drivers/net/mlx4/alloc.c

   1 /*
   2  * Copyright (c) 2006, 2007 Cisco Systems, Inc.  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/bitmap.h>
  36 #include <linux/dma-mapping.h>
  37
  38 #include "mlx4.h"
  39
  40 u32 mlx4_bitmap_alloc(struct mlx4_bitmap *bitmap)
  41 {
  42         u32 obj;
  43
  44         spin_lock(&bitmap->lock);
  45
  46         obj = find_next_zero_bit(bitmap->table, bitmap->max, bitmap->last);
  47         if (obj >= bitmap->max) {
  48                 bitmap->top = (bitmap->top + bitmap->max) & bitmap->mask;
  49                 obj = find_first_zero_bit(bitmap->table, bitmap->max);
  50         }
  51
  52         if (obj < bitmap->max) {
  53                 set_bit(obj, bitmap->table);
  54                 bitmap->last = (obj + 1) & (bitmap->max - 1);
  55                 obj |= bitmap->top;
  56         } else
  57                 obj = -1;
  58
  59         spin_unlock(&bitmap->lock);
  60
  61         return obj;
  62 }
  63
  64 void mlx4_bitmap_free(struct mlx4_bitmap *bitmap, u32 obj)
  65 {
  66         obj &= bitmap->max - 1;
  67
  68         spin_lock(&bitmap->lock);
  69         clear_bit(obj, bitmap->table);
  70         bitmap->last = min(bitmap->last, obj);
  71         bitmap->top = (bitmap->top + bitmap->max) & bitmap->mask;
  72         spin_unlock(&bitmap->lock);
  73 }
  74
  75 int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask, u32 reserved)
  76 {
  77         int i;
  78
  79         /* num must be a power of 2 */
  80         if (num != roundup_pow_of_two(num))
  81                 return -EINVAL;
  82
  83         bitmap->last = 0;
  84         bitmap->top  = 0;
  85         bitmap->max  = num;
  86         bitmap->mask = mask;
  87         spin_lock_init(&bitmap->lock);
  88         bitmap->table = kzalloc(BITS_TO_LONGS(num) * sizeof (long), GFP_KERNEL);
  89         if (!bitmap->table)
  90                 return -ENOMEM;
  91
  92         for (i = 0; i < reserved; ++i)
  93                 set_bit(i, bitmap->table);
  94
  95         return 0;
  96 }
  97
  98 void mlx4_bitmap_cleanup(struct mlx4_bitmap *bitmap)
  99 {
 100         kfree(bitmap->table);
 101 }
 102
 103 /*
 104  * Handling for queue buffers -- we allocate a bunch of memory and
 105  * register it in a memory region at HCA virtual address 0.  If the
 106  * requested size is > max_direct, we split the allocation into
 107  * multiple pages, so we don't require too much contiguous memory.
 108  */
 109
 110 int mlx4_buf_alloc(struct mlx4_dev *dev, int size, int max_direct,
 111                    struct mlx4_buf *buf)
 112 {
 113         dma_addr_t t;
 114
 115         if (size <= max_direct) {
 116                 buf->nbufs        = 1;
 117                 buf->npages       = 1;
 118                 buf->page_shift   = get_order(size) + PAGE_SHIFT;
 119                 buf->u.direct.buf = dma_alloc_coherent(&dev->pdev->dev,
 120                                                        size, &t, GFP_KERNEL);
 121                 if (!buf->u.direct.buf)
 122                         return -ENOMEM;
 123
 124                 buf->u.direct.map = t;
 125
 126                 while (t & ((1 << buf->page_shift) - 1)) {
 127                         --buf->page_shift;
 128                         buf->npages *= 2;
 129                 }
 130
 131                 memset(buf->u.direct.buf, 0, size);
 132         } else {
 133                 int i;
 134
 135                 buf->nbufs       = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 136                 buf->npages      = buf->nbufs;
 137                 buf->page_shift  = PAGE_SHIFT;
 138                 buf->u.page_list = kzalloc(buf->nbufs * sizeof *buf->u.page_list,
 139                                            GFP_KERNEL);
 140                 if (!buf->u.page_list)
 141                         return -ENOMEM;
 142
 143                 for (i = 0; i < buf->nbufs; ++i) {
 144                         buf->u.page_list[i].buf =
 145                                 dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
 146                                                    &t, GFP_KERNEL);
 147                         if (!buf->u.page_list[i].buf)
 148                                 goto err_free;
 149
 150                         buf->u.page_list[i].map = t;
 151
 152                         memset(buf->u.page_list[i].buf, 0, PAGE_SIZE);
 153                 }
 154         }
 155
 156         return 0;
 157
 158 err_free:
 159         mlx4_buf_free(dev, size, buf);
 160
 161         return -ENOMEM;
 162 }
 163 EXPORT_SYMBOL_GPL(mlx4_buf_alloc);
 164
 165 void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf)
 166 {
 167         int i;
 168
 169         if (buf->nbufs == 1)
 170                 dma_free_coherent(&dev->pdev->dev, size, buf->u.direct.buf,
 171                                   buf->u.direct.map);
 172         else {
 173                 for (i = 0; i < buf->nbufs; ++i)
 174                         dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
 175                                           buf->u.page_list[i].buf,
 176                                           buf->u.page_list[i].map);
 177                 kfree(buf->u.page_list);
 178         }
 179 }
 180 EXPORT_SYMBOL_GPL(mlx4_buf_free);