[PATCH 09/39] wimax: provides user space with information needed when opening a WiMAX device

Inaky Perez-Gonzalez
2008-11-26T22:41:14Z

When user space wants to open a handle to a WiMAX device, it needs
information that is provided as a response to an "open" generic
netlink message.

Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
---
net/wimax/op-open.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 157 insertions(+), 0 deletions(-)
create mode 100644 net/wimax/op-open.c

diff --git a/net/wimax/op-open.c b/net/wimax/op-open.c
new file mode 100644
index 0000000..06c9cce
--- /dev/null
+++ b/net/wimax/op-open.c
@@ -0,0 +1,157 @@
+/*
+ * Linux WiMAX
+ * Netlink layer, open operation
+ *
+ *
+ * Copyright (C) 2005-2006 Intel Corporation <linux-wimax@intel.com>
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * Parse the open-handle command from user space.
+ *
+ * Accepts an "open" request from user space through generic netlink
+ * and replies to it with the information about internals that user
+ * space will need.
+ *
+ * This will only work if the device is in a state ready to accept
+ * user space intervention.
+ */
+#include <net/genetlink.h>
+#include <linux/wimax.h>
+#include <linux/security.h>
+#include "wimax-internal.h"
+
+#define D_SUBMODULE op_open
+#include "debug-levels.h"
+
+
+/*
+ * Authoritative source for the IFINFO attribute policy
+ *
+ * These attributes represent a struct that looks:
+ *
+ * MC_GROUPS: (nested) array of zero or more MC_GROUP
+ * MC_GROUP: nested MC_NAME and MC_ID
+ *
+ * We don't really use it here, but /me likes to keep the definition
+ * close to where the data is generated.
+ */
+/*
+static
+struct nla_policy wimax_gnl_ifinfo_policy[WIMAX_GNL_ATTR_MAX + 1] = {
+ [WIMAX_GNL_IFINFO_MC_GROUPS] = { .type = NLA_NESTED },
+ [WIMAX_GNL_IFINFO_MC_GROUP] = { .type = NLA_NESTED },
+ [WIMAX_GNL_IFINFO_MC_NAME] = {
+ .type = NLA_STRING,
+ .len = GENL_NAMSIZ
+ },
+ [WIMAX_GNL_IFINFO_MC_ID] = { .type = NLA_U16 },
+};
+*/
+
+
+static
+int __wimax_gnl_open_reply(struct wimax_dev *wimax_dev,
+ struct genl_info *genl_info)
+{
+ int result;
+ void *data;
+ struct sk_buff *reply_skb;
+ struct nlattr *nla_groups, *nla_group;
+ struct wimax_pipe *pipe_itr;
+
+ result = -ENOMEM;
+ reply_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (reply_skb == NULL)
+ goto error_new;
+ data = genlmsg_put_reply(reply_skb, genl_info,
+ &wimax_dev->gnl_family,
+ 0, WIMAX_GNL_RP_IFINFO);
+ if (data == NULL)
+ goto error_put_reply;
+
+ nla_groups = nla_nest_start(reply_skb, WIMAX_GNL_IFINFO_MC_GROUPS);
+ if (nla_groups == NULL)
+ goto error_groups_start;
+
+ list_for_each_entry(pipe_itr, &wimax_dev->pipe_list,
+ list_node) {
+ nla_group = nla_nest_start(reply_skb,
+ WIMAX_GNL_IFINFO_MC_GROUP);
+ if (nla_group == NULL)
+ goto error_group_start;
+
+ nla_put_u16(reply_skb, WIMAX_GNL_IFINFO_MC_ID,
+ pipe_itr->mcg.id);
+ nla_put_string(reply_skb, WIMAX_GNL_IFINFO_MC_NAME,
+ pipe_itr->mcg.name);
+ nla_nest_end(reply_skb, nla_group);
+ }
+ nla_nest_end(reply_skb, nla_groups);
+ genlmsg_end(reply_skb, data);
+
+ result = genlmsg_reply(reply_skb, genl_info);
+ if (result < 0)
+ goto error_reply;
+ return 0;
+
+error_group_start:
+error_groups_start:
+error_reply:
+error_put_reply:
+ nlmsg_free(reply_skb);
+error_new:
+ return result;
+}
+
+
+static
+int wimax_gnl_doit_open(struct sk_buff *skb, struct genl_info *info)
+{
+ int result;
+ struct wimax_dev *wimax_dev;
+
+ d_fnstart(3, NULL, "(skb %p info %p)\n", skb, info);
+ result = -EPERM;
+ if (security_netlink_recv(skb, CAP_NET_ADMIN))
+ goto error_perm;
+ result = -ENODEV;
+ wimax_dev = wimax_dev_get_by_genl_info(info);
+ if (wimax_dev == NULL)
+ goto error_no_wimax_dev;
+ mutex_lock(&wimax_dev->mutex);
+ result = wimax_dev_is_ready(wimax_dev);
+ if (result < 0)
+ goto error_not_ready;
+ result = __wimax_gnl_open_reply(wimax_dev, info);
+error_not_ready:
+ mutex_unlock(&wimax_dev->mutex);
+ dev_put(wimax_dev->net_dev);
+error_no_wimax_dev:
+error_perm:
+ d_fnend(3, NULL, "(skb %p info %p) = %d\n", skb, info, result);
+ return result;
+}
+
+
+struct genl_ops wimax_gnl_open = {
+ .cmd = WIMAX_GNL_OP_OPEN,
+ .flags = 0,
+ .policy = NULL,
+ .doit = wimax_gnl_doit_open,
+ .dumpit = NULL,
+};
--
1.5.6.5