diff options
Diffstat (limited to 'drivers/infiniband/hw/ipath/ipath_cq.c')
-rw-r--r-- | drivers/infiniband/hw/ipath/ipath_cq.c | 295 |
1 files changed, 295 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/ipath/ipath_cq.c b/drivers/infiniband/hw/ipath/ipath_cq.c new file mode 100644 index 000000000000..7ece1135ddfe --- /dev/null +++ b/drivers/infiniband/hw/ipath/ipath_cq.c @@ -0,0 +1,295 @@ +/* + * 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/err.h> +#include <linux/vmalloc.h> + +#include "ipath_verbs.h" + +/** + * ipath_cq_enter - add a new entry to the completion queue + * @cq: completion queue + * @entry: work completion entry to add + * @sig: true if @entry is a solicitated entry + * + * This may be called with one of the qp->s_lock or qp->r_rq.lock held. + */ +void ipath_cq_enter(struct ipath_cq *cq, struct ib_wc *entry, int solicited) +{ + unsigned long flags; + u32 next; + + spin_lock_irqsave(&cq->lock, flags); + + if (cq->head == cq->ibcq.cqe) + next = 0; + else + next = cq->head + 1; + if (unlikely(next == cq->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; + } + cq->queue[cq->head] = *entry; + cq->head = next; + + if (cq->notify == IB_CQ_NEXT_COMP || + (cq->notify == IB_CQ_SOLICITED && solicited)) { + cq->notify = IB_CQ_NONE; + cq->triggered++; + /* + * This will cause send_complete() to be called in + * another thread. + */ + tasklet_hi_schedule(&cq->comptask); + } + + spin_unlock_irqrestore(&cq->lock, flags); + + if (entry->status != IB_WC_SUCCESS) + to_idev(cq->ibcq.device)->n_wqe_errs++; +} + +/** + * ipath_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 + * + * Returns the number of completion entries polled. + * + * This may be called from interrupt context. Also called by ib_poll_cq() + * in the generic verbs code. + */ +int ipath_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry) +{ + struct ipath_cq *cq = to_icq(ibcq); + unsigned long flags; + int npolled; + + spin_lock_irqsave(&cq->lock, flags); + + for (npolled = 0; npolled < num_entries; ++npolled, ++entry) { + if (cq->tail == cq->head) + break; + *entry = cq->queue[cq->tail]; + if (cq->tail == cq->ibcq.cqe) + cq->tail = 0; + else + cq->tail++; + } + + spin_unlock_irqrestore(&cq->lock, flags); + + return npolled; +} + +static void send_complete(unsigned long data) +{ + struct ipath_cq *cq = (struct ipath_cq *)data; + + /* + * 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, tasklet_hi_schedule() + * 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; + + cq->ibcq.comp_handler(&cq->ibcq, cq->ibcq.cq_context); + + if (cq->triggered == triggered) + return; + } +} + +/** + * ipath_create_cq - create a completion queue + * @ibdev: the device this completion queue is attached to + * @entries: the minimum size of the completion queue + * @context: unused by the InfiniPath driver + * @udata: unused by the InfiniPath driver + * + * Returns a pointer to the completion queue or negative errno values + * for failure. + * + * Called by ib_create_cq() in the generic verbs code. + */ +struct ib_cq *ipath_create_cq(struct ib_device *ibdev, int entries, + struct ib_ucontext *context, + struct ib_udata *udata) +{ + struct ipath_cq *cq; + struct ib_wc *wc; + struct ib_cq *ret; + + /* + * Need to use vmalloc() if we want to support large #s of + * entries. + */ + cq = kmalloc(sizeof(*cq), GFP_KERNEL); + if (!cq) { + ret = ERR_PTR(-ENOMEM); + goto bail; + } + + /* + * Need to use vmalloc() if we want to support large #s of entries. + */ + wc = vmalloc(sizeof(*wc) * (entries + 1)); + if (!wc) { + kfree(cq); + ret = ERR_PTR(-ENOMEM); + goto bail; + } + /* + * 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->ibcq.cqe = entries; + cq->notify = IB_CQ_NONE; + cq->triggered = 0; + spin_lock_init(&cq->lock); + tasklet_init(&cq->comptask, send_complete, (unsigned long)cq); + cq->head = 0; + cq->tail = 0; + cq->queue = wc; + + ret = &cq->ibcq; + +bail: + return ret; +} + +/** + * ipath_destroy_cq - destroy a completion queue + * @ibcq: the completion queue to destroy. + * + * Returns 0 for success. + * + * Called by ib_destroy_cq() in the generic verbs code. + */ +int ipath_destroy_cq(struct ib_cq *ibcq) +{ + struct ipath_cq *cq = to_icq(ibcq); + + tasklet_kill(&cq->comptask); + vfree(cq->queue); + kfree(cq); + + return 0; +} + +/** + * ipath_req_notify_cq - change the notification type for a completion queue + * @ibcq: the completion queue + * @notify: the type of notification to request + * + * Returns 0 for success. + * + * This may be called from interrupt context. Also called by + * ib_req_notify_cq() in the generic verbs code. + */ +int ipath_req_notify_cq(struct ib_cq *ibcq, enum ib_cq_notify notify) +{ + struct ipath_cq *cq = to_icq(ibcq); + unsigned long flags; + + spin_lock_irqsave(&cq->lock, flags); + /* + * Don't change IB_CQ_NEXT_COMP to IB_CQ_SOLICITED but allow + * any other transitions. + */ + if (cq->notify != IB_CQ_NEXT_COMP) + cq->notify = notify; + spin_unlock_irqrestore(&cq->lock, flags); + return 0; +} + +int ipath_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata) +{ + struct ipath_cq *cq = to_icq(ibcq); + struct ib_wc *wc, *old_wc; + u32 n; + int ret; + + /* + * Need to use vmalloc() if we want to support large #s of entries. + */ + wc = vmalloc(sizeof(*wc) * (cqe + 1)); + if (!wc) { + ret = -ENOMEM; + goto bail; + } + + spin_lock_irq(&cq->lock); + if (cq->head < cq->tail) + n = cq->ibcq.cqe + 1 + cq->head - cq->tail; + else + n = cq->head - cq->tail; + if (unlikely((u32)cqe < n)) { + spin_unlock_irq(&cq->lock); + vfree(wc); + ret = -EOVERFLOW; + goto bail; + } + for (n = 0; cq->tail != cq->head; n++) { + wc[n] = cq->queue[cq->tail]; + if (cq->tail == cq->ibcq.cqe) + cq->tail = 0; + else + cq->tail++; + } + cq->ibcq.cqe = cqe; + cq->head = n; + cq->tail = 0; + old_wc = cq->queue; + cq->queue = wc; + spin_unlock_irq(&cq->lock); + + vfree(old_wc); + + ret = 0; + +bail: + return ret; +} |