kernel_optimize_test/drivers/scsi/libsas/sas_init.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

623 lines
15 KiB
C

/*
* Serial Attached SCSI (SAS) Transport Layer initialization
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/spinlock.h>
#include <scsi/sas_ata.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include "sas_internal.h"
#include "../scsi_sas_internal.h"
static struct kmem_cache *sas_task_cache;
struct sas_task *sas_alloc_task(gfp_t flags)
{
struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
if (task) {
INIT_LIST_HEAD(&task->list);
spin_lock_init(&task->task_state_lock);
task->task_state_flags = SAS_TASK_STATE_PENDING;
}
return task;
}
EXPORT_SYMBOL_GPL(sas_alloc_task);
struct sas_task *sas_alloc_slow_task(gfp_t flags)
{
struct sas_task *task = sas_alloc_task(flags);
struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
if (!task || !slow) {
if (task)
kmem_cache_free(sas_task_cache, task);
kfree(slow);
return NULL;
}
task->slow_task = slow;
init_timer(&slow->timer);
init_completion(&slow->completion);
return task;
}
EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
void sas_free_task(struct sas_task *task)
{
if (task) {
BUG_ON(!list_empty(&task->list));
kfree(task->slow_task);
kmem_cache_free(sas_task_cache, task);
}
}
EXPORT_SYMBOL_GPL(sas_free_task);
/*------------ SAS addr hash -----------*/
void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
{
const u32 poly = 0x00DB2777;
u32 r = 0;
int i;
for (i = 0; i < 8; i++) {
int b;
for (b = 7; b >= 0; b--) {
r <<= 1;
if ((1 << b) & sas_addr[i]) {
if (!(r & 0x01000000))
r ^= poly;
} else if (r & 0x01000000)
r ^= poly;
}
}
hashed[0] = (r >> 16) & 0xFF;
hashed[1] = (r >> 8) & 0xFF ;
hashed[2] = r & 0xFF;
}
/* ---------- HA events ---------- */
void sas_hae_reset(struct work_struct *work)
{
struct sas_ha_event *ev = to_sas_ha_event(work);
struct sas_ha_struct *ha = ev->ha;
clear_bit(HAE_RESET, &ha->pending);
}
int sas_register_ha(struct sas_ha_struct *sas_ha)
{
int error = 0;
mutex_init(&sas_ha->disco_mutex);
spin_lock_init(&sas_ha->phy_port_lock);
sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
if (sas_ha->lldd_queue_size == 0)
sas_ha->lldd_queue_size = 1;
else if (sas_ha->lldd_queue_size == -1)
sas_ha->lldd_queue_size = 128; /* Sanity */
set_bit(SAS_HA_REGISTERED, &sas_ha->state);
spin_lock_init(&sas_ha->lock);
mutex_init(&sas_ha->drain_mutex);
init_waitqueue_head(&sas_ha->eh_wait_q);
INIT_LIST_HEAD(&sas_ha->defer_q);
INIT_LIST_HEAD(&sas_ha->eh_dev_q);
error = sas_register_phys(sas_ha);
if (error) {
printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
return error;
}
error = sas_register_ports(sas_ha);
if (error) {
printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
goto Undo_phys;
}
error = sas_init_events(sas_ha);
if (error) {
printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
goto Undo_ports;
}
if (sas_ha->lldd_max_execute_num > 1) {
error = sas_init_queue(sas_ha);
if (error) {
printk(KERN_NOTICE "couldn't start queue thread:%d, "
"running in direct mode\n", error);
sas_ha->lldd_max_execute_num = 1;
}
}
INIT_LIST_HEAD(&sas_ha->eh_done_q);
INIT_LIST_HEAD(&sas_ha->eh_ata_q);
return 0;
Undo_ports:
sas_unregister_ports(sas_ha);
Undo_phys:
return error;
}
static void sas_disable_events(struct sas_ha_struct *sas_ha)
{
/* Set the state to unregistered to avoid further unchained
* events to be queued, and flush any in-progress drainers
*/
mutex_lock(&sas_ha->drain_mutex);
spin_lock_irq(&sas_ha->lock);
clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
spin_unlock_irq(&sas_ha->lock);
__sas_drain_work(sas_ha);
mutex_unlock(&sas_ha->drain_mutex);
}
int sas_unregister_ha(struct sas_ha_struct *sas_ha)
{
sas_disable_events(sas_ha);
sas_unregister_ports(sas_ha);
/* flush unregistration work */
mutex_lock(&sas_ha->drain_mutex);
__sas_drain_work(sas_ha);
mutex_unlock(&sas_ha->drain_mutex);
if (sas_ha->lldd_max_execute_num > 1) {
sas_shutdown_queue(sas_ha);
sas_ha->lldd_max_execute_num = 1;
}
return 0;
}
static int sas_get_linkerrors(struct sas_phy *phy)
{
if (scsi_is_sas_phy_local(phy)) {
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
}
return sas_smp_get_phy_events(phy);
}
int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
{
struct domain_device *dev = NULL;
/* try to route user requested link resets through libata */
if (asd_phy->port)
dev = asd_phy->port->port_dev;
/* validate that dev has been probed */
if (dev)
dev = sas_find_dev_by_rphy(dev->rphy);
if (dev && dev_is_sata(dev)) {
sas_ata_schedule_reset(dev);
sas_ata_wait_eh(dev);
return 0;
}
return -ENODEV;
}
/**
* transport_sas_phy_reset - reset a phy and permit libata to manage the link
*
* phy reset request via sysfs in host workqueue context so we know we
* can block on eh and safely traverse the domain_device topology
*/
static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
{
enum phy_func reset_type;
if (hard_reset)
reset_type = PHY_FUNC_HARD_RESET;
else
reset_type = PHY_FUNC_LINK_RESET;
if (scsi_is_sas_phy_local(phy)) {
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
return 0;
return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
} else {
struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
if (ata_dev && !hard_reset) {
sas_ata_schedule_reset(ata_dev);
sas_ata_wait_eh(ata_dev);
return 0;
} else
return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
}
}
static int sas_phy_enable(struct sas_phy *phy, int enable)
{
int ret;
enum phy_func cmd;
if (enable)
cmd = PHY_FUNC_LINK_RESET;
else
cmd = PHY_FUNC_DISABLE;
if (scsi_is_sas_phy_local(phy)) {
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
if (enable)
ret = transport_sas_phy_reset(phy, 0);
else
ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
} else {
struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
if (enable)
ret = transport_sas_phy_reset(phy, 0);
else
ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
}
return ret;
}
int sas_phy_reset(struct sas_phy *phy, int hard_reset)
{
int ret;
enum phy_func reset_type;
if (!phy->enabled)
return -ENODEV;
if (hard_reset)
reset_type = PHY_FUNC_HARD_RESET;
else
reset_type = PHY_FUNC_LINK_RESET;
if (scsi_is_sas_phy_local(phy)) {
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
} else {
struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
}
return ret;
}
int sas_set_phy_speed(struct sas_phy *phy,
struct sas_phy_linkrates *rates)
{
int ret;
if ((rates->minimum_linkrate &&
rates->minimum_linkrate > phy->maximum_linkrate) ||
(rates->maximum_linkrate &&
rates->maximum_linkrate < phy->minimum_linkrate))
return -EINVAL;
if (rates->minimum_linkrate &&
rates->minimum_linkrate < phy->minimum_linkrate_hw)
rates->minimum_linkrate = phy->minimum_linkrate_hw;
if (rates->maximum_linkrate &&
rates->maximum_linkrate > phy->maximum_linkrate_hw)
rates->maximum_linkrate = phy->maximum_linkrate_hw;
if (scsi_is_sas_phy_local(phy)) {
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
rates);
} else {
struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
ret = sas_smp_phy_control(ddev, phy->number,
PHY_FUNC_LINK_RESET, rates);
}
return ret;
}
void sas_prep_resume_ha(struct sas_ha_struct *ha)
{
int i;
set_bit(SAS_HA_REGISTERED, &ha->state);
/* clear out any stale link events/data from the suspension path */
for (i = 0; i < ha->num_phys; i++) {
struct asd_sas_phy *phy = ha->sas_phy[i];
memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
phy->port_events_pending = 0;
phy->phy_events_pending = 0;
phy->frame_rcvd_size = 0;
}
}
EXPORT_SYMBOL(sas_prep_resume_ha);
static int phys_suspended(struct sas_ha_struct *ha)
{
int i, rc = 0;
for (i = 0; i < ha->num_phys; i++) {
struct asd_sas_phy *phy = ha->sas_phy[i];
if (phy->suspended)
rc++;
}
return rc;
}
void sas_resume_ha(struct sas_ha_struct *ha)
{
const unsigned long tmo = msecs_to_jiffies(25000);
int i;
/* deform ports on phys that did not resume
* at this point we may be racing the phy coming back (as posted
* by the lldd). So we post the event and once we are in the
* libsas context check that the phy remains suspended before
* tearing it down.
*/
i = phys_suspended(ha);
if (i)
dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
i, i > 1 ? "s" : "");
wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
for (i = 0; i < ha->num_phys; i++) {
struct asd_sas_phy *phy = ha->sas_phy[i];
if (phy->suspended) {
dev_warn(&phy->phy->dev, "resume timeout\n");
sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT);
}
}
/* all phys are back up or timed out, turn on i/o so we can
* flush out disks that did not return
*/
scsi_unblock_requests(ha->core.shost);
sas_drain_work(ha);
}
EXPORT_SYMBOL(sas_resume_ha);
void sas_suspend_ha(struct sas_ha_struct *ha)
{
int i;
sas_disable_events(ha);
scsi_block_requests(ha->core.shost);
for (i = 0; i < ha->num_phys; i++) {
struct asd_sas_port *port = ha->sas_port[i];
sas_discover_event(port, DISCE_SUSPEND);
}
/* flush suspend events while unregistered */
mutex_lock(&ha->drain_mutex);
__sas_drain_work(ha);
mutex_unlock(&ha->drain_mutex);
}
EXPORT_SYMBOL(sas_suspend_ha);
static void sas_phy_release(struct sas_phy *phy)
{
kfree(phy->hostdata);
phy->hostdata = NULL;
}
static void phy_reset_work(struct work_struct *work)
{
struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
}
static void phy_enable_work(struct work_struct *work)
{
struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
d->enable_result = sas_phy_enable(d->phy, d->enable);
}
static int sas_phy_setup(struct sas_phy *phy)
{
struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
if (!d)
return -ENOMEM;
mutex_init(&d->event_lock);
INIT_SAS_WORK(&d->reset_work, phy_reset_work);
INIT_SAS_WORK(&d->enable_work, phy_enable_work);
d->phy = phy;
phy->hostdata = d;
return 0;
}
static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
{
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
struct sas_phy_data *d = phy->hostdata;
int rc;
if (!d)
return -ENOMEM;
/* libsas workqueue coordinates ata-eh reset with discovery */
mutex_lock(&d->event_lock);
d->reset_result = 0;
d->hard_reset = hard_reset;
spin_lock_irq(&ha->lock);
sas_queue_work(ha, &d->reset_work);
spin_unlock_irq(&ha->lock);
rc = sas_drain_work(ha);
if (rc == 0)
rc = d->reset_result;
mutex_unlock(&d->event_lock);
return rc;
}
static int queue_phy_enable(struct sas_phy *phy, int enable)
{
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
struct sas_phy_data *d = phy->hostdata;
int rc;
if (!d)
return -ENOMEM;
/* libsas workqueue coordinates ata-eh reset with discovery */
mutex_lock(&d->event_lock);
d->enable_result = 0;
d->enable = enable;
spin_lock_irq(&ha->lock);
sas_queue_work(ha, &d->enable_work);
spin_unlock_irq(&ha->lock);
rc = sas_drain_work(ha);
if (rc == 0)
rc = d->enable_result;
mutex_unlock(&d->event_lock);
return rc;
}
static struct sas_function_template sft = {
.phy_enable = queue_phy_enable,
.phy_reset = queue_phy_reset,
.phy_setup = sas_phy_setup,
.phy_release = sas_phy_release,
.set_phy_speed = sas_set_phy_speed,
.get_linkerrors = sas_get_linkerrors,
.smp_handler = sas_smp_handler,
};
struct scsi_transport_template *
sas_domain_attach_transport(struct sas_domain_function_template *dft)
{
struct scsi_transport_template *stt = sas_attach_transport(&sft);
struct sas_internal *i;
if (!stt)
return stt;
i = to_sas_internal(stt);
i->dft = dft;
stt->create_work_queue = 1;
stt->eh_timed_out = sas_scsi_timed_out;
stt->eh_strategy_handler = sas_scsi_recover_host;
return stt;
}
EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
void sas_domain_release_transport(struct scsi_transport_template *stt)
{
sas_release_transport(stt);
}
EXPORT_SYMBOL_GPL(sas_domain_release_transport);
/* ---------- SAS Class register/unregister ---------- */
static int __init sas_class_init(void)
{
sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
if (!sas_task_cache)
return -ENOMEM;
return 0;
}
static void __exit sas_class_exit(void)
{
kmem_cache_destroy(sas_task_cache);
}
MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
MODULE_DESCRIPTION("SAS Transport Layer");
MODULE_LICENSE("GPL v2");
module_init(sas_class_init);
module_exit(sas_class_exit);
EXPORT_SYMBOL_GPL(sas_register_ha);
EXPORT_SYMBOL_GPL(sas_unregister_ha);