Hi, Jiri
On 2017/9/25 1:22, Jiri Pirko wrote:
> From: Yotam Gigi <yot...@mellanox.com>
>
> Make the ipmr module register as a FIB notifier. To do that, implement both
> the ipmr_seq_read and ipmr_dump ops.
>
> The ipmr_seq_read op returns a sequence counter that is incremented on
> every notification related operation done by the ipmr. To implement that,
> add a sequence counter in the netns_ipv4 struct and increment it whenever a
> new MFC route or VIF are added or deleted. The sequence operations are
> protected by the RTNL lock.
>
> The ipmr_dump iterates the list of MFC routes and the list of VIF entries
> and sends notifications about them. The entries dump is done under RCU
> where the VIF dump uses the mrt_lock too, as the vif->dev field can change
> under RCU.
>
> Signed-off-by: Yotam Gigi <yot...@mellanox.com>
> Reviewed-by: Ido Schimmel <ido...@mellanox.com>
> Signed-off-by: Jiri Pirko <j...@mellanox.com>
> ---
> v1->v2:
> - Take the mrt_lock when dumping VIF entries.
> ---
> include/linux/mroute.h | 15 ++++++
> include/net/netns/ipv4.h | 3 ++
> net/ipv4/ipmr.c | 137
> ++++++++++++++++++++++++++++++++++++++++++++++-
> 3 files changed, 153 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/mroute.h b/include/linux/mroute.h
> index 10028f2..54c5cb8 100644
> --- a/include/linux/mroute.h
> +++ b/include/linux/mroute.h
> @@ -5,6 +5,7 @@
> #include <linux/pim.h>
> #include <linux/rhashtable.h>
> #include <net/sock.h>
> +#include <net/fib_notifier.h>
> #include <uapi/linux/mroute.h>
>
> #ifdef CONFIG_IP_MROUTE
> @@ -58,6 +59,14 @@ struct vif_device {
> int link; /* Physical interface index
> */
> };
>
> +struct vif_entry_notifier_info {
> + struct fib_notifier_info info;
> + struct net_device *dev;
> + vifi_t vif_index;
> + unsigned short vif_flags;
> + u32 tb_id;
> +};
> +
> #define VIFF_STATIC 0x8000
>
> #define VIF_EXISTS(_mrt, _idx) ((_mrt)->vif_table[_idx].dev != NULL)
> @@ -146,6 +155,12 @@ struct mfc_cache {
> struct rcu_head rcu;
> };
>
> +struct mfc_entry_notifier_info {
> + struct fib_notifier_info info;
> + struct mfc_cache *mfc;
> + u32 tb_id;
> +};
> +
> struct rtmsg;
> int ipmr_get_route(struct net *net, struct sk_buff *skb,
> __be32 saddr, __be32 daddr,
> diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
> index 8387f09..abc84d9 100644
> --- a/include/net/netns/ipv4.h
> +++ b/include/net/netns/ipv4.h
> @@ -163,6 +163,9 @@ struct netns_ipv4 {
> struct fib_notifier_ops *notifier_ops;
> unsigned int fib_seq; /* protected by rtnl_mutex */
>
> + struct fib_notifier_ops *ipmr_notifier_ops;
Can we add a const here?
> + unsigned int ipmr_seq; /* protected by rtnl_mutex */
> +
> atomic_t rt_genid;
> };
> #endif
> diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
> index 86dc5f9..49879c3 100644
> --- a/net/ipv4/ipmr.c
> +++ b/net/ipv4/ipmr.c
> @@ -264,6 +264,16 @@ static void __net_exit ipmr_rules_exit(struct net *net)
> fib_rules_unregister(net->ipv4.mr_rules_ops);
> rtnl_unlock();
> }
> +
> +static int ipmr_rules_dump(struct net *net, struct notifier_block *nb)
> +{
> + return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR);
> +}
> +
> +static unsigned int ipmr_rules_seq_read(struct net *net)
> +{
> + return fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
> +}
> #else
> #define ipmr_for_each_table(mrt, net) \
> for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
> @@ -298,6 +308,16 @@ static void __net_exit ipmr_rules_exit(struct net *net)
> net->ipv4.mrt = NULL;
> rtnl_unlock();
> }
> +
> +static int ipmr_rules_dump(struct net *net, struct notifier_block *nb)
> +{
> + return 0;
> +}
> +
> +static unsigned int ipmr_rules_seq_read(struct net *net)
> +{
> + return 0;
> +}
> #endif
>
> static inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg,
> @@ -587,6 +607,43 @@ static struct net_device *ipmr_reg_vif(struct net *net,
> struct mr_table *mrt)
> }
> #endif
>
> +static int call_ipmr_vif_entry_notifier(struct notifier_block *nb,
> + struct net *net,
> + enum fib_event_type event_type,
> + struct vif_device *vif,
> + vifi_t vif_index, u32 tb_id)
> +{
> + struct vif_entry_notifier_info info = {
> + .info = {
> + .family = RTNL_FAMILY_IPMR,
> + .net = net,
> + },
> + .dev = vif->dev,
> + .vif_index = vif_index,
> + .vif_flags = vif->flags,
> + .tb_id = tb_id,
> + };
We only use info.info which is fib_notifier_info, the
vif_entry_notifier_info seems to be not needed, why not just
use fib_notifier_info?
> +
> + return call_fib_notifier(nb, net, event_type, &info.info);
> +}
> +
> +static int call_ipmr_mfc_entry_notifier(struct notifier_block *nb,
> + struct net *net,
> + enum fib_event_type event_type,
> + struct mfc_cache *mfc, u32 tb_id)
> +{
> + struct mfc_entry_notifier_info info = {
> + .info = {
> + .family = RTNL_FAMILY_IPMR,
> + .net = net,
> + },
> + .mfc = mfc,
> + .tb_id = tb_id
> + };
> +
As above.
> + return call_fib_notifier(nb, net, event_type, &info.info);
> +}
> +
> /**
> * vif_delete - Delete a VIF entry
> * @notify: Set to 1, if the caller is a notifier_call
> @@ -3050,14 +3107,87 @@ static const struct net_protocol pim_protocol = {
> };
> #endif
>
> +static unsigned int ipmr_seq_read(struct net *net)
> +{
> + ASSERT_RTNL();
> +
> + return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
> +}
> +
> +static int ipmr_dump(struct net *net, struct notifier_block *nb)
> +{
> + struct mr_table *mrt;
> + int err;
> +
> + err = ipmr_rules_dump(net, nb);
> + if (err)
> + return err;
> +
> + ipmr_for_each_table(mrt, net) {
> + struct vif_device *v = &mrt->vif_table[0];
> + struct mfc_cache *mfc;
> + int vifi;
> +
> + /* Notifiy on table VIF entries */
> + read_lock(&mrt_lock);
> + for (vifi = 0; vifi < mrt->maxvif; vifi++, v++) {
> + if (!v->dev)
> + continue;
> +
> + call_ipmr_vif_entry_notifier(nb, net, FIB_EVENT_VIF_ADD,
> + v, vifi, mrt->id);
> + }
> + read_unlock(&mrt_lock);
> +
> + /* Notify on table MFC entries */
> + list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
> + call_ipmr_mfc_entry_notifier(nb, net,
> + FIB_EVENT_ENTRY_ADD, mfc,
> + mrt->id);
> + }
> +
> + return 0;
> +}
> +
> +static const struct fib_notifier_ops ipmr_notifier_ops_template = {
> + .family = RTNL_FAMILY_IPMR,
> + .fib_seq_read = ipmr_seq_read,
> + .fib_dump = ipmr_dump,
> + .owner = THIS_MODULE,
> +};
> +
> +int __net_init ipmr_notifier_init(struct net *net)
> +{
> + struct fib_notifier_ops *ops;
> +
> + net->ipv4.ipmr_seq = 0;
> +
> + ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
> + if (IS_ERR(ops))
> + return PTR_ERR(ops);
> + net->ipv4.ipmr_notifier_ops = ops;
> +
> + return 0;
> +}
> +
> +static void __net_exit ipmr_notifier_exit(struct net *net)
> +{
> + fib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
> + net->ipv4.ipmr_notifier_ops = NULL;
> +}
> +
> /* Setup for IP multicast routing */
> static int __net_init ipmr_net_init(struct net *net)
> {
> int err;
>
> + err = ipmr_notifier_init(net);
> + if (err)
> + goto ipmr_notifier_fail;
> +
> err = ipmr_rules_init(net);
> if (err < 0)
> - goto fail;
> + goto ipmr_rules_fail;
>
> #ifdef CONFIG_PROC_FS
> err = -ENOMEM;
> @@ -3074,7 +3204,9 @@ static int __net_init ipmr_net_init(struct net *net)
> proc_vif_fail:
> ipmr_rules_exit(net);
> #endif
> -fail:
> +ipmr_rules_fail:
> + ipmr_notifier_exit(net);
> +ipmr_notifier_fail:
> return err;
> }
>
> @@ -3084,6 +3216,7 @@ static void __net_exit ipmr_net_exit(struct net *net)
> remove_proc_entry("ip_mr_cache", net->proc_net);
> remove_proc_entry("ip_mr_vif", net->proc_net);
> #endif
> + ipmr_notifier_exit(net);
> ipmr_rules_exit(net);
> }
>
>
