linux/drivers/infiniband/core/umem_rbtree.c
Artemy Kovalyov d07d1d70ce IB/umem: Update on demand page (ODP) support
Currently ODP MR may explicitly register virtual address space area
of limited length.
This change allows MR to cover entire process virtual address space
dynamicaly adding/removing translation entries to device MTT.

Add following changes to support implicit MR:
* Allow umem to be zero size to back-up implicit MR.
* Add new function ib_alloc_odp_umem() to add virtual memory regions
  to implicit MR dynamically on demand.
* Add new function rbt_ib_umem_lookup() to find dynamically added
  virtual memory regions.
* Expose function rbt_ib_umem_for_each_in_range() to other modules and
  make it safe

Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-02-14 11:41:17 -05:00

110 lines
3.4 KiB
C

/*
* Copyright (c) 2014 Mellanox Technologies. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interval_tree_generic.h>
#include <linux/sched.h>
#include <linux/gfp.h>
#include <rdma/ib_umem_odp.h>
/*
* The ib_umem list keeps track of memory regions for which the HW
* device request to receive notification when the related memory
* mapping is changed.
*
* ib_umem_lock protects the list.
*/
static inline u64 node_start(struct umem_odp_node *n)
{
struct ib_umem_odp *umem_odp =
container_of(n, struct ib_umem_odp, interval_tree);
return ib_umem_start(umem_odp->umem);
}
/* Note that the representation of the intervals in the interval tree
* considers the ending point as contained in the interval, while the
* function ib_umem_end returns the first address which is not contained
* in the umem.
*/
static inline u64 node_last(struct umem_odp_node *n)
{
struct ib_umem_odp *umem_odp =
container_of(n, struct ib_umem_odp, interval_tree);
return ib_umem_end(umem_odp->umem) - 1;
}
INTERVAL_TREE_DEFINE(struct umem_odp_node, rb, u64, __subtree_last,
node_start, node_last, , rbt_ib_umem)
/* @last is not a part of the interval. See comment for function
* node_last.
*/
int rbt_ib_umem_for_each_in_range(struct rb_root *root,
u64 start, u64 last,
umem_call_back cb,
void *cookie)
{
int ret_val = 0;
struct umem_odp_node *node, *next;
struct ib_umem_odp *umem;
if (unlikely(start == last))
return ret_val;
for (node = rbt_ib_umem_iter_first(root, start, last - 1);
node; node = next) {
next = rbt_ib_umem_iter_next(node, start, last - 1);
umem = container_of(node, struct ib_umem_odp, interval_tree);
ret_val = cb(umem->umem, start, last, cookie) || ret_val;
}
return ret_val;
}
EXPORT_SYMBOL(rbt_ib_umem_for_each_in_range);
struct ib_umem_odp *rbt_ib_umem_lookup(struct rb_root *root,
u64 addr, u64 length)
{
struct umem_odp_node *node;
node = rbt_ib_umem_iter_first(root, addr, addr + length - 1);
if (node)
return container_of(node, struct ib_umem_odp, interval_tree);
return NULL;
}
EXPORT_SYMBOL(rbt_ib_umem_lookup);