1 /*- 2 * Copyright (c) 2013-2015, Mellanox Technologies, Ltd. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS `AS IS' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * $FreeBSD$ 26 */ 27 28 #include "opt_rss.h" 29 #include "opt_ratelimit.h" 30 31 #include <linux/kref.h> 32 #include <linux/slab.h> 33 #include <rdma/ib_umem.h> 34 35 #include <dev/mlx5/mlx5_ib/mlx5_ib.h> 36 37 struct mlx5_ib_user_db_page { 38 struct list_head list; 39 struct ib_umem *umem; 40 unsigned long user_virt; 41 int refcnt; 42 }; 43 44 int mlx5_ib_db_map_user(struct mlx5_ib_ucontext *context, unsigned long virt, 45 struct mlx5_db *db) 46 { 47 struct mlx5_ib_user_db_page *page; 48 int err = 0; 49 50 mutex_lock(&context->db_page_mutex); 51 52 list_for_each_entry(page, &context->db_page_list, list) 53 if (page->user_virt == (virt & PAGE_MASK)) 54 goto found; 55 56 page = kmalloc(sizeof(*page), GFP_KERNEL); 57 if (!page) { 58 err = -ENOMEM; 59 goto out; 60 } 61 62 page->user_virt = (virt & PAGE_MASK); 63 page->refcnt = 0; 64 page->umem = ib_umem_get(&context->ibucontext, virt & PAGE_MASK, 65 PAGE_SIZE, 0, 0); 66 if (IS_ERR(page->umem)) { 67 err = PTR_ERR(page->umem); 68 kfree(page); 69 goto out; 70 } 71 72 list_add(&page->list, &context->db_page_list); 73 74 found: 75 db->dma = sg_dma_address(page->umem->sg_head.sgl) + (virt & ~PAGE_MASK); 76 db->u.user_page = page; 77 ++page->refcnt; 78 79 out: 80 mutex_unlock(&context->db_page_mutex); 81 82 return err; 83 } 84 85 void mlx5_ib_db_unmap_user(struct mlx5_ib_ucontext *context, struct mlx5_db *db) 86 { 87 mutex_lock(&context->db_page_mutex); 88 89 if (!--db->u.user_page->refcnt) { 90 list_del(&db->u.user_page->list); 91 ib_umem_release(db->u.user_page->umem); 92 kfree(db->u.user_page); 93 } 94 95 mutex_unlock(&context->db_page_mutex); 96 } 97