1 /* SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) */
2 /*
3 * Copyright (c) 2017 Hisilicon Limited.
4 * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved.
5 */
6
7 #include <rdma/ib_umem.h>
8 #include "hns_roce_device.h"
9
hns_roce_db_map_user(struct hns_roce_ucontext * context,unsigned long virt,struct hns_roce_db * db)10 int hns_roce_db_map_user(struct hns_roce_ucontext *context, unsigned long virt,
11 struct hns_roce_db *db)
12 {
13 unsigned long page_addr = virt & PAGE_MASK;
14 struct hns_roce_user_db_page *page;
15 unsigned int offset;
16 int ret = 0;
17
18 mutex_lock(&context->page_mutex);
19
20 list_for_each_entry(page, &context->page_list, list)
21 if (page->user_virt == page_addr)
22 goto found;
23
24 page = kmalloc(sizeof(*page), GFP_KERNEL);
25 if (!page) {
26 ret = -ENOMEM;
27 goto out;
28 }
29
30 refcount_set(&page->refcount, 1);
31 page->user_virt = page_addr;
32 page->umem = ib_umem_get(context->ibucontext.device, page_addr,
33 PAGE_SIZE, 0);
34 if (IS_ERR(page->umem)) {
35 ret = PTR_ERR(page->umem);
36 kfree(page);
37 goto out;
38 }
39
40 list_add(&page->list, &context->page_list);
41
42 found:
43 offset = virt - page_addr;
44 db->dma = sg_dma_address(page->umem->sgt_append.sgt.sgl) + offset;
45 db->virt_addr = sg_virt(page->umem->sgt_append.sgt.sgl) + offset;
46 db->u.user_page = page;
47 refcount_inc(&page->refcount);
48
49 out:
50 mutex_unlock(&context->page_mutex);
51
52 return ret;
53 }
54
hns_roce_db_unmap_user(struct hns_roce_ucontext * context,struct hns_roce_db * db)55 void hns_roce_db_unmap_user(struct hns_roce_ucontext *context,
56 struct hns_roce_db *db)
57 {
58 mutex_lock(&context->page_mutex);
59
60 refcount_dec(&db->u.user_page->refcount);
61 if (refcount_dec_if_one(&db->u.user_page->refcount)) {
62 list_del(&db->u.user_page->list);
63 ib_umem_release(db->u.user_page->umem);
64 kfree(db->u.user_page);
65 }
66
67 mutex_unlock(&context->page_mutex);
68 }
69
hns_roce_alloc_db_pgdir(struct device * dma_device)70 static struct hns_roce_db_pgdir *hns_roce_alloc_db_pgdir(
71 struct device *dma_device)
72 {
73 struct hns_roce_db_pgdir *pgdir;
74
75 pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
76 if (!pgdir)
77 return NULL;
78
79 bitmap_fill(pgdir->order1,
80 HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT);
81 pgdir->bits[0] = pgdir->order0;
82 pgdir->bits[1] = pgdir->order1;
83 pgdir->page = dma_alloc_coherent(dma_device, PAGE_SIZE,
84 &pgdir->db_dma, GFP_KERNEL);
85 if (!pgdir->page) {
86 kfree(pgdir);
87 return NULL;
88 }
89
90 return pgdir;
91 }
92
hns_roce_alloc_db_from_pgdir(struct hns_roce_db_pgdir * pgdir,struct hns_roce_db * db,int order)93 static int hns_roce_alloc_db_from_pgdir(struct hns_roce_db_pgdir *pgdir,
94 struct hns_roce_db *db, int order)
95 {
96 unsigned long o;
97 unsigned long i;
98
99 for (o = order; o <= 1; ++o) {
100 i = find_first_bit(pgdir->bits[o], HNS_ROCE_DB_PER_PAGE >> o);
101 if (i < HNS_ROCE_DB_PER_PAGE >> o)
102 goto found;
103 }
104
105 return -ENOMEM;
106
107 found:
108 clear_bit(i, pgdir->bits[o]);
109
110 i <<= o;
111
112 if (o > order)
113 set_bit(i ^ 1, pgdir->bits[order]);
114
115 db->u.pgdir = pgdir;
116 db->index = i;
117 db->db_record = pgdir->page + db->index;
118 db->dma = pgdir->db_dma + db->index * HNS_ROCE_DB_UNIT_SIZE;
119 db->order = order;
120
121 return 0;
122 }
123
hns_roce_alloc_db(struct hns_roce_dev * hr_dev,struct hns_roce_db * db,int order)124 int hns_roce_alloc_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db,
125 int order)
126 {
127 struct hns_roce_db_pgdir *pgdir;
128 int ret = 0;
129
130 mutex_lock(&hr_dev->pgdir_mutex);
131
132 list_for_each_entry(pgdir, &hr_dev->pgdir_list, list)
133 if (!hns_roce_alloc_db_from_pgdir(pgdir, db, order))
134 goto out;
135
136 pgdir = hns_roce_alloc_db_pgdir(hr_dev->dev);
137 if (!pgdir) {
138 ret = -ENOMEM;
139 goto out;
140 }
141
142 list_add(&pgdir->list, &hr_dev->pgdir_list);
143
144 /* This should never fail -- we just allocated an empty page: */
145 WARN_ON(hns_roce_alloc_db_from_pgdir(pgdir, db, order));
146
147 out:
148 mutex_unlock(&hr_dev->pgdir_mutex);
149
150 return ret;
151 }
152
hns_roce_free_db(struct hns_roce_dev * hr_dev,struct hns_roce_db * db)153 void hns_roce_free_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db)
154 {
155 unsigned long o;
156 unsigned long i;
157
158 mutex_lock(&hr_dev->pgdir_mutex);
159
160 o = db->order;
161 i = db->index;
162
163 if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) {
164 clear_bit(i ^ 1, db->u.pgdir->order0);
165 ++o;
166 }
167
168 i >>= o;
169 set_bit(i, db->u.pgdir->bits[o]);
170
171 if (bitmap_full(db->u.pgdir->order1,
172 HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT)) {
173 dma_free_coherent(hr_dev->dev, PAGE_SIZE, db->u.pgdir->page,
174 db->u.pgdir->db_dma);
175 list_del(&db->u.pgdir->list);
176 kfree(db->u.pgdir);
177 }
178
179 mutex_unlock(&hr_dev->pgdir_mutex);
180 }
181