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_device.h> 36 #include <target/target_core_tmr.h> 37 #include <target/target_core_transport.h> 38 #include <target/target_core_fabric_ops.h> 39 #include <target/target_core_configfs.h> 40 41 #include "target_core_alua.h" 42 #include "target_core_pr.h" 43 44 struct se_tmr_req *core_tmr_alloc_req( 45 struct se_cmd *se_cmd, 46 void *fabric_tmr_ptr, 47 u8 function, 48 gfp_t gfp_flags) 49 { 50 struct se_tmr_req *tmr; 51 52 tmr = kmem_cache_zalloc(se_tmr_req_cache, gfp_flags); 53 if (!tmr) { 54 pr_err("Unable to allocate struct se_tmr_req\n"); 55 return ERR_PTR(-ENOMEM); 56 } 57 tmr->task_cmd = se_cmd; 58 tmr->fabric_tmr_ptr = fabric_tmr_ptr; 59 tmr->function = function; 60 INIT_LIST_HEAD(&tmr->tmr_list); 61 62 return tmr; 63 } 64 EXPORT_SYMBOL(core_tmr_alloc_req); 65 66 void core_tmr_release_req( 67 struct se_tmr_req *tmr) 68 { 69 struct se_device *dev = tmr->tmr_dev; 70 unsigned long flags; 71 72 if (!dev) { 73 kmem_cache_free(se_tmr_req_cache, tmr); 74 return; 75 } 76 77 spin_lock_irqsave(&dev->se_tmr_lock, flags); 78 list_del(&tmr->tmr_list); 79 spin_unlock_irqrestore(&dev->se_tmr_lock, flags); 80 81 kmem_cache_free(se_tmr_req_cache, tmr); 82 } 83 84 static void core_tmr_handle_tas_abort( 85 struct se_node_acl *tmr_nacl, 86 struct se_cmd *cmd, 87 int tas, 88 int fe_count) 89 { 90 if (!fe_count) { 91 transport_cmd_finish_abort(cmd, 1); 92 return; 93 } 94 /* 95 * TASK ABORTED status (TAS) bit support 96 */ 97 if ((tmr_nacl && 98 (tmr_nacl == cmd->se_sess->se_node_acl)) || tas) 99 transport_send_task_abort(cmd); 100 101 transport_cmd_finish_abort(cmd, 0); 102 } 103 104 static void core_tmr_drain_tmr_list( 105 struct se_device *dev, 106 struct se_tmr_req *tmr, 107 struct list_head *preempt_and_abort_list) 108 { 109 LIST_HEAD(drain_tmr_list); 110 struct se_tmr_req *tmr_p, *tmr_pp; 111 struct se_cmd *cmd; 112 unsigned long flags; 113 /* 114 * Release all pending and outgoing TMRs aside from the received 115 * LUN_RESET tmr.. 116 */ 117 spin_lock_irqsave(&dev->se_tmr_lock, flags); 118 list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) { 119 /* 120 * Allow the received TMR to return with FUNCTION_COMPLETE. 121 */ 122 if (tmr_p == tmr) 123 continue; 124 125 cmd = tmr_p->task_cmd; 126 if (!cmd) { 127 pr_err("Unable to locate struct se_cmd for TMR\n"); 128 continue; 129 } 130 /* 131 * If this function was called with a valid pr_res_key 132 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action 133 * skip non regisration key matching TMRs. 134 */ 135 if (preempt_and_abort_list && 136 (core_scsi3_check_cdb_abort_and_preempt( 137 preempt_and_abort_list, cmd) != 0)) 138 continue; 139 140 spin_lock(&cmd->t_state_lock); 141 if (!atomic_read(&cmd->t_transport_active)) { 142 spin_unlock(&cmd->t_state_lock); 143 continue; 144 } 145 if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) { 146 spin_unlock(&cmd->t_state_lock); 147 continue; 148 } 149 spin_unlock(&cmd->t_state_lock); 150 151 list_move_tail(&tmr_p->tmr_list, &drain_tmr_list); 152 } 153 spin_unlock_irqrestore(&dev->se_tmr_lock, flags); 154 155 list_for_each_entry_safe(tmr_p, tmr_pp, &drain_tmr_list, tmr_list) { 156 list_del_init(&tmr_p->tmr_list); 157 cmd = tmr_p->task_cmd; 158 159 pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x," 160 " Response: 0x%02x, t_state: %d\n", 161 (preempt_and_abort_list) ? "Preempt" : "", tmr_p, 162 tmr_p->function, tmr_p->response, cmd->t_state); 163 164 transport_cmd_finish_abort(cmd, 1); 165 } 166 } 167 168 static void core_tmr_drain_task_list( 169 struct se_device *dev, 170 struct se_cmd *prout_cmd, 171 struct se_node_acl *tmr_nacl, 172 int tas, 173 struct list_head *preempt_and_abort_list) 174 { 175 LIST_HEAD(drain_task_list); 176 struct se_cmd *cmd; 177 struct se_task *task, *task_tmp; 178 unsigned long flags; 179 int fe_count; 180 /* 181 * Complete outstanding struct se_task CDBs with TASK_ABORTED SAM status. 182 * This is following sam4r17, section 5.6 Aborting commands, Table 38 183 * for TMR LUN_RESET: 184 * 185 * a) "Yes" indicates that each command that is aborted on an I_T nexus 186 * other than the one that caused the SCSI device condition is 187 * completed with TASK ABORTED status, if the TAS bit is set to one in 188 * the Control mode page (see SPC-4). "No" indicates that no status is 189 * returned for aborted commands. 190 * 191 * d) If the logical unit reset is caused by a particular I_T nexus 192 * (e.g., by a LOGICAL UNIT RESET task management function), then "yes" 193 * (TASK_ABORTED status) applies. 194 * 195 * Otherwise (e.g., if triggered by a hard reset), "no" 196 * (no TASK_ABORTED SAM status) applies. 197 * 198 * Note that this seems to be independent of TAS (Task Aborted Status) 199 * in the Control Mode Page. 200 */ 201 spin_lock_irqsave(&dev->execute_task_lock, flags); 202 list_for_each_entry_safe(task, task_tmp, &dev->state_task_list, 203 t_state_list) { 204 if (!task->task_se_cmd) { 205 pr_err("task->task_se_cmd is NULL!\n"); 206 continue; 207 } 208 cmd = task->task_se_cmd; 209 210 /* 211 * For PREEMPT_AND_ABORT usage, only process commands 212 * with a matching reservation key. 213 */ 214 if (preempt_and_abort_list && 215 (core_scsi3_check_cdb_abort_and_preempt( 216 preempt_and_abort_list, cmd) != 0)) 217 continue; 218 /* 219 * Not aborting PROUT PREEMPT_AND_ABORT CDB.. 220 */ 221 if (prout_cmd == cmd) 222 continue; 223 224 list_move_tail(&task->t_state_list, &drain_task_list); 225 atomic_set(&task->task_state_active, 0); 226 /* 227 * Remove from task execute list before processing drain_task_list 228 */ 229 if (!list_empty(&task->t_execute_list)) 230 __transport_remove_task_from_execute_queue(task, dev); 231 } 232 spin_unlock_irqrestore(&dev->execute_task_lock, flags); 233 234 while (!list_empty(&drain_task_list)) { 235 task = list_entry(drain_task_list.next, struct se_task, t_state_list); 236 list_del(&task->t_state_list); 237 cmd = task->task_se_cmd; 238 239 pr_debug("LUN_RESET: %s cmd: %p task: %p" 240 " ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state: %d" 241 "cdb: 0x%02x\n", 242 (preempt_and_abort_list) ? "Preempt" : "", cmd, task, 243 cmd->se_tfo->get_task_tag(cmd), 0, 244 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state, 245 cmd->t_task_cdb[0]); 246 pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx" 247 " t_task_cdbs: %d t_task_cdbs_left: %d" 248 " t_task_cdbs_sent: %d -- t_transport_active: %d" 249 " t_transport_stop: %d t_transport_sent: %d\n", 250 cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key, 251 cmd->t_task_list_num, 252 atomic_read(&cmd->t_task_cdbs_left), 253 atomic_read(&cmd->t_task_cdbs_sent), 254 atomic_read(&cmd->t_transport_active), 255 atomic_read(&cmd->t_transport_stop), 256 atomic_read(&cmd->t_transport_sent)); 257 258 /* 259 * If the command may be queued onto a workqueue cancel it now. 260 * 261 * This is equivalent to removal from the execute queue in the 262 * loop above, but we do it down here given that 263 * cancel_work_sync may block. 264 */ 265 if (cmd->t_state == TRANSPORT_COMPLETE) 266 cancel_work_sync(&cmd->work); 267 268 spin_lock_irqsave(&cmd->t_state_lock, flags); 269 target_stop_task(task, &flags); 270 271 if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) { 272 spin_unlock_irqrestore(&cmd->t_state_lock, flags); 273 pr_debug("LUN_RESET: Skipping task: %p, dev: %p for" 274 " t_task_cdbs_ex_left: %d\n", task, dev, 275 atomic_read(&cmd->t_task_cdbs_ex_left)); 276 continue; 277 } 278 fe_count = atomic_read(&cmd->t_fe_count); 279 280 if (atomic_read(&cmd->t_transport_active)) { 281 pr_debug("LUN_RESET: got t_transport_active = 1 for" 282 " task: %p, t_fe_count: %d dev: %p\n", task, 283 fe_count, dev); 284 atomic_set(&cmd->t_transport_aborted, 1); 285 spin_unlock_irqrestore(&cmd->t_state_lock, flags); 286 287 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); 288 continue; 289 } 290 pr_debug("LUN_RESET: Got t_transport_active = 0 for task: %p," 291 " t_fe_count: %d dev: %p\n", task, fe_count, dev); 292 atomic_set(&cmd->t_transport_aborted, 1); 293 spin_unlock_irqrestore(&cmd->t_state_lock, flags); 294 295 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); 296 } 297 } 298 299 static void core_tmr_drain_cmd_list( 300 struct se_device *dev, 301 struct se_cmd *prout_cmd, 302 struct se_node_acl *tmr_nacl, 303 int tas, 304 struct list_head *preempt_and_abort_list) 305 { 306 LIST_HEAD(drain_cmd_list); 307 struct se_queue_obj *qobj = &dev->dev_queue_obj; 308 struct se_cmd *cmd, *tcmd; 309 unsigned long flags; 310 /* 311 * Release all commands remaining in the struct se_device cmd queue. 312 * 313 * This follows the same logic as above for the struct se_device 314 * struct se_task state list, where commands are returned with 315 * TASK_ABORTED status, if there is an outstanding $FABRIC_MOD 316 * reference, otherwise the struct se_cmd is released. 317 */ 318 spin_lock_irqsave(&qobj->cmd_queue_lock, flags); 319 list_for_each_entry_safe(cmd, tcmd, &qobj->qobj_list, se_queue_node) { 320 /* 321 * For PREEMPT_AND_ABORT usage, only process commands 322 * with a matching reservation key. 323 */ 324 if (preempt_and_abort_list && 325 (core_scsi3_check_cdb_abort_and_preempt( 326 preempt_and_abort_list, cmd) != 0)) 327 continue; 328 /* 329 * Not aborting PROUT PREEMPT_AND_ABORT CDB.. 330 */ 331 if (prout_cmd == cmd) 332 continue; 333 334 atomic_set(&cmd->t_transport_queue_active, 0); 335 atomic_dec(&qobj->queue_cnt); 336 list_move_tail(&cmd->se_queue_node, &drain_cmd_list); 337 } 338 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags); 339 340 while (!list_empty(&drain_cmd_list)) { 341 cmd = list_entry(drain_cmd_list.next, struct se_cmd, se_queue_node); 342 list_del_init(&cmd->se_queue_node); 343 344 pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:" 345 " %d t_fe_count: %d\n", (preempt_and_abort_list) ? 346 "Preempt" : "", cmd, cmd->t_state, 347 atomic_read(&cmd->t_fe_count)); 348 /* 349 * Signal that the command has failed via cmd->se_cmd_flags, 350 */ 351 transport_new_cmd_failure(cmd); 352 353 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, 354 atomic_read(&cmd->t_fe_count)); 355 } 356 } 357 358 int core_tmr_lun_reset( 359 struct se_device *dev, 360 struct se_tmr_req *tmr, 361 struct list_head *preempt_and_abort_list, 362 struct se_cmd *prout_cmd) 363 { 364 struct se_node_acl *tmr_nacl = NULL; 365 struct se_portal_group *tmr_tpg = NULL; 366 int tas; 367 /* 368 * TASK_ABORTED status bit, this is configurable via ConfigFS 369 * struct se_device attributes. spc4r17 section 7.4.6 Control mode page 370 * 371 * A task aborted status (TAS) bit set to zero specifies that aborted 372 * tasks shall be terminated by the device server without any response 373 * to the application client. A TAS bit set to one specifies that tasks 374 * aborted by the actions of an I_T nexus other than the I_T nexus on 375 * which the command was received shall be completed with TASK ABORTED 376 * status (see SAM-4). 377 */ 378 tas = dev->se_sub_dev->se_dev_attrib.emulate_tas; 379 /* 380 * Determine if this se_tmr is coming from a $FABRIC_MOD 381 * or struct se_device passthrough.. 382 */ 383 if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) { 384 tmr_nacl = tmr->task_cmd->se_sess->se_node_acl; 385 tmr_tpg = tmr->task_cmd->se_sess->se_tpg; 386 if (tmr_nacl && tmr_tpg) { 387 pr_debug("LUN_RESET: TMR caller fabric: %s" 388 " initiator port %s\n", 389 tmr_tpg->se_tpg_tfo->get_fabric_name(), 390 tmr_nacl->initiatorname); 391 } 392 } 393 pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n", 394 (preempt_and_abort_list) ? "Preempt" : "TMR", 395 dev->transport->name, tas); 396 397 core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list); 398 core_tmr_drain_task_list(dev, prout_cmd, tmr_nacl, tas, 399 preempt_and_abort_list); 400 core_tmr_drain_cmd_list(dev, prout_cmd, tmr_nacl, tas, 401 preempt_and_abort_list); 402 /* 403 * Clear any legacy SPC-2 reservation when called during 404 * LOGICAL UNIT RESET 405 */ 406 if (!preempt_and_abort_list && 407 (dev->dev_flags & DF_SPC2_RESERVATIONS)) { 408 spin_lock(&dev->dev_reservation_lock); 409 dev->dev_reserved_node_acl = NULL; 410 dev->dev_flags &= ~DF_SPC2_RESERVATIONS; 411 spin_unlock(&dev->dev_reservation_lock); 412 pr_debug("LUN_RESET: SCSI-2 Released reservation\n"); 413 } 414 415 spin_lock_irq(&dev->stats_lock); 416 dev->num_resets++; 417 spin_unlock_irq(&dev->stats_lock); 418 419 pr_debug("LUN_RESET: %s for [%s] Complete\n", 420 (preempt_and_abort_list) ? "Preempt" : "TMR", 421 dev->transport->name); 422 return 0; 423 } 424 425