1 /*******************************************************************************
2 * Filename: target_core_tmr.c
4 * This file contains SPC-3 task management infrastructure
6 * (c) Copyright 2009-2013 Datera, Inc.
8 * Nicholas A. Bellinger <nab@kernel.org>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 ******************************************************************************/
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 #include <linux/list.h>
29 #include <linux/export.h>
30 #include <scsi/scsi.h>
31 #include <scsi/scsi_cmnd.h>
33 #include <target/target_core_base.h>
34 #include <target/target_core_backend.h>
35 #include <target/target_core_fabric.h>
36 #include <target/target_core_configfs.h>
38 #include "target_core_internal.h"
39 #include "target_core_alua.h"
40 #include "target_core_pr.h"
42 int core_tmr_alloc_req(
43 struct se_cmd *se_cmd,
48 struct se_tmr_req *tmr;
50 tmr = kzalloc(sizeof(struct se_tmr_req), gfp_flags);
52 pr_err("Unable to allocate struct se_tmr_req\n");
56 se_cmd->se_cmd_flags |= SCF_SCSI_TMR_CDB;
57 se_cmd->se_tmr_req = tmr;
58 tmr->task_cmd = se_cmd;
59 tmr->fabric_tmr_ptr = fabric_tmr_ptr;
60 tmr->function = function;
61 INIT_LIST_HEAD(&tmr->tmr_list);
65 EXPORT_SYMBOL(core_tmr_alloc_req);
67 void core_tmr_release_req(struct se_tmr_req *tmr)
69 struct se_device *dev = tmr->tmr_dev;
73 spin_lock_irqsave(&dev->se_tmr_lock, flags);
74 list_del(&tmr->tmr_list);
75 spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
81 static void core_tmr_handle_tas_abort(
82 struct se_node_acl *tmr_nacl,
88 * TASK ABORTED status (TAS) bit support
90 if ((tmr_nacl && (tmr_nacl != cmd->se_sess->se_node_acl)) && tas) {
92 transport_send_task_abort(cmd);
95 transport_cmd_finish_abort(cmd, remove);
98 static int target_check_cdb_and_preempt(struct list_head *list,
101 struct t10_pr_registration *reg;
105 list_for_each_entry(reg, list, pr_reg_abort_list) {
106 if (reg->pr_res_key == cmd->pr_res_key)
113 void core_tmr_abort_task(
114 struct se_device *dev,
115 struct se_tmr_req *tmr,
116 struct se_session *se_sess)
118 struct se_cmd *se_cmd;
122 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
123 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
125 if (dev != se_cmd->se_dev)
128 /* skip se_cmd associated with tmr */
129 if (tmr->task_cmd == se_cmd)
132 ref_tag = se_cmd->se_tfo->get_task_tag(se_cmd);
133 if (tmr->ref_task_tag != ref_tag)
136 printk("ABORT_TASK: Found referenced %s task_tag: %u\n",
137 se_cmd->se_tfo->get_fabric_name(), ref_tag);
139 spin_lock(&se_cmd->t_state_lock);
140 if (se_cmd->transport_state & CMD_T_COMPLETE) {
141 printk("ABORT_TASK: ref_tag: %u already complete, skipping\n", ref_tag);
142 spin_unlock(&se_cmd->t_state_lock);
143 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
146 se_cmd->transport_state |= CMD_T_ABORTED;
147 spin_unlock(&se_cmd->t_state_lock);
149 list_del_init(&se_cmd->se_cmd_list);
150 kref_get(&se_cmd->cmd_kref);
151 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
153 cancel_work_sync(&se_cmd->work);
154 transport_wait_for_tasks(se_cmd);
156 target_put_sess_cmd(se_sess, se_cmd);
157 transport_cmd_finish_abort(se_cmd, true);
159 printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for"
160 " ref_tag: %d\n", ref_tag);
161 tmr->response = TMR_FUNCTION_COMPLETE;
164 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
167 printk("ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST for ref_tag: %d\n",
169 tmr->response = TMR_TASK_DOES_NOT_EXIST;
172 static void core_tmr_drain_tmr_list(
173 struct se_device *dev,
174 struct se_tmr_req *tmr,
175 struct list_head *preempt_and_abort_list)
177 LIST_HEAD(drain_tmr_list);
178 struct se_tmr_req *tmr_p, *tmr_pp;
182 * Release all pending and outgoing TMRs aside from the received
185 spin_lock_irqsave(&dev->se_tmr_lock, flags);
186 list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
188 * Allow the received TMR to return with FUNCTION_COMPLETE.
193 cmd = tmr_p->task_cmd;
195 pr_err("Unable to locate struct se_cmd for TMR\n");
199 * If this function was called with a valid pr_res_key
200 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action
201 * skip non regisration key matching TMRs.
203 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
206 spin_lock(&cmd->t_state_lock);
207 if (!(cmd->transport_state & CMD_T_ACTIVE)) {
208 spin_unlock(&cmd->t_state_lock);
211 if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
212 spin_unlock(&cmd->t_state_lock);
215 spin_unlock(&cmd->t_state_lock);
217 list_move_tail(&tmr_p->tmr_list, &drain_tmr_list);
219 spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
221 list_for_each_entry_safe(tmr_p, tmr_pp, &drain_tmr_list, tmr_list) {
222 list_del_init(&tmr_p->tmr_list);
223 cmd = tmr_p->task_cmd;
225 pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
226 " Response: 0x%02x, t_state: %d\n",
227 (preempt_and_abort_list) ? "Preempt" : "", tmr_p,
228 tmr_p->function, tmr_p->response, cmd->t_state);
230 transport_cmd_finish_abort(cmd, 1);
234 static void core_tmr_drain_state_list(
235 struct se_device *dev,
236 struct se_cmd *prout_cmd,
237 struct se_node_acl *tmr_nacl,
239 struct list_head *preempt_and_abort_list)
241 LIST_HEAD(drain_task_list);
242 struct se_cmd *cmd, *next;
246 * Complete outstanding commands with TASK_ABORTED SAM status.
248 * This is following sam4r17, section 5.6 Aborting commands, Table 38
251 * a) "Yes" indicates that each command that is aborted on an I_T nexus
252 * other than the one that caused the SCSI device condition is
253 * completed with TASK ABORTED status, if the TAS bit is set to one in
254 * the Control mode page (see SPC-4). "No" indicates that no status is
255 * returned for aborted commands.
257 * d) If the logical unit reset is caused by a particular I_T nexus
258 * (e.g., by a LOGICAL UNIT RESET task management function), then "yes"
259 * (TASK_ABORTED status) applies.
261 * Otherwise (e.g., if triggered by a hard reset), "no"
262 * (no TASK_ABORTED SAM status) applies.
264 * Note that this seems to be independent of TAS (Task Aborted Status)
265 * in the Control Mode Page.
267 spin_lock_irqsave(&dev->execute_task_lock, flags);
268 list_for_each_entry_safe(cmd, next, &dev->state_list, state_list) {
270 * For PREEMPT_AND_ABORT usage, only process commands
271 * with a matching reservation key.
273 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
277 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
279 if (prout_cmd == cmd)
282 list_move_tail(&cmd->state_list, &drain_task_list);
283 cmd->state_active = false;
285 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
287 while (!list_empty(&drain_task_list)) {
288 cmd = list_entry(drain_task_list.next, struct se_cmd, state_list);
289 list_del(&cmd->state_list);
291 pr_debug("LUN_RESET: %s cmd: %p"
292 " ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state: %d"
294 (preempt_and_abort_list) ? "Preempt" : "", cmd,
295 cmd->se_tfo->get_task_tag(cmd), 0,
296 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
298 pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx"
299 " -- CMD_T_ACTIVE: %d"
300 " CMD_T_STOP: %d CMD_T_SENT: %d\n",
301 cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key,
302 (cmd->transport_state & CMD_T_ACTIVE) != 0,
303 (cmd->transport_state & CMD_T_STOP) != 0,
304 (cmd->transport_state & CMD_T_SENT) != 0);
307 * If the command may be queued onto a workqueue cancel it now.
309 * This is equivalent to removal from the execute queue in the
310 * loop above, but we do it down here given that
311 * cancel_work_sync may block.
313 if (cmd->t_state == TRANSPORT_COMPLETE)
314 cancel_work_sync(&cmd->work);
316 spin_lock_irqsave(&cmd->t_state_lock, flags);
317 target_stop_cmd(cmd, &flags);
319 cmd->transport_state |= CMD_T_ABORTED;
320 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
322 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas);
326 int core_tmr_lun_reset(
327 struct se_device *dev,
328 struct se_tmr_req *tmr,
329 struct list_head *preempt_and_abort_list,
330 struct se_cmd *prout_cmd)
332 struct se_node_acl *tmr_nacl = NULL;
333 struct se_portal_group *tmr_tpg = NULL;
336 * TASK_ABORTED status bit, this is configurable via ConfigFS
337 * struct se_device attributes. spc4r17 section 7.4.6 Control mode page
339 * A task aborted status (TAS) bit set to zero specifies that aborted
340 * tasks shall be terminated by the device server without any response
341 * to the application client. A TAS bit set to one specifies that tasks
342 * aborted by the actions of an I_T nexus other than the I_T nexus on
343 * which the command was received shall be completed with TASK ABORTED
344 * status (see SAM-4).
346 tas = dev->dev_attrib.emulate_tas;
348 * Determine if this se_tmr is coming from a $FABRIC_MOD
349 * or struct se_device passthrough..
351 if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) {
352 tmr_nacl = tmr->task_cmd->se_sess->se_node_acl;
353 tmr_tpg = tmr->task_cmd->se_sess->se_tpg;
354 if (tmr_nacl && tmr_tpg) {
355 pr_debug("LUN_RESET: TMR caller fabric: %s"
356 " initiator port %s\n",
357 tmr_tpg->se_tpg_tfo->get_fabric_name(),
358 tmr_nacl->initiatorname);
361 pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
362 (preempt_and_abort_list) ? "Preempt" : "TMR",
363 dev->transport->name, tas);
365 core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list);
366 core_tmr_drain_state_list(dev, prout_cmd, tmr_nacl, tas,
367 preempt_and_abort_list);
370 * Clear any legacy SPC-2 reservation when called during
373 if (!preempt_and_abort_list &&
374 (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)) {
375 spin_lock(&dev->dev_reservation_lock);
376 dev->dev_reserved_node_acl = NULL;
377 dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
378 spin_unlock(&dev->dev_reservation_lock);
379 pr_debug("LUN_RESET: SCSI-2 Released reservation\n");
382 atomic_long_inc(&dev->num_resets);
384 pr_debug("LUN_RESET: %s for [%s] Complete\n",
385 (preempt_and_abort_list) ? "Preempt" : "TMR",
386 dev->transport->name);