linux/sound/core/memalloc.c
Takashi Iwai 53466ebdec ALSA: memalloc: Workaround for Xen PV
We change recently the memalloc helper to use
dma_alloc_noncontiguous() and the fallback to get_pages().  Although
lots of issues with IOMMU (or non-IOMMU) have been addressed, but
there seems still a regression on Xen PV.  Interestingly, the only
proper way to work is use dma_alloc_coherent().  The use of
dma_alloc_coherent() for SG buffer was dropped as it's problematic on
IOMMU systems.  OTOH, Xen PV has a different way, and it's fine to use
the dma_alloc_coherent().

This patch is a workaround for Xen PV.  It consists of the following
changes:
- For Xen PV, use only the fallback allocation without
  dma_alloc_noncontiguous()
- In the fallback allocation, use dma_alloc_coherent();
  the DMA address from dma_alloc_coherent() is returned in get_addr
  ops
- The DMA addresses are stored in an array; the first entry stores the
  number of allocated pages in lower bits, which are referred at
  releasing pages again

Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Fixes: a8d302a0b7 ("ALSA: memalloc: Revive x86-specific WC page allocations again")
Fixes: 9736a32513 ("ALSA: memalloc: Don't fall back for SG-buffer with IOMMU")
Link: https://lore.kernel.org/r/87tu256lqs.wl-tiwai@suse.de
Link: https://lore.kernel.org/r/20230125153104.5527-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-01-27 09:16:24 +01:00

951 lines
25 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/dma-map-ops.h>
#include <linux/genalloc.h>
#include <linux/highmem.h>
#include <linux/vmalloc.h>
#ifdef CONFIG_X86
#include <asm/set_memory.h>
#endif
#include <sound/memalloc.h>
#include "memalloc_local.h"
#define DEFAULT_GFP \
(GFP_KERNEL | \
__GFP_RETRY_MAYFAIL | /* don't trigger OOM-killer */ \
__GFP_NOWARN) /* no stack trace print - this call is non-critical */
static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab);
#ifdef CONFIG_SND_DMA_SGBUF
static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size);
#endif
static void *__snd_dma_alloc_pages(struct snd_dma_buffer *dmab, size_t size)
{
const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
if (WARN_ON_ONCE(!ops || !ops->alloc))
return NULL;
return ops->alloc(dmab, size);
}
/**
* snd_dma_alloc_dir_pages - allocate the buffer area according to the given
* type and direction
* @type: the DMA buffer type
* @device: the device pointer
* @dir: DMA direction
* @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_dir_pages(int type, struct device *device,
enum dma_data_direction dir, size_t size,
struct snd_dma_buffer *dmab)
{
if (WARN_ON(!size))
return -ENXIO;
if (WARN_ON(!dmab))
return -ENXIO;
size = PAGE_ALIGN(size);
dmab->dev.type = type;
dmab->dev.dev = device;
dmab->dev.dir = dir;
dmab->bytes = 0;
dmab->addr = 0;
dmab->private_data = NULL;
dmab->area = __snd_dma_alloc_pages(dmab, size);
if (!dmab->area)
return -ENOMEM;
dmab->bytes = size;
return 0;
}
EXPORT_SYMBOL(snd_dma_alloc_dir_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)
{
const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
if (ops && ops->free)
ops->free(dmab);
}
EXPORT_SYMBOL(snd_dma_free_pages);
/* called by devres */
static void __snd_release_pages(struct device *dev, void *res)
{
snd_dma_free_pages(res);
}
/**
* snd_devm_alloc_dir_pages - allocate the buffer and manage with devres
* @dev: the device pointer
* @type: the DMA buffer type
* @dir: DMA direction
* @size: the buffer size to allocate
*
* Allocate buffer pages depending on the given type and manage using devres.
* The pages will be released automatically at the device removal.
*
* Unlike snd_dma_alloc_pages(), this function requires the real device pointer,
* hence it can't work with SNDRV_DMA_TYPE_CONTINUOUS or
* SNDRV_DMA_TYPE_VMALLOC type.
*
* Return: the snd_dma_buffer object at success, or NULL if failed
*/
struct snd_dma_buffer *
snd_devm_alloc_dir_pages(struct device *dev, int type,
enum dma_data_direction dir, size_t size)
{
struct snd_dma_buffer *dmab;
int err;
if (WARN_ON(type == SNDRV_DMA_TYPE_CONTINUOUS ||
type == SNDRV_DMA_TYPE_VMALLOC))
return NULL;
dmab = devres_alloc(__snd_release_pages, sizeof(*dmab), GFP_KERNEL);
if (!dmab)
return NULL;
err = snd_dma_alloc_dir_pages(type, dev, dir, size, dmab);
if (err < 0) {
devres_free(dmab);
return NULL;
}
devres_add(dev, dmab);
return dmab;
}
EXPORT_SYMBOL_GPL(snd_devm_alloc_dir_pages);
/**
* snd_dma_buffer_mmap - perform mmap of the given DMA buffer
* @dmab: buffer allocation information
* @area: VM area information
*
* Return: zero if successful, or a negative error code
*/
int snd_dma_buffer_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
const struct snd_malloc_ops *ops;
if (!dmab)
return -ENOENT;
ops = snd_dma_get_ops(dmab);
if (ops && ops->mmap)
return ops->mmap(dmab, area);
else
return -ENOENT;
}
EXPORT_SYMBOL(snd_dma_buffer_mmap);
#ifdef CONFIG_HAS_DMA
/**
* snd_dma_buffer_sync - sync DMA buffer between CPU and device
* @dmab: buffer allocation information
* @mode: sync mode
*/
void snd_dma_buffer_sync(struct snd_dma_buffer *dmab,
enum snd_dma_sync_mode mode)
{
const struct snd_malloc_ops *ops;
if (!dmab || !dmab->dev.need_sync)
return;
ops = snd_dma_get_ops(dmab);
if (ops && ops->sync)
ops->sync(dmab, mode);
}
EXPORT_SYMBOL_GPL(snd_dma_buffer_sync);
#endif /* CONFIG_HAS_DMA */
/**
* snd_sgbuf_get_addr - return the physical address at the corresponding offset
* @dmab: buffer allocation information
* @offset: offset in the ring buffer
*
* Return: the physical address
*/
dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab, size_t offset)
{
const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
if (ops && ops->get_addr)
return ops->get_addr(dmab, offset);
else
return dmab->addr + offset;
}
EXPORT_SYMBOL(snd_sgbuf_get_addr);
/**
* snd_sgbuf_get_page - return the physical page at the corresponding offset
* @dmab: buffer allocation information
* @offset: offset in the ring buffer
*
* Return: the page pointer
*/
struct page *snd_sgbuf_get_page(struct snd_dma_buffer *dmab, size_t offset)
{
const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
if (ops && ops->get_page)
return ops->get_page(dmab, offset);
else
return virt_to_page(dmab->area + offset);
}
EXPORT_SYMBOL(snd_sgbuf_get_page);
/**
* snd_sgbuf_get_chunk_size - compute the max chunk size with continuous pages
* on sg-buffer
* @dmab: buffer allocation information
* @ofs: offset in the ring buffer
* @size: the requested size
*
* Return: the chunk size
*/
unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
unsigned int ofs, unsigned int size)
{
const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
if (ops && ops->get_chunk_size)
return ops->get_chunk_size(dmab, ofs, size);
else
return size;
}
EXPORT_SYMBOL(snd_sgbuf_get_chunk_size);
/*
* Continuous pages allocator
*/
static void *do_alloc_pages(struct device *dev, size_t size, dma_addr_t *addr,
bool wc)
{
void *p;
gfp_t gfp = GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN;
again:
p = alloc_pages_exact(size, gfp);
if (!p)
return NULL;
*addr = page_to_phys(virt_to_page(p));
if (!dev)
return p;
if ((*addr + size - 1) & ~dev->coherent_dma_mask) {
if (IS_ENABLED(CONFIG_ZONE_DMA32) && !(gfp & GFP_DMA32)) {
gfp |= GFP_DMA32;
goto again;
}
if (IS_ENABLED(CONFIG_ZONE_DMA) && !(gfp & GFP_DMA)) {
gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
goto again;
}
}
#ifdef CONFIG_X86
if (wc)
set_memory_wc((unsigned long)(p), size >> PAGE_SHIFT);
#endif
return p;
}
static void do_free_pages(void *p, size_t size, bool wc)
{
#ifdef CONFIG_X86
if (wc)
set_memory_wb((unsigned long)(p), size >> PAGE_SHIFT);
#endif
free_pages_exact(p, size);
}
static void *snd_dma_continuous_alloc(struct snd_dma_buffer *dmab, size_t size)
{
return do_alloc_pages(dmab->dev.dev, size, &dmab->addr, false);
}
static void snd_dma_continuous_free(struct snd_dma_buffer *dmab)
{
do_free_pages(dmab->area, dmab->bytes, false);
}
static int snd_dma_continuous_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
return remap_pfn_range(area, area->vm_start,
dmab->addr >> PAGE_SHIFT,
area->vm_end - area->vm_start,
area->vm_page_prot);
}
static const struct snd_malloc_ops snd_dma_continuous_ops = {
.alloc = snd_dma_continuous_alloc,
.free = snd_dma_continuous_free,
.mmap = snd_dma_continuous_mmap,
};
/*
* VMALLOC allocator
*/
static void *snd_dma_vmalloc_alloc(struct snd_dma_buffer *dmab, size_t size)
{
return vmalloc(size);
}
static void snd_dma_vmalloc_free(struct snd_dma_buffer *dmab)
{
vfree(dmab->area);
}
static int snd_dma_vmalloc_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
return remap_vmalloc_range(area, dmab->area, 0);
}
#define get_vmalloc_page_addr(dmab, offset) \
page_to_phys(vmalloc_to_page((dmab)->area + (offset)))
static dma_addr_t snd_dma_vmalloc_get_addr(struct snd_dma_buffer *dmab,
size_t offset)
{
return get_vmalloc_page_addr(dmab, offset) + offset % PAGE_SIZE;
}
static struct page *snd_dma_vmalloc_get_page(struct snd_dma_buffer *dmab,
size_t offset)
{
return vmalloc_to_page(dmab->area + offset);
}
static unsigned int
snd_dma_vmalloc_get_chunk_size(struct snd_dma_buffer *dmab,
unsigned int ofs, unsigned int size)
{
unsigned int start, end;
unsigned long addr;
start = ALIGN_DOWN(ofs, PAGE_SIZE);
end = ofs + size - 1; /* the last byte address */
/* check page continuity */
addr = get_vmalloc_page_addr(dmab, start);
for (;;) {
start += PAGE_SIZE;
if (start > end)
break;
addr += PAGE_SIZE;
if (get_vmalloc_page_addr(dmab, start) != addr)
return start - ofs;
}
/* ok, all on continuous pages */
return size;
}
static const struct snd_malloc_ops snd_dma_vmalloc_ops = {
.alloc = snd_dma_vmalloc_alloc,
.free = snd_dma_vmalloc_free,
.mmap = snd_dma_vmalloc_mmap,
.get_addr = snd_dma_vmalloc_get_addr,
.get_page = snd_dma_vmalloc_get_page,
.get_chunk_size = snd_dma_vmalloc_get_chunk_size,
};
#ifdef CONFIG_HAS_DMA
/*
* IRAM allocator
*/
#ifdef CONFIG_GENERIC_ALLOCATOR
static void *snd_dma_iram_alloc(struct snd_dma_buffer *dmab, size_t size)
{
struct device *dev = dmab->dev.dev;
struct gen_pool *pool;
void *p;
if (dev->of_node) {
pool = of_gen_pool_get(dev->of_node, "iram", 0);
/* Assign the pool into private_data field */
dmab->private_data = pool;
p = gen_pool_dma_alloc_align(pool, size, &dmab->addr, PAGE_SIZE);
if (p)
return p;
}
/* 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;
return __snd_dma_alloc_pages(dmab, size);
}
static void snd_dma_iram_free(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);
}
static int snd_dma_iram_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
return remap_pfn_range(area, area->vm_start,
dmab->addr >> PAGE_SHIFT,
area->vm_end - area->vm_start,
area->vm_page_prot);
}
static const struct snd_malloc_ops snd_dma_iram_ops = {
.alloc = snd_dma_iram_alloc,
.free = snd_dma_iram_free,
.mmap = snd_dma_iram_mmap,
};
#endif /* CONFIG_GENERIC_ALLOCATOR */
/*
* Coherent device pages allocator
*/
static void *snd_dma_dev_alloc(struct snd_dma_buffer *dmab, size_t size)
{
return dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP);
}
static void snd_dma_dev_free(struct snd_dma_buffer *dmab)
{
dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
}
static int snd_dma_dev_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
return dma_mmap_coherent(dmab->dev.dev, area,
dmab->area, dmab->addr, dmab->bytes);
}
static const struct snd_malloc_ops snd_dma_dev_ops = {
.alloc = snd_dma_dev_alloc,
.free = snd_dma_dev_free,
.mmap = snd_dma_dev_mmap,
};
/*
* Write-combined pages
*/
/* x86-specific allocations */
#ifdef CONFIG_SND_DMA_SGBUF
static void *snd_dma_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
{
return do_alloc_pages(dmab->dev.dev, size, &dmab->addr, true);
}
static void snd_dma_wc_free(struct snd_dma_buffer *dmab)
{
do_free_pages(dmab->area, dmab->bytes, true);
}
static int snd_dma_wc_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
return snd_dma_continuous_mmap(dmab, area);
}
#else
static void *snd_dma_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
{
return dma_alloc_wc(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP);
}
static void snd_dma_wc_free(struct snd_dma_buffer *dmab)
{
dma_free_wc(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
}
static int snd_dma_wc_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
return dma_mmap_wc(dmab->dev.dev, area,
dmab->area, dmab->addr, dmab->bytes);
}
#endif /* CONFIG_SND_DMA_SGBUF */
static const struct snd_malloc_ops snd_dma_wc_ops = {
.alloc = snd_dma_wc_alloc,
.free = snd_dma_wc_free,
.mmap = snd_dma_wc_mmap,
};
/*
* Non-contiguous pages allocator
*/
static void *snd_dma_noncontig_alloc(struct snd_dma_buffer *dmab, size_t size)
{
struct sg_table *sgt;
void *p;
#ifdef CONFIG_SND_DMA_SGBUF
if (cpu_feature_enabled(X86_FEATURE_XENPV))
return snd_dma_sg_fallback_alloc(dmab, size);
#endif
sgt = dma_alloc_noncontiguous(dmab->dev.dev, size, dmab->dev.dir,
DEFAULT_GFP, 0);
#ifdef CONFIG_SND_DMA_SGBUF
if (!sgt && !get_dma_ops(dmab->dev.dev))
return snd_dma_sg_fallback_alloc(dmab, size);
#endif
if (!sgt)
return NULL;
dmab->dev.need_sync = dma_need_sync(dmab->dev.dev,
sg_dma_address(sgt->sgl));
p = dma_vmap_noncontiguous(dmab->dev.dev, size, sgt);
if (p) {
dmab->private_data = sgt;
/* store the first page address for convenience */
dmab->addr = snd_sgbuf_get_addr(dmab, 0);
} else {
dma_free_noncontiguous(dmab->dev.dev, size, sgt, dmab->dev.dir);
}
return p;
}
static void snd_dma_noncontig_free(struct snd_dma_buffer *dmab)
{
dma_vunmap_noncontiguous(dmab->dev.dev, dmab->area);
dma_free_noncontiguous(dmab->dev.dev, dmab->bytes, dmab->private_data,
dmab->dev.dir);
}
static int snd_dma_noncontig_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
return dma_mmap_noncontiguous(dmab->dev.dev, area,
dmab->bytes, dmab->private_data);
}
static void snd_dma_noncontig_sync(struct snd_dma_buffer *dmab,
enum snd_dma_sync_mode mode)
{
if (mode == SNDRV_DMA_SYNC_CPU) {
if (dmab->dev.dir == DMA_TO_DEVICE)
return;
invalidate_kernel_vmap_range(dmab->area, dmab->bytes);
dma_sync_sgtable_for_cpu(dmab->dev.dev, dmab->private_data,
dmab->dev.dir);
} else {
if (dmab->dev.dir == DMA_FROM_DEVICE)
return;
flush_kernel_vmap_range(dmab->area, dmab->bytes);
dma_sync_sgtable_for_device(dmab->dev.dev, dmab->private_data,
dmab->dev.dir);
}
}
static inline void snd_dma_noncontig_iter_set(struct snd_dma_buffer *dmab,
struct sg_page_iter *piter,
size_t offset)
{
struct sg_table *sgt = dmab->private_data;
__sg_page_iter_start(piter, sgt->sgl, sgt->orig_nents,
offset >> PAGE_SHIFT);
}
static dma_addr_t snd_dma_noncontig_get_addr(struct snd_dma_buffer *dmab,
size_t offset)
{
struct sg_dma_page_iter iter;
snd_dma_noncontig_iter_set(dmab, &iter.base, offset);
__sg_page_iter_dma_next(&iter);
return sg_page_iter_dma_address(&iter) + offset % PAGE_SIZE;
}
static struct page *snd_dma_noncontig_get_page(struct snd_dma_buffer *dmab,
size_t offset)
{
struct sg_page_iter iter;
snd_dma_noncontig_iter_set(dmab, &iter, offset);
__sg_page_iter_next(&iter);
return sg_page_iter_page(&iter);
}
static unsigned int
snd_dma_noncontig_get_chunk_size(struct snd_dma_buffer *dmab,
unsigned int ofs, unsigned int size)
{
struct sg_dma_page_iter iter;
unsigned int start, end;
unsigned long addr;
start = ALIGN_DOWN(ofs, PAGE_SIZE);
end = ofs + size - 1; /* the last byte address */
snd_dma_noncontig_iter_set(dmab, &iter.base, start);
if (!__sg_page_iter_dma_next(&iter))
return 0;
/* check page continuity */
addr = sg_page_iter_dma_address(&iter);
for (;;) {
start += PAGE_SIZE;
if (start > end)
break;
addr += PAGE_SIZE;
if (!__sg_page_iter_dma_next(&iter) ||
sg_page_iter_dma_address(&iter) != addr)
return start - ofs;
}
/* ok, all on continuous pages */
return size;
}
static const struct snd_malloc_ops snd_dma_noncontig_ops = {
.alloc = snd_dma_noncontig_alloc,
.free = snd_dma_noncontig_free,
.mmap = snd_dma_noncontig_mmap,
.sync = snd_dma_noncontig_sync,
.get_addr = snd_dma_noncontig_get_addr,
.get_page = snd_dma_noncontig_get_page,
.get_chunk_size = snd_dma_noncontig_get_chunk_size,
};
/* x86-specific SG-buffer with WC pages */
#ifdef CONFIG_SND_DMA_SGBUF
#define sg_wc_address(it) ((unsigned long)page_address(sg_page_iter_page(it)))
static void *snd_dma_sg_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
{
void *p = snd_dma_noncontig_alloc(dmab, size);
struct sg_table *sgt = dmab->private_data;
struct sg_page_iter iter;
if (!p)
return NULL;
if (dmab->dev.type != SNDRV_DMA_TYPE_DEV_WC_SG)
return p;
for_each_sgtable_page(sgt, &iter, 0)
set_memory_wc(sg_wc_address(&iter), 1);
return p;
}
static void snd_dma_sg_wc_free(struct snd_dma_buffer *dmab)
{
struct sg_table *sgt = dmab->private_data;
struct sg_page_iter iter;
for_each_sgtable_page(sgt, &iter, 0)
set_memory_wb(sg_wc_address(&iter), 1);
snd_dma_noncontig_free(dmab);
}
static int snd_dma_sg_wc_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
return dma_mmap_noncontiguous(dmab->dev.dev, area,
dmab->bytes, dmab->private_data);
}
static const struct snd_malloc_ops snd_dma_sg_wc_ops = {
.alloc = snd_dma_sg_wc_alloc,
.free = snd_dma_sg_wc_free,
.mmap = snd_dma_sg_wc_mmap,
.sync = snd_dma_noncontig_sync,
.get_addr = snd_dma_noncontig_get_addr,
.get_page = snd_dma_noncontig_get_page,
.get_chunk_size = snd_dma_noncontig_get_chunk_size,
};
/* Fallback SG-buffer allocations for x86 */
struct snd_dma_sg_fallback {
bool use_dma_alloc_coherent;
size_t count;
struct page **pages;
/* DMA address array; the first page contains #pages in ~PAGE_MASK */
dma_addr_t *addrs;
};
static void __snd_dma_sg_fallback_free(struct snd_dma_buffer *dmab,
struct snd_dma_sg_fallback *sgbuf)
{
size_t i, size;
if (sgbuf->pages && sgbuf->addrs) {
i = 0;
while (i < sgbuf->count) {
if (!sgbuf->pages[i] || !sgbuf->addrs[i])
break;
size = sgbuf->addrs[i] & ~PAGE_MASK;
if (WARN_ON(!size))
break;
if (sgbuf->use_dma_alloc_coherent)
dma_free_coherent(dmab->dev.dev, size << PAGE_SHIFT,
page_address(sgbuf->pages[i]),
sgbuf->addrs[i] & PAGE_MASK);
else
do_free_pages(page_address(sgbuf->pages[i]),
size << PAGE_SHIFT, false);
i += size;
}
}
kvfree(sgbuf->pages);
kvfree(sgbuf->addrs);
kfree(sgbuf);
}
static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size)
{
struct snd_dma_sg_fallback *sgbuf;
struct page **pagep, *curp;
size_t chunk, npages;
dma_addr_t *addrp;
dma_addr_t addr;
void *p;
/* correct the type */
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_SG)
dmab->dev.type = SNDRV_DMA_TYPE_DEV_SG_FALLBACK;
else if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG)
dmab->dev.type = SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK;
sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
if (!sgbuf)
return NULL;
sgbuf->use_dma_alloc_coherent = cpu_feature_enabled(X86_FEATURE_XENPV);
size = PAGE_ALIGN(size);
sgbuf->count = size >> PAGE_SHIFT;
sgbuf->pages = kvcalloc(sgbuf->count, sizeof(*sgbuf->pages), GFP_KERNEL);
sgbuf->addrs = kvcalloc(sgbuf->count, sizeof(*sgbuf->addrs), GFP_KERNEL);
if (!sgbuf->pages || !sgbuf->addrs)
goto error;
pagep = sgbuf->pages;
addrp = sgbuf->addrs;
chunk = (PAGE_SIZE - 1) << PAGE_SHIFT; /* to fit in low bits in addrs */
while (size > 0) {
chunk = min(size, chunk);
if (sgbuf->use_dma_alloc_coherent)
p = dma_alloc_coherent(dmab->dev.dev, chunk, &addr, DEFAULT_GFP);
else
p = do_alloc_pages(dmab->dev.dev, chunk, &addr, false);
if (!p) {
if (chunk <= PAGE_SIZE)
goto error;
chunk >>= 1;
chunk = PAGE_SIZE << get_order(chunk);
continue;
}
size -= chunk;
/* fill pages */
npages = chunk >> PAGE_SHIFT;
*addrp = npages; /* store in lower bits */
curp = virt_to_page(p);
while (npages--) {
*pagep++ = curp++;
*addrp++ |= addr;
addr += PAGE_SIZE;
}
}
p = vmap(sgbuf->pages, sgbuf->count, VM_MAP, PAGE_KERNEL);
if (!p)
goto error;
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK)
set_pages_array_wc(sgbuf->pages, sgbuf->count);
dmab->private_data = sgbuf;
/* store the first page address for convenience */
dmab->addr = sgbuf->addrs[0] & PAGE_MASK;
return p;
error:
__snd_dma_sg_fallback_free(dmab, sgbuf);
return NULL;
}
static void snd_dma_sg_fallback_free(struct snd_dma_buffer *dmab)
{
struct snd_dma_sg_fallback *sgbuf = dmab->private_data;
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK)
set_pages_array_wb(sgbuf->pages, sgbuf->count);
vunmap(dmab->area);
__snd_dma_sg_fallback_free(dmab, dmab->private_data);
}
static dma_addr_t snd_dma_sg_fallback_get_addr(struct snd_dma_buffer *dmab,
size_t offset)
{
struct snd_dma_sg_fallback *sgbuf = dmab->private_data;
size_t index = offset >> PAGE_SHIFT;
return (sgbuf->addrs[index] & PAGE_MASK) | (offset & ~PAGE_MASK);
}
static int snd_dma_sg_fallback_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
struct snd_dma_sg_fallback *sgbuf = dmab->private_data;
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK)
area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
return vm_map_pages(area, sgbuf->pages, sgbuf->count);
}
static const struct snd_malloc_ops snd_dma_sg_fallback_ops = {
.alloc = snd_dma_sg_fallback_alloc,
.free = snd_dma_sg_fallback_free,
.mmap = snd_dma_sg_fallback_mmap,
.get_addr = snd_dma_sg_fallback_get_addr,
/* reuse vmalloc helpers */
.get_page = snd_dma_vmalloc_get_page,
.get_chunk_size = snd_dma_vmalloc_get_chunk_size,
};
#endif /* CONFIG_SND_DMA_SGBUF */
/*
* Non-coherent pages allocator
*/
static void *snd_dma_noncoherent_alloc(struct snd_dma_buffer *dmab, size_t size)
{
void *p;
p = dma_alloc_noncoherent(dmab->dev.dev, size, &dmab->addr,
dmab->dev.dir, DEFAULT_GFP);
if (p)
dmab->dev.need_sync = dma_need_sync(dmab->dev.dev, dmab->addr);
return p;
}
static void snd_dma_noncoherent_free(struct snd_dma_buffer *dmab)
{
dma_free_noncoherent(dmab->dev.dev, dmab->bytes, dmab->area,
dmab->addr, dmab->dev.dir);
}
static int snd_dma_noncoherent_mmap(struct snd_dma_buffer *dmab,
struct vm_area_struct *area)
{
area->vm_page_prot = vm_get_page_prot(area->vm_flags);
return dma_mmap_pages(dmab->dev.dev, area,
area->vm_end - area->vm_start,
virt_to_page(dmab->area));
}
static void snd_dma_noncoherent_sync(struct snd_dma_buffer *dmab,
enum snd_dma_sync_mode mode)
{
if (mode == SNDRV_DMA_SYNC_CPU) {
if (dmab->dev.dir != DMA_TO_DEVICE)
dma_sync_single_for_cpu(dmab->dev.dev, dmab->addr,
dmab->bytes, dmab->dev.dir);
} else {
if (dmab->dev.dir != DMA_FROM_DEVICE)
dma_sync_single_for_device(dmab->dev.dev, dmab->addr,
dmab->bytes, dmab->dev.dir);
}
}
static const struct snd_malloc_ops snd_dma_noncoherent_ops = {
.alloc = snd_dma_noncoherent_alloc,
.free = snd_dma_noncoherent_free,
.mmap = snd_dma_noncoherent_mmap,
.sync = snd_dma_noncoherent_sync,
};
#endif /* CONFIG_HAS_DMA */
/*
* Entry points
*/
static const struct snd_malloc_ops *snd_dma_ops[] = {
[SNDRV_DMA_TYPE_CONTINUOUS] = &snd_dma_continuous_ops,
[SNDRV_DMA_TYPE_VMALLOC] = &snd_dma_vmalloc_ops,
#ifdef CONFIG_HAS_DMA
[SNDRV_DMA_TYPE_DEV] = &snd_dma_dev_ops,
[SNDRV_DMA_TYPE_DEV_WC] = &snd_dma_wc_ops,
[SNDRV_DMA_TYPE_NONCONTIG] = &snd_dma_noncontig_ops,
[SNDRV_DMA_TYPE_NONCOHERENT] = &snd_dma_noncoherent_ops,
#ifdef CONFIG_SND_DMA_SGBUF
[SNDRV_DMA_TYPE_DEV_WC_SG] = &snd_dma_sg_wc_ops,
#endif
#ifdef CONFIG_GENERIC_ALLOCATOR
[SNDRV_DMA_TYPE_DEV_IRAM] = &snd_dma_iram_ops,
#endif /* CONFIG_GENERIC_ALLOCATOR */
#ifdef CONFIG_SND_DMA_SGBUF
[SNDRV_DMA_TYPE_DEV_SG_FALLBACK] = &snd_dma_sg_fallback_ops,
[SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK] = &snd_dma_sg_fallback_ops,
#endif
#endif /* CONFIG_HAS_DMA */
};
static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab)
{
if (WARN_ON_ONCE(!dmab))
return NULL;
if (WARN_ON_ONCE(dmab->dev.type <= SNDRV_DMA_TYPE_UNKNOWN ||
dmab->dev.type >= ARRAY_SIZE(snd_dma_ops)))
return NULL;
return snd_dma_ops[dmab->dev.type];
}