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 <asm/unaligned.h> 32 #include <scsi/scsi_tcq.h> 33 #include <scsi/libfc.h> 34 #include <scsi/fc_encode.h> 35 36 #include <target/target_core_base.h> 37 #include <target/target_core_fabric.h> 38 39 #include "tcm_fc.h" 40 41 /* 42 * Dump cmd state for debugging. 43 */ 44 static void _ft_dump_cmd(struct ft_cmd *cmd, const char *caller) 45 { 46 struct fc_exch *ep; 47 struct fc_seq *sp; 48 struct se_cmd *se_cmd; 49 struct scatterlist *sg; 50 int count; 51 52 se_cmd = &cmd->se_cmd; 53 pr_debug("%s: cmd %p sess %p seq %p se_cmd %p\n", 54 caller, cmd, cmd->sess, cmd->seq, se_cmd); 55 56 pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n", 57 caller, cmd, se_cmd->t_data_nents, 58 se_cmd->data_length, se_cmd->se_cmd_flags); 59 60 for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count) 61 pr_debug("%s: cmd %p sg %p page %p " 62 "len 0x%x off 0x%x\n", 63 caller, cmd, sg, 64 sg_page(sg), sg->length, sg->offset); 65 66 sp = cmd->seq; 67 if (sp) { 68 ep = fc_seq_exch(sp); 69 pr_debug("%s: cmd %p sid %x did %x " 70 "ox_id %x rx_id %x seq_id %x e_stat %x\n", 71 caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid, 72 sp->id, ep->esb_stat); 73 } 74 } 75 76 void ft_dump_cmd(struct ft_cmd *cmd, const char *caller) 77 { 78 if (unlikely(ft_debug_logging)) 79 _ft_dump_cmd(cmd, caller); 80 } 81 82 static void ft_free_cmd(struct ft_cmd *cmd) 83 { 84 struct fc_frame *fp; 85 struct ft_sess *sess; 86 87 if (!cmd) 88 return; 89 sess = cmd->sess; 90 fp = cmd->req_frame; 91 if (fr_seq(fp)) 92 fc_seq_release(fr_seq(fp)); 93 fc_frame_free(fp); 94 target_free_tag(sess->se_sess, &cmd->se_cmd); 95 ft_sess_put(sess); /* undo get from lookup at recv */ 96 } 97 98 void ft_release_cmd(struct se_cmd *se_cmd) 99 { 100 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 101 102 ft_free_cmd(cmd); 103 } 104 105 int ft_check_stop_free(struct se_cmd *se_cmd) 106 { 107 return transport_generic_free_cmd(se_cmd, 0); 108 } 109 110 /* 111 * Send response. 112 */ 113 int ft_queue_status(struct se_cmd *se_cmd) 114 { 115 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 116 struct fc_frame *fp; 117 struct fcp_resp_with_ext *fcp; 118 struct fc_lport *lport; 119 struct fc_exch *ep; 120 size_t len; 121 int rc; 122 123 if (cmd->aborted) 124 return 0; 125 ft_dump_cmd(cmd, __func__); 126 ep = fc_seq_exch(cmd->seq); 127 lport = ep->lp; 128 len = sizeof(*fcp) + se_cmd->scsi_sense_length; 129 fp = fc_frame_alloc(lport, len); 130 if (!fp) { 131 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL; 132 return -ENOMEM; 133 } 134 135 fcp = fc_frame_payload_get(fp, len); 136 memset(fcp, 0, len); 137 fcp->resp.fr_status = se_cmd->scsi_status; 138 139 len = se_cmd->scsi_sense_length; 140 if (len) { 141 fcp->resp.fr_flags |= FCP_SNS_LEN_VAL; 142 fcp->ext.fr_sns_len = htonl(len); 143 memcpy((fcp + 1), se_cmd->sense_buffer, len); 144 } 145 146 /* 147 * Test underflow and overflow with one mask. Usually both are off. 148 * Bidirectional commands are not handled yet. 149 */ 150 if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) { 151 if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) 152 fcp->resp.fr_flags |= FCP_RESID_OVER; 153 else 154 fcp->resp.fr_flags |= FCP_RESID_UNDER; 155 fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count); 156 } 157 158 /* 159 * Send response. 160 */ 161 cmd->seq = fc_seq_start_next(cmd->seq); 162 fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP, 163 FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0); 164 165 rc = fc_seq_send(lport, cmd->seq, fp); 166 if (rc) { 167 pr_info_ratelimited("%s: Failed to send response frame %p, " 168 "xid <0x%x>\n", __func__, fp, ep->xid); 169 /* 170 * Generate a TASK_SET_FULL status to notify the initiator 171 * to reduce it's queue_depth after the se_cmd response has 172 * been re-queued by target-core. 173 */ 174 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL; 175 return -ENOMEM; 176 } 177 fc_exch_done(cmd->seq); 178 /* 179 * Drop the extra ACK_KREF reference taken by target_submit_cmd() 180 * ahead of ft_check_stop_free() -> transport_generic_free_cmd() 181 * final se_cmd->cmd_kref put. 182 */ 183 target_put_sess_cmd(&cmd->se_cmd); 184 return 0; 185 } 186 187 int ft_write_pending_status(struct se_cmd *se_cmd) 188 { 189 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 190 191 return cmd->write_data_len != se_cmd->data_length; 192 } 193 194 /* 195 * Send TX_RDY (transfer ready). 196 */ 197 int ft_write_pending(struct se_cmd *se_cmd) 198 { 199 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 200 struct fc_frame *fp; 201 struct fcp_txrdy *txrdy; 202 struct fc_lport *lport; 203 struct fc_exch *ep; 204 struct fc_frame_header *fh; 205 u32 f_ctl; 206 207 ft_dump_cmd(cmd, __func__); 208 209 if (cmd->aborted) 210 return 0; 211 ep = fc_seq_exch(cmd->seq); 212 lport = ep->lp; 213 fp = fc_frame_alloc(lport, sizeof(*txrdy)); 214 if (!fp) 215 return -ENOMEM; /* Signal QUEUE_FULL */ 216 217 txrdy = fc_frame_payload_get(fp, sizeof(*txrdy)); 218 memset(txrdy, 0, sizeof(*txrdy)); 219 txrdy->ft_burst_len = htonl(se_cmd->data_length); 220 221 cmd->seq = fc_seq_start_next(cmd->seq); 222 fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP, 223 FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); 224 225 fh = fc_frame_header_get(fp); 226 f_ctl = ntoh24(fh->fh_f_ctl); 227 228 /* Only if it is 'Exchange Responder' */ 229 if (f_ctl & FC_FC_EX_CTX) { 230 /* Target is 'exchange responder' and sending XFER_READY 231 * to 'exchange initiator (initiator)' 232 */ 233 if ((ep->xid <= lport->lro_xid) && 234 (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) { 235 if ((se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && 236 lport->tt.ddp_target(lport, ep->xid, 237 se_cmd->t_data_sg, 238 se_cmd->t_data_nents)) 239 cmd->was_ddp_setup = 1; 240 } 241 } 242 fc_seq_send(lport, cmd->seq, fp); 243 return 0; 244 } 245 246 int ft_get_cmd_state(struct se_cmd *se_cmd) 247 { 248 return 0; 249 } 250 251 /* 252 * FC sequence response handler for follow-on sequences (data) and aborts. 253 */ 254 static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg) 255 { 256 struct ft_cmd *cmd = arg; 257 struct fc_frame_header *fh; 258 259 if (IS_ERR(fp)) { 260 /* XXX need to find cmd if queued */ 261 cmd->seq = NULL; 262 cmd->aborted = true; 263 return; 264 } 265 266 fh = fc_frame_header_get(fp); 267 268 switch (fh->fh_r_ctl) { 269 case FC_RCTL_DD_SOL_DATA: /* write data */ 270 ft_recv_write_data(cmd, fp); 271 break; 272 case FC_RCTL_DD_UNSOL_CTL: /* command */ 273 case FC_RCTL_DD_SOL_CTL: /* transfer ready */ 274 case FC_RCTL_DD_DATA_DESC: /* transfer ready */ 275 default: 276 pr_debug("%s: unhandled frame r_ctl %x\n", 277 __func__, fh->fh_r_ctl); 278 ft_invl_hw_context(cmd); 279 fc_frame_free(fp); 280 transport_generic_free_cmd(&cmd->se_cmd, 0); 281 break; 282 } 283 } 284 285 /* 286 * Send a FCP response including SCSI status and optional FCP rsp_code. 287 * status is SAM_STAT_GOOD (zero) iff code is valid. 288 * This is used in error cases, such as allocation failures. 289 */ 290 static void ft_send_resp_status(struct fc_lport *lport, 291 const struct fc_frame *rx_fp, 292 u32 status, enum fcp_resp_rsp_codes code) 293 { 294 struct fc_frame *fp; 295 struct fc_seq *sp; 296 const struct fc_frame_header *fh; 297 size_t len; 298 struct fcp_resp_with_ext *fcp; 299 struct fcp_resp_rsp_info *info; 300 301 fh = fc_frame_header_get(rx_fp); 302 pr_debug("FCP error response: did %x oxid %x status %x code %x\n", 303 ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code); 304 len = sizeof(*fcp); 305 if (status == SAM_STAT_GOOD) 306 len += sizeof(*info); 307 fp = fc_frame_alloc(lport, len); 308 if (!fp) 309 return; 310 fcp = fc_frame_payload_get(fp, len); 311 memset(fcp, 0, len); 312 fcp->resp.fr_status = status; 313 if (status == SAM_STAT_GOOD) { 314 fcp->ext.fr_rsp_len = htonl(sizeof(*info)); 315 fcp->resp.fr_flags |= FCP_RSP_LEN_VAL; 316 info = (struct fcp_resp_rsp_info *)(fcp + 1); 317 info->rsp_code = code; 318 } 319 320 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0); 321 sp = fr_seq(fp); 322 if (sp) { 323 fc_seq_send(lport, sp, fp); 324 fc_exch_done(sp); 325 } else { 326 lport->tt.frame_send(lport, fp); 327 } 328 } 329 330 /* 331 * Send error or task management response. 332 */ 333 static void ft_send_resp_code(struct ft_cmd *cmd, 334 enum fcp_resp_rsp_codes code) 335 { 336 ft_send_resp_status(cmd->sess->tport->lport, 337 cmd->req_frame, SAM_STAT_GOOD, code); 338 } 339 340 341 /* 342 * Send error or task management response. 343 * Always frees the cmd and associated state. 344 */ 345 static void ft_send_resp_code_and_free(struct ft_cmd *cmd, 346 enum fcp_resp_rsp_codes code) 347 { 348 ft_send_resp_code(cmd, code); 349 ft_free_cmd(cmd); 350 } 351 352 /* 353 * Handle Task Management Request. 354 */ 355 static void ft_send_tm(struct ft_cmd *cmd) 356 { 357 struct fcp_cmnd *fcp; 358 int rc; 359 u8 tm_func; 360 361 fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp)); 362 363 switch (fcp->fc_tm_flags) { 364 case FCP_TMF_LUN_RESET: 365 tm_func = TMR_LUN_RESET; 366 break; 367 case FCP_TMF_TGT_RESET: 368 tm_func = TMR_TARGET_WARM_RESET; 369 break; 370 case FCP_TMF_CLR_TASK_SET: 371 tm_func = TMR_CLEAR_TASK_SET; 372 break; 373 case FCP_TMF_ABT_TASK_SET: 374 tm_func = TMR_ABORT_TASK_SET; 375 break; 376 case FCP_TMF_CLR_ACA: 377 tm_func = TMR_CLEAR_ACA; 378 break; 379 default: 380 /* 381 * FCP4r01 indicates having a combination of 382 * tm_flags set is invalid. 383 */ 384 pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags); 385 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); 386 return; 387 } 388 389 /* FIXME: Add referenced task tag for ABORT_TASK */ 390 rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess, 391 &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun), 392 cmd, tm_func, GFP_KERNEL, 0, TARGET_SCF_ACK_KREF); 393 if (rc < 0) 394 ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED); 395 } 396 397 /* 398 * Send status from completed task management request. 399 */ 400 void ft_queue_tm_resp(struct se_cmd *se_cmd) 401 { 402 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); 403 struct se_tmr_req *tmr = se_cmd->se_tmr_req; 404 enum fcp_resp_rsp_codes code; 405 406 if (cmd->aborted) 407 return; 408 switch (tmr->response) { 409 case TMR_FUNCTION_COMPLETE: 410 code = FCP_TMF_CMPL; 411 break; 412 case TMR_LUN_DOES_NOT_EXIST: 413 code = FCP_TMF_INVALID_LUN; 414 break; 415 case TMR_FUNCTION_REJECTED: 416 code = FCP_TMF_REJECTED; 417 break; 418 case TMR_TASK_DOES_NOT_EXIST: 419 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED: 420 default: 421 code = FCP_TMF_FAILED; 422 break; 423 } 424 pr_debug("tmr fn %d resp %d fcp code %d\n", 425 tmr->function, tmr->response, code); 426 ft_send_resp_code(cmd, code); 427 /* 428 * Drop the extra ACK_KREF reference taken by target_submit_tmr() 429 * ahead of ft_check_stop_free() -> transport_generic_free_cmd() 430 * final se_cmd->cmd_kref put. 431 */ 432 target_put_sess_cmd(&cmd->se_cmd); 433 } 434 435 void ft_aborted_task(struct se_cmd *se_cmd) 436 { 437 return; 438 } 439 440 static void ft_send_work(struct work_struct *work); 441 442 /* 443 * Handle incoming FCP command. 444 */ 445 static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp) 446 { 447 struct ft_cmd *cmd; 448 struct fc_lport *lport = sess->tport->lport; 449 struct se_session *se_sess = sess->se_sess; 450 int tag, cpu; 451 452 tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu); 453 if (tag < 0) 454 goto busy; 455 456 cmd = &((struct ft_cmd *)se_sess->sess_cmd_map)[tag]; 457 memset(cmd, 0, sizeof(struct ft_cmd)); 458 459 cmd->se_cmd.map_tag = tag; 460 cmd->se_cmd.map_cpu = cpu; 461 cmd->sess = sess; 462 cmd->seq = fc_seq_assign(lport, fp); 463 if (!cmd->seq) { 464 target_free_tag(se_sess, &cmd->se_cmd); 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; 472 473 busy: 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 */ 485 void 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 */ 510 static 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; 578 579 err: 580 ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); 581 } 582