We've had an x86-specific SG-buffer handling code, but now it can be
merged gracefully with the standard non-contiguous DMA pages.
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.
The remaining problem is about the SG-buffer with WC pages: the DMA
core stuff on x86 doesn't treat it well, so we still need some special
handling to manipulate the page attribute manually. The mmap handler
for SNDRV_DMA_TYPE_DEV_SG_WC still returns -ENOENT intentionally for
the fallback to the default handler.
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
include/sound/memalloc.h | 14 +--
sound/core/Makefile | 1 -
sound/core/memalloc.c | 51 +++++++++-
sound/core/sgbuf.c | 201 ---------------------------------------
4 files changed, 54 insertions(+), 213 deletions(-)
delete mode 100644 sound/core/sgbuf.c
diff --git a/include/sound/memalloc.h b/include/sound/memalloc.h
index 0bdaa6753282..df615052dad4 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 d774792850f3..2762f03d9b7b 100644
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -17,7 +17,6 @@ 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 99681e651223..acdebecf1a2e 100644
--- a/sound/core/memalloc.c
+++ b/sound/core/memalloc.c
@@ -560,6 +560,50 @@ static const struct snd_malloc_ops snd_dma_noncontig_ops = {
.get_chunk_size = snd_dma_vmalloc_get_chunk_size,
};
+/* x86-specific SG-buffer with WC pages */
+#ifdef CONFIG_SND_DMA_SGBUF
+#define vmalloc_to_virt(v) (unsigned long)page_to_virt(vmalloc_to_page(v))
+
+static void *snd_dma_sg_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
+{
+ void *p = snd_dma_noncontig_alloc(dmab, size);
+ size_t ofs;
+
+ if (!p)
+ return NULL;
+ for (ofs = 0; ofs < size; ofs += PAGE_SIZE)
+ set_memory_uc(vmalloc_to_virt(p + ofs), 1);
+ return p;
+}
+
+static void snd_dma_sg_wc_free(struct snd_dma_buffer *dmab)
+{
+ size_t ofs;
+
+ for (ofs = 0; ofs < dmab->bytes; ofs += PAGE_SIZE)
+ set_memory_wb(vmalloc_to_virt(dmab->area + ofs), 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);
+ /* FIXME: dma_mmap_noncontiguous() works? */
+ return -ENOENT; /* continue with the default mmap handler */
+}
+
+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_vmalloc_get_addr,
+ .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
*/
@@ -619,14 +663,13 @@ 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@xxxxxxx>
- */
-
-#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
