diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 4ace6d60d8..9a8d13d6c5 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -3491,6 +3491,18 @@ Token=prefixstable:2002:da8:1::
+
+ CompensationMode=
+
+ Takes one of none, atm, or ptm.
+ Specifies the compensation mode for overhead calculation. When none, no
+ compensation is taken into account. When atm, enables the compensation for
+ ATM cell framing, which is normally found on ADSL links. When ptm, enables
+ the compensation for PTM encoding, which is normally found on VDSL2 links and uses a 64b/65b
+ encoding scheme. Defaults to unset and the kernel's default is used.
+
+
+
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index c34b3e1812..2d0e1f833f 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -388,6 +388,7 @@ CAKE.Handle, config_parse_qdisc_handle,
CAKE.Bandwidth, config_parse_cake_bandwidth, QDISC_KIND_CAKE, 0
CAKE.AutoRateIngress, config_parse_cake_tristate, QDISC_KIND_CAKE, 0
CAKE.OverheadBytes, config_parse_cake_overhead, QDISC_KIND_CAKE, 0
+CAKE.CompensationMode, config_parse_cake_compensation_mode, QDISC_KIND_CAKE, 0
ControlledDelay.Parent, config_parse_qdisc_parent, QDISC_KIND_CODEL, 0
ControlledDelay.Handle, config_parse_qdisc_handle, QDISC_KIND_CODEL, 0
ControlledDelay.PacketLimit, config_parse_controlled_delay_u32, QDISC_KIND_CODEL, 0
diff --git a/src/network/tc/cake.c b/src/network/tc/cake.c
index 813a679bf7..fe007c00fd 100644
--- a/src/network/tc/cake.c
+++ b/src/network/tc/cake.c
@@ -9,6 +9,7 @@
#include "netlink-util.h"
#include "parse-util.h"
#include "qdisc.h"
+#include "string-table.h"
#include "string-util.h"
static int cake_init(QDisc *qdisc) {
@@ -19,6 +20,7 @@ static int cake_init(QDisc *qdisc) {
c = CAKE(qdisc);
c->autorate = -1;
+ c->compensation_mode = _CAKE_COMPENSATION_MODE_INVALID;
return 0;
}
@@ -55,6 +57,12 @@ static int cake_fill_message(Link *link, QDisc *qdisc, sd_netlink_message *req)
return log_link_error_errno(link, r, "Could not append TCA_CAKE_OVERHEAD attribute: %m");
}
+ if (c->compensation_mode >= 0) {
+ r = sd_netlink_message_append_u32(req, TCA_CAKE_ATM, c->compensation_mode);
+ if (r < 0)
+ return log_link_error_errno(link, r, "Could not append TCA_CAKE_ATM attribute: %m");
+ }
+
r = sd_netlink_message_close_container(req);
if (r < 0)
return log_link_error_errno(link, r, "Could not close container TCA_OPTIONS: %m");
@@ -234,6 +242,67 @@ int config_parse_cake_tristate(
return 0;
}
+static const char * const cake_compensation_mode_table[_CAKE_COMPENSATION_MODE_MAX] = {
+ [CAKE_COMPENSATION_MODE_NONE] = "none",
+ [CAKE_COMPENSATION_MODE_ATM] = "atm",
+ [CAKE_COMPENSATION_MODE_PTM] = "ptm",
+};
+
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING(cake_compensation_mode, CakeCompensationMode);
+
+int config_parse_cake_compensation_mode(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ _cleanup_(qdisc_free_or_set_invalidp) QDisc *qdisc = NULL;
+ CommonApplicationsKeptEnhanced *c;
+ Network *network = data;
+ CakeCompensationMode mode;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ r = qdisc_new_static(QDISC_KIND_CAKE, network, filename, section_line, &qdisc);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "More than one kind of queueing discipline, ignoring assignment: %m");
+ return 0;
+ }
+
+ c = CAKE(qdisc);
+
+ if (isempty(rvalue)) {
+ c->compensation_mode = _CAKE_COMPENSATION_MODE_INVALID;
+ TAKE_PTR(qdisc);
+ return 0;
+ }
+
+ mode = cake_compensation_mode_from_string(rvalue);
+ if (mode < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, mode,
+ "Failed to parse '%s=', ignoring assignment: %s",
+ lvalue, rvalue);
+ return 0;
+ }
+
+ c->compensation_mode = mode;
+ TAKE_PTR(qdisc);
+ return 0;
+}
+
const QDiscVTable cake_vtable = {
.object_size = sizeof(CommonApplicationsKeptEnhanced),
.tca_kind = "cake",
diff --git a/src/network/tc/cake.h b/src/network/tc/cake.h
index 08fa3c266b..549b4e3c80 100644
--- a/src/network/tc/cake.h
+++ b/src/network/tc/cake.h
@@ -2,9 +2,19 @@
* Copyright © 2020 VMware, Inc. */
#pragma once
+#include
+
#include "conf-parser.h"
#include "qdisc.h"
+typedef enum CakeCompensationMode {
+ CAKE_COMPENSATION_MODE_NONE = CAKE_ATM_NONE,
+ CAKE_COMPENSATION_MODE_ATM = CAKE_ATM_ATM,
+ CAKE_COMPENSATION_MODE_PTM = CAKE_ATM_PTM,
+ _CAKE_COMPENSATION_MODE_MAX,
+ _CAKE_COMPENSATION_MODE_INVALID = -EINVAL,
+} CakeCompensationMode;
+
typedef struct CommonApplicationsKeptEnhanced {
QDisc meta;
@@ -15,6 +25,7 @@ typedef struct CommonApplicationsKeptEnhanced {
/* Overhead compensation parameters */
bool overhead_set;
int overhead;
+ CakeCompensationMode compensation_mode;
} CommonApplicationsKeptEnhanced;
@@ -24,3 +35,4 @@ extern const QDiscVTable cake_vtable;
CONFIG_PARSER_PROTOTYPE(config_parse_cake_bandwidth);
CONFIG_PARSER_PROTOTYPE(config_parse_cake_overhead);
CONFIG_PARSER_PROTOTYPE(config_parse_cake_tristate);
+CONFIG_PARSER_PROTOTYPE(config_parse_cake_compensation_mode);
diff --git a/test/fuzz/fuzz-network-parser/directives.network b/test/fuzz/fuzz-network-parser/directives.network
index 83e9fa9054..79ca97c90b 100644
--- a/test/fuzz/fuzz-network-parser/directives.network
+++ b/test/fuzz/fuzz-network-parser/directives.network
@@ -470,6 +470,7 @@ Handle=
Bandwidth=
AutoRateIngress=
OverheadBytes=
+CompensationMode=
[TrafficControlQueueingDiscipline]
Parent=
NetworkEmulatorDelaySec=