networkd: add support for bond transmit hash policy

This patch adds support  the transmit hash policy to use
for slave selection in balance-xor, 802.3ad, and tlb modes

layer2, layer3+4, layer2+3, encap3+4, encap3+4

Added:
1. BondXmitHashPolicy
2. conf param TransmitHashPolicy

Test conf:
[NetDev]
Name=bond1
Kind=bond

[Bond]
Mode=802.3ad
TransmitHashPolicy=layer2+3

test output:
cat /proc/net/bonding/bond1
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: IEEE 802.3ad Dynamic link aggregation
Transmit Hash Policy: layer2+3 (2)
MII Status: up
MII Polling Interval (ms): 0
Up Delay (ms): 0
Down Delay (ms): 0

802.3ad info
LACP rate: slow
Min links: 0
Aggregator selection policy (ad_select): stable
bond bond1 has no active aggregator

[tomegun: dropped bond_ prefix from new Bond variable, drop repeated man-page section]

1 files changed, 15 insertions, 0 deletions

diff --git a/src/network/networkd-netdev-bond.h b/src/network/networkd-netdev-bond.h
index 09731b73e2..0e9955ee3d 100644
--- a/src/network/networkd-netdev-bond.h
+++ b/src/network/networkd-netdev-bond.h
@@ -37,10 +37,21 @@ typedef enum BondMode {
         _NETDEV_BOND_MODE_INVALID = -1
 } BondMode;
 
+typedef enum BondXmitHashPolicy {
+        NETDEV_BOND_XMIT_HASH_POLICY_LAYER2,
+        NETDEV_BOND_XMIT_HASH_POLICY_LAYER34,
+        NETDEV_BOND_XMIT_HASH_POLICY_LAYER23,
+        NETDEV_BOND_XMIT_HASH_POLICY_ENCAP23,
+        NETDEV_BOND_XMIT_HASH_POLICY_ENCAP34,
+        _NETDEV_BOND_XMIT_HASH_POLICY_MAX,
+        _NETDEV_BOND_XMIT_HASH_POLICY_INVALID = -1
+} BondXmitHashPolicy;
+
 struct Bond {
         NetDev meta;
 
         BondMode mode;
+        BondXmitHashPolicy xmit_hash_policy;
 };
 
 extern const NetDevVTable bond_vtable;
@@ -48,4 +59,8 @@ extern const NetDevVTable bond_vtable;
 const char *bond_mode_to_string(BondMode d) _const_;
 BondMode bond_mode_from_string(const char *d) _pure_;
 
+const char *bond_xmit_hash_policy_to_string(BondXmitHashPolicy d) _const_;
+BondXmitHashPolicy bond_xmit_hash_policy_from_string(const char *d) _pure_;
+
 int config_parse_bond_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);
+int config_parse_bond_xmit_hash_policy(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);