alistair23-linux/drivers/scsi/libsas/sas_phy.c
Jason Yan f12486e06a scsi: libsas: shut down the PHY if events reached the threshold
If the PHY burst too many events, we will alloc a lot of events for the
worker. This may leads to memory exhaustion.

Dan Williams suggested to shut down the PHY if the events reached the
threshold, because in this case the PHY may have gone into some
erroneous state. Users can re-enable the PHY by sysfs if they want.

We cannot use the fixed memory pool because if we run out of events, the
shut down event and loss of signal event will lost too. The events still
need to be allocated and processed in this case.

Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: John Garry <john.garry@huawei.com>
CC: Johannes Thumshirn <jthumshirn@suse.de>
CC: Ewan Milne <emilne@redhat.com>
CC: Christoph Hellwig <hch@lst.de>
CC: Tomas Henzl <thenzl@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-01-08 21:59:28 -05:00

181 lines
4.8 KiB
C

/*
* Serial Attached SCSI (SAS) Phy class
*
* 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 "sas_internal.h"
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include "../scsi_sas_internal.h"
/* ---------- Phy events ---------- */
static void sas_phye_loss_of_signal(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
phy->in_shutdown = 0;
phy->error = 0;
sas_deform_port(phy, 1);
}
static void sas_phye_oob_done(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
phy->in_shutdown = 0;
phy->error = 0;
}
static void sas_phye_oob_error(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
struct sas_ha_struct *sas_ha = phy->ha;
struct asd_sas_port *port = phy->port;
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
sas_deform_port(phy, 1);
if (!port && phy->enabled && i->dft->lldd_control_phy) {
phy->error++;
switch (phy->error) {
case 1:
case 2:
i->dft->lldd_control_phy(phy, PHY_FUNC_HARD_RESET,
NULL);
break;
case 3:
default:
phy->error = 0;
phy->enabled = 0;
i->dft->lldd_control_phy(phy, PHY_FUNC_DISABLE, NULL);
break;
}
}
}
static void sas_phye_spinup_hold(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
struct sas_ha_struct *sas_ha = phy->ha;
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
phy->error = 0;
i->dft->lldd_control_phy(phy, PHY_FUNC_RELEASE_SPINUP_HOLD, NULL);
}
static void sas_phye_resume_timeout(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
/* phew, lldd got the phy back in the nick of time */
if (!phy->suspended) {
dev_info(&phy->phy->dev, "resume timeout cancelled\n");
return;
}
phy->error = 0;
phy->suspended = 0;
sas_deform_port(phy, 1);
}
static void sas_phye_shutdown(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
struct sas_ha_struct *sas_ha = phy->ha;
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
if (phy->enabled) {
int ret;
phy->error = 0;
phy->enabled = 0;
ret = i->dft->lldd_control_phy(phy, PHY_FUNC_DISABLE, NULL);
if (ret)
sas_printk("lldd disable phy%02d returned %d\n",
phy->id, ret);
} else
sas_printk("phy%02d is not enabled, cannot shutdown\n",
phy->id);
}
/* ---------- Phy class registration ---------- */
int sas_register_phys(struct sas_ha_struct *sas_ha)
{
int i;
/* Now register the phys. */
for (i = 0; i < sas_ha->num_phys; i++) {
struct asd_sas_phy *phy = sas_ha->sas_phy[i];
phy->error = 0;
atomic_set(&phy->event_nr, 0);
INIT_LIST_HEAD(&phy->port_phy_el);
phy->port = NULL;
phy->ha = sas_ha;
spin_lock_init(&phy->frame_rcvd_lock);
spin_lock_init(&phy->sas_prim_lock);
phy->frame_rcvd_size = 0;
phy->phy = sas_phy_alloc(&sas_ha->core.shost->shost_gendev, i);
if (!phy->phy)
return -ENOMEM;
phy->phy->identify.initiator_port_protocols =
phy->iproto;
phy->phy->identify.target_port_protocols = phy->tproto;
phy->phy->identify.sas_address = SAS_ADDR(sas_ha->sas_addr);
phy->phy->identify.phy_identifier = i;
phy->phy->minimum_linkrate_hw = SAS_LINK_RATE_UNKNOWN;
phy->phy->maximum_linkrate_hw = SAS_LINK_RATE_UNKNOWN;
phy->phy->minimum_linkrate = SAS_LINK_RATE_UNKNOWN;
phy->phy->maximum_linkrate = SAS_LINK_RATE_UNKNOWN;
phy->phy->negotiated_linkrate = SAS_LINK_RATE_UNKNOWN;
sas_phy_add(phy->phy);
}
return 0;
}
const work_func_t sas_phy_event_fns[PHY_NUM_EVENTS] = {
[PHYE_LOSS_OF_SIGNAL] = sas_phye_loss_of_signal,
[PHYE_OOB_DONE] = sas_phye_oob_done,
[PHYE_OOB_ERROR] = sas_phye_oob_error,
[PHYE_SPINUP_HOLD] = sas_phye_spinup_hold,
[PHYE_RESUME_TIMEOUT] = sas_phye_resume_timeout,
[PHYE_SHUTDOWN] = sas_phye_shutdown,
};