RDMA/ucma: Support querying for AF_IB addresses

The sockaddr structure for AF_IB is larger than sockaddr_in6.  The
rdma cm user space ABI uses the latter to exchange address information
between user space and the kernel.

To support querying for larger addresses, define a new query command
that exchanges data using sockaddr_storage, rather than sockaddr_in6.
Unlike the existing query_route command, the new command only returns
address information.  Route (i.e. path record) data is separated.

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

1 files changed, 74 insertions, 2 deletions

diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index e813774bf7a7..18bdccc0c2ec 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -47,6 +47,7 @@
 #include <rdma/ib_marshall.h>
 #include <rdma/rdma_cm.h>
 #include <rdma/rdma_cm_ib.h>
+#include <rdma/ib_addr.h>
 
 MODULE_AUTHOR("Sean Hefty");
 MODULE_DESCRIPTION("RDMA Userspace Connection Manager Access");
@@ -649,7 +650,7 @@ static ssize_t ucma_query_route(struct ucma_file *file,
                                 const char __user *inbuf,
                                 int in_len, int out_len)
 {
-        struct rdma_ucm_query_route cmd;
+        struct rdma_ucm_query cmd;
         struct rdma_ucm_query_route_resp resp;
         struct ucma_context *ctx;
         struct sockaddr *addr;
@@ -709,6 +710,76 @@ out:
         return ret;
 }
 
+static void ucma_query_device_addr(struct rdma_cm_id *cm_id,
+                                   struct rdma_ucm_query_addr_resp *resp)
+{
+        if (!cm_id->device)
+                return;
+
+        resp->node_guid = (__force __u64) cm_id->device->node_guid;
+        resp->port_num = cm_id->port_num;
+        resp->pkey = (__force __u16) cpu_to_be16(
+                     ib_addr_get_pkey(&cm_id->route.addr.dev_addr));
+}
+
+static ssize_t ucma_query_addr(struct ucma_context *ctx,
+                               void __user *response, int out_len)
+{
+        struct rdma_ucm_query_addr_resp resp;
+        struct sockaddr *addr;
+        int ret = 0;
+
+        if (out_len < sizeof(resp))
+                return -ENOSPC;
+
+        memset(&resp, 0, sizeof resp);
+
+        addr = (struct sockaddr *) &ctx->cm_id->route.addr.src_addr;
+        resp.src_size = rdma_addr_size(addr);
+        memcpy(&resp.src_addr, addr, resp.src_size);
+
+        addr = (struct sockaddr *) &ctx->cm_id->route.addr.dst_addr;
+        resp.dst_size = rdma_addr_size(addr);
+        memcpy(&resp.dst_addr, addr, resp.dst_size);
+
+        ucma_query_device_addr(ctx->cm_id, &resp);
+
+        if (copy_to_user(response, &resp, sizeof(resp)))
+                ret = -EFAULT;
+
+        return ret;
+}
+
+static ssize_t ucma_query(struct ucma_file *file,
+                          const char __user *inbuf,
+                          int in_len, int out_len)
+{
+        struct rdma_ucm_query cmd;
+        struct ucma_context *ctx;
+        void __user *response;
+        int ret;
+
+        if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
+                return -EFAULT;
+
+        response = (void __user *)(unsigned long) cmd.response;
+        ctx = ucma_get_ctx(file, cmd.id);
+        if (IS_ERR(ctx))
+                return PTR_ERR(ctx);
+
+        switch (cmd.option) {
+        case RDMA_USER_CM_QUERY_ADDR:
+                ret = ucma_query_addr(ctx, response, out_len);
+                break;
+        default:
+                ret = -ENOSYS;
+                break;
+        }
+
+        ucma_put_ctx(ctx);
+        return ret;
+}
+
 static void ucma_copy_conn_param(struct rdma_cm_id *id,
                                  struct rdma_conn_param *dst,
                                  struct rdma_ucm_conn_param *src)
@@ -1241,7 +1312,8 @@ static ssize_t (*ucma_cmd_table[])(struct ucma_file *file,
         [RDMA_USER_CM_CMD_NOTIFY]       = ucma_notify,
         [RDMA_USER_CM_CMD_JOIN_MCAST]   = ucma_join_multicast,
         [RDMA_USER_CM_CMD_LEAVE_MCAST]  = ucma_leave_multicast,
-        [RDMA_USER_CM_CMD_MIGRATE_ID]   = ucma_migrate_id
+        [RDMA_USER_CM_CMD_MIGRATE_ID]   = ucma_migrate_id,
+        [RDMA_USER_CM_CMD_QUERY]        = ucma_query
 };
 
 static ssize_t ucma_write(struct file *filp, const char __user *buf,