blob: 59045bdce2a93e57ebcf88f00a339fd74497f03e [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
* Copyright(c) 2016 Intel Corporation.
*/
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/rculist.h>
#include <rdma/rdma_vt.h>
#include <rdma/rdmavt_qp.h>
#include "mcast.h"
/**
* rvt_driver_mcast_init - init resources for multicast
* @rdi: rvt dev struct
*
* This is per device that registers with rdmavt
*/
void rvt_driver_mcast_init(struct rvt_dev_info *rdi)
{
/*
* Anything that needs setup for multicast on a per driver or per rdi
* basis should be done in here.
*/
spin_lock_init(&rdi->n_mcast_grps_lock);
}
/**
* rvt_mcast_qp_alloc - alloc a struct to link a QP to mcast GID struct
* @qp: the QP to link
*/
static struct rvt_mcast_qp *rvt_mcast_qp_alloc(struct rvt_qp *qp)
{
struct rvt_mcast_qp *mqp;
mqp = kmalloc(sizeof(*mqp), GFP_KERNEL);
if (!mqp)
goto bail;
mqp->qp = qp;
rvt_get_qp(qp);
bail:
return mqp;
}
static void rvt_mcast_qp_free(struct rvt_mcast_qp *mqp)
{
struct rvt_qp *qp = mqp->qp;
/* Notify hfi1_destroy_qp() if it is waiting. */
rvt_put_qp(qp);
kfree(mqp);
}
/**
* rvt_mcast_alloc - allocate the multicast GID structure
* @mgid: the multicast GID
* @lid: the muilticast LID (host order)
*
* A list of QPs will be attached to this structure.
*/
static struct rvt_mcast *rvt_mcast_alloc(union ib_gid *mgid, u16 lid)
{
struct rvt_mcast *mcast;
mcast = kzalloc(sizeof(*mcast), GFP_KERNEL);
if (!mcast)
goto bail;
mcast->mcast_addr.mgid = *mgid;
mcast->mcast_addr.lid = lid;
INIT_LIST_HEAD(&mcast->qp_list);
init_waitqueue_head(&mcast->wait);
atomic_set(&mcast->refcount, 0);
bail:
return mcast;
}
static void rvt_mcast_free(struct rvt_mcast *mcast)
{
struct rvt_mcast_qp *p, *tmp;
list_for_each_entry_safe(p, tmp, &mcast->qp_list, list)
rvt_mcast_qp_free(p);
kfree(mcast);
}
/**
* rvt_mcast_find - search the global table for the given multicast GID/LID
* NOTE: It is valid to have 1 MLID with multiple MGIDs. It is not valid
* to have 1 MGID with multiple MLIDs.
* @ibp: the IB port structure
* @mgid: the multicast GID to search for
* @lid: the multicast LID portion of the multicast address (host order)
*
* The caller is responsible for decrementing the reference count if found.
*
* Return: NULL if not found.
*/
struct rvt_mcast *rvt_mcast_find(struct rvt_ibport *ibp, union ib_gid *mgid,
u16 lid)
{
struct rb_node *n;
unsigned long flags;
struct rvt_mcast *found = NULL;
spin_lock_irqsave(&ibp->lock, flags);
n = ibp->mcast_tree.rb_node;
while (n) {
int ret;
struct rvt_mcast *mcast;
mcast = rb_entry(n, struct rvt_mcast, rb_node);
ret = memcmp(mgid->raw, mcast->mcast_addr.mgid.raw,
sizeof(*mgid));
if (ret < 0) {
n = n->rb_left;
} else if (ret > 0) {
n = n->rb_right;
} else {
/* MGID/MLID must match */
if (mcast->mcast_addr.lid == lid) {
atomic_inc(&mcast->refcount);
found = mcast;
}
break;
}
}
spin_unlock_irqrestore(&ibp->lock, flags);
return found;
}
EXPORT_SYMBOL(rvt_mcast_find);
/*
* rvt_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. Return EINVAL if the MGID was
* found, but the MLID did NOT match.
*/
static int rvt_mcast_add(struct rvt_dev_info *rdi, struct rvt_ibport *ibp,
struct rvt_mcast *mcast, struct rvt_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 rvt_mcast *tmcast;
struct rvt_mcast_qp *p;
pn = *n;
tmcast = rb_entry(pn, struct rvt_mcast, rb_node);
ret = memcmp(mcast->mcast_addr.mgid.raw,
tmcast->mcast_addr.mgid.raw,
sizeof(mcast->mcast_addr.mgid));
if (ret < 0) {
n = &pn->rb_left;
continue;
}
if (ret > 0) {
n = &pn->rb_right;
continue;
}
if (tmcast->mcast_addr.lid != mcast->mcast_addr.lid) {
ret = EINVAL;
goto bail;
}
/* 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 ==
rdi->dparms.props.max_mcast_qp_attach) {
ret = ENOMEM;
goto bail;
}
tmcast->n_attached++;
list_add_tail_rcu(&mqp->list, &tmcast->qp_list);
ret = EEXIST;
goto bail;
}
spin_lock(&rdi->n_mcast_grps_lock);
if (rdi->n_mcast_grps_allocated == rdi->dparms.props.max_mcast_grp) {
spin_unlock(&rdi->n_mcast_grps_lock);
ret = ENOMEM;
goto bail;
}
rdi->n_mcast_grps_allocated++;
spin_unlock(&rdi->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;
}
/**
* rvt_attach_mcast - attach a qp to a multicast group
* @ibqp: Infiniband qp
* @gid: multicast guid
* @lid: multicast lid
*
* Return: 0 on success
*/
int rvt_attach_mcast(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
{
struct rvt_qp *qp = ibqp_to_rvtqp(ibqp);
struct rvt_dev_info *rdi = ib_to_rvt(ibqp->device);
struct rvt_ibport *ibp = rdi->ports[qp->port_num - 1];
struct rvt_mcast *mcast;
struct rvt_mcast_qp *mqp;
int ret = -ENOMEM;
if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET)
return -EINVAL;
/*
* Allocate data structures since its better to do this outside of
* spin locks and it will most likely be needed.
*/
mcast = rvt_mcast_alloc(gid, lid);
if (!mcast)
return -ENOMEM;
mqp = rvt_mcast_qp_alloc(qp);
if (!mqp)
goto bail_mcast;
switch (rvt_mcast_add(rdi, ibp, mcast, mqp)) {
case ESRCH:
/* Neither was used: OK to attach the same QP twice. */
ret = 0;
goto bail_mqp;
case EEXIST: /* The mcast wasn't used */
ret = 0;
goto bail_mcast;
case ENOMEM:
/* Exceeded the maximum number of mcast groups. */
ret = -ENOMEM;
goto bail_mqp;
case EINVAL:
/* Invalid MGID/MLID pair */
ret = -EINVAL;
goto bail_mqp;
default:
break;
}
return 0;
bail_mqp:
rvt_mcast_qp_free(mqp);
bail_mcast:
rvt_mcast_free(mcast);
return ret;
}
/**
* rvt_detach_mcast - remove a qp from a multicast group
* @ibqp: Infiniband qp
* @gid: multicast guid
* @lid: multicast lid
*
* Return: 0 on success
*/
int rvt_detach_mcast(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
{
struct rvt_qp *qp = ibqp_to_rvtqp(ibqp);
struct rvt_dev_info *rdi = ib_to_rvt(ibqp->device);
struct rvt_ibport *ibp = rdi->ports[qp->port_num - 1];
struct rvt_mcast *mcast = NULL;
struct rvt_mcast_qp *p, *tmp, *delp = NULL;
struct rb_node *n;
int last = 0;
int ret = 0;
if (ibqp->qp_num <= 1)
return -EINVAL;
spin_lock_irq(&ibp->lock);
/* Find the GID in the mcast table. */
n = ibp->mcast_tree.rb_node;
while (1) {
if (!n) {
spin_unlock_irq(&ibp->lock);
return -EINVAL;
}
mcast = rb_entry(n, struct rvt_mcast, rb_node);
ret = memcmp(gid->raw, mcast->mcast_addr.mgid.raw,
sizeof(*gid));
if (ret < 0) {
n = n->rb_left;
} else if (ret > 0) {
n = n->rb_right;
} else {
/* MGID/MLID must match */
if (mcast->mcast_addr.lid != lid) {
spin_unlock_irq(&ibp->lock);
return -EINVAL;
}
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--;
delp = p;
/* 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);
/* QP not attached */
if (!delp)
return -EINVAL;
/*
* Wait for any list walkers to finish before freeing the
* list element.
*/
wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1);
rvt_mcast_qp_free(delp);
if (last) {
atomic_dec(&mcast->refcount);
wait_event(mcast->wait, !atomic_read(&mcast->refcount));
rvt_mcast_free(mcast);
spin_lock_irq(&rdi->n_mcast_grps_lock);
rdi->n_mcast_grps_allocated--;
spin_unlock_irq(&rdi->n_mcast_grps_lock);
}
return 0;
}
/**
* rvt_mcast_tree_empty - determine if any qps are attached to any mcast group
* @rdi: rvt dev struct
*
* Return: in use count
*/
int rvt_mcast_tree_empty(struct rvt_dev_info *rdi)
{
int i;
int in_use = 0;
for (i = 0; i < rdi->dparms.nports; i++)
if (rdi->ports[i]->mcast_tree.rb_node)
in_use++;
return in_use;
}