openvswitch: allow specifying ifindex of new interfaces

CRIU is preserving ifindexes of net devices after restoration. However,
current Open vSwitch API does not allow to target ifindex, so we cannot
correctly restore OVS configuration.

Add new OVS_DP_ATTR_IFINDEX for OVS_DP_CMD_NEW and use it as desired
ifindex.
Use OVS_VPORT_ATTR_IFINDEX during OVS_VPORT_CMD_NEW to specify new netdev
ifindex.

Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko@virtuozzo.com>
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index ce3e1738d4278d14820bd1e18083c7bf5d30169d..94066f87e9ee6d58f515751a1d87cfda544b501d 100644 (file)
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -76,6 +76,8 @@ enum ovs_datapath_cmd {
  * datapath.  Always present in notifications.
  * @OVS_DP_ATTR_MEGAFLOW_STATS: Statistics about mega flow masks usage for the
  * datapath. Always present in notifications.
+ * @OVS_DP_ATTR_IFINDEX: Interface index for a new datapath netdev. Only
+ * valid for %OVS_DP_CMD_NEW requests.
  *
  * These attributes follow the &struct ovs_header within the Generic Netlink
  * payload for %OVS_DP_* commands.
@@ -92,6 +94,7 @@ enum ovs_datapath_attr {
        OVS_DP_ATTR_PER_CPU_PIDS,   /* Netlink PIDS to receive upcalls in
                                     * per-cpu dispatch mode
                                     */
+       OVS_DP_ATTR_IFINDEX,
        __OVS_DP_ATTR_MAX
 };
 

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 45f9a7b3410eae2883d36a5e636087237687a956..1ad771d39d1edaa3c5c00b42e8e6b9625b90fc3f 100644 (file)
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -1787,6 +1787,8 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
        parms.dp = dp;
        parms.port_no = OVSP_LOCAL;
        parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
+       parms.desired_ifindex = a[OVS_DP_ATTR_IFINDEX]
+               ? nla_get_u32(a[OVS_DP_ATTR_IFINDEX]) : 0;
 
        /* So far only local changes have been made, now need the lock. */
        ovs_lock();
@@ -2004,6 +2006,7 @@ static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
        [OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
        [OVS_DP_ATTR_MASKS_CACHE_SIZE] =  NLA_POLICY_RANGE(NLA_U32, 0,
                PCPU_MIN_UNIT_SIZE / sizeof(struct mask_cache_entry)),
+       [OVS_DP_ATTR_IFINDEX] = {.type = NLA_U32 },
 };
 
 static const struct genl_small_ops dp_datapath_genl_ops[] = {
@@ -2207,7 +2210,10 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
        if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
            !a[OVS_VPORT_ATTR_UPCALL_PID])
                return -EINVAL;
-       if (a[OVS_VPORT_ATTR_IFINDEX])
+
+       parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
+
+       if (a[OVS_VPORT_ATTR_IFINDEX] && parms.type != OVS_VPORT_TYPE_INTERNAL)
                return -EOPNOTSUPP;
 
        port_no = a[OVS_VPORT_ATTR_PORT_NO]
@@ -2244,11 +2250,12 @@ restart:
        }
 
        parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
-       parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
        parms.options = a[OVS_VPORT_ATTR_OPTIONS];
        parms.dp = dp;
        parms.port_no = port_no;
        parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
+       parms.desired_ifindex = a[OVS_VPORT_ATTR_IFINDEX]
+               ? nla_get_u32(a[OVS_VPORT_ATTR_IFINDEX]) : 0;
 
        vport = new_vport(&parms);
        err = PTR_ERR(vport);

diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c
index 134bc8503461c6e426e6158527f1c8db81388013..35f42c9821c2386a7e1eb0c0b111515d83ae40ef 100644 (file)
--- a/net/openvswitch/vport-internal_dev.c
+++ b/net/openvswitch/vport-internal_dev.c
@@ -147,6 +147,7 @@ static struct vport *internal_dev_create(const struct vport_parms *parms)
        }
 
        dev_net_set(vport->dev, ovs_dp_get_net(vport->dp));
+       dev->ifindex = parms->desired_ifindex;
        internal_dev = internal_dev_priv(vport->dev);
        internal_dev->vport = vport;
 

diff --git a/net/openvswitch/vport.h b/net/openvswitch/vport.h
index 9de5030d9801c7065a4cf5478cfc3778891a6535..7d276f60c0009b8edde5ba35967fc6e1bbf9e81d 100644 (file)
--- a/net/openvswitch/vport.h
+++ b/net/openvswitch/vport.h
@@ -90,12 +90,14 @@ struct vport {
  * @type: New vport's type.
  * @options: %OVS_VPORT_ATTR_OPTIONS attribute from Netlink message, %NULL if
  * none was supplied.
+ * @desired_ifindex: New vport's ifindex.
  * @dp: New vport's datapath.
  * @port_no: New vport's port number.
  */
 struct vport_parms {
        const char *name;
        enum ovs_vport_type type;
+       int desired_ifindex;
        struct nlattr *options;
 
        /* For ovs_vport_alloc(). */