/*
* 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 qp->s_lock held.
*/
void ipath_cq_enter(struct ipath_cq *cq, struct ib_wc *entry, int solicited)
{
struct ipath_cq_wc *wc = cq->queue;
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.
*/
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;
}
wc->queue[head] = *entry;
wc->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);
struct ipath_cq_wc *wc = cq->queue;
unsigned long flags;
int npolled;
spin_lock_irqsave(&cq->lock, flags);
for (npolled = 0; npolled < num_entries; ++npolled, ++entry) {
if (wc->tail == wc->head)
break;
*entry = wc->queue[wc->tail];
if (wc->tail >= cq->ibcq.cqe)
wc->tail = 0;
else
wc->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_ibdev *dev = to_idev(ibdev);
struct ipath_cq *cq;
struct ipath_cq_wc *wc;
struct ib_cq *ret;
if (entries < 1 || entries > ib_ipath_max_cqes) {
ret = ERR_PTR(-EINVAL);
goto done;
}
if (dev->n_cqs_allocated == ib_ipath_max_cqs) {
ret = ERR_PTR(-ENOMEM);
goto done;
}
/* Allocate the completion queue structure. */
cq = kmalloc(sizeof(*cq), GFP_KERNEL);
if (!cq) {
ret = ERR_PTR(-ENOMEM);
goto done;
}
/*
* 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.
*/
wc = vmalloc_user(sizeof(*wc) + sizeof(struct ib_wc) * entries);
if (!wc) {
ret = ERR_PTR(-ENOMEM);
goto bail_cq;
}
/*
* Return the address of the WC as the offset to mmap.
* See ipath_mmap() for details.
*/
if (udata && udata->outlen >= sizeof(__u64)) {
struct ipath_mmap_info *ip;
__u64 offset = (__u64) wc;
int err;
err = ib_copy_to_udata(udata, &offset, sizeof(offset));
if (err) {
ret = ERR_PTR(err);
goto bail_wc;
}
/* Allocate info for ipath_mmap(). */
ip = kmalloc(sizeof(*ip), GFP_KERNEL);
if (!ip) {
ret = ERR_PTR(-ENOMEM);
goto bail_wc;
}
cq->ip = ip;
ip->context = context;
ip->obj = wc;
kref_init(&ip->ref);
ip->mmap_cnt = 0;
ip->size = PAGE_ALIGN(sizeof(*wc) +
sizeof(struct ib_wc) * entries);
spin_lock_irq(&dev->pending_lock);
ip->next = dev->pending_mmaps;
dev->pending_mmaps = ip;
spin_unlock_irq(&dev->pending_lock);
} else
cq->ip = NULL;
/*
* 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);
wc->head = 0;
wc->tail = 0;
cq->queue = wc;
ret = &cq->ibcq;
dev->n_cqs_allocated++;
goto done;
bail_wc:
vfree(wc);
bail_cq:
kfree(cq);
done:
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_ibdev *dev = to_idev(ibcq->device);
struct ipath_cq *cq = to_icq(ibcq);
tasklet_kill(&cq->comptask);
dev->n_cqs_allocated--;
if (cq->ip)
kref_put(&cq->ip->ref, ipath_release_mmap_info);
else
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 (see C11-31 and C11-32 in ch. 11.4.2.2).
*/
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 ipath_cq_wc *old_wc = cq->queue;
struct ipath_cq_wc *wc;
u32 head, tail, n;
int ret;
if (cqe < 1 || cqe > ib_ipath_max_cqes) {
ret = -EINVAL;
goto bail;
}
/*
* Need to use vmalloc() if we want to support large #s of entries.
*/
wc = vmalloc_user(sizeof(*wc) + sizeof(struct ib_wc) * cqe);
if (!wc) {
ret = -ENOMEM;
goto bail;
}
/*
* Return the address of the WC as the offset to mmap.
* See ipath_mmap() for details.
*/
if (udata && udata->outlen >= sizeof(__u64)) {
__u64 offset = (__u64) wc;
ret = ib_copy_to_udata(udata, &offset, sizeof(offset));
if (ret)
goto bail;
}
spin_lock_irq(&cq->lock);
/*
* Make sure head and tail are sane since they
* might be user writable.
*/
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)) {
spin_unlock_irq(&cq->lock);
vfree(wc);
ret = -EOVERFLOW;
goto bail;
}
for (n = 0; tail != head; n++) {
wc->queue[n] = old_wc->queue[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 ipath_ibdev *dev = to_idev(ibcq->device);
struct ipath_mmap_info *ip = cq->ip;
ip->obj = wc;
ip->size = PAGE_ALIGN(sizeof(*wc) +
sizeof(struct ib_wc) * cqe);
spin_lock_irq(&dev->pending_lock);
ip->next = dev->pending_mmaps;
dev->pending_mmaps = ip;
spin_unlock_irq(&dev->pending_lock);
}
ret = 0;
bail:
return ret;
}
