sound/hda/array.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * generic arrays
   4  */
   5
   6 #include <linux/slab.h>
   7 #include <sound/core.h>
   8 #include <sound/hdaudio.h>
   9
  10 /**
  11  * snd_array_new - get a new element from the given array
  12  * @array: the array object
  13  *
  14  * Get a new element from the given array.  If it exceeds the
  15  * pre-allocated array size, re-allocate the array.
  16  *
  17  * Returns NULL if allocation failed.
  18  */
  19 void *snd_array_new(struct snd_array *array)
  20 {
  21         if (snd_BUG_ON(!array->elem_size))
  22                 return NULL;
  23         if (array->used >= array->alloced) {
  24                 int num = array->alloced + array->alloc_align;
  25                 int oldsize = array->alloced * array->elem_size;
  26                 int size = (num + 1) * array->elem_size;
  27                 void *nlist;
  28                 if (snd_BUG_ON(num >= 4096))
  29                         return NULL;
  30                 nlist = krealloc(array->list, size, GFP_KERNEL);
  31                 if (!nlist)
  32                         return NULL;
  33                 memset(nlist + oldsize, 0, size - oldsize);
  34                 array->list = nlist;
  35                 array->alloced = num;
  36         }
  37         return snd_array_elem(array, array->used++);
  38 }
  39 EXPORT_SYMBOL_GPL(snd_array_new);
  40
  41 /**
  42  * snd_array_free - free the given array elements
  43  * @array: the array object
  44  */
  45 void snd_array_free(struct snd_array *array)
  46 {
  47         kfree(array->list);
  48         array->used = 0;
  49         array->alloced = 0;
  50         array->list = NULL;
  51 }
  52 EXPORT_SYMBOL_GPL(snd_array_free);