1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. 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/mm.h>
36 #include <linux/export.h>
37 #include <linux/bitmap.h>
38 #include <linux/dma-mapping.h>
39 #include <linux/vmalloc.h>
40 #include <linux/mlx5/driver.h>
41 
42 #include "mlx5_core.h"
43 
44 /* Handling for queue buffers -- we allocate a bunch of memory and
45  * register it in a memory region at HCA virtual address 0.
46  */
47 
48 static void *mlx5_dma_zalloc_coherent_node(struct mlx5_core_dev *dev,
49 					   size_t size, dma_addr_t *dma_handle,
50 					   int node)
51 {
52 	struct mlx5_priv *priv = &dev->priv;
53 	int original_node;
54 	void *cpu_handle;
55 
56 	mutex_lock(&priv->alloc_mutex);
57 	original_node = dev_to_node(&dev->pdev->dev);
58 	set_dev_node(&dev->pdev->dev, node);
59 	cpu_handle = dma_zalloc_coherent(&dev->pdev->dev, size,
60 					 dma_handle, GFP_KERNEL);
61 	set_dev_node(&dev->pdev->dev, original_node);
62 	mutex_unlock(&priv->alloc_mutex);
63 	return cpu_handle;
64 }
65 
66 int mlx5_buf_alloc_node(struct mlx5_core_dev *dev, int size,
67 			struct mlx5_buf *buf, int node)
68 {
69 	dma_addr_t t;
70 
71 	buf->size = size;
72 	buf->npages       = 1;
73 	buf->page_shift   = (u8)get_order(size) + PAGE_SHIFT;
74 	buf->direct.buf   = mlx5_dma_zalloc_coherent_node(dev, size,
75 							  &t, node);
76 	if (!buf->direct.buf)
77 		return -ENOMEM;
78 
79 	buf->direct.map = t;
80 
81 	while (t & ((1 << buf->page_shift) - 1)) {
82 		--buf->page_shift;
83 		buf->npages *= 2;
84 	}
85 
86 	return 0;
87 }
88 
89 int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, struct mlx5_buf *buf)
90 {
91 	return mlx5_buf_alloc_node(dev, size, buf, dev->priv.numa_node);
92 }
93 EXPORT_SYMBOL_GPL(mlx5_buf_alloc);
94 
95 void mlx5_buf_free(struct mlx5_core_dev *dev, struct mlx5_buf *buf)
96 {
97 	dma_free_coherent(&dev->pdev->dev, buf->size, buf->direct.buf,
98 			  buf->direct.map);
99 }
100 EXPORT_SYMBOL_GPL(mlx5_buf_free);
101 
102 static struct mlx5_db_pgdir *mlx5_alloc_db_pgdir(struct mlx5_core_dev *dev,
103 						 int node)
104 {
105 	struct mlx5_db_pgdir *pgdir;
106 
107 	pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
108 	if (!pgdir)
109 		return NULL;
110 
111 	bitmap_fill(pgdir->bitmap, MLX5_DB_PER_PAGE);
112 
113 	pgdir->db_page = mlx5_dma_zalloc_coherent_node(dev, PAGE_SIZE,
114 						       &pgdir->db_dma, node);
115 	if (!pgdir->db_page) {
116 		kfree(pgdir);
117 		return NULL;
118 	}
119 
120 	return pgdir;
121 }
122 
123 static int mlx5_alloc_db_from_pgdir(struct mlx5_db_pgdir *pgdir,
124 				    struct mlx5_db *db)
125 {
126 	int offset;
127 	int i;
128 
129 	i = find_first_bit(pgdir->bitmap, MLX5_DB_PER_PAGE);
130 	if (i >= MLX5_DB_PER_PAGE)
131 		return -ENOMEM;
132 
133 	__clear_bit(i, pgdir->bitmap);
134 
135 	db->u.pgdir = pgdir;
136 	db->index   = i;
137 	offset = db->index * L1_CACHE_BYTES;
138 	db->db      = pgdir->db_page + offset / sizeof(*pgdir->db_page);
139 	db->dma     = pgdir->db_dma  + offset;
140 
141 	db->db[0] = 0;
142 	db->db[1] = 0;
143 
144 	return 0;
145 }
146 
147 int mlx5_db_alloc_node(struct mlx5_core_dev *dev, struct mlx5_db *db, int node)
148 {
149 	struct mlx5_db_pgdir *pgdir;
150 	int ret = 0;
151 
152 	mutex_lock(&dev->priv.pgdir_mutex);
153 
154 	list_for_each_entry(pgdir, &dev->priv.pgdir_list, list)
155 		if (!mlx5_alloc_db_from_pgdir(pgdir, db))
156 			goto out;
157 
158 	pgdir = mlx5_alloc_db_pgdir(dev, node);
159 	if (!pgdir) {
160 		ret = -ENOMEM;
161 		goto out;
162 	}
163 
164 	list_add(&pgdir->list, &dev->priv.pgdir_list);
165 
166 	/* This should never fail -- we just allocated an empty page: */
167 	WARN_ON(mlx5_alloc_db_from_pgdir(pgdir, db));
168 
169 out:
170 	mutex_unlock(&dev->priv.pgdir_mutex);
171 
172 	return ret;
173 }
174 EXPORT_SYMBOL_GPL(mlx5_db_alloc_node);
175 
176 int mlx5_db_alloc(struct mlx5_core_dev *dev, struct mlx5_db *db)
177 {
178 	return mlx5_db_alloc_node(dev, db, dev->priv.numa_node);
179 }
180 EXPORT_SYMBOL_GPL(mlx5_db_alloc);
181 
182 void mlx5_db_free(struct mlx5_core_dev *dev, struct mlx5_db *db)
183 {
184 	mutex_lock(&dev->priv.pgdir_mutex);
185 
186 	__set_bit(db->index, db->u.pgdir->bitmap);
187 
188 	if (bitmap_full(db->u.pgdir->bitmap, MLX5_DB_PER_PAGE)) {
189 		dma_free_coherent(&(dev->pdev->dev), PAGE_SIZE,
190 				  db->u.pgdir->db_page, db->u.pgdir->db_dma);
191 		list_del(&db->u.pgdir->list);
192 		kfree(db->u.pgdir);
193 	}
194 
195 	mutex_unlock(&dev->priv.pgdir_mutex);
196 }
197 EXPORT_SYMBOL_GPL(mlx5_db_free);
198 
199 
200 void mlx5_fill_page_array(struct mlx5_buf *buf, __be64 *pas)
201 {
202 	u64 addr;
203 	int i;
204 
205 	for (i = 0; i < buf->npages; i++) {
206 		addr = buf->direct.map + (i << buf->page_shift);
207 
208 		pas[i] = cpu_to_be64(addr);
209 	}
210 }
211 EXPORT_SYMBOL_GPL(mlx5_fill_page_array);
212