[PATCH] ALSA: memalloc: Unify x86 SG-buffer handling (take#2)
Takashi Iwai
tiwai at suse.de
Tue Nov 9 07:22:35 CET 2021
This is a second attempt to unify the x86-specific SG-buffer handling
code with the new standard non-contiguous page handler.
The first try (in commit 2d9ea39917a4) failed due to the wrong page
and address calculations, hence reverted. Now it's corrected with the
previous fix for noncontig pages, and the proper sg page iteration by
this patch.
After the migration, SNDRV_DMA_TYPE_DMA_SG becomes identical with
SNDRV_DMA_TYPE_NONCONTIG on x86, while others still fall back to
SNDRV_DMA_TYPE_DEV.
Tested-by: Alex Xu (Hello71) <alex_y_xu at yahoo.ca>
Link: https://lore.kernel.org/r/20211017074859.24112-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
include/sound/memalloc.h | 14 +--
sound/core/Makefile | 1 -
sound/core/memalloc.c | 43 ++++++++-
sound/core/sgbuf.c | 201 ---------------------------------------
4 files changed, 46 insertions(+), 213 deletions(-)
delete mode 100644 sound/core/sgbuf.c
diff --git a/include/sound/memalloc.h b/include/sound/memalloc.h
index 1051b84e8579..653dfffb3ac8 100644
--- a/include/sound/memalloc.h
+++ b/include/sound/memalloc.h
@@ -36,13 +36,6 @@ struct snd_dma_device {
#define SNDRV_DMA_TYPE_CONTINUOUS 1 /* continuous no-DMA memory */
#define SNDRV_DMA_TYPE_DEV 2 /* generic device continuous */
#define SNDRV_DMA_TYPE_DEV_WC 5 /* continuous write-combined */
-#ifdef CONFIG_SND_DMA_SGBUF
-#define SNDRV_DMA_TYPE_DEV_SG 3 /* generic device SG-buffer */
-#define SNDRV_DMA_TYPE_DEV_WC_SG 6 /* SG write-combined */
-#else
-#define SNDRV_DMA_TYPE_DEV_SG SNDRV_DMA_TYPE_DEV /* no SG-buf support */
-#define SNDRV_DMA_TYPE_DEV_WC_SG SNDRV_DMA_TYPE_DEV_WC
-#endif
#ifdef CONFIG_GENERIC_ALLOCATOR
#define SNDRV_DMA_TYPE_DEV_IRAM 4 /* generic device iram-buffer */
#else
@@ -51,6 +44,13 @@ struct snd_dma_device {
#define SNDRV_DMA_TYPE_VMALLOC 7 /* vmalloc'ed buffer */
#define SNDRV_DMA_TYPE_NONCONTIG 8 /* non-coherent SG buffer */
#define SNDRV_DMA_TYPE_NONCOHERENT 9 /* non-coherent buffer */
+#ifdef CONFIG_SND_DMA_SGBUF
+#define SNDRV_DMA_TYPE_DEV_SG SNDRV_DMA_TYPE_NONCONTIG
+#define SNDRV_DMA_TYPE_DEV_WC_SG 6 /* SG write-combined */
+#else
+#define SNDRV_DMA_TYPE_DEV_SG SNDRV_DMA_TYPE_DEV /* no SG-buf support */
+#define SNDRV_DMA_TYPE_DEV_WC_SG SNDRV_DMA_TYPE_DEV_WC
+#endif
/*
* info for buffer allocation
diff --git a/sound/core/Makefile b/sound/core/Makefile
index 79e1407cd0de..350d704ced98 100644
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -19,7 +19,6 @@ snd-$(CONFIG_SND_JACK) += ctljack.o jack.o
snd-pcm-y := pcm.o pcm_native.o pcm_lib.o pcm_misc.o \
pcm_memory.o memalloc.o
snd-pcm-$(CONFIG_SND_PCM_TIMER) += pcm_timer.o
-snd-pcm-$(CONFIG_SND_DMA_SGBUF) += sgbuf.o
snd-pcm-$(CONFIG_SND_PCM_ELD) += pcm_drm_eld.o
snd-pcm-$(CONFIG_SND_PCM_IEC958) += pcm_iec958.o
diff --git a/sound/core/memalloc.c b/sound/core/memalloc.c
index 8c362bb5b81a..29b5c613ca23 100644
--- a/sound/core/memalloc.c
+++ b/sound/core/memalloc.c
@@ -621,6 +621,42 @@ static const struct snd_malloc_ops snd_dma_noncontig_ops = {
.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;
+ 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);
+}
+#endif /* CONFIG_SND_DMA_SGBUF */
+
/*
* Non-coherent pages allocator
*/
@@ -680,14 +716,13 @@ static const struct snd_malloc_ops *dma_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 */
#endif /* CONFIG_HAS_DMA */
-#ifdef CONFIG_SND_DMA_SGBUF
- [SNDRV_DMA_TYPE_DEV_SG] = &snd_dma_sg_ops,
- [SNDRV_DMA_TYPE_DEV_WC_SG] = &snd_dma_sg_ops,
-#endif
};
static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab)
diff --git a/sound/core/sgbuf.c b/sound/core/sgbuf.c
deleted file mode 100644
index 8352a5cdb19f..000000000000
--- a/sound/core/sgbuf.c
+++ /dev/null
@@ -1,201 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Scatter-Gather buffer
- *
- * Copyright (c) by Takashi Iwai <tiwai at suse.de>
- */
-
-#include <linux/slab.h>
-#include <linux/mm.h>
-#include <linux/vmalloc.h>
-#include <linux/export.h>
-#include <sound/memalloc.h>
-#include "memalloc_local.h"
-
-struct snd_sg_page {
- void *buf;
- dma_addr_t addr;
-};
-
-struct snd_sg_buf {
- int size; /* allocated byte size */
- int pages; /* allocated pages */
- int tblsize; /* allocated table size */
- struct snd_sg_page *table; /* address table */
- struct page **page_table; /* page table (for vmap/vunmap) */
- struct device *dev;
-};
-
-/* table entries are align to 32 */
-#define SGBUF_TBL_ALIGN 32
-#define sgbuf_align_table(tbl) ALIGN((tbl), SGBUF_TBL_ALIGN)
-
-static void snd_dma_sg_free(struct snd_dma_buffer *dmab)
-{
- struct snd_sg_buf *sgbuf = dmab->private_data;
- struct snd_dma_buffer tmpb;
- int i;
-
- if (!sgbuf)
- return;
-
- vunmap(dmab->area);
- dmab->area = NULL;
-
- tmpb.dev.type = SNDRV_DMA_TYPE_DEV;
- if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG)
- tmpb.dev.type = SNDRV_DMA_TYPE_DEV_WC;
- 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;
-}
-
-#define MAX_ALLOC_PAGES 32
-
-static void *snd_dma_sg_alloc(struct snd_dma_buffer *dmab, size_t 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;
- void *area;
-
- dmab->private_data = sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
- if (!sgbuf)
- return NULL;
- if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG) {
- type = SNDRV_DMA_TYPE_DEV_WC;
-#ifdef pgprot_noncached
- prot = pgprot_noncached(PAGE_KERNEL);
-#endif
- }
- sgbuf->dev = dmab->dev.dev;
- 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, dmab->dev.dev,
- chunk, &tmpb) < 0) {
- if (!sgbuf->pages)
- 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;
- area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, prot);
- if (!area)
- goto _failed;
- return area;
-
- _failed:
- snd_dma_sg_free(dmab); /* free the table */
- return NULL;
-}
-
-static dma_addr_t snd_dma_sg_get_addr(struct snd_dma_buffer *dmab,
- size_t offset)
-{
- struct snd_sg_buf *sgbuf = dmab->private_data;
- dma_addr_t addr;
-
- addr = sgbuf->table[offset >> PAGE_SHIFT].addr;
- addr &= ~((dma_addr_t)PAGE_SIZE - 1);
- return addr + offset % PAGE_SIZE;
-}
-
-static struct page *snd_dma_sg_get_page(struct snd_dma_buffer *dmab,
- size_t offset)
-{
- struct snd_sg_buf *sgbuf = dmab->private_data;
- unsigned int idx = offset >> PAGE_SHIFT;
-
- if (idx >= (unsigned int)sgbuf->pages)
- return NULL;
- return sgbuf->page_table[idx];
-}
-
-static unsigned int snd_dma_sg_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;
-}
-
-static int snd_dma_sg_mmap(struct snd_dma_buffer *dmab,
- struct vm_area_struct *area)
-{
- if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG)
- area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
- return -ENOENT; /* continue with the default mmap handler */
-}
-
-const struct snd_malloc_ops snd_dma_sg_ops = {
- .alloc = snd_dma_sg_alloc,
- .free = snd_dma_sg_free,
- .get_addr = snd_dma_sg_get_addr,
- .get_page = snd_dma_sg_get_page,
- .get_chunk_size = snd_dma_sg_get_chunk_size,
- .mmap = snd_dma_sg_mmap,
-};
--
2.26.2
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