bonding: Convert more locks to _bh, acquire rtnl, for new locking

	Convert more lock acquisitions to _bh flavor to avoid deadlock
with workqueue activity and add acquisition of RTNL in appropriate places.
Affects ALB mode, as well as core bonding functions and sysfs.

Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

3 files changed, 29 insertions, 23 deletions

diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
index f2e2872c9b17..6db5d763f6b6 100644
--- a/drivers/net/bonding/bond_alb.c
+++ b/drivers/net/bonding/bond_alb.c
@@ -128,12 +128,12 @@ static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
 
 static inline void _lock_tx_hashtbl(struct bonding *bond)
 {
-        spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
+        spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 }
 
 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 {
-        spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
+        spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 }
 
 /* Caller must hold tx_hashtbl lock */
@@ -305,12 +305,12 @@ static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u3
 /*********************** rlb specific functions ***************************/
 static inline void _lock_rx_hashtbl(struct bonding *bond)
 {
-        spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
+        spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 }
 
 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 {
-        spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
+        spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 }
 
 /* when an ARP REPLY is received from a client update its info
@@ -472,13 +472,13 @@ static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 
         _unlock_rx_hashtbl(bond);
 
-        write_lock(&bond->curr_slave_lock);
+        write_lock_bh(&bond->curr_slave_lock);
 
         if (slave != bond->curr_active_slave) {
                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
         }
 
-        write_unlock(&bond->curr_slave_lock);
+        write_unlock_bh(&bond->curr_slave_lock);
 }
 
 static void rlb_update_client(struct rlb_client_info *client_info)
@@ -1519,11 +1519,11 @@ int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
         /* caller must hold the bond lock for write since the mac addresses
          * are compared and may be swapped.
          */
-        write_lock_bh(&bond->lock);
+        read_lock(&bond->lock);
 
         res = alb_handle_addr_collision_on_attach(bond, slave);
 
-        write_unlock_bh(&bond->lock);
+        read_unlock(&bond->lock);
 
         if (res) {
                 return res;
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 15c1f7ad222b..6909becb10f6 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1846,9 +1846,9 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
 */
 void bond_destroy(struct bonding *bond)
 {
+        unregister_netdevice(bond->dev);
         bond_deinit(bond->dev);
         bond_destroy_sysfs_entry(bond);
-        unregister_netdevice(bond->dev);
 }
 
 /*
@@ -2057,9 +2057,9 @@ static int bond_info_query(struct net_device *bond_dev, struct ifbond *info)
         info->bond_mode = bond->params.mode;
         info->miimon = bond->params.miimon;
 
-        read_lock_bh(&bond->lock);
+        read_lock(&bond->lock);
         info->num_slaves = bond->slave_cnt;
-        read_unlock_bh(&bond->lock);
+        read_unlock(&bond->lock);
 
         return 0;
 }
@@ -2074,7 +2074,7 @@ static int bond_slave_info_query(struct net_device *bond_dev, struct ifslave *in
                 return -ENODEV;
         }
 
-        read_lock_bh(&bond->lock);
+        read_lock(&bond->lock);
 
         bond_for_each_slave(bond, slave, i) {
                 if (i == (int)info->slave_id) {
@@ -2083,7 +2083,7 @@ static int bond_slave_info_query(struct net_device *bond_dev, struct ifslave *in
                 }
         }
 
-        read_unlock_bh(&bond->lock);
+        read_unlock(&bond->lock);
 
         if (found) {
                 strcpy(info->slave_name, slave->dev->name);
@@ -3078,7 +3078,7 @@ static void *bond_info_seq_start(struct seq_file *seq, loff_t *pos)
 
         /* make sure the bond won't be taken away */
         read_lock(&dev_base_lock);
-        read_lock_bh(&bond->lock);
+        read_lock(&bond->lock);
 
         if (*pos == 0) {
                 return SEQ_START_TOKEN;
@@ -3112,7 +3112,7 @@ static void bond_info_seq_stop(struct seq_file *seq, void *v)
 {
         struct bonding *bond = seq->private;
 
-        read_unlock_bh(&bond->lock);
+        read_unlock(&bond->lock);
         read_unlock(&dev_base_lock);
 }
 
@@ -3821,13 +3821,13 @@ static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd
                 if (mii->reg_num == 1) {
                         struct bonding *bond = bond_dev->priv;
                         mii->val_out = 0;
-                        read_lock_bh(&bond->lock);
+                        read_lock(&bond->lock);
                         read_lock(&bond->curr_slave_lock);
                         if (netif_carrier_ok(bond->dev)) {
                                 mii->val_out = BMSR_LSTATUS;
                         }
                         read_unlock(&bond->curr_slave_lock);
-                        read_unlock_bh(&bond->lock);
+                        read_unlock(&bond->lock);
                 }
 
                 return 0;
@@ -4473,8 +4473,8 @@ static void bond_free_all(void)
                 bond_mc_list_destroy(bond);
                 /* Release the bonded slaves */
                 bond_release_all(bond_dev);
-                bond_deinit(bond_dev);
                 unregister_netdevice(bond_dev);
+                bond_deinit(bond_dev);
         }
 
 #ifdef CONFIG_PROC_FS
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index 19d970e0cbb8..7a06ade85b02 100644
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -229,7 +229,7 @@ static ssize_t bonding_show_slaves(struct device *d,
         int i, res = 0;
         struct bonding *bond = to_bond(d);
 
-        read_lock_bh(&bond->lock);
+        read_lock(&bond->lock);
         bond_for_each_slave(bond, slave, i) {
                 if (res > (PAGE_SIZE - IFNAMSIZ)) {
                         /* not enough space for another interface name */
@@ -240,7 +240,7 @@ static ssize_t bonding_show_slaves(struct device *d,
                 }
                 res += sprintf(buf + res, "%s ", slave->dev->name);
         }
-        read_unlock_bh(&bond->lock);
+        read_unlock(&bond->lock);
         res += sprintf(buf + res, "\n");
         res++;
         return res;
@@ -282,18 +282,18 @@ static ssize_t bonding_store_slaves(struct device *d,
 
                 /* Got a slave name in ifname.  Is it already in the list? */
                 found = 0;
-                read_lock_bh(&bond->lock);
+                read_lock(&bond->lock);
                 bond_for_each_slave(bond, slave, i)
                         if (strnicmp(slave->dev->name, ifname, IFNAMSIZ) == 0) {
                                 printk(KERN_ERR DRV_NAME
                                        ": %s: Interface %s is already enslaved!\n",
                                        bond->dev->name, ifname);
                                 ret = -EPERM;
-                                read_unlock_bh(&bond->lock);
+                                read_unlock(&bond->lock);
                                 goto out;
                         }
 
-                read_unlock_bh(&bond->lock);
+                read_unlock(&bond->lock);
                 printk(KERN_INFO DRV_NAME ": %s: Adding slave %s.\n",
                        bond->dev->name, ifname);
                 dev = dev_get_by_name(&init_net, ifname);
@@ -1133,6 +1133,9 @@ static ssize_t bonding_store_primary(struct device *d,
         }
 out:
         write_unlock_bh(&bond->lock);
+
+        rtnl_unlock();
+
         return count;
 }
 static DEVICE_ATTR(primary, S_IRUGO | S_IWUSR, bonding_show_primary, bonding_store_primary);
@@ -1190,6 +1193,7 @@ static ssize_t bonding_show_active_slave(struct device *d,
         struct bonding *bond = to_bond(d);
         int count;
 
+        rtnl_lock();
 
         read_lock(&bond->curr_slave_lock);
         curr = bond->curr_active_slave;
@@ -1269,6 +1273,8 @@ static ssize_t bonding_store_active_slave(struct device *d,
         }
 out:
         write_unlock_bh(&bond->lock);
+        rtnl_unlock();
+
         return count;
 
 }