From 3dff5721e4f67e6231dfc419d30aaa7563bfffd4 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 28 Nov 2011 12:08:22 -0800 Subject: [SCSI] libsas: close error handling vs sas_ata_task_done() race Since sas_ata does not implement ->freeze(), completions for scmds and internal commands can still arrive concurrent with ata_scsi_cmd_error_handler() and sas_ata_post_internal() respectively. By the time either of those is called libata has committed to completing the qc, and the ATA_PFLAG_FROZEN flag tells sas_ata_task_done() it has lost the race. In the sas_ata_post_internal() case we take on the additional responsibility of freeing the sas_task to close the race with sas_ata_task_done() freeing the the task while sas_ata_post_internal() is in the process of invoking ->lldd_abort_task(). Signed-off-by: Dan Williams Signed-off-by: James Bottomley --- drivers/scsi/libsas/sas_scsi_host.c | 44 ------------------------------------- 1 file changed, 44 deletions(-) (limited to 'drivers/scsi/libsas/sas_scsi_host.c') diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c index 15533a17eb97..ba5876ccd29a 100644 --- a/drivers/scsi/libsas/sas_scsi_host.c +++ b/drivers/scsi/libsas/sas_scsi_host.c @@ -956,49 +956,6 @@ void sas_shutdown_queue(struct sas_ha_struct *sas_ha) spin_unlock_irqrestore(&core->task_queue_lock, flags); } -/* - * Call the LLDD task abort routine directly. This function is intended for - * use by upper layers that need to tell the LLDD to abort a task. - */ -int __sas_task_abort(struct sas_task *task) -{ - struct sas_internal *si = - to_sas_internal(task->dev->port->ha->core.shost->transportt); - unsigned long flags; - int res; - - spin_lock_irqsave(&task->task_state_lock, flags); - if (task->task_state_flags & SAS_TASK_STATE_ABORTED || - task->task_state_flags & SAS_TASK_STATE_DONE) { - spin_unlock_irqrestore(&task->task_state_lock, flags); - SAS_DPRINTK("%s: Task %p already finished.\n", __func__, - task); - return 0; - } - task->task_state_flags |= SAS_TASK_STATE_ABORTED; - spin_unlock_irqrestore(&task->task_state_lock, flags); - - if (!si->dft->lldd_abort_task) - return -ENODEV; - - res = si->dft->lldd_abort_task(task); - - spin_lock_irqsave(&task->task_state_lock, flags); - if ((task->task_state_flags & SAS_TASK_STATE_DONE) || - (res == TMF_RESP_FUNC_COMPLETE)) - { - spin_unlock_irqrestore(&task->task_state_lock, flags); - task->task_done(task); - return 0; - } - - if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) - task->task_state_flags &= ~SAS_TASK_STATE_ABORTED; - spin_unlock_irqrestore(&task->task_state_lock, flags); - - return -EAGAIN; -} - /* * Tell an upper layer that it needs to initiate an abort for a given task. * This should only ever be called by an LLDD. @@ -1097,7 +1054,6 @@ EXPORT_SYMBOL_GPL(sas_slave_configure); EXPORT_SYMBOL_GPL(sas_change_queue_depth); EXPORT_SYMBOL_GPL(sas_change_queue_type); EXPORT_SYMBOL_GPL(sas_bios_param); -EXPORT_SYMBOL_GPL(__sas_task_abort); EXPORT_SYMBOL_GPL(sas_task_abort); EXPORT_SYMBOL_GPL(sas_phy_reset); EXPORT_SYMBOL_GPL(sas_phy_enable); -- cgit v1.2.1