sound/core/memalloc.c

   1 /*
   2  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   3  *                   Takashi Iwai <tiwai@suse.de>
   4  *
   5  *  Generic memory allocators
   6  *
   7  *
   8  *   This program is free software; you can redistribute it and/or modify
   9  *   it under the terms of the GNU General Public License as published by
  10  *   the Free Software Foundation; either version 2 of the License, or
  11  *   (at your option) any later version.
  12  *
  13  *   This program is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *   GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with this program; if not, write to the Free Software
  20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  21  *
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/proc_fs.h>
  26 #include <linux/init.h>
  27 #include <linux/pci.h>
  28 #include <linux/slab.h>
  29 #include <linux/mm.h>
  30 #include <linux/seq_file.h>
  31 #include <asm/uaccess.h>
  32 #include <linux/dma-mapping.h>
  33 #include <linux/moduleparam.h>
  34 #include <linux/mutex.h>
  35 #include <sound/memalloc.h>
  36 #ifdef CONFIG_SBUS
  37 #include <asm/sbus.h>
  38 #endif
  39
  40
  41 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>");
  42 MODULE_DESCRIPTION("Memory allocator for ALSA system.");
  43 MODULE_LICENSE("GPL");
  44
  45
  46 /*
  47  */
  48
  49 void *snd_malloc_sgbuf_pages(struct device *device,
  50                              size_t size, struct snd_dma_buffer *dmab,
  51                              size_t *res_size);
  52 int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab);
  53
  54 /*
  55  */
  56
  57 static DEFINE_MUTEX(list_mutex);
  58 static LIST_HEAD(mem_list_head);
  59
  60 /* buffer preservation list */
  61 struct snd_mem_list {
  62         struct snd_dma_buffer buffer;
  63         unsigned int id;
  64         struct list_head list;
  65 };
  66
  67 /* id for pre-allocated buffers */
  68 #define SNDRV_DMA_DEVICE_UNUSED (unsigned int)-1
  69
  70 #ifdef CONFIG_SND_DEBUG
  71 #define __ASTRING__(x) #x
  72 #define snd_assert(expr, args...) do {\
  73         if (!(expr)) {\
  74                 printk(KERN_ERR "snd-malloc: BUG? (%s) (called from %p)\n", __ASTRING__(expr), __builtin_return_address(0));\
  75                 args;\
  76         }\
  77 } while (0)
  78 #else
  79 #define snd_assert(expr, args...) /**/
  80 #endif
  81
  82 /*
  83  *  Hacks
  84  */
  85
  86 #if defined(__i386__)
  87 /*
  88  * A hack to allocate large buffers via dma_alloc_coherent()
  89  *
  90  * since dma_alloc_coherent always tries GFP_DMA when the requested
  91  * pci memory region is below 32bit, it happens quite often that even
  92  * 2 order of pages cannot be allocated.
  93  *
  94  * so in the following, we allocate at first without dma_mask, so that
  95  * allocation will be done without GFP_DMA.  if the area doesn't match
  96  * with the requested region, then realloate with the original dma_mask
  97  * again.
  98  *
  99  * Really, we want to move this type of thing into dma_alloc_coherent()
 100  * so dma_mask doesn't have to be messed with.
 101  */
 102
 103 static void *snd_dma_hack_alloc_coherent(struct device *dev, size_t size,
 104                                          dma_addr_t *dma_handle,
 105                                          gfp_t flags)
 106 {
 107         void *ret;
 108         u64 dma_mask, coherent_dma_mask;
 109
 110         if (dev == NULL || !dev->dma_mask)
 111                 return dma_alloc_coherent(dev, size, dma_handle, flags);
 112         dma_mask = *dev->dma_mask;
 113         coherent_dma_mask = dev->coherent_dma_mask;
 114         *dev->dma_mask = 0xffffffff;    /* do without masking */
 115         dev->coherent_dma_mask = 0xffffffff;    /* do without masking */
 116         ret = dma_alloc_coherent(dev, size, dma_handle, flags);
 117         *dev->dma_mask = dma_mask;      /* restore */
 118         dev->coherent_dma_mask = coherent_dma_mask;     /* restore */
 119         if (ret) {
 120                 /* obtained address is out of range? */
 121                 if (((unsigned long)*dma_handle + size - 1) & ~dma_mask) {
 122                         /* reallocate with the proper mask */
 123                         dma_free_coherent(dev, size, ret, *dma_handle);
 124                         ret = dma_alloc_coherent(dev, size, dma_handle, flags);
 125                 }
 126         } else {
 127                 /* wish to success now with the proper mask... */
 128                 if (dma_mask != 0xffffffffUL) {
 129                         /* allocation with GFP_ATOMIC to avoid the long stall */
 130                         flags &= ~GFP_KERNEL;
 131                         flags |= GFP_ATOMIC;
 132                         ret = dma_alloc_coherent(dev, size, dma_handle, flags);
 133                 }
 134         }
 135         return ret;
 136 }
 137
 138 /* redefine dma_alloc_coherent for some architectures */
 139 #undef dma_alloc_coherent
 140 #define dma_alloc_coherent snd_dma_hack_alloc_coherent
 141
 142 #endif /* arch */
 143
 144 /*
 145  *
 146  *  Generic memory allocators
 147  *
 148  */
 149
 150 static long snd_allocated_pages; /* holding the number of allocated pages */
 151
 152 static inline void inc_snd_pages(int order)
 153 {
 154         snd_allocated_pages += 1 << order;
 155 }
 156
 157 static inline void dec_snd_pages(int order)
 158 {
 159         snd_allocated_pages -= 1 << order;
 160 }
 161
 162 /**
 163  * snd_malloc_pages - allocate pages with the given size
 164  * @size: the size to allocate in bytes
 165  * @gfp_flags: the allocation conditions, GFP_XXX
 166  *
 167  * Allocates the physically contiguous pages with the given size.
 168  *
 169  * Returns the pointer of the buffer, or NULL if no enoguh memory.
 170  */
 171 void *snd_malloc_pages(size_t size, gfp_t gfp_flags)
 172 {
 173         int pg;
 174         void *res;
 175
 176         snd_assert(size > 0, return NULL);
 177         snd_assert(gfp_flags != 0, return NULL);
 178         gfp_flags |= __GFP_COMP;        /* compound page lets parts be mapped */
 179         pg = get_order(size);
 180         if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL)
 181                 inc_snd_pages(pg);
 182         return res;
 183 }
 184
 185 /**
 186  * snd_free_pages - release the pages
 187  * @ptr: the buffer pointer to release
 188  * @size: the allocated buffer size
 189  *
 190  * Releases the buffer allocated via snd_malloc_pages().
 191  */
 192 void snd_free_pages(void *ptr, size_t size)
 193 {
 194         int pg;
 195
 196         if (ptr == NULL)
 197                 return;
 198         pg = get_order(size);
 199         dec_snd_pages(pg);
 200         free_pages((unsigned long) ptr, pg);
 201 }
 202
 203 /*
 204  *
 205  *  Bus-specific memory allocators
 206  *
 207  */
 208
 209 #ifdef CONFIG_HAS_DMA
 210 /* allocate the coherent DMA pages */
 211 static void *snd_malloc_dev_pages(struct device *dev, size_t size, dma_addr_t *dma)
 212 {
 213         int pg;
 214         void *res;
 215         gfp_t gfp_flags;
 216
 217         snd_assert(size > 0, return NULL);
 218         snd_assert(dma != NULL, return NULL);
 219         pg = get_order(size);
 220         gfp_flags = GFP_KERNEL
 221                 | __GFP_COMP    /* compound page lets parts be mapped */
 222                 | __GFP_NORETRY /* don't trigger OOM-killer */
 223                 | __GFP_NOWARN; /* no stack trace print - this call is non-critical */
 224         res = dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
 225         if (res != NULL)
 226                 inc_snd_pages(pg);
 227
 228         return res;
 229 }
 230
 231 /* free the coherent DMA pages */
 232 static void snd_free_dev_pages(struct device *dev, size_t size, void *ptr,
 233                                dma_addr_t dma)
 234 {
 235         int pg;
 236
 237         if (ptr == NULL)
 238                 return;
 239         pg = get_order(size);
 240         dec_snd_pages(pg);
 241         dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
 242 }
 243 #endif /* CONFIG_HAS_DMA */
 244
 245 #ifdef CONFIG_SBUS
 246
 247 static void *snd_malloc_sbus_pages(struct device *dev, size_t size,
 248                                    dma_addr_t *dma_addr)
 249 {
 250         struct sbus_dev *sdev = (struct sbus_dev *)dev;
 251         int pg;
 252         void *res;
 253
 254         snd_assert(size > 0, return NULL);
 255         snd_assert(dma_addr != NULL, return NULL);
 256         pg = get_order(size);
 257         res = sbus_alloc_consistent(sdev, PAGE_SIZE * (1 << pg), dma_addr);
 258         if (res != NULL)
 259                 inc_snd_pages(pg);
 260         return res;
 261 }
 262
 263 static void snd_free_sbus_pages(struct device *dev, size_t size,
 264                                 void *ptr, dma_addr_t dma_addr)
 265 {
 266         struct sbus_dev *sdev = (struct sbus_dev *)dev;
 267         int pg;
 268
 269         if (ptr == NULL)
 270                 return;
 271         pg = get_order(size);
 272         dec_snd_pages(pg);
 273         sbus_free_consistent(sdev, PAGE_SIZE * (1 << pg), ptr, dma_addr);
 274 }
 275
 276 #endif /* CONFIG_SBUS */
 277
 278 /*
 279  *
 280  *  ALSA generic memory management
 281  *
 282  */
 283
 284
 285 /**
 286  * snd_dma_alloc_pages - allocate the buffer area according to the given type
 287  * @type: the DMA buffer type
 288  * @device: the device pointer
 289  * @size: the buffer size to allocate
 290  * @dmab: buffer allocation record to store the allocated data
 291  *
 292  * Calls the memory-allocator function for the corresponding
 293  * buffer type.
 294  *
 295  * Returns zero if the buffer with the given size is allocated successfuly,
 296  * other a negative value at error.
 297  */
 298 int snd_dma_alloc_pages(int type, struct device *device, size_t size,
 299                         struct snd_dma_buffer *dmab)
 300 {
 301         snd_assert(size > 0, return -ENXIO);
 302         snd_assert(dmab != NULL, return -ENXIO);
 303
 304         dmab->dev.type = type;
 305         dmab->dev.dev = device;
 306         dmab->bytes = 0;
 307         switch (type) {
 308         case SNDRV_DMA_TYPE_CONTINUOUS:
 309                 dmab->area = snd_malloc_pages(size, (unsigned long)device);
 310                 dmab->addr = 0;
 311                 break;
 312 #ifdef CONFIG_SBUS
 313         case SNDRV_DMA_TYPE_SBUS:
 314                 dmab->area = snd_malloc_sbus_pages(device, size, &dmab->addr);
 315                 break;
 316 #endif
 317 #ifdef CONFIG_HAS_DMA
 318         case SNDRV_DMA_TYPE_DEV:
 319                 dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
 320                 break;
 321         case SNDRV_DMA_TYPE_DEV_SG:
 322                 snd_malloc_sgbuf_pages(device, size, dmab, NULL);
 323                 break;
 324 #endif
 325         default:
 326                 printk(KERN_ERR "snd-malloc: invalid device type %d\n", type);
 327                 dmab->area = NULL;
 328                 dmab->addr = 0;
 329                 return -ENXIO;
 330         }
 331         if (! dmab->area)
 332                 return -ENOMEM;
 333         dmab->bytes = size;
 334         return 0;
 335 }
 336
 337 /**
 338  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
 339  * @type: the DMA buffer type
 340  * @device: the device pointer
 341  * @size: the buffer size to allocate
 342  * @dmab: buffer allocation record to store the allocated data
 343  *
 344  * Calls the memory-allocator function for the corresponding
 345  * buffer type.  When no space is left, this function reduces the size and
 346  * tries to allocate again.  The size actually allocated is stored in
 347  * res_size argument.
 348  *
 349  * Returns zero if the buffer with the given size is allocated successfuly,
 350  * other a negative value at error.
 351  */
 352 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
 353                                  struct snd_dma_buffer *dmab)
 354 {
 355         int err;
 356
 357         snd_assert(size > 0, return -ENXIO);
 358         snd_assert(dmab != NULL, return -ENXIO);
 359
 360         while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
 361                 if (err != -ENOMEM)
 362                         return err;
 363                 size >>= 1;
 364                 if (size <= PAGE_SIZE)
 365                         return -ENOMEM;
 366         }
 367         if (! dmab->area)
 368                 return -ENOMEM;
 369         return 0;
 370 }
 371
 372
 373 /**
 374  * snd_dma_free_pages - release the allocated buffer
 375  * @dmab: the buffer allocation record to release
 376  *
 377  * Releases the allocated buffer via snd_dma_alloc_pages().
 378  */
 379 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
 380 {
 381         switch (dmab->dev.type) {
 382         case SNDRV_DMA_TYPE_CONTINUOUS:
 383                 snd_free_pages(dmab->area, dmab->bytes);
 384                 break;
 385 #ifdef CONFIG_SBUS
 386         case SNDRV_DMA_TYPE_SBUS:
 387                 snd_free_sbus_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
 388                 break;
 389 #endif
 390 #ifdef CONFIG_HAS_DMA
 391         case SNDRV_DMA_TYPE_DEV:
 392                 snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
 393                 break;
 394         case SNDRV_DMA_TYPE_DEV_SG:
 395                 snd_free_sgbuf_pages(dmab);
 396                 break;
 397 #endif
 398         default:
 399                 printk(KERN_ERR "snd-malloc: invalid device type %d\n", dmab->dev.type);
 400         }
 401 }
 402
 403
 404 /**
 405  * snd_dma_get_reserved - get the reserved buffer for the given device
 406  * @dmab: the buffer allocation record to store
 407  * @id: the buffer id
 408  *
 409  * Looks for the reserved-buffer list and re-uses if the same buffer
 410  * is found in the list.  When the buffer is found, it's removed from the free list.
 411  *
 412  * Returns the size of buffer if the buffer is found, or zero if not found.
 413  */
 414 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
 415 {
 416         struct snd_mem_list *mem;
 417
 418         snd_assert(dmab, return 0);
 419
 420         mutex_lock(&list_mutex);
 421         list_for_each_entry(mem, &mem_list_head, list) {
 422                 if (mem->id == id &&
 423                     (mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
 424                      ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
 425                         struct device *dev = dmab->dev.dev;
 426                         list_del(&mem->list);
 427                         *dmab = mem->buffer;
 428                         if (dmab->dev.dev == NULL)
 429                                 dmab->dev.dev = dev;
 430                         kfree(mem);
 431                         mutex_unlock(&list_mutex);
 432                         return dmab->bytes;
 433                 }
 434         }
 435         mutex_unlock(&list_mutex);
 436         return 0;
 437 }
 438
 439 /**
 440  * snd_dma_reserve_buf - reserve the buffer
 441  * @dmab: the buffer to reserve
 442  * @id: the buffer id
 443  *
 444  * Reserves the given buffer as a reserved buffer.
 445  *
 446  * Returns zero if successful, or a negative code at error.
 447  */
 448 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id)
 449 {
 450         struct snd_mem_list *mem;
 451
 452         snd_assert(dmab, return -EINVAL);
 453         mem = kmalloc(sizeof(*mem), GFP_KERNEL);
 454         if (! mem)
 455                 return -ENOMEM;
 456         mutex_lock(&list_mutex);
 457         mem->buffer = *dmab;
 458         mem->id = id;
 459         list_add_tail(&mem->list, &mem_list_head);
 460         mutex_unlock(&list_mutex);
 461         return 0;
 462 }
 463
 464 /*
 465  * purge all reserved buffers
 466  */
 467 static void free_all_reserved_pages(void)
 468 {
 469         struct list_head *p;
 470         struct snd_mem_list *mem;
 471
 472         mutex_lock(&list_mutex);
 473         while (! list_empty(&mem_list_head)) {
 474                 p = mem_list_head.next;
 475                 mem = list_entry(p, struct snd_mem_list, list);
 476                 list_del(p);
 477                 snd_dma_free_pages(&mem->buffer);
 478                 kfree(mem);
 479         }
 480         mutex_unlock(&list_mutex);
 481 }
 482
 483
 484 #ifdef CONFIG_PROC_FS
 485 /*
 486  * proc file interface
 487  */
 488 #define SND_MEM_PROC_FILE       "driver/snd-page-alloc"
 489 static struct proc_dir_entry *snd_mem_proc;
 490
 491 static int snd_mem_proc_read(struct seq_file *seq, void *offset)
 492 {
 493         long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
 494         struct snd_mem_list *mem;
 495         int devno;
 496         static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG", "SBUS" };
 497
 498         mutex_lock(&list_mutex);
 499         seq_printf(seq, "pages  : %li bytes (%li pages per %likB)\n",
 500                    pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
 501         devno = 0;
 502         list_for_each_entry(mem, &mem_list_head, list) {
 503                 devno++;
 504                 seq_printf(seq, "buffer %d : ID %08x : type %s\n",
 505                            devno, mem->id, types[mem->buffer.dev.type]);
 506                 seq_printf(seq, "  addr = 0x%lx, size = %d bytes\n",
 507                            (unsigned long)mem->buffer.addr,
 508                            (int)mem->buffer.bytes);
 509         }
 510         mutex_unlock(&list_mutex);
 511         return 0;
 512 }
 513
 514 static int snd_mem_proc_open(struct inode *inode, struct file *file)
 515 {
 516         return single_open(file, snd_mem_proc_read, NULL);
 517 }
 518
 519 /* FIXME: for pci only - other bus? */
 520 #ifdef CONFIG_PCI
 521 #define gettoken(bufp) strsep(bufp, " \t\n")
 522
 523 static ssize_t snd_mem_proc_write(struct file *file, const char __user * buffer,
 524                                   size_t count, loff_t * ppos)
 525 {
 526         char buf[128];
 527         char *token, *p;
 528
 529         if (count > sizeof(buf) - 1)
 530                 return -EINVAL;
 531         if (copy_from_user(buf, buffer, count))
 532                 return -EFAULT;
 533         buf[count] = '\0';
 534
 535         p = buf;
 536         token = gettoken(&p);
 537         if (! token || *token == '#')
 538                 return count;
 539         if (strcmp(token, "add") == 0) {
 540                 char *endp;
 541                 int vendor, device, size, buffers;
 542                 long mask;
 543                 int i, alloced;
 544                 struct pci_dev *pci;
 545
 546                 if ((token = gettoken(&p)) == NULL ||
 547                     (vendor = simple_strtol(token, NULL, 0)) <= 0 ||
 548                     (token = gettoken(&p)) == NULL ||
 549                     (device = simple_strtol(token, NULL, 0)) <= 0 ||
 550                     (token = gettoken(&p)) == NULL ||
 551                     (mask = simple_strtol(token, NULL, 0)) < 0 ||
 552                     (token = gettoken(&p)) == NULL ||
 553                     (size = memparse(token, &endp)) < 64*1024 ||
 554                     size > 16*1024*1024 /* too big */ ||
 555                     (token = gettoken(&p)) == NULL ||
 556                     (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
 557                     buffers > 4) {
 558                         printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
 559                         return count;
 560                 }
 561                 vendor &= 0xffff;
 562                 device &= 0xffff;
 563
 564                 alloced = 0;
 565                 pci = NULL;
 566                 while ((pci = pci_get_device(vendor, device, pci)) != NULL) {
 567                         if (mask > 0 && mask < 0xffffffff) {
 568                                 if (pci_set_dma_mask(pci, mask) < 0 ||
 569                                     pci_set_consistent_dma_mask(pci, mask) < 0) {
 570                                         printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
 571                                         return count;
 572                                 }
 573                         }
 574                         for (i = 0; i < buffers; i++) {
 575                                 struct snd_dma_buffer dmab;
 576                                 memset(&dmab, 0, sizeof(dmab));
 577                                 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
 578                                                         size, &dmab) < 0) {
 579                                         printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
 580                                         pci_dev_put(pci);
 581                                         return count;
 582                                 }
 583                                 snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
 584                         }
 585                         alloced++;
 586                 }
 587                 if (! alloced) {
 588                         for (i = 0; i < buffers; i++) {
 589                                 struct snd_dma_buffer dmab;
 590                                 memset(&dmab, 0, sizeof(dmab));
 591                                 /* FIXME: We can allocate only in ZONE_DMA
 592                                  * without a device pointer!
 593                                  */
 594                                 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, NULL,
 595                                                         size, &dmab) < 0) {
 596                                         printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
 597                                         break;
 598                                 }
 599                                 snd_dma_reserve_buf(&dmab, (unsigned int)((vendor << 16) | device));
 600                         }
 601                 }
 602         } else if (strcmp(token, "erase") == 0)
 603                 /* FIXME: need for releasing each buffer chunk? */
 604                 free_all_reserved_pages();
 605         else
 606                 printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
 607         return count;
 608 }
 609 #endif /* CONFIG_PCI */
 610
 611 static const struct file_operations snd_mem_proc_fops = {
 612         .owner          = THIS_MODULE,
 613         .open           = snd_mem_proc_open,
 614         .read           = seq_read,
 615 #ifdef CONFIG_PCI
 616         .write          = snd_mem_proc_write,
 617 #endif
 618         .llseek         = seq_lseek,
 619         .release        = single_release,
 620 };
 621
 622 #endif /* CONFIG_PROC_FS */
 623
 624 /*
 625  * module entry
 626  */
 627
 628 static int __init snd_mem_init(void)
 629 {
 630 #ifdef CONFIG_PROC_FS
 631         snd_mem_proc = create_proc_entry(SND_MEM_PROC_FILE, 0644, NULL);
 632         if (snd_mem_proc)
 633                 snd_mem_proc->proc_fops = &snd_mem_proc_fops;
 634 #endif
 635         return 0;
 636 }
 637
 638 static void __exit snd_mem_exit(void)
 639 {
 640         remove_proc_entry(SND_MEM_PROC_FILE, NULL);
 641         free_all_reserved_pages();
 642         if (snd_allocated_pages > 0)
 643                 printk(KERN_ERR "snd-malloc: Memory leak?  pages not freed = %li\n", snd_allocated_pages);
 644 }
 645
 646
 647 module_init(snd_mem_init)
 648 module_exit(snd_mem_exit)
 649
 650
 651 /*
 652  * exports
 653  */
 654 EXPORT_SYMBOL(snd_dma_alloc_pages);
 655 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
 656 EXPORT_SYMBOL(snd_dma_free_pages);
 657
 658 EXPORT_SYMBOL(snd_dma_get_reserved_buf);
 659 EXPORT_SYMBOL(snd_dma_reserve_buf);
 660
 661 EXPORT_SYMBOL(snd_malloc_pages);
 662 EXPORT_SYMBOL(snd_free_pages);