drivers/infiniband/hw/ipath/ipath_srq.c

   1 /*
   2  * Copyright (c) 2006, 2007 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/vmalloc.h>
  36
  37 #include "ipath_verbs.h"
  38
  39 /**
  40  * ipath_post_srq_receive - post a receive on a shared receive queue
  41  * @ibsrq: the SRQ to post the receive on
  42  * @wr: the list of work requests to post
  43  * @bad_wr: the first WR to cause a problem is put here
  44  *
  45  * This may be called from interrupt context.
  46  */
  47 int ipath_post_srq_receive(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
  48                            struct ib_recv_wr **bad_wr)
  49 {
  50         struct ipath_srq *srq = to_isrq(ibsrq);
  51         struct ipath_rwq *wq;
  52         unsigned long flags;
  53         int ret;
  54
  55         for (; wr; wr = wr->next) {
  56                 struct ipath_rwqe *wqe;
  57                 u32 next;
  58                 int i;
  59
  60                 if ((unsigned) wr->num_sge > srq->rq.max_sge) {
  61                         *bad_wr = wr;
  62                         ret = -ENOMEM;
  63                         goto bail;
  64                 }
  65
  66                 spin_lock_irqsave(&srq->rq.lock, flags);
  67                 wq = srq->rq.wq;
  68                 next = wq->head + 1;
  69                 if (next >= srq->rq.size)
  70                         next = 0;
  71                 if (next == wq->tail) {
  72                         spin_unlock_irqrestore(&srq->rq.lock, flags);
  73                         *bad_wr = wr;
  74                         ret = -ENOMEM;
  75                         goto bail;
  76                 }
  77
  78                 wqe = get_rwqe_ptr(&srq->rq, wq->head);
  79                 wqe->wr_id = wr->wr_id;
  80                 wqe->num_sge = wr->num_sge;
  81                 for (i = 0; i < wr->num_sge; i++)
  82                         wqe->sg_list[i] = wr->sg_list[i];
  83                 /* Make sure queue entry is written before the head index. */
  84                 smp_wmb();
  85                 wq->head = next;
  86                 spin_unlock_irqrestore(&srq->rq.lock, flags);
  87         }
  88         ret = 0;
  89
  90 bail:
  91         return ret;
  92 }
  93
  94 /**
  95  * ipath_create_srq - create a shared receive queue
  96  * @ibpd: the protection domain of the SRQ to create
  97  * @attr: the attributes of the SRQ
  98  * @udata: not used by the InfiniPath verbs driver
  99  */
 100 struct ib_srq *ipath_create_srq(struct ib_pd *ibpd,
 101                                 struct ib_srq_init_attr *srq_init_attr,
 102                                 struct ib_udata *udata)
 103 {
 104         struct ipath_ibdev *dev = to_idev(ibpd->device);
 105         struct ipath_srq *srq;
 106         u32 sz;
 107         struct ib_srq *ret;
 108
 109         if (srq_init_attr->attr.max_wr == 0) {
 110                 ret = ERR_PTR(-EINVAL);
 111                 goto done;
 112         }
 113
 114         if ((srq_init_attr->attr.max_sge > ib_ipath_max_srq_sges) ||
 115             (srq_init_attr->attr.max_wr > ib_ipath_max_srq_wrs)) {
 116                 ret = ERR_PTR(-EINVAL);
 117                 goto done;
 118         }
 119
 120         srq = kmalloc(sizeof(*srq), GFP_KERNEL);
 121         if (!srq) {
 122                 ret = ERR_PTR(-ENOMEM);
 123                 goto done;
 124         }
 125
 126         /*
 127          * Need to use vmalloc() if we want to support large #s of entries.
 128          */
 129         srq->rq.size = srq_init_attr->attr.max_wr + 1;
 130         srq->rq.max_sge = srq_init_attr->attr.max_sge;
 131         sz = sizeof(struct ib_sge) * srq->rq.max_sge +
 132                 sizeof(struct ipath_rwqe);
 133         srq->rq.wq = vmalloc_user(sizeof(struct ipath_rwq) + srq->rq.size * sz);
 134         if (!srq->rq.wq) {
 135                 ret = ERR_PTR(-ENOMEM);
 136                 goto bail_srq;
 137         }
 138
 139         /*
 140          * Return the address of the RWQ as the offset to mmap.
 141          * See ipath_mmap() for details.
 142          */
 143         if (udata && udata->outlen >= sizeof(__u64)) {
 144                 int err;
 145                 u32 s = sizeof(struct ipath_rwq) + srq->rq.size * sz;
 146
 147                 srq->ip =
 148                     ipath_create_mmap_info(dev, s,
 149                                            ibpd->uobject->context,
 150                                            srq->rq.wq);
 151                 if (!srq->ip) {
 152                         ret = ERR_PTR(-ENOMEM);
 153                         goto bail_wq;
 154                 }
 155
 156                 err = ib_copy_to_udata(udata, &srq->ip->offset,
 157                                        sizeof(srq->ip->offset));
 158                 if (err) {
 159                         ret = ERR_PTR(err);
 160                         goto bail_ip;
 161                 }
 162         } else
 163                 srq->ip = NULL;
 164
 165         /*
 166          * ib_create_srq() will initialize srq->ibsrq.
 167          */
 168         spin_lock_init(&srq->rq.lock);
 169         srq->rq.wq->head = 0;
 170         srq->rq.wq->tail = 0;
 171         srq->limit = srq_init_attr->attr.srq_limit;
 172
 173         spin_lock(&dev->n_srqs_lock);
 174         if (dev->n_srqs_allocated == ib_ipath_max_srqs) {
 175                 spin_unlock(&dev->n_srqs_lock);
 176                 ret = ERR_PTR(-ENOMEM);
 177                 goto bail_ip;
 178         }
 179
 180         dev->n_srqs_allocated++;
 181         spin_unlock(&dev->n_srqs_lock);
 182
 183         if (srq->ip) {
 184                 spin_lock_irq(&dev->pending_lock);
 185                 list_add(&srq->ip->pending_mmaps, &dev->pending_mmaps);
 186                 spin_unlock_irq(&dev->pending_lock);
 187         }
 188
 189         ret = &srq->ibsrq;
 190         goto done;
 191
 192 bail_ip:
 193         kfree(srq->ip);
 194 bail_wq:
 195         vfree(srq->rq.wq);
 196 bail_srq:
 197         kfree(srq);
 198 done:
 199         return ret;
 200 }
 201
 202 /**
 203  * ipath_modify_srq - modify a shared receive queue
 204  * @ibsrq: the SRQ to modify
 205  * @attr: the new attributes of the SRQ
 206  * @attr_mask: indicates which attributes to modify
 207  * @udata: user data for ipathverbs.so
 208  */
 209 int ipath_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
 210                      enum ib_srq_attr_mask attr_mask,
 211                      struct ib_udata *udata)
 212 {
 213         struct ipath_srq *srq = to_isrq(ibsrq);
 214         int ret = 0;
 215
 216         if (attr_mask & IB_SRQ_MAX_WR) {
 217                 struct ipath_rwq *owq;
 218                 struct ipath_rwq *wq;
 219                 struct ipath_rwqe *p;
 220                 u32 sz, size, n, head, tail;
 221
 222                 /* Check that the requested sizes are below the limits. */
 223                 if ((attr->max_wr > ib_ipath_max_srq_wrs) ||
 224                     ((attr_mask & IB_SRQ_LIMIT) ?
 225                      attr->srq_limit : srq->limit) > attr->max_wr) {
 226                         ret = -EINVAL;
 227                         goto bail;
 228                 }
 229
 230                 sz = sizeof(struct ipath_rwqe) +
 231                         srq->rq.max_sge * sizeof(struct ib_sge);
 232                 size = attr->max_wr + 1;
 233                 wq = vmalloc_user(sizeof(struct ipath_rwq) + size * sz);
 234                 if (!wq) {
 235                         ret = -ENOMEM;
 236                         goto bail;
 237                 }
 238
 239                 /*
 240                  * Return the address of the RWQ as the offset to mmap.
 241                  * See ipath_mmap() for details.
 242                  */
 243                 if (udata && udata->inlen >= sizeof(__u64)) {
 244                         __u64 offset_addr;
 245                         __u64 offset = (__u64) wq;
 246
 247                         ret = ib_copy_from_udata(&offset_addr, udata,
 248                                                  sizeof(offset_addr));
 249                         if (ret) {
 250                                 vfree(wq);
 251                                 goto bail;
 252                         }
 253                         udata->outbuf = (void __user *) offset_addr;
 254                         ret = ib_copy_to_udata(udata, &offset,
 255                                                sizeof(offset));
 256                         if (ret) {
 257                                 vfree(wq);
 258                                 goto bail;
 259                         }
 260                 }
 261
 262                 spin_lock_irq(&srq->rq.lock);
 263                 /*
 264                  * validate head pointer value and compute
 265                  * the number of remaining WQEs.
 266                  */
 267                 owq = srq->rq.wq;
 268                 head = owq->head;
 269                 if (head >= srq->rq.size)
 270                         head = 0;
 271                 tail = owq->tail;
 272                 if (tail >= srq->rq.size)
 273                         tail = 0;
 274                 n = head;
 275                 if (n < tail)
 276                         n += srq->rq.size - tail;
 277                 else
 278                         n -= tail;
 279                 if (size <= n) {
 280                         spin_unlock_irq(&srq->rq.lock);
 281                         vfree(wq);
 282                         ret = -EINVAL;
 283                         goto bail;
 284                 }
 285                 n = 0;
 286                 p = wq->wq;
 287                 while (tail != head) {
 288                         struct ipath_rwqe *wqe;
 289                         int i;
 290
 291                         wqe = get_rwqe_ptr(&srq->rq, tail);
 292                         p->wr_id = wqe->wr_id;
 293                         p->num_sge = wqe->num_sge;
 294                         for (i = 0; i < wqe->num_sge; i++)
 295                                 p->sg_list[i] = wqe->sg_list[i];
 296                         n++;
 297                         p = (struct ipath_rwqe *)((char *) p + sz);
 298                         if (++tail >= srq->rq.size)
 299                                 tail = 0;
 300                 }
 301                 srq->rq.wq = wq;
 302                 srq->rq.size = size;
 303                 wq->head = n;
 304                 wq->tail = 0;
 305                 if (attr_mask & IB_SRQ_LIMIT)
 306                         srq->limit = attr->srq_limit;
 307                 spin_unlock_irq(&srq->rq.lock);
 308
 309                 vfree(owq);
 310
 311                 if (srq->ip) {
 312                         struct ipath_mmap_info *ip = srq->ip;
 313                         struct ipath_ibdev *dev = to_idev(srq->ibsrq.device);
 314                         u32 s = sizeof(struct ipath_rwq) + size * sz;
 315
 316                         ipath_update_mmap_info(dev, ip, s, wq);
 317                         spin_lock_irq(&dev->pending_lock);
 318                         if (list_empty(&ip->pending_mmaps))
 319                                 list_add(&ip->pending_mmaps,
 320                                          &dev->pending_mmaps);
 321                         spin_unlock_irq(&dev->pending_lock);
 322                 }
 323         } else if (attr_mask & IB_SRQ_LIMIT) {
 324                 spin_lock_irq(&srq->rq.lock);
 325                 if (attr->srq_limit >= srq->rq.size)
 326                         ret = -EINVAL;
 327                 else
 328                         srq->limit = attr->srq_limit;
 329                 spin_unlock_irq(&srq->rq.lock);
 330         }
 331
 332 bail:
 333         return ret;
 334 }
 335
 336 int ipath_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr)
 337 {
 338         struct ipath_srq *srq = to_isrq(ibsrq);
 339
 340         attr->max_wr = srq->rq.size - 1;
 341         attr->max_sge = srq->rq.max_sge;
 342         attr->srq_limit = srq->limit;
 343         return 0;
 344 }
 345
 346 /**
 347  * ipath_destroy_srq - destroy a shared receive queue
 348  * @ibsrq: the SRQ to destroy
 349  */
 350 int ipath_destroy_srq(struct ib_srq *ibsrq)
 351 {
 352         struct ipath_srq *srq = to_isrq(ibsrq);
 353         struct ipath_ibdev *dev = to_idev(ibsrq->device);
 354
 355         spin_lock(&dev->n_srqs_lock);
 356         dev->n_srqs_allocated--;
 357         spin_unlock(&dev->n_srqs_lock);
 358         if (srq->ip)
 359                 kref_put(&srq->ip->ref, ipath_release_mmap_info);
 360         else
 361                 vfree(srq->rq.wq);
 362         kfree(srq);
 363
 364         return 0;
 365 }