aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/infiniband/hw/amso1100/c2_alloc.c
blob: d4f5f5d42e90e36bb417b9f613933f4c5acf0ee1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
/*
 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/errno.h>
#include <linux/bitmap.h>

#include "c2.h"

static int c2_alloc_mqsp_chunk(struct c2_dev *c2dev, gfp_t gfp_mask,
			       struct sp_chunk **head)
{
	int i;
	struct sp_chunk *new_head;
	dma_addr_t dma_addr;

	new_head = dma_alloc_coherent(&c2dev->pcidev->dev, PAGE_SIZE,
				      &dma_addr, gfp_mask);
	if (new_head == NULL)
		return -ENOMEM;

	new_head->dma_addr = dma_addr;
	pci_unmap_addr_set(new_head, mapping, new_head->dma_addr);

	new_head->next = NULL;
	new_head->head = 0;

	/* build list where each index is the next free slot */
	for (i = 0;
	     i < (PAGE_SIZE - sizeof(struct sp_chunk) -
		  sizeof(u16)) / sizeof(u16) - 1;
	     i++) {
		new_head->shared_ptr[i] = i + 1;
	}
	/* terminate list */
	new_head->shared_ptr[i] = 0xFFFF;

	*head = new_head;
	return 0;
}

int c2_init_mqsp_pool(struct c2_dev *c2dev, gfp_t gfp_mask,
		      struct sp_chunk **root)
{
	return c2_alloc_mqsp_chunk(c2dev, gfp_mask, root);
}

void c2_free_mqsp_pool(struct c2_dev *c2dev, struct sp_chunk *root)
{
	struct sp_chunk *next;

	while (root) {
		next = root->next;
		dma_free_coherent(&c2dev->pcidev->dev, PAGE_SIZE, root,
				  pci_unmap_addr(root, mapping));
		root = next;
	}
}

__be16 *c2_alloc_mqsp(struct c2_dev *c2dev, struct sp_chunk *head,
		      dma_addr_t *dma_addr, gfp_t gfp_mask)
{
	u16 mqsp;

	while (head) {
		mqsp = head->head;
		if (mqsp != 0xFFFF) {
			head->head = head->shared_ptr[mqsp];
			break;
		} else if (head->next == NULL) {
			if (c2_alloc_mqsp_chunk(c2dev, gfp_mask, &head->next) ==
			    0) {
				head = head->next;
				mqsp = head->head;
				head->head = head->shared_ptr[mqsp];
				break;
			} else
				return NULL;
		} else
			head = head->next;
	}
	if (head) {
		*dma_addr = head->dma_addr +
			    ((unsigned long) &(head->shared_ptr[mqsp]) -
			     (unsigned long) head);
		pr_debug("%s addr %p dma_addr %llx\n", __func__,
			 &(head->shared_ptr[mqsp]), (unsigned long long) *dma_addr);
		return (__force __be16 *) &(head->shared_ptr[mqsp]);
	}
	return NULL;
}

void c2_free_mqsp(__be16 *mqsp)
{
	struct sp_chunk *head;
	u16 idx;

	/* The chunk containing this ptr begins at the page boundary */
	head = (struct sp_chunk *) ((unsigned long) mqsp & PAGE_MASK);

	/* Link head to new mqsp */
	*mqsp = (__force __be16) head->head;

	/* Compute the shared_ptr index */
	idx = ((unsigned long) mqsp & ~PAGE_MASK) >> 1;
	idx -= (unsigned long) &(((struct sp_chunk *) 0)->shared_ptr[0]) >> 1;

	/* Point this index at the head */
	head->shared_ptr[idx] = head->head;

	/* Point head at this index */
	head->head = idx;
}