kernel/drivers/infiniband/hw/qib/qib_srq.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/err.h>
  35 #include <linux/slab.h>
  36 #include <linux/vmalloc.h>
  37
  38 #include "qib_verbs.h"
  39
  40 /**
  41  * qib_post_srq_receive - post a receive on a shared receive queue
  42  * @ibsrq: the SRQ to post the receive on
  43  * @wr: the list of work requests to post
  44  * @bad_wr: A pointer to the first WR to cause a problem is put here
  45  *
  46  * This may be called from interrupt context.
  47  */
  48 int qib_post_srq_receive(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
  49                          struct ib_recv_wr **bad_wr)
  50 {
  51         struct qib_srq *srq = to_isrq(ibsrq);
  52         struct qib_rwq *wq;
  53         unsigned long flags;
  54         int ret;
  55
  56         for (; wr; wr = wr->next) {
  57                 struct qib_rwqe *wqe;
  58                 u32 next;
  59                 int i;
  60
  61                 if ((unsigned) wr->num_sge > srq->rq.max_sge) {
  62                         *bad_wr = wr;
  63                         ret = -EINVAL;
  64                         goto bail;
  65                 }
  66
  67                 spin_lock_irqsave(&srq->rq.lock, flags);
  68                 wq = srq->rq.wq;
  69                 next = wq->head + 1;
  70                 if (next >= srq->rq.size)
  71                         next = 0;
  72                 if (next == wq->tail) {
  73                         spin_unlock_irqrestore(&srq->rq.lock, flags);
  74                         *bad_wr = wr;
  75                         ret = -ENOMEM;
  76                         goto bail;
  77                 }
  78
  79                 wqe = get_rwqe_ptr(&srq->rq, wq->head);
  80                 wqe->wr_id = wr->wr_id;
  81                 wqe->num_sge = wr->num_sge;
  82                 for (i = 0; i < wr->num_sge; i++)
  83                         wqe->sg_list[i] = wr->sg_list[i];
  84                 /* Make sure queue entry is written before the head index. */
  85                 smp_wmb();
  86                 wq->head = next;
  87                 spin_unlock_irqrestore(&srq->rq.lock, flags);
  88         }
  89         ret = 0;
  90
  91 bail:
  92         return ret;
  93 }
  94
  95 /**
  96  * qib_create_srq - create a shared receive queue
  97  * @ibpd: the protection domain of the SRQ to create
  98  * @srq_init_attr: the attributes of the SRQ
  99  * @udata: data from libibverbs when creating a user SRQ
 100  */
 101 struct ib_srq *qib_create_srq(struct ib_pd *ibpd,
 102                               struct ib_srq_init_attr *srq_init_attr,
 103                               struct ib_udata *udata)
 104 {
 105         struct qib_ibdev *dev = to_idev(ibpd->device);
 106         struct qib_srq *srq;
 107         u32 sz;
 108         struct ib_srq *ret;
 109
 110         if (srq_init_attr->srq_type != IB_SRQT_BASIC) {
 111                 ret = ERR_PTR(-ENOSYS);
 112                 goto done;
 113         }
 114
 115         if (srq_init_attr->attr.max_sge == 0 ||
 116             srq_init_attr->attr.max_sge > ib_qib_max_srq_sges ||
 117             srq_init_attr->attr.max_wr == 0 ||
 118             srq_init_attr->attr.max_wr > ib_qib_max_srq_wrs) {
 119                 ret = ERR_PTR(-EINVAL);
 120                 goto done;
 121         }
 122
 123         srq = kmalloc(sizeof(*srq), GFP_KERNEL);
 124         if (!srq) {
 125                 ret = ERR_PTR(-ENOMEM);
 126                 goto done;
 127         }
 128
 129         /*
 130          * Need to use vmalloc() if we want to support large #s of entries.
 131          */
 132         srq->rq.size = srq_init_attr->attr.max_wr + 1;
 133         srq->rq.max_sge = srq_init_attr->attr.max_sge;
 134         sz = sizeof(struct ib_sge) * srq->rq.max_sge +
 135                 sizeof(struct qib_rwqe);
 136         srq->rq.wq = vmalloc_user(sizeof(struct qib_rwq) + srq->rq.size * sz);
 137         if (!srq->rq.wq) {
 138                 ret = ERR_PTR(-ENOMEM);
 139                 goto bail_srq;
 140         }
 141
 142         /*
 143          * Return the address of the RWQ as the offset to mmap.
 144          * See qib_mmap() for details.
 145          */
 146         if (udata && udata->outlen >= sizeof(__u64)) {
 147                 int err;
 148                 u32 s = sizeof(struct qib_rwq) + srq->rq.size * sz;
 149
 150                 srq->ip =
 151                     qib_create_mmap_info(dev, s, ibpd->uobject->context,
 152                                          srq->rq.wq);
 153                 if (!srq->ip) {
 154                         ret = ERR_PTR(-ENOMEM);
 155                         goto bail_wq;
 156                 }
 157
 158                 err = ib_copy_to_udata(udata, &srq->ip->offset,
 159                                        sizeof(srq->ip->offset));
 160                 if (err) {
 161                         ret = ERR_PTR(err);
 162                         goto bail_ip;
 163                 }
 164         } else
 165                 srq->ip = NULL;
 166
 167         /*
 168          * ib_create_srq() will initialize srq->ibsrq.
 169          */
 170         spin_lock_init(&srq->rq.lock);
 171         srq->rq.wq->head = 0;
 172         srq->rq.wq->tail = 0;
 173         srq->limit = srq_init_attr->attr.srq_limit;
 174
 175         spin_lock(&dev->n_srqs_lock);
 176         if (dev->n_srqs_allocated == ib_qib_max_srqs) {
 177                 spin_unlock(&dev->n_srqs_lock);
 178                 ret = ERR_PTR(-ENOMEM);
 179                 goto bail_ip;
 180         }
 181
 182         dev->n_srqs_allocated++;
 183         spin_unlock(&dev->n_srqs_lock);
 184
 185         if (srq->ip) {
 186                 spin_lock_irq(&dev->pending_lock);
 187                 list_add(&srq->ip->pending_mmaps, &dev->pending_mmaps);
 188                 spin_unlock_irq(&dev->pending_lock);
 189         }
 190
 191         ret = &srq->ibsrq;
 192         goto done;
 193
 194 bail_ip:
 195         kfree(srq->ip);
 196 bail_wq:
 197         vfree(srq->rq.wq);
 198 bail_srq:
 199         kfree(srq);
 200 done:
 201         return ret;
 202 }
 203
 204 /**
 205  * qib_modify_srq - modify a shared receive queue
 206  * @ibsrq: the SRQ to modify
 207  * @attr: the new attributes of the SRQ
 208  * @attr_mask: indicates which attributes to modify
 209  * @udata: user data for libibverbs.so
 210  */
 211 int qib_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
 212                    enum ib_srq_attr_mask attr_mask,
 213                    struct ib_udata *udata)
 214 {
 215         struct qib_srq *srq = to_isrq(ibsrq);
 216         struct qib_rwq *wq;
 217         int ret = 0;
 218
 219         if (attr_mask & IB_SRQ_MAX_WR) {
 220                 struct qib_rwq *owq;
 221                 struct qib_rwqe *p;
 222                 u32 sz, size, n, head, tail;
 223
 224                 /* Check that the requested sizes are below the limits. */
 225                 if ((attr->max_wr > ib_qib_max_srq_wrs) ||
 226                     ((attr_mask & IB_SRQ_LIMIT) ?
 227                      attr->srq_limit : srq->limit) > attr->max_wr) {
 228                         ret = -EINVAL;
 229                         goto bail;
 230                 }
 231
 232                 sz = sizeof(struct qib_rwqe) +
 233                         srq->rq.max_sge * sizeof(struct ib_sge);
 234                 size = attr->max_wr + 1;
 235                 wq = vmalloc_user(sizeof(struct qib_rwq) + size * sz);
 236                 if (!wq) {
 237                         ret = -ENOMEM;
 238                         goto bail;
 239                 }
 240
 241                 /* Check that we can write the offset to mmap. */
 242                 if (udata && udata->inlen >= sizeof(__u64)) {
 243                         __u64 offset_addr;
 244                         __u64 offset = 0;
 245
 246                         ret = ib_copy_from_udata(&offset_addr, udata,
 247                                                  sizeof(offset_addr));
 248                         if (ret)
 249                                 goto bail_free;
 250                         udata->outbuf =
 251                                 (void __user *) (unsigned long) offset_addr;
 252                         ret = ib_copy_to_udata(udata, &offset,
 253                                                sizeof(offset));
 254                         if (ret)
 255                                 goto bail_free;
 256                 }
 257
 258                 spin_lock_irq(&srq->rq.lock);
 259                 /*
 260                  * validate head and tail pointer values and compute
 261                  * the number of remaining WQEs.
 262                  */
 263                 owq = srq->rq.wq;
 264                 head = owq->head;
 265                 tail = owq->tail;
 266                 if (head >= srq->rq.size || tail >= srq->rq.size) {
 267                         ret = -EINVAL;
 268                         goto bail_unlock;
 269                 }
 270                 n = head;
 271                 if (n < tail)
 272                         n += srq->rq.size - tail;
 273                 else
 274                         n -= tail;
 275                 if (size <= n) {
 276                         ret = -EINVAL;
 277                         goto bail_unlock;
 278                 }
 279                 n = 0;
 280                 p = wq->wq;
 281                 while (tail != head) {
 282                         struct qib_rwqe *wqe;
 283                         int i;
 284
 285                         wqe = get_rwqe_ptr(&srq->rq, tail);
 286                         p->wr_id = wqe->wr_id;
 287                         p->num_sge = wqe->num_sge;
 288                         for (i = 0; i < wqe->num_sge; i++)
 289                                 p->sg_list[i] = wqe->sg_list[i];
 290                         n++;
 291                         p = (struct qib_rwqe *)((char *) p + sz);
 292                         if (++tail >= srq->rq.size)
 293                                 tail = 0;
 294                 }
 295                 srq->rq.wq = wq;
 296                 srq->rq.size = size;
 297                 wq->head = n;
 298                 wq->tail = 0;
 299                 if (attr_mask & IB_SRQ_LIMIT)
 300                         srq->limit = attr->srq_limit;
 301                 spin_unlock_irq(&srq->rq.lock);
 302
 303                 vfree(owq);
 304
 305                 if (srq->ip) {
 306                         struct qib_mmap_info *ip = srq->ip;
 307                         struct qib_ibdev *dev = to_idev(srq->ibsrq.device);
 308                         u32 s = sizeof(struct qib_rwq) + size * sz;
 309
 310                         qib_update_mmap_info(dev, ip, s, wq);
 311
 312                         /*
 313                          * Return the offset to mmap.
 314                          * See qib_mmap() for details.
 315                          */
 316                         if (udata && udata->inlen >= sizeof(__u64)) {
 317                                 ret = ib_copy_to_udata(udata, &ip->offset,
 318                                                        sizeof(ip->offset));
 319                                 if (ret)
 320                                         goto bail;
 321                         }
 322
 323                         /*
 324                          * Put user mapping info onto the pending list
 325                          * unless it already is on the list.
 326                          */
 327                         spin_lock_irq(&dev->pending_lock);
 328                         if (list_empty(&ip->pending_mmaps))
 329                                 list_add(&ip->pending_mmaps,
 330                                          &dev->pending_mmaps);
 331                         spin_unlock_irq(&dev->pending_lock);
 332                 }
 333         } else if (attr_mask & IB_SRQ_LIMIT) {
 334                 spin_lock_irq(&srq->rq.lock);
 335                 if (attr->srq_limit >= srq->rq.size)
 336                         ret = -EINVAL;
 337                 else
 338                         srq->limit = attr->srq_limit;
 339                 spin_unlock_irq(&srq->rq.lock);
 340         }
 341         goto bail;
 342
 343 bail_unlock:
 344         spin_unlock_irq(&srq->rq.lock);
 345 bail_free:
 346         vfree(wq);
 347 bail:
 348         return ret;
 349 }
 350
 351 int qib_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr)
 352 {
 353         struct qib_srq *srq = to_isrq(ibsrq);
 354
 355         attr->max_wr = srq->rq.size - 1;
 356         attr->max_sge = srq->rq.max_sge;
 357         attr->srq_limit = srq->limit;
 358         return 0;
 359 }
 360
 361 /**
 362  * qib_destroy_srq - destroy a shared receive queue
 363  * @ibsrq: the SRQ to destroy
 364  */
 365 int qib_destroy_srq(struct ib_srq *ibsrq)
 366 {
 367         struct qib_srq *srq = to_isrq(ibsrq);
 368         struct qib_ibdev *dev = to_idev(ibsrq->device);
 369
 370         spin_lock(&dev->n_srqs_lock);
 371         dev->n_srqs_allocated--;
 372         spin_unlock(&dev->n_srqs_lock);
 373         if (srq->ip)
 374                 kref_put(&srq->ip->ref, qib_release_mmap_info);
 375         else
 376                 vfree(srq->rq.wq);
 377         kfree(srq);
 378
 379         return 0;
 380 }