V4L/DVB (6058): ivtv: add support for highmem udma
When trying to DMA userspace buffers to the cx23415 you need to check
whether the page is in highmem. If this is the case, then bounce buffers
have to be used to allow DMA.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/ivtv/ivtv-yuv.c b/drivers/media/video/ivtv/ivtv-yuv.c
index fa8c76f..2ae7556 100644
--- a/drivers/media/video/ivtv/ivtv-yuv.c
+++ b/drivers/media/video/ivtv/ivtv-yuv.c
@@ -83,7 +83,14 @@
}
/* Fill & map SG List */
- ivtv_udma_fill_sg_list (dma, &uv_dma, ivtv_udma_fill_sg_list (dma, &y_dma, 0));
+ if (ivtv_udma_fill_sg_list (dma, &uv_dma, ivtv_udma_fill_sg_list (dma, &y_dma, 0))) {
+ IVTV_DEBUG_WARN("could not allocate bounce buffers for highmem userspace buffers\n");
+ for (i = 0; i < dma->page_count; i++) {
+ put_page(dma->map[i]);
+ }
+ dma->page_count = 0;
+ return -ENOMEM;
+ }
dma->SG_length = pci_map_sg(itv->dev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE);
/* Fill SG Array with new values */