/*
* 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/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;
}
