1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright (c) 2007 Cisco Systems, Inc. All rights reserved.
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * This software is available to you under a choice of one of two
5*4882a593Smuzhiyun * licenses. You may choose to be licensed under the terms of the GNU
6*4882a593Smuzhiyun * General Public License (GPL) Version 2, available from the file
7*4882a593Smuzhiyun * COPYING in the main directory of this source tree, or the
8*4882a593Smuzhiyun * OpenIB.org BSD license below:
9*4882a593Smuzhiyun *
10*4882a593Smuzhiyun * Redistribution and use in source and binary forms, with or
11*4882a593Smuzhiyun * without modification, are permitted provided that the following
12*4882a593Smuzhiyun * conditions are met:
13*4882a593Smuzhiyun *
14*4882a593Smuzhiyun * - Redistributions of source code must retain the above
15*4882a593Smuzhiyun * copyright notice, this list of conditions and the following
16*4882a593Smuzhiyun * disclaimer.
17*4882a593Smuzhiyun *
18*4882a593Smuzhiyun * - Redistributions in binary form must reproduce the above
19*4882a593Smuzhiyun * copyright notice, this list of conditions and the following
20*4882a593Smuzhiyun * disclaimer in the documentation and/or other materials
21*4882a593Smuzhiyun * provided with the distribution.
22*4882a593Smuzhiyun *
23*4882a593Smuzhiyun * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24*4882a593Smuzhiyun * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25*4882a593Smuzhiyun * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26*4882a593Smuzhiyun * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27*4882a593Smuzhiyun * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28*4882a593Smuzhiyun * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29*4882a593Smuzhiyun * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30*4882a593Smuzhiyun * SOFTWARE.
31*4882a593Smuzhiyun */
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun #include <linux/slab.h>
34*4882a593Smuzhiyun #include <rdma/uverbs_ioctl.h>
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun #include "mlx4_ib.h"
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun struct mlx4_ib_user_db_page {
39*4882a593Smuzhiyun struct list_head list;
40*4882a593Smuzhiyun struct ib_umem *umem;
41*4882a593Smuzhiyun unsigned long user_virt;
42*4882a593Smuzhiyun int refcnt;
43*4882a593Smuzhiyun };
44*4882a593Smuzhiyun
mlx4_ib_db_map_user(struct ib_udata * udata,unsigned long virt,struct mlx4_db * db)45*4882a593Smuzhiyun int mlx4_ib_db_map_user(struct ib_udata *udata, unsigned long virt,
46*4882a593Smuzhiyun struct mlx4_db *db)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun struct mlx4_ib_user_db_page *page;
49*4882a593Smuzhiyun int err = 0;
50*4882a593Smuzhiyun struct mlx4_ib_ucontext *context = rdma_udata_to_drv_context(
51*4882a593Smuzhiyun udata, struct mlx4_ib_ucontext, ibucontext);
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun mutex_lock(&context->db_page_mutex);
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun list_for_each_entry(page, &context->db_page_list, list)
56*4882a593Smuzhiyun if (page->user_virt == (virt & PAGE_MASK))
57*4882a593Smuzhiyun goto found;
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun page = kmalloc(sizeof *page, GFP_KERNEL);
60*4882a593Smuzhiyun if (!page) {
61*4882a593Smuzhiyun err = -ENOMEM;
62*4882a593Smuzhiyun goto out;
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun page->user_virt = (virt & PAGE_MASK);
66*4882a593Smuzhiyun page->refcnt = 0;
67*4882a593Smuzhiyun page->umem = ib_umem_get(context->ibucontext.device, virt & PAGE_MASK,
68*4882a593Smuzhiyun PAGE_SIZE, 0);
69*4882a593Smuzhiyun if (IS_ERR(page->umem)) {
70*4882a593Smuzhiyun err = PTR_ERR(page->umem);
71*4882a593Smuzhiyun kfree(page);
72*4882a593Smuzhiyun goto out;
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun list_add(&page->list, &context->db_page_list);
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun found:
78*4882a593Smuzhiyun db->dma = sg_dma_address(page->umem->sg_head.sgl) + (virt & ~PAGE_MASK);
79*4882a593Smuzhiyun db->u.user_page = page;
80*4882a593Smuzhiyun ++page->refcnt;
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun out:
83*4882a593Smuzhiyun mutex_unlock(&context->db_page_mutex);
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun return err;
86*4882a593Smuzhiyun }
87*4882a593Smuzhiyun
mlx4_ib_db_unmap_user(struct mlx4_ib_ucontext * context,struct mlx4_db * db)88*4882a593Smuzhiyun void mlx4_ib_db_unmap_user(struct mlx4_ib_ucontext *context, struct mlx4_db *db)
89*4882a593Smuzhiyun {
90*4882a593Smuzhiyun mutex_lock(&context->db_page_mutex);
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun if (!--db->u.user_page->refcnt) {
93*4882a593Smuzhiyun list_del(&db->u.user_page->list);
94*4882a593Smuzhiyun ib_umem_release(db->u.user_page->umem);
95*4882a593Smuzhiyun kfree(db->u.user_page);
96*4882a593Smuzhiyun }
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun mutex_unlock(&context->db_page_mutex);
99*4882a593Smuzhiyun }
100