[PATCH 03/24] ibtrs: core: lib functions shared between client and server modules

[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: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Danil Kipnis <danil.kipnis@profitbricks.com>
Cc: Jack Wang <jinpu.wang@profitbricks.com>
---
 drivers/infiniband/ulp/ibtrs/ibtrs.c | 582 +++++++++++++++++++++++++++++++++++
 1 file changed, 582 insertions(+)

diff --git a/drivers/infiniband/ulp/ibtrs/ibtrs.c b/drivers/infiniband/ulp/ibtrs/ibtrs.c
new file mode 100644
index 000000000000..007380506959
--- /dev/null
+++ b/drivers/infiniband/ulp/ibtrs/ibtrs.c
@@ -0,0 +1,582 @@
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#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");
+
+static LIST_HEAD(device_list);
+static DEFINE_MUTEX(device_list_mutex);
+
+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, *bad_wr;
+	struct ib_sge list;
+
+	list.addr   = iu->dma_addr;
+	list.length = iu->size;
+	list.lkey   = sess->ib_dev->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, *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_iu_post_send(struct ibtrs_con *con, struct ibtrs_iu *iu, size_t size)
+{
+	struct ibtrs_sess *sess = con->sess;
+	struct ib_send_wr 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->ib_dev->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;
+
+	return ib_post_send(con->qp, &wr, &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 *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;
+
+	return ib_post_send(con->qp, &wr.wr, &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 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);
+
+	return ib_post_send(con->qp, &wr, &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 ibtrs_query_device(struct ibtrs_ib_dev *ib_dev)
+{
+	struct ib_udata uhw = {.outlen = 0, .inlen = 0};
+
+	memset(&ib_dev->attrs, 0, sizeof(ib_dev->attrs));
+
+	return ib_dev->dev->query_device(ib_dev->dev, &ib_dev->attrs, &uhw);
+}
+
+static int ibtrs_ib_dev_init(struct ibtrs_ib_dev *d, struct ib_device *dev)
+{
+	int err;
+
+	d->pd = ib_alloc_pd(dev, IB_PD_UNSAFE_GLOBAL_RKEY);
+	if (IS_ERR(d->pd))
+		return PTR_ERR(d->pd);
+	d->dev = dev;
+	d->lkey = d->pd->local_dma_lkey;
+	d->rkey = d->pd->unsafe_global_rkey;
+
+	err = ibtrs_query_device(d);
+	if (unlikely(err))
+		ib_dealloc_pd(d->pd);
+
+	return err;
+}
+
+static void ibtrs_ib_dev_destroy(struct ibtrs_ib_dev *d)
+{
+	if (d->pd) {
+		ib_dealloc_pd(d->pd);
+		d->pd = NULL;
+		d->dev = NULL;
+		d->lkey = 0;
+		d->rkey = 0;
+	}
+}
+
+struct ibtrs_ib_dev *ibtrs_ib_dev_find_get(struct rdma_cm_id *cm_id)
+{
+	struct ibtrs_ib_dev *dev;
+	int err;
+
+	mutex_lock(&device_list_mutex);
+	list_for_each_entry(dev, &device_list, entry) {
+		if (dev->dev->node_guid == cm_id->device->node_guid &&
+		    kref_get_unless_zero(&dev->ref))
+			goto out_unlock;
+	}
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (unlikely(!dev))
+		goto out_err;
+
+	kref_init(&dev->ref);
+	err = ibtrs_ib_dev_init(dev, cm_id->device);
+	if (unlikely(err))
+		goto out_free;
+	list_add(&dev->entry, &device_list);
+out_unlock:
+	mutex_unlock(&device_list_mutex);
+
+	return dev;
+
+out_free:
+	kfree(dev);
+out_err:
+	mutex_unlock(&device_list_mutex);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(ibtrs_ib_dev_find_get);
+
+static void ibtrs_ib_dev_free(struct kref *ref)
+{
+	struct ibtrs_ib_dev *dev;
+
+	dev = container_of(ref, struct ibtrs_ib_dev, ref);
+
+	mutex_lock(&device_list_mutex);
+	list_del(&dev->entry);
+	mutex_unlock(&device_list_mutex);
+	ibtrs_ib_dev_destroy(dev);
+	kfree(dev);
+}
+
+void ibtrs_ib_dev_put(struct ibtrs_ib_dev *dev)
+{
+	kref_put(&dev->ref, ibtrs_ib_dev_free);
+}
+EXPORT_SYMBOL_GPL(ibtrs_ib_dev_put);
+
+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 * 2 + 1,
+			 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_send_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 = 2;
+	init_attr.event_handler = qp_event_handler;
+	init_attr.qp_context = con;
+	init_attr.cap.max_send_sge = max_send_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->ib_dev->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);
+	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);
+	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_ipv4_to_sockaddr(const char *addr, size_t len,
+				      short port, struct sockaddr *dst)
+{
+	struct sockaddr_in *dst_sin = (struct sockaddr_in *)dst;
+	int ret;
+
+	ret = in4_pton(addr, len, (u8 *)&dst_sin->sin_addr.s_addr,
+		       '\0', NULL);
+	if (ret == 0)
+		return -EINVAL;
+
+	dst_sin->sin_family = AF_INET;
+	dst_sin->sin_port = htons(port);
+
+	return 0;
+}
+
+static int ibtrs_str_ipv6_to_sockaddr(const char *addr, size_t len,
+				      short port, struct sockaddr *dst)
+{
+	struct sockaddr_in6 *dst_sin6 = (struct sockaddr_in6 *)dst;
+	int ret;
+
+	ret = in6_pton(addr, len, dst_sin6->sin6_addr.s6_addr,
+		       '\0', NULL);
+	if (ret != 1)
+		return -EINVAL;
+
+	dst_sin6->sin6_family = AF_INET6;
+	dst_sin6->sin6_port = htons(port);
+
+	return 0;
+}
+
+static int ibtrs_str_gid_to_sockaddr(const char *addr, size_t len,
+				     short port, struct sockaddr *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 *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) {
+		if (ibtrs_str_ipv4_to_sockaddr(addr + 3, len - 3, port, dst))
+			return ibtrs_str_ipv6_to_sockaddr(addr + 3, len - 3,
+							  port, dst);
+		else
+			return 0;
+	}
+	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) {
+		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);
-- 
2.13.1