| /******************************************************************************* |
| * Filename: target_core_tmr.c |
| * |
| * This file contains SPC-3 task management infrastructure |
| * |
| * (c) Copyright 2009-2013 Datera, Inc. |
| * |
| * 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 <target/target_core_base.h> |
| #include <target/target_core_backend.h> |
| #include <target/target_core_fabric.h> |
| |
| #include "target_core_internal.h" |
| #include "target_core_alua.h" |
| #include "target_core_pr.h" |
| |
| int 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 = kzalloc(sizeof(struct se_tmr_req), gfp_flags); |
| if (!tmr) { |
| pr_err("Unable to allocate struct se_tmr_req\n"); |
| return -ENOMEM; |
| } |
| |
| se_cmd->se_cmd_flags |= SCF_SCSI_TMR_CDB; |
| se_cmd->se_tmr_req = tmr; |
| tmr->task_cmd = se_cmd; |
| tmr->fabric_tmr_ptr = fabric_tmr_ptr; |
| tmr->function = function; |
| INIT_LIST_HEAD(&tmr->tmr_list); |
| |
| return 0; |
| } |
| 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) { |
| spin_lock_irqsave(&dev->se_tmr_lock, flags); |
| list_del(&tmr->tmr_list); |
| spin_unlock_irqrestore(&dev->se_tmr_lock, flags); |
| } |
| |
| kfree(tmr); |
| } |
| |
| static void core_tmr_handle_tas_abort( |
| struct se_node_acl *tmr_nacl, |
| struct se_cmd *cmd, |
| int tas) |
| { |
| bool remove = true; |
| /* |
| * TASK ABORTED status (TAS) bit support |
| */ |
| if ((tmr_nacl && (tmr_nacl != cmd->se_sess->se_node_acl)) && tas) { |
| remove = false; |
| transport_send_task_abort(cmd); |
| } |
| |
| transport_cmd_finish_abort(cmd, remove); |
| } |
| |
| static int target_check_cdb_and_preempt(struct list_head *list, |
| struct se_cmd *cmd) |
| { |
| struct t10_pr_registration *reg; |
| |
| if (!list) |
| return 0; |
| list_for_each_entry(reg, list, pr_reg_abort_list) { |
| if (reg->pr_res_key == cmd->pr_res_key) |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| void core_tmr_abort_task( |
| struct se_device *dev, |
| struct se_tmr_req *tmr, |
| struct se_session *se_sess) |
| { |
| struct se_cmd *se_cmd; |
| unsigned long flags; |
| u64 ref_tag; |
| |
| spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); |
| list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) { |
| |
| if (dev != se_cmd->se_dev) |
| continue; |
| |
| /* skip task management functions, including tmr->task_cmd */ |
| if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) |
| continue; |
| |
| ref_tag = se_cmd->tag; |
| if (tmr->ref_task_tag != ref_tag) |
| continue; |
| |
| if (!kref_get_unless_zero(&se_cmd->cmd_kref)) |
| continue; |
| |
| printk("ABORT_TASK: Found referenced %s task_tag: %llu\n", |
| se_cmd->se_tfo->get_fabric_name(), ref_tag); |
| |
| spin_lock(&se_cmd->t_state_lock); |
| if (se_cmd->transport_state & CMD_T_COMPLETE) { |
| printk("ABORT_TASK: ref_tag: %llu already complete," |
| " skipping\n", ref_tag); |
| spin_unlock(&se_cmd->t_state_lock); |
| spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); |
| |
| target_put_sess_cmd(se_cmd); |
| |
| goto out; |
| } |
| se_cmd->transport_state |= CMD_T_ABORTED; |
| spin_unlock(&se_cmd->t_state_lock); |
| |
| list_del_init(&se_cmd->se_cmd_list); |
| spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); |
| |
| cancel_work_sync(&se_cmd->work); |
| transport_wait_for_tasks(se_cmd); |
| |
| target_put_sess_cmd(se_cmd); |
| transport_cmd_finish_abort(se_cmd, true); |
| |
| printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for" |
| " ref_tag: %llu\n", ref_tag); |
| tmr->response = TMR_FUNCTION_COMPLETE; |
| return; |
| } |
| spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); |
| |
| out: |
| printk("ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST for ref_tag: %lld\n", |
| tmr->ref_task_tag); |
| tmr->response = TMR_TASK_DOES_NOT_EXIST; |
| } |
| |
| 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 (target_check_cdb_and_preempt(preempt_and_abort_list, cmd)) |
| continue; |
| |
| spin_lock(&cmd->t_state_lock); |
| if (!(cmd->transport_state & CMD_T_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_state_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, *next; |
| unsigned long flags; |
| |
| /* |
| * Complete outstanding commands 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(cmd, next, &dev->state_list, state_list) { |
| /* |
| * For PREEMPT_AND_ABORT usage, only process commands |
| * with a matching reservation key. |
| */ |
| if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd)) |
| continue; |
| |
| /* |
| * Not aborting PROUT PREEMPT_AND_ABORT CDB.. |
| */ |
| if (prout_cmd == cmd) |
| continue; |
| |
| list_move_tail(&cmd->state_list, &drain_task_list); |
| cmd->state_active = false; |
| } |
| spin_unlock_irqrestore(&dev->execute_task_lock, flags); |
| |
| while (!list_empty(&drain_task_list)) { |
| cmd = list_entry(drain_task_list.next, struct se_cmd, state_list); |
| list_del(&cmd->state_list); |
| |
| pr_debug("LUN_RESET: %s cmd: %p" |
| " ITT/CmdSN: 0x%08llx/0x%08x, i_state: %d, t_state: %d" |
| "cdb: 0x%02x\n", |
| (preempt_and_abort_list) ? "Preempt" : "", cmd, |
| cmd->tag, 0, |
| cmd->se_tfo->get_cmd_state(cmd), cmd->t_state, |
| cmd->t_task_cdb[0]); |
| pr_debug("LUN_RESET: ITT[0x%08llx] - pr_res_key: 0x%016Lx" |
| " -- CMD_T_ACTIVE: %d" |
| " CMD_T_STOP: %d CMD_T_SENT: %d\n", |
| cmd->tag, cmd->pr_res_key, |
| (cmd->transport_state & CMD_T_ACTIVE) != 0, |
| (cmd->transport_state & CMD_T_STOP) != 0, |
| (cmd->transport_state & CMD_T_SENT) != 0); |
| |
| /* |
| * 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_cmd(cmd, &flags); |
| |
| cmd->transport_state |= CMD_T_ABORTED; |
| spin_unlock_irqrestore(&cmd->t_state_lock, flags); |
| |
| core_tmr_handle_tas_abort(tmr_nacl, cmd, tas); |
| } |
| } |
| |
| 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->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_state_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_reservation_flags & DRF_SPC2_RESERVATIONS)) { |
| spin_lock(&dev->dev_reservation_lock); |
| dev->dev_reserved_node_acl = NULL; |
| dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS; |
| spin_unlock(&dev->dev_reservation_lock); |
| pr_debug("LUN_RESET: SCSI-2 Released reservation\n"); |
| } |
| |
| atomic_long_inc(&dev->num_resets); |
| |
| pr_debug("LUN_RESET: %s for [%s] Complete\n", |
| (preempt_and_abort_list) ? "Preempt" : "TMR", |
| dev->transport->name); |
| return 0; |
| } |
| |