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/*
* 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 "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
|