tcm_fc: Handle DDP/SW fc_frame_payload_get failures in ft_recv_write_data
[linux-2.6.git] / 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         se_cmd = &cmd->se_cmd;
66         pr_debug("%s: cmd %p state %d sess %p seq %p se_cmd %p\n",
67                 caller, cmd, cmd->state, cmd->sess, cmd->seq, se_cmd);
68         pr_debug("%s: cmd %p cdb %p\n",
69                 caller, cmd, cmd->cdb);
70         pr_debug("%s: cmd %p lun %d\n", caller, cmd, cmd->lun);
71
72         pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
73                 caller, cmd, se_cmd->t_data_nents,
74                se_cmd->data_length, se_cmd->se_cmd_flags);
75
76         for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
77                 pr_debug("%s: cmd %p sg %p page %p "
78                         "len 0x%x off 0x%x\n",
79                         caller, cmd, sg,
80                         sg_page(sg), sg->length, sg->offset);
81
82         sp = cmd->seq;
83         if (sp) {
84                 ep = fc_seq_exch(sp);
85                 pr_debug("%s: cmd %p sid %x did %x "
86                         "ox_id %x rx_id %x seq_id %x e_stat %x\n",
87                         caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
88                         sp->id, ep->esb_stat);
89         }
90         print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE,
91                 16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0);
92 }
93
94 static void ft_queue_cmd(struct ft_sess *sess, struct ft_cmd *cmd)
95 {
96         struct ft_tpg *tpg = sess->tport->tpg;
97         struct se_queue_obj *qobj = &tpg->qobj;
98         unsigned long flags;
99
100         qobj = &sess->tport->tpg->qobj;
101         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
102         list_add_tail(&cmd->se_req.qr_list, &qobj->qobj_list);
103         atomic_inc(&qobj->queue_cnt);
104         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
105
106         wake_up_process(tpg->thread);
107 }
108
109 static struct ft_cmd *ft_dequeue_cmd(struct se_queue_obj *qobj)
110 {
111         unsigned long flags;
112         struct se_queue_req *qr;
113
114         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
115         if (list_empty(&qobj->qobj_list)) {
116                 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
117                 return NULL;
118         }
119         qr = list_first_entry(&qobj->qobj_list, struct se_queue_req, qr_list);
120         list_del(&qr->qr_list);
121         atomic_dec(&qobj->queue_cnt);
122         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
123         return container_of(qr, struct ft_cmd, se_req);
124 }
125
126 static void ft_free_cmd(struct ft_cmd *cmd)
127 {
128         struct fc_frame *fp;
129         struct fc_lport *lport;
130
131         if (!cmd)
132                 return;
133         fp = cmd->req_frame;
134         lport = fr_dev(fp);
135         if (fr_seq(fp))
136                 lport->tt.seq_release(fr_seq(fp));
137         fc_frame_free(fp);
138         ft_sess_put(cmd->sess); /* undo get from lookup at recv */
139         kfree(cmd);
140 }
141
142 void ft_release_cmd(struct se_cmd *se_cmd)
143 {
144         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
145
146         ft_free_cmd(cmd);
147 }
148
149 void ft_check_stop_free(struct se_cmd *se_cmd)
150 {
151         transport_generic_free_cmd(se_cmd, 0, 0);
152 }
153
154 /*
155  * Send response.
156  */
157 int ft_queue_status(struct se_cmd *se_cmd)
158 {
159         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
160         struct fc_frame *fp;
161         struct fcp_resp_with_ext *fcp;
162         struct fc_lport *lport;
163         struct fc_exch *ep;
164         size_t len;
165
166         ft_dump_cmd(cmd, __func__);
167         ep = fc_seq_exch(cmd->seq);
168         lport = ep->lp;
169         len = sizeof(*fcp) + se_cmd->scsi_sense_length;
170         fp = fc_frame_alloc(lport, len);
171         if (!fp) {
172                 /* XXX shouldn't just drop it - requeue and retry? */
173                 return 0;
174         }
175         fcp = fc_frame_payload_get(fp, len);
176         memset(fcp, 0, len);
177         fcp->resp.fr_status = se_cmd->scsi_status;
178
179         len = se_cmd->scsi_sense_length;
180         if (len) {
181                 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL;
182                 fcp->ext.fr_sns_len = htonl(len);
183                 memcpy((fcp + 1), se_cmd->sense_buffer, len);
184         }
185
186         /*
187          * Test underflow and overflow with one mask.  Usually both are off.
188          * Bidirectional commands are not handled yet.
189          */
190         if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) {
191                 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
192                         fcp->resp.fr_flags |= FCP_RESID_OVER;
193                 else
194                         fcp->resp.fr_flags |= FCP_RESID_UNDER;
195                 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
196         }
197
198         /*
199          * Send response.
200          */
201         cmd->seq = lport->tt.seq_start_next(cmd->seq);
202         fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
203                        FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0);
204
205         lport->tt.seq_send(lport, cmd->seq, fp);
206         lport->tt.exch_done(cmd->seq);
207         return 0;
208 }
209
210 int ft_write_pending_status(struct se_cmd *se_cmd)
211 {
212         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
213
214         return cmd->write_data_len != se_cmd->data_length;
215 }
216
217 /*
218  * Send TX_RDY (transfer ready).
219  */
220 int ft_write_pending(struct se_cmd *se_cmd)
221 {
222         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
223         struct fc_frame *fp;
224         struct fcp_txrdy *txrdy;
225         struct fc_lport *lport;
226         struct fc_exch *ep;
227         struct fc_frame_header *fh;
228         u32 f_ctl;
229
230         ft_dump_cmd(cmd, __func__);
231
232         ep = fc_seq_exch(cmd->seq);
233         lport = ep->lp;
234         fp = fc_frame_alloc(lport, sizeof(*txrdy));
235         if (!fp)
236                 return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
237
238         txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
239         memset(txrdy, 0, sizeof(*txrdy));
240         txrdy->ft_burst_len = htonl(se_cmd->data_length);
241
242         cmd->seq = lport->tt.seq_start_next(cmd->seq);
243         fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
244                        FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
245
246         fh = fc_frame_header_get(fp);
247         f_ctl = ntoh24(fh->fh_f_ctl);
248
249         /* Only if it is 'Exchange Responder' */
250         if (f_ctl & FC_FC_EX_CTX) {
251                 /* Target is 'exchange responder' and sending XFER_READY
252                  * to 'exchange initiator (initiator)'
253                  */
254                 if ((ep->xid <= lport->lro_xid) &&
255                     (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
256                         if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
257                                 /*
258                                  * cmd may have been broken up into multiple
259                                  * tasks. Link their sgs together so we can
260                                  * operate on them all at once.
261                                  */
262                                 transport_do_task_sg_chain(se_cmd);
263                                 cmd->sg = se_cmd->t_tasks_sg_chained;
264                                 cmd->sg_cnt =
265                                         se_cmd->t_tasks_sg_chained_no;
266                         }
267                         if (cmd->sg && lport->tt.ddp_setup(lport, ep->xid,
268                                                     cmd->sg, cmd->sg_cnt))
269                                 cmd->was_ddp_setup = 1;
270                 }
271         }
272         lport->tt.seq_send(lport, cmd->seq, fp);
273         return 0;
274 }
275
276 u32 ft_get_task_tag(struct se_cmd *se_cmd)
277 {
278         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
279
280         return fc_seq_exch(cmd->seq)->rxid;
281 }
282
283 int ft_get_cmd_state(struct se_cmd *se_cmd)
284 {
285         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
286
287         return cmd->state;
288 }
289
290 int ft_is_state_remove(struct se_cmd *se_cmd)
291 {
292         return 0;       /* XXX TBD */
293 }
294
295 /*
296  * FC sequence response handler for follow-on sequences (data) and aborts.
297  */
298 static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
299 {
300         struct ft_cmd *cmd = arg;
301         struct fc_frame_header *fh;
302
303         if (IS_ERR(fp)) {
304                 /* XXX need to find cmd if queued */
305                 cmd->se_cmd.t_state = TRANSPORT_REMOVE;
306                 cmd->seq = NULL;
307                 transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
308                 return;
309         }
310
311         fh = fc_frame_header_get(fp);
312
313         switch (fh->fh_r_ctl) {
314         case FC_RCTL_DD_SOL_DATA:       /* write data */
315                 ft_recv_write_data(cmd, fp);
316                 break;
317         case FC_RCTL_DD_UNSOL_CTL:      /* command */
318         case FC_RCTL_DD_SOL_CTL:        /* transfer ready */
319         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
320         default:
321                 pr_debug("%s: unhandled frame r_ctl %x\n",
322                        __func__, fh->fh_r_ctl);
323                 ft_invl_hw_context(cmd);
324                 fc_frame_free(fp);
325                 transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
326                 break;
327         }
328 }
329
330 /*
331  * Send a FCP response including SCSI status and optional FCP rsp_code.
332  * status is SAM_STAT_GOOD (zero) iff code is valid.
333  * This is used in error cases, such as allocation failures.
334  */
335 static void ft_send_resp_status(struct fc_lport *lport,
336                                 const struct fc_frame *rx_fp,
337                                 u32 status, enum fcp_resp_rsp_codes code)
338 {
339         struct fc_frame *fp;
340         struct fc_seq *sp;
341         const struct fc_frame_header *fh;
342         size_t len;
343         struct fcp_resp_with_ext *fcp;
344         struct fcp_resp_rsp_info *info;
345
346         fh = fc_frame_header_get(rx_fp);
347         pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
348                   ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
349         len = sizeof(*fcp);
350         if (status == SAM_STAT_GOOD)
351                 len += sizeof(*info);
352         fp = fc_frame_alloc(lport, len);
353         if (!fp)
354                 return;
355         fcp = fc_frame_payload_get(fp, len);
356         memset(fcp, 0, len);
357         fcp->resp.fr_status = status;
358         if (status == SAM_STAT_GOOD) {
359                 fcp->ext.fr_rsp_len = htonl(sizeof(*info));
360                 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL;
361                 info = (struct fcp_resp_rsp_info *)(fcp + 1);
362                 info->rsp_code = code;
363         }
364
365         fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
366         sp = fr_seq(fp);
367         if (sp)
368                 lport->tt.seq_send(lport, sp, fp);
369         else
370                 lport->tt.frame_send(lport, fp);
371 }
372
373 /*
374  * Send error or task management response.
375  * Always frees the cmd and associated state.
376  */
377 static void ft_send_resp_code(struct ft_cmd *cmd, enum fcp_resp_rsp_codes code)
378 {
379         ft_send_resp_status(cmd->sess->tport->lport,
380                             cmd->req_frame, SAM_STAT_GOOD, code);
381         ft_free_cmd(cmd);
382 }
383
384 /*
385  * Handle Task Management Request.
386  */
387 static void ft_send_tm(struct ft_cmd *cmd)
388 {
389         struct se_tmr_req *tmr;
390         struct fcp_cmnd *fcp;
391         struct ft_sess *sess;
392         u8 tm_func;
393
394         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
395
396         switch (fcp->fc_tm_flags) {
397         case FCP_TMF_LUN_RESET:
398                 tm_func = TMR_LUN_RESET;
399                 break;
400         case FCP_TMF_TGT_RESET:
401                 tm_func = TMR_TARGET_WARM_RESET;
402                 break;
403         case FCP_TMF_CLR_TASK_SET:
404                 tm_func = TMR_CLEAR_TASK_SET;
405                 break;
406         case FCP_TMF_ABT_TASK_SET:
407                 tm_func = TMR_ABORT_TASK_SET;
408                 break;
409         case FCP_TMF_CLR_ACA:
410                 tm_func = TMR_CLEAR_ACA;
411                 break;
412         default:
413                 /*
414                  * FCP4r01 indicates having a combination of
415                  * tm_flags set is invalid.
416                  */
417                 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
418                 ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
419                 return;
420         }
421
422         pr_debug("alloc tm cmd fn %d\n", tm_func);
423         tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
424         if (!tmr) {
425                 pr_debug("alloc failed\n");
426                 ft_send_resp_code(cmd, FCP_TMF_FAILED);
427                 return;
428         }
429         cmd->se_cmd.se_tmr_req = tmr;
430
431         switch (fcp->fc_tm_flags) {
432         case FCP_TMF_LUN_RESET:
433                 cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
434                 if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
435                         /*
436                          * Make sure to clean up newly allocated TMR request
437                          * since "unable to  handle TMR request because failed
438                          * to get to LUN"
439                          */
440                         pr_debug("Failed to get LUN for TMR func %d, "
441                                   "se_cmd %p, unpacked_lun %d\n",
442                                   tm_func, &cmd->se_cmd, cmd->lun);
443                         ft_dump_cmd(cmd, __func__);
444                         sess = cmd->sess;
445                         transport_send_check_condition_and_sense(&cmd->se_cmd,
446                                 cmd->se_cmd.scsi_sense_reason, 0);
447                         transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
448                         ft_sess_put(sess);
449                         return;
450                 }
451                 break;
452         case FCP_TMF_TGT_RESET:
453         case FCP_TMF_CLR_TASK_SET:
454         case FCP_TMF_ABT_TASK_SET:
455         case FCP_TMF_CLR_ACA:
456                 break;
457         default:
458                 return;
459         }
460         transport_generic_handle_tmr(&cmd->se_cmd);
461 }
462
463 /*
464  * Send status from completed task management request.
465  */
466 int ft_queue_tm_resp(struct se_cmd *se_cmd)
467 {
468         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
469         struct se_tmr_req *tmr = se_cmd->se_tmr_req;
470         enum fcp_resp_rsp_codes code;
471
472         switch (tmr->response) {
473         case TMR_FUNCTION_COMPLETE:
474                 code = FCP_TMF_CMPL;
475                 break;
476         case TMR_LUN_DOES_NOT_EXIST:
477                 code = FCP_TMF_INVALID_LUN;
478                 break;
479         case TMR_FUNCTION_REJECTED:
480                 code = FCP_TMF_REJECTED;
481                 break;
482         case TMR_TASK_DOES_NOT_EXIST:
483         case TMR_TASK_STILL_ALLEGIANT:
484         case TMR_TASK_FAILOVER_NOT_SUPPORTED:
485         case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
486         case TMR_FUNCTION_AUTHORIZATION_FAILED:
487         default:
488                 code = FCP_TMF_FAILED;
489                 break;
490         }
491         pr_debug("tmr fn %d resp %d fcp code %d\n",
492                   tmr->function, tmr->response, code);
493         ft_send_resp_code(cmd, code);
494         return 0;
495 }
496
497 /*
498  * Handle incoming FCP command.
499  */
500 static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
501 {
502         struct ft_cmd *cmd;
503         struct fc_lport *lport = sess->tport->lport;
504
505         cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
506         if (!cmd)
507                 goto busy;
508         cmd->sess = sess;
509         cmd->seq = lport->tt.seq_assign(lport, fp);
510         if (!cmd->seq) {
511                 kfree(cmd);
512                 goto busy;
513         }
514         cmd->req_frame = fp;            /* hold frame during cmd */
515         ft_queue_cmd(sess, cmd);
516         return;
517
518 busy:
519         pr_debug("cmd or seq allocation failure - sending BUSY\n");
520         ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
521         fc_frame_free(fp);
522         ft_sess_put(sess);              /* undo get from lookup */
523 }
524
525
526 /*
527  * Handle incoming FCP frame.
528  * Caller has verified that the frame is type FCP.
529  */
530 void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
531 {
532         struct fc_frame_header *fh = fc_frame_header_get(fp);
533
534         switch (fh->fh_r_ctl) {
535         case FC_RCTL_DD_UNSOL_CMD:      /* command */
536                 ft_recv_cmd(sess, fp);
537                 break;
538         case FC_RCTL_DD_SOL_DATA:       /* write data */
539         case FC_RCTL_DD_UNSOL_CTL:
540         case FC_RCTL_DD_SOL_CTL:
541         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
542         case FC_RCTL_ELS4_REQ:          /* SRR, perhaps */
543         default:
544                 pr_debug("%s: unhandled frame r_ctl %x\n",
545                        __func__, fh->fh_r_ctl);
546                 fc_frame_free(fp);
547                 ft_sess_put(sess);      /* undo get from lookup */
548                 break;
549         }
550 }
551
552 /*
553  * Send new command to target.
554  */
555 static void ft_send_cmd(struct ft_cmd *cmd)
556 {
557         struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
558         struct se_cmd *se_cmd;
559         struct fcp_cmnd *fcp;
560         int data_dir;
561         u32 data_len;
562         int task_attr;
563         int ret;
564
565         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
566         if (!fcp)
567                 goto err;
568
569         if (fcp->fc_flags & FCP_CFL_LEN_MASK)
570                 goto err;               /* not handling longer CDBs yet */
571
572         if (fcp->fc_tm_flags) {
573                 task_attr = FCP_PTA_SIMPLE;
574                 data_dir = DMA_NONE;
575                 data_len = 0;
576         } else {
577                 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
578                 case 0:
579                         data_dir = DMA_NONE;
580                         break;
581                 case FCP_CFL_RDDATA:
582                         data_dir = DMA_FROM_DEVICE;
583                         break;
584                 case FCP_CFL_WRDATA:
585                         data_dir = DMA_TO_DEVICE;
586                         break;
587                 case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
588                         goto err;       /* TBD not supported by tcm_fc yet */
589                 }
590                 /*
591                  * Locate the SAM Task Attr from fc_pri_ta
592                  */
593                 switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
594                 case FCP_PTA_HEADQ:
595                         task_attr = MSG_HEAD_TAG;
596                         break;
597                 case FCP_PTA_ORDERED:
598                         task_attr = MSG_ORDERED_TAG;
599                         break;
600                 case FCP_PTA_ACA:
601                         task_attr = MSG_ACA_TAG;
602                         break;
603                 case FCP_PTA_SIMPLE: /* Fallthrough */
604                 default:
605                         task_attr = MSG_SIMPLE_TAG;
606                 }
607
608
609                 task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
610                 data_len = ntohl(fcp->fc_dl);
611                 cmd->cdb = fcp->fc_cdb;
612         }
613
614         se_cmd = &cmd->se_cmd;
615         /*
616          * Initialize struct se_cmd descriptor from target_core_mod
617          * infrastructure
618          */
619         transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
620                               data_len, data_dir, task_attr,
621                               &cmd->ft_sense_buffer[0]);
622         /*
623          * Check for FCP task management flags
624          */
625         if (fcp->fc_tm_flags) {
626                 ft_send_tm(cmd);
627                 return;
628         }
629
630         fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
631
632         cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
633         ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
634         if (ret < 0) {
635                 ft_dump_cmd(cmd, __func__);
636                 transport_send_check_condition_and_sense(&cmd->se_cmd,
637                         cmd->se_cmd.scsi_sense_reason, 0);
638                 return;
639         }
640
641         ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);
642
643         pr_debug("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
644         ft_dump_cmd(cmd, __func__);
645
646         if (ret == -ENOMEM) {
647                 transport_send_check_condition_and_sense(se_cmd,
648                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
649                 transport_generic_free_cmd(se_cmd, 0, 0);
650                 return;
651         }
652         if (ret == -EINVAL) {
653                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
654                         ft_queue_status(se_cmd);
655                 else
656                         transport_send_check_condition_and_sense(se_cmd,
657                                         se_cmd->scsi_sense_reason, 0);
658                 transport_generic_free_cmd(se_cmd, 0, 0);
659                 return;
660         }
661         transport_generic_handle_cdb(se_cmd);
662         return;
663
664 err:
665         ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
666 }
667
668 /*
669  * Handle request in the command thread.
670  */
671 static void ft_exec_req(struct ft_cmd *cmd)
672 {
673         pr_debug("cmd state %x\n", cmd->state);
674         switch (cmd->state) {
675         case FC_CMD_ST_NEW:
676                 ft_send_cmd(cmd);
677                 break;
678         default:
679                 break;
680         }
681 }
682
683 /*
684  * Processing thread.
685  * Currently one thread per tpg.
686  */
687 int ft_thread(void *arg)
688 {
689         struct ft_tpg *tpg = arg;
690         struct se_queue_obj *qobj = &tpg->qobj;
691         struct ft_cmd *cmd;
692
693         while (!kthread_should_stop()) {
694                 schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
695                 if (kthread_should_stop())
696                         goto out;
697
698                 cmd = ft_dequeue_cmd(qobj);
699                 if (cmd)
700                         ft_exec_req(cmd);
701         }
702
703 out:
704         return 0;
705 }