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.
  46  */
  47
  48 int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, struct mlx5_buf *buf)
  49 {
  50         dma_addr_t t;
  51
  52         buf->size = size;
  53         buf->npages       = 1;
  54         buf->page_shift   = (u8)get_order(size) + PAGE_SHIFT;
  55         buf->direct.buf   = dma_zalloc_coherent(&dev->pdev->dev,
  56                                                 size, &t, GFP_KERNEL);
  57         if (!buf->direct.buf)
  58                 return -ENOMEM;
  59
  60         buf->direct.map = t;
  61
  62         while (t & ((1 << buf->page_shift) - 1)) {
  63                 --buf->page_shift;
  64                 buf->npages *= 2;
  65         }
  66
  67         return 0;
  68 }
  69 EXPORT_SYMBOL_GPL(mlx5_buf_alloc);
  70
  71 void mlx5_buf_free(struct mlx5_core_dev *dev, struct mlx5_buf *buf)
  72 {
  73         dma_free_coherent(&dev->pdev->dev, buf->size, buf->direct.buf,
  74                           buf->direct.map);
  75 }
  76 EXPORT_SYMBOL_GPL(mlx5_buf_free);
  77
  78 static struct mlx5_db_pgdir *mlx5_alloc_db_pgdir(struct device *dma_device)
  79 {
  80         struct mlx5_db_pgdir *pgdir;
  81
  82         pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL);
  83         if (!pgdir)
  84                 return NULL;
  85
  86         bitmap_fill(pgdir->bitmap, MLX5_DB_PER_PAGE);
  87         pgdir->db_page = dma_alloc_coherent(dma_device, PAGE_SIZE,
  88                                             &pgdir->db_dma, GFP_KERNEL);
  89         if (!pgdir->db_page) {
  90                 kfree(pgdir);
  91                 return NULL;
  92         }
  93
  94         return pgdir;
  95 }
  96
  97 static int mlx5_alloc_db_from_pgdir(struct mlx5_db_pgdir *pgdir,
  98                                     struct mlx5_db *db)
  99 {
 100         int offset;
 101         int i;
 102
 103         i = find_first_bit(pgdir->bitmap, MLX5_DB_PER_PAGE);
 104         if (i >= MLX5_DB_PER_PAGE)
 105                 return -ENOMEM;
 106
 107         __clear_bit(i, pgdir->bitmap);
 108
 109         db->u.pgdir = pgdir;
 110         db->index   = i;
 111         offset = db->index * L1_CACHE_BYTES;
 112         db->db      = pgdir->db_page + offset / sizeof(*pgdir->db_page);
 113         db->dma     = pgdir->db_dma  + offset;
 114
 115         db->db[0] = 0;
 116         db->db[1] = 0;
 117
 118         return 0;
 119 }
 120
 121 int mlx5_db_alloc(struct mlx5_core_dev *dev, struct mlx5_db *db)
 122 {
 123         struct mlx5_db_pgdir *pgdir;
 124         int ret = 0;
 125
 126         mutex_lock(&dev->priv.pgdir_mutex);
 127
 128         list_for_each_entry(pgdir, &dev->priv.pgdir_list, list)
 129                 if (!mlx5_alloc_db_from_pgdir(pgdir, db))
 130                         goto out;
 131
 132         pgdir = mlx5_alloc_db_pgdir(&(dev->pdev->dev));
 133         if (!pgdir) {
 134                 ret = -ENOMEM;
 135                 goto out;
 136         }
 137
 138         list_add(&pgdir->list, &dev->priv.pgdir_list);
 139
 140         /* This should never fail -- we just allocated an empty page: */
 141         WARN_ON(mlx5_alloc_db_from_pgdir(pgdir, db));
 142
 143 out:
 144         mutex_unlock(&dev->priv.pgdir_mutex);
 145
 146         return ret;
 147 }
 148 EXPORT_SYMBOL_GPL(mlx5_db_alloc);
 149
 150 void mlx5_db_free(struct mlx5_core_dev *dev, struct mlx5_db *db)
 151 {
 152         mutex_lock(&dev->priv.pgdir_mutex);
 153
 154         __set_bit(db->index, db->u.pgdir->bitmap);
 155
 156         if (bitmap_full(db->u.pgdir->bitmap, MLX5_DB_PER_PAGE)) {
 157                 dma_free_coherent(&(dev->pdev->dev), PAGE_SIZE,
 158                                   db->u.pgdir->db_page, db->u.pgdir->db_dma);
 159                 list_del(&db->u.pgdir->list);
 160                 kfree(db->u.pgdir);
 161         }
 162
 163         mutex_unlock(&dev->priv.pgdir_mutex);
 164 }
 165 EXPORT_SYMBOL_GPL(mlx5_db_free);
 166
 167
 168 void mlx5_fill_page_array(struct mlx5_buf *buf, __be64 *pas)
 169 {
 170         u64 addr;
 171         int i;
 172
 173         for (i = 0; i < buf->npages; i++) {
 174                 addr = buf->direct.map + (i << buf->page_shift);
 175
 176                 pas[i] = cpu_to_be64(addr);
 177         }
 178 }
 179 EXPORT_SYMBOL_GPL(mlx5_fill_page_array);