+int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size);
+int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream);
+
+int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
+ size_t size, gfp_t gfp_flags);
+int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream);
+struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
+ unsigned long offset);
+#if 0 /* for kernel-doc */
+/**
+ * snd_pcm_lib_alloc_vmalloc_buffer - allocate virtual DMA buffer
+ * @substream: the substream to allocate the buffer to
+ * @size: the requested buffer size, in bytes
+ *
+ * Allocates the PCM substream buffer using vmalloc(), i.e., the memory is
+ * contiguous in kernel virtual space, but not in physical memory. Use this
+ * if the buffer is accessed by kernel code but not by device DMA.
+ *
+ * Returns 1 if the buffer was changed, 0 if not changed, or a negative error
+ * code.
+ */
+static int snd_pcm_lib_alloc_vmalloc_buffer
+ (struct snd_pcm_substream *substream, size_t size);
+/**
+ * snd_pcm_lib_alloc_vmalloc_32_buffer - allocate 32-bit-addressable buffer
+ * @substream: the substream to allocate the buffer to
+ * @size: the requested buffer size, in bytes
+ *
+ * This function works like snd_pcm_lib_alloc_vmalloc_buffer(), but uses
+ * vmalloc_32(), i.e., the pages are allocated from 32-bit-addressable memory.
+ */
+static int snd_pcm_lib_alloc_vmalloc_32_buffer
+ (struct snd_pcm_substream *substream, size_t size);
+#endif
+#define snd_pcm_lib_alloc_vmalloc_buffer(subs, size) \
+ _snd_pcm_lib_alloc_vmalloc_buffer \
+ (subs, size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO)
+#define snd_pcm_lib_alloc_vmalloc_32_buffer(subs, size) \
+ _snd_pcm_lib_alloc_vmalloc_buffer \
+ (subs, size, GFP_KERNEL | GFP_DMA32 | __GFP_ZERO)
+
+#ifdef CONFIG_SND_DMA_SGBUF
+/*
+ * SG-buffer handling
+ */
+#define snd_pcm_substream_sgbuf(substream) \
+ ((substream)->runtime->dma_buffer_p->private_data)
+
+static inline dma_addr_t
+snd_pcm_sgbuf_get_addr(struct snd_pcm_substream *substream, unsigned int ofs)
+{
+ struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream);
+ return snd_sgbuf_get_addr(sg, ofs);
+}
+
+static inline void *
+snd_pcm_sgbuf_get_ptr(struct snd_pcm_substream *substream, unsigned int ofs)
+{
+ struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream);
+ return snd_sgbuf_get_ptr(sg, ofs);
+}