team: implement multipart netlink messages for options transfers

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index bc76f94..9e9d3e5 100644 (file)
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1571,102 +1571,128 @@ err_fill:
        return err;
 }
 
+typedef int team_nl_send_func_t(struct sk_buff *skb,
+                               struct team *team, u32 pid);
+
+static int team_nl_send_unicast(struct sk_buff *skb, struct team *team, u32 pid)
+{
+       return genlmsg_unicast(dev_net(team->dev), skb, pid);
+}
+
 static int team_nl_fill_one_option_get(struct sk_buff *skb, struct team *team,
                                       struct team_option_inst *opt_inst)
 {
        struct nlattr *option_item;
        struct team_option *option = opt_inst->option;
-       struct team_option_inst_info *opt_inst_info;
+       struct team_option_inst_info *opt_inst_info = &opt_inst->info;
        struct team_gsetter_ctx ctx;
        int err;
 
+       ctx.info = opt_inst_info;
+       err = team_option_get(team, opt_inst, &ctx);
+       if (err)
+               return err;
+
        option_item = nla_nest_start(skb, TEAM_ATTR_ITEM_OPTION);
        if (!option_item)
-               goto nla_put_failure;
-       if (nla_put_string(skb, TEAM_ATTR_OPTION_NAME, option->name))
-               goto nla_put_failure;
-       if (opt_inst->changed) {
-               if (nla_put_flag(skb, TEAM_ATTR_OPTION_CHANGED))
-                       goto nla_put_failure;
-               opt_inst->changed = false;
-       }
-       if (opt_inst->removed && nla_put_flag(skb, TEAM_ATTR_OPTION_REMOVED))
-               goto nla_put_failure;
+               return -EMSGSIZE;
 
-       opt_inst_info = &opt_inst->info;
+       if (nla_put_string(skb, TEAM_ATTR_OPTION_NAME, option->name))
+               goto nest_cancel;
        if (opt_inst_info->port &&
            nla_put_u32(skb, TEAM_ATTR_OPTION_PORT_IFINDEX,
                        opt_inst_info->port->dev->ifindex))
-               goto nla_put_failure;
+               goto nest_cancel;
        if (opt_inst->option->array_size &&
            nla_put_u32(skb, TEAM_ATTR_OPTION_ARRAY_INDEX,
                        opt_inst_info->array_index))
-               goto nla_put_failure;
-       ctx.info = opt_inst_info;
+               goto nest_cancel;
 
        switch (option->type) {
        case TEAM_OPTION_TYPE_U32:
                if (nla_put_u8(skb, TEAM_ATTR_OPTION_TYPE, NLA_U32))
-                       goto nla_put_failure;
-               err = team_option_get(team, opt_inst, &ctx);
-               if (err)
-                       goto errout;
+                       goto nest_cancel;
                if (nla_put_u32(skb, TEAM_ATTR_OPTION_DATA, ctx.data.u32_val))
-                       goto nla_put_failure;
+                       goto nest_cancel;
                break;
        case TEAM_OPTION_TYPE_STRING:
                if (nla_put_u8(skb, TEAM_ATTR_OPTION_TYPE, NLA_STRING))
-                       goto nla_put_failure;
-               err = team_option_get(team, opt_inst, &ctx);
-               if (err)
-                       goto errout;
+                       goto nest_cancel;
                if (nla_put_string(skb, TEAM_ATTR_OPTION_DATA,
                                   ctx.data.str_val))
-                       goto nla_put_failure;
+                       goto nest_cancel;
                break;
        case TEAM_OPTION_TYPE_BINARY:
                if (nla_put_u8(skb, TEAM_ATTR_OPTION_TYPE, NLA_BINARY))
-                       goto nla_put_failure;
-               err = team_option_get(team, opt_inst, &ctx);
-               if (err)
-                       goto errout;
+                       goto nest_cancel;
                if (nla_put(skb, TEAM_ATTR_OPTION_DATA, ctx.data.bin_val.len,
                            ctx.data.bin_val.ptr))
-                       goto nla_put_failure;
+                       goto nest_cancel;
                break;
        case TEAM_OPTION_TYPE_BOOL:
                if (nla_put_u8(skb, TEAM_ATTR_OPTION_TYPE, NLA_FLAG))
-                       goto nla_put_failure;
-               err = team_option_get(team, opt_inst, &ctx);
-               if (err)
-                       goto errout;
+                       goto nest_cancel;
                if (ctx.data.bool_val &&
                    nla_put_flag(skb, TEAM_ATTR_OPTION_DATA))
-                       goto nla_put_failure;
+                       goto nest_cancel;
                break;
        default:
                BUG();
        }
+       if (opt_inst->removed && nla_put_flag(skb, TEAM_ATTR_OPTION_REMOVED))
+               goto nest_cancel;
+       if (opt_inst->changed) {
+               if (nla_put_flag(skb, TEAM_ATTR_OPTION_CHANGED))
+                       goto nest_cancel;
+               opt_inst->changed = false;
+       }
        nla_nest_end(skb, option_item);
        return 0;
 
-nla_put_failure:
-       err = -EMSGSIZE;
-errout:
-       return err;
+nest_cancel:
+       nla_nest_cancel(skb, option_item);
+       return -EMSGSIZE;
+}
+
+static int __send_and_alloc_skb(struct sk_buff **pskb,
+                               struct team *team, u32 pid,
+                               team_nl_send_func_t *send_func)
+{
+       int err;
+
+       if (*pskb) {
+               err = send_func(*pskb, team, pid);
+               if (err)
+                       return err;
+       }
+       *pskb = genlmsg_new(NLMSG_DEFAULT_SIZE - GENL_HDRLEN, GFP_KERNEL);
+       if (!*pskb)
+               return -ENOMEM;
+       return 0;
 }
 
-static int team_nl_fill_options_get(struct sk_buff *skb,
-                                   u32 pid, u32 seq, int flags,
-                                   struct team *team,
+static int team_nl_send_options_get(struct team *team, u32 pid, u32 seq,
+                                   int flags, team_nl_send_func_t *send_func,
                                    struct list_head *sel_opt_inst_list)
 {
        struct nlattr *option_list;
+       struct nlmsghdr *nlh;
        void *hdr;
        struct team_option_inst *opt_inst;
        int err;
+       struct sk_buff *skb = NULL;
+       bool incomplete;
+       int i;
 
-       hdr = genlmsg_put(skb, pid, seq, &team_nl_family, flags,
+       opt_inst = list_first_entry(sel_opt_inst_list,
+                                   struct team_option_inst, tmp_list);
+
+start_again:
+       err = __send_and_alloc_skb(&skb, team, pid, send_func);
+       if (err)
+               return err;
+
+       hdr = genlmsg_put(skb, pid, seq, &team_nl_family, flags | NLM_F_MULTI,
                          TEAM_CMD_OPTIONS_GET);
        if (IS_ERR(hdr))
                return PTR_ERR(hdr);
@@ -1677,46 +1703,62 @@ static int team_nl_fill_options_get(struct sk_buff *skb,
        if (!option_list)
                goto nla_put_failure;
 
-       list_for_each_entry(opt_inst, sel_opt_inst_list, tmp_list) {
+       i = 0;
+       incomplete = false;
+       list_for_each_entry_from(opt_inst, sel_opt_inst_list, tmp_list) {
                err = team_nl_fill_one_option_get(skb, team, opt_inst);
-               if (err)
+               if (err) {
+                       if (err == -EMSGSIZE) {
+                               if (!i)
+                                       goto errout;
+                               incomplete = true;
+                               break;
+                       }
                        goto errout;
+               }
+               i++;
        }
 
        nla_nest_end(skb, option_list);
-       return genlmsg_end(skb, hdr);
+       genlmsg_end(skb, hdr);
+       if (incomplete)
+               goto start_again;
+
+send_done:
+       nlh = nlmsg_put(skb, pid, seq, NLMSG_DONE, 0, flags | NLM_F_MULTI);
+       if (!nlh) {
+               err = __send_and_alloc_skb(&skb, team, pid, send_func);
+               if (err)
+                       goto errout;
+               goto send_done;
+       }
+
+       return send_func(skb, team, pid);
 
 nla_put_failure:
        err = -EMSGSIZE;
 errout:
        genlmsg_cancel(skb, hdr);
+       nlmsg_free(skb);
        return err;
 }
 
-static int team_nl_fill_options_get_all(struct sk_buff *skb,
-                                       struct genl_info *info, int flags,
-                                       struct team *team)
-{
-       struct team_option_inst *opt_inst;
-       LIST_HEAD(sel_opt_inst_list);
-
-       list_for_each_entry(opt_inst, &team->option_inst_list, list)
-               list_add_tail(&opt_inst->tmp_list, &sel_opt_inst_list);
-       return team_nl_fill_options_get(skb, info->snd_pid,
-                                       info->snd_seq, NLM_F_ACK,
-                                       team, &sel_opt_inst_list);
-}
-
 static int team_nl_cmd_options_get(struct sk_buff *skb, struct genl_info *info)
 {
        struct team *team;
+       struct team_option_inst *opt_inst;
        int err;
+       LIST_HEAD(sel_opt_inst_list);
 
        team = team_nl_team_get(info);
        if (!team)
                return -EINVAL;
 
-       err = team_nl_send_generic(info, team, team_nl_fill_options_get_all);
+       list_for_each_entry(opt_inst, &team->option_inst_list, list)
+               list_add_tail(&opt_inst->tmp_list, &sel_opt_inst_list);
+       err = team_nl_send_options_get(team, info->snd_pid, info->snd_seq,
+                                      NLM_F_ACK, team_nl_send_unicast,
+                                      &sel_opt_inst_list);
 
        team_nl_team_put(team);
 
@@ -1963,28 +2005,18 @@ static struct genl_multicast_group team_change_event_mcgrp = {
        .name = TEAM_GENL_CHANGE_EVENT_MC_GRP_NAME,
 };
 
+static int team_nl_send_multicast(struct sk_buff *skb,
+                                 struct team *team, u32 pid)
+{
+       return genlmsg_multicast_netns(dev_net(team->dev), skb, 0,
+                                      team_change_event_mcgrp.id, GFP_KERNEL);
+}
+
 static int team_nl_send_event_options_get(struct team *team,
                                          struct list_head *sel_opt_inst_list)
 {
-       struct sk_buff *skb;
-       int err;
-       struct net *net = dev_net(team->dev);
-
-       skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
-       if (!skb)
-               return -ENOMEM;
-
-       err = team_nl_fill_options_get(skb, 0, 0, 0, team, sel_opt_inst_list);
-       if (err < 0)
-               goto err_fill;
-
-       err = genlmsg_multicast_netns(net, skb, 0, team_change_event_mcgrp.id,
-                                     GFP_KERNEL);
-       return err;
-
-err_fill:
-       nlmsg_free(skb);
-       return err;
+       return team_nl_send_options_get(team, 0, 0, 0, team_nl_send_multicast,
+                                       sel_opt_inst_list);
 }
 
 static int team_nl_send_event_port_list_get(struct team *team)
@@ -2053,7 +2085,8 @@ static void __team_options_change_check(struct team *team)
        }
        err = team_nl_send_event_options_get(team, &sel_opt_inst_list);
        if (err)
-               netdev_warn(team->dev, "Failed to send options change via netlink\n");
+               netdev_warn(team->dev, "Failed to send options change via netlink (err %d)\n",
+                           err);
 }
 
 static void __team_option_inst_change(struct team *team,
@@ -2066,7 +2099,8 @@ static void __team_option_inst_change(struct team *team,
        list_add(&sel_opt_inst->tmp_list, &sel_opt_inst_list);
        err = team_nl_send_event_options_get(team, &sel_opt_inst_list);
        if (err)
-               netdev_warn(team->dev, "Failed to send option change via netlink\n");
+               netdev_warn(team->dev, "Failed to send option change via netlink (err %d)\n",
+                           err);
 }
 
 /* rtnl lock is held */