c2_cq.c

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/*
 * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
 * Copyright (c) 2005 Cisco Systems, Inc. All rights reserved.
 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
 * Copyright (c) 2004 Voltaire, Inc. All rights reserved.
 * Copyright (c) 2005 Open Grid Computing, 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/gfp.h>

#include "c2.h"
#include "c2_vq.h"
#include "c2_status.h"

#define C2_CQ_MSG_SIZE ((sizeof(struct c2wr_ce) + 32-1) & ~(32-1))

static struct c2_cq *c2_cq_get(struct c2_dev *c2dev, int cqn)
{
    struct c2_cq *cq;
    unsigned long flags;

    spin_lock_irqsave(&c2dev->lock, flags);
    cq = c2dev->qptr_array[cqn];
    if (!cq) {
        spin_unlock_irqrestore(&c2dev->lock, flags);
        return NULL;
    }
    atomic_inc(&cq->refcount);
    spin_unlock_irqrestore(&c2dev->lock, flags);
    return cq;
}

static void c2_cq_put(struct c2_cq *cq)
{
    if (atomic_dec_and_test(&cq->refcount))
        wake_up(&cq->wait);
}

void c2_cq_event(struct c2_dev *c2dev, u32 mq_index)
{
    struct c2_cq *cq;

    cq = c2_cq_get(c2dev, mq_index);
    if (!cq) {
        printk("discarding events on destroyed CQN=%d\n", mq_index);
        return;
    }

    (*cq->ibcq.comp_handler) (&cq->ibcq, cq->ibcq.cq_context);
    c2_cq_put(cq);
}

void c2_cq_clean(struct c2_dev *c2dev, struct c2_qp *qp, u32 mq_index)
{
    struct c2_cq *cq;
    struct c2_mq *q;

    cq = c2_cq_get(c2dev, mq_index);
    if (!cq)
        return;

    spin_lock_irq(&cq->lock);
    q = &cq->mq;
    if (q && !c2_mq_empty(q)) {
        u16 priv = q->priv;
        struct c2wr_ce *msg;

        while (priv != be16_to_cpu(*q->shared)) {
            msg = (struct c2wr_ce *)
                (q->msg_pool.host + priv * q->msg_size);
            if (msg->qp_user_context == (u64) (unsigned long) qp) {
                msg->qp_user_context = (u64) 0;
            }
            priv = (priv + 1) % q->q_size;
        }
    }
    spin_unlock_irq(&cq->lock);
    c2_cq_put(cq);
}

static inline enum ib_wc_status c2_cqe_status_to_openib(u8 status)
{
    switch (status) {
    case C2_OK:
        return IB_WC_SUCCESS;
    case CCERR_FLUSHED:
        return IB_WC_WR_FLUSH_ERR;
    case CCERR_BASE_AND_BOUNDS_VIOLATION:
        return IB_WC_LOC_PROT_ERR;
    case CCERR_ACCESS_VIOLATION:
        return IB_WC_LOC_ACCESS_ERR;
    case CCERR_TOTAL_LENGTH_TOO_BIG:
        return IB_WC_LOC_LEN_ERR;
    case CCERR_INVALID_WINDOW:
        return IB_WC_MW_BIND_ERR;
    default:
        return IB_WC_GENERAL_ERR;
    }
}


static inline int c2_poll_one(struct c2_dev *c2dev,
                  struct c2_cq *cq, struct ib_wc *entry)
{
    struct c2wr_ce *ce;
    struct c2_qp *qp;
    int is_recv = 0;

    ce = c2_mq_consume(&cq->mq);
    if (!ce) {
        return -EAGAIN;
    }

    /*
     * if the qp returned is null then this qp has already
     * been freed and we are unable process the completion.
     * try pulling the next message
     */
    while ((qp =
        (struct c2_qp *) (unsigned long) ce->qp_user_context) == NULL) {
        c2_mq_free(&cq->mq);
        ce = c2_mq_consume(&cq->mq);
        if (!ce)
            return -EAGAIN;
    }

    entry->status = c2_cqe_status_to_openib(c2_wr_get_result(ce));
    entry->wr_id = ce->hdr.context;
    entry->qp = &qp->ibqp;
    entry->wc_flags = 0;
    entry->slid = 0;
    entry->sl = 0;
    entry->src_qp = 0;
    entry->dlid_path_bits = 0;
    entry->pkey_index = 0;

    switch (c2_wr_get_id(ce)) {
    case C2_WR_TYPE_SEND:
        entry->opcode = IB_WC_SEND;
        break;
    case C2_WR_TYPE_RDMA_WRITE:
        entry->opcode = IB_WC_RDMA_WRITE;
        break;
    case C2_WR_TYPE_RDMA_READ:
        entry->opcode = IB_WC_RDMA_READ;
        break;
    case C2_WR_TYPE_BIND_MW:
        entry->opcode = IB_WC_BIND_MW;
        break;
    case C2_WR_TYPE_RECV:
        entry->byte_len = be32_to_cpu(ce->bytes_rcvd);
        entry->opcode = IB_WC_RECV;
        is_recv = 1;
        break;
    default:
        break;
    }

    /* consume the WQEs */
    if (is_recv)
        c2_mq_lconsume(&qp->rq_mq, 1);
    else
        c2_mq_lconsume(&qp->sq_mq,
                   be32_to_cpu(c2_wr_get_wqe_count(ce)) + 1);

    /* free the message */
    c2_mq_free(&cq->mq);

    return 0;
}

int c2_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry)
{
    struct c2_dev *c2dev = to_c2dev(ibcq->device);
    struct c2_cq *cq = to_c2cq(ibcq);
    unsigned long flags;
    int npolled, err;

    spin_lock_irqsave(&cq->lock, flags);

    for (npolled = 0; npolled < num_entries; ++npolled) {

        err = c2_poll_one(c2dev, cq, entry + npolled);
        if (err)
            break;
    }

    spin_unlock_irqrestore(&cq->lock, flags);

    return npolled;
}

int c2_arm_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags notify_flags)
{
    struct c2_mq_shared __iomem *shared;
    struct c2_cq *cq;
    unsigned long flags;
    int ret = 0;

    cq = to_c2cq(ibcq);
    shared = cq->mq.peer;

    if ((notify_flags & IB_CQ_SOLICITED_MASK) == IB_CQ_NEXT_COMP)
        writeb(C2_CQ_NOTIFICATION_TYPE_NEXT, &shared->notification_type);
    else if ((notify_flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED)
        writeb(C2_CQ_NOTIFICATION_TYPE_NEXT_SE, &shared->notification_type);
    else
        return -EINVAL;

    writeb(CQ_WAIT_FOR_DMA | CQ_ARMED, &shared->armed);

    /*
     * Now read back shared->armed to make the PCI
     * write synchronous.  This is necessary for
     * correct cq notification semantics.
     */
    readb(&shared->armed);

    if (notify_flags & IB_CQ_REPORT_MISSED_EVENTS) {
        spin_lock_irqsave(&cq->lock, flags);
        ret = !c2_mq_empty(&cq->mq);
        spin_unlock_irqrestore(&cq->lock, flags);
    }

    return ret;
}

static void c2_free_cq_buf(struct c2_dev *c2dev, struct c2_mq *mq)
{
    dma_free_coherent(&c2dev->pcidev->dev, mq->q_size * mq->msg_size,
              mq->msg_pool.host, dma_unmap_addr(mq, mapping));
}

static int c2_alloc_cq_buf(struct c2_dev *c2dev, struct c2_mq *mq, int q_size,
               int msg_size)
{
    u8 *pool_start;

    pool_start = dma_alloc_coherent(&c2dev->pcidev->dev, q_size * msg_size,
                    &mq->host_dma, GFP_KERNEL);
    if (!pool_start)
        return -ENOMEM;

    c2_mq_rep_init(mq,
               0,       /* index (currently unknown) */
               q_size,
               msg_size,
               pool_start,
               NULL,    /* peer (currently unknown) */
               C2_MQ_HOST_TARGET);

    dma_unmap_addr_set(mq, mapping, mq->host_dma);

    return 0;
}

int c2_init_cq(struct c2_dev *c2dev, int entries,
           struct c2_ucontext *ctx, struct c2_cq *cq)
{
    struct c2wr_cq_create_req wr;
    struct c2wr_cq_create_rep *reply;
    unsigned long peer_pa;
    struct c2_vq_req *vq_req;
    int err;

    might_sleep();

    cq->ibcq.cqe = entries - 1;
    cq->is_kernel = !ctx;

    /* Allocate a shared pointer */
    cq->mq.shared = c2_alloc_mqsp(c2dev, c2dev->kern_mqsp_pool,
                      &cq->mq.shared_dma, GFP_KERNEL);
    if (!cq->mq.shared)
        return -ENOMEM;

    /* Allocate pages for the message pool */
    err = c2_alloc_cq_buf(c2dev, &cq->mq, entries + 1, C2_CQ_MSG_SIZE);
    if (err)
        goto bail0;

    vq_req = vq_req_alloc(c2dev);
    if (!vq_req) {
        err = -ENOMEM;
        goto bail1;
    }

    memset(&wr, 0, sizeof(wr));
    c2_wr_set_id(&wr, CCWR_CQ_CREATE);
    wr.hdr.context = (unsigned long) vq_req;
    wr.rnic_handle = c2dev->adapter_handle;
    wr.msg_size = cpu_to_be32(cq->mq.msg_size);
    wr.depth = cpu_to_be32(cq->mq.q_size);
    wr.shared_ht = cpu_to_be64(cq->mq.shared_dma);
    wr.msg_pool = cpu_to_be64(cq->mq.host_dma);
    wr.user_context = (u64) (unsigned long) (cq);

    vq_req_get(c2dev, vq_req);

    err = vq_send_wr(c2dev, (union c2wr *) & wr);
    if (err) {
        vq_req_put(c2dev, vq_req);
        goto bail2;
    }

    err = vq_wait_for_reply(c2dev, vq_req);
    if (err)
        goto bail2;

    reply = (struct c2wr_cq_create_rep *) (unsigned long) (vq_req->reply_msg);
    if (!reply) {
        err = -ENOMEM;
        goto bail2;
    }

    if ((err = c2_errno(reply)) != 0)
        goto bail3;

    cq->adapter_handle = reply->cq_handle;
    cq->mq.index = be32_to_cpu(reply->mq_index);

    peer_pa = c2dev->pa + be32_to_cpu(reply->adapter_shared);
    cq->mq.peer = ioremap_nocache(peer_pa, PAGE_SIZE);
    if (!cq->mq.peer) {
        err = -ENOMEM;
        goto bail3;
    }

    vq_repbuf_free(c2dev, reply);
    vq_req_free(c2dev, vq_req);

    spin_lock_init(&cq->lock);
    atomic_set(&cq->refcount, 1);
    init_waitqueue_head(&cq->wait);

    /*
     * Use the MQ index allocated by the adapter to
     * store the CQ in the qptr_array
     */
    cq->cqn = cq->mq.index;
    c2dev->qptr_array[cq->cqn] = cq;

    return 0;

      bail3:
    vq_repbuf_free(c2dev, reply);
      bail2:
    vq_req_free(c2dev, vq_req);
      bail1:
    c2_free_cq_buf(c2dev, &cq->mq);
      bail0:
    c2_free_mqsp(cq->mq.shared);

    return err;
}

void c2_free_cq(struct c2_dev *c2dev, struct c2_cq *cq)
{
    int err;
    struct c2_vq_req *vq_req;
    struct c2wr_cq_destroy_req wr;
    struct c2wr_cq_destroy_rep *reply;

    might_sleep();

    /* Clear CQ from the qptr array */
    spin_lock_irq(&c2dev->lock);
    c2dev->qptr_array[cq->mq.index] = NULL;
    atomic_dec(&cq->refcount);
    spin_unlock_irq(&c2dev->lock);

    wait_event(cq->wait, !atomic_read(&cq->refcount));

    vq_req = vq_req_alloc(c2dev);
    if (!vq_req) {
        goto bail0;
    }

    memset(&wr, 0, sizeof(wr));
    c2_wr_set_id(&wr, CCWR_CQ_DESTROY);
    wr.hdr.context = (unsigned long) vq_req;
    wr.rnic_handle = c2dev->adapter_handle;
    wr.cq_handle = cq->adapter_handle;

    vq_req_get(c2dev, vq_req);

    err = vq_send_wr(c2dev, (union c2wr *) & wr);
    if (err) {
        vq_req_put(c2dev, vq_req);
        goto bail1;
    }

    err = vq_wait_for_reply(c2dev, vq_req);
    if (err)
        goto bail1;

    reply = (struct c2wr_cq_destroy_rep *) (unsigned long) (vq_req->reply_msg);
    if (reply)
        vq_repbuf_free(c2dev, reply);
      bail1:
    vq_req_free(c2dev, vq_req);
      bail0:
    if (cq->is_kernel) {
        c2_free_cq_buf(c2dev, &cq->mq);
    }

    return;
}