mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 11:19:37 +00:00
![Thomas Gleixner](/assets/img/avatar_default.png)
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
161 lines
3.8 KiB
C
161 lines
3.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Scatter-Gather buffer
|
|
*
|
|
* Copyright (c) by Takashi Iwai <tiwai@suse.de>
|
|
*/
|
|
|
|
#include <linux/slab.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/export.h>
|
|
#include <asm/pgtable.h>
|
|
#include <sound/memalloc.h>
|
|
|
|
|
|
/* table entries are align to 32 */
|
|
#define SGBUF_TBL_ALIGN 32
|
|
#define sgbuf_align_table(tbl) ALIGN((tbl), SGBUF_TBL_ALIGN)
|
|
|
|
int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab)
|
|
{
|
|
struct snd_sg_buf *sgbuf = dmab->private_data;
|
|
struct snd_dma_buffer tmpb;
|
|
int i;
|
|
|
|
if (! sgbuf)
|
|
return -EINVAL;
|
|
|
|
vunmap(dmab->area);
|
|
dmab->area = NULL;
|
|
|
|
tmpb.dev.type = SNDRV_DMA_TYPE_DEV;
|
|
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC_SG)
|
|
tmpb.dev.type = SNDRV_DMA_TYPE_DEV_UC;
|
|
tmpb.dev.dev = sgbuf->dev;
|
|
for (i = 0; i < sgbuf->pages; i++) {
|
|
if (!(sgbuf->table[i].addr & ~PAGE_MASK))
|
|
continue; /* continuous pages */
|
|
tmpb.area = sgbuf->table[i].buf;
|
|
tmpb.addr = sgbuf->table[i].addr & PAGE_MASK;
|
|
tmpb.bytes = (sgbuf->table[i].addr & ~PAGE_MASK) << PAGE_SHIFT;
|
|
snd_dma_free_pages(&tmpb);
|
|
}
|
|
|
|
kfree(sgbuf->table);
|
|
kfree(sgbuf->page_table);
|
|
kfree(sgbuf);
|
|
dmab->private_data = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define MAX_ALLOC_PAGES 32
|
|
|
|
void *snd_malloc_sgbuf_pages(struct device *device,
|
|
size_t size, struct snd_dma_buffer *dmab,
|
|
size_t *res_size)
|
|
{
|
|
struct snd_sg_buf *sgbuf;
|
|
unsigned int i, pages, chunk, maxpages;
|
|
struct snd_dma_buffer tmpb;
|
|
struct snd_sg_page *table;
|
|
struct page **pgtable;
|
|
int type = SNDRV_DMA_TYPE_DEV;
|
|
pgprot_t prot = PAGE_KERNEL;
|
|
|
|
dmab->area = NULL;
|
|
dmab->addr = 0;
|
|
dmab->private_data = sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
|
|
if (! sgbuf)
|
|
return NULL;
|
|
if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC_SG) {
|
|
type = SNDRV_DMA_TYPE_DEV_UC;
|
|
#ifdef pgprot_noncached
|
|
prot = pgprot_noncached(PAGE_KERNEL);
|
|
#endif
|
|
}
|
|
sgbuf->dev = device;
|
|
pages = snd_sgbuf_aligned_pages(size);
|
|
sgbuf->tblsize = sgbuf_align_table(pages);
|
|
table = kcalloc(sgbuf->tblsize, sizeof(*table), GFP_KERNEL);
|
|
if (!table)
|
|
goto _failed;
|
|
sgbuf->table = table;
|
|
pgtable = kcalloc(sgbuf->tblsize, sizeof(*pgtable), GFP_KERNEL);
|
|
if (!pgtable)
|
|
goto _failed;
|
|
sgbuf->page_table = pgtable;
|
|
|
|
/* allocate pages */
|
|
maxpages = MAX_ALLOC_PAGES;
|
|
while (pages > 0) {
|
|
chunk = pages;
|
|
/* don't be too eager to take a huge chunk */
|
|
if (chunk > maxpages)
|
|
chunk = maxpages;
|
|
chunk <<= PAGE_SHIFT;
|
|
if (snd_dma_alloc_pages_fallback(type, device,
|
|
chunk, &tmpb) < 0) {
|
|
if (!sgbuf->pages)
|
|
goto _failed;
|
|
if (!res_size)
|
|
goto _failed;
|
|
size = sgbuf->pages * PAGE_SIZE;
|
|
break;
|
|
}
|
|
chunk = tmpb.bytes >> PAGE_SHIFT;
|
|
for (i = 0; i < chunk; i++) {
|
|
table->buf = tmpb.area;
|
|
table->addr = tmpb.addr;
|
|
if (!i)
|
|
table->addr |= chunk; /* mark head */
|
|
table++;
|
|
*pgtable++ = virt_to_page(tmpb.area);
|
|
tmpb.area += PAGE_SIZE;
|
|
tmpb.addr += PAGE_SIZE;
|
|
}
|
|
sgbuf->pages += chunk;
|
|
pages -= chunk;
|
|
if (chunk < maxpages)
|
|
maxpages = chunk;
|
|
}
|
|
|
|
sgbuf->size = size;
|
|
dmab->area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, prot);
|
|
if (! dmab->area)
|
|
goto _failed;
|
|
if (res_size)
|
|
*res_size = sgbuf->size;
|
|
return dmab->area;
|
|
|
|
_failed:
|
|
snd_free_sgbuf_pages(dmab); /* free the table */
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* compute the max chunk size with continuous pages on sg-buffer
|
|
*/
|
|
unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
|
|
unsigned int ofs, unsigned int size)
|
|
{
|
|
struct snd_sg_buf *sg = dmab->private_data;
|
|
unsigned int start, end, pg;
|
|
|
|
start = ofs >> PAGE_SHIFT;
|
|
end = (ofs + size - 1) >> PAGE_SHIFT;
|
|
/* check page continuity */
|
|
pg = sg->table[start].addr >> PAGE_SHIFT;
|
|
for (;;) {
|
|
start++;
|
|
if (start > end)
|
|
break;
|
|
pg++;
|
|
if ((sg->table[start].addr >> PAGE_SHIFT) != pg)
|
|
return (start << PAGE_SHIFT) - ofs;
|
|
}
|
|
/* ok, all on continuous pages */
|
|
return size;
|
|
}
|
|
EXPORT_SYMBOL(snd_sgbuf_get_chunk_size);
|