aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/infiniband/hw/hns/hns_roce_db.c
blob: 10af6958ab694de8f1b8fc7d889a3ad956d1d14f (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
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/* SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) */
/*
 * Copyright (c) 2017 Hisilicon Limited.
 * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved.
 */

#include <linux/platform_device.h>
#include <rdma/ib_umem.h>
#include "hns_roce_device.h"

int hns_roce_db_map_user(struct hns_roce_ucontext *context,
			 struct ib_udata *udata, unsigned long virt,
			 struct hns_roce_db *db)
{
	unsigned long page_addr = virt & PAGE_MASK;
	struct hns_roce_user_db_page *page;
	unsigned int offset;
	int ret = 0;

	mutex_lock(&context->page_mutex);

	list_for_each_entry(page, &context->page_list, list)
		if (page->user_virt == page_addr)
			goto found;

	page = kmalloc(sizeof(*page), GFP_KERNEL);
	if (!page) {
		ret = -ENOMEM;
		goto out;
	}

	refcount_set(&page->refcount, 1);
	page->user_virt = page_addr;
	page->umem = ib_umem_get(udata, page_addr, PAGE_SIZE, 0);
	if (IS_ERR(page->umem)) {
		ret = PTR_ERR(page->umem);
		kfree(page);
		goto out;
	}

	list_add(&page->list, &context->page_list);

found:
	offset = virt - page_addr;
	db->dma = sg_dma_address(page->umem->sg_head.sgl) + offset;
	db->virt_addr = sg_virt(page->umem->sg_head.sgl) + offset;
	db->u.user_page = page;
	refcount_inc(&page->refcount);

out:
	mutex_unlock(&context->page_mutex);

	return ret;
}

void hns_roce_db_unmap_user(struct hns_roce_ucontext *context,
			    struct hns_roce_db *db)
{
	mutex_lock(&context->page_mutex);

	refcount_dec(&db->u.user_page->refcount);
	if (refcount_dec_if_one(&db->u.user_page->refcount)) {
		list_del(&db->u.user_page->list);
		ib_umem_release(db->u.user_page->umem);
		kfree(db->u.user_page);
	}

	mutex_unlock(&context->page_mutex);
}

static struct hns_roce_db_pgdir *hns_roce_alloc_db_pgdir(
					struct device *dma_device)
{
	struct hns_roce_db_pgdir *pgdir;

	pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
	if (!pgdir)
		return NULL;

	bitmap_fill(pgdir->order1,
		    HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT);
	pgdir->bits[0] = pgdir->order0;
	pgdir->bits[1] = pgdir->order1;
	pgdir->page = dma_alloc_coherent(dma_device, PAGE_SIZE,
					 &pgdir->db_dma, GFP_KERNEL);
	if (!pgdir->page) {
		kfree(pgdir);
		return NULL;
	}

	return pgdir;
}

static int hns_roce_alloc_db_from_pgdir(struct hns_roce_db_pgdir *pgdir,
					struct hns_roce_db *db, int order)
{
	int o;
	int i;

	for (o = order; o <= 1; ++o) {
		i = find_first_bit(pgdir->bits[o], HNS_ROCE_DB_PER_PAGE >> o);
		if (i < HNS_ROCE_DB_PER_PAGE >> o)
			goto found;
	}

	return -ENOMEM;

found:
	clear_bit(i, pgdir->bits[o]);

	i <<= o;

	if (o > order)
		set_bit(i ^ 1, pgdir->bits[order]);

	db->u.pgdir	= pgdir;
	db->index	= i;
	db->db_record	= pgdir->page + db->index;
	db->dma		= pgdir->db_dma  + db->index * HNS_ROCE_DB_UNIT_SIZE;
	db->order	= order;

	return 0;
}

int hns_roce_alloc_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db,
		      int order)
{
	struct hns_roce_db_pgdir *pgdir;
	int ret = 0;

	mutex_lock(&hr_dev->pgdir_mutex);

	list_for_each_entry(pgdir, &hr_dev->pgdir_list, list)
		if (!hns_roce_alloc_db_from_pgdir(pgdir, db, order))
			goto out;

	pgdir = hns_roce_alloc_db_pgdir(hr_dev->dev);
	if (!pgdir) {
		ret = -ENOMEM;
		goto out;
	}

	list_add(&pgdir->list, &hr_dev->pgdir_list);

	/* This should never fail -- we just allocated an empty page: */
	WARN_ON(hns_roce_alloc_db_from_pgdir(pgdir, db, order));

out:
	mutex_unlock(&hr_dev->pgdir_mutex);

	return ret;
}

void hns_roce_free_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db)
{
	int o;
	int i;

	mutex_lock(&hr_dev->pgdir_mutex);

	o = db->order;
	i = db->index;

	if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) {
		clear_bit(i ^ 1, db->u.pgdir->order0);
		++o;
	}

	i >>= o;
	set_bit(i, db->u.pgdir->bits[o]);

	if (bitmap_full(db->u.pgdir->order1,
			HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT)) {
		dma_free_coherent(hr_dev->dev, PAGE_SIZE, db->u.pgdir->page,
				  db->u.pgdir->db_dma);
		list_del(&db->u.pgdir->list);
		kfree(db->u.pgdir);
	}

	mutex_unlock(&hr_dev->pgdir_mutex);
}