net: bridge: vlan: add rtm range support

Add a new vlandb nl attribute - BRIDGE_VLANDB_ENTRY_RANGE which causes
RTM_NEWVLAN/DELVAN to act on a range. Dumps now automatically compress
similar vlans into ranges. This will be also used when per-vlan options
are introduced and vlans' options match, they will be put into a single
range which is encapsulated in one netlink attribute. We need to run
similar checks as br_process_vlan_info() does because these ranges will
be used for options setting and they'll be able to skip
br_process_vlan_info().

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 4da04f77d9eea3d8359e93ae14953c1e75a6db31..ac38f0b674b8057e8a7690e614ca8152e3e6c5e7 100644 (file)
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -189,6 +189,7 @@ enum {
 enum {
        BRIDGE_VLANDB_ENTRY_UNSPEC,
        BRIDGE_VLANDB_ENTRY_INFO,
+       BRIDGE_VLANDB_ENTRY_RANGE,
        __BRIDGE_VLANDB_ENTRY_MAX,
 };
 #define BRIDGE_VLANDB_ENTRY_MAX (__BRIDGE_VLANDB_ENTRY_MAX - 1)

diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index 89d5fa75c575f978eb1df38ba326335936e8eb93..9d64a86f2cbdfcd5004c04ae8103cde893765c37 100644 (file)
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -1506,7 +1506,8 @@ void br_vlan_port_event(struct net_bridge_port *p, unsigned long event)
        }
 }
 
-static bool br_vlan_fill_vids(struct sk_buff *skb, u16 vid, u16 flags)
+static bool br_vlan_fill_vids(struct sk_buff *skb, u16 vid, u16 vid_range,
+                             u16 flags)
 {
        struct bridge_vlan_info info;
        struct nlattr *nest;
@@ -1525,6 +1526,11 @@ static bool br_vlan_fill_vids(struct sk_buff *skb, u16 vid, u16 flags)
        if (nla_put(skb, BRIDGE_VLANDB_ENTRY_INFO, sizeof(info), &info))
                goto out_err;
 
+       if (vid_range && vid < vid_range &&
+           !(flags & BRIDGE_VLAN_INFO_PVID) &&
+           nla_put_u16(skb, BRIDGE_VLANDB_ENTRY_RANGE, vid_range))
+               goto out_err;
+
        nla_nest_end(skb, nest);
 
        return true;
@@ -1534,14 +1540,22 @@ out_err:
        return false;
 }
 
+/* check if v_curr can enter a range ending in range_end */
+static bool br_vlan_can_enter_range(const struct net_bridge_vlan *v_curr,
+                                   const struct net_bridge_vlan *range_end)
+{
+       return v_curr->vid - range_end->vid == 1 &&
+              range_end->flags == v_curr->flags;
+}
+
 static int br_vlan_dump_dev(const struct net_device *dev,
                            struct sk_buff *skb,
                            struct netlink_callback *cb)
 {
+       struct net_bridge_vlan *v, *range_start = NULL, *range_end = NULL;
        struct net_bridge_vlan_group *vg;
        int idx = 0, s_idx = cb->args[1];
        struct nlmsghdr *nlh = NULL;
-       struct net_bridge_vlan *v;
        struct net_bridge_port *p;
        struct br_vlan_msg *bvm;
        struct net_bridge *br;
@@ -1576,22 +1590,49 @@ static int br_vlan_dump_dev(const struct net_device *dev,
        bvm->ifindex = dev->ifindex;
        pvid = br_get_pvid(vg);
 
+       /* idx must stay at range's beginning until it is filled in */
        list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
                if (!br_vlan_should_use(v))
                        continue;
-               if (idx < s_idx)
-                       goto skip;
-               if (!br_vlan_fill_vids(skb, v->vid, br_vlan_flags(v, pvid))) {
-                       err = -EMSGSIZE;
-                       break;
+               if (idx < s_idx) {
+                       idx++;
+                       continue;
                }
-skip:
-               idx++;
+
+               if (!range_start) {
+                       range_start = v;
+                       range_end = v;
+                       continue;
+               }
+
+               if (v->vid == pvid || !br_vlan_can_enter_range(v, range_end)) {
+                       u16 flags = br_vlan_flags(range_start, pvid);
+
+                       if (!br_vlan_fill_vids(skb, range_start->vid,
+                                              range_end->vid, flags)) {
+                               err = -EMSGSIZE;
+                               break;
+                       }
+                       /* advance number of filled vlans */
+                       idx += range_end->vid - range_start->vid + 1;
+
+                       range_start = v;
+               }
+               range_end = v;
        }
-       if (err)
-               cb->args[1] = idx;
-       else
-               cb->args[1] = 0;
+
+       /* err will be 0 and range_start will be set in 3 cases here:
+        * - first vlan (range_start == range_end)
+        * - last vlan (range_start == range_end, not in range)
+        * - last vlan range (range_start != range_end, in range)
+        */
+       if (!err && range_start &&
+           !br_vlan_fill_vids(skb, range_start->vid, range_end->vid,
+                              br_vlan_flags(range_start, pvid)))
+               err = -EMSGSIZE;
+
+       cb->args[1] = err ? idx : 0;
+
        nlmsg_end(skb, nlh);
 
        return err;
@@ -1646,13 +1687,14 @@ out_err:
 static const struct nla_policy br_vlan_db_policy[BRIDGE_VLANDB_ENTRY_MAX + 1] = {
        [BRIDGE_VLANDB_ENTRY_INFO]      = { .type = NLA_EXACT_LEN,
                                            .len = sizeof(struct bridge_vlan_info) },
+       [BRIDGE_VLANDB_ENTRY_RANGE]     = { .type = NLA_U16 },
 };
 
 static int br_vlan_rtm_process_one(struct net_device *dev,
                                   const struct nlattr *attr,
                                   int cmd, struct netlink_ext_ack *extack)
 {
-       struct bridge_vlan_info *vinfo, *vinfo_last = NULL;
+       struct bridge_vlan_info *vinfo, vrange_end, *vinfo_last = NULL;
        struct nlattr *tb[BRIDGE_VLANDB_ENTRY_MAX + 1];
        struct net_bridge_vlan_group *vg;
        struct net_bridge_port *p = NULL;
@@ -1683,6 +1725,7 @@ static int br_vlan_rtm_process_one(struct net_device *dev,
                NL_SET_ERR_MSG_MOD(extack, "Missing vlan entry info");
                return -EINVAL;
        }
+       memset(&vrange_end, 0, sizeof(vrange_end));
 
        vinfo = nla_data(tb[BRIDGE_VLANDB_ENTRY_INFO]);
        if (vinfo->flags & (BRIDGE_VLAN_INFO_RANGE_BEGIN |
@@ -1693,6 +1736,21 @@ static int br_vlan_rtm_process_one(struct net_device *dev,
        if (!br_vlan_valid_id(vinfo->vid, extack))
                return -EINVAL;
 
+       if (tb[BRIDGE_VLANDB_ENTRY_RANGE]) {
+               vrange_end.vid = nla_get_u16(tb[BRIDGE_VLANDB_ENTRY_RANGE]);
+               /* validate user-provided flags without RANGE_BEGIN */
+               vrange_end.flags = BRIDGE_VLAN_INFO_RANGE_END | vinfo->flags;
+               vinfo->flags |= BRIDGE_VLAN_INFO_RANGE_BEGIN;
+
+               /* vinfo_last is the range start, vinfo the range end */
+               vinfo_last = vinfo;
+               vinfo = &vrange_end;
+
+               if (!br_vlan_valid_id(vinfo->vid, extack) ||
+                   !br_vlan_valid_range(vinfo, vinfo_last, extack))
+                       return -EINVAL;
+       }
+
        switch (cmd) {
        case RTM_NEWVLAN:
                cmdmap = RTM_SETLINK;