| 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_state_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, *next; |
| 256 | unsigned long flags; |
| 257 | int fe_count; |
| 258 | |
| 259 | /* |
| 260 | * Complete outstanding commands with TASK_ABORTED SAM status. |
| 261 | * |
| 262 | * This is following sam4r17, section 5.6 Aborting commands, Table 38 |
| 263 | * for TMR LUN_RESET: |
| 264 | * |
| 265 | * a) "Yes" indicates that each command that is aborted on an I_T nexus |
| 266 | * other than the one that caused the SCSI device condition is |
| 267 | * completed with TASK ABORTED status, if the TAS bit is set to one in |
| 268 | * the Control mode page (see SPC-4). "No" indicates that no status is |
| 269 | * returned for aborted commands. |
| 270 | * |
| 271 | * d) If the logical unit reset is caused by a particular I_T nexus |
| 272 | * (e.g., by a LOGICAL UNIT RESET task management function), then "yes" |
| 273 | * (TASK_ABORTED status) applies. |
| 274 | * |
| 275 | * Otherwise (e.g., if triggered by a hard reset), "no" |
| 276 | * (no TASK_ABORTED SAM status) applies. |
| 277 | * |
| 278 | * Note that this seems to be independent of TAS (Task Aborted Status) |
| 279 | * in the Control Mode Page. |
| 280 | */ |
| 281 | spin_lock_irqsave(&dev->execute_task_lock, flags); |
| 282 | list_for_each_entry_safe(cmd, next, &dev->state_list, state_list) { |
| 283 | /* |
| 284 | * For PREEMPT_AND_ABORT usage, only process commands |
| 285 | * with a matching reservation key. |
| 286 | */ |
| 287 | if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd)) |
| 288 | continue; |
| 289 | |
| 290 | /* |
| 291 | * Not aborting PROUT PREEMPT_AND_ABORT CDB.. |
| 292 | */ |
| 293 | if (prout_cmd == cmd) |
| 294 | continue; |
| 295 | |
| 296 | list_move_tail(&cmd->state_list, &drain_task_list); |
| 297 | cmd->state_active = false; |
| 298 | } |
| 299 | spin_unlock_irqrestore(&dev->execute_task_lock, flags); |
| 300 | |
| 301 | while (!list_empty(&drain_task_list)) { |
| 302 | cmd = list_entry(drain_task_list.next, struct se_cmd, state_list); |
| 303 | list_del(&cmd->state_list); |
| 304 | |
| 305 | pr_debug("LUN_RESET: %s cmd: %p" |
| 306 | " ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state: %d" |
| 307 | "cdb: 0x%02x\n", |
| 308 | (preempt_and_abort_list) ? "Preempt" : "", cmd, |
| 309 | cmd->se_tfo->get_task_tag(cmd), 0, |
| 310 | cmd->se_tfo->get_cmd_state(cmd), cmd->t_state, |
| 311 | cmd->t_task_cdb[0]); |
| 312 | pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx" |
| 313 | " -- CMD_T_ACTIVE: %d" |
| 314 | " CMD_T_STOP: %d CMD_T_SENT: %d\n", |
| 315 | cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key, |
| 316 | (cmd->transport_state & CMD_T_ACTIVE) != 0, |
| 317 | (cmd->transport_state & CMD_T_STOP) != 0, |
| 318 | (cmd->transport_state & CMD_T_SENT) != 0); |
| 319 | |
| 320 | /* |
| 321 | * If the command may be queued onto a workqueue cancel it now. |
| 322 | * |
| 323 | * This is equivalent to removal from the execute queue in the |
| 324 | * loop above, but we do it down here given that |
| 325 | * cancel_work_sync may block. |
| 326 | */ |
| 327 | if (cmd->t_state == TRANSPORT_COMPLETE) |
| 328 | cancel_work_sync(&cmd->work); |
| 329 | |
| 330 | spin_lock_irqsave(&cmd->t_state_lock, flags); |
| 331 | target_stop_cmd(cmd, &flags); |
| 332 | |
| 333 | fe_count = atomic_read(&cmd->t_fe_count); |
| 334 | |
| 335 | if (!(cmd->transport_state & CMD_T_ACTIVE)) { |
| 336 | pr_debug("LUN_RESET: got CMD_T_ACTIVE for" |
| 337 | " cdb: %p, t_fe_count: %d dev: %p\n", cmd, |
| 338 | fe_count, dev); |
| 339 | cmd->transport_state |= CMD_T_ABORTED; |
| 340 | spin_unlock_irqrestore(&cmd->t_state_lock, flags); |
| 341 | |
| 342 | core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); |
| 343 | continue; |
| 344 | } |
| 345 | pr_debug("LUN_RESET: Got !CMD_T_ACTIVE for cdb: %p," |
| 346 | " t_fe_count: %d dev: %p\n", cmd, fe_count, dev); |
| 347 | cmd->transport_state |= CMD_T_ABORTED; |
| 348 | spin_unlock_irqrestore(&cmd->t_state_lock, flags); |
| 349 | |
| 350 | core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); |
| 351 | } |
| 352 | } |
| 353 | |
| 354 | int core_tmr_lun_reset( |
| 355 | struct se_device *dev, |
| 356 | struct se_tmr_req *tmr, |
| 357 | struct list_head *preempt_and_abort_list, |
| 358 | struct se_cmd *prout_cmd) |
| 359 | { |
| 360 | struct se_node_acl *tmr_nacl = NULL; |
| 361 | struct se_portal_group *tmr_tpg = NULL; |
| 362 | int tas; |
| 363 | /* |
| 364 | * TASK_ABORTED status bit, this is configurable via ConfigFS |
| 365 | * struct se_device attributes. spc4r17 section 7.4.6 Control mode page |
| 366 | * |
| 367 | * A task aborted status (TAS) bit set to zero specifies that aborted |
| 368 | * tasks shall be terminated by the device server without any response |
| 369 | * to the application client. A TAS bit set to one specifies that tasks |
| 370 | * aborted by the actions of an I_T nexus other than the I_T nexus on |
| 371 | * which the command was received shall be completed with TASK ABORTED |
| 372 | * status (see SAM-4). |
| 373 | */ |
| 374 | tas = dev->se_sub_dev->se_dev_attrib.emulate_tas; |
| 375 | /* |
| 376 | * Determine if this se_tmr is coming from a $FABRIC_MOD |
| 377 | * or struct se_device passthrough.. |
| 378 | */ |
| 379 | if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) { |
| 380 | tmr_nacl = tmr->task_cmd->se_sess->se_node_acl; |
| 381 | tmr_tpg = tmr->task_cmd->se_sess->se_tpg; |
| 382 | if (tmr_nacl && tmr_tpg) { |
| 383 | pr_debug("LUN_RESET: TMR caller fabric: %s" |
| 384 | " initiator port %s\n", |
| 385 | tmr_tpg->se_tpg_tfo->get_fabric_name(), |
| 386 | tmr_nacl->initiatorname); |
| 387 | } |
| 388 | } |
| 389 | pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n", |
| 390 | (preempt_and_abort_list) ? "Preempt" : "TMR", |
| 391 | dev->transport->name, tas); |
| 392 | |
| 393 | core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list); |
| 394 | core_tmr_drain_state_list(dev, prout_cmd, tmr_nacl, tas, |
| 395 | preempt_and_abort_list); |
| 396 | |
| 397 | /* |
| 398 | * Clear any legacy SPC-2 reservation when called during |
| 399 | * LOGICAL UNIT RESET |
| 400 | */ |
| 401 | if (!preempt_and_abort_list && |
| 402 | (dev->dev_flags & DF_SPC2_RESERVATIONS)) { |
| 403 | spin_lock(&dev->dev_reservation_lock); |
| 404 | dev->dev_reserved_node_acl = NULL; |
| 405 | dev->dev_flags &= ~DF_SPC2_RESERVATIONS; |
| 406 | spin_unlock(&dev->dev_reservation_lock); |
| 407 | pr_debug("LUN_RESET: SCSI-2 Released reservation\n"); |
| 408 | } |
| 409 | |
| 410 | spin_lock_irq(&dev->stats_lock); |
| 411 | dev->num_resets++; |
| 412 | spin_unlock_irq(&dev->stats_lock); |
| 413 | |
| 414 | pr_debug("LUN_RESET: %s for [%s] Complete\n", |
| 415 | (preempt_and_abort_list) ? "Preempt" : "TMR", |
| 416 | dev->transport->name); |
| 417 | return 0; |
| 418 | } |
| 419 | |