]>
Commit | Line | Data |
---|---|---|
225c7b1f RD |
1 | /* |
2 | * Copyright (c) 2007 Cisco Systems, Inc. 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/slab.h> | |
34 | ||
35 | #include "mlx4_ib.h" | |
36 | ||
37 | struct mlx4_ib_db_pgdir { | |
38 | struct list_head list; | |
39 | DECLARE_BITMAP(order0, MLX4_IB_DB_PER_PAGE); | |
40 | DECLARE_BITMAP(order1, MLX4_IB_DB_PER_PAGE / 2); | |
41 | unsigned long *bits[2]; | |
42 | __be32 *db_page; | |
43 | dma_addr_t db_dma; | |
44 | }; | |
45 | ||
46 | static struct mlx4_ib_db_pgdir *mlx4_ib_alloc_db_pgdir(struct mlx4_ib_dev *dev) | |
47 | { | |
48 | struct mlx4_ib_db_pgdir *pgdir; | |
49 | ||
50 | pgdir = kzalloc(sizeof *pgdir, GFP_KERNEL); | |
51 | if (!pgdir) | |
52 | return NULL; | |
53 | ||
54 | bitmap_fill(pgdir->order1, MLX4_IB_DB_PER_PAGE / 2); | |
55 | pgdir->bits[0] = pgdir->order0; | |
56 | pgdir->bits[1] = pgdir->order1; | |
57 | pgdir->db_page = dma_alloc_coherent(dev->ib_dev.dma_device, | |
58 | PAGE_SIZE, &pgdir->db_dma, | |
59 | GFP_KERNEL); | |
60 | if (!pgdir->db_page) { | |
61 | kfree(pgdir); | |
62 | return NULL; | |
63 | } | |
64 | ||
65 | return pgdir; | |
66 | } | |
67 | ||
68 | static int mlx4_ib_alloc_db_from_pgdir(struct mlx4_ib_db_pgdir *pgdir, | |
69 | struct mlx4_ib_db *db, int order) | |
70 | { | |
71 | int o; | |
72 | int i; | |
73 | ||
74 | for (o = order; o <= 1; ++o) { | |
75 | i = find_first_bit(pgdir->bits[o], MLX4_IB_DB_PER_PAGE >> o); | |
76 | if (i < MLX4_IB_DB_PER_PAGE >> o) | |
77 | goto found; | |
78 | } | |
79 | ||
80 | return -ENOMEM; | |
81 | ||
82 | found: | |
83 | clear_bit(i, pgdir->bits[o]); | |
84 | ||
85 | i <<= o; | |
86 | ||
87 | if (o > order) | |
88 | set_bit(i ^ 1, pgdir->bits[order]); | |
89 | ||
90 | db->u.pgdir = pgdir; | |
91 | db->index = i; | |
92 | db->db = pgdir->db_page + db->index; | |
93 | db->dma = pgdir->db_dma + db->index * 4; | |
94 | db->order = order; | |
95 | ||
96 | return 0; | |
97 | } | |
98 | ||
99 | int mlx4_ib_db_alloc(struct mlx4_ib_dev *dev, struct mlx4_ib_db *db, int order) | |
100 | { | |
101 | struct mlx4_ib_db_pgdir *pgdir; | |
102 | int ret = 0; | |
103 | ||
104 | mutex_lock(&dev->pgdir_mutex); | |
105 | ||
106 | list_for_each_entry(pgdir, &dev->pgdir_list, list) | |
107 | if (!mlx4_ib_alloc_db_from_pgdir(pgdir, db, order)) | |
108 | goto out; | |
109 | ||
110 | pgdir = mlx4_ib_alloc_db_pgdir(dev); | |
111 | if (!pgdir) { | |
112 | ret = -ENOMEM; | |
113 | goto out; | |
114 | } | |
115 | ||
116 | list_add(&pgdir->list, &dev->pgdir_list); | |
117 | ||
118 | /* This should never fail -- we just allocated an empty page: */ | |
119 | WARN_ON(mlx4_ib_alloc_db_from_pgdir(pgdir, db, order)); | |
120 | ||
121 | out: | |
122 | mutex_unlock(&dev->pgdir_mutex); | |
123 | ||
124 | return ret; | |
125 | } | |
126 | ||
127 | void mlx4_ib_db_free(struct mlx4_ib_dev *dev, struct mlx4_ib_db *db) | |
128 | { | |
129 | int o; | |
130 | int i; | |
131 | ||
132 | mutex_lock(&dev->pgdir_mutex); | |
133 | ||
134 | o = db->order; | |
135 | i = db->index; | |
136 | ||
137 | if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) { | |
138 | clear_bit(i ^ 1, db->u.pgdir->order0); | |
139 | ++o; | |
140 | } | |
141 | ||
142 | i >>= o; | |
143 | set_bit(i, db->u.pgdir->bits[o]); | |
144 | ||
145 | if (bitmap_full(db->u.pgdir->order1, MLX4_IB_DB_PER_PAGE / 2)) { | |
146 | dma_free_coherent(dev->ib_dev.dma_device, PAGE_SIZE, | |
147 | db->u.pgdir->db_page, db->u.pgdir->db_dma); | |
148 | list_del(&db->u.pgdir->list); | |
149 | kfree(db->u.pgdir); | |
150 | } | |
151 | ||
152 | mutex_unlock(&dev->pgdir_mutex); | |
153 | } | |
154 | ||
155 | struct mlx4_ib_user_db_page { | |
156 | struct list_head list; | |
157 | struct ib_umem *umem; | |
158 | unsigned long user_virt; | |
159 | int refcnt; | |
160 | }; | |
161 | ||
162 | int mlx4_ib_db_map_user(struct mlx4_ib_ucontext *context, unsigned long virt, | |
163 | struct mlx4_ib_db *db) | |
164 | { | |
165 | struct mlx4_ib_user_db_page *page; | |
166 | struct ib_umem_chunk *chunk; | |
167 | int err = 0; | |
168 | ||
169 | mutex_lock(&context->db_page_mutex); | |
170 | ||
171 | list_for_each_entry(page, &context->db_page_list, list) | |
172 | if (page->user_virt == (virt & PAGE_MASK)) | |
173 | goto found; | |
174 | ||
175 | page = kmalloc(sizeof *page, GFP_KERNEL); | |
176 | if (!page) { | |
177 | err = -ENOMEM; | |
178 | goto out; | |
179 | } | |
180 | ||
181 | page->user_virt = (virt & PAGE_MASK); | |
182 | page->refcnt = 0; | |
183 | page->umem = ib_umem_get(&context->ibucontext, virt & PAGE_MASK, | |
184 | PAGE_SIZE, 0); | |
185 | if (IS_ERR(page->umem)) { | |
186 | err = PTR_ERR(page->umem); | |
187 | kfree(page); | |
188 | goto out; | |
189 | } | |
190 | ||
191 | list_add(&page->list, &context->db_page_list); | |
192 | ||
193 | found: | |
194 | chunk = list_entry(page->umem->chunk_list.next, struct ib_umem_chunk, list); | |
195 | db->dma = sg_dma_address(chunk->page_list) + (virt & ~PAGE_MASK); | |
196 | db->u.user_page = page; | |
197 | ++page->refcnt; | |
198 | ||
199 | out: | |
200 | mutex_unlock(&context->db_page_mutex); | |
201 | ||
202 | return err; | |
203 | } | |
204 | ||
205 | void mlx4_ib_db_unmap_user(struct mlx4_ib_ucontext *context, struct mlx4_ib_db *db) | |
206 | { | |
207 | mutex_lock(&context->db_page_mutex); | |
208 | ||
209 | if (!--db->u.user_page->refcnt) { | |
210 | list_del(&db->u.user_page->list); | |
211 | ib_umem_release(db->u.user_page->umem); | |
212 | kfree(db->u.user_page); | |
213 | } | |
214 | ||
215 | mutex_unlock(&context->db_page_mutex); | |
216 | } |