910306ce48de72ceacc2c4cff437a8fc885da2bc
[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 se_mem *mem;
63
64         if (!(ft_debug_logging & FT_DEBUG_IO))
65                 return;
66
67         se_cmd = &cmd->se_cmd;
68         printk(KERN_INFO "%s: cmd %p state %d sess %p seq %p se_cmd %p\n",
69                 caller, cmd, cmd->state, cmd->sess, cmd->seq, se_cmd);
70         printk(KERN_INFO "%s: cmd %p cdb %p\n",
71                 caller, cmd, cmd->cdb);
72         printk(KERN_INFO "%s: cmd %p lun %d\n", caller, cmd, cmd->lun);
73
74         printk(KERN_INFO "%s: cmd %p se_num %u buf %p len %u se_cmd_flags <0x%x>\n",
75                caller, cmd, se_cmd->t_tasks_se_num,
76                se_cmd->t_task_buf, se_cmd->data_length, se_cmd->se_cmd_flags);
77
78         list_for_each_entry(mem, &se_cmd->t_mem_list, se_list)
79                 printk(KERN_INFO "%s: cmd %p mem %p page %p "
80                        "len 0x%x off 0x%x\n",
81                        caller, cmd, mem,
82                        mem->se_page, mem->se_len, mem->se_off);
83         sp = cmd->seq;
84         if (sp) {
85                 ep = fc_seq_exch(sp);
86                 printk(KERN_INFO "%s: cmd %p sid %x did %x "
87                         "ox_id %x rx_id %x seq_id %x e_stat %x\n",
88                         caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
89                         sp->id, ep->esb_stat);
90         }
91         print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE,
92                 16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0);
93 }
94
95 static void ft_queue_cmd(struct ft_sess *sess, struct ft_cmd *cmd)
96 {
97         struct se_queue_obj *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         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
104         atomic_inc(&qobj->queue_cnt);
105         wake_up_interruptible(&qobj->thread_wq);
106 }
107
108 static struct ft_cmd *ft_dequeue_cmd(struct se_queue_obj *qobj)
109 {
110         unsigned long flags;
111         struct se_queue_req *qr;
112
113         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
114         if (list_empty(&qobj->qobj_list)) {
115                 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
116                 return NULL;
117         }
118         qr = list_first_entry(&qobj->qobj_list, struct se_queue_req, qr_list);
119         list_del(&qr->qr_list);
120         atomic_dec(&qobj->queue_cnt);
121         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
122         return container_of(qr, struct ft_cmd, se_req);
123 }
124
125 static void ft_free_cmd(struct ft_cmd *cmd)
126 {
127         struct fc_frame *fp;
128         struct fc_lport *lport;
129
130         if (!cmd)
131                 return;
132         fp = cmd->req_frame;
133         lport = fr_dev(fp);
134         if (fr_seq(fp))
135                 lport->tt.seq_release(fr_seq(fp));
136         fc_frame_free(fp);
137         ft_sess_put(cmd->sess); /* undo get from lookup at recv */
138         kfree(cmd);
139 }
140
141 void ft_release_cmd(struct se_cmd *se_cmd)
142 {
143         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
144
145         ft_free_cmd(cmd);
146 }
147
148 void ft_check_stop_free(struct se_cmd *se_cmd)
149 {
150         transport_generic_free_cmd(se_cmd, 0, 1, 0);
151 }
152
153 /*
154  * Send response.
155  */
156 int ft_queue_status(struct se_cmd *se_cmd)
157 {
158         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
159         struct fc_frame *fp;
160         struct fcp_resp_with_ext *fcp;
161         struct fc_lport *lport;
162         struct fc_exch *ep;
163         size_t len;
164
165         ft_dump_cmd(cmd, __func__);
166         ep = fc_seq_exch(cmd->seq);
167         lport = ep->lp;
168         len = sizeof(*fcp) + se_cmd->scsi_sense_length;
169         fp = fc_frame_alloc(lport, len);
170         if (!fp) {
171                 /* XXX shouldn't just drop it - requeue and retry? */
172                 return 0;
173         }
174         fcp = fc_frame_payload_get(fp, len);
175         memset(fcp, 0, len);
176         fcp->resp.fr_status = se_cmd->scsi_status;
177
178         len = se_cmd->scsi_sense_length;
179         if (len) {
180                 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL;
181                 fcp->ext.fr_sns_len = htonl(len);
182                 memcpy((fcp + 1), se_cmd->sense_buffer, len);
183         }
184
185         /*
186          * Test underflow and overflow with one mask.  Usually both are off.
187          * Bidirectional commands are not handled yet.
188          */
189         if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) {
190                 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
191                         fcp->resp.fr_flags |= FCP_RESID_OVER;
192                 else
193                         fcp->resp.fr_flags |= FCP_RESID_UNDER;
194                 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
195         }
196
197         /*
198          * Send response.
199          */
200         cmd->seq = lport->tt.seq_start_next(cmd->seq);
201         fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
202                        FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0);
203
204         lport->tt.seq_send(lport, cmd->seq, fp);
205         lport->tt.exch_done(cmd->seq);
206         return 0;
207 }
208
209 int ft_write_pending_status(struct se_cmd *se_cmd)
210 {
211         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
212
213         return cmd->write_data_len != se_cmd->data_length;
214 }
215
216 /*
217  * Send TX_RDY (transfer ready).
218  */
219 int ft_write_pending(struct se_cmd *se_cmd)
220 {
221         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
222         struct fc_frame *fp;
223         struct fcp_txrdy *txrdy;
224         struct fc_lport *lport;
225         struct fc_exch *ep;
226         struct fc_frame_header *fh;
227         u32 f_ctl;
228
229         ft_dump_cmd(cmd, __func__);
230
231         ep = fc_seq_exch(cmd->seq);
232         lport = ep->lp;
233         fp = fc_frame_alloc(lport, sizeof(*txrdy));
234         if (!fp)
235                 return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
236
237         txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
238         memset(txrdy, 0, sizeof(*txrdy));
239         txrdy->ft_burst_len = htonl(se_cmd->data_length);
240
241         cmd->seq = lport->tt.seq_start_next(cmd->seq);
242         fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
243                        FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
244
245         fh = fc_frame_header_get(fp);
246         f_ctl = ntoh24(fh->fh_f_ctl);
247
248         /* Only if it is 'Exchange Responder' */
249         if (f_ctl & FC_FC_EX_CTX) {
250                 /* Target is 'exchange responder' and sending XFER_READY
251                  * to 'exchange initiator (initiator)'
252                  */
253                 if ((ep->xid <= lport->lro_xid) &&
254                     (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
255                         if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
256                                 /*
257                                  * Map se_mem list to scatterlist, so that
258                                  * DDP can be setup. DDP setup function require
259                                  * scatterlist. se_mem_list is internal to
260                                  * TCM/LIO target
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 void ft_new_cmd_failure(struct se_cmd *se_cmd)
296 {
297         /* XXX TBD */
298         printk(KERN_INFO "%s: se_cmd %p\n", __func__, se_cmd);
299 }
300
301 /*
302  * FC sequence response handler for follow-on sequences (data) and aborts.
303  */
304 static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
305 {
306         struct ft_cmd *cmd = arg;
307         struct fc_frame_header *fh;
308
309         if (IS_ERR(fp)) {
310                 /* XXX need to find cmd if queued */
311                 cmd->se_cmd.t_state = TRANSPORT_REMOVE;
312                 cmd->seq = NULL;
313                 transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 0);
314                 return;
315         }
316
317         fh = fc_frame_header_get(fp);
318
319         switch (fh->fh_r_ctl) {
320         case FC_RCTL_DD_SOL_DATA:       /* write data */
321                 ft_recv_write_data(cmd, fp);
322                 break;
323         case FC_RCTL_DD_UNSOL_CTL:      /* command */
324         case FC_RCTL_DD_SOL_CTL:        /* transfer ready */
325         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
326         default:
327                 printk(KERN_INFO "%s: unhandled frame r_ctl %x\n",
328                        __func__, fh->fh_r_ctl);
329                 fc_frame_free(fp);
330                 transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 0);
331                 break;
332         }
333 }
334
335 /*
336  * Send a FCP response including SCSI status and optional FCP rsp_code.
337  * status is SAM_STAT_GOOD (zero) iff code is valid.
338  * This is used in error cases, such as allocation failures.
339  */
340 static void ft_send_resp_status(struct fc_lport *lport,
341                                 const struct fc_frame *rx_fp,
342                                 u32 status, enum fcp_resp_rsp_codes code)
343 {
344         struct fc_frame *fp;
345         struct fc_seq *sp;
346         const struct fc_frame_header *fh;
347         size_t len;
348         struct fcp_resp_with_ext *fcp;
349         struct fcp_resp_rsp_info *info;
350
351         fh = fc_frame_header_get(rx_fp);
352         FT_IO_DBG("FCP error response: did %x oxid %x status %x code %x\n",
353                   ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
354         len = sizeof(*fcp);
355         if (status == SAM_STAT_GOOD)
356                 len += sizeof(*info);
357         fp = fc_frame_alloc(lport, len);
358         if (!fp)
359                 return;
360         fcp = fc_frame_payload_get(fp, len);
361         memset(fcp, 0, len);
362         fcp->resp.fr_status = status;
363         if (status == SAM_STAT_GOOD) {
364                 fcp->ext.fr_rsp_len = htonl(sizeof(*info));
365                 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL;
366                 info = (struct fcp_resp_rsp_info *)(fcp + 1);
367                 info->rsp_code = code;
368         }
369
370         fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
371         sp = fr_seq(fp);
372         if (sp)
373                 lport->tt.seq_send(lport, sp, fp);
374         else
375                 lport->tt.frame_send(lport, fp);
376 }
377
378 /*
379  * Send error or task management response.
380  * Always frees the cmd and associated state.
381  */
382 static void ft_send_resp_code(struct ft_cmd *cmd, enum fcp_resp_rsp_codes code)
383 {
384         ft_send_resp_status(cmd->sess->tport->lport,
385                             cmd->req_frame, SAM_STAT_GOOD, code);
386         ft_free_cmd(cmd);
387 }
388
389 /*
390  * Handle Task Management Request.
391  */
392 static void ft_send_tm(struct ft_cmd *cmd)
393 {
394         struct se_tmr_req *tmr;
395         struct fcp_cmnd *fcp;
396         struct ft_sess *sess;
397         u8 tm_func;
398
399         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
400
401         switch (fcp->fc_tm_flags) {
402         case FCP_TMF_LUN_RESET:
403                 tm_func = TMR_LUN_RESET;
404                 break;
405         case FCP_TMF_TGT_RESET:
406                 tm_func = TMR_TARGET_WARM_RESET;
407                 break;
408         case FCP_TMF_CLR_TASK_SET:
409                 tm_func = TMR_CLEAR_TASK_SET;
410                 break;
411         case FCP_TMF_ABT_TASK_SET:
412                 tm_func = TMR_ABORT_TASK_SET;
413                 break;
414         case FCP_TMF_CLR_ACA:
415                 tm_func = TMR_CLEAR_ACA;
416                 break;
417         default:
418                 /*
419                  * FCP4r01 indicates having a combination of
420                  * tm_flags set is invalid.
421                  */
422                 FT_TM_DBG("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
423                 ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
424                 return;
425         }
426
427         FT_TM_DBG("alloc tm cmd fn %d\n", tm_func);
428         tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
429         if (!tmr) {
430                 FT_TM_DBG("alloc failed\n");
431                 ft_send_resp_code(cmd, FCP_TMF_FAILED);
432                 return;
433         }
434         cmd->se_cmd.se_tmr_req = tmr;
435
436         switch (fcp->fc_tm_flags) {
437         case FCP_TMF_LUN_RESET:
438                 cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
439                 if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
440                         /*
441                          * Make sure to clean up newly allocated TMR request
442                          * since "unable to  handle TMR request because failed
443                          * to get to LUN"
444                          */
445                         FT_TM_DBG("Failed to get LUN for TMR func %d, "
446                                   "se_cmd %p, unpacked_lun %d\n",
447                                   tm_func, &cmd->se_cmd, cmd->lun);
448                         ft_dump_cmd(cmd, __func__);
449                         sess = cmd->sess;
450                         transport_send_check_condition_and_sense(&cmd->se_cmd,
451                                 cmd->se_cmd.scsi_sense_reason, 0);
452                         transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 0);
453                         ft_sess_put(sess);
454                         return;
455                 }
456                 break;
457         case FCP_TMF_TGT_RESET:
458         case FCP_TMF_CLR_TASK_SET:
459         case FCP_TMF_ABT_TASK_SET:
460         case FCP_TMF_CLR_ACA:
461                 break;
462         default:
463                 return;
464         }
465         transport_generic_handle_tmr(&cmd->se_cmd);
466 }
467
468 /*
469  * Send status from completed task management request.
470  */
471 int ft_queue_tm_resp(struct se_cmd *se_cmd)
472 {
473         struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
474         struct se_tmr_req *tmr = se_cmd->se_tmr_req;
475         enum fcp_resp_rsp_codes code;
476
477         switch (tmr->response) {
478         case TMR_FUNCTION_COMPLETE:
479                 code = FCP_TMF_CMPL;
480                 break;
481         case TMR_LUN_DOES_NOT_EXIST:
482                 code = FCP_TMF_INVALID_LUN;
483                 break;
484         case TMR_FUNCTION_REJECTED:
485                 code = FCP_TMF_REJECTED;
486                 break;
487         case TMR_TASK_DOES_NOT_EXIST:
488         case TMR_TASK_STILL_ALLEGIANT:
489         case TMR_TASK_FAILOVER_NOT_SUPPORTED:
490         case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
491         case TMR_FUNCTION_AUTHORIZATION_FAILED:
492         default:
493                 code = FCP_TMF_FAILED;
494                 break;
495         }
496         FT_TM_DBG("tmr fn %d resp %d fcp code %d\n",
497                   tmr->function, tmr->response, code);
498         ft_send_resp_code(cmd, code);
499         return 0;
500 }
501
502 /*
503  * Handle incoming FCP command.
504  */
505 static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
506 {
507         struct ft_cmd *cmd;
508         struct fc_lport *lport = sess->tport->lport;
509
510         cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
511         if (!cmd)
512                 goto busy;
513         cmd->sess = sess;
514         cmd->seq = lport->tt.seq_assign(lport, fp);
515         if (!cmd->seq) {
516                 kfree(cmd);
517                 goto busy;
518         }
519         cmd->req_frame = fp;            /* hold frame during cmd */
520         ft_queue_cmd(sess, cmd);
521         return;
522
523 busy:
524         FT_IO_DBG("cmd or seq allocation failure - sending BUSY\n");
525         ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
526         fc_frame_free(fp);
527         ft_sess_put(sess);              /* undo get from lookup */
528 }
529
530
531 /*
532  * Handle incoming FCP frame.
533  * Caller has verified that the frame is type FCP.
534  */
535 void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
536 {
537         struct fc_frame_header *fh = fc_frame_header_get(fp);
538
539         switch (fh->fh_r_ctl) {
540         case FC_RCTL_DD_UNSOL_CMD:      /* command */
541                 ft_recv_cmd(sess, fp);
542                 break;
543         case FC_RCTL_DD_SOL_DATA:       /* write data */
544         case FC_RCTL_DD_UNSOL_CTL:
545         case FC_RCTL_DD_SOL_CTL:
546         case FC_RCTL_DD_DATA_DESC:      /* transfer ready */
547         case FC_RCTL_ELS4_REQ:          /* SRR, perhaps */
548         default:
549                 printk(KERN_INFO "%s: unhandled frame r_ctl %x\n",
550                        __func__, fh->fh_r_ctl);
551                 fc_frame_free(fp);
552                 ft_sess_put(sess);      /* undo get from lookup */
553                 break;
554         }
555 }
556
557 /*
558  * Send new command to target.
559  */
560 static void ft_send_cmd(struct ft_cmd *cmd)
561 {
562         struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
563         struct se_cmd *se_cmd;
564         struct fcp_cmnd *fcp;
565         int data_dir;
566         u32 data_len;
567         int task_attr;
568         int ret;
569
570         fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
571         if (!fcp)
572                 goto err;
573
574         if (fcp->fc_flags & FCP_CFL_LEN_MASK)
575                 goto err;               /* not handling longer CDBs yet */
576
577         if (fcp->fc_tm_flags) {
578                 task_attr = FCP_PTA_SIMPLE;
579                 data_dir = DMA_NONE;
580                 data_len = 0;
581         } else {
582                 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
583                 case 0:
584                         data_dir = DMA_NONE;
585                         break;
586                 case FCP_CFL_RDDATA:
587                         data_dir = DMA_FROM_DEVICE;
588                         break;
589                 case FCP_CFL_WRDATA:
590                         data_dir = DMA_TO_DEVICE;
591                         break;
592                 case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
593                         goto err;       /* TBD not supported by tcm_fc yet */
594                 }
595                 /*
596                  * Locate the SAM Task Attr from fc_pri_ta
597                  */
598                 switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
599                 case FCP_PTA_HEADQ:
600                         task_attr = MSG_HEAD_TAG;
601                         break;
602                 case FCP_PTA_ORDERED:
603                         task_attr = MSG_ORDERED_TAG;
604                         break;
605                 case FCP_PTA_ACA:
606                         task_attr = MSG_ACA_TAG;
607                         break;
608                 case FCP_PTA_SIMPLE: /* Fallthrough */
609                 default:
610                         task_attr = MSG_SIMPLE_TAG;
611                 }
612
613
614                 task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
615                 data_len = ntohl(fcp->fc_dl);
616                 cmd->cdb = fcp->fc_cdb;
617         }
618
619         se_cmd = &cmd->se_cmd;
620         /*
621          * Initialize struct se_cmd descriptor from target_core_mod
622          * infrastructure
623          */
624         transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
625                               data_len, data_dir, task_attr,
626                               &cmd->ft_sense_buffer[0]);
627         /*
628          * Check for FCP task management flags
629          */
630         if (fcp->fc_tm_flags) {
631                 ft_send_tm(cmd);
632                 return;
633         }
634
635         fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
636
637         cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
638         ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
639         if (ret < 0) {
640                 ft_dump_cmd(cmd, __func__);
641                 transport_send_check_condition_and_sense(&cmd->se_cmd,
642                         cmd->se_cmd.scsi_sense_reason, 0);
643                 return;
644         }
645
646         ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);
647
648         FT_IO_DBG("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
649         ft_dump_cmd(cmd, __func__);
650
651         if (ret == -ENOMEM) {
652                 transport_send_check_condition_and_sense(se_cmd,
653                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
654                 transport_generic_free_cmd(se_cmd, 0, 1, 0);
655                 return;
656         }
657         if (ret == -EINVAL) {
658                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
659                         ft_queue_status(se_cmd);
660                 else
661                         transport_send_check_condition_and_sense(se_cmd,
662                                         se_cmd->scsi_sense_reason, 0);
663                 transport_generic_free_cmd(se_cmd, 0, 1, 0);
664                 return;
665         }
666         transport_generic_handle_cdb(se_cmd);
667         return;
668
669 err:
670         ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
671 }
672
673 /*
674  * Handle request in the command thread.
675  */
676 static void ft_exec_req(struct ft_cmd *cmd)
677 {
678         FT_IO_DBG("cmd state %x\n", cmd->state);
679         switch (cmd->state) {
680         case FC_CMD_ST_NEW:
681                 ft_send_cmd(cmd);
682                 break;
683         default:
684                 break;
685         }
686 }
687
688 /*
689  * Processing thread.
690  * Currently one thread per tpg.
691  */
692 int ft_thread(void *arg)
693 {
694         struct ft_tpg *tpg = arg;
695         struct se_queue_obj *qobj = &tpg->qobj;
696         struct ft_cmd *cmd;
697         int ret;
698
699         set_user_nice(current, -20);
700
701         while (!kthread_should_stop()) {
702                 ret = wait_event_interruptible(qobj->thread_wq,
703                         atomic_read(&qobj->queue_cnt) || kthread_should_stop());
704                 if (ret < 0 || kthread_should_stop())
705                         goto out;
706                 cmd = ft_dequeue_cmd(qobj);
707                 if (cmd)
708                         ft_exec_req(cmd);
709         }
710
711 out:
712         return 0;
713 }