diff options
Diffstat (limited to 'drivers/target/target_core_transport.c')
-rw-r--r-- | drivers/target/target_core_transport.c | 124 |
1 files changed, 86 insertions, 38 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 14c6f2bb1b01..7838dc20f713 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -676,6 +676,21 @@ static void target_remove_from_state_list(struct se_cmd *cmd) spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags); } +static void target_remove_from_tmr_list(struct se_cmd *cmd) +{ + struct se_device *dev = NULL; + unsigned long flags; + + if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) + dev = cmd->se_tmr_req->tmr_dev; + + if (dev) { + spin_lock_irqsave(&dev->se_tmr_lock, flags); + if (cmd->se_tmr_req->tmr_dev) + list_del_init(&cmd->se_tmr_req->tmr_list); + spin_unlock_irqrestore(&dev->se_tmr_lock, flags); + } +} /* * This function is called by the target core after the target core has * finished processing a SCSI command or SCSI TMF. Both the regular command @@ -687,13 +702,6 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd) { unsigned long flags; - target_remove_from_state_list(cmd); - - /* - * Clear struct se_cmd->se_lun before the handoff to FE. - */ - cmd->se_lun = NULL; - spin_lock_irqsave(&cmd->t_state_lock, flags); /* * Determine if frontend context caller is requesting the stopping of @@ -728,8 +736,16 @@ static void transport_lun_remove_cmd(struct se_cmd *cmd) if (!lun) return; + target_remove_from_state_list(cmd); + target_remove_from_tmr_list(cmd); + if (cmpxchg(&cmd->lun_ref_active, true, false)) percpu_ref_put(&lun->lun_ref); + + /* + * Clear struct se_cmd->se_lun before the handoff to FE. + */ + cmd->se_lun = NULL; } static void target_complete_failure_work(struct work_struct *work) @@ -1511,10 +1527,10 @@ target_cmd_parse_cdb(struct se_cmd *cmd) ret = dev->transport->parse_cdb(cmd); if (ret == TCM_UNSUPPORTED_SCSI_OPCODE) - pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n", - cmd->se_tfo->fabric_name, - cmd->se_sess->se_node_acl->initiatorname, - cmd->t_task_cdb[0]); + pr_debug_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n", + cmd->se_tfo->fabric_name, + cmd->se_sess->se_node_acl->initiatorname, + cmd->t_task_cdb[0]); if (ret) return ret; @@ -2173,32 +2189,39 @@ static bool target_handle_task_attr(struct se_cmd *cmd) */ switch (cmd->sam_task_attr) { case TCM_HEAD_TAG: + atomic_inc_mb(&dev->non_ordered); pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n", cmd->t_task_cdb[0]); return false; case TCM_ORDERED_TAG: - atomic_inc_mb(&dev->dev_ordered_sync); + atomic_inc_mb(&dev->delayed_cmd_count); pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n", cmd->t_task_cdb[0]); - - /* - * Execute an ORDERED command if no other older commands - * exist that need to be completed first. - */ - if (!atomic_read(&dev->simple_cmds)) - return false; break; default: /* * For SIMPLE and UNTAGGED Task Attribute commands */ - atomic_inc_mb(&dev->simple_cmds); + atomic_inc_mb(&dev->non_ordered); + + if (atomic_read(&dev->delayed_cmd_count) == 0) + return false; break; } - if (atomic_read(&dev->dev_ordered_sync) == 0) - return false; + if (cmd->sam_task_attr != TCM_ORDERED_TAG) { + atomic_inc_mb(&dev->delayed_cmd_count); + /* + * We will account for this when we dequeue from the delayed + * list. + */ + atomic_dec_mb(&dev->non_ordered); + } + + spin_lock_irq(&cmd->t_state_lock); + cmd->transport_state &= ~CMD_T_SENT; + spin_unlock_irq(&cmd->t_state_lock); spin_lock(&dev->delayed_cmd_lock); list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list); @@ -2206,6 +2229,12 @@ static bool target_handle_task_attr(struct se_cmd *cmd) pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn", cmd->t_task_cdb[0], cmd->sam_task_attr); + /* + * We may have no non ordered cmds when this function started or we + * could have raced with the last simple/head cmd completing, so kick + * the delayed handler here. + */ + schedule_work(&dev->delayed_cmd_work); return true; } @@ -2228,12 +2257,8 @@ void target_execute_cmd(struct se_cmd *cmd) if (target_write_prot_action(cmd)) return; - if (target_handle_task_attr(cmd)) { - spin_lock_irq(&cmd->t_state_lock); - cmd->transport_state &= ~CMD_T_SENT; - spin_unlock_irq(&cmd->t_state_lock); + if (target_handle_task_attr(cmd)) return; - } __target_execute_cmd(cmd, true); } @@ -2243,29 +2268,48 @@ EXPORT_SYMBOL(target_execute_cmd); * Process all commands up to the last received ORDERED task attribute which * requires another blocking boundary */ -static void target_restart_delayed_cmds(struct se_device *dev) +void target_do_delayed_work(struct work_struct *work) { - for (;;) { + struct se_device *dev = container_of(work, struct se_device, + delayed_cmd_work); + + spin_lock(&dev->delayed_cmd_lock); + while (!dev->ordered_sync_in_progress) { struct se_cmd *cmd; - spin_lock(&dev->delayed_cmd_lock); - if (list_empty(&dev->delayed_cmd_list)) { - spin_unlock(&dev->delayed_cmd_lock); + if (list_empty(&dev->delayed_cmd_list)) break; - } cmd = list_entry(dev->delayed_cmd_list.next, struct se_cmd, se_delayed_node); + + if (cmd->sam_task_attr == TCM_ORDERED_TAG) { + /* + * Check if we started with: + * [ordered] [simple] [ordered] + * and we are now at the last ordered so we have to wait + * for the simple cmd. + */ + if (atomic_read(&dev->non_ordered) > 0) + break; + + dev->ordered_sync_in_progress = true; + } + list_del(&cmd->se_delayed_node); + atomic_dec_mb(&dev->delayed_cmd_count); spin_unlock(&dev->delayed_cmd_lock); + if (cmd->sam_task_attr != TCM_ORDERED_TAG) + atomic_inc_mb(&dev->non_ordered); + cmd->transport_state |= CMD_T_SENT; __target_execute_cmd(cmd, true); - if (cmd->sam_task_attr == TCM_ORDERED_TAG) - break; + spin_lock(&dev->delayed_cmd_lock); } + spin_unlock(&dev->delayed_cmd_lock); } /* @@ -2283,14 +2327,17 @@ static void transport_complete_task_attr(struct se_cmd *cmd) goto restart; if (cmd->sam_task_attr == TCM_SIMPLE_TAG) { - atomic_dec_mb(&dev->simple_cmds); + atomic_dec_mb(&dev->non_ordered); dev->dev_cur_ordered_id++; } else if (cmd->sam_task_attr == TCM_HEAD_TAG) { + atomic_dec_mb(&dev->non_ordered); dev->dev_cur_ordered_id++; pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n", dev->dev_cur_ordered_id); } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) { - atomic_dec_mb(&dev->dev_ordered_sync); + spin_lock(&dev->delayed_cmd_lock); + dev->ordered_sync_in_progress = false; + spin_unlock(&dev->delayed_cmd_lock); dev->dev_cur_ordered_id++; pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n", @@ -2299,7 +2346,8 @@ static void transport_complete_task_attr(struct se_cmd *cmd) cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET; restart: - target_restart_delayed_cmds(dev); + if (atomic_read(&dev->delayed_cmd_count) > 0) + schedule_work(&dev->delayed_cmd_work); } static void transport_complete_qf(struct se_cmd *cmd) |