sound/core/memalloc.c

   1 /*
   2  *  Copyright (c) by Jaroslav Kysela <perex@suse.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/config.h>
  25 #include <linux/module.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/init.h>
  28 #include <linux/pci.h>
  29 #include <linux/slab.h>
  30 #include <linux/mm.h>
  31 #include <asm/uaccess.h>
  32 #include <linux/dma-mapping.h>
  33 #include <linux/moduleparam.h>
  34 #include <asm/semaphore.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@suse.cz>");
  42 MODULE_DESCRIPTION("Memory allocator for ALSA system.");
  43 MODULE_LICENSE("GPL");
  44
  45
  46 #ifndef SNDRV_CARDS
  47 #define SNDRV_CARDS     8
  48 #endif
  49
  50 /*
  51  */
  52
  53 void *snd_malloc_sgbuf_pages(struct device *device,
  54                              size_t size, struct snd_dma_buffer *dmab,
  55                              size_t *res_size);
  56 int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab);
  57
  58 /*
  59  */
  60
  61 static DECLARE_MUTEX(list_mutex);
  62 static LIST_HEAD(mem_list_head);
  63
  64 /* buffer preservation list */
  65 struct snd_mem_list {
  66         struct snd_dma_buffer buffer;
  67         unsigned int id;
  68         struct list_head list;
  69 };
  70
  71 /* id for pre-allocated buffers */
  72 #define SNDRV_DMA_DEVICE_UNUSED (unsigned int)-1
  73
  74 #ifdef CONFIG_SND_DEBUG
  75 #define __ASTRING__(x) #x
  76 #define snd_assert(expr, args...) do {\
  77         if (!(expr)) {\
  78                 printk(KERN_ERR "snd-malloc: BUG? (%s) (called from %p)\n", __ASTRING__(expr), __builtin_return_address(0));\
  79                 args;\
  80         }\
  81 } while (0)
  82 #else
  83 #define snd_assert(expr, args...) /**/
  84 #endif
  85
  86 /*
  87  *  Hacks
  88  */
  89
  90 #if defined(__i386__) || defined(__ppc__) || defined(__x86_64__)
  91 /*
  92  * A hack to allocate large buffers via dma_alloc_coherent()
  93  *
  94  * since dma_alloc_coherent always tries GFP_DMA when the requested
  95  * pci memory region is below 32bit, it happens quite often that even
  96  * 2 order of pages cannot be allocated.
  97  *
  98  * so in the following, we allocate at first without dma_mask, so that
  99  * allocation will be done without GFP_DMA.  if the area doesn't match
 100  * with the requested region, then realloate with the original dma_mask
 101  * again.
 102  *
 103  * Really, we want to move this type of thing into dma_alloc_coherent()
 104  * so dma_mask doesn't have to be messed with.
 105  */
 106
 107 static void *snd_dma_hack_alloc_coherent(struct device *dev, size_t size,
 108                                          dma_addr_t *dma_handle, int flags)
 109 {
 110         void *ret;
 111         u64 dma_mask, coherent_dma_mask;
 112
 113         if (dev == NULL || !dev->dma_mask)
 114                 return dma_alloc_coherent(dev, size, dma_handle, flags);
 115         dma_mask = *dev->dma_mask;
 116         coherent_dma_mask = dev->coherent_dma_mask;
 117         *dev->dma_mask = 0xffffffff;    /* do without masking */
 118         dev->coherent_dma_mask = 0xffffffff;    /* do without masking */
 119         ret = dma_alloc_coherent(dev, size, dma_handle, flags);
 120         *dev->dma_mask = dma_mask;      /* restore */
 121         dev->coherent_dma_mask = coherent_dma_mask;     /* restore */
 122         if (ret) {
 123                 /* obtained address is out of range? */
 124                 if (((unsigned long)*dma_handle + size - 1) & ~dma_mask) {
 125                         /* reallocate with the proper mask */
 126                         dma_free_coherent(dev, size, ret, *dma_handle);
 127                         ret = dma_alloc_coherent(dev, size, dma_handle, flags);
 128                 }
 129         } else {
 130                 /* wish to success now with the proper mask... */
 131                 if (dma_mask != 0xffffffffUL) {
 132                         /* allocation with GFP_ATOMIC to avoid the long stall */
 133                         flags &= ~GFP_KERNEL;
 134                         flags |= GFP_ATOMIC;
 135                         ret = dma_alloc_coherent(dev, size, dma_handle, flags);
 136                 }
 137         }
 138         return ret;
 139 }
 140
 141 /* redefine dma_alloc_coherent for some architectures */
 142 #undef dma_alloc_coherent
 143 #define dma_alloc_coherent snd_dma_hack_alloc_coherent
 144
 145 #endif /* arch */
 146
 147 #if ! defined(__arm__)
 148 #define NEED_RESERVE_PAGES
 149 #endif
 150
 151 /*
 152  *
 153  *  Generic memory allocators
 154  *
 155  */
 156
 157 static long snd_allocated_pages; /* holding the number of allocated pages */
 158
 159 static inline void inc_snd_pages(int order)
 160 {
 161         snd_allocated_pages += 1 << order;
 162 }
 163
 164 static inline void dec_snd_pages(int order)
 165 {
 166         snd_allocated_pages -= 1 << order;
 167 }
 168
 169 static void mark_pages(struct page *page, int order)
 170 {
 171         struct page *last_page = page + (1 << order);
 172         while (page < last_page)
 173                 SetPageReserved(page++);
 174 }
 175
 176 static void unmark_pages(struct page *page, int order)
 177 {
 178         struct page *last_page = page + (1 << order);
 179         while (page < last_page)
 180                 ClearPageReserved(page++);
 181 }
 182
 183 /**
 184  * snd_malloc_pages - allocate pages with the given size
 185  * @size: the size to allocate in bytes
 186  * @gfp_flags: the allocation conditions, GFP_XXX
 187  *
 188  * Allocates the physically contiguous pages with the given size.
 189  *
 190  * Returns the pointer of the buffer, or NULL if no enoguh memory.
 191  */
 192 void *snd_malloc_pages(size_t size, unsigned int gfp_flags)
 193 {
 194         int pg;
 195         void *res;
 196
 197         snd_assert(size > 0, return NULL);
 198         snd_assert(gfp_flags != 0, return NULL);
 199         pg = get_order(size);
 200         if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL) {
 201                 mark_pages(virt_to_page(res), pg);
 202                 inc_snd_pages(pg);
 203         }
 204         return res;
 205 }
 206
 207 /**
 208  * snd_free_pages - release the pages
 209  * @ptr: the buffer pointer to release
 210  * @size: the allocated buffer size
 211  *
 212  * Releases the buffer allocated via snd_malloc_pages().
 213  */
 214 void snd_free_pages(void *ptr, size_t size)
 215 {
 216         int pg;
 217
 218         if (ptr == NULL)
 219                 return;
 220         pg = get_order(size);
 221         dec_snd_pages(pg);
 222         unmark_pages(virt_to_page(ptr), pg);
 223         free_pages((unsigned long) ptr, pg);
 224 }
 225
 226 /*
 227  *
 228  *  Bus-specific memory allocators
 229  *
 230  */
 231
 232 /* allocate the coherent DMA pages */
 233 static void *snd_malloc_dev_pages(struct device *dev, size_t size, dma_addr_t *dma)
 234 {
 235         int pg;
 236         void *res;
 237         unsigned int gfp_flags;
 238
 239         snd_assert(size > 0, return NULL);
 240         snd_assert(dma != NULL, return NULL);
 241         pg = get_order(size);
 242         gfp_flags = GFP_KERNEL
 243                 | __GFP_NORETRY /* don't trigger OOM-killer */
 244                 | __GFP_NOWARN; /* no stack trace print - this call is non-critical */
 245         res = dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
 246         if (res != NULL) {
 247 #ifdef NEED_RESERVE_PAGES
 248                 mark_pages(virt_to_page(res), pg); /* should be dma_to_page() */
 249 #endif
 250                 inc_snd_pages(pg);
 251         }
 252
 253         return res;
 254 }
 255
 256 /* free the coherent DMA pages */
 257 static void snd_free_dev_pages(struct device *dev, size_t size, void *ptr,
 258                                dma_addr_t dma)
 259 {
 260         int pg;
 261
 262         if (ptr == NULL)
 263                 return;
 264         pg = get_order(size);
 265         dec_snd_pages(pg);
 266 #ifdef NEED_RESERVE_PAGES
 267         unmark_pages(virt_to_page(ptr), pg); /* should be dma_to_page() */
 268 #endif
 269         dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
 270 }
 271
 272 #ifdef CONFIG_SBUS
 273
 274 static void *snd_malloc_sbus_pages(struct device *dev, size_t size,
 275                                    dma_addr_t *dma_addr)
 276 {
 277         struct sbus_dev *sdev = (struct sbus_dev *)dev;
 278         int pg;
 279         void *res;
 280
 281         snd_assert(size > 0, return NULL);
 282         snd_assert(dma_addr != NULL, return NULL);
 283         pg = get_order(size);
 284         res = sbus_alloc_consistent(sdev, PAGE_SIZE * (1 << pg), dma_addr);
 285         if (res != NULL)
 286                 inc_snd_pages(pg);
 287         return res;
 288 }
 289
 290 static void snd_free_sbus_pages(struct device *dev, size_t size,
 291                                 void *ptr, dma_addr_t dma_addr)
 292 {
 293         struct sbus_dev *sdev = (struct sbus_dev *)dev;
 294         int pg;
 295
 296         if (ptr == NULL)
 297                 return;
 298         pg = get_order(size);
 299         dec_snd_pages(pg);
 300         sbus_free_consistent(sdev, PAGE_SIZE * (1 << pg), ptr, dma_addr);
 301 }
 302
 303 #endif /* CONFIG_SBUS */
 304
 305 /*
 306  *
 307  *  ALSA generic memory management
 308  *
 309  */
 310
 311
 312 /**
 313  * snd_dma_alloc_pages - allocate the buffer area according to the given type
 314  * @type: the DMA buffer type
 315  * @device: the device pointer
 316  * @size: the buffer size to allocate
 317  * @dmab: buffer allocation record to store the allocated data
 318  *
 319  * Calls the memory-allocator function for the corresponding
 320  * buffer type.
 321  *
 322  * Returns zero if the buffer with the given size is allocated successfuly,
 323  * other a negative value at error.
 324  */
 325 int snd_dma_alloc_pages(int type, struct device *device, size_t size,
 326                         struct snd_dma_buffer *dmab)
 327 {
 328         snd_assert(size > 0, return -ENXIO);
 329         snd_assert(dmab != NULL, return -ENXIO);
 330
 331         dmab->dev.type = type;
 332         dmab->dev.dev = device;
 333         dmab->bytes = 0;
 334         switch (type) {
 335         case SNDRV_DMA_TYPE_CONTINUOUS:
 336                 dmab->area = snd_malloc_pages(size, (unsigned long)device);
 337                 dmab->addr = 0;
 338                 break;
 339 #ifdef CONFIG_SBUS
 340         case SNDRV_DMA_TYPE_SBUS:
 341                 dmab->area = snd_malloc_sbus_pages(device, size, &dmab->addr);
 342                 break;
 343 #endif
 344         case SNDRV_DMA_TYPE_DEV:
 345                 dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
 346                 break;
 347         case SNDRV_DMA_TYPE_DEV_SG:
 348                 snd_malloc_sgbuf_pages(device, size, dmab, NULL);
 349                 break;
 350         default:
 351                 printk(KERN_ERR "snd-malloc: invalid device type %d\n", type);
 352                 dmab->area = NULL;
 353                 dmab->addr = 0;
 354                 return -ENXIO;
 355         }
 356         if (! dmab->area)
 357                 return -ENOMEM;
 358         dmab->bytes = size;
 359         return 0;
 360 }
 361
 362 /**
 363  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
 364  * @type: the DMA buffer type
 365  * @device: the device pointer
 366  * @size: the buffer size to allocate
 367  * @dmab: buffer allocation record to store the allocated data
 368  *
 369  * Calls the memory-allocator function for the corresponding
 370  * buffer type.  When no space is left, this function reduces the size and
 371  * tries to allocate again.  The size actually allocated is stored in
 372  * res_size argument.
 373  *
 374  * Returns zero if the buffer with the given size is allocated successfuly,
 375  * other a negative value at error.
 376  */
 377 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
 378                                  struct snd_dma_buffer *dmab)
 379 {
 380         int err;
 381
 382         snd_assert(size > 0, return -ENXIO);
 383         snd_assert(dmab != NULL, return -ENXIO);
 384
 385         while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
 386                 if (err != -ENOMEM)
 387                         return err;
 388                 size >>= 1;
 389                 if (size <= PAGE_SIZE)
 390                         return -ENOMEM;
 391         }
 392         if (! dmab->area)
 393                 return -ENOMEM;
 394         return 0;
 395 }
 396
 397
 398 /**
 399  * snd_dma_free_pages - release the allocated buffer
 400  * @dmab: the buffer allocation record to release
 401  *
 402  * Releases the allocated buffer via snd_dma_alloc_pages().
 403  */
 404 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
 405 {
 406         switch (dmab->dev.type) {
 407         case SNDRV_DMA_TYPE_CONTINUOUS:
 408                 snd_free_pages(dmab->area, dmab->bytes);
 409                 break;
 410 #ifdef CONFIG_SBUS
 411         case SNDRV_DMA_TYPE_SBUS:
 412                 snd_free_sbus_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
 413                 break;
 414 #endif
 415         case SNDRV_DMA_TYPE_DEV:
 416                 snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
 417                 break;
 418         case SNDRV_DMA_TYPE_DEV_SG:
 419                 snd_free_sgbuf_pages(dmab);
 420                 break;
 421         default:
 422                 printk(KERN_ERR "snd-malloc: invalid device type %d\n", dmab->dev.type);
 423         }
 424 }
 425
 426
 427 /**
 428  * snd_dma_get_reserved - get the reserved buffer for the given device
 429  * @dmab: the buffer allocation record to store
 430  * @id: the buffer id
 431  *
 432  * Looks for the reserved-buffer list and re-uses if the same buffer
 433  * is found in the list.  When the buffer is found, it's removed from the free list.
 434  *
 435  * Returns the size of buffer if the buffer is found, or zero if not found.
 436  */
 437 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
 438 {
 439         struct list_head *p;
 440         struct snd_mem_list *mem;
 441
 442         snd_assert(dmab, return 0);
 443
 444         down(&list_mutex);
 445         list_for_each(p, &mem_list_head) {
 446                 mem = list_entry(p, struct snd_mem_list, list);
 447                 if (mem->id == id &&
 448                     (mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
 449                      ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
 450                         struct device *dev = dmab->dev.dev;
 451                         list_del(p);
 452                         *dmab = mem->buffer;
 453                         if (dmab->dev.dev == NULL)
 454                                 dmab->dev.dev = dev;
 455                         kfree(mem);
 456                         up(&list_mutex);
 457                         return dmab->bytes;
 458                 }
 459         }
 460         up(&list_mutex);
 461         return 0;
 462 }
 463
 464 /**
 465  * snd_dma_reserve_buf - reserve the buffer
 466  * @dmab: the buffer to reserve
 467  * @id: the buffer id
 468  *
 469  * Reserves the given buffer as a reserved buffer.
 470  *
 471  * Returns zero if successful, or a negative code at error.
 472  */
 473 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id)
 474 {
 475         struct snd_mem_list *mem;
 476
 477         snd_assert(dmab, return -EINVAL);
 478         mem = kmalloc(sizeof(*mem), GFP_KERNEL);
 479         if (! mem)
 480                 return -ENOMEM;
 481         down(&list_mutex);
 482         mem->buffer = *dmab;
 483         mem->id = id;
 484         list_add_tail(&mem->list, &mem_list_head);
 485         up(&list_mutex);
 486         return 0;
 487 }
 488
 489 /*
 490  * purge all reserved buffers
 491  */
 492 static void free_all_reserved_pages(void)
 493 {
 494         struct list_head *p;
 495         struct snd_mem_list *mem;
 496
 497         down(&list_mutex);
 498         while (! list_empty(&mem_list_head)) {
 499                 p = mem_list_head.next;
 500                 mem = list_entry(p, struct snd_mem_list, list);
 501                 list_del(p);
 502                 snd_dma_free_pages(&mem->buffer);
 503                 kfree(mem);
 504         }
 505         up(&list_mutex);
 506 }
 507
 508
 509 #ifdef CONFIG_PROC_FS
 510 /*
 511  * proc file interface
 512  */
 513 #define SND_MEM_PROC_FILE       "driver/snd-page-alloc"
 514 struct proc_dir_entry *snd_mem_proc;
 515
 516 static int snd_mem_proc_read(char *page, char **start, off_t off,
 517                              int count, int *eof, void *data)
 518 {
 519         int len = 0;
 520         long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
 521         struct list_head *p;
 522         struct snd_mem_list *mem;
 523         int devno;
 524         static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG", "SBUS" };
 525
 526         down(&list_mutex);
 527         len += snprintf(page + len, count - len,
 528                         "pages  : %li bytes (%li pages per %likB)\n",
 529                         pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
 530         devno = 0;
 531         list_for_each(p, &mem_list_head) {
 532                 mem = list_entry(p, struct snd_mem_list, list);
 533                 devno++;
 534                 len += snprintf(page + len, count - len,
 535                                 "buffer %d : ID %08x : type %s\n",
 536                                 devno, mem->id, types[mem->buffer.dev.type]);
 537                 len += snprintf(page + len, count - len,
 538                                 "  addr = 0x%lx, size = %d bytes\n",
 539                                 (unsigned long)mem->buffer.addr, (int)mem->buffer.bytes);
 540         }
 541         up(&list_mutex);
 542         return len;
 543 }
 544
 545 /* FIXME: for pci only - other bus? */
 546 #ifdef CONFIG_PCI
 547 #define gettoken(bufp) strsep(bufp, " \t\n")
 548
 549 static int snd_mem_proc_write(struct file *file, const char __user *buffer,
 550                               unsigned long count, void *data)
 551 {
 552         char buf[128];
 553         char *token, *p;
 554
 555         if (count > ARRAY_SIZE(buf) - 1)
 556                 count = ARRAY_SIZE(buf) - 1;
 557         if (copy_from_user(buf, buffer, count))
 558                 return -EFAULT;
 559         buf[ARRAY_SIZE(buf) - 1] = '\0';
 560
 561         p = buf;
 562         token = gettoken(&p);
 563         if (! token || *token == '#')
 564                 return (int)count;
 565         if (strcmp(token, "add") == 0) {
 566                 char *endp;
 567                 int vendor, device, size, buffers;
 568                 long mask;
 569                 int i, alloced;
 570                 struct pci_dev *pci;
 571
 572                 if ((token = gettoken(&p)) == NULL ||
 573                     (vendor = simple_strtol(token, NULL, 0)) <= 0 ||
 574                     (token = gettoken(&p)) == NULL ||
 575                     (device = simple_strtol(token, NULL, 0)) <= 0 ||
 576                     (token = gettoken(&p)) == NULL ||
 577                     (mask = simple_strtol(token, NULL, 0)) < 0 ||
 578                     (token = gettoken(&p)) == NULL ||
 579                     (size = memparse(token, &endp)) < 64*1024 ||
 580                     size > 16*1024*1024 /* too big */ ||
 581                     (token = gettoken(&p)) == NULL ||
 582                     (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
 583                     buffers > 4) {
 584                         printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
 585                         return (int)count;
 586                 }
 587                 vendor &= 0xffff;
 588                 device &= 0xffff;
 589
 590                 alloced = 0;
 591                 pci = NULL;
 592                 while ((pci = pci_find_device(vendor, device, pci)) != NULL) {
 593                         if (mask > 0 && mask < 0xffffffff) {
 594                                 if (pci_set_dma_mask(pci, mask) < 0 ||
 595                                     pci_set_consistent_dma_mask(pci, mask) < 0) {
 596                                         printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
 597                                         return (int)count;
 598                                 }
 599                         }
 600                         for (i = 0; i < buffers; i++) {
 601                                 struct snd_dma_buffer dmab;
 602                                 memset(&dmab, 0, sizeof(dmab));
 603                                 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
 604                                                         size, &dmab) < 0) {
 605                                         printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
 606                                         return (int)count;
 607                                 }
 608                                 snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
 609                         }
 610                         alloced++;
 611                 }
 612                 if (! alloced) {
 613                         for (i = 0; i < buffers; i++) {
 614                                 struct snd_dma_buffer dmab;
 615                                 memset(&dmab, 0, sizeof(dmab));
 616                                 /* FIXME: We can allocate only in ZONE_DMA
 617                                  * without a device pointer!
 618                                  */
 619                                 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, NULL,
 620                                                         size, &dmab) < 0) {
 621                                         printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
 622                                         break;
 623                                 }
 624                                 snd_dma_reserve_buf(&dmab, (unsigned int)((vendor << 16) | device));
 625                         }
 626                 }
 627         } else if (strcmp(token, "erase") == 0)
 628                 /* FIXME: need for releasing each buffer chunk? */
 629                 free_all_reserved_pages();
 630         else
 631                 printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
 632         return (int)count;
 633 }
 634 #endif /* CONFIG_PCI */
 635 #endif /* CONFIG_PROC_FS */
 636
 637 /*
 638  * module entry
 639  */
 640
 641 static int __init snd_mem_init(void)
 642 {
 643 #ifdef CONFIG_PROC_FS
 644         snd_mem_proc = create_proc_entry(SND_MEM_PROC_FILE, 0644, NULL);
 645         if (snd_mem_proc) {
 646                 snd_mem_proc->read_proc = snd_mem_proc_read;
 647 #ifdef CONFIG_PCI
 648                 snd_mem_proc->write_proc = snd_mem_proc_write;
 649 #endif
 650         }
 651 #endif
 652         return 0;
 653 }
 654
 655 static void __exit snd_mem_exit(void)
 656 {
 657         if (snd_mem_proc)
 658                 remove_proc_entry(SND_MEM_PROC_FILE, NULL);
 659         free_all_reserved_pages();
 660         if (snd_allocated_pages > 0)
 661                 printk(KERN_ERR "snd-malloc: Memory leak?  pages not freed = %li\n", snd_allocated_pages);
 662 }
 663
 664
 665 module_init(snd_mem_init)
 666 module_exit(snd_mem_exit)
 667
 668
 669 /*
 670  * exports
 671  */
 672 EXPORT_SYMBOL(snd_dma_alloc_pages);
 673 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
 674 EXPORT_SYMBOL(snd_dma_free_pages);
 675
 676 EXPORT_SYMBOL(snd_dma_get_reserved_buf);
 677 EXPORT_SYMBOL(snd_dma_reserve_buf);
 678
 679 EXPORT_SYMBOL(snd_malloc_pages);
 680 EXPORT_SYMBOL(snd_free_pages);