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