drivers/infiniband/core/mr_pool.c

   1 /*
   2  * Copyright (c) 2016 HGST, a Western Digital Company.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  */
  13 #include <rdma/ib_verbs.h>
  14 #include <rdma/mr_pool.h>
  15
  16 struct ib_mr *ib_mr_pool_get(struct ib_qp *qp, struct list_head *list)
  17 {
  18         struct ib_mr *mr;
  19         unsigned long flags;
  20
  21         spin_lock_irqsave(&qp->mr_lock, flags);
  22         mr = list_first_entry_or_null(list, struct ib_mr, qp_entry);
  23         if (mr) {
  24                 list_del(&mr->qp_entry);
  25                 qp->mrs_used++;
  26         }
  27         spin_unlock_irqrestore(&qp->mr_lock, flags);
  28
  29         return mr;
  30 }
  31 EXPORT_SYMBOL(ib_mr_pool_get);
  32
  33 void ib_mr_pool_put(struct ib_qp *qp, struct list_head *list, struct ib_mr *mr)
  34 {
  35         unsigned long flags;
  36
  37         spin_lock_irqsave(&qp->mr_lock, flags);
  38         list_add(&mr->qp_entry, list);
  39         qp->mrs_used--;
  40         spin_unlock_irqrestore(&qp->mr_lock, flags);
  41 }
  42 EXPORT_SYMBOL(ib_mr_pool_put);
  43
  44 int ib_mr_pool_init(struct ib_qp *qp, struct list_head *list, int nr,
  45                 enum ib_mr_type type, u32 max_num_sg)
  46 {
  47         struct ib_mr *mr;
  48         unsigned long flags;
  49         int ret, i;
  50
  51         for (i = 0; i < nr; i++) {
  52                 mr = ib_alloc_mr(qp->pd, type, max_num_sg);
  53                 if (IS_ERR(mr)) {
  54                         ret = PTR_ERR(mr);
  55                         goto out;
  56                 }
  57
  58                 spin_lock_irqsave(&qp->mr_lock, flags);
  59                 list_add_tail(&mr->qp_entry, list);
  60                 spin_unlock_irqrestore(&qp->mr_lock, flags);
  61         }
  62
  63         return 0;
  64 out:
  65         ib_mr_pool_destroy(qp, list);
  66         return ret;
  67 }
  68 EXPORT_SYMBOL(ib_mr_pool_init);
  69
  70 void ib_mr_pool_destroy(struct ib_qp *qp, struct list_head *list)
  71 {
  72         struct ib_mr *mr;
  73         unsigned long flags;
  74
  75         spin_lock_irqsave(&qp->mr_lock, flags);
  76         while (!list_empty(list)) {
  77                 mr = list_first_entry(list, struct ib_mr, qp_entry);
  78                 list_del(&mr->qp_entry);
  79
  80                 spin_unlock_irqrestore(&qp->mr_lock, flags);
  81                 ib_dereg_mr(mr);
  82                 spin_lock_irqsave(&qp->mr_lock, flags);
  83         }
  84         spin_unlock_irqrestore(&qp->mr_lock, flags);
  85 }
  86 EXPORT_SYMBOL(ib_mr_pool_destroy);