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1// SPDX-License-Identifier: GPL-2.0-only2/*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 else141 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 initiator158 * to reduce it's queue_depth after the se_cmd response has159 * 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_READY211 * 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 of357 * 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 flags502 */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_ta523 */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_cmd544 * 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}563