1 /******************************************************************************* 2 * Filename: target_core_tmr.c 3 * 4 * This file contains SPC-3 task management infrastructure 5 * 6 * Copyright (c) 2009,2010 Rising Tide Systems 7 * Copyright (c) 2009,2010 Linux-iSCSI.org 8 * 9 * Nicholas A. Bellinger <nab@kernel.org> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 24 * 25 ******************************************************************************/ 26 27 #include <linux/slab.h> 28 #include <linux/spinlock.h> 29 #include <linux/list.h> 30 #include <linux/export.h> 31 #include <scsi/scsi.h> 32 #include <scsi/scsi_cmnd.h> 33 34 #include <target/target_core_base.h> 35 #include <target/target_core_backend.h> 36 #include <target/target_core_fabric.h> 37 #include <target/target_core_configfs.h> 38 39 #include "target_core_internal.h" 40 #include "target_core_alua.h" 41 #include "target_core_pr.h" 42 43 int core_tmr_alloc_req( 44 struct se_cmd *se_cmd, 45 void *fabric_tmr_ptr, 46 u8 function, 47 gfp_t gfp_flags) 48 { 49 struct se_tmr_req *tmr; 50 51 tmr = kzalloc(sizeof(struct se_tmr_req), gfp_flags); 52 if (!tmr) { 53 pr_err("Unable to allocate struct se_tmr_req\n"); 54 return -ENOMEM; 55 } 56 57 se_cmd->se_cmd_flags |= SCF_SCSI_TMR_CDB; 58 se_cmd->se_tmr_req = tmr; 59 tmr->task_cmd = se_cmd; 60 tmr->fabric_tmr_ptr = fabric_tmr_ptr; 61 tmr->function = function; 62 INIT_LIST_HEAD(&tmr->tmr_list); 63 64 return 0; 65 } 66 EXPORT_SYMBOL(core_tmr_alloc_req); 67 68 void core_tmr_release_req( 69 struct se_tmr_req *tmr) 70 { 71 struct se_device *dev = tmr->tmr_dev; 72 unsigned long flags; 73 74 if (!dev) { 75 kfree(tmr); 76 return; 77 } 78 79 spin_lock_irqsave(&dev->se_tmr_lock, flags); 80 list_del(&tmr->tmr_list); 81 spin_unlock_irqrestore(&dev->se_tmr_lock, flags); 82 83 kfree(tmr); 84 } 85 86 static void core_tmr_handle_tas_abort( 87 struct se_node_acl *tmr_nacl, 88 struct se_cmd *cmd, 89 int tas, 90 int fe_count) 91 { 92 if (!fe_count) { 93 transport_cmd_finish_abort(cmd, 1); 94 return; 95 } 96 /* 97 * TASK ABORTED status (TAS) bit support 98 */ 99 if ((tmr_nacl && 100 (tmr_nacl == cmd->se_sess->se_node_acl)) || tas) 101 transport_send_task_abort(cmd); 102 103 transport_cmd_finish_abort(cmd, 0); 104 } 105 106 static int target_check_cdb_and_preempt(struct list_head *list, 107 struct se_cmd *cmd) 108 { 109 struct t10_pr_registration *reg; 110 111 if (!list) 112 return 0; 113 list_for_each_entry(reg, list, pr_reg_abort_list) { 114 if (reg->pr_res_key == cmd->pr_res_key) 115 return 0; 116 } 117 118 return 1; 119 } 120 121 void core_tmr_abort_task( 122 struct se_device *dev, 123 struct se_tmr_req *tmr, 124 struct se_session *se_sess) 125 { 126 struct se_cmd *se_cmd, *tmp_cmd; 127 unsigned long flags; 128 int ref_tag; 129 130 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); 131 list_for_each_entry_safe(se_cmd, tmp_cmd, 132 &se_sess->sess_cmd_list, se_cmd_list) { 133 134 if (dev != se_cmd->se_dev) 135 continue; 136 ref_tag = se_cmd->se_tfo->get_task_tag(se_cmd); 137 if (tmr->ref_task_tag != ref_tag) 138 continue; 139 140 printk("ABORT_TASK: Found referenced %s task_tag: %u\n", 141 se_cmd->se_tfo->get_fabric_name(), ref_tag); 142 143 spin_lock_irq(&se_cmd->t_state_lock); 144 if (se_cmd->transport_state & CMD_T_COMPLETE) { 145 printk("ABORT_TASK: ref_tag: %u already complete, skipping\n", ref_tag); 146 spin_unlock_irq(&se_cmd->t_state_lock); 147 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); 148 goto out; 149 } 150 se_cmd->transport_state |= CMD_T_ABORTED; 151 spin_unlock_irq(&se_cmd->t_state_lock); 152 153 list_del_init(&se_cmd->se_cmd_list); 154 kref_get(&se_cmd->cmd_kref); 155 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); 156 157 cancel_work_sync(&se_cmd->work); 158 transport_wait_for_tasks(se_cmd); 159 /* 160 * Now send SAM_STAT_TASK_ABORTED status for the referenced 161 * se_cmd descriptor.. 162 */ 163 transport_send_task_abort(se_cmd); 164 /* 165 * Also deal with possible extra acknowledge reference.. 166 */ 167 if (se_cmd->se_cmd_flags & SCF_ACK_KREF) 168 target_put_sess_cmd(se_sess, se_cmd); 169 170 target_put_sess_cmd(se_sess, se_cmd); 171 172 printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for" 173 " ref_tag: %d\n", ref_tag); 174 tmr->response = TMR_FUNCTION_COMPLETE; 175 return; 176 } 177 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); 178 179 out: 180 printk("ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST for ref_tag: %d\n", 181 tmr->ref_task_tag); 182 tmr->response = TMR_TASK_DOES_NOT_EXIST; 183 } 184 185 static void core_tmr_drain_tmr_list( 186 struct se_device *dev, 187 struct se_tmr_req *tmr, 188 struct list_head *preempt_and_abort_list) 189 { 190 LIST_HEAD(drain_tmr_list); 191 struct se_tmr_req *tmr_p, *tmr_pp; 192 struct se_cmd *cmd; 193 unsigned long flags; 194 /* 195 * Release all pending and outgoing TMRs aside from the received 196 * LUN_RESET tmr.. 197 */ 198 spin_lock_irqsave(&dev->se_tmr_lock, flags); 199 list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) { 200 /* 201 * Allow the received TMR to return with FUNCTION_COMPLETE. 202 */ 203 if (tmr_p == tmr) 204 continue; 205 206 cmd = tmr_p->task_cmd; 207 if (!cmd) { 208 pr_err("Unable to locate struct se_cmd for TMR\n"); 209 continue; 210 } 211 /* 212 * If this function was called with a valid pr_res_key 213 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action 214 * skip non regisration key matching TMRs. 215 */ 216 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd)) 217 continue; 218 219 spin_lock(&cmd->t_state_lock); 220 if (!(cmd->transport_state & CMD_T_ACTIVE)) { 221 spin_unlock(&cmd->t_state_lock); 222 continue; 223 } 224 if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) { 225 spin_unlock(&cmd->t_state_lock); 226 continue; 227 } 228 spin_unlock(&cmd->t_state_lock); 229 230 list_move_tail(&tmr_p->tmr_list, &drain_tmr_list); 231 } 232 spin_unlock_irqrestore(&dev->se_tmr_lock, flags); 233 234 list_for_each_entry_safe(tmr_p, tmr_pp, &drain_tmr_list, tmr_list) { 235 list_del_init(&tmr_p->tmr_list); 236 cmd = tmr_p->task_cmd; 237 238 pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x," 239 " Response: 0x%02x, t_state: %d\n", 240 (preempt_and_abort_list) ? "Preempt" : "", tmr_p, 241 tmr_p->function, tmr_p->response, cmd->t_state); 242 243 transport_cmd_finish_abort(cmd, 1); 244 } 245 } 246 247 static void core_tmr_drain_task_list( 248 struct se_device *dev, 249 struct se_cmd *prout_cmd, 250 struct se_node_acl *tmr_nacl, 251 int tas, 252 struct list_head *preempt_and_abort_list) 253 { 254 LIST_HEAD(drain_task_list); 255 struct se_cmd *cmd; 256 struct se_task *task, *task_tmp; 257 unsigned long flags; 258 int fe_count; 259 /* 260 * Complete outstanding struct se_task CDBs with TASK_ABORTED SAM status. 261 * This is following sam4r17, section 5.6 Aborting commands, Table 38 262 * for TMR LUN_RESET: 263 * 264 * a) "Yes" indicates that each command that is aborted on an I_T nexus 265 * other than the one that caused the SCSI device condition is 266 * completed with TASK ABORTED status, if the TAS bit is set to one in 267 * the Control mode page (see SPC-4). "No" indicates that no status is 268 * returned for aborted commands. 269 * 270 * d) If the logical unit reset is caused by a particular I_T nexus 271 * (e.g., by a LOGICAL UNIT RESET task management function), then "yes" 272 * (TASK_ABORTED status) applies. 273 * 274 * Otherwise (e.g., if triggered by a hard reset), "no" 275 * (no TASK_ABORTED SAM status) applies. 276 * 277 * Note that this seems to be independent of TAS (Task Aborted Status) 278 * in the Control Mode Page. 279 */ 280 spin_lock_irqsave(&dev->execute_task_lock, flags); 281 list_for_each_entry_safe(task, task_tmp, &dev->state_task_list, 282 t_state_list) { 283 if (!task->task_se_cmd) { 284 pr_err("task->task_se_cmd is NULL!\n"); 285 continue; 286 } 287 cmd = task->task_se_cmd; 288 289 /* 290 * For PREEMPT_AND_ABORT usage, only process commands 291 * with a matching reservation key. 292 */ 293 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd)) 294 continue; 295 /* 296 * Not aborting PROUT PREEMPT_AND_ABORT CDB.. 297 */ 298 if (prout_cmd == cmd) 299 continue; 300 301 list_move_tail(&task->t_state_list, &drain_task_list); 302 task->t_state_active = false; 303 /* 304 * Remove from task execute list before processing drain_task_list 305 */ 306 if (!list_empty(&task->t_execute_list)) 307 __transport_remove_task_from_execute_queue(task, dev); 308 } 309 spin_unlock_irqrestore(&dev->execute_task_lock, flags); 310 311 while (!list_empty(&drain_task_list)) { 312 task = list_entry(drain_task_list.next, struct se_task, t_state_list); 313 list_del(&task->t_state_list); 314 cmd = task->task_se_cmd; 315 316 pr_debug("LUN_RESET: %s cmd: %p task: %p" 317 " ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state: %d" 318 "cdb: 0x%02x\n", 319 (preempt_and_abort_list) ? "Preempt" : "", cmd, task, 320 cmd->se_tfo->get_task_tag(cmd), 0, 321 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state, 322 cmd->t_task_cdb[0]); 323 pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx" 324 " t_task_cdbs: %d t_task_cdbs_left: %d" 325 " t_task_cdbs_sent: %d -- CMD_T_ACTIVE: %d" 326 " CMD_T_STOP: %d CMD_T_SENT: %d\n", 327 cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key, 328 cmd->t_task_list_num, 329 atomic_read(&cmd->t_task_cdbs_left), 330 atomic_read(&cmd->t_task_cdbs_sent), 331 (cmd->transport_state & CMD_T_ACTIVE) != 0, 332 (cmd->transport_state & CMD_T_STOP) != 0, 333 (cmd->transport_state & CMD_T_SENT) != 0); 334 335 /* 336 * If the command may be queued onto a workqueue cancel it now. 337 * 338 * This is equivalent to removal from the execute queue in the 339 * loop above, but we do it down here given that 340 * cancel_work_sync may block. 341 */ 342 if (cmd->t_state == TRANSPORT_COMPLETE) 343 cancel_work_sync(&cmd->work); 344 345 spin_lock_irqsave(&cmd->t_state_lock, flags); 346 target_stop_task(task, &flags); 347 348 if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) { 349 spin_unlock_irqrestore(&cmd->t_state_lock, flags); 350 pr_debug("LUN_RESET: Skipping task: %p, dev: %p for" 351 " t_task_cdbs_ex_left: %d\n", task, dev, 352 atomic_read(&cmd->t_task_cdbs_ex_left)); 353 continue; 354 } 355 fe_count = atomic_read(&cmd->t_fe_count); 356 357 if (!(cmd->transport_state & CMD_T_ACTIVE)) { 358 pr_debug("LUN_RESET: got CMD_T_ACTIVE for" 359 " task: %p, t_fe_count: %d dev: %p\n", task, 360 fe_count, dev); 361 cmd->transport_state |= CMD_T_ABORTED; 362 spin_unlock_irqrestore(&cmd->t_state_lock, flags); 363 364 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); 365 continue; 366 } 367 pr_debug("LUN_RESET: Got !CMD_T_ACTIVE for task: %p," 368 " t_fe_count: %d dev: %p\n", task, fe_count, dev); 369 cmd->transport_state |= CMD_T_ABORTED; 370 spin_unlock_irqrestore(&cmd->t_state_lock, flags); 371 372 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); 373 } 374 } 375 376 static void core_tmr_drain_cmd_list( 377 struct se_device *dev, 378 struct se_cmd *prout_cmd, 379 struct se_node_acl *tmr_nacl, 380 int tas, 381 struct list_head *preempt_and_abort_list) 382 { 383 LIST_HEAD(drain_cmd_list); 384 struct se_queue_obj *qobj = &dev->dev_queue_obj; 385 struct se_cmd *cmd, *tcmd; 386 unsigned long flags; 387 /* 388 * Release all commands remaining in the struct se_device cmd queue. 389 * 390 * This follows the same logic as above for the struct se_device 391 * struct se_task state list, where commands are returned with 392 * TASK_ABORTED status, if there is an outstanding $FABRIC_MOD 393 * reference, otherwise the struct se_cmd is released. 394 */ 395 spin_lock_irqsave(&qobj->cmd_queue_lock, flags); 396 list_for_each_entry_safe(cmd, tcmd, &qobj->qobj_list, se_queue_node) { 397 /* 398 * For PREEMPT_AND_ABORT usage, only process commands 399 * with a matching reservation key. 400 */ 401 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd)) 402 continue; 403 /* 404 * Not aborting PROUT PREEMPT_AND_ABORT CDB.. 405 */ 406 if (prout_cmd == cmd) 407 continue; 408 409 cmd->transport_state &= ~CMD_T_QUEUED; 410 atomic_dec(&qobj->queue_cnt); 411 list_move_tail(&cmd->se_queue_node, &drain_cmd_list); 412 } 413 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags); 414 415 while (!list_empty(&drain_cmd_list)) { 416 cmd = list_entry(drain_cmd_list.next, struct se_cmd, se_queue_node); 417 list_del_init(&cmd->se_queue_node); 418 419 pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:" 420 " %d t_fe_count: %d\n", (preempt_and_abort_list) ? 421 "Preempt" : "", cmd, cmd->t_state, 422 atomic_read(&cmd->t_fe_count)); 423 424 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, 425 atomic_read(&cmd->t_fe_count)); 426 } 427 } 428 429 int core_tmr_lun_reset( 430 struct se_device *dev, 431 struct se_tmr_req *tmr, 432 struct list_head *preempt_and_abort_list, 433 struct se_cmd *prout_cmd) 434 { 435 struct se_node_acl *tmr_nacl = NULL; 436 struct se_portal_group *tmr_tpg = NULL; 437 int tas; 438 /* 439 * TASK_ABORTED status bit, this is configurable via ConfigFS 440 * struct se_device attributes. spc4r17 section 7.4.6 Control mode page 441 * 442 * A task aborted status (TAS) bit set to zero specifies that aborted 443 * tasks shall be terminated by the device server without any response 444 * to the application client. A TAS bit set to one specifies that tasks 445 * aborted by the actions of an I_T nexus other than the I_T nexus on 446 * which the command was received shall be completed with TASK ABORTED 447 * status (see SAM-4). 448 */ 449 tas = dev->se_sub_dev->se_dev_attrib.emulate_tas; 450 /* 451 * Determine if this se_tmr is coming from a $FABRIC_MOD 452 * or struct se_device passthrough.. 453 */ 454 if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) { 455 tmr_nacl = tmr->task_cmd->se_sess->se_node_acl; 456 tmr_tpg = tmr->task_cmd->se_sess->se_tpg; 457 if (tmr_nacl && tmr_tpg) { 458 pr_debug("LUN_RESET: TMR caller fabric: %s" 459 " initiator port %s\n", 460 tmr_tpg->se_tpg_tfo->get_fabric_name(), 461 tmr_nacl->initiatorname); 462 } 463 } 464 pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n", 465 (preempt_and_abort_list) ? "Preempt" : "TMR", 466 dev->transport->name, tas); 467 468 core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list); 469 core_tmr_drain_task_list(dev, prout_cmd, tmr_nacl, tas, 470 preempt_and_abort_list); 471 core_tmr_drain_cmd_list(dev, prout_cmd, tmr_nacl, tas, 472 preempt_and_abort_list); 473 /* 474 * Clear any legacy SPC-2 reservation when called during 475 * LOGICAL UNIT RESET 476 */ 477 if (!preempt_and_abort_list && 478 (dev->dev_flags & DF_SPC2_RESERVATIONS)) { 479 spin_lock(&dev->dev_reservation_lock); 480 dev->dev_reserved_node_acl = NULL; 481 dev->dev_flags &= ~DF_SPC2_RESERVATIONS; 482 spin_unlock(&dev->dev_reservation_lock); 483 pr_debug("LUN_RESET: SCSI-2 Released reservation\n"); 484 } 485 486 spin_lock_irq(&dev->stats_lock); 487 dev->num_resets++; 488 spin_unlock_irq(&dev->stats_lock); 489 490 pr_debug("LUN_RESET: %s for [%s] Complete\n", 491 (preempt_and_abort_list) ? "Preempt" : "TMR", 492 dev->transport->name); 493 return 0; 494 } 495 496