drivers/target/tcm_fc/tfc_cmd.c

   1 /*
   2  * Copyright (c) 2010 Cisco Systems, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 /* XXX TBD some includes may be extraneous */
  19
  20 #include <linux/module.h>
  21 #include <linux/moduleparam.h>
  22 #include <generated/utsrelease.h>
  23 #include <linux/utsname.h>
  24 #include <linux/init.h>
  25 #include <linux/slab.h>
  26 #include <linux/kthread.h>
  27 #include <linux/types.h>
  28 #include <linux/string.h>
  29 #include <linux/configfs.h>
  30 #include <linux/ctype.h>
  31 #include <linux/hash.h>
  32 #include <asm/unaligned.h>
  33 #include <scsi/scsi.h>
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi_device.h>
  36 #include <scsi/scsi_cmnd.h>
  37 #include <scsi/scsi_tcq.h>
  38 #include <scsi/libfc.h>
  39 #include <scsi/fc_encode.h>
  40
  41 #include <target/target_core_base.h>
  42 #include <target/target_core_transport.h>
  43 #include <target/target_core_fabric_ops.h>
  44 #include <target/target_core_device.h>
  45 #include <target/target_core_tpg.h>
  46 #include <target/target_core_configfs.h>
  47 #include <target/target_core_tmr.h>
  48 #include <target/configfs_macros.h>
  49
  50 #include "tcm_fc.h"
  51
  52 /*
  53  * Dump cmd state for debugging.
  54  */
  55 void ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
  56 {
  57         struct fc_exch *ep;
  58         struct fc_seq *sp;
  59         struct se_cmd *se_cmd;
  60         struct scatterlist *sg;
  61         int count;
  62
  63         se_cmd = &cmd->se_cmd;
  64         pr_debug("%s: cmd %p state %d sess %p seq %p se_cmd %p\n",
  65                 caller, cmd, cmd->state, cmd->sess, cmd->seq, se_cmd);
  66         pr_debug("%s: cmd %p cdb %p\n",
  67                 caller, cmd, cmd->cdb);
  68         pr_debug("%s: cmd %p lun %d\n", caller, cmd, cmd->lun);
  69
  70         pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
  71                 caller, cmd, se_cmd->t_data_nents,
  72                se_cmd->data_length, se_cmd->se_cmd_flags);
  73
  74         for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
  75                 pr_debug("%s: cmd %p sg %p page %p "
  76                         "len 0x%x off 0x%x\n",
  77                         caller, cmd, sg,
  78                         sg_page(sg), sg->length, sg->offset);
  79
  80         sp = cmd->seq;
  81         if (sp) {
  82                 ep = fc_seq_exch(sp);
  83                 pr_debug("%s: cmd %p sid %x did %x "
  84                         "ox_id %x rx_id %x seq_id %x e_stat %x\n",
  85                         caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
  86                         sp->id, ep->esb_stat);
  87         }
  88         print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE,
  89                 16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0);
  90 }
  91
  92 static void ft_queue_cmd(struct ft_sess *sess, struct ft_cmd *cmd)
  93 {
  94         struct ft_tpg *tpg = sess->tport->tpg;
  95         struct se_queue_obj *qobj = &tpg->qobj;
  96         unsigned long flags;
  97
  98         qobj = &sess->tport->tpg->qobj;
  99         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
 100         list_add_tail(&cmd->se_req.qr_list, &qobj->qobj_list);
 101         atomic_inc(&qobj->queue_cnt);
 102         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
 103
 104         wake_up_process(tpg->thread);
 105 }
 106
 107 static struct ft_cmd *ft_dequeue_cmd(struct se_queue_obj *qobj)
 108 {
 109         unsigned long flags;
 110         struct se_queue_req *qr;
 111
 112         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
 113         if (list_empty(&qobj->qobj_list)) {
 114                 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
 115                 return NULL;
 116         }
 117         qr = list_first_entry(&qobj->qobj_list, struct se_queue_req, qr_list);
 118         list_del(&qr->qr_list);
 119         atomic_dec(&qobj->queue_cnt);
 120         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
 121         return container_of(qr, struct ft_cmd, se_req);
 122 }
 123
 124 static void ft_free_cmd(struct ft_cmd *cmd)
 125 {
 126         struct fc_frame *fp;
 127         struct fc_lport *lport;
 128
 129         if (!cmd)
 130                 return;
 131         fp = cmd->req_frame;
 132         lport = fr_dev(fp);
 133         if (fr_seq(fp))
 134                 lport->tt.seq_release(fr_seq(fp));
 135         fc_frame_free(fp);
 136         ft_sess_put(cmd->sess); /* undo get from lookup at recv */
 137         kfree(cmd);
 138 }
 139
 140 void ft_release_cmd(struct se_cmd *se_cmd)
 141 {
 142         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 143
 144         ft_free_cmd(cmd);
 145 }
 146
 147 void ft_check_stop_free(struct se_cmd *se_cmd)
 148 {
 149         transport_generic_free_cmd(se_cmd, 0, 0);
 150 }
 151
 152 /*
 153  * Send response.
 154  */
 155 int ft_queue_status(struct se_cmd *se_cmd)
 156 {
 157         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 158         struct fc_frame *fp;
 159         struct fcp_resp_with_ext *fcp;
 160         struct fc_lport *lport;
 161         struct fc_exch *ep;
 162         size_t len;
 163
 164         ft_dump_cmd(cmd, __func__);
 165         ep = fc_seq_exch(cmd->seq);
 166         lport = ep->lp;
 167         len = sizeof(*fcp) + se_cmd->scsi_sense_length;
 168         fp = fc_frame_alloc(lport, len);
 169         if (!fp) {
 170                 /* XXX shouldn't just drop it - requeue and retry? */
 171                 return 0;
 172         }
 173         fcp = fc_frame_payload_get(fp, len);
 174         memset(fcp, 0, len);
 175         fcp->resp.fr_status = se_cmd->scsi_status;
 176
 177         len = se_cmd->scsi_sense_length;
 178         if (len) {
 179                 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL;
 180                 fcp->ext.fr_sns_len = htonl(len);
 181                 memcpy((fcp + 1), se_cmd->sense_buffer, len);
 182         }
 183
 184         /*
 185          * Test underflow and overflow with one mask.  Usually both are off.
 186          * Bidirectional commands are not handled yet.
 187          */
 188         if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) {
 189                 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
 190                         fcp->resp.fr_flags |= FCP_RESID_OVER;
 191                 else
 192                         fcp->resp.fr_flags |= FCP_RESID_UNDER;
 193                 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
 194         }
 195
 196         /*
 197          * Send response.
 198          */
 199         cmd->seq = lport->tt.seq_start_next(cmd->seq);
 200         fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
 201                        FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0);
 202
 203         lport->tt.seq_send(lport, cmd->seq, fp);
 204         lport->tt.exch_done(cmd->seq);
 205         return 0;
 206 }
 207
 208 int ft_write_pending_status(struct se_cmd *se_cmd)
 209 {
 210         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 211
 212         return cmd->write_data_len != se_cmd->data_length;
 213 }
 214
 215 /*
 216  * Send TX_RDY (transfer ready).
 217  */
 218 int ft_write_pending(struct se_cmd *se_cmd)
 219 {
 220         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 221         struct fc_frame *fp;
 222         struct fcp_txrdy *txrdy;
 223         struct fc_lport *lport;
 224         struct fc_exch *ep;
 225         struct fc_frame_header *fh;
 226         u32 f_ctl;
 227
 228         ft_dump_cmd(cmd, __func__);
 229
 230         ep = fc_seq_exch(cmd->seq);
 231         lport = ep->lp;
 232         fp = fc_frame_alloc(lport, sizeof(*txrdy));
 233         if (!fp)
 234                 return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
 235
 236         txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
 237         memset(txrdy, 0, sizeof(*txrdy));
 238         txrdy->ft_burst_len = htonl(se_cmd->data_length);
 239
 240         cmd->seq = lport->tt.seq_start_next(cmd->seq);
 241         fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
 242                        FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
 243
 244         fh = fc_frame_header_get(fp);
 245         f_ctl = ntoh24(fh->fh_f_ctl);
 246
 247         /* Only if it is 'Exchange Responder' */
 248         if (f_ctl & FC_FC_EX_CTX) {
 249                 /* Target is 'exchange responder' and sending XFER_READY
 250                  * to 'exchange initiator (initiator)'
 251                  */
 252                 if ((ep->xid <= lport->lro_xid) &&
 253                     (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
 254                         if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
 255                                 /*
 256                                  * cmd may have been broken up into multiple
 257                                  * tasks. Link their sgs together so we can
 258                                  * operate on them all at once.
 259                                  */
 260                                 transport_do_task_sg_chain(se_cmd);
 261                                 cmd->sg = se_cmd->t_tasks_sg_chained;
 262                                 cmd->sg_cnt =
 263                                         se_cmd->t_tasks_sg_chained_no;
 264                         }
 265                         if (cmd->sg && lport->tt.ddp_target(lport, ep->xid,
 266                                                             cmd->sg,
 267                                                             cmd->sg_cnt))
 268                                 cmd->was_ddp_setup = 1;
 269                 }
 270         }
 271         lport->tt.seq_send(lport, cmd->seq, fp);
 272         return 0;
 273 }
 274
 275 u32 ft_get_task_tag(struct se_cmd *se_cmd)
 276 {
 277         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 278
 279         return fc_seq_exch(cmd->seq)->rxid;
 280 }
 281
 282 int ft_get_cmd_state(struct se_cmd *se_cmd)
 283 {
 284         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 285
 286         return cmd->state;
 287 }
 288
 289 int ft_is_state_remove(struct se_cmd *se_cmd)
 290 {
 291         return 0;       /* XXX TBD */
 292 }
 293
 294 /*
 295  * FC sequence response handler for follow-on sequences (data) and aborts.
 296  */
 297 static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
 298 {
 299         struct ft_cmd *cmd = arg;
 300         struct fc_frame_header *fh;
 301
 302         if (IS_ERR(fp)) {
 303                 /* XXX need to find cmd if queued */
 304                 cmd->se_cmd.t_state = TRANSPORT_REMOVE;
 305                 cmd->seq = NULL;
 306                 transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
 307                 return;
 308         }
 309
 310         fh = fc_frame_header_get(fp);
 311
 312         switch (fh->fh_r_ctl) {
 313         case FC_RCTL_DD_SOL_DATA:       /* write data */
 314                 ft_recv_write_data(cmd, fp);
 315                 break;
 316         case FC_RCTL_DD_UNSOL_CTL:      /* command */
 317         case FC_RCTL_DD_SOL_CTL:        /* transfer ready */
 318         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
 319         default:
 320                 pr_debug("%s: unhandled frame r_ctl %x\n",
 321                        __func__, fh->fh_r_ctl);
 322                 ft_invl_hw_context(cmd);
 323                 fc_frame_free(fp);
 324                 transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
 325                 break;
 326         }
 327 }
 328
 329 /*
 330  * Send a FCP response including SCSI status and optional FCP rsp_code.
 331  * status is SAM_STAT_GOOD (zero) iff code is valid.
 332  * This is used in error cases, such as allocation failures.
 333  */
 334 static void ft_send_resp_status(struct fc_lport *lport,
 335                                 const struct fc_frame *rx_fp,
 336                                 u32 status, enum fcp_resp_rsp_codes code)
 337 {
 338         struct fc_frame *fp;
 339         struct fc_seq *sp;
 340         const struct fc_frame_header *fh;
 341         size_t len;
 342         struct fcp_resp_with_ext *fcp;
 343         struct fcp_resp_rsp_info *info;
 344
 345         fh = fc_frame_header_get(rx_fp);
 346         pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
 347                   ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
 348         len = sizeof(*fcp);
 349         if (status == SAM_STAT_GOOD)
 350                 len += sizeof(*info);
 351         fp = fc_frame_alloc(lport, len);
 352         if (!fp)
 353                 return;
 354         fcp = fc_frame_payload_get(fp, len);
 355         memset(fcp, 0, len);
 356         fcp->resp.fr_status = status;
 357         if (status == SAM_STAT_GOOD) {
 358                 fcp->ext.fr_rsp_len = htonl(sizeof(*info));
 359                 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL;
 360                 info = (struct fcp_resp_rsp_info *)(fcp + 1);
 361                 info->rsp_code = code;
 362         }
 363
 364         fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
 365         sp = fr_seq(fp);
 366         if (sp)
 367                 lport->tt.seq_send(lport, sp, fp);
 368         else
 369                 lport->tt.frame_send(lport, fp);
 370 }
 371
 372 /*
 373  * Send error or task management response.
 374  */
 375 static void ft_send_resp_code(struct ft_cmd *cmd,
 376                               enum fcp_resp_rsp_codes code)
 377 {
 378         ft_send_resp_status(cmd->sess->tport->lport,
 379                             cmd->req_frame, SAM_STAT_GOOD, code);
 380 }
 381
 382
 383 /*
 384  * Send error or task management response.
 385  * Always frees the cmd and associated state.
 386  */
 387 static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
 388                                       enum fcp_resp_rsp_codes code)
 389 {
 390         ft_send_resp_code(cmd, code);
 391         ft_free_cmd(cmd);
 392 }
 393
 394 /*
 395  * Handle Task Management Request.
 396  */
 397 static void ft_send_tm(struct ft_cmd *cmd)
 398 {
 399         struct se_tmr_req *tmr;
 400         struct fcp_cmnd *fcp;
 401         struct ft_sess *sess;
 402         u8 tm_func;
 403
 404         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
 405
 406         switch (fcp->fc_tm_flags) {
 407         case FCP_TMF_LUN_RESET:
 408                 tm_func = TMR_LUN_RESET;
 409                 break;
 410         case FCP_TMF_TGT_RESET:
 411                 tm_func = TMR_TARGET_WARM_RESET;
 412                 break;
 413         case FCP_TMF_CLR_TASK_SET:
 414                 tm_func = TMR_CLEAR_TASK_SET;
 415                 break;
 416         case FCP_TMF_ABT_TASK_SET:
 417                 tm_func = TMR_ABORT_TASK_SET;
 418                 break;
 419         case FCP_TMF_CLR_ACA:
 420                 tm_func = TMR_CLEAR_ACA;
 421                 break;
 422         default:
 423                 /*
 424                  * FCP4r01 indicates having a combination of
 425                  * tm_flags set is invalid.
 426                  */
 427                 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
 428                 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
 429                 return;
 430         }
 431
 432         pr_debug("alloc tm cmd fn %d\n", tm_func);
 433         tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
 434         if (!tmr) {
 435                 pr_debug("alloc failed\n");
 436                 ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
 437                 return;
 438         }
 439         cmd->se_cmd.se_tmr_req = tmr;
 440
 441         switch (fcp->fc_tm_flags) {
 442         case FCP_TMF_LUN_RESET:
 443                 cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
 444                 if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
 445                         /*
 446                          * Make sure to clean up newly allocated TMR request
 447                          * since "unable to  handle TMR request because failed
 448                          * to get to LUN"
 449                          */
 450                         pr_debug("Failed to get LUN for TMR func %d, "
 451                                   "se_cmd %p, unpacked_lun %d\n",
 452                                   tm_func, &cmd->se_cmd, cmd->lun);
 453                         ft_dump_cmd(cmd, __func__);
 454                         sess = cmd->sess;
 455                         transport_send_check_condition_and_sense(&cmd->se_cmd,
 456                                 cmd->se_cmd.scsi_sense_reason, 0);
 457                         transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
 458                         ft_sess_put(sess);
 459                         return;
 460                 }
 461                 break;
 462         case FCP_TMF_TGT_RESET:
 463         case FCP_TMF_CLR_TASK_SET:
 464         case FCP_TMF_ABT_TASK_SET:
 465         case FCP_TMF_CLR_ACA:
 466                 break;
 467         default:
 468                 return;
 469         }
 470         transport_generic_handle_tmr(&cmd->se_cmd);
 471 }
 472
 473 /*
 474  * Send status from completed task management request.
 475  */
 476 int ft_queue_tm_resp(struct se_cmd *se_cmd)
 477 {
 478         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
 479         struct se_tmr_req *tmr = se_cmd->se_tmr_req;
 480         enum fcp_resp_rsp_codes code;
 481
 482         switch (tmr->response) {
 483         case TMR_FUNCTION_COMPLETE:
 484                 code = FCP_TMF_CMPL;
 485                 break;
 486         case TMR_LUN_DOES_NOT_EXIST:
 487                 code = FCP_TMF_INVALID_LUN;
 488                 break;
 489         case TMR_FUNCTION_REJECTED:
 490                 code = FCP_TMF_REJECTED;
 491                 break;
 492         case TMR_TASK_DOES_NOT_EXIST:
 493         case TMR_TASK_STILL_ALLEGIANT:
 494         case TMR_TASK_FAILOVER_NOT_SUPPORTED:
 495         case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
 496         case TMR_FUNCTION_AUTHORIZATION_FAILED:
 497         default:
 498                 code = FCP_TMF_FAILED;
 499                 break;
 500         }
 501         pr_debug("tmr fn %d resp %d fcp code %d\n",
 502                   tmr->function, tmr->response, code);
 503         ft_send_resp_code(cmd, code);
 504         return 0;
 505 }
 506
 507 /*
 508  * Handle incoming FCP command.
 509  */
 510 static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
 511 {
 512         struct ft_cmd *cmd;
 513         struct fc_lport *lport = sess->tport->lport;
 514
 515         cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
 516         if (!cmd)
 517                 goto busy;
 518         cmd->sess = sess;
 519         cmd->seq = lport->tt.seq_assign(lport, fp);
 520         if (!cmd->seq) {
 521                 kfree(cmd);
 522                 goto busy;
 523         }
 524         cmd->req_frame = fp;            /* hold frame during cmd */
 525         ft_queue_cmd(sess, cmd);
 526         return;
 527
 528 busy:
 529         pr_debug("cmd or seq allocation failure - sending BUSY\n");
 530         ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
 531         fc_frame_free(fp);
 532         ft_sess_put(sess);              /* undo get from lookup */
 533 }
 534
 535
 536 /*
 537  * Handle incoming FCP frame.
 538  * Caller has verified that the frame is type FCP.
 539  */
 540 void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
 541 {
 542         struct fc_frame_header *fh = fc_frame_header_get(fp);
 543
 544         switch (fh->fh_r_ctl) {
 545         case FC_RCTL_DD_UNSOL_CMD:      /* command */
 546                 ft_recv_cmd(sess, fp);
 547                 break;
 548         case FC_RCTL_DD_SOL_DATA:       /* write data */
 549         case FC_RCTL_DD_UNSOL_CTL:
 550         case FC_RCTL_DD_SOL_CTL:
 551         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
 552         case FC_RCTL_ELS4_REQ:          /* SRR, perhaps */
 553         default:
 554                 pr_debug("%s: unhandled frame r_ctl %x\n",
 555                        __func__, fh->fh_r_ctl);
 556                 fc_frame_free(fp);
 557                 ft_sess_put(sess);      /* undo get from lookup */
 558                 break;
 559         }
 560 }
 561
 562 /*
 563  * Send new command to target.
 564  */
 565 static void ft_send_cmd(struct ft_cmd *cmd)
 566 {
 567         struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
 568         struct se_cmd *se_cmd;
 569         struct fcp_cmnd *fcp;
 570         int data_dir;
 571         u32 data_len;
 572         int task_attr;
 573         int ret;
 574
 575         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
 576         if (!fcp)
 577                 goto err;
 578
 579         if (fcp->fc_flags & FCP_CFL_LEN_MASK)
 580                 goto err;               /* not handling longer CDBs yet */
 581
 582         if (fcp->fc_tm_flags) {
 583                 task_attr = FCP_PTA_SIMPLE;
 584                 data_dir = DMA_NONE;
 585                 data_len = 0;
 586         } else {
 587                 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
 588                 case 0:
 589                         data_dir = DMA_NONE;
 590                         break;
 591                 case FCP_CFL_RDDATA:
 592                         data_dir = DMA_FROM_DEVICE;
 593                         break;
 594                 case FCP_CFL_WRDATA:
 595                         data_dir = DMA_TO_DEVICE;
 596                         break;
 597                 case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
 598                         goto err;       /* TBD not supported by tcm_fc yet */
 599                 }
 600                 /*
 601                  * Locate the SAM Task Attr from fc_pri_ta
 602                  */
 603                 switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
 604                 case FCP_PTA_HEADQ:
 605                         task_attr = MSG_HEAD_TAG;
 606                         break;
 607                 case FCP_PTA_ORDERED:
 608                         task_attr = MSG_ORDERED_TAG;
 609                         break;
 610                 case FCP_PTA_ACA:
 611                         task_attr = MSG_ACA_TAG;
 612                         break;
 613                 case FCP_PTA_SIMPLE: /* Fallthrough */
 614                 default:
 615                         task_attr = MSG_SIMPLE_TAG;
 616                 }
 617
 618
 619                 task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
 620                 data_len = ntohl(fcp->fc_dl);
 621                 cmd->cdb = fcp->fc_cdb;
 622         }
 623
 624         se_cmd = &cmd->se_cmd;
 625         /*
 626          * Initialize struct se_cmd descriptor from target_core_mod
 627          * infrastructure
 628          */
 629         transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
 630                               data_len, data_dir, task_attr,
 631                               &cmd->ft_sense_buffer[0]);
 632         /*
 633          * Check for FCP task management flags
 634          */
 635         if (fcp->fc_tm_flags) {
 636                 ft_send_tm(cmd);
 637                 return;
 638         }
 639
 640         fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
 641
 642         cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
 643         ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
 644         if (ret < 0) {
 645                 ft_dump_cmd(cmd, __func__);
 646                 transport_send_check_condition_and_sense(&cmd->se_cmd,
 647                         cmd->se_cmd.scsi_sense_reason, 0);
 648                 return;
 649         }
 650
 651         ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);
 652
 653         pr_debug("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
 654         ft_dump_cmd(cmd, __func__);
 655
 656         if (ret == -ENOMEM) {
 657                 transport_send_check_condition_and_sense(se_cmd,
 658                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 659                 transport_generic_free_cmd(se_cmd, 0, 0);
 660                 return;
 661         }
 662         if (ret == -EINVAL) {
 663                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
 664                         ft_queue_status(se_cmd);
 665                 else
 666                         transport_send_check_condition_and_sense(se_cmd,
 667                                         se_cmd->scsi_sense_reason, 0);
 668                 transport_generic_free_cmd(se_cmd, 0, 0);
 669                 return;
 670         }
 671         transport_generic_handle_cdb(se_cmd);
 672         return;
 673
 674 err:
 675         ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
 676 }
 677
 678 /*
 679  * Handle request in the command thread.
 680  */
 681 static void ft_exec_req(struct ft_cmd *cmd)
 682 {
 683         pr_debug("cmd state %x\n", cmd->state);
 684         switch (cmd->state) {
 685         case FC_CMD_ST_NEW:
 686                 ft_send_cmd(cmd);
 687                 break;
 688         default:
 689                 break;
 690         }
 691 }
 692
 693 /*
 694  * Processing thread.
 695  * Currently one thread per tpg.
 696  */
 697 int ft_thread(void *arg)
 698 {
 699         struct ft_tpg *tpg = arg;
 700         struct se_queue_obj *qobj = &tpg->qobj;
 701         struct ft_cmd *cmd;
 702
 703         while (!kthread_should_stop()) {
 704                 schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
 705                 if (kthread_should_stop())
 706                         goto out;
 707
 708                 cmd = ft_dequeue_cmd(qobj);
 709                 if (cmd)
 710                         ft_exec_req(cmd);
 711         }
 712
 713 out:
 714         return 0;
 715 }