tipc: add name table dump to new netlink api

Add TIPC_NL_NAME_TABLE_GET command to the new tipc netlink API.

This command supports dumping the name table of all nodes.

Netlink logical layout of name table response message:
-> name table
    -> publication
        -> type
        -> lower
        -> upper
        -> scope
        -> node
        -> ref
        -> key

Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 200 insertions, 3 deletions

diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index 3a6a0a7c0759..30ca8e0e0f84 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -1,7 +1,7 @@
 /*
  * net/tipc/name_table.c: TIPC name table code
  *
- * Copyright (c) 2000-2006, Ericsson AB
+ * Copyright (c) 2000-2006, 2014, Ericsson AB
  * Copyright (c) 2004-2008, 2010-2011, Wind River Systems
  * All rights reserved.
  *
@@ -42,6 +42,12 @@
 
 #define TIPC_NAMETBL_SIZE 1024          /* must be a power of 2 */
 
+static const struct nla_policy
+tipc_nl_name_table_policy[TIPC_NLA_NAME_TABLE_MAX + 1] = {
+        [TIPC_NLA_NAME_TABLE_UNSPEC]    = { .type = NLA_UNSPEC },
+        [TIPC_NLA_NAME_TABLE_PUBL]      = { .type = NLA_NESTED }
+};
+
 /**
  * struct name_info - name sequence publication info
  * @node_list: circular list of publications made by own node
@@ -995,3 +1001,185 @@ void tipc_nametbl_stop(void)
         table.types = NULL;
         write_unlock_bh(&tipc_nametbl_lock);
 }
+
+int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, struct name_seq *seq,
+                                 struct sub_seq *sseq, u32 *last_publ)
+{
+        void *hdr;
+        struct nlattr *attrs;
+        struct nlattr *publ;
+        struct publication *p;
+
+        if (*last_publ) {
+                list_for_each_entry(p, &sseq->info->zone_list, zone_list)
+                        if (p->key == *last_publ)
+                                break;
+                if (p->key != *last_publ)
+                        return -EPIPE;
+        } else {
+                p = list_first_entry(&sseq->info->zone_list, struct publication,
+                                     zone_list);
+        }
+
+        list_for_each_entry_from(p, &sseq->info->zone_list, zone_list) {
+                *last_publ = p->key;
+
+                hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
+                                  &tipc_genl_v2_family, NLM_F_MULTI,
+                                  TIPC_NL_NAME_TABLE_GET);
+                if (!hdr)
+                        return -EMSGSIZE;
+
+                attrs = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE);
+                if (!attrs)
+                        goto msg_full;
+
+                publ = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
+                if (!publ)
+                        goto attr_msg_full;
+
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, seq->type))
+                        goto publ_msg_full;
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sseq->lower))
+                        goto publ_msg_full;
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sseq->upper))
+                        goto publ_msg_full;
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
+                        goto publ_msg_full;
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
+                        goto publ_msg_full;
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->ref))
+                        goto publ_msg_full;
+                if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
+                        goto publ_msg_full;
+
+                nla_nest_end(msg->skb, publ);
+                nla_nest_end(msg->skb, attrs);
+                genlmsg_end(msg->skb, hdr);
+        }
+        *last_publ = 0;
+
+        return 0;
+
+publ_msg_full:
+        nla_nest_cancel(msg->skb, publ);
+attr_msg_full:
+        nla_nest_cancel(msg->skb, attrs);
+msg_full:
+        genlmsg_cancel(msg->skb, hdr);
+
+        return -EMSGSIZE;
+}
+
+int __tipc_nl_subseq_list(struct tipc_nl_msg *msg, struct name_seq *seq,
+                          u32 *last_lower, u32 *last_publ)
+{
+        struct sub_seq *sseq;
+        struct sub_seq *sseq_start;
+        int err;
+
+        if (*last_lower) {
+                sseq_start = nameseq_find_subseq(seq, *last_lower);
+                if (!sseq_start)
+                        return -EPIPE;
+        } else {
+                sseq_start = seq->sseqs;
+        }
+
+        for (sseq = sseq_start; sseq != &seq->sseqs[seq->first_free]; sseq++) {
+                err = __tipc_nl_add_nametable_publ(msg, seq, sseq, last_publ);
+                if (err) {
+                        *last_lower = sseq->lower;
+                        return err;
+                }
+        }
+        *last_lower = 0;
+
+        return 0;
+}
+
+int __tipc_nl_seq_list(struct tipc_nl_msg *msg, u32 *last_type, u32 *last_lower,
+                       u32 *last_publ)
+{
+        struct hlist_head *seq_head;
+        struct name_seq *seq;
+        int err;
+        int i;
+
+        if (*last_type)
+                i = hash(*last_type);
+        else
+                i = 0;
+
+        for (; i < TIPC_NAMETBL_SIZE; i++) {
+                seq_head = &table.types[i];
+
+                if (*last_type) {
+                        seq = nametbl_find_seq(*last_type);
+                        if (!seq)
+                                return -EPIPE;
+                } else {
+                        seq = hlist_entry_safe((seq_head)->first,
+                                               struct name_seq, ns_list);
+                        if (!seq)
+                                continue;
+                }
+
+                hlist_for_each_entry_from(seq, ns_list) {
+                        spin_lock_bh(&seq->lock);
+
+                        err = __tipc_nl_subseq_list(msg, seq, last_lower,
+                                                    last_publ);
+
+                        if (err) {
+                                *last_type = seq->type;
+                                spin_unlock_bh(&seq->lock);
+                                return err;
+                        }
+                        spin_unlock_bh(&seq->lock);
+                }
+                *last_type = 0;
+        }
+        return 0;
+}
+
+int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+        int err;
+        int done = cb->args[3];
+        u32 last_type = cb->args[0];
+        u32 last_lower = cb->args[1];
+        u32 last_publ = cb->args[2];
+        struct tipc_nl_msg msg;
+
+        if (done)
+                return 0;
+
+        msg.skb = skb;
+        msg.portid = NETLINK_CB(cb->skb).portid;
+        msg.seq = cb->nlh->nlmsg_seq;
+
+        read_lock_bh(&tipc_nametbl_lock);
+
+        err = __tipc_nl_seq_list(&msg, &last_type, &last_lower, &last_publ);
+        if (!err) {
+                done = 1;
+        } else if (err != -EMSGSIZE) {
+                /* We never set seq or call nl_dump_check_consistent() this
+                 * means that setting prev_seq here will cause the consistence
+                 * check to fail in the netlink callback handler. Resulting in
+                 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
+                 * we got an error.
+                 */
+                cb->prev_seq = 1;
+        }
+
+        read_unlock_bh(&tipc_nametbl_lock);
+
+        cb->args[0] = last_type;
+        cb->args[1] = last_lower;
+        cb->args[2] = last_publ;
+        cb->args[3] = done;
+
+        return skb->len;
+}
diff --git a/net/tipc/name_table.h b/net/tipc/name_table.h
index f02f48b9a216..b38ebecac766 100644
--- a/net/tipc/name_table.h
+++ b/net/tipc/name_table.h
@@ -1,7 +1,7 @@
 /*
  * net/tipc/name_table.h: Include file for TIPC name table code
  *
- * Copyright (c) 2000-2006, Ericsson AB
+ * Copyright (c) 2000-2006, 2014, Ericsson AB
  * Copyright (c) 2004-2005, 2010-2011, Wind River Systems
  * All rights reserved.
  *
@@ -84,6 +84,8 @@ struct publication {
 
 extern rwlock_t tipc_nametbl_lock;
 
+int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb);
+
 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space);
 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *node);
 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c
index cb37d30378a8..b891e3905bc4 100644
--- a/net/tipc/netlink.c
+++ b/net/tipc/netlink.c
@@ -37,6 +37,7 @@
 #include "core.h"
 #include "config.h"
 #include "socket.h"
+#include "name_table.h"
 #include "bearer.h"
 #include "link.h"
 #include "node.h"
@@ -81,7 +82,8 @@ static const struct nla_policy tipc_nl_policy[TIPC_NLA_MAX + 1] = {
         [TIPC_NLA_LINK]         = { .type = NLA_NESTED, },
         [TIPC_NLA_MEDIA]        = { .type = NLA_NESTED, },
         [TIPC_NLA_NODE]         = { .type = NLA_NESTED, },
-        [TIPC_NLA_NET]          = { .type = NLA_NESTED, }
+        [TIPC_NLA_NET]          = { .type = NLA_NESTED, },
+        [TIPC_NLA_NAME_TABLE]   = { .type = NLA_NESTED, }
 };
 
 /* Legacy ASCII API */
@@ -185,6 +187,11 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
                 .cmd    = TIPC_NL_NET_SET,
                 .doit   = tipc_nl_net_set,
                 .policy = tipc_nl_policy,
+        },
+        {
+                .cmd    = TIPC_NL_NAME_TABLE_GET,
+                .dumpit = tipc_nl_name_table_dump,
+                .policy = tipc_nl_policy,
         }
 };