drivers/infiniband/hw/mthca/mthca_allocator.c

   1 /*
   2  * Copyright (c) 2004 Topspin Communications.  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  * $Id: mthca_allocator.c 1349 2004-12-16 21:09:43Z roland $
  33  */
  34
  35 #include <linux/errno.h>
  36 #include <linux/slab.h>
  37 #include <linux/bitmap.h>
  38
  39 #include "mthca_dev.h"
  40
  41 /* Trivial bitmap-based allocator */
  42 u32 mthca_alloc(struct mthca_alloc *alloc)
  43 {
  44         unsigned long flags;
  45         u32 obj;
  46
  47         spin_lock_irqsave(&alloc->lock, flags);
  48
  49         obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
  50         if (obj >= alloc->max) {
  51                 alloc->top = (alloc->top + alloc->max) & alloc->mask;
  52                 obj = find_first_zero_bit(alloc->table, alloc->max);
  53         }
  54
  55         if (obj < alloc->max) {
  56                 set_bit(obj, alloc->table);
  57                 obj |= alloc->top;
  58         } else
  59                 obj = -1;
  60
  61         spin_unlock_irqrestore(&alloc->lock, flags);
  62
  63         return obj;
  64 }
  65
  66 void mthca_free(struct mthca_alloc *alloc, u32 obj)
  67 {
  68         unsigned long flags;
  69
  70         obj &= alloc->max - 1;
  71
  72         spin_lock_irqsave(&alloc->lock, flags);
  73
  74         clear_bit(obj, alloc->table);
  75         alloc->last = min(alloc->last, obj);
  76         alloc->top = (alloc->top + alloc->max) & alloc->mask;
  77
  78         spin_unlock_irqrestore(&alloc->lock, flags);
  79 }
  80
  81 int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask,
  82                      u32 reserved)
  83 {
  84         int i;
  85
  86         /* num must be a power of 2 */
  87         if (num != 1 << (ffs(num) - 1))
  88                 return -EINVAL;
  89
  90         alloc->last = 0;
  91         alloc->top  = 0;
  92         alloc->max  = num;
  93         alloc->mask = mask;
  94         spin_lock_init(&alloc->lock);
  95         alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof (long),
  96                                GFP_KERNEL);
  97         if (!alloc->table)
  98                 return -ENOMEM;
  99
 100         bitmap_zero(alloc->table, num);
 101         for (i = 0; i < reserved; ++i)
 102                 set_bit(i, alloc->table);
 103
 104         return 0;
 105 }
 106
 107 void mthca_alloc_cleanup(struct mthca_alloc *alloc)
 108 {
 109         kfree(alloc->table);
 110 }
 111
 112 /*
 113  * Array of pointers with lazy allocation of leaf pages.  Callers of
 114  * _get, _set and _clear methods must use a lock or otherwise
 115  * serialize access to the array.
 116  */
 117
 118 #define MTHCA_ARRAY_MASK (PAGE_SIZE / sizeof (void *) - 1)
 119
 120 void *mthca_array_get(struct mthca_array *array, int index)
 121 {
 122         int p = (index * sizeof (void *)) >> PAGE_SHIFT;
 123
 124         if (array->page_list[p].page)
 125                 return array->page_list[p].page[index & MTHCA_ARRAY_MASK];
 126         else
 127                 return NULL;
 128 }
 129
 130 int mthca_array_set(struct mthca_array *array, int index, void *value)
 131 {
 132         int p = (index * sizeof (void *)) >> PAGE_SHIFT;
 133
 134         /* Allocate with GFP_ATOMIC because we'll be called with locks held. */
 135         if (!array->page_list[p].page)
 136                 array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);
 137
 138         if (!array->page_list[p].page)
 139                 return -ENOMEM;
 140
 141         array->page_list[p].page[index & MTHCA_ARRAY_MASK] = value;
 142         ++array->page_list[p].used;
 143
 144         return 0;
 145 }
 146
 147 void mthca_array_clear(struct mthca_array *array, int index)
 148 {
 149         int p = (index * sizeof (void *)) >> PAGE_SHIFT;
 150
 151         if (--array->page_list[p].used == 0) {
 152                 free_page((unsigned long) array->page_list[p].page);
 153                 array->page_list[p].page = NULL;
 154         } else
 155                 array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;
 156
 157         if (array->page_list[p].used < 0)
 158                 pr_debug("Array %p index %d page %d with ref count %d < 0\n",
 159                          array, index, p, array->page_list[p].used);
 160 }
 161
 162 int mthca_array_init(struct mthca_array *array, int nent)
 163 {
 164         int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
 165         int i;
 166
 167         array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL);
 168         if (!array->page_list)
 169                 return -ENOMEM;
 170
 171         for (i = 0; i < npage; ++i) {
 172                 array->page_list[i].page = NULL;
 173                 array->page_list[i].used = 0;
 174         }
 175
 176         return 0;
 177 }
 178
 179 void mthca_array_cleanup(struct mthca_array *array, int nent)
 180 {
 181         int i;
 182
 183         for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
 184                 free_page((unsigned long) array->page_list[i].page);
 185
 186         kfree(array->page_list);
 187 }
 188
 189 /*
 190  * Handling for queue buffers -- we allocate a bunch of memory and
 191  * register it in a memory region at HCA virtual address 0.  If the
 192  * requested size is > max_direct, we split the allocation into
 193  * multiple pages, so we don't require too much contiguous memory.
 194  */
 195
 196 int mthca_buf_alloc(struct mthca_dev *dev, int size, int max_direct,
 197                     union mthca_buf *buf, int *is_direct, struct mthca_pd *pd,
 198                     int hca_write, struct mthca_mr *mr)
 199 {
 200         int err = -ENOMEM;
 201         int npages, shift;
 202         u64 *dma_list = NULL;
 203         dma_addr_t t;
 204         int i;
 205
 206         if (size <= max_direct) {
 207                 *is_direct = 1;
 208                 npages     = 1;
 209                 shift      = get_order(size) + PAGE_SHIFT;
 210
 211                 buf->direct.buf = dma_alloc_coherent(&dev->pdev->dev,
 212                                                      size, &t, GFP_KERNEL);
 213                 if (!buf->direct.buf)
 214                         return -ENOMEM;
 215
 216                 pci_unmap_addr_set(&buf->direct, mapping, t);
 217
 218                 memset(buf->direct.buf, 0, size);
 219
 220                 while (t & ((1 << shift) - 1)) {
 221                         --shift;
 222                         npages *= 2;
 223                 }
 224
 225                 dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
 226                 if (!dma_list)
 227                         goto err_free;
 228
 229                 for (i = 0; i < npages; ++i)
 230                         dma_list[i] = t + i * (1 << shift);
 231         } else {
 232                 *is_direct = 0;
 233                 npages     = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 234                 shift      = PAGE_SHIFT;
 235
 236                 dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
 237                 if (!dma_list)
 238                         return -ENOMEM;
 239
 240                 buf->page_list = kmalloc(npages * sizeof *buf->page_list,
 241                                          GFP_KERNEL);
 242                 if (!buf->page_list)
 243                         goto err_out;
 244
 245                 for (i = 0; i < npages; ++i)
 246                         buf->page_list[i].buf = NULL;
 247
 248                 for (i = 0; i < npages; ++i) {
 249                         buf->page_list[i].buf =
 250                                 dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
 251                                                    &t, GFP_KERNEL);
 252                         if (!buf->page_list[i].buf)
 253                                 goto err_free;
 254
 255                         dma_list[i] = t;
 256                         pci_unmap_addr_set(&buf->page_list[i], mapping, t);
 257
 258                         memset(buf->page_list[i].buf, 0, PAGE_SIZE);
 259                 }
 260         }
 261
 262         err = mthca_mr_alloc_phys(dev, pd->pd_num,
 263                                   dma_list, shift, npages,
 264                                   0, size,
 265                                   MTHCA_MPT_FLAG_LOCAL_READ |
 266                                   (hca_write ? MTHCA_MPT_FLAG_LOCAL_WRITE : 0),
 267                                   mr);
 268         if (err)
 269                 goto err_free;
 270
 271         kfree(dma_list);
 272
 273         return 0;
 274
 275 err_free:
 276         mthca_buf_free(dev, size, buf, *is_direct, NULL);
 277
 278 err_out:
 279         kfree(dma_list);
 280
 281         return err;
 282 }
 283
 284 void mthca_buf_free(struct mthca_dev *dev, int size, union mthca_buf *buf,
 285                     int is_direct, struct mthca_mr *mr)
 286 {
 287         int i;
 288
 289         if (mr)
 290                 mthca_free_mr(dev, mr);
 291
 292         if (is_direct)
 293                 dma_free_coherent(&dev->pdev->dev, size, buf->direct.buf,
 294                                   pci_unmap_addr(&buf->direct, mapping));
 295         else {
 296                 for (i = 0; i < (size + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
 297                         dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
 298                                           buf->page_list[i].buf,
 299                                           pci_unmap_addr(&buf->page_list[i],
 300                                                          mapping));
 301                 kfree(buf->page_list);
 302         }
 303 }