summaryrefslogtreecommitdiff
path: root/net/rds/ib_cm.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/rds/ib_cm.c')
-rw-r--r--net/rds/ib_cm.c838
1 files changed, 838 insertions, 0 deletions
diff --git a/net/rds/ib_cm.c b/net/rds/ib_cm.c
new file mode 100644
index 000000000..8a09ee7db
--- /dev/null
+++ b/net/rds/ib_cm.c
@@ -0,0 +1,838 @@
+/*
+ * Copyright (c) 2006 Oracle. 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/kernel.h>
+#include <linux/in.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/ratelimit.h>
+
+#include "rds.h"
+#include "ib.h"
+
+static char *rds_ib_event_type_strings[] = {
+#define RDS_IB_EVENT_STRING(foo) \
+ [IB_EVENT_##foo] = __stringify(IB_EVENT_##foo)
+ RDS_IB_EVENT_STRING(CQ_ERR),
+ RDS_IB_EVENT_STRING(QP_FATAL),
+ RDS_IB_EVENT_STRING(QP_REQ_ERR),
+ RDS_IB_EVENT_STRING(QP_ACCESS_ERR),
+ RDS_IB_EVENT_STRING(COMM_EST),
+ RDS_IB_EVENT_STRING(SQ_DRAINED),
+ RDS_IB_EVENT_STRING(PATH_MIG),
+ RDS_IB_EVENT_STRING(PATH_MIG_ERR),
+ RDS_IB_EVENT_STRING(DEVICE_FATAL),
+ RDS_IB_EVENT_STRING(PORT_ACTIVE),
+ RDS_IB_EVENT_STRING(PORT_ERR),
+ RDS_IB_EVENT_STRING(LID_CHANGE),
+ RDS_IB_EVENT_STRING(PKEY_CHANGE),
+ RDS_IB_EVENT_STRING(SM_CHANGE),
+ RDS_IB_EVENT_STRING(SRQ_ERR),
+ RDS_IB_EVENT_STRING(SRQ_LIMIT_REACHED),
+ RDS_IB_EVENT_STRING(QP_LAST_WQE_REACHED),
+ RDS_IB_EVENT_STRING(CLIENT_REREGISTER),
+#undef RDS_IB_EVENT_STRING
+};
+
+static char *rds_ib_event_str(enum ib_event_type type)
+{
+ return rds_str_array(rds_ib_event_type_strings,
+ ARRAY_SIZE(rds_ib_event_type_strings), type);
+};
+
+/*
+ * Set the selected protocol version
+ */
+static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
+{
+ conn->c_version = version;
+}
+
+/*
+ * Set up flow control
+ */
+static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
+{
+ struct rds_ib_connection *ic = conn->c_transport_data;
+
+ if (rds_ib_sysctl_flow_control && credits != 0) {
+ /* We're doing flow control */
+ ic->i_flowctl = 1;
+ rds_ib_send_add_credits(conn, credits);
+ } else {
+ ic->i_flowctl = 0;
+ }
+}
+
+/*
+ * Tune RNR behavior. Without flow control, we use a rather
+ * low timeout, but not the absolute minimum - this should
+ * be tunable.
+ *
+ * We already set the RNR retry count to 7 (which is the
+ * smallest infinite number :-) above.
+ * If flow control is off, we want to change this back to 0
+ * so that we learn quickly when our credit accounting is
+ * buggy.
+ *
+ * Caller passes in a qp_attr pointer - don't waste stack spacv
+ * by allocation this twice.
+ */
+static void
+rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
+{
+ int ret;
+
+ attr->min_rnr_timer = IB_RNR_TIMER_000_32;
+ ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
+ if (ret)
+ printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
+}
+
+/*
+ * Connection established.
+ * We get here for both outgoing and incoming connection.
+ */
+void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
+{
+ const struct rds_ib_connect_private *dp = NULL;
+ struct rds_ib_connection *ic = conn->c_transport_data;
+ struct ib_qp_attr qp_attr;
+ int err;
+
+ if (event->param.conn.private_data_len >= sizeof(*dp)) {
+ dp = event->param.conn.private_data;
+
+ /* make sure it isn't empty data */
+ if (dp->dp_protocol_major) {
+ rds_ib_set_protocol(conn,
+ RDS_PROTOCOL(dp->dp_protocol_major,
+ dp->dp_protocol_minor));
+ rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
+ }
+ }
+
+ if (conn->c_version < RDS_PROTOCOL(3,1)) {
+ printk(KERN_NOTICE "RDS/IB: Connection to %pI4 version %u.%u failed,"
+ " no longer supported\n",
+ &conn->c_faddr,
+ RDS_PROTOCOL_MAJOR(conn->c_version),
+ RDS_PROTOCOL_MINOR(conn->c_version));
+ rds_conn_destroy(conn);
+ return;
+ } else {
+ printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
+ &conn->c_faddr,
+ RDS_PROTOCOL_MAJOR(conn->c_version),
+ RDS_PROTOCOL_MINOR(conn->c_version),
+ ic->i_flowctl ? ", flow control" : "");
+ }
+
+ /*
+ * Init rings and fill recv. this needs to wait until protocol negotiation
+ * is complete, since ring layout is different from 3.0 to 3.1.
+ */
+ rds_ib_send_init_ring(ic);
+ rds_ib_recv_init_ring(ic);
+ /* Post receive buffers - as a side effect, this will update
+ * the posted credit count. */
+ rds_ib_recv_refill(conn, 1);
+
+ /* Tune RNR behavior */
+ rds_ib_tune_rnr(ic, &qp_attr);
+
+ qp_attr.qp_state = IB_QPS_RTS;
+ err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
+ if (err)
+ printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
+
+ /* update ib_device with this local ipaddr */
+ err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
+ if (err)
+ printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
+ err);
+
+ /* If the peer gave us the last packet it saw, process this as if
+ * we had received a regular ACK. */
+ if (dp) {
+ /* dp structure start is not guaranteed to be 8 bytes aligned.
+ * Since dp_ack_seq is 64-bit extended load operations can be
+ * used so go through get_unaligned to avoid unaligned errors.
+ */
+ __be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq);
+
+ if (dp_ack_seq)
+ rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq),
+ NULL);
+ }
+
+ rds_connect_complete(conn);
+}
+
+static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
+ struct rdma_conn_param *conn_param,
+ struct rds_ib_connect_private *dp,
+ u32 protocol_version,
+ u32 max_responder_resources,
+ u32 max_initiator_depth)
+{
+ struct rds_ib_connection *ic = conn->c_transport_data;
+ struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
+
+ memset(conn_param, 0, sizeof(struct rdma_conn_param));
+
+ conn_param->responder_resources =
+ min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
+ conn_param->initiator_depth =
+ min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
+ conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
+ conn_param->rnr_retry_count = 7;
+
+ if (dp) {
+ memset(dp, 0, sizeof(*dp));
+ dp->dp_saddr = conn->c_laddr;
+ dp->dp_daddr = conn->c_faddr;
+ dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
+ dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
+ dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
+ dp->dp_ack_seq = rds_ib_piggyb_ack(ic);
+
+ /* Advertise flow control */
+ if (ic->i_flowctl) {
+ unsigned int credits;
+
+ credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
+ dp->dp_credit = cpu_to_be32(credits);
+ atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
+ }
+
+ conn_param->private_data = dp;
+ conn_param->private_data_len = sizeof(*dp);
+ }
+}
+
+static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
+{
+ rdsdebug("event %u (%s) data %p\n",
+ event->event, rds_ib_event_str(event->event), data);
+}
+
+static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
+{
+ struct rds_connection *conn = data;
+ struct rds_ib_connection *ic = conn->c_transport_data;
+
+ rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
+ rds_ib_event_str(event->event));
+
+ switch (event->event) {
+ case IB_EVENT_COMM_EST:
+ rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
+ break;
+ default:
+ rdsdebug("Fatal QP Event %u (%s) "
+ "- connection %pI4->%pI4, reconnecting\n",
+ event->event, rds_ib_event_str(event->event),
+ &conn->c_laddr, &conn->c_faddr);
+ rds_conn_drop(conn);
+ break;
+ }
+}
+
+/*
+ * This needs to be very careful to not leave IS_ERR pointers around for
+ * cleanup to trip over.
+ */
+static int rds_ib_setup_qp(struct rds_connection *conn)
+{
+ struct rds_ib_connection *ic = conn->c_transport_data;
+ struct ib_device *dev = ic->i_cm_id->device;
+ struct ib_qp_init_attr attr;
+ struct rds_ib_device *rds_ibdev;
+ int ret;
+
+ /*
+ * It's normal to see a null device if an incoming connection races
+ * with device removal, so we don't print a warning.
+ */
+ rds_ibdev = rds_ib_get_client_data(dev);
+ if (!rds_ibdev)
+ return -EOPNOTSUPP;
+
+ /* add the conn now so that connection establishment has the dev */
+ rds_ib_add_conn(rds_ibdev, conn);
+
+ if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
+ rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
+ if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
+ rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
+
+ /* Protection domain and memory range */
+ ic->i_pd = rds_ibdev->pd;
+ ic->i_mr = rds_ibdev->mr;
+
+ ic->i_send_cq = ib_create_cq(dev, rds_ib_send_cq_comp_handler,
+ rds_ib_cq_event_handler, conn,
+ ic->i_send_ring.w_nr + 1, 0);
+ if (IS_ERR(ic->i_send_cq)) {
+ ret = PTR_ERR(ic->i_send_cq);
+ ic->i_send_cq = NULL;
+ rdsdebug("ib_create_cq send failed: %d\n", ret);
+ goto out;
+ }
+
+ ic->i_recv_cq = ib_create_cq(dev, rds_ib_recv_cq_comp_handler,
+ rds_ib_cq_event_handler, conn,
+ ic->i_recv_ring.w_nr, 0);
+ if (IS_ERR(ic->i_recv_cq)) {
+ ret = PTR_ERR(ic->i_recv_cq);
+ ic->i_recv_cq = NULL;
+ rdsdebug("ib_create_cq recv failed: %d\n", ret);
+ goto out;
+ }
+
+ ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
+ if (ret) {
+ rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
+ goto out;
+ }
+
+ ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
+ if (ret) {
+ rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
+ goto out;
+ }
+
+ /* XXX negotiate max send/recv with remote? */
+ memset(&attr, 0, sizeof(attr));
+ attr.event_handler = rds_ib_qp_event_handler;
+ attr.qp_context = conn;
+ /* + 1 to allow for the single ack message */
+ attr.cap.max_send_wr = ic->i_send_ring.w_nr + 1;
+ attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
+ attr.cap.max_send_sge = rds_ibdev->max_sge;
+ attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
+ attr.sq_sig_type = IB_SIGNAL_REQ_WR;
+ attr.qp_type = IB_QPT_RC;
+ attr.send_cq = ic->i_send_cq;
+ attr.recv_cq = ic->i_recv_cq;
+
+ /*
+ * XXX this can fail if max_*_wr is too large? Are we supposed
+ * to back off until we get a value that the hardware can support?
+ */
+ ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
+ if (ret) {
+ rdsdebug("rdma_create_qp failed: %d\n", ret);
+ goto out;
+ }
+
+ ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
+ ic->i_send_ring.w_nr *
+ sizeof(struct rds_header),
+ &ic->i_send_hdrs_dma, GFP_KERNEL);
+ if (!ic->i_send_hdrs) {
+ ret = -ENOMEM;
+ rdsdebug("ib_dma_alloc_coherent send failed\n");
+ goto out;
+ }
+
+ ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
+ ic->i_recv_ring.w_nr *
+ sizeof(struct rds_header),
+ &ic->i_recv_hdrs_dma, GFP_KERNEL);
+ if (!ic->i_recv_hdrs) {
+ ret = -ENOMEM;
+ rdsdebug("ib_dma_alloc_coherent recv failed\n");
+ goto out;
+ }
+
+ ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
+ &ic->i_ack_dma, GFP_KERNEL);
+ if (!ic->i_ack) {
+ ret = -ENOMEM;
+ rdsdebug("ib_dma_alloc_coherent ack failed\n");
+ goto out;
+ }
+
+ ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
+ ibdev_to_node(dev));
+ if (!ic->i_sends) {
+ ret = -ENOMEM;
+ rdsdebug("send allocation failed\n");
+ goto out;
+ }
+
+ ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
+ ibdev_to_node(dev));
+ if (!ic->i_recvs) {
+ ret = -ENOMEM;
+ rdsdebug("recv allocation failed\n");
+ goto out;
+ }
+
+ rds_ib_recv_init_ack(ic);
+
+ rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr,
+ ic->i_send_cq, ic->i_recv_cq);
+
+out:
+ rds_ib_dev_put(rds_ibdev);
+ return ret;
+}
+
+static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
+{
+ const struct rds_ib_connect_private *dp = event->param.conn.private_data;
+ u16 common;
+ u32 version = 0;
+
+ /*
+ * rdma_cm private data is odd - when there is any private data in the
+ * request, we will be given a pretty large buffer without telling us the
+ * original size. The only way to tell the difference is by looking at
+ * the contents, which are initialized to zero.
+ * If the protocol version fields aren't set, this is a connection attempt
+ * from an older version. This could could be 3.0 or 2.0 - we can't tell.
+ * We really should have changed this for OFED 1.3 :-(
+ */
+
+ /* Be paranoid. RDS always has privdata */
+ if (!event->param.conn.private_data_len) {
+ printk(KERN_NOTICE "RDS incoming connection has no private data, "
+ "rejecting\n");
+ return 0;
+ }
+
+ /* Even if len is crap *now* I still want to check it. -ASG */
+ if (event->param.conn.private_data_len < sizeof (*dp) ||
+ dp->dp_protocol_major == 0)
+ return RDS_PROTOCOL_3_0;
+
+ common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
+ if (dp->dp_protocol_major == 3 && common) {
+ version = RDS_PROTOCOL_3_0;
+ while ((common >>= 1) != 0)
+ version++;
+ } else
+ printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
+ &dp->dp_saddr,
+ dp->dp_protocol_major,
+ dp->dp_protocol_minor);
+ return version;
+}
+
+int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
+ struct rdma_cm_event *event)
+{
+ __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
+ __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
+ const struct rds_ib_connect_private *dp = event->param.conn.private_data;
+ struct rds_ib_connect_private dp_rep;
+ struct rds_connection *conn = NULL;
+ struct rds_ib_connection *ic = NULL;
+ struct rdma_conn_param conn_param;
+ u32 version;
+ int err = 1, destroy = 1;
+
+ /* Check whether the remote protocol version matches ours. */
+ version = rds_ib_protocol_compatible(event);
+ if (!version)
+ goto out;
+
+ rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
+ "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
+ RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
+ (unsigned long long)be64_to_cpu(lguid),
+ (unsigned long long)be64_to_cpu(fguid));
+
+ conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_ib_transport,
+ GFP_KERNEL);
+ if (IS_ERR(conn)) {
+ rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
+ conn = NULL;
+ goto out;
+ }
+
+ /*
+ * The connection request may occur while the
+ * previous connection exist, e.g. in case of failover.
+ * But as connections may be initiated simultaneously
+ * by both hosts, we have a random backoff mechanism -
+ * see the comment above rds_queue_reconnect()
+ */
+ mutex_lock(&conn->c_cm_lock);
+ if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
+ if (rds_conn_state(conn) == RDS_CONN_UP) {
+ rdsdebug("incoming connect while connecting\n");
+ rds_conn_drop(conn);
+ rds_ib_stats_inc(s_ib_listen_closed_stale);
+ } else
+ if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
+ /* Wait and see - our connect may still be succeeding */
+ rds_ib_stats_inc(s_ib_connect_raced);
+ }
+ goto out;
+ }
+
+ ic = conn->c_transport_data;
+
+ rds_ib_set_protocol(conn, version);
+ rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
+
+ /* If the peer gave us the last packet it saw, process this as if
+ * we had received a regular ACK. */
+ if (dp->dp_ack_seq)
+ rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
+
+ BUG_ON(cm_id->context);
+ BUG_ON(ic->i_cm_id);
+
+ ic->i_cm_id = cm_id;
+ cm_id->context = conn;
+
+ /* We got halfway through setting up the ib_connection, if we
+ * fail now, we have to take the long route out of this mess. */
+ destroy = 0;
+
+ err = rds_ib_setup_qp(conn);
+ if (err) {
+ rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
+ goto out;
+ }
+
+ rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
+ event->param.conn.responder_resources,
+ event->param.conn.initiator_depth);
+
+ /* rdma_accept() calls rdma_reject() internally if it fails */
+ err = rdma_accept(cm_id, &conn_param);
+ if (err)
+ rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
+
+out:
+ if (conn)
+ mutex_unlock(&conn->c_cm_lock);
+ if (err)
+ rdma_reject(cm_id, NULL, 0);
+ return destroy;
+}
+
+
+int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
+{
+ struct rds_connection *conn = cm_id->context;
+ struct rds_ib_connection *ic = conn->c_transport_data;
+ struct rdma_conn_param conn_param;
+ struct rds_ib_connect_private dp;
+ int ret;
+
+ /* If the peer doesn't do protocol negotiation, we must
+ * default to RDSv3.0 */
+ rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
+ ic->i_flowctl = rds_ib_sysctl_flow_control; /* advertise flow control */
+
+ ret = rds_ib_setup_qp(conn);
+ if (ret) {
+ rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
+ goto out;
+ }
+
+ rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
+ UINT_MAX, UINT_MAX);
+ ret = rdma_connect(cm_id, &conn_param);
+ if (ret)
+ rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
+
+out:
+ /* Beware - returning non-zero tells the rdma_cm to destroy
+ * the cm_id. We should certainly not do it as long as we still
+ * "own" the cm_id. */
+ if (ret) {
+ if (ic->i_cm_id == cm_id)
+ ret = 0;
+ }
+ return ret;
+}
+
+int rds_ib_conn_connect(struct rds_connection *conn)
+{
+ struct rds_ib_connection *ic = conn->c_transport_data;
+ struct sockaddr_in src, dest;
+ int ret;
+
+ /* XXX I wonder what affect the port space has */
+ /* delegate cm event handler to rdma_transport */
+ ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
+ RDMA_PS_TCP, IB_QPT_RC);
+ if (IS_ERR(ic->i_cm_id)) {
+ ret = PTR_ERR(ic->i_cm_id);
+ ic->i_cm_id = NULL;
+ rdsdebug("rdma_create_id() failed: %d\n", ret);
+ goto out;
+ }
+
+ rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
+
+ src.sin_family = AF_INET;
+ src.sin_addr.s_addr = (__force u32)conn->c_laddr;
+ src.sin_port = (__force u16)htons(0);
+
+ dest.sin_family = AF_INET;
+ dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
+ dest.sin_port = (__force u16)htons(RDS_PORT);
+
+ ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
+ (struct sockaddr *)&dest,
+ RDS_RDMA_RESOLVE_TIMEOUT_MS);
+ if (ret) {
+ rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
+ ret);
+ rdma_destroy_id(ic->i_cm_id);
+ ic->i_cm_id = NULL;
+ }
+
+out:
+ return ret;
+}
+
+/*
+ * This is so careful about only cleaning up resources that were built up
+ * so that it can be called at any point during startup. In fact it
+ * can be called multiple times for a given connection.
+ */
+void rds_ib_conn_shutdown(struct rds_connection *conn)
+{
+ struct rds_ib_connection *ic = conn->c_transport_data;
+ int err = 0;
+
+ rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
+ ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
+ ic->i_cm_id ? ic->i_cm_id->qp : NULL);
+
+ if (ic->i_cm_id) {
+ struct ib_device *dev = ic->i_cm_id->device;
+
+ rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
+ err = rdma_disconnect(ic->i_cm_id);
+ if (err) {
+ /* Actually this may happen quite frequently, when
+ * an outgoing connect raced with an incoming connect.
+ */
+ rdsdebug("failed to disconnect, cm: %p err %d\n",
+ ic->i_cm_id, err);
+ }
+
+ /*
+ * We want to wait for tx and rx completion to finish
+ * before we tear down the connection, but we have to be
+ * careful not to get stuck waiting on a send ring that
+ * only has unsignaled sends in it. We've shutdown new
+ * sends before getting here so by waiting for signaled
+ * sends to complete we're ensured that there will be no
+ * more tx processing.
+ */
+ wait_event(rds_ib_ring_empty_wait,
+ rds_ib_ring_empty(&ic->i_recv_ring) &&
+ (atomic_read(&ic->i_signaled_sends) == 0));
+ tasklet_kill(&ic->i_recv_tasklet);
+
+ if (ic->i_send_hdrs)
+ ib_dma_free_coherent(dev,
+ ic->i_send_ring.w_nr *
+ sizeof(struct rds_header),
+ ic->i_send_hdrs,
+ ic->i_send_hdrs_dma);
+
+ if (ic->i_recv_hdrs)
+ ib_dma_free_coherent(dev,
+ ic->i_recv_ring.w_nr *
+ sizeof(struct rds_header),
+ ic->i_recv_hdrs,
+ ic->i_recv_hdrs_dma);
+
+ if (ic->i_ack)
+ ib_dma_free_coherent(dev, sizeof(struct rds_header),
+ ic->i_ack, ic->i_ack_dma);
+
+ if (ic->i_sends)
+ rds_ib_send_clear_ring(ic);
+ if (ic->i_recvs)
+ rds_ib_recv_clear_ring(ic);
+
+ if (ic->i_cm_id->qp)
+ rdma_destroy_qp(ic->i_cm_id);
+ if (ic->i_send_cq)
+ ib_destroy_cq(ic->i_send_cq);
+ if (ic->i_recv_cq)
+ ib_destroy_cq(ic->i_recv_cq);
+ rdma_destroy_id(ic->i_cm_id);
+
+ /*
+ * Move connection back to the nodev list.
+ */
+ if (ic->rds_ibdev)
+ rds_ib_remove_conn(ic->rds_ibdev, conn);
+
+ ic->i_cm_id = NULL;
+ ic->i_pd = NULL;
+ ic->i_mr = NULL;
+ ic->i_send_cq = NULL;
+ ic->i_recv_cq = NULL;
+ ic->i_send_hdrs = NULL;
+ ic->i_recv_hdrs = NULL;
+ ic->i_ack = NULL;
+ }
+ BUG_ON(ic->rds_ibdev);
+
+ /* Clear pending transmit */
+ if (ic->i_data_op) {
+ struct rds_message *rm;
+
+ rm = container_of(ic->i_data_op, struct rds_message, data);
+ rds_message_put(rm);
+ ic->i_data_op = NULL;
+ }
+
+ /* Clear the ACK state */
+ clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
+#ifdef KERNEL_HAS_ATOMIC64
+ atomic64_set(&ic->i_ack_next, 0);
+#else
+ ic->i_ack_next = 0;
+#endif
+ ic->i_ack_recv = 0;
+
+ /* Clear flow control state */
+ ic->i_flowctl = 0;
+ atomic_set(&ic->i_credits, 0);
+
+ rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
+ rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
+
+ if (ic->i_ibinc) {
+ rds_inc_put(&ic->i_ibinc->ii_inc);
+ ic->i_ibinc = NULL;
+ }
+
+ vfree(ic->i_sends);
+ ic->i_sends = NULL;
+ vfree(ic->i_recvs);
+ ic->i_recvs = NULL;
+}
+
+int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
+{
+ struct rds_ib_connection *ic;
+ unsigned long flags;
+ int ret;
+
+ /* XXX too lazy? */
+ ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
+ if (!ic)
+ return -ENOMEM;
+
+ ret = rds_ib_recv_alloc_caches(ic);
+ if (ret) {
+ kfree(ic);
+ return ret;
+ }
+
+ INIT_LIST_HEAD(&ic->ib_node);
+ tasklet_init(&ic->i_recv_tasklet, rds_ib_recv_tasklet_fn,
+ (unsigned long) ic);
+ mutex_init(&ic->i_recv_mutex);
+#ifndef KERNEL_HAS_ATOMIC64
+ spin_lock_init(&ic->i_ack_lock);
+#endif
+ atomic_set(&ic->i_signaled_sends, 0);
+
+ /*
+ * rds_ib_conn_shutdown() waits for these to be emptied so they
+ * must be initialized before it can be called.
+ */
+ rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
+ rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
+
+ ic->conn = conn;
+ conn->c_transport_data = ic;
+
+ spin_lock_irqsave(&ib_nodev_conns_lock, flags);
+ list_add_tail(&ic->ib_node, &ib_nodev_conns);
+ spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
+
+
+ rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
+ return 0;
+}
+
+/*
+ * Free a connection. Connection must be shut down and not set for reconnect.
+ */
+void rds_ib_conn_free(void *arg)
+{
+ struct rds_ib_connection *ic = arg;
+ spinlock_t *lock_ptr;
+
+ rdsdebug("ic %p\n", ic);
+
+ /*
+ * Conn is either on a dev's list or on the nodev list.
+ * A race with shutdown() or connect() would cause problems
+ * (since rds_ibdev would change) but that should never happen.
+ */
+ lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
+
+ spin_lock_irq(lock_ptr);
+ list_del(&ic->ib_node);
+ spin_unlock_irq(lock_ptr);
+
+ rds_ib_recv_free_caches(ic);
+
+ kfree(ic);
+}
+
+
+/*
+ * An error occurred on the connection
+ */
+void
+__rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
+{
+ va_list ap;
+
+ rds_conn_drop(conn);
+
+ va_start(ap, fmt);
+ vprintk(fmt, ap);
+ va_end(ap);
+}