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 
mlx5_dma_zalloc_coherent_node(struct mlx5_core_dev * dev,size_t size,dma_addr_t * dma_handle,int node)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 device *device = mlx5_core_dma_dev(dev);
60 	struct mlx5_priv *priv = &dev->priv;
61 	int original_node;
62 	void *cpu_handle;
63 
64 	mutex_lock(&priv->alloc_mutex);
65 	original_node = dev_to_node(device);
66 	set_dev_node(device, node);
67 	cpu_handle = dma_alloc_coherent(device, size, dma_handle,
68 					GFP_KERNEL);
69 	set_dev_node(device, original_node);
70 	mutex_unlock(&priv->alloc_mutex);
71 	return cpu_handle;
72 }
73 
mlx5_frag_buf_alloc_node(struct mlx5_core_dev * dev,int size,struct mlx5_frag_buf * buf,int node)74 int mlx5_frag_buf_alloc_node(struct mlx5_core_dev *dev, int size,
75 			     struct mlx5_frag_buf *buf, int node)
76 {
77 	int i;
78 
79 	buf->size = size;
80 	buf->npages = DIV_ROUND_UP(size, PAGE_SIZE);
81 	buf->page_shift = PAGE_SHIFT;
82 	buf->frags = kcalloc(buf->npages, sizeof(struct mlx5_buf_list),
83 			     GFP_KERNEL);
84 	if (!buf->frags)
85 		goto err_out;
86 
87 	for (i = 0; i < buf->npages; i++) {
88 		struct mlx5_buf_list *frag = &buf->frags[i];
89 		int frag_sz = min_t(int, size, PAGE_SIZE);
90 
91 		frag->buf = mlx5_dma_zalloc_coherent_node(dev, frag_sz,
92 							  &frag->map, node);
93 		if (!frag->buf)
94 			goto err_free_buf;
95 		if (frag->map & ((1 << buf->page_shift) - 1)) {
96 			dma_free_coherent(mlx5_core_dma_dev(dev), frag_sz,
97 					  buf->frags[i].buf, buf->frags[i].map);
98 			mlx5_core_warn(dev, "unexpected map alignment: %pad, page_shift=%d\n",
99 				       &frag->map, buf->page_shift);
100 			goto err_free_buf;
101 		}
102 		size -= frag_sz;
103 	}
104 
105 	return 0;
106 
107 err_free_buf:
108 	while (i--)
109 		dma_free_coherent(mlx5_core_dma_dev(dev), PAGE_SIZE, buf->frags[i].buf,
110 				  buf->frags[i].map);
111 	kfree(buf->frags);
112 err_out:
113 	return -ENOMEM;
114 }
115 EXPORT_SYMBOL_GPL(mlx5_frag_buf_alloc_node);
116 
mlx5_frag_buf_free(struct mlx5_core_dev * dev,struct mlx5_frag_buf * buf)117 void mlx5_frag_buf_free(struct mlx5_core_dev *dev, struct mlx5_frag_buf *buf)
118 {
119 	int size = buf->size;
120 	int i;
121 
122 	for (i = 0; i < buf->npages; i++) {
123 		int frag_sz = min_t(int, size, PAGE_SIZE);
124 
125 		dma_free_coherent(mlx5_core_dma_dev(dev), frag_sz, buf->frags[i].buf,
126 				  buf->frags[i].map);
127 		size -= frag_sz;
128 	}
129 	kfree(buf->frags);
130 }
131 EXPORT_SYMBOL_GPL(mlx5_frag_buf_free);
132 
mlx5_alloc_db_pgdir(struct mlx5_core_dev * dev,int node)133 static struct mlx5_db_pgdir *mlx5_alloc_db_pgdir(struct mlx5_core_dev *dev,
134 						 int node)
135 {
136 	u32 db_per_page = PAGE_SIZE / cache_line_size();
137 	struct mlx5_db_pgdir *pgdir;
138 
139 	pgdir = kzalloc_node(sizeof(*pgdir), GFP_KERNEL, node);
140 	if (!pgdir)
141 		return NULL;
142 
143 	pgdir->bitmap = bitmap_zalloc_node(db_per_page, GFP_KERNEL, node);
144 	if (!pgdir->bitmap) {
145 		kfree(pgdir);
146 		return NULL;
147 	}
148 
149 	bitmap_fill(pgdir->bitmap, db_per_page);
150 
151 	pgdir->db_page = mlx5_dma_zalloc_coherent_node(dev, PAGE_SIZE,
152 						       &pgdir->db_dma, node);
153 	if (!pgdir->db_page) {
154 		bitmap_free(pgdir->bitmap);
155 		kfree(pgdir);
156 		return NULL;
157 	}
158 
159 	return pgdir;
160 }
161 
mlx5_alloc_db_from_pgdir(struct mlx5_db_pgdir * pgdir,struct mlx5_db * db)162 static int mlx5_alloc_db_from_pgdir(struct mlx5_db_pgdir *pgdir,
163 				    struct mlx5_db *db)
164 {
165 	u32 db_per_page = PAGE_SIZE / cache_line_size();
166 	int offset;
167 	int i;
168 
169 	i = find_first_bit(pgdir->bitmap, db_per_page);
170 	if (i >= db_per_page)
171 		return -ENOMEM;
172 
173 	__clear_bit(i, pgdir->bitmap);
174 
175 	db->u.pgdir = pgdir;
176 	db->index   = i;
177 	offset = db->index * cache_line_size();
178 	db->db      = pgdir->db_page + offset / sizeof(*pgdir->db_page);
179 	db->dma     = pgdir->db_dma  + offset;
180 
181 	db->db[0] = 0;
182 	db->db[1] = 0;
183 
184 	return 0;
185 }
186 
mlx5_db_alloc_node(struct mlx5_core_dev * dev,struct mlx5_db * db,int node)187 int mlx5_db_alloc_node(struct mlx5_core_dev *dev, struct mlx5_db *db, int node)
188 {
189 	struct mlx5_db_pgdir *pgdir;
190 	int ret = 0;
191 
192 	mutex_lock(&dev->priv.pgdir_mutex);
193 
194 	list_for_each_entry(pgdir, &dev->priv.pgdir_list, list)
195 		if (!mlx5_alloc_db_from_pgdir(pgdir, db))
196 			goto out;
197 
198 	pgdir = mlx5_alloc_db_pgdir(dev, node);
199 	if (!pgdir) {
200 		ret = -ENOMEM;
201 		goto out;
202 	}
203 
204 	list_add(&pgdir->list, &dev->priv.pgdir_list);
205 
206 	/* This should never fail -- we just allocated an empty page: */
207 	WARN_ON(mlx5_alloc_db_from_pgdir(pgdir, db));
208 
209 out:
210 	mutex_unlock(&dev->priv.pgdir_mutex);
211 
212 	return ret;
213 }
214 EXPORT_SYMBOL_GPL(mlx5_db_alloc_node);
215 
mlx5_db_free(struct mlx5_core_dev * dev,struct mlx5_db * db)216 void mlx5_db_free(struct mlx5_core_dev *dev, struct mlx5_db *db)
217 {
218 	u32 db_per_page = PAGE_SIZE / cache_line_size();
219 
220 	mutex_lock(&dev->priv.pgdir_mutex);
221 
222 	__set_bit(db->index, db->u.pgdir->bitmap);
223 
224 	if (bitmap_full(db->u.pgdir->bitmap, db_per_page)) {
225 		dma_free_coherent(mlx5_core_dma_dev(dev), PAGE_SIZE,
226 				  db->u.pgdir->db_page, db->u.pgdir->db_dma);
227 		list_del(&db->u.pgdir->list);
228 		bitmap_free(db->u.pgdir->bitmap);
229 		kfree(db->u.pgdir);
230 	}
231 
232 	mutex_unlock(&dev->priv.pgdir_mutex);
233 }
234 EXPORT_SYMBOL_GPL(mlx5_db_free);
235 
mlx5_fill_page_frag_array_perm(struct mlx5_frag_buf * buf,__be64 * pas,u8 perm)236 void mlx5_fill_page_frag_array_perm(struct mlx5_frag_buf *buf, __be64 *pas, u8 perm)
237 {
238 	int i;
239 
240 	WARN_ON(perm & 0xfc);
241 	for (i = 0; i < buf->npages; i++)
242 		pas[i] = cpu_to_be64(buf->frags[i].map | perm);
243 }
244 EXPORT_SYMBOL_GPL(mlx5_fill_page_frag_array_perm);
245 
mlx5_fill_page_frag_array(struct mlx5_frag_buf * buf,__be64 * pas)246 void mlx5_fill_page_frag_array(struct mlx5_frag_buf *buf, __be64 *pas)
247 {
248 	mlx5_fill_page_frag_array_perm(buf, pas, 0);
249 }
250 EXPORT_SYMBOL_GPL(mlx5_fill_page_frag_array);
251