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>

1 files changed, 23 insertions, 58 deletions

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index de5fe161a1b9..38a7184ea745 100644
--- 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: