RDMA: Add netlink infrastructure
Add basic RDMA netlink infrastructure that allows for registration of
RDMA clients for which data is to be exported and supplies message
construction callbacks.
Signed-off-by: Nir Muchtar <nirm@voltaire.com>
[ Reorganize a few things, add CONFIG_NET dependency. - Roland ]
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/core/netlink.c b/drivers/infiniband/core/netlink.c
new file mode 100644
index 0000000..4a5abaf
--- /dev/null
+++ b/drivers/infiniband/core/netlink.c
@@ -0,0 +1,190 @@
+/*
+ * Copyright (c) 2010 Voltaire Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#define pr_fmt(fmt) "%s:%s: " fmt, KBUILD_MODNAME, __func__
+
+#include <net/netlink.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <rdma/rdma_netlink.h>
+
+struct ibnl_client {
+ struct list_head list;
+ int index;
+ int nops;
+ const struct ibnl_client_cbs *cb_table;
+};
+
+static DEFINE_MUTEX(ibnl_mutex);
+static struct sock *nls;
+static LIST_HEAD(client_list);
+
+int ibnl_add_client(int index, int nops,
+ const struct ibnl_client_cbs cb_table[])
+{
+ struct ibnl_client *cur;
+ struct ibnl_client *nl_client;
+
+ nl_client = kmalloc(sizeof *nl_client, GFP_KERNEL);
+ if (!nl_client)
+ return -ENOMEM;
+
+ nl_client->index = index;
+ nl_client->nops = nops;
+ nl_client->cb_table = cb_table;
+
+ mutex_lock(&ibnl_mutex);
+
+ list_for_each_entry(cur, &client_list, list) {
+ if (cur->index == index) {
+ pr_warn("Client for %d already exists\n", index);
+ mutex_unlock(&ibnl_mutex);
+ kfree(nl_client);
+ return -EINVAL;
+ }
+ }
+
+ list_add_tail(&nl_client->list, &client_list);
+
+ mutex_unlock(&ibnl_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL(ibnl_add_client);
+
+int ibnl_remove_client(int index)
+{
+ struct ibnl_client *cur, *next;
+
+ mutex_lock(&ibnl_mutex);
+ list_for_each_entry_safe(cur, next, &client_list, list) {
+ if (cur->index == index) {
+ list_del(&(cur->list));
+ mutex_unlock(&ibnl_mutex);
+ kfree(cur);
+ return 0;
+ }
+ }
+ pr_warn("Can't remove callback for client idx %d. Not found\n", index);
+ mutex_unlock(&ibnl_mutex);
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL(ibnl_remove_client);
+
+void *ibnl_put_msg(struct sk_buff *skb, struct nlmsghdr **nlh, int seq,
+ int len, int client, int op)
+{
+ unsigned char *prev_tail;
+
+ prev_tail = skb_tail_pointer(skb);
+ *nlh = NLMSG_NEW(skb, 0, seq, RDMA_NL_GET_TYPE(client, op),
+ len, NLM_F_MULTI);
+ (*nlh)->nlmsg_len = skb_tail_pointer(skb) - prev_tail;
+ return NLMSG_DATA(*nlh);
+
+nlmsg_failure:
+ nlmsg_trim(skb, prev_tail);
+ return NULL;
+}
+EXPORT_SYMBOL(ibnl_put_msg);
+
+int ibnl_put_attr(struct sk_buff *skb, struct nlmsghdr *nlh,
+ int len, void *data, int type)
+{
+ unsigned char *prev_tail;
+
+ prev_tail = skb_tail_pointer(skb);
+ NLA_PUT(skb, type, len, data);
+ nlh->nlmsg_len += skb_tail_pointer(skb) - prev_tail;
+ return 0;
+
+nla_put_failure:
+ nlmsg_trim(skb, prev_tail - nlh->nlmsg_len);
+ return -EMSGSIZE;
+}
+EXPORT_SYMBOL(ibnl_put_attr);
+
+static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+ struct ibnl_client *client;
+ int type = nlh->nlmsg_type;
+ int index = RDMA_NL_GET_CLIENT(type);
+ int op = RDMA_NL_GET_OP(type);
+
+ list_for_each_entry(client, &client_list, list) {
+ if (client->index == index) {
+ if (op < 0 || op >= client->nops ||
+ !client->cb_table[RDMA_NL_GET_OP(op)].dump)
+ return -EINVAL;
+ return netlink_dump_start(nls, skb, nlh,
+ client->cb_table[op].dump,
+ NULL);
+ }
+ }
+
+ pr_info("Index %d wasn't found in client list\n", index);
+ return -EINVAL;
+}
+
+static void ibnl_rcv(struct sk_buff *skb)
+{
+ mutex_lock(&ibnl_mutex);
+ netlink_rcv_skb(skb, &ibnl_rcv_msg);
+ mutex_unlock(&ibnl_mutex);
+}
+
+int __init ibnl_init(void)
+{
+ nls = netlink_kernel_create(&init_net, NETLINK_RDMA, 0, ibnl_rcv,
+ NULL, THIS_MODULE);
+ if (!nls) {
+ pr_warn("Failed to create netlink socket\n");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+void ibnl_cleanup(void)
+{
+ struct ibnl_client *cur, *next;
+
+ mutex_lock(&ibnl_mutex);
+ list_for_each_entry_safe(cur, next, &client_list, list) {
+ list_del(&(cur->list));
+ kfree(cur);
+ }
+ mutex_unlock(&ibnl_mutex);
+
+ netlink_kernel_release(nls);
+}