gluon-mesh-vpn-fastd: use CAKE for bandwidth shaping

Use CAKE for shaping ingress as well as egress bandwidth shaping.

CAKE allows to better shape egress as well as ingress bandwidth. It not
only performs bandwidth shaping but also flow-queueing.

This in conjunction with the batadv flow dissector allows us to utilize
CAKE for all mesh-implementations currently supported in Gluon.

Signed-off-by: David Bauer <mail@david-bauer.net>

package/gluon-core/luasrc/usr/lib/lua/gluon/util.lua

@@ -296,4 +296,14 @@ function M.subprocess.popen(path, argt, options)
 
 	return pid, parentfds
 end
+
+function M.get_mem_total()
+	for line in io.lines('/proc/meminfo') do
+		local match = line:match('^MemTotal:%s+(%d+)')
+		if match then
+			return tonumber(match)
+		end
+	end
+end
+
 return M

package/gluon-mesh-vpn-fastd/luasrc/usr/lib/lua/gluon/mesh-vpn/provider/fastd.lua

@@ -4,6 +4,8 @@ local site = require 'gluon.site'
 local util = require 'gluon.util'
 local vpn_core = require 'gluon.mesh-vpn'
 
+local unistd = require 'posix.unistd'
+
 local M = {}
 
 function M.public_key()
@@ -25,18 +27,46 @@ function M.active()
 	return site.mesh_vpn.fastd() ~= nil
 end
 
+local function set_limit_simple_tc(ingress_limit, egress_limit)
+	uci:section('simple-tc', 'interface', 'mesh_vpn', {
+		ifname = vpn_core.get_interface(),
+		enabled = true,
+		limit_egress = egress_limit,
+		limit_ingress = ingress_limit,
+	})
+end
+
+local function set_limit_sqm(ingress_limit, egress_limit)
+	uci:section('sqm', 'queue', 'mesh_vpn', {
+		interface = vpn_core.get_interface(),
+		enabled = true,
+		upload = egress_limit,
+		download = ingress_limit,
+		qdisc = 'cake',
+		script = 'piece_of_cake.qos',
+		debug_logging = '0',
+		verbosity = '5',
+	})
+end
+
+local function sqm_available()
+	return unistd.access('/lib/gluon/mesh-vpn/sqm')
+end
+
 function M.set_limit(ingress_limit, egress_limit)
 	uci:delete('simple-tc', 'mesh_vpn')
+	uci:delete('sqm', 'mesh_vpn')
+
 	if ingress_limit ~= nil and egress_limit ~= nil then
-		uci:section('simple-tc', 'interface', 'mesh_vpn', {
-			ifname = vpn_core.get_interface(),
-			enabled = true,
-			limit_egress = egress_limit,
-			limit_ingress = ingress_limit,
-		})
+		if sqm_available() and util.get_mem_total() > 200*1024 then
+			set_limit_sqm(ingress_limit, egress_limit)
+		else
+			set_limit_simple_tc(ingress_limit, egress_limit)
+		end
 	end
 
 	uci:save('simple-tc')
+	uci:save('sqm')
 end
 
 function M.mtu()

package/gluon-status-page/luasrc/lib/gluon/upgrade/500-status-page

 #!/usr/bin/lua
 
 local uci = require('simple-uci').cursor()
+local util = require 'gluon.util'
 
 
-local function get_mem_total()
-	for line in io.lines('/proc/meminfo') do
-		local match = line:match('^MemTotal:%s+(%d+)')
-		if match then
-			return tonumber(match)
-		end
-	end
-end
-
 local max_requests = 32
-if get_mem_total() < 48*1024 then
+if util.get_mem_total() < 48*1024 then
 	max_requests = 16
 end