ehea: fix circular locking problem

This patch fixes the circular locking problem by changing the locking strategy
concerning the logging of firmware handles.

Signed-off-by: Jan-Bernd Themann <themann@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 30 insertions, 26 deletions

diff --git a/drivers/net/ehea/ehea_main.c b/drivers/net/ehea/ehea_main.c
index 40c34bfe2cfa..ac0c5b438e0a 100644
--- a/drivers/net/ehea/ehea_main.c
+++ b/drivers/net/ehea/ehea_main.c
@@ -155,6 +155,8 @@ static void ehea_update_firmware_handles(void)
         int num_fw_handles, k, l;
 
         /* Determine number of handles */
+        mutex_lock(&ehea_fw_handles.lock);
+
         list_for_each_entry(adapter, &adapter_list, list) {
                 num_adapters++;
 
@@ -176,15 +178,19 @@ static void ehea_update_firmware_handles(void)
         if (num_fw_handles) {
                 arr = kzalloc(num_fw_handles * sizeof(*arr), GFP_KERNEL);
                 if (!arr)
-                        return;  /* Keep the existing array */
+                        goto out;  /* Keep the existing array */
         } else
                 goto out_update;
 
         list_for_each_entry(adapter, &adapter_list, list) {
+                if (num_adapters == 0)
+                        break;
+
                 for (k = 0; k < EHEA_MAX_PORTS; k++) {
                         struct ehea_port *port = adapter->port[k];
 
-                        if (!port || (port->state != EHEA_PORT_UP))
+                        if (!port || (port->state != EHEA_PORT_UP)
+                                || (num_ports == 0))
                                 continue;
 
                         for (l = 0;
@@ -207,6 +213,7 @@ static void ehea_update_firmware_handles(void)
                         }
                         arr[i].adh = adapter->handle;
                         arr[i++].fwh = port->qp_eq->fw_handle;
+                        num_ports--;
                 }
 
                 arr[i].adh = adapter->handle;
@@ -216,16 +223,20 @@ static void ehea_update_firmware_handles(void)
                         arr[i].adh = adapter->handle;
                         arr[i++].fwh = adapter->mr.handle;
                 }
+                num_adapters--;
         }
 
 out_update:
         kfree(ehea_fw_handles.arr);
         ehea_fw_handles.arr = arr;
         ehea_fw_handles.num_entries = i;
+out:
+        mutex_unlock(&ehea_fw_handles.lock);
 }
 
 static void ehea_update_bcmc_registrations(void)
 {
+        unsigned long flags;
         struct ehea_bcmc_reg_entry *arr = NULL;
         struct ehea_adapter *adapter;
         struct ehea_mc_list *mc_entry;
@@ -233,6 +244,8 @@ static void ehea_update_bcmc_registrations(void)
         int i = 0;
         int k;
 
+        spin_lock_irqsave(&ehea_bcmc_regs.lock, flags);
+
         /* Determine number of registrations */
         list_for_each_entry(adapter, &adapter_list, list)
                 for (k = 0; k < EHEA_MAX_PORTS; k++) {
@@ -250,7 +263,7 @@ static void ehea_update_bcmc_registrations(void)
         if (num_registrations) {
                 arr = kzalloc(num_registrations * sizeof(*arr), GFP_ATOMIC);
                 if (!arr)
-                        return;  /* Keep the existing array */
+                        goto out;  /* Keep the existing array */
         } else
                 goto out_update;
 
@@ -261,6 +274,9 @@ static void ehea_update_bcmc_registrations(void)
                         if (!port || (port->state != EHEA_PORT_UP))
                                 continue;
 
+                        if (num_registrations == 0)
+                                goto out_update;
+
                         arr[i].adh = adapter->handle;
                         arr[i].port_id = port->logical_port_id;
                         arr[i].reg_type = EHEA_BCMC_BROADCAST |
@@ -272,9 +288,13 @@ static void ehea_update_bcmc_registrations(void)
                         arr[i].reg_type = EHEA_BCMC_BROADCAST |
                                           EHEA_BCMC_VLANID_ALL;
                         arr[i++].macaddr = port->mac_addr;
+                        num_registrations -= 2;
 
                         list_for_each_entry(mc_entry,
                                             &port->mc_list->list, list) {
+                                if (num_registrations == 0)
+                                        goto out_update;
+
                                 arr[i].adh = adapter->handle;
                                 arr[i].port_id = port->logical_port_id;
                                 arr[i].reg_type = EHEA_BCMC_SCOPE_ALL |
@@ -288,6 +308,7 @@ static void ehea_update_bcmc_registrations(void)
                                                   EHEA_BCMC_MULTICAST |
                                                   EHEA_BCMC_VLANID_ALL;
                                 arr[i++].macaddr = mc_entry->macaddr;
+                                num_registrations -= 2;
                         }
                 }
         }
@@ -296,6 +317,8 @@ out_update:
         kfree(ehea_bcmc_regs.arr);
         ehea_bcmc_regs.arr = arr;
         ehea_bcmc_regs.num_entries = i;
+out:
+        spin_unlock_irqrestore(&ehea_bcmc_regs.lock, flags);
 }
 
 static struct net_device_stats *ehea_get_stats(struct net_device *dev)
@@ -1762,8 +1785,6 @@ static int ehea_set_mac_addr(struct net_device *dev, void *sa)
 
         memcpy(dev->dev_addr, mac_addr->sa_data, dev->addr_len);
 
-        spin_lock(&ehea_bcmc_regs.lock);
-
         /* Deregister old MAC in pHYP */
         if (port->state == EHEA_PORT_UP) {
                 ret = ehea_broadcast_reg_helper(port, H_DEREG_BCMC);
@@ -1784,7 +1805,6 @@ static int ehea_set_mac_addr(struct net_device *dev, void *sa)
 
 out_upregs:
         ehea_update_bcmc_registrations();
-        spin_unlock(&ehea_bcmc_regs.lock);
 out_free:
         free_page((unsigned long)cb0);
 out:
@@ -1946,8 +1966,6 @@ static void ehea_set_multicast_list(struct net_device *dev)
         }
         ehea_promiscuous(dev, 0);
 
-        spin_lock(&ehea_bcmc_regs.lock);
-
         if (dev->flags & IFF_ALLMULTI) {
                 ehea_allmulti(dev, 1);
                 goto out;
@@ -1977,7 +1995,6 @@ static void ehea_set_multicast_list(struct net_device *dev)
         }
 out:
         ehea_update_bcmc_registrations();
-        spin_unlock(&ehea_bcmc_regs.lock);
         return;
 }
 
@@ -2458,8 +2475,6 @@ static int ehea_up(struct net_device *dev)
         if (port->state == EHEA_PORT_UP)
                 return 0;
 
-        mutex_lock(&ehea_fw_handles.lock);
-
         ret = ehea_port_res_setup(port, port->num_def_qps,
                                   port->num_add_tx_qps);
         if (ret) {
@@ -2496,8 +2511,6 @@ static int ehea_up(struct net_device *dev)
                 }
         }
 
-        spin_lock(&ehea_bcmc_regs.lock);
-
         ret = ehea_broadcast_reg_helper(port, H_REG_BCMC);
         if (ret) {
                 ret = -EIO;
@@ -2519,10 +2532,7 @@ out:
                 ehea_info("Failed starting %s. ret=%i", dev->name, ret);
 
         ehea_update_bcmc_registrations();
-        spin_unlock(&ehea_bcmc_regs.lock);
-
         ehea_update_firmware_handles();
-        mutex_unlock(&ehea_fw_handles.lock);
 
         return ret;
 }
@@ -2572,9 +2582,6 @@ static int ehea_down(struct net_device *dev)
         if (port->state == EHEA_PORT_DOWN)
                 return 0;
 
-        mutex_lock(&ehea_fw_handles.lock);
-
-        spin_lock(&ehea_bcmc_regs.lock);
         ehea_drop_multicast_list(dev);
         ehea_broadcast_reg_helper(port, H_DEREG_BCMC);
 
@@ -2583,7 +2590,6 @@ static int ehea_down(struct net_device *dev)
         port->state = EHEA_PORT_DOWN;
 
         ehea_update_bcmc_registrations();
-        spin_unlock(&ehea_bcmc_regs.lock);
 
         ret = ehea_clean_all_portres(port);
         if (ret)
@@ -2591,7 +2597,6 @@ static int ehea_down(struct net_device *dev)
                           dev->name, ret);
 
         ehea_update_firmware_handles();
-        mutex_unlock(&ehea_fw_handles.lock);
 
         return ret;
 }
@@ -3368,7 +3373,6 @@ static int __devinit ehea_probe_adapter(struct of_device *dev,
                 ehea_error("Invalid ibmebus device probed");
                 return -EINVAL;
         }
-        mutex_lock(&ehea_fw_handles.lock);
 
         adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
         if (!adapter) {
@@ -3453,7 +3457,7 @@ out_free_ad:
 
 out:
         ehea_update_firmware_handles();
-        mutex_unlock(&ehea_fw_handles.lock);
+
         return ret;
 }
 
@@ -3472,8 +3476,6 @@ static int __devexit ehea_remove(struct of_device *dev)
 
         flush_scheduled_work();
 
-        mutex_lock(&ehea_fw_handles.lock);
-
         ibmebus_free_irq(adapter->neq->attr.ist1, adapter);
         tasklet_kill(&adapter->neq_tasklet);
 
@@ -3483,7 +3485,6 @@ static int __devexit ehea_remove(struct of_device *dev)
         kfree(adapter);
 
         ehea_update_firmware_handles();
-        mutex_unlock(&ehea_fw_handles.lock);
 
         return 0;
 }
@@ -3532,6 +3533,9 @@ static int ehea_mem_notifier(struct notifier_block *nb,
         default:
                 break;
         }
+
+        ehea_update_firmware_handles();
+
         return NOTIFY_OK;
 }