From 31bedfa5068936b15a388842be1d03cdd1bdfb07 Mon Sep 17 00:00:00 2001 From: Muralidharan Karicheri Date: Thu, 10 Dec 2009 16:47:48 -0300 Subject: [PATCH] V4L/DVB (13598): videobuf_dma_contig_user_get() for non-aligned offsets If a USERPTR address that is not aligned to page boundary is passed to the videobuf_dma_contig_user_get() function, it saves a page aligned address to the dma_handle. This is not correct. This issue is observed when using USERPTR IO machism for buffer exchange. Updates from last version:- Adding offset for size calculation as per comment from Magnus Damm. This ensures the last page is also included for checking if memory is contiguous. Signed-off-by: Muralidharan Karicheri Acked-by: Magnus Damm Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/videobuf-dma-contig.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/media/video/videobuf-dma-contig.c b/drivers/media/video/videobuf-dma-contig.c index d25f28461da1..22c01097e8a8 100644 --- a/drivers/media/video/videobuf-dma-contig.c +++ b/drivers/media/video/videobuf-dma-contig.c @@ -141,9 +141,11 @@ static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem, struct vm_area_struct *vma; unsigned long prev_pfn, this_pfn; unsigned long pages_done, user_address; + unsigned int offset; int ret; - mem->size = PAGE_ALIGN(vb->size); + offset = vb->baddr & ~PAGE_MASK; + mem->size = PAGE_ALIGN(vb->size + offset); mem->is_userptr = 0; ret = -EINVAL; @@ -166,7 +168,7 @@ static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem, break; if (pages_done == 0) - mem->dma_handle = this_pfn << PAGE_SHIFT; + mem->dma_handle = (this_pfn << PAGE_SHIFT) + offset; else if (this_pfn != (prev_pfn + 1)) ret = -EFAULT; -- 2.39.5