diff mbox

[18/28] ibnbd_clt: add sysfs interface

Message ID 1490352343-20075-19-git-send-email-jinpu.wangl@profitbricks.com (mailing list archive)
State RFC
Headers show

Commit Message

Jinpu Wang March 24, 2017, 10:45 a.m. UTC
From: Jack Wang <jinpu.wang@profitbricks.com>

Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Kleber Souza <kleber.souza@profitbricks.com>
Signed-off-by: Danil Kipnis <danil.kipnis@profitbricks.com>
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
---
 drivers/block/ibnbd_client/ibnbd_clt_sysfs.c | 863 +++++++++++++++++++++++++++
 drivers/block/ibnbd_client/ibnbd_clt_sysfs.h |  64 ++
 2 files changed, 927 insertions(+)
 create mode 100644 drivers/block/ibnbd_client/ibnbd_clt_sysfs.c
 create mode 100644 drivers/block/ibnbd_client/ibnbd_clt_sysfs.h
diff mbox

Patch

diff --git a/drivers/block/ibnbd_client/ibnbd_clt_sysfs.c b/drivers/block/ibnbd_client/ibnbd_clt_sysfs.c
new file mode 100644
index 0000000..89d487c
--- /dev/null
+++ b/drivers/block/ibnbd_client/ibnbd_clt_sysfs.c
@@ -0,0 +1,863 @@ 
+/*
+ * InfiniBand Network Block Driver
+ *
+ * Copyright (c) 2014 - 2017 ProfitBricks GmbH. All rights reserved.
+ * Authors: Fabian Holler < mail@fholler.de>
+ *          Jack Wang <jinpu.wang@profitbricks.com>
+ *   	    Kleber Souza <kleber.souza@profitbricks.com>
+ * 	    Danil Kipnis <danil.kipnis@profitbricks.com>
+ *   	    Roman Pen <roman.penyaev@profitbricks.com>
+ *          Milind Dumbare <Milind.dumbare@gmail.com>
+ *
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/parser.h>
+#include <linux/module.h>
+#include "ibnbd_clt_sysfs.h"
+#include "ibnbd_clt.h"
+#include <rdma/ibtrs.h>
+#include <rdma/ib.h>
+
+static struct kobject *ibnbd_kobject;
+static struct kobject *ibnbd_devices_kobject;
+static DEFINE_MUTEX(sess_lock);
+
+struct ibnbd_clt_dev_destroy_kobj_work {
+	struct ibnbd_dev	*dev;
+	struct work_struct	work;
+};
+
+enum {
+	IBNBD_OPT_ERR		= 0,
+	IBNBD_OPT_SERVER	= 1 << 0,
+	IBNBD_OPT_DEV_PATH	= 1 << 1,
+	IBNBD_OPT_ACCESS_MODE	= 1 << 3,
+	IBNBD_OPT_INPUT_MODE	= 1 << 4,
+	IBNBD_OPT_IO_MODE	= 1 << 5,
+};
+
+static unsigned ibnbd_opt_mandatory[] = {
+	IBNBD_OPT_SERVER,
+	IBNBD_OPT_DEV_PATH,
+};
+
+static const match_table_t ibnbd_opt_tokens = {
+	{	IBNBD_OPT_SERVER,	"server=%s"		},
+	{	IBNBD_OPT_DEV_PATH,	"device_path=%s"	},
+	{	IBNBD_OPT_ACCESS_MODE,	"access_mode=%s"	},
+	{	IBNBD_OPT_INPUT_MODE,	"input_mode=%s"		},
+	{	IBNBD_OPT_IO_MODE,	"io_mode=%s"		},
+	{	IBNBD_OPT_ERR,		NULL			},
+};
+
+/* remove new line from string */
+static void strip(char *s)
+{
+	char *p = s;
+
+	while (*s != '\0') {
+		if (*s != '\n')
+			*p++ = *s++;
+		else
+			++s;
+	}
+	*p = '\0';
+}
+
+static int ibnbd_clt_parse_map_options(const char *buf, char *server_addr,
+				       char *pathname,
+				       enum ibnbd_access_mode *access_mode,
+				       enum ibnbd_queue_mode *queue_mode,
+				       enum ibnbd_io_mode *io_mode)
+{
+	char *options, *sep_opt;
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+	int opt_mask = 0;
+	int token;
+	int ret = -EINVAL;
+	int i;
+
+	options = kstrdup(buf, GFP_KERNEL);
+	if (!options)
+		return -ENOMEM;
+
+	options = strstrip(options);
+	strip(options);
+	sep_opt = options;
+	while ((p = strsep(&sep_opt, " ")) != NULL) {
+		if (!*p)
+			continue;
+
+		token = match_token(p, ibnbd_opt_tokens, args);
+		opt_mask |= token;
+
+		switch (token) {
+		case IBNBD_OPT_SERVER:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			if (strlen(p) > IBTRS_ADDRLEN) {
+				ERR_NP("map_device: Server address too long\n");
+				ret = -EINVAL;
+				goto out;
+			}
+			strlcpy(server_addr, p, IBTRS_ADDRLEN);
+			kfree(p);
+			break;
+
+		case IBNBD_OPT_DEV_PATH:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			if (strlen(p) > NAME_MAX) {
+				ERR_NP("map_device: Device path too long\n");
+				ret = -EINVAL;
+				goto out;
+			}
+			strlcpy(pathname, p, NAME_MAX);
+			kfree(p);
+			break;
+
+		case IBNBD_OPT_ACCESS_MODE:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+
+			if (!strcmp(p, "ro")) {
+				*access_mode = IBNBD_ACCESS_RO;
+			} else if (!strcmp(p, "rw")) {
+				*access_mode = IBNBD_ACCESS_RW;
+			} else if (!strcmp(p, "migration")) {
+				*access_mode = IBNBD_ACCESS_MIGRATION;
+			} else {
+				ERR_NP("map_device: Invalid access_mode:"
+				       " '%s'\n", p);
+				ret = -EINVAL;
+				kfree(p);
+				goto out;
+			}
+
+			kfree(p);
+			break;
+
+		case IBNBD_OPT_INPUT_MODE:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			if (!strcmp(p, "mq")) {
+				*queue_mode = BLK_MQ;
+			} else if (!strcmp(p, "rq")) {
+				*queue_mode = BLK_RQ;
+			} else {
+				ERR_NP("map_device: Invalid input_mode: "
+				       "'%s'.\n", p);
+				ret = -EINVAL;
+				kfree(p);
+				goto out;
+			}
+			kfree(p);
+			break;
+
+		case IBNBD_OPT_IO_MODE:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			if (!strcmp(p, "blockio")) {
+				*io_mode = IBNBD_BLOCKIO;
+			} else if (!strcmp(p, "fileio")) {
+				*io_mode = IBNBD_FILEIO;
+			} else {
+				ERR_NP("map_device: Invalid io_mode: '%s'.\n",
+				       p);
+				ret = -EINVAL;
+				kfree(p);
+				goto out;
+			}
+			kfree(p);
+			break;
+
+		default:
+			ERR_NP("map_device: Unknown parameter or missing value"
+			       " '%s'\n", p);
+			ret = -EINVAL;
+			goto out;
+		}
+	}
+
+	for (i = 0; i < ARRAY_SIZE(ibnbd_opt_mandatory); i++) {
+		if ((opt_mask & ibnbd_opt_mandatory[i])) {
+			ret = 0;
+		} else {
+			ERR_NP("map_device: Parameters missing\n");
+			ret = -EINVAL;
+			break;
+		}
+	}
+
+out:
+	kfree(options);
+	return ret;
+}
+
+int ibnbd_clt_get_sess(struct ibnbd_session *sess)
+{
+	return kref_get_unless_zero(&sess->refcount);
+}
+
+void ibnbd_clt_put_sess(struct ibnbd_session *sess)
+{
+	mutex_lock(&sess_lock);
+	kref_put(&sess->refcount, ibnbd_clt_sess_release);
+	mutex_unlock(&sess_lock);
+}
+
+static void ibnbd_clt_dev_destroy_kobjs(struct ibnbd_dev *dev)
+{
+	kobject_del(&dev->kobj);
+	kobject_put(&dev->kobj);
+}
+
+static ssize_t ibnbd_clt_state_show(struct kobject *kobj,
+				    struct kobj_attribute *attr, char *page)
+{
+	struct ibnbd_dev *dev = container_of(kobj, struct ibnbd_dev, kobj);
+
+	switch (dev->dev_state) {
+	case (DEV_STATE_INIT):
+		return scnprintf(page, PAGE_SIZE, "init\n");
+	case (DEV_STATE_OPEN):
+		return scnprintf(page, PAGE_SIZE, "open\n");
+	case (DEV_STATE_CLOSED):
+		return scnprintf(page, PAGE_SIZE, "closed\n");
+	case (DEV_STATE_UNMAPPED):
+		return scnprintf(page, PAGE_SIZE, "unmapped\n");
+	default:
+		return scnprintf(page, PAGE_SIZE, "unknown\n");
+	}
+}
+
+static struct kobj_attribute ibnbd_clt_state_attr =
+	__ATTR(state, 0444, ibnbd_clt_state_show, NULL);
+
+static ssize_t ibnbd_clt_input_mode_show(struct kobject *kobj,
+					 struct kobj_attribute *attr,
+					 char *page)
+{
+	struct ibnbd_dev *dev = container_of(kobj, struct ibnbd_dev, kobj);
+
+	return scnprintf(page, PAGE_SIZE, "%s\n",
+			 ibnbd_queue_mode_str(dev->queue_mode));
+}
+
+static struct kobj_attribute ibnbd_clt_input_mode_attr =
+	__ATTR(input_mode, 0444, ibnbd_clt_input_mode_show, NULL);
+
+static ssize_t ibnbd_clt_mapping_path_show(struct kobject *kobj,
+					   struct kobj_attribute *attr,
+					   char *page)
+{
+	struct ibnbd_dev *dev;
+
+	dev = container_of(kobj, struct ibnbd_dev, kobj);
+
+	return scnprintf(page, PAGE_SIZE, "%s\n", dev->pathname);
+}
+
+static struct kobj_attribute ibnbd_clt_mapping_path_attr =
+	__ATTR(mapping_path, 0444, ibnbd_clt_mapping_path_show, NULL);
+
+static ssize_t ibnbd_clt_io_mode_show(struct kobject *kobj,
+				      struct kobj_attribute *attr, char *page)
+{
+	struct ibnbd_dev *dev = container_of(kobj, struct ibnbd_dev, kobj);
+
+	return scnprintf(page, PAGE_SIZE, "%s\n",
+			 ibnbd_io_mode_str(dev->remote_io_mode));
+}
+
+static struct kobj_attribute ibnbd_clt_io_mode =
+	__ATTR(io_mode, 0444, ibnbd_clt_io_mode_show, NULL);
+
+static ssize_t ibnbd_clt_unmap_dev_show(struct kobject *kobj,
+					struct kobj_attribute *attr, char *page)
+{
+	return scnprintf(page, PAGE_SIZE, "Usage: echo <normal|force> > %s\n",
+			 attr->attr.name);
+}
+
+static void ibnbd_clt_dev_kobj_destroy_worker(struct work_struct *work)
+{
+	struct ibnbd_clt_dev_destroy_kobj_work *destroy_work;
+	struct ibnbd_dev *dev;
+
+	destroy_work = container_of(work,
+				    struct ibnbd_clt_dev_destroy_kobj_work,
+				    work);
+	dev = destroy_work->dev;
+	kobject_get(&dev->kobj);
+	ibnbd_clt_dev_destroy_kobjs(dev);
+	kobject_put(&dev->kobj);
+	kfree(destroy_work);
+}
+
+void ibnbd_clt_schedule_dev_destroy(struct ibnbd_dev *dev)
+{
+	struct ibnbd_clt_dev_destroy_kobj_work *destroy_work = NULL;
+
+	/* memory allocation cannot fail, otherwise the last reference to the
+	 * session will never be put
+	 */
+	while (!destroy_work) {
+		destroy_work = kmalloc(sizeof(*destroy_work),
+				       (GFP_KERNEL | __GFP_REPEAT));
+		if (!destroy_work)
+			cond_resched();
+	}
+
+	destroy_work->dev = dev;
+	INIT_WORK(&destroy_work->work, ibnbd_clt_dev_kobj_destroy_worker);
+	if (WARN(!schedule_work(&destroy_work->work),
+		 "failed to schedule work\n"))
+		kfree(destroy_work);
+}
+
+static ssize_t ibnbd_clt_unmap_dev_store(struct kobject *kobj,
+					 struct kobj_attribute *attr,
+					 const char *buf, size_t count)
+{
+	int err;
+	struct ibnbd_dev *dev;
+	bool force;
+	char *options;
+
+	if (!try_module_get(THIS_MODULE))
+		return -ENODEV;
+	options = kstrdup(buf, GFP_KERNEL);
+	if (!options)
+		return -ENOMEM;
+
+	options = strstrip(options);
+	strip(options);
+
+	dev = container_of(kobj, struct ibnbd_dev, kobj);
+
+	if (dev->dev_state == DEV_STATE_UNMAPPED) {
+		err = -EALREADY;
+		goto out;
+	}
+
+	if (sysfs_streq(options, "normal")) {
+		force = false;
+	} else if (sysfs_streq(options, "force")) {
+		force = true;
+	} else {
+		ERR(dev, "unmap_device: Invalid value: %s\n", options);
+		err = -EINVAL;
+		goto out;
+	}
+
+	INFO(dev, "Unmapping device, option: %s.\n",
+	     force ? "force" : "normal");
+
+	err = ibnbd_close_device(dev, force);
+	if (err) {
+		ERR(dev, "unmap_device: Failed to close device, errno: %d\n",
+		    err);
+		goto out;
+	}
+
+	wait_for_completion(dev->close_compl);
+
+	ibnbd_clt_schedule_dev_destroy(dev);
+
+	module_put(THIS_MODULE);
+	kfree(options);
+	return count;
+out:
+	module_put(THIS_MODULE);
+	kfree(options);
+	return err;
+}
+
+static struct kobj_attribute ibnbd_clt_unmap_device_attr =
+	__ATTR(unmap_device, 0644, ibnbd_clt_unmap_dev_show,
+	       ibnbd_clt_unmap_dev_store);
+
+static ssize_t ibnbd_clt_remap_dev_show(struct kobject *kobj,
+					struct kobj_attribute *attr, char *page)
+{
+	return scnprintf(page, PAGE_SIZE, "Usage: echo <1> > %s\n",
+			 attr->attr.name);
+}
+
+static ssize_t ibnbd_clt_remap_dev_store(struct kobject *kobj,
+					 struct kobj_attribute *attr,
+					 const char *buf, size_t count)
+{
+	int err;
+	struct ibnbd_dev *dev;
+	char *options;
+
+	options = kstrdup(buf, GFP_KERNEL);
+	if (!options)
+		return -ENOMEM;
+
+	options = strstrip(options);
+	strip(options);
+
+	dev = container_of(kobj, struct ibnbd_dev, kobj);
+	if (!sysfs_streq(options, "1")) {
+		ERR(dev, "remap_device: Invalid value: %s\n", options);
+		err = -EINVAL;
+		goto out;
+	}
+
+	mutex_lock(&dev->lock);
+	if (dev->dev_state == DEV_STATE_UNMAPPED) {
+		err = -EIO;
+		mutex_unlock(&dev->lock);
+		goto out;
+	} else if (dev->dev_state == DEV_STATE_OPEN) {
+		mutex_unlock(&dev->lock);
+		goto out1;
+	} else if (dev->dev_state == DEV_STATE_CLOSED) {
+		mutex_unlock(&dev->lock);
+		INFO(dev, "Remapping device.\n");
+
+		err = open_remote_device(dev);
+		if (err) {
+			ERR(dev, "remap_device: Failed to remap device,"
+			    " errno: %d\n", err);
+			goto out;
+		}
+	}
+
+out1:
+	kfree(options);
+	return count;
+out:
+	kfree(options);
+	return err;
+}
+
+static struct kobj_attribute ibnbd_clt_remap_device_attr =
+	__ATTR(remap_device, 0644, ibnbd_clt_remap_dev_show,
+	       ibnbd_clt_remap_dev_store);
+
+static ssize_t ibnbd_clt_session_show(struct kobject *kobj,
+				      struct kobj_attribute *attr,
+				      char *page)
+{
+	struct ibnbd_dev *dev = container_of(kobj, struct ibnbd_dev, kobj);
+	char server_addr[IBTRS_ADDRLEN];
+	int ret;
+
+	if (dev->dev_state == DEV_STATE_UNMAPPED)
+		return -EIO;
+
+	ret = ibtrs_addr_to_str(&dev->sess->addr, server_addr,
+				sizeof(server_addr));
+
+	if (ret >= sizeof(server_addr))
+		return -ENOBUFS;
+	if (ret < 0)
+		return ret;
+
+	return scnprintf(page, PAGE_SIZE, "%s\n", server_addr);
+}
+
+static struct kobj_attribute ibnbd_clt_session_attr =
+	__ATTR(session, 0444, ibnbd_clt_session_show, NULL);
+
+static struct attribute *ibnbd_dev_attrs[] = {
+	&ibnbd_clt_unmap_device_attr.attr,
+	&ibnbd_clt_remap_device_attr.attr,
+	&ibnbd_clt_mapping_path_attr.attr,
+	&ibnbd_clt_state_attr.attr,
+	&ibnbd_clt_input_mode_attr.attr,
+	&ibnbd_clt_session_attr.attr,
+	&ibnbd_clt_io_mode.attr,
+	NULL,
+};
+
+void ibnbd_clt_remove_dev_symlink(struct ibnbd_dev *dev)
+{
+	if (strlen(dev->blk_symlink_name))
+		sysfs_remove_link(ibnbd_devices_kobject, dev->blk_symlink_name);
+}
+
+static void ibnbd_clt_dev_release(struct kobject *kobj)
+{
+	struct ibnbd_dev *dev;
+
+	dev = container_of(kobj, struct ibnbd_dev, kobj);
+	ibnbd_destroy_gen_disk(dev);
+}
+
+static struct kobj_type ibnbd_dev_ktype = {
+	.sysfs_ops      = &kobj_sysfs_ops,
+	.default_attrs  = ibnbd_dev_attrs,
+	.release	= ibnbd_clt_dev_release,
+};
+
+static int ibnbd_clt_add_dev_kobj(struct ibnbd_dev *dev)
+{
+	int ret;
+	struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
+
+	ret = kobject_init_and_add(&dev->kobj, &ibnbd_dev_ktype, gd_kobj, "%s",
+				   "ibnbd");
+	if (ret)
+		ERR(dev, "Failed to create device sysfs dir, errno: %d\n", ret);
+
+	return ret;
+}
+
+static int ibnbd_clt_str_ipv4_to_sockaddr(const char *con_addr,
+					  struct sockaddr_storage *dst)
+{
+	int ret;
+	char ipaddr[INET6_ADDRSTRLEN];
+	struct sockaddr_in *dst_sin = (struct sockaddr_in *)dst;
+	u8 ip4[4];
+
+	strlcpy(ipaddr, &con_addr[IP_PREFIX_LEN], sizeof(ipaddr));
+
+	ret = in4_pton(ipaddr, strlen(ipaddr), ip4, '\0', NULL);
+	if (ret == 0)
+		return -EINVAL;
+
+	memcpy(&dst_sin->sin_addr.s_addr, ip4,
+	       sizeof(dst_sin->sin_addr.s_addr));
+	dst_sin->sin_family = AF_INET;
+	dst_sin->sin_port = htons(IBTRS_SERVER_PORT);
+
+	return 0;
+}
+
+static int ibnbd_clt_str_ipv6_to_sockaddr(const char *con_addr,
+					  struct sockaddr_storage *dst)
+{
+	int ret;
+	char ipaddr[INET6_ADDRSTRLEN];
+	struct sockaddr_in6 *dst_sin6 = (struct sockaddr_in6 *)dst;
+
+	strlcpy(ipaddr, &con_addr[IP_PREFIX_LEN], sizeof(ipaddr));
+
+	ret = in6_pton(ipaddr, strlen(ipaddr),
+		       dst_sin6->sin6_addr.s6_addr,
+		       '\0', NULL);
+	if (ret != 1)
+		return -EINVAL;
+
+	dst_sin6->sin6_family = AF_INET6;
+	dst_sin6->sin6_port = htons(IBTRS_SERVER_PORT);
+
+	return 0;
+}
+
+static int ibnbd_clt_str_gid_to_sockaddr(const char *con_addr,
+					 struct sockaddr_storage *dst)
+{
+	int ret;
+	char gid[INET6_ADDRSTRLEN];
+	struct sockaddr_ib *dst_ib = (struct sockaddr_ib *)dst;
+
+	strlcpy(gid, &con_addr[GID_PREFIX_LEN], sizeof(gid));
+
+	/* We can use some of the I6 functions since GID is a valid
+	 * IPv6 address format
+	 */
+	ret = in6_pton(gid, strlen(gid),
+		       dst_ib->sib_addr.sib_raw, '\0', NULL);
+	if (ret == 0)
+		return -EINVAL;
+
+	dst_ib->sib_family = AF_IB;
+	/*
+	 * Use the same TCP server port number as the IB service ID
+	 * on the IB port space range
+	 */
+	dst_ib->sib_sid = cpu_to_be64(RDMA_IB_IP_PS_IB | IBTRS_SERVER_PORT);
+	dst_ib->sib_sid_mask = cpu_to_be64(0xffffffffffffffffULL);
+	dst_ib->sib_pkey = cpu_to_be16(0xffff);
+
+	return 0;
+}
+
+static int ibnbd_clt_str_to_sockaddr(char *addr,
+				     struct sockaddr_storage *sockaddr)
+{
+	if (strncmp(addr, GID_PREFIX, GID_PREFIX_LEN) == 0) {
+		return ibnbd_clt_str_gid_to_sockaddr(addr, sockaddr);
+	} else if (strncmp(addr, IP_PREFIX, IP_PREFIX_LEN) == 0) {
+		if (ibnbd_clt_str_ipv4_to_sockaddr(addr, sockaddr))
+			return ibnbd_clt_str_ipv6_to_sockaddr(addr, sockaddr);
+		else
+			return 0;
+	}
+	return -EPROTONOSUPPORT;
+}
+
+static struct ibnbd_session *
+ibnbd_clt_get_create_sess(struct sockaddr_storage *sockaddr)
+{
+	struct ibnbd_session *sess;
+
+	mutex_lock(&sess_lock);
+	sess = ibnbd_clt_find_sess(sockaddr);
+	if (sess) {
+		if (sess->state != SESS_STATE_READY ||
+		    !ibnbd_clt_get_sess(sess)) {
+			ERR_NP("Session is not connected or "
+			       "is being destroyed\n");
+			sess = ERR_PTR(-EIO);
+		}
+	} else {
+		sess = ibnbd_create_session(sockaddr);
+	}
+	mutex_unlock(&sess_lock);
+
+	return sess;
+}
+
+static ssize_t ibnbd_clt_map_device_show(struct kobject *kobj,
+					 struct kobj_attribute *attr,
+					 char *page)
+{
+	return scnprintf(page, PAGE_SIZE, "Usage: echo \"server=<address>"
+			 " device_path=<full path on remote side>"
+			 " [access_mode=<ro|rw|migration>]"
+			 " [input_mode=<mq|rq>]"
+			 " [io_mode=<fileio|blockio>]\" > %s\n\n"
+			 "address ::= [ ip:<ipv4> | ip:<ipv6> | gid:<gid> ]\n",
+			 attr->attr.name);
+}
+
+static int ibnbd_clt_get_path_name(struct ibnbd_dev *dev, char *buf,
+				   size_t len)
+{
+	int ret;
+	char pathname[NAME_MAX], *s;
+
+	strlcpy(pathname, dev->pathname, sizeof(pathname));
+	while ((s = strchr(pathname, '/')))
+		s[0] = '!';
+
+	ret = snprintf(buf, len, "%s", pathname);
+	if (ret >= len)
+		return -ENAMETOOLONG;
+
+	return 0;
+}
+
+static int ibnbd_clt_add_dev_symlink(struct ibnbd_dev *dev)
+{
+	struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
+	int ret;
+
+	ret = ibnbd_clt_get_path_name(dev, dev->blk_symlink_name,
+				      sizeof(dev->blk_symlink_name));
+	if (ret) {
+		ERR(dev, "Failed to get /sys/block symlink path, error: %d.\n",
+		    ret);
+		goto out_err;
+	}
+
+	ret = sysfs_create_link(ibnbd_devices_kobject, gd_kobj,
+				dev->blk_symlink_name);
+	if (ret) {
+		ERR(dev, "Creating /sys/block symlink failed, error: %d.\n",
+		    ret);
+		goto out_err;
+	}
+
+	return 0;
+
+out_err:
+	dev->blk_symlink_name[0] = '\0';
+	return ret;
+}
+
+static ssize_t ibnbd_clt_map_device_store(struct kobject *kobj,
+					  struct kobj_attribute *attr,
+					  const char *buf, size_t count)
+{
+	struct ibnbd_session *sess;
+	struct ibnbd_dev *dev;
+	int ret;
+	char pathname[NAME_MAX];
+	char server_addr[IBTRS_ADDRLEN];
+	enum ibnbd_access_mode access_mode = IBNBD_ACCESS_RW;
+	enum ibnbd_queue_mode queue_mode = BLK_MQ;
+	enum ibnbd_io_mode io_mode = IBNBD_AUTOIO;
+	struct sockaddr_storage sockaddr;
+
+	ret = ibnbd_clt_parse_map_options(buf, server_addr, pathname,
+					  &access_mode, &queue_mode,
+					  &io_mode);
+	if (ret)
+		return ret;
+
+	ret = ibnbd_clt_str_to_sockaddr(server_addr, &sockaddr);
+	if (ret) {
+		if (ret == -EPROTONOSUPPORT)
+			ERR_NP("Invalid address protocol provided: %s\n",
+			       server_addr);
+		else
+			ERR_NP("Converting address to binary format failed: "
+			       "%s\n", server_addr);
+		return -EINVAL;
+	}
+
+	if (ibnbd_clt_dev_is_mapped(pathname)) {
+		ERR_NP("map_device: failed, Device with same path '%s' is"
+		       " already mapped\n", pathname);
+		return -EEXIST;
+	}
+
+	INFO_NP("Mapping device %s from server %s,"
+	      " (access_mode: %s, input_mode: %s, io_mode: %s)\n",
+	      pathname, server_addr, ibnbd_access_mode_str(access_mode),
+	      ibnbd_queue_mode_str(queue_mode), ibnbd_io_mode_str(io_mode));
+
+	sess = ibnbd_clt_get_create_sess(&sockaddr);
+	if (IS_ERR(sess))
+		return PTR_ERR(sess);
+
+	dev = ibnbd_client_add_device(sess, pathname, access_mode, queue_mode,
+				      io_mode);
+	if (IS_ERR(dev)) {
+		ret = PTR_ERR(dev);
+		goto out_sess_put;
+	}
+
+	ret = ibnbd_clt_add_dev_kobj(dev);
+	if (ret) {
+		if (!WARN_ON(ibnbd_close_device(dev, true)))
+			wait_for_completion(dev->close_compl);
+		/* ibnbd_destroy_gen_disk() will put the reference that was
+		 * acquired by ibnbd_client_add_device()
+		 */
+		ibnbd_destroy_gen_disk(dev);
+		goto out_sess_put;
+	}
+
+	ret = ibnbd_clt_add_dev_symlink(dev);
+	if (ret)
+		goto out_close_dev;
+
+	ibnbd_clt_put_sess(sess);
+	return count;
+
+out_close_dev:
+	if (!WARN_ON(ibnbd_close_device(dev, true)))
+		wait_for_completion(dev->close_compl);
+	kobject_del(&dev->kobj);
+	kobject_put(&dev->kobj);
+out_sess_put:
+	ibnbd_clt_put_sess(sess);
+
+	return ret;
+}
+
+static struct kobj_attribute ibnbd_clt_map_device_attr =
+	__ATTR(map_device, 0644,
+	       ibnbd_clt_map_device_show, ibnbd_clt_map_device_store);
+
+static struct attribute *default_attrs[] = {
+	&ibnbd_clt_map_device_attr.attr,
+	NULL,
+};
+
+static struct attribute_group default_attr_group = {
+	.attrs = default_attrs,
+};
+
+int ibnbd_clt_create_sysfs_files(void)
+{
+	int err = 0;
+
+	ibnbd_kobject = kobject_create_and_add("ibnbd", kernel_kobj);
+	if (!ibnbd_kobject) {
+		err = -ENOMEM;
+		goto err1;
+	}
+
+	ibnbd_devices_kobject = kobject_create_and_add("devices",
+						       ibnbd_kobject);
+	if (!ibnbd_devices_kobject) {
+		err = -ENOMEM;
+		goto err2;
+	}
+
+	err = sysfs_create_group(ibnbd_kobject, &default_attr_group);
+	if (err)
+		goto err3;
+
+	return 0;
+
+err3:
+	kobject_put(ibnbd_devices_kobject);
+err2:
+	kobject_put(ibnbd_kobject);
+err1:
+	return err;
+}
+
+void ibnbd_clt_destroy_default_group(void)
+{
+	sysfs_remove_group(ibnbd_kobject, &default_attr_group);
+}
+
+void ibnbd_clt_destroy_sysfs_files(void)
+{
+	kobject_put(ibnbd_devices_kobject);
+	kobject_put(ibnbd_kobject);
+}
diff --git a/drivers/block/ibnbd_client/ibnbd_clt_sysfs.h b/drivers/block/ibnbd_client/ibnbd_clt_sysfs.h
new file mode 100644
index 0000000..34f6013
--- /dev/null
+++ b/drivers/block/ibnbd_client/ibnbd_clt_sysfs.h
@@ -0,0 +1,64 @@ 
+/*
+ * InfiniBand Network Block Driver
+ *
+ * Copyright (c) 2014 - 2017 ProfitBricks GmbH. All rights reserved.
+ * Authors: Fabian Holler < mail@fholler.de>
+ *          Jack Wang <jinpu.wang@profitbricks.com>
+ *   	    Kleber Souza <kleber.souza@profitbricks.com>
+ * 	    Danil Kipnis <danil.kipnis@profitbricks.com>
+ *   	    Roman Pen <roman.penyaev@profitbricks.com>
+ *          Milind Dumbare <Milind.dumbare@gmail.com>
+ *
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ *
+ */
+
+#ifndef _IBNBD_CLT_SYSFS_H
+#define _IBNBD_CLT_SYSFS_H
+
+#include "ibnbd_clt.h"
+
+int ibnbd_clt_create_sysfs_files(void);
+
+void ibnbd_clt_destroy_sysfs_files(void);
+void ibnbd_clt_destroy_default_group(void);
+void ibnbd_clt_schedule_dev_destroy(struct ibnbd_dev *dev);
+
+void ibnbd_clt_remove_dev_symlink(struct ibnbd_dev *dev);
+
+int ibnbd_clt_get_sess(struct ibnbd_session *sess);
+
+void ibnbd_clt_put_sess(struct ibnbd_session *sess);
+
+#endif