linux-stable/drivers/scsi/libsas/sas_port.c
Jason Yan 1c393b970e scsi: libsas: Use dynamic alloced work to avoid sas event lost
Now libsas hotplug work is static, every sas event type has its own
static work, LLDD driver queues the hotplug work into shost->work_q.  If
LLDD driver burst posts lots hotplug events to libsas, the hotplug
events may pending in the workqueue like

shost->work_q
new work[PORTE_BYTES_DMAED] --> |[PHYE_LOSS_OF_SIGNAL][PORTE_BYTES_DMAED] -> processing
                                |<-------wait worker to process-------->|

In this case, a new PORTE_BYTES_DMAED event coming, libsas try to queue
it to shost->work_q, but this work is already pending, so it would be
lost. Finally, libsas delete the related sas port and sas devices, but
LLDD driver expect libsas add the sas port and devices(last sas event).

This patch use dynamic allocated work to avoid this issue.

Signed-off-by: Yijing Wang <wangyijing@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>
CC: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-01-08 21:59:28 -05:00

353 lines
9.3 KiB
C

/*
* Serial Attached SCSI (SAS) Port 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_transport.h>
#include <scsi/scsi_transport_sas.h>
#include "../scsi_sas_internal.h"
static bool phy_is_wideport_member(struct asd_sas_port *port, struct asd_sas_phy *phy)
{
struct sas_ha_struct *sas_ha = phy->ha;
if (memcmp(port->attached_sas_addr, phy->attached_sas_addr,
SAS_ADDR_SIZE) != 0 || (sas_ha->strict_wide_ports &&
memcmp(port->sas_addr, phy->sas_addr, SAS_ADDR_SIZE) != 0))
return false;
return true;
}
static void sas_resume_port(struct asd_sas_phy *phy)
{
struct domain_device *dev;
struct asd_sas_port *port = phy->port;
struct sas_ha_struct *sas_ha = phy->ha;
struct sas_internal *si = to_sas_internal(sas_ha->core.shost->transportt);
if (si->dft->lldd_port_formed)
si->dft->lldd_port_formed(phy);
if (port->suspended)
port->suspended = 0;
else {
/* we only need to handle "link returned" actions once */
return;
}
/* if the port came back:
* 1/ presume every device came back
* 2/ force the next revalidation to check all expander phys
*/
list_for_each_entry(dev, &port->dev_list, dev_list_node) {
int i, rc;
rc = sas_notify_lldd_dev_found(dev);
if (rc) {
sas_unregister_dev(port, dev);
continue;
}
if (dev->dev_type == SAS_EDGE_EXPANDER_DEVICE || dev->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
dev->ex_dev.ex_change_count = -1;
for (i = 0; i < dev->ex_dev.num_phys; i++) {
struct ex_phy *phy = &dev->ex_dev.ex_phy[i];
phy->phy_change_count = -1;
}
}
}
sas_discover_event(port, DISCE_RESUME);
}
/**
* sas_form_port -- add this phy to a port
* @phy: the phy of interest
*
* This function adds this phy to an existing port, thus creating a wide
* port, or it creates a port and adds the phy to the port.
*/
static void sas_form_port(struct asd_sas_phy *phy)
{
int i;
struct sas_ha_struct *sas_ha = phy->ha;
struct asd_sas_port *port = phy->port;
struct sas_internal *si =
to_sas_internal(sas_ha->core.shost->transportt);
unsigned long flags;
if (port) {
if (!phy_is_wideport_member(port, phy))
sas_deform_port(phy, 0);
else if (phy->suspended) {
phy->suspended = 0;
sas_resume_port(phy);
/* phy came back, try to cancel the timeout */
wake_up(&sas_ha->eh_wait_q);
return;
} else {
SAS_DPRINTK("%s: phy%d belongs to port%d already(%d)!\n",
__func__, phy->id, phy->port->id,
phy->port->num_phys);
return;
}
}
/* see if the phy should be part of a wide port */
spin_lock_irqsave(&sas_ha->phy_port_lock, flags);
for (i = 0; i < sas_ha->num_phys; i++) {
port = sas_ha->sas_port[i];
spin_lock(&port->phy_list_lock);
if (*(u64 *) port->sas_addr &&
phy_is_wideport_member(port, phy) && port->num_phys > 0) {
/* wide port */
SAS_DPRINTK("phy%d matched wide port%d\n", phy->id,
port->id);
break;
}
spin_unlock(&port->phy_list_lock);
}
/* The phy does not match any existing port, create a new one */
if (i == sas_ha->num_phys) {
for (i = 0; i < sas_ha->num_phys; i++) {
port = sas_ha->sas_port[i];
spin_lock(&port->phy_list_lock);
if (*(u64 *)port->sas_addr == 0
&& port->num_phys == 0) {
memcpy(port->sas_addr, phy->sas_addr,
SAS_ADDR_SIZE);
break;
}
spin_unlock(&port->phy_list_lock);
}
}
if (i >= sas_ha->num_phys) {
printk(KERN_NOTICE "%s: couldn't find a free port, bug?\n",
__func__);
spin_unlock_irqrestore(&sas_ha->phy_port_lock, flags);
return;
}
/* add the phy to the port */
list_add_tail(&phy->port_phy_el, &port->phy_list);
sas_phy_set_target(phy, port->port_dev);
phy->port = port;
port->num_phys++;
port->phy_mask |= (1U << phy->id);
if (*(u64 *)port->attached_sas_addr == 0) {
port->class = phy->class;
memcpy(port->attached_sas_addr, phy->attached_sas_addr,
SAS_ADDR_SIZE);
port->iproto = phy->iproto;
port->tproto = phy->tproto;
port->oob_mode = phy->oob_mode;
port->linkrate = phy->linkrate;
} else
port->linkrate = max(port->linkrate, phy->linkrate);
spin_unlock(&port->phy_list_lock);
spin_unlock_irqrestore(&sas_ha->phy_port_lock, flags);
if (!port->port) {
port->port = sas_port_alloc(phy->phy->dev.parent, port->id);
BUG_ON(!port->port);
sas_port_add(port->port);
}
sas_port_add_phy(port->port, phy->phy);
SAS_DPRINTK("%s added to %s, phy_mask:0x%x (%16llx)\n",
dev_name(&phy->phy->dev), dev_name(&port->port->dev),
port->phy_mask,
SAS_ADDR(port->attached_sas_addr));
if (port->port_dev)
port->port_dev->pathways = port->num_phys;
/* Tell the LLDD about this port formation. */
if (si->dft->lldd_port_formed)
si->dft->lldd_port_formed(phy);
sas_discover_event(phy->port, DISCE_DISCOVER_DOMAIN);
}
/**
* sas_deform_port -- remove this phy from the port it belongs to
* @phy: the phy of interest
*
* This is called when the physical link to the other phy has been
* lost (on this phy), in Event thread context. We cannot delay here.
*/
void sas_deform_port(struct asd_sas_phy *phy, int gone)
{
struct sas_ha_struct *sas_ha = phy->ha;
struct asd_sas_port *port = phy->port;
struct sas_internal *si =
to_sas_internal(sas_ha->core.shost->transportt);
struct domain_device *dev;
unsigned long flags;
if (!port)
return; /* done by a phy event */
dev = port->port_dev;
if (dev)
dev->pathways--;
if (port->num_phys == 1) {
sas_unregister_domain_devices(port, gone);
sas_port_delete(port->port);
port->port = NULL;
} else {
sas_port_delete_phy(port->port, phy->phy);
sas_device_set_phy(dev, port->port);
}
if (si->dft->lldd_port_deformed)
si->dft->lldd_port_deformed(phy);
spin_lock_irqsave(&sas_ha->phy_port_lock, flags);
spin_lock(&port->phy_list_lock);
list_del_init(&phy->port_phy_el);
sas_phy_set_target(phy, NULL);
phy->port = NULL;
port->num_phys--;
port->phy_mask &= ~(1U << phy->id);
if (port->num_phys == 0) {
INIT_LIST_HEAD(&port->phy_list);
memset(port->sas_addr, 0, SAS_ADDR_SIZE);
memset(port->attached_sas_addr, 0, SAS_ADDR_SIZE);
port->class = 0;
port->iproto = 0;
port->tproto = 0;
port->oob_mode = 0;
port->phy_mask = 0;
}
spin_unlock(&port->phy_list_lock);
spin_unlock_irqrestore(&sas_ha->phy_port_lock, flags);
return;
}
/* ---------- SAS port events ---------- */
void sas_porte_bytes_dmaed(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
sas_form_port(phy);
}
void sas_porte_broadcast_rcvd(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
unsigned long flags;
u32 prim;
spin_lock_irqsave(&phy->sas_prim_lock, flags);
prim = phy->sas_prim;
spin_unlock_irqrestore(&phy->sas_prim_lock, flags);
SAS_DPRINTK("broadcast received: %d\n", prim);
sas_discover_event(phy->port, DISCE_REVALIDATE_DOMAIN);
}
void sas_porte_link_reset_err(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
sas_deform_port(phy, 1);
}
void sas_porte_timer_event(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
sas_deform_port(phy, 1);
}
void sas_porte_hard_reset(struct work_struct *work)
{
struct asd_sas_event *ev = to_asd_sas_event(work);
struct asd_sas_phy *phy = ev->phy;
sas_deform_port(phy, 1);
}
/* ---------- SAS port registration ---------- */
static void sas_init_port(struct asd_sas_port *port,
struct sas_ha_struct *sas_ha, int i)
{
memset(port, 0, sizeof(*port));
port->id = i;
INIT_LIST_HEAD(&port->dev_list);
INIT_LIST_HEAD(&port->disco_list);
INIT_LIST_HEAD(&port->destroy_list);
spin_lock_init(&port->phy_list_lock);
INIT_LIST_HEAD(&port->phy_list);
port->ha = sas_ha;
spin_lock_init(&port->dev_list_lock);
}
int sas_register_ports(struct sas_ha_struct *sas_ha)
{
int i;
/* initialize the ports and discovery */
for (i = 0; i < sas_ha->num_phys; i++) {
struct asd_sas_port *port = sas_ha->sas_port[i];
sas_init_port(port, sas_ha, i);
sas_init_disc(&port->disc, port);
}
return 0;
}
void sas_unregister_ports(struct sas_ha_struct *sas_ha)
{
int i;
for (i = 0; i < sas_ha->num_phys; i++)
if (sas_ha->sas_phy[i]->port)
sas_deform_port(sas_ha->sas_phy[i], 0);
}
const work_func_t sas_port_event_fns[PORT_NUM_EVENTS] = {
[PORTE_BYTES_DMAED] = sas_porte_bytes_dmaed,
[PORTE_BROADCAST_RCVD] = sas_porte_broadcast_rcvd,
[PORTE_LINK_RESET_ERR] = sas_porte_link_reset_err,
[PORTE_TIMER_EVENT] = sas_porte_timer_event,
[PORTE_HARD_RESET] = sas_porte_hard_reset,
};