Introduce wait-complete for libsas sas event processing,
execute sas port create/destruct in sync.
Signed-off-by: Yijing Wang <wangyij...@huawei.com>
CC: John Garry <john.ga...@huawei.com>
CC: Johannes Thumshirn <jthumsh...@suse.de>
CC: Ewan Milne <emi...@redhat.com>
CC: Christoph Hellwig <h...@lst.de>
CC: Tomas Henzl <the...@redhat.com>
CC: Dan Williams <dan.j.willi...@intel.com>
---
drivers/scsi/libsas/sas_discover.c | 41 ++++++++++++++++++++++++++++----------
drivers/scsi/libsas/sas_internal.h | 34 +++++++++++++++++++++++++++++++
drivers/scsi/libsas/sas_port.c | 4 ++++
include/scsi/libsas.h | 5 ++++-
4 files changed, 72 insertions(+), 12 deletions(-)
diff --git a/drivers/scsi/libsas/sas_discover.c
b/drivers/scsi/libsas/sas_discover.c
index 60de662..5d4a3a8 100644
--- a/drivers/scsi/libsas/sas_discover.c
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -525,16 +525,43 @@ static void sas_revalidate_domain(struct work_struct
*work)
mutex_unlock(&ha->disco_mutex);
}
+static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
+ [DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
+ [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
+ [DISCE_PROBE] = sas_probe_devices,
+ [DISCE_SUSPEND] = sas_suspend_devices,
+ [DISCE_RESUME] = sas_resume_devices,
+ [DISCE_DESTRUCT] = sas_destruct_devices,
+};
+
+/* a simple wrapper for sas discover event funtions */
+static void sas_discover_common_fn(struct work_struct *work)
+{
+ struct sas_discovery_event *ev = to_sas_discovery_event(work);
+ struct asd_sas_port *port = ev->port;
+
+ sas_event_fns[ev->type](work);
+ sas_port_put(port);
+}
+
+
/* ---------- Events ---------- */
static void sas_chain_work(struct sas_ha_struct *ha, struct sas_work *sw)
{
+ int ret;
+ struct sas_discovery_event *ev = to_sas_discovery_event(&sw->work);
+ struct asd_sas_port *port = ev->port;
+
/* chained work is not subject to SA_HA_DRAINING or
* SAS_HA_REGISTERED, because it is either submitted in the
* workqueue, or known to be submitted from a context that is
* not racing against draining
*/
- scsi_queue_work(ha->core.shost, &sw->work);
+ sas_port_get(port);
+ ret = scsi_queue_work(ha->core.shost, &sw->work);
+ if (ret != 1)
+ sas_port_put(port);
}
static void sas_chain_event(int event, unsigned long *pending,
@@ -575,18 +602,10 @@ void sas_init_disc(struct sas_discovery *disc, struct
asd_sas_port *port)
{
int i;
- static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
- [DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
- [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
- [DISCE_PROBE] = sas_probe_devices,
- [DISCE_SUSPEND] = sas_suspend_devices,
- [DISCE_RESUME] = sas_resume_devices,
- [DISCE_DESTRUCT] = sas_destruct_devices,
- };
-
disc->pending = 0;
for (i = 0; i < DISC_NUM_EVENTS; i++) {
- INIT_SAS_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
+ INIT_SAS_WORK(&disc->disc_work[i].work, sas_discover_common_fn);
disc->disc_work[i].port = port;
+ disc->disc_work[i].type = i;
}
}
diff --git a/drivers/scsi/libsas/sas_internal.h
b/drivers/scsi/libsas/sas_internal.h
index f03ce64..890b5d26 100644
--- a/drivers/scsi/libsas/sas_internal.h
+++ b/drivers/scsi/libsas/sas_internal.h
@@ -100,6 +100,40 @@ void sas_free_device(struct kref *kref);
extern const work_func_t sas_phy_event_fns[PHY_NUM_EVENTS];
extern const work_func_t sas_port_event_fns[PORT_NUM_EVENTS];
+static void sas_complete_event(struct kref *kref)
+{
+ struct asd_sas_port *port = container_of(kref, struct asd_sas_port,
ref);
+
+ complete_all(&port->completion);
+}
+
+static inline void sas_port_put(struct asd_sas_port *port)
+{
+ if (port->is_sync)
+ kref_put(&port->ref, sas_complete_event);
+}
+
+static inline void sas_port_wait_init(struct asd_sas_port *port)
+{
+ init_completion(&port->completion);
+ kref_init(&port->ref);
+ port->is_sync = true;
+}
+
+static inline void sas_port_wait_completion(
+ struct asd_sas_port *port)
+{
+ sas_port_put(port);
+ wait_for_completion(&port->completion);
+ port->is_sync = false;
+}
+
+static inline void sas_port_get(struct asd_sas_port *port)
+{
+ if (port && port->is_sync)
+ kref_get(&port->ref);
+}
+
#ifdef CONFIG_SCSI_SAS_HOST_SMP
extern int sas_smp_host_handler(struct Scsi_Host *shost, struct request *req,
struct request *rsp);
diff --git a/drivers/scsi/libsas/sas_port.c b/drivers/scsi/libsas/sas_port.c
index 9326628..d589adb 100644
--- a/drivers/scsi/libsas/sas_port.c
+++ b/drivers/scsi/libsas/sas_port.c
@@ -191,7 +191,9 @@ static void sas_form_port(struct asd_sas_phy *phy)
if (si->dft->lldd_port_formed)
si->dft->lldd_port_formed(phy);
+ sas_port_wait_init(port);
sas_discover_event(phy->port, DISCE_DISCOVER_DOMAIN);
+ sas_port_wait_completion(port);
}
/**
@@ -218,7 +220,9 @@ void sas_deform_port(struct asd_sas_phy *phy, int gone)
dev->pathways--;
if (port->num_phys == 1) {
+ sas_port_wait_init(port);
sas_unregister_domain_devices(port, gone);
+ sas_port_wait_completion(port);
sas_port_delete(port->port);
port->port = NULL;
} else {
diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index a01ca42..c2ef05e 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -242,6 +242,7 @@ static inline void INIT_SAS_WORK(struct sas_work *sw, void
(*fn)(struct work_str
struct sas_discovery_event {
struct sas_work work;
struct asd_sas_port *port;
+ enum discover_event type;
};
static inline struct sas_discovery_event *to_sas_discovery_event(struct
work_struct *work)
@@ -273,7 +274,9 @@ struct asd_sas_port {
struct sas_work work;
int suspended;
-
+ struct kref ref;
+ struct completion completion;
+ bool is_sync;
/* public: */
int id;
--
2.5.0
