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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2010 Cisco Systems, Inc.
4 */
5
6/* XXX TBD some includes may be extraneous */
7
8#include <linux/module.h>
9#include <linux/moduleparam.h>
10#include <linux/utsname.h>
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <linux/kthread.h>
14#include <linux/types.h>
15#include <linux/string.h>
16#include <linux/configfs.h>
17#include <linux/ctype.h>
18#include <linux/hash.h>
19#include <linux/unaligned.h>
20#include <scsi/scsi_tcq.h>
21#include <scsi/libfc.h>
22
23#include <target/target_core_base.h>
24#include <target/target_core_fabric.h>
25
26#include "tcm_fc.h"
27
28/*
29 * Dump cmd state for debugging.
30 */
31static void _ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
32{
33 struct fc_exch *ep;
34 struct fc_seq *sp;
35 struct se_cmd *se_cmd;
36 struct scatterlist *sg;
37 int count;
38
39 se_cmd = &cmd->se_cmd;
40 pr_debug("%s: cmd %p sess %p seq %p se_cmd %p\n",
41 caller, cmd, cmd->sess, cmd->seq, se_cmd);
42
43 pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
44 caller, cmd, se_cmd->t_data_nents,
45 se_cmd->data_length, se_cmd->se_cmd_flags);
46
47 for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
48 pr_debug("%s: cmd %p sg %p page %p "
49 "len 0x%x off 0x%x\n",
50 caller, cmd, sg,
51 sg_page(sg), sg->length, sg->offset);
52
53 sp = cmd->seq;
54 if (sp) {
55 ep = fc_seq_exch(sp);
56 pr_debug("%s: cmd %p sid %x did %x "
57 "ox_id %x rx_id %x seq_id %x e_stat %x\n",
58 caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
59 sp->id, ep->esb_stat);
60 }
61}
62
63void ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
64{
65 if (unlikely(ft_debug_logging))
66 _ft_dump_cmd(cmd, caller);
67}
68
69static void ft_free_cmd(struct ft_cmd *cmd)
70{
71 struct fc_frame *fp;
72 struct ft_sess *sess;
73
74 if (!cmd)
75 return;
76 sess = cmd->sess;
77 fp = cmd->req_frame;
78 if (fr_seq(fp))
79 fc_seq_release(fr_seq(fp));
80 fc_frame_free(fp);
81 target_free_tag(sess->se_sess, &cmd->se_cmd);
82 ft_sess_put(sess); /* undo get from lookup at recv */
83}
84
85void ft_release_cmd(struct se_cmd *se_cmd)
86{
87 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
88
89 ft_free_cmd(cmd);
90}
91
92int ft_check_stop_free(struct se_cmd *se_cmd)
93{
94 return transport_generic_free_cmd(se_cmd, 0);
95}
96
97/*
98 * Send response.
99 */
100int ft_queue_status(struct se_cmd *se_cmd)
101{
102 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
103 struct fc_frame *fp;
104 struct fcp_resp_with_ext *fcp;
105 struct fc_lport *lport;
106 struct fc_exch *ep;
107 size_t len;
108 int rc;
109
110 if (cmd->aborted)
111 return 0;
112 ft_dump_cmd(cmd, __func__);
113 ep = fc_seq_exch(cmd->seq);
114 lport = ep->lp;
115 len = sizeof(*fcp) + se_cmd->scsi_sense_length;
116 fp = fc_frame_alloc(lport, len);
117 if (!fp) {
118 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
119 return -ENOMEM;
120 }
121
122 fcp = fc_frame_payload_get(fp, len);
123 memset(fcp, 0, len);
124 fcp->resp.fr_status = se_cmd->scsi_status;
125
126 len = se_cmd->scsi_sense_length;
127 if (len) {
128 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL;
129 fcp->ext.fr_sns_len = htonl(len);
130 memcpy((fcp + 1), se_cmd->sense_buffer, len);
131 }
132
133 /*
134 * Test underflow and overflow with one mask. Usually both are off.
135 * Bidirectional commands are not handled yet.
136 */
137 if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) {
138 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
139 fcp->resp.fr_flags |= FCP_RESID_OVER;
140 else
141 fcp->resp.fr_flags |= FCP_RESID_UNDER;
142 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
143 }
144
145 /*
146 * Send response.
147 */
148 cmd->seq = fc_seq_start_next(cmd->seq);
149 fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
150 FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0);
151
152 rc = fc_seq_send(lport, cmd->seq, fp);
153 if (rc) {
154 pr_info_ratelimited("%s: Failed to send response frame %p, "
155 "xid <0x%x>\n", __func__, fp, ep->xid);
156 /*
157 * Generate a TASK_SET_FULL status to notify the initiator
158 * to reduce it's queue_depth after the se_cmd response has
159 * been re-queued by target-core.
160 */
161 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
162 return -ENOMEM;
163 }
164 fc_exch_done(cmd->seq);
165 /*
166 * Drop the extra ACK_KREF reference taken by target_submit_cmd()
167 * ahead of ft_check_stop_free() -> transport_generic_free_cmd()
168 * final se_cmd->cmd_kref put.
169 */
170 target_put_sess_cmd(&cmd->se_cmd);
171 return 0;
172}
173
174/*
175 * Send TX_RDY (transfer ready).
176 */
177int ft_write_pending(struct se_cmd *se_cmd)
178{
179 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
180 struct fc_frame *fp;
181 struct fcp_txrdy *txrdy;
182 struct fc_lport *lport;
183 struct fc_exch *ep;
184 struct fc_frame_header *fh;
185 u32 f_ctl;
186
187 ft_dump_cmd(cmd, __func__);
188
189 if (cmd->aborted)
190 return 0;
191 ep = fc_seq_exch(cmd->seq);
192 lport = ep->lp;
193 fp = fc_frame_alloc(lport, sizeof(*txrdy));
194 if (!fp)
195 return -ENOMEM; /* Signal QUEUE_FULL */
196
197 txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
198 memset(txrdy, 0, sizeof(*txrdy));
199 txrdy->ft_burst_len = htonl(se_cmd->data_length);
200
201 cmd->seq = fc_seq_start_next(cmd->seq);
202 fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
203 FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
204
205 fh = fc_frame_header_get(fp);
206 f_ctl = ntoh24(fh->fh_f_ctl);
207
208 /* Only if it is 'Exchange Responder' */
209 if (f_ctl & FC_FC_EX_CTX) {
210 /* Target is 'exchange responder' and sending XFER_READY
211 * to 'exchange initiator (initiator)'
212 */
213 if ((ep->xid <= lport->lro_xid) &&
214 (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
215 if ((se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
216 lport->tt.ddp_target(lport, ep->xid,
217 se_cmd->t_data_sg,
218 se_cmd->t_data_nents))
219 cmd->was_ddp_setup = 1;
220 }
221 }
222 fc_seq_send(lport, cmd->seq, fp);
223 return 0;
224}
225
226/*
227 * FC sequence response handler for follow-on sequences (data) and aborts.
228 */
229static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
230{
231 struct ft_cmd *cmd = arg;
232 struct fc_frame_header *fh;
233
234 if (IS_ERR(fp)) {
235 /* XXX need to find cmd if queued */
236 cmd->seq = NULL;
237 cmd->aborted = true;
238 return;
239 }
240
241 fh = fc_frame_header_get(fp);
242
243 switch (fh->fh_r_ctl) {
244 case FC_RCTL_DD_SOL_DATA: /* write data */
245 ft_recv_write_data(cmd, fp);
246 break;
247 case FC_RCTL_DD_UNSOL_CTL: /* command */
248 case FC_RCTL_DD_SOL_CTL: /* transfer ready */
249 case FC_RCTL_DD_DATA_DESC: /* transfer ready */
250 default:
251 pr_debug("%s: unhandled frame r_ctl %x\n",
252 __func__, fh->fh_r_ctl);
253 ft_invl_hw_context(cmd);
254 fc_frame_free(fp);
255 transport_generic_free_cmd(&cmd->se_cmd, 0);
256 break;
257 }
258}
259
260/*
261 * Send a FCP response including SCSI status and optional FCP rsp_code.
262 * status is SAM_STAT_GOOD (zero) iff code is valid.
263 * This is used in error cases, such as allocation failures.
264 */
265static void ft_send_resp_status(struct fc_lport *lport,
266 const struct fc_frame *rx_fp,
267 u32 status, enum fcp_resp_rsp_codes code)
268{
269 struct fc_frame *fp;
270 struct fc_seq *sp;
271 const struct fc_frame_header *fh;
272 size_t len;
273 struct fcp_resp_with_ext *fcp;
274 struct fcp_resp_rsp_info *info;
275
276 fh = fc_frame_header_get(rx_fp);
277 pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
278 ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
279 len = sizeof(*fcp);
280 if (status == SAM_STAT_GOOD)
281 len += sizeof(*info);
282 fp = fc_frame_alloc(lport, len);
283 if (!fp)
284 return;
285 fcp = fc_frame_payload_get(fp, len);
286 memset(fcp, 0, len);
287 fcp->resp.fr_status = status;
288 if (status == SAM_STAT_GOOD) {
289 fcp->ext.fr_rsp_len = htonl(sizeof(*info));
290 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL;
291 info = (struct fcp_resp_rsp_info *)(fcp + 1);
292 info->rsp_code = code;
293 }
294
295 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
296 sp = fr_seq(fp);
297 if (sp) {
298 fc_seq_send(lport, sp, fp);
299 fc_exch_done(sp);
300 } else {
301 lport->tt.frame_send(lport, fp);
302 }
303}
304
305/*
306 * Send error or task management response.
307 */
308static void ft_send_resp_code(struct ft_cmd *cmd,
309 enum fcp_resp_rsp_codes code)
310{
311 ft_send_resp_status(cmd->sess->tport->lport,
312 cmd->req_frame, SAM_STAT_GOOD, code);
313}
314
315
316/*
317 * Send error or task management response.
318 * Always frees the cmd and associated state.
319 */
320static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
321 enum fcp_resp_rsp_codes code)
322{
323 ft_send_resp_code(cmd, code);
324 ft_free_cmd(cmd);
325}
326
327/*
328 * Handle Task Management Request.
329 */
330static void ft_send_tm(struct ft_cmd *cmd)
331{
332 struct fcp_cmnd *fcp;
333 int rc;
334 u8 tm_func;
335
336 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
337
338 switch (fcp->fc_tm_flags) {
339 case FCP_TMF_LUN_RESET:
340 tm_func = TMR_LUN_RESET;
341 break;
342 case FCP_TMF_TGT_RESET:
343 tm_func = TMR_TARGET_WARM_RESET;
344 break;
345 case FCP_TMF_CLR_TASK_SET:
346 tm_func = TMR_CLEAR_TASK_SET;
347 break;
348 case FCP_TMF_ABT_TASK_SET:
349 tm_func = TMR_ABORT_TASK_SET;
350 break;
351 case FCP_TMF_CLR_ACA:
352 tm_func = TMR_CLEAR_ACA;
353 break;
354 default:
355 /*
356 * FCP4r01 indicates having a combination of
357 * tm_flags set is invalid.
358 */
359 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
360 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
361 return;
362 }
363
364 /* FIXME: Add referenced task tag for ABORT_TASK */
365 rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess,
366 &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
367 cmd, tm_func, GFP_KERNEL, 0, TARGET_SCF_ACK_KREF);
368 if (rc < 0)
369 ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
370}
371
372/*
373 * Send status from completed task management request.
374 */
375void ft_queue_tm_resp(struct se_cmd *se_cmd)
376{
377 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
378 struct se_tmr_req *tmr = se_cmd->se_tmr_req;
379 enum fcp_resp_rsp_codes code;
380
381 if (cmd->aborted)
382 return;
383 switch (tmr->response) {
384 case TMR_FUNCTION_COMPLETE:
385 code = FCP_TMF_CMPL;
386 break;
387 case TMR_LUN_DOES_NOT_EXIST:
388 code = FCP_TMF_INVALID_LUN;
389 break;
390 case TMR_FUNCTION_REJECTED:
391 code = FCP_TMF_REJECTED;
392 break;
393 case TMR_TASK_DOES_NOT_EXIST:
394 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
395 default:
396 code = FCP_TMF_FAILED;
397 break;
398 }
399 pr_debug("tmr fn %d resp %d fcp code %d\n",
400 tmr->function, tmr->response, code);
401 ft_send_resp_code(cmd, code);
402 /*
403 * Drop the extra ACK_KREF reference taken by target_submit_tmr()
404 * ahead of ft_check_stop_free() -> transport_generic_free_cmd()
405 * final se_cmd->cmd_kref put.
406 */
407 target_put_sess_cmd(&cmd->se_cmd);
408}
409
410void ft_aborted_task(struct se_cmd *se_cmd)
411{
412 return;
413}
414
415static void ft_send_work(struct work_struct *work);
416
417/*
418 * Handle incoming FCP command.
419 */
420static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
421{
422 struct ft_cmd *cmd;
423 struct fc_lport *lport = sess->tport->lport;
424 struct se_session *se_sess = sess->se_sess;
425 int tag, cpu;
426
427 tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
428 if (tag < 0)
429 goto busy;
430
431 cmd = &((struct ft_cmd *)se_sess->sess_cmd_map)[tag];
432 memset(cmd, 0, sizeof(struct ft_cmd));
433
434 cmd->se_cmd.map_tag = tag;
435 cmd->se_cmd.map_cpu = cpu;
436 cmd->sess = sess;
437 cmd->seq = fc_seq_assign(lport, fp);
438 if (!cmd->seq) {
439 target_free_tag(se_sess, &cmd->se_cmd);
440 goto busy;
441 }
442 cmd->req_frame = fp; /* hold frame during cmd */
443
444 INIT_WORK(&cmd->work, ft_send_work);
445 queue_work(sess->tport->tpg->workqueue, &cmd->work);
446 return;
447
448busy:
449 pr_debug("cmd or seq allocation failure - sending BUSY\n");
450 ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
451 fc_frame_free(fp);
452 ft_sess_put(sess); /* undo get from lookup */
453}
454
455
456/*
457 * Handle incoming FCP frame.
458 * Caller has verified that the frame is type FCP.
459 */
460void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
461{
462 struct fc_frame_header *fh = fc_frame_header_get(fp);
463
464 switch (fh->fh_r_ctl) {
465 case FC_RCTL_DD_UNSOL_CMD: /* command */
466 ft_recv_cmd(sess, fp);
467 break;
468 case FC_RCTL_DD_SOL_DATA: /* write data */
469 case FC_RCTL_DD_UNSOL_CTL:
470 case FC_RCTL_DD_SOL_CTL:
471 case FC_RCTL_DD_DATA_DESC: /* transfer ready */
472 case FC_RCTL_ELS4_REQ: /* SRR, perhaps */
473 default:
474 pr_debug("%s: unhandled frame r_ctl %x\n",
475 __func__, fh->fh_r_ctl);
476 fc_frame_free(fp);
477 ft_sess_put(sess); /* undo get from lookup */
478 break;
479 }
480}
481
482/*
483 * Send new command to target.
484 */
485static void ft_send_work(struct work_struct *work)
486{
487 struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);
488 struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
489 struct fcp_cmnd *fcp;
490 int data_dir = 0;
491 int task_attr;
492
493 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
494 if (!fcp)
495 goto err;
496
497 if (fcp->fc_flags & FCP_CFL_LEN_MASK)
498 goto err; /* not handling longer CDBs yet */
499
500 /*
501 * Check for FCP task management flags
502 */
503 if (fcp->fc_tm_flags) {
504 ft_send_tm(cmd);
505 return;
506 }
507
508 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
509 case 0:
510 data_dir = DMA_NONE;
511 break;
512 case FCP_CFL_RDDATA:
513 data_dir = DMA_FROM_DEVICE;
514 break;
515 case FCP_CFL_WRDATA:
516 data_dir = DMA_TO_DEVICE;
517 break;
518 case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
519 goto err; /* TBD not supported by tcm_fc yet */
520 }
521 /*
522 * Locate the SAM Task Attr from fc_pri_ta
523 */
524 switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
525 case FCP_PTA_HEADQ:
526 task_attr = TCM_HEAD_TAG;
527 break;
528 case FCP_PTA_ORDERED:
529 task_attr = TCM_ORDERED_TAG;
530 break;
531 case FCP_PTA_ACA:
532 task_attr = TCM_ACA_TAG;
533 break;
534 case FCP_PTA_SIMPLE:
535 default:
536 task_attr = TCM_SIMPLE_TAG;
537 }
538
539 fc_seq_set_resp(cmd->seq, ft_recv_seq, cmd);
540 cmd->se_cmd.tag = fc_seq_exch(cmd->seq)->rxid;
541
542 /*
543 * Use a single se_cmd->cmd_kref as we expect to release se_cmd
544 * directly from ft_check_stop_free callback in response path.
545 */
546 if (target_init_cmd(&cmd->se_cmd, cmd->sess->se_sess,
547 &cmd->ft_sense_buffer[0],
548 scsilun_to_int(&fcp->fc_lun), ntohl(fcp->fc_dl),
549 task_attr, data_dir, TARGET_SCF_ACK_KREF))
550 goto err;
551
552 if (target_submit_prep(&cmd->se_cmd, fcp->fc_cdb, NULL, 0, NULL, 0,
553 NULL, 0, GFP_KERNEL))
554 return;
555
556 target_submit(&cmd->se_cmd);
557 pr_debug("r_ctl %x target_submit_cmd %p\n", fh->fh_r_ctl, cmd);
558 return;
559
560err:
561 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
562}
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/utsname.h>
23#include <linux/init.h>
24#include <linux/slab.h>
25#include <linux/kthread.h>
26#include <linux/types.h>
27#include <linux/string.h>
28#include <linux/configfs.h>
29#include <linux/ctype.h>
30#include <linux/hash.h>
31#include <linux/percpu_ida.h>
32#include <asm/unaligned.h>
33#include <scsi/scsi_tcq.h>
34#include <scsi/libfc.h>
35#include <scsi/fc_encode.h>
36
37#include <target/target_core_base.h>
38#include <target/target_core_fabric.h>
39
40#include "tcm_fc.h"
41
42/*
43 * Dump cmd state for debugging.
44 */
45static void _ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
46{
47 struct fc_exch *ep;
48 struct fc_seq *sp;
49 struct se_cmd *se_cmd;
50 struct scatterlist *sg;
51 int count;
52
53 se_cmd = &cmd->se_cmd;
54 pr_debug("%s: cmd %p sess %p seq %p se_cmd %p\n",
55 caller, cmd, cmd->sess, cmd->seq, se_cmd);
56
57 pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
58 caller, cmd, se_cmd->t_data_nents,
59 se_cmd->data_length, se_cmd->se_cmd_flags);
60
61 for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
62 pr_debug("%s: cmd %p sg %p page %p "
63 "len 0x%x off 0x%x\n",
64 caller, cmd, sg,
65 sg_page(sg), sg->length, sg->offset);
66
67 sp = cmd->seq;
68 if (sp) {
69 ep = fc_seq_exch(sp);
70 pr_debug("%s: cmd %p sid %x did %x "
71 "ox_id %x rx_id %x seq_id %x e_stat %x\n",
72 caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
73 sp->id, ep->esb_stat);
74 }
75}
76
77void ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
78{
79 if (unlikely(ft_debug_logging))
80 _ft_dump_cmd(cmd, caller);
81}
82
83static void ft_free_cmd(struct ft_cmd *cmd)
84{
85 struct fc_frame *fp;
86 struct ft_sess *sess;
87
88 if (!cmd)
89 return;
90 sess = cmd->sess;
91 fp = cmd->req_frame;
92 if (fr_seq(fp))
93 fc_seq_release(fr_seq(fp));
94 fc_frame_free(fp);
95 percpu_ida_free(&sess->se_sess->sess_tag_pool, cmd->se_cmd.map_tag);
96 ft_sess_put(sess); /* undo get from lookup at recv */
97}
98
99void ft_release_cmd(struct se_cmd *se_cmd)
100{
101 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
102
103 ft_free_cmd(cmd);
104}
105
106int ft_check_stop_free(struct se_cmd *se_cmd)
107{
108 return transport_generic_free_cmd(se_cmd, 0);
109}
110
111/*
112 * Send response.
113 */
114int ft_queue_status(struct se_cmd *se_cmd)
115{
116 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
117 struct fc_frame *fp;
118 struct fcp_resp_with_ext *fcp;
119 struct fc_lport *lport;
120 struct fc_exch *ep;
121 size_t len;
122 int rc;
123
124 if (cmd->aborted)
125 return 0;
126 ft_dump_cmd(cmd, __func__);
127 ep = fc_seq_exch(cmd->seq);
128 lport = ep->lp;
129 len = sizeof(*fcp) + se_cmd->scsi_sense_length;
130 fp = fc_frame_alloc(lport, len);
131 if (!fp) {
132 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
133 return -ENOMEM;
134 }
135
136 fcp = fc_frame_payload_get(fp, len);
137 memset(fcp, 0, len);
138 fcp->resp.fr_status = se_cmd->scsi_status;
139
140 len = se_cmd->scsi_sense_length;
141 if (len) {
142 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL;
143 fcp->ext.fr_sns_len = htonl(len);
144 memcpy((fcp + 1), se_cmd->sense_buffer, len);
145 }
146
147 /*
148 * Test underflow and overflow with one mask. Usually both are off.
149 * Bidirectional commands are not handled yet.
150 */
151 if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) {
152 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
153 fcp->resp.fr_flags |= FCP_RESID_OVER;
154 else
155 fcp->resp.fr_flags |= FCP_RESID_UNDER;
156 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
157 }
158
159 /*
160 * Send response.
161 */
162 cmd->seq = fc_seq_start_next(cmd->seq);
163 fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
164 FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0);
165
166 rc = fc_seq_send(lport, cmd->seq, fp);
167 if (rc) {
168 pr_info_ratelimited("%s: Failed to send response frame %p, "
169 "xid <0x%x>\n", __func__, fp, ep->xid);
170 /*
171 * Generate a TASK_SET_FULL status to notify the initiator
172 * to reduce it's queue_depth after the se_cmd response has
173 * been re-queued by target-core.
174 */
175 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
176 return -ENOMEM;
177 }
178 fc_exch_done(cmd->seq);
179 /*
180 * Drop the extra ACK_KREF reference taken by target_submit_cmd()
181 * ahead of ft_check_stop_free() -> transport_generic_free_cmd()
182 * final se_cmd->cmd_kref put.
183 */
184 target_put_sess_cmd(&cmd->se_cmd);
185 return 0;
186}
187
188int ft_write_pending_status(struct se_cmd *se_cmd)
189{
190 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
191
192 return cmd->write_data_len != se_cmd->data_length;
193}
194
195/*
196 * Send TX_RDY (transfer ready).
197 */
198int ft_write_pending(struct se_cmd *se_cmd)
199{
200 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
201 struct fc_frame *fp;
202 struct fcp_txrdy *txrdy;
203 struct fc_lport *lport;
204 struct fc_exch *ep;
205 struct fc_frame_header *fh;
206 u32 f_ctl;
207
208 ft_dump_cmd(cmd, __func__);
209
210 if (cmd->aborted)
211 return 0;
212 ep = fc_seq_exch(cmd->seq);
213 lport = ep->lp;
214 fp = fc_frame_alloc(lport, sizeof(*txrdy));
215 if (!fp)
216 return -ENOMEM; /* Signal QUEUE_FULL */
217
218 txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
219 memset(txrdy, 0, sizeof(*txrdy));
220 txrdy->ft_burst_len = htonl(se_cmd->data_length);
221
222 cmd->seq = fc_seq_start_next(cmd->seq);
223 fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
224 FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
225
226 fh = fc_frame_header_get(fp);
227 f_ctl = ntoh24(fh->fh_f_ctl);
228
229 /* Only if it is 'Exchange Responder' */
230 if (f_ctl & FC_FC_EX_CTX) {
231 /* Target is 'exchange responder' and sending XFER_READY
232 * to 'exchange initiator (initiator)'
233 */
234 if ((ep->xid <= lport->lro_xid) &&
235 (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
236 if ((se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
237 lport->tt.ddp_target(lport, ep->xid,
238 se_cmd->t_data_sg,
239 se_cmd->t_data_nents))
240 cmd->was_ddp_setup = 1;
241 }
242 }
243 fc_seq_send(lport, cmd->seq, fp);
244 return 0;
245}
246
247int ft_get_cmd_state(struct se_cmd *se_cmd)
248{
249 return 0;
250}
251
252/*
253 * FC sequence response handler for follow-on sequences (data) and aborts.
254 */
255static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
256{
257 struct ft_cmd *cmd = arg;
258 struct fc_frame_header *fh;
259
260 if (IS_ERR(fp)) {
261 /* XXX need to find cmd if queued */
262 cmd->seq = NULL;
263 cmd->aborted = true;
264 return;
265 }
266
267 fh = fc_frame_header_get(fp);
268
269 switch (fh->fh_r_ctl) {
270 case FC_RCTL_DD_SOL_DATA: /* write data */
271 ft_recv_write_data(cmd, fp);
272 break;
273 case FC_RCTL_DD_UNSOL_CTL: /* command */
274 case FC_RCTL_DD_SOL_CTL: /* transfer ready */
275 case FC_RCTL_DD_DATA_DESC: /* transfer ready */
276 default:
277 pr_debug("%s: unhandled frame r_ctl %x\n",
278 __func__, fh->fh_r_ctl);
279 ft_invl_hw_context(cmd);
280 fc_frame_free(fp);
281 transport_generic_free_cmd(&cmd->se_cmd, 0);
282 break;
283 }
284}
285
286/*
287 * Send a FCP response including SCSI status and optional FCP rsp_code.
288 * status is SAM_STAT_GOOD (zero) iff code is valid.
289 * This is used in error cases, such as allocation failures.
290 */
291static void ft_send_resp_status(struct fc_lport *lport,
292 const struct fc_frame *rx_fp,
293 u32 status, enum fcp_resp_rsp_codes code)
294{
295 struct fc_frame *fp;
296 struct fc_seq *sp;
297 const struct fc_frame_header *fh;
298 size_t len;
299 struct fcp_resp_with_ext *fcp;
300 struct fcp_resp_rsp_info *info;
301
302 fh = fc_frame_header_get(rx_fp);
303 pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
304 ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
305 len = sizeof(*fcp);
306 if (status == SAM_STAT_GOOD)
307 len += sizeof(*info);
308 fp = fc_frame_alloc(lport, len);
309 if (!fp)
310 return;
311 fcp = fc_frame_payload_get(fp, len);
312 memset(fcp, 0, len);
313 fcp->resp.fr_status = status;
314 if (status == SAM_STAT_GOOD) {
315 fcp->ext.fr_rsp_len = htonl(sizeof(*info));
316 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL;
317 info = (struct fcp_resp_rsp_info *)(fcp + 1);
318 info->rsp_code = code;
319 }
320
321 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
322 sp = fr_seq(fp);
323 if (sp) {
324 fc_seq_send(lport, sp, fp);
325 fc_exch_done(sp);
326 } else {
327 lport->tt.frame_send(lport, fp);
328 }
329}
330
331/*
332 * Send error or task management response.
333 */
334static void ft_send_resp_code(struct ft_cmd *cmd,
335 enum fcp_resp_rsp_codes code)
336{
337 ft_send_resp_status(cmd->sess->tport->lport,
338 cmd->req_frame, SAM_STAT_GOOD, code);
339}
340
341
342/*
343 * Send error or task management response.
344 * Always frees the cmd and associated state.
345 */
346static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
347 enum fcp_resp_rsp_codes code)
348{
349 ft_send_resp_code(cmd, code);
350 ft_free_cmd(cmd);
351}
352
353/*
354 * Handle Task Management Request.
355 */
356static void ft_send_tm(struct ft_cmd *cmd)
357{
358 struct fcp_cmnd *fcp;
359 int rc;
360 u8 tm_func;
361
362 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
363
364 switch (fcp->fc_tm_flags) {
365 case FCP_TMF_LUN_RESET:
366 tm_func = TMR_LUN_RESET;
367 break;
368 case FCP_TMF_TGT_RESET:
369 tm_func = TMR_TARGET_WARM_RESET;
370 break;
371 case FCP_TMF_CLR_TASK_SET:
372 tm_func = TMR_CLEAR_TASK_SET;
373 break;
374 case FCP_TMF_ABT_TASK_SET:
375 tm_func = TMR_ABORT_TASK_SET;
376 break;
377 case FCP_TMF_CLR_ACA:
378 tm_func = TMR_CLEAR_ACA;
379 break;
380 default:
381 /*
382 * FCP4r01 indicates having a combination of
383 * tm_flags set is invalid.
384 */
385 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
386 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
387 return;
388 }
389
390 /* FIXME: Add referenced task tag for ABORT_TASK */
391 rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess,
392 &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
393 cmd, tm_func, GFP_KERNEL, 0, TARGET_SCF_ACK_KREF);
394 if (rc < 0)
395 ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
396}
397
398/*
399 * Send status from completed task management request.
400 */
401void ft_queue_tm_resp(struct se_cmd *se_cmd)
402{
403 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
404 struct se_tmr_req *tmr = se_cmd->se_tmr_req;
405 enum fcp_resp_rsp_codes code;
406
407 if (cmd->aborted)
408 return;
409 switch (tmr->response) {
410 case TMR_FUNCTION_COMPLETE:
411 code = FCP_TMF_CMPL;
412 break;
413 case TMR_LUN_DOES_NOT_EXIST:
414 code = FCP_TMF_INVALID_LUN;
415 break;
416 case TMR_FUNCTION_REJECTED:
417 code = FCP_TMF_REJECTED;
418 break;
419 case TMR_TASK_DOES_NOT_EXIST:
420 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
421 default:
422 code = FCP_TMF_FAILED;
423 break;
424 }
425 pr_debug("tmr fn %d resp %d fcp code %d\n",
426 tmr->function, tmr->response, code);
427 ft_send_resp_code(cmd, code);
428 /*
429 * Drop the extra ACK_KREF reference taken by target_submit_tmr()
430 * ahead of ft_check_stop_free() -> transport_generic_free_cmd()
431 * final se_cmd->cmd_kref put.
432 */
433 target_put_sess_cmd(&cmd->se_cmd);
434}
435
436void ft_aborted_task(struct se_cmd *se_cmd)
437{
438 return;
439}
440
441static void ft_send_work(struct work_struct *work);
442
443/*
444 * Handle incoming FCP command.
445 */
446static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
447{
448 struct ft_cmd *cmd;
449 struct fc_lport *lport = sess->tport->lport;
450 struct se_session *se_sess = sess->se_sess;
451 int tag;
452
453 tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
454 if (tag < 0)
455 goto busy;
456
457 cmd = &((struct ft_cmd *)se_sess->sess_cmd_map)[tag];
458 memset(cmd, 0, sizeof(struct ft_cmd));
459
460 cmd->se_cmd.map_tag = tag;
461 cmd->sess = sess;
462 cmd->seq = fc_seq_assign(lport, fp);
463 if (!cmd->seq) {
464 percpu_ida_free(&se_sess->sess_tag_pool, tag);
465 goto busy;
466 }
467 cmd->req_frame = fp; /* hold frame during cmd */
468
469 INIT_WORK(&cmd->work, ft_send_work);
470 queue_work(sess->tport->tpg->workqueue, &cmd->work);
471 return;
472
473busy:
474 pr_debug("cmd or seq allocation failure - sending BUSY\n");
475 ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
476 fc_frame_free(fp);
477 ft_sess_put(sess); /* undo get from lookup */
478}
479
480
481/*
482 * Handle incoming FCP frame.
483 * Caller has verified that the frame is type FCP.
484 */
485void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
486{
487 struct fc_frame_header *fh = fc_frame_header_get(fp);
488
489 switch (fh->fh_r_ctl) {
490 case FC_RCTL_DD_UNSOL_CMD: /* command */
491 ft_recv_cmd(sess, fp);
492 break;
493 case FC_RCTL_DD_SOL_DATA: /* write data */
494 case FC_RCTL_DD_UNSOL_CTL:
495 case FC_RCTL_DD_SOL_CTL:
496 case FC_RCTL_DD_DATA_DESC: /* transfer ready */
497 case FC_RCTL_ELS4_REQ: /* SRR, perhaps */
498 default:
499 pr_debug("%s: unhandled frame r_ctl %x\n",
500 __func__, fh->fh_r_ctl);
501 fc_frame_free(fp);
502 ft_sess_put(sess); /* undo get from lookup */
503 break;
504 }
505}
506
507/*
508 * Send new command to target.
509 */
510static void ft_send_work(struct work_struct *work)
511{
512 struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);
513 struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
514 struct fcp_cmnd *fcp;
515 int data_dir = 0;
516 int task_attr;
517
518 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
519 if (!fcp)
520 goto err;
521
522 if (fcp->fc_flags & FCP_CFL_LEN_MASK)
523 goto err; /* not handling longer CDBs yet */
524
525 /*
526 * Check for FCP task management flags
527 */
528 if (fcp->fc_tm_flags) {
529 ft_send_tm(cmd);
530 return;
531 }
532
533 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
534 case 0:
535 data_dir = DMA_NONE;
536 break;
537 case FCP_CFL_RDDATA:
538 data_dir = DMA_FROM_DEVICE;
539 break;
540 case FCP_CFL_WRDATA:
541 data_dir = DMA_TO_DEVICE;
542 break;
543 case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
544 goto err; /* TBD not supported by tcm_fc yet */
545 }
546 /*
547 * Locate the SAM Task Attr from fc_pri_ta
548 */
549 switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
550 case FCP_PTA_HEADQ:
551 task_attr = TCM_HEAD_TAG;
552 break;
553 case FCP_PTA_ORDERED:
554 task_attr = TCM_ORDERED_TAG;
555 break;
556 case FCP_PTA_ACA:
557 task_attr = TCM_ACA_TAG;
558 break;
559 case FCP_PTA_SIMPLE: /* Fallthrough */
560 default:
561 task_attr = TCM_SIMPLE_TAG;
562 }
563
564 fc_seq_set_resp(cmd->seq, ft_recv_seq, cmd);
565 cmd->se_cmd.tag = fc_seq_exch(cmd->seq)->rxid;
566 /*
567 * Use a single se_cmd->cmd_kref as we expect to release se_cmd
568 * directly from ft_check_stop_free callback in response path.
569 */
570 if (target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb,
571 &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
572 ntohl(fcp->fc_dl), task_attr, data_dir,
573 TARGET_SCF_ACK_KREF | TARGET_SCF_USE_CPUID))
574 goto err;
575
576 pr_debug("r_ctl %x target_submit_cmd %p\n", fh->fh_r_ctl, cmd);
577 return;
578
579err:
580 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
581}