Merge branch 'topic/dma-fix2' into for-next

Pull the fix for potential PCM SG-buffer problems.

Link: https://lore.kernel.org/r/20200615160045.2703-1-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/memalloc.h

@@ -94,7 +94,11 @@ static inline dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab,
 					   size_t offset)
 {
 	struct snd_sg_buf *sgbuf = dmab->private_data;
-	dma_addr_t addr = sgbuf->table[offset >> PAGE_SHIFT].addr;
+	dma_addr_t addr;
+
+	if (!sgbuf)
+		return dmab->addr + offset;
+	addr = sgbuf->table[offset >> PAGE_SHIFT].addr;
 	addr &= ~((dma_addr_t)PAGE_SIZE - 1);
 	return addr + offset % PAGE_SIZE;
 }
@@ -106,6 +110,9 @@ static inline void *snd_sgbuf_get_ptr(struct snd_dma_buffer *dmab,
 				     size_t offset)
 {
 	struct snd_sg_buf *sgbuf = dmab->private_data;
+
+	if (!sgbuf)
+		return dmab->area + offset;
 	return sgbuf->table[offset >> PAGE_SHIFT].buf + offset % PAGE_SIZE;
 }
 

sound/core/memalloc.c

@@ -135,16 +135,17 @@ int snd_dma_alloc_pages(int type, struct device *device, size_t size,
 	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);
-		dmab->addr = 0;
 		break;
 	case SNDRV_DMA_TYPE_VMALLOC:
 		gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL | __GFP_HIGHMEM);
 		dmab->area = __vmalloc(size, gfp);
-		dmab->addr = 0;
 		break;
 #ifdef CONFIG_HAS_DMA
 #ifdef CONFIG_GENERIC_ALLOCATOR
@@ -171,8 +172,6 @@ int snd_dma_alloc_pages(int type, struct device *device, size_t size,
 #endif
 	default:
 		pr_err("snd-malloc: invalid device type %d\n", type);
-		dmab->area = NULL;
-		dmab->addr = 0;
 		return -ENXIO;
 	}
 	if (! dmab->area)

sound/core/pcm_memory.c

@@ -11,6 +11,7 @@
 #include <linux/moduleparam.h>
 #include <linux/vmalloc.h>
 #include <linux/export.h>
+#include <linux/dma-mapping.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/info.h>
@@ -39,6 +40,18 @@ static int do_alloc_pages(struct snd_card *card, int type, struct device *dev,
 	if (max_alloc_per_card &&
 	    card->total_pcm_alloc_bytes + size > max_alloc_per_card)
 		return -ENOMEM;
+
+	if (IS_ENABLED(CONFIG_SND_DMA_SGBUF) &&
+	    (type == SNDRV_DMA_TYPE_DEV_SG || type == SNDRV_DMA_TYPE_DEV_UC_SG) &&
+	    !dma_is_direct(get_dma_ops(dev))) {
+		/* mutate to continuous page allocation */
+		dev_dbg(dev, "Use continuous page allocator\n");
+		if (type == SNDRV_DMA_TYPE_DEV_SG)
+			type = SNDRV_DMA_TYPE_DEV;
+		else
+			type = SNDRV_DMA_TYPE_DEV_UC;
+	}
+
 	err = snd_dma_alloc_pages(type, dev, size, dmab);
 	if (!err) {
 		mutex_lock(&card->memory_mutex);

sound/core/pcm_native.c

@@ -3713,7 +3713,6 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
 				area->vm_end - area->vm_start, area->vm_page_prot);
 	}
 #endif /* CONFIG_GENERIC_ALLOCATOR */
-#ifndef CONFIG_X86 /* for avoiding warnings arch/x86/mm/pat.c */
 	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
 	    (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV ||
 	     substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_UC))
@@ -3722,7 +3721,6 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
 					 substream->runtime->dma_area,
 					 substream->runtime->dma_addr,
 					 substream->runtime->dma_bytes);
-#endif /* CONFIG_X86 */
 	/* mmap with fault handler */
 	area->vm_ops = &snd_pcm_vm_ops_data_fault;
 	return 0;

sound/core/sgbuf.c

@@ -142,6 +142,9 @@ unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
 	struct snd_sg_buf *sg = dmab->private_data;
 	unsigned int start, end, pg;
 
+	if (!sg)
+		return size;
+
 	start = ofs >> PAGE_SHIFT;
 	end = (ofs + size - 1) >> PAGE_SHIFT;
 	/* check page continuity */