From f147abb475ab47ce620cf3d18de5b3192c9fa7ed Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Tue, 25 Oct 2011 23:57:41 -0700 Subject: [PATCH] target: Check -ENOMEM to signal QUEUE_FULL from fabric callbacks This patch changes target core to also check for -ENOMEM from fabric callbacks to signal QUEUE_FULL status, instead of just -EAGAIN in order to catch a larger set of fabric failure cases that want to trigger QUEUE_FULL logic. This includes the callbacks for ->write_pending(), ->queue_data_in() and ->queue_status(). It also makes transport_generic_write_pending() return zero upon QUEUE_FULL, and removes two unnecessary -EAGAIN checks to catch write pending QUEUE_FULL cases from transport_generic_new_cmd() failures in transport_handle_cdb_direct() and transport_processing_thread():TRANSPORT_NEW_CMD_MAP state. Reported-by: Bart Van Assche Cc: Bart Van Assche Cc: Christoph Hellwig Cc: Roland Dreier Signed-off-by: Nicholas A. Bellinger --- drivers/target/target_core_transport.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index d752558..5dee446 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -908,7 +908,7 @@ void transport_remove_task_from_execute_queue( } /* - * Handle QUEUE_FULL / -EAGAIN status + * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status */ static void target_qf_do_work(struct work_struct *work) @@ -1645,9 +1645,7 @@ int transport_handle_cdb_direct( * and call transport_generic_request_failure() if necessary.. */ ret = transport_generic_new_cmd(cmd); - if (ret == -EAGAIN) - return 0; - else if (ret < 0) { + if (ret < 0) { cmd->transport_error_status = ret; transport_generic_request_failure(cmd, 0, (cmd->data_direction != DMA_TO_DEVICE)); @@ -1886,7 +1884,7 @@ static void transport_generic_request_failure( ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS); ret = cmd->se_tfo->queue_status(cmd); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; goto check_stop; case PYX_TRANSPORT_USE_SENSE_REASON: @@ -1913,7 +1911,7 @@ static void transport_generic_request_failure( else { ret = transport_send_check_condition_and_sense(cmd, cmd->scsi_sense_reason, 0); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; } @@ -3308,7 +3306,7 @@ static void target_complete_ok_work(struct work_struct *work) if (cmd->scsi_status) { ret = transport_send_check_condition_and_sense( cmd, reason, 1); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; transport_lun_remove_cmd(cmd); @@ -3333,7 +3331,7 @@ static void target_complete_ok_work(struct work_struct *work) spin_unlock(&cmd->se_lun->lun_sep_lock); ret = cmd->se_tfo->queue_data_in(cmd); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; break; case DMA_TO_DEVICE: @@ -3354,14 +3352,14 @@ static void target_complete_ok_work(struct work_struct *work) } spin_unlock(&cmd->se_lun->lun_sep_lock); ret = cmd->se_tfo->queue_data_in(cmd); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; break; } /* Fall through for DMA_TO_DEVICE */ case DMA_NONE: ret = cmd->se_tfo->queue_status(cmd); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; break; default: @@ -3890,7 +3888,10 @@ EXPORT_SYMBOL(transport_generic_process_write); static void transport_write_pending_qf(struct se_cmd *cmd) { - if (cmd->se_tfo->write_pending(cmd) == -EAGAIN) { + int ret; + + ret = cmd->se_tfo->write_pending(cmd); + if (ret == -EAGAIN || ret == -ENOMEM) { pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd); transport_handle_queue_full(cmd, cmd->se_dev); @@ -3920,7 +3921,7 @@ static int transport_generic_write_pending(struct se_cmd *cmd) * frontend know that WRITE buffers are ready. */ ret = cmd->se_tfo->write_pending(cmd); - if (ret == -EAGAIN) + if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; else if (ret < 0) return ret; @@ -3931,7 +3932,7 @@ queue_full: pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd); cmd->t_state = TRANSPORT_COMPLETE_QF_WP; transport_handle_queue_full(cmd, cmd->se_dev); - return ret; + return 0; } /** @@ -4583,9 +4584,7 @@ get_cmd: break; } ret = transport_generic_new_cmd(cmd); - if (ret == -EAGAIN) - break; - else if (ret < 0) { + if (ret < 0) { cmd->transport_error_status = ret; transport_generic_request_failure(cmd, 0, (cmd->data_direction != -- 2.7.4