Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
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linux
1/*
2 * Copyright (c) 2006, 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/errno.h>
34#include <linux/slab.h>
35#include <linux/bitmap.h>
36#include <linux/dma-mapping.h>
37
38#include "mlx4.h"
39
40u32 mlx4_bitmap_alloc(struct mlx4_bitmap *bitmap)
41{
42 u32 obj;
43
44 spin_lock(&bitmap->lock);
45
46 obj = find_next_zero_bit(bitmap->table, bitmap->max, bitmap->last);
47 if (obj >= bitmap->max) {
48 bitmap->top = (bitmap->top + bitmap->max) & bitmap->mask;
49 obj = find_first_zero_bit(bitmap->table, bitmap->max);
50 }
51
52 if (obj < bitmap->max) {
53 set_bit(obj, bitmap->table);
54 bitmap->last = (obj + 1) & (bitmap->max - 1);
55 obj |= bitmap->top;
56 } else
57 obj = -1;
58
59 spin_unlock(&bitmap->lock);
60
61 return obj;
62}
63
64void mlx4_bitmap_free(struct mlx4_bitmap *bitmap, u32 obj)
65{
66 obj &= bitmap->max - 1;
67
68 spin_lock(&bitmap->lock);
69 clear_bit(obj, bitmap->table);
70 bitmap->last = min(bitmap->last, obj);
71 bitmap->top = (bitmap->top + bitmap->max) & bitmap->mask;
72 spin_unlock(&bitmap->lock);
73}
74
75int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask, u32 reserved)
76{
77 int i;
78
79 /* num must be a power of 2 */
80 if (num != roundup_pow_of_two(num))
81 return -EINVAL;
82
83 bitmap->last = 0;
84 bitmap->top = 0;
85 bitmap->max = num;
86 bitmap->mask = mask;
87 spin_lock_init(&bitmap->lock);
88 bitmap->table = kzalloc(BITS_TO_LONGS(num) * sizeof (long), GFP_KERNEL);
89 if (!bitmap->table)
90 return -ENOMEM;
91
92 for (i = 0; i < reserved; ++i)
93 set_bit(i, bitmap->table);
94
95 return 0;
96}
97
98void mlx4_bitmap_cleanup(struct mlx4_bitmap *bitmap)
99{
100 kfree(bitmap->table);
101}
102
103/*
104 * Handling for queue buffers -- we allocate a bunch of memory and
105 * register it in a memory region at HCA virtual address 0. If the
106 * requested size is > max_direct, we split the allocation into
107 * multiple pages, so we don't require too much contiguous memory.
108 */
109
110int mlx4_buf_alloc(struct mlx4_dev *dev, int size, int max_direct,
111 struct mlx4_buf *buf)
112{
113 dma_addr_t t;
114
115 if (size <= max_direct) {
116 buf->nbufs = 1;
117 buf->npages = 1;
118 buf->page_shift = get_order(size) + PAGE_SHIFT;
119 buf->u.direct.buf = dma_alloc_coherent(&dev->pdev->dev,
120 size, &t, GFP_KERNEL);
121 if (!buf->u.direct.buf)
122 return -ENOMEM;
123
124 buf->u.direct.map = t;
125
126 while (t & ((1 << buf->page_shift) - 1)) {
127 --buf->page_shift;
128 buf->npages *= 2;
129 }
130
131 memset(buf->u.direct.buf, 0, size);
132 } else {
133 int i;
134
135 buf->nbufs = (size + PAGE_SIZE - 1) / PAGE_SIZE;
136 buf->npages = buf->nbufs;
137 buf->page_shift = PAGE_SHIFT;
138 buf->u.page_list = kzalloc(buf->nbufs * sizeof *buf->u.page_list,
139 GFP_KERNEL);
140 if (!buf->u.page_list)
141 return -ENOMEM;
142
143 for (i = 0; i < buf->nbufs; ++i) {
144 buf->u.page_list[i].buf =
145 dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
146 &t, GFP_KERNEL);
147 if (!buf->u.page_list[i].buf)
148 goto err_free;
149
150 buf->u.page_list[i].map = t;
151
152 memset(buf->u.page_list[i].buf, 0, PAGE_SIZE);
153 }
154 }
155
156 return 0;
157
158err_free:
159 mlx4_buf_free(dev, size, buf);
160
161 return -ENOMEM;
162}
163EXPORT_SYMBOL_GPL(mlx4_buf_alloc);
164
165void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf)
166{
167 int i;
168
169 if (buf->nbufs == 1)
170 dma_free_coherent(&dev->pdev->dev, size, buf->u.direct.buf,
171 buf->u.direct.map);
172 else {
173 for (i = 0; i < buf->nbufs; ++i)
174 dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
175 buf->u.page_list[i].buf,
176 buf->u.page_list[i].map);
177 kfree(buf->u.page_list);
178 }
179}
180EXPORT_SYMBOL_GPL(mlx4_buf_free);