blob: afc6b4c61a1d3e6b5f51ee8df014200aa00c3149 [file] [log] [blame]
/*
*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
*
* GPL LICENSE SUMMARY
*
* Copyright(c) 2015 Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* BSD LICENSE
*
* Copyright(c) 2015 Intel Corporation.
*
* 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.
* - Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <linux/rculist.h>
#include "hfi.h"
/**
* mcast_qp_alloc - alloc a struct to link a QP to mcast GID struct
* @qp: the QP to link
*/
static struct hfi1_mcast_qp *mcast_qp_alloc(struct hfi1_qp *qp)
{
struct hfi1_mcast_qp *mqp;
mqp = kmalloc(sizeof(*mqp), GFP_KERNEL);
if (!mqp)
goto bail;
mqp->qp = qp;
atomic_inc(&qp->refcount);
bail:
return mqp;
}
static void mcast_qp_free(struct hfi1_mcast_qp *mqp)
{
struct hfi1_qp *qp = mqp->qp;
/* Notify hfi1_destroy_qp() if it is waiting. */
if (atomic_dec_and_test(&qp->refcount))
wake_up(&qp->wait);
kfree(mqp);
}
/**
* mcast_alloc - allocate the multicast GID structure
* @mgid: the multicast GID
*
* A list of QPs will be attached to this structure.
*/
static struct hfi1_mcast *mcast_alloc(union ib_gid *mgid)
{
struct hfi1_mcast *mcast;
mcast = kmalloc(sizeof(*mcast), GFP_KERNEL);
if (!mcast)
goto bail;
mcast->mgid = *mgid;
INIT_LIST_HEAD(&mcast->qp_list);
init_waitqueue_head(&mcast->wait);
atomic_set(&mcast->refcount, 0);
mcast->n_attached = 0;
bail:
return mcast;
}
static void mcast_free(struct hfi1_mcast *mcast)
{
struct hfi1_mcast_qp *p, *tmp;
list_for_each_entry_safe(p, tmp, &mcast->qp_list, list)
mcast_qp_free(p);
kfree(mcast);
}
/**
* hfi1_mcast_find - search the global table for the given multicast GID
* @ibp: the IB port structure
* @mgid: the multicast GID to search for
*
* Returns NULL if not found.
*
* The caller is responsible for decrementing the reference count if found.
*/
struct hfi1_mcast *hfi1_mcast_find(struct hfi1_ibport *ibp, union ib_gid *mgid)
{
struct rb_node *n;
unsigned long flags;
struct hfi1_mcast *mcast;
spin_lock_irqsave(&ibp->lock, flags);
n = ibp->mcast_tree.rb_node;
while (n) {
int ret;
mcast = rb_entry(n, struct hfi1_mcast, rb_node);
ret = memcmp(mgid->raw, mcast->mgid.raw,
sizeof(union ib_gid));
if (ret < 0)
n = n->rb_left;
else if (ret > 0)
n = n->rb_right;
else {
atomic_inc(&mcast->refcount);
spin_unlock_irqrestore(&ibp->lock, flags);
goto bail;
}
}
spin_unlock_irqrestore(&ibp->lock, flags);
mcast = NULL;
bail:
return mcast;
}
/**
* mcast_add - insert mcast GID into table and attach QP struct
* @mcast: the mcast GID table
* @mqp: the QP to attach
*
* Return zero if both were added. Return EEXIST if the GID was already in
* the table but the QP was added. Return ESRCH if the QP was already
* attached and neither structure was added.
*/
static int mcast_add(struct hfi1_ibdev *dev, struct hfi1_ibport *ibp,
struct hfi1_mcast *mcast, struct hfi1_mcast_qp *mqp)
{
struct rb_node **n = &ibp->mcast_tree.rb_node;
struct rb_node *pn = NULL;
int ret;
spin_lock_irq(&ibp->lock);
while (*n) {
struct hfi1_mcast *tmcast;
struct hfi1_mcast_qp *p;
pn = *n;
tmcast = rb_entry(pn, struct hfi1_mcast, rb_node);
ret = memcmp(mcast->mgid.raw, tmcast->mgid.raw,
sizeof(union ib_gid));
if (ret < 0) {
n = &pn->rb_left;
continue;
}
if (ret > 0) {
n = &pn->rb_right;
continue;
}
/* Search the QP list to see if this is already there. */
list_for_each_entry_rcu(p, &tmcast->qp_list, list) {
if (p->qp == mqp->qp) {
ret = ESRCH;
goto bail;
}
}
if (tmcast->n_attached == hfi1_max_mcast_qp_attached) {
ret = ENOMEM;
goto bail;
}
tmcast->n_attached++;
list_add_tail_rcu(&mqp->list, &tmcast->qp_list);
ret = EEXIST;
goto bail;
}
spin_lock(&dev->n_mcast_grps_lock);
if (dev->n_mcast_grps_allocated == hfi1_max_mcast_grps) {
spin_unlock(&dev->n_mcast_grps_lock);
ret = ENOMEM;
goto bail;
}
dev->n_mcast_grps_allocated++;
spin_unlock(&dev->n_mcast_grps_lock);
mcast->n_attached++;
list_add_tail_rcu(&mqp->list, &mcast->qp_list);
atomic_inc(&mcast->refcount);
rb_link_node(&mcast->rb_node, pn, n);
rb_insert_color(&mcast->rb_node, &ibp->mcast_tree);
ret = 0;
bail:
spin_unlock_irq(&ibp->lock);
return ret;
}
int hfi1_multicast_attach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
{
struct hfi1_qp *qp = to_iqp(ibqp);
struct hfi1_ibdev *dev = to_idev(ibqp->device);
struct hfi1_ibport *ibp;
struct hfi1_mcast *mcast;
struct hfi1_mcast_qp *mqp;
int ret;
if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) {
ret = -EINVAL;
goto bail;
}
/*
* Allocate data structures since its better to do this outside of
* spin locks and it will most likely be needed.
*/
mcast = mcast_alloc(gid);
if (mcast == NULL) {
ret = -ENOMEM;
goto bail;
}
mqp = mcast_qp_alloc(qp);
if (mqp == NULL) {
mcast_free(mcast);
ret = -ENOMEM;
goto bail;
}
ibp = to_iport(ibqp->device, qp->port_num);
switch (mcast_add(dev, ibp, mcast, mqp)) {
case ESRCH:
/* Neither was used: OK to attach the same QP twice. */
mcast_qp_free(mqp);
mcast_free(mcast);
break;
case EEXIST: /* The mcast wasn't used */
mcast_free(mcast);
break;
case ENOMEM:
/* Exceeded the maximum number of mcast groups. */
mcast_qp_free(mqp);
mcast_free(mcast);
ret = -ENOMEM;
goto bail;
default:
break;
}
ret = 0;
bail:
return ret;
}
int hfi1_multicast_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
{
struct hfi1_qp *qp = to_iqp(ibqp);
struct hfi1_ibdev *dev = to_idev(ibqp->device);
struct hfi1_ibport *ibp = to_iport(ibqp->device, qp->port_num);
struct hfi1_mcast *mcast = NULL;
struct hfi1_mcast_qp *p, *tmp;
struct rb_node *n;
int last = 0;
int ret;
if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) {
ret = -EINVAL;
goto bail;
}
spin_lock_irq(&ibp->lock);
/* Find the GID in the mcast table. */
n = ibp->mcast_tree.rb_node;
while (1) {
if (n == NULL) {
spin_unlock_irq(&ibp->lock);
ret = -EINVAL;
goto bail;
}
mcast = rb_entry(n, struct hfi1_mcast, rb_node);
ret = memcmp(gid->raw, mcast->mgid.raw,
sizeof(union ib_gid));
if (ret < 0)
n = n->rb_left;
else if (ret > 0)
n = n->rb_right;
else
break;
}
/* Search the QP list. */
list_for_each_entry_safe(p, tmp, &mcast->qp_list, list) {
if (p->qp != qp)
continue;
/*
* We found it, so remove it, but don't poison the forward
* link until we are sure there are no list walkers.
*/
list_del_rcu(&p->list);
mcast->n_attached--;
/* If this was the last attached QP, remove the GID too. */
if (list_empty(&mcast->qp_list)) {
rb_erase(&mcast->rb_node, &ibp->mcast_tree);
last = 1;
}
break;
}
spin_unlock_irq(&ibp->lock);
if (p) {
/*
* Wait for any list walkers to finish before freeing the
* list element.
*/
wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1);
mcast_qp_free(p);
}
if (last) {
atomic_dec(&mcast->refcount);
wait_event(mcast->wait, !atomic_read(&mcast->refcount));
mcast_free(mcast);
spin_lock_irq(&dev->n_mcast_grps_lock);
dev->n_mcast_grps_allocated--;
spin_unlock_irq(&dev->n_mcast_grps_lock);
}
ret = 0;
bail:
return ret;
}
int hfi1_mcast_tree_empty(struct hfi1_ibport *ibp)
{
return ibp->mcast_tree.rb_node == NULL;
}