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 struct mlx5_db_pgdir {
45 	struct list_head	list;
46 	unsigned long	       *bitmap;
47 	__be32		       *db_page;
48 	dma_addr_t		db_dma;
49 };
50 
51 /* Handling for queue buffers -- we allocate a bunch of memory and
52  * register it in a memory region at HCA virtual address 0.
53  */
54 
55 static void *mlx5_dma_zalloc_coherent_node(struct mlx5_core_dev *dev,
56 					   size_t size, dma_addr_t *dma_handle,
57 					   int node)
58 {
59 	struct mlx5_priv *priv = &dev->priv;
60 	int original_node;
61 	void *cpu_handle;
62 
63 	mutex_lock(&priv->alloc_mutex);
64 	original_node = dev_to_node(&dev->pdev->dev);
65 	set_dev_node(&dev->pdev->dev, node);
66 	cpu_handle = dma_zalloc_coherent(&dev->pdev->dev, size,
67 					 dma_handle, GFP_KERNEL);
68 	set_dev_node(&dev->pdev->dev, original_node);
69 	mutex_unlock(&priv->alloc_mutex);
70 	return cpu_handle;
71 }
72 
73 int mlx5_buf_alloc_node(struct mlx5_core_dev *dev, int size,
74 			struct mlx5_buf *buf, int node)
75 {
76 	dma_addr_t t;
77 
78 	buf->size = size;
79 	buf->npages       = 1;
80 	buf->page_shift   = (u8)get_order(size) + PAGE_SHIFT;
81 	buf->direct.buf   = mlx5_dma_zalloc_coherent_node(dev, size,
82 							  &t, node);
83 	if (!buf->direct.buf)
84 		return -ENOMEM;
85 
86 	buf->direct.map = t;
87 
88 	while (t & ((1 << buf->page_shift) - 1)) {
89 		--buf->page_shift;
90 		buf->npages *= 2;
91 	}
92 
93 	return 0;
94 }
95 
96 int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, struct mlx5_buf *buf)
97 {
98 	return mlx5_buf_alloc_node(dev, size, buf, dev->priv.numa_node);
99 }
100 EXPORT_SYMBOL_GPL(mlx5_buf_alloc);
101 
102 void mlx5_buf_free(struct mlx5_core_dev *dev, struct mlx5_buf *buf)
103 {
104 	dma_free_coherent(&dev->pdev->dev, buf->size, buf->direct.buf,
105 			  buf->direct.map);
106 }
107 EXPORT_SYMBOL_GPL(mlx5_buf_free);
108 
109 int mlx5_frag_buf_alloc_node(struct mlx5_core_dev *dev, int size,
110 			     struct mlx5_frag_buf *buf, int node)
111 {
112 	int i;
113 
114 	buf->size = size;
115 	buf->npages = 1 << get_order(size);
116 	buf->page_shift = PAGE_SHIFT;
117 	buf->frags = kcalloc(buf->npages, sizeof(struct mlx5_buf_list),
118 			     GFP_KERNEL);
119 	if (!buf->frags)
120 		goto err_out;
121 
122 	for (i = 0; i < buf->npages; i++) {
123 		struct mlx5_buf_list *frag = &buf->frags[i];
124 		int frag_sz = min_t(int, size, PAGE_SIZE);
125 
126 		frag->buf = mlx5_dma_zalloc_coherent_node(dev, frag_sz,
127 							  &frag->map, node);
128 		if (!frag->buf)
129 			goto err_free_buf;
130 		if (frag->map & ((1 << buf->page_shift) - 1)) {
131 			dma_free_coherent(&dev->pdev->dev, frag_sz,
132 					  buf->frags[i].buf, buf->frags[i].map);
133 			mlx5_core_warn(dev, "unexpected map alignment: %pad, page_shift=%d\n",
134 				       &frag->map, buf->page_shift);
135 			goto err_free_buf;
136 		}
137 		size -= frag_sz;
138 	}
139 
140 	return 0;
141 
142 err_free_buf:
143 	while (i--)
144 		dma_free_coherent(&dev->pdev->dev, PAGE_SIZE, buf->frags[i].buf,
145 				  buf->frags[i].map);
146 	kfree(buf->frags);
147 err_out:
148 	return -ENOMEM;
149 }
150 
151 void mlx5_frag_buf_free(struct mlx5_core_dev *dev, struct mlx5_frag_buf *buf)
152 {
153 	int size = buf->size;
154 	int i;
155 
156 	for (i = 0; i < buf->npages; i++) {
157 		int frag_sz = min_t(int, size, PAGE_SIZE);
158 
159 		dma_free_coherent(&dev->pdev->dev, frag_sz, buf->frags[i].buf,
160 				  buf->frags[i].map);
161 		size -= frag_sz;
162 	}
163 	kfree(buf->frags);
164 }
165 
166 static struct mlx5_db_pgdir *mlx5_alloc_db_pgdir(struct mlx5_core_dev *dev,
167 						 int node)
168 {
169 	u32 db_per_page = PAGE_SIZE / cache_line_size();
170 	struct mlx5_db_pgdir *pgdir;
171 
172 	pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
173 	if (!pgdir)
174 		return NULL;
175 
176 	pgdir->bitmap = kcalloc(BITS_TO_LONGS(db_per_page),
177 				sizeof(unsigned long),
178 				GFP_KERNEL);
179 
180 	if (!pgdir->bitmap) {
181 		kfree(pgdir);
182 		return NULL;
183 	}
184 
185 	bitmap_fill(pgdir->bitmap, db_per_page);
186 
187 	pgdir->db_page = mlx5_dma_zalloc_coherent_node(dev, PAGE_SIZE,
188 						       &pgdir->db_dma, node);
189 	if (!pgdir->db_page) {
190 		kfree(pgdir->bitmap);
191 		kfree(pgdir);
192 		return NULL;
193 	}
194 
195 	return pgdir;
196 }
197 
198 static int mlx5_alloc_db_from_pgdir(struct mlx5_db_pgdir *pgdir,
199 				    struct mlx5_db *db)
200 {
201 	u32 db_per_page = PAGE_SIZE / cache_line_size();
202 	int offset;
203 	int i;
204 
205 	i = find_first_bit(pgdir->bitmap, db_per_page);
206 	if (i >= db_per_page)
207 		return -ENOMEM;
208 
209 	__clear_bit(i, pgdir->bitmap);
210 
211 	db->u.pgdir = pgdir;
212 	db->index   = i;
213 	offset = db->index * cache_line_size();
214 	db->db      = pgdir->db_page + offset / sizeof(*pgdir->db_page);
215 	db->dma     = pgdir->db_dma  + offset;
216 
217 	db->db[0] = 0;
218 	db->db[1] = 0;
219 
220 	return 0;
221 }
222 
223 int mlx5_db_alloc_node(struct mlx5_core_dev *dev, struct mlx5_db *db, int node)
224 {
225 	struct mlx5_db_pgdir *pgdir;
226 	int ret = 0;
227 
228 	mutex_lock(&dev->priv.pgdir_mutex);
229 
230 	list_for_each_entry(pgdir, &dev->priv.pgdir_list, list)
231 		if (!mlx5_alloc_db_from_pgdir(pgdir, db))
232 			goto out;
233 
234 	pgdir = mlx5_alloc_db_pgdir(dev, node);
235 	if (!pgdir) {
236 		ret = -ENOMEM;
237 		goto out;
238 	}
239 
240 	list_add(&pgdir->list, &dev->priv.pgdir_list);
241 
242 	/* This should never fail -- we just allocated an empty page: */
243 	WARN_ON(mlx5_alloc_db_from_pgdir(pgdir, db));
244 
245 out:
246 	mutex_unlock(&dev->priv.pgdir_mutex);
247 
248 	return ret;
249 }
250 EXPORT_SYMBOL_GPL(mlx5_db_alloc_node);
251 
252 int mlx5_db_alloc(struct mlx5_core_dev *dev, struct mlx5_db *db)
253 {
254 	return mlx5_db_alloc_node(dev, db, dev->priv.numa_node);
255 }
256 EXPORT_SYMBOL_GPL(mlx5_db_alloc);
257 
258 void mlx5_db_free(struct mlx5_core_dev *dev, struct mlx5_db *db)
259 {
260 	u32 db_per_page = PAGE_SIZE / cache_line_size();
261 
262 	mutex_lock(&dev->priv.pgdir_mutex);
263 
264 	__set_bit(db->index, db->u.pgdir->bitmap);
265 
266 	if (bitmap_full(db->u.pgdir->bitmap, db_per_page)) {
267 		dma_free_coherent(&(dev->pdev->dev), PAGE_SIZE,
268 				  db->u.pgdir->db_page, db->u.pgdir->db_dma);
269 		list_del(&db->u.pgdir->list);
270 		kfree(db->u.pgdir->bitmap);
271 		kfree(db->u.pgdir);
272 	}
273 
274 	mutex_unlock(&dev->priv.pgdir_mutex);
275 }
276 EXPORT_SYMBOL_GPL(mlx5_db_free);
277 
278 void mlx5_fill_page_array(struct mlx5_buf *buf, __be64 *pas)
279 {
280 	u64 addr;
281 	int i;
282 
283 	for (i = 0; i < buf->npages; i++) {
284 		addr = buf->direct.map + (i << buf->page_shift);
285 
286 		pas[i] = cpu_to_be64(addr);
287 	}
288 }
289 EXPORT_SYMBOL_GPL(mlx5_fill_page_array);
290 
291 void mlx5_fill_page_frag_array(struct mlx5_frag_buf *buf, __be64 *pas)
292 {
293 	int i;
294 
295 	for (i = 0; i < buf->npages; i++)
296 		pas[i] = cpu_to_be64(buf->frags[i].map);
297 }
298 EXPORT_SYMBOL_GPL(mlx5_fill_page_frag_array);
299