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 pr_debug("%s: cmd %p lun %d\n", caller, cmd, cmd->lun); 65 66 pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n", 67 caller, cmd, se_cmd->t_data_nents, 68 se_cmd->data_length, se_cmd->se_cmd_flags); 69 70 for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count) 71 pr_debug("%s: cmd %p sg %p page %p " 72 "len 0x%x off 0x%x\n", 73 caller, cmd, sg, 74 sg_page(sg), sg->length, sg->offset); 75 76 sp = cmd->seq; 77 if (sp) { 78 ep = fc_seq_exch(sp); 79 pr_debug("%s: cmd %p sid %x did %x " 80 "ox_id %x rx_id %x seq_id %x e_stat %x\n", 81 caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid, 82 sp->id, ep->esb_stat); 83 } 84 print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE, 85 16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0); 86 } 87 88 static void ft_free_cmd(struct ft_cmd *cmd) 89 { 90 struct fc_frame *fp; 91 struct fc_lport *lport; 92 93 if (!cmd) 94 return; 95 fp = cmd->req_frame; 96 lport = fr_dev(fp); 97 if (fr_seq(fp)) 98 lport->tt.seq_release(fr_seq(fp)); 99 fc_frame_free(fp); 100 ft_sess_put(cmd->sess); /* undo get from lookup at recv */ 101 kfree(cmd); 102 } 103 104 void ft_release_cmd(struct se_cmd *se_cmd) 105 { 106 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 107 108 ft_free_cmd(cmd); 109 } 110 111 int ft_check_stop_free(struct se_cmd *se_cmd) 112 { 113 transport_generic_free_cmd(se_cmd, 0); 114 return 1; 115 } 116 117 /* 118 * Send response. 119 */ 120 int ft_queue_status(struct se_cmd *se_cmd) 121 { 122 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 123 struct fc_frame *fp; 124 struct fcp_resp_with_ext *fcp; 125 struct fc_lport *lport; 126 struct fc_exch *ep; 127 size_t len; 128 129 ft_dump_cmd(cmd, __func__); 130 ep = fc_seq_exch(cmd->seq); 131 lport = ep->lp; 132 len = sizeof(*fcp) + se_cmd->scsi_sense_length; 133 fp = fc_frame_alloc(lport, len); 134 if (!fp) { 135 /* XXX shouldn't just drop it - requeue and retry? */ 136 return 0; 137 } 138 fcp = fc_frame_payload_get(fp, len); 139 memset(fcp, 0, len); 140 fcp->resp.fr_status = se_cmd->scsi_status; 141 142 len = se_cmd->scsi_sense_length; 143 if (len) { 144 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL; 145 fcp->ext.fr_sns_len = htonl(len); 146 memcpy((fcp + 1), se_cmd->sense_buffer, len); 147 } 148 149 /* 150 * Test underflow and overflow with one mask. Usually both are off. 151 * Bidirectional commands are not handled yet. 152 */ 153 if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) { 154 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) 155 fcp->resp.fr_flags |= FCP_RESID_OVER; 156 else 157 fcp->resp.fr_flags |= FCP_RESID_UNDER; 158 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count); 159 } 160 161 /* 162 * Send response. 163 */ 164 cmd->seq = lport->tt.seq_start_next(cmd->seq); 165 fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP, 166 FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0); 167 168 lport->tt.seq_send(lport, cmd->seq, fp); 169 lport->tt.exch_done(cmd->seq); 170 return 0; 171 } 172 173 int ft_write_pending_status(struct se_cmd *se_cmd) 174 { 175 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 176 177 return cmd->write_data_len != se_cmd->data_length; 178 } 179 180 /* 181 * Send TX_RDY (transfer ready). 182 */ 183 int ft_write_pending(struct se_cmd *se_cmd) 184 { 185 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 186 struct fc_frame *fp; 187 struct fcp_txrdy *txrdy; 188 struct fc_lport *lport; 189 struct fc_exch *ep; 190 struct fc_frame_header *fh; 191 u32 f_ctl; 192 193 ft_dump_cmd(cmd, __func__); 194 195 ep = fc_seq_exch(cmd->seq); 196 lport = ep->lp; 197 fp = fc_frame_alloc(lport, sizeof(*txrdy)); 198 if (!fp) 199 return -ENOMEM; /* Signal QUEUE_FULL */ 200 201 txrdy = fc_frame_payload_get(fp, sizeof(*txrdy)); 202 memset(txrdy, 0, sizeof(*txrdy)); 203 txrdy->ft_burst_len = htonl(se_cmd->data_length); 204 205 cmd->seq = lport->tt.seq_start_next(cmd->seq); 206 fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP, 207 FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); 208 209 fh = fc_frame_header_get(fp); 210 f_ctl = ntoh24(fh->fh_f_ctl); 211 212 /* Only if it is 'Exchange Responder' */ 213 if (f_ctl & FC_FC_EX_CTX) { 214 /* Target is 'exchange responder' and sending XFER_READY 215 * to 'exchange initiator (initiator)' 216 */ 217 if ((ep->xid <= lport->lro_xid) && 218 (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) { 219 if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) { 220 /* 221 * cmd may have been broken up into multiple 222 * tasks. Link their sgs together so we can 223 * operate on them all at once. 224 */ 225 transport_do_task_sg_chain(se_cmd); 226 cmd->sg = se_cmd->t_tasks_sg_chained; 227 cmd->sg_cnt = 228 se_cmd->t_tasks_sg_chained_no; 229 } 230 if (cmd->sg && lport->tt.ddp_target(lport, ep->xid, 231 cmd->sg, 232 cmd->sg_cnt)) 233 cmd->was_ddp_setup = 1; 234 } 235 } 236 lport->tt.seq_send(lport, cmd->seq, fp); 237 return 0; 238 } 239 240 u32 ft_get_task_tag(struct se_cmd *se_cmd) 241 { 242 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 243 244 return fc_seq_exch(cmd->seq)->rxid; 245 } 246 247 int ft_get_cmd_state(struct se_cmd *se_cmd) 248 { 249 return 0; 250 } 251 252 int ft_is_state_remove(struct se_cmd *se_cmd) 253 { 254 return 0; /* XXX TBD */ 255 } 256 257 /* 258 * FC sequence response handler for follow-on sequences (data) and aborts. 259 */ 260 static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg) 261 { 262 struct ft_cmd *cmd = arg; 263 struct fc_frame_header *fh; 264 265 if (IS_ERR(fp)) { 266 /* XXX need to find cmd if queued */ 267 cmd->seq = NULL; 268 transport_generic_free_cmd(&cmd->se_cmd, 0); 269 return; 270 } 271 272 fh = fc_frame_header_get(fp); 273 274 switch (fh->fh_r_ctl) { 275 case FC_RCTL_DD_SOL_DATA: /* write data */ 276 ft_recv_write_data(cmd, fp); 277 break; 278 case FC_RCTL_DD_UNSOL_CTL: /* command */ 279 case FC_RCTL_DD_SOL_CTL: /* transfer ready */ 280 case FC_RCTL_DD_DATA_DESC: /* transfer ready */ 281 default: 282 pr_debug("%s: unhandled frame r_ctl %x\n", 283 __func__, fh->fh_r_ctl); 284 ft_invl_hw_context(cmd); 285 fc_frame_free(fp); 286 transport_generic_free_cmd(&cmd->se_cmd, 0); 287 break; 288 } 289 } 290 291 /* 292 * Send a FCP response including SCSI status and optional FCP rsp_code. 293 * status is SAM_STAT_GOOD (zero) iff code is valid. 294 * This is used in error cases, such as allocation failures. 295 */ 296 static void ft_send_resp_status(struct fc_lport *lport, 297 const struct fc_frame *rx_fp, 298 u32 status, enum fcp_resp_rsp_codes code) 299 { 300 struct fc_frame *fp; 301 struct fc_seq *sp; 302 const struct fc_frame_header *fh; 303 size_t len; 304 struct fcp_resp_with_ext *fcp; 305 struct fcp_resp_rsp_info *info; 306 307 fh = fc_frame_header_get(rx_fp); 308 pr_debug("FCP error response: did %x oxid %x status %x code %x\n", 309 ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code); 310 len = sizeof(*fcp); 311 if (status == SAM_STAT_GOOD) 312 len += sizeof(*info); 313 fp = fc_frame_alloc(lport, len); 314 if (!fp) 315 return; 316 fcp = fc_frame_payload_get(fp, len); 317 memset(fcp, 0, len); 318 fcp->resp.fr_status = status; 319 if (status == SAM_STAT_GOOD) { 320 fcp->ext.fr_rsp_len = htonl(sizeof(*info)); 321 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL; 322 info = (struct fcp_resp_rsp_info *)(fcp + 1); 323 info->rsp_code = code; 324 } 325 326 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0); 327 sp = fr_seq(fp); 328 if (sp) 329 lport->tt.seq_send(lport, sp, fp); 330 else 331 lport->tt.frame_send(lport, fp); 332 } 333 334 /* 335 * Send error or task management response. 336 */ 337 static void ft_send_resp_code(struct ft_cmd *cmd, 338 enum fcp_resp_rsp_codes code) 339 { 340 ft_send_resp_status(cmd->sess->tport->lport, 341 cmd->req_frame, SAM_STAT_GOOD, code); 342 } 343 344 345 /* 346 * Send error or task management response. 347 * Always frees the cmd and associated state. 348 */ 349 static void ft_send_resp_code_and_free(struct ft_cmd *cmd, 350 enum fcp_resp_rsp_codes code) 351 { 352 ft_send_resp_code(cmd, code); 353 ft_free_cmd(cmd); 354 } 355 356 /* 357 * Handle Task Management Request. 358 */ 359 static void ft_send_tm(struct ft_cmd *cmd) 360 { 361 struct se_tmr_req *tmr; 362 struct fcp_cmnd *fcp; 363 struct ft_sess *sess; 364 u8 tm_func; 365 366 transport_init_se_cmd(&cmd->se_cmd, &ft_configfs->tf_ops, 367 cmd->sess->se_sess, 0, DMA_NONE, 0, 368 &cmd->ft_sense_buffer[0]); 369 target_get_sess_cmd(cmd->sess->se_sess, &cmd->se_cmd, false); 370 371 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp)); 372 373 switch (fcp->fc_tm_flags) { 374 case FCP_TMF_LUN_RESET: 375 tm_func = TMR_LUN_RESET; 376 break; 377 case FCP_TMF_TGT_RESET: 378 tm_func = TMR_TARGET_WARM_RESET; 379 break; 380 case FCP_TMF_CLR_TASK_SET: 381 tm_func = TMR_CLEAR_TASK_SET; 382 break; 383 case FCP_TMF_ABT_TASK_SET: 384 tm_func = TMR_ABORT_TASK_SET; 385 break; 386 case FCP_TMF_CLR_ACA: 387 tm_func = TMR_CLEAR_ACA; 388 break; 389 default: 390 /* 391 * FCP4r01 indicates having a combination of 392 * tm_flags set is invalid. 393 */ 394 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags); 395 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); 396 return; 397 } 398 399 pr_debug("alloc tm cmd fn %d\n", tm_func); 400 tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func, GFP_KERNEL); 401 if (!tmr) { 402 pr_debug("alloc failed\n"); 403 ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED); 404 return; 405 } 406 cmd->se_cmd.se_tmr_req = tmr; 407 408 switch (fcp->fc_tm_flags) { 409 case FCP_TMF_LUN_RESET: 410 cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun); 411 if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) { 412 /* 413 * Make sure to clean up newly allocated TMR request 414 * since "unable to handle TMR request because failed 415 * to get to LUN" 416 */ 417 pr_debug("Failed to get LUN for TMR func %d, " 418 "se_cmd %p, unpacked_lun %d\n", 419 tm_func, &cmd->se_cmd, cmd->lun); 420 ft_dump_cmd(cmd, __func__); 421 sess = cmd->sess; 422 transport_send_check_condition_and_sense(&cmd->se_cmd, 423 cmd->se_cmd.scsi_sense_reason, 0); 424 ft_sess_put(sess); 425 return; 426 } 427 break; 428 case FCP_TMF_TGT_RESET: 429 case FCP_TMF_CLR_TASK_SET: 430 case FCP_TMF_ABT_TASK_SET: 431 case FCP_TMF_CLR_ACA: 432 break; 433 default: 434 return; 435 } 436 transport_generic_handle_tmr(&cmd->se_cmd); 437 } 438 439 /* 440 * Send status from completed task management request. 441 */ 442 int ft_queue_tm_resp(struct se_cmd *se_cmd) 443 { 444 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 445 struct se_tmr_req *tmr = se_cmd->se_tmr_req; 446 enum fcp_resp_rsp_codes code; 447 448 switch (tmr->response) { 449 case TMR_FUNCTION_COMPLETE: 450 code = FCP_TMF_CMPL; 451 break; 452 case TMR_LUN_DOES_NOT_EXIST: 453 code = FCP_TMF_INVALID_LUN; 454 break; 455 case TMR_FUNCTION_REJECTED: 456 code = FCP_TMF_REJECTED; 457 break; 458 case TMR_TASK_DOES_NOT_EXIST: 459 case TMR_TASK_STILL_ALLEGIANT: 460 case TMR_TASK_FAILOVER_NOT_SUPPORTED: 461 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED: 462 case TMR_FUNCTION_AUTHORIZATION_FAILED: 463 default: 464 code = FCP_TMF_FAILED; 465 break; 466 } 467 pr_debug("tmr fn %d resp %d fcp code %d\n", 468 tmr->function, tmr->response, code); 469 ft_send_resp_code(cmd, code); 470 return 0; 471 } 472 473 static void ft_send_work(struct work_struct *work); 474 475 /* 476 * Handle incoming FCP command. 477 */ 478 static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp) 479 { 480 struct ft_cmd *cmd; 481 struct fc_lport *lport = sess->tport->lport; 482 483 cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC); 484 if (!cmd) 485 goto busy; 486 cmd->sess = sess; 487 cmd->seq = lport->tt.seq_assign(lport, fp); 488 if (!cmd->seq) { 489 kfree(cmd); 490 goto busy; 491 } 492 cmd->req_frame = fp; /* hold frame during cmd */ 493 494 INIT_WORK(&cmd->work, ft_send_work); 495 queue_work(sess->tport->tpg->workqueue, &cmd->work); 496 return; 497 498 busy: 499 pr_debug("cmd or seq allocation failure - sending BUSY\n"); 500 ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0); 501 fc_frame_free(fp); 502 ft_sess_put(sess); /* undo get from lookup */ 503 } 504 505 506 /* 507 * Handle incoming FCP frame. 508 * Caller has verified that the frame is type FCP. 509 */ 510 void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp) 511 { 512 struct fc_frame_header *fh = fc_frame_header_get(fp); 513 514 switch (fh->fh_r_ctl) { 515 case FC_RCTL_DD_UNSOL_CMD: /* command */ 516 ft_recv_cmd(sess, fp); 517 break; 518 case FC_RCTL_DD_SOL_DATA: /* write data */ 519 case FC_RCTL_DD_UNSOL_CTL: 520 case FC_RCTL_DD_SOL_CTL: 521 case FC_RCTL_DD_DATA_DESC: /* transfer ready */ 522 case FC_RCTL_ELS4_REQ: /* SRR, perhaps */ 523 default: 524 pr_debug("%s: unhandled frame r_ctl %x\n", 525 __func__, fh->fh_r_ctl); 526 fc_frame_free(fp); 527 ft_sess_put(sess); /* undo get from lookup */ 528 break; 529 } 530 } 531 532 /* 533 * Send new command to target. 534 */ 535 static void ft_send_work(struct work_struct *work) 536 { 537 struct ft_cmd *cmd = container_of(work, struct ft_cmd, work); 538 struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame); 539 struct fcp_cmnd *fcp; 540 int data_dir = 0; 541 u32 data_len; 542 int task_attr; 543 int ret; 544 545 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp)); 546 if (!fcp) 547 goto err; 548 549 if (fcp->fc_flags & FCP_CFL_LEN_MASK) 550 goto err; /* not handling longer CDBs yet */ 551 552 if (fcp->fc_tm_flags) { 553 task_attr = FCP_PTA_SIMPLE; 554 data_dir = DMA_NONE; 555 data_len = 0; 556 } else { 557 switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) { 558 case 0: 559 data_dir = DMA_NONE; 560 break; 561 case FCP_CFL_RDDATA: 562 data_dir = DMA_FROM_DEVICE; 563 break; 564 case FCP_CFL_WRDATA: 565 data_dir = DMA_TO_DEVICE; 566 break; 567 case FCP_CFL_WRDATA | FCP_CFL_RDDATA: 568 goto err; /* TBD not supported by tcm_fc yet */ 569 } 570 /* 571 * Locate the SAM Task Attr from fc_pri_ta 572 */ 573 switch (fcp->fc_pri_ta & FCP_PTA_MASK) { 574 case FCP_PTA_HEADQ: 575 task_attr = MSG_HEAD_TAG; 576 break; 577 case FCP_PTA_ORDERED: 578 task_attr = MSG_ORDERED_TAG; 579 break; 580 case FCP_PTA_ACA: 581 task_attr = MSG_ACA_TAG; 582 break; 583 case FCP_PTA_SIMPLE: /* Fallthrough */ 584 default: 585 task_attr = MSG_SIMPLE_TAG; 586 } 587 588 589 task_attr = fcp->fc_pri_ta & FCP_PTA_MASK; 590 data_len = ntohl(fcp->fc_dl); 591 cmd->cdb = fcp->fc_cdb; 592 } 593 /* 594 * Check for FCP task management flags 595 */ 596 if (fcp->fc_tm_flags) { 597 ft_send_tm(cmd); 598 return; 599 } 600 fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd); 601 cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun); 602 /* 603 * Use a single se_cmd->cmd_kref as we expect to release se_cmd 604 * directly from ft_check_stop_free callback in response path. 605 */ 606 ret = target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, cmd->cdb, 607 &cmd->ft_sense_buffer[0], cmd->lun, data_len, 608 task_attr, data_dir, 0); 609 pr_debug("r_ctl %x alloc target_submit_cmd %d\n", fh->fh_r_ctl, ret); 610 if (ret < 0) { 611 ft_dump_cmd(cmd, __func__); 612 return; 613 } 614 return; 615 616 err: 617 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); 618 } 619