diff options
Diffstat (limited to 'drivers/target/target_core_tmr.c')
-rw-r--r-- | drivers/target/target_core_tmr.c | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c new file mode 100644 index 0000000..158cecb --- /dev/null +++ b/drivers/target/target_core_tmr.c @@ -0,0 +1,404 @@ +/******************************************************************************* + * 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/version.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/list.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" + +#define DEBUG_LUN_RESET +#ifdef DEBUG_LUN_RESET +#define DEBUG_LR(x...) printk(KERN_INFO x) +#else +#define DEBUG_LR(x...) +#endif + +struct se_tmr_req *core_tmr_alloc_req( + struct se_cmd *se_cmd, + void *fabric_tmr_ptr, + u8 function) +{ + struct se_tmr_req *tmr; + + tmr = kmem_cache_zalloc(se_tmr_req_cache, GFP_KERNEL); + if (!(tmr)) { + printk(KERN_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; + + spin_lock(&dev->se_tmr_lock); + list_del(&tmr->tmr_list); + kmem_cache_free(se_tmr_req_cache, tmr); + spin_unlock(&dev->se_tmr_lock); +} + +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 != NULL) && + (tmr_nacl == cmd->se_sess->se_node_acl)) || tas) + transport_send_task_abort(cmd); + + transport_cmd_finish_abort(cmd, 0); +} + +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_cmd *cmd; + struct se_queue_req *qr, *qr_tmp; + struct se_node_acl *tmr_nacl = NULL; + struct se_portal_group *tmr_tpg = NULL; + struct se_queue_obj *qobj = dev->dev_queue_obj; + struct se_tmr_req *tmr_p, *tmr_pp; + struct se_task *task, *task_tmp; + unsigned long flags; + int fe_count, state, 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_ATTRIB(dev)->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) { + DEBUG_LR("LUN_RESET: TMR caller fabric: %s" + " initiator port %s\n", + TPG_TFO(tmr_tpg)->get_fabric_name(), + tmr_nacl->initiatorname); + } + } + DEBUG_LR("LUN_RESET: %s starting for [%s], tas: %d\n", + (preempt_and_abort_list) ? "Preempt" : "TMR", + TRANSPORT(dev)->name, tas); + /* + * Release all pending and outgoing TMRs aside from the received + * LUN_RESET tmr.. + */ + spin_lock(&dev->se_tmr_lock); + 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 && (tmr_p == tmr)) + continue; + + cmd = tmr_p->task_cmd; + if (!(cmd)) { + printk(KERN_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 != NULL) && + (core_scsi3_check_cdb_abort_and_preempt( + preempt_and_abort_list, cmd) != 0)) + continue; + spin_unlock(&dev->se_tmr_lock); + + spin_lock_irqsave(&T_TASK(cmd)->t_state_lock, flags); + if (!(atomic_read(&T_TASK(cmd)->t_transport_active))) { + spin_unlock_irqrestore(&T_TASK(cmd)->t_state_lock, flags); + spin_lock(&dev->se_tmr_lock); + continue; + } + if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) { + spin_unlock_irqrestore(&T_TASK(cmd)->t_state_lock, flags); + spin_lock(&dev->se_tmr_lock); + continue; + } + DEBUG_LR("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); + spin_unlock_irqrestore(&T_TASK(cmd)->t_state_lock, flags); + + transport_cmd_finish_abort_tmr(cmd); + spin_lock(&dev->se_tmr_lock); + } + spin_unlock(&dev->se_tmr_lock); + /* + * 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_CMD(task))) { + printk(KERN_ERR "TASK_CMD(task) is NULL!\n"); + continue; + } + cmd = TASK_CMD(task); + + if (!T_TASK(cmd)) { + printk(KERN_ERR "T_TASK(cmd) is NULL for task: %p cmd:" + " %p ITT: 0x%08x\n", task, cmd, + CMD_TFO(cmd)->get_task_tag(cmd)); + continue; + } + /* + * For PREEMPT_AND_ABORT usage, only process commands + * with a matching reservation key. + */ + if ((preempt_and_abort_list != NULL) && + (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_del(&task->t_state_list); + atomic_set(&task->task_state_active, 0); + spin_unlock_irqrestore(&dev->execute_task_lock, flags); + + spin_lock_irqsave(&T_TASK(cmd)->t_state_lock, flags); + DEBUG_LR("LUN_RESET: %s cmd: %p task: %p" + " ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state/" + "def_t_state: %d/%d cdb: 0x%02x\n", + (preempt_and_abort_list) ? "Preempt" : "", cmd, task, + CMD_TFO(cmd)->get_task_tag(cmd), 0, + CMD_TFO(cmd)->get_cmd_state(cmd), cmd->t_state, + cmd->deferred_t_state, T_TASK(cmd)->t_task_cdb[0]); + DEBUG_LR("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_TFO(cmd)->get_task_tag(cmd), cmd->pr_res_key, + T_TASK(cmd)->t_task_cdbs, + atomic_read(&T_TASK(cmd)->t_task_cdbs_left), + atomic_read(&T_TASK(cmd)->t_task_cdbs_sent), + atomic_read(&T_TASK(cmd)->t_transport_active), + atomic_read(&T_TASK(cmd)->t_transport_stop), + atomic_read(&T_TASK(cmd)->t_transport_sent)); + + if (atomic_read(&task->task_active)) { + atomic_set(&task->task_stop, 1); + spin_unlock_irqrestore( + &T_TASK(cmd)->t_state_lock, flags); + + DEBUG_LR("LUN_RESET: Waiting for task: %p to shutdown" + " for dev: %p\n", task, dev); + wait_for_completion(&task->task_stop_comp); + DEBUG_LR("LUN_RESET Completed task: %p shutdown for" + " dev: %p\n", task, dev); + spin_lock_irqsave(&T_TASK(cmd)->t_state_lock, flags); + atomic_dec(&T_TASK(cmd)->t_task_cdbs_left); + + atomic_set(&task->task_active, 0); + atomic_set(&task->task_stop, 0); + } + __transport_stop_task_timer(task, &flags); + + if (!(atomic_dec_and_test(&T_TASK(cmd)->t_task_cdbs_ex_left))) { + spin_unlock_irqrestore( + &T_TASK(cmd)->t_state_lock, flags); + DEBUG_LR("LUN_RESET: Skipping task: %p, dev: %p for" + " t_task_cdbs_ex_left: %d\n", task, dev, + atomic_read(&T_TASK(cmd)->t_task_cdbs_ex_left)); + + spin_lock_irqsave(&dev->execute_task_lock, flags); + continue; + } + fe_count = atomic_read(&T_TASK(cmd)->t_fe_count); + + if (atomic_read(&T_TASK(cmd)->t_transport_active)) { + DEBUG_LR("LUN_RESET: got t_transport_active = 1 for" + " task: %p, t_fe_count: %d dev: %p\n", task, + fe_count, dev); + spin_unlock_irqrestore(&T_TASK(cmd)->t_state_lock, + flags); + core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); + + spin_lock_irqsave(&dev->execute_task_lock, flags); + continue; + } + DEBUG_LR("LUN_RESET: Got t_transport_active = 0 for task: %p," + " t_fe_count: %d dev: %p\n", task, fe_count, dev); + spin_unlock_irqrestore(&T_TASK(cmd)->t_state_lock, flags); + core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count); + + spin_lock_irqsave(&dev->execute_task_lock, flags); + } + spin_unlock_irqrestore(&dev->execute_task_lock, 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(qr, qr_tmp, &qobj->qobj_list, qr_list) { + cmd = (struct se_cmd *)qr->cmd; + if (!(cmd)) { + /* + * Skip these for non PREEMPT_AND_ABORT usage.. + */ + if (preempt_and_abort_list != NULL) + continue; + + atomic_dec(&qobj->queue_cnt); + list_del(&qr->qr_list); + kfree(qr); + continue; + } + /* + * For PREEMPT_AND_ABORT usage, only process commands + * with a matching reservation key. + */ + if ((preempt_and_abort_list != NULL) && + (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_dec(&T_TASK(cmd)->t_transport_queue_active); + atomic_dec(&qobj->queue_cnt); + list_del(&qr->qr_list); + spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags); + + state = qr->state; + kfree(qr); + + DEBUG_LR("LUN_RESET: %s from Device Queue: cmd: %p t_state:" + " %d t_fe_count: %d\n", (preempt_and_abort_list) ? + "Preempt" : "", cmd, state, + atomic_read(&T_TASK(cmd)->t_fe_count)); + /* + * Signal that the command has failed via cmd->se_cmd_flags, + * and call TFO->new_cmd_failure() to wakeup any fabric + * dependent code used to wait for unsolicited data out + * allocation to complete. The fabric module is expected + * to dump any remaining unsolicited data out for the aborted + * command at this point. + */ + transport_new_cmd_failure(cmd); + + core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, + atomic_read(&T_TASK(cmd)->t_fe_count)); + spin_lock_irqsave(&qobj->cmd_queue_lock, flags); + } + spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags); + /* + * 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); + printk(KERN_INFO "LUN_RESET: SCSI-2 Released reservation\n"); + } + + spin_lock(&dev->stats_lock); + dev->num_resets++; + spin_unlock(&dev->stats_lock); + + DEBUG_LR("LUN_RESET: %s for [%s] Complete\n", + (preempt_and_abort_list) ? "Preempt" : "TMR", + TRANSPORT(dev)->name); + return 0; +} |