release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/infiniband/hw/qib/qib_keys.c

   1 /*
   2  * Copyright (c) 2006, 2007, 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 "qib.h"
  35
  36 /**
  37  * qib_alloc_lkey - allocate an lkey
  38  * @rkt: lkey table in which to allocate the lkey
  39  * @mr: memory region that this lkey protects
  40  *
  41  * Returns 1 if successful, otherwise returns 0.
  42  */
  43
  44 int qib_alloc_lkey(struct qib_lkey_table *rkt, struct qib_mregion *mr)
  45 {
  46         unsigned long flags;
  47         u32 r;
  48         u32 n;
  49         int ret;
  50
  51         spin_lock_irqsave(&rkt->lock, flags);
  52
  53         /* Find the next available LKEY */
  54         r = rkt->next;
  55         n = r;
  56         for (;;) {
  57                 if (rkt->table[r] == NULL)
  58                         break;
  59                 r = (r + 1) & (rkt->max - 1);
  60                 if (r == n) {
  61                         spin_unlock_irqrestore(&rkt->lock, flags);
  62                         ret = 0;
  63                         goto bail;
  64                 }
  65         }
  66         rkt->next = (r + 1) & (rkt->max - 1);
  67         /*
  68          * Make sure lkey is never zero which is reserved to indicate an
  69          * unrestricted LKEY.
  70          */
  71         rkt->gen++;
  72         mr->lkey = (r << (32 - ib_qib_lkey_table_size)) |
  73                 ((((1 << (24 - ib_qib_lkey_table_size)) - 1) & rkt->gen)
  74                  << 8);
  75         if (mr->lkey == 0) {
  76                 mr->lkey |= 1 << 8;
  77                 rkt->gen++;
  78         }
  79         rkt->table[r] = mr;
  80         spin_unlock_irqrestore(&rkt->lock, flags);
  81
  82         ret = 1;
  83
  84 bail:
  85         return ret;
  86 }
  87
  88 /**
  89  * qib_free_lkey - free an lkey
  90  * @rkt: table from which to free the lkey
  91  * @lkey: lkey id to free
  92  */
  93 int qib_free_lkey(struct qib_ibdev *dev, struct qib_mregion *mr)
  94 {
  95         unsigned long flags;
  96         u32 lkey = mr->lkey;
  97         u32 r;
  98         int ret;
  99
 100         spin_lock_irqsave(&dev->lk_table.lock, flags);
 101         if (lkey == 0) {
 102                 if (dev->dma_mr && dev->dma_mr == mr) {
 103                         ret = atomic_read(&dev->dma_mr->refcount);
 104                         if (!ret)
 105                                 dev->dma_mr = NULL;
 106                 } else
 107                         ret = 0;
 108         } else {
 109                 r = lkey >> (32 - ib_qib_lkey_table_size);
 110                 ret = atomic_read(&dev->lk_table.table[r]->refcount);
 111                 if (!ret)
 112                         dev->lk_table.table[r] = NULL;
 113         }
 114         spin_unlock_irqrestore(&dev->lk_table.lock, flags);
 115
 116         if (ret)
 117                 ret = -EBUSY;
 118         return ret;
 119 }
 120
 121 /**
 122  * qib_lkey_ok - check IB SGE for validity and initialize
 123  * @rkt: table containing lkey to check SGE against
 124  * @isge: outgoing internal SGE
 125  * @sge: SGE to check
 126  * @acc: access flags
 127  *
 128  * Return 1 if valid and successful, otherwise returns 0.
 129  *
 130  * Check the IB SGE for validity and initialize our internal version
 131  * of it.
 132  */
 133 int qib_lkey_ok(struct qib_lkey_table *rkt, struct qib_pd *pd,
 134                 struct qib_sge *isge, struct ib_sge *sge, int acc)
 135 {
 136         struct qib_mregion *mr;
 137         unsigned n, m;
 138         size_t off;
 139         int ret = 0;
 140         unsigned long flags;
 141
 142         /*
 143          * We use LKEY == zero for kernel virtual addresses
 144          * (see qib_get_dma_mr and qib_dma.c).
 145          */
 146         spin_lock_irqsave(&rkt->lock, flags);
 147         if (sge->lkey == 0) {
 148                 struct qib_ibdev *dev = to_idev(pd->ibpd.device);
 149
 150                 if (pd->user)
 151                         goto bail;
 152                 if (!dev->dma_mr)
 153                         goto bail;
 154                 atomic_inc(&dev->dma_mr->refcount);
 155                 isge->mr = dev->dma_mr;
 156                 isge->vaddr = (void *) sge->addr;
 157                 isge->length = sge->length;
 158                 isge->sge_length = sge->length;
 159                 isge->m = 0;
 160                 isge->n = 0;
 161                 goto ok;
 162         }
 163         mr = rkt->table[(sge->lkey >> (32 - ib_qib_lkey_table_size))];
 164         if (unlikely(mr == NULL || mr->lkey != sge->lkey ||
 165                      mr->pd != &pd->ibpd))
 166                 goto bail;
 167
 168         off = sge->addr - mr->user_base;
 169         if (unlikely(sge->addr < mr->user_base ||
 170                      off + sge->length > mr->length ||
 171                      (mr->access_flags & acc) != acc))
 172                 goto bail;
 173
 174         off += mr->offset;
 175         m = 0;
 176         n = 0;
 177         while (off >= mr->map[m]->segs[n].length) {
 178                 off -= mr->map[m]->segs[n].length;
 179                 n++;
 180                 if (n >= QIB_SEGSZ) {
 181                         m++;
 182                         n = 0;
 183                 }
 184         }
 185         atomic_inc(&mr->refcount);
 186         isge->mr = mr;
 187         isge->vaddr = mr->map[m]->segs[n].vaddr + off;
 188         isge->length = mr->map[m]->segs[n].length - off;
 189         isge->sge_length = sge->length;
 190         isge->m = m;
 191         isge->n = n;
 192 ok:
 193         ret = 1;
 194 bail:
 195         spin_unlock_irqrestore(&rkt->lock, flags);
 196         return ret;
 197 }
 198
 199 /**
 200  * qib_rkey_ok - check the IB virtual address, length, and RKEY
 201  * @dev: infiniband device
 202  * @ss: SGE state
 203  * @len: length of data
 204  * @vaddr: virtual address to place data
 205  * @rkey: rkey to check
 206  * @acc: access flags
 207  *
 208  * Return 1 if successful, otherwise 0.
 209  */
 210 int qib_rkey_ok(struct qib_qp *qp, struct qib_sge *sge,
 211                 u32 len, u64 vaddr, u32 rkey, int acc)
 212 {
 213         struct qib_lkey_table *rkt = &to_idev(qp->ibqp.device)->lk_table;
 214         struct qib_mregion *mr;
 215         unsigned n, m;
 216         size_t off;
 217         int ret = 0;
 218         unsigned long flags;
 219
 220         /*
 221          * We use RKEY == zero for kernel virtual addresses
 222          * (see qib_get_dma_mr and qib_dma.c).
 223          */
 224         spin_lock_irqsave(&rkt->lock, flags);
 225         if (rkey == 0) {
 226                 struct qib_pd *pd = to_ipd(qp->ibqp.pd);
 227                 struct qib_ibdev *dev = to_idev(pd->ibpd.device);
 228
 229                 if (pd->user)
 230                         goto bail;
 231                 if (!dev->dma_mr)
 232                         goto bail;
 233                 atomic_inc(&dev->dma_mr->refcount);
 234                 sge->mr = dev->dma_mr;
 235                 sge->vaddr = (void *) vaddr;
 236                 sge->length = len;
 237                 sge->sge_length = len;
 238                 sge->m = 0;
 239                 sge->n = 0;
 240                 goto ok;
 241         }
 242
 243         mr = rkt->table[(rkey >> (32 - ib_qib_lkey_table_size))];
 244         if (unlikely(mr == NULL || mr->lkey != rkey || qp->ibqp.pd != mr->pd))
 245                 goto bail;
 246
 247         off = vaddr - mr->iova;
 248         if (unlikely(vaddr < mr->iova || off + len > mr->length ||
 249                      (mr->access_flags & acc) == 0))
 250                 goto bail;
 251
 252         off += mr->offset;
 253         m = 0;
 254         n = 0;
 255         while (off >= mr->map[m]->segs[n].length) {
 256                 off -= mr->map[m]->segs[n].length;
 257                 n++;
 258                 if (n >= QIB_SEGSZ) {
 259                         m++;
 260                         n = 0;
 261                 }
 262         }
 263         atomic_inc(&mr->refcount);
 264         sge->mr = mr;
 265         sge->vaddr = mr->map[m]->segs[n].vaddr + off;
 266         sge->length = mr->map[m]->segs[n].length - off;
 267         sge->sge_length = len;
 268         sge->m = m;
 269         sge->n = n;
 270 ok:
 271         ret = 1;
 272 bail:
 273         spin_unlock_irqrestore(&rkt->lock, flags);
 274         return ret;
 275 }
 276
 277 /*
 278  * Initialize the memory region specified by the work reqeust.
 279  */
 280 int qib_fast_reg_mr(struct qib_qp *qp, struct ib_send_wr *wr)
 281 {
 282         struct qib_lkey_table *rkt = &to_idev(qp->ibqp.device)->lk_table;
 283         struct qib_pd *pd = to_ipd(qp->ibqp.pd);
 284         struct qib_mregion *mr;
 285         u32 rkey = wr->wr.fast_reg.rkey;
 286         unsigned i, n, m;
 287         int ret = -EINVAL;
 288         unsigned long flags;
 289         u64 *page_list;
 290         size_t ps;
 291
 292         spin_lock_irqsave(&rkt->lock, flags);
 293         if (pd->user || rkey == 0)
 294                 goto bail;
 295
 296         mr = rkt->table[(rkey >> (32 - ib_qib_lkey_table_size))];
 297         if (unlikely(mr == NULL || qp->ibqp.pd != mr->pd))
 298                 goto bail;
 299
 300         if (wr->wr.fast_reg.page_list_len > mr->max_segs)
 301                 goto bail;
 302
 303         ps = 1UL << wr->wr.fast_reg.page_shift;
 304         if (wr->wr.fast_reg.length > ps * wr->wr.fast_reg.page_list_len)
 305                 goto bail;
 306
 307         mr->user_base = wr->wr.fast_reg.iova_start;
 308         mr->iova = wr->wr.fast_reg.iova_start;
 309         mr->lkey = rkey;
 310         mr->length = wr->wr.fast_reg.length;
 311         mr->access_flags = wr->wr.fast_reg.access_flags;
 312         page_list = wr->wr.fast_reg.page_list->page_list;
 313         m = 0;
 314         n = 0;
 315         for (i = 0; i < wr->wr.fast_reg.page_list_len; i++) {
 316                 mr->map[m]->segs[n].vaddr = (void *) page_list[i];
 317                 mr->map[m]->segs[n].length = ps;
 318                 if (++n == QIB_SEGSZ) {
 319                         m++;
 320                         n = 0;
 321                 }
 322         }
 323
 324         ret = 0;
 325 bail:
 326         spin_unlock_irqrestore(&rkt->lock, flags);
 327         return ret;
 328 }