drivers/infiniband/hw/qib/qib_ruc.c

   1 /*
   2  * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
   3  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/spinlock.h>
  35 #include <rdma/ib_smi.h>
  36
  37 #include "qib.h"
  38 #include "qib_mad.h"
  39
  40 /*
  41  * Switch to alternate path.
  42  * The QP s_lock should be held and interrupts disabled.
  43  */
  44 void qib_migrate_qp(struct rvt_qp *qp)
  45 {
  46         struct ib_event ev;
  47
  48         qp->s_mig_state = IB_MIG_MIGRATED;
  49         qp->remote_ah_attr = qp->alt_ah_attr;
  50         qp->port_num = rdma_ah_get_port_num(&qp->alt_ah_attr);
  51         qp->s_pkey_index = qp->s_alt_pkey_index;
  52
  53         ev.device = qp->ibqp.device;
  54         ev.element.qp = &qp->ibqp;
  55         ev.event = IB_EVENT_PATH_MIG;
  56         qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
  57 }
  58
  59 static __be64 get_sguid(struct qib_ibport *ibp, unsigned index)
  60 {
  61         if (!index) {
  62                 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
  63
  64                 return ppd->guid;
  65         }
  66         return ibp->guids[index - 1];
  67 }
  68
  69 static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
  70 {
  71         return (gid->global.interface_id == id &&
  72                 (gid->global.subnet_prefix == gid_prefix ||
  73                  gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
  74 }
  75
  76 /*
  77  *
  78  * This should be called with the QP r_lock held.
  79  *
  80  * The s_lock will be acquired around the qib_migrate_qp() call.
  81  */
  82 int qib_ruc_check_hdr(struct qib_ibport *ibp, struct ib_header *hdr,
  83                       int has_grh, struct rvt_qp *qp, u32 bth0)
  84 {
  85         __be64 guid;
  86         unsigned long flags;
  87
  88         if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
  89                 if (!has_grh) {
  90                         if (rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
  91                             IB_AH_GRH)
  92                                 goto err;
  93                 } else {
  94                         const struct ib_global_route *grh;
  95
  96                         if (!(rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
  97                               IB_AH_GRH))
  98                                 goto err;
  99                         grh = rdma_ah_read_grh(&qp->alt_ah_attr);
 100                         guid = get_sguid(ibp, grh->sgid_index);
 101                         if (!gid_ok(&hdr->u.l.grh.dgid,
 102                                     ibp->rvp.gid_prefix, guid))
 103                                 goto err;
 104                         if (!gid_ok(&hdr->u.l.grh.sgid,
 105                             grh->dgid.global.subnet_prefix,
 106                             grh->dgid.global.interface_id))
 107                                 goto err;
 108                 }
 109                 if (!qib_pkey_ok((u16)bth0,
 110                                  qib_get_pkey(ibp, qp->s_alt_pkey_index))) {
 111                         qib_bad_pkey(ibp,
 112                                      (u16)bth0,
 113                                      (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
 114                                      0, qp->ibqp.qp_num,
 115                                      hdr->lrh[3], hdr->lrh[1]);
 116                         goto err;
 117                 }
 118                 /* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
 119                 if ((be16_to_cpu(hdr->lrh[3]) !=
 120                      rdma_ah_get_dlid(&qp->alt_ah_attr)) ||
 121                     ppd_from_ibp(ibp)->port !=
 122                             rdma_ah_get_port_num(&qp->alt_ah_attr))
 123                         goto err;
 124                 spin_lock_irqsave(&qp->s_lock, flags);
 125                 qib_migrate_qp(qp);
 126                 spin_unlock_irqrestore(&qp->s_lock, flags);
 127         } else {
 128                 if (!has_grh) {
 129                         if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
 130                             IB_AH_GRH)
 131                                 goto err;
 132                 } else {
 133                         const struct ib_global_route *grh;
 134
 135                         if (!(rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
 136                               IB_AH_GRH))
 137                                 goto err;
 138                         grh = rdma_ah_read_grh(&qp->remote_ah_attr);
 139                         guid = get_sguid(ibp, grh->sgid_index);
 140                         if (!gid_ok(&hdr->u.l.grh.dgid,
 141                                     ibp->rvp.gid_prefix, guid))
 142                                 goto err;
 143                         if (!gid_ok(&hdr->u.l.grh.sgid,
 144                             grh->dgid.global.subnet_prefix,
 145                             grh->dgid.global.interface_id))
 146                                 goto err;
 147                 }
 148                 if (!qib_pkey_ok((u16)bth0,
 149                                  qib_get_pkey(ibp, qp->s_pkey_index))) {
 150                         qib_bad_pkey(ibp,
 151                                      (u16)bth0,
 152                                      (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
 153                                      0, qp->ibqp.qp_num,
 154                                      hdr->lrh[3], hdr->lrh[1]);
 155                         goto err;
 156                 }
 157                 /* Validate the SLID. See Ch. 9.6.1.5 */
 158                 if (be16_to_cpu(hdr->lrh[3]) !=
 159                     rdma_ah_get_dlid(&qp->remote_ah_attr) ||
 160                     ppd_from_ibp(ibp)->port != qp->port_num)
 161                         goto err;
 162                 if (qp->s_mig_state == IB_MIG_REARM &&
 163                     !(bth0 & IB_BTH_MIG_REQ))
 164                         qp->s_mig_state = IB_MIG_ARMED;
 165         }
 166
 167         return 0;
 168
 169 err:
 170         return 1;
 171 }
 172
 173 /**
 174  * qib_make_grh - construct a GRH header
 175  * @ibp: a pointer to the IB port
 176  * @hdr: a pointer to the GRH header being constructed
 177  * @grh: the global route address to send to
 178  * @hwords: the number of 32 bit words of header being sent
 179  * @nwords: the number of 32 bit words of data being sent
 180  *
 181  * Return the size of the header in 32 bit words.
 182  */
 183 u32 qib_make_grh(struct qib_ibport *ibp, struct ib_grh *hdr,
 184                  const struct ib_global_route *grh, u32 hwords, u32 nwords)
 185 {
 186         hdr->version_tclass_flow =
 187                 cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
 188                             (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
 189                             (grh->flow_label << IB_GRH_FLOW_SHIFT));
 190         hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
 191         /* next_hdr is defined by C8-7 in ch. 8.4.1 */
 192         hdr->next_hdr = IB_GRH_NEXT_HDR;
 193         hdr->hop_limit = grh->hop_limit;
 194         /* The SGID is 32-bit aligned. */
 195         hdr->sgid.global.subnet_prefix = ibp->rvp.gid_prefix;
 196         if (!grh->sgid_index)
 197                 hdr->sgid.global.interface_id = ppd_from_ibp(ibp)->guid;
 198         else if (grh->sgid_index < QIB_GUIDS_PER_PORT)
 199                 hdr->sgid.global.interface_id = ibp->guids[grh->sgid_index - 1];
 200         hdr->dgid = grh->dgid;
 201
 202         /* GRH header size in 32-bit words. */
 203         return sizeof(struct ib_grh) / sizeof(u32);
 204 }
 205
 206 void qib_make_ruc_header(struct rvt_qp *qp, struct ib_other_headers *ohdr,
 207                          u32 bth0, u32 bth2)
 208 {
 209         struct qib_qp_priv *priv = qp->priv;
 210         struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
 211         u16 lrh0;
 212         u32 nwords;
 213         u32 extra_bytes;
 214
 215         /* Construct the header. */
 216         extra_bytes = -qp->s_cur_size & 3;
 217         nwords = (qp->s_cur_size + extra_bytes) >> 2;
 218         lrh0 = QIB_LRH_BTH;
 219         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
 220                 qp->s_hdrwords +=
 221                         qib_make_grh(ibp, &priv->s_hdr->u.l.grh,
 222                                      rdma_ah_read_grh(&qp->remote_ah_attr),
 223                                      qp->s_hdrwords, nwords);
 224                 lrh0 = QIB_LRH_GRH;
 225         }
 226         lrh0 |= ibp->sl_to_vl[rdma_ah_get_sl(&qp->remote_ah_attr)] << 12 |
 227                 rdma_ah_get_sl(&qp->remote_ah_attr) << 4;
 228         priv->s_hdr->lrh[0] = cpu_to_be16(lrh0);
 229         priv->s_hdr->lrh[1] =
 230                         cpu_to_be16(rdma_ah_get_dlid(&qp->remote_ah_attr));
 231         priv->s_hdr->lrh[2] =
 232                         cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
 233         priv->s_hdr->lrh[3] =
 234                 cpu_to_be16(ppd_from_ibp(ibp)->lid |
 235                             rdma_ah_get_path_bits(&qp->remote_ah_attr));
 236         bth0 |= qib_get_pkey(ibp, qp->s_pkey_index);
 237         bth0 |= extra_bytes << 20;
 238         if (qp->s_mig_state == IB_MIG_MIGRATED)
 239                 bth0 |= IB_BTH_MIG_REQ;
 240         ohdr->bth[0] = cpu_to_be32(bth0);
 241         ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
 242         ohdr->bth[2] = cpu_to_be32(bth2);
 243         this_cpu_inc(ibp->pmastats->n_unicast_xmit);
 244 }
 245
 246 void _qib_do_send(struct work_struct *work)
 247 {
 248         struct qib_qp_priv *priv = container_of(work, struct qib_qp_priv,
 249                                                 s_work);
 250         struct rvt_qp *qp = priv->owner;
 251
 252         qib_do_send(qp);
 253 }
 254
 255 /**
 256  * qib_do_send - perform a send on a QP
 257  * @qp: pointer to the QP
 258  *
 259  * Process entries in the send work queue until credit or queue is
 260  * exhausted.  Only allow one CPU to send a packet per QP (tasklet).
 261  * Otherwise, two threads could send packets out of order.
 262  */
 263 void qib_do_send(struct rvt_qp *qp)
 264 {
 265         struct qib_qp_priv *priv = qp->priv;
 266         struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
 267         struct qib_pportdata *ppd = ppd_from_ibp(ibp);
 268         int (*make_req)(struct rvt_qp *qp, unsigned long *flags);
 269         unsigned long flags;
 270
 271         if ((qp->ibqp.qp_type == IB_QPT_RC ||
 272              qp->ibqp.qp_type == IB_QPT_UC) &&
 273             (rdma_ah_get_dlid(&qp->remote_ah_attr) &
 274              ~((1 << ppd->lmc) - 1)) == ppd->lid) {
 275                 rvt_ruc_loopback(qp);
 276                 return;
 277         }
 278
 279         if (qp->ibqp.qp_type == IB_QPT_RC)
 280                 make_req = qib_make_rc_req;
 281         else if (qp->ibqp.qp_type == IB_QPT_UC)
 282                 make_req = qib_make_uc_req;
 283         else
 284                 make_req = qib_make_ud_req;
 285
 286         spin_lock_irqsave(&qp->s_lock, flags);
 287
 288         /* Return if we are already busy processing a work request. */
 289         if (!qib_send_ok(qp)) {
 290                 spin_unlock_irqrestore(&qp->s_lock, flags);
 291                 return;
 292         }
 293
 294         qp->s_flags |= RVT_S_BUSY;
 295
 296         do {
 297                 /* Check for a constructed packet to be sent. */
 298                 if (qp->s_hdrwords != 0) {
 299                         spin_unlock_irqrestore(&qp->s_lock, flags);
 300                         /*
 301                          * If the packet cannot be sent now, return and
 302                          * the send tasklet will be woken up later.
 303                          */
 304                         if (qib_verbs_send(qp, priv->s_hdr, qp->s_hdrwords,
 305                                            qp->s_cur_sge, qp->s_cur_size))
 306                                 return;
 307                         /* Record that s_hdr is empty. */
 308                         qp->s_hdrwords = 0;
 309                         spin_lock_irqsave(&qp->s_lock, flags);
 310                 }
 311         } while (make_req(qp, &flags));
 312
 313         spin_unlock_irqrestore(&qp->s_lock, flags);
 314 }