Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvar...
[linux-2.6.git] / drivers / target / target_core_tmr.c
index 27d4925..f015839 100644 (file)
  *
  ******************************************************************************/
 
-#include <linux/version.h>
 #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_backend.h>
+#include <target/target_core_fabric.h>
 #include <target/target_core_configfs.h>
 
+#include "target_core_internal.h"
 #include "target_core_alua.h"
 #include "target_core_pr.h"
 
-struct se_tmr_req *core_tmr_alloc_req(
+int core_tmr_alloc_req(
        struct se_cmd *se_cmd,
        void *fabric_tmr_ptr,
-       u8 function)
+       u8 function,
+       gfp_t gfp_flags)
 {
        struct se_tmr_req *tmr;
 
-       tmr = kmem_cache_zalloc(se_tmr_req_cache, (in_interrupt()) ?
-                                       GFP_ATOMIC : GFP_KERNEL);
+       tmr = kzalloc(sizeof(struct se_tmr_req), gfp_flags);
        if (!tmr) {
                pr_err("Unable to allocate struct se_tmr_req\n");
-               return ERR_PTR(-ENOMEM);
+               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 tmr;
+       return 0;
 }
 EXPORT_SYMBOL(core_tmr_alloc_req);
 
@@ -67,17 +69,18 @@ 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);
+               kfree(tmr);
                return;
        }
 
-       spin_lock_irq(&dev->se_tmr_lock);
+       spin_lock_irqsave(&dev->se_tmr_lock, flags);
        list_del(&tmr->tmr_list);
-       spin_unlock_irq(&dev->se_tmr_lock);
+       spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
 
-       kmem_cache_free(se_tmr_req_cache, tmr);
+       kfree(tmr);
 }
 
 static void core_tmr_handle_tas_abort(
@@ -100,59 +103,104 @@ static void core_tmr_handle_tas_abort(
        transport_cmd_finish_abort(cmd, 0);
 }
 
-int core_tmr_lun_reset(
+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 list_head *preempt_and_abort_list,
-       struct se_cmd *prout_cmd)
+       struct se_session *se_sess)
 {
-       struct se_cmd *cmd, *tcmd;
-       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;
+       struct se_cmd *se_cmd, *tmp_cmd;
        unsigned long flags;
-       int fe_count, 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);
+       int ref_tag;
+
+       spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
+       list_for_each_entry_safe(se_cmd, tmp_cmd,
+                       &se_sess->sess_cmd_list, se_cmd_list) {
+
+               if (dev != se_cmd->se_dev)
+                       continue;
+               ref_tag = se_cmd->se_tfo->get_task_tag(se_cmd);
+               if (tmr->ref_task_tag != ref_tag)
+                       continue;
+
+               printk("ABORT_TASK: Found referenced %s task_tag: %u\n",
+                       se_cmd->se_tfo->get_fabric_name(), ref_tag);
+
+               spin_lock_irq(&se_cmd->t_state_lock);
+               if (se_cmd->transport_state & CMD_T_COMPLETE) {
+                       printk("ABORT_TASK: ref_tag: %u already complete, skipping\n", ref_tag);
+                       spin_unlock_irq(&se_cmd->t_state_lock);
+                       spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+                       goto out;
                }
+               se_cmd->transport_state |= CMD_T_ABORTED;
+               spin_unlock_irq(&se_cmd->t_state_lock);
+
+               list_del_init(&se_cmd->se_cmd_list);
+               kref_get(&se_cmd->cmd_kref);
+               spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+
+               cancel_work_sync(&se_cmd->work);
+               transport_wait_for_tasks(se_cmd);
+               /*
+                * Now send SAM_STAT_TASK_ABORTED status for the referenced
+                * se_cmd descriptor..
+                */
+               transport_send_task_abort(se_cmd);
+               /*
+                * Also deal with possible extra acknowledge reference..
+                */
+               if (se_cmd->se_cmd_flags & SCF_ACK_KREF)
+                       target_put_sess_cmd(se_sess, se_cmd);
+
+               target_put_sess_cmd(se_sess, se_cmd);
+
+               printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for"
+                               " ref_tag: %d\n", ref_tag);
+               tmr->response = TMR_FUNCTION_COMPLETE;
+               return;
        }
-       pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
-               (preempt_and_abort_list) ? "Preempt" : "TMR",
-               dev->transport->name, tas);
+       spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+
+out:
+       printk("ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST for ref_tag: %d\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_irq(&dev->se_tmr_lock);
+       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 && (tmr_p == tmr))
+               if (tmr_p == tmr)
                        continue;
 
                cmd = tmr_p->task_cmd;
@@ -165,33 +213,49 @@ int core_tmr_lun_reset(
                 * 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))
+               if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
                        continue;
-               spin_unlock_irq(&dev->se_tmr_lock);
 
-               spin_lock_irqsave(&cmd->t_state_lock, flags);
-               if (!atomic_read(&cmd->t_transport_active)) {
-                       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-                       spin_lock_irq(&dev->se_tmr_lock);
+               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_irqrestore(&cmd->t_state_lock, flags);
-                       spin_lock_irq(&dev->se_tmr_lock);
+                       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);
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-               transport_cmd_finish_abort_tmr(cmd);
-               spin_lock_irq(&dev->se_tmr_lock);
+               transport_cmd_finish_abort(cmd, 1);
        }
-       spin_unlock_irq(&dev->se_tmr_lock);
+}
+
+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
@@ -226,9 +290,7 @@ int core_tmr_lun_reset(
                 * 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))
+               if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
                        continue;
                /*
                 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
@@ -236,84 +298,92 @@ int core_tmr_lun_reset(
                if (prout_cmd == cmd)
                        continue;
 
+               list_move_tail(&task->t_state_list, &drain_task_list);
+               task->t_state_active = false;
+               /*
+                * 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);
-               atomic_set(&task->task_state_active, 0);
-               spin_unlock_irqrestore(&dev->execute_task_lock, flags);
+               cmd = task->task_se_cmd;
 
-               spin_lock_irqsave(&cmd->t_state_lock, flags);
                pr_debug("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",
+                       " 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->deferred_t_state, cmd->t_task_cdb[0]);
+                       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",
+                       " t_task_cdbs_sent: %d -- CMD_T_ACTIVE: %d"
+                       " CMD_T_STOP: %d CMD_T_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 (atomic_read(&task->task_active)) {
-                       atomic_set(&task->task_stop, 1);
-                       spin_unlock_irqrestore(
-                               &cmd->t_state_lock, flags);
-
-                       pr_debug("LUN_RESET: Waiting for task: %p to shutdown"
-                               " for dev: %p\n", task, dev);
-                       wait_for_completion(&task->task_stop_comp);
-                       pr_debug("LUN_RESET Completed task: %p shutdown for"
-                               " dev: %p\n", task, dev);
-                       spin_lock_irqsave(&cmd->t_state_lock, flags);
-                       atomic_dec(&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);
+                       (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_task(task, &flags);
 
                if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
-                       spin_unlock_irqrestore(
-                                       &cmd->t_state_lock, flags);
+                       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));
-
-                       spin_lock_irqsave(&dev->execute_task_lock, flags);
                        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"
+               if (!(cmd->transport_state & CMD_T_ACTIVE)) {
+                       pr_debug("LUN_RESET: got CMD_T_ACTIVE 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);
+                       cmd->transport_state |= CMD_T_ABORTED;
+                       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-                       spin_lock_irqsave(&dev->execute_task_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,"
+               pr_debug("LUN_RESET: Got !CMD_T_ACTIVE for task: %p,"
                        " t_fe_count: %d dev: %p\n", task, fe_count, dev);
-               atomic_set(&cmd->t_transport_aborted, 1);
+               cmd->transport_state |= CMD_T_ABORTED;
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
 
-               spin_lock_irqsave(&dev->execute_task_lock, flags);
+               core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
        }
-       spin_unlock_irqrestore(&dev->execute_task_lock, flags);
+}
+
+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.
         *
@@ -328,9 +398,7 @@ int core_tmr_lun_reset(
                 * 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))
+               if (target_check_cdb_and_preempt(preempt_and_abort_list, cmd))
                        continue;
                /*
                 * Not aborting PROUT PREEMPT_AND_ABORT CDB..
@@ -338,25 +406,70 @@ int core_tmr_lun_reset(
                if (prout_cmd == cmd)
                        continue;
 
-               atomic_dec(&cmd->t_transport_queue_active);
+               cmd->transport_state &= ~CMD_T_QUEUED;
                atomic_dec(&qobj->queue_cnt);
-               list_del(&cmd->se_queue_node);
-               spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
+               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));
-               /*
-                * Signal that the command has failed via cmd->se_cmd_flags,
-                */
-               transport_new_cmd_failure(cmd);
 
                core_tmr_handle_tas_abort(tmr_nacl, cmd, tas,
                                atomic_read(&cmd->t_fe_count));
-               spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
        }
-       spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
+}
+
+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
@@ -379,3 +492,4 @@ int core_tmr_lun_reset(
                        dev->transport->name);
        return 0;
 }
+