linux/sound/core/memalloc.c
Pierre-Louis Bossart b1c1412450 ALSA: core: memalloc: fix fallthrough position
Fix cppcheck, the fallthrough only makes sense within the conditional
block

sound/core/memalloc.c:161:3: style:inconclusive: Statements following
return, break, continue, goto or throw will never be
executed. [unreachableCode]
  fallthrough;
  ^

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200902212133.30964-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-09-03 09:24:49 +02:00

256 lines
6.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
* Takashi Iwai <tiwai@suse.de>
*
* Generic memory allocators
*/
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <linux/genalloc.h>
#include <linux/vmalloc.h>
#ifdef CONFIG_X86
#include <asm/set_memory.h>
#endif
#include <sound/memalloc.h>
/*
*
* Bus-specific memory allocators
*
*/
#ifdef CONFIG_HAS_DMA
/* allocate the coherent DMA pages */
static void snd_malloc_dev_pages(struct snd_dma_buffer *dmab, size_t size)
{
gfp_t gfp_flags;
gfp_flags = GFP_KERNEL
| __GFP_COMP /* compound page lets parts be mapped */
| __GFP_NORETRY /* don't trigger OOM-killer */
| __GFP_NOWARN; /* no stack trace print - this call is non-critical */
dmab->area = dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr,
gfp_flags);
#ifdef CONFIG_X86
if (dmab->area && dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)
set_memory_wc((unsigned long)dmab->area,
PAGE_ALIGN(size) >> PAGE_SHIFT);
#endif
}
/* free the coherent DMA pages */
static void snd_free_dev_pages(struct snd_dma_buffer *dmab)
{
#ifdef CONFIG_X86
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)
set_memory_wb((unsigned long)dmab->area,
PAGE_ALIGN(dmab->bytes) >> PAGE_SHIFT);
#endif
dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
}
#ifdef CONFIG_GENERIC_ALLOCATOR
/**
* snd_malloc_dev_iram - allocate memory from on-chip internal ram
* @dmab: buffer allocation record to store the allocated data
* @size: number of bytes to allocate from the iram
*
* This function requires iram phandle provided via of_node
*/
static void snd_malloc_dev_iram(struct snd_dma_buffer *dmab, size_t size)
{
struct device *dev = dmab->dev.dev;
struct gen_pool *pool = NULL;
dmab->area = NULL;
dmab->addr = 0;
if (dev->of_node)
pool = of_gen_pool_get(dev->of_node, "iram", 0);
if (!pool)
return;
/* Assign the pool into private_data field */
dmab->private_data = pool;
dmab->area = gen_pool_dma_alloc(pool, size, &dmab->addr);
}
/**
* snd_free_dev_iram - free allocated specific memory from on-chip internal ram
* @dmab: buffer allocation record to store the allocated data
*/
static void snd_free_dev_iram(struct snd_dma_buffer *dmab)
{
struct gen_pool *pool = dmab->private_data;
if (pool && dmab->area)
gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);
}
#endif /* CONFIG_GENERIC_ALLOCATOR */
#endif /* CONFIG_HAS_DMA */
/*
*
* ALSA generic memory management
*
*/
static inline gfp_t snd_mem_get_gfp_flags(const struct device *dev,
gfp_t default_gfp)
{
if (!dev)
return default_gfp;
else
return (__force gfp_t)(unsigned long)dev;
}
/**
* snd_dma_alloc_pages - allocate the buffer area according to the given type
* @type: the DMA buffer type
* @device: the device pointer
* @size: the buffer size to allocate
* @dmab: buffer allocation record to store the allocated data
*
* Calls the memory-allocator function for the corresponding
* buffer type.
*
* Return: Zero if the buffer with the given size is allocated successfully,
* otherwise a negative value on error.
*/
int snd_dma_alloc_pages(int type, struct device *device, size_t size,
struct snd_dma_buffer *dmab)
{
gfp_t gfp;
if (WARN_ON(!size))
return -ENXIO;
if (WARN_ON(!dmab))
return -ENXIO;
dmab->dev.type = type;
dmab->dev.dev = device;
dmab->bytes = 0;
dmab->area = NULL;
dmab->addr = 0;
dmab->private_data = NULL;
switch (type) {
case SNDRV_DMA_TYPE_CONTINUOUS:
gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL);
dmab->area = alloc_pages_exact(size, gfp);
break;
case SNDRV_DMA_TYPE_VMALLOC:
gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL | __GFP_HIGHMEM);
dmab->area = __vmalloc(size, gfp);
break;
#ifdef CONFIG_HAS_DMA
#ifdef CONFIG_GENERIC_ALLOCATOR
case SNDRV_DMA_TYPE_DEV_IRAM:
snd_malloc_dev_iram(dmab, size);
if (dmab->area)
break;
/* Internal memory might have limited size and no enough space,
* so if we fail to malloc, try to fetch memory traditionally.
*/
dmab->dev.type = SNDRV_DMA_TYPE_DEV;
fallthrough;
#endif /* CONFIG_GENERIC_ALLOCATOR */
case SNDRV_DMA_TYPE_DEV:
case SNDRV_DMA_TYPE_DEV_UC:
snd_malloc_dev_pages(dmab, size);
break;
#endif
#ifdef CONFIG_SND_DMA_SGBUF
case SNDRV_DMA_TYPE_DEV_SG:
case SNDRV_DMA_TYPE_DEV_UC_SG:
snd_malloc_sgbuf_pages(device, size, dmab, NULL);
break;
#endif
default:
pr_err("snd-malloc: invalid device type %d\n", type);
return -ENXIO;
}
if (! dmab->area)
return -ENOMEM;
dmab->bytes = size;
return 0;
}
EXPORT_SYMBOL(snd_dma_alloc_pages);
/**
* snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
* @type: the DMA buffer type
* @device: the device pointer
* @size: the buffer size to allocate
* @dmab: buffer allocation record to store the allocated data
*
* Calls the memory-allocator function for the corresponding
* buffer type. When no space is left, this function reduces the size and
* tries to allocate again. The size actually allocated is stored in
* res_size argument.
*
* Return: Zero if the buffer with the given size is allocated successfully,
* otherwise a negative value on error.
*/
int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
struct snd_dma_buffer *dmab)
{
int err;
while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
if (err != -ENOMEM)
return err;
if (size <= PAGE_SIZE)
return -ENOMEM;
size >>= 1;
size = PAGE_SIZE << get_order(size);
}
if (! dmab->area)
return -ENOMEM;
return 0;
}
EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
/**
* snd_dma_free_pages - release the allocated buffer
* @dmab: the buffer allocation record to release
*
* Releases the allocated buffer via snd_dma_alloc_pages().
*/
void snd_dma_free_pages(struct snd_dma_buffer *dmab)
{
switch (dmab->dev.type) {
case SNDRV_DMA_TYPE_CONTINUOUS:
free_pages_exact(dmab->area, dmab->bytes);
break;
case SNDRV_DMA_TYPE_VMALLOC:
vfree(dmab->area);
break;
#ifdef CONFIG_HAS_DMA
#ifdef CONFIG_GENERIC_ALLOCATOR
case SNDRV_DMA_TYPE_DEV_IRAM:
snd_free_dev_iram(dmab);
break;
#endif /* CONFIG_GENERIC_ALLOCATOR */
case SNDRV_DMA_TYPE_DEV:
case SNDRV_DMA_TYPE_DEV_UC:
snd_free_dev_pages(dmab);
break;
#endif
#ifdef CONFIG_SND_DMA_SGBUF
case SNDRV_DMA_TYPE_DEV_SG:
case SNDRV_DMA_TYPE_DEV_UC_SG:
snd_free_sgbuf_pages(dmab);
break;
#endif
default:
pr_err("snd-malloc: invalid device type %d\n", dmab->dev.type);
}
}
EXPORT_SYMBOL(snd_dma_free_pages);