linux/drivers/scsi/libsas/sas_event.c
Dan Williams 303694eeee [SCSI] libsas: suspend / resume support
libsas power management routines to suspend and recover the sas domain
based on a model where the lldd is allowed and expected to be
"forgetful".

sas_suspend_ha - disable event processing allowing the lldd to take down
                 links without concern for causing hotplug events.
                 Regardless of whether the lldd actually posts link down
                 messages libsas notifies the lldd that all
                 domain_devices are gone.

sas_prep_resume_ha - on the way back up before the lldd starts link
                     training clean out any spurious events that were
                     generated on the way down, and re-enable event
                     processing

sas_resume_ha - after the lldd has started and decided that all phys
		have posted link-up events this routine is called to let
		libsas start it's own timeout of any phys that did not
		resume.  After the timeout an lldd can cancel the
                phy teardown by posting a link-up event.

Storage for ex_change_count (u16) and phy_change_count (u8) are changed
to int so they can be set to -1 to indicate 'invalidated'.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Tested-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-08-24 13:10:23 +04:00

166 lines
4.2 KiB
C

/*
* Serial Attached SCSI (SAS) Event processing
*
* Copyright (C) 2005 Adaptec, Inc. All rights reserved.
* Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
*
* This file is licensed under GPLv2.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <linux/export.h>
#include <scsi/scsi_host.h>
#include "sas_internal.h"
#include "sas_dump.h"
void sas_queue_work(struct sas_ha_struct *ha, struct sas_work *sw)
{
if (!test_bit(SAS_HA_REGISTERED, &ha->state))
return;
if (test_bit(SAS_HA_DRAINING, &ha->state)) {
/* add it to the defer list, if not already pending */
if (list_empty(&sw->drain_node))
list_add(&sw->drain_node, &ha->defer_q);
} else
scsi_queue_work(ha->core.shost, &sw->work);
}
static void sas_queue_event(int event, unsigned long *pending,
struct sas_work *work,
struct sas_ha_struct *ha)
{
if (!test_and_set_bit(event, pending)) {
unsigned long flags;
spin_lock_irqsave(&ha->lock, flags);
sas_queue_work(ha, work);
spin_unlock_irqrestore(&ha->lock, flags);
}
}
void __sas_drain_work(struct sas_ha_struct *ha)
{
struct workqueue_struct *wq = ha->core.shost->work_q;
struct sas_work *sw, *_sw;
set_bit(SAS_HA_DRAINING, &ha->state);
/* flush submitters */
spin_lock_irq(&ha->lock);
spin_unlock_irq(&ha->lock);
drain_workqueue(wq);
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->lock);
}
int sas_drain_work(struct sas_ha_struct *ha)
{
int err;
err = mutex_lock_interruptible(&ha->drain_mutex);
if (err)
return err;
if (test_bit(SAS_HA_REGISTERED, &ha->state))
__sas_drain_work(ha);
mutex_unlock(&ha->drain_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(sas_drain_work);
void sas_disable_revalidation(struct sas_ha_struct *ha)
{
mutex_lock(&ha->disco_mutex);
set_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state);
mutex_unlock(&ha->disco_mutex);
}
void sas_enable_revalidation(struct sas_ha_struct *ha)
{
int i;
mutex_lock(&ha->disco_mutex);
clear_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state);
for (i = 0; i < ha->num_phys; i++) {
struct asd_sas_port *port = ha->sas_port[i];
const int ev = DISCE_REVALIDATE_DOMAIN;
struct sas_discovery *d = &port->disc;
if (!test_and_clear_bit(ev, &d->pending))
continue;
sas_queue_event(ev, &d->pending, &d->disc_work[ev].work, ha);
}
mutex_unlock(&ha->disco_mutex);
}
static void notify_ha_event(struct sas_ha_struct *sas_ha, enum ha_event event)
{
BUG_ON(event >= HA_NUM_EVENTS);
sas_queue_event(event, &sas_ha->pending,
&sas_ha->ha_events[event].work, sas_ha);
}
static void notify_port_event(struct asd_sas_phy *phy, enum port_event event)
{
struct sas_ha_struct *ha = phy->ha;
BUG_ON(event >= PORT_NUM_EVENTS);
sas_queue_event(event, &phy->port_events_pending,
&phy->port_events[event].work, ha);
}
void sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event)
{
struct sas_ha_struct *ha = phy->ha;
BUG_ON(event >= PHY_NUM_EVENTS);
sas_queue_event(event, &phy->phy_events_pending,
&phy->phy_events[event].work, ha);
}
int sas_init_events(struct sas_ha_struct *sas_ha)
{
static const work_func_t sas_ha_event_fns[HA_NUM_EVENTS] = {
[HAE_RESET] = sas_hae_reset,
};
int i;
for (i = 0; i < HA_NUM_EVENTS; i++) {
INIT_SAS_WORK(&sas_ha->ha_events[i].work, sas_ha_event_fns[i]);
sas_ha->ha_events[i].ha = sas_ha;
}
sas_ha->notify_ha_event = notify_ha_event;
sas_ha->notify_port_event = notify_port_event;
sas_ha->notify_phy_event = sas_notify_phy_event;
return 0;
}