rcu: fix hotplug vs rcu race
[safe/jmp/linux-2.6] / drivers / net / bonding / bond_sysfs.c
index 19d970e..08f3d39 100644 (file)
@@ -74,7 +74,7 @@ struct rw_semaphore bonding_rwsem;
  * "show" function for the bond_masters attribute.
  * The class parameter is ignored.
  */
-static ssize_t bonding_show_bonds(struct class *cls, char *buffer)
+static ssize_t bonding_show_bonds(struct class *cls, char *buf)
 {
        int res = 0;
        struct bonding *bond;
@@ -86,14 +86,13 @@ static ssize_t bonding_show_bonds(struct class *cls, char *buffer)
                        /* not enough space for another interface name */
                        if ((PAGE_SIZE - res) > 10)
                                res = PAGE_SIZE - 10;
-                       res += sprintf(buffer + res, "++more++");
+                       res += sprintf(buf + res, "++more++ ");
                        break;
                }
-               res += sprintf(buffer + res, "%s ",
-                              bond->dev->name);
+               res += sprintf(buf + res, "%s ", bond->dev->name);
        }
-       res += sprintf(buffer + res, "\n");
-       res++;
+       if (res)
+               buf[res-1] = '\n'; /* eat the leftover space */
        up_read(&(bonding_rwsem));
        return res;
 }
@@ -110,11 +109,10 @@ static ssize_t bonding_store_bonds(struct class *cls, const char *buffer, size_t
 {
        char command[IFNAMSIZ + 1] = {0, };
        char *ifname;
-       int res = count;
+       int rv, res = count;
        struct bonding *bond;
        struct bonding *nxt;
 
-       down_write(&(bonding_rwsem));
        sscanf(buffer, "%16s", command); /* IFNAMSIZ*/
        ifname = command + 1;
        if ((strlen(command) <= 1) ||
@@ -122,69 +120,60 @@ static ssize_t bonding_store_bonds(struct class *cls, const char *buffer, size_t
                goto err_no_cmd;
 
        if (command[0] == '+') {
-
-               /* Check to see if the bond already exists. */
-               list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
-                       if (strnicmp(bond->dev->name, ifname, IFNAMSIZ) == 0) {
-                               printk(KERN_ERR DRV_NAME
-                                       ": cannot add bond %s; it already exists\n",
-                                       ifname);
-                               res = -EPERM;
-                               goto out;
-                       }
-
                printk(KERN_INFO DRV_NAME
                        ": %s is being created...\n", ifname);
-               if (bond_create(ifname, &bonding_defaults, &bond)) {
-                       printk(KERN_INFO DRV_NAME
-                       ": %s interface already exists. Bond creation failed.\n",
-                       ifname);
-                       res = -EPERM;
+               rv = bond_create(ifname, &bonding_defaults, &bond);
+               if (rv) {
+                       printk(KERN_INFO DRV_NAME ": Bond creation failed.\n");
+                       res = rv;
                }
                goto out;
        }
 
        if (command[0] == '-') {
+               rtnl_lock();
+               down_write(&bonding_rwsem);
+
                list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
                        if (strnicmp(bond->dev->name, ifname, IFNAMSIZ) == 0) {
-                               rtnl_lock();
                                /* check the ref count on the bond's kobject.
                                 * If it's > expected, then there's a file open,
                                 * and we have to fail.
                                 */
                                if (atomic_read(&bond->dev->dev.kobj.kref.refcount)
                                                        > expected_refcount){
-                                       rtnl_unlock();
                                        printk(KERN_INFO DRV_NAME
                                                ": Unable remove bond %s due to open references.\n",
                                                ifname);
                                        res = -EPERM;
-                                       goto out;
+                                       goto out_unlock;
                                }
                                printk(KERN_INFO DRV_NAME
                                        ": %s is being deleted...\n",
                                        bond->dev->name);
                                bond_destroy(bond);
-                               rtnl_unlock();
-                               goto out;
+                               goto out_unlock;
                        }
 
                printk(KERN_ERR DRV_NAME
                        ": unable to delete non-existent bond %s\n", ifname);
                res = -ENODEV;
-               goto out;
+               goto out_unlock;
        }
 
 err_no_cmd:
        printk(KERN_ERR DRV_NAME
                ": no command found in bonding_masters. Use +ifname or -ifname.\n");
-       res = -EPERM;
+       return -EPERM;
+
+out_unlock:
+       up_write(&bonding_rwsem);
+       rtnl_unlock();
 
        /* Always return either count or an error.  If you return 0, you'll
         * get called forever, which is bad.
         */
 out:
-       up_write(&(bonding_rwsem));
        return res;
 }
 /* class attribute for bond_masters file.  This ends up in /sys/class/net */
@@ -229,20 +218,20 @@ 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 */
                        if ((PAGE_SIZE - res) > 10)
                                res = PAGE_SIZE - 10;
-                       res += sprintf(buf + res, "++more++");
+                       res += sprintf(buf + res, "++more++ ");
                        break;
                }
                res += sprintf(buf + res, "%s ", slave->dev->name);
        }
-       read_unlock_bh(&bond->lock);
-       res += sprintf(buf + res, "\n");
-       res++;
+       read_unlock(&bond->lock);
+       if (res)
+               buf[res-1] = '\n'; /* eat the leftover space */
        return res;
 }
 
@@ -272,6 +261,9 @@ static ssize_t bonding_store_slaves(struct device *d,
 
        /* Note:  We can't hold bond->lock here, as bond_create grabs it. */
 
+       rtnl_lock();
+       down_write(&(bonding_rwsem));
+
        sscanf(buffer, "%16s", command); /* IFNAMSIZ*/
        ifname = command + 1;
        if ((strlen(command) <= 1) ||
@@ -282,18 +274,18 @@ 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);
@@ -337,12 +329,10 @@ static ssize_t bonding_store_slaves(struct device *d,
                                dev->mtu = bond->dev->mtu;
                        }
                }
-               rtnl_lock();
                res = bond_enslave(bond->dev, dev);
                bond_for_each_slave(bond, slave, i)
                        if (strnicmp(slave->dev->name, ifname, IFNAMSIZ) == 0)
                                slave->original_mtu = original_mtu;
-               rtnl_unlock();
                if (res) {
                        ret = res;
                }
@@ -351,6 +341,7 @@ static ssize_t bonding_store_slaves(struct device *d,
 
        if (command[0] == '-') {
                dev = NULL;
+               original_mtu = 0;
                bond_for_each_slave(bond, slave, i)
                        if (strnicmp(slave->dev->name, ifname, IFNAMSIZ) == 0) {
                                dev = slave->dev;
@@ -360,12 +351,10 @@ static ssize_t bonding_store_slaves(struct device *d,
                if (dev) {
                        printk(KERN_INFO DRV_NAME ": %s: Removing slave %s\n",
                                bond->dev->name, dev->name);
-                       rtnl_lock();
                        if (bond->setup_by_slave)
                                res = bond_release_and_destroy(bond->dev, dev);
                        else
                                res = bond_release(bond->dev, dev);
-                       rtnl_unlock();
                        if (res) {
                                ret = res;
                                goto out;
@@ -390,6 +379,8 @@ err_no_cmd:
        ret = -EPERM;
 
 out:
+       up_write(&(bonding_rwsem));
+       rtnl_unlock();
        return ret;
 }
 
@@ -406,7 +397,7 @@ static ssize_t bonding_show_mode(struct device *d,
 
        return sprintf(buf, "%s %d\n",
                        bond_mode_tbl[bond->params.mode].modename,
-                       bond->params.mode) + 1;
+                       bond->params.mode);
 }
 
 static ssize_t bonding_store_mode(struct device *d,
@@ -424,7 +415,7 @@ static ssize_t bonding_store_mode(struct device *d,
                goto out;
        }
 
-       new_value = bond_parse_parm((char *)buf, bond_mode_tbl);
+       new_value = bond_parse_parm(buf, bond_mode_tbl);
        if (new_value < 0)  {
                printk(KERN_ERR DRV_NAME
                       ": %s: Ignoring invalid mode value %.*s.\n",
@@ -457,20 +448,11 @@ static ssize_t bonding_show_xmit_hash(struct device *d,
                                      struct device_attribute *attr,
                                      char *buf)
 {
-       int count;
        struct bonding *bond = to_bond(d);
 
-       if ((bond->params.mode != BOND_MODE_XOR) &&
-           (bond->params.mode != BOND_MODE_8023AD)) {
-               // Not Applicable
-               count = sprintf(buf, "NA\n") + 1;
-       } else {
-               count = sprintf(buf, "%s %d\n",
-                       xmit_hashtype_tbl[bond->params.xmit_policy].modename,
-                       bond->params.xmit_policy) + 1;
-       }
-
-       return count;
+       return sprintf(buf, "%s %d\n",
+                      xmit_hashtype_tbl[bond->params.xmit_policy].modename,
+                      bond->params.xmit_policy);
 }
 
 static ssize_t bonding_store_xmit_hash(struct device *d,
@@ -488,16 +470,7 @@ static ssize_t bonding_store_xmit_hash(struct device *d,
                goto out;
        }
 
-       if ((bond->params.mode != BOND_MODE_XOR) &&
-           (bond->params.mode != BOND_MODE_8023AD)) {
-               printk(KERN_ERR DRV_NAME
-                      "%s: Transmit hash policy is irrelevant in this mode.\n",
-                      bond->dev->name);
-               ret = -EPERM;
-               goto out;
-       }
-
-       new_value = bond_parse_parm((char *)buf, xmit_hashtype_tbl);
+       new_value = bond_parse_parm(buf, xmit_hashtype_tbl);
        if (new_value < 0)  {
                printk(KERN_ERR DRV_NAME
                       ": %s: Ignoring invalid xmit hash policy value %.*s.\n",
@@ -527,7 +500,7 @@ static ssize_t bonding_show_arp_validate(struct device *d,
 
        return sprintf(buf, "%s %d\n",
                       arp_validate_tbl[bond->params.arp_validate].modename,
-                      bond->params.arp_validate) + 1;
+                      bond->params.arp_validate);
 }
 
 static ssize_t bonding_store_arp_validate(struct device *d,
@@ -537,7 +510,7 @@ static ssize_t bonding_store_arp_validate(struct device *d,
        int new_value;
        struct bonding *bond = to_bond(d);
 
-       new_value = bond_parse_parm((char *)buf, arp_validate_tbl);
+       new_value = bond_parse_parm(buf, arp_validate_tbl);
        if (new_value < 0) {
                printk(KERN_ERR DRV_NAME
                       ": %s: Ignoring invalid arp_validate value %s\n",
@@ -627,7 +600,7 @@ static ssize_t bonding_show_arp_interval(struct device *d,
 {
        struct bonding *bond = to_bond(d);
 
-       return sprintf(buf, "%d\n", bond->params.arp_interval) + 1;
+       return sprintf(buf, "%d\n", bond->params.arp_interval);
 }
 
 static ssize_t bonding_store_arp_interval(struct device *d,
@@ -712,9 +685,7 @@ static ssize_t bonding_show_arp_targets(struct device *d,
                               NIPQUAD(bond->params.arp_targets[i]));
        }
        if (res)
-               res--;  /* eat the leftover space */
-       res += sprintf(buf + res, "\n");
-       res++;
+               buf[res-1] = '\n'; /* eat the leftover space */
        return res;
 }
 
@@ -815,7 +786,7 @@ static ssize_t bonding_show_downdelay(struct device *d,
 {
        struct bonding *bond = to_bond(d);
 
-       return sprintf(buf, "%d\n", bond->params.downdelay * bond->params.miimon) + 1;
+       return sprintf(buf, "%d\n", bond->params.downdelay * bond->params.miimon);
 }
 
 static ssize_t bonding_store_downdelay(struct device *d,
@@ -872,7 +843,7 @@ static ssize_t bonding_show_updelay(struct device *d,
 {
        struct bonding *bond = to_bond(d);
 
-       return sprintf(buf, "%d\n", bond->params.updelay * bond->params.miimon) + 1;
+       return sprintf(buf, "%d\n", bond->params.updelay * bond->params.miimon);
 
 }
 
@@ -936,7 +907,7 @@ static ssize_t bonding_show_lacp(struct device *d,
 
        return sprintf(buf, "%s %d\n",
                bond_lacp_tbl[bond->params.lacp_fast].modename,
-               bond->params.lacp_fast) + 1;
+               bond->params.lacp_fast);
 }
 
 static ssize_t bonding_store_lacp(struct device *d,
@@ -962,7 +933,7 @@ static ssize_t bonding_store_lacp(struct device *d,
                goto out;
        }
 
-       new_value = bond_parse_parm((char *)buf, bond_lacp_tbl);
+       new_value = bond_parse_parm(buf, bond_lacp_tbl);
 
        if ((new_value == 1) || (new_value == 0)) {
                bond->params.lacp_fast = new_value;
@@ -992,7 +963,7 @@ static ssize_t bonding_show_miimon(struct device *d,
 {
        struct bonding *bond = to_bond(d);
 
-       return sprintf(buf, "%d\n", bond->params.miimon) + 1;
+       return sprintf(buf, "%d\n", bond->params.miimon);
 }
 
 static ssize_t bonding_store_miimon(struct device *d,
@@ -1083,9 +1054,7 @@ static ssize_t bonding_show_primary(struct device *d,
        struct bonding *bond = to_bond(d);
 
        if (bond->primary_slave)
-               count = sprintf(buf, "%s\n", bond->primary_slave->dev->name) + 1;
-       else
-               count = sprintf(buf, "\n") + 1;
+               count = sprintf(buf, "%s\n", bond->primary_slave->dev->name);
 
        return count;
 }
@@ -1098,7 +1067,10 @@ static ssize_t bonding_store_primary(struct device *d,
        struct slave *slave;
        struct bonding *bond = to_bond(d);
 
-       write_lock_bh(&bond->lock);
+       rtnl_lock();
+       read_lock(&bond->lock);
+       write_lock_bh(&bond->curr_slave_lock);
+
        if (!USES_PRIMARY(bond->params.mode)) {
                printk(KERN_INFO DRV_NAME
                       ": %s: Unable to set primary slave; %s is in mode %d\n",
@@ -1132,7 +1104,10 @@ static ssize_t bonding_store_primary(struct device *d,
                }
        }
 out:
-       write_unlock_bh(&bond->lock);
+       write_unlock_bh(&bond->curr_slave_lock);
+       read_unlock(&bond->lock);
+       rtnl_unlock();
+
        return count;
 }
 static DEVICE_ATTR(primary, S_IRUGO | S_IWUSR, bonding_show_primary, bonding_store_primary);
@@ -1146,7 +1121,7 @@ static ssize_t bonding_show_carrier(struct device *d,
 {
        struct bonding *bond = to_bond(d);
 
-       return sprintf(buf, "%d\n", bond->params.use_carrier) + 1;
+       return sprintf(buf, "%d\n", bond->params.use_carrier);
 }
 
 static ssize_t bonding_store_carrier(struct device *d,
@@ -1188,17 +1163,14 @@ static ssize_t bonding_show_active_slave(struct device *d,
 {
        struct slave *curr;
        struct bonding *bond = to_bond(d);
-       int count;
-
+       int count = 0;
 
        read_lock(&bond->curr_slave_lock);
        curr = bond->curr_active_slave;
        read_unlock(&bond->curr_slave_lock);
 
        if (USES_PRIMARY(bond->params.mode) && curr)
-               count = sprintf(buf, "%s\n", curr->dev->name) + 1;
-       else
-               count = sprintf(buf, "\n") + 1;
+               count = sprintf(buf, "%s\n", curr->dev->name);
        return count;
 }
 
@@ -1212,7 +1184,10 @@ static ssize_t bonding_store_active_slave(struct device *d,
         struct slave *new_active = NULL;
        struct bonding *bond = to_bond(d);
 
-       write_lock_bh(&bond->lock);
+       rtnl_lock();
+       read_lock(&bond->lock);
+       write_lock_bh(&bond->curr_slave_lock);
+
        if (!USES_PRIMARY(bond->params.mode)) {
                printk(KERN_INFO DRV_NAME
                       ": %s: Unable to change active slave; %s is in mode %d\n",
@@ -1268,7 +1243,10 @@ static ssize_t bonding_store_active_slave(struct device *d,
                }
        }
 out:
-       write_unlock_bh(&bond->lock);
+       write_unlock_bh(&bond->curr_slave_lock);
+       read_unlock(&bond->lock);
+       rtnl_unlock();
+
        return count;
 
 }
@@ -1289,7 +1267,7 @@ static ssize_t bonding_show_mii_status(struct device *d,
        curr = bond->curr_active_slave;
        read_unlock(&bond->curr_slave_lock);
 
-       return sprintf(buf, "%s\n", (curr) ? "up" : "down") + 1;
+       return sprintf(buf, "%s\n", (curr) ? "up" : "down");
 }
 static DEVICE_ATTR(mii_status, S_IRUGO, bonding_show_mii_status, NULL);
 
@@ -1306,10 +1284,8 @@ static ssize_t bonding_show_ad_aggregator(struct device *d,
 
        if (bond->params.mode == BOND_MODE_8023AD) {
                struct ad_info ad_info;
-               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0 : ad_info.aggregator_id) + 1;
+               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0 : ad_info.aggregator_id);
        }
-       else
-               count = sprintf(buf, "\n") + 1;
 
        return count;
 }
@@ -1328,10 +1304,8 @@ static ssize_t bonding_show_ad_num_ports(struct device *d,
 
        if (bond->params.mode == BOND_MODE_8023AD) {
                struct ad_info ad_info;
-               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0: ad_info.ports) + 1;
+               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0: ad_info.ports);
        }
-       else
-               count = sprintf(buf, "\n") + 1;
 
        return count;
 }
@@ -1350,10 +1324,8 @@ static ssize_t bonding_show_ad_actor_key(struct device *d,
 
        if (bond->params.mode == BOND_MODE_8023AD) {
                struct ad_info ad_info;
-               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0 : ad_info.actor_key) + 1;
+               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0 : ad_info.actor_key);
        }
-       else
-               count = sprintf(buf, "\n") + 1;
 
        return count;
 }
@@ -1372,10 +1344,8 @@ static ssize_t bonding_show_ad_partner_key(struct device *d,
 
        if (bond->params.mode == BOND_MODE_8023AD) {
                struct ad_info ad_info;
-               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0 : ad_info.partner_key) + 1;
+               count = sprintf(buf, "%d\n", (bond_3ad_get_active_agg_info(bond, &ad_info)) ?  0 : ad_info.partner_key);
        }
-       else
-               count = sprintf(buf, "\n") + 1;
 
        return count;
 }
@@ -1397,12 +1367,9 @@ static ssize_t bonding_show_ad_partner_mac(struct device *d,
                struct ad_info ad_info;
                if (!bond_3ad_get_active_agg_info(bond, &ad_info)) {
                        count = sprintf(buf,"%s\n",
-                                       print_mac(mac, ad_info.partner_system))
-                               + 1;
+                                       print_mac(mac, ad_info.partner_system));
                }
        }
-       else
-               count = sprintf(buf, "\n") + 1;
 
        return count;
 }
@@ -1448,8 +1415,6 @@ int bond_create_sysfs(void)
        int ret = 0;
        struct bonding *firstbond;
 
-       init_rwsem(&bonding_rwsem);
-
        /* get the netdev class pointer */
        firstbond = container_of(bond_dev_list.next, struct bonding, bond_list);
        if (!firstbond)
@@ -1472,8 +1437,16 @@ int bond_create_sysfs(void)
         * configure multiple bonding devices.
         */
        if (ret == -EEXIST) {
-               netdev_class = NULL;
-               return 0;
+               /* Is someone being kinky and naming a device bonding_master? */
+               if (__dev_get_by_name(&init_net,
+                                     class_attr_bonding_masters.attr.name))
+                       printk(KERN_ERR
+                              "network device named %s already exists in sysfs",
+                              class_attr_bonding_masters.attr.name);
+               else {
+                       netdev_class = NULL;
+                       return 0;
+               }
        }
 
        return ret;