[SCSI] libata, libsas: introduce sched_eh and end_eh port ops
When managing shost->host_eh_scheduled libata assumes that there is a
1:1 shost-to-ata_port relationship. libsas creates a 1:N relationship
so it needs to manage host_eh_scheduled cumulatively at the host level.
The sched_eh and end_eh port port ops allow libsas to track when domain
devices enter/leave the "eh-pending" state under ha->lock (previously
named ha->state_lock, but it is no longer just a lock for ha->state
changes).
Since host_eh_scheduled indicates eh without backing commands pinning
the device it can be deallocated at any time. Move the taking of the
domain_device reference under the port_lock to guarantee that the
ata_port stays around for the duration of eh.
Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index d109cc3..b035acf 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -523,6 +523,31 @@
i->dft->lldd_ata_set_dmamode(dev);
}
+static void sas_ata_sched_eh(struct ata_port *ap)
+{
+ struct domain_device *dev = ap->private_data;
+ struct sas_ha_struct *ha = dev->port->ha;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ha->lock, flags);
+ if (!test_and_set_bit(SAS_DEV_EH_PENDING, &dev->state))
+ ha->eh_active++;
+ ata_std_sched_eh(ap);
+ spin_unlock_irqrestore(&ha->lock, flags);
+}
+
+void sas_ata_end_eh(struct ata_port *ap)
+{
+ struct domain_device *dev = ap->private_data;
+ struct sas_ha_struct *ha = dev->port->ha;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ha->lock, flags);
+ if (test_and_clear_bit(SAS_DEV_EH_PENDING, &dev->state))
+ ha->eh_active--;
+ spin_unlock_irqrestore(&ha->lock, flags);
+}
+
static struct ata_port_operations sas_sata_ops = {
.prereset = ata_std_prereset,
.hardreset = sas_ata_hard_reset,
@@ -536,6 +561,8 @@
.port_start = ata_sas_port_start,
.port_stop = ata_sas_port_stop,
.set_dmamode = sas_ata_set_dmamode,
+ .sched_eh = sas_ata_sched_eh,
+ .end_eh = sas_ata_end_eh,
};
static struct ata_port_info sata_port_info = {
@@ -708,10 +735,6 @@
struct ata_port *ap = dev->sata_dev.ap;
struct sas_ha_struct *ha = dev->port->ha;
- /* hold a reference over eh since we may be racing with final
- * remove once all commands are completed
- */
- kref_get(&dev->kref);
sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
ata_scsi_port_error_handler(ha->core.shost, ap);
sas_put_device(dev);
@@ -742,6 +765,13 @@
list_for_each_entry(dev, &port->dev_list, dev_list_node) {
if (!dev_is_sata(dev))
continue;
+
+ /* hold a reference over eh since we may be
+ * racing with final remove once all commands
+ * are completed
+ */
+ kref_get(&dev->kref);
+
async_schedule_domain(async_sas_ata_eh, dev, &async);
}
spin_unlock(&port->dev_list_lock);
diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
index 629a086..ff497ac 100644
--- a/drivers/scsi/libsas/sas_discover.c
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -294,6 +294,8 @@
spin_lock_irq(&port->dev_list_lock);
list_del_init(&dev->dev_list_node);
+ if (dev_is_sata(dev))
+ sas_ata_end_eh(dev->sata_dev.ap);
spin_unlock_irq(&port->dev_list_lock);
sas_put_device(dev);
@@ -488,9 +490,9 @@
if (!test_and_set_bit(event, pending)) {
unsigned long flags;
- spin_lock_irqsave(&ha->state_lock, flags);
+ spin_lock_irqsave(&ha->lock, flags);
sas_chain_work(ha, sw);
- spin_unlock_irqrestore(&ha->state_lock, flags);
+ spin_unlock_irqrestore(&ha->lock, flags);
}
}
diff --git a/drivers/scsi/libsas/sas_event.c b/drivers/scsi/libsas/sas_event.c
index 4e4292d..789c4d8 100644
--- a/drivers/scsi/libsas/sas_event.c
+++ b/drivers/scsi/libsas/sas_event.c
@@ -47,9 +47,9 @@
if (!test_and_set_bit(event, pending)) {
unsigned long flags;
- spin_lock_irqsave(&ha->state_lock, flags);
+ spin_lock_irqsave(&ha->lock, flags);
sas_queue_work(ha, work);
- spin_unlock_irqrestore(&ha->state_lock, flags);
+ spin_unlock_irqrestore(&ha->lock, flags);
}
}
@@ -61,18 +61,18 @@
set_bit(SAS_HA_DRAINING, &ha->state);
/* flush submitters */
- spin_lock_irq(&ha->state_lock);
- spin_unlock_irq(&ha->state_lock);
+ spin_lock_irq(&ha->lock);
+ spin_unlock_irq(&ha->lock);
drain_workqueue(wq);
- spin_lock_irq(&ha->state_lock);
+ spin_lock_irq(&ha->lock);
clear_bit(SAS_HA_DRAINING, &ha->state);
list_for_each_entry_safe(sw, _sw, &ha->defer_q, drain_node) {
list_del_init(&sw->drain_node);
sas_queue_work(ha, sw);
}
- spin_unlock_irq(&ha->state_lock);
+ spin_unlock_irq(&ha->lock);
}
int sas_drain_work(struct sas_ha_struct *ha)
diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
index 10cb5ae3..6909fef 100644
--- a/drivers/scsi/libsas/sas_init.c
+++ b/drivers/scsi/libsas/sas_init.c
@@ -114,7 +114,7 @@
sas_ha->lldd_queue_size = 128; /* Sanity */
set_bit(SAS_HA_REGISTERED, &sas_ha->state);
- spin_lock_init(&sas_ha->state_lock);
+ spin_lock_init(&sas_ha->lock);
mutex_init(&sas_ha->drain_mutex);
INIT_LIST_HEAD(&sas_ha->defer_q);
@@ -163,9 +163,9 @@
* events to be queued, and flush any in-progress drainers
*/
mutex_lock(&sas_ha->drain_mutex);
- spin_lock_irq(&sas_ha->state_lock);
+ spin_lock_irq(&sas_ha->lock);
clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
- spin_unlock_irq(&sas_ha->state_lock);
+ spin_unlock_irq(&sas_ha->lock);
__sas_drain_work(sas_ha);
mutex_unlock(&sas_ha->drain_mutex);
@@ -411,9 +411,9 @@
d->reset_result = 0;
d->hard_reset = hard_reset;
- spin_lock_irq(&ha->state_lock);
+ spin_lock_irq(&ha->lock);
sas_queue_work(ha, &d->reset_work);
- spin_unlock_irq(&ha->state_lock);
+ spin_unlock_irq(&ha->lock);
rc = sas_drain_work(ha);
if (rc == 0)
@@ -438,9 +438,9 @@
d->enable_result = 0;
d->enable = enable;
- spin_lock_irq(&ha->state_lock);
+ spin_lock_irq(&ha->lock);
sas_queue_work(ha, &d->enable_work);
- spin_unlock_irq(&ha->state_lock);
+ spin_unlock_irq(&ha->lock);
rc = sas_drain_work(ha);
if (rc == 0)
diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c
index f0b9b7b..a09da44 100644
--- a/drivers/scsi/libsas/sas_scsi_host.c
+++ b/drivers/scsi/libsas/sas_scsi_host.c
@@ -667,16 +667,20 @@
goto out;
}
+
void sas_scsi_recover_host(struct Scsi_Host *shost)
{
struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
- unsigned long flags;
LIST_HEAD(eh_work_q);
+ int tries = 0;
+ bool retry;
- spin_lock_irqsave(shost->host_lock, flags);
+retry:
+ tries++;
+ retry = true;
+ spin_lock_irq(shost->host_lock);
list_splice_init(&shost->eh_cmd_q, &eh_work_q);
- shost->host_eh_scheduled = 0;
- spin_unlock_irqrestore(shost->host_lock, flags);
+ spin_unlock_irq(shost->host_lock);
SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
__func__, shost->host_busy, shost->host_failed);
@@ -710,8 +714,19 @@
scsi_eh_flush_done_q(&ha->eh_done_q);
- SAS_DPRINTK("--- Exit %s: busy: %d failed: %d\n",
- __func__, shost->host_busy, shost->host_failed);
+ /* check if any new eh work was scheduled during the last run */
+ spin_lock_irq(&ha->lock);
+ if (ha->eh_active == 0) {
+ shost->host_eh_scheduled = 0;
+ retry = false;
+ }
+ spin_unlock_irq(&ha->lock);
+
+ if (retry)
+ goto retry;
+
+ SAS_DPRINTK("--- Exit %s: busy: %d failed: %d tries: %d\n",
+ __func__, shost->host_busy, shost->host_failed, tries);
}
enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)