From: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Allow userspace to issue a netlink query against the ib_device for
something like "uverbs" and get back the char dev name, inode major/minor,
and interface ABI information for "uverbs0".
Since we are now in netlink this can also trigger a module autoload to
make the uverbs device come into existence.
Largely this will let us replace searching and reading inside sysfs to
setup devices, and provides an alternative (using driver_id) to device
name based provider binding for things like rxe.
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
---
drivers/infiniband/core/core_priv.h | 9 +++
drivers/infiniband/core/device.c | 98 +++++++++++++++++++++++++++++
drivers/infiniband/core/nldev.c | 91 +++++++++++++++++++++++++++
include/rdma/ib_verbs.h | 4 ++
include/rdma/rdma_netlink.h | 2 +
include/uapi/rdma/rdma_netlink.h | 14 +++++
6 files changed, 218 insertions(+)
diff --git a/drivers/infiniband/core/core_priv.h b/drivers/infiniband/core/core_priv.h
index ff40a450b5d28e..a953c2fa2e7811 100644
--- a/drivers/infiniband/core/core_priv.h
+++ b/drivers/infiniband/core/core_priv.h
@@ -88,6 +88,15 @@ typedef int (*nldev_callback)(struct ib_device *device,
int ib_enum_all_devs(nldev_callback nldev_cb, struct sk_buff *skb,
struct netlink_callback *cb);
+struct ib_client_nl_info {
+ struct sk_buff *nl_msg;
+ struct device *cdev;
+ unsigned int port;
+ u64 abi;
+};
+int ib_get_client_nl_info(struct ib_device *ibdev, const char *client_name,
+ struct ib_client_nl_info *res);
+
enum ib_cache_gid_default_mode {
IB_CACHE_GID_DEFAULT_MODE_SET,
IB_CACHE_GID_DEFAULT_MODE_DELETE
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index abb169f31d0fe3..7db8566cdb8904 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -1726,6 +1726,104 @@ void ib_unregister_client(struct ib_client *client)
}
EXPORT_SYMBOL(ib_unregister_client);
+static int __ib_get_global_client_nl_info(const char *client_name,
+ struct ib_client_nl_info *res)
+{
+ struct ib_client *client;
+ unsigned long index;
+ int ret = -ENOENT;
+
+ down_read(&clients_rwsem);
+ xa_for_each_marked (&clients, index, client, CLIENT_REGISTERED) {
+ if (strcmp(client->name, client_name) != 0)
+ continue;
+ if (!client->get_global_nl_info) {
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ ret = client->get_global_nl_info(res);
+ if (WARN_ON(ret == -ENOENT))
+ ret = -EINVAL;
+ if (!ret && res->cdev)
+ get_device(res->cdev);
+ break;
+ }
+ up_read(&clients_rwsem);
+ return ret;
+}
+
+static int __ib_get_client_nl_info(struct ib_device *ibdev,
+ const char *client_name,
+ struct ib_client_nl_info *res)
+{
+ unsigned long index;
+ void *client_data;
+ int ret = -ENOENT;
+
+ down_read(&ibdev->client_data_rwsem);
+ xan_for_each_marked (&ibdev->client_data, index, client_data,
+ CLIENT_DATA_REGISTERED) {
+ struct ib_client *client = xa_load(&clients, index);
+
+ if (!client || strcmp(client->name, client_name) != 0)
+ continue;
+ if (!client->get_nl_info) {
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ ret = client->get_nl_info(ibdev, client_data, res);
+ if (WARN_ON(ret == -ENOENT))
+ ret = -EINVAL;
+
+ /*
+ * The cdev is guaranteed valid as long as we are inside the
+ * client_data_rwsem as remove_one can't be called. Keep it
+ * valid for the caller.
+ */
+ if (!ret && res->cdev)
+ get_device(res->cdev);
+ break;
+ }
+ up_read(&ibdev->client_data_rwsem);
+
+ return ret;
+}
+
+/**
+ * ib_get_client_nl_info - Fetch the nl_info from a client
+ * @device - IB device
+ * @client_name - Name of the client
+ * @res - Result of the query
+ */
+int ib_get_client_nl_info(struct ib_device *ibdev, const char *client_name,
+ struct ib_client_nl_info *res)
+{
+ int ret;
+
+ if (ibdev)
+ ret = __ib_get_client_nl_info(ibdev, client_name, res);
+ else
+ ret = __ib_get_global_client_nl_info(client_name, res);
+#ifdef CONFIG_MODULES
+ if (ret == -ENOENT) {
+ request_module("rdma-client-%s", client_name);
+ if (ibdev)
+ ret = __ib_get_client_nl_info(ibdev, client_name, res);
+ else
+ ret = __ib_get_global_client_nl_info(client_name, res);
+ }
+#endif
+ if (ret) {
+ if (ret == -ENOENT)
+ return -EOPNOTSUPP;
+ return ret;
+ }
+
+ if (WARN_ON(!res->cdev))
+ return -EINVAL;
+ return 0;
+}
+
/**
* ib_set_client_data - Set IB client context
* @device:Device to set context for
diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
index 69188cbbd99bd5..55eccea628e99f 100644
--- a/drivers/infiniband/core/nldev.c
+++ b/drivers/infiniband/core/nldev.c
@@ -120,6 +120,9 @@ static const struct nla_policy nldev_policy[RDMA_NLDEV_ATTR_MAX] = {
[RDMA_NLDEV_ATTR_DEV_PROTOCOL] = { .type = NLA_NUL_STRING,
.len = RDMA_NLDEV_ATTR_ENTRY_STRLEN },
[RDMA_NLDEV_NET_NS_FD] = { .type = NLA_U32 },
+ [RDMA_NLDEV_ATTR_CHARDEV_TYPE] = { .type = NLA_NUL_STRING,
+ .len = 128 },
+ [RDMA_NLDEV_ATTR_PORT_INDEX] = { .type = NLA_U32 },
};
static int put_driver_name_print_type(struct sk_buff *msg, const char *name,
@@ -1347,6 +1350,91 @@ static int nldev_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
return 0;
}
+static int nldev_get_chardev(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[RDMA_NLDEV_ATTR_MAX];
+ char client_name[IB_DEVICE_NAME_MAX];
+ struct ib_client_nl_info data = {};
+ struct ib_device *ibdev = NULL;
+ struct sk_buff *msg;
+ u32 index;
+ int err;
+
+ err = nlmsg_parse(nlh, 0, tb, RDMA_NLDEV_ATTR_MAX - 1, nldev_policy,
+ extack);
+ if (err || !tb[RDMA_NLDEV_ATTR_CHARDEV_TYPE])
+ return -EINVAL;
+
+ if (nla_strlcpy(client_name, tb[RDMA_NLDEV_ATTR_CHARDEV_TYPE],
+ sizeof(client_name)) >= sizeof(client_name))
+ return -EINVAL;
+
+ if (tb[RDMA_NLDEV_ATTR_DEV_INDEX]) {
+ index = nla_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]);
+ ibdev = ib_device_get_by_index(sock_net(skb->sk), index);
+ if (!ibdev)
+ return -EINVAL;
+
+ if (tb[RDMA_NLDEV_ATTR_PORT_INDEX]) {
+ data.port = nla_get_u32(tb[RDMA_NLDEV_ATTR_PORT_INDEX]);
+ if (!rdma_is_port_valid(ibdev, data.port)) {
+ err = -EINVAL;
+ goto out_put;
+ }
+ } else {
+ data.port = -1;
+ }
+ } else if (tb[RDMA_NLDEV_ATTR_PORT_INDEX]) {
+ return -EINVAL;
+ }
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg) {
+ err = -ENOMEM;
+ goto out_put;
+ }
+ nlh = nlmsg_put(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq,
+ RDMA_NL_GET_TYPE(RDMA_NL_NLDEV,
+ RDMA_NLDEV_CMD_GET_CHARDEV),
+ 0, 0);
+
+ data.nl_msg = msg;
+ err = ib_get_client_nl_info(ibdev, client_name, &data);
+ if (err)
+ goto out_nlmsg;
+
+ err = nla_put_u64_64bit(msg, RDMA_NLDEV_ATTR_CHARDEV,
+ huge_encode_dev(data.cdev->devt),
+ RDMA_NLDEV_ATTR_PAD);
+ if (err)
+ goto out_data;
+ err = nla_put_u64_64bit(msg, RDMA_NLDEV_ATTR_CHARDEV_ABI, data.abi,
+ RDMA_NLDEV_ATTR_PAD);
+ if (err)
+ goto out_data;
+ if (nla_put_string(msg, RDMA_NLDEV_ATTR_CHARDEV_NAME,
+ dev_name(data.cdev))) {
+ err = -EMSGSIZE;
+ goto out_data;
+ }
+
+ nlmsg_end(msg, nlh);
+ put_device(data.cdev);
+ if (ibdev)
+ ib_device_put(ibdev);
+ return rdma_nl_unicast(msg, NETLINK_CB(skb).portid);
+
+out_data:
+ put_device(data.cdev);
+out_nlmsg:
+ nlmsg_free(msg);
+out_put:
+ if (ibdev)
+ ib_device_put(ibdev);
+ return err;
+}
+
static int nldev_sys_get_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
@@ -1404,6 +1492,9 @@ static const struct rdma_nl_cbs nldev_cb_table[RDMA_NLDEV_NUM_OPS] = {
.doit = nldev_get_doit,
.dump = nldev_get_dumpit,
},
+ [RDMA_NLDEV_CMD_GET_CHARDEV] = {
+ .doit = nldev_get_chardev,
+ },
[RDMA_NLDEV_CMD_SET] = {
.doit = nldev_set_doit,
.flags = RDMA_NL_ADMIN_PERM,
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 973514ea17a79b..a1265e9ce2d11f 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2684,10 +2684,14 @@ struct ib_device {
u32 iw_driver_flags;
};
+struct ib_client_nl_info;
struct ib_client {
const char *name;
void (*add) (struct ib_device *);
void (*remove)(struct ib_device *, void *client_data);
+ int (*get_nl_info)(struct ib_device *ibdev, void *client_data,
+ struct ib_client_nl_info *res);
+ int (*get_global_nl_info)(struct ib_client_nl_info *res);
/* Returns the net_dev belonging to this ib_client and matching the
* given parameters.
diff --git a/include/rdma/rdma_netlink.h b/include/rdma/rdma_netlink.h
index 10732ab31ba2f9..c7acbe08342828 100644
--- a/include/rdma/rdma_netlink.h
+++ b/include/rdma/rdma_netlink.h
@@ -110,4 +110,6 @@ void rdma_link_register(struct rdma_link_ops *ops);
void rdma_link_unregister(struct rdma_link_ops *ops);
#define MODULE_ALIAS_RDMA_LINK(type) MODULE_ALIAS("rdma-link-" type)
+#define MODULE_ALIAS_RDMA_CLIENT(type) MODULE_ALIAS("rdma-client-" type)
+
#endif /* _RDMA_NETLINK_H */
diff --git a/include/uapi/rdma/rdma_netlink.h b/include/uapi/rdma/rdma_netlink.h
index f588e8551c6cea..9903db21a42c58 100644
--- a/include/uapi/rdma/rdma_netlink.h
+++ b/include/uapi/rdma/rdma_netlink.h
@@ -279,6 +279,8 @@ enum rdma_nldev_command {
RDMA_NLDEV_CMD_RES_PD_GET, /* can dump */
+ RDMA_NLDEV_CMD_GET_CHARDEV,
+
RDMA_NLDEV_NUM_OPS
};
@@ -491,6 +493,18 @@ enum rdma_nldev_attr {
*/
RDMA_NLDEV_NET_NS_FD, /* u32 */
+ /*
+ * Information about a chardev.
+ * CHARDEV_TYPE is the name of the chardev ABI (ie uverbs, umad, etc)
+ * CHARDEV_ABI signals the ABI revision (historical)
+ * CHARDEV_NAME is the kernel name for the /dev/ file (no directory)
+ * CHARDEV is the 64 bit dev_t for the inode
+ */
+ RDMA_NLDEV_ATTR_CHARDEV_TYPE, /* string */
+ RDMA_NLDEV_ATTR_CHARDEV_NAME, /* string */
+ RDMA_NLDEV_ATTR_CHARDEV_ABI, /* u64 */
+ RDMA_NLDEV_ATTR_CHARDEV, /* u64 */
+
/*
* Always the end
*/
--
2.21.0
