[NET]: Convert link dumping to new netlink api

Transforms netlink code to dump link tables to use the new
netlink api. Makes rtnl_getlink() available regardless of the
availability of the wireless extensions.

Adding copy_rtnl_link_stats() avoids the structural dependency
of struct rtnl_link_stats on struct net_device_stats and thus
avoids troubles later on.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 137 insertions, 144 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 2adc966d981e..93ba04fb8444 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -218,41 +218,73 @@ static void set_operstate(struct net_device *dev, unsigned char transition)
         }
 }
 
-static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
-                                 int type, u32 pid, u32 seq, u32 change, 
-                                 unsigned int flags)
+static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
+                                 struct net_device_stats *b)
 {
-        struct ifinfomsg *r;
-        struct nlmsghdr  *nlh;
-        unsigned char    *b = skb->tail;
-
-        nlh = NLMSG_NEW(skb, pid, seq, type, sizeof(*r), flags);
-        r = NLMSG_DATA(nlh);
-        r->ifi_family = AF_UNSPEC;
-        r->__ifi_pad = 0;
-        r->ifi_type = dev->type;
-        r->ifi_index = dev->ifindex;
-        r->ifi_flags = dev_get_flags(dev);
-        r->ifi_change = change;
+        a->rx_packets = b->rx_packets;
+        a->tx_packets = b->tx_packets;
+        a->rx_bytes = b->rx_bytes;
+        a->tx_bytes = b->tx_bytes;
+        a->rx_errors = b->rx_errors;
+        a->tx_errors = b->tx_errors;
+        a->rx_dropped = b->rx_dropped;
+        a->tx_dropped = b->tx_dropped;
+
+        a->multicast = b->multicast;
+        a->collisions = b->collisions;
+
+        a->rx_length_errors = b->rx_length_errors;
+        a->rx_over_errors = b->rx_over_errors;
+        a->rx_crc_errors = b->rx_crc_errors;
+        a->rx_frame_errors = b->rx_frame_errors;
+        a->rx_fifo_errors = b->rx_fifo_errors;
+        a->rx_missed_errors = b->rx_missed_errors;
+
+        a->tx_aborted_errors = b->tx_aborted_errors;
+        a->tx_carrier_errors = b->tx_carrier_errors;
+        a->tx_fifo_errors = b->tx_fifo_errors;
+        a->tx_heartbeat_errors = b->tx_heartbeat_errors;
+        a->tx_window_errors = b->tx_window_errors;
+
+        a->rx_compressed = b->rx_compressed;
+        a->tx_compressed = b->tx_compressed;
+};
 
-        RTA_PUT(skb, IFLA_IFNAME, strlen(dev->name)+1, dev->name);
+static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
+                            void *iwbuf, int iwbuflen, int type, u32 pid,
+                            u32 seq, u32 change, unsigned int flags)
+{
+        struct ifinfomsg *ifm;
+        struct nlmsghdr *nlh;
 
-        if (1) {
-                u32 txqlen = dev->tx_queue_len;
-                RTA_PUT(skb, IFLA_TXQLEN, sizeof(txqlen), &txqlen);
-        }
+        nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
+        if (nlh == NULL)
+                return -ENOBUFS;
 
-        if (1) {
-                u32 weight = dev->weight;
-                RTA_PUT(skb, IFLA_WEIGHT, sizeof(weight), &weight);
-        }
+        ifm = nlmsg_data(nlh);
+        ifm->ifi_family = AF_UNSPEC;
+        ifm->__ifi_pad = 0;
+        ifm->ifi_type = dev->type;
+        ifm->ifi_index = dev->ifindex;
+        ifm->ifi_flags = dev_get_flags(dev);
+        ifm->ifi_change = change;
+
+        NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
+        NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
+        NLA_PUT_U32(skb, IFLA_WEIGHT, dev->weight);
+        NLA_PUT_U8(skb, IFLA_OPERSTATE,
+                   netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
+        NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
+        NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
+
+        if (dev->ifindex != dev->iflink)
+                NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
+
+        if (dev->master)
+                NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
 
-        if (1) {
-                u8 operstate = netif_running(dev)?dev->operstate:IF_OPER_DOWN;
-                u8 link_mode = dev->link_mode;
-                RTA_PUT(skb, IFLA_OPERSTATE, sizeof(operstate), &operstate);
-                RTA_PUT(skb, IFLA_LINKMODE, sizeof(link_mode), &link_mode);
-        }
+        if (dev->qdisc_sleeping)
+                NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
 
         if (1) {
                 struct rtnl_link_ifmap map = {
@@ -263,58 +295,38 @@ static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                         .dma         = dev->dma,
                         .port        = dev->if_port,
                 };
-                RTA_PUT(skb, IFLA_MAP, sizeof(map), &map);
+                NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
         }
 
         if (dev->addr_len) {
-                RTA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
-                RTA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
-        }
-
-        if (1) {
-                u32 mtu = dev->mtu;
-                RTA_PUT(skb, IFLA_MTU, sizeof(mtu), &mtu);
-        }
-
-        if (dev->ifindex != dev->iflink) {
-                u32 iflink = dev->iflink;
-                RTA_PUT(skb, IFLA_LINK, sizeof(iflink), &iflink);
-        }
-
-        if (dev->qdisc_sleeping)
-                RTA_PUT(skb, IFLA_QDISC,
-                        strlen(dev->qdisc_sleeping->ops->id) + 1,
-                        dev->qdisc_sleeping->ops->id);
-        
-        if (dev->master) {
-                u32 master = dev->master->ifindex;
-                RTA_PUT(skb, IFLA_MASTER, sizeof(master), &master);
+                NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
+                NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
         }
 
         if (dev->get_stats) {
-                unsigned long *stats = (unsigned long*)dev->get_stats(dev);
+                struct net_device_stats *stats = dev->get_stats(dev);
                 if (stats) {
-                        struct rtattr  *a;
-                        __u32          *s;
-                        int             i;
-                        int             n = sizeof(struct rtnl_link_stats)/4;
-
-                        a = __RTA_PUT(skb, IFLA_STATS, n*4);
-                        s = RTA_DATA(a);
-                        for (i=0; i<n; i++)
-                                s[i] = stats[i];
+                        struct nlattr *attr;
+
+                        attr = nla_reserve(skb, IFLA_STATS,
+                                           sizeof(struct rtnl_link_stats));
+                        if (attr == NULL)
+                                goto nla_put_failure;
+
+                        copy_rtnl_link_stats(nla_data(attr), stats);
                 }
         }
-        nlh->nlmsg_len = skb->tail - b;
-        return skb->len;
 
-nlmsg_failure:
-rtattr_failure:
-        skb_trim(skb, b - skb->data);
-        return -1;
+        if (iwbuf)
+                NLA_PUT(skb, IFLA_WIRELESS, iwbuflen, iwbuf);
+
+        return nlmsg_end(skb, nlh);
+
+nla_put_failure:
+        return nlmsg_cancel(skb, nlh);
 }
 
-static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
+static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
         int idx;
         int s_idx = cb->args[0];
@@ -324,10 +336,9 @@ static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *c
         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
                 if (idx < s_idx)
                         continue;
-                if (rtnetlink_fill_ifinfo(skb, dev, RTM_NEWLINK,
-                                          NETLINK_CB(cb->skb).pid,
-                                          cb->nlh->nlmsg_seq, 0,
-                                          NLM_F_MULTI) <= 0)
+                if (rtnl_fill_ifinfo(skb, dev, NULL, 0, RTM_NEWLINK,
+                                     NETLINK_CB(cb->skb).pid,
+                                     cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
                         break;
         }
         read_unlock(&dev_base_lock);
@@ -515,84 +526,69 @@ errout:
         return err;
 }
 
-#ifdef CONFIG_NET_WIRELESS_RTNETLINK
-static int do_getlink(struct sk_buff *in_skb, struct nlmsghdr* in_nlh, void *arg)
+static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
-        struct ifinfomsg  *ifm = NLMSG_DATA(in_nlh);
-        struct rtattr    **ida = arg;
-        struct net_device *dev;
-        struct ifinfomsg *r;
-        struct nlmsghdr  *nlh;
-        int err = -ENOBUFS;
-        struct sk_buff *skb;
-        unsigned char    *b;
-        char *iw_buf = NULL;
+        struct ifinfomsg *ifm;
+        struct nlattr *tb[IFLA_MAX+1];
+        struct net_device *dev = NULL;
+        struct sk_buff *nskb;
+        char *iw_buf = NULL, *iw = NULL;
         int iw_buf_len = 0;
+        int err, payload;
 
-        if (ifm->ifi_index >= 0)
+        err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
+        if (err < 0)
+                goto errout;
+
+        ifm = nlmsg_data(nlh);
+        if (ifm->ifi_index >= 0) {
                 dev = dev_get_by_index(ifm->ifi_index);
-        else
+                if (dev == NULL)
+                        return -ENODEV;
+        } else
                 return -EINVAL;
-        if (!dev)
-                return -ENODEV;
 
-#ifdef CONFIG_NET_WIRELESS_RTNETLINK
-        if (ida[IFLA_WIRELESS - 1]) {
 
+#ifdef CONFIG_NET_WIRELESS_RTNETLINK
+        if (tb[IFLA_WIRELESS]) {
                 /* Call Wireless Extensions. We need to know the size before
                  * we can alloc. Various stuff checked in there... */
-                err = wireless_rtnetlink_get(dev, RTA_DATA(ida[IFLA_WIRELESS - 1]), ida[IFLA_WIRELESS - 1]->rta_len, &iw_buf, &iw_buf_len);
-                if (err)
-                        goto out;
+                err = wireless_rtnetlink_get(dev, nla_data(tb[IFLA_WIRELESS]),
+                                             nla_len(tb[IFLA_WIRELESS]),
+                                             &iw_buf, &iw_buf_len);
+                if (err < 0)
+                        goto errout;
+
+                iw += IW_EV_POINT_OFF;
         }
 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 
-        /* Create a skb big enough to include all the data.
-         * Some requests are way bigger than 4k... Jean II */
-        skb = alloc_skb((NLMSG_LENGTH(sizeof(*r))) + (RTA_SPACE(iw_buf_len)),
-                        GFP_KERNEL);
-        if (!skb)
-                goto out;
-        b = skb->tail;
-
-        /* Put in the message the usual good stuff */
-        nlh = NLMSG_PUT(skb, NETLINK_CB(in_skb).pid, in_nlh->nlmsg_seq,
-                        RTM_NEWLINK, sizeof(*r));
-        r = NLMSG_DATA(nlh);
-        r->ifi_family = AF_UNSPEC;
-        r->__ifi_pad = 0;
-        r->ifi_type = dev->type;
-        r->ifi_index = dev->ifindex;
-        r->ifi_flags = dev->flags;
-        r->ifi_change = 0;
-
-        /* Put the wireless payload if it exist */
-        if(iw_buf != NULL)
-                RTA_PUT(skb, IFLA_WIRELESS, iw_buf_len,
-                        iw_buf + IW_EV_POINT_OFF);
-
-        nlh->nlmsg_len = skb->tail - b;
-
-        /* Needed ? */
-        NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid;
-
-        err = netlink_unicast(rtnl, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
+        payload = NLMSG_ALIGN(sizeof(struct ifinfomsg) +
+                              nla_total_size(iw_buf_len));
+        nskb = nlmsg_new(nlmsg_total_size(payload), GFP_KERNEL);
+        if (nskb == NULL) {
+                err = -ENOBUFS;
+                goto errout;
+        }
+
+        err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, RTM_NEWLINK,
+                               NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0, 0);
+        if (err <= 0) {
+                kfree_skb(skb);
+                goto errout;
+        }
+
+        err = netlink_unicast(rtnl, skb, NETLINK_CB(skb).pid, MSG_DONTWAIT);
         if (err > 0)
                 err = 0;
-out:
-        if(iw_buf != NULL)
-                kfree(iw_buf);
+errout:
+        kfree(iw_buf);
         dev_put(dev);
-        return err;
 
-rtattr_failure:
-nlmsg_failure:
-        kfree_skb(skb);
-        goto out;
+        return err;
 }
-#endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 
-static int rtnetlink_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
+static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
 {
         int idx;
         int s_idx = cb->family;
@@ -623,11 +619,11 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
                                sizeof(struct rtnl_link_ifmap) +
                                sizeof(struct rtnl_link_stats) + 128);
 
-        skb = alloc_skb(size, GFP_KERNEL);
+        skb = nlmsg_new(size, GFP_KERNEL);
         if (!skb)
                 return;
 
-        if (rtnetlink_fill_ifinfo(skb, dev, type, 0, 0, change, 0) < 0) {
+        if (rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0) < 0) {
                 kfree_skb(skb);
                 return;
         }
@@ -757,14 +753,11 @@ static void rtnetlink_rcv(struct sock *sk, int len)
 
 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
 {
-        [RTM_GETLINK     - RTM_BASE] = {
-#ifdef CONFIG_NET_WIRELESS_RTNETLINK
-                                         .doit   = do_getlink,
-#endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
-                                         .dumpit = rtnetlink_dump_ifinfo },
+        [RTM_GETLINK     - RTM_BASE] = { .doit   = rtnl_getlink,
+                                         .dumpit = rtnl_dump_ifinfo      },
         [RTM_SETLINK     - RTM_BASE] = { .doit   = rtnl_setlink          },
-        [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
-        [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
+        [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
+        [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnl_dump_all         },
         [RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add             },
         [RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete          },
         [RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info       },
@@ -772,7 +765,7 @@ static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
         [RTM_NEWRULE     - RTM_BASE] = { .doit   = fib_nl_newrule        },
         [RTM_DELRULE     - RTM_BASE] = { .doit   = fib_nl_delrule        },
 #endif
-        [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
+        [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
         [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info    },
         [RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set          },
 };