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