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 <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@suse.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__) || defined(__ppc__) || defined(__x86_64__)
  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 #if ! defined(__arm__)
 145 #define NEED_RESERVE_PAGES
 146 #endif
 147
 148 /*
 149  *
 150  *  Generic memory allocators
 151  *
 152  */
 153
 154 static long snd_allocated_pages; /* holding the number of allocated pages */
 155
 156 static inline void inc_snd_pages(int order)
 157 {
 158         snd_allocated_pages += 1 << order;
 159 }
 160
 161 static inline void dec_snd_pages(int order)
 162 {
 163         snd_allocated_pages -= 1 << order;
 164 }
 165
 166 static void mark_pages(struct page *page, int order)
 167 {
 168         struct page *last_page = page + (1 << order);
 169         while (page < last_page)
 170                 SetPageReserved(page++);
 171 }
 172
 173 static void unmark_pages(struct page *page, int order)
 174 {
 175         struct page *last_page = page + (1 << order);
 176         while (page < last_page)
 177                 ClearPageReserved(page++);
 178 }
 179
 180 /**
 181  * snd_malloc_pages - allocate pages with the given size
 182  * @size: the size to allocate in bytes
 183  * @gfp_flags: the allocation conditions, GFP_XXX
 184  *
 185  * Allocates the physically contiguous pages with the given size.
 186  *
 187  * Returns the pointer of the buffer, or NULL if no enoguh memory.
 188  */
 189 void *snd_malloc_pages(size_t size, gfp_t gfp_flags)
 190 {
 191         int pg;
 192         void *res;
 193
 194         snd_assert(size > 0, return NULL);
 195         snd_assert(gfp_flags != 0, return NULL);
 196         gfp_flags |= __GFP_COMP;        /* compound page lets parts be mapped */
 197         pg = get_order(size);
 198         if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL) {
 199                 mark_pages(virt_to_page(res), pg);
 200                 inc_snd_pages(pg);
 201         }
 202         return res;
 203 }
 204
 205 /**
 206  * snd_free_pages - release the pages
 207  * @ptr: the buffer pointer to release
 208  * @size: the allocated buffer size
 209  *
 210  * Releases the buffer allocated via snd_malloc_pages().
 211  */
 212 void snd_free_pages(void *ptr, size_t size)
 213 {
 214         int pg;
 215
 216         if (ptr == NULL)
 217                 return;
 218         pg = get_order(size);
 219         dec_snd_pages(pg);
 220         unmark_pages(virt_to_page(ptr), pg);
 221         free_pages((unsigned long) ptr, pg);
 222 }
 223
 224 /*
 225  *
 226  *  Bus-specific memory allocators
 227  *
 228  */
 229
 230 /* allocate the coherent DMA pages */
 231 static void *snd_malloc_dev_pages(struct device *dev, size_t size, dma_addr_t *dma)
 232 {
 233         int pg;
 234         void *res;
 235         gfp_t gfp_flags;
 236
 237         snd_assert(size > 0, return NULL);
 238         snd_assert(dma != NULL, return NULL);
 239         pg = get_order(size);
 240         gfp_flags = GFP_KERNEL
 241                 | __GFP_COMP    /* compound page lets parts be mapped */
 242                 | __GFP_NORETRY /* don't trigger OOM-killer */
 243                 | __GFP_NOWARN; /* no stack trace print - this call is non-critical */
 244         res = dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
 245         if (res != NULL) {
 246 #ifdef NEED_RESERVE_PAGES
 247                 mark_pages(virt_to_page(res), pg); /* should be dma_to_page() */
 248 #endif
 249                 inc_snd_pages(pg);
 250         }
 251
 252         return res;
 253 }
 254
 255 /* free the coherent DMA pages */
 256 static void snd_free_dev_pages(struct device *dev, size_t size, void *ptr,
 257                                dma_addr_t dma)
 258 {
 259         int pg;
 260
 261         if (ptr == NULL)
 262                 return;
 263         pg = get_order(size);
 264         dec_snd_pages(pg);
 265 #ifdef NEED_RESERVE_PAGES
 266         unmark_pages(virt_to_page(ptr), pg); /* should be dma_to_page() */
 267 #endif
 268         dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
 269 }
 270
 271 #ifdef CONFIG_SBUS
 272
 273 static void *snd_malloc_sbus_pages(struct device *dev, size_t size,
 274                                    dma_addr_t *dma_addr)
 275 {
 276         struct sbus_dev *sdev = (struct sbus_dev *)dev;
 277         int pg;
 278         void *res;
 279
 280         snd_assert(size > 0, return NULL);
 281         snd_assert(dma_addr != NULL, return NULL);
 282         pg = get_order(size);
 283         res = sbus_alloc_consistent(sdev, PAGE_SIZE * (1 << pg), dma_addr);
 284         if (res != NULL)
 285                 inc_snd_pages(pg);
 286         return res;
 287 }
 288
 289 static void snd_free_sbus_pages(struct device *dev, size_t size,
 290                                 void *ptr, dma_addr_t dma_addr)
 291 {
 292         struct sbus_dev *sdev = (struct sbus_dev *)dev;
 293         int pg;
 294
 295         if (ptr == NULL)
 296                 return;
 297         pg = get_order(size);
 298         dec_snd_pages(pg);
 299         sbus_free_consistent(sdev, PAGE_SIZE * (1 << pg), ptr, dma_addr);
 300 }
 301
 302 #endif /* CONFIG_SBUS */
 303
 304 /*
 305  *
 306  *  ALSA generic memory management
 307  *
 308  */
 309
 310
 311 /**
 312  * snd_dma_alloc_pages - allocate the buffer area according to the given type
 313  * @type: the DMA buffer type
 314  * @device: the device pointer
 315  * @size: the buffer size to allocate
 316  * @dmab: buffer allocation record to store the allocated data
 317  *
 318  * Calls the memory-allocator function for the corresponding
 319  * buffer type.
 320  *
 321  * Returns zero if the buffer with the given size is allocated successfuly,
 322  * other a negative value at error.
 323  */
 324 int snd_dma_alloc_pages(int type, struct device *device, size_t size,
 325                         struct snd_dma_buffer *dmab)
 326 {
 327         snd_assert(size > 0, return -ENXIO);
 328         snd_assert(dmab != NULL, return -ENXIO);
 329
 330         dmab->dev.type = type;
 331         dmab->dev.dev = device;
 332         dmab->bytes = 0;
 333         switch (type) {
 334         case SNDRV_DMA_TYPE_CONTINUOUS:
 335                 dmab->area = snd_malloc_pages(size, (unsigned long)device);
 336                 dmab->addr = 0;
 337                 break;
 338 #ifdef CONFIG_SBUS
 339         case SNDRV_DMA_TYPE_SBUS:
 340                 dmab->area = snd_malloc_sbus_pages(device, size, &dmab->addr);
 341                 break;
 342 #endif
 343         case SNDRV_DMA_TYPE_DEV:
 344                 dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
 345                 break;
 346         case SNDRV_DMA_TYPE_DEV_SG:
 347                 snd_malloc_sgbuf_pages(device, size, dmab, NULL);
 348                 break;
 349         default:
 350                 printk(KERN_ERR "snd-malloc: invalid device type %d\n", type);
 351                 dmab->area = NULL;
 352                 dmab->addr = 0;
 353                 return -ENXIO;
 354         }
 355         if (! dmab->area)
 356                 return -ENOMEM;
 357         dmab->bytes = size;
 358         return 0;
 359 }
 360
 361 /**
 362  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
 363  * @type: the DMA buffer type
 364  * @device: the device pointer
 365  * @size: the buffer size to allocate
 366  * @dmab: buffer allocation record to store the allocated data
 367  *
 368  * Calls the memory-allocator function for the corresponding
 369  * buffer type.  When no space is left, this function reduces the size and
 370  * tries to allocate again.  The size actually allocated is stored in
 371  * res_size argument.
 372  *
 373  * Returns zero if the buffer with the given size is allocated successfuly,
 374  * other a negative value at error.
 375  */
 376 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
 377                                  struct snd_dma_buffer *dmab)
 378 {
 379         int err;
 380
 381         snd_assert(size > 0, return -ENXIO);
 382         snd_assert(dmab != NULL, return -ENXIO);
 383
 384         while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
 385                 if (err != -ENOMEM)
 386                         return err;
 387                 size >>= 1;
 388                 if (size <= PAGE_SIZE)
 389                         return -ENOMEM;
 390         }
 391         if (! dmab->area)
 392                 return -ENOMEM;
 393         return 0;
 394 }
 395
 396
 397 /**
 398  * snd_dma_free_pages - release the allocated buffer
 399  * @dmab: the buffer allocation record to release
 400  *
 401  * Releases the allocated buffer via snd_dma_alloc_pages().
 402  */
 403 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
 404 {
 405         switch (dmab->dev.type) {
 406         case SNDRV_DMA_TYPE_CONTINUOUS:
 407                 snd_free_pages(dmab->area, dmab->bytes);
 408                 break;
 409 #ifdef CONFIG_SBUS
 410         case SNDRV_DMA_TYPE_SBUS:
 411                 snd_free_sbus_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
 412                 break;
 413 #endif
 414         case SNDRV_DMA_TYPE_DEV:
 415                 snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
 416                 break;
 417         case SNDRV_DMA_TYPE_DEV_SG:
 418                 snd_free_sgbuf_pages(dmab);
 419                 break;
 420         default:
 421                 printk(KERN_ERR "snd-malloc: invalid device type %d\n", dmab->dev.type);
 422         }
 423 }
 424
 425
 426 /**
 427  * snd_dma_get_reserved - get the reserved buffer for the given device
 428  * @dmab: the buffer allocation record to store
 429  * @id: the buffer id
 430  *
 431  * Looks for the reserved-buffer list and re-uses if the same buffer
 432  * is found in the list.  When the buffer is found, it's removed from the free list.
 433  *
 434  * Returns the size of buffer if the buffer is found, or zero if not found.
 435  */
 436 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
 437 {
 438         struct list_head *p;
 439         struct snd_mem_list *mem;
 440
 441         snd_assert(dmab, return 0);
 442
 443         mutex_lock(&list_mutex);
 444         list_for_each(p, &mem_list_head) {
 445                 mem = list_entry(p, struct snd_mem_list, list);
 446                 if (mem->id == id &&
 447                     (mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
 448                      ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
 449                         struct device *dev = dmab->dev.dev;
 450                         list_del(p);
 451                         *dmab = mem->buffer;
 452                         if (dmab->dev.dev == NULL)
 453                                 dmab->dev.dev = dev;
 454                         kfree(mem);
 455                         mutex_unlock(&list_mutex);
 456                         return dmab->bytes;
 457                 }
 458         }
 459         mutex_unlock(&list_mutex);
 460         return 0;
 461 }
 462
 463 /**
 464  * snd_dma_reserve_buf - reserve the buffer
 465  * @dmab: the buffer to reserve
 466  * @id: the buffer id
 467  *
 468  * Reserves the given buffer as a reserved buffer.
 469  *
 470  * Returns zero if successful, or a negative code at error.
 471  */
 472 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id)
 473 {
 474         struct snd_mem_list *mem;
 475
 476         snd_assert(dmab, return -EINVAL);
 477         mem = kmalloc(sizeof(*mem), GFP_KERNEL);
 478         if (! mem)
 479                 return -ENOMEM;
 480         mutex_lock(&list_mutex);
 481         mem->buffer = *dmab;
 482         mem->id = id;
 483         list_add_tail(&mem->list, &mem_list_head);
 484         mutex_unlock(&list_mutex);
 485         return 0;
 486 }
 487
 488 /*
 489  * purge all reserved buffers
 490  */
 491 static void free_all_reserved_pages(void)
 492 {
 493         struct list_head *p;
 494         struct snd_mem_list *mem;
 495
 496         mutex_lock(&list_mutex);
 497         while (! list_empty(&mem_list_head)) {
 498                 p = mem_list_head.next;
 499                 mem = list_entry(p, struct snd_mem_list, list);
 500                 list_del(p);
 501                 snd_dma_free_pages(&mem->buffer);
 502                 kfree(mem);
 503         }
 504         mutex_unlock(&list_mutex);
 505 }
 506
 507
 508 #ifdef CONFIG_PROC_FS
 509 /*
 510  * proc file interface
 511  */
 512 #define SND_MEM_PROC_FILE       "driver/snd-page-alloc"
 513 static struct proc_dir_entry *snd_mem_proc;
 514
 515 static int snd_mem_proc_read(char *page, char **start, off_t off,
 516                              int count, int *eof, void *data)
 517 {
 518         int len = 0;
 519         long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
 520         struct list_head *p;
 521         struct snd_mem_list *mem;
 522         int devno;
 523         static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG", "SBUS" };
 524
 525         mutex_lock(&list_mutex);
 526         len += snprintf(page + len, count - len,
 527                         "pages  : %li bytes (%li pages per %likB)\n",
 528                         pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
 529         devno = 0;
 530         list_for_each(p, &mem_list_head) {
 531                 mem = list_entry(p, struct snd_mem_list, list);
 532                 devno++;
 533                 len += snprintf(page + len, count - len,
 534                                 "buffer %d : ID %08x : type %s\n",
 535                                 devno, mem->id, types[mem->buffer.dev.type]);
 536                 len += snprintf(page + len, count - len,
 537                                 "  addr = 0x%lx, size = %d bytes\n",
 538                                 (unsigned long)mem->buffer.addr, (int)mem->buffer.bytes);
 539         }
 540         mutex_unlock(&list_mutex);
 541         return len;
 542 }
 543
 544 /* FIXME: for pci only - other bus? */
 545 #ifdef CONFIG_PCI
 546 #define gettoken(bufp) strsep(bufp, " \t\n")
 547
 548 static int snd_mem_proc_write(struct file *file, const char __user *buffer,
 549                               unsigned long count, void *data)
 550 {
 551         char buf[128];
 552         char *token, *p;
 553
 554         if (count > ARRAY_SIZE(buf) - 1)
 555                 count = ARRAY_SIZE(buf) - 1;
 556         if (copy_from_user(buf, buffer, count))
 557                 return -EFAULT;
 558         buf[ARRAY_SIZE(buf) - 1] = '\0';
 559
 560         p = buf;
 561         token = gettoken(&p);
 562         if (! token || *token == '#')
 563                 return (int)count;
 564         if (strcmp(token, "add") == 0) {
 565                 char *endp;
 566                 int vendor, device, size, buffers;
 567                 long mask;
 568                 int i, alloced;
 569                 struct pci_dev *pci;
 570
 571                 if ((token = gettoken(&p)) == NULL ||
 572                     (vendor = simple_strtol(token, NULL, 0)) <= 0 ||
 573                     (token = gettoken(&p)) == NULL ||
 574                     (device = simple_strtol(token, NULL, 0)) <= 0 ||
 575                     (token = gettoken(&p)) == NULL ||
 576                     (mask = simple_strtol(token, NULL, 0)) < 0 ||
 577                     (token = gettoken(&p)) == NULL ||
 578                     (size = memparse(token, &endp)) < 64*1024 ||
 579                     size > 16*1024*1024 /* too big */ ||
 580                     (token = gettoken(&p)) == NULL ||
 581                     (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
 582                     buffers > 4) {
 583                         printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
 584                         return (int)count;
 585                 }
 586                 vendor &= 0xffff;
 587                 device &= 0xffff;
 588
 589                 alloced = 0;
 590                 pci = NULL;
 591                 while ((pci = pci_get_device(vendor, device, pci)) != NULL) {
 592                         if (mask > 0 && mask < 0xffffffff) {
 593                                 if (pci_set_dma_mask(pci, mask) < 0 ||
 594                                     pci_set_consistent_dma_mask(pci, mask) < 0) {
 595                                         printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
 596                                         return (int)count;
 597                                 }
 598                         }
 599                         for (i = 0; i < buffers; i++) {
 600                                 struct snd_dma_buffer dmab;
 601                                 memset(&dmab, 0, sizeof(dmab));
 602                                 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
 603                                                         size, &dmab) < 0) {
 604                                         printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
 605                                         pci_dev_put(pci);
 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         remove_proc_entry(SND_MEM_PROC_FILE, NULL);
 658         free_all_reserved_pages();
 659         if (snd_allocated_pages > 0)
 660                 printk(KERN_ERR "snd-malloc: Memory leak?  pages not freed = %li\n", snd_allocated_pages);
 661 }
 662
 663
 664 module_init(snd_mem_init)
 665 module_exit(snd_mem_exit)
 666
 667
 668 /*
 669  * exports
 670  */
 671 EXPORT_SYMBOL(snd_dma_alloc_pages);
 672 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
 673 EXPORT_SYMBOL(snd_dma_free_pages);
 674
 675 EXPORT_SYMBOL(snd_dma_get_reserved_buf);
 676 EXPORT_SYMBOL(snd_dma_reserve_buf);
 677
 678 EXPORT_SYMBOL(snd_malloc_pages);
 679 EXPORT_SYMBOL(snd_free_pages);