devlink: factor out building a snapshot notification

We'll need to send snapshot info back on the socket
which requested a snapshot to be created. Factor out
constructing a snapshot description from the broadcast
notification code.

v3: new patch

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 80f9772..2b7c60c 100644 (file)
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -3716,24 +3716,26 @@ nla_put_failure:
        return err;
 }
 
-static void devlink_nl_region_notify(struct devlink_region *region,
-                                    struct devlink_snapshot *snapshot,
-                                    enum devlink_command cmd)
+static struct sk_buff *
+devlink_nl_region_notify_build(struct devlink_region *region,
+                              struct devlink_snapshot *snapshot,
+                              enum devlink_command cmd, u32 portid, u32 seq)
 {
        struct devlink *devlink = region->devlink;
        struct sk_buff *msg;
        void *hdr;
        int err;
 
-       WARN_ON(cmd != DEVLINK_CMD_REGION_NEW && cmd != DEVLINK_CMD_REGION_DEL);
 
        msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
        if (!msg)
-               return;
+               return ERR_PTR(-ENOMEM);
 
-       hdr = genlmsg_put(msg, 0, 0, &devlink_nl_family, 0, cmd);
-       if (!hdr)
+       hdr = genlmsg_put(msg, portid, seq, &devlink_nl_family, 0, cmd);
+       if (!hdr) {
+               err = -EMSGSIZE;
                goto out_free_msg;
+       }
 
        err = devlink_nl_put_handle(msg, devlink);
        if (err)
@@ -3757,15 +3759,30 @@ static void devlink_nl_region_notify(struct devlink_region *region,
        }
        genlmsg_end(msg, hdr);
 
-       genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink),
-                               msg, 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
-
-       return;
+       return msg;
 
 out_cancel_msg:
        genlmsg_cancel(msg, hdr);
 out_free_msg:
        nlmsg_free(msg);
+       return ERR_PTR(err);
+}
+
+static void devlink_nl_region_notify(struct devlink_region *region,
+                                    struct devlink_snapshot *snapshot,
+                                    enum devlink_command cmd)
+{
+       struct devlink *devlink = region->devlink;
+       struct sk_buff *msg;
+
+       WARN_ON(cmd != DEVLINK_CMD_REGION_NEW && cmd != DEVLINK_CMD_REGION_DEL);
+
+       msg = devlink_nl_region_notify_build(region, snapshot, cmd, 0, 0);
+       if (IS_ERR(msg))
+               return;
+
+       genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink),
+                               msg, 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
 }
 
 /**