/*
* 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->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");
