc_id = 0;
 454         disc->nxt_tgt_id = 0;
 455         disc->state = SNIC_DISC_INIT;
 456         disc->req_cnt = 0;
 457         disc->rtgt_cnt = 0;
 458         disc->rtgt_info = NULL;
 459         disc->cb = NULL;
 460 } /* end of snic_disc_init */
 461
 462 /* Discovery, uninit fn */
 463 void
 464 snic_disc_term(struct snic *snic)
 465 {
 466         struct snic_disc *disc = &snic->disc;
 467
 468         mutex_lock(&disc->mutex);
 469         if (disc->req_cnt) {
 470                 disc->req_cnt = 0;
 471                 SNIC_SCSI_DBG(snic->shost, "Terminating Discovery.\n");
 472         }
 473         mutex_unlock(&disc->mutex);
 474 }
 475
 476 /*
 477  * snic_disc_start: Discovery Start ...
 478  */
 479 int
 480 snic_disc_start(struct snic *snic)
 481 {
 482         struct snic_disc *disc = &snic->disc;
 483         int ret = 0;
 484
 485         SNIC_SCSI_DBG(snic->shost, "Discovery Start.\n");
 486
 487         mutex_lock(&disc->mutex);
 488         if (disc->state == SNIC_DISC_PENDING) {
 489                 disc->req_cnt++;
 490                 mutex_unlock(&disc->mutex);
 491
 492                 return ret;
 493         }
 494         disc->state = SNIC_DISC_PENDING;
 495         mutex_unlock(&disc->mutex);
 496
 497         ret = snic_queue_report_tgt_req(snic);
 498         if (ret)
 499                 SNIC_HOST_INFO(snic->shost, "Discovery Failed, err=%d.\n", ret);
 500
 501         return ret;
 502 } /* end of snic_disc_start */
 503
 504 /*
 505  * snic_disc_work :
 506  */
 507 void
 508 snic_handle_disc(struct work_struct *work)
 509 {
 510         struct snic *snic = container_of(work, struct snic, disc_work);
 511         int ret = 0;
 512
 513         SNIC_HOST_INFO(snic->shost, "disc_work: Discovery\n");
 514
 515         ret = snic_disc_start(snic);
 516         if (ret)
 517                 goto disc_err;
 518
 519 disc_err:
 520         SNIC_HOST_ERR(snic->shost,
 521                       "disc_work: Discovery Failed w/ err = %d\n",
 522                       ret);
 523 } /* end of snic_disc_work */
 524
 525 /*
 526  * snic_tgt_del_all : cleanup all snic targets
 527  * Called on unbinding the interface
 528  */
 529 void
 530 snic_tgt_del_all(struct snic *snic)
 531 {
 532         struct snic_tgt *tgt = NULL;
 533         struct list_head *cur, *nxt;
 534         unsigned long flags;
 535
 536         mutex_lock(&snic->disc.mutex);
 537         spin_lock_irqsave(snic->shost->host_lock, flags);
 538
 539         list_for_each_safe(cur, nxt, &snic->disc.tgt_list) {
 540                 tgt = list_entry(cur, struct snic_tgt, list);
 541                 tgt->state = SNIC_TGT_STAT_DEL;
 542                 list_del_init(&tgt->list);
 543                 SNIC_HOST_INFO(snic->shost, "Tgt %d q'ing for del\n", tgt->id);
 544                 queue_work(snic_glob->event_q, &tgt->del_work);
 545                 tgt = NULL;
 546         }
 547         spin_unlock_irqrestore(snic->shost->host_lock, flags);
 548
 549         scsi_flush_work(snic->shost);
 550         mutex_unlock(&snic->disc.mutex);
 551 } /* end of snic_tgt_del_all */