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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/version.h>
28#include <linux/slab.h>
29#include <linux/spinlock.h>
30#include <linux/list.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
44struct se_tmr_req *core_tmr_alloc_req(
45 struct se_cmd *se_cmd,
46 void *fabric_tmr_ptr,
47 u8 function)
48{
49 struct se_tmr_req *tmr;
50
51 tmr = kmem_cache_zalloc(se_tmr_req_cache, (in_interrupt()) ?
52 GFP_ATOMIC : GFP_KERNEL);
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}
64EXPORT_SYMBOL(core_tmr_alloc_req);
65
66void core_tmr_release_req(
67 struct se_tmr_req *tmr)
68{
69 struct se_device *dev = tmr->tmr_dev;
70
71 if (!dev) {
72 kmem_cache_free(se_tmr_req_cache, tmr);
73 return;
74 }
75
76 spin_lock_irq(&dev->se_tmr_lock);
77 list_del(&tmr->tmr_list);
78 spin_unlock_irq(&dev->se_tmr_lock);
79
80 kmem_cache_free(se_tmr_req_cache, tmr);
81}
82
83static void core_tmr_handle_tas_abort(
84 struct se_node_acl *tmr_nacl,
85 struct se_cmd *cmd,
86 int tas,
87 int fe_count)
88{
89 if (!fe_count) {
90 transport_cmd_finish_abort(cmd, 1);
91 return;
92 }
93 /*
94 * TASK ABORTED status (TAS) bit support
95 */
96 if ((tmr_nacl &&
97 (tmr_nacl == cmd->se_sess->se_node_acl)) || tas)
98 transport_send_task_abort(cmd);
99
100 transport_cmd_finish_abort(cmd, 0);
101}
102
103int core_tmr_lun_reset(
104 struct se_device *dev,
105 struct se_tmr_req *tmr,
106 struct list_head *preempt_and_abort_list,
107 struct se_cmd *prout_cmd)
108{
109 struct se_cmd *cmd, *tcmd;
110 struct se_node_acl *tmr_nacl = NULL;
111 struct se_portal_group *tmr_tpg = NULL;
112 struct se_queue_obj *qobj = &dev->dev_queue_obj;
113 struct se_tmr_req *tmr_p, *tmr_pp;
114 struct se_task *task, *task_tmp;
115 unsigned long flags;
116 int fe_count, tas;
117 /*
118 * TASK_ABORTED status bit, this is configurable via ConfigFS
119 * struct se_device attributes. spc4r17 section 7.4.6 Control mode page
120 *
121 * A task aborted status (TAS) bit set to zero specifies that aborted
122 * tasks shall be terminated by the device server without any response
123 * to the application client. A TAS bit set to one specifies that tasks
124 * aborted by the actions of an I_T nexus other than the I_T nexus on
125 * which the command was received shall be completed with TASK ABORTED
126 * status (see SAM-4).
127 */
128 tas = dev->se_sub_dev->se_dev_attrib.emulate_tas;
129 /*
130 * Determine if this se_tmr is coming from a $FABRIC_MOD
131 * or struct se_device passthrough..
132 */
133 if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) {
134 tmr_nacl = tmr->task_cmd->se_sess->se_node_acl;
135 tmr_tpg = tmr->task_cmd->se_sess->se_tpg;
136 if (tmr_nacl && tmr_tpg) {
137 pr_debug("LUN_RESET: TMR caller fabric: %s"
138 " initiator port %s\n",
139 tmr_tpg->se_tpg_tfo->get_fabric_name(),
140 tmr_nacl->initiatorname);
141 }
142 }
143 pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
144 (preempt_and_abort_list) ? "Preempt" : "TMR",
145 dev->transport->name, tas);
146 /*
147 * Release all pending and outgoing TMRs aside from the received
148 * LUN_RESET tmr..
149 */
150 spin_lock_irq(&dev->se_tmr_lock);
151 list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
152 /*
153 * Allow the received TMR to return with FUNCTION_COMPLETE.
154 */
155 if (tmr && (tmr_p == tmr))
156 continue;
157
158 cmd = tmr_p->task_cmd;
159 if (!cmd) {
160 pr_err("Unable to locate struct se_cmd for TMR\n");
161 continue;
162 }
163 /*
164 * If this function was called with a valid pr_res_key
165 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action
166 * skip non regisration key matching TMRs.
167 */
168 if (preempt_and_abort_list &&
169 (core_scsi3_check_cdb_abort_and_preempt(
170 preempt_and_abort_list, cmd) != 0))
171 continue;
172 spin_unlock_irq(&dev->se_tmr_lock);
173
174 spin_lock_irqsave(&cmd->t_state_lock, flags);
175 if (!atomic_read(&cmd->t_transport_active)) {
176 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
177 spin_lock_irq(&dev->se_tmr_lock);
178 continue;
179 }
180 if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
181 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
182 spin_lock_irq(&dev->se_tmr_lock);
183 continue;
184 }
185 pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
186 " Response: 0x%02x, t_state: %d\n",
187 (preempt_and_abort_list) ? "Preempt" : "", tmr_p,
188 tmr_p->function, tmr_p->response, cmd->t_state);
189 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
190
191 transport_cmd_finish_abort_tmr(cmd);
192 spin_lock_irq(&dev->se_tmr_lock);
193 }
194 spin_unlock_irq(&dev->se_tmr_lock);
195 /*
196 * Complete outstanding struct se_task CDBs with TASK_ABORTED SAM status.
197 * This is following sam4r17, section 5.6 Aborting commands, Table 38
198 * for TMR LUN_RESET:
199 *
200 * a) "Yes" indicates that each command that is aborted on an I_T nexus
201 * other than the one that caused the SCSI device condition is
202 * completed with TASK ABORTED status, if the TAS bit is set to one in
203 * the Control mode page (see SPC-4). "No" indicates that no status is
204 * returned for aborted commands.
205 *
206 * d) If the logical unit reset is caused by a particular I_T nexus
207 * (e.g., by a LOGICAL UNIT RESET task management function), then "yes"
208 * (TASK_ABORTED status) applies.
209 *
210 * Otherwise (e.g., if triggered by a hard reset), "no"
211 * (no TASK_ABORTED SAM status) applies.
212 *
213 * Note that this seems to be independent of TAS (Task Aborted Status)
214 * in the Control Mode Page.
215 */
216 spin_lock_irqsave(&dev->execute_task_lock, flags);
217 list_for_each_entry_safe(task, task_tmp, &dev->state_task_list,
218 t_state_list) {
219 if (!task->task_se_cmd) {
220 pr_err("task->task_se_cmd is NULL!\n");
221 continue;
222 }
223 cmd = task->task_se_cmd;
224
225 /*
226 * For PREEMPT_AND_ABORT usage, only process commands
227 * with a matching reservation key.
228 */
229 if (preempt_and_abort_list &&
230 (core_scsi3_check_cdb_abort_and_preempt(
231 preempt_and_abort_list, cmd) != 0))
232 continue;
233 /*
234 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
235 */
236 if (prout_cmd == cmd)
237 continue;
238
239 list_del(&task->t_state_list);
240 atomic_set(&task->task_state_active, 0);
241 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
242
243 spin_lock_irqsave(&cmd->t_state_lock, flags);
244 pr_debug("LUN_RESET: %s cmd: %p task: %p"
245 " ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state/"
246 "def_t_state: %d/%d cdb: 0x%02x\n",
247 (preempt_and_abort_list) ? "Preempt" : "", cmd, task,
248 cmd->se_tfo->get_task_tag(cmd), 0,
249 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
250 cmd->deferred_t_state, cmd->t_task_cdb[0]);
251 pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx"
252 " t_task_cdbs: %d t_task_cdbs_left: %d"
253 " t_task_cdbs_sent: %d -- t_transport_active: %d"
254 " t_transport_stop: %d t_transport_sent: %d\n",
255 cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key,
256 cmd->t_task_list_num,
257 atomic_read(&cmd->t_task_cdbs_left),
258 atomic_read(&cmd->t_task_cdbs_sent),
259 atomic_read(&cmd->t_transport_active),
260 atomic_read(&cmd->t_transport_stop),
261 atomic_read(&cmd->t_transport_sent));
262
263 if (atomic_read(&task->task_active)) {
264 atomic_set(&task->task_stop, 1);
265 spin_unlock_irqrestore(
266 &cmd->t_state_lock, flags);
267
268 pr_debug("LUN_RESET: Waiting for task: %p to shutdown"
269 " for dev: %p\n", task, dev);
270 wait_for_completion(&task->task_stop_comp);
271 pr_debug("LUN_RESET Completed task: %p shutdown for"
272 " dev: %p\n", task, dev);
273 spin_lock_irqsave(&cmd->t_state_lock, flags);
274 atomic_dec(&cmd->t_task_cdbs_left);
275
276 atomic_set(&task->task_active, 0);
277 atomic_set(&task->task_stop, 0);
278 } else {
279 if (atomic_read(&task->task_execute_queue) != 0)
280 transport_remove_task_from_execute_queue(task, dev);
281 }
282 __transport_stop_task_timer(task, &flags);
283
284 if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
285 spin_unlock_irqrestore(
286 &cmd->t_state_lock, flags);
287 pr_debug("LUN_RESET: Skipping task: %p, dev: %p for"
288 " t_task_cdbs_ex_left: %d\n", task, dev,
289 atomic_read(&cmd->t_task_cdbs_ex_left));
290
291 spin_lock_irqsave(&dev->execute_task_lock, flags);
292 continue;
293 }
294 fe_count = atomic_read(&cmd->t_fe_count);
295
296 if (atomic_read(&cmd->t_transport_active)) {
297 pr_debug("LUN_RESET: got t_transport_active = 1 for"
298 " task: %p, t_fe_count: %d dev: %p\n", task,
299 fe_count, dev);
300 atomic_set(&cmd->t_transport_aborted, 1);
301 spin_unlock_irqrestore(&cmd->t_state_lock,
302 flags);
303 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
304
305 spin_lock_irqsave(&dev->execute_task_lock, flags);
306 continue;
307 }
308 pr_debug("LUN_RESET: Got t_transport_active = 0 for task: %p,"
309 " t_fe_count: %d dev: %p\n", task, fe_count, dev);
310 atomic_set(&cmd->t_transport_aborted, 1);
311 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
312 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
313
314 spin_lock_irqsave(&dev->execute_task_lock, flags);
315 }
316 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
317 /*
318 * Release all commands remaining in the struct se_device cmd queue.
319 *
320 * This follows the same logic as above for the struct se_device
321 * struct se_task state list, where commands are returned with
322 * TASK_ABORTED status, if there is an outstanding $FABRIC_MOD
323 * reference, otherwise the struct se_cmd is released.
324 */
325 spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
326 list_for_each_entry_safe(cmd, tcmd, &qobj->qobj_list, se_queue_node) {
327 /*
328 * For PREEMPT_AND_ABORT usage, only process commands
329 * with a matching reservation key.
330 */
331 if (preempt_and_abort_list &&
332 (core_scsi3_check_cdb_abort_and_preempt(
333 preempt_and_abort_list, cmd) != 0))
334 continue;
335 /*
336 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
337 */
338 if (prout_cmd == cmd)
339 continue;
340
341 atomic_dec(&cmd->t_transport_queue_active);
342 atomic_dec(&qobj->queue_cnt);
343 list_del(&cmd->se_queue_node);
344 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
345
346 pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:"
347 " %d t_fe_count: %d\n", (preempt_and_abort_list) ?
348 "Preempt" : "", cmd, cmd->t_state,
349 atomic_read(&cmd->t_fe_count));
350 /*
351 * Signal that the command has failed via cmd->se_cmd_flags,
352 */
353 transport_new_cmd_failure(cmd);
354
355 core_tmr_handle_tas_abort(tmr_nacl, cmd, tas,
356 atomic_read(&cmd->t_fe_count));
357 spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
358 }
359 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
360 /*
361 * Clear any legacy SPC-2 reservation when called during
362 * LOGICAL UNIT RESET
363 */
364 if (!preempt_and_abort_list &&
365 (dev->dev_flags & DF_SPC2_RESERVATIONS)) {
366 spin_lock(&dev->dev_reservation_lock);
367 dev->dev_reserved_node_acl = NULL;
368 dev->dev_flags &= ~DF_SPC2_RESERVATIONS;
369 spin_unlock(&dev->dev_reservation_lock);
370 pr_debug("LUN_RESET: SCSI-2 Released reservation\n");
371 }
372
373 spin_lock_irq(&dev->stats_lock);
374 dev->num_resets++;
375 spin_unlock_irq(&dev->stats_lock);
376
377 pr_debug("LUN_RESET: %s for [%s] Complete\n",
378 (preempt_and_abort_list) ? "Preempt" : "TMR",
379 dev->transport->name);
380 return 0;
381}
1/*******************************************************************************
2 * Filename: target_core_tmr.c
3 *
4 * This file contains SPC-3 task management infrastructure
5 *
6 * (c) Copyright 2009-2013 Datera, Inc.
7 *
8 * Nicholas A. Bellinger <nab@kernel.org>
9 *
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.
14 *
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.
19 *
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.
23 *
24 ******************************************************************************/
25
26#include <linux/slab.h>
27#include <linux/spinlock.h>
28#include <linux/list.h>
29#include <linux/export.h>
30
31#include <target/target_core_base.h>
32#include <target/target_core_backend.h>
33#include <target/target_core_fabric.h>
34
35#include "target_core_internal.h"
36#include "target_core_alua.h"
37#include "target_core_pr.h"
38
39int core_tmr_alloc_req(
40 struct se_cmd *se_cmd,
41 void *fabric_tmr_ptr,
42 u8 function,
43 gfp_t gfp_flags)
44{
45 struct se_tmr_req *tmr;
46
47 tmr = kzalloc(sizeof(struct se_tmr_req), gfp_flags);
48 if (!tmr) {
49 pr_err("Unable to allocate struct se_tmr_req\n");
50 return -ENOMEM;
51 }
52
53 se_cmd->se_cmd_flags |= SCF_SCSI_TMR_CDB;
54 se_cmd->se_tmr_req = tmr;
55 tmr->task_cmd = se_cmd;
56 tmr->fabric_tmr_ptr = fabric_tmr_ptr;
57 tmr->function = function;
58 INIT_LIST_HEAD(&tmr->tmr_list);
59
60 return 0;
61}
62EXPORT_SYMBOL(core_tmr_alloc_req);
63
64void core_tmr_release_req(struct se_tmr_req *tmr)
65{
66 struct se_device *dev = tmr->tmr_dev;
67 unsigned long flags;
68
69 if (dev) {
70 spin_lock_irqsave(&dev->se_tmr_lock, flags);
71 list_del_init(&tmr->tmr_list);
72 spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
73 }
74
75 kfree(tmr);
76}
77
78static int core_tmr_handle_tas_abort(struct se_cmd *cmd, int tas)
79{
80 unsigned long flags;
81 bool remove = true, send_tas;
82 /*
83 * TASK ABORTED status (TAS) bit support
84 */
85 spin_lock_irqsave(&cmd->t_state_lock, flags);
86 send_tas = (cmd->transport_state & CMD_T_TAS);
87 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
88
89 if (send_tas) {
90 remove = false;
91 transport_send_task_abort(cmd);
92 }
93
94 return transport_cmd_finish_abort(cmd, remove);
95}
96
97static int target_check_cdb_and_preempt(struct list_head *list,
98 struct se_cmd *cmd)
99{
100 struct t10_pr_registration *reg;
101
102 if (!list)
103 return 0;
104 list_for_each_entry(reg, list, pr_reg_abort_list) {
105 if (reg->pr_res_key == cmd->pr_res_key)
106 return 0;
107 }
108
109 return 1;
110}
111
112static bool __target_check_io_state(struct se_cmd *se_cmd,
113 struct se_session *tmr_sess, int tas)
114{
115 struct se_session *sess = se_cmd->se_sess;
116
117 assert_spin_locked(&sess->sess_cmd_lock);
118 WARN_ON_ONCE(!irqs_disabled());
119 /*
120 * If command already reached CMD_T_COMPLETE state within
121 * target_complete_cmd() or CMD_T_FABRIC_STOP due to shutdown,
122 * this se_cmd has been passed to fabric driver and will
123 * not be aborted.
124 *
125 * Otherwise, obtain a local se_cmd->cmd_kref now for TMR
126 * ABORT_TASK + LUN_RESET for CMD_T_ABORTED processing as
127 * long as se_cmd->cmd_kref is still active unless zero.
128 */
129 spin_lock(&se_cmd->t_state_lock);
130 if (se_cmd->transport_state & (CMD_T_COMPLETE | CMD_T_FABRIC_STOP)) {
131 pr_debug("Attempted to abort io tag: %llu already complete or"
132 " fabric stop, skipping\n", se_cmd->tag);
133 spin_unlock(&se_cmd->t_state_lock);
134 return false;
135 }
136 if (se_cmd->transport_state & CMD_T_PRE_EXECUTE) {
137 if (se_cmd->scsi_status) {
138 pr_debug("Attempted to abort io tag: %llu early failure"
139 " status: 0x%02x\n", se_cmd->tag,
140 se_cmd->scsi_status);
141 spin_unlock(&se_cmd->t_state_lock);
142 return false;
143 }
144 }
145 if (sess->sess_tearing_down || se_cmd->cmd_wait_set) {
146 pr_debug("Attempted to abort io tag: %llu already shutdown,"
147 " skipping\n", se_cmd->tag);
148 spin_unlock(&se_cmd->t_state_lock);
149 return false;
150 }
151 se_cmd->transport_state |= CMD_T_ABORTED;
152
153 if ((tmr_sess != se_cmd->se_sess) && tas)
154 se_cmd->transport_state |= CMD_T_TAS;
155
156 spin_unlock(&se_cmd->t_state_lock);
157
158 return kref_get_unless_zero(&se_cmd->cmd_kref);
159}
160
161void core_tmr_abort_task(
162 struct se_device *dev,
163 struct se_tmr_req *tmr,
164 struct se_session *se_sess)
165{
166 struct se_cmd *se_cmd;
167 unsigned long flags;
168 u64 ref_tag;
169
170 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
171 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
172
173 if (dev != se_cmd->se_dev)
174 continue;
175
176 /* skip task management functions, including tmr->task_cmd */
177 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
178 continue;
179
180 ref_tag = se_cmd->tag;
181 if (tmr->ref_task_tag != ref_tag)
182 continue;
183
184 printk("ABORT_TASK: Found referenced %s task_tag: %llu\n",
185 se_cmd->se_tfo->get_fabric_name(), ref_tag);
186
187 if (!__target_check_io_state(se_cmd, se_sess, 0))
188 continue;
189
190 list_del_init(&se_cmd->se_cmd_list);
191 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
192
193 cancel_work_sync(&se_cmd->work);
194 transport_wait_for_tasks(se_cmd);
195
196 if (!transport_cmd_finish_abort(se_cmd, true))
197 target_put_sess_cmd(se_cmd);
198
199 printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for"
200 " ref_tag: %llu\n", ref_tag);
201 tmr->response = TMR_FUNCTION_COMPLETE;
202 atomic_long_inc(&dev->aborts_complete);
203 return;
204 }
205 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
206
207 printk("ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST for ref_tag: %lld\n",
208 tmr->ref_task_tag);
209 tmr->response = TMR_TASK_DOES_NOT_EXIST;
210 atomic_long_inc(&dev->aborts_no_task);
211}
212
213static void core_tmr_drain_tmr_list(
214 struct se_device *dev,
215 struct se_tmr_req *tmr,
216 struct list_head *preempt_and_abort_list)
217{
218 LIST_HEAD(drain_tmr_list);
219 struct se_session *sess;
220 struct se_tmr_req *tmr_p, *tmr_pp;
221 struct se_cmd *cmd;
222 unsigned long flags;
223 bool rc;
224 /*
225 * Release all pending and outgoing TMRs aside from the received
226 * LUN_RESET tmr..
227 */
228 spin_lock_irqsave(&dev->se_tmr_lock, flags);
229 if (tmr)
230 list_del_init(&tmr->tmr_list);
231 list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
232 cmd = tmr_p->task_cmd;
233 if (!cmd) {
234 pr_err("Unable to locate struct se_cmd for TMR\n");
235 continue;
236 }
237 /*
238 * If this function was called with a valid pr_res_key
239 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action
240 * skip non registration key matching TMRs.
241 */
242 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
243 continue;
244
245 sess = cmd->se_sess;
246 if (WARN_ON_ONCE(!sess))
247 continue;
248
249 spin_lock(&sess->sess_cmd_lock);
250 spin_lock(&cmd->t_state_lock);
251 if (!(cmd->transport_state & CMD_T_ACTIVE) ||
252 (cmd->transport_state & CMD_T_FABRIC_STOP)) {
253 spin_unlock(&cmd->t_state_lock);
254 spin_unlock(&sess->sess_cmd_lock);
255 continue;
256 }
257 if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
258 spin_unlock(&cmd->t_state_lock);
259 spin_unlock(&sess->sess_cmd_lock);
260 continue;
261 }
262 if (sess->sess_tearing_down || cmd->cmd_wait_set) {
263 spin_unlock(&cmd->t_state_lock);
264 spin_unlock(&sess->sess_cmd_lock);
265 continue;
266 }
267 cmd->transport_state |= CMD_T_ABORTED;
268 spin_unlock(&cmd->t_state_lock);
269
270 rc = kref_get_unless_zero(&cmd->cmd_kref);
271 if (!rc) {
272 printk("LUN_RESET TMR: non-zero kref_get_unless_zero\n");
273 spin_unlock(&sess->sess_cmd_lock);
274 continue;
275 }
276 spin_unlock(&sess->sess_cmd_lock);
277
278 list_move_tail(&tmr_p->tmr_list, &drain_tmr_list);
279 }
280 spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
281
282 list_for_each_entry_safe(tmr_p, tmr_pp, &drain_tmr_list, tmr_list) {
283 list_del_init(&tmr_p->tmr_list);
284 cmd = tmr_p->task_cmd;
285
286 pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
287 " Response: 0x%02x, t_state: %d\n",
288 (preempt_and_abort_list) ? "Preempt" : "", tmr_p,
289 tmr_p->function, tmr_p->response, cmd->t_state);
290
291 cancel_work_sync(&cmd->work);
292 transport_wait_for_tasks(cmd);
293
294 if (!transport_cmd_finish_abort(cmd, 1))
295 target_put_sess_cmd(cmd);
296 }
297}
298
299static void core_tmr_drain_state_list(
300 struct se_device *dev,
301 struct se_cmd *prout_cmd,
302 struct se_session *tmr_sess,
303 int tas,
304 struct list_head *preempt_and_abort_list)
305{
306 LIST_HEAD(drain_task_list);
307 struct se_session *sess;
308 struct se_cmd *cmd, *next;
309 unsigned long flags;
310 int rc;
311
312 /*
313 * Complete outstanding commands with TASK_ABORTED SAM status.
314 *
315 * This is following sam4r17, section 5.6 Aborting commands, Table 38
316 * for TMR LUN_RESET:
317 *
318 * a) "Yes" indicates that each command that is aborted on an I_T nexus
319 * other than the one that caused the SCSI device condition is
320 * completed with TASK ABORTED status, if the TAS bit is set to one in
321 * the Control mode page (see SPC-4). "No" indicates that no status is
322 * returned for aborted commands.
323 *
324 * d) If the logical unit reset is caused by a particular I_T nexus
325 * (e.g., by a LOGICAL UNIT RESET task management function), then "yes"
326 * (TASK_ABORTED status) applies.
327 *
328 * Otherwise (e.g., if triggered by a hard reset), "no"
329 * (no TASK_ABORTED SAM status) applies.
330 *
331 * Note that this seems to be independent of TAS (Task Aborted Status)
332 * in the Control Mode Page.
333 */
334 spin_lock_irqsave(&dev->execute_task_lock, flags);
335 list_for_each_entry_safe(cmd, next, &dev->state_list, state_list) {
336 /*
337 * For PREEMPT_AND_ABORT usage, only process commands
338 * with a matching reservation key.
339 */
340 if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
341 continue;
342
343 /*
344 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
345 */
346 if (prout_cmd == cmd)
347 continue;
348
349 sess = cmd->se_sess;
350 if (WARN_ON_ONCE(!sess))
351 continue;
352
353 spin_lock(&sess->sess_cmd_lock);
354 rc = __target_check_io_state(cmd, tmr_sess, tas);
355 spin_unlock(&sess->sess_cmd_lock);
356 if (!rc)
357 continue;
358
359 list_move_tail(&cmd->state_list, &drain_task_list);
360 cmd->state_active = false;
361 }
362 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
363
364 while (!list_empty(&drain_task_list)) {
365 cmd = list_entry(drain_task_list.next, struct se_cmd, state_list);
366 list_del_init(&cmd->state_list);
367
368 target_show_cmd("LUN_RESET: ", cmd);
369 pr_debug("LUN_RESET: ITT[0x%08llx] - %s pr_res_key: 0x%016Lx\n",
370 cmd->tag, (preempt_and_abort_list) ? "preempt" : "",
371 cmd->pr_res_key);
372
373 /*
374 * If the command may be queued onto a workqueue cancel it now.
375 *
376 * This is equivalent to removal from the execute queue in the
377 * loop above, but we do it down here given that
378 * cancel_work_sync may block.
379 */
380 cancel_work_sync(&cmd->work);
381 transport_wait_for_tasks(cmd);
382
383 if (!core_tmr_handle_tas_abort(cmd, tas))
384 target_put_sess_cmd(cmd);
385 }
386}
387
388int core_tmr_lun_reset(
389 struct se_device *dev,
390 struct se_tmr_req *tmr,
391 struct list_head *preempt_and_abort_list,
392 struct se_cmd *prout_cmd)
393{
394 struct se_node_acl *tmr_nacl = NULL;
395 struct se_portal_group *tmr_tpg = NULL;
396 struct se_session *tmr_sess = NULL;
397 int tas;
398 /*
399 * TASK_ABORTED status bit, this is configurable via ConfigFS
400 * struct se_device attributes. spc4r17 section 7.4.6 Control mode page
401 *
402 * A task aborted status (TAS) bit set to zero specifies that aborted
403 * tasks shall be terminated by the device server without any response
404 * to the application client. A TAS bit set to one specifies that tasks
405 * aborted by the actions of an I_T nexus other than the I_T nexus on
406 * which the command was received shall be completed with TASK ABORTED
407 * status (see SAM-4).
408 */
409 tas = dev->dev_attrib.emulate_tas;
410 /*
411 * Determine if this se_tmr is coming from a $FABRIC_MOD
412 * or struct se_device passthrough..
413 */
414 if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) {
415 tmr_sess = tmr->task_cmd->se_sess;
416 tmr_nacl = tmr_sess->se_node_acl;
417 tmr_tpg = tmr_sess->se_tpg;
418 if (tmr_nacl && tmr_tpg) {
419 pr_debug("LUN_RESET: TMR caller fabric: %s"
420 " initiator port %s\n",
421 tmr_tpg->se_tpg_tfo->get_fabric_name(),
422 tmr_nacl->initiatorname);
423 }
424 }
425 pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
426 (preempt_and_abort_list) ? "Preempt" : "TMR",
427 dev->transport->name, tas);
428
429 core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list);
430 core_tmr_drain_state_list(dev, prout_cmd, tmr_sess, tas,
431 preempt_and_abort_list);
432
433 /*
434 * Clear any legacy SPC-2 reservation when called during
435 * LOGICAL UNIT RESET
436 */
437 if (!preempt_and_abort_list &&
438 (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)) {
439 spin_lock(&dev->dev_reservation_lock);
440 dev->dev_reserved_node_acl = NULL;
441 dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
442 spin_unlock(&dev->dev_reservation_lock);
443 pr_debug("LUN_RESET: SCSI-2 Released reservation\n");
444 }
445
446 atomic_long_inc(&dev->num_resets);
447
448 pr_debug("LUN_RESET: %s for [%s] Complete\n",
449 (preempt_and_abort_list) ? "Preempt" : "TMR",
450 dev->transport->name);
451 return 0;
452}
453