mthca_mad.c

Go to the documentation of this file.

/*
 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
 * Copyright (c) 2004 Voltaire, 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/string.h>
#include <linux/slab.h>

#include <rdma/ib_verbs.h>
#include <rdma/ib_mad.h>
#include <rdma/ib_smi.h>

#include "mthca_dev.h"
#include "mthca_cmd.h"

enum {
    MTHCA_VENDOR_CLASS1 = 0x9,
    MTHCA_VENDOR_CLASS2 = 0xa
};

static int mthca_update_rate(struct mthca_dev *dev, u8 port_num)
{
    struct ib_port_attr *tprops = NULL;
    int                  ret;

    tprops = kmalloc(sizeof *tprops, GFP_KERNEL);
    if (!tprops)
        return -ENOMEM;

    ret = ib_query_port(&dev->ib_dev, port_num, tprops);
    if (ret) {
        printk(KERN_WARNING "ib_query_port failed (%d) for %s port %d\n",
               ret, dev->ib_dev.name, port_num);
        goto out;
    }

    dev->rate[port_num - 1] = tprops->active_speed *
                  ib_width_enum_to_int(tprops->active_width);

out:
    kfree(tprops);
    return ret;
}

static void update_sm_ah(struct mthca_dev *dev,
             u8 port_num, u16 lid, u8 sl)
{
    struct ib_ah *new_ah;
    struct ib_ah_attr ah_attr;
    unsigned long flags;

    if (!dev->send_agent[port_num - 1][0])
        return;

    memset(&ah_attr, 0, sizeof ah_attr);
    ah_attr.dlid     = lid;
    ah_attr.sl       = sl;
    ah_attr.port_num = port_num;

    new_ah = ib_create_ah(dev->send_agent[port_num - 1][0]->qp->pd,
                  &ah_attr);
    if (IS_ERR(new_ah))
        return;

    spin_lock_irqsave(&dev->sm_lock, flags);
    if (dev->sm_ah[port_num - 1])
        ib_destroy_ah(dev->sm_ah[port_num - 1]);
    dev->sm_ah[port_num - 1] = new_ah;
    spin_unlock_irqrestore(&dev->sm_lock, flags);
}

/*
 * Snoop SM MADs for port info and P_Key table sets, so we can
 * synthesize LID change and P_Key change events.
 */
static void smp_snoop(struct ib_device *ibdev,
              u8 port_num,
              struct ib_mad *mad,
              u16 prev_lid)
{
    struct ib_event event;

    if ((mad->mad_hdr.mgmt_class  == IB_MGMT_CLASS_SUBN_LID_ROUTED ||
         mad->mad_hdr.mgmt_class  == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) &&
        mad->mad_hdr.method     == IB_MGMT_METHOD_SET) {
        if (mad->mad_hdr.attr_id == IB_SMP_ATTR_PORT_INFO) {
            struct ib_port_info *pinfo =
                (struct ib_port_info *) ((struct ib_smp *) mad)->data;
            u16 lid = be16_to_cpu(pinfo->lid);

            mthca_update_rate(to_mdev(ibdev), port_num);
            update_sm_ah(to_mdev(ibdev), port_num,
                     be16_to_cpu(pinfo->sm_lid),
                     pinfo->neighbormtu_mastersmsl & 0xf);

            event.device           = ibdev;
            event.element.port_num = port_num;

            if (pinfo->clientrereg_resv_subnetto & 0x80) {
                event.event    = IB_EVENT_CLIENT_REREGISTER;
                ib_dispatch_event(&event);
            }

            if (prev_lid != lid) {
                event.event    = IB_EVENT_LID_CHANGE;
                ib_dispatch_event(&event);
            }
        }

        if (mad->mad_hdr.attr_id == IB_SMP_ATTR_PKEY_TABLE) {
            event.device           = ibdev;
            event.event            = IB_EVENT_PKEY_CHANGE;
            event.element.port_num = port_num;
            ib_dispatch_event(&event);
        }
    }
}

static void node_desc_override(struct ib_device *dev,
                   struct ib_mad *mad)
{
    if ((mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_LID_ROUTED ||
         mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) &&
        mad->mad_hdr.method == IB_MGMT_METHOD_GET_RESP &&
        mad->mad_hdr.attr_id == IB_SMP_ATTR_NODE_DESC) {
        mutex_lock(&to_mdev(dev)->cap_mask_mutex);
        memcpy(((struct ib_smp *) mad)->data, dev->node_desc, 64);
        mutex_unlock(&to_mdev(dev)->cap_mask_mutex);
    }
}

static void forward_trap(struct mthca_dev *dev,
             u8 port_num,
             struct ib_mad *mad)
{
    int qpn = mad->mad_hdr.mgmt_class != IB_MGMT_CLASS_SUBN_LID_ROUTED;
    struct ib_mad_send_buf *send_buf;
    struct ib_mad_agent *agent = dev->send_agent[port_num - 1][qpn];
    int ret;
    unsigned long flags;

    if (agent) {
        send_buf = ib_create_send_mad(agent, qpn, 0, 0, IB_MGMT_MAD_HDR,
                          IB_MGMT_MAD_DATA, GFP_ATOMIC);
        if (IS_ERR(send_buf))
            return;
        /*
         * We rely here on the fact that MLX QPs don't use the
         * address handle after the send is posted (this is
         * wrong following the IB spec strictly, but we know
         * it's OK for our devices).
         */
        spin_lock_irqsave(&dev->sm_lock, flags);
        memcpy(send_buf->mad, mad, sizeof *mad);
        if ((send_buf->ah = dev->sm_ah[port_num - 1]))
            ret = ib_post_send_mad(send_buf, NULL);
        else
            ret = -EINVAL;
        spin_unlock_irqrestore(&dev->sm_lock, flags);

        if (ret)
            ib_free_send_mad(send_buf);
    }
}

int mthca_process_mad(struct ib_device *ibdev,
              int mad_flags,
              u8 port_num,
              struct ib_wc *in_wc,
              struct ib_grh *in_grh,
              struct ib_mad *in_mad,
              struct ib_mad *out_mad)
{
    int err;
    u16 slid = in_wc ? in_wc->slid : be16_to_cpu(IB_LID_PERMISSIVE);
    u16 prev_lid = 0;
    struct ib_port_attr pattr;

    /* Forward locally generated traps to the SM */
    if (in_mad->mad_hdr.method == IB_MGMT_METHOD_TRAP &&
        slid == 0) {
        forward_trap(to_mdev(ibdev), port_num, in_mad);
        return IB_MAD_RESULT_SUCCESS | IB_MAD_RESULT_CONSUMED;
    }

    /*
     * Only handle SM gets, sets and trap represses for SM class
     *
     * Only handle PMA and Mellanox vendor-specific class gets and
     * sets for other classes.
     */
    if (in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_LID_ROUTED ||
        in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) {
        if (in_mad->mad_hdr.method   != IB_MGMT_METHOD_GET &&
            in_mad->mad_hdr.method   != IB_MGMT_METHOD_SET &&
            in_mad->mad_hdr.method   != IB_MGMT_METHOD_TRAP_REPRESS)
            return IB_MAD_RESULT_SUCCESS;

        /*
         * Don't process SMInfo queries or vendor-specific
         * MADs -- the SMA can't handle them.
         */
        if (in_mad->mad_hdr.attr_id == IB_SMP_ATTR_SM_INFO ||
            ((in_mad->mad_hdr.attr_id & IB_SMP_ATTR_VENDOR_MASK) ==
             IB_SMP_ATTR_VENDOR_MASK))
            return IB_MAD_RESULT_SUCCESS;
    } else if (in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_PERF_MGMT ||
           in_mad->mad_hdr.mgmt_class == MTHCA_VENDOR_CLASS1     ||
           in_mad->mad_hdr.mgmt_class == MTHCA_VENDOR_CLASS2) {
        if (in_mad->mad_hdr.method  != IB_MGMT_METHOD_GET &&
            in_mad->mad_hdr.method  != IB_MGMT_METHOD_SET)
            return IB_MAD_RESULT_SUCCESS;
    } else
        return IB_MAD_RESULT_SUCCESS;
    if ((in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_LID_ROUTED ||
         in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) &&
        in_mad->mad_hdr.method == IB_MGMT_METHOD_SET &&
        in_mad->mad_hdr.attr_id == IB_SMP_ATTR_PORT_INFO &&
        !ib_query_port(ibdev, port_num, &pattr))
        prev_lid = pattr.lid;

    err = mthca_MAD_IFC(to_mdev(ibdev),
                mad_flags & IB_MAD_IGNORE_MKEY,
                mad_flags & IB_MAD_IGNORE_BKEY,
                port_num, in_wc, in_grh, in_mad, out_mad);
    if (err == -EBADMSG)
        return IB_MAD_RESULT_SUCCESS;
    else if (err) {
        mthca_err(to_mdev(ibdev), "MAD_IFC returned %d\n", err);
        return IB_MAD_RESULT_FAILURE;
    }

    if (!out_mad->mad_hdr.status) {
        smp_snoop(ibdev, port_num, in_mad, prev_lid);
        node_desc_override(ibdev, out_mad);
    }

    /* set return bit in status of directed route responses */
    if (in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE)
        out_mad->mad_hdr.status |= cpu_to_be16(1 << 15);

    if (in_mad->mad_hdr.method == IB_MGMT_METHOD_TRAP_REPRESS)
        /* no response for trap repress */
        return IB_MAD_RESULT_SUCCESS | IB_MAD_RESULT_CONSUMED;

    return IB_MAD_RESULT_SUCCESS | IB_MAD_RESULT_REPLY;
}

static void send_handler(struct ib_mad_agent *agent,
             struct ib_mad_send_wc *mad_send_wc)
{
    ib_free_send_mad(mad_send_wc->send_buf);
}

int mthca_create_agents(struct mthca_dev *dev)
{
    struct ib_mad_agent *agent;
    int p, q;
    int ret;

    spin_lock_init(&dev->sm_lock);

    for (p = 0; p < dev->limits.num_ports; ++p)
        for (q = 0; q <= 1; ++q) {
            agent = ib_register_mad_agent(&dev->ib_dev, p + 1,
                              q ? IB_QPT_GSI : IB_QPT_SMI,
                              NULL, 0, send_handler,
                              NULL, NULL);
            if (IS_ERR(agent)) {
                ret = PTR_ERR(agent);
                goto err;
            }
            dev->send_agent[p][q] = agent;
        }


    for (p = 1; p <= dev->limits.num_ports; ++p) {
        ret = mthca_update_rate(dev, p);
        if (ret) {
            mthca_err(dev, "Failed to obtain port %d rate."
                  " aborting.\n", p);
            goto err;
        }
    }

    return 0;

err:
    for (p = 0; p < dev->limits.num_ports; ++p)
        for (q = 0; q <= 1; ++q)
            if (dev->send_agent[p][q])
                ib_unregister_mad_agent(dev->send_agent[p][q]);

    return ret;
}

void mthca_free_agents(struct mthca_dev *dev)
{
    struct ib_mad_agent *agent;
    int p, q;

    for (p = 0; p < dev->limits.num_ports; ++p) {
        for (q = 0; q <= 1; ++q) {
            agent = dev->send_agent[p][q];
            dev->send_agent[p][q] = NULL;
            ib_unregister_mad_agent(agent);
        }

        if (dev->sm_ah[p])
            ib_destroy_ah(dev->sm_ah[p]);
    }
}