drivers/infiniband/hw/ipath/ipath_keys.c

   1 /*
   2  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #include <asm/io.h>
  34
  35 #include "ipath_verbs.h"
  36
  37 /**
  38  * ipath_alloc_lkey - allocate an lkey
  39  * @rkt: lkey table in which to allocate the lkey
  40  * @mr: memory region that this lkey protects
  41  *
  42  * Returns 1 if successful, otherwise returns 0.
  43  */
  44
  45 int ipath_alloc_lkey(struct ipath_lkey_table *rkt, struct ipath_mregion *mr)
  46 {
  47         unsigned long flags;
  48         u32 r;
  49         u32 n;
  50         int ret;
  51
  52         spin_lock_irqsave(&rkt->lock, flags);
  53
  54         /* Find the next available LKEY */
  55         r = n = rkt->next;
  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                         _VERBS_INFO("LKEY table full\n");
  63                         ret = 0;
  64                         goto bail;
  65                 }
  66         }
  67         rkt->next = (r + 1) & (rkt->max - 1);
  68         /*
  69          * Make sure lkey is never zero which is reserved to indicate an
  70          * unrestricted LKEY.
  71          */
  72         rkt->gen++;
  73         mr->lkey = (r << (32 - ib_ipath_lkey_table_size)) |
  74                 ((((1 << (24 - ib_ipath_lkey_table_size)) - 1) & rkt->gen)
  75                  << 8);
  76         if (mr->lkey == 0) {
  77                 mr->lkey |= 1 << 8;
  78                 rkt->gen++;
  79         }
  80         rkt->table[r] = mr;
  81         spin_unlock_irqrestore(&rkt->lock, flags);
  82
  83         ret = 1;
  84
  85 bail:
  86         return ret;
  87 }
  88
  89 /**
  90  * ipath_free_lkey - free an lkey
  91  * @rkt: table from which to free the lkey
  92  * @lkey: lkey id to free
  93  */
  94 void ipath_free_lkey(struct ipath_lkey_table *rkt, u32 lkey)
  95 {
  96         unsigned long flags;
  97         u32 r;
  98
  99         if (lkey == 0)
 100                 return;
 101         r = lkey >> (32 - ib_ipath_lkey_table_size);
 102         spin_lock_irqsave(&rkt->lock, flags);
 103         rkt->table[r] = NULL;
 104         spin_unlock_irqrestore(&rkt->lock, flags);
 105 }
 106
 107 /**
 108  * ipath_lkey_ok - check IB SGE for validity and initialize
 109  * @rkt: table containing lkey to check SGE against
 110  * @isge: outgoing internal SGE
 111  * @sge: SGE to check
 112  * @acc: access flags
 113  *
 114  * Return 1 if valid and successful, otherwise returns 0.
 115  *
 116  * Check the IB SGE for validity and initialize our internal version
 117  * of it.
 118  */
 119 int ipath_lkey_ok(struct ipath_lkey_table *rkt, struct ipath_sge *isge,
 120                   struct ib_sge *sge, int acc)
 121 {
 122         struct ipath_mregion *mr;
 123         size_t off;
 124         int ret;
 125
 126         /*
 127          * We use LKEY == zero to mean a physical kmalloc() address.
 128          * This is a bit of a hack since we rely on dma_map_single()
 129          * being reversible by calling bus_to_virt().
 130          */
 131         if (sge->lkey == 0) {
 132                 isge->mr = NULL;
 133                 isge->vaddr = bus_to_virt(sge->addr);
 134                 isge->length = sge->length;
 135                 isge->sge_length = sge->length;
 136                 ret = 1;
 137                 goto bail;
 138         }
 139         spin_lock(&rkt->lock);
 140         mr = rkt->table[(sge->lkey >> (32 - ib_ipath_lkey_table_size))];
 141         spin_unlock(&rkt->lock);
 142         if (unlikely(mr == NULL || mr->lkey != sge->lkey)) {
 143                 ret = 0;
 144                 goto bail;
 145         }
 146
 147         off = sge->addr - mr->user_base;
 148         if (unlikely(sge->addr < mr->user_base ||
 149                      off + sge->length > mr->length ||
 150                      (mr->access_flags & acc) != acc)) {
 151                 ret = 0;
 152                 goto bail;
 153         }
 154
 155         off += mr->offset;
 156         isge->mr = mr;
 157         isge->m = 0;
 158         isge->n = 0;
 159         while (off >= mr->map[isge->m]->segs[isge->n].length) {
 160                 off -= mr->map[isge->m]->segs[isge->n].length;
 161                 isge->n++;
 162                 if (isge->n >= IPATH_SEGSZ) {
 163                         isge->m++;
 164                         isge->n = 0;
 165                 }
 166         }
 167         isge->vaddr = mr->map[isge->m]->segs[isge->n].vaddr + off;
 168         isge->length = mr->map[isge->m]->segs[isge->n].length - off;
 169         isge->sge_length = sge->length;
 170
 171         ret = 1;
 172
 173 bail:
 174         return ret;
 175 }
 176
 177 /**
 178  * ipath_rkey_ok - check the IB virtual address, length, and RKEY
 179  * @dev: infiniband device
 180  * @ss: SGE state
 181  * @len: length of data
 182  * @vaddr: virtual address to place data
 183  * @rkey: rkey to check
 184  * @acc: access flags
 185  *
 186  * Return 1 if successful, otherwise 0.
 187  *
 188  * The QP r_rq.lock should be held.
 189  */
 190 int ipath_rkey_ok(struct ipath_ibdev *dev, struct ipath_sge_state *ss,
 191                   u32 len, u64 vaddr, u32 rkey, int acc)
 192 {
 193         struct ipath_lkey_table *rkt = &dev->lk_table;
 194         struct ipath_sge *sge = &ss->sge;
 195         struct ipath_mregion *mr;
 196         size_t off;
 197         int ret;
 198
 199         spin_lock(&rkt->lock);
 200         mr = rkt->table[(rkey >> (32 - ib_ipath_lkey_table_size))];
 201         spin_unlock(&rkt->lock);
 202         if (unlikely(mr == NULL || mr->lkey != rkey)) {
 203                 ret = 0;
 204                 goto bail;
 205         }
 206
 207         off = vaddr - mr->iova;
 208         if (unlikely(vaddr < mr->iova || off + len > mr->length ||
 209                      (mr->access_flags & acc) == 0)) {
 210                 ret = 0;
 211                 goto bail;
 212         }
 213
 214         off += mr->offset;
 215         sge->mr = mr;
 216         sge->m = 0;
 217         sge->n = 0;
 218         while (off >= mr->map[sge->m]->segs[sge->n].length) {
 219                 off -= mr->map[sge->m]->segs[sge->n].length;
 220                 sge->n++;
 221                 if (sge->n >= IPATH_SEGSZ) {
 222                         sge->m++;
 223                         sge->n = 0;
 224                 }
 225         }
 226         sge->vaddr = mr->map[sge->m]->segs[sge->n].vaddr + off;
 227         sge->length = mr->map[sge->m]->segs[sge->n].length - off;
 228         sge->sge_length = len;
 229         ss->sg_list = NULL;
 230         ss->num_sge = 1;
 231
 232         ret = 1;
 233
 234 bail:
 235         return ret;
 236 }