kernel/drivers/net/ethernet/mellanox/mlx5/core/alloc.c

   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.  If the
  46  * requested size is > max_direct, we split the allocation into
  47  * multiple pages, so we don't require too much contiguous memory.
  48  */
  49
  50 int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, int max_direct,
  51                    struct mlx5_buf *buf)
  52 {
  53         dma_addr_t t;
  54
  55         buf->size = size;
  56         if (size <= max_direct) {
  57                 buf->nbufs        = 1;
  58                 buf->npages       = 1;
  59                 buf->page_shift   = (u8)get_order(size) + PAGE_SHIFT;
  60                 buf->direct.buf   = dma_zalloc_coherent(&dev->pdev->dev,
  61                                                         size, &t, GFP_KERNEL);
  62                 if (!buf->direct.buf)
  63                         return -ENOMEM;
  64
  65                 buf->direct.map = t;
  66
  67                 while (t & ((1 << buf->page_shift) - 1)) {
  68                         --buf->page_shift;
  69                         buf->npages *= 2;
  70                 }
  71         } else {
  72                 int i;
  73
  74                 buf->direct.buf  = NULL;
  75                 buf->nbufs       = (size + PAGE_SIZE - 1) / PAGE_SIZE;
  76                 buf->npages      = buf->nbufs;
  77                 buf->page_shift  = PAGE_SHIFT;
  78                 buf->page_list   = kcalloc(buf->nbufs, sizeof(*buf->page_list),
  79                                            GFP_KERNEL);
  80                 if (!buf->page_list)
  81                         return -ENOMEM;
  82
  83                 for (i = 0; i < buf->nbufs; i++) {
  84                         buf->page_list[i].buf =
  85                                 dma_zalloc_coherent(&dev->pdev->dev, PAGE_SIZE,
  86                                                     &t, GFP_KERNEL);
  87                         if (!buf->page_list[i].buf)
  88                                 goto err_free;
  89
  90                         buf->page_list[i].map = t;
  91                 }
  92
  93                 if (BITS_PER_LONG == 64) {
  94                         struct page **pages;
  95                         pages = kmalloc(sizeof(*pages) * buf->nbufs, GFP_KERNEL);
  96                         if (!pages)
  97                                 goto err_free;
  98                         for (i = 0; i < buf->nbufs; i++)
  99                                 pages[i] = virt_to_page(buf->page_list[i].buf);
 100                         buf->direct.buf = vmap(pages, buf->nbufs, VM_MAP, PAGE_KERNEL);
 101                         kfree(pages);
 102                         if (!buf->direct.buf)
 103                                 goto err_free;
 104                 }
 105         }
 106
 107         return 0;
 108
 109 err_free:
 110         mlx5_buf_free(dev, buf);
 111
 112         return -ENOMEM;
 113 }
 114 EXPORT_SYMBOL_GPL(mlx5_buf_alloc);
 115
 116 void mlx5_buf_free(struct mlx5_core_dev *dev, struct mlx5_buf *buf)
 117 {
 118         int i;
 119
 120         if (buf->nbufs == 1)
 121                 dma_free_coherent(&dev->pdev->dev, buf->size, buf->direct.buf,
 122                                   buf->direct.map);
 123         else {
 124                 if (BITS_PER_LONG == 64)
 125                         vunmap(buf->direct.buf);
 126
 127                 for (i = 0; i < buf->nbufs; i++)
 128                         if (buf->page_list[i].buf)
 129                                 dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
 130                                                   buf->page_list[i].buf,
 131                                                   buf->page_list[i].map);
 132                 kfree(buf->page_list);
 133         }
 134 }
 135 EXPORT_SYMBOL_GPL(mlx5_buf_free);
 136
 137 static struct mlx5_db_pgdir *mlx5_alloc_db_pgdir(struct device *dma_device)
 138 {
 139         struct mlx5_db_pgdir *pgdir;
 140
 141         pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
 142         if (!pgdir)
 143                 return NULL;
 144
 145         bitmap_fill(pgdir->bitmap, MLX5_DB_PER_PAGE);
 146         pgdir->db_page = dma_alloc_coherent(dma_device, PAGE_SIZE,
 147                                             &pgdir->db_dma, GFP_KERNEL);
 148         if (!pgdir->db_page) {
 149                 kfree(pgdir);
 150                 return NULL;
 151         }
 152
 153         return pgdir;
 154 }
 155
 156 static int mlx5_alloc_db_from_pgdir(struct mlx5_db_pgdir *pgdir,
 157                                     struct mlx5_db *db)
 158 {
 159         int offset;
 160         int i;
 161
 162         i = find_first_bit(pgdir->bitmap, MLX5_DB_PER_PAGE);
 163         if (i >= MLX5_DB_PER_PAGE)
 164                 return -ENOMEM;
 165
 166         __clear_bit(i, pgdir->bitmap);
 167
 168         db->u.pgdir = pgdir;
 169         db->index   = i;
 170         offset = db->index * L1_CACHE_BYTES;
 171         db->db      = pgdir->db_page + offset / sizeof(*pgdir->db_page);
 172         db->dma     = pgdir->db_dma  + offset;
 173
 174         db->db[0] = 0;
 175         db->db[1] = 0;
 176
 177         return 0;
 178 }
 179
 180 int mlx5_db_alloc(struct mlx5_core_dev *dev, struct mlx5_db *db)
 181 {
 182         struct mlx5_db_pgdir *pgdir;
 183         int ret = 0;
 184
 185         mutex_lock(&dev->priv.pgdir_mutex);
 186
 187         list_for_each_entry(pgdir, &dev->priv.pgdir_list, list)
 188                 if (!mlx5_alloc_db_from_pgdir(pgdir, db))
 189                         goto out;
 190
 191         pgdir = mlx5_alloc_db_pgdir(&(dev->pdev->dev));
 192         if (!pgdir) {
 193                 ret = -ENOMEM;
 194                 goto out;
 195         }
 196
 197         list_add(&pgdir->list, &dev->priv.pgdir_list);
 198
 199         /* This should never fail -- we just allocated an empty page: */
 200         WARN_ON(mlx5_alloc_db_from_pgdir(pgdir, db));
 201
 202 out:
 203         mutex_unlock(&dev->priv.pgdir_mutex);
 204
 205         return ret;
 206 }
 207 EXPORT_SYMBOL_GPL(mlx5_db_alloc);
 208
 209 void mlx5_db_free(struct mlx5_core_dev *dev, struct mlx5_db *db)
 210 {
 211         mutex_lock(&dev->priv.pgdir_mutex);
 212
 213         __set_bit(db->index, db->u.pgdir->bitmap);
 214
 215         if (bitmap_full(db->u.pgdir->bitmap, MLX5_DB_PER_PAGE)) {
 216                 dma_free_coherent(&(dev->pdev->dev), PAGE_SIZE,
 217                                   db->u.pgdir->db_page, db->u.pgdir->db_dma);
 218                 list_del(&db->u.pgdir->list);
 219                 kfree(db->u.pgdir);
 220         }
 221
 222         mutex_unlock(&dev->priv.pgdir_mutex);
 223 }
 224 EXPORT_SYMBOL_GPL(mlx5_db_free);
 225
 226
 227 void mlx5_fill_page_array(struct mlx5_buf *buf, __be64 *pas)
 228 {
 229         u64 addr;
 230         int i;
 231
 232         for (i = 0; i < buf->npages; i++) {
 233                 if (buf->nbufs == 1)
 234                         addr = buf->direct.map + (i << buf->page_shift);
 235                 else
 236                         addr = buf->page_list[i].map;
 237
 238                 pas[i] = cpu_to_be64(addr);
 239         }
 240 }
 241 EXPORT_SYMBOL_GPL(mlx5_fill_page_array);