From 312d3e56119a4bc5c36a96818f87f650c069ddc2 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 17 Nov 2011 17:59:50 -0800 Subject: [SCSI] libsas: remove ata_port.lock management duties from lldds Each libsas driver (mvsas, pm8001, and isci) has invented a different method for managing the ap->lock. The lock is held by the ata ->queuecommand() path. mvsas drops it prior to acquiring any internal locks which allows it to hold its internal lock across calls to task->task_done(). This capability is important as it is the only way the driver can flush task->task_done() instances to guarantee that it no longer has any in-flight references to a domain_device at ->lldd_dev_gone() time. Signed-off-by: Dan Williams Signed-off-by: James Bottomley --- drivers/scsi/libsas/sas_ata.c | 36 +++++++++++++++++++++++------------- 1 file changed, 23 insertions(+), 13 deletions(-) (limited to 'drivers/scsi/libsas/sas_ata.c') diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c index 83118d0b6d0c..81ce39d166d1 100644 --- a/drivers/scsi/libsas/sas_ata.c +++ b/drivers/scsi/libsas/sas_ata.c @@ -166,23 +166,30 @@ qc_already_gone: static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) { - int res; + unsigned long flags; struct sas_task *task; - struct domain_device *dev = qc->ap->private_data; + struct scatterlist *sg; + int ret = AC_ERR_SYSTEM; + unsigned int si, xfer = 0; + struct ata_port *ap = qc->ap; + struct domain_device *dev = ap->private_data; struct sas_ha_struct *sas_ha = dev->port->ha; struct Scsi_Host *host = sas_ha->core.shost; struct sas_internal *i = to_sas_internal(host->transportt); - struct scatterlist *sg; - unsigned int xfer = 0; - unsigned int si; + + /* TODO: audit callers to ensure they are ready for qc_issue to + * unconditionally re-enable interrupts + */ + local_irq_save(flags); + spin_unlock(ap->lock); /* If the device fell off, no sense in issuing commands */ if (dev->gone) - return AC_ERR_SYSTEM; + goto out; task = sas_alloc_task(GFP_ATOMIC); if (!task) - return AC_ERR_SYSTEM; + goto out; task->dev = dev; task->task_proto = SAS_PROTOCOL_STP; task->task_done = sas_ata_task_done; @@ -227,21 +234,24 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) ASSIGN_SAS_TASK(qc->scsicmd, task); if (sas_ha->lldd_max_execute_num < 2) - res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC); + ret = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC); else - res = sas_queue_up(task); + ret = sas_queue_up(task); /* Examine */ - if (res) { - SAS_DPRINTK("lldd_execute_task returned: %d\n", res); + if (ret) { + SAS_DPRINTK("lldd_execute_task returned: %d\n", ret); if (qc->scsicmd) ASSIGN_SAS_TASK(qc->scsicmd, NULL); sas_free_task(task); - return AC_ERR_SYSTEM; + ret = AC_ERR_SYSTEM; } - return 0; + out: + spin_lock(ap->lock); + local_irq_restore(flags); + return ret; } static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc) -- cgit v1.2.3