Re: [PATCH v2 05/11] IB/ipoib: Return IPoIB devices as possible matches to get_net_device_by_port_pkey_ip

["ira.weiny" <ira.weiny@intel.com>]

On Mon, Apr 20, 2015 at 12:03:36PM +0300, Haggai Eran wrote:
> From: Guy Shapiro <guysh@mellanox.com>
> 
> Implement callback that returns network device to ib_core according to
> connection parameters. Check the ipoib device and iterate over all child
> devices to look for a match.
> 
> For each ipoib device we iterate through all upper devices when searching for
> a matching IP, in order to support bonding.
> 
> Signed-off-by: Guy Shapiro <guysh@mellanox.com>
> Signed-off-by: Haggai Eran <haggaie@mellanox.com>
> Signed-off-by: Yotam Kenneth <yotamke@mellanox.com>
> Signed-off-by: Shachar Raindel <raindel@mellanox.com>
> ---
>  drivers/infiniband/ulp/ipoib/ipoib_main.c | 122 +++++++++++++++++++++++++++++-
>  1 file changed, 121 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
> index 7cad4dd87469..89a59a0e17e6 100644
> --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
> +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
> @@ -48,6 +48,9 @@
>  
>  #include <linux/jhash.h>
>  #include <net/arp.h>
> +#include <net/addrconf.h>
> +#include <linux/inetdevice.h>
> +#include <rdma/ib_cache.h>
>  
>  #define DRV_VERSION "1.0.0"
>  
> @@ -91,11 +94,15 @@ struct ib_sa_client ipoib_sa_client;
>  static void ipoib_add_one(struct ib_device *device);
>  static void ipoib_remove_one(struct ib_device *device);
>  static void ipoib_neigh_reclaim(struct rcu_head *rp);
> +static struct net_device *ipoib_get_net_device_by_port_pkey_ip(
> +		struct ib_device *dev, u8 port, u16 pkey,
> +		struct sockaddr *addr);
>  
>  static struct ib_client ipoib_client = {
>  	.name   = "ipoib",
>  	.add    = ipoib_add_one,
> -	.remove = ipoib_remove_one
> +	.remove = ipoib_remove_one,
> +	.get_net_device_by_port_pkey_ip = ipoib_get_net_device_by_port_pkey_ip,
>  };
>  
>  int ipoib_open(struct net_device *dev)
> @@ -222,6 +229,119 @@ static int ipoib_change_mtu(struct net_device *dev, int new_mtu)
>  	return 0;
>  }
>  
> +static bool ipoib_is_dev_match_addr(struct sockaddr *addr,
> +				    struct net_device *dev)
> +{
> +	struct net *net = dev_net(dev);
> +
> +	if (addr->sa_family == AF_INET) {
> +		struct in_device *in_dev = in_dev_get(dev);
> +		struct sockaddr_in *addr_in = (struct sockaddr_in *)addr;
> +		__be32 ret_addr;
> +
> +		if (!in_dev)
> +			return false;
> +
> +		ret_addr = inet_confirm_addr(net, in_dev, 0,
> +					     addr_in->sin_addr.s_addr,
> +					     RT_SCOPE_HOST);
> +		in_dev_put(in_dev);
> +		if (ret_addr)
> +			return true;
> +	}
> +#if IS_ENABLED(CONFIG_IPV6)
> +	else if (addr->sa_family == AF_INET6) {
> +		struct sockaddr_in6 *addr_in6 = (struct sockaddr_in6 *)addr;
> +
> +		if (ipv6_chk_addr(net, &addr_in6->sin6_addr, dev, 1))
> +			return true;
> +	}
> +#endif
> +	return false;
> +}
> +
> +/**
> + * Find a net_device matching the given address, which is an upper device of
> + * the given net_device.
> + * @addr: IP address to look for.
> + * @dev: base IPoIB net_device
> + *
> + * If found, returns the net_device with a reference held. Otherwise return
> + * NULL.
> + */
> +static struct net_device *ipoib_get_net_dev_match_addr(struct sockaddr *addr,
> +						       struct net_device *dev)
> +{
> +	struct net_device *upper,
> +			  *result = NULL;
> +	struct list_head *iter;
> +
> +	if (ipoib_is_dev_match_addr(addr, dev)) {
> +		dev_hold(dev);
> +		return dev;
> +	}
> +
> +	rcu_read_lock();
> +	netdev_for_each_all_upper_dev_rcu(dev, upper, iter) {
> +		if (ipoib_is_dev_match_addr(addr, upper)) {
> +			dev_hold(upper);
> +			result = upper;
> +			break;
> +		}
> +	}
> +	rcu_read_unlock();
> +	return result;
> +}
> +
> +static struct net_device *ipoib_get_net_device_by_port_pkey_ip(
> +		struct ib_device *dev, u8 port, u16 pkey, struct sockaddr *addr)
> +{
> +	struct ipoib_dev_priv *priv;
> +	struct list_head *dev_list;
> +	u16 pkey_index;
> +
> +	ib_find_cached_pkey(dev, port, pkey, &pkey_index);
> +	if (pkey_index == (u16)-1)
> +		return NULL;

Why not check the return value of ib_find_cached_pkey?

> +
> +	if (rdma_node_get_transport(dev->node_type) != RDMA_TRANSPORT_IB)
> +		return NULL;

The use of Link Layer and Transport in this series will need to be reevaluated
based on Michaels work:

https://www.mail-archive.com/linux-rdma@vger.kernel.org/msg24140.html

Ira