a6bfb6deba94c611cdce8c2e52ce82c56e169972
[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_target(lport, ep->xid,
268                                                             cmd->sg,
269                                                             cmd->sg_cnt))
270                                 cmd->was_ddp_setup = 1;
271                 }
272         }
273         lport->tt.seq_send(lport, cmd->seq, fp);
274         return 0;
275 }
276
277 u32 ft_get_task_tag(struct se_cmd *se_cmd)
278 {
279         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
280
281         return fc_seq_exch(cmd->seq)->rxid;
282 }
283
284 int ft_get_cmd_state(struct se_cmd *se_cmd)
285 {
286         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
287
288         return cmd->state;
289 }
290
291 int ft_is_state_remove(struct se_cmd *se_cmd)
292 {
293         return 0;       /* XXX TBD */
294 }
295
296 /*
297  * FC sequence response handler for follow-on sequences (data) and aborts.
298  */
299 static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
300 {
301         struct ft_cmd *cmd = arg;
302         struct fc_frame_header *fh;
303
304         if (IS_ERR(fp)) {
305                 /* XXX need to find cmd if queued */
306                 cmd->se_cmd.t_state = TRANSPORT_REMOVE;
307                 cmd->seq = NULL;
308                 transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
309                 return;
310         }
311
312         fh = fc_frame_header_get(fp);
313
314         switch (fh->fh_r_ctl) {
315         case FC_RCTL_DD_SOL_DATA:       /* write data */
316                 ft_recv_write_data(cmd, fp);
317                 break;
318         case FC_RCTL_DD_UNSOL_CTL:      /* command */
319         case FC_RCTL_DD_SOL_CTL:        /* transfer ready */
320         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
321         default:
322                 pr_debug("%s: unhandled frame r_ctl %x\n",
323                        __func__, fh->fh_r_ctl);
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  */
376 static void ft_send_resp_code(struct ft_cmd *cmd,
377                               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 }
382
383
384 /*
385  * Send error or task management response.
386  * Always frees the cmd and associated state.
387  */
388 static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
389                                       enum fcp_resp_rsp_codes code)
390 {
391         ft_send_resp_code(cmd, code);
392         ft_free_cmd(cmd);
393 }
394
395 /*
396  * Handle Task Management Request.
397  */
398 static void ft_send_tm(struct ft_cmd *cmd)
399 {
400         struct se_tmr_req *tmr;
401         struct fcp_cmnd *fcp;
402         struct ft_sess *sess;
403         u8 tm_func;
404
405         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
406
407         switch (fcp->fc_tm_flags) {
408         case FCP_TMF_LUN_RESET:
409                 tm_func = TMR_LUN_RESET;
410                 break;
411         case FCP_TMF_TGT_RESET:
412                 tm_func = TMR_TARGET_WARM_RESET;
413                 break;
414         case FCP_TMF_CLR_TASK_SET:
415                 tm_func = TMR_CLEAR_TASK_SET;
416                 break;
417         case FCP_TMF_ABT_TASK_SET:
418                 tm_func = TMR_ABORT_TASK_SET;
419                 break;
420         case FCP_TMF_CLR_ACA:
421                 tm_func = TMR_CLEAR_ACA;
422                 break;
423         default:
424                 /*
425                  * FCP4r01 indicates having a combination of
426                  * tm_flags set is invalid.
427                  */
428                 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
429                 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
430                 return;
431         }
432
433         pr_debug("alloc tm cmd fn %d\n", tm_func);
434         tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
435         if (!tmr) {
436                 pr_debug("alloc failed\n");
437                 ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
438                 return;
439         }
440         cmd->se_cmd.se_tmr_req = tmr;
441
442         switch (fcp->fc_tm_flags) {
443         case FCP_TMF_LUN_RESET:
444                 cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
445                 if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
446                         /*
447                          * Make sure to clean up newly allocated TMR request
448                          * since "unable to  handle TMR request because failed
449                          * to get to LUN"
450                          */
451                         pr_debug("Failed to get LUN for TMR func %d, "
452                                   "se_cmd %p, unpacked_lun %d\n",
453                                   tm_func, &cmd->se_cmd, cmd->lun);
454                         ft_dump_cmd(cmd, __func__);
455                         sess = cmd->sess;
456                         transport_send_check_condition_and_sense(&cmd->se_cmd,
457                                 cmd->se_cmd.scsi_sense_reason, 0);
458                         transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
459                         ft_sess_put(sess);
460                         return;
461                 }
462                 break;
463         case FCP_TMF_TGT_RESET:
464         case FCP_TMF_CLR_TASK_SET:
465         case FCP_TMF_ABT_TASK_SET:
466         case FCP_TMF_CLR_ACA:
467                 break;
468         default:
469                 return;
470         }
471         transport_generic_handle_tmr(&cmd->se_cmd);
472 }
473
474 /*
475  * Send status from completed task management request.
476  */
477 int ft_queue_tm_resp(struct se_cmd *se_cmd)
478 {
479         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
480         struct se_tmr_req *tmr = se_cmd->se_tmr_req;
481         enum fcp_resp_rsp_codes code;
482
483         switch (tmr->response) {
484         case TMR_FUNCTION_COMPLETE:
485                 code = FCP_TMF_CMPL;
486                 break;
487         case TMR_LUN_DOES_NOT_EXIST:
488                 code = FCP_TMF_INVALID_LUN;
489                 break;
490         case TMR_FUNCTION_REJECTED:
491                 code = FCP_TMF_REJECTED;
492                 break;
493         case TMR_TASK_DOES_NOT_EXIST:
494         case TMR_TASK_STILL_ALLEGIANT:
495         case TMR_TASK_FAILOVER_NOT_SUPPORTED:
496         case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
497         case TMR_FUNCTION_AUTHORIZATION_FAILED:
498         default:
499                 code = FCP_TMF_FAILED;
500                 break;
501         }
502         pr_debug("tmr fn %d resp %d fcp code %d\n",
503                   tmr->function, tmr->response, code);
504         ft_send_resp_code(cmd, code);
505         return 0;
506 }
507
508 /*
509  * Handle incoming FCP command.
510  */
511 static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
512 {
513         struct ft_cmd *cmd;
514         struct fc_lport *lport = sess->tport->lport;
515
516         cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
517         if (!cmd)
518                 goto busy;
519         cmd->sess = sess;
520         cmd->seq = lport->tt.seq_assign(lport, fp);
521         if (!cmd->seq) {
522                 kfree(cmd);
523                 goto busy;
524         }
525         cmd->req_frame = fp;            /* hold frame during cmd */
526         ft_queue_cmd(sess, cmd);
527         return;
528
529 busy:
530         pr_debug("cmd or seq allocation failure - sending BUSY\n");
531         ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
532         fc_frame_free(fp);
533         ft_sess_put(sess);              /* undo get from lookup */
534 }
535
536
537 /*
538  * Handle incoming FCP frame.
539  * Caller has verified that the frame is type FCP.
540  */
541 void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
542 {
543         struct fc_frame_header *fh = fc_frame_header_get(fp);
544
545         switch (fh->fh_r_ctl) {
546         case FC_RCTL_DD_UNSOL_CMD:      /* command */
547                 ft_recv_cmd(sess, fp);
548                 break;
549         case FC_RCTL_DD_SOL_DATA:       /* write data */
550         case FC_RCTL_DD_UNSOL_CTL:
551         case FC_RCTL_DD_SOL_CTL:
552         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
553         case FC_RCTL_ELS4_REQ:          /* SRR, perhaps */
554         default:
555                 pr_debug("%s: unhandled frame r_ctl %x\n",
556                        __func__, fh->fh_r_ctl);
557                 fc_frame_free(fp);
558                 ft_sess_put(sess);      /* undo get from lookup */
559                 break;
560         }
561 }
562
563 /*
564  * Send new command to target.
565  */
566 static void ft_send_cmd(struct ft_cmd *cmd)
567 {
568         struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
569         struct se_cmd *se_cmd;
570         struct fcp_cmnd *fcp;
571         int data_dir;
572         u32 data_len;
573         int task_attr;
574         int ret;
575
576         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
577         if (!fcp)
578                 goto err;
579
580         if (fcp->fc_flags & FCP_CFL_LEN_MASK)
581                 goto err;               /* not handling longer CDBs yet */
582
583         if (fcp->fc_tm_flags) {
584                 task_attr = FCP_PTA_SIMPLE;
585                 data_dir = DMA_NONE;
586                 data_len = 0;
587         } else {
588                 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
589                 case 0:
590                         data_dir = DMA_NONE;
591                         break;
592                 case FCP_CFL_RDDATA:
593                         data_dir = DMA_FROM_DEVICE;
594                         break;
595                 case FCP_CFL_WRDATA:
596                         data_dir = DMA_TO_DEVICE;
597                         break;
598                 case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
599                         goto err;       /* TBD not supported by tcm_fc yet */
600                 }
601                 /*
602                  * Locate the SAM Task Attr from fc_pri_ta
603                  */
604                 switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
605                 case FCP_PTA_HEADQ:
606                         task_attr = MSG_HEAD_TAG;
607                         break;
608                 case FCP_PTA_ORDERED:
609                         task_attr = MSG_ORDERED_TAG;
610                         break;
611                 case FCP_PTA_ACA:
612                         task_attr = MSG_ACA_TAG;
613                         break;
614                 case FCP_PTA_SIMPLE: /* Fallthrough */
615                 default:
616                         task_attr = MSG_SIMPLE_TAG;
617                 }
618
619
620                 task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
621                 data_len = ntohl(fcp->fc_dl);
622                 cmd->cdb = fcp->fc_cdb;
623         }
624
625         se_cmd = &cmd->se_cmd;
626         /*
627          * Initialize struct se_cmd descriptor from target_core_mod
628          * infrastructure
629          */
630         transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
631                               data_len, data_dir, task_attr,
632                               &cmd->ft_sense_buffer[0]);
633         /*
634          * Check for FCP task management flags
635          */
636         if (fcp->fc_tm_flags) {
637                 ft_send_tm(cmd);
638                 return;
639         }
640
641         fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
642
643         cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
644         ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
645         if (ret < 0) {
646                 ft_dump_cmd(cmd, __func__);
647                 transport_send_check_condition_and_sense(&cmd->se_cmd,
648                         cmd->se_cmd.scsi_sense_reason, 0);
649                 return;
650         }
651
652         ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);
653
654         pr_debug("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
655         ft_dump_cmd(cmd, __func__);
656
657         if (ret == -ENOMEM) {
658                 transport_send_check_condition_and_sense(se_cmd,
659                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
660                 transport_generic_free_cmd(se_cmd, 0, 0);
661                 return;
662         }
663         if (ret == -EINVAL) {
664                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
665                         ft_queue_status(se_cmd);
666                 else
667                         transport_send_check_condition_and_sense(se_cmd,
668                                         se_cmd->scsi_sense_reason, 0);
669                 transport_generic_free_cmd(se_cmd, 0, 0);
670                 return;
671         }
672         transport_generic_handle_cdb(se_cmd);
673         return;
674
675 err:
676         ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
677 }
678
679 /*
680  * Handle request in the command thread.
681  */
682 static void ft_exec_req(struct ft_cmd *cmd)
683 {
684         pr_debug("cmd state %x\n", cmd->state);
685         switch (cmd->state) {
686         case FC_CMD_ST_NEW:
687                 ft_send_cmd(cmd);
688                 break;
689         default:
690                 break;
691         }
692 }
693
694 /*
695  * Processing thread.
696  * Currently one thread per tpg.
697  */
698 int ft_thread(void *arg)
699 {
700         struct ft_tpg *tpg = arg;
701         struct se_queue_obj *qobj = &tpg->qobj;
702         struct ft_cmd *cmd;
703
704         while (!kthread_should_stop()) {
705                 schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
706                 if (kthread_should_stop())
707                         goto out;
708
709                 cmd = ft_dequeue_cmd(qobj);
710                 if (cmd)
711                         ft_exec_req(cmd);
712         }
713
714 out:
715         return 0;
716 }