IB/addr: Simplify resolving IPv4 addresses

Merge resolve local/remote address resolution into a single
data flow to ensure consistent access and use of the local routing
tables.

Based on work from:
David Wilder <dwilder@us.ibm.com>
Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index de5fe16..38a7184 100644 (file)
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -184,17 +184,6 @@ static void addr_send_arp(struct sockaddr *dst_in)
        memset(&fl, 0, sizeof fl);
 
        switch (dst_in->sa_family) {
-       case AF_INET:
-               fl.nl_u.ip4_u.daddr =
-                       ((struct sockaddr_in *) dst_in)->sin_addr.s_addr;
-
-               if (ip_route_output_key(&init_net, &rt, &fl))
-                       return;
-
-               neigh_event_send(rt->u.dst.neighbour, NULL);
-               ip_rt_put(rt);
-               break;
-
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
        case AF_INET6:
        {
@@ -215,9 +204,9 @@ static void addr_send_arp(struct sockaddr *dst_in)
        }
 }
 
-static int addr4_resolve_remote(struct sockaddr_in *src_in,
-                              struct sockaddr_in *dst_in,
-                              struct rdma_dev_addr *addr)
+static int addr4_resolve(struct sockaddr_in *src_in,
+                        struct sockaddr_in *dst_in,
+                        struct rdma_dev_addr *addr)
 {
        __be32 src_ip = src_in->sin_addr.s_addr;
        __be32 dst_ip = dst_in->sin_addr.s_addr;
@@ -235,6 +224,16 @@ static int addr4_resolve_remote(struct sockaddr_in *src_in,
        if (ret)
                goto out;
 
+       src_in->sin_family = AF_INET;
+       src_in->sin_addr.s_addr = rt->rt_src;
+
+       if (rt->idev->dev->flags & IFF_LOOPBACK) {
+               ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
+               if (!ret)
+                       memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
+               goto put;
+       }
+
        /* If the device does ARP internally, return 'done' */
        if (rt->idev->dev->flags & IFF_NOARP) {
                rdma_copy_addr(addr, rt->idev->dev, NULL);
@@ -242,21 +241,14 @@ static int addr4_resolve_remote(struct sockaddr_in *src_in,
        }
 
        neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->idev->dev);
-       if (!neigh) {
+       if (!neigh || !(neigh->nud_state & NUD_VALID)) {
+               neigh_event_send(rt->u.dst.neighbour, NULL);
                ret = -ENODATA;
+               if (neigh)
+                       goto release;
                goto put;
        }
 
-       if (!(neigh->nud_state & NUD_VALID)) {
-               ret = -ENODATA;
-               goto release;
-       }
-
-       if (!src_ip) {
-               src_in->sin_family = dst_in->sin_family;
-               src_in->sin_addr.s_addr = rt->rt_src;
-       }
-
        ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
 release:
        neigh_release(neigh);
@@ -305,12 +297,12 @@ static int addr6_resolve_remote(struct sockaddr_in6 *src_in,
 }
 #endif
 
-static int addr_resolve_remote(struct sockaddr *src_in,
-                               struct sockaddr *dst_in,
-                               struct rdma_dev_addr *addr)
+static int addr_resolve(struct sockaddr *src_in,
+                       struct sockaddr *dst_in,
+                       struct rdma_dev_addr *addr)
 {
        if (src_in->sa_family == AF_INET) {
-               return addr4_resolve_remote((struct sockaddr_in *) src_in,
+               return addr4_resolve((struct sockaddr_in *) src_in,
                        (struct sockaddr_in *) dst_in, addr);
        } else
                return addr6_resolve_remote((struct sockaddr_in6 *) src_in,
@@ -330,8 +322,7 @@ static void process_req(struct work_struct *work)
                if (req->status == -ENODATA) {
                        src_in = (struct sockaddr *) &req->src_addr;
                        dst_in = (struct sockaddr *) &req->dst_addr;
-                       req->status = addr_resolve_remote(src_in, dst_in,
-                                                         req->addr);
+                       req->status = addr_resolve(src_in, dst_in, req->addr);
                        if (req->status && time_after_eq(jiffies, req->timeout))
                                req->status = -ETIMEDOUT;
                        else if (req->status == -ENODATA)
@@ -363,32 +354,6 @@ static int addr_resolve_local(struct sockaddr *src_in,
        int ret;
 
        switch (dst_in->sa_family) {
-       case AF_INET:
-       {
-               __be32 src_ip = ((struct sockaddr_in *) src_in)->sin_addr.s_addr;
-               __be32 dst_ip = ((struct sockaddr_in *) dst_in)->sin_addr.s_addr;
-
-               dev = ip_dev_find(&init_net, dst_ip);
-               if (!dev)
-                       return -EADDRNOTAVAIL;
-
-               if (ipv4_is_zeronet(src_ip)) {
-                       src_in->sa_family = dst_in->sa_family;
-                       ((struct sockaddr_in *) src_in)->sin_addr.s_addr = dst_ip;
-                       ret = rdma_copy_addr(addr, dev, dev->dev_addr);
-               } else if (ipv4_is_loopback(src_ip)) {
-                       ret = rdma_translate_ip(dst_in, addr);
-                       if (!ret)
-                               memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
-               } else {
-                       ret = rdma_translate_ip(src_in, addr);
-                       if (!ret)
-                               memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
-               }
-               dev_put(dev);
-               break;
-       }
-
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
        case AF_INET6:
        {
@@ -473,7 +438,7 @@ int rdma_resolve_ip(struct rdma_addr_client *client,
 
        req->status = addr_resolve_local(src_in, dst_in, addr);
        if (req->status == -EADDRNOTAVAIL)
-               req->status = addr_resolve_remote(src_in, dst_in, addr);
+               req->status = addr_resolve(src_in, dst_in, addr);
 
        switch (req->status) {
        case 0: