[mirror_ubuntu-bionic-kernel.git] / drivers / target / target_core_tmr.c

/*******************************************************************************
 * Filename:  target_core_tmr.c
 *
 * This file contains SPC-3 task management infrastructure
 *
 * Copyright (c) 2009,2010 Rising Tide Systems
 * Copyright (c) 2009,2010 Linux-iSCSI.org
 *
 * Nicholas A. Bellinger <nab@kernel.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 ******************************************************************************/

#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/export.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>

#include <target/target_core_base.h>
#include <target/target_core_device.h>
#include <target/target_core_tmr.h>
#include <target/target_core_transport.h>
#include <target/target_core_fabric_ops.h>
#include <target/target_core_configfs.h>

#include "target_core_alua.h"
#include "target_core_pr.h"

struct se_tmr_req *core_tmr_alloc_req(
	struct se_cmd *se_cmd,
	void *fabric_tmr_ptr,
	u8 function,
	gfp_t gfp_flags)
{
	struct se_tmr_req *tmr;

	tmr = kmem_cache_zalloc(se_tmr_req_cache, gfp_flags);
	if (!tmr) {
		pr_err("Unable to allocate struct se_tmr_req\n");
		return ERR_PTR(-ENOMEM);
	}
	tmr->task_cmd = se_cmd;
	tmr->fabric_tmr_ptr = fabric_tmr_ptr;
	tmr->function = function;
	INIT_LIST_HEAD(&tmr->tmr_list);

	return tmr;
}
EXPORT_SYMBOL(core_tmr_alloc_req);

void core_tmr_release_req(
	struct se_tmr_req *tmr)
{
	struct se_device *dev = tmr->tmr_dev;
	unsigned long flags;

	if (!dev) {
		kmem_cache_free(se_tmr_req_cache, tmr);
		return;
	}

	spin_lock_irqsave(&dev->se_tmr_lock, flags);
	list_del(&tmr->tmr_list);
	spin_unlock_irqrestore(&dev->se_tmr_lock, flags);

	kmem_cache_free(se_tmr_req_cache, tmr);
}

static void core_tmr_handle_tas_abort(
	struct se_node_acl *tmr_nacl,
	struct se_cmd *cmd,
	int tas,
	int fe_count)
{
	if (!fe_count) {
		transport_cmd_finish_abort(cmd, 1);
		return;
	}
	/*
	 * TASK ABORTED status (TAS) bit support
	*/
	if ((tmr_nacl &&
	     (tmr_nacl == cmd->se_sess->se_node_acl)) || tas)
		transport_send_task_abort(cmd);

	transport_cmd_finish_abort(cmd, 0);
}

static void core_tmr_drain_tmr_list(
	struct se_device *dev,
	struct se_tmr_req *tmr,
	struct list_head *preempt_and_abort_list)
{
	LIST_HEAD(drain_tmr_list);
	struct se_tmr_req *tmr_p, *tmr_pp;
	struct se_cmd *cmd;
	unsigned long flags;
	/*
	 * Release all pending and outgoing TMRs aside from the received
	 * LUN_RESET tmr..
	 */
	spin_lock_irqsave(&dev->se_tmr_lock, flags);
	list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
		/*
		 * Allow the received TMR to return with FUNCTION_COMPLETE.
		 */
		if (tmr_p == tmr)
			continue;

		cmd = tmr_p->task_cmd;
		if (!cmd) {
			pr_err("Unable to locate struct se_cmd for TMR\n");
			continue;
		}
		/*
		 * If this function was called with a valid pr_res_key
		 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action
		 * skip non regisration key matching TMRs.
		 */
		if (preempt_and_abort_list &&
		    (core_scsi3_check_cdb_abort_and_preempt(
					preempt_and_abort_list, cmd) != 0))
			continue;

		spin_lock(&cmd->t_state_lock);
		if (!atomic_read(&cmd->t_transport_active)) {
			spin_unlock(&cmd->t_state_lock);
			continue;
		}
		if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
			spin_unlock(&cmd->t_state_lock);
			continue;
		}
		spin_unlock(&cmd->t_state_lock);

		list_move_tail(&tmr_p->tmr_list, &drain_tmr_list);
	}
	spin_unlock_irqrestore(&dev->se_tmr_lock, flags);

	list_for_each_entry_safe(tmr_p, tmr_pp, &drain_tmr_list, tmr_list) {
		list_del_init(&tmr_p->tmr_list);
		cmd = tmr_p->task_cmd;

		pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
			" Response: 0x%02x, t_state: %d\n",
			(preempt_and_abort_list) ? "Preempt" : "", tmr_p,
			tmr_p->function, tmr_p->response, cmd->t_state);

		transport_cmd_finish_abort(cmd, 1);
	}
}

static void core_tmr_drain_task_list(
	struct se_device *dev,
	struct se_cmd *prout_cmd,
	struct se_node_acl *tmr_nacl,
	int tas,
	struct list_head *preempt_and_abort_list)
{
	LIST_HEAD(drain_task_list);
	struct se_cmd *cmd;
	struct se_task *task, *task_tmp;
	unsigned long flags;
	int fe_count;
	/*
	 * Complete outstanding struct se_task CDBs with TASK_ABORTED SAM status.
	 * This is following sam4r17, section 5.6 Aborting commands, Table 38
	 * for TMR LUN_RESET:
	 *
	 * a) "Yes" indicates that each command that is aborted on an I_T nexus
	 * other than the one that caused the SCSI device condition is
	 * completed with TASK ABORTED status, if the TAS bit is set to one in
	 * the Control mode page (see SPC-4). "No" indicates that no status is
	 * returned for aborted commands.
	 *
	 * d) If the logical unit reset is caused by a particular I_T nexus
	 * (e.g., by a LOGICAL UNIT RESET task management function), then "yes"
	 * (TASK_ABORTED status) applies.
	 *
	 * Otherwise (e.g., if triggered by a hard reset), "no"
	 * (no TASK_ABORTED SAM status) applies.
	 *
	 * Note that this seems to be independent of TAS (Task Aborted Status)
	 * in the Control Mode Page.
	 */
	spin_lock_irqsave(&dev->execute_task_lock, flags);
	list_for_each_entry_safe(task, task_tmp, &dev->state_task_list,
				t_state_list) {
		if (!task->task_se_cmd) {
			pr_err("task->task_se_cmd is NULL!\n");
			continue;
		}
		cmd = task->task_se_cmd;

		/*
		 * For PREEMPT_AND_ABORT usage, only process commands
		 * with a matching reservation key.
		 */
		if (preempt_and_abort_list &&
		    (core_scsi3_check_cdb_abort_and_preempt(
					preempt_and_abort_list, cmd) != 0))
			continue;
		/*
		 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
		 */
		if (prout_cmd == cmd)
			continue;

		list_move_tail(&task->t_state_list, &drain_task_list);
		atomic_set(&task->task_state_active, 0);
		/*
		 * Remove from task execute list before processing drain_task_list
		 */
		if (!list_empty(&task->t_execute_list))
			__transport_remove_task_from_execute_queue(task, dev);
	}
	spin_unlock_irqrestore(&dev->execute_task_lock, flags);

	while (!list_empty(&drain_task_list)) {
		task = list_entry(drain_task_list.next, struct se_task, t_state_list);
		list_del(&task->t_state_list);
		cmd = task->task_se_cmd;

		pr_debug("LUN_RESET: %s cmd: %p task: %p"
			" ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state: %d"
			"cdb: 0x%02x\n",
			(preempt_and_abort_list) ? "Preempt" : "", cmd, task,
			cmd->se_tfo->get_task_tag(cmd), 0,
			cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
			cmd->t_task_cdb[0]);
		pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx"
			" t_task_cdbs: %d t_task_cdbs_left: %d"
			" t_task_cdbs_sent: %d -- t_transport_active: %d"
			" t_transport_stop: %d t_transport_sent: %d\n",
			cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key,
			cmd->t_task_list_num,
			atomic_read(&cmd->t_task_cdbs_left),
			atomic_read(&cmd->t_task_cdbs_sent),
			atomic_read(&cmd->t_transport_active),
			atomic_read(&cmd->t_transport_stop),
			atomic_read(&cmd->t_transport_sent));

		/*
		 * If the command may be queued onto a workqueue cancel it now.
		 *
		 * This is equivalent to removal from the execute queue in the
		 * loop above, but we do it down here given that
		 * cancel_work_sync may block.
		 */
		if (cmd->t_state == TRANSPORT_COMPLETE)
			cancel_work_sync(&cmd->work);

		spin_lock_irqsave(&cmd->t_state_lock, flags);
		target_stop_task(task, &flags);

		if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
			spin_unlock_irqrestore(&cmd->t_state_lock, flags);
			pr_debug("LUN_RESET: Skipping task: %p, dev: %p for"
				" t_task_cdbs_ex_left: %d\n", task, dev,
				atomic_read(&cmd->t_task_cdbs_ex_left));
			continue;
		}
		fe_count = atomic_read(&cmd->t_fe_count);

		if (atomic_read(&cmd->t_transport_active)) {
			pr_debug("LUN_RESET: got t_transport_active = 1 for"
				" task: %p, t_fe_count: %d dev: %p\n", task,
				fe_count, dev);
			atomic_set(&cmd->t_transport_aborted, 1);
			spin_unlock_irqrestore(&cmd->t_state_lock, flags);

			core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
			continue;
		}
		pr_debug("LUN_RESET: Got t_transport_active = 0 for task: %p,"
			" t_fe_count: %d dev: %p\n", task, fe_count, dev);
		atomic_set(&cmd->t_transport_aborted, 1);
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);

		core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
	}
}

static void core_tmr_drain_cmd_list(
	struct se_device *dev,
	struct se_cmd *prout_cmd,
	struct se_node_acl *tmr_nacl,
	int tas,
	struct list_head *preempt_and_abort_list)
{
	LIST_HEAD(drain_cmd_list);
	struct se_queue_obj *qobj = &dev->dev_queue_obj;
	struct se_cmd *cmd, *tcmd;
	unsigned long flags;
	/*
	 * Release all commands remaining in the struct se_device cmd queue.
	 *
	 * This follows the same logic as above for the struct se_device
	 * struct se_task state list, where commands are returned with
	 * TASK_ABORTED status, if there is an outstanding $FABRIC_MOD
	 * reference, otherwise the struct se_cmd is released.
	 */
	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
	list_for_each_entry_safe(cmd, tcmd, &qobj->qobj_list, se_queue_node) {
		/*
		 * For PREEMPT_AND_ABORT usage, only process commands
		 * with a matching reservation key.
		 */
		if (preempt_and_abort_list &&
		    (core_scsi3_check_cdb_abort_and_preempt(
					preempt_and_abort_list, cmd) != 0))
			continue;
		/*
		 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
		 */
		if (prout_cmd == cmd)
			continue;

		atomic_set(&cmd->t_transport_queue_active, 0);
		atomic_dec(&qobj->queue_cnt);
		list_move_tail(&cmd->se_queue_node, &drain_cmd_list);
	}
	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);

	while (!list_empty(&drain_cmd_list)) {
		cmd = list_entry(drain_cmd_list.next, struct se_cmd, se_queue_node);
		list_del_init(&cmd->se_queue_node);

		pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:"
			" %d t_fe_count: %d\n", (preempt_and_abort_list) ?
			"Preempt" : "", cmd, cmd->t_state,
			atomic_read(&cmd->t_fe_count));

		core_tmr_handle_tas_abort(tmr_nacl, cmd, tas,
				atomic_read(&cmd->t_fe_count));
	}
}

int core_tmr_lun_reset(
        struct se_device *dev,
        struct se_tmr_req *tmr,
        struct list_head *preempt_and_abort_list,
        struct se_cmd *prout_cmd)
{
	struct se_node_acl *tmr_nacl = NULL;
	struct se_portal_group *tmr_tpg = NULL;
	int tas;
        /*
	 * TASK_ABORTED status bit, this is configurable via ConfigFS
	 * struct se_device attributes.  spc4r17 section 7.4.6 Control mode page
	 *
	 * A task aborted status (TAS) bit set to zero specifies that aborted
	 * tasks shall be terminated by the device server without any response
	 * to the application client. A TAS bit set to one specifies that tasks
	 * aborted by the actions of an I_T nexus other than the I_T nexus on
	 * which the command was received shall be completed with TASK ABORTED
	 * status (see SAM-4).
	 */
	tas = dev->se_sub_dev->se_dev_attrib.emulate_tas;
	/*
	 * Determine if this se_tmr is coming from a $FABRIC_MOD
	 * or struct se_device passthrough..
	 */
	if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) {
		tmr_nacl = tmr->task_cmd->se_sess->se_node_acl;
		tmr_tpg = tmr->task_cmd->se_sess->se_tpg;
		if (tmr_nacl && tmr_tpg) {
			pr_debug("LUN_RESET: TMR caller fabric: %s"
				" initiator port %s\n",
				tmr_tpg->se_tpg_tfo->get_fabric_name(),
				tmr_nacl->initiatorname);
		}
	}
	pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
		(preempt_and_abort_list) ? "Preempt" : "TMR",
		dev->transport->name, tas);

	core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list);
	core_tmr_drain_task_list(dev, prout_cmd, tmr_nacl, tas,
				preempt_and_abort_list);
	core_tmr_drain_cmd_list(dev, prout_cmd, tmr_nacl, tas,
				preempt_and_abort_list);
	/*
	 * Clear any legacy SPC-2 reservation when called during
	 * LOGICAL UNIT RESET
	 */
	if (!preempt_and_abort_list &&
	     (dev->dev_flags & DF_SPC2_RESERVATIONS)) {
		spin_lock(&dev->dev_reservation_lock);
		dev->dev_reserved_node_acl = NULL;
		dev->dev_flags &= ~DF_SPC2_RESERVATIONS;
		spin_unlock(&dev->dev_reservation_lock);
		pr_debug("LUN_RESET: SCSI-2 Released reservation\n");
	}

	spin_lock_irq(&dev->stats_lock);
	dev->num_resets++;
	spin_unlock_irq(&dev->stats_lock);

	pr_debug("LUN_RESET: %s for [%s] Complete\n",
			(preempt_and_abort_list) ? "Preempt" : "TMR",
			dev->transport->name);
	return 0;
}
Commit	Line	Data
c66ac9db NB	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
c66ac9db NB	27	#include <linux/slab.h>
	28	#include <linux/spinlock.h>
	29	#include <linux/list.h>
c53181af	30	#include <linux/export.h>
c66ac9db NB	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
c66ac9db NB	44	struct se_tmr_req *core_tmr_alloc_req(
	45	struct se_cmd *se_cmd,
	46	void *fabric_tmr_ptr,
dd503a5f RD	47	u8 function,
dd503a5f RD	48	gfp_t gfp_flags)
c66ac9db NB	49	{
	50	struct se_tmr_req *tmr;
	51
dd503a5f	52	tmr = kmem_cache_zalloc(se_tmr_req_cache, gfp_flags);
6708bb27 AG	53	if (!tmr) {
6708bb27 AG	54	pr_err("Unable to allocate struct se_tmr_req\n");
c66ac9db NB	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;
d050ffb9	70	unsigned long flags;
c66ac9db	71
7fd29aa9 NB	72	if (!dev) {
	73	kmem_cache_free(se_tmr_req_cache, tmr);
	74	return;
	75	}
	76
d050ffb9	77	spin_lock_irqsave(&dev->se_tmr_lock, flags);
c66ac9db	78	list_del(&tmr->tmr_list);
d050ffb9	79	spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
7fd29aa9 NB	80
7fd29aa9 NB	81	kmem_cache_free(se_tmr_req_cache, tmr);
c66ac9db NB	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	{
6708bb27	90	if (!fe_count) {
c66ac9db NB	91	transport_cmd_finish_abort(cmd, 1);
	92	return;
	93	}
	94	/*
	95	* TASK ABORTED status (TAS) bit support
	96	*/
6708bb27	97	if ((tmr_nacl &&
c66ac9db NB	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
d050ffb9	104	static void core_tmr_drain_tmr_list(
c66ac9db NB	105	struct se_device *dev,
c66ac9db NB	106	struct se_tmr_req *tmr,
d050ffb9	107	struct list_head *preempt_and_abort_list)
c66ac9db	108	{
d050ffb9	109	LIST_HEAD(drain_tmr_list);
c66ac9db	110	struct se_tmr_req tmr_p, tmr_pp;
d050ffb9	111	struct se_cmd *cmd;
c66ac9db	112	unsigned long flags;
c66ac9db NB	113	/*
	114	* Release all pending and outgoing TMRs aside from the received
	115	* LUN_RESET tmr..
	116	*/
d050ffb9	117	spin_lock_irqsave(&dev->se_tmr_lock, flags);
c66ac9db NB	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	*/
abc1fd4f	122	if (tmr_p == tmr)
c66ac9db NB	123	continue;
	124
	125	cmd = tmr_p->task_cmd;
6708bb27 AG	126	if (!cmd) {
6708bb27 AG	127	pr_err("Unable to locate struct se_cmd for TMR\n");
c66ac9db NB	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	*/
6708bb27	135	if (preempt_and_abort_list &&
c66ac9db NB	136	(core_scsi3_check_cdb_abort_and_preempt(
	137	preempt_and_abort_list, cmd) != 0))
	138	continue;
c66ac9db	139
d050ffb9	140	spin_lock(&cmd->t_state_lock);
6708bb27	141	if (!atomic_read(&cmd->t_transport_active)) {
d050ffb9	142	spin_unlock(&cmd->t_state_lock);
c66ac9db NB	143	continue;
	144	}
	145	if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
d050ffb9	146	spin_unlock(&cmd->t_state_lock);
c66ac9db NB	147	continue;
c66ac9db NB	148	}
d050ffb9 NB	149	spin_unlock(&cmd->t_state_lock);
d050ffb9 NB	150
6eb40b2a	151	list_move_tail(&tmr_p->tmr_list, &drain_tmr_list);
d050ffb9 NB	152	}
	153	spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
	154
abc1fd4f	155	list_for_each_entry_safe(tmr_p, tmr_pp, &drain_tmr_list, tmr_list) {
b8a11d73	156	list_del_init(&tmr_p->tmr_list);
abc1fd4f	157	cmd = tmr_p->task_cmd;
d050ffb9	158
6708bb27	159	pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
c66ac9db	160	" Response: 0x%02x, t_state: %d\n",
abc1fd4f JE	161	(preempt_and_abort_list) ? "Preempt" : "", tmr_p,
abc1fd4f JE	162	tmr_p->function, tmr_p->response, cmd->t_state);
c66ac9db	163
8dc52b54	164	transport_cmd_finish_abort(cmd, 1);
c66ac9db	165	}
d050ffb9 NB	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;
c66ac9db NB	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) {
e3d6f909	204	if (!task->task_se_cmd) {
6708bb27	205	pr_err("task->task_se_cmd is NULL!\n");
c66ac9db NB	206	continue;
c66ac9db NB	207	}
e3d6f909	208	cmd = task->task_se_cmd;
c66ac9db	209
c66ac9db NB	210	/*
	211	* For PREEMPT_AND_ABORT usage, only process commands
	212	* with a matching reservation key.
	213	*/
6708bb27	214	if (preempt_and_abort_list &&
c66ac9db NB	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
d050ffb9	224	list_move_tail(&task->t_state_list, &drain_task_list);
c66ac9db	225	atomic_set(&task->task_state_active, 0);
d050ffb9 NB	226	/*
	227	* Remove from task execute list before processing drain_task_list
	228	*/
04629b7b CH	229	if (!list_empty(&task->t_execute_list))
04629b7b CH	230	__transport_remove_task_from_execute_queue(task, dev);
d050ffb9 NB	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;
c66ac9db	238
6708bb27	239	pr_debug("LUN_RESET: %s cmd: %p task: %p"
f2da9dbd CH	240	" ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state: %d"
f2da9dbd CH	241	"cdb: 0x%02x\n",
c66ac9db	242	(preempt_and_abort_list) ? "Preempt" : "", cmd, task,
e3d6f909 AG	243	cmd->se_tfo->get_task_tag(cmd), 0,
e3d6f909 AG	244	cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
f2da9dbd	245	cmd->t_task_cdb[0]);
6708bb27	246	pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx"
c66ac9db NB	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",
e3d6f909	250	cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key,
a1d8b49a AG	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));
c66ac9db	257
35e0e757 CH	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
cdbb70bb CH	268	spin_lock_irqsave(&cmd->t_state_lock, flags);
cdbb70bb CH	269	target_stop_task(task, &flags);
c66ac9db	270
6708bb27	271	if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
d050ffb9	272	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
6708bb27	273	pr_debug("LUN_RESET: Skipping task: %p, dev: %p for"
c66ac9db	274	" t_task_cdbs_ex_left: %d\n", task, dev,
a1d8b49a	275	atomic_read(&cmd->t_task_cdbs_ex_left));
c66ac9db NB	276	continue;
c66ac9db NB	277	}
a1d8b49a	278	fe_count = atomic_read(&cmd->t_fe_count);
c66ac9db	279
a1d8b49a	280	if (atomic_read(&cmd->t_transport_active)) {
6708bb27	281	pr_debug("LUN_RESET: got t_transport_active = 1 for"
c66ac9db NB	282	" task: %p, t_fe_count: %d dev: %p\n", task,
c66ac9db NB	283	fe_count, dev);
a1d8b49a	284	atomic_set(&cmd->t_transport_aborted, 1);
d050ffb9	285	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
c66ac9db	286
d050ffb9	287	core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
c66ac9db NB	288	continue;
c66ac9db NB	289	}
6708bb27	290	pr_debug("LUN_RESET: Got t_transport_active = 0 for task: %p,"
c66ac9db	291	" t_fe_count: %d dev: %p\n", task, fe_count, dev);
a1d8b49a AG	292	atomic_set(&cmd->t_transport_aborted, 1);
a1d8b49a AG	293	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
c66ac9db	294
d050ffb9	295	core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
c66ac9db	296	}
d050ffb9 NB	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;
c66ac9db NB	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);
5951146d	319	list_for_each_entry_safe(cmd, tcmd, &qobj->qobj_list, se_queue_node) {
c66ac9db NB	320	/*
	321	* For PREEMPT_AND_ABORT usage, only process commands
	322	* with a matching reservation key.
	323	*/
6708bb27	324	if (preempt_and_abort_list &&
c66ac9db NB	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
d050ffb9	334	atomic_set(&cmd->t_transport_queue_active, 0);
c66ac9db	335	atomic_dec(&qobj->queue_cnt);
d050ffb9 NB	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);
79a7fef2	342	list_del_init(&cmd->se_queue_node);
c66ac9db	343
6708bb27	344	pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:"
c66ac9db	345	" %d t_fe_count: %d\n", (preempt_and_abort_list) ?
5951146d	346	"Preempt" : "", cmd, cmd->t_state,
a1d8b49a	347	atomic_read(&cmd->t_fe_count));
c66ac9db NB	348
c66ac9db NB	349	core_tmr_handle_tas_abort(tmr_nacl, cmd, tas,
a1d8b49a	350	atomic_read(&cmd->t_fe_count));
c66ac9db	351	}
d050ffb9 NB	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_task_list(dev, prout_cmd, tmr_nacl, tas,
	395	preempt_and_abort_list);
	396	core_tmr_drain_cmd_list(dev, prout_cmd, tmr_nacl, tas,
	397	preempt_and_abort_list);
c66ac9db NB	398	/*
	399	* Clear any legacy SPC-2 reservation when called during
	400	* LOGICAL UNIT RESET
	401	*/
6708bb27	402	if (!preempt_and_abort_list &&
c66ac9db NB	403	(dev->dev_flags & DF_SPC2_RESERVATIONS)) {
	404	spin_lock(&dev->dev_reservation_lock);
	405	dev->dev_reserved_node_acl = NULL;
	406	dev->dev_flags &= ~DF_SPC2_RESERVATIONS;
	407	spin_unlock(&dev->dev_reservation_lock);
6708bb27	408	pr_debug("LUN_RESET: SCSI-2 Released reservation\n");
c66ac9db NB	409	}
c66ac9db NB	410
1e7de68c	411	spin_lock_irq(&dev->stats_lock);
c66ac9db	412	dev->num_resets++;
1e7de68c	413	spin_unlock_irq(&dev->stats_lock);
c66ac9db	414
6708bb27	415	pr_debug("LUN_RESET: %s for [%s] Complete\n",
c66ac9db	416	(preempt_and_abort_list) ? "Preempt" : "TMR",
e3d6f909	417	dev->transport->name);
c66ac9db NB	418	return 0;
c66ac9db NB	419	}
d050ffb9	420