--- /dev/null
+/*
+ * 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/if.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/if_arp.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include "rds.h"
+#include "ib.h"
+
+static unsigned int fmr_pool_size = RDS_FMR_POOL_SIZE;
+unsigned int fmr_message_size = RDS_FMR_SIZE + 1; /* +1 allows for unaligned MRs */
+unsigned int rds_ib_retry_count = RDS_IB_DEFAULT_RETRY_COUNT;
+
+module_param(fmr_pool_size, int, 0444);
+MODULE_PARM_DESC(fmr_pool_size, " Max number of fmr per HCA");
+module_param(fmr_message_size, int, 0444);
+MODULE_PARM_DESC(fmr_message_size, " Max size of a RDMA transfer");
+module_param(rds_ib_retry_count, int, 0444);
+MODULE_PARM_DESC(rds_ib_retry_count, " Number of hw retries before reporting an error");
+
+/*
+ * we have a clumsy combination of RCU and a rwsem protecting this list
+ * because it is used both in the get_mr fast path and while blocking in
+ * the FMR flushing path.
+ */
+DECLARE_RWSEM(rds_ib_devices_lock);
+struct list_head rds_ib_devices;
+
+/* NOTE: if also grabbing ibdev lock, grab this first */
+DEFINE_SPINLOCK(ib_nodev_conns_lock);
+LIST_HEAD(ib_nodev_conns);
+
+static void rds_ib_nodev_connect(void)
+{
+ struct rds_ib_connection *ic;
+
+ spin_lock(&ib_nodev_conns_lock);
+ list_for_each_entry(ic, &ib_nodev_conns, ib_node)
+ rds_conn_connect_if_down(ic->conn);
+ spin_unlock(&ib_nodev_conns_lock);
+}
+
+static void rds_ib_dev_shutdown(struct rds_ib_device *rds_ibdev)
+{
+ struct rds_ib_connection *ic;
+ unsigned long flags;
+
+ spin_lock_irqsave(&rds_ibdev->spinlock, flags);
+ list_for_each_entry(ic, &rds_ibdev->conn_list, ib_node)
+ rds_conn_drop(ic->conn);
+ spin_unlock_irqrestore(&rds_ibdev->spinlock, flags);
+}
+
+/*
+ * rds_ib_destroy_mr_pool() blocks on a few things and mrs drop references
+ * from interrupt context so we push freing off into a work struct in krdsd.
+ */
+static void rds_ib_dev_free(struct work_struct *work)
+{
+ struct rds_ib_ipaddr *i_ipaddr, *i_next;
+ struct rds_ib_device *rds_ibdev = container_of(work,
+ struct rds_ib_device, free_work);
+
+ if (rds_ibdev->mr_pool)
+ rds_ib_destroy_mr_pool(rds_ibdev->mr_pool);
+ if (rds_ibdev->mr)
+ ib_dereg_mr(rds_ibdev->mr);
+ if (rds_ibdev->pd)
+ ib_dealloc_pd(rds_ibdev->pd);
+
+ list_for_each_entry_safe(i_ipaddr, i_next, &rds_ibdev->ipaddr_list, list) {
+ list_del(&i_ipaddr->list);
+ kfree(i_ipaddr);
+ }
+
+ kfree(rds_ibdev);
+}
+
+void rds_ib_dev_put(struct rds_ib_device *rds_ibdev)
+{
+ BUG_ON(atomic_read(&rds_ibdev->refcount) <= 0);
+ if (atomic_dec_and_test(&rds_ibdev->refcount))
+ queue_work(rds_wq, &rds_ibdev->free_work);
+}
+
+static void rds_ib_add_one(struct ib_device *device)
+{
+ struct rds_ib_device *rds_ibdev;
+ struct ib_device_attr *dev_attr;
+
+ /* Only handle IB (no iWARP) devices */
+ if (device->node_type != RDMA_NODE_IB_CA)
+ return;
+
+ dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
+ if (!dev_attr)
+ return;
+
+ if (ib_query_device(device, dev_attr)) {
+ rdsdebug("Query device failed for %s\n", device->name);
+ goto free_attr;
+ }
+
+ rds_ibdev = kzalloc_node(sizeof(struct rds_ib_device), GFP_KERNEL,
+ ibdev_to_node(device));
+ if (!rds_ibdev)
+ goto free_attr;
+
+ spin_lock_init(&rds_ibdev->spinlock);
+ atomic_set(&rds_ibdev->refcount, 1);
+ INIT_WORK(&rds_ibdev->free_work, rds_ib_dev_free);
+
+ rds_ibdev->max_wrs = dev_attr->max_qp_wr;
+ rds_ibdev->max_sge = min(dev_attr->max_sge, RDS_IB_MAX_SGE);
+
+ rds_ibdev->fmr_max_remaps = dev_attr->max_map_per_fmr?: 32;
+ rds_ibdev->max_fmrs = dev_attr->max_fmr ?
+ min_t(unsigned int, dev_attr->max_fmr, fmr_pool_size) :
+ fmr_pool_size;
+
+ rds_ibdev->max_initiator_depth = dev_attr->max_qp_init_rd_atom;
+ rds_ibdev->max_responder_resources = dev_attr->max_qp_rd_atom;
+
+ rds_ibdev->dev = device;
+ rds_ibdev->pd = ib_alloc_pd(device);
+ if (IS_ERR(rds_ibdev->pd)) {
+ rds_ibdev->pd = NULL;
+ goto put_dev;
+ }
+
+ rds_ibdev->mr = ib_get_dma_mr(rds_ibdev->pd, IB_ACCESS_LOCAL_WRITE);
+ if (IS_ERR(rds_ibdev->mr)) {
+ rds_ibdev->mr = NULL;
+ goto put_dev;
+ }
+
+ rds_ibdev->mr_pool = rds_ib_create_mr_pool(rds_ibdev);
+ if (IS_ERR(rds_ibdev->mr_pool)) {
+ rds_ibdev->mr_pool = NULL;
+ goto put_dev;
+ }
+
+ INIT_LIST_HEAD(&rds_ibdev->ipaddr_list);
+ INIT_LIST_HEAD(&rds_ibdev->conn_list);
+
+ down_write(&rds_ib_devices_lock);
+ list_add_tail_rcu(&rds_ibdev->list, &rds_ib_devices);
+ up_write(&rds_ib_devices_lock);
+ atomic_inc(&rds_ibdev->refcount);
+
+ ib_set_client_data(device, &rds_ib_client, rds_ibdev);
+ atomic_inc(&rds_ibdev->refcount);
+
+ rds_ib_nodev_connect();
+
+put_dev:
+ rds_ib_dev_put(rds_ibdev);
+free_attr:
+ kfree(dev_attr);
+}
+
+/*
+ * New connections use this to find the device to associate with the
+ * connection. It's not in the fast path so we're not concerned about the
+ * performance of the IB call. (As of this writing, it uses an interrupt
+ * blocking spinlock to serialize walking a per-device list of all registered
+ * clients.)
+ *
+ * RCU is used to handle incoming connections racing with device teardown.
+ * Rather than use a lock to serialize removal from the client_data and
+ * getting a new reference, we use an RCU grace period. The destruction
+ * path removes the device from client_data and then waits for all RCU
+ * readers to finish.
+ *
+ * A new connection can get NULL from this if its arriving on a
+ * device that is in the process of being removed.
+ */
+struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device)
+{
+ struct rds_ib_device *rds_ibdev;
+
+ rcu_read_lock();
+ rds_ibdev = ib_get_client_data(device, &rds_ib_client);
+ if (rds_ibdev)
+ atomic_inc(&rds_ibdev->refcount);
+ rcu_read_unlock();
+ return rds_ibdev;
+}
+
+/*
+ * The IB stack is letting us know that a device is going away. This can
+ * happen if the underlying HCA driver is removed or if PCI hotplug is removing
+ * the pci function, for example.
+ *
+ * This can be called at any time and can be racing with any other RDS path.
+ */
+static void rds_ib_remove_one(struct ib_device *device)
+{
+ struct rds_ib_device *rds_ibdev;
+
+ rds_ibdev = ib_get_client_data(device, &rds_ib_client);
+ if (!rds_ibdev)
+ return;
+
+ rds_ib_dev_shutdown(rds_ibdev);
+
+ /* stop connection attempts from getting a reference to this device. */
+ ib_set_client_data(device, &rds_ib_client, NULL);
+
+ down_write(&rds_ib_devices_lock);
+ list_del_rcu(&rds_ibdev->list);
+ up_write(&rds_ib_devices_lock);
+
+ /*
+ * This synchronize rcu is waiting for readers of both the ib
+ * client data and the devices list to finish before we drop
+ * both of those references.
+ */
+ synchronize_rcu();
+ rds_ib_dev_put(rds_ibdev);
+ rds_ib_dev_put(rds_ibdev);
+}
+
+struct ib_client rds_ib_client = {
+ .name = "rds_ib",
+ .add = rds_ib_add_one,
+ .remove = rds_ib_remove_one
+};
+
+static int rds_ib_conn_info_visitor(struct rds_connection *conn,
+ void *buffer)
+{
+ struct rds_info_rdma_connection *iinfo = buffer;
+ struct rds_ib_connection *ic;
+
+ /* We will only ever look at IB transports */
+ if (conn->c_trans != &rds_ib_transport)
+ return 0;
+
+ iinfo->src_addr = conn->c_laddr;
+ iinfo->dst_addr = conn->c_faddr;
+
+ memset(&iinfo->src_gid, 0, sizeof(iinfo->src_gid));
+ memset(&iinfo->dst_gid, 0, sizeof(iinfo->dst_gid));
+ if (rds_conn_state(conn) == RDS_CONN_UP) {
+ struct rds_ib_device *rds_ibdev;
+ struct rdma_dev_addr *dev_addr;
+
+ ic = conn->c_transport_data;
+ dev_addr = &ic->i_cm_id->route.addr.dev_addr;
+
+ rdma_addr_get_sgid(dev_addr, (union ib_gid *) &iinfo->src_gid);
+ rdma_addr_get_dgid(dev_addr, (union ib_gid *) &iinfo->dst_gid);
+
+ rds_ibdev = ic->rds_ibdev;
+ iinfo->max_send_wr = ic->i_send_ring.w_nr;
+ iinfo->max_recv_wr = ic->i_recv_ring.w_nr;
+ iinfo->max_send_sge = rds_ibdev->max_sge;
+ rds_ib_get_mr_info(rds_ibdev, iinfo);
+ }
+ return 1;
+}
+
+static void rds_ib_ic_info(struct socket *sock, unsigned int len,
+ struct rds_info_iterator *iter,
+ struct rds_info_lengths *lens)
+{
+ rds_for_each_conn_info(sock, len, iter, lens,
+ rds_ib_conn_info_visitor,
+ sizeof(struct rds_info_rdma_connection));
+}
+
+
+/*
+ * Early RDS/IB was built to only bind to an address if there is an IPoIB
+ * device with that address set.
+ *
+ * If it were me, I'd advocate for something more flexible. Sending and
+ * receiving should be device-agnostic. Transports would try and maintain
+ * connections between peers who have messages queued. Userspace would be
+ * allowed to influence which paths have priority. We could call userspace
+ * asserting this policy "routing".
+ */
+static int rds_ib_laddr_check(__be32 addr)
+{
+ int ret;
+ struct rdma_cm_id *cm_id;
+ struct sockaddr_in sin;
+
+ /* Create a CMA ID and try to bind it. This catches both
+ * IB and iWARP capable NICs.
+ */
+ cm_id = rdma_create_id(NULL, NULL, RDMA_PS_TCP, IB_QPT_RC);
+ if (IS_ERR(cm_id))
+ return PTR_ERR(cm_id);
+
+ memset(&sin, 0, sizeof(sin));
+ sin.sin_family = AF_INET;
+ sin.sin_addr.s_addr = addr;
+
+ /* rdma_bind_addr will only succeed for IB & iWARP devices */
+ ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
+ /* due to this, we will claim to support iWARP devices unless we
+ check node_type. */
+ if (ret || !cm_id->device ||
+ cm_id->device->node_type != RDMA_NODE_IB_CA)
+ ret = -EADDRNOTAVAIL;
+
+ rdsdebug("addr %pI4 ret %d node type %d\n",
+ &addr, ret,
+ cm_id->device ? cm_id->device->node_type : -1);
+
+ rdma_destroy_id(cm_id);
+
+ return ret;
+}
+
+static void rds_ib_unregister_client(void)
+{
+ ib_unregister_client(&rds_ib_client);
+ /* wait for rds_ib_dev_free() to complete */
+ flush_workqueue(rds_wq);
+}
+
+void rds_ib_exit(void)
+{
+ rds_info_deregister_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
+ rds_ib_unregister_client();
+ rds_ib_destroy_nodev_conns();
+ rds_ib_sysctl_exit();
+ rds_ib_recv_exit();
+ rds_trans_unregister(&rds_ib_transport);
+}
+
+struct rds_transport rds_ib_transport = {
+ .laddr_check = rds_ib_laddr_check,
+ .xmit_complete = rds_ib_xmit_complete,
+ .xmit = rds_ib_xmit,
+ .xmit_rdma = rds_ib_xmit_rdma,
+ .xmit_atomic = rds_ib_xmit_atomic,
+ .recv = rds_ib_recv,
+ .conn_alloc = rds_ib_conn_alloc,
+ .conn_free = rds_ib_conn_free,
+ .conn_connect = rds_ib_conn_connect,
+ .conn_shutdown = rds_ib_conn_shutdown,
+ .inc_copy_to_user = rds_ib_inc_copy_to_user,
+ .inc_free = rds_ib_inc_free,
+ .cm_initiate_connect = rds_ib_cm_initiate_connect,
+ .cm_handle_connect = rds_ib_cm_handle_connect,
+ .cm_connect_complete = rds_ib_cm_connect_complete,
+ .stats_info_copy = rds_ib_stats_info_copy,
+ .exit = rds_ib_exit,
+ .get_mr = rds_ib_get_mr,
+ .sync_mr = rds_ib_sync_mr,
+ .free_mr = rds_ib_free_mr,
+ .flush_mrs = rds_ib_flush_mrs,
+ .t_owner = THIS_MODULE,
+ .t_name = "infiniband",
+ .t_type = RDS_TRANS_IB
+};
+
+int rds_ib_init(void)
+{
+ int ret;
+
+ INIT_LIST_HEAD(&rds_ib_devices);
+
+ ret = ib_register_client(&rds_ib_client);
+ if (ret)
+ goto out;
+
+ ret = rds_ib_sysctl_init();
+ if (ret)
+ goto out_ibreg;
+
+ ret = rds_ib_recv_init();
+ if (ret)
+ goto out_sysctl;
+
+ ret = rds_trans_register(&rds_ib_transport);
+ if (ret)
+ goto out_recv;
+
+ rds_info_register_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
+
+ goto out;
+
+out_recv:
+ rds_ib_recv_exit();
+out_sysctl:
+ rds_ib_sysctl_exit();
+out_ibreg:
+ rds_ib_unregister_client();
+out:
+ return ret;
+}
+
+MODULE_LICENSE("GPL");
+
Code Review / kvmfornfv.git / blobdiff