datapath: Prepare to support 32-bit compatibility ioctls.

This commit prepares the core of datapath.c and vport.c to reduce the
amount of new code duplication when the following commit adds support for
32-bit compatibility ioctls.  It breaks a number of functions apart into
pairs of functions: one that copies data to and from userspace and another
that does the real work.

This change is a pure refactoring that should not change behavior.

diff --git a/datapath/datapath.c b/datapath/datapath.c
index eec998c..475baa4 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -960,28 +960,24 @@ static int expand_table(struct datapath *dp)
        return 0;
 }
 
-static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp)
+static int do_put_flow(struct datapath *dp, struct odp_flow_put *uf,
+                      struct odp_flow_stats *stats)
 {
-       struct odp_flow_put uf;
        struct tbl_node *flow_node;
        struct sw_flow *flow;
        struct tbl *table;
-       struct odp_flow_stats stats;
        int error;
 
-       error = -EFAULT;
-       if (copy_from_user(&uf, ufp, sizeof(struct odp_flow_put)))
-               goto error;
-       memset(uf.flow.key.reserved, 0, sizeof uf.flow.key.reserved);
+       memset(uf->flow.key.reserved, 0, sizeof uf->flow.key.reserved);
 
        table = rcu_dereference(dp->table);
-       flow_node = tbl_lookup(table, &uf.flow.key, flow_hash(&uf.flow.key), flow_cmp);
+       flow_node = tbl_lookup(table, &uf->flow.key, flow_hash(&uf->flow.key), flow_cmp);
        if (!flow_node) {
                /* No such flow. */
                struct sw_flow_actions *acts;
 
                error = -ENOENT;
-               if (!(uf.flags & ODPPF_CREATE))
+               if (!(uf->flags & ODPPF_CREATE))
                        goto error;
 
                /* Expand table, if necessary, to make room. */
@@ -997,12 +993,12 @@ static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp)
                flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
                if (flow == NULL)
                        goto error;
-               flow->key = uf.flow.key;
+               flow->key = uf->flow.key;
                spin_lock_init(&flow->lock);
                clear_stats(flow);
 
                /* Obtain actions. */
-               acts = get_actions(&uf.flow);
+               acts = get_actions(&uf->flow);
                error = PTR_ERR(acts);
                if (IS_ERR(acts))
                        goto error_free_flow;
@@ -1013,7 +1009,7 @@ static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp)
                if (error)
                        goto error_free_flow_acts;
 
-               memset(&stats, 0, sizeof(struct odp_flow_stats));
+               memset(stats, 0, sizeof(struct odp_flow_stats));
        } else {
                /* We found a matching flow. */
                struct sw_flow_actions *old_acts, *new_acts;
@@ -1023,11 +1019,11 @@ static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp)
 
                /* Bail out if we're not allowed to modify an existing flow. */
                error = -EEXIST;
-               if (!(uf.flags & ODPPF_MODIFY))
+               if (!(uf->flags & ODPPF_MODIFY))
                        goto error;
 
                /* Swap actions. */
-               new_acts = get_actions(&uf.flow);
+               new_acts = get_actions(&uf->flow);
                error = PTR_ERR(new_acts);
                if (IS_ERR(new_acts))
                        goto error;
@@ -1043,16 +1039,12 @@ static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp)
 
                /* Fetch stats, then clear them if necessary. */
                spin_lock_irqsave(&flow->lock, flags);
-               get_stats(flow, &stats);
-               if (uf.flags & ODPPF_ZERO_STATS)
+               get_stats(flow, stats);
+               if (uf->flags & ODPPF_ZERO_STATS)
                        clear_stats(flow);
                spin_unlock_irqrestore(&flow->lock, flags);
        }
 
-       /* Copy stats to userspace. */
-       if (__copy_to_user(&ufp->flow.stats, &stats,
-                          sizeof(struct odp_flow_stats)))
-               return -EFAULT;
        return 0;
 
 error_free_flow_acts:
@@ -1063,21 +1055,52 @@ error:
        return error;
 }
 
-static int put_actions(const struct sw_flow *flow, struct odp_flow __user *ufp)
+static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp)
+{
+       struct odp_flow_stats stats;
+       struct odp_flow_put uf;
+       int error;
+
+       if (copy_from_user(&uf, ufp, sizeof(struct odp_flow_put)))
+               return -EFAULT;
+
+       error = do_put_flow(dp, &uf, &stats);
+       if (error)
+               return error;
+
+       if (__copy_to_user(&ufp->flow.stats, &stats,
+                          sizeof(struct odp_flow_stats)))
+               return -EFAULT;
+
+       return 0;
+}
+
+static int do_answer_query(struct sw_flow *flow, u32 query_flags,
+                          struct odp_flow_stats __user *ustats,
+                          union odp_action __user *actions,
+                          u32 __user *n_actionsp)
 {
-       union odp_action __user *actions;
        struct sw_flow_actions *sf_acts;
+       struct odp_flow_stats stats;
+       unsigned long int flags;
        u32 n_actions;
 
-       if (__get_user(actions, &ufp->actions) ||
-           __get_user(n_actions, &ufp->n_actions))
+       spin_lock_irqsave(&flow->lock, flags);
+       get_stats(flow, &stats);
+       if (query_flags & ODPFF_ZERO_TCP_FLAGS) {
+               flow->tcp_flags = 0;
+       }
+       spin_unlock_irqrestore(&flow->lock, flags);
+
+       if (__copy_to_user(ustats, &stats, sizeof(struct odp_flow_stats)) ||
+           __get_user(n_actions, n_actionsp))
                return -EFAULT;
 
        if (!n_actions)
                return 0;
 
        sf_acts = rcu_dereference(flow->sf_acts);
-       if (__put_user(sf_acts->n_actions, &ufp->n_actions) ||
+       if (__put_user(sf_acts->n_actions, n_actionsp) ||
            (actions && copy_to_user(actions, sf_acts->actions,
                                     sizeof(union odp_action) *
                                     min(sf_acts->n_actions, n_actions))))
@@ -1089,64 +1112,62 @@ static int put_actions(const struct sw_flow *flow, struct odp_flow __user *ufp)
 static int answer_query(struct sw_flow *flow, u32 query_flags,
                        struct odp_flow __user *ufp)
 {
-       struct odp_flow_stats stats;
-       unsigned long int flags;
-
-       spin_lock_irqsave(&flow->lock, flags);
-       get_stats(flow, &stats);
-
-       if (query_flags & ODPFF_ZERO_TCP_FLAGS) {
-               flow->tcp_flags = 0;
-       }
-       spin_unlock_irqrestore(&flow->lock, flags);
+       union odp_action *actions;
 
-       if (__copy_to_user(&ufp->stats, &stats, sizeof(struct odp_flow_stats)))
+       if (__get_user(actions, &ufp->actions))
                return -EFAULT;
-       return put_actions(flow, ufp);
+
+       return do_answer_query(flow, query_flags,
+                              &ufp->stats, actions, &ufp->n_actions);
 }
 
-static int del_flow(struct datapath *dp, struct odp_flow __user *ufp)
+static struct sw_flow *do_del_flow(struct datapath *dp, struct odp_flow_key *key)
 {
        struct tbl *table = rcu_dereference(dp->table);
-       struct odp_flow uf;
        struct tbl_node *flow_node;
-       struct sw_flow *flow;
        int error;
 
-       error = -EFAULT;
-       if (copy_from_user(&uf, ufp, sizeof uf))
-               goto error;
-       memset(uf.key.reserved, 0, sizeof uf.key.reserved);
-
-       flow_node = tbl_lookup(table, &uf.key, flow_hash(&uf.key), flow_cmp);
-       error = -ENOENT;
+       memset(key->reserved, 0, sizeof key->reserved);
+       flow_node = tbl_lookup(table, key, flow_hash(key), flow_cmp);
        if (!flow_node)
-               goto error;
+               return ERR_PTR(-ENOENT);
 
        error = tbl_remove(table, flow_node);
        if (error)
-               goto error;
+               return ERR_PTR(error);
 
-       /* XXX These statistics might lose a few packets, since other CPUs can
-        * be using this flow.  We used to synchronize_rcu() to make sure that
-        * we get completely accurate stats, but that blows our performance,
-        * badly. */
+       /* XXX Returned flow_node's statistics might lose a few packets, since
+        * other CPUs can be using this flow.  We used to synchronize_rcu() to
+        * make sure that we get completely accurate stats, but that blows our
+        * performance, badly. */
+       return flow_cast(flow_node);
+}
+
+static int del_flow(struct datapath *dp, struct odp_flow __user *ufp)
+{
+       struct sw_flow *flow;
+       struct odp_flow uf;
+       int error;
+
+       if (copy_from_user(&uf, ufp, sizeof uf))
+               return -EFAULT;
+
+       flow = do_del_flow(dp, &uf.key);
+       if (IS_ERR(flow))
+               return PTR_ERR(flow);
 
-       flow = flow_cast(flow_node);
        error = answer_query(flow, 0, ufp);
        flow_deferred_free(flow);
-
-error:
        return error;
 }
 
-static int query_flows(struct datapath *dp, const struct odp_flowvec *flowvec)
+static int do_query_flows(struct datapath *dp, const struct odp_flowvec *flowvec)
 {
        struct tbl *table = rcu_dereference(dp->table);
        u32 i;
 
        for (i = 0; i < flowvec->n_flows; i++) {
-               struct __user odp_flow *ufp = &flowvec->flows[i];
+               struct odp_flow __user *ufp = &flowvec->flows[i];
                struct odp_flow uf;
                struct tbl_node *flow_node;
                int error;
@@ -1190,7 +1211,7 @@ static int list_flow(struct tbl_node *node, void *cbdata_)
        return 0;
 }
 
-static int list_flows(struct datapath *dp, const struct odp_flowvec *flowvec)
+static int do_list_flows(struct datapath *dp, const struct odp_flowvec *flowvec)
 {
        struct list_flows_cbdata cbdata;
        int error;
@@ -1231,31 +1252,26 @@ static int do_flowvec_ioctl(struct datapath *dp, unsigned long argp,
                : __put_user(retval, &uflowvec->n_flows));
 }
 
-static int do_execute(struct datapath *dp, const struct odp_execute *executep)
+static int do_execute(struct datapath *dp, const struct odp_execute *execute)
 {
-       struct odp_execute execute;
        struct odp_flow_key key;
        struct sk_buff *skb;
        struct sw_flow_actions *actions;
        struct ethhdr *eth;
        int err;
 
-       err = -EFAULT;
-       if (copy_from_user(&execute, executep, sizeof execute))
-               goto error;
-
        err = -EINVAL;
-       if (execute.length < ETH_HLEN || execute.length > 65535)
+       if (execute->length < ETH_HLEN || execute->length > 65535)
                goto error;
 
        err = -ENOMEM;
-       actions = flow_actions_alloc(execute.n_actions);
+       actions = flow_actions_alloc(execute->n_actions);
        if (!actions)
                goto error;
 
        err = -EFAULT;
-       if (copy_from_user(actions->actions, execute.actions,
-                          execute.n_actions * sizeof *execute.actions))
+       if (copy_from_user(actions->actions, execute->actions,
+                          execute->n_actions * sizeof *execute->actions))
                goto error_free_actions;
 
        err = validate_actions(actions);
@@ -1263,18 +1279,18 @@ static int do_execute(struct datapath *dp, const struct odp_execute *executep)
                goto error_free_actions;
 
        err = -ENOMEM;
-       skb = alloc_skb(execute.length, GFP_KERNEL);
+       skb = alloc_skb(execute->length, GFP_KERNEL);
        if (!skb)
                goto error_free_actions;
 
-       if (execute.in_port < DP_MAX_PORTS)
-               OVS_CB(skb)->dp_port = dp->ports[execute.in_port];
+       if (execute->in_port < DP_MAX_PORTS)
+               OVS_CB(skb)->dp_port = dp->ports[execute->in_port];
        else
                OVS_CB(skb)->dp_port = NULL;
 
        err = -EFAULT;
-       if (copy_from_user(skb_put(skb, execute.length), execute.data,
-                          execute.length))
+       if (copy_from_user(skb_put(skb, execute->length), execute->data,
+                          execute->length))
                goto error_free_skb;
 
        skb_reset_mac_header(skb);
@@ -1288,7 +1304,7 @@ static int do_execute(struct datapath *dp, const struct odp_execute *executep)
        else
                skb->protocol = htons(ETH_P_802_2);
 
-       flow_extract(skb, execute.in_port, &key);
+       flow_extract(skb, execute->in_port, &key);
        err = execute_actions(dp, skb, &key, actions->actions,
                              actions->n_actions, GFP_KERNEL);
        kfree(actions);
@@ -1302,6 +1318,16 @@ error:
        return err;
 }
 
+static int execute_packet(struct datapath *dp, const struct odp_execute __user *executep)
+{
+       struct odp_execute execute;
+
+       if (copy_from_user(&execute, executep, sizeof execute))
+               return -EFAULT;
+
+       return do_execute(dp, &execute);
+}
+
 static int get_dp_stats(struct datapath *dp, struct odp_stats __user *statsp)
 {
        struct tbl *table = rcu_dereference(dp->table);
@@ -1435,25 +1461,36 @@ error_unlock:
 }
 
 static int
-list_ports(struct datapath *dp, struct odp_portvec __user *pvp)
+do_list_ports(struct datapath *dp, struct odp_port __user *uports, int n_ports)
 {
-       struct odp_portvec pv;
-       struct dp_port *p;
-       int idx;
-
-       if (copy_from_user(&pv, pvp, sizeof pv))
-               return -EFAULT;
+       int idx = 0;
+       if (n_ports) {
+               struct dp_port *p;
 
-       idx = 0;
-       if (pv.n_ports) {
                list_for_each_entry_rcu (p, &dp->port_list, node) {
-                       if (put_port(p, &pv.ports[idx]))
+                       if (put_port(p, &uports[idx]))
                                return -EFAULT;
-                       if (idx++ >= pv.n_ports)
+                       if (idx++ >= n_ports)
                                break;
                }
        }
-       return put_user(dp->n_ports, &pvp->n_ports);
+       return idx;
+}
+
+static int
+list_ports(struct datapath *dp, struct odp_portvec __user *upv)
+{
+       struct odp_portvec pv;
+       int retval;
+
+       if (copy_from_user(&pv, upv, sizeof pv))
+               return -EFAULT;
+
+       retval = do_list_ports(dp, pv.ports, pv.n_ports);
+       if (retval < 0)
+               return retval;
+
+       return put_user(retval, &upv->n_ports);
 }
 
 /* RCU callback for freeing a dp_port_group */
@@ -1464,34 +1501,27 @@ static void free_port_group(struct rcu_head *rcu)
 }
 
 static int
-set_port_group(struct datapath *dp, const struct odp_port_group __user *upg)
+do_set_port_group(struct datapath *dp, u16 __user *ports, int n_ports, int group)
 {
-       struct odp_port_group pg;
        struct dp_port_group *new_group, *old_group;
        int error;
 
-       error = -EFAULT;
-       if (copy_from_user(&pg, upg, sizeof pg))
-               goto error;
-
        error = -EINVAL;
-       if (pg.n_ports > DP_MAX_PORTS || pg.group >= DP_MAX_GROUPS)
+       if (n_ports > DP_MAX_PORTS || group >= DP_MAX_GROUPS)
                goto error;
 
        error = -ENOMEM;
-       new_group = kmalloc(sizeof *new_group + sizeof(u16) * pg.n_ports,
-                           GFP_KERNEL);
+       new_group = kmalloc(sizeof *new_group + sizeof(u16) * n_ports, GFP_KERNEL);
        if (!new_group)
                goto error;
 
-       new_group->n_ports = pg.n_ports;
+       new_group->n_ports = n_ports;
        error = -EFAULT;
-       if (copy_from_user(new_group->ports, pg.ports,
-                          sizeof(u16) * pg.n_ports))
+       if (copy_from_user(new_group->ports, ports, sizeof(u16) * n_ports))
                goto error_free;
 
-       old_group = rcu_dereference(dp->groups[pg.group]);
-       rcu_assign_pointer(dp->groups[pg.group], new_group);
+       old_group = rcu_dereference(dp->groups[group]);
+       rcu_assign_pointer(dp->groups[group], new_group);
        if (old_group)
                call_rcu(&old_group->rcu, free_port_group);
        return 0;
@@ -1503,29 +1533,48 @@ error:
 }
 
 static int
-get_port_group(struct datapath *dp, struct odp_port_group *upg)
+set_port_group(struct datapath *dp, const struct odp_port_group __user *upg)
 {
        struct odp_port_group pg;
-       struct dp_port_group *g;
-       u16 n_copy;
 
        if (copy_from_user(&pg, upg, sizeof pg))
                return -EFAULT;
 
-       if (pg.group >= DP_MAX_GROUPS)
+       return do_set_port_group(dp, pg.ports, pg.n_ports, pg.group);
+}
+
+static int
+do_get_port_group(struct datapath *dp,
+                 u16 __user *ports, int n_ports, int group,
+                 u16 __user *n_portsp)
+{
+       struct dp_port_group *g;
+       u16 n_copy;
+
+       if (group >= DP_MAX_GROUPS)
                return -EINVAL;
 
-       g = dp->groups[pg.group];
-       n_copy = g ? min_t(int, g->n_ports, pg.n_ports) : 0;
-       if (n_copy && copy_to_user(pg.ports, g->ports, n_copy * sizeof(u16)))
+       g = dp->groups[group];
+       n_copy = g ? min_t(int, g->n_ports, n_ports) : 0;
+       if (n_copy && copy_to_user(ports, g->ports, n_copy * sizeof(u16)))
                return -EFAULT;
 
-       if (put_user(g ? g->n_ports : 0, &upg->n_ports))
+       if (put_user(g ? g->n_ports : 0, n_portsp))
                return -EFAULT;
 
        return 0;
 }
 
+static int get_port_group(struct datapath *dp, struct odp_port_group __user *upg)
+{
+       struct odp_port_group pg;
+
+       if (copy_from_user(&pg, upg, sizeof pg))
+               return -EFAULT;
+
+       return do_get_port_group(dp, pg.ports, pg.n_ports, pg.group, &pg.n_ports);
+}
+
 static int get_listen_mask(const struct file *f)
 {
        return (long)f->private_data;
@@ -1677,15 +1726,15 @@ static long openvswitch_ioctl(struct file *f, unsigned int cmd,
                break;
 
        case ODP_FLOW_GET:
-               err = do_flowvec_ioctl(dp, argp, query_flows);
+               err = do_flowvec_ioctl(dp, argp, do_query_flows);
                break;
 
        case ODP_FLOW_LIST:
-               err = do_flowvec_ioctl(dp, argp, list_flows);
+               err = do_flowvec_ioctl(dp, argp, do_list_flows);
                break;
 
        case ODP_EXECUTE:
-               err = do_execute(dp, (struct odp_execute __user *)argp);
+               err = execute_packet(dp, (struct odp_execute __user *)argp);
                break;
 
        default:

diff --git a/datapath/vport.c b/datapath/vport.c
index 716a458..5656672 100644 (file)
--- a/datapath/vport.c
+++ b/datapath/vport.c
@@ -187,30 +187,26 @@ vport_exit(void)
  * on device type).  This function is for userspace callers and assumes no
  * locks are held.
  */
-int
-vport_add(const struct odp_vport_add __user *uvport_config)
+static int
+do_vport_add(struct odp_vport_add *vport_config)
 {
-       struct odp_vport_add vport_config;
        struct vport *vport;
        int err = 0;
 
-       if (copy_from_user(&vport_config, uvport_config, sizeof(struct odp_vport_add)))
-               return -EFAULT;
-
-       vport_config.port_type[VPORT_TYPE_SIZE - 1] = '\0';
-       vport_config.devname[IFNAMSIZ - 1] = '\0';
+       vport_config->port_type[VPORT_TYPE_SIZE - 1] = '\0';
+       vport_config->devname[IFNAMSIZ - 1] = '\0';
 
        rtnl_lock();
 
-       vport = vport_locate(vport_config.devname);
+       vport = vport_locate(vport_config->devname);
        if (vport) {
                err = -EEXIST;
                goto out;
        }
 
        vport_lock();
-       vport = __vport_add(vport_config.devname, vport_config.port_type,
-                           vport_config.config);
+       vport = __vport_add(vport_config->devname, vport_config->port_type,
+                           vport_config->config);
        vport_unlock();
 
        if (IS_ERR(vport))
@@ -221,6 +217,17 @@ out:
        return err;
 }
 
+int
+vport_add(const struct odp_vport_add __user *uvport_config)
+{
+       struct odp_vport_add vport_config;
+
+       if (copy_from_user(&vport_config, uvport_config, sizeof(struct odp_vport_add)))
+               return -EFAULT;
+
+       return do_vport_add(&vport_config);
+}
+
 /**
  *     vport_mod - modify existing vport device (for userspace callers)
  *
@@ -230,28 +237,24 @@ out:
  * dependent on device type).  This function is for userspace callers and
  * assumes no locks are held.
  */
-int
-vport_mod(const struct odp_vport_mod __user *uvport_config)
+static int
+do_vport_mod(struct odp_vport_mod *vport_config)
 {
-       struct odp_vport_mod vport_config;
        struct vport *vport;
        int err;
 
-       if (copy_from_user(&vport_config, uvport_config, sizeof(struct odp_vport_mod)))
-               return -EFAULT;
-
-       vport_config.devname[IFNAMSIZ - 1] = '\0';
+       vport_config->devname[IFNAMSIZ - 1] = '\0';
 
        rtnl_lock();
 
-       vport = vport_locate(vport_config.devname);
+       vport = vport_locate(vport_config->devname);
        if (!vport) {
                err = -ENODEV;
                goto out;
        }
 
        vport_lock();
-       err = __vport_mod(vport, vport_config.config);
+       err = __vport_mod(vport, vport_config->config);
        vport_unlock();
 
 out:
@@ -259,6 +262,17 @@ out:
        return err;
 }
 
+int
+vport_mod(const struct odp_vport_mod __user *uvport_config)
+{
+       struct odp_vport_mod vport_config;
+
+       if (copy_from_user(&vport_config, uvport_config, sizeof(struct odp_vport_mod)))
+               return -EFAULT;
+
+       return do_vport_mod(&vport_config);
+}
+
 /**
  *     vport_del - delete existing vport device (for userspace callers)
  *