hw/qib/qib_ruc.c

0001 /*
0002  * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
0003  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
0004  *
0005  * This software is available to you under a choice of one of two
0006  * licenses.  You may choose to be licensed under the terms of the GNU
0007  * General Public License (GPL) Version 2, available from the file
0008  * COPYING in the main directory of this source tree, or the
0009  * OpenIB.org BSD license below:
0010  *
0011  *     Redistribution and use in source and binary forms, with or
0012  *     without modification, are permitted provided that the following
0013  *     conditions are met:
0014  *
0015  *      - Redistributions of source code must retain the above
0016  *        copyright notice, this list of conditions and the following
0017  *        disclaimer.
0018  *
0019  *      - Redistributions in binary form must reproduce the above
0020  *        copyright notice, this list of conditions and the following
0021  *        disclaimer in the documentation and/or other materials
0022  *        provided with the distribution.
0023  *
0024  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
0025  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
0026  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
0027  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
0028  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
0029  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
0030  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
0031  * SOFTWARE.
0032  */
0033
0034 #include <linux/spinlock.h>
0035 #include <rdma/ib_smi.h>
0036
0037 #include "qib.h"
0038 #include "qib_mad.h"
0039
0040 /*
0041  * Switch to alternate path.
0042  * The QP s_lock should be held and interrupts disabled.
0043  */
0044 void qib_migrate_qp(struct rvt_qp *qp)
0045 {
0046     struct ib_event ev;
0047
0048     qp->s_mig_state = IB_MIG_MIGRATED;
0049     qp->remote_ah_attr = qp->alt_ah_attr;
0050     qp->port_num = rdma_ah_get_port_num(&qp->alt_ah_attr);
0051     qp->s_pkey_index = qp->s_alt_pkey_index;
0052
0053     ev.device = qp->ibqp.device;
0054     ev.element.qp = &qp->ibqp;
0055     ev.event = IB_EVENT_PATH_MIG;
0056     qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
0057 }
0058
0059 static __be64 get_sguid(struct qib_ibport *ibp, unsigned index)
0060 {
0061     if (!index) {
0062         struct qib_pportdata *ppd = ppd_from_ibp(ibp);
0063
0064         return ppd->guid;
0065     }
0066     return ibp->guids[index - 1];
0067 }
0068
0069 static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
0070 {
0071     return (gid->global.interface_id == id &&
0072         (gid->global.subnet_prefix == gid_prefix ||
0073          gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
0074 }
0075
0076 /*
0077  *
0078  * This should be called with the QP r_lock held.
0079  *
0080  * The s_lock will be acquired around the qib_migrate_qp() call.
0081  */
0082 int qib_ruc_check_hdr(struct qib_ibport *ibp, struct ib_header *hdr,
0083               int has_grh, struct rvt_qp *qp, u32 bth0)
0084 {
0085     __be64 guid;
0086     unsigned long flags;
0087
0088     if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
0089         if (!has_grh) {
0090             if (rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
0091                 IB_AH_GRH)
0092                 goto err;
0093         } else {
0094             const struct ib_global_route *grh;
0095
0096             if (!(rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
0097                   IB_AH_GRH))
0098                 goto err;
0099             grh = rdma_ah_read_grh(&qp->alt_ah_attr);
0100             guid = get_sguid(ibp, grh->sgid_index);
0101             if (!gid_ok(&hdr->u.l.grh.dgid,
0102                     ibp->rvp.gid_prefix, guid))
0103                 goto err;
0104             if (!gid_ok(&hdr->u.l.grh.sgid,
0105                 grh->dgid.global.subnet_prefix,
0106                 grh->dgid.global.interface_id))
0107                 goto err;
0108         }
0109         if (!qib_pkey_ok((u16)bth0,
0110                  qib_get_pkey(ibp, qp->s_alt_pkey_index))) {
0111             qib_bad_pkey(ibp,
0112                      (u16)bth0,
0113                      (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
0114                      0, qp->ibqp.qp_num,
0115                      hdr->lrh[3], hdr->lrh[1]);
0116             goto err;
0117         }
0118         /* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
0119         if ((be16_to_cpu(hdr->lrh[3]) !=
0120              rdma_ah_get_dlid(&qp->alt_ah_attr)) ||
0121             ppd_from_ibp(ibp)->port !=
0122                 rdma_ah_get_port_num(&qp->alt_ah_attr))
0123             goto err;
0124         spin_lock_irqsave(&qp->s_lock, flags);
0125         qib_migrate_qp(qp);
0126         spin_unlock_irqrestore(&qp->s_lock, flags);
0127     } else {
0128         if (!has_grh) {
0129             if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
0130                 IB_AH_GRH)
0131                 goto err;
0132         } else {
0133             const struct ib_global_route *grh;
0134
0135             if (!(rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
0136                   IB_AH_GRH))
0137                 goto err;
0138             grh = rdma_ah_read_grh(&qp->remote_ah_attr);
0139             guid = get_sguid(ibp, grh->sgid_index);
0140             if (!gid_ok(&hdr->u.l.grh.dgid,
0141                     ibp->rvp.gid_prefix, guid))
0142                 goto err;
0143             if (!gid_ok(&hdr->u.l.grh.sgid,
0144                 grh->dgid.global.subnet_prefix,
0145                 grh->dgid.global.interface_id))
0146                 goto err;
0147         }
0148         if (!qib_pkey_ok((u16)bth0,
0149                  qib_get_pkey(ibp, qp->s_pkey_index))) {
0150             qib_bad_pkey(ibp,
0151                      (u16)bth0,
0152                      (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
0153                      0, qp->ibqp.qp_num,
0154                      hdr->lrh[3], hdr->lrh[1]);
0155             goto err;
0156         }
0157         /* Validate the SLID. See Ch. 9.6.1.5 */
0158         if (be16_to_cpu(hdr->lrh[3]) !=
0159             rdma_ah_get_dlid(&qp->remote_ah_attr) ||
0160             ppd_from_ibp(ibp)->port != qp->port_num)
0161             goto err;
0162         if (qp->s_mig_state == IB_MIG_REARM &&
0163             !(bth0 & IB_BTH_MIG_REQ))
0164             qp->s_mig_state = IB_MIG_ARMED;
0165     }
0166
0167     return 0;
0168
0169 err:
0170     return 1;
0171 }
0172
0173 /**
0174  * qib_make_grh - construct a GRH header
0175  * @ibp: a pointer to the IB port
0176  * @hdr: a pointer to the GRH header being constructed
0177  * @grh: the global route address to send to
0178  * @hwords: the number of 32 bit words of header being sent
0179  * @nwords: the number of 32 bit words of data being sent
0180  *
0181  * Return the size of the header in 32 bit words.
0182  */
0183 u32 qib_make_grh(struct qib_ibport *ibp, struct ib_grh *hdr,
0184          const struct ib_global_route *grh, u32 hwords, u32 nwords)
0185 {
0186     hdr->version_tclass_flow =
0187         cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
0188                 (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
0189                 (grh->flow_label << IB_GRH_FLOW_SHIFT));
0190     hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
0191     /* next_hdr is defined by C8-7 in ch. 8.4.1 */
0192     hdr->next_hdr = IB_GRH_NEXT_HDR;
0193     hdr->hop_limit = grh->hop_limit;
0194     /* The SGID is 32-bit aligned. */
0195     hdr->sgid.global.subnet_prefix = ibp->rvp.gid_prefix;
0196     if (!grh->sgid_index)
0197         hdr->sgid.global.interface_id = ppd_from_ibp(ibp)->guid;
0198     else if (grh->sgid_index < QIB_GUIDS_PER_PORT)
0199         hdr->sgid.global.interface_id = ibp->guids[grh->sgid_index - 1];
0200     hdr->dgid = grh->dgid;
0201
0202     /* GRH header size in 32-bit words. */
0203     return sizeof(struct ib_grh) / sizeof(u32);
0204 }
0205
0206 void qib_make_ruc_header(struct rvt_qp *qp, struct ib_other_headers *ohdr,
0207              u32 bth0, u32 bth2)
0208 {
0209     struct qib_qp_priv *priv = qp->priv;
0210     struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
0211     u16 lrh0;
0212     u32 nwords;
0213     u32 extra_bytes;
0214
0215     /* Construct the header. */
0216     extra_bytes = -qp->s_cur_size & 3;
0217     nwords = (qp->s_cur_size + extra_bytes) >> 2;
0218     lrh0 = QIB_LRH_BTH;
0219     if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
0220         qp->s_hdrwords +=
0221             qib_make_grh(ibp, &priv->s_hdr->u.l.grh,
0222                      rdma_ah_read_grh(&qp->remote_ah_attr),
0223                      qp->s_hdrwords, nwords);
0224         lrh0 = QIB_LRH_GRH;
0225     }
0226     lrh0 |= ibp->sl_to_vl[rdma_ah_get_sl(&qp->remote_ah_attr)] << 12 |
0227         rdma_ah_get_sl(&qp->remote_ah_attr) << 4;
0228     priv->s_hdr->lrh[0] = cpu_to_be16(lrh0);
0229     priv->s_hdr->lrh[1] =
0230             cpu_to_be16(rdma_ah_get_dlid(&qp->remote_ah_attr));
0231     priv->s_hdr->lrh[2] =
0232             cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
0233     priv->s_hdr->lrh[3] =
0234         cpu_to_be16(ppd_from_ibp(ibp)->lid |
0235                 rdma_ah_get_path_bits(&qp->remote_ah_attr));
0236     bth0 |= qib_get_pkey(ibp, qp->s_pkey_index);
0237     bth0 |= extra_bytes << 20;
0238     if (qp->s_mig_state == IB_MIG_MIGRATED)
0239         bth0 |= IB_BTH_MIG_REQ;
0240     ohdr->bth[0] = cpu_to_be32(bth0);
0241     ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
0242     ohdr->bth[2] = cpu_to_be32(bth2);
0243     this_cpu_inc(ibp->pmastats->n_unicast_xmit);
0244 }
0245
0246 void _qib_do_send(struct work_struct *work)
0247 {
0248     struct qib_qp_priv *priv = container_of(work, struct qib_qp_priv,
0249                         s_work);
0250     struct rvt_qp *qp = priv->owner;
0251
0252     qib_do_send(qp);
0253 }
0254
0255 /**
0256  * qib_do_send - perform a send on a QP
0257  * @qp: pointer to the QP
0258  *
0259  * Process entries in the send work queue until credit or queue is
0260  * exhausted.  Only allow one CPU to send a packet per QP (tasklet).
0261  * Otherwise, two threads could send packets out of order.
0262  */
0263 void qib_do_send(struct rvt_qp *qp)
0264 {
0265     struct qib_qp_priv *priv = qp->priv;
0266     struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
0267     struct qib_pportdata *ppd = ppd_from_ibp(ibp);
0268     int (*make_req)(struct rvt_qp *qp, unsigned long *flags);
0269     unsigned long flags;
0270
0271     if ((qp->ibqp.qp_type == IB_QPT_RC ||
0272          qp->ibqp.qp_type == IB_QPT_UC) &&
0273         (rdma_ah_get_dlid(&qp->remote_ah_attr) &
0274          ~((1 << ppd->lmc) - 1)) == ppd->lid) {
0275         rvt_ruc_loopback(qp);
0276         return;
0277     }
0278
0279     if (qp->ibqp.qp_type == IB_QPT_RC)
0280         make_req = qib_make_rc_req;
0281     else if (qp->ibqp.qp_type == IB_QPT_UC)
0282         make_req = qib_make_uc_req;
0283     else
0284         make_req = qib_make_ud_req;
0285
0286     spin_lock_irqsave(&qp->s_lock, flags);
0287
0288     /* Return if we are already busy processing a work request. */
0289     if (!qib_send_ok(qp)) {
0290         spin_unlock_irqrestore(&qp->s_lock, flags);
0291         return;
0292     }
0293
0294     qp->s_flags |= RVT_S_BUSY;
0295
0296     do {
0297         /* Check for a constructed packet to be sent. */
0298         if (qp->s_hdrwords != 0) {
0299             spin_unlock_irqrestore(&qp->s_lock, flags);
0300             /*
0301              * If the packet cannot be sent now, return and
0302              * the send tasklet will be woken up later.
0303              */
0304             if (qib_verbs_send(qp, priv->s_hdr, qp->s_hdrwords,
0305                        qp->s_cur_sge, qp->s_cur_size))
0306                 return;
0307             /* Record that s_hdr is empty. */
0308             qp->s_hdrwords = 0;
0309             spin_lock_irqsave(&qp->s_lock, flags);
0310         }
0311     } while (make_req(qp, &flags));
0312
0313     spin_unlock_irqrestore(&qp->s_lock, flags);
0314 }