ALSA: pcm: Use dma_bytes as size parameter in dma_mmap_coherent()

BugLink: http://bugs.launchpad.net/bugs/1762370
commit 9066ae7ff5d89c0b5daa271e2d573540097a94fa upstream.

When trying to use the driver (e.g. aplay *.wav), the 4MiB DMA buffer
will get mmapp'ed in 16KiB chunks. But this fails with the 2nd 16KiB
area, as the page offset is outside of the VMA range (size), which is
currently used as size parameter in snd_pcm_lib_default_mmap(). By
using the DMA buffer size (dma_bytes) instead, the complete DMA buffer
can be mmapp'ed and the issue is fixed.

This issue was detected on an ARM platform (TI AM57xx) using the RME
HDSP MADI PCIe soundcard.

Fixes: 657b1989dacf ("ALSA: pcm - Use dma_mmap_coherent() if available")
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index f08772568c1709ab560d7ed6db1bf418b08c984c..b01cc015a93c1e592145e483503972eebb8013b2 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -3422,7 +3422,7 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
                                         area,
                                         substream->runtime->dma_area,
                                         substream->runtime->dma_addr,
-                                        area->vm_end - area->vm_start);
+                                        substream->runtime->dma_bytes);
 #endif /* CONFIG_X86 */
        /* mmap with fault handler */
        area->vm_ops = &snd_pcm_vm_ops_data_fault;