1 /* 2 * Copyright (c) 2005 Topspin Communications. 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 #define _GNU_SOURCE 33 #include <config.h> 34 35 #include <stdlib.h> 36 #include <pthread.h> 37 #include <string.h> 38 39 #include "mlx4.h" 40 41 struct mlx4_db_page { 42 struct mlx4_db_page *prev, *next; 43 struct mlx4_buf buf; 44 int num_db; 45 int use_cnt; 46 unsigned long free[0]; 47 }; 48 49 static const int db_size[] = { 50 [MLX4_DB_TYPE_CQ] = 8, 51 [MLX4_DB_TYPE_RQ] = 4, 52 }; 53 54 static struct mlx4_db_page *__add_page(struct mlx4_context *context, 55 enum mlx4_db_type type) 56 { 57 struct mlx4_db_page *page; 58 int ps = to_mdev(context->ibv_ctx.device)->page_size; 59 int pp; 60 int i; 61 62 pp = ps / db_size[type]; 63 64 page = malloc(sizeof *page + pp / 8); 65 if (!page) 66 return NULL; 67 68 if (mlx4_alloc_buf(&page->buf, ps, ps)) { 69 free(page); 70 return NULL; 71 } 72 73 page->num_db = pp; 74 page->use_cnt = 0; 75 for (i = 0; i < pp / (sizeof (long) * 8); ++i) 76 page->free[i] = ~0; 77 78 page->prev = NULL; 79 page->next = context->db_list[type]; 80 context->db_list[type] = page; 81 if (page->next) 82 page->next->prev = page; 83 84 return page; 85 } 86 87 uint32_t *mlx4_alloc_db(struct mlx4_context *context, enum mlx4_db_type type) 88 { 89 struct mlx4_db_page *page; 90 uint32_t *db = NULL; 91 int i, j; 92 93 pthread_mutex_lock(&context->db_list_mutex); 94 95 for (page = context->db_list[type]; page; page = page->next) 96 if (page->use_cnt < page->num_db) 97 goto found; 98 99 page = __add_page(context, type); 100 if (!page) 101 goto out; 102 103 found: 104 ++page->use_cnt; 105 106 for (i = 0; !page->free[i]; ++i) 107 /* nothing */; 108 109 j = ffsl(page->free[i]); 110 page->free[i] &= ~(1UL << (j - 1)); 111 db = page->buf.buf + (i * 8 * sizeof (long) + (j - 1)) * db_size[type]; 112 113 out: 114 pthread_mutex_unlock(&context->db_list_mutex); 115 116 return db; 117 } 118 119 void mlx4_free_db(struct mlx4_context *context, enum mlx4_db_type type, uint32_t *db) 120 { 121 struct mlx4_db_page *page; 122 uintptr_t ps = to_mdev(context->ibv_ctx.device)->page_size; 123 int i; 124 125 pthread_mutex_lock(&context->db_list_mutex); 126 127 for (page = context->db_list[type]; page; page = page->next) 128 if (((uintptr_t) db & ~(ps - 1)) == (uintptr_t) page->buf.buf) 129 break; 130 131 if (!page) 132 goto out; 133 134 i = ((void *) db - page->buf.buf) / db_size[type]; 135 page->free[i / (8 * sizeof (long))] |= 1UL << (i % (8 * sizeof (long))); 136 137 if (!--page->use_cnt) { 138 if (page->prev) 139 page->prev->next = page->next; 140 else 141 context->db_list[type] = page->next; 142 if (page->next) 143 page->next->prev = page->prev; 144 145 mlx4_free_buf(&page->buf); 146 free(page); 147 } 148 149 out: 150 pthread_mutex_unlock(&context->db_list_mutex); 151 } 152