diff mbox series

[v4,04/25] ibtrs: core: lib functions shared between client and server modules

Message ID 20190620150337.7847-5-jinpuwang@gmail.com (mailing list archive)
State New, archived
Headers show
Series InfiniBand Transport (IBTRS) and Network Block Device (IBNBD) | expand

Commit Message

Jinpu Wang June 20, 2019, 3:03 p.m. UTC
From: Roman Pen <roman.penyaev@profitbricks.com>

This is a set of library functions existing as a ibtrs-core module,
used by client and server modules.

Mainly these functions wrap IB and RDMA calls and provide a bit higher
abstraction for implementing of IBTRS protocol on client or server
sides.

Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/infiniband/ulp/ibtrs/ibtrs.c | 610 +++++++++++++++++++++++++++
 1 file changed, 610 insertions(+)
 create mode 100644 drivers/infiniband/ulp/ibtrs/ibtrs.c

Comments

Bart Van Assche Sept. 23, 2019, 11:03 p.m. UTC | #1
On 6/20/19 8:03 AM, Jack Wang wrote:
> +static int ibtrs_str_gid_to_sockaddr(const char *addr, size_t len,
> +				     short port, struct sockaddr_storage *dst)
> +{
> +	struct sockaddr_ib *dst_ib = (struct sockaddr_ib *)dst;
> +	int ret;
> +
> +	/*
> +	 * We can use some of the I6 functions since GID is a valid
> +	 * IPv6 address format
> +	 */
> +	ret = in6_pton(addr, len, 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 | port);
> +	dst_ib->sib_sid_mask = cpu_to_be64(0xffffffffffffffffULL);
> +	dst_ib->sib_pkey = cpu_to_be16(0xffff);
> +
> +	return 0;
> +}
> +
> +/**
> + * ibtrs_str_to_sockaddr() - Convert ibtrs address string to sockaddr
> + * @addr	String representation of an addr (IPv4, IPv6 or IB GID):
> + *              - "ip:192.168.1.1"
> + *              - "ip:fe80::200:5aee:feaa:20a2"
> + *              - "gid:fe80::200:5aee:feaa:20a2"
> + * @len         String address length
> + * @port	Destination port
> + * @dst		Destination sockaddr structure
> + *
> + * Returns 0 if conversion successful. Non-zero on error.
> + */
> +static int ibtrs_str_to_sockaddr(const char *addr, size_t len,
> +				 short port, struct sockaddr_storage *dst)
> +{
> +	if (strncmp(addr, "gid:", 4) == 0) {
> +		return ibtrs_str_gid_to_sockaddr(addr + 4, len - 4, port, dst);
> +	} else if (strncmp(addr, "ip:", 3) == 0) {
> +		char port_str[8];
> +		char *cpy;
> +		int err;
> +
> +		snprintf(port_str, sizeof(port_str), "%u", port);
> +		cpy = kstrndup(addr + 3, len - 3, GFP_KERNEL);
> +		err = cpy ? inet_pton_with_scope(&init_net, AF_UNSPEC,
> +						 cpy, port_str, dst) : -ENOMEM;
> +		kfree(cpy);
> +
> +		return err;
> +	}
> +	return -EPROTONOSUPPORT;
> +}

A considerable amount of code is required to support the IB/CM. Does 
supporting the IB/CM add any value? If that code would be left out, 
would anything break? Is it really useful to support IB networks where 
no IP address has been assigned to each IB port?

Thanks,

Bart.
Jinpu Wang Sept. 27, 2019, 10:13 a.m. UTC | #2
On Tue, Sep 24, 2019 at 1:03 AM Bart Van Assche <bvanassche@acm.org> wrote:
>
> On 6/20/19 8:03 AM, Jack Wang wrote:
> > +static int ibtrs_str_gid_to_sockaddr(const char *addr, size_t len,
> > +                                  short port, struct sockaddr_storage *dst)
> > +{
> > +     struct sockaddr_ib *dst_ib = (struct sockaddr_ib *)dst;
> > +     int ret;
> > +
> > +     /*
> > +      * We can use some of the I6 functions since GID is a valid
> > +      * IPv6 address format
> > +      */
> > +     ret = in6_pton(addr, len, 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 | port);
> > +     dst_ib->sib_sid_mask = cpu_to_be64(0xffffffffffffffffULL);
> > +     dst_ib->sib_pkey = cpu_to_be16(0xffff);
> > +
> > +     return 0;
> > +}
> > +
> > +/**
> > + * ibtrs_str_to_sockaddr() - Convert ibtrs address string to sockaddr
> > + * @addr     String representation of an addr (IPv4, IPv6 or IB GID):
> > + *              - "ip:192.168.1.1"
> > + *              - "ip:fe80::200:5aee:feaa:20a2"
> > + *              - "gid:fe80::200:5aee:feaa:20a2"
> > + * @len         String address length
> > + * @port     Destination port
> > + * @dst              Destination sockaddr structure
> > + *
> > + * Returns 0 if conversion successful. Non-zero on error.
> > + */
> > +static int ibtrs_str_to_sockaddr(const char *addr, size_t len,
> > +                              short port, struct sockaddr_storage *dst)
> > +{
> > +     if (strncmp(addr, "gid:", 4) == 0) {
> > +             return ibtrs_str_gid_to_sockaddr(addr + 4, len - 4, port, dst);
> > +     } else if (strncmp(addr, "ip:", 3) == 0) {
> > +             char port_str[8];
> > +             char *cpy;
> > +             int err;
> > +
> > +             snprintf(port_str, sizeof(port_str), "%u", port);
> > +             cpy = kstrndup(addr + 3, len - 3, GFP_KERNEL);
> > +             err = cpy ? inet_pton_with_scope(&init_net, AF_UNSPEC,
> > +                                              cpy, port_str, dst) : -ENOMEM;
> > +             kfree(cpy);
> > +
> > +             return err;
> > +     }
> > +     return -EPROTONOSUPPORT;
> > +}
>
> A considerable amount of code is required to support the IB/CM. Does
> supporting the IB/CM add any value? If that code would be left out,
> would anything break? Is it really useful to support IB networks where
> no IP address has been assigned to each IB port?

We had quite some problems with ipoib in the past, especially neighbor
discovery, from time to time
we encountered some IP are not reachable from other hosts.

That's why we want to have AF_IB support, which doesn't reply on IPoIB.

Thanks,
Jinpu
diff mbox series

Patch

diff --git a/drivers/infiniband/ulp/ibtrs/ibtrs.c b/drivers/infiniband/ulp/ibtrs/ibtrs.c
new file mode 100644
index 000000000000..f6879daa5bb9
--- /dev/null
+++ b/drivers/infiniband/ulp/ibtrs/ibtrs.c
@@ -0,0 +1,610 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * InfiniBand Transport Layer
+ *
+ * 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 Penyaev <roman.penyaev@profitbricks.com>
+ *          Milind Dumbare <Milind.dumbare@gmail.com>
+ *
+ * Copyright (c) 2017 - 2018 ProfitBricks GmbH. All rights reserved.
+ * Authors: Danil Kipnis <danil.kipnis@profitbricks.com>
+ *          Roman Penyaev <roman.penyaev@profitbricks.com>
+ *
+ * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
+ * Authors: Roman Penyaev <roman.penyaev@profitbricks.com>
+ *          Jack Wang <jinpu.wang@cloud.ionos.com>
+ *          Danil Kipnis <danil.kipnis@cloud.ionos.com>
+ */
+
+#undef pr_fmt
+#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
+
+#include <linux/module.h>
+#include <linux/inet.h>
+
+#include "ibtrs-pri.h"
+#include "ibtrs-log.h"
+
+MODULE_AUTHOR("ibnbd@profitbricks.com");
+MODULE_DESCRIPTION("IBTRS Core");
+MODULE_VERSION(IBTRS_VER_STRING);
+MODULE_LICENSE("GPL");
+
+struct ibtrs_iu *ibtrs_iu_alloc(u32 tag, size_t size, gfp_t gfp_mask,
+				struct ib_device *dma_dev,
+				enum dma_data_direction direction,
+				void (*done)(struct ib_cq *cq,
+					     struct ib_wc *wc))
+{
+	struct ibtrs_iu *iu;
+
+	iu = kmalloc(sizeof(*iu), gfp_mask);
+	if (unlikely(!iu))
+		return NULL;
+
+	iu->buf = kzalloc(size, gfp_mask);
+	if (unlikely(!iu->buf))
+		goto err1;
+
+	iu->dma_addr = ib_dma_map_single(dma_dev, iu->buf, size, direction);
+	if (unlikely(ib_dma_mapping_error(dma_dev, iu->dma_addr)))
+		goto err2;
+
+	iu->cqe.done  = done;
+	iu->size      = size;
+	iu->direction = direction;
+	iu->tag       = tag;
+
+	return iu;
+
+err2:
+	kfree(iu->buf);
+err1:
+	kfree(iu);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(ibtrs_iu_alloc);
+
+void ibtrs_iu_free(struct ibtrs_iu *iu, enum dma_data_direction dir,
+		   struct ib_device *ibdev)
+{
+	if (!iu)
+		return;
+
+	ib_dma_unmap_single(ibdev, iu->dma_addr, iu->size, dir);
+	kfree(iu->buf);
+	kfree(iu);
+}
+EXPORT_SYMBOL_GPL(ibtrs_iu_free);
+
+int ibtrs_iu_post_recv(struct ibtrs_con *con, struct ibtrs_iu *iu)
+{
+	struct ibtrs_sess *sess = con->sess;
+	struct ib_recv_wr wr;
+	const struct ib_recv_wr *bad_wr;
+	struct ib_sge list;
+
+	list.addr   = iu->dma_addr;
+	list.length = iu->size;
+	list.lkey   = sess->dev->ib_pd->local_dma_lkey;
+
+	if (WARN_ON(list.length == 0)) {
+		ibtrs_wrn(con, "Posting receive work request failed,"
+			  " sg list is empty\n");
+		return -EINVAL;
+	}
+
+	wr.next    = NULL;
+	wr.wr_cqe  = &iu->cqe;
+	wr.sg_list = &list;
+	wr.num_sge = 1;
+
+	return ib_post_recv(con->qp, &wr, &bad_wr);
+}
+EXPORT_SYMBOL_GPL(ibtrs_iu_post_recv);
+
+int ibtrs_post_recv_empty(struct ibtrs_con *con, struct ib_cqe *cqe)
+{
+	struct ib_recv_wr wr;
+	const struct ib_recv_wr *bad_wr;
+
+	wr.next    = NULL;
+	wr.wr_cqe  = cqe;
+	wr.sg_list = NULL;
+	wr.num_sge = 0;
+
+	return ib_post_recv(con->qp, &wr, &bad_wr);
+}
+EXPORT_SYMBOL_GPL(ibtrs_post_recv_empty);
+
+int ibtrs_post_recv_empty_x2(struct ibtrs_con *con, struct ib_cqe *cqe)
+{
+	struct ib_recv_wr wr_arr[2], *wr;
+	const struct ib_recv_wr *bad_wr;
+	int i;
+
+	memset(wr_arr, 0, sizeof(wr_arr));
+	for (i = 0; i < ARRAY_SIZE(wr_arr); i++) {
+		wr = &wr_arr[i];
+		wr->wr_cqe  = cqe;
+		if (i)
+			/* Chain backwards */
+			wr->next = &wr_arr[i - 1];
+	}
+
+	return ib_post_recv(con->qp, wr, &bad_wr);
+}
+EXPORT_SYMBOL_GPL(ibtrs_post_recv_empty_x2);
+
+int ibtrs_iu_post_send(struct ibtrs_con *con, struct ibtrs_iu *iu, size_t size,
+		       struct ib_send_wr *head)
+{
+	struct ibtrs_sess *sess = con->sess;
+	struct ib_send_wr wr;
+	const struct ib_send_wr *bad_wr;
+	struct ib_sge list;
+
+	if ((WARN_ON(size == 0)))
+		return -EINVAL;
+
+	list.addr   = iu->dma_addr;
+	list.length = size;
+	list.lkey   = sess->dev->ib_pd->local_dma_lkey;
+
+	memset(&wr, 0, sizeof(wr));
+	wr.next       = NULL;
+	wr.wr_cqe     = &iu->cqe;
+	wr.sg_list    = &list;
+	wr.num_sge    = 1;
+	wr.opcode     = IB_WR_SEND;
+	wr.send_flags = IB_SEND_SIGNALED;
+
+	if (head) {
+		struct ib_send_wr *tail = head;
+
+		while (tail->next)
+			tail = tail->next;
+		tail->next = &wr;
+	} else {
+		head = &wr;
+	}
+
+	return ib_post_send(con->qp, head, &bad_wr);
+}
+EXPORT_SYMBOL_GPL(ibtrs_iu_post_send);
+
+int ibtrs_iu_post_rdma_write_imm(struct ibtrs_con *con, struct ibtrs_iu *iu,
+				 struct ib_sge *sge, unsigned int num_sge,
+				 u32 rkey, u64 rdma_addr, u32 imm_data,
+				 enum ib_send_flags flags,
+				 struct ib_send_wr *head)
+{
+	const struct ib_send_wr *bad_wr;
+	struct ib_rdma_wr wr;
+	int i;
+
+	wr.wr.next	  = NULL;
+	wr.wr.wr_cqe	  = &iu->cqe;
+	wr.wr.sg_list	  = sge;
+	wr.wr.num_sge	  = num_sge;
+	wr.rkey		  = rkey;
+	wr.remote_addr	  = rdma_addr;
+	wr.wr.opcode	  = IB_WR_RDMA_WRITE_WITH_IMM;
+	wr.wr.ex.imm_data = cpu_to_be32(imm_data);
+	wr.wr.send_flags  = flags;
+
+	/*
+	 * If one of the sges has 0 size, the operation will fail with an
+	 * length error
+	 */
+	for (i = 0; i < num_sge; i++)
+		if (WARN_ON(sge[i].length == 0))
+			return -EINVAL;
+
+	if (head) {
+		struct ib_send_wr *tail = head;
+
+		while (tail->next)
+			tail = tail->next;
+		tail->next = &wr.wr;
+	} else {
+		head = &wr.wr;
+	}
+
+	return ib_post_send(con->qp, head, &bad_wr);
+}
+EXPORT_SYMBOL_GPL(ibtrs_iu_post_rdma_write_imm);
+
+int ibtrs_post_rdma_write_imm_empty(struct ibtrs_con *con, struct ib_cqe *cqe,
+				    u32 imm_data, enum ib_send_flags flags,
+				    struct ib_send_wr *head)
+{
+	struct ib_send_wr wr;
+	const struct ib_send_wr *bad_wr;
+
+	memset(&wr, 0, sizeof(wr));
+	wr.wr_cqe	= cqe;
+	wr.send_flags	= flags;
+	wr.opcode	= IB_WR_RDMA_WRITE_WITH_IMM;
+	wr.ex.imm_data	= cpu_to_be32(imm_data);
+
+	if (head) {
+		struct ib_send_wr *tail = head;
+
+		while (tail->next)
+			tail = tail->next;
+		tail->next = &wr;
+	} else {
+		head = &wr;
+	}
+
+	return ib_post_send(con->qp, head, &bad_wr);
+}
+EXPORT_SYMBOL_GPL(ibtrs_post_rdma_write_imm_empty);
+
+static void qp_event_handler(struct ib_event *ev, void *ctx)
+{
+	struct ibtrs_con *con = ctx;
+
+	switch (ev->event) {
+	case IB_EVENT_COMM_EST:
+		ibtrs_info(con, "QP event %s (%d) received\n",
+			   ib_event_msg(ev->event), ev->event);
+		rdma_notify(con->cm_id, IB_EVENT_COMM_EST);
+		break;
+	default:
+		ibtrs_info(con, "Unhandled QP event %s (%d) received\n",
+			   ib_event_msg(ev->event), ev->event);
+		break;
+	}
+}
+
+static int create_cq(struct ibtrs_con *con, int cq_vector, u16 cq_size,
+		     enum ib_poll_context poll_ctx)
+{
+	struct rdma_cm_id *cm_id = con->cm_id;
+	struct ib_cq *cq;
+
+	cq = ib_alloc_cq(cm_id->device, con, cq_size,
+			 cq_vector, poll_ctx);
+	if (unlikely(IS_ERR(cq))) {
+		ibtrs_err(con, "Creating completion queue failed, errno: %ld\n",
+			  PTR_ERR(cq));
+		return PTR_ERR(cq);
+	}
+	con->cq = cq;
+
+	return 0;
+}
+
+static int create_qp(struct ibtrs_con *con, struct ib_pd *pd,
+		     u16 wr_queue_size, u32 max_sge)
+{
+	struct ib_qp_init_attr init_attr = {NULL};
+	struct rdma_cm_id *cm_id = con->cm_id;
+	int ret;
+
+	init_attr.cap.max_send_wr = wr_queue_size;
+	init_attr.cap.max_recv_wr = wr_queue_size;
+	init_attr.cap.max_recv_sge = 1;
+	init_attr.event_handler = qp_event_handler;
+	init_attr.qp_context = con;
+#undef max_send_sge
+	init_attr.cap.max_send_sge = max_sge;
+
+	init_attr.qp_type = IB_QPT_RC;
+	init_attr.send_cq = con->cq;
+	init_attr.recv_cq = con->cq;
+	init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
+
+	ret = rdma_create_qp(cm_id, pd, &init_attr);
+	if (unlikely(ret)) {
+		ibtrs_err(con, "Creating QP failed, err: %d\n", ret);
+		return ret;
+	}
+	con->qp = cm_id->qp;
+
+	return ret;
+}
+
+int ibtrs_cq_qp_create(struct ibtrs_sess *sess, struct ibtrs_con *con,
+		       u32 max_send_sge, int cq_vector, u16 cq_size,
+		       u16 wr_queue_size, enum ib_poll_context poll_ctx)
+{
+	int err;
+
+	err = create_cq(con, cq_vector, cq_size, poll_ctx);
+	if (unlikely(err))
+		return err;
+
+	err = create_qp(con, sess->dev->ib_pd, wr_queue_size, max_send_sge);
+	if (unlikely(err)) {
+		ib_free_cq(con->cq);
+		con->cq = NULL;
+		return err;
+	}
+	con->sess = sess;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ibtrs_cq_qp_create);
+
+void ibtrs_cq_qp_destroy(struct ibtrs_con *con)
+{
+	if (con->qp) {
+		rdma_destroy_qp(con->cm_id);
+		con->qp = NULL;
+	}
+	if (con->cq) {
+		ib_free_cq(con->cq);
+		con->cq = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(ibtrs_cq_qp_destroy);
+
+static void schedule_hb(struct ibtrs_sess *sess)
+{
+	queue_delayed_work(sess->hb_wq, &sess->hb_dwork,
+			   msecs_to_jiffies(sess->hb_interval_ms));
+}
+
+void ibtrs_send_hb_ack(struct ibtrs_sess *sess)
+{
+	struct ibtrs_con *usr_con = sess->con[0];
+	u32 imm;
+	int err;
+
+	imm = ibtrs_to_imm(IBTRS_HB_ACK_IMM, 0);
+	err = ibtrs_post_rdma_write_imm_empty(usr_con, sess->hb_cqe, imm,
+					      IB_SEND_SIGNALED, NULL);
+	if (unlikely(err)) {
+		sess->hb_err_handler(usr_con, err);
+		return;
+	}
+}
+EXPORT_SYMBOL_GPL(ibtrs_send_hb_ack);
+
+static void hb_work(struct work_struct *work)
+{
+	struct ibtrs_con *usr_con;
+	struct ibtrs_sess *sess;
+	u32 imm;
+	int err;
+
+	sess = container_of(to_delayed_work(work), typeof(*sess), hb_dwork);
+	usr_con = sess->con[0];
+
+	if (sess->hb_missed_cnt > sess->hb_missed_max) {
+		sess->hb_err_handler(usr_con, -ETIMEDOUT);
+		return;
+	}
+	if (sess->hb_missed_cnt++) {
+		/* Reschedule work without sending hb */
+		schedule_hb(sess);
+		return;
+	}
+	imm = ibtrs_to_imm(IBTRS_HB_MSG_IMM, 0);
+	err = ibtrs_post_rdma_write_imm_empty(usr_con, sess->hb_cqe, imm,
+					      IB_SEND_SIGNALED, NULL);
+	if (unlikely(err)) {
+		sess->hb_err_handler(usr_con, err);
+		return;
+	}
+
+	schedule_hb(sess);
+}
+
+void ibtrs_init_hb(struct ibtrs_sess *sess, struct ib_cqe *cqe,
+		   unsigned int interval_ms, unsigned int missed_max,
+		   ibtrs_hb_handler_t *err_handler,
+		   struct workqueue_struct *wq)
+{
+	sess->hb_cqe = cqe;
+	sess->hb_interval_ms = interval_ms;
+	sess->hb_err_handler = err_handler;
+	sess->hb_wq = wq;
+	sess->hb_missed_max = missed_max;
+	sess->hb_missed_cnt = 0;
+	INIT_DELAYED_WORK(&sess->hb_dwork, hb_work);
+}
+EXPORT_SYMBOL_GPL(ibtrs_init_hb);
+
+void ibtrs_start_hb(struct ibtrs_sess *sess)
+{
+	schedule_hb(sess);
+}
+EXPORT_SYMBOL_GPL(ibtrs_start_hb);
+
+void ibtrs_stop_hb(struct ibtrs_sess *sess)
+{
+	cancel_delayed_work_sync(&sess->hb_dwork);
+	sess->hb_missed_cnt = 0;
+	sess->hb_missed_max = 0;
+}
+EXPORT_SYMBOL_GPL(ibtrs_stop_hb);
+
+static int ibtrs_str_gid_to_sockaddr(const char *addr, size_t len,
+				     short port, struct sockaddr_storage *dst)
+{
+	struct sockaddr_ib *dst_ib = (struct sockaddr_ib *)dst;
+	int ret;
+
+	/*
+	 * We can use some of the I6 functions since GID is a valid
+	 * IPv6 address format
+	 */
+	ret = in6_pton(addr, len, 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 | port);
+	dst_ib->sib_sid_mask = cpu_to_be64(0xffffffffffffffffULL);
+	dst_ib->sib_pkey = cpu_to_be16(0xffff);
+
+	return 0;
+}
+
+/**
+ * ibtrs_str_to_sockaddr() - Convert ibtrs address string to sockaddr
+ * @addr	String representation of an addr (IPv4, IPv6 or IB GID):
+ *              - "ip:192.168.1.1"
+ *              - "ip:fe80::200:5aee:feaa:20a2"
+ *              - "gid:fe80::200:5aee:feaa:20a2"
+ * @len         String address length
+ * @port	Destination port
+ * @dst		Destination sockaddr structure
+ *
+ * Returns 0 if conversion successful. Non-zero on error.
+ */
+static int ibtrs_str_to_sockaddr(const char *addr, size_t len,
+				 short port, struct sockaddr_storage *dst)
+{
+	if (strncmp(addr, "gid:", 4) == 0) {
+		return ibtrs_str_gid_to_sockaddr(addr + 4, len - 4, port, dst);
+	} else if (strncmp(addr, "ip:", 3) == 0) {
+		char port_str[8];
+		char *cpy;
+		int err;
+
+		snprintf(port_str, sizeof(port_str), "%u", port);
+		cpy = kstrndup(addr + 3, len - 3, GFP_KERNEL);
+		err = cpy ? inet_pton_with_scope(&init_net, AF_UNSPEC,
+						 cpy, port_str, dst) : -ENOMEM;
+		kfree(cpy);
+
+		return err;
+	}
+	return -EPROTONOSUPPORT;
+}
+
+int ibtrs_addr_to_sockaddr(const char *str, size_t len, short port,
+			   struct ibtrs_addr *addr)
+{
+	const char *d;
+	int ret;
+
+	d = strchr(str, ',');
+	if (!d)
+		d = strchr(str, '@');
+	if (d) {
+		if (ibtrs_str_to_sockaddr(str, d - str, 0, addr->src))
+			return -EINVAL;
+		d += 1;
+		len -= d - str;
+		str  = d;
+
+	} else {
+		addr->src = NULL;
+	}
+	ret = ibtrs_str_to_sockaddr(str, len, port, addr->dst);
+
+	return ret;
+}
+EXPORT_SYMBOL(ibtrs_addr_to_sockaddr);
+
+void ibtrs_ib_dev_pool_init(enum ib_pd_flags pd_flags,
+			    struct ibtrs_ib_dev_pool *pool)
+{
+	WARN_ON(pool->ops && (!pool->ops->alloc ^ !pool->ops->free));
+	INIT_LIST_HEAD(&pool->list);
+	mutex_init(&pool->mutex);
+	pool->pd_flags = pd_flags;
+}
+EXPORT_SYMBOL(ibtrs_ib_dev_pool_init);
+
+void ibtrs_ib_dev_pool_deinit(struct ibtrs_ib_dev_pool *pool)
+{
+	WARN_ON(!list_empty(&pool->list));
+}
+EXPORT_SYMBOL(ibtrs_ib_dev_pool_deinit);
+
+static void dev_free(struct kref *ref)
+{
+	struct ibtrs_ib_dev_pool *pool;
+	struct ibtrs_ib_dev *dev;
+
+	dev = container_of(ref, typeof(*dev), ref);
+	pool = dev->pool;
+
+	mutex_lock(&pool->mutex);
+	list_del(&dev->entry);
+	mutex_unlock(&pool->mutex);
+
+	if (pool->ops && pool->ops->deinit)
+		pool->ops->deinit(dev);
+
+	ib_dealloc_pd(dev->ib_pd);
+
+	if (pool->ops && pool->ops->free)
+		pool->ops->free(dev);
+	else
+		kfree(dev);
+}
+
+int ibtrs_ib_dev_put(struct ibtrs_ib_dev *dev)
+{
+	return kref_put(&dev->ref, dev_free);
+}
+EXPORT_SYMBOL(ibtrs_ib_dev_put);
+
+static int ibtrs_ib_dev_get(struct ibtrs_ib_dev *dev)
+{
+	return kref_get_unless_zero(&dev->ref);
+}
+
+struct ibtrs_ib_dev *
+ibtrs_ib_dev_find_or_add(struct ib_device *ib_dev,
+			 struct ibtrs_ib_dev_pool *pool)
+{
+	struct ibtrs_ib_dev *dev;
+
+	mutex_lock(&pool->mutex);
+	list_for_each_entry(dev, &pool->list, entry) {
+		if (dev->ib_dev->node_guid == ib_dev->node_guid &&
+		    ibtrs_ib_dev_get(dev))
+			goto out_unlock;
+	}
+	if (pool->ops && pool->ops->alloc)
+		dev = pool->ops->alloc();
+	else
+		dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (unlikely(IS_ERR_OR_NULL(dev)))
+		goto out_err;
+
+	kref_init(&dev->ref);
+	dev->pool = pool;
+	dev->ib_dev = ib_dev;
+	dev->ib_pd = ib_alloc_pd(ib_dev, pool->pd_flags);
+	if (unlikely(IS_ERR(dev->ib_pd)))
+		goto out_free_dev;
+
+	if (pool->ops && pool->ops->init && pool->ops->init(dev))
+		goto out_free_pd;
+
+	list_add(&dev->entry, &pool->list);
+out_unlock:
+	mutex_unlock(&pool->mutex);
+	return dev;
+
+out_free_pd:
+	ib_dealloc_pd(dev->ib_pd);
+out_free_dev:
+	if (pool->ops && pool->ops->free)
+		pool->ops->free(dev);
+	else
+		kfree(dev);
+out_err:
+	mutex_unlock(&pool->mutex);
+	return NULL;
+}
+EXPORT_SYMBOL(ibtrs_ib_dev_find_or_add);