diff options
Diffstat (limited to 'drivers/target/target_core_transport.c')
-rw-r--r-- | drivers/target/target_core_transport.c | 230 |
1 files changed, 119 insertions, 111 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 32457fd7a736..45c8fd13b845 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -707,32 +707,6 @@ static void transport_lun_remove_cmd(struct se_cmd *cmd) percpu_ref_put(&lun->lun_ref); } -int transport_cmd_finish_abort(struct se_cmd *cmd) -{ - bool send_tas = cmd->transport_state & CMD_T_TAS; - bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF); - int ret = 0; - - if (send_tas) - transport_send_task_abort(cmd); - - if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) - transport_lun_remove_cmd(cmd); - /* - * Allow the fabric driver to unmap any resources before - * releasing the descriptor via TFO->release_cmd() - */ - if (!send_tas) - cmd->se_tfo->aborted_task(cmd); - - if (transport_cmd_check_stop_to_fabric(cmd)) - return 1; - if (!send_tas && ack_kref) - ret = target_put_sess_cmd(cmd); - - return ret; -} - static void target_complete_failure_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); @@ -782,12 +756,88 @@ void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense) } EXPORT_SYMBOL(transport_copy_sense_to_cmd); +static void target_handle_abort(struct se_cmd *cmd) +{ + bool tas = cmd->transport_state & CMD_T_TAS; + bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF; + int ret; + + pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas); + + if (tas) { + if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) { + cmd->scsi_status = SAM_STAT_TASK_ABORTED; + pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n", + cmd->t_task_cdb[0], cmd->tag); + trace_target_cmd_complete(cmd); + ret = cmd->se_tfo->queue_status(cmd); + if (ret) { + transport_handle_queue_full(cmd, cmd->se_dev, + ret, false); + return; + } + } else { + cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED; + cmd->se_tfo->queue_tm_rsp(cmd); + } + } else { + /* + * Allow the fabric driver to unmap any resources before + * releasing the descriptor via TFO->release_cmd(). + */ + cmd->se_tfo->aborted_task(cmd); + if (ack_kref) + WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0); + /* + * To do: establish a unit attention condition on the I_T + * nexus associated with cmd. See also the paragraph "Aborting + * commands" in SAM. + */ + } + + WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0); + + transport_lun_remove_cmd(cmd); + + transport_cmd_check_stop_to_fabric(cmd); +} + +static void target_abort_work(struct work_struct *work) +{ + struct se_cmd *cmd = container_of(work, struct se_cmd, work); + + target_handle_abort(cmd); +} + +static bool target_cmd_interrupted(struct se_cmd *cmd) +{ + int post_ret; + + if (cmd->transport_state & CMD_T_ABORTED) { + if (cmd->transport_complete_callback) + cmd->transport_complete_callback(cmd, false, &post_ret); + INIT_WORK(&cmd->work, target_abort_work); + queue_work(target_completion_wq, &cmd->work); + return true; + } else if (cmd->transport_state & CMD_T_STOP) { + if (cmd->transport_complete_callback) + cmd->transport_complete_callback(cmd, false, &post_ret); + complete_all(&cmd->t_transport_stop_comp); + return true; + } + + return false; +} + +/* May be called from interrupt context so must not sleep. */ void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status) { - struct se_device *dev = cmd->se_dev; int success; unsigned long flags; + if (target_cmd_interrupted(cmd)) + return; + cmd->scsi_status = scsi_status; spin_lock_irqsave(&cmd->t_state_lock, flags); @@ -803,25 +853,7 @@ void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status) break; } - /* - * Check for case where an explicit ABORT_TASK has been received - * and transport_wait_for_tasks() will be waiting for completion.. - */ - if (cmd->transport_state & CMD_T_ABORTED || - cmd->transport_state & CMD_T_STOP) { - spin_unlock_irqrestore(&cmd->t_state_lock, flags); - /* - * If COMPARE_AND_WRITE was stopped by __transport_wait_for_tasks(), - * release se_device->caw_sem obtained by sbc_compare_and_write() - * since target_complete_ok_work() or target_complete_failure_work() - * won't be called to invoke the normal CAW completion callbacks. - */ - if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) { - up(&dev->caw_sem); - } - complete_all(&cmd->t_transport_stop_comp); - return; - } else if (!success) { + if (!success) { INIT_WORK(&cmd->work, target_complete_failure_work); } else { INIT_WORK(&cmd->work, target_complete_ok_work); @@ -1805,8 +1837,11 @@ void transport_generic_request_failure(struct se_cmd *cmd, if (cmd->transport_complete_callback) cmd->transport_complete_callback(cmd, false, NULL); - if (cmd->transport_state & CMD_T_ABORTED) + if (cmd->transport_state & CMD_T_ABORTED) { + INIT_WORK(&cmd->work, target_abort_work); + queue_work(target_completion_wq, &cmd->work); return; + } switch (sense_reason) { case TCM_NON_EXISTENT_LUN: @@ -2020,20 +2055,10 @@ void target_execute_cmd(struct se_cmd *cmd) * * If the received CDB has already been aborted stop processing it here. */ - spin_lock_irq(&cmd->t_state_lock); - if (cmd->transport_state & CMD_T_ABORTED) { - spin_unlock_irq(&cmd->t_state_lock); - return; - } - if (cmd->transport_state & CMD_T_STOP) { - pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n", - __func__, __LINE__, cmd->tag); - - spin_unlock_irq(&cmd->t_state_lock); - complete_all(&cmd->t_transport_stop_comp); + if (target_cmd_interrupted(cmd)) return; - } + spin_lock_irq(&cmd->t_state_lock); cmd->t_state = TRANSPORT_PROCESSING; cmd->transport_state &= ~CMD_T_PRE_EXECUTE; cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT; @@ -2647,13 +2672,29 @@ static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas) } /* + * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has + * finished. + */ +void target_put_cmd_and_wait(struct se_cmd *cmd) +{ + DECLARE_COMPLETION_ONSTACK(compl); + + WARN_ON_ONCE(cmd->abrt_compl); + cmd->abrt_compl = &compl; + target_put_sess_cmd(cmd); + wait_for_completion(&compl); +} + +/* * This function is called by frontend drivers after processing of a command * has finished. * - * The protocol for ensuring that either the regular flow or the TMF - * code drops one reference is as follows: + * The protocol for ensuring that either the regular frontend command + * processing flow or target_handle_abort() code drops one reference is as + * follows: * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause - * the frontend driver to drop one reference, synchronously or asynchronously. + * the frontend driver to call this function synchronously or asynchronously. + * That will cause one reference to be dropped. * - During regular command processing the target core sets CMD_T_COMPLETE * before invoking one of the .queue_*() functions. * - The code that aborts commands skips commands and TMFs for which @@ -2665,7 +2706,7 @@ static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas) * - For aborted commands for which CMD_T_TAS has been set .queue_status() will * be called and will drop a reference. * - For aborted commands for which CMD_T_TAS has not been set .aborted_task() - * will be called. transport_cmd_finish_abort() will drop the final reference. + * will be called. target_handle_abort() will drop the final reference. */ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks) { @@ -2690,8 +2731,7 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks) } if (aborted) cmd->free_compl = &compl; - if (!aborted || tas) - ret = target_put_sess_cmd(cmd); + ret = target_put_sess_cmd(cmd); if (aborted) { pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag); wait_for_completion(&compl); @@ -3219,6 +3259,8 @@ transport_send_check_condition_and_sense(struct se_cmd *cmd, { unsigned long flags; + WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB); + spin_lock_irqsave(&cmd->t_state_lock, flags); if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) { spin_unlock_irqrestore(&cmd->t_state_lock, flags); @@ -3235,46 +3277,15 @@ transport_send_check_condition_and_sense(struct se_cmd *cmd, } EXPORT_SYMBOL(transport_send_check_condition_and_sense); -void transport_send_task_abort(struct se_cmd *cmd) -{ - unsigned long flags; - int ret; - - spin_lock_irqsave(&cmd->t_state_lock, flags); - if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) { - spin_unlock_irqrestore(&cmd->t_state_lock, flags); - return; - } - spin_unlock_irqrestore(&cmd->t_state_lock, flags); - - cmd->scsi_status = SAM_STAT_TASK_ABORTED; - - transport_lun_remove_cmd(cmd); - - pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n", - cmd->t_task_cdb[0], cmd->tag); - - trace_target_cmd_complete(cmd); - ret = cmd->se_tfo->queue_status(cmd); - if (ret) - transport_handle_queue_full(cmd, cmd->se_dev, ret, false); -} - static void target_tmr_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); struct se_device *dev = cmd->se_dev; struct se_tmr_req *tmr = cmd->se_tmr_req; - unsigned long flags; int ret; - spin_lock_irqsave(&cmd->t_state_lock, flags); - if (cmd->transport_state & CMD_T_ABORTED) { - tmr->response = TMR_FUNCTION_REJECTED; - spin_unlock_irqrestore(&cmd->t_state_lock, flags); - goto check_stop; - } - spin_unlock_irqrestore(&cmd->t_state_lock, flags); + if (cmd->transport_state & CMD_T_ABORTED) + goto aborted; switch (tmr->function) { case TMR_ABORT_TASK: @@ -3308,18 +3319,16 @@ static void target_tmr_work(struct work_struct *work) break; } - spin_lock_irqsave(&cmd->t_state_lock, flags); - if (cmd->transport_state & CMD_T_ABORTED) { - spin_unlock_irqrestore(&cmd->t_state_lock, flags); - goto check_stop; - } - spin_unlock_irqrestore(&cmd->t_state_lock, flags); + if (cmd->transport_state & CMD_T_ABORTED) + goto aborted; cmd->se_tfo->queue_tm_rsp(cmd); -check_stop: - transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); + return; + +aborted: + target_handle_abort(cmd); } int transport_generic_handle_tmr( @@ -3338,11 +3347,10 @@ int transport_generic_handle_tmr( spin_unlock_irqrestore(&cmd->t_state_lock, flags); if (aborted) { - pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d" - "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function, - cmd->se_tmr_req->ref_task_tag, cmd->tag); - transport_lun_remove_cmd(cmd); - transport_cmd_check_stop_to_fabric(cmd); + pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n", + cmd->se_tmr_req->function, + cmd->se_tmr_req->ref_task_tag, cmd->tag); + target_handle_abort(cmd); return 0; } |