[PATCH 12/30] IB/cma: Add configfs for rdma_cm

Somnath Kotur
2015-02-19T22:02:27Z

From: Matan Barak <matanb-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>

Users would like to control the behaviour of rdma_cm.
For example, old applications which doesn't set the
required RoCE gid type could be executed on RoCE V2
network types. In order to support this configuration,
we implement a configfs for rdma_cm.

In order to use the configfs, one needs to mount it and
mkdir <IB device name> inside rdma_cm directory.

The patch adds support for a single configuration file,
default_roce_mode. The mode can either be IB & RoCEv1 or
RoCEv2.

Signed-off-by: Matan Barak <matanb-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Signed-off-by: Somnath Kotur <somnath.kotur-laKkSmNT4hbQT0dZR+AlfA@public.gmane.org>
---
drivers/infiniband/core/Makefile | 2 +-
drivers/infiniband/core/cma.c | 50 ++++++-
drivers/infiniband/core/cma_configfs.c | 222 ++++++++++++++++++++++++++++++
drivers/infiniband/core/core_priv.h | 13 ++
drivers/infiniband/core/roce_gid_cache.c | 13 ++
5 files changed, 295 insertions(+), 5 deletions(-)
create mode 100644 drivers/infiniband/core/cma_configfs.c

diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index 2c94963..50d2833 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -22,7 +22,7 @@ ib_cm-y := cm.o

iw_cm-y := iwcm.o iwpm_util.o iwpm_msg.o

-rdma_cm-y := cma.o
+rdma_cm-y := cma.o cma_configfs.o

rdma_ucm-y := ucma.o

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 9afa410..237f2dd 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -55,6 +55,7 @@
#include <rdma/ib_cm.h>
#include <rdma/ib_sa.h>
#include <rdma/iw_cm.h>
+#include "core_priv.h"

MODULE_AUTHOR("Sean Hefty");
MODULE_DESCRIPTION("Generic RDMA CM Agent");
@@ -91,6 +92,7 @@ struct cma_device {
struct completion comp;
atomic_t refcount;
struct list_head id_list;
+ enum ib_gid_type default_gid_type;
};

struct rdma_bind_list {
@@ -103,6 +105,42 @@ enum {
CMA_OPTION_AFONLY,
};

+void cma_ref_dev(struct cma_device *cma_dev)
+{
+ atomic_inc(&cma_dev->refcount);
+}
+
+struct cma_device *cma_enum_devices_by_ibdev(cma_device_filter filter,
+ void *cookie)
+{
+ struct cma_device *cma_dev;
+ struct cma_device *found_cma_dev = NULL;
+
+ mutex_lock(&lock);
+
+ list_for_each_entry(cma_dev, &dev_list, list)
+ if (filter(cma_dev->device, cookie)) {
+ found_cma_dev = cma_dev;
+ break;
+ }
+
+ if (found_cma_dev)
+ cma_ref_dev(found_cma_dev);
+ mutex_unlock(&lock);
+ return found_cma_dev;
+}
+
+enum ib_gid_type cma_get_default_gid_type(struct cma_device *cma_dev)
+{
+ return cma_dev->default_gid_type;
+}
+
+void cma_set_default_gid_type(struct cma_device *cma_dev,
+ enum ib_gid_type default_gid_type)
+{
+ cma_dev->default_gid_type = default_gid_type;
+}
+
/*
* Device removal can occur at anytime, so we need extra handling to
* serialize notifying the user of device removal with other callbacks.
@@ -248,15 +286,16 @@ static inline void cma_set_ip_ver(struct cma_hdr *hdr, u8 ip_ver)
static void cma_attach_to_dev(struct rdma_id_private *id_priv,
struct cma_device *cma_dev)
{
- atomic_inc(&cma_dev->refcount);
+ cma_ref_dev(cma_dev);
id_priv->cma_dev = cma_dev;
+ id_priv->gid_type = cma_dev->default_gid_type;
id_priv->id.device = cma_dev->device;
id_priv->id.route.addr.dev_addr.transport =
rdma_node_get_transport(cma_dev->device->node_type);
list_add_tail(&id_priv->list, &cma_dev->id_list);
}

-static inline void cma_deref_dev(struct cma_device *cma_dev)
+void cma_deref_dev(struct cma_device *cma_dev)
{
if (atomic_dec_and_test(&cma_dev->refcount))
complete(&cma_dev->comp);
@@ -385,7 +424,7 @@ static int cma_acquire_dev(struct rdma_id_private *id_priv,

ret = ib_find_cached_gid_by_port(cma_dev->device,
&iboe_gid,
- IB_GID_TYPE_IB,
+ cma_dev->default_gid_type,
port,
&init_net,
if_index,
@@ -418,7 +457,7 @@ static int cma_acquire_dev(struct rdma_id_private *id_priv,

ret = ib_find_cached_gid_by_port(cma_dev->device,
&iboe_gid,
- IB_GID_TYPE_IB,
+ cma_dev->default_gid_type,
port,
&init_net,
if_index,
@@ -3521,6 +3560,7 @@ static void cma_add_one(struct ib_device *device)
return;

cma_dev->device = device;
+ cma_dev->default_gid_type = IB_GID_TYPE_IB;

init_completion(&cma_dev->comp);
atomic_set(&cma_dev->refcount, 1);
@@ -3701,6 +3741,7 @@ static int __init cma_init(void)

if (ibnl_add_client(RDMA_NL_RDMA_CM, RDMA_NL_RDMA_CM_NUM_OPS, cma_cb_table))
printk(KERN_WARNING "RDMA CMA: failed to add netlink callback\n");
+ cma_configfs_init();

return 0;

@@ -3714,6 +3755,7 @@ err:

static void __exit cma_cleanup(void)
{
+ cma_configfs_exit();
ibnl_remove_client(RDMA_NL_RDMA_CM);
ib_unregister_client(&cma_client);
unregister_netdevice_notifier(&cma_nb);
diff --git a/drivers/infiniband/core/cma_configfs.c b/drivers/infiniband/core/cma_configfs.c
new file mode 100644
index 0000000..9a87210
--- /dev/null
+++ b/drivers/infiniband/core/cma_configfs.c
@@ -0,0 +1,222 @@
+/*
+ * Copyright (c) 2015, Mellanox Technologies 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.
+ */
+
+#include <linux/configfs.h>
+#include <rdma/ib_verbs.h>
+#include "core_priv.h"
+
+struct cma_device;
+
+struct cma_dev_group {
+ struct config_item item;
+};
+
+struct cma_configfs_attr {
+ struct configfs_attribute attr;
+ ssize_t (*show)(struct cma_device *cma_dev,
+ struct cma_dev_group *group,
+ char *buf);
+ ssize_t (*store)(struct cma_device *cma_dev,
+ struct cma_dev_group *group,
+ const char *buf, size_t count);
+};
+
+static struct cma_dev_group *to_dev_group(struct config_item *item)
+{
+ return item ?
+ container_of(item, struct cma_dev_group, item) :
+ NULL;
+}
+
+static ssize_t show_default_roce_mode(struct cma_device *cma_dev,
+ struct cma_dev_group *group,
+ char *buf)
+{
+ return sprintf(buf, "%s",
+ roce_gid_cache_type_str(cma_get_default_gid_type(cma_dev)));
+}
+
+static ssize_t store_default_roce_mode(struct cma_device *cma_dev,
+ struct cma_dev_group *group,
+ const char *buf, size_t count)
+{
+ int gid_type = roce_gid_cache_parse_gid_str(buf);
+
+ if (gid_type < 0)
+ return -EINVAL;
+
+ cma_set_default_gid_type(cma_dev, gid_type);
+
+ return strnlen(buf, count);
+}
+
+#define CMA_PARAM_ATTR_RW(_name) \
+static struct cma_configfs_attr cma_configfs_attr_##_name = \
+ __CONFIGFS_ATTR(_name, S_IRUGO | S_IWUSR, show_##_name, store_##_name)
+
+CMA_PARAM_ATTR_RW(default_roce_mode);
+
+static bool filter_by_name(struct ib_device *ib_dev, void *cookie)
+{
+ return !strcmp(ib_dev->name, cookie);
+}
+
+static ssize_t cma_configfs_attr_show(struct config_item *item,
+ struct configfs_attribute *attr,
+ char *buf)
+{
+ ssize_t ret = -EINVAL;
+ struct cma_device *cma_dev =
+ cma_enum_devices_by_ibdev(filter_by_name, config_item_name(item));
+ struct cma_dev_group *group = to_dev_group(item);
+ struct cma_configfs_attr *ca =
+ container_of(attr, struct cma_configfs_attr, attr);
+
+ if (!cma_dev)
+ return -ENODEV;
+
+ if (ca->show)
+ ret = ca->show(cma_dev, group, buf);
+
+ cma_deref_dev(cma_dev);
+ return ret;
+}
+
+static ssize_t cma_configfs_attr_store(struct config_item *item,
+ struct configfs_attribute *attr,
+ const char *buf, size_t count)
+{
+ ssize_t ret = -EINVAL;
+ struct cma_device *cma_dev =
+ cma_enum_devices_by_ibdev(filter_by_name, config_item_name(item));
+ struct cma_dev_group *group = to_dev_group(item);
+ struct cma_configfs_attr *ca =
+ container_of(attr, struct cma_configfs_attr, attr);
+
+ if (!cma_dev)
+ return -ENODEV;
+
+ if (ca->store)
+ ret = ca->store(cma_dev, group, buf, count);
+
+ cma_deref_dev(cma_dev);
+ return ret;
+}
+
+static struct configfs_attribute *cma_configfs_attributes[] = {
+ &cma_configfs_attr_default_roce_mode.attr,
+ NULL,
+};
+
+static void cma_configfs_attr_release(struct config_item *item)
+{
+ kfree(to_dev_group(item));
+}
+
+static struct configfs_item_operations cma_item_ops = {
+ .show_attribute = cma_configfs_attr_show,
+ .store_attribute = cma_configfs_attr_store,
+ .release = cma_configfs_attr_release,
+};
+
+static struct config_item_type cma_item_type = {
+ .ct_attrs = cma_configfs_attributes,
+ .ct_item_ops = &cma_item_ops,
+ .ct_owner = THIS_MODULE
+};
+
+static struct config_item *make_cma_dev(struct config_group *group,
+ const char *name)
+{
+ int err = -EINVAL;
+ struct cma_device *cma_dev = cma_enum_devices_by_ibdev(filter_by_name,
+ (void *)name);
+ struct cma_dev_group *cma_dev_group = NULL;
+
+ if (!cma_dev)
+ goto fail;
+
+ cma_dev_group = kzalloc(sizeof(*cma_dev_group), GFP_KERNEL);
+
+ if (!cma_dev_group) {
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ config_item_init_type_name(&cma_dev_group->item, name, &cma_item_type);
+
+ cma_deref_dev(cma_dev);
+ return &cma_dev_group->item;
+
+fail:
+ if (cma_dev)
+ cma_deref_dev(cma_dev);
+ kfree(cma_dev_group);
+ return ERR_PTR(err);
+}
+
+static void drop_cma_dev(struct config_group *group,
+ struct config_item *item)
+{
+ config_item_put(item);
+}
+
+static struct configfs_group_operations cma_subsys_group_ops = {
+ .make_item = make_cma_dev,
+ .drop_item = drop_cma_dev,
+};
+
+static struct config_item_type cma_subsys_type = {
+ .ct_group_ops = &cma_subsys_group_ops,
+ .ct_owner = THIS_MODULE,
+};
+
+static struct configfs_subsystem cma_subsys = {
+ .su_group = {
+ .cg_item = {
+ .ci_namebuf = "rdma_cm",
+ .ci_type = &cma_subsys_type,
+ },
+ },
+};
+
+int __init cma_configfs_init(void)
+{
+ config_group_init(&cma_subsys.su_group);
+ mutex_init(&cma_subsys.su_mutex);
+ return configfs_register_subsystem(&cma_subsys);
+}
+
+void __exit cma_configfs_exit(void)
+{
+ configfs_unregister_subsystem(&cma_subsys);
+}
diff --git a/drivers/infiniband/core/core_priv.h b/drivers/infiniband/core/core_priv.h
index fbe5922..8d68d73 100644
--- a/drivers/infiniband/core/core_priv.h
+++ b/drivers/infiniband/core/core_priv.h
@@ -39,6 +39,18 @@

#include <rdma/ib_verbs.h>

+int cma_configfs_init(void);
+void cma_configfs_exit(void);
+struct cma_device;
+typedef bool (*cma_device_filter)(struct ib_device *, void *);
+struct cma_device *cma_enum_devices_by_ibdev(cma_device_filter filter,
+ void *cookie);
+enum ib_gid_type cma_get_default_gid_type(struct cma_device *cma_dev);
+void cma_set_default_gid_type(struct cma_device *cma_dev,
+ enum ib_gid_type default_gid_type);
+void cma_ref_dev(struct cma_device *cma_dev);
+void cma_deref_dev(struct cma_device *cma_dev);
+
extern struct workqueue_struct *roce_gid_mgmt_wq;

int ib_device_register_sysfs(struct ib_device *device,
@@ -72,6 +84,7 @@ void ib_enum_roce_ports_of_netdev(roce_netdev_filter filter,
void *cookie);

const char *roce_gid_cache_type_str(enum ib_gid_type gid_type);
+int roce_gid_cache_parse_gid_str(const char *buf);

int roce_gid_cache_get_gid(struct ib_device *ib_dev, u8 port, int index,
union ib_gid *gid, struct ib_gid_attr *attr);
diff --git a/drivers/infiniband/core/roce_gid_cache.c b/drivers/infiniband/core/roce_gid_cache.c
index 6017ba0..575bffe 100644
--- a/drivers/infiniband/core/roce_gid_cache.c
+++ b/drivers/infiniband/core/roce_gid_cache.c
@@ -70,6 +70,19 @@ const char *roce_gid_cache_type_str(enum ib_gid_type gid_type)

return "Invalid GID type";
}
+EXPORT_SYMBOL_GPL(roce_gid_cache_type_str);
+
+int roce_gid_cache_parse_gid_str(const char *buf)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(gid_type_str); ++i)
+ if (gid_type_str[i] && !strcmp(buf, gid_type_str[i]))
+ return i;
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(roce_gid_cache_parse_gid_str);

static void put_ndev(struct rcu_head *rcu)
{