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