| /* |
| * Copyright (c) 2006 QLogic, Inc. All rights reserved. |
| * Copyright (c) 2005, 2006 PathScale, Inc. 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/list.h> |
| #include <linux/rcupdate.h> |
| |
| #include "ipath_verbs.h" |
| |
| /* |
| * Global table of GID to attached QPs. |
| * The table is global to all ipath devices since a send from one QP/device |
| * needs to be locally routed to any locally attached QPs on the same |
| * or different device. |
| */ |
| static struct rb_root mcast_tree; |
| static DEFINE_SPINLOCK(mcast_lock); |
| |
| /** |
| * ipath_mcast_qp_alloc - alloc a struct to link a QP to mcast GID struct |
| * @qp: the QP to link |
| */ |
| static struct ipath_mcast_qp *ipath_mcast_qp_alloc(struct ipath_qp *qp) |
| { |
| struct ipath_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 ipath_mcast_qp_free(struct ipath_mcast_qp *mqp) |
| { |
| struct ipath_qp *qp = mqp->qp; |
| |
| /* Notify ipath_destroy_qp() if it is waiting. */ |
| if (atomic_dec_and_test(&qp->refcount)) |
| wake_up(&qp->wait); |
| |
| kfree(mqp); |
| } |
| |
| /** |
| * ipath_mcast_alloc - allocate the multicast GID structure |
| * @mgid: the multicast GID |
| * |
| * A list of QPs will be attached to this structure. |
| */ |
| static struct ipath_mcast *ipath_mcast_alloc(union ib_gid *mgid) |
| { |
| struct ipath_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 ipath_mcast_free(struct ipath_mcast *mcast) |
| { |
| struct ipath_mcast_qp *p, *tmp; |
| |
| list_for_each_entry_safe(p, tmp, &mcast->qp_list, list) |
| ipath_mcast_qp_free(p); |
| |
| kfree(mcast); |
| } |
| |
| /** |
| * ipath_mcast_find - search the global table for the given multicast GID |
| * @mgid: the multicast GID to search for |
| * |
| * Returns NULL if not found. |
| * |
| * The caller is responsible for decrementing the reference count if found. |
| */ |
| struct ipath_mcast *ipath_mcast_find(union ib_gid *mgid) |
| { |
| struct rb_node *n; |
| unsigned long flags; |
| struct ipath_mcast *mcast; |
| |
| spin_lock_irqsave(&mcast_lock, flags); |
| n = mcast_tree.rb_node; |
| while (n) { |
| int ret; |
| |
| mcast = rb_entry(n, struct ipath_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(&mcast_lock, flags); |
| goto bail; |
| } |
| } |
| spin_unlock_irqrestore(&mcast_lock, flags); |
| |
| mcast = NULL; |
| |
| bail: |
| return mcast; |
| } |
| |
| /** |
| * ipath_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 ipath_mcast_add(struct ipath_ibdev *dev, |
| struct ipath_mcast *mcast, |
| struct ipath_mcast_qp *mqp) |
| { |
| struct rb_node **n = &mcast_tree.rb_node; |
| struct rb_node *pn = NULL; |
| unsigned long flags; |
| int ret; |
| |
| spin_lock_irqsave(&mcast_lock, flags); |
| |
| while (*n) { |
| struct ipath_mcast *tmcast; |
| struct ipath_mcast_qp *p; |
| |
| pn = *n; |
| tmcast = rb_entry(pn, struct ipath_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 == ib_ipath_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 == ib_ipath_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); |
| |
| 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, &mcast_tree); |
| |
| ret = 0; |
| |
| bail: |
| spin_unlock_irqrestore(&mcast_lock, flags); |
| |
| return ret; |
| } |
| |
| int ipath_multicast_attach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid) |
| { |
| struct ipath_qp *qp = to_iqp(ibqp); |
| struct ipath_ibdev *dev = to_idev(ibqp->device); |
| struct ipath_mcast *mcast; |
| struct ipath_mcast_qp *mqp; |
| int ret; |
| |
| /* |
| * Allocate data structures since its better to do this outside of |
| * spin locks and it will most likely be needed. |
| */ |
| mcast = ipath_mcast_alloc(gid); |
| if (mcast == NULL) { |
| ret = -ENOMEM; |
| goto bail; |
| } |
| mqp = ipath_mcast_qp_alloc(qp); |
| if (mqp == NULL) { |
| ipath_mcast_free(mcast); |
| ret = -ENOMEM; |
| goto bail; |
| } |
| switch (ipath_mcast_add(dev, mcast, mqp)) { |
| case ESRCH: |
| /* Neither was used: can't attach the same QP twice. */ |
| ipath_mcast_qp_free(mqp); |
| ipath_mcast_free(mcast); |
| ret = -EINVAL; |
| goto bail; |
| case EEXIST: /* The mcast wasn't used */ |
| ipath_mcast_free(mcast); |
| break; |
| case ENOMEM: |
| /* Exceeded the maximum number of mcast groups. */ |
| ipath_mcast_qp_free(mqp); |
| ipath_mcast_free(mcast); |
| ret = -ENOMEM; |
| goto bail; |
| default: |
| break; |
| } |
| |
| ret = 0; |
| |
| bail: |
| return ret; |
| } |
| |
| int ipath_multicast_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid) |
| { |
| struct ipath_qp *qp = to_iqp(ibqp); |
| struct ipath_ibdev *dev = to_idev(ibqp->device); |
| struct ipath_mcast *mcast = NULL; |
| struct ipath_mcast_qp *p, *tmp; |
| struct rb_node *n; |
| unsigned long flags; |
| int last = 0; |
| int ret; |
| |
| spin_lock_irqsave(&mcast_lock, flags); |
| |
| /* Find the GID in the mcast table. */ |
| n = mcast_tree.rb_node; |
| while (1) { |
| if (n == NULL) { |
| spin_unlock_irqrestore(&mcast_lock, flags); |
| ret = -EINVAL; |
| goto bail; |
| } |
| |
| mcast = rb_entry(n, struct ipath_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, &mcast_tree); |
| last = 1; |
| } |
| break; |
| } |
| |
| spin_unlock_irqrestore(&mcast_lock, flags); |
| |
| if (p) { |
| /* |
| * Wait for any list walkers to finish before freeing the |
| * list element. |
| */ |
| wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1); |
| ipath_mcast_qp_free(p); |
| } |
| if (last) { |
| atomic_dec(&mcast->refcount); |
| wait_event(mcast->wait, !atomic_read(&mcast->refcount)); |
| ipath_mcast_free(mcast); |
| spin_lock(&dev->n_mcast_grps_lock); |
| dev->n_mcast_grps_allocated--; |
| spin_unlock(&dev->n_mcast_grps_lock); |
| } |
| |
| ret = 0; |
| |
| bail: |
| return ret; |
| } |
| |
| int ipath_mcast_tree_empty(void) |
| { |
| return mcast_tree.rb_node == NULL; |
| } |