linux/net/rds/ib.c

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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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 09:04:11 +01:00
#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: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
/*
* 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/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
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);
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
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);
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
if (IS_ERR(rds_ibdev->pd)) {
rds_ibdev->pd = NULL;
goto put_dev;
}
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
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;
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
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);
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
atomic_inc(&rds_ibdev->refcount);
ib_set_client_data(device, &rds_ib_client, rds_ibdev);
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
atomic_inc(&rds_ibdev->refcount);
rds_ib_nodev_connect();
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
put_dev:
rds_ib_dev_put(rds_ibdev);
free_attr:
kfree(dev_attr);
}
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
/*
* 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);
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
/*
* 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.
RDS/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
*/
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/cm: fix loopback address support The RDMA CM is intended to support the use of a loopback address when establishing a connection; however, the behavior of the CM when loopback addresses are used is confusing and does not always work, depending on whether loopback was specified by the server, the client, or both. The defined behavior of rdma_bind_addr is to associate an RDMA device with an rdma_cm_id, as long as the user specified a non- zero address. (ie they weren't just trying to reserve a port) Currently, if the loopback address is passed to rdam_bind_addr, no device is associated with the rdma_cm_id. Fix this. If a loopback address is specified by the client as the destination address for a connection, it will fail to establish a connection. This is true even if the server is listing across all addresses or on the loopback address itself. The issue is that the server tries to translate the IP address carried in the REQ message to a local net_device address, which fails. The translation is not needed in this case, since the REQ carries the actual HW address that should be used. Finally, cleanup loopback support to be more transport neutral. Replace separate calls to get/set the sgid and dgid from the device address to a single call that behaves correctly depending on the format of the device address. And support both IPv4 and IPv6 address formats. Signed-off-by: Sean Hefty <sean.hefty@intel.com> [ Fixed RDS build by s/ib_addr_get/rdma_addr_get/ - Roland ] Signed-off-by: Roland Dreier <rolandd@cisco.com>
2009-11-19 22:26:06 +01:00
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/IB: add refcount tracking to struct rds_ib_device The RDS IB client .remove callback used to free the rds_ibdev for the given device unconditionally. This could race other users of the struct. This patch adds refcounting so that we only free the rds_ibdev once all of its users are done. Many rds_ibdev users are tied to connections. We give the connection a reference and change these users to reference the device in the connection instead of looking it up in the IB client data. The only user of the IB client data remaining is the first lookup of the device as connections are built up. Incrementing the reference count of a device found in the IB client data could race with final freeing so we use an RCU grace period to make sure that freeing won't happen until those lookups are done. MRs need the rds_ibdev to get at the pool that they're freed in to. They exist outside a connection and many MRs can reference different devices from one socket, so it was natural to have each MR hold a reference. MR refs can be dropped from interrupt handlers and final device teardown can block so we push it off to a work struct. Pool teardown had to be fixed to cancel its pending work instead of deadlocking waiting for all queued work, including itself, to finish. MRs get their reference from the global device list, which gets a reference. It is left unprotected by locks and remains racy. A simple global lock would be a significant bottleneck. More scalable (complicated) locking should be done carefully in a later patch. Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-05-19 00:48:51 +02:00
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. */
rds: prevent dereference of a NULL device Binding might result in a NULL device, which is dereferenced causing this BUG: [ 1317.260548] BUG: unable to handle kernel NULL pointer dereference at 000000000000097 4 [ 1317.261847] IP: [<ffffffff84225f52>] rds_ib_laddr_check+0x82/0x110 [ 1317.263315] PGD 418bcb067 PUD 3ceb21067 PMD 0 [ 1317.263502] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 1317.264179] Dumping ftrace buffer: [ 1317.264774] (ftrace buffer empty) [ 1317.265220] Modules linked in: [ 1317.265824] CPU: 4 PID: 836 Comm: trinity-child46 Tainted: G W 3.13.0-rc4- next-20131218-sasha-00013-g2cebb9b-dirty #4159 [ 1317.267415] task: ffff8803ddf33000 ti: ffff8803cd31a000 task.ti: ffff8803cd31a000 [ 1317.268399] RIP: 0010:[<ffffffff84225f52>] [<ffffffff84225f52>] rds_ib_laddr_check+ 0x82/0x110 [ 1317.269670] RSP: 0000:ffff8803cd31bdf8 EFLAGS: 00010246 [ 1317.270230] RAX: 0000000000000000 RBX: ffff88020b0dd388 RCX: 0000000000000000 [ 1317.270230] RDX: ffffffff8439822e RSI: 00000000000c000a RDI: 0000000000000286 [ 1317.270230] RBP: ffff8803cd31be38 R08: 0000000000000000 R09: 0000000000000000 [ 1317.270230] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 [ 1317.270230] R13: 0000000054086700 R14: 0000000000a25de0 R15: 0000000000000031 [ 1317.270230] FS: 00007ff40251d700(0000) GS:ffff88022e200000(0000) knlGS:000000000000 0000 [ 1317.270230] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1317.270230] CR2: 0000000000000974 CR3: 00000003cd478000 CR4: 00000000000006e0 [ 1317.270230] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1317.270230] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000090602 [ 1317.270230] Stack: [ 1317.270230] 0000000054086700 5408670000a25de0 5408670000000002 0000000000000000 [ 1317.270230] ffffffff84223542 00000000ea54c767 0000000000000000 ffffffff86d26160 [ 1317.270230] ffff8803cd31be68 ffffffff84223556 ffff8803cd31beb8 ffff8800c6765280 [ 1317.270230] Call Trace: [ 1317.270230] [<ffffffff84223542>] ? rds_trans_get_preferred+0x42/0xa0 [ 1317.270230] [<ffffffff84223556>] rds_trans_get_preferred+0x56/0xa0 [ 1317.270230] [<ffffffff8421c9c3>] rds_bind+0x73/0xf0 [ 1317.270230] [<ffffffff83e4ce62>] SYSC_bind+0x92/0xf0 [ 1317.270230] [<ffffffff812493f8>] ? context_tracking_user_exit+0xb8/0x1d0 [ 1317.270230] [<ffffffff8119313d>] ? trace_hardirqs_on+0xd/0x10 [ 1317.270230] [<ffffffff8107a852>] ? syscall_trace_enter+0x32/0x290 [ 1317.270230] [<ffffffff83e4cece>] SyS_bind+0xe/0x10 [ 1317.270230] [<ffffffff843a6ad0>] tracesys+0xdd/0xe2 [ 1317.270230] Code: 00 8b 45 cc 48 8d 75 d0 48 c7 45 d8 00 00 00 00 66 c7 45 d0 02 00 89 45 d4 48 89 df e8 78 49 76 ff 41 89 c4 85 c0 75 0c 48 8b 03 <80> b8 74 09 00 00 01 7 4 06 41 bc 9d ff ff ff f6 05 2a b6 c2 02 [ 1317.270230] RIP [<ffffffff84225f52>] rds_ib_laddr_check+0x82/0x110 [ 1317.270230] RSP <ffff8803cd31bdf8> [ 1317.270230] CR2: 0000000000000974 Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-19 05:49:42 +01:00
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");