array.c 1.2 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * generic arrays
  4. */
  5. #include <linux/slab.h>
  6. #include <sound/core.h>
  7. #include <sound/hdaudio.h>
  8. /**
  9. * snd_array_new - get a new element from the given array
  10. * @array: the array object
  11. *
  12. * Get a new element from the given array. If it exceeds the
  13. * pre-allocated array size, re-allocate the array.
  14. *
  15. * Returns NULL if allocation failed.
  16. */
  17. void *snd_array_new(struct snd_array *array)
  18. {
  19. if (snd_BUG_ON(!array->elem_size))
  20. return NULL;
  21. if (array->used >= array->alloced) {
  22. int num = array->alloced + array->alloc_align;
  23. int oldsize = array->alloced * array->elem_size;
  24. int size = (num + 1) * array->elem_size;
  25. void *nlist;
  26. if (snd_BUG_ON(num >= 4096))
  27. return NULL;
  28. nlist = krealloc(array->list, size, GFP_KERNEL);
  29. if (!nlist)
  30. return NULL;
  31. memset(nlist + oldsize, 0, size - oldsize);
  32. array->list = nlist;
  33. array->alloced = num;
  34. }
  35. return snd_array_elem(array, array->used++);
  36. }
  37. EXPORT_SYMBOL_GPL(snd_array_new);
  38. /**
  39. * snd_array_free - free the given array elements
  40. * @array: the array object
  41. */
  42. void snd_array_free(struct snd_array *array)
  43. {
  44. kfree(array->list);
  45. array->used = 0;
  46. array->alloced = 0;
  47. array->list = NULL;
  48. }
  49. EXPORT_SYMBOL_GPL(snd_array_free);