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 <asm/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 */ 31 static 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 63 void 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 69 static 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 85 void 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 92 int 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 */ 100 int 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 */ 177 int 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 */ 229 static 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 */ 265 static 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 */ 308 static 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 */ 320 static 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 */ 330 static 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 */ 375 void 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 } 409 410 void ft_aborted_task(struct se_cmd *se_cmd) 411 { 412 return; 413 } 414 415 static void ft_send_work(struct work_struct *work); 416 417 /* 418 * Handle incoming FCP command. 419 */ 420 static 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; 447 448 busy: 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 */ 460 void 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 */ 485 static 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; 559 560 err: 561 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); 562 } 563