/*
* 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"
#include "trace.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;
}
trace_rvt_cq_enter(cq, entry, head);
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 = ib_lid_cpu16(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))) {
/*
* This will cause send_complete() to be called in
* another thread.
*/
spin_lock(&cq->rdi->n_cqs_lock);
if (likely(cq->rdi->worker)) {
cq->notify = RVT_CQ_NONE;
cq->triggered++;
kthread_queue_work(cq->rdi->worker, &cq->comptask);
}
spin_unlock(&cq->rdi->n_cqs_lock);
}
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_irq(&rdi->n_cqs_lock);
if (rdi->n_cqs_allocated == rdi->dparms.props.max_cq) {
spin_unlock_irq(&rdi->n_cqs_lock);
ret = ERR_PTR(-ENOMEM);
goto bail_ip;
}
rdi->n_cqs_allocated++;
spin_unlock_irq(&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);
kthread_init_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;
kthread_flush_work(&cq->comptask);
spin_lock_irq(&rdi->n_cqs_lock);
rdi->n_cqs_allocated--;
spin_unlock_irq(&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. */
trace_rvt_cq_poll(cq, &wc->kqueue[tail], npolled);
*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 cpu;
struct kthread_worker *worker;
if (rdi->worker)
return 0;
spin_lock_init(&rdi->n_cqs_lock);
cpu = cpumask_first(cpumask_of_node(rdi->dparms.node));
worker = kthread_create_worker_on_cpu(cpu, 0,
"%s", rdi->dparms.cq_name);
if (IS_ERR(worker))
return PTR_ERR(worker);
set_user_nice(worker->task, MIN_NICE);
rdi->worker = worker;
return 0;
}
/**
* rvt_cq_exit - tear down cq reources
* @rdi: rvt dev structure
*/
void rvt_cq_exit(struct rvt_dev_info *rdi)
{
struct kthread_worker *worker;
/* block future queuing from send_complete() */
spin_lock_irq(&rdi->n_cqs_lock);
worker = rdi->worker;
if (!worker) {
spin_unlock_irq(&rdi->n_cqs_lock);
return;
}
rdi->worker = NULL;
spin_unlock_irq(&rdi->n_cqs_lock);
kthread_destroy_worker(worker);
}
