Re: [PATCH v4 4/7] ipv6 addrconf: add new sysctl 'router_solicitation_max_interval'

From: Maciej Żenczykowski <redacted>

Accessible via:
  /proc/sys/net/ipv6/conf/*/router_solicitation_max_interval

For now we default it to the same value as the normal interval.

Signed-off-by: Maciej Żenczykowski <redacted>
---
 include/linux/ipv6.h      |  1 +
 include/net/addrconf.h    |  1 +
 include/uapi/linux/ipv6.h |  1 +
 net/ipv6/addrconf.c       | 11 +++++++++++
 4 files changed, 14 insertions(+)

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index c6dbcd84a2c7..7e9a789be5e0 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h

@@ -18,6 +18,7 @@ struct ipv6_devconf {
        __s32           dad_transmits;
        __s32           rtr_solicits;
        __s32           rtr_solicit_interval;
+       __s32           rtr_solicit_max_interval;
        __s32           rtr_solicit_delay;
        __s32           force_mld_version;
        __s32           mldv1_unsolicited_report_interval;

diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 9826d3a9464c..275e5af4c2f4 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h

@@ -3,6 +3,7 @@

 #define MAX_RTR_SOLICITATIONS          3
 #define RTR_SOLICITATION_INTERVAL      (4*HZ)
+#define RTR_SOLICITATION_MAX_INTERVAL  (4*HZ)

 #define MIN_VALID_LIFETIME             (2*3600)        /* 2 hours */

diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
index 395876060f50..8c2772340c3f 100644
--- a/include/uapi/linux/ipv6.h
+++ b/include/uapi/linux/ipv6.h

@@ -177,6 +177,7 @@ enum {
        DEVCONF_DROP_UNICAST_IN_L2_MULTICAST,
        DEVCONF_DROP_UNSOLICITED_NA,
        DEVCONF_KEEP_ADDR_ON_DOWN,
+       DEVCONF_RTR_SOLICIT_MAX_INTERVAL,
        DEVCONF_MAX
 };

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 6c63bf06fbcf..255be34cdbce 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c

@@ -187,6 +187,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
        .dad_transmits          = 1,
        .rtr_solicits           = MAX_RTR_SOLICITATIONS,
        .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
+       .rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
        .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
        .use_tempaddr           = 0,
        .temp_valid_lft         = TEMP_VALID_LIFETIME,

@@ -232,6 +233,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
        .dad_transmits          = 1,
        .rtr_solicits           = MAX_RTR_SOLICITATIONS,
        .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
+       .rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
        .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
        .use_tempaddr           = 0,
        .temp_valid_lft         = TEMP_VALID_LIFETIME,

@@ -4891,6 +4893,8 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
        array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
        array[DEVCONF_RTR_SOLICIT_INTERVAL] =
                jiffies_to_msecs(cnf->rtr_solicit_interval);
+       array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
+               jiffies_to_msecs(cnf->rtr_solicit_max_interval);
        array[DEVCONF_RTR_SOLICIT_DELAY] =
                jiffies_to_msecs(cnf->rtr_solicit_delay);
        array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;

@@ -5771,6 +5775,13 @@ static const struct ctl_table addrconf_sysctl[] = {
                .proc_handler   = proc_dointvec_jiffies,
        },
        {
+               .procname       = "router_solicitation_max_interval",
+               .data           = &ipv6_devconf.rtr_solicit_max_interval,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec_jiffies,
+       },
+       {
                .procname       = "router_solicitation_delay",
                .data           = &ipv6_devconf.rtr_solicit_delay,
                .maxlen         = sizeof(int),
--

2.8.0.rc3.226.g39d4020