]> git.karo-electronics.de Git - mv-sheeva.git/blobdiff - drivers/target/target_core_tmr.c
Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[mv-sheeva.git] / drivers / target / target_core_tmr.c
diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c
new file mode 100644 (file)
index 0000000..4a10983
--- /dev/null
@@ -0,0 +1,409 @@
+/*******************************************************************************
+ * 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);
+               } else {
+                       if (atomic_read(&task->task_execute_queue) != 0)
+                               transport_remove_task_from_execute_queue(task, dev);
+               }
+               __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);
+                       atomic_set(&T_TASK(cmd)->t_transport_aborted, 1);
+                       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);
+               atomic_set(&T_TASK(cmd)->t_transport_aborted, 1);
+               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;
+}