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media: videobuf-dma-contig: use dma_mmap_coherent

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[ Upstream commit b3dc3f8e49 ]

dma_alloc_coherent does not return a physical address, but a DMA address,
which might be remapped or have an offset.  Passing the DMA address to
vm_iomap_memory is thus broken.

Use the proper dma_mmap_coherent helper instead, and stop passing
__GFP_COMP to dma_alloc_coherent, as the memory management inside the
DMA allocator is hidden from the callers and does not require it.

With this the gfp_t argument to __videobuf_dc_alloc can be removed and
hard coded to GFP_KERNEL.

Fixes: a8f3c203e1 ("[media] videobuf-dma-contig: add cache support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Christoph Hellwig 2019-12-18 11:39:07 +01:00 committed by Greg Kroah-Hartman
parent 9ca9d7fd7d
commit 61688b8819
1 changed files with 8 additions and 14 deletions
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22
drivers/media/v4l2-core/videobuf-dma-contig.c
View file

@ -36,12 +36,11 @@ struct videobuf_dma_contig_memory {
static int __videobuf_dc_alloc(struct device *dev,
struct videobuf_dma_contig_memory *mem,
unsigned long size, gfp_t flags)
unsigned long size)
{
mem->size = size;
mem->vaddr = dma_alloc_coherent(dev, mem->size,
&mem->dma_handle, flags);
mem->vaddr = dma_alloc_coherent(dev, mem->size, &mem->dma_handle,
GFP_KERNEL);
if (!mem->vaddr) {
dev_err(dev, "memory alloc size %ld failed\n", mem->size);
return -ENOMEM;
@ -258,8 +257,7 @@ static int __videobuf_iolock(struct videobuf_queue *q,
return videobuf_dma_contig_user_get(mem, vb);
/* allocate memory for the read() method */
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size),
GFP_KERNEL))
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size)))
return -ENOMEM;
break;
case V4L2_MEMORY_OVERLAY:
@ -295,22 +293,18 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize),
GFP_KERNEL | __GFP_COMP))
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize)))
goto error;
/* Try to remap memory */
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
/* the "vm_pgoff" is just used in v4l2 to find the
* corresponding buffer data structure which is allocated
* earlier and it does not mean the offset from the physical
* buffer start address as usual. So set it to 0 to pass
* the sanity check in vm_iomap_memory().
* the sanity check in dma_mmap_coherent().
*/
vma->vm_pgoff = 0;
retval = vm_iomap_memory(vma, mem->dma_handle, mem->size);
retval = dma_mmap_coherent(q->dev, vma, mem->vaddr, mem->dma_handle,
mem->size);
if (retval) {
dev_err(q->dev, "mmap: remap failed with error %d. ",
retval);