[SCSI] libsas: perform sas-transport resets in shost->workq context

Extend the sas transport class to allow transport users to attach extra
data to a sas_phy (->hostdata).  Use this area in libsas to move resets
to workq context in preparation for scheduling ata device resets through
libata-eh.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Dan Williams 2011-12-20 01:03:48 -08:00 committed by James Bottomley
parent b52df4174d
commit 0b3e09da13
5 changed files with 90 additions and 4 deletions

View file

@ -27,7 +27,7 @@
#include "sas_internal.h"
#include "sas_dump.h"
static void sas_queue_work(struct sas_ha_struct *ha, struct work_struct *work)
void sas_queue_work(struct sas_ha_struct *ha, struct work_struct *work)
{
if (!test_bit(SAS_HA_REGISTERED, &ha->state))
return;

View file

@ -290,9 +290,66 @@ int sas_set_phy_speed(struct sas_phy *phy,
return ret;
}
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);
d->reset_result = sas_phy_reset(d->phy, d->hard_reset);
}
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_WORK(&d->reset_work, phy_reset_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->state_lock);
sas_queue_work(ha, &d->reset_work);
spin_unlock_irq(&ha->state_lock);
rc = sas_drain_work(ha);
if (rc == 0)
rc = d->reset_result;
mutex_unlock(&d->event_lock);
return rc;
}
static struct sas_function_template sft = {
.phy_enable = sas_phy_enable,
.phy_reset = sas_phy_reset,
.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,

View file

@ -38,6 +38,15 @@
#define TO_SAS_TASK(_scsi_cmd) ((void *)(_scsi_cmd)->host_scribble)
#define ASSIGN_SAS_TASK(_sc, _t) do { (_sc)->host_scribble = (void *) _t; } while (0)
struct sas_phy_data {
/* let reset be performed in sas_queue_work() context */
struct sas_phy *phy;
struct mutex event_lock;
int hard_reset;
int reset_result;
struct work_struct reset_work;
};
void sas_scsi_recover_host(struct Scsi_Host *shost);
int sas_show_class(enum sas_class class, char *buf);
@ -66,6 +75,7 @@ void sas_porte_broadcast_rcvd(struct work_struct *work);
void sas_porte_link_reset_err(struct work_struct *work);
void sas_porte_timer_event(struct work_struct *work);
void sas_porte_hard_reset(struct work_struct *work);
void sas_queue_work(struct sas_ha_struct *ha, struct work_struct *work);
int sas_notify_lldd_dev_found(struct domain_device *);
void sas_notify_lldd_dev_gone(struct domain_device *);

View file

@ -652,9 +652,21 @@ sas_phy_linkerror_attr(running_disparity_error_count);
sas_phy_linkerror_attr(loss_of_dword_sync_count);
sas_phy_linkerror_attr(phy_reset_problem_count);
static int sas_phy_setup(struct transport_container *tc, struct device *dev,
struct device *cdev)
{
struct sas_phy *phy = dev_to_phy(dev);
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_internal *i = to_sas_internal(shost->transportt);
if (i->f->phy_setup)
i->f->phy_setup(phy);
return 0;
}
static DECLARE_TRANSPORT_CLASS(sas_phy_class,
"sas_phy", NULL, NULL, NULL);
"sas_phy", sas_phy_setup, NULL, NULL);
static int sas_phy_match(struct attribute_container *cont, struct device *dev)
{
@ -678,7 +690,11 @@ static int sas_phy_match(struct attribute_container *cont, struct device *dev)
static void sas_phy_release(struct device *dev)
{
struct sas_phy *phy = dev_to_phy(dev);
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_internal *i = to_sas_internal(shost->transportt);
if (i->f->phy_release)
i->f->phy_release(phy);
put_device(dev->parent);
kfree(phy);
}

View file

@ -75,7 +75,8 @@ struct sas_phy {
/* for the list of phys belonging to a port */
struct list_head port_siblings;
struct work_struct reset_work;
/* available to the lldd */
void *hostdata;
};
#define dev_to_phy(d) \
@ -169,6 +170,8 @@ struct sas_function_template {
int (*get_bay_identifier)(struct sas_rphy *);
int (*phy_reset)(struct sas_phy *, int);
int (*phy_enable)(struct sas_phy *, int);
int (*phy_setup)(struct sas_phy *);
void (*phy_release)(struct sas_phy *);
int (*set_phy_speed)(struct sas_phy *, struct sas_phy_linkrates *);
int (*smp_handler)(struct Scsi_Host *, struct sas_rphy *, struct request *);
};