[SCSI] zfcp: Replace global config_lock with local list locks
The global config_lock was used to protect the configuration organized
in independent lists. It is not necessary to have a lock on driver
level for this purpose. This patch replaces the global config_lock
with a set of local list locks.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index f73e218..464f047 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -99,9 +99,12 @@
if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
zfcp_erp_action_dismiss(&port->erp_action);
- else
- list_for_each_entry(unit, &port->unit_list_head, list)
- zfcp_erp_action_dismiss_unit(unit);
+ else {
+ read_lock(&port->unit_list_lock);
+ list_for_each_entry(unit, &port->unit_list, list)
+ zfcp_erp_action_dismiss_unit(unit);
+ read_unlock(&port->unit_list_lock);
+ }
}
static void zfcp_erp_action_dismiss_adapter(struct zfcp_adapter *adapter)
@@ -110,9 +113,12 @@
if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
zfcp_erp_action_dismiss(&adapter->erp_action);
- else
- list_for_each_entry(port, &adapter->port_list_head, list)
+ else {
+ read_lock(&adapter->port_list_lock);
+ list_for_each_entry(port, &adapter->port_list, list)
zfcp_erp_action_dismiss_port(port);
+ read_unlock(&adapter->port_list_lock);
+ }
}
static int zfcp_erp_required_act(int want, struct zfcp_adapter *adapter,
@@ -264,11 +270,16 @@
{
unsigned long flags;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- write_lock(&adapter->erp_lock);
- _zfcp_erp_adapter_reopen(adapter, clear, id, ref);
- write_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ zfcp_erp_adapter_block(adapter, clear);
+ zfcp_scsi_schedule_rports_block(adapter);
+
+ write_lock_irqsave(&adapter->erp_lock, flags);
+ if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
+ zfcp_erp_adapter_failed(adapter, "erareo1", NULL);
+ else
+ zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER, adapter,
+ NULL, NULL, id, ref);
+ write_unlock_irqrestore(&adapter->erp_lock, flags);
}
/**
@@ -345,11 +356,9 @@
unsigned long flags;
struct zfcp_adapter *adapter = port->adapter;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- write_lock(&adapter->erp_lock);
+ write_lock_irqsave(&adapter->erp_lock, flags);
_zfcp_erp_port_forced_reopen(port, clear, id, ref);
- write_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ write_unlock_irqrestore(&adapter->erp_lock, flags);
}
static int _zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id,
@@ -377,15 +386,13 @@
*/
int zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id, void *ref)
{
- unsigned long flags;
int retval;
+ unsigned long flags;
struct zfcp_adapter *adapter = port->adapter;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- write_lock(&adapter->erp_lock);
+ write_lock_irqsave(&adapter->erp_lock, flags);
retval = _zfcp_erp_port_reopen(port, clear, id, ref);
- write_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ write_unlock_irqrestore(&adapter->erp_lock, flags);
return retval;
}
@@ -424,11 +431,9 @@
struct zfcp_port *port = unit->port;
struct zfcp_adapter *adapter = port->adapter;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- write_lock(&adapter->erp_lock);
+ write_lock_irqsave(&adapter->erp_lock, flags);
_zfcp_erp_unit_reopen(unit, clear, id, ref);
- write_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ write_unlock_irqrestore(&adapter->erp_lock, flags);
}
static int status_change_set(unsigned long mask, atomic_t *status)
@@ -540,8 +545,10 @@
{
struct zfcp_port *port;
- list_for_each_entry(port, &adapter->port_list_head, list)
+ read_lock(&adapter->port_list_lock);
+ list_for_each_entry(port, &adapter->port_list, list)
_zfcp_erp_port_reopen(port, clear, id, ref);
+ read_unlock(&adapter->port_list_lock);
}
static void _zfcp_erp_unit_reopen_all(struct zfcp_port *port, int clear,
@@ -549,8 +556,10 @@
{
struct zfcp_unit *unit;
- list_for_each_entry(unit, &port->unit_list_head, list)
+ read_lock(&port->unit_list_lock);
+ list_for_each_entry(unit, &port->unit_list, list)
_zfcp_erp_unit_reopen(unit, clear, id, ref);
+ read_unlock(&port->unit_list_lock);
}
static void zfcp_erp_strategy_followup_failed(struct zfcp_erp_action *act)
@@ -590,16 +599,14 @@
{
unsigned long flags;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- read_lock(&adapter->erp_lock);
+ read_lock_irqsave(&adapter->erp_lock, flags);
if (list_empty(&adapter->erp_ready_head) &&
list_empty(&adapter->erp_running_head)) {
atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_PENDING,
&adapter->status);
wake_up(&adapter->erp_done_wqh);
}
- read_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ read_unlock_irqrestore(&adapter->erp_lock, flags);
}
static int zfcp_erp_adapter_strategy_open_qdio(struct zfcp_erp_action *act)
@@ -1214,11 +1221,10 @@
static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
{
int retval;
- struct zfcp_adapter *adapter = erp_action->adapter;
unsigned long flags;
+ struct zfcp_adapter *adapter = erp_action->adapter;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- write_lock(&adapter->erp_lock);
+ write_lock_irqsave(&adapter->erp_lock, flags);
zfcp_erp_strategy_check_fsfreq(erp_action);
@@ -1231,11 +1237,9 @@
zfcp_erp_action_to_running(erp_action);
/* no lock to allow for blocking operations */
- write_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ write_unlock_irqrestore(&adapter->erp_lock, flags);
retval = zfcp_erp_strategy_do_action(erp_action);
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- write_lock(&adapter->erp_lock);
+ write_lock_irqsave(&adapter->erp_lock, flags);
if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED)
retval = ZFCP_ERP_CONTINUES;
@@ -1273,8 +1277,7 @@
zfcp_erp_strategy_followup_failed(erp_action);
unlock:
- write_unlock(&adapter->erp_lock);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ write_unlock_irqrestore(&adapter->erp_lock, flags);
if (retval != ZFCP_ERP_CONTINUES)
zfcp_erp_action_cleanup(erp_action, retval);
@@ -1415,6 +1418,7 @@
void *ref, u32 mask, int set_or_clear)
{
struct zfcp_port *port;
+ unsigned long flags;
u32 common_mask = mask & ZFCP_COMMON_FLAGS;
if (set_or_clear == ZFCP_SET) {
@@ -1429,10 +1433,13 @@
atomic_set(&adapter->erp_counter, 0);
}
- if (common_mask)
- list_for_each_entry(port, &adapter->port_list_head, list)
+ if (common_mask) {
+ read_lock_irqsave(&adapter->port_list_lock, flags);
+ list_for_each_entry(port, &adapter->port_list, list)
zfcp_erp_modify_port_status(port, id, ref, common_mask,
set_or_clear);
+ read_unlock_irqrestore(&adapter->port_list_lock, flags);
+ }
}
/**
@@ -1449,6 +1456,7 @@
u32 mask, int set_or_clear)
{
struct zfcp_unit *unit;
+ unsigned long flags;
u32 common_mask = mask & ZFCP_COMMON_FLAGS;
if (set_or_clear == ZFCP_SET) {
@@ -1463,10 +1471,13 @@
atomic_set(&port->erp_counter, 0);
}
- if (common_mask)
- list_for_each_entry(unit, &port->unit_list_head, list)
+ if (common_mask) {
+ read_lock_irqsave(&port->unit_list_lock, flags);
+ list_for_each_entry(unit, &port->unit_list, list)
zfcp_erp_modify_unit_status(unit, id, ref, common_mask,
set_or_clear);
+ read_unlock_irqrestore(&port->unit_list_lock, flags);
+ }
}
/**
@@ -1502,12 +1513,8 @@
*/
void zfcp_erp_port_boxed(struct zfcp_port *port, char *id, void *ref)
{
- unsigned long flags;
-
- read_lock_irqsave(&zfcp_data.config_lock, flags);
zfcp_erp_modify_port_status(port, id, ref,
ZFCP_STATUS_COMMON_ACCESS_BOXED, ZFCP_SET);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED, id, ref);
}
@@ -1535,13 +1542,9 @@
*/
void zfcp_erp_port_access_denied(struct zfcp_port *port, char *id, void *ref)
{
- unsigned long flags;
-
- read_lock_irqsave(&zfcp_data.config_lock, flags);
zfcp_erp_modify_port_status(port, id, ref,
ZFCP_STATUS_COMMON_ERP_FAILED |
ZFCP_STATUS_COMMON_ACCESS_DENIED, ZFCP_SET);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}
/**
@@ -1574,12 +1577,15 @@
void *ref)
{
struct zfcp_unit *unit;
+ unsigned long flags;
int status = atomic_read(&port->status);
if (!(status & (ZFCP_STATUS_COMMON_ACCESS_DENIED |
ZFCP_STATUS_COMMON_ACCESS_BOXED))) {
- list_for_each_entry(unit, &port->unit_list_head, list)
+ read_lock_irqsave(&port->unit_list_lock, flags);
+ list_for_each_entry(unit, &port->unit_list, list)
zfcp_erp_unit_access_changed(unit, id, ref);
+ read_unlock_irqrestore(&port->unit_list_lock, flags);
return;
}
@@ -1595,14 +1601,14 @@
void zfcp_erp_adapter_access_changed(struct zfcp_adapter *adapter, char *id,
void *ref)
{
- struct zfcp_port *port;
unsigned long flags;
+ struct zfcp_port *port;
if (adapter->connection_features & FSF_FEATURE_NPIV_MODE)
return;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- list_for_each_entry(port, &adapter->port_list_head, list)
+ read_lock_irqsave(&adapter->port_list_lock, flags);
+ list_for_each_entry(port, &adapter->port_list, list)
zfcp_erp_port_access_changed(port, id, ref);
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
+ read_unlock_irqrestore(&adapter->port_list_lock, flags);
}