diff options
Diffstat (limited to 'drivers/infiniband/sw/rdmavt/cq.c')
| -rw-r--r-- | drivers/infiniband/sw/rdmavt/cq.c | 551 |
1 files changed, 551 insertions, 0 deletions
diff --git a/drivers/infiniband/sw/rdmavt/cq.c b/drivers/infiniband/sw/rdmavt/cq.c new file mode 100644 index 000000000000..b1ffc8b4a6c0 --- /dev/null +++ b/drivers/infiniband/sw/rdmavt/cq.c @@ -0,0 +1,551 @@ +/* + * Copyright(c) 2016 Intel Corporation. + * + * 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 + * + * 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 + * + * 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/slab.h> +#include <linux/vmalloc.h> +#include <linux/kthread.h> +#include "cq.h" +#include "vt.h" + +/** + * rvt_cq_enter - add a new entry to the completion queue + * @cq: completion queue + * @entry: work completion entry to add + * @sig: true if @entry is solicited + * + * This may be called with qp->s_lock held. + */ +void rvt_cq_enter(struct rvt_cq *cq, struct ib_wc *entry, bool solicited) +{ + struct rvt_cq_wc *wc; + unsigned long flags; + u32 head; + u32 next; + + spin_lock_irqsave(&cq->lock, flags); + + /* + * Note that the head pointer might be writable by user processes. + * Take care to verify it is a sane value. + */ + wc = cq->queue; + head = wc->head; + if (head >= (unsigned)cq->ibcq.cqe) { + head = cq->ibcq.cqe; + next = 0; + } else { + next = head + 1; + } + + if (unlikely(next == wc->tail)) { + spin_unlock_irqrestore(&cq->lock, flags); + if (cq->ibcq.event_handler) { + struct ib_event ev; + + ev.device = cq->ibcq.device; + ev.element.cq = &cq->ibcq; + ev.event = IB_EVENT_CQ_ERR; + cq->ibcq.event_handler(&ev, cq->ibcq.cq_context); + } + return; + } + if (cq->ip) { + wc->uqueue[head].wr_id = entry->wr_id; + wc->uqueue[head].status = entry->status; + wc->uqueue[head].opcode = entry->opcode; + wc->uqueue[head].vendor_err = entry->vendor_err; + wc->uqueue[head].byte_len = entry->byte_len; + wc->uqueue[head].ex.imm_data = + (__u32 __force)entry->ex.imm_data; + wc->uqueue[head].qp_num = entry->qp->qp_num; + wc->uqueue[head].src_qp = entry->src_qp; + wc->uqueue[head].wc_flags = entry->wc_flags; + wc->uqueue[head].pkey_index = entry->pkey_index; + wc->uqueue[head].slid = entry->slid; + wc->uqueue[head].sl = entry->sl; + wc->uqueue[head].dlid_path_bits = entry->dlid_path_bits; + wc->uqueue[head].port_num = entry->port_num; + /* Make sure entry is written before the head index. */ + smp_wmb(); + } else { + wc->kqueue[head] = *entry; + } + wc->head = next; + + if (cq->notify == IB_CQ_NEXT_COMP || + (cq->notify == IB_CQ_SOLICITED && + (solicited || entry->status != IB_WC_SUCCESS))) { + struct kthread_worker *worker; + /* + * This will cause send_complete() to be called in + * another thread. + */ + smp_read_barrier_depends(); /* see rvt_cq_exit */ + worker = cq->rdi->worker; + if (likely(worker)) { + cq->notify = RVT_CQ_NONE; + cq->triggered++; + queue_kthread_work(worker, &cq->comptask); + } + } + + spin_unlock_irqrestore(&cq->lock, flags); +} +EXPORT_SYMBOL(rvt_cq_enter); + +static void send_complete(struct kthread_work *work) +{ + struct rvt_cq *cq = container_of(work, struct rvt_cq, comptask); + + /* + * The completion handler will most likely rearm the notification + * and poll for all pending entries. If a new completion entry + * is added while we are in this routine, queue_work() + * won't call us again until we return so we check triggered to + * see if we need to call the handler again. + */ + for (;;) { + u8 triggered = cq->triggered; + + /* + * IPoIB connected mode assumes the callback is from a + * soft IRQ. We simulate this by blocking "bottom halves". + * See the implementation for ipoib_cm_handle_tx_wc(), + * netif_tx_lock_bh() and netif_tx_lock(). + */ + local_bh_disable(); + cq->ibcq.comp_handler(&cq->ibcq, cq->ibcq.cq_context); + local_bh_enable(); + + if (cq->triggered == triggered) + return; + } +} + +/** + * rvt_create_cq - create a completion queue + * @ibdev: the device this completion queue is attached to + * @attr: creation attributes + * @context: unused by the QLogic_IB driver + * @udata: user data for libibverbs.so + * + * Called by ib_create_cq() in the generic verbs code. + * + * Return: pointer to the completion queue or negative errno values + * for failure. + */ +struct ib_cq *rvt_create_cq(struct ib_device *ibdev, + const struct ib_cq_init_attr *attr, + struct ib_ucontext *context, + struct ib_udata *udata) +{ + struct rvt_dev_info *rdi = ib_to_rvt(ibdev); + struct rvt_cq *cq; + struct rvt_cq_wc *wc; + struct ib_cq *ret; + u32 sz; + unsigned int entries = attr->cqe; + + if (attr->flags) + return ERR_PTR(-EINVAL); + + if (entries < 1 || entries > rdi->dparms.props.max_cqe) + return ERR_PTR(-EINVAL); + + /* Allocate the completion queue structure. */ + cq = kzalloc(sizeof(*cq), GFP_KERNEL); + if (!cq) + return ERR_PTR(-ENOMEM); + + /* + * Allocate the completion queue entries and head/tail pointers. + * This is allocated separately so that it can be resized and + * also mapped into user space. + * We need to use vmalloc() in order to support mmap and large + * numbers of entries. + */ + sz = sizeof(*wc); + if (udata && udata->outlen >= sizeof(__u64)) + sz += sizeof(struct ib_uverbs_wc) * (entries + 1); + else + sz += sizeof(struct ib_wc) * (entries + 1); + wc = vmalloc_user(sz); + if (!wc) { + ret = ERR_PTR(-ENOMEM); + goto bail_cq; + } + + /* + * Return the address of the WC as the offset to mmap. + * See rvt_mmap() for details. + */ + if (udata && udata->outlen >= sizeof(__u64)) { + int err; + + cq->ip = rvt_create_mmap_info(rdi, sz, context, wc); + if (!cq->ip) { + ret = ERR_PTR(-ENOMEM); + goto bail_wc; + } + + err = ib_copy_to_udata(udata, &cq->ip->offset, + sizeof(cq->ip->offset)); + if (err) { + ret = ERR_PTR(err); + goto bail_ip; + } + } + + spin_lock(&rdi->n_cqs_lock); + if (rdi->n_cqs_allocated == rdi->dparms.props.max_cq) { + spin_unlock(&rdi->n_cqs_lock); + ret = ERR_PTR(-ENOMEM); + goto bail_ip; + } + + rdi->n_cqs_allocated++; + spin_unlock(&rdi->n_cqs_lock); + + if (cq->ip) { + spin_lock_irq(&rdi->pending_lock); + list_add(&cq->ip->pending_mmaps, &rdi->pending_mmaps); + spin_unlock_irq(&rdi->pending_lock); + } + + /* + * ib_create_cq() will initialize cq->ibcq except for cq->ibcq.cqe. + * The number of entries should be >= the number requested or return + * an error. + */ + cq->rdi = rdi; + cq->ibcq.cqe = entries; + cq->notify = RVT_CQ_NONE; + spin_lock_init(&cq->lock); + init_kthread_work(&cq->comptask, send_complete); + cq->queue = wc; + + ret = &cq->ibcq; + + goto done; + +bail_ip: + kfree(cq->ip); +bail_wc: + vfree(wc); +bail_cq: + kfree(cq); +done: + return ret; +} + +/** + * rvt_destroy_cq - destroy a completion queue + * @ibcq: the completion queue to destroy. + * + * Called by ib_destroy_cq() in the generic verbs code. + * + * Return: always 0 + */ +int rvt_destroy_cq(struct ib_cq *ibcq) +{ + struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); + struct rvt_dev_info *rdi = cq->rdi; + + flush_kthread_work(&cq->comptask); + spin_lock(&rdi->n_cqs_lock); + rdi->n_cqs_allocated--; + spin_unlock(&rdi->n_cqs_lock); + if (cq->ip) + kref_put(&cq->ip->ref, rvt_release_mmap_info); + else + vfree(cq->queue); + kfree(cq); + + return 0; +} + +/** + * rvt_req_notify_cq - change the notification type for a completion queue + * @ibcq: the completion queue + * @notify_flags: the type of notification to request + * + * This may be called from interrupt context. Also called by + * ib_req_notify_cq() in the generic verbs code. + * + * Return: 0 for success. + */ +int rvt_req_notify_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags notify_flags) +{ + struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&cq->lock, flags); + /* + * Don't change IB_CQ_NEXT_COMP to IB_CQ_SOLICITED but allow + * any other transitions (see C11-31 and C11-32 in ch. 11.4.2.2). + */ + if (cq->notify != IB_CQ_NEXT_COMP) + cq->notify = notify_flags & IB_CQ_SOLICITED_MASK; + + if ((notify_flags & IB_CQ_REPORT_MISSED_EVENTS) && + cq->queue->head != cq->queue->tail) + ret = 1; + + spin_unlock_irqrestore(&cq->lock, flags); + + return ret; +} + +/** + * rvt_resize_cq - change the size of the CQ + * @ibcq: the completion queue + * + * Return: 0 for success. + */ +int rvt_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata) +{ + struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); + struct rvt_cq_wc *old_wc; + struct rvt_cq_wc *wc; + u32 head, tail, n; + int ret; + u32 sz; + struct rvt_dev_info *rdi = cq->rdi; + + if (cqe < 1 || cqe > rdi->dparms.props.max_cqe) + return -EINVAL; + + /* + * Need to use vmalloc() if we want to support large #s of entries. + */ + sz = sizeof(*wc); + if (udata && udata->outlen >= sizeof(__u64)) + sz += sizeof(struct ib_uverbs_wc) * (cqe + 1); + else + sz += sizeof(struct ib_wc) * (cqe + 1); + wc = vmalloc_user(sz); + if (!wc) + return -ENOMEM; + + /* Check that we can write the offset to mmap. */ + if (udata && udata->outlen >= sizeof(__u64)) { + __u64 offset = 0; + + ret = ib_copy_to_udata(udata, &offset, sizeof(offset)); + if (ret) + goto bail_free; + } + + spin_lock_irq(&cq->lock); + /* + * Make sure head and tail are sane since they + * might be user writable. + */ + old_wc = cq->queue; + head = old_wc->head; + if (head > (u32)cq->ibcq.cqe) + head = (u32)cq->ibcq.cqe; + tail = old_wc->tail; + if (tail > (u32)cq->ibcq.cqe) + tail = (u32)cq->ibcq.cqe; + if (head < tail) + n = cq->ibcq.cqe + 1 + head - tail; + else + n = head - tail; + if (unlikely((u32)cqe < n)) { + ret = -EINVAL; + goto bail_unlock; + } + for (n = 0; tail != head; n++) { + if (cq->ip) + wc->uqueue[n] = old_wc->uqueue[tail]; + else + wc->kqueue[n] = old_wc->kqueue[tail]; + if (tail == (u32)cq->ibcq.cqe) + tail = 0; + else + tail++; + } + cq->ibcq.cqe = cqe; + wc->head = n; + wc->tail = 0; + cq->queue = wc; + spin_unlock_irq(&cq->lock); + + vfree(old_wc); + + if (cq->ip) { + struct rvt_mmap_info *ip = cq->ip; + + rvt_update_mmap_info(rdi, ip, sz, wc); + + /* + * Return the offset to mmap. + * See rvt_mmap() for details. + */ + if (udata && udata->outlen >= sizeof(__u64)) { + ret = ib_copy_to_udata(udata, &ip->offset, + sizeof(ip->offset)); + if (ret) + return ret; + } + + spin_lock_irq(&rdi->pending_lock); + if (list_empty(&ip->pending_mmaps)) + list_add(&ip->pending_mmaps, &rdi->pending_mmaps); + spin_unlock_irq(&rdi->pending_lock); + } + + return 0; + +bail_unlock: + spin_unlock_irq(&cq->lock); +bail_free: + vfree(wc); + return ret; +} + +/** + * rvt_poll_cq - poll for work completion entries + * @ibcq: the completion queue to poll + * @num_entries: the maximum number of entries to return + * @entry: pointer to array where work completions are placed + * + * This may be called from interrupt context. Also called by ib_poll_cq() + * in the generic verbs code. + * + * Return: the number of completion entries polled. + */ +int rvt_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry) +{ + struct rvt_cq *cq = ibcq_to_rvtcq(ibcq); + struct rvt_cq_wc *wc; + unsigned long flags; + int npolled; + u32 tail; + + /* The kernel can only poll a kernel completion queue */ + if (cq->ip) + return -EINVAL; + + spin_lock_irqsave(&cq->lock, flags); + + wc = cq->queue; + tail = wc->tail; + if (tail > (u32)cq->ibcq.cqe) + tail = (u32)cq->ibcq.cqe; + for (npolled = 0; npolled < num_entries; ++npolled, ++entry) { + if (tail == wc->head) + break; + /* The kernel doesn't need a RMB since it has the lock. */ + *entry = wc->kqueue[tail]; + if (tail >= cq->ibcq.cqe) + tail = 0; + else + tail++; + } + wc->tail = tail; + + spin_unlock_irqrestore(&cq->lock, flags); + + return npolled; +} + +/** + * rvt_driver_cq_init - Init cq resources on behalf of driver + * @rdi: rvt dev structure + * + * Return: 0 on success + */ +int rvt_driver_cq_init(struct rvt_dev_info *rdi) +{ + int ret = 0; + int cpu; + struct task_struct *task; + + if (rdi->worker) + return 0; + rdi->worker = kzalloc(sizeof(*rdi->worker), GFP_KERNEL); + if (!rdi->worker) + return -ENOMEM; + init_kthread_worker(rdi->worker); + task = kthread_create_on_node( + kthread_worker_fn, + rdi->worker, + rdi->dparms.node, + "%s", rdi->dparms.cq_name); + if (IS_ERR(task)) { + kfree(rdi->worker); + rdi->worker = NULL; + return PTR_ERR(task); + } + + cpu = cpumask_first(cpumask_of_node(rdi->dparms.node)); + kthread_bind(task, cpu); + wake_up_process(task); + return ret; +} + +/** + * rvt_cq_exit - tear down cq reources + * @rdi: rvt dev structure + */ +void rvt_cq_exit(struct rvt_dev_info *rdi) +{ + struct kthread_worker *worker; + + worker = rdi->worker; + if (!worker) + return; + /* blocks future queuing from send_complete() */ + rdi->worker = NULL; + smp_wmb(); /* See rdi_cq_enter */ + flush_kthread_worker(worker); + kthread_stop(worker->task); + kfree(worker); +} |