LXR linux/drivers/infiniband/core/umem

   1/*
   2 * Copyright (c) 2014 Mellanox Technologies. 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 <linux/kernel.h>
  34#include <linux/module.h>
  35#include <linux/interval_tree_generic.h>
  36#include <linux/sched.h>
  37#include <linux/gfp.h>
  38#include <rdma/ib_umem_odp.h>
  39
  40/*
  41 * The ib_umem list keeps track of memory regions for which the HW
  42 * device request to receive notification when the related memory
  43 * mapping is changed.
  44 *
  45 * ib_umem_lock protects the list.
  46 */
  47
  48static inline u64 node_start(struct umem_odp_node *n)
  49{
  50        struct ib_umem_odp *umem_odp =
  51                        container_of(n, struct ib_umem_odp, interval_tree);
  52
  53        return ib_umem_start(umem_odp->umem);
  54}
  55
  56/* Note that the representation of the intervals in the interval tree
  57 * considers the ending point as contained in the interval, while the
  58 * function ib_umem_end returns the first address which is not contained
  59 * in the umem.
  60 */
  61static inline u64 node_last(struct umem_odp_node *n)
  62{
  63        struct ib_umem_odp *umem_odp =
  64                        container_of(n, struct ib_umem_odp, interval_tree);
  65
  66        return ib_umem_end(umem_odp->umem) - 1;
  67}
  68
  69INTERVAL_TREE_DEFINE(struct umem_odp_node, rb, u64, __subtree_last,
  70                     node_start, node_last, , rbt_ib_umem)
  71
  72/* @last is not a part of the interval. See comment for function
  73 * node_last.
  74 */
  75int rbt_ib_umem_for_each_in_range(struct rb_root *root,
  76                                  u64 start, u64 last,
  77                                  umem_call_back cb,
  78                                  void *cookie)
  79{
  80        int ret_val = 0;
  81        struct umem_odp_node *node;
  82        struct ib_umem_odp *umem;
  83
  84        if (unlikely(start == last))
  85                return ret_val;
  86
  87        for (node = rbt_ib_umem_iter_first(root, start, last - 1); node;
  88                        node = rbt_ib_umem_iter_next(node, start, last - 1)) {
  89                umem = container_of(node, struct ib_umem_odp, interval_tree);
  90                ret_val = cb(umem->umem, start, last, cookie) || ret_val;
  91        }
  92
  93        return ret_val;
  94}
  95