alistair23-linux/sound/hda/array.c
Takashi Iwai 33baefe5e7 ALSA: hda: Fix krealloc() with __GFP_ZERO usage
krealloc() doesn't work always properly with __GFP_ZERO flag as
expected.  For clearing the reallocated area, we need to clear
explicitly instead.

Reported-by: Joe Perches <joe@perches.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-08-03 15:17:22 +02:00

52 lines
1.2 KiB
C

/*
* generic arrays
*/
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/hdaudio.h>
/**
* snd_array_new - get a new element from the given array
* @array: the array object
*
* Get a new element from the given array. If it exceeds the
* pre-allocated array size, re-allocate the array.
*
* Returns NULL if allocation failed.
*/
void *snd_array_new(struct snd_array *array)
{
if (snd_BUG_ON(!array->elem_size))
return NULL;
if (array->used >= array->alloced) {
int num = array->alloced + array->alloc_align;
int oldsize = array->alloced * array->elem_size;
int size = (num + 1) * array->elem_size;
void *nlist;
if (snd_BUG_ON(num >= 4096))
return NULL;
nlist = krealloc(array->list, size, GFP_KERNEL);
if (!nlist)
return NULL;
memset(nlist + oldsize, 0, size - oldsize);
array->list = nlist;
array->alloced = num;
}
return snd_array_elem(array, array->used++);
}
EXPORT_SYMBOL_GPL(snd_array_new);
/**
* snd_array_free - free the given array elements
* @array: the array object
*/
void snd_array_free(struct snd_array *array)
{
kfree(array->list);
array->used = 0;
array->alloced = 0;
array->list = NULL;
}
EXPORT_SYMBOL_GPL(snd_array_free);